Commit | Line | Data |
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60c778b2 | 1 | /* SCTP kernel implementation |
1da177e4 LT |
2 | * (C) Copyright IBM Corp. 2001, 2004 |
3 | * Copyright (c) 1999-2000 Cisco, Inc. | |
4 | * Copyright (c) 1999-2001 Motorola, Inc. | |
5 | * Copyright (c) 2001-2002 Intel Corp. | |
6 | * Copyright (c) 2002 Nokia Corp. | |
7 | * | |
60c778b2 | 8 | * This is part of the SCTP Linux Kernel Implementation. |
1da177e4 LT |
9 | * |
10 | * These are the state functions for the state machine. | |
11 | * | |
60c778b2 | 12 | * This SCTP implementation is free software; |
1da177e4 LT |
13 | * you can redistribute it and/or modify it under the terms of |
14 | * the GNU General Public License as published by | |
15 | * the Free Software Foundation; either version 2, or (at your option) | |
16 | * any later version. | |
17 | * | |
60c778b2 | 18 | * This SCTP implementation is distributed in the hope that it |
1da177e4 LT |
19 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
20 | * ************************ | |
21 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
22 | * See the GNU General Public License for more details. | |
23 | * | |
24 | * You should have received a copy of the GNU General Public License | |
4b2f13a2 JK |
25 | * along with GNU CC; see the file COPYING. If not, see |
26 | * <http://www.gnu.org/licenses/>. | |
1da177e4 LT |
27 | * |
28 | * Please send any bug reports or fixes you make to the | |
29 | * email address(es): | |
91705c61 | 30 | * lksctp developers <linux-sctp@vger.kernel.org> |
1da177e4 | 31 | * |
1da177e4 LT |
32 | * Written or modified by: |
33 | * La Monte H.P. Yarroll <piggy@acm.org> | |
34 | * Karl Knutson <karl@athena.chicago.il.us> | |
35 | * Mathew Kotowsky <kotowsky@sctp.org> | |
36 | * Sridhar Samudrala <samudrala@us.ibm.com> | |
37 | * Jon Grimm <jgrimm@us.ibm.com> | |
38 | * Hui Huang <hui.huang@nokia.com> | |
39 | * Dajiang Zhang <dajiang.zhang@nokia.com> | |
40 | * Daisy Chang <daisyc@us.ibm.com> | |
41 | * Ardelle Fan <ardelle.fan@intel.com> | |
42 | * Ryan Layer <rmlayer@us.ibm.com> | |
43 | * Kevin Gao <kevin.gao@intel.com> | |
1da177e4 LT |
44 | */ |
45 | ||
145ce502 JP |
46 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
47 | ||
1da177e4 LT |
48 | #include <linux/types.h> |
49 | #include <linux/kernel.h> | |
50 | #include <linux/ip.h> | |
51 | #include <linux/ipv6.h> | |
52 | #include <linux/net.h> | |
53 | #include <linux/inet.h> | |
5a0e3ad6 | 54 | #include <linux/slab.h> |
1da177e4 LT |
55 | #include <net/sock.h> |
56 | #include <net/inet_ecn.h> | |
57 | #include <linux/skbuff.h> | |
58 | #include <net/sctp/sctp.h> | |
59 | #include <net/sctp/sm.h> | |
60 | #include <net/sctp/structs.h> | |
61 | ||
24cb81a6 EB |
62 | static struct sctp_packet *sctp_abort_pkt_new(struct net *net, |
63 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
64 | const struct sctp_association *asoc, |
65 | struct sctp_chunk *chunk, | |
66 | const void *payload, | |
67 | size_t paylen); | |
68 | static int sctp_eat_data(const struct sctp_association *asoc, | |
69 | struct sctp_chunk *chunk, | |
70 | sctp_cmd_seq_t *commands); | |
2ce95503 EB |
71 | static struct sctp_packet *sctp_ootb_pkt_new(struct net *net, |
72 | const struct sctp_association *asoc, | |
1da177e4 | 73 | const struct sctp_chunk *chunk); |
24cb81a6 EB |
74 | static void sctp_send_stale_cookie_err(struct net *net, |
75 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
76 | const struct sctp_association *asoc, |
77 | const struct sctp_chunk *chunk, | |
78 | sctp_cmd_seq_t *commands, | |
79 | struct sctp_chunk *err_chunk); | |
24cb81a6 EB |
80 | static sctp_disposition_t sctp_sf_do_5_2_6_stale(struct net *net, |
81 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
82 | const struct sctp_association *asoc, |
83 | const sctp_subtype_t type, | |
84 | void *arg, | |
85 | sctp_cmd_seq_t *commands); | |
24cb81a6 EB |
86 | static sctp_disposition_t sctp_sf_shut_8_4_5(struct net *net, |
87 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
88 | const struct sctp_association *asoc, |
89 | const sctp_subtype_t type, | |
90 | void *arg, | |
91 | sctp_cmd_seq_t *commands); | |
24cb81a6 EB |
92 | static sctp_disposition_t sctp_sf_tabort_8_4_8(struct net *net, |
93 | const struct sctp_endpoint *ep, | |
ece25dfa VY |
94 | const struct sctp_association *asoc, |
95 | const sctp_subtype_t type, | |
96 | void *arg, | |
97 | sctp_cmd_seq_t *commands); | |
1da177e4 LT |
98 | static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk); |
99 | ||
24cb81a6 EB |
100 | static sctp_disposition_t sctp_stop_t1_and_abort(struct net *net, |
101 | sctp_cmd_seq_t *commands, | |
f94c0198 | 102 | __be16 error, int sk_err, |
52c1da39 AB |
103 | const struct sctp_association *asoc, |
104 | struct sctp_transport *transport); | |
105 | ||
aecedeab | 106 | static sctp_disposition_t sctp_sf_abort_violation( |
24cb81a6 | 107 | struct net *net, |
ece25dfa | 108 | const struct sctp_endpoint *ep, |
aecedeab WY |
109 | const struct sctp_association *asoc, |
110 | void *arg, | |
111 | sctp_cmd_seq_t *commands, | |
112 | const __u8 *payload, | |
113 | const size_t paylen); | |
114 | ||
52c1da39 | 115 | static sctp_disposition_t sctp_sf_violation_chunklen( |
24cb81a6 | 116 | struct net *net, |
52c1da39 AB |
117 | const struct sctp_endpoint *ep, |
118 | const struct sctp_association *asoc, | |
119 | const sctp_subtype_t type, | |
120 | void *arg, | |
121 | sctp_cmd_seq_t *commands); | |
1da177e4 | 122 | |
6f4c618d | 123 | static sctp_disposition_t sctp_sf_violation_paramlen( |
24cb81a6 | 124 | struct net *net, |
6f4c618d WY |
125 | const struct sctp_endpoint *ep, |
126 | const struct sctp_association *asoc, | |
127 | const sctp_subtype_t type, | |
ba016670 | 128 | void *arg, void *ext, |
6f4c618d WY |
129 | sctp_cmd_seq_t *commands); |
130 | ||
aecedeab | 131 | static sctp_disposition_t sctp_sf_violation_ctsn( |
24cb81a6 | 132 | struct net *net, |
aecedeab WY |
133 | const struct sctp_endpoint *ep, |
134 | const struct sctp_association *asoc, | |
135 | const sctp_subtype_t type, | |
136 | void *arg, | |
137 | sctp_cmd_seq_t *commands); | |
138 | ||
ece25dfa | 139 | static sctp_disposition_t sctp_sf_violation_chunk( |
24cb81a6 | 140 | struct net *net, |
ece25dfa VY |
141 | const struct sctp_endpoint *ep, |
142 | const struct sctp_association *asoc, | |
143 | const sctp_subtype_t type, | |
144 | void *arg, | |
145 | sctp_cmd_seq_t *commands); | |
146 | ||
24cb81a6 EB |
147 | static sctp_ierror_t sctp_sf_authenticate(struct net *net, |
148 | const struct sctp_endpoint *ep, | |
bbd0d598 VY |
149 | const struct sctp_association *asoc, |
150 | const sctp_subtype_t type, | |
151 | struct sctp_chunk *chunk); | |
152 | ||
24cb81a6 EB |
153 | static sctp_disposition_t __sctp_sf_do_9_1_abort(struct net *net, |
154 | const struct sctp_endpoint *ep, | |
75205f47 VY |
155 | const struct sctp_association *asoc, |
156 | const sctp_subtype_t type, | |
157 | void *arg, | |
158 | sctp_cmd_seq_t *commands); | |
159 | ||
1da177e4 LT |
160 | /* Small helper function that checks if the chunk length |
161 | * is of the appropriate length. The 'required_length' argument | |
162 | * is set to be the size of a specific chunk we are testing. | |
163 | * Return Values: 1 = Valid length | |
164 | * 0 = Invalid length | |
165 | * | |
166 | */ | |
167 | static inline int | |
168 | sctp_chunk_length_valid(struct sctp_chunk *chunk, | |
169 | __u16 required_length) | |
170 | { | |
171 | __u16 chunk_length = ntohs(chunk->chunk_hdr->length); | |
172 | ||
173 | if (unlikely(chunk_length < required_length)) | |
174 | return 0; | |
175 | ||
176 | return 1; | |
177 | } | |
178 | ||
179 | /********************************************************** | |
180 | * These are the state functions for handling chunk events. | |
181 | **********************************************************/ | |
182 | ||
183 | /* | |
184 | * Process the final SHUTDOWN COMPLETE. | |
185 | * | |
186 | * Section: 4 (C) (diagram), 9.2 | |
187 | * Upon reception of the SHUTDOWN COMPLETE chunk the endpoint will verify | |
188 | * that it is in SHUTDOWN-ACK-SENT state, if it is not the chunk should be | |
189 | * discarded. If the endpoint is in the SHUTDOWN-ACK-SENT state the endpoint | |
190 | * should stop the T2-shutdown timer and remove all knowledge of the | |
191 | * association (and thus the association enters the CLOSED state). | |
192 | * | |
047a2428 | 193 | * Verification Tag: 8.5.1(C), sctpimpguide 2.41. |
1da177e4 LT |
194 | * C) Rules for packet carrying SHUTDOWN COMPLETE: |
195 | * ... | |
047a2428 JF |
196 | * - The receiver of a SHUTDOWN COMPLETE shall accept the packet |
197 | * if the Verification Tag field of the packet matches its own tag and | |
198 | * the T bit is not set | |
199 | * OR | |
200 | * it is set to its peer's tag and the T bit is set in the Chunk | |
201 | * Flags. | |
202 | * Otherwise, the receiver MUST silently discard the packet | |
203 | * and take no further action. An endpoint MUST ignore the | |
204 | * SHUTDOWN COMPLETE if it is not in the SHUTDOWN-ACK-SENT state. | |
1da177e4 LT |
205 | * |
206 | * Inputs | |
207 | * (endpoint, asoc, chunk) | |
208 | * | |
209 | * Outputs | |
210 | * (asoc, reply_msg, msg_up, timers, counters) | |
211 | * | |
212 | * The return value is the disposition of the chunk. | |
213 | */ | |
24cb81a6 EB |
214 | sctp_disposition_t sctp_sf_do_4_C(struct net *net, |
215 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
216 | const struct sctp_association *asoc, |
217 | const sctp_subtype_t type, | |
218 | void *arg, | |
219 | sctp_cmd_seq_t *commands) | |
220 | { | |
221 | struct sctp_chunk *chunk = arg; | |
222 | struct sctp_ulpevent *ev; | |
223 | ||
ece25dfa | 224 | if (!sctp_vtag_verify_either(chunk, asoc)) |
24cb81a6 | 225 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
ece25dfa | 226 | |
1da177e4 LT |
227 | /* RFC 2960 6.10 Bundling |
228 | * | |
229 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
230 | * SHUTDOWN COMPLETE with any other chunks. | |
231 | */ | |
232 | if (!chunk->singleton) | |
24cb81a6 | 233 | return sctp_sf_violation_chunk(net, ep, asoc, type, arg, commands); |
1da177e4 | 234 | |
ece25dfa VY |
235 | /* Make sure that the SHUTDOWN_COMPLETE chunk has a valid length. */ |
236 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 237 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa | 238 | commands); |
1da177e4 LT |
239 | |
240 | /* RFC 2960 10.2 SCTP-to-ULP | |
241 | * | |
242 | * H) SHUTDOWN COMPLETE notification | |
243 | * | |
244 | * When SCTP completes the shutdown procedures (section 9.2) this | |
245 | * notification is passed to the upper layer. | |
246 | */ | |
247 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP, | |
a5a35e76 | 248 | 0, 0, 0, NULL, GFP_ATOMIC); |
df7deeb5 VY |
249 | if (ev) |
250 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
d808ad9a | 251 | SCTP_ULPEVENT(ev)); |
1da177e4 LT |
252 | |
253 | /* Upon reception of the SHUTDOWN COMPLETE chunk the endpoint | |
254 | * will verify that it is in SHUTDOWN-ACK-SENT state, if it is | |
255 | * not the chunk should be discarded. If the endpoint is in | |
256 | * the SHUTDOWN-ACK-SENT state the endpoint should stop the | |
257 | * T2-shutdown timer and remove all knowledge of the | |
258 | * association (and thus the association enters the CLOSED | |
259 | * state). | |
260 | */ | |
261 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
262 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
263 | ||
264 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
265 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
266 | ||
267 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
268 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
269 | ||
b01a2407 EB |
270 | SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS); |
271 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
272 | |
273 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
274 | ||
275 | return SCTP_DISPOSITION_DELETE_TCB; | |
1da177e4 LT |
276 | } |
277 | ||
278 | /* | |
279 | * Respond to a normal INIT chunk. | |
280 | * We are the side that is being asked for an association. | |
281 | * | |
282 | * Section: 5.1 Normal Establishment of an Association, B | |
283 | * B) "Z" shall respond immediately with an INIT ACK chunk. The | |
284 | * destination IP address of the INIT ACK MUST be set to the source | |
285 | * IP address of the INIT to which this INIT ACK is responding. In | |
286 | * the response, besides filling in other parameters, "Z" must set the | |
287 | * Verification Tag field to Tag_A, and also provide its own | |
288 | * Verification Tag (Tag_Z) in the Initiate Tag field. | |
289 | * | |
d808ad9a | 290 | * Verification Tag: Must be 0. |
1da177e4 LT |
291 | * |
292 | * Inputs | |
293 | * (endpoint, asoc, chunk) | |
294 | * | |
295 | * Outputs | |
296 | * (asoc, reply_msg, msg_up, timers, counters) | |
297 | * | |
298 | * The return value is the disposition of the chunk. | |
299 | */ | |
24cb81a6 EB |
300 | sctp_disposition_t sctp_sf_do_5_1B_init(struct net *net, |
301 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
302 | const struct sctp_association *asoc, |
303 | const sctp_subtype_t type, | |
304 | void *arg, | |
305 | sctp_cmd_seq_t *commands) | |
306 | { | |
307 | struct sctp_chunk *chunk = arg; | |
308 | struct sctp_chunk *repl; | |
309 | struct sctp_association *new_asoc; | |
310 | struct sctp_chunk *err_chunk; | |
311 | struct sctp_packet *packet; | |
312 | sctp_unrecognized_param_t *unk_param; | |
1da177e4 LT |
313 | int len; |
314 | ||
315 | /* 6.10 Bundling | |
316 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
317 | * SHUTDOWN COMPLETE with any other chunks. | |
d808ad9a | 318 | * |
1da177e4 LT |
319 | * IG Section 2.11.2 |
320 | * Furthermore, we require that the receiver of an INIT chunk MUST | |
321 | * enforce these rules by silently discarding an arriving packet | |
322 | * with an INIT chunk that is bundled with other chunks. | |
323 | */ | |
324 | if (!chunk->singleton) | |
24cb81a6 | 325 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
326 | |
327 | /* If the packet is an OOTB packet which is temporarily on the | |
328 | * control endpoint, respond with an ABORT. | |
329 | */ | |
2ce95503 | 330 | if (ep == sctp_sk(net->sctp.ctl_sock)->ep) { |
b01a2407 | 331 | SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES); |
24cb81a6 | 332 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
8190f89d | 333 | } |
1da177e4 | 334 | |
1da177e4 | 335 | /* 3.1 A packet containing an INIT chunk MUST have a zero Verification |
d808ad9a | 336 | * Tag. |
1da177e4 LT |
337 | */ |
338 | if (chunk->sctp_hdr->vtag != 0) | |
24cb81a6 | 339 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
340 | |
341 | /* Make sure that the INIT chunk has a valid length. | |
342 | * Normally, this would cause an ABORT with a Protocol Violation | |
343 | * error, but since we don't have an association, we'll | |
344 | * just discard the packet. | |
345 | */ | |
346 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t))) | |
24cb81a6 | 347 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 348 | |
bec9640b VY |
349 | /* If the INIT is coming toward a closing socket, we'll send back |
350 | * and ABORT. Essentially, this catches the race of INIT being | |
351 | * backloged to the socket at the same time as the user isses close(). | |
352 | * Since the socket and all its associations are going away, we | |
353 | * can treat this OOTB | |
354 | */ | |
355 | if (sctp_sstate(ep->base.sk, CLOSING)) | |
24cb81a6 | 356 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
bec9640b | 357 | |
1da177e4 LT |
358 | /* Verify the INIT chunk before processing it. */ |
359 | err_chunk = NULL; | |
b14878cc | 360 | if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type, |
1da177e4 LT |
361 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, |
362 | &err_chunk)) { | |
363 | /* This chunk contains fatal error. It is to be discarded. | |
364 | * Send an ABORT, with causes if there is any. | |
365 | */ | |
366 | if (err_chunk) { | |
24cb81a6 | 367 | packet = sctp_abort_pkt_new(net, ep, asoc, arg, |
1da177e4 LT |
368 | (__u8 *)(err_chunk->chunk_hdr) + |
369 | sizeof(sctp_chunkhdr_t), | |
370 | ntohs(err_chunk->chunk_hdr->length) - | |
371 | sizeof(sctp_chunkhdr_t)); | |
372 | ||
373 | sctp_chunk_free(err_chunk); | |
374 | ||
375 | if (packet) { | |
376 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
377 | SCTP_PACKET(packet)); | |
b01a2407 | 378 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
379 | return SCTP_DISPOSITION_CONSUME; |
380 | } else { | |
381 | return SCTP_DISPOSITION_NOMEM; | |
382 | } | |
383 | } else { | |
24cb81a6 | 384 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, |
1da177e4 LT |
385 | commands); |
386 | } | |
387 | } | |
388 | ||
d808ad9a | 389 | /* Grab the INIT header. */ |
1da177e4 LT |
390 | chunk->subh.init_hdr = (sctp_inithdr_t *)chunk->skb->data; |
391 | ||
392 | /* Tag the variable length parameters. */ | |
393 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
394 | ||
395 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
396 | if (!new_asoc) | |
397 | goto nomem; | |
398 | ||
409b95af VY |
399 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, |
400 | sctp_scope(sctp_source(chunk)), | |
401 | GFP_ATOMIC) < 0) | |
402 | goto nomem_init; | |
403 | ||
1da177e4 | 404 | /* The call, sctp_process_init(), can fail on memory allocation. */ |
de6becdc | 405 | if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), |
1da177e4 LT |
406 | (sctp_init_chunk_t *)chunk->chunk_hdr, |
407 | GFP_ATOMIC)) | |
408 | goto nomem_init; | |
409 | ||
1da177e4 LT |
410 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ |
411 | ||
412 | /* If there are errors need to be reported for unknown parameters, | |
413 | * make sure to reserve enough room in the INIT ACK for them. | |
414 | */ | |
415 | len = 0; | |
416 | if (err_chunk) | |
417 | len = ntohs(err_chunk->chunk_hdr->length) - | |
418 | sizeof(sctp_chunkhdr_t); | |
419 | ||
1da177e4 LT |
420 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); |
421 | if (!repl) | |
df7deeb5 | 422 | goto nomem_init; |
1da177e4 LT |
423 | |
424 | /* If there are errors need to be reported for unknown parameters, | |
425 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
426 | * parameter. | |
427 | */ | |
428 | if (err_chunk) { | |
429 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
430 | * ERROR chunk generated by sctp_verify_init(). Since the | |
431 | * error cause code for "unknown parameter" and the | |
432 | * "Unrecognized parameter" type is the same, we can | |
433 | * construct the parameters in INIT ACK by copying the | |
434 | * ERROR causes over. | |
435 | */ | |
436 | unk_param = (sctp_unrecognized_param_t *) | |
437 | ((__u8 *)(err_chunk->chunk_hdr) + | |
438 | sizeof(sctp_chunkhdr_t)); | |
439 | /* Replace the cause code with the "Unrecognized parameter" | |
440 | * parameter type. | |
441 | */ | |
442 | sctp_addto_chunk(repl, len, unk_param); | |
443 | sctp_chunk_free(err_chunk); | |
444 | } | |
445 | ||
df7deeb5 VY |
446 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); |
447 | ||
1da177e4 LT |
448 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
449 | ||
450 | /* | |
451 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
452 | * "Z" MUST NOT allocate any resources, nor keep any states for the | |
453 | * new association. Otherwise, "Z" will be vulnerable to resource | |
454 | * attacks. | |
455 | */ | |
456 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
457 | ||
458 | return SCTP_DISPOSITION_DELETE_TCB; | |
459 | ||
1da177e4 LT |
460 | nomem_init: |
461 | sctp_association_free(new_asoc); | |
462 | nomem: | |
df7deeb5 VY |
463 | if (err_chunk) |
464 | sctp_chunk_free(err_chunk); | |
1da177e4 LT |
465 | return SCTP_DISPOSITION_NOMEM; |
466 | } | |
467 | ||
468 | /* | |
469 | * Respond to a normal INIT ACK chunk. | |
470 | * We are the side that is initiating the association. | |
471 | * | |
472 | * Section: 5.1 Normal Establishment of an Association, C | |
473 | * C) Upon reception of the INIT ACK from "Z", "A" shall stop the T1-init | |
474 | * timer and leave COOKIE-WAIT state. "A" shall then send the State | |
475 | * Cookie received in the INIT ACK chunk in a COOKIE ECHO chunk, start | |
476 | * the T1-cookie timer, and enter the COOKIE-ECHOED state. | |
477 | * | |
478 | * Note: The COOKIE ECHO chunk can be bundled with any pending outbound | |
479 | * DATA chunks, but it MUST be the first chunk in the packet and | |
480 | * until the COOKIE ACK is returned the sender MUST NOT send any | |
481 | * other packets to the peer. | |
482 | * | |
483 | * Verification Tag: 3.3.3 | |
484 | * If the value of the Initiate Tag in a received INIT ACK chunk is | |
485 | * found to be 0, the receiver MUST treat it as an error and close the | |
486 | * association by transmitting an ABORT. | |
487 | * | |
488 | * Inputs | |
489 | * (endpoint, asoc, chunk) | |
490 | * | |
491 | * Outputs | |
492 | * (asoc, reply_msg, msg_up, timers, counters) | |
493 | * | |
494 | * The return value is the disposition of the chunk. | |
495 | */ | |
24cb81a6 EB |
496 | sctp_disposition_t sctp_sf_do_5_1C_ack(struct net *net, |
497 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
498 | const struct sctp_association *asoc, |
499 | const sctp_subtype_t type, | |
500 | void *arg, | |
501 | sctp_cmd_seq_t *commands) | |
502 | { | |
503 | struct sctp_chunk *chunk = arg; | |
504 | sctp_init_chunk_t *initchunk; | |
1da177e4 LT |
505 | struct sctp_chunk *err_chunk; |
506 | struct sctp_packet *packet; | |
1da177e4 LT |
507 | |
508 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 509 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 510 | |
1da177e4 LT |
511 | /* 6.10 Bundling |
512 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
513 | * SHUTDOWN COMPLETE with any other chunks. | |
514 | */ | |
515 | if (!chunk->singleton) | |
24cb81a6 | 516 | return sctp_sf_violation_chunk(net, ep, asoc, type, arg, commands); |
1da177e4 | 517 | |
ece25dfa VY |
518 | /* Make sure that the INIT-ACK chunk has a valid length */ |
519 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_initack_chunk_t))) | |
24cb81a6 | 520 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa | 521 | commands); |
1da177e4 LT |
522 | /* Grab the INIT header. */ |
523 | chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data; | |
524 | ||
1da177e4 LT |
525 | /* Verify the INIT chunk before processing it. */ |
526 | err_chunk = NULL; | |
b14878cc | 527 | if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type, |
1da177e4 LT |
528 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, |
529 | &err_chunk)) { | |
530 | ||
853f4b50 VY |
531 | sctp_error_t error = SCTP_ERROR_NO_RESOURCE; |
532 | ||
1da177e4 | 533 | /* This chunk contains fatal error. It is to be discarded. |
d6701191 VY |
534 | * Send an ABORT, with causes. If there are no causes, |
535 | * then there wasn't enough memory. Just terminate | |
536 | * the association. | |
1da177e4 LT |
537 | */ |
538 | if (err_chunk) { | |
24cb81a6 | 539 | packet = sctp_abort_pkt_new(net, ep, asoc, arg, |
1da177e4 LT |
540 | (__u8 *)(err_chunk->chunk_hdr) + |
541 | sizeof(sctp_chunkhdr_t), | |
542 | ntohs(err_chunk->chunk_hdr->length) - | |
543 | sizeof(sctp_chunkhdr_t)); | |
544 | ||
545 | sctp_chunk_free(err_chunk); | |
546 | ||
547 | if (packet) { | |
548 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
549 | SCTP_PACKET(packet)); | |
24cb81a6 | 550 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
8de8c873 | 551 | error = SCTP_ERROR_INV_PARAM; |
1da177e4 | 552 | } |
1da177e4 | 553 | } |
bbd0d598 VY |
554 | |
555 | /* SCTP-AUTH, Section 6.3: | |
556 | * It should be noted that if the receiver wants to tear | |
557 | * down an association in an authenticated way only, the | |
558 | * handling of malformed packets should not result in | |
559 | * tearing down the association. | |
560 | * | |
561 | * This means that if we only want to abort associations | |
562 | * in an authenticated way (i.e AUTH+ABORT), then we | |
25985edc | 563 | * can't destroy this association just because the packet |
bbd0d598 VY |
564 | * was malformed. |
565 | */ | |
566 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) | |
24cb81a6 | 567 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
bbd0d598 | 568 | |
24cb81a6 EB |
569 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
570 | return sctp_stop_t1_and_abort(net, commands, error, ECONNREFUSED, | |
8de8c873 | 571 | asoc, chunk->transport); |
1da177e4 LT |
572 | } |
573 | ||
574 | /* Tag the variable length parameters. Note that we never | |
575 | * convert the parameters in an INIT chunk. | |
576 | */ | |
577 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
578 | ||
579 | initchunk = (sctp_init_chunk_t *) chunk->chunk_hdr; | |
580 | ||
581 | sctp_add_cmd_sf(commands, SCTP_CMD_PEER_INIT, | |
582 | SCTP_PEER_INIT(initchunk)); | |
583 | ||
3f7a87d2 FF |
584 | /* Reset init error count upon receipt of INIT-ACK. */ |
585 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); | |
586 | ||
1da177e4 LT |
587 | /* 5.1 C) "A" shall stop the T1-init timer and leave |
588 | * COOKIE-WAIT state. "A" shall then ... start the T1-cookie | |
589 | * timer, and enter the COOKIE-ECHOED state. | |
590 | */ | |
591 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
592 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
593 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
594 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
595 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
596 | SCTP_STATE(SCTP_STATE_COOKIE_ECHOED)); | |
597 | ||
730fc3d0 VY |
598 | /* SCTP-AUTH: genereate the assocition shared keys so that |
599 | * we can potentially signe the COOKIE-ECHO. | |
600 | */ | |
601 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_SHKEY, SCTP_NULL()); | |
602 | ||
1da177e4 LT |
603 | /* 5.1 C) "A" shall then send the State Cookie received in the |
604 | * INIT ACK chunk in a COOKIE ECHO chunk, ... | |
605 | */ | |
606 | /* If there is any errors to report, send the ERROR chunk generated | |
607 | * for unknown parameters as well. | |
608 | */ | |
609 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_COOKIE_ECHO, | |
610 | SCTP_CHUNK(err_chunk)); | |
611 | ||
612 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
613 | } |
614 | ||
615 | /* | |
616 | * Respond to a normal COOKIE ECHO chunk. | |
617 | * We are the side that is being asked for an association. | |
618 | * | |
619 | * Section: 5.1 Normal Establishment of an Association, D | |
620 | * D) Upon reception of the COOKIE ECHO chunk, Endpoint "Z" will reply | |
621 | * with a COOKIE ACK chunk after building a TCB and moving to | |
622 | * the ESTABLISHED state. A COOKIE ACK chunk may be bundled with | |
623 | * any pending DATA chunks (and/or SACK chunks), but the COOKIE ACK | |
624 | * chunk MUST be the first chunk in the packet. | |
625 | * | |
626 | * IMPLEMENTATION NOTE: An implementation may choose to send the | |
627 | * Communication Up notification to the SCTP user upon reception | |
628 | * of a valid COOKIE ECHO chunk. | |
629 | * | |
630 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
631 | * D) Rules for packet carrying a COOKIE ECHO | |
632 | * | |
633 | * - When sending a COOKIE ECHO, the endpoint MUST use the value of the | |
634 | * Initial Tag received in the INIT ACK. | |
635 | * | |
636 | * - The receiver of a COOKIE ECHO follows the procedures in Section 5. | |
637 | * | |
638 | * Inputs | |
639 | * (endpoint, asoc, chunk) | |
640 | * | |
641 | * Outputs | |
642 | * (asoc, reply_msg, msg_up, timers, counters) | |
643 | * | |
644 | * The return value is the disposition of the chunk. | |
645 | */ | |
24cb81a6 EB |
646 | sctp_disposition_t sctp_sf_do_5_1D_ce(struct net *net, |
647 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
648 | const struct sctp_association *asoc, |
649 | const sctp_subtype_t type, void *arg, | |
650 | sctp_cmd_seq_t *commands) | |
651 | { | |
652 | struct sctp_chunk *chunk = arg; | |
653 | struct sctp_association *new_asoc; | |
654 | sctp_init_chunk_t *peer_init; | |
655 | struct sctp_chunk *repl; | |
df7deeb5 | 656 | struct sctp_ulpevent *ev, *ai_ev = NULL; |
1da177e4 LT |
657 | int error = 0; |
658 | struct sctp_chunk *err_chk_p; | |
609ee467 | 659 | struct sock *sk; |
1da177e4 LT |
660 | |
661 | /* If the packet is an OOTB packet which is temporarily on the | |
662 | * control endpoint, respond with an ABORT. | |
663 | */ | |
2ce95503 | 664 | if (ep == sctp_sk(net->sctp.ctl_sock)->ep) { |
b01a2407 | 665 | SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES); |
24cb81a6 | 666 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
8190f89d | 667 | } |
1da177e4 LT |
668 | |
669 | /* Make sure that the COOKIE_ECHO chunk has a valid length. | |
670 | * In this case, we check that we have enough for at least a | |
671 | * chunk header. More detailed verification is done | |
672 | * in sctp_unpack_cookie(). | |
673 | */ | |
674 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 675 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 676 | |
609ee467 VY |
677 | /* If the endpoint is not listening or if the number of associations |
678 | * on the TCP-style socket exceed the max backlog, respond with an | |
679 | * ABORT. | |
680 | */ | |
681 | sk = ep->base.sk; | |
682 | if (!sctp_sstate(sk, LISTENING) || | |
683 | (sctp_style(sk, TCP) && sk_acceptq_is_full(sk))) | |
24cb81a6 | 684 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
609ee467 | 685 | |
1da177e4 LT |
686 | /* "Decode" the chunk. We have no optional parameters so we |
687 | * are in good shape. | |
688 | */ | |
d808ad9a | 689 | chunk->subh.cookie_hdr = |
1da177e4 | 690 | (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 SS |
691 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
692 | sizeof(sctp_chunkhdr_t))) | |
693 | goto nomem; | |
1da177e4 LT |
694 | |
695 | /* 5.1 D) Upon reception of the COOKIE ECHO chunk, Endpoint | |
696 | * "Z" will reply with a COOKIE ACK chunk after building a TCB | |
697 | * and moving to the ESTABLISHED state. | |
698 | */ | |
699 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
700 | &err_chk_p); | |
701 | ||
702 | /* FIXME: | |
703 | * If the re-build failed, what is the proper error path | |
704 | * from here? | |
705 | * | |
706 | * [We should abort the association. --piggy] | |
707 | */ | |
708 | if (!new_asoc) { | |
709 | /* FIXME: Several errors are possible. A bad cookie should | |
710 | * be silently discarded, but think about logging it too. | |
711 | */ | |
712 | switch (error) { | |
713 | case -SCTP_IERROR_NOMEM: | |
714 | goto nomem; | |
715 | ||
716 | case -SCTP_IERROR_STALE_COOKIE: | |
24cb81a6 | 717 | sctp_send_stale_cookie_err(net, ep, asoc, chunk, commands, |
1da177e4 | 718 | err_chk_p); |
24cb81a6 | 719 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
720 | |
721 | case -SCTP_IERROR_BAD_SIG: | |
722 | default: | |
24cb81a6 | 723 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
3ff50b79 | 724 | } |
1da177e4 LT |
725 | } |
726 | ||
1da177e4 | 727 | |
df7deeb5 VY |
728 | /* Delay state machine commands until later. |
729 | * | |
730 | * Re-build the bind address for the association is done in | |
1da177e4 LT |
731 | * the sctp_unpack_cookie() already. |
732 | */ | |
733 | /* This is a brand-new association, so these are not yet side | |
734 | * effects--it is safe to run them here. | |
735 | */ | |
736 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
737 | ||
de6becdc | 738 | if (!sctp_process_init(new_asoc, chunk, |
6a1e5f33 | 739 | &chunk->subh.cookie_hdr->c.peer_addr, |
1da177e4 LT |
740 | peer_init, GFP_ATOMIC)) |
741 | goto nomem_init; | |
742 | ||
730fc3d0 VY |
743 | /* SCTP-AUTH: Now that we've populate required fields in |
744 | * sctp_process_init, set up the assocaition shared keys as | |
745 | * necessary so that we can potentially authenticate the ACK | |
746 | */ | |
747 | error = sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC); | |
748 | if (error) | |
749 | goto nomem_init; | |
750 | ||
bbd0d598 VY |
751 | /* SCTP-AUTH: auth_chunk pointer is only set when the cookie-echo |
752 | * is supposed to be authenticated and we have to do delayed | |
753 | * authentication. We've just recreated the association using | |
754 | * the information in the cookie and now it's much easier to | |
755 | * do the authentication. | |
756 | */ | |
757 | if (chunk->auth_chunk) { | |
758 | struct sctp_chunk auth; | |
759 | sctp_ierror_t ret; | |
760 | ||
ec0223ec DB |
761 | /* Make sure that we and the peer are AUTH capable */ |
762 | if (!net->sctp.auth_enable || !new_asoc->peer.auth_capable) { | |
ec0223ec DB |
763 | sctp_association_free(new_asoc); |
764 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); | |
765 | } | |
766 | ||
bbd0d598 VY |
767 | /* set-up our fake chunk so that we can process it */ |
768 | auth.skb = chunk->auth_chunk; | |
769 | auth.asoc = chunk->asoc; | |
770 | auth.sctp_hdr = chunk->sctp_hdr; | |
771 | auth.chunk_hdr = (sctp_chunkhdr_t *)skb_push(chunk->auth_chunk, | |
772 | sizeof(sctp_chunkhdr_t)); | |
773 | skb_pull(chunk->auth_chunk, sizeof(sctp_chunkhdr_t)); | |
774 | auth.transport = chunk->transport; | |
775 | ||
24cb81a6 | 776 | ret = sctp_sf_authenticate(net, ep, new_asoc, type, &auth); |
bbd0d598 VY |
777 | if (ret != SCTP_IERROR_NO_ERROR) { |
778 | sctp_association_free(new_asoc); | |
24cb81a6 | 779 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
bbd0d598 VY |
780 | } |
781 | } | |
782 | ||
1da177e4 LT |
783 | repl = sctp_make_cookie_ack(new_asoc, chunk); |
784 | if (!repl) | |
df7deeb5 | 785 | goto nomem_init; |
1da177e4 LT |
786 | |
787 | /* RFC 2960 5.1 Normal Establishment of an Association | |
788 | * | |
789 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
790 | * send the Communication Up notification to the SCTP user | |
791 | * upon reception of a valid COOKIE ECHO chunk. | |
792 | */ | |
793 | ev = sctp_ulpevent_make_assoc_change(new_asoc, 0, SCTP_COMM_UP, 0, | |
794 | new_asoc->c.sinit_num_ostreams, | |
795 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 796 | NULL, GFP_ATOMIC); |
1da177e4 LT |
797 | if (!ev) |
798 | goto nomem_ev; | |
799 | ||
d808ad9a | 800 | /* Sockets API Draft Section 5.3.1.6 |
0f3fffd8 | 801 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 802 | * delivers this notification to inform the application that of the |
0f3fffd8 | 803 | * peers requested adaptation layer. |
1da177e4 | 804 | */ |
0f3fffd8 ISJ |
805 | if (new_asoc->peer.adaptation_ind) { |
806 | ai_ev = sctp_ulpevent_make_adaptation_indication(new_asoc, | |
1da177e4 | 807 | GFP_ATOMIC); |
df7deeb5 VY |
808 | if (!ai_ev) |
809 | goto nomem_aiev; | |
810 | } | |
811 | ||
812 | /* Add all the state machine commands now since we've created | |
813 | * everything. This way we don't introduce memory corruptions | |
814 | * during side-effect processing and correclty count established | |
815 | * associations. | |
816 | */ | |
817 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
818 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
819 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
b01a2407 EB |
820 | SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB); |
821 | SCTP_INC_STATS(net, SCTP_MIB_PASSIVEESTABS); | |
df7deeb5 VY |
822 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); |
823 | ||
9f70f46b | 824 | if (new_asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) |
df7deeb5 VY |
825 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, |
826 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
827 | ||
df7deeb5 VY |
828 | /* This will send the COOKIE ACK */ |
829 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
830 | ||
831 | /* Queue the ASSOC_CHANGE event */ | |
832 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
833 | ||
834 | /* Send up the Adaptation Layer Indication event */ | |
835 | if (ai_ev) | |
1da177e4 | 836 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, |
df7deeb5 | 837 | SCTP_ULPEVENT(ai_ev)); |
1da177e4 LT |
838 | |
839 | return SCTP_DISPOSITION_CONSUME; | |
840 | ||
df7deeb5 VY |
841 | nomem_aiev: |
842 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
843 | nomem_ev: |
844 | sctp_chunk_free(repl); | |
1da177e4 LT |
845 | nomem_init: |
846 | sctp_association_free(new_asoc); | |
847 | nomem: | |
848 | return SCTP_DISPOSITION_NOMEM; | |
849 | } | |
850 | ||
851 | /* | |
852 | * Respond to a normal COOKIE ACK chunk. | |
853 | * We are the side that is being asked for an association. | |
854 | * | |
855 | * RFC 2960 5.1 Normal Establishment of an Association | |
856 | * | |
857 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move from the | |
858 | * COOKIE-ECHOED state to the ESTABLISHED state, stopping the T1-cookie | |
859 | * timer. It may also notify its ULP about the successful | |
860 | * establishment of the association with a Communication Up | |
861 | * notification (see Section 10). | |
862 | * | |
863 | * Verification Tag: | |
864 | * Inputs | |
865 | * (endpoint, asoc, chunk) | |
866 | * | |
867 | * Outputs | |
868 | * (asoc, reply_msg, msg_up, timers, counters) | |
869 | * | |
870 | * The return value is the disposition of the chunk. | |
871 | */ | |
24cb81a6 EB |
872 | sctp_disposition_t sctp_sf_do_5_1E_ca(struct net *net, |
873 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
874 | const struct sctp_association *asoc, |
875 | const sctp_subtype_t type, void *arg, | |
876 | sctp_cmd_seq_t *commands) | |
877 | { | |
878 | struct sctp_chunk *chunk = arg; | |
879 | struct sctp_ulpevent *ev; | |
880 | ||
881 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 882 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
883 | |
884 | /* Verify that the chunk length for the COOKIE-ACK is OK. | |
885 | * If we don't do this, any bundled chunks may be junked. | |
886 | */ | |
887 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 888 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
889 | commands); |
890 | ||
891 | /* Reset init error count upon receipt of COOKIE-ACK, | |
892 | * to avoid problems with the managemement of this | |
893 | * counter in stale cookie situations when a transition back | |
894 | * from the COOKIE-ECHOED state to the COOKIE-WAIT | |
895 | * state is performed. | |
896 | */ | |
3f7a87d2 | 897 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); |
1da177e4 LT |
898 | |
899 | /* RFC 2960 5.1 Normal Establishment of an Association | |
900 | * | |
901 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move | |
902 | * from the COOKIE-ECHOED state to the ESTABLISHED state, | |
903 | * stopping the T1-cookie timer. | |
904 | */ | |
905 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
906 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
907 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
908 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
b01a2407 EB |
909 | SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB); |
910 | SCTP_INC_STATS(net, SCTP_MIB_ACTIVEESTABS); | |
1da177e4 | 911 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); |
9f70f46b | 912 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) |
1da177e4 LT |
913 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, |
914 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
1da177e4 LT |
915 | |
916 | /* It may also notify its ULP about the successful | |
917 | * establishment of the association with a Communication Up | |
918 | * notification (see Section 10). | |
919 | */ | |
920 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_UP, | |
921 | 0, asoc->c.sinit_num_ostreams, | |
922 | asoc->c.sinit_max_instreams, | |
a5a35e76 | 923 | NULL, GFP_ATOMIC); |
1da177e4 LT |
924 | |
925 | if (!ev) | |
926 | goto nomem; | |
927 | ||
928 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
929 | ||
930 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 931 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 932 | * delivers this notification to inform the application that of the |
0f3fffd8 | 933 | * peers requested adaptation layer. |
1da177e4 | 934 | */ |
0f3fffd8 ISJ |
935 | if (asoc->peer.adaptation_ind) { |
936 | ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC); | |
1da177e4 LT |
937 | if (!ev) |
938 | goto nomem; | |
939 | ||
940 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
941 | SCTP_ULPEVENT(ev)); | |
942 | } | |
943 | ||
944 | return SCTP_DISPOSITION_CONSUME; | |
945 | nomem: | |
946 | return SCTP_DISPOSITION_NOMEM; | |
947 | } | |
948 | ||
949 | /* Generate and sendout a heartbeat packet. */ | |
950 | static sctp_disposition_t sctp_sf_heartbeat(const struct sctp_endpoint *ep, | |
951 | const struct sctp_association *asoc, | |
952 | const sctp_subtype_t type, | |
953 | void *arg, | |
954 | sctp_cmd_seq_t *commands) | |
955 | { | |
956 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
957 | struct sctp_chunk *reply; | |
1da177e4 LT |
958 | |
959 | /* Send a heartbeat to our peer. */ | |
92c73af5 | 960 | reply = sctp_make_heartbeat(asoc, transport); |
1da177e4 LT |
961 | if (!reply) |
962 | return SCTP_DISPOSITION_NOMEM; | |
963 | ||
964 | /* Set rto_pending indicating that an RTT measurement | |
965 | * is started with this heartbeat chunk. | |
966 | */ | |
967 | sctp_add_cmd_sf(commands, SCTP_CMD_RTO_PENDING, | |
968 | SCTP_TRANSPORT(transport)); | |
969 | ||
970 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
971 | return SCTP_DISPOSITION_CONSUME; | |
972 | } | |
973 | ||
974 | /* Generate a HEARTBEAT packet on the given transport. */ | |
24cb81a6 EB |
975 | sctp_disposition_t sctp_sf_sendbeat_8_3(struct net *net, |
976 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
977 | const struct sctp_association *asoc, |
978 | const sctp_subtype_t type, | |
979 | void *arg, | |
980 | sctp_cmd_seq_t *commands) | |
981 | { | |
982 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
983 | ||
b9f84786 | 984 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
985 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
986 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
987 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
988 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 989 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
b01a2407 EB |
990 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
991 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
992 | return SCTP_DISPOSITION_DELETE_TCB; |
993 | } | |
994 | ||
995 | /* Section 3.3.5. | |
996 | * The Sender-specific Heartbeat Info field should normally include | |
997 | * information about the sender's current time when this HEARTBEAT | |
998 | * chunk is sent and the destination transport address to which this | |
999 | * HEARTBEAT is sent (see Section 8.3). | |
1000 | */ | |
1001 | ||
52ccb8e9 | 1002 | if (transport->param_flags & SPP_HB_ENABLE) { |
1da177e4 LT |
1003 | if (SCTP_DISPOSITION_NOMEM == |
1004 | sctp_sf_heartbeat(ep, asoc, type, arg, | |
1005 | commands)) | |
1006 | return SCTP_DISPOSITION_NOMEM; | |
245cba7e | 1007 | |
1da177e4 LT |
1008 | /* Set transport error counter and association error counter |
1009 | * when sending heartbeat. | |
1010 | */ | |
7e99013a | 1011 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_HB_SENT, |
1da177e4 LT |
1012 | SCTP_TRANSPORT(transport)); |
1013 | } | |
245cba7e VY |
1014 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_IDLE, |
1015 | SCTP_TRANSPORT(transport)); | |
1da177e4 LT |
1016 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMER_UPDATE, |
1017 | SCTP_TRANSPORT(transport)); | |
1018 | ||
d808ad9a | 1019 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
1020 | } |
1021 | ||
1022 | /* | |
1023 | * Process an heartbeat request. | |
1024 | * | |
1025 | * Section: 8.3 Path Heartbeat | |
1026 | * The receiver of the HEARTBEAT should immediately respond with a | |
1027 | * HEARTBEAT ACK that contains the Heartbeat Information field copied | |
1028 | * from the received HEARTBEAT chunk. | |
1029 | * | |
1030 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
1031 | * When receiving an SCTP packet, the endpoint MUST ensure that the | |
1032 | * value in the Verification Tag field of the received SCTP packet | |
1033 | * matches its own Tag. If the received Verification Tag value does not | |
1034 | * match the receiver's own tag value, the receiver shall silently | |
1035 | * discard the packet and shall not process it any further except for | |
1036 | * those cases listed in Section 8.5.1 below. | |
1037 | * | |
1038 | * Inputs | |
1039 | * (endpoint, asoc, chunk) | |
1040 | * | |
1041 | * Outputs | |
1042 | * (asoc, reply_msg, msg_up, timers, counters) | |
1043 | * | |
1044 | * The return value is the disposition of the chunk. | |
1045 | */ | |
24cb81a6 EB |
1046 | sctp_disposition_t sctp_sf_beat_8_3(struct net *net, |
1047 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
1048 | const struct sctp_association *asoc, |
1049 | const sctp_subtype_t type, | |
1050 | void *arg, | |
1051 | sctp_cmd_seq_t *commands) | |
1052 | { | |
06a31e2b | 1053 | sctp_paramhdr_t *param_hdr; |
1da177e4 LT |
1054 | struct sctp_chunk *chunk = arg; |
1055 | struct sctp_chunk *reply; | |
1056 | size_t paylen = 0; | |
1057 | ||
1058 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 1059 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1060 | |
1061 | /* Make sure that the HEARTBEAT chunk has a valid length. */ | |
1062 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_heartbeat_chunk_t))) | |
24cb81a6 | 1063 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
1064 | commands); |
1065 | ||
1066 | /* 8.3 The receiver of the HEARTBEAT should immediately | |
1067 | * respond with a HEARTBEAT ACK that contains the Heartbeat | |
1068 | * Information field copied from the received HEARTBEAT chunk. | |
1069 | */ | |
1070 | chunk->subh.hb_hdr = (sctp_heartbeathdr_t *) chunk->skb->data; | |
06a31e2b | 1071 | param_hdr = (sctp_paramhdr_t *) chunk->subh.hb_hdr; |
1da177e4 | 1072 | paylen = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_chunkhdr_t); |
06a31e2b TG |
1073 | |
1074 | if (ntohs(param_hdr->length) > paylen) | |
1075 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, | |
1076 | param_hdr, commands); | |
1077 | ||
62b08083 SS |
1078 | if (!pskb_pull(chunk->skb, paylen)) |
1079 | goto nomem; | |
1da177e4 | 1080 | |
06a31e2b | 1081 | reply = sctp_make_heartbeat_ack(asoc, chunk, param_hdr, paylen); |
1da177e4 LT |
1082 | if (!reply) |
1083 | goto nomem; | |
1084 | ||
1085 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
1086 | return SCTP_DISPOSITION_CONSUME; | |
1087 | ||
1088 | nomem: | |
1089 | return SCTP_DISPOSITION_NOMEM; | |
1090 | } | |
1091 | ||
1092 | /* | |
1093 | * Process the returning HEARTBEAT ACK. | |
1094 | * | |
1095 | * Section: 8.3 Path Heartbeat | |
1096 | * Upon the receipt of the HEARTBEAT ACK, the sender of the HEARTBEAT | |
1097 | * should clear the error counter of the destination transport | |
1098 | * address to which the HEARTBEAT was sent, and mark the destination | |
1099 | * transport address as active if it is not so marked. The endpoint may | |
1100 | * optionally report to the upper layer when an inactive destination | |
1101 | * address is marked as active due to the reception of the latest | |
1102 | * HEARTBEAT ACK. The receiver of the HEARTBEAT ACK must also | |
1103 | * clear the association overall error count as well (as defined | |
1104 | * in section 8.1). | |
1105 | * | |
1106 | * The receiver of the HEARTBEAT ACK should also perform an RTT | |
1107 | * measurement for that destination transport address using the time | |
1108 | * value carried in the HEARTBEAT ACK chunk. | |
1109 | * | |
1110 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
1111 | * | |
1112 | * Inputs | |
1113 | * (endpoint, asoc, chunk) | |
1114 | * | |
1115 | * Outputs | |
1116 | * (asoc, reply_msg, msg_up, timers, counters) | |
1117 | * | |
1118 | * The return value is the disposition of the chunk. | |
1119 | */ | |
24cb81a6 EB |
1120 | sctp_disposition_t sctp_sf_backbeat_8_3(struct net *net, |
1121 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
1122 | const struct sctp_association *asoc, |
1123 | const sctp_subtype_t type, | |
1124 | void *arg, | |
1125 | sctp_cmd_seq_t *commands) | |
1126 | { | |
1127 | struct sctp_chunk *chunk = arg; | |
1128 | union sctp_addr from_addr; | |
1129 | struct sctp_transport *link; | |
1130 | sctp_sender_hb_info_t *hbinfo; | |
1131 | unsigned long max_interval; | |
1132 | ||
1133 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 1134 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1135 | |
1136 | /* Make sure that the HEARTBEAT-ACK chunk has a valid length. */ | |
dadb50cc WY |
1137 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t) + |
1138 | sizeof(sctp_sender_hb_info_t))) | |
24cb81a6 | 1139 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
1140 | commands); |
1141 | ||
1142 | hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; | |
a601266e VY |
1143 | /* Make sure that the length of the parameter is what we expect */ |
1144 | if (ntohs(hbinfo->param_hdr.length) != | |
1145 | sizeof(sctp_sender_hb_info_t)) { | |
1146 | return SCTP_DISPOSITION_DISCARD; | |
1147 | } | |
1148 | ||
1da177e4 | 1149 | from_addr = hbinfo->daddr; |
63de08f4 | 1150 | link = sctp_assoc_lookup_paddr(asoc, &from_addr); |
1da177e4 LT |
1151 | |
1152 | /* This should never happen, but lets log it if so. */ | |
3f7a87d2 FF |
1153 | if (unlikely(!link)) { |
1154 | if (from_addr.sa.sa_family == AF_INET6) { | |
e87cc472 JP |
1155 | net_warn_ratelimited("%s association %p could not find address %pI6\n", |
1156 | __func__, | |
1157 | asoc, | |
1158 | &from_addr.v6.sin6_addr); | |
3f7a87d2 | 1159 | } else { |
e87cc472 JP |
1160 | net_warn_ratelimited("%s association %p could not find address %pI4\n", |
1161 | __func__, | |
1162 | asoc, | |
1163 | &from_addr.v4.sin_addr.s_addr); | |
3f7a87d2 | 1164 | } |
1da177e4 LT |
1165 | return SCTP_DISPOSITION_DISCARD; |
1166 | } | |
1167 | ||
ad8fec17 SS |
1168 | /* Validate the 64-bit random nonce. */ |
1169 | if (hbinfo->hb_nonce != link->hb_nonce) | |
1170 | return SCTP_DISPOSITION_DISCARD; | |
1171 | ||
52ccb8e9 | 1172 | max_interval = link->hbinterval + link->rto; |
1da177e4 LT |
1173 | |
1174 | /* Check if the timestamp looks valid. */ | |
1175 | if (time_after(hbinfo->sent_at, jiffies) || | |
1176 | time_after(jiffies, hbinfo->sent_at + max_interval)) { | |
bb33381d DB |
1177 | pr_debug("%s: HEARTBEAT ACK with invalid timestamp received " |
1178 | "for transport:%p\n", __func__, link); | |
1179 | ||
1da177e4 LT |
1180 | return SCTP_DISPOSITION_DISCARD; |
1181 | } | |
1182 | ||
1183 | /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of | |
1184 | * the HEARTBEAT should clear the error counter of the | |
1185 | * destination transport address to which the HEARTBEAT was | |
1186 | * sent and mark the destination transport address as active if | |
1187 | * it is not so marked. | |
1188 | */ | |
1189 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_ON, SCTP_TRANSPORT(link)); | |
1190 | ||
1191 | return SCTP_DISPOSITION_CONSUME; | |
1192 | } | |
1193 | ||
1194 | /* Helper function to send out an abort for the restart | |
1195 | * condition. | |
1196 | */ | |
2ce95503 | 1197 | static int sctp_sf_send_restart_abort(struct net *net, union sctp_addr *ssa, |
1da177e4 LT |
1198 | struct sctp_chunk *init, |
1199 | sctp_cmd_seq_t *commands) | |
1200 | { | |
1201 | int len; | |
1202 | struct sctp_packet *pkt; | |
1203 | union sctp_addr_param *addrparm; | |
1204 | struct sctp_errhdr *errhdr; | |
1205 | struct sctp_endpoint *ep; | |
1206 | char buffer[sizeof(struct sctp_errhdr)+sizeof(union sctp_addr_param)]; | |
1207 | struct sctp_af *af = sctp_get_af_specific(ssa->v4.sin_family); | |
1208 | ||
1209 | /* Build the error on the stack. We are way to malloc crazy | |
1210 | * throughout the code today. | |
1211 | */ | |
1212 | errhdr = (struct sctp_errhdr *)buffer; | |
1213 | addrparm = (union sctp_addr_param *)errhdr->variable; | |
1214 | ||
1215 | /* Copy into a parm format. */ | |
1216 | len = af->to_addr_param(ssa, addrparm); | |
1217 | len += sizeof(sctp_errhdr_t); | |
1218 | ||
1219 | errhdr->cause = SCTP_ERROR_RESTART; | |
1220 | errhdr->length = htons(len); | |
1221 | ||
1222 | /* Assign to the control socket. */ | |
2ce95503 | 1223 | ep = sctp_sk(net->sctp.ctl_sock)->ep; |
1da177e4 LT |
1224 | |
1225 | /* Association is NULL since this may be a restart attack and we | |
1226 | * want to send back the attacker's vtag. | |
1227 | */ | |
24cb81a6 | 1228 | pkt = sctp_abort_pkt_new(net, ep, NULL, init, errhdr, len); |
1da177e4 LT |
1229 | |
1230 | if (!pkt) | |
1231 | goto out; | |
1232 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, SCTP_PACKET(pkt)); | |
1233 | ||
b01a2407 | 1234 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
1235 | |
1236 | /* Discard the rest of the inbound packet. */ | |
1237 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); | |
1238 | ||
1239 | out: | |
1240 | /* Even if there is no memory, treat as a failure so | |
1241 | * the packet will get dropped. | |
1242 | */ | |
1243 | return 0; | |
1244 | } | |
1245 | ||
123031c0 JP |
1246 | static bool list_has_sctp_addr(const struct list_head *list, |
1247 | union sctp_addr *ipaddr) | |
1248 | { | |
1249 | struct sctp_transport *addr; | |
1250 | ||
1251 | list_for_each_entry(addr, list, transports) { | |
1252 | if (sctp_cmp_addr_exact(ipaddr, &addr->ipaddr)) | |
1253 | return true; | |
1254 | } | |
1255 | ||
1256 | return false; | |
1257 | } | |
1da177e4 LT |
1258 | /* A restart is occurring, check to make sure no new addresses |
1259 | * are being added as we may be under a takeover attack. | |
1260 | */ | |
1261 | static int sctp_sf_check_restart_addrs(const struct sctp_association *new_asoc, | |
1262 | const struct sctp_association *asoc, | |
1263 | struct sctp_chunk *init, | |
1264 | sctp_cmd_seq_t *commands) | |
1265 | { | |
2ce95503 | 1266 | struct net *net = sock_net(new_asoc->base.sk); |
123031c0 JP |
1267 | struct sctp_transport *new_addr; |
1268 | int ret = 1; | |
1da177e4 | 1269 | |
123031c0 | 1270 | /* Implementor's Guide - Section 5.2.2 |
1da177e4 LT |
1271 | * ... |
1272 | * Before responding the endpoint MUST check to see if the | |
1273 | * unexpected INIT adds new addresses to the association. If new | |
1274 | * addresses are added to the association, the endpoint MUST respond | |
1275 | * with an ABORT.. | |
1276 | */ | |
1277 | ||
1278 | /* Search through all current addresses and make sure | |
1279 | * we aren't adding any new ones. | |
1280 | */ | |
9dbc15f0 | 1281 | list_for_each_entry(new_addr, &new_asoc->peer.transport_addr_list, |
123031c0 JP |
1282 | transports) { |
1283 | if (!list_has_sctp_addr(&asoc->peer.transport_addr_list, | |
1284 | &new_addr->ipaddr)) { | |
2ce95503 | 1285 | sctp_sf_send_restart_abort(net, &new_addr->ipaddr, init, |
123031c0 JP |
1286 | commands); |
1287 | ret = 0; | |
1da177e4 | 1288 | break; |
123031c0 | 1289 | } |
1da177e4 LT |
1290 | } |
1291 | ||
1292 | /* Return success if all addresses were found. */ | |
123031c0 | 1293 | return ret; |
1da177e4 LT |
1294 | } |
1295 | ||
1296 | /* Populate the verification/tie tags based on overlapping INIT | |
1297 | * scenario. | |
1298 | * | |
1299 | * Note: Do not use in CLOSED or SHUTDOWN-ACK-SENT state. | |
1300 | */ | |
1301 | static void sctp_tietags_populate(struct sctp_association *new_asoc, | |
1302 | const struct sctp_association *asoc) | |
1303 | { | |
1304 | switch (asoc->state) { | |
1305 | ||
1306 | /* 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State */ | |
1307 | ||
1308 | case SCTP_STATE_COOKIE_WAIT: | |
1309 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1310 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1311 | new_asoc->c.peer_ttag = 0; | |
1312 | break; | |
1313 | ||
1314 | case SCTP_STATE_COOKIE_ECHOED: | |
1315 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1316 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1317 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1318 | break; | |
1319 | ||
1320 | /* 5.2.2 Unexpected INIT in States Other than CLOSED, COOKIE-ECHOED, | |
1321 | * COOKIE-WAIT and SHUTDOWN-ACK-SENT | |
1322 | */ | |
1323 | default: | |
1324 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1325 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1326 | break; | |
3ff50b79 | 1327 | } |
1da177e4 LT |
1328 | |
1329 | /* Other parameters for the endpoint SHOULD be copied from the | |
1330 | * existing parameters of the association (e.g. number of | |
1331 | * outbound streams) into the INIT ACK and cookie. | |
1332 | */ | |
1333 | new_asoc->rwnd = asoc->rwnd; | |
1334 | new_asoc->c.sinit_num_ostreams = asoc->c.sinit_num_ostreams; | |
1335 | new_asoc->c.sinit_max_instreams = asoc->c.sinit_max_instreams; | |
1336 | new_asoc->c.initial_tsn = asoc->c.initial_tsn; | |
1337 | } | |
1338 | ||
1339 | /* | |
1340 | * Compare vtag/tietag values to determine unexpected COOKIE-ECHO | |
1341 | * handling action. | |
1342 | * | |
1343 | * RFC 2960 5.2.4 Handle a COOKIE ECHO when a TCB exists. | |
1344 | * | |
1345 | * Returns value representing action to be taken. These action values | |
1346 | * correspond to Action/Description values in RFC 2960, Table 2. | |
1347 | */ | |
1348 | static char sctp_tietags_compare(struct sctp_association *new_asoc, | |
1349 | const struct sctp_association *asoc) | |
1350 | { | |
1351 | /* In this case, the peer may have restarted. */ | |
1352 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1353 | (asoc->c.peer_vtag != new_asoc->c.peer_vtag) && | |
1354 | (asoc->c.my_vtag == new_asoc->c.my_ttag) && | |
1355 | (asoc->c.peer_vtag == new_asoc->c.peer_ttag)) | |
1356 | return 'A'; | |
1357 | ||
1358 | /* Collision case B. */ | |
1359 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1360 | ((asoc->c.peer_vtag != new_asoc->c.peer_vtag) || | |
1361 | (0 == asoc->c.peer_vtag))) { | |
1362 | return 'B'; | |
1363 | } | |
1364 | ||
1365 | /* Collision case D. */ | |
1366 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1367 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag)) | |
1368 | return 'D'; | |
1369 | ||
1370 | /* Collision case C. */ | |
1371 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1372 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag) && | |
1373 | (0 == new_asoc->c.my_ttag) && | |
1374 | (0 == new_asoc->c.peer_ttag)) | |
1375 | return 'C'; | |
1376 | ||
1377 | /* No match to any of the special cases; discard this packet. */ | |
1378 | return 'E'; | |
1379 | } | |
1380 | ||
1381 | /* Common helper routine for both duplicate and simulataneous INIT | |
1382 | * chunk handling. | |
1383 | */ | |
1384 | static sctp_disposition_t sctp_sf_do_unexpected_init( | |
24cb81a6 | 1385 | struct net *net, |
1da177e4 LT |
1386 | const struct sctp_endpoint *ep, |
1387 | const struct sctp_association *asoc, | |
1388 | const sctp_subtype_t type, | |
1389 | void *arg, sctp_cmd_seq_t *commands) | |
1390 | { | |
1391 | sctp_disposition_t retval; | |
1392 | struct sctp_chunk *chunk = arg; | |
1393 | struct sctp_chunk *repl; | |
1394 | struct sctp_association *new_asoc; | |
1395 | struct sctp_chunk *err_chunk; | |
1396 | struct sctp_packet *packet; | |
1397 | sctp_unrecognized_param_t *unk_param; | |
1398 | int len; | |
1399 | ||
1400 | /* 6.10 Bundling | |
1401 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
1402 | * SHUTDOWN COMPLETE with any other chunks. | |
1403 | * | |
1404 | * IG Section 2.11.2 | |
1405 | * Furthermore, we require that the receiver of an INIT chunk MUST | |
1406 | * enforce these rules by silently discarding an arriving packet | |
1407 | * with an INIT chunk that is bundled with other chunks. | |
1408 | */ | |
1409 | if (!chunk->singleton) | |
24cb81a6 | 1410 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1411 | |
1412 | /* 3.1 A packet containing an INIT chunk MUST have a zero Verification | |
d808ad9a | 1413 | * Tag. |
1da177e4 LT |
1414 | */ |
1415 | if (chunk->sctp_hdr->vtag != 0) | |
24cb81a6 | 1416 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1417 | |
1418 | /* Make sure that the INIT chunk has a valid length. | |
1419 | * In this case, we generate a protocol violation since we have | |
1420 | * an association established. | |
1421 | */ | |
1422 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t))) | |
24cb81a6 | 1423 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
1424 | commands); |
1425 | /* Grab the INIT header. */ | |
1426 | chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data; | |
1427 | ||
1428 | /* Tag the variable length parameters. */ | |
1429 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
1430 | ||
1431 | /* Verify the INIT chunk before processing it. */ | |
1432 | err_chunk = NULL; | |
b14878cc | 1433 | if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type, |
1da177e4 LT |
1434 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, |
1435 | &err_chunk)) { | |
1436 | /* This chunk contains fatal error. It is to be discarded. | |
1437 | * Send an ABORT, with causes if there is any. | |
1438 | */ | |
1439 | if (err_chunk) { | |
24cb81a6 | 1440 | packet = sctp_abort_pkt_new(net, ep, asoc, arg, |
1da177e4 LT |
1441 | (__u8 *)(err_chunk->chunk_hdr) + |
1442 | sizeof(sctp_chunkhdr_t), | |
1443 | ntohs(err_chunk->chunk_hdr->length) - | |
1444 | sizeof(sctp_chunkhdr_t)); | |
1445 | ||
1446 | if (packet) { | |
1447 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
1448 | SCTP_PACKET(packet)); | |
24cb81a6 | 1449 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
1450 | retval = SCTP_DISPOSITION_CONSUME; |
1451 | } else { | |
1452 | retval = SCTP_DISPOSITION_NOMEM; | |
1453 | } | |
1454 | goto cleanup; | |
1455 | } else { | |
24cb81a6 | 1456 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, |
1da177e4 LT |
1457 | commands); |
1458 | } | |
1459 | } | |
1460 | ||
1461 | /* | |
1462 | * Other parameters for the endpoint SHOULD be copied from the | |
1463 | * existing parameters of the association (e.g. number of | |
1464 | * outbound streams) into the INIT ACK and cookie. | |
1465 | * FIXME: We are copying parameters from the endpoint not the | |
1466 | * association. | |
1467 | */ | |
1468 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
1469 | if (!new_asoc) | |
1470 | goto nomem; | |
1471 | ||
409b95af VY |
1472 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, |
1473 | sctp_scope(sctp_source(chunk)), GFP_ATOMIC) < 0) | |
1474 | goto nomem; | |
1475 | ||
1da177e4 LT |
1476 | /* In the outbound INIT ACK the endpoint MUST copy its current |
1477 | * Verification Tag and Peers Verification tag into a reserved | |
1478 | * place (local tie-tag and per tie-tag) within the state cookie. | |
1479 | */ | |
de6becdc | 1480 | if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), |
1da177e4 | 1481 | (sctp_init_chunk_t *)chunk->chunk_hdr, |
df7deeb5 VY |
1482 | GFP_ATOMIC)) |
1483 | goto nomem; | |
1da177e4 LT |
1484 | |
1485 | /* Make sure no new addresses are being added during the | |
1486 | * restart. Do not do this check for COOKIE-WAIT state, | |
1487 | * since there are no peer addresses to check against. | |
1488 | * Upon return an ABORT will have been sent if needed. | |
1489 | */ | |
1490 | if (!sctp_state(asoc, COOKIE_WAIT)) { | |
1491 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, | |
1492 | commands)) { | |
1493 | retval = SCTP_DISPOSITION_CONSUME; | |
df7deeb5 | 1494 | goto nomem_retval; |
1da177e4 LT |
1495 | } |
1496 | } | |
1497 | ||
1498 | sctp_tietags_populate(new_asoc, asoc); | |
1499 | ||
1500 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ | |
1501 | ||
1502 | /* If there are errors need to be reported for unknown parameters, | |
1503 | * make sure to reserve enough room in the INIT ACK for them. | |
1504 | */ | |
1505 | len = 0; | |
1506 | if (err_chunk) { | |
1507 | len = ntohs(err_chunk->chunk_hdr->length) - | |
1508 | sizeof(sctp_chunkhdr_t); | |
1509 | } | |
1510 | ||
1da177e4 LT |
1511 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); |
1512 | if (!repl) | |
1513 | goto nomem; | |
1514 | ||
1515 | /* If there are errors need to be reported for unknown parameters, | |
1516 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
1517 | * parameter. | |
1518 | */ | |
1519 | if (err_chunk) { | |
1520 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
1521 | * ERROR chunk generated by sctp_verify_init(). Since the | |
1522 | * error cause code for "unknown parameter" and the | |
1523 | * "Unrecognized parameter" type is the same, we can | |
1524 | * construct the parameters in INIT ACK by copying the | |
1525 | * ERROR causes over. | |
1526 | */ | |
1527 | unk_param = (sctp_unrecognized_param_t *) | |
1528 | ((__u8 *)(err_chunk->chunk_hdr) + | |
1529 | sizeof(sctp_chunkhdr_t)); | |
1530 | /* Replace the cause code with the "Unrecognized parameter" | |
1531 | * parameter type. | |
1532 | */ | |
1533 | sctp_addto_chunk(repl, len, unk_param); | |
1534 | } | |
1535 | ||
1536 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
1537 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1538 | ||
1539 | /* | |
1540 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
1541 | * "Z" MUST NOT allocate any resources for this new association. | |
1542 | * Otherwise, "Z" will be vulnerable to resource attacks. | |
1543 | */ | |
1544 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
1545 | retval = SCTP_DISPOSITION_CONSUME; | |
1546 | ||
df7deeb5 VY |
1547 | return retval; |
1548 | ||
1549 | nomem: | |
1550 | retval = SCTP_DISPOSITION_NOMEM; | |
1551 | nomem_retval: | |
1552 | if (new_asoc) | |
1553 | sctp_association_free(new_asoc); | |
1da177e4 LT |
1554 | cleanup: |
1555 | if (err_chunk) | |
1556 | sctp_chunk_free(err_chunk); | |
1557 | return retval; | |
1da177e4 LT |
1558 | } |
1559 | ||
1560 | /* | |
25985edc | 1561 | * Handle simultaneous INIT. |
1da177e4 LT |
1562 | * This means we started an INIT and then we got an INIT request from |
1563 | * our peer. | |
1564 | * | |
1565 | * Section: 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State (Item B) | |
1566 | * This usually indicates an initialization collision, i.e., each | |
1567 | * endpoint is attempting, at about the same time, to establish an | |
1568 | * association with the other endpoint. | |
1569 | * | |
1570 | * Upon receipt of an INIT in the COOKIE-WAIT or COOKIE-ECHOED state, an | |
1571 | * endpoint MUST respond with an INIT ACK using the same parameters it | |
1572 | * sent in its original INIT chunk (including its Verification Tag, | |
1573 | * unchanged). These original parameters are combined with those from the | |
1574 | * newly received INIT chunk. The endpoint shall also generate a State | |
1575 | * Cookie with the INIT ACK. The endpoint uses the parameters sent in its | |
1576 | * INIT to calculate the State Cookie. | |
1577 | * | |
1578 | * After that, the endpoint MUST NOT change its state, the T1-init | |
1579 | * timer shall be left running and the corresponding TCB MUST NOT be | |
1580 | * destroyed. The normal procedures for handling State Cookies when | |
1581 | * a TCB exists will resolve the duplicate INITs to a single association. | |
1582 | * | |
1583 | * For an endpoint that is in the COOKIE-ECHOED state it MUST populate | |
1584 | * its Tie-Tags with the Tag information of itself and its peer (see | |
1585 | * section 5.2.2 for a description of the Tie-Tags). | |
1586 | * | |
1587 | * Verification Tag: Not explicit, but an INIT can not have a valid | |
1588 | * verification tag, so we skip the check. | |
1589 | * | |
1590 | * Inputs | |
1591 | * (endpoint, asoc, chunk) | |
1592 | * | |
1593 | * Outputs | |
1594 | * (asoc, reply_msg, msg_up, timers, counters) | |
1595 | * | |
1596 | * The return value is the disposition of the chunk. | |
1597 | */ | |
24cb81a6 EB |
1598 | sctp_disposition_t sctp_sf_do_5_2_1_siminit(struct net *net, |
1599 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
1600 | const struct sctp_association *asoc, |
1601 | const sctp_subtype_t type, | |
1602 | void *arg, | |
1603 | sctp_cmd_seq_t *commands) | |
1604 | { | |
1605 | /* Call helper to do the real work for both simulataneous and | |
1606 | * duplicate INIT chunk handling. | |
1607 | */ | |
24cb81a6 | 1608 | return sctp_sf_do_unexpected_init(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1609 | } |
1610 | ||
1611 | /* | |
1612 | * Handle duplicated INIT messages. These are usually delayed | |
1613 | * restransmissions. | |
1614 | * | |
1615 | * Section: 5.2.2 Unexpected INIT in States Other than CLOSED, | |
1616 | * COOKIE-ECHOED and COOKIE-WAIT | |
1617 | * | |
1618 | * Unless otherwise stated, upon reception of an unexpected INIT for | |
1619 | * this association, the endpoint shall generate an INIT ACK with a | |
1620 | * State Cookie. In the outbound INIT ACK the endpoint MUST copy its | |
1621 | * current Verification Tag and peer's Verification Tag into a reserved | |
1622 | * place within the state cookie. We shall refer to these locations as | |
1623 | * the Peer's-Tie-Tag and the Local-Tie-Tag. The outbound SCTP packet | |
1624 | * containing this INIT ACK MUST carry a Verification Tag value equal to | |
1625 | * the Initiation Tag found in the unexpected INIT. And the INIT ACK | |
1626 | * MUST contain a new Initiation Tag (randomly generated see Section | |
1627 | * 5.3.1). Other parameters for the endpoint SHOULD be copied from the | |
1628 | * existing parameters of the association (e.g. number of outbound | |
1629 | * streams) into the INIT ACK and cookie. | |
1630 | * | |
1631 | * After sending out the INIT ACK, the endpoint shall take no further | |
1632 | * actions, i.e., the existing association, including its current state, | |
1633 | * and the corresponding TCB MUST NOT be changed. | |
1634 | * | |
1635 | * Note: Only when a TCB exists and the association is not in a COOKIE- | |
1636 | * WAIT state are the Tie-Tags populated. For a normal association INIT | |
1637 | * (i.e. the endpoint is in a COOKIE-WAIT state), the Tie-Tags MUST be | |
1638 | * set to 0 (indicating that no previous TCB existed). The INIT ACK and | |
1639 | * State Cookie are populated as specified in section 5.2.1. | |
1640 | * | |
1641 | * Verification Tag: Not specified, but an INIT has no way of knowing | |
1642 | * what the verification tag could be, so we ignore it. | |
1643 | * | |
1644 | * Inputs | |
1645 | * (endpoint, asoc, chunk) | |
1646 | * | |
1647 | * Outputs | |
1648 | * (asoc, reply_msg, msg_up, timers, counters) | |
1649 | * | |
1650 | * The return value is the disposition of the chunk. | |
1651 | */ | |
24cb81a6 EB |
1652 | sctp_disposition_t sctp_sf_do_5_2_2_dupinit(struct net *net, |
1653 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
1654 | const struct sctp_association *asoc, |
1655 | const sctp_subtype_t type, | |
1656 | void *arg, | |
1657 | sctp_cmd_seq_t *commands) | |
1658 | { | |
1659 | /* Call helper to do the real work for both simulataneous and | |
1660 | * duplicate INIT chunk handling. | |
1661 | */ | |
24cb81a6 | 1662 | return sctp_sf_do_unexpected_init(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1663 | } |
1664 | ||
1665 | ||
610ab73a VY |
1666 | /* |
1667 | * Unexpected INIT-ACK handler. | |
1668 | * | |
1669 | * Section 5.2.3 | |
1670 | * If an INIT ACK received by an endpoint in any state other than the | |
1671 | * COOKIE-WAIT state, the endpoint should discard the INIT ACK chunk. | |
1672 | * An unexpected INIT ACK usually indicates the processing of an old or | |
1673 | * duplicated INIT chunk. | |
1674 | */ | |
24cb81a6 EB |
1675 | sctp_disposition_t sctp_sf_do_5_2_3_initack(struct net *net, |
1676 | const struct sctp_endpoint *ep, | |
610ab73a VY |
1677 | const struct sctp_association *asoc, |
1678 | const sctp_subtype_t type, | |
1679 | void *arg, sctp_cmd_seq_t *commands) | |
1680 | { | |
1681 | /* Per the above section, we'll discard the chunk if we have an | |
1682 | * endpoint. If this is an OOTB INIT-ACK, treat it as such. | |
1683 | */ | |
2ce95503 | 1684 | if (ep == sctp_sk(net->sctp.ctl_sock)->ep) |
24cb81a6 | 1685 | return sctp_sf_ootb(net, ep, asoc, type, arg, commands); |
610ab73a | 1686 | else |
24cb81a6 | 1687 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
610ab73a | 1688 | } |
1da177e4 LT |
1689 | |
1690 | /* Unexpected COOKIE-ECHO handler for peer restart (Table 2, action 'A') | |
1691 | * | |
1692 | * Section 5.2.4 | |
1693 | * A) In this case, the peer may have restarted. | |
1694 | */ | |
24cb81a6 EB |
1695 | static sctp_disposition_t sctp_sf_do_dupcook_a(struct net *net, |
1696 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
1697 | const struct sctp_association *asoc, |
1698 | struct sctp_chunk *chunk, | |
1699 | sctp_cmd_seq_t *commands, | |
1700 | struct sctp_association *new_asoc) | |
1701 | { | |
1702 | sctp_init_chunk_t *peer_init; | |
1703 | struct sctp_ulpevent *ev; | |
1704 | struct sctp_chunk *repl; | |
1705 | struct sctp_chunk *err; | |
1706 | sctp_disposition_t disposition; | |
1707 | ||
1708 | /* new_asoc is a brand-new association, so these are not yet | |
1709 | * side effects--it is safe to run them here. | |
1710 | */ | |
1711 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
1712 | ||
de6becdc | 1713 | if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), peer_init, |
1da177e4 LT |
1714 | GFP_ATOMIC)) |
1715 | goto nomem; | |
1716 | ||
1717 | /* Make sure no new addresses are being added during the | |
1718 | * restart. Though this is a pretty complicated attack | |
1719 | * since you'd have to get inside the cookie. | |
1720 | */ | |
1721 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, commands)) { | |
1722 | return SCTP_DISPOSITION_CONSUME; | |
1723 | } | |
1724 | ||
1725 | /* If the endpoint is in the SHUTDOWN-ACK-SENT state and recognizes | |
1726 | * the peer has restarted (Action A), it MUST NOT setup a new | |
1727 | * association but instead resend the SHUTDOWN ACK and send an ERROR | |
1728 | * chunk with a "Cookie Received while Shutting Down" error cause to | |
1729 | * its peer. | |
1730 | */ | |
1731 | if (sctp_state(asoc, SHUTDOWN_ACK_SENT)) { | |
24cb81a6 | 1732 | disposition = sctp_sf_do_9_2_reshutack(net, ep, asoc, |
1da177e4 LT |
1733 | SCTP_ST_CHUNK(chunk->chunk_hdr->type), |
1734 | chunk, commands); | |
1735 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
1736 | goto nomem; | |
1737 | ||
1738 | err = sctp_make_op_error(asoc, chunk, | |
1739 | SCTP_ERROR_COOKIE_IN_SHUTDOWN, | |
6383cfb3 | 1740 | NULL, 0, 0); |
1da177e4 LT |
1741 | if (err) |
1742 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
1743 | SCTP_CHUNK(err)); | |
1744 | ||
1745 | return SCTP_DISPOSITION_CONSUME; | |
1746 | } | |
1747 | ||
a000c01e WY |
1748 | /* For now, stop pending T3-rtx and SACK timers, fail any unsent/unacked |
1749 | * data. Consider the optional choice of resending of this data. | |
1da177e4 | 1750 | */ |
a000c01e WY |
1751 | sctp_add_cmd_sf(commands, SCTP_CMD_T3_RTX_TIMERS_STOP, SCTP_NULL()); |
1752 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
1753 | SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); | |
1da177e4 LT |
1754 | sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_OUTQUEUE, SCTP_NULL()); |
1755 | ||
a000c01e WY |
1756 | /* Stop pending T4-rto timer, teardown ASCONF queue, ASCONF-ACK queue |
1757 | * and ASCONF-ACK cache. | |
1758 | */ | |
1759 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
1760 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
1761 | sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_ASCONF_QUEUE, SCTP_NULL()); | |
1762 | ||
1da177e4 LT |
1763 | repl = sctp_make_cookie_ack(new_asoc, chunk); |
1764 | if (!repl) | |
1765 | goto nomem; | |
1766 | ||
1da177e4 LT |
1767 | /* Report association restart to upper layer. */ |
1768 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_RESTART, 0, | |
1769 | new_asoc->c.sinit_num_ostreams, | |
1770 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 1771 | NULL, GFP_ATOMIC); |
1da177e4 LT |
1772 | if (!ev) |
1773 | goto nomem_ev; | |
1774 | ||
df7deeb5 VY |
1775 | /* Update the content of current association. */ |
1776 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1da177e4 | 1777 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
bdf6fa52 VY |
1778 | if (sctp_state(asoc, SHUTDOWN_PENDING) && |
1779 | (sctp_sstate(asoc->base.sk, CLOSING) || | |
1780 | sock_flag(asoc->base.sk, SOCK_DEAD))) { | |
1781 | /* if were currently in SHUTDOWN_PENDING, but the socket | |
1782 | * has been closed by user, don't transition to ESTABLISHED. | |
1783 | * Instead trigger SHUTDOWN bundled with COOKIE_ACK. | |
1784 | */ | |
1785 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1786 | return sctp_sf_do_9_2_start_shutdown(net, ep, asoc, | |
1787 | SCTP_ST_CHUNK(0), NULL, | |
1788 | commands); | |
1789 | } else { | |
1790 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1791 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
1792 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1793 | } | |
1da177e4 LT |
1794 | return SCTP_DISPOSITION_CONSUME; |
1795 | ||
1796 | nomem_ev: | |
1797 | sctp_chunk_free(repl); | |
1798 | nomem: | |
1799 | return SCTP_DISPOSITION_NOMEM; | |
1800 | } | |
1801 | ||
1802 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'B') | |
1803 | * | |
1804 | * Section 5.2.4 | |
1805 | * B) In this case, both sides may be attempting to start an association | |
1806 | * at about the same time but the peer endpoint started its INIT | |
1807 | * after responding to the local endpoint's INIT | |
1808 | */ | |
1809 | /* This case represents an initialization collision. */ | |
24cb81a6 EB |
1810 | static sctp_disposition_t sctp_sf_do_dupcook_b(struct net *net, |
1811 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
1812 | const struct sctp_association *asoc, |
1813 | struct sctp_chunk *chunk, | |
1814 | sctp_cmd_seq_t *commands, | |
1815 | struct sctp_association *new_asoc) | |
1816 | { | |
1817 | sctp_init_chunk_t *peer_init; | |
1da177e4 LT |
1818 | struct sctp_chunk *repl; |
1819 | ||
1820 | /* new_asoc is a brand-new association, so these are not yet | |
1821 | * side effects--it is safe to run them here. | |
1822 | */ | |
1823 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
de6becdc | 1824 | if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), peer_init, |
1da177e4 LT |
1825 | GFP_ATOMIC)) |
1826 | goto nomem; | |
1827 | ||
1828 | /* Update the content of current association. */ | |
1829 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1830 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1831 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
24cb81a6 | 1832 | SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB); |
1da177e4 LT |
1833 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); |
1834 | ||
1835 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
1836 | if (!repl) | |
1837 | goto nomem; | |
1838 | ||
1839 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1da177e4 LT |
1840 | |
1841 | /* RFC 2960 5.1 Normal Establishment of an Association | |
1842 | * | |
1843 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
1844 | * send the Communication Up notification to the SCTP user | |
1845 | * upon reception of a valid COOKIE ECHO chunk. | |
07d93967 VY |
1846 | * |
1847 | * Sadly, this needs to be implemented as a side-effect, because | |
1848 | * we are not guaranteed to have set the association id of the real | |
1849 | * association and so these notifications need to be delayed until | |
1850 | * the association id is allocated. | |
1da177e4 | 1851 | */ |
1da177e4 | 1852 | |
07d93967 | 1853 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_CHANGE, SCTP_U8(SCTP_COMM_UP)); |
1da177e4 LT |
1854 | |
1855 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 1856 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 1857 | * delivers this notification to inform the application that of the |
0f3fffd8 | 1858 | * peers requested adaptation layer. |
07d93967 VY |
1859 | * |
1860 | * This also needs to be done as a side effect for the same reason as | |
1861 | * above. | |
1da177e4 | 1862 | */ |
07d93967 VY |
1863 | if (asoc->peer.adaptation_ind) |
1864 | sctp_add_cmd_sf(commands, SCTP_CMD_ADAPTATION_IND, SCTP_NULL()); | |
1da177e4 LT |
1865 | |
1866 | return SCTP_DISPOSITION_CONSUME; | |
1867 | ||
1da177e4 LT |
1868 | nomem: |
1869 | return SCTP_DISPOSITION_NOMEM; | |
1870 | } | |
1871 | ||
1872 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'C') | |
1873 | * | |
1874 | * Section 5.2.4 | |
1875 | * C) In this case, the local endpoint's cookie has arrived late. | |
1876 | * Before it arrived, the local endpoint sent an INIT and received an | |
1877 | * INIT-ACK and finally sent a COOKIE ECHO with the peer's same tag | |
1878 | * but a new tag of its own. | |
1879 | */ | |
1880 | /* This case represents an initialization collision. */ | |
24cb81a6 EB |
1881 | static sctp_disposition_t sctp_sf_do_dupcook_c(struct net *net, |
1882 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
1883 | const struct sctp_association *asoc, |
1884 | struct sctp_chunk *chunk, | |
1885 | sctp_cmd_seq_t *commands, | |
1886 | struct sctp_association *new_asoc) | |
1887 | { | |
1888 | /* The cookie should be silently discarded. | |
1889 | * The endpoint SHOULD NOT change states and should leave | |
1890 | * any timers running. | |
1891 | */ | |
1892 | return SCTP_DISPOSITION_DISCARD; | |
1893 | } | |
1894 | ||
1895 | /* Unexpected COOKIE-ECHO handler lost chunk (Table 2, action 'D') | |
1896 | * | |
1897 | * Section 5.2.4 | |
1898 | * | |
1899 | * D) When both local and remote tags match the endpoint should always | |
1900 | * enter the ESTABLISHED state, if it has not already done so. | |
1901 | */ | |
1902 | /* This case represents an initialization collision. */ | |
24cb81a6 EB |
1903 | static sctp_disposition_t sctp_sf_do_dupcook_d(struct net *net, |
1904 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
1905 | const struct sctp_association *asoc, |
1906 | struct sctp_chunk *chunk, | |
1907 | sctp_cmd_seq_t *commands, | |
1908 | struct sctp_association *new_asoc) | |
1909 | { | |
df7deeb5 | 1910 | struct sctp_ulpevent *ev = NULL, *ai_ev = NULL; |
1da177e4 LT |
1911 | struct sctp_chunk *repl; |
1912 | ||
1913 | /* Clarification from Implementor's Guide: | |
1914 | * D) When both local and remote tags match the endpoint should | |
d808ad9a YH |
1915 | * enter the ESTABLISHED state, if it is in the COOKIE-ECHOED state. |
1916 | * It should stop any cookie timer that may be running and send | |
1917 | * a COOKIE ACK. | |
1da177e4 LT |
1918 | */ |
1919 | ||
1920 | /* Don't accidentally move back into established state. */ | |
1921 | if (asoc->state < SCTP_STATE_ESTABLISHED) { | |
1922 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
1923 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
1924 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1925 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
24cb81a6 | 1926 | SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB); |
1da177e4 LT |
1927 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, |
1928 | SCTP_NULL()); | |
1929 | ||
1930 | /* RFC 2960 5.1 Normal Establishment of an Association | |
1931 | * | |
1932 | * D) IMPLEMENTATION NOTE: An implementation may choose | |
1933 | * to send the Communication Up notification to the | |
1934 | * SCTP user upon reception of a valid COOKIE | |
1935 | * ECHO chunk. | |
1936 | */ | |
df7deeb5 | 1937 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, |
1da177e4 | 1938 | SCTP_COMM_UP, 0, |
df7deeb5 VY |
1939 | asoc->c.sinit_num_ostreams, |
1940 | asoc->c.sinit_max_instreams, | |
9cbcbf4e | 1941 | NULL, GFP_ATOMIC); |
1da177e4 LT |
1942 | if (!ev) |
1943 | goto nomem; | |
1da177e4 LT |
1944 | |
1945 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 1946 | * When a peer sends a Adaptation Layer Indication parameter, |
1da177e4 | 1947 | * SCTP delivers this notification to inform the application |
0f3fffd8 | 1948 | * that of the peers requested adaptation layer. |
1da177e4 | 1949 | */ |
0f3fffd8 ISJ |
1950 | if (asoc->peer.adaptation_ind) { |
1951 | ai_ev = sctp_ulpevent_make_adaptation_indication(asoc, | |
1da177e4 | 1952 | GFP_ATOMIC); |
df7deeb5 | 1953 | if (!ai_ev) |
1da177e4 LT |
1954 | goto nomem; |
1955 | ||
1da177e4 LT |
1956 | } |
1957 | } | |
1da177e4 LT |
1958 | |
1959 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
1960 | if (!repl) | |
1961 | goto nomem; | |
1962 | ||
2e3216cd VY |
1963 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
1964 | ||
df7deeb5 VY |
1965 | if (ev) |
1966 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
1967 | SCTP_ULPEVENT(ev)); | |
1968 | if (ai_ev) | |
1969 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
1970 | SCTP_ULPEVENT(ai_ev)); | |
1971 | ||
1da177e4 LT |
1972 | return SCTP_DISPOSITION_CONSUME; |
1973 | ||
1974 | nomem: | |
df7deeb5 VY |
1975 | if (ai_ev) |
1976 | sctp_ulpevent_free(ai_ev); | |
1da177e4 LT |
1977 | if (ev) |
1978 | sctp_ulpevent_free(ev); | |
1979 | return SCTP_DISPOSITION_NOMEM; | |
1980 | } | |
1981 | ||
1982 | /* | |
1983 | * Handle a duplicate COOKIE-ECHO. This usually means a cookie-carrying | |
1984 | * chunk was retransmitted and then delayed in the network. | |
1985 | * | |
1986 | * Section: 5.2.4 Handle a COOKIE ECHO when a TCB exists | |
1987 | * | |
1988 | * Verification Tag: None. Do cookie validation. | |
1989 | * | |
1990 | * Inputs | |
1991 | * (endpoint, asoc, chunk) | |
1992 | * | |
1993 | * Outputs | |
1994 | * (asoc, reply_msg, msg_up, timers, counters) | |
1995 | * | |
1996 | * The return value is the disposition of the chunk. | |
1997 | */ | |
24cb81a6 EB |
1998 | sctp_disposition_t sctp_sf_do_5_2_4_dupcook(struct net *net, |
1999 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2000 | const struct sctp_association *asoc, |
2001 | const sctp_subtype_t type, | |
2002 | void *arg, | |
2003 | sctp_cmd_seq_t *commands) | |
2004 | { | |
2005 | sctp_disposition_t retval; | |
2006 | struct sctp_chunk *chunk = arg; | |
2007 | struct sctp_association *new_asoc; | |
2008 | int error = 0; | |
2009 | char action; | |
2010 | struct sctp_chunk *err_chk_p; | |
2011 | ||
2012 | /* Make sure that the chunk has a valid length from the protocol | |
2013 | * perspective. In this case check to make sure we have at least | |
2014 | * enough for the chunk header. Cookie length verification is | |
2015 | * done later. | |
2016 | */ | |
2017 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 2018 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
2019 | commands); |
2020 | ||
2021 | /* "Decode" the chunk. We have no optional parameters so we | |
2022 | * are in good shape. | |
2023 | */ | |
d808ad9a | 2024 | chunk->subh.cookie_hdr = (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 SS |
2025 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
2026 | sizeof(sctp_chunkhdr_t))) | |
2027 | goto nomem; | |
1da177e4 LT |
2028 | |
2029 | /* In RFC 2960 5.2.4 3, if both Verification Tags in the State Cookie | |
2030 | * of a duplicate COOKIE ECHO match the Verification Tags of the | |
2031 | * current association, consider the State Cookie valid even if | |
2032 | * the lifespan is exceeded. | |
2033 | */ | |
2034 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
2035 | &err_chk_p); | |
2036 | ||
2037 | /* FIXME: | |
2038 | * If the re-build failed, what is the proper error path | |
2039 | * from here? | |
2040 | * | |
2041 | * [We should abort the association. --piggy] | |
2042 | */ | |
2043 | if (!new_asoc) { | |
2044 | /* FIXME: Several errors are possible. A bad cookie should | |
2045 | * be silently discarded, but think about logging it too. | |
2046 | */ | |
2047 | switch (error) { | |
2048 | case -SCTP_IERROR_NOMEM: | |
2049 | goto nomem; | |
2050 | ||
2051 | case -SCTP_IERROR_STALE_COOKIE: | |
24cb81a6 | 2052 | sctp_send_stale_cookie_err(net, ep, asoc, chunk, commands, |
1da177e4 | 2053 | err_chk_p); |
24cb81a6 | 2054 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2055 | case -SCTP_IERROR_BAD_SIG: |
2056 | default: | |
24cb81a6 | 2057 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
3ff50b79 | 2058 | } |
1da177e4 LT |
2059 | } |
2060 | ||
2061 | /* Compare the tie_tag in cookie with the verification tag of | |
2062 | * current association. | |
2063 | */ | |
2064 | action = sctp_tietags_compare(new_asoc, asoc); | |
2065 | ||
2066 | switch (action) { | |
2067 | case 'A': /* Association restart. */ | |
24cb81a6 | 2068 | retval = sctp_sf_do_dupcook_a(net, ep, asoc, chunk, commands, |
1da177e4 LT |
2069 | new_asoc); |
2070 | break; | |
2071 | ||
2072 | case 'B': /* Collision case B. */ | |
24cb81a6 | 2073 | retval = sctp_sf_do_dupcook_b(net, ep, asoc, chunk, commands, |
1da177e4 LT |
2074 | new_asoc); |
2075 | break; | |
2076 | ||
2077 | case 'C': /* Collision case C. */ | |
24cb81a6 | 2078 | retval = sctp_sf_do_dupcook_c(net, ep, asoc, chunk, commands, |
1da177e4 LT |
2079 | new_asoc); |
2080 | break; | |
2081 | ||
2082 | case 'D': /* Collision case D. */ | |
24cb81a6 | 2083 | retval = sctp_sf_do_dupcook_d(net, ep, asoc, chunk, commands, |
1da177e4 LT |
2084 | new_asoc); |
2085 | break; | |
2086 | ||
2087 | default: /* Discard packet for all others. */ | |
24cb81a6 | 2088 | retval = sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 2089 | break; |
3ff50b79 | 2090 | } |
1da177e4 LT |
2091 | |
2092 | /* Delete the tempory new association. */ | |
f2815633 | 2093 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_ASOC, SCTP_ASOC(new_asoc)); |
1da177e4 LT |
2094 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); |
2095 | ||
d5ccd496 MM |
2096 | /* Restore association pointer to provide SCTP command interpeter |
2097 | * with a valid context in case it needs to manipulate | |
2098 | * the queues */ | |
2099 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_ASOC, | |
2100 | SCTP_ASOC((struct sctp_association *)asoc)); | |
2101 | ||
1da177e4 LT |
2102 | return retval; |
2103 | ||
2104 | nomem: | |
2105 | return SCTP_DISPOSITION_NOMEM; | |
2106 | } | |
2107 | ||
2108 | /* | |
2109 | * Process an ABORT. (SHUTDOWN-PENDING state) | |
2110 | * | |
2111 | * See sctp_sf_do_9_1_abort(). | |
2112 | */ | |
2113 | sctp_disposition_t sctp_sf_shutdown_pending_abort( | |
24cb81a6 | 2114 | struct net *net, |
1da177e4 LT |
2115 | const struct sctp_endpoint *ep, |
2116 | const struct sctp_association *asoc, | |
2117 | const sctp_subtype_t type, | |
2118 | void *arg, | |
2119 | sctp_cmd_seq_t *commands) | |
2120 | { | |
2121 | struct sctp_chunk *chunk = arg; | |
2122 | ||
2123 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
24cb81a6 | 2124 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2125 | |
2126 | /* Make sure that the ABORT chunk has a valid length. | |
2127 | * Since this is an ABORT chunk, we have to discard it | |
2128 | * because of the following text: | |
2129 | * RFC 2960, Section 3.3.7 | |
2130 | * If an endpoint receives an ABORT with a format error or for an | |
2131 | * association that doesn't exist, it MUST silently discard it. | |
25985edc | 2132 | * Because the length is "invalid", we can't really discard just |
1da177e4 LT |
2133 | * as we do not know its true length. So, to be safe, discard the |
2134 | * packet. | |
2135 | */ | |
2136 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
24cb81a6 | 2137 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 2138 | |
75205f47 VY |
2139 | /* ADD-IP: Special case for ABORT chunks |
2140 | * F4) One special consideration is that ABORT Chunks arriving | |
2141 | * destined to the IP address being deleted MUST be | |
2142 | * ignored (see Section 5.3.1 for further details). | |
2143 | */ | |
2144 | if (SCTP_ADDR_DEL == | |
2145 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
24cb81a6 | 2146 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
75205f47 | 2147 | |
24cb81a6 | 2148 | return __sctp_sf_do_9_1_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2149 | } |
2150 | ||
2151 | /* | |
2152 | * Process an ABORT. (SHUTDOWN-SENT state) | |
2153 | * | |
2154 | * See sctp_sf_do_9_1_abort(). | |
2155 | */ | |
24cb81a6 EB |
2156 | sctp_disposition_t sctp_sf_shutdown_sent_abort(struct net *net, |
2157 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2158 | const struct sctp_association *asoc, |
2159 | const sctp_subtype_t type, | |
2160 | void *arg, | |
2161 | sctp_cmd_seq_t *commands) | |
2162 | { | |
2163 | struct sctp_chunk *chunk = arg; | |
2164 | ||
2165 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
24cb81a6 | 2166 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2167 | |
2168 | /* Make sure that the ABORT chunk has a valid length. | |
2169 | * Since this is an ABORT chunk, we have to discard it | |
2170 | * because of the following text: | |
2171 | * RFC 2960, Section 3.3.7 | |
2172 | * If an endpoint receives an ABORT with a format error or for an | |
2173 | * association that doesn't exist, it MUST silently discard it. | |
25985edc | 2174 | * Because the length is "invalid", we can't really discard just |
1da177e4 LT |
2175 | * as we do not know its true length. So, to be safe, discard the |
2176 | * packet. | |
2177 | */ | |
2178 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
24cb81a6 | 2179 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 2180 | |
75205f47 VY |
2181 | /* ADD-IP: Special case for ABORT chunks |
2182 | * F4) One special consideration is that ABORT Chunks arriving | |
2183 | * destined to the IP address being deleted MUST be | |
2184 | * ignored (see Section 5.3.1 for further details). | |
2185 | */ | |
2186 | if (SCTP_ADDR_DEL == | |
2187 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
24cb81a6 | 2188 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
75205f47 | 2189 | |
1da177e4 LT |
2190 | /* Stop the T2-shutdown timer. */ |
2191 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2192 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2193 | ||
2194 | /* Stop the T5-shutdown guard timer. */ | |
2195 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2196 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
2197 | ||
24cb81a6 | 2198 | return __sctp_sf_do_9_1_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2199 | } |
2200 | ||
2201 | /* | |
2202 | * Process an ABORT. (SHUTDOWN-ACK-SENT state) | |
2203 | * | |
2204 | * See sctp_sf_do_9_1_abort(). | |
2205 | */ | |
2206 | sctp_disposition_t sctp_sf_shutdown_ack_sent_abort( | |
24cb81a6 | 2207 | struct net *net, |
1da177e4 LT |
2208 | const struct sctp_endpoint *ep, |
2209 | const struct sctp_association *asoc, | |
2210 | const sctp_subtype_t type, | |
2211 | void *arg, | |
2212 | sctp_cmd_seq_t *commands) | |
2213 | { | |
2214 | /* The same T2 timer, so we should be able to use | |
2215 | * common function with the SHUTDOWN-SENT state. | |
2216 | */ | |
24cb81a6 | 2217 | return sctp_sf_shutdown_sent_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2218 | } |
2219 | ||
2220 | /* | |
2221 | * Handle an Error received in COOKIE_ECHOED state. | |
2222 | * | |
2223 | * Only handle the error type of stale COOKIE Error, the other errors will | |
2224 | * be ignored. | |
2225 | * | |
2226 | * Inputs | |
2227 | * (endpoint, asoc, chunk) | |
2228 | * | |
2229 | * Outputs | |
2230 | * (asoc, reply_msg, msg_up, timers, counters) | |
2231 | * | |
2232 | * The return value is the disposition of the chunk. | |
2233 | */ | |
24cb81a6 EB |
2234 | sctp_disposition_t sctp_sf_cookie_echoed_err(struct net *net, |
2235 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2236 | const struct sctp_association *asoc, |
2237 | const sctp_subtype_t type, | |
2238 | void *arg, | |
2239 | sctp_cmd_seq_t *commands) | |
2240 | { | |
2241 | struct sctp_chunk *chunk = arg; | |
2242 | sctp_errhdr_t *err; | |
2243 | ||
2244 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 2245 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2246 | |
2247 | /* Make sure that the ERROR chunk has a valid length. | |
2248 | * The parameter walking depends on this as well. | |
2249 | */ | |
2250 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t))) | |
24cb81a6 | 2251 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
2252 | commands); |
2253 | ||
2254 | /* Process the error here */ | |
2255 | /* FUTURE FIXME: When PR-SCTP related and other optional | |
2256 | * parms are emitted, this will have to change to handle multiple | |
2257 | * errors. | |
2258 | */ | |
2259 | sctp_walk_errors(err, chunk->chunk_hdr) { | |
2260 | if (SCTP_ERROR_STALE_COOKIE == err->cause) | |
24cb81a6 | 2261 | return sctp_sf_do_5_2_6_stale(net, ep, asoc, type, |
1da177e4 LT |
2262 | arg, commands); |
2263 | } | |
2264 | ||
2265 | /* It is possible to have malformed error causes, and that | |
2266 | * will cause us to end the walk early. However, since | |
2267 | * we are discarding the packet, there should be no adverse | |
2268 | * affects. | |
2269 | */ | |
24cb81a6 | 2270 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2271 | } |
2272 | ||
2273 | /* | |
2274 | * Handle a Stale COOKIE Error | |
2275 | * | |
2276 | * Section: 5.2.6 Handle Stale COOKIE Error | |
2277 | * If the association is in the COOKIE-ECHOED state, the endpoint may elect | |
2278 | * one of the following three alternatives. | |
2279 | * ... | |
2280 | * 3) Send a new INIT chunk to the endpoint, adding a Cookie | |
2281 | * Preservative parameter requesting an extension to the lifetime of | |
2282 | * the State Cookie. When calculating the time extension, an | |
2283 | * implementation SHOULD use the RTT information measured based on the | |
2284 | * previous COOKIE ECHO / ERROR exchange, and should add no more | |
2285 | * than 1 second beyond the measured RTT, due to long State Cookie | |
2286 | * lifetimes making the endpoint more subject to a replay attack. | |
2287 | * | |
2288 | * Verification Tag: Not explicit, but safe to ignore. | |
2289 | * | |
2290 | * Inputs | |
2291 | * (endpoint, asoc, chunk) | |
2292 | * | |
2293 | * Outputs | |
2294 | * (asoc, reply_msg, msg_up, timers, counters) | |
2295 | * | |
2296 | * The return value is the disposition of the chunk. | |
2297 | */ | |
24cb81a6 EB |
2298 | static sctp_disposition_t sctp_sf_do_5_2_6_stale(struct net *net, |
2299 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2300 | const struct sctp_association *asoc, |
2301 | const sctp_subtype_t type, | |
2302 | void *arg, | |
2303 | sctp_cmd_seq_t *commands) | |
2304 | { | |
2305 | struct sctp_chunk *chunk = arg; | |
2306 | time_t stale; | |
2307 | sctp_cookie_preserve_param_t bht; | |
2308 | sctp_errhdr_t *err; | |
2309 | struct sctp_chunk *reply; | |
2310 | struct sctp_bind_addr *bp; | |
3f7a87d2 | 2311 | int attempts = asoc->init_err_counter + 1; |
1da177e4 | 2312 | |
81845c21 | 2313 | if (attempts > asoc->max_init_attempts) { |
8de8c873 SS |
2314 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
2315 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 2316 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 2317 | SCTP_PERR(SCTP_ERROR_STALE_COOKIE)); |
1da177e4 LT |
2318 | return SCTP_DISPOSITION_DELETE_TCB; |
2319 | } | |
2320 | ||
2321 | err = (sctp_errhdr_t *)(chunk->skb->data); | |
2322 | ||
2323 | /* When calculating the time extension, an implementation | |
2324 | * SHOULD use the RTT information measured based on the | |
2325 | * previous COOKIE ECHO / ERROR exchange, and should add no | |
2326 | * more than 1 second beyond the measured RTT, due to long | |
2327 | * State Cookie lifetimes making the endpoint more subject to | |
2328 | * a replay attack. | |
2329 | * Measure of Staleness's unit is usec. (1/1000000 sec) | |
2330 | * Suggested Cookie Life-span Increment's unit is msec. | |
2331 | * (1/1000 sec) | |
2332 | * In general, if you use the suggested cookie life, the value | |
2333 | * found in the field of measure of staleness should be doubled | |
2334 | * to give ample time to retransmit the new cookie and thus | |
2335 | * yield a higher probability of success on the reattempt. | |
2336 | */ | |
34bcca28 | 2337 | stale = ntohl(*(__be32 *)((u8 *)err + sizeof(sctp_errhdr_t))); |
1da177e4 LT |
2338 | stale = (stale * 2) / 1000; |
2339 | ||
2340 | bht.param_hdr.type = SCTP_PARAM_COOKIE_PRESERVATIVE; | |
2341 | bht.param_hdr.length = htons(sizeof(bht)); | |
2342 | bht.lifespan_increment = htonl(stale); | |
2343 | ||
2344 | /* Build that new INIT chunk. */ | |
2345 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; | |
2346 | reply = sctp_make_init(asoc, bp, GFP_ATOMIC, sizeof(bht)); | |
2347 | if (!reply) | |
2348 | goto nomem; | |
2349 | ||
2350 | sctp_addto_chunk(reply, sizeof(bht), &bht); | |
2351 | ||
2352 | /* Clear peer's init_tag cached in assoc as we are sending a new INIT */ | |
2353 | sctp_add_cmd_sf(commands, SCTP_CMD_CLEAR_INIT_TAG, SCTP_NULL()); | |
2354 | ||
2355 | /* Stop pending T3-rtx and heartbeat timers */ | |
2356 | sctp_add_cmd_sf(commands, SCTP_CMD_T3_RTX_TIMERS_STOP, SCTP_NULL()); | |
2357 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
2358 | ||
2359 | /* Delete non-primary peer ip addresses since we are transitioning | |
2360 | * back to the COOKIE-WAIT state | |
2361 | */ | |
2362 | sctp_add_cmd_sf(commands, SCTP_CMD_DEL_NON_PRIMARY, SCTP_NULL()); | |
2363 | ||
d808ad9a YH |
2364 | /* If we've sent any data bundled with COOKIE-ECHO we will need to |
2365 | * resend | |
1da177e4 | 2366 | */ |
b6157d8e | 2367 | sctp_add_cmd_sf(commands, SCTP_CMD_T1_RETRAN, |
1da177e4 LT |
2368 | SCTP_TRANSPORT(asoc->peer.primary_path)); |
2369 | ||
2370 | /* Cast away the const modifier, as we want to just | |
2371 | * rerun it through as a sideffect. | |
2372 | */ | |
3f7a87d2 | 2373 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_INC, SCTP_NULL()); |
1da177e4 LT |
2374 | |
2375 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2376 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
2377 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2378 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
2379 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
2380 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
2381 | ||
2382 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2383 | ||
2384 | return SCTP_DISPOSITION_CONSUME; | |
2385 | ||
2386 | nomem: | |
2387 | return SCTP_DISPOSITION_NOMEM; | |
2388 | } | |
2389 | ||
2390 | /* | |
2391 | * Process an ABORT. | |
2392 | * | |
2393 | * Section: 9.1 | |
2394 | * After checking the Verification Tag, the receiving endpoint shall | |
2395 | * remove the association from its record, and shall report the | |
2396 | * termination to its upper layer. | |
2397 | * | |
2398 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
2399 | * B) Rules for packet carrying ABORT: | |
2400 | * | |
2401 | * - The endpoint shall always fill in the Verification Tag field of the | |
2402 | * outbound packet with the destination endpoint's tag value if it | |
2403 | * is known. | |
2404 | * | |
2405 | * - If the ABORT is sent in response to an OOTB packet, the endpoint | |
2406 | * MUST follow the procedure described in Section 8.4. | |
2407 | * | |
2408 | * - The receiver MUST accept the packet if the Verification Tag | |
2409 | * matches either its own tag, OR the tag of its peer. Otherwise, the | |
2410 | * receiver MUST silently discard the packet and take no further | |
2411 | * action. | |
2412 | * | |
2413 | * Inputs | |
2414 | * (endpoint, asoc, chunk) | |
2415 | * | |
2416 | * Outputs | |
2417 | * (asoc, reply_msg, msg_up, timers, counters) | |
2418 | * | |
2419 | * The return value is the disposition of the chunk. | |
2420 | */ | |
24cb81a6 EB |
2421 | sctp_disposition_t sctp_sf_do_9_1_abort(struct net *net, |
2422 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2423 | const struct sctp_association *asoc, |
2424 | const sctp_subtype_t type, | |
2425 | void *arg, | |
2426 | sctp_cmd_seq_t *commands) | |
2427 | { | |
2428 | struct sctp_chunk *chunk = arg; | |
1da177e4 LT |
2429 | |
2430 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
24cb81a6 | 2431 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2432 | |
2433 | /* Make sure that the ABORT chunk has a valid length. | |
2434 | * Since this is an ABORT chunk, we have to discard it | |
2435 | * because of the following text: | |
2436 | * RFC 2960, Section 3.3.7 | |
2437 | * If an endpoint receives an ABORT with a format error or for an | |
2438 | * association that doesn't exist, it MUST silently discard it. | |
25985edc | 2439 | * Because the length is "invalid", we can't really discard just |
1da177e4 LT |
2440 | * as we do not know its true length. So, to be safe, discard the |
2441 | * packet. | |
2442 | */ | |
2443 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
24cb81a6 | 2444 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 2445 | |
75205f47 VY |
2446 | /* ADD-IP: Special case for ABORT chunks |
2447 | * F4) One special consideration is that ABORT Chunks arriving | |
2448 | * destined to the IP address being deleted MUST be | |
2449 | * ignored (see Section 5.3.1 for further details). | |
2450 | */ | |
2451 | if (SCTP_ADDR_DEL == | |
2452 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
24cb81a6 | 2453 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
75205f47 | 2454 | |
24cb81a6 | 2455 | return __sctp_sf_do_9_1_abort(net, ep, asoc, type, arg, commands); |
75205f47 VY |
2456 | } |
2457 | ||
24cb81a6 EB |
2458 | static sctp_disposition_t __sctp_sf_do_9_1_abort(struct net *net, |
2459 | const struct sctp_endpoint *ep, | |
75205f47 VY |
2460 | const struct sctp_association *asoc, |
2461 | const sctp_subtype_t type, | |
2462 | void *arg, | |
2463 | sctp_cmd_seq_t *commands) | |
2464 | { | |
2465 | struct sctp_chunk *chunk = arg; | |
95c96174 | 2466 | unsigned int len; |
75205f47 VY |
2467 | __be16 error = SCTP_ERROR_NO_ERROR; |
2468 | ||
1da177e4 LT |
2469 | /* See if we have an error cause code in the chunk. */ |
2470 | len = ntohs(chunk->chunk_hdr->length); | |
96ca468b SW |
2471 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) { |
2472 | ||
2473 | sctp_errhdr_t *err; | |
2474 | sctp_walk_errors(err, chunk->chunk_hdr); | |
2475 | if ((void *)err != (void *)chunk->chunk_end) | |
24cb81a6 | 2476 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
96ca468b | 2477 | |
1da177e4 | 2478 | error = ((sctp_errhdr_t *)chunk->skb->data)->cause; |
96ca468b | 2479 | } |
1da177e4 | 2480 | |
8de8c873 | 2481 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNRESET)); |
d808ad9a | 2482 | /* ASSOC_FAILED will DELETE_TCB. */ |
5be291fe | 2483 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_PERR(error)); |
b01a2407 EB |
2484 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
2485 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
2486 | |
2487 | return SCTP_DISPOSITION_ABORT; | |
2488 | } | |
2489 | ||
2490 | /* | |
2491 | * Process an ABORT. (COOKIE-WAIT state) | |
2492 | * | |
2493 | * See sctp_sf_do_9_1_abort() above. | |
2494 | */ | |
24cb81a6 EB |
2495 | sctp_disposition_t sctp_sf_cookie_wait_abort(struct net *net, |
2496 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2497 | const struct sctp_association *asoc, |
2498 | const sctp_subtype_t type, | |
2499 | void *arg, | |
2500 | sctp_cmd_seq_t *commands) | |
2501 | { | |
2502 | struct sctp_chunk *chunk = arg; | |
95c96174 | 2503 | unsigned int len; |
f94c0198 | 2504 | __be16 error = SCTP_ERROR_NO_ERROR; |
1da177e4 LT |
2505 | |
2506 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
24cb81a6 | 2507 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2508 | |
2509 | /* Make sure that the ABORT chunk has a valid length. | |
2510 | * Since this is an ABORT chunk, we have to discard it | |
2511 | * because of the following text: | |
2512 | * RFC 2960, Section 3.3.7 | |
2513 | * If an endpoint receives an ABORT with a format error or for an | |
2514 | * association that doesn't exist, it MUST silently discard it. | |
25985edc | 2515 | * Because the length is "invalid", we can't really discard just |
1da177e4 LT |
2516 | * as we do not know its true length. So, to be safe, discard the |
2517 | * packet. | |
2518 | */ | |
2519 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
24cb81a6 | 2520 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2521 | |
2522 | /* See if we have an error cause code in the chunk. */ | |
2523 | len = ntohs(chunk->chunk_hdr->length); | |
2524 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) | |
2525 | error = ((sctp_errhdr_t *)chunk->skb->data)->cause; | |
2526 | ||
24cb81a6 | 2527 | return sctp_stop_t1_and_abort(net, commands, error, ECONNREFUSED, asoc, |
8de8c873 | 2528 | chunk->transport); |
1da177e4 LT |
2529 | } |
2530 | ||
2531 | /* | |
2532 | * Process an incoming ICMP as an ABORT. (COOKIE-WAIT state) | |
2533 | */ | |
24cb81a6 EB |
2534 | sctp_disposition_t sctp_sf_cookie_wait_icmp_abort(struct net *net, |
2535 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2536 | const struct sctp_association *asoc, |
2537 | const sctp_subtype_t type, | |
2538 | void *arg, | |
2539 | sctp_cmd_seq_t *commands) | |
2540 | { | |
24cb81a6 | 2541 | return sctp_stop_t1_and_abort(net, commands, SCTP_ERROR_NO_ERROR, |
8de8c873 | 2542 | ENOPROTOOPT, asoc, |
3f7a87d2 | 2543 | (struct sctp_transport *)arg); |
1da177e4 LT |
2544 | } |
2545 | ||
2546 | /* | |
2547 | * Process an ABORT. (COOKIE-ECHOED state) | |
2548 | */ | |
24cb81a6 EB |
2549 | sctp_disposition_t sctp_sf_cookie_echoed_abort(struct net *net, |
2550 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2551 | const struct sctp_association *asoc, |
2552 | const sctp_subtype_t type, | |
2553 | void *arg, | |
2554 | sctp_cmd_seq_t *commands) | |
2555 | { | |
2556 | /* There is a single T1 timer, so we should be able to use | |
2557 | * common function with the COOKIE-WAIT state. | |
2558 | */ | |
24cb81a6 | 2559 | return sctp_sf_cookie_wait_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2560 | } |
2561 | ||
2562 | /* | |
2563 | * Stop T1 timer and abort association with "INIT failed". | |
2564 | * | |
2565 | * This is common code called by several sctp_sf_*_abort() functions above. | |
2566 | */ | |
24cb81a6 EB |
2567 | static sctp_disposition_t sctp_stop_t1_and_abort(struct net *net, |
2568 | sctp_cmd_seq_t *commands, | |
f94c0198 | 2569 | __be16 error, int sk_err, |
3f7a87d2 FF |
2570 | const struct sctp_association *asoc, |
2571 | struct sctp_transport *transport) | |
1da177e4 | 2572 | { |
bb33381d DB |
2573 | pr_debug("%s: ABORT received (INIT)\n", __func__); |
2574 | ||
1da177e4 LT |
2575 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
2576 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
24cb81a6 | 2577 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
1da177e4 LT |
2578 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, |
2579 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
8de8c873 | 2580 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(sk_err)); |
1da177e4 LT |
2581 | /* CMD_INIT_FAILED will DELETE_TCB. */ |
2582 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 2583 | SCTP_PERR(error)); |
bb33381d | 2584 | |
3f7a87d2 | 2585 | return SCTP_DISPOSITION_ABORT; |
1da177e4 LT |
2586 | } |
2587 | ||
2588 | /* | |
2589 | * sctp_sf_do_9_2_shut | |
2590 | * | |
2591 | * Section: 9.2 | |
2592 | * Upon the reception of the SHUTDOWN, the peer endpoint shall | |
2593 | * - enter the SHUTDOWN-RECEIVED state, | |
2594 | * | |
2595 | * - stop accepting new data from its SCTP user | |
2596 | * | |
2597 | * - verify, by checking the Cumulative TSN Ack field of the chunk, | |
2598 | * that all its outstanding DATA chunks have been received by the | |
2599 | * SHUTDOWN sender. | |
2600 | * | |
2601 | * Once an endpoint as reached the SHUTDOWN-RECEIVED state it MUST NOT | |
2602 | * send a SHUTDOWN in response to a ULP request. And should discard | |
2603 | * subsequent SHUTDOWN chunks. | |
2604 | * | |
2605 | * If there are still outstanding DATA chunks left, the SHUTDOWN | |
2606 | * receiver shall continue to follow normal data transmission | |
2607 | * procedures defined in Section 6 until all outstanding DATA chunks | |
2608 | * are acknowledged; however, the SHUTDOWN receiver MUST NOT accept | |
2609 | * new data from its SCTP user. | |
2610 | * | |
2611 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2612 | * | |
2613 | * Inputs | |
2614 | * (endpoint, asoc, chunk) | |
2615 | * | |
2616 | * Outputs | |
2617 | * (asoc, reply_msg, msg_up, timers, counters) | |
2618 | * | |
2619 | * The return value is the disposition of the chunk. | |
2620 | */ | |
24cb81a6 EB |
2621 | sctp_disposition_t sctp_sf_do_9_2_shutdown(struct net *net, |
2622 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2623 | const struct sctp_association *asoc, |
2624 | const sctp_subtype_t type, | |
2625 | void *arg, | |
2626 | sctp_cmd_seq_t *commands) | |
2627 | { | |
2628 | struct sctp_chunk *chunk = arg; | |
2629 | sctp_shutdownhdr_t *sdh; | |
2630 | sctp_disposition_t disposition; | |
2631 | struct sctp_ulpevent *ev; | |
df10eec4 | 2632 | __u32 ctsn; |
1da177e4 LT |
2633 | |
2634 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 2635 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2636 | |
2637 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
2638 | if (!sctp_chunk_length_valid(chunk, | |
2639 | sizeof(struct sctp_shutdown_chunk_t))) | |
24cb81a6 | 2640 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
2641 | commands); |
2642 | ||
2643 | /* Convert the elaborate header. */ | |
2644 | sdh = (sctp_shutdownhdr_t *)chunk->skb->data; | |
2645 | skb_pull(chunk->skb, sizeof(sctp_shutdownhdr_t)); | |
2646 | chunk->subh.shutdown_hdr = sdh; | |
df10eec4 WY |
2647 | ctsn = ntohl(sdh->cum_tsn_ack); |
2648 | ||
a2f36eec | 2649 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { |
bb33381d DB |
2650 | pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn, |
2651 | asoc->ctsn_ack_point); | |
2652 | ||
a2f36eec WY |
2653 | return SCTP_DISPOSITION_DISCARD; |
2654 | } | |
2655 | ||
df10eec4 WY |
2656 | /* If Cumulative TSN Ack beyond the max tsn currently |
2657 | * send, terminating the association and respond to the | |
2658 | * sender with an ABORT. | |
2659 | */ | |
2660 | if (!TSN_lt(ctsn, asoc->next_tsn)) | |
24cb81a6 | 2661 | return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands); |
1da177e4 | 2662 | |
eb0e0076 SS |
2663 | /* API 5.3.1.5 SCTP_SHUTDOWN_EVENT |
2664 | * When a peer sends a SHUTDOWN, SCTP delivers this notification to | |
2665 | * inform the application that it should cease sending data. | |
2666 | */ | |
2667 | ev = sctp_ulpevent_make_shutdown_event(asoc, 0, GFP_ATOMIC); | |
2668 | if (!ev) { | |
2669 | disposition = SCTP_DISPOSITION_NOMEM; | |
d808ad9a | 2670 | goto out; |
eb0e0076 SS |
2671 | } |
2672 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
2673 | ||
1da177e4 LT |
2674 | /* Upon the reception of the SHUTDOWN, the peer endpoint shall |
2675 | * - enter the SHUTDOWN-RECEIVED state, | |
2676 | * - stop accepting new data from its SCTP user | |
2677 | * | |
2678 | * [This is implicit in the new state.] | |
2679 | */ | |
2680 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2681 | SCTP_STATE(SCTP_STATE_SHUTDOWN_RECEIVED)); | |
2682 | disposition = SCTP_DISPOSITION_CONSUME; | |
2683 | ||
2684 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
24cb81a6 | 2685 | disposition = sctp_sf_do_9_2_shutdown_ack(net, ep, asoc, type, |
1da177e4 LT |
2686 | arg, commands); |
2687 | } | |
2688 | ||
2689 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
2690 | goto out; | |
2691 | ||
2692 | /* - verify, by checking the Cumulative TSN Ack field of the | |
2693 | * chunk, that all its outstanding DATA chunks have been | |
2694 | * received by the SHUTDOWN sender. | |
2695 | */ | |
2696 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN, | |
2178eda8 | 2697 | SCTP_BE32(chunk->subh.shutdown_hdr->cum_tsn_ack)); |
1da177e4 | 2698 | |
1da177e4 LT |
2699 | out: |
2700 | return disposition; | |
2701 | } | |
2702 | ||
2e3f92da WY |
2703 | /* |
2704 | * sctp_sf_do_9_2_shut_ctsn | |
2705 | * | |
2706 | * Once an endpoint has reached the SHUTDOWN-RECEIVED state, | |
2707 | * it MUST NOT send a SHUTDOWN in response to a ULP request. | |
2708 | * The Cumulative TSN Ack of the received SHUTDOWN chunk | |
2709 | * MUST be processed. | |
2710 | */ | |
24cb81a6 EB |
2711 | sctp_disposition_t sctp_sf_do_9_2_shut_ctsn(struct net *net, |
2712 | const struct sctp_endpoint *ep, | |
2e3f92da WY |
2713 | const struct sctp_association *asoc, |
2714 | const sctp_subtype_t type, | |
2715 | void *arg, | |
2716 | sctp_cmd_seq_t *commands) | |
2717 | { | |
2718 | struct sctp_chunk *chunk = arg; | |
2719 | sctp_shutdownhdr_t *sdh; | |
a2f36eec | 2720 | __u32 ctsn; |
2e3f92da WY |
2721 | |
2722 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 2723 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
2e3f92da WY |
2724 | |
2725 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
2726 | if (!sctp_chunk_length_valid(chunk, | |
2727 | sizeof(struct sctp_shutdown_chunk_t))) | |
24cb81a6 | 2728 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
2e3f92da WY |
2729 | commands); |
2730 | ||
2731 | sdh = (sctp_shutdownhdr_t *)chunk->skb->data; | |
a2f36eec WY |
2732 | ctsn = ntohl(sdh->cum_tsn_ack); |
2733 | ||
2734 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { | |
bb33381d DB |
2735 | pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn, |
2736 | asoc->ctsn_ack_point); | |
2737 | ||
a2f36eec WY |
2738 | return SCTP_DISPOSITION_DISCARD; |
2739 | } | |
2e3f92da WY |
2740 | |
2741 | /* If Cumulative TSN Ack beyond the max tsn currently | |
2742 | * send, terminating the association and respond to the | |
2743 | * sender with an ABORT. | |
2744 | */ | |
a2f36eec | 2745 | if (!TSN_lt(ctsn, asoc->next_tsn)) |
24cb81a6 | 2746 | return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands); |
2e3f92da WY |
2747 | |
2748 | /* verify, by checking the Cumulative TSN Ack field of the | |
2749 | * chunk, that all its outstanding DATA chunks have been | |
2750 | * received by the SHUTDOWN sender. | |
2751 | */ | |
2752 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN, | |
2753 | SCTP_BE32(sdh->cum_tsn_ack)); | |
2754 | ||
2755 | return SCTP_DISPOSITION_CONSUME; | |
2756 | } | |
2757 | ||
1da177e4 LT |
2758 | /* RFC 2960 9.2 |
2759 | * If an endpoint is in SHUTDOWN-ACK-SENT state and receives an INIT chunk | |
2760 | * (e.g., if the SHUTDOWN COMPLETE was lost) with source and destination | |
2761 | * transport addresses (either in the IP addresses or in the INIT chunk) | |
2762 | * that belong to this association, it should discard the INIT chunk and | |
2763 | * retransmit the SHUTDOWN ACK chunk. | |
2764 | */ | |
24cb81a6 EB |
2765 | sctp_disposition_t sctp_sf_do_9_2_reshutack(struct net *net, |
2766 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2767 | const struct sctp_association *asoc, |
2768 | const sctp_subtype_t type, | |
2769 | void *arg, | |
2770 | sctp_cmd_seq_t *commands) | |
2771 | { | |
2772 | struct sctp_chunk *chunk = (struct sctp_chunk *) arg; | |
2773 | struct sctp_chunk *reply; | |
2774 | ||
ece25dfa VY |
2775 | /* Make sure that the chunk has a valid length */ |
2776 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 2777 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa VY |
2778 | commands); |
2779 | ||
1da177e4 LT |
2780 | /* Since we are not going to really process this INIT, there |
2781 | * is no point in verifying chunk boundries. Just generate | |
2782 | * the SHUTDOWN ACK. | |
2783 | */ | |
2784 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
2785 | if (NULL == reply) | |
2786 | goto nomem; | |
2787 | ||
2788 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
2789 | * the T2-SHUTDOWN timer. | |
2790 | */ | |
2791 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
2792 | ||
2793 | /* and restart the T2-shutdown timer. */ | |
2794 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2795 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2796 | ||
2797 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2798 | ||
2799 | return SCTP_DISPOSITION_CONSUME; | |
2800 | nomem: | |
2801 | return SCTP_DISPOSITION_NOMEM; | |
2802 | } | |
2803 | ||
2804 | /* | |
2805 | * sctp_sf_do_ecn_cwr | |
2806 | * | |
2807 | * Section: Appendix A: Explicit Congestion Notification | |
2808 | * | |
2809 | * CWR: | |
2810 | * | |
2811 | * RFC 2481 details a specific bit for a sender to send in the header of | |
2812 | * its next outbound TCP segment to indicate to its peer that it has | |
2813 | * reduced its congestion window. This is termed the CWR bit. For | |
2814 | * SCTP the same indication is made by including the CWR chunk. | |
2815 | * This chunk contains one data element, i.e. the TSN number that | |
2816 | * was sent in the ECNE chunk. This element represents the lowest | |
2817 | * TSN number in the datagram that was originally marked with the | |
2818 | * CE bit. | |
2819 | * | |
2820 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2821 | * Inputs | |
2822 | * (endpoint, asoc, chunk) | |
2823 | * | |
2824 | * Outputs | |
2825 | * (asoc, reply_msg, msg_up, timers, counters) | |
2826 | * | |
2827 | * The return value is the disposition of the chunk. | |
2828 | */ | |
24cb81a6 EB |
2829 | sctp_disposition_t sctp_sf_do_ecn_cwr(struct net *net, |
2830 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2831 | const struct sctp_association *asoc, |
2832 | const sctp_subtype_t type, | |
2833 | void *arg, | |
2834 | sctp_cmd_seq_t *commands) | |
2835 | { | |
2836 | sctp_cwrhdr_t *cwr; | |
2837 | struct sctp_chunk *chunk = arg; | |
34bcca28 | 2838 | u32 lowest_tsn; |
1da177e4 LT |
2839 | |
2840 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 2841 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2842 | |
2843 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t))) | |
24cb81a6 | 2844 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 | 2845 | commands); |
d808ad9a | 2846 | |
1da177e4 LT |
2847 | cwr = (sctp_cwrhdr_t *) chunk->skb->data; |
2848 | skb_pull(chunk->skb, sizeof(sctp_cwrhdr_t)); | |
2849 | ||
34bcca28 | 2850 | lowest_tsn = ntohl(cwr->lowest_tsn); |
1da177e4 LT |
2851 | |
2852 | /* Does this CWR ack the last sent congestion notification? */ | |
34bcca28 | 2853 | if (TSN_lte(asoc->last_ecne_tsn, lowest_tsn)) { |
1da177e4 LT |
2854 | /* Stop sending ECNE. */ |
2855 | sctp_add_cmd_sf(commands, | |
2856 | SCTP_CMD_ECN_CWR, | |
34bcca28 | 2857 | SCTP_U32(lowest_tsn)); |
1da177e4 LT |
2858 | } |
2859 | return SCTP_DISPOSITION_CONSUME; | |
2860 | } | |
2861 | ||
2862 | /* | |
2863 | * sctp_sf_do_ecne | |
2864 | * | |
2865 | * Section: Appendix A: Explicit Congestion Notification | |
2866 | * | |
2867 | * ECN-Echo | |
2868 | * | |
2869 | * RFC 2481 details a specific bit for a receiver to send back in its | |
2870 | * TCP acknowledgements to notify the sender of the Congestion | |
2871 | * Experienced (CE) bit having arrived from the network. For SCTP this | |
2872 | * same indication is made by including the ECNE chunk. This chunk | |
2873 | * contains one data element, i.e. the lowest TSN associated with the IP | |
2874 | * datagram marked with the CE bit..... | |
2875 | * | |
2876 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2877 | * Inputs | |
2878 | * (endpoint, asoc, chunk) | |
2879 | * | |
2880 | * Outputs | |
2881 | * (asoc, reply_msg, msg_up, timers, counters) | |
2882 | * | |
2883 | * The return value is the disposition of the chunk. | |
2884 | */ | |
24cb81a6 EB |
2885 | sctp_disposition_t sctp_sf_do_ecne(struct net *net, |
2886 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2887 | const struct sctp_association *asoc, |
2888 | const sctp_subtype_t type, | |
2889 | void *arg, | |
2890 | sctp_cmd_seq_t *commands) | |
2891 | { | |
2892 | sctp_ecnehdr_t *ecne; | |
2893 | struct sctp_chunk *chunk = arg; | |
2894 | ||
2895 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 2896 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2897 | |
2898 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t))) | |
24cb81a6 | 2899 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
2900 | commands); |
2901 | ||
2902 | ecne = (sctp_ecnehdr_t *) chunk->skb->data; | |
2903 | skb_pull(chunk->skb, sizeof(sctp_ecnehdr_t)); | |
2904 | ||
2905 | /* If this is a newer ECNE than the last CWR packet we sent out */ | |
2906 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_ECNE, | |
2907 | SCTP_U32(ntohl(ecne->lowest_tsn))); | |
2908 | ||
2909 | return SCTP_DISPOSITION_CONSUME; | |
2910 | } | |
2911 | ||
2912 | /* | |
2913 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
2914 | * | |
2915 | * The SCTP endpoint MUST always acknowledge the reception of each valid | |
2916 | * DATA chunk. | |
2917 | * | |
2918 | * The guidelines on delayed acknowledgement algorithm specified in | |
2919 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
2920 | * acknowledgement SHOULD be generated for at least every second packet | |
2921 | * (not every second DATA chunk) received, and SHOULD be generated within | |
2922 | * 200 ms of the arrival of any unacknowledged DATA chunk. In some | |
2923 | * situations it may be beneficial for an SCTP transmitter to be more | |
2924 | * conservative than the algorithms detailed in this document allow. | |
2925 | * However, an SCTP transmitter MUST NOT be more aggressive than the | |
2926 | * following algorithms allow. | |
2927 | * | |
2928 | * A SCTP receiver MUST NOT generate more than one SACK for every | |
2929 | * incoming packet, other than to update the offered window as the | |
2930 | * receiving application consumes new data. | |
2931 | * | |
2932 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2933 | * | |
2934 | * Inputs | |
2935 | * (endpoint, asoc, chunk) | |
2936 | * | |
2937 | * Outputs | |
2938 | * (asoc, reply_msg, msg_up, timers, counters) | |
2939 | * | |
2940 | * The return value is the disposition of the chunk. | |
2941 | */ | |
24cb81a6 EB |
2942 | sctp_disposition_t sctp_sf_eat_data_6_2(struct net *net, |
2943 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
2944 | const struct sctp_association *asoc, |
2945 | const sctp_subtype_t type, | |
2946 | void *arg, | |
2947 | sctp_cmd_seq_t *commands) | |
2948 | { | |
2949 | struct sctp_chunk *chunk = arg; | |
6dc7694f | 2950 | sctp_arg_t force = SCTP_NOFORCE(); |
1da177e4 LT |
2951 | int error; |
2952 | ||
2953 | if (!sctp_vtag_verify(chunk, asoc)) { | |
2954 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
2955 | SCTP_NULL()); | |
24cb81a6 | 2956 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
d808ad9a | 2957 | } |
1da177e4 LT |
2958 | |
2959 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t))) | |
24cb81a6 | 2960 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
2961 | commands); |
2962 | ||
cb3f837b | 2963 | error = sctp_eat_data(asoc, chunk, commands); |
1da177e4 LT |
2964 | switch (error) { |
2965 | case SCTP_IERROR_NO_ERROR: | |
2966 | break; | |
2967 | case SCTP_IERROR_HIGH_TSN: | |
2968 | case SCTP_IERROR_BAD_STREAM: | |
24cb81a6 | 2969 | SCTP_INC_STATS(net, SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
2970 | goto discard_noforce; |
2971 | case SCTP_IERROR_DUP_TSN: | |
2972 | case SCTP_IERROR_IGNORE_TSN: | |
24cb81a6 | 2973 | SCTP_INC_STATS(net, SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
2974 | goto discard_force; |
2975 | case SCTP_IERROR_NO_DATA: | |
2976 | goto consume; | |
f1751c57 | 2977 | case SCTP_IERROR_PROTO_VIOLATION: |
24cb81a6 | 2978 | return sctp_sf_abort_violation(net, ep, asoc, chunk, commands, |
f1751c57 | 2979 | (u8 *)chunk->subh.data_hdr, sizeof(sctp_datahdr_t)); |
1da177e4 LT |
2980 | default: |
2981 | BUG(); | |
2982 | } | |
2983 | ||
6dc7694f WY |
2984 | if (chunk->chunk_hdr->flags & SCTP_DATA_SACK_IMM) |
2985 | force = SCTP_FORCE(); | |
2986 | ||
9f70f46b | 2987 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) { |
1da177e4 LT |
2988 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, |
2989 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
2990 | } | |
2991 | ||
2992 | /* If this is the last chunk in a packet, we need to count it | |
2993 | * toward sack generation. Note that we need to SACK every | |
2994 | * OTHER packet containing data chunks, EVEN IF WE DISCARD | |
2995 | * THEM. We elect to NOT generate SACK's if the chunk fails | |
2996 | * the verification tag test. | |
2997 | * | |
2998 | * RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
2999 | * | |
3000 | * The SCTP endpoint MUST always acknowledge the reception of | |
3001 | * each valid DATA chunk. | |
3002 | * | |
3003 | * The guidelines on delayed acknowledgement algorithm | |
3004 | * specified in Section 4.2 of [RFC2581] SHOULD be followed. | |
3005 | * Specifically, an acknowledgement SHOULD be generated for at | |
3006 | * least every second packet (not every second DATA chunk) | |
3007 | * received, and SHOULD be generated within 200 ms of the | |
3008 | * arrival of any unacknowledged DATA chunk. In some | |
3009 | * situations it may be beneficial for an SCTP transmitter to | |
3010 | * be more conservative than the algorithms detailed in this | |
3011 | * document allow. However, an SCTP transmitter MUST NOT be | |
3012 | * more aggressive than the following algorithms allow. | |
3013 | */ | |
52ccb8e9 | 3014 | if (chunk->end_of_packet) |
6dc7694f | 3015 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, force); |
1da177e4 | 3016 | |
1da177e4 LT |
3017 | return SCTP_DISPOSITION_CONSUME; |
3018 | ||
3019 | discard_force: | |
3020 | /* RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
3021 | * | |
3022 | * When a packet arrives with duplicate DATA chunk(s) and with | |
3023 | * no new DATA chunk(s), the endpoint MUST immediately send a | |
3024 | * SACK with no delay. If a packet arrives with duplicate | |
3025 | * DATA chunk(s) bundled with new DATA chunks, the endpoint | |
3026 | * MAY immediately send a SACK. Normally receipt of duplicate | |
3027 | * DATA chunks will occur when the original SACK chunk was lost | |
3028 | * and the peer's RTO has expired. The duplicate TSN number(s) | |
3029 | * SHOULD be reported in the SACK as duplicate. | |
3030 | */ | |
3031 | /* In our case, we split the MAY SACK advice up whether or not | |
3032 | * the last chunk is a duplicate.' | |
3033 | */ | |
3034 | if (chunk->end_of_packet) | |
3035 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
3036 | return SCTP_DISPOSITION_DISCARD; | |
3037 | ||
3038 | discard_noforce: | |
52ccb8e9 | 3039 | if (chunk->end_of_packet) |
6dc7694f | 3040 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, force); |
1da177e4 | 3041 | |
1da177e4 LT |
3042 | return SCTP_DISPOSITION_DISCARD; |
3043 | consume: | |
3044 | return SCTP_DISPOSITION_CONSUME; | |
d808ad9a | 3045 | |
1da177e4 LT |
3046 | } |
3047 | ||
3048 | /* | |
3049 | * sctp_sf_eat_data_fast_4_4 | |
3050 | * | |
3051 | * Section: 4 (4) | |
3052 | * (4) In SHUTDOWN-SENT state the endpoint MUST acknowledge any received | |
3053 | * DATA chunks without delay. | |
3054 | * | |
3055 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3056 | * Inputs | |
3057 | * (endpoint, asoc, chunk) | |
3058 | * | |
3059 | * Outputs | |
3060 | * (asoc, reply_msg, msg_up, timers, counters) | |
3061 | * | |
3062 | * The return value is the disposition of the chunk. | |
3063 | */ | |
24cb81a6 EB |
3064 | sctp_disposition_t sctp_sf_eat_data_fast_4_4(struct net *net, |
3065 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3066 | const struct sctp_association *asoc, |
3067 | const sctp_subtype_t type, | |
3068 | void *arg, | |
3069 | sctp_cmd_seq_t *commands) | |
3070 | { | |
3071 | struct sctp_chunk *chunk = arg; | |
3072 | int error; | |
3073 | ||
3074 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3075 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3076 | SCTP_NULL()); | |
24cb81a6 | 3077 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3078 | } |
3079 | ||
3080 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t))) | |
24cb81a6 | 3081 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3082 | commands); |
3083 | ||
cb3f837b | 3084 | error = sctp_eat_data(asoc, chunk, commands); |
1da177e4 LT |
3085 | switch (error) { |
3086 | case SCTP_IERROR_NO_ERROR: | |
3087 | case SCTP_IERROR_HIGH_TSN: | |
3088 | case SCTP_IERROR_DUP_TSN: | |
3089 | case SCTP_IERROR_IGNORE_TSN: | |
3090 | case SCTP_IERROR_BAD_STREAM: | |
3091 | break; | |
3092 | case SCTP_IERROR_NO_DATA: | |
3093 | goto consume; | |
f1751c57 | 3094 | case SCTP_IERROR_PROTO_VIOLATION: |
24cb81a6 | 3095 | return sctp_sf_abort_violation(net, ep, asoc, chunk, commands, |
f1751c57 | 3096 | (u8 *)chunk->subh.data_hdr, sizeof(sctp_datahdr_t)); |
1da177e4 LT |
3097 | default: |
3098 | BUG(); | |
3099 | } | |
3100 | ||
3101 | /* Go a head and force a SACK, since we are shutting down. */ | |
3102 | ||
3103 | /* Implementor's Guide. | |
3104 | * | |
3105 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
3106 | * respond to each received packet containing one or more DATA chunk(s) | |
3107 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
3108 | */ | |
3109 | if (chunk->end_of_packet) { | |
3110 | /* We must delay the chunk creation since the cumulative | |
3111 | * TSN has not been updated yet. | |
3112 | */ | |
3113 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
3114 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
3115 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3116 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3117 | } | |
3118 | ||
3119 | consume: | |
3120 | return SCTP_DISPOSITION_CONSUME; | |
3121 | } | |
3122 | ||
3123 | /* | |
3124 | * Section: 6.2 Processing a Received SACK | |
3125 | * D) Any time a SACK arrives, the endpoint performs the following: | |
3126 | * | |
3127 | * i) If Cumulative TSN Ack is less than the Cumulative TSN Ack Point, | |
3128 | * then drop the SACK. Since Cumulative TSN Ack is monotonically | |
3129 | * increasing, a SACK whose Cumulative TSN Ack is less than the | |
3130 | * Cumulative TSN Ack Point indicates an out-of-order SACK. | |
3131 | * | |
3132 | * ii) Set rwnd equal to the newly received a_rwnd minus the number | |
3133 | * of bytes still outstanding after processing the Cumulative TSN Ack | |
3134 | * and the Gap Ack Blocks. | |
3135 | * | |
3136 | * iii) If the SACK is missing a TSN that was previously | |
3137 | * acknowledged via a Gap Ack Block (e.g., the data receiver | |
3138 | * reneged on the data), then mark the corresponding DATA chunk | |
3139 | * as available for retransmit: Mark it as missing for fast | |
3140 | * retransmit as described in Section 7.2.4 and if no retransmit | |
3141 | * timer is running for the destination address to which the DATA | |
3142 | * chunk was originally transmitted, then T3-rtx is started for | |
3143 | * that destination address. | |
3144 | * | |
3145 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3146 | * | |
3147 | * Inputs | |
3148 | * (endpoint, asoc, chunk) | |
3149 | * | |
3150 | * Outputs | |
3151 | * (asoc, reply_msg, msg_up, timers, counters) | |
3152 | * | |
3153 | * The return value is the disposition of the chunk. | |
3154 | */ | |
24cb81a6 EB |
3155 | sctp_disposition_t sctp_sf_eat_sack_6_2(struct net *net, |
3156 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3157 | const struct sctp_association *asoc, |
3158 | const sctp_subtype_t type, | |
3159 | void *arg, | |
3160 | sctp_cmd_seq_t *commands) | |
3161 | { | |
3162 | struct sctp_chunk *chunk = arg; | |
3163 | sctp_sackhdr_t *sackh; | |
3164 | __u32 ctsn; | |
3165 | ||
3166 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 3167 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3168 | |
3169 | /* Make sure that the SACK chunk has a valid length. */ | |
3170 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_sack_chunk_t))) | |
24cb81a6 | 3171 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3172 | commands); |
3173 | ||
3174 | /* Pull the SACK chunk from the data buffer */ | |
3175 | sackh = sctp_sm_pull_sack(chunk); | |
3176 | /* Was this a bogus SACK? */ | |
3177 | if (!sackh) | |
24cb81a6 | 3178 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3179 | chunk->subh.sack_hdr = sackh; |
3180 | ctsn = ntohl(sackh->cum_tsn_ack); | |
3181 | ||
3182 | /* i) If Cumulative TSN Ack is less than the Cumulative TSN | |
3183 | * Ack Point, then drop the SACK. Since Cumulative TSN | |
3184 | * Ack is monotonically increasing, a SACK whose | |
3185 | * Cumulative TSN Ack is less than the Cumulative TSN Ack | |
3186 | * Point indicates an out-of-order SACK. | |
3187 | */ | |
3188 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { | |
bb33381d DB |
3189 | pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn, |
3190 | asoc->ctsn_ack_point); | |
3191 | ||
1da177e4 LT |
3192 | return SCTP_DISPOSITION_DISCARD; |
3193 | } | |
3194 | ||
aecedeab WY |
3195 | /* If Cumulative TSN Ack beyond the max tsn currently |
3196 | * send, terminating the association and respond to the | |
3197 | * sender with an ABORT. | |
3198 | */ | |
3199 | if (!TSN_lt(ctsn, asoc->next_tsn)) | |
24cb81a6 | 3200 | return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands); |
aecedeab | 3201 | |
1da177e4 | 3202 | /* Return this SACK for further processing. */ |
edfee033 | 3203 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, SCTP_CHUNK(chunk)); |
1da177e4 LT |
3204 | |
3205 | /* Note: We do the rest of the work on the PROCESS_SACK | |
3206 | * sideeffect. | |
3207 | */ | |
3208 | return SCTP_DISPOSITION_CONSUME; | |
3209 | } | |
3210 | ||
3211 | /* | |
3212 | * Generate an ABORT in response to a packet. | |
3213 | * | |
047a2428 | 3214 | * Section: 8.4 Handle "Out of the blue" Packets, sctpimpguide 2.41 |
1da177e4 | 3215 | * |
047a2428 JF |
3216 | * 8) The receiver should respond to the sender of the OOTB packet with |
3217 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
3218 | * MUST fill in the Verification Tag field of the outbound packet | |
3219 | * with the value found in the Verification Tag field of the OOTB | |
3220 | * packet and set the T-bit in the Chunk Flags to indicate that the | |
3221 | * Verification Tag is reflected. After sending this ABORT, the | |
3222 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
3223 | * no further action. | |
1da177e4 LT |
3224 | * |
3225 | * Verification Tag: | |
3226 | * | |
3227 | * The return value is the disposition of the chunk. | |
3228 | */ | |
24cb81a6 EB |
3229 | static sctp_disposition_t sctp_sf_tabort_8_4_8(struct net *net, |
3230 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3231 | const struct sctp_association *asoc, |
3232 | const sctp_subtype_t type, | |
3233 | void *arg, | |
3234 | sctp_cmd_seq_t *commands) | |
3235 | { | |
3236 | struct sctp_packet *packet = NULL; | |
3237 | struct sctp_chunk *chunk = arg; | |
3238 | struct sctp_chunk *abort; | |
3239 | ||
2ce95503 | 3240 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
1da177e4 LT |
3241 | |
3242 | if (packet) { | |
3243 | /* Make an ABORT. The T bit will be set if the asoc | |
3244 | * is NULL. | |
3245 | */ | |
d808ad9a | 3246 | abort = sctp_make_abort(asoc, chunk, 0); |
1da177e4 LT |
3247 | if (!abort) { |
3248 | sctp_ootb_pkt_free(packet); | |
3249 | return SCTP_DISPOSITION_NOMEM; | |
3250 | } | |
3251 | ||
047a2428 JF |
3252 | /* Reflect vtag if T-Bit is set */ |
3253 | if (sctp_test_T_bit(abort)) | |
3254 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
3255 | ||
1da177e4 LT |
3256 | /* Set the skb to the belonging sock for accounting. */ |
3257 | abort->skb->sk = ep->base.sk; | |
3258 | ||
3259 | sctp_packet_append_chunk(packet, abort); | |
3260 | ||
3261 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
3262 | SCTP_PACKET(packet)); | |
3263 | ||
b01a2407 | 3264 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 | 3265 | |
24cb81a6 | 3266 | sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3267 | return SCTP_DISPOSITION_CONSUME; |
3268 | } | |
3269 | ||
3270 | return SCTP_DISPOSITION_NOMEM; | |
3271 | } | |
3272 | ||
3273 | /* | |
3274 | * Received an ERROR chunk from peer. Generate SCTP_REMOTE_ERROR | |
3275 | * event as ULP notification for each cause included in the chunk. | |
3276 | * | |
3277 | * API 5.3.1.3 - SCTP_REMOTE_ERROR | |
3278 | * | |
3279 | * The return value is the disposition of the chunk. | |
3280 | */ | |
24cb81a6 EB |
3281 | sctp_disposition_t sctp_sf_operr_notify(struct net *net, |
3282 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3283 | const struct sctp_association *asoc, |
3284 | const sctp_subtype_t type, | |
3285 | void *arg, | |
3286 | sctp_cmd_seq_t *commands) | |
3287 | { | |
3288 | struct sctp_chunk *chunk = arg; | |
8a00be1c | 3289 | sctp_errhdr_t *err; |
1da177e4 LT |
3290 | |
3291 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 3292 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3293 | |
3294 | /* Make sure that the ERROR chunk has a valid length. */ | |
3295 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t))) | |
24cb81a6 | 3296 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 | 3297 | commands); |
8a00be1c SW |
3298 | sctp_walk_errors(err, chunk->chunk_hdr); |
3299 | if ((void *)err != (void *)chunk->chunk_end) | |
24cb81a6 | 3300 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, |
8a00be1c | 3301 | (void *)err, commands); |
1da177e4 | 3302 | |
3df26787 WY |
3303 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_OPERR, |
3304 | SCTP_CHUNK(chunk)); | |
1da177e4 | 3305 | |
1da177e4 | 3306 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
3307 | } |
3308 | ||
3309 | /* | |
3310 | * Process an inbound SHUTDOWN ACK. | |
3311 | * | |
3312 | * From Section 9.2: | |
3313 | * Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3314 | * stop the T2-shutdown timer, send a SHUTDOWN COMPLETE chunk to its | |
3315 | * peer, and remove all record of the association. | |
3316 | * | |
3317 | * The return value is the disposition. | |
3318 | */ | |
24cb81a6 EB |
3319 | sctp_disposition_t sctp_sf_do_9_2_final(struct net *net, |
3320 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3321 | const struct sctp_association *asoc, |
3322 | const sctp_subtype_t type, | |
3323 | void *arg, | |
3324 | sctp_cmd_seq_t *commands) | |
3325 | { | |
3326 | struct sctp_chunk *chunk = arg; | |
3327 | struct sctp_chunk *reply; | |
3328 | struct sctp_ulpevent *ev; | |
3329 | ||
3330 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 3331 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3332 | |
3333 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
3334 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 3335 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 | 3336 | commands); |
1da177e4 LT |
3337 | /* 10.2 H) SHUTDOWN COMPLETE notification |
3338 | * | |
3339 | * When SCTP completes the shutdown procedures (section 9.2) this | |
3340 | * notification is passed to the upper layer. | |
3341 | */ | |
3342 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP, | |
a5a35e76 | 3343 | 0, 0, 0, NULL, GFP_ATOMIC); |
1da177e4 LT |
3344 | if (!ev) |
3345 | goto nomem; | |
3346 | ||
df7deeb5 VY |
3347 | /* ...send a SHUTDOWN COMPLETE chunk to its peer, */ |
3348 | reply = sctp_make_shutdown_complete(asoc, chunk); | |
3349 | if (!reply) | |
3350 | goto nomem_chunk; | |
3351 | ||
3352 | /* Do all the commands now (after allocation), so that we | |
3353 | * have consistent state if memory allocation failes | |
3354 | */ | |
1da177e4 LT |
3355 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
3356 | ||
3357 | /* Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3358 | * stop the T2-shutdown timer, | |
3359 | */ | |
3360 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3361 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3362 | ||
3363 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3364 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
3365 | ||
1da177e4 LT |
3366 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
3367 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
b01a2407 EB |
3368 | SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS); |
3369 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
3370 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); |
3371 | ||
3372 | /* ...and remove all record of the association. */ | |
3373 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
3374 | return SCTP_DISPOSITION_DELETE_TCB; | |
3375 | ||
df7deeb5 VY |
3376 | nomem_chunk: |
3377 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
3378 | nomem: |
3379 | return SCTP_DISPOSITION_NOMEM; | |
3380 | } | |
3381 | ||
3382 | /* | |
047a2428 JF |
3383 | * RFC 2960, 8.4 - Handle "Out of the blue" Packets, sctpimpguide 2.41. |
3384 | * | |
1da177e4 LT |
3385 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
3386 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. | |
3387 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3388 | * packet must fill in the Verification Tag field of the outbound | |
3389 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
047a2428 JF |
3390 | * set the T-bit in the Chunk Flags to indicate that the Verification |
3391 | * Tag is reflected. | |
1da177e4 LT |
3392 | * |
3393 | * 8) The receiver should respond to the sender of the OOTB packet with | |
3394 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
3395 | * MUST fill in the Verification Tag field of the outbound packet | |
3396 | * with the value found in the Verification Tag field of the OOTB | |
047a2428 JF |
3397 | * packet and set the T-bit in the Chunk Flags to indicate that the |
3398 | * Verification Tag is reflected. After sending this ABORT, the | |
3399 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
3400 | * no further action. | |
1da177e4 | 3401 | */ |
24cb81a6 EB |
3402 | sctp_disposition_t sctp_sf_ootb(struct net *net, |
3403 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3404 | const struct sctp_association *asoc, |
3405 | const sctp_subtype_t type, | |
3406 | void *arg, | |
3407 | sctp_cmd_seq_t *commands) | |
3408 | { | |
3409 | struct sctp_chunk *chunk = arg; | |
3410 | struct sk_buff *skb = chunk->skb; | |
3411 | sctp_chunkhdr_t *ch; | |
85c5ed4e | 3412 | sctp_errhdr_t *err; |
1da177e4 LT |
3413 | __u8 *ch_end; |
3414 | int ootb_shut_ack = 0; | |
85c5ed4e | 3415 | int ootb_cookie_ack = 0; |
1da177e4 | 3416 | |
b01a2407 | 3417 | SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES); |
1da177e4 LT |
3418 | |
3419 | ch = (sctp_chunkhdr_t *) chunk->chunk_hdr; | |
3420 | do { | |
ece25dfa | 3421 | /* Report violation if the chunk is less then minimal */ |
1da177e4 | 3422 | if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t)) |
24cb81a6 | 3423 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa | 3424 | commands); |
1da177e4 | 3425 | |
ece25dfa VY |
3426 | /* Now that we know we at least have a chunk header, |
3427 | * do things that are type appropriate. | |
3428 | */ | |
1da177e4 LT |
3429 | if (SCTP_CID_SHUTDOWN_ACK == ch->type) |
3430 | ootb_shut_ack = 1; | |
3431 | ||
3432 | /* RFC 2960, Section 3.3.7 | |
3433 | * Moreover, under any circumstances, an endpoint that | |
3434 | * receives an ABORT MUST NOT respond to that ABORT by | |
3435 | * sending an ABORT of its own. | |
3436 | */ | |
3437 | if (SCTP_CID_ABORT == ch->type) | |
24cb81a6 | 3438 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
d808ad9a | 3439 | |
85c5ed4e SW |
3440 | /* RFC 8.4, 7) If the packet contains a "Stale cookie" ERROR |
3441 | * or a COOKIE ACK the SCTP Packet should be silently | |
3442 | * discarded. | |
3443 | */ | |
3444 | ||
3445 | if (SCTP_CID_COOKIE_ACK == ch->type) | |
3446 | ootb_cookie_ack = 1; | |
3447 | ||
3448 | if (SCTP_CID_ERROR == ch->type) { | |
3449 | sctp_walk_errors(err, ch) { | |
3450 | if (SCTP_ERROR_STALE_COOKIE == err->cause) { | |
3451 | ootb_cookie_ack = 1; | |
3452 | break; | |
3453 | } | |
3454 | } | |
3455 | } | |
3456 | ||
ece25dfa VY |
3457 | /* Report violation if chunk len overflows */ |
3458 | ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length)); | |
3459 | if (ch_end > skb_tail_pointer(skb)) | |
24cb81a6 | 3460 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa VY |
3461 | commands); |
3462 | ||
1da177e4 | 3463 | ch = (sctp_chunkhdr_t *) ch_end; |
27a884dc | 3464 | } while (ch_end < skb_tail_pointer(skb)); |
1da177e4 LT |
3465 | |
3466 | if (ootb_shut_ack) | |
24cb81a6 | 3467 | return sctp_sf_shut_8_4_5(net, ep, asoc, type, arg, commands); |
85c5ed4e | 3468 | else if (ootb_cookie_ack) |
24cb81a6 | 3469 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 3470 | else |
24cb81a6 | 3471 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3472 | } |
3473 | ||
3474 | /* | |
3475 | * Handle an "Out of the blue" SHUTDOWN ACK. | |
3476 | * | |
047a2428 JF |
3477 | * Section: 8.4 5, sctpimpguide 2.41. |
3478 | * | |
1da177e4 | 3479 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
047a2428 JF |
3480 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. |
3481 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3482 | * packet must fill in the Verification Tag field of the outbound | |
3483 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
3484 | * set the T-bit in the Chunk Flags to indicate that the Verification | |
3485 | * Tag is reflected. | |
1da177e4 LT |
3486 | * |
3487 | * Inputs | |
3488 | * (endpoint, asoc, type, arg, commands) | |
3489 | * | |
3490 | * Outputs | |
3491 | * (sctp_disposition_t) | |
3492 | * | |
3493 | * The return value is the disposition of the chunk. | |
3494 | */ | |
24cb81a6 EB |
3495 | static sctp_disposition_t sctp_sf_shut_8_4_5(struct net *net, |
3496 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3497 | const struct sctp_association *asoc, |
3498 | const sctp_subtype_t type, | |
3499 | void *arg, | |
3500 | sctp_cmd_seq_t *commands) | |
3501 | { | |
3502 | struct sctp_packet *packet = NULL; | |
3503 | struct sctp_chunk *chunk = arg; | |
3504 | struct sctp_chunk *shut; | |
3505 | ||
2ce95503 | 3506 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
1da177e4 LT |
3507 | |
3508 | if (packet) { | |
3509 | /* Make an SHUTDOWN_COMPLETE. | |
d808ad9a YH |
3510 | * The T bit will be set if the asoc is NULL. |
3511 | */ | |
1da177e4 LT |
3512 | shut = sctp_make_shutdown_complete(asoc, chunk); |
3513 | if (!shut) { | |
3514 | sctp_ootb_pkt_free(packet); | |
3515 | return SCTP_DISPOSITION_NOMEM; | |
3516 | } | |
3517 | ||
047a2428 JF |
3518 | /* Reflect vtag if T-Bit is set */ |
3519 | if (sctp_test_T_bit(shut)) | |
3520 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
3521 | ||
1da177e4 LT |
3522 | /* Set the skb to the belonging sock for accounting. */ |
3523 | shut->skb->sk = ep->base.sk; | |
3524 | ||
3525 | sctp_packet_append_chunk(packet, shut); | |
3526 | ||
3527 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
3528 | SCTP_PACKET(packet)); | |
3529 | ||
b01a2407 | 3530 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
3531 | |
3532 | /* If the chunk length is invalid, we don't want to process | |
3533 | * the reset of the packet. | |
3534 | */ | |
3535 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 3536 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 3537 | |
d3f25968 VY |
3538 | /* We need to discard the rest of the packet to prevent |
3539 | * potential bomming attacks from additional bundled chunks. | |
3540 | * This is documented in SCTP Threats ID. | |
3541 | */ | |
24cb81a6 | 3542 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3543 | } |
3544 | ||
3545 | return SCTP_DISPOSITION_NOMEM; | |
3546 | } | |
3547 | ||
3548 | /* | |
3549 | * Handle SHUTDOWN ACK in COOKIE_ECHOED or COOKIE_WAIT state. | |
3550 | * | |
3551 | * Verification Tag: 8.5.1 E) Rules for packet carrying a SHUTDOWN ACK | |
3552 | * If the receiver is in COOKIE-ECHOED or COOKIE-WAIT state the | |
3553 | * procedures in section 8.4 SHOULD be followed, in other words it | |
3554 | * should be treated as an Out Of The Blue packet. | |
3555 | * [This means that we do NOT check the Verification Tag on these | |
3556 | * chunks. --piggy ] | |
3557 | * | |
3558 | */ | |
24cb81a6 EB |
3559 | sctp_disposition_t sctp_sf_do_8_5_1_E_sa(struct net *net, |
3560 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3561 | const struct sctp_association *asoc, |
3562 | const sctp_subtype_t type, | |
3563 | void *arg, | |
3564 | sctp_cmd_seq_t *commands) | |
3565 | { | |
ece25dfa VY |
3566 | struct sctp_chunk *chunk = arg; |
3567 | ||
3568 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
3569 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 3570 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa VY |
3571 | commands); |
3572 | ||
1da177e4 LT |
3573 | /* Although we do have an association in this case, it corresponds |
3574 | * to a restarted association. So the packet is treated as an OOTB | |
3575 | * packet and the state function that handles OOTB SHUTDOWN_ACK is | |
3576 | * called with a NULL association. | |
3577 | */ | |
24cb81a6 | 3578 | SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES); |
8190f89d | 3579 | |
24cb81a6 | 3580 | return sctp_sf_shut_8_4_5(net, ep, NULL, type, arg, commands); |
1da177e4 LT |
3581 | } |
3582 | ||
3583 | /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. */ | |
24cb81a6 EB |
3584 | sctp_disposition_t sctp_sf_do_asconf(struct net *net, |
3585 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3586 | const struct sctp_association *asoc, |
3587 | const sctp_subtype_t type, void *arg, | |
3588 | sctp_cmd_seq_t *commands) | |
3589 | { | |
3590 | struct sctp_chunk *chunk = arg; | |
3591 | struct sctp_chunk *asconf_ack = NULL; | |
6f4c618d | 3592 | struct sctp_paramhdr *err_param = NULL; |
1da177e4 | 3593 | sctp_addiphdr_t *hdr; |
6f4c618d | 3594 | union sctp_addr_param *addr_param; |
1da177e4 | 3595 | __u32 serial; |
6f4c618d | 3596 | int length; |
1da177e4 LT |
3597 | |
3598 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3599 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3600 | SCTP_NULL()); | |
24cb81a6 | 3601 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3602 | } |
3603 | ||
6afd2e83 VY |
3604 | /* ADD-IP: Section 4.1.1 |
3605 | * This chunk MUST be sent in an authenticated way by using | |
3606 | * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk | |
3607 | * is received unauthenticated it MUST be silently discarded as | |
3608 | * described in [I-D.ietf-tsvwg-sctp-auth]. | |
3609 | */ | |
e1fc3b14 | 3610 | if (!net->sctp.addip_noauth && !chunk->auth) |
24cb81a6 | 3611 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
6afd2e83 | 3612 | |
1da177e4 LT |
3613 | /* Make sure that the ASCONF ADDIP chunk has a valid length. */ |
3614 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_addip_chunk_t))) | |
24cb81a6 | 3615 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3616 | commands); |
3617 | ||
3618 | hdr = (sctp_addiphdr_t *)chunk->skb->data; | |
3619 | serial = ntohl(hdr->serial); | |
3620 | ||
6f4c618d WY |
3621 | addr_param = (union sctp_addr_param *)hdr->params; |
3622 | length = ntohs(addr_param->p.length); | |
3623 | if (length < sizeof(sctp_paramhdr_t)) | |
24cb81a6 | 3624 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, |
6f4c618d WY |
3625 | (void *)addr_param, commands); |
3626 | ||
3627 | /* Verify the ASCONF chunk before processing it. */ | |
3628 | if (!sctp_verify_asconf(asoc, | |
a08de64d VY |
3629 | (sctp_paramhdr_t *)((void *)addr_param + length), |
3630 | (void *)chunk->chunk_end, | |
3631 | &err_param)) | |
24cb81a6 | 3632 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, |
ba016670 | 3633 | (void *)err_param, commands); |
6f4c618d | 3634 | |
a08de64d | 3635 | /* ADDIP 5.2 E1) Compare the value of the serial number to the value |
1da177e4 | 3636 | * the endpoint stored in a new association variable |
d808ad9a | 3637 | * 'Peer-Serial-Number'. |
1da177e4 LT |
3638 | */ |
3639 | if (serial == asoc->peer.addip_serial + 1) { | |
a08de64d VY |
3640 | /* If this is the first instance of ASCONF in the packet, |
3641 | * we can clean our old ASCONF-ACKs. | |
3642 | */ | |
3643 | if (!chunk->has_asconf) | |
3644 | sctp_assoc_clean_asconf_ack_cache(asoc); | |
3645 | ||
3646 | /* ADDIP 5.2 E4) When the Sequence Number matches the next one | |
3647 | * expected, process the ASCONF as described below and after | |
3648 | * processing the ASCONF Chunk, append an ASCONF-ACK Chunk to | |
3649 | * the response packet and cache a copy of it (in the event it | |
3650 | * later needs to be retransmitted). | |
3651 | * | |
3652 | * Essentially, do V1-V5. | |
1da177e4 LT |
3653 | */ |
3654 | asconf_ack = sctp_process_asconf((struct sctp_association *) | |
3655 | asoc, chunk); | |
3656 | if (!asconf_ack) | |
3657 | return SCTP_DISPOSITION_NOMEM; | |
a08de64d VY |
3658 | } else if (serial < asoc->peer.addip_serial + 1) { |
3659 | /* ADDIP 5.2 E2) | |
3660 | * If the value found in the Sequence Number is less than the | |
3661 | * ('Peer- Sequence-Number' + 1), simply skip to the next | |
3662 | * ASCONF, and include in the outbound response packet | |
3663 | * any previously cached ASCONF-ACK response that was | |
3664 | * sent and saved that matches the Sequence Number of the | |
3665 | * ASCONF. Note: It is possible that no cached ASCONF-ACK | |
3666 | * Chunk exists. This will occur when an older ASCONF | |
3667 | * arrives out of order. In such a case, the receiver | |
3668 | * should skip the ASCONF Chunk and not include ASCONF-ACK | |
3669 | * Chunk for that chunk. | |
1da177e4 | 3670 | */ |
a08de64d VY |
3671 | asconf_ack = sctp_assoc_lookup_asconf_ack(asoc, hdr->serial); |
3672 | if (!asconf_ack) | |
1da177e4 | 3673 | return SCTP_DISPOSITION_DISCARD; |
31b02e15 VY |
3674 | |
3675 | /* Reset the transport so that we select the correct one | |
3676 | * this time around. This is to make sure that we don't | |
3677 | * accidentally use a stale transport that's been removed. | |
3678 | */ | |
3679 | asconf_ack->transport = NULL; | |
1da177e4 | 3680 | } else { |
a08de64d | 3681 | /* ADDIP 5.2 E5) Otherwise, the ASCONF Chunk is discarded since |
1da177e4 | 3682 | * it must be either a stale packet or from an attacker. |
d808ad9a | 3683 | */ |
1da177e4 LT |
3684 | return SCTP_DISPOSITION_DISCARD; |
3685 | } | |
3686 | ||
a08de64d VY |
3687 | /* ADDIP 5.2 E6) The destination address of the SCTP packet |
3688 | * containing the ASCONF-ACK Chunks MUST be the source address of | |
3689 | * the SCTP packet that held the ASCONF Chunks. | |
3690 | * | |
3691 | * To do this properly, we'll set the destination address of the chunk | |
3692 | * and at the transmit time, will try look up the transport to use. | |
3693 | * Since ASCONFs may be bundled, the correct transport may not be | |
94e2bd68 | 3694 | * created until we process the entire packet, thus this workaround. |
1da177e4 | 3695 | */ |
a08de64d | 3696 | asconf_ack->dest = chunk->source; |
1da177e4 | 3697 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(asconf_ack)); |
6af29ccc | 3698 | if (asoc->new_transport) { |
f7010e61 | 3699 | sctp_sf_heartbeat(ep, asoc, type, asoc->new_transport, commands); |
6af29ccc MH |
3700 | ((struct sctp_association *)asoc)->new_transport = NULL; |
3701 | } | |
d808ad9a | 3702 | |
1da177e4 LT |
3703 | return SCTP_DISPOSITION_CONSUME; |
3704 | } | |
3705 | ||
3706 | /* | |
3707 | * ADDIP Section 4.3 General rules for address manipulation | |
3708 | * When building TLV parameters for the ASCONF Chunk that will add or | |
3709 | * delete IP addresses the D0 to D13 rules should be applied: | |
3710 | */ | |
24cb81a6 EB |
3711 | sctp_disposition_t sctp_sf_do_asconf_ack(struct net *net, |
3712 | const struct sctp_endpoint *ep, | |
1da177e4 | 3713 | const struct sctp_association *asoc, |
d808ad9a | 3714 | const sctp_subtype_t type, void *arg, |
1da177e4 LT |
3715 | sctp_cmd_seq_t *commands) |
3716 | { | |
3717 | struct sctp_chunk *asconf_ack = arg; | |
3718 | struct sctp_chunk *last_asconf = asoc->addip_last_asconf; | |
3719 | struct sctp_chunk *abort; | |
6f4c618d | 3720 | struct sctp_paramhdr *err_param = NULL; |
1da177e4 LT |
3721 | sctp_addiphdr_t *addip_hdr; |
3722 | __u32 sent_serial, rcvd_serial; | |
3723 | ||
3724 | if (!sctp_vtag_verify(asconf_ack, asoc)) { | |
3725 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3726 | SCTP_NULL()); | |
24cb81a6 | 3727 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3728 | } |
3729 | ||
6afd2e83 VY |
3730 | /* ADD-IP, Section 4.1.2: |
3731 | * This chunk MUST be sent in an authenticated way by using | |
3732 | * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk | |
3733 | * is received unauthenticated it MUST be silently discarded as | |
3734 | * described in [I-D.ietf-tsvwg-sctp-auth]. | |
3735 | */ | |
e1fc3b14 | 3736 | if (!net->sctp.addip_noauth && !asconf_ack->auth) |
24cb81a6 | 3737 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
6afd2e83 | 3738 | |
1da177e4 LT |
3739 | /* Make sure that the ADDIP chunk has a valid length. */ |
3740 | if (!sctp_chunk_length_valid(asconf_ack, sizeof(sctp_addip_chunk_t))) | |
24cb81a6 | 3741 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3742 | commands); |
3743 | ||
3744 | addip_hdr = (sctp_addiphdr_t *)asconf_ack->skb->data; | |
3745 | rcvd_serial = ntohl(addip_hdr->serial); | |
3746 | ||
6f4c618d WY |
3747 | /* Verify the ASCONF-ACK chunk before processing it. */ |
3748 | if (!sctp_verify_asconf(asoc, | |
3749 | (sctp_paramhdr_t *)addip_hdr->params, | |
3750 | (void *)asconf_ack->chunk_end, | |
3751 | &err_param)) | |
24cb81a6 | 3752 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, |
ba016670 | 3753 | (void *)err_param, commands); |
6f4c618d | 3754 | |
1da177e4 LT |
3755 | if (last_asconf) { |
3756 | addip_hdr = (sctp_addiphdr_t *)last_asconf->subh.addip_hdr; | |
3757 | sent_serial = ntohl(addip_hdr->serial); | |
3758 | } else { | |
3759 | sent_serial = asoc->addip_serial - 1; | |
3760 | } | |
3761 | ||
3762 | /* D0) If an endpoint receives an ASCONF-ACK that is greater than or | |
3763 | * equal to the next serial number to be used but no ASCONF chunk is | |
3764 | * outstanding the endpoint MUST ABORT the association. Note that a | |
3765 | * sequence number is greater than if it is no more than 2^^31-1 | |
3766 | * larger than the current sequence number (using serial arithmetic). | |
3767 | */ | |
3768 | if (ADDIP_SERIAL_gte(rcvd_serial, sent_serial + 1) && | |
3769 | !(asoc->addip_last_asconf)) { | |
3770 | abort = sctp_make_abort(asoc, asconf_ack, | |
3771 | sizeof(sctp_errhdr_t)); | |
3772 | if (abort) { | |
00f1c2df | 3773 | sctp_init_cause(abort, SCTP_ERROR_ASCONF_ACK, 0); |
1da177e4 LT |
3774 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3775 | SCTP_CHUNK(abort)); | |
3776 | } | |
3777 | /* We are going to ABORT, so we might as well stop | |
3778 | * processing the rest of the chunks in the packet. | |
3779 | */ | |
3780 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3781 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
cb3f837b | 3782 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
8de8c873 | 3783 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3784 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3785 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3786 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
b01a2407 EB |
3787 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
3788 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
3789 | return SCTP_DISPOSITION_ABORT; |
3790 | } | |
3791 | ||
3792 | if ((rcvd_serial == sent_serial) && asoc->addip_last_asconf) { | |
3793 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3794 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
3795 | ||
3796 | if (!sctp_process_asconf_ack((struct sctp_association *)asoc, | |
c0786693 VY |
3797 | asconf_ack)) { |
3798 | /* Successfully processed ASCONF_ACK. We can | |
3799 | * release the next asconf if we have one. | |
3800 | */ | |
3801 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_NEXT_ASCONF, | |
3802 | SCTP_NULL()); | |
1da177e4 | 3803 | return SCTP_DISPOSITION_CONSUME; |
c0786693 | 3804 | } |
1da177e4 LT |
3805 | |
3806 | abort = sctp_make_abort(asoc, asconf_ack, | |
3807 | sizeof(sctp_errhdr_t)); | |
3808 | if (abort) { | |
00f1c2df | 3809 | sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0); |
1da177e4 LT |
3810 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3811 | SCTP_CHUNK(abort)); | |
3812 | } | |
3813 | /* We are going to ABORT, so we might as well stop | |
3814 | * processing the rest of the chunks in the packet. | |
3815 | */ | |
cb3f837b | 3816 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
8de8c873 | 3817 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3818 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3819 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3820 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
b01a2407 EB |
3821 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
3822 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
3823 | return SCTP_DISPOSITION_ABORT; |
3824 | } | |
3825 | ||
3826 | return SCTP_DISPOSITION_DISCARD; | |
3827 | } | |
3828 | ||
3829 | /* | |
3830 | * PR-SCTP Section 3.6 Receiver Side Implementation of PR-SCTP | |
3831 | * | |
3832 | * When a FORWARD TSN chunk arrives, the data receiver MUST first update | |
3833 | * its cumulative TSN point to the value carried in the FORWARD TSN | |
3834 | * chunk, and then MUST further advance its cumulative TSN point locally | |
3835 | * if possible. | |
3836 | * After the above processing, the data receiver MUST stop reporting any | |
3837 | * missing TSNs earlier than or equal to the new cumulative TSN point. | |
3838 | * | |
3839 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3840 | * | |
3841 | * The return value is the disposition of the chunk. | |
3842 | */ | |
24cb81a6 EB |
3843 | sctp_disposition_t sctp_sf_eat_fwd_tsn(struct net *net, |
3844 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
3845 | const struct sctp_association *asoc, |
3846 | const sctp_subtype_t type, | |
3847 | void *arg, | |
3848 | sctp_cmd_seq_t *commands) | |
3849 | { | |
3850 | struct sctp_chunk *chunk = arg; | |
3851 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; | |
9fcb95a1 | 3852 | struct sctp_fwdtsn_skip *skip; |
1da177e4 LT |
3853 | __u16 len; |
3854 | __u32 tsn; | |
3855 | ||
3856 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3857 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3858 | SCTP_NULL()); | |
24cb81a6 | 3859 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3860 | } |
3861 | ||
3862 | /* Make sure that the FORWARD_TSN chunk has valid length. */ | |
3863 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk))) | |
24cb81a6 | 3864 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3865 | commands); |
3866 | ||
3867 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
3868 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
3869 | len = ntohs(chunk->chunk_hdr->length); | |
3870 | len -= sizeof(struct sctp_chunkhdr); | |
3871 | skb_pull(chunk->skb, len); | |
3872 | ||
3873 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
bb33381d | 3874 | pr_debug("%s: TSN 0x%x\n", __func__, tsn); |
1da177e4 LT |
3875 | |
3876 | /* The TSN is too high--silently discard the chunk and count on it | |
3877 | * getting retransmitted later. | |
3878 | */ | |
3879 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
3880 | goto discard_noforce; | |
3881 | ||
9fcb95a1 WY |
3882 | /* Silently discard the chunk if stream-id is not valid */ |
3883 | sctp_walk_fwdtsn(skip, chunk) { | |
3884 | if (ntohs(skip->stream) >= asoc->c.sinit_max_instreams) | |
3885 | goto discard_noforce; | |
3886 | } | |
3887 | ||
1da177e4 LT |
3888 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); |
3889 | if (len > sizeof(struct sctp_fwdtsn_hdr)) | |
d808ad9a | 3890 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 3891 | SCTP_CHUNK(chunk)); |
d808ad9a | 3892 | |
1da177e4 | 3893 | /* Count this as receiving DATA. */ |
9f70f46b | 3894 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) { |
1da177e4 LT |
3895 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, |
3896 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
3897 | } | |
d808ad9a | 3898 | |
1da177e4 | 3899 | /* FIXME: For now send a SACK, but DATA processing may |
d808ad9a | 3900 | * send another. |
1da177e4 LT |
3901 | */ |
3902 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE()); | |
1da177e4 LT |
3903 | |
3904 | return SCTP_DISPOSITION_CONSUME; | |
3905 | ||
3906 | discard_noforce: | |
3907 | return SCTP_DISPOSITION_DISCARD; | |
3908 | } | |
3909 | ||
3910 | sctp_disposition_t sctp_sf_eat_fwd_tsn_fast( | |
24cb81a6 | 3911 | struct net *net, |
1da177e4 LT |
3912 | const struct sctp_endpoint *ep, |
3913 | const struct sctp_association *asoc, | |
3914 | const sctp_subtype_t type, | |
3915 | void *arg, | |
3916 | sctp_cmd_seq_t *commands) | |
3917 | { | |
3918 | struct sctp_chunk *chunk = arg; | |
3919 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; | |
9fcb95a1 | 3920 | struct sctp_fwdtsn_skip *skip; |
1da177e4 LT |
3921 | __u16 len; |
3922 | __u32 tsn; | |
3923 | ||
3924 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3925 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3926 | SCTP_NULL()); | |
24cb81a6 | 3927 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3928 | } |
3929 | ||
3930 | /* Make sure that the FORWARD_TSN chunk has a valid length. */ | |
3931 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk))) | |
24cb81a6 | 3932 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3933 | commands); |
3934 | ||
3935 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
3936 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
3937 | len = ntohs(chunk->chunk_hdr->length); | |
3938 | len -= sizeof(struct sctp_chunkhdr); | |
3939 | skb_pull(chunk->skb, len); | |
3940 | ||
3941 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
bb33381d | 3942 | pr_debug("%s: TSN 0x%x\n", __func__, tsn); |
1da177e4 LT |
3943 | |
3944 | /* The TSN is too high--silently discard the chunk and count on it | |
3945 | * getting retransmitted later. | |
3946 | */ | |
3947 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
3948 | goto gen_shutdown; | |
3949 | ||
9fcb95a1 WY |
3950 | /* Silently discard the chunk if stream-id is not valid */ |
3951 | sctp_walk_fwdtsn(skip, chunk) { | |
3952 | if (ntohs(skip->stream) >= asoc->c.sinit_max_instreams) | |
3953 | goto gen_shutdown; | |
3954 | } | |
3955 | ||
1da177e4 LT |
3956 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); |
3957 | if (len > sizeof(struct sctp_fwdtsn_hdr)) | |
d808ad9a | 3958 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 3959 | SCTP_CHUNK(chunk)); |
d808ad9a | 3960 | |
1da177e4 LT |
3961 | /* Go a head and force a SACK, since we are shutting down. */ |
3962 | gen_shutdown: | |
3963 | /* Implementor's Guide. | |
3964 | * | |
3965 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
3966 | * respond to each received packet containing one or more DATA chunk(s) | |
3967 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
3968 | */ | |
3969 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
3970 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
3971 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3972 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3973 | ||
d808ad9a | 3974 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
3975 | } |
3976 | ||
bbd0d598 | 3977 | /* |
25985edc | 3978 | * SCTP-AUTH Section 6.3 Receiving authenticated chukns |
bbd0d598 VY |
3979 | * |
3980 | * The receiver MUST use the HMAC algorithm indicated in the HMAC | |
3981 | * Identifier field. If this algorithm was not specified by the | |
3982 | * receiver in the HMAC-ALGO parameter in the INIT or INIT-ACK chunk | |
3983 | * during association setup, the AUTH chunk and all chunks after it MUST | |
3984 | * be discarded and an ERROR chunk SHOULD be sent with the error cause | |
3985 | * defined in Section 4.1. | |
3986 | * | |
3987 | * If an endpoint with no shared key receives a Shared Key Identifier | |
3988 | * other than 0, it MUST silently discard all authenticated chunks. If | |
3989 | * the endpoint has at least one endpoint pair shared key for the peer, | |
3990 | * it MUST use the key specified by the Shared Key Identifier if a | |
3991 | * key has been configured for that Shared Key Identifier. If no | |
3992 | * endpoint pair shared key has been configured for that Shared Key | |
3993 | * Identifier, all authenticated chunks MUST be silently discarded. | |
3994 | * | |
3995 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3996 | * | |
3997 | * The return value is the disposition of the chunk. | |
3998 | */ | |
24cb81a6 EB |
3999 | static sctp_ierror_t sctp_sf_authenticate(struct net *net, |
4000 | const struct sctp_endpoint *ep, | |
bbd0d598 VY |
4001 | const struct sctp_association *asoc, |
4002 | const sctp_subtype_t type, | |
4003 | struct sctp_chunk *chunk) | |
4004 | { | |
4005 | struct sctp_authhdr *auth_hdr; | |
4006 | struct sctp_hmac *hmac; | |
4007 | unsigned int sig_len; | |
4008 | __u16 key_id; | |
4009 | __u8 *save_digest; | |
4010 | __u8 *digest; | |
4011 | ||
4012 | /* Pull in the auth header, so we can do some more verification */ | |
4013 | auth_hdr = (struct sctp_authhdr *)chunk->skb->data; | |
4014 | chunk->subh.auth_hdr = auth_hdr; | |
4015 | skb_pull(chunk->skb, sizeof(struct sctp_authhdr)); | |
4016 | ||
02582e9b | 4017 | /* Make sure that we support the HMAC algorithm from the auth |
bbd0d598 VY |
4018 | * chunk. |
4019 | */ | |
4020 | if (!sctp_auth_asoc_verify_hmac_id(asoc, auth_hdr->hmac_id)) | |
4021 | return SCTP_IERROR_AUTH_BAD_HMAC; | |
4022 | ||
4023 | /* Make sure that the provided shared key identifier has been | |
4024 | * configured | |
4025 | */ | |
4026 | key_id = ntohs(auth_hdr->shkey_id); | |
4027 | if (key_id != asoc->active_key_id && !sctp_auth_get_shkey(asoc, key_id)) | |
4028 | return SCTP_IERROR_AUTH_BAD_KEYID; | |
4029 | ||
4030 | ||
4031 | /* Make sure that the length of the signature matches what | |
4032 | * we expect. | |
4033 | */ | |
4034 | sig_len = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_auth_chunk_t); | |
4035 | hmac = sctp_auth_get_hmac(ntohs(auth_hdr->hmac_id)); | |
4036 | if (sig_len != hmac->hmac_len) | |
4037 | return SCTP_IERROR_PROTO_VIOLATION; | |
4038 | ||
4039 | /* Now that we've done validation checks, we can compute and | |
4040 | * verify the hmac. The steps involved are: | |
4041 | * 1. Save the digest from the chunk. | |
4042 | * 2. Zero out the digest in the chunk. | |
4043 | * 3. Compute the new digest | |
4044 | * 4. Compare saved and new digests. | |
4045 | */ | |
4046 | digest = auth_hdr->hmac; | |
4047 | skb_pull(chunk->skb, sig_len); | |
4048 | ||
4049 | save_digest = kmemdup(digest, sig_len, GFP_ATOMIC); | |
4050 | if (!save_digest) | |
4051 | goto nomem; | |
4052 | ||
4053 | memset(digest, 0, sig_len); | |
4054 | ||
4055 | sctp_auth_calculate_hmac(asoc, chunk->skb, | |
4056 | (struct sctp_auth_chunk *)chunk->chunk_hdr, | |
4057 | GFP_ATOMIC); | |
4058 | ||
4059 | /* Discard the packet if the digests do not match */ | |
4060 | if (memcmp(save_digest, digest, sig_len)) { | |
4061 | kfree(save_digest); | |
4062 | return SCTP_IERROR_BAD_SIG; | |
4063 | } | |
4064 | ||
4065 | kfree(save_digest); | |
4066 | chunk->auth = 1; | |
4067 | ||
4068 | return SCTP_IERROR_NO_ERROR; | |
4069 | nomem: | |
4070 | return SCTP_IERROR_NOMEM; | |
4071 | } | |
4072 | ||
24cb81a6 EB |
4073 | sctp_disposition_t sctp_sf_eat_auth(struct net *net, |
4074 | const struct sctp_endpoint *ep, | |
bbd0d598 VY |
4075 | const struct sctp_association *asoc, |
4076 | const sctp_subtype_t type, | |
4077 | void *arg, | |
4078 | sctp_cmd_seq_t *commands) | |
4079 | { | |
4080 | struct sctp_authhdr *auth_hdr; | |
4081 | struct sctp_chunk *chunk = arg; | |
4082 | struct sctp_chunk *err_chunk; | |
4083 | sctp_ierror_t error; | |
4084 | ||
d2f19fa1 WY |
4085 | /* Make sure that the peer has AUTH capable */ |
4086 | if (!asoc->peer.auth_capable) | |
24cb81a6 | 4087 | return sctp_sf_unk_chunk(net, ep, asoc, type, arg, commands); |
d2f19fa1 | 4088 | |
bbd0d598 VY |
4089 | if (!sctp_vtag_verify(chunk, asoc)) { |
4090 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
4091 | SCTP_NULL()); | |
24cb81a6 | 4092 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
bbd0d598 VY |
4093 | } |
4094 | ||
4095 | /* Make sure that the AUTH chunk has valid length. */ | |
4096 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_auth_chunk))) | |
24cb81a6 | 4097 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
bbd0d598 VY |
4098 | commands); |
4099 | ||
4100 | auth_hdr = (struct sctp_authhdr *)chunk->skb->data; | |
24cb81a6 | 4101 | error = sctp_sf_authenticate(net, ep, asoc, type, chunk); |
bbd0d598 | 4102 | switch (error) { |
7fd71b1e JP |
4103 | case SCTP_IERROR_AUTH_BAD_HMAC: |
4104 | /* Generate the ERROR chunk and discard the rest | |
4105 | * of the packet | |
4106 | */ | |
4107 | err_chunk = sctp_make_op_error(asoc, chunk, | |
4108 | SCTP_ERROR_UNSUP_HMAC, | |
4109 | &auth_hdr->hmac_id, | |
4110 | sizeof(__u16), 0); | |
4111 | if (err_chunk) { | |
4112 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
4113 | SCTP_CHUNK(err_chunk)); | |
4114 | } | |
4115 | /* Fall Through */ | |
4116 | case SCTP_IERROR_AUTH_BAD_KEYID: | |
4117 | case SCTP_IERROR_BAD_SIG: | |
24cb81a6 | 4118 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
7fd71b1e JP |
4119 | |
4120 | case SCTP_IERROR_PROTO_VIOLATION: | |
24cb81a6 | 4121 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
7fd71b1e JP |
4122 | commands); |
4123 | ||
4124 | case SCTP_IERROR_NOMEM: | |
4125 | return SCTP_DISPOSITION_NOMEM; | |
4126 | ||
4127 | default: /* Prevent gcc warnings */ | |
4128 | break; | |
bbd0d598 VY |
4129 | } |
4130 | ||
65b07e5d VY |
4131 | if (asoc->active_key_id != ntohs(auth_hdr->shkey_id)) { |
4132 | struct sctp_ulpevent *ev; | |
4133 | ||
4134 | ev = sctp_ulpevent_make_authkey(asoc, ntohs(auth_hdr->shkey_id), | |
4135 | SCTP_AUTH_NEWKEY, GFP_ATOMIC); | |
4136 | ||
4137 | if (!ev) | |
4138 | return -ENOMEM; | |
4139 | ||
4140 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
4141 | SCTP_ULPEVENT(ev)); | |
4142 | } | |
4143 | ||
bbd0d598 VY |
4144 | return SCTP_DISPOSITION_CONSUME; |
4145 | } | |
4146 | ||
1da177e4 LT |
4147 | /* |
4148 | * Process an unknown chunk. | |
4149 | * | |
4150 | * Section: 3.2. Also, 2.1 in the implementor's guide. | |
4151 | * | |
4152 | * Chunk Types are encoded such that the highest-order two bits specify | |
4153 | * the action that must be taken if the processing endpoint does not | |
4154 | * recognize the Chunk Type. | |
4155 | * | |
4156 | * 00 - Stop processing this SCTP packet and discard it, do not process | |
4157 | * any further chunks within it. | |
4158 | * | |
4159 | * 01 - Stop processing this SCTP packet and discard it, do not process | |
4160 | * any further chunks within it, and report the unrecognized | |
4161 | * chunk in an 'Unrecognized Chunk Type'. | |
4162 | * | |
4163 | * 10 - Skip this chunk and continue processing. | |
4164 | * | |
4165 | * 11 - Skip this chunk and continue processing, but report in an ERROR | |
4166 | * Chunk using the 'Unrecognized Chunk Type' cause of error. | |
4167 | * | |
4168 | * The return value is the disposition of the chunk. | |
4169 | */ | |
24cb81a6 EB |
4170 | sctp_disposition_t sctp_sf_unk_chunk(struct net *net, |
4171 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
4172 | const struct sctp_association *asoc, |
4173 | const sctp_subtype_t type, | |
4174 | void *arg, | |
4175 | sctp_cmd_seq_t *commands) | |
4176 | { | |
4177 | struct sctp_chunk *unk_chunk = arg; | |
4178 | struct sctp_chunk *err_chunk; | |
4179 | sctp_chunkhdr_t *hdr; | |
4180 | ||
bb33381d | 4181 | pr_debug("%s: processing unknown chunk id:%d\n", __func__, type.chunk); |
1da177e4 LT |
4182 | |
4183 | if (!sctp_vtag_verify(unk_chunk, asoc)) | |
24cb81a6 | 4184 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
4185 | |
4186 | /* Make sure that the chunk has a valid length. | |
4187 | * Since we don't know the chunk type, we use a general | |
4188 | * chunkhdr structure to make a comparison. | |
4189 | */ | |
4190 | if (!sctp_chunk_length_valid(unk_chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 4191 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
4192 | commands); |
4193 | ||
4194 | switch (type.chunk & SCTP_CID_ACTION_MASK) { | |
4195 | case SCTP_CID_ACTION_DISCARD: | |
4196 | /* Discard the packet. */ | |
24cb81a6 | 4197 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 4198 | case SCTP_CID_ACTION_DISCARD_ERR: |
1da177e4 LT |
4199 | /* Generate an ERROR chunk as response. */ |
4200 | hdr = unk_chunk->chunk_hdr; | |
4201 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
4202 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
6383cfb3 VY |
4203 | WORD_ROUND(ntohs(hdr->length)), |
4204 | 0); | |
1da177e4 LT |
4205 | if (err_chunk) { |
4206 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
4207 | SCTP_CHUNK(err_chunk)); | |
4208 | } | |
2e3216cd VY |
4209 | |
4210 | /* Discard the packet. */ | |
24cb81a6 | 4211 | sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 4212 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
4213 | case SCTP_CID_ACTION_SKIP: |
4214 | /* Skip the chunk. */ | |
4215 | return SCTP_DISPOSITION_DISCARD; | |
1da177e4 LT |
4216 | case SCTP_CID_ACTION_SKIP_ERR: |
4217 | /* Generate an ERROR chunk as response. */ | |
4218 | hdr = unk_chunk->chunk_hdr; | |
4219 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
4220 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
6383cfb3 VY |
4221 | WORD_ROUND(ntohs(hdr->length)), |
4222 | 0); | |
1da177e4 LT |
4223 | if (err_chunk) { |
4224 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
4225 | SCTP_CHUNK(err_chunk)); | |
4226 | } | |
4227 | /* Skip the chunk. */ | |
4228 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
4229 | default: |
4230 | break; | |
4231 | } | |
4232 | ||
4233 | return SCTP_DISPOSITION_DISCARD; | |
4234 | } | |
4235 | ||
4236 | /* | |
4237 | * Discard the chunk. | |
4238 | * | |
4239 | * Section: 0.2, 5.2.3, 5.2.5, 5.2.6, 6.0, 8.4.6, 8.5.1c, 9.2 | |
4240 | * [Too numerous to mention...] | |
4241 | * Verification Tag: No verification needed. | |
4242 | * Inputs | |
4243 | * (endpoint, asoc, chunk) | |
4244 | * | |
4245 | * Outputs | |
4246 | * (asoc, reply_msg, msg_up, timers, counters) | |
4247 | * | |
4248 | * The return value is the disposition of the chunk. | |
4249 | */ | |
24cb81a6 EB |
4250 | sctp_disposition_t sctp_sf_discard_chunk(struct net *net, |
4251 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
4252 | const struct sctp_association *asoc, |
4253 | const sctp_subtype_t type, | |
4254 | void *arg, | |
4255 | sctp_cmd_seq_t *commands) | |
4256 | { | |
ece25dfa VY |
4257 | struct sctp_chunk *chunk = arg; |
4258 | ||
4259 | /* Make sure that the chunk has a valid length. | |
4260 | * Since we don't know the chunk type, we use a general | |
4261 | * chunkhdr structure to make a comparison. | |
4262 | */ | |
4263 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 4264 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa VY |
4265 | commands); |
4266 | ||
bb33381d DB |
4267 | pr_debug("%s: chunk:%d is discarded\n", __func__, type.chunk); |
4268 | ||
1da177e4 LT |
4269 | return SCTP_DISPOSITION_DISCARD; |
4270 | } | |
4271 | ||
4272 | /* | |
4273 | * Discard the whole packet. | |
4274 | * | |
4275 | * Section: 8.4 2) | |
4276 | * | |
4277 | * 2) If the OOTB packet contains an ABORT chunk, the receiver MUST | |
4278 | * silently discard the OOTB packet and take no further action. | |
1da177e4 LT |
4279 | * |
4280 | * Verification Tag: No verification necessary | |
4281 | * | |
4282 | * Inputs | |
4283 | * (endpoint, asoc, chunk) | |
4284 | * | |
4285 | * Outputs | |
4286 | * (asoc, reply_msg, msg_up, timers, counters) | |
4287 | * | |
4288 | * The return value is the disposition of the chunk. | |
4289 | */ | |
24cb81a6 EB |
4290 | sctp_disposition_t sctp_sf_pdiscard(struct net *net, |
4291 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
4292 | const struct sctp_association *asoc, |
4293 | const sctp_subtype_t type, | |
4294 | void *arg, | |
4295 | sctp_cmd_seq_t *commands) | |
4296 | { | |
24cb81a6 | 4297 | SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_DISCARDS); |
1da177e4 LT |
4298 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
4299 | ||
4300 | return SCTP_DISPOSITION_CONSUME; | |
4301 | } | |
4302 | ||
4303 | ||
4304 | /* | |
4305 | * The other end is violating protocol. | |
4306 | * | |
4307 | * Section: Not specified | |
4308 | * Verification Tag: Not specified | |
4309 | * Inputs | |
4310 | * (endpoint, asoc, chunk) | |
4311 | * | |
4312 | * Outputs | |
4313 | * (asoc, reply_msg, msg_up, timers, counters) | |
4314 | * | |
4315 | * We simply tag the chunk as a violation. The state machine will log | |
4316 | * the violation and continue. | |
4317 | */ | |
24cb81a6 EB |
4318 | sctp_disposition_t sctp_sf_violation(struct net *net, |
4319 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
4320 | const struct sctp_association *asoc, |
4321 | const sctp_subtype_t type, | |
4322 | void *arg, | |
4323 | sctp_cmd_seq_t *commands) | |
4324 | { | |
ece25dfa VY |
4325 | struct sctp_chunk *chunk = arg; |
4326 | ||
4327 | /* Make sure that the chunk has a valid length. */ | |
4328 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
24cb81a6 | 4329 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa VY |
4330 | commands); |
4331 | ||
1da177e4 LT |
4332 | return SCTP_DISPOSITION_VIOLATION; |
4333 | } | |
4334 | ||
1da177e4 | 4335 | /* |
aecedeab | 4336 | * Common function to handle a protocol violation. |
1da177e4 | 4337 | */ |
aecedeab | 4338 | static sctp_disposition_t sctp_sf_abort_violation( |
24cb81a6 | 4339 | struct net *net, |
ece25dfa | 4340 | const struct sctp_endpoint *ep, |
1da177e4 | 4341 | const struct sctp_association *asoc, |
1da177e4 | 4342 | void *arg, |
aecedeab WY |
4343 | sctp_cmd_seq_t *commands, |
4344 | const __u8 *payload, | |
4345 | const size_t paylen) | |
1da177e4 | 4346 | { |
ece25dfa | 4347 | struct sctp_packet *packet = NULL; |
1da177e4 LT |
4348 | struct sctp_chunk *chunk = arg; |
4349 | struct sctp_chunk *abort = NULL; | |
1da177e4 | 4350 | |
bbd0d598 VY |
4351 | /* SCTP-AUTH, Section 6.3: |
4352 | * It should be noted that if the receiver wants to tear | |
4353 | * down an association in an authenticated way only, the | |
4354 | * handling of malformed packets should not result in | |
4355 | * tearing down the association. | |
4356 | * | |
4357 | * This means that if we only want to abort associations | |
4358 | * in an authenticated way (i.e AUTH+ABORT), then we | |
25985edc | 4359 | * can't destroy this association just because the packet |
bbd0d598 VY |
4360 | * was malformed. |
4361 | */ | |
4362 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) | |
4363 | goto discard; | |
4364 | ||
9abed245 JJ |
4365 | /* Make the abort chunk. */ |
4366 | abort = sctp_make_abort_violation(asoc, chunk, payload, paylen); | |
4367 | if (!abort) | |
4368 | goto nomem; | |
4369 | ||
ece25dfa | 4370 | if (asoc) { |
f4ad85ca GJ |
4371 | /* Treat INIT-ACK as a special case during COOKIE-WAIT. */ |
4372 | if (chunk->chunk_hdr->type == SCTP_CID_INIT_ACK && | |
4373 | !asoc->peer.i.init_tag) { | |
4374 | sctp_initack_chunk_t *initack; | |
4375 | ||
4376 | initack = (sctp_initack_chunk_t *)chunk->chunk_hdr; | |
4377 | if (!sctp_chunk_length_valid(chunk, | |
4378 | sizeof(sctp_initack_chunk_t))) | |
4379 | abort->chunk_hdr->flags |= SCTP_CHUNK_FLAG_T; | |
4380 | else { | |
4381 | unsigned int inittag; | |
4382 | ||
4383 | inittag = ntohl(initack->init_hdr.init_tag); | |
4384 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_INITTAG, | |
4385 | SCTP_U32(inittag)); | |
4386 | } | |
4387 | } | |
4388 | ||
ece25dfa | 4389 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
b01a2407 | 4390 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 | 4391 | |
ece25dfa VY |
4392 | if (asoc->state <= SCTP_STATE_COOKIE_ECHOED) { |
4393 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4394 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4395 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4396 | SCTP_ERROR(ECONNREFUSED)); | |
4397 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
4398 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
4399 | } else { | |
4400 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4401 | SCTP_ERROR(ECONNABORTED)); | |
4402 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
4403 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
b01a2407 | 4404 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); |
ece25dfa | 4405 | } |
1da177e4 | 4406 | } else { |
2ce95503 | 4407 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
ece25dfa VY |
4408 | |
4409 | if (!packet) | |
4410 | goto nomem_pkt; | |
4411 | ||
4412 | if (sctp_test_T_bit(abort)) | |
4413 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
4414 | ||
4415 | abort->skb->sk = ep->base.sk; | |
4416 | ||
4417 | sctp_packet_append_chunk(packet, abort); | |
4418 | ||
4419 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
4420 | SCTP_PACKET(packet)); | |
4421 | ||
b01a2407 | 4422 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
4423 | } |
4424 | ||
b01a2407 | 4425 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
d808ad9a | 4426 | |
56eb82bb | 4427 | discard: |
24cb81a6 | 4428 | sctp_sf_pdiscard(net, ep, asoc, SCTP_ST_CHUNK(0), arg, commands); |
1da177e4 LT |
4429 | return SCTP_DISPOSITION_ABORT; |
4430 | ||
ece25dfa VY |
4431 | nomem_pkt: |
4432 | sctp_chunk_free(abort); | |
1da177e4 LT |
4433 | nomem: |
4434 | return SCTP_DISPOSITION_NOMEM; | |
4435 | } | |
4436 | ||
aecedeab WY |
4437 | /* |
4438 | * Handle a protocol violation when the chunk length is invalid. | |
025dfdaf | 4439 | * "Invalid" length is identified as smaller than the minimal length a |
aecedeab | 4440 | * given chunk can be. For example, a SACK chunk has invalid length |
025dfdaf | 4441 | * if its length is set to be smaller than the size of sctp_sack_chunk_t. |
aecedeab WY |
4442 | * |
4443 | * We inform the other end by sending an ABORT with a Protocol Violation | |
4444 | * error code. | |
4445 | * | |
4446 | * Section: Not specified | |
4447 | * Verification Tag: Nothing to do | |
4448 | * Inputs | |
4449 | * (endpoint, asoc, chunk) | |
4450 | * | |
4451 | * Outputs | |
4452 | * (reply_msg, msg_up, counters) | |
4453 | * | |
4454 | * Generate an ABORT chunk and terminate the association. | |
4455 | */ | |
4456 | static sctp_disposition_t sctp_sf_violation_chunklen( | |
24cb81a6 | 4457 | struct net *net, |
aecedeab WY |
4458 | const struct sctp_endpoint *ep, |
4459 | const struct sctp_association *asoc, | |
4460 | const sctp_subtype_t type, | |
4461 | void *arg, | |
4462 | sctp_cmd_seq_t *commands) | |
4463 | { | |
cb3f837b | 4464 | static const char err_str[] = "The following chunk had invalid length:"; |
aecedeab | 4465 | |
24cb81a6 | 4466 | return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str, |
aecedeab WY |
4467 | sizeof(err_str)); |
4468 | } | |
4469 | ||
6f4c618d WY |
4470 | /* |
4471 | * Handle a protocol violation when the parameter length is invalid. | |
33c7cfdb SW |
4472 | * If the length is smaller than the minimum length of a given parameter, |
4473 | * or accumulated length in multi parameters exceeds the end of the chunk, | |
4474 | * the length is considered as invalid. | |
6f4c618d WY |
4475 | */ |
4476 | static sctp_disposition_t sctp_sf_violation_paramlen( | |
24cb81a6 | 4477 | struct net *net, |
6f4c618d WY |
4478 | const struct sctp_endpoint *ep, |
4479 | const struct sctp_association *asoc, | |
4480 | const sctp_subtype_t type, | |
ba016670 WY |
4481 | void *arg, void *ext, |
4482 | sctp_cmd_seq_t *commands) | |
4483 | { | |
4484 | struct sctp_chunk *chunk = arg; | |
4485 | struct sctp_paramhdr *param = ext; | |
4486 | struct sctp_chunk *abort = NULL; | |
6f4c618d | 4487 | |
ba016670 WY |
4488 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) |
4489 | goto discard; | |
4490 | ||
4491 | /* Make the abort chunk. */ | |
4492 | abort = sctp_make_violation_paramlen(asoc, chunk, param); | |
4493 | if (!abort) | |
4494 | goto nomem; | |
4495 | ||
4496 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); | |
b01a2407 | 4497 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
ba016670 WY |
4498 | |
4499 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4500 | SCTP_ERROR(ECONNABORTED)); | |
4501 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
4502 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
b01a2407 EB |
4503 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); |
4504 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); | |
ba016670 WY |
4505 | |
4506 | discard: | |
24cb81a6 | 4507 | sctp_sf_pdiscard(net, ep, asoc, SCTP_ST_CHUNK(0), arg, commands); |
ba016670 WY |
4508 | return SCTP_DISPOSITION_ABORT; |
4509 | nomem: | |
4510 | return SCTP_DISPOSITION_NOMEM; | |
6f4c618d WY |
4511 | } |
4512 | ||
aecedeab WY |
4513 | /* Handle a protocol violation when the peer trying to advance the |
4514 | * cumulative tsn ack to a point beyond the max tsn currently sent. | |
4515 | * | |
4516 | * We inform the other end by sending an ABORT with a Protocol Violation | |
4517 | * error code. | |
4518 | */ | |
4519 | static sctp_disposition_t sctp_sf_violation_ctsn( | |
24cb81a6 | 4520 | struct net *net, |
aecedeab WY |
4521 | const struct sctp_endpoint *ep, |
4522 | const struct sctp_association *asoc, | |
4523 | const sctp_subtype_t type, | |
4524 | void *arg, | |
4525 | sctp_cmd_seq_t *commands) | |
4526 | { | |
cb3f837b | 4527 | static const char err_str[] = "The cumulative tsn ack beyond the max tsn currently sent:"; |
aecedeab | 4528 | |
24cb81a6 | 4529 | return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str, |
aecedeab WY |
4530 | sizeof(err_str)); |
4531 | } | |
4532 | ||
ece25dfa | 4533 | /* Handle protocol violation of an invalid chunk bundling. For example, |
25985edc | 4534 | * when we have an association and we receive bundled INIT-ACK, or |
ece25dfa | 4535 | * SHUDOWN-COMPLETE, our peer is clearly violationg the "MUST NOT bundle" |
25985edc | 4536 | * statement from the specs. Additionally, there might be an attacker |
ece25dfa VY |
4537 | * on the path and we may not want to continue this communication. |
4538 | */ | |
4539 | static sctp_disposition_t sctp_sf_violation_chunk( | |
24cb81a6 | 4540 | struct net *net, |
ece25dfa VY |
4541 | const struct sctp_endpoint *ep, |
4542 | const struct sctp_association *asoc, | |
4543 | const sctp_subtype_t type, | |
4544 | void *arg, | |
4545 | sctp_cmd_seq_t *commands) | |
4546 | { | |
cb3f837b | 4547 | static const char err_str[] = "The following chunk violates protocol:"; |
ece25dfa VY |
4548 | |
4549 | if (!asoc) | |
24cb81a6 | 4550 | return sctp_sf_violation(net, ep, asoc, type, arg, commands); |
ece25dfa | 4551 | |
24cb81a6 | 4552 | return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str, |
ece25dfa VY |
4553 | sizeof(err_str)); |
4554 | } | |
1da177e4 LT |
4555 | /*************************************************************************** |
4556 | * These are the state functions for handling primitive (Section 10) events. | |
4557 | ***************************************************************************/ | |
4558 | /* | |
4559 | * sctp_sf_do_prm_asoc | |
4560 | * | |
4561 | * Section: 10.1 ULP-to-SCTP | |
4562 | * B) Associate | |
4563 | * | |
4564 | * Format: ASSOCIATE(local SCTP instance name, destination transport addr, | |
4565 | * outbound stream count) | |
4566 | * -> association id [,destination transport addr list] [,outbound stream | |
4567 | * count] | |
4568 | * | |
4569 | * This primitive allows the upper layer to initiate an association to a | |
4570 | * specific peer endpoint. | |
4571 | * | |
4572 | * The peer endpoint shall be specified by one of the transport addresses | |
4573 | * which defines the endpoint (see Section 1.4). If the local SCTP | |
4574 | * instance has not been initialized, the ASSOCIATE is considered an | |
4575 | * error. | |
4576 | * [This is not relevant for the kernel implementation since we do all | |
4577 | * initialization at boot time. It we hadn't initialized we wouldn't | |
4578 | * get anywhere near this code.] | |
4579 | * | |
4580 | * An association id, which is a local handle to the SCTP association, | |
4581 | * will be returned on successful establishment of the association. If | |
4582 | * SCTP is not able to open an SCTP association with the peer endpoint, | |
4583 | * an error is returned. | |
4584 | * [In the kernel implementation, the struct sctp_association needs to | |
4585 | * be created BEFORE causing this primitive to run.] | |
4586 | * | |
4587 | * Other association parameters may be returned, including the | |
4588 | * complete destination transport addresses of the peer as well as the | |
4589 | * outbound stream count of the local endpoint. One of the transport | |
4590 | * address from the returned destination addresses will be selected by | |
4591 | * the local endpoint as default primary path for sending SCTP packets | |
4592 | * to this peer. The returned "destination transport addr list" can | |
4593 | * be used by the ULP to change the default primary path or to force | |
4594 | * sending a packet to a specific transport address. [All of this | |
4595 | * stuff happens when the INIT ACK arrives. This is a NON-BLOCKING | |
4596 | * function.] | |
4597 | * | |
4598 | * Mandatory attributes: | |
4599 | * | |
4600 | * o local SCTP instance name - obtained from the INITIALIZE operation. | |
4601 | * [This is the argument asoc.] | |
4602 | * o destination transport addr - specified as one of the transport | |
4603 | * addresses of the peer endpoint with which the association is to be | |
4604 | * established. | |
4605 | * [This is asoc->peer.active_path.] | |
4606 | * o outbound stream count - the number of outbound streams the ULP | |
4607 | * would like to open towards this peer endpoint. | |
4608 | * [BUG: This is not currently implemented.] | |
4609 | * Optional attributes: | |
4610 | * | |
4611 | * None. | |
4612 | * | |
4613 | * The return value is a disposition. | |
4614 | */ | |
24cb81a6 EB |
4615 | sctp_disposition_t sctp_sf_do_prm_asoc(struct net *net, |
4616 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
4617 | const struct sctp_association *asoc, |
4618 | const sctp_subtype_t type, | |
4619 | void *arg, | |
4620 | sctp_cmd_seq_t *commands) | |
4621 | { | |
4622 | struct sctp_chunk *repl; | |
26ac8e5f | 4623 | struct sctp_association *my_asoc; |
1da177e4 LT |
4624 | |
4625 | /* The comment below says that we enter COOKIE-WAIT AFTER | |
4626 | * sending the INIT, but that doesn't actually work in our | |
4627 | * implementation... | |
4628 | */ | |
4629 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4630 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
4631 | ||
4632 | /* RFC 2960 5.1 Normal Establishment of an Association | |
4633 | * | |
4634 | * A) "A" first sends an INIT chunk to "Z". In the INIT, "A" | |
4635 | * must provide its Verification Tag (Tag_A) in the Initiate | |
4636 | * Tag field. Tag_A SHOULD be a random number in the range of | |
4637 | * 1 to 4294967295 (see 5.3.1 for Tag value selection). ... | |
4638 | */ | |
4639 | ||
4640 | repl = sctp_make_init(asoc, &asoc->base.bind_addr, GFP_ATOMIC, 0); | |
4641 | if (!repl) | |
4642 | goto nomem; | |
4643 | ||
405426f6 DB |
4644 | /* Choose transport for INIT. */ |
4645 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
4646 | SCTP_CHUNK(repl)); | |
4647 | ||
1da177e4 LT |
4648 | /* Cast away the const modifier, as we want to just |
4649 | * rerun it through as a sideffect. | |
4650 | */ | |
ab38fb04 VY |
4651 | my_asoc = (struct sctp_association *)asoc; |
4652 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(my_asoc)); | |
1da177e4 LT |
4653 | |
4654 | /* After sending the INIT, "A" starts the T1-init timer and | |
4655 | * enters the COOKIE-WAIT state. | |
4656 | */ | |
4657 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4658 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4659 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
4660 | return SCTP_DISPOSITION_CONSUME; | |
4661 | ||
4662 | nomem: | |
4663 | return SCTP_DISPOSITION_NOMEM; | |
4664 | } | |
4665 | ||
4666 | /* | |
4667 | * Process the SEND primitive. | |
4668 | * | |
4669 | * Section: 10.1 ULP-to-SCTP | |
4670 | * E) Send | |
4671 | * | |
4672 | * Format: SEND(association id, buffer address, byte count [,context] | |
4673 | * [,stream id] [,life time] [,destination transport address] | |
4674 | * [,unorder flag] [,no-bundle flag] [,payload protocol-id] ) | |
4675 | * -> result | |
4676 | * | |
4677 | * This is the main method to send user data via SCTP. | |
4678 | * | |
4679 | * Mandatory attributes: | |
4680 | * | |
4681 | * o association id - local handle to the SCTP association | |
4682 | * | |
4683 | * o buffer address - the location where the user message to be | |
4684 | * transmitted is stored; | |
4685 | * | |
4686 | * o byte count - The size of the user data in number of bytes; | |
4687 | * | |
4688 | * Optional attributes: | |
4689 | * | |
4690 | * o context - an optional 32 bit integer that will be carried in the | |
4691 | * sending failure notification to the ULP if the transportation of | |
4692 | * this User Message fails. | |
4693 | * | |
4694 | * o stream id - to indicate which stream to send the data on. If not | |
4695 | * specified, stream 0 will be used. | |
4696 | * | |
4697 | * o life time - specifies the life time of the user data. The user data | |
4698 | * will not be sent by SCTP after the life time expires. This | |
4699 | * parameter can be used to avoid efforts to transmit stale | |
4700 | * user messages. SCTP notifies the ULP if the data cannot be | |
4701 | * initiated to transport (i.e. sent to the destination via SCTP's | |
4702 | * send primitive) within the life time variable. However, the | |
4703 | * user data will be transmitted if SCTP has attempted to transmit a | |
4704 | * chunk before the life time expired. | |
4705 | * | |
4706 | * o destination transport address - specified as one of the destination | |
4707 | * transport addresses of the peer endpoint to which this packet | |
4708 | * should be sent. Whenever possible, SCTP should use this destination | |
4709 | * transport address for sending the packets, instead of the current | |
4710 | * primary path. | |
4711 | * | |
4712 | * o unorder flag - this flag, if present, indicates that the user | |
4713 | * would like the data delivered in an unordered fashion to the peer | |
4714 | * (i.e., the U flag is set to 1 on all DATA chunks carrying this | |
4715 | * message). | |
4716 | * | |
4717 | * o no-bundle flag - instructs SCTP not to bundle this user data with | |
4718 | * other outbound DATA chunks. SCTP MAY still bundle even when | |
4719 | * this flag is present, when faced with network congestion. | |
4720 | * | |
4721 | * o payload protocol-id - A 32 bit unsigned integer that is to be | |
4722 | * passed to the peer indicating the type of payload protocol data | |
4723 | * being transmitted. This value is passed as opaque data by SCTP. | |
4724 | * | |
4725 | * The return value is the disposition. | |
4726 | */ | |
24cb81a6 EB |
4727 | sctp_disposition_t sctp_sf_do_prm_send(struct net *net, |
4728 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
4729 | const struct sctp_association *asoc, |
4730 | const sctp_subtype_t type, | |
4731 | void *arg, | |
4732 | sctp_cmd_seq_t *commands) | |
4733 | { | |
9c5c62be | 4734 | struct sctp_datamsg *msg = arg; |
1da177e4 | 4735 | |
9c5c62be | 4736 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_MSG, SCTP_DATAMSG(msg)); |
1da177e4 LT |
4737 | return SCTP_DISPOSITION_CONSUME; |
4738 | } | |
4739 | ||
4740 | /* | |
4741 | * Process the SHUTDOWN primitive. | |
4742 | * | |
4743 | * Section: 10.1: | |
4744 | * C) Shutdown | |
4745 | * | |
4746 | * Format: SHUTDOWN(association id) | |
4747 | * -> result | |
4748 | * | |
4749 | * Gracefully closes an association. Any locally queued user data | |
4750 | * will be delivered to the peer. The association will be terminated only | |
4751 | * after the peer acknowledges all the SCTP packets sent. A success code | |
4752 | * will be returned on successful termination of the association. If | |
4753 | * attempting to terminate the association results in a failure, an error | |
4754 | * code shall be returned. | |
4755 | * | |
4756 | * Mandatory attributes: | |
4757 | * | |
4758 | * o association id - local handle to the SCTP association | |
4759 | * | |
4760 | * Optional attributes: | |
4761 | * | |
4762 | * None. | |
4763 | * | |
4764 | * The return value is the disposition. | |
4765 | */ | |
4766 | sctp_disposition_t sctp_sf_do_9_2_prm_shutdown( | |
24cb81a6 | 4767 | struct net *net, |
1da177e4 LT |
4768 | const struct sctp_endpoint *ep, |
4769 | const struct sctp_association *asoc, | |
4770 | const sctp_subtype_t type, | |
4771 | void *arg, | |
4772 | sctp_cmd_seq_t *commands) | |
4773 | { | |
4774 | int disposition; | |
4775 | ||
4776 | /* From 9.2 Shutdown of an Association | |
4777 | * Upon receipt of the SHUTDOWN primitive from its upper | |
4778 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
4779 | * remains there until all outstanding data has been | |
4780 | * acknowledged by its peer. The endpoint accepts no new data | |
4781 | * from its upper layer, but retransmits data to the far end | |
4782 | * if necessary to fill gaps. | |
4783 | */ | |
4784 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4785 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
4786 | ||
1da177e4 LT |
4787 | disposition = SCTP_DISPOSITION_CONSUME; |
4788 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
24cb81a6 | 4789 | disposition = sctp_sf_do_9_2_start_shutdown(net, ep, asoc, type, |
1da177e4 LT |
4790 | arg, commands); |
4791 | } | |
4792 | return disposition; | |
4793 | } | |
4794 | ||
4795 | /* | |
4796 | * Process the ABORT primitive. | |
4797 | * | |
4798 | * Section: 10.1: | |
4799 | * C) Abort | |
4800 | * | |
4801 | * Format: Abort(association id [, cause code]) | |
4802 | * -> result | |
4803 | * | |
4804 | * Ungracefully closes an association. Any locally queued user data | |
4805 | * will be discarded and an ABORT chunk is sent to the peer. A success code | |
4806 | * will be returned on successful abortion of the association. If | |
4807 | * attempting to abort the association results in a failure, an error | |
4808 | * code shall be returned. | |
4809 | * | |
4810 | * Mandatory attributes: | |
4811 | * | |
4812 | * o association id - local handle to the SCTP association | |
4813 | * | |
4814 | * Optional attributes: | |
4815 | * | |
4816 | * o cause code - reason of the abort to be passed to the peer | |
4817 | * | |
4818 | * None. | |
4819 | * | |
4820 | * The return value is the disposition. | |
4821 | */ | |
4822 | sctp_disposition_t sctp_sf_do_9_1_prm_abort( | |
24cb81a6 | 4823 | struct net *net, |
1da177e4 LT |
4824 | const struct sctp_endpoint *ep, |
4825 | const struct sctp_association *asoc, | |
4826 | const sctp_subtype_t type, | |
4827 | void *arg, | |
4828 | sctp_cmd_seq_t *commands) | |
4829 | { | |
4830 | /* From 9.1 Abort of an Association | |
4831 | * Upon receipt of the ABORT primitive from its upper | |
4832 | * layer, the endpoint enters CLOSED state and | |
4833 | * discard all outstanding data has been | |
4834 | * acknowledged by its peer. The endpoint accepts no new data | |
4835 | * from its upper layer, but retransmits data to the far end | |
4836 | * if necessary to fill gaps. | |
4837 | */ | |
c164a9ba | 4838 | struct sctp_chunk *abort = arg; |
1da177e4 LT |
4839 | sctp_disposition_t retval; |
4840 | ||
4841 | retval = SCTP_DISPOSITION_CONSUME; | |
4842 | ||
c164a9ba | 4843 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
1da177e4 LT |
4844 | |
4845 | /* Even if we can't send the ABORT due to low memory delete the | |
4846 | * TCB. This is a departure from our typical NOMEM handling. | |
4847 | */ | |
4848 | ||
8de8c873 SS |
4849 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4850 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 LT |
4851 | /* Delete the established association. */ |
4852 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 4853 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 | 4854 | |
b01a2407 EB |
4855 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
4856 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
4857 | |
4858 | return retval; | |
4859 | } | |
4860 | ||
4861 | /* We tried an illegal operation on an association which is closed. */ | |
24cb81a6 EB |
4862 | sctp_disposition_t sctp_sf_error_closed(struct net *net, |
4863 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
4864 | const struct sctp_association *asoc, |
4865 | const sctp_subtype_t type, | |
4866 | void *arg, | |
4867 | sctp_cmd_seq_t *commands) | |
4868 | { | |
4869 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, SCTP_ERROR(-EINVAL)); | |
4870 | return SCTP_DISPOSITION_CONSUME; | |
4871 | } | |
4872 | ||
4873 | /* We tried an illegal operation on an association which is shutting | |
4874 | * down. | |
4875 | */ | |
24cb81a6 EB |
4876 | sctp_disposition_t sctp_sf_error_shutdown(struct net *net, |
4877 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
4878 | const struct sctp_association *asoc, |
4879 | const sctp_subtype_t type, | |
4880 | void *arg, | |
4881 | sctp_cmd_seq_t *commands) | |
4882 | { | |
4883 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, | |
4884 | SCTP_ERROR(-ESHUTDOWN)); | |
4885 | return SCTP_DISPOSITION_CONSUME; | |
4886 | } | |
4887 | ||
4888 | /* | |
4889 | * sctp_cookie_wait_prm_shutdown | |
4890 | * | |
4891 | * Section: 4 Note: 2 | |
4892 | * Verification Tag: | |
4893 | * Inputs | |
4894 | * (endpoint, asoc) | |
4895 | * | |
4896 | * The RFC does not explicitly address this issue, but is the route through the | |
4897 | * state table when someone issues a shutdown while in COOKIE_WAIT state. | |
4898 | * | |
4899 | * Outputs | |
4900 | * (timers) | |
4901 | */ | |
4902 | sctp_disposition_t sctp_sf_cookie_wait_prm_shutdown( | |
24cb81a6 | 4903 | struct net *net, |
1da177e4 LT |
4904 | const struct sctp_endpoint *ep, |
4905 | const struct sctp_association *asoc, | |
4906 | const sctp_subtype_t type, | |
4907 | void *arg, | |
4908 | sctp_cmd_seq_t *commands) | |
4909 | { | |
4910 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4911 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4912 | ||
4913 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4914 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
4915 | ||
b01a2407 | 4916 | SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS); |
1da177e4 LT |
4917 | |
4918 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
4919 | ||
4920 | return SCTP_DISPOSITION_DELETE_TCB; | |
4921 | } | |
4922 | ||
4923 | /* | |
4924 | * sctp_cookie_echoed_prm_shutdown | |
4925 | * | |
4926 | * Section: 4 Note: 2 | |
4927 | * Verification Tag: | |
4928 | * Inputs | |
4929 | * (endpoint, asoc) | |
4930 | * | |
4931 | * The RFC does not explcitly address this issue, but is the route through the | |
4932 | * state table when someone issues a shutdown while in COOKIE_ECHOED state. | |
4933 | * | |
4934 | * Outputs | |
4935 | * (timers) | |
4936 | */ | |
4937 | sctp_disposition_t sctp_sf_cookie_echoed_prm_shutdown( | |
24cb81a6 | 4938 | struct net *net, |
1da177e4 LT |
4939 | const struct sctp_endpoint *ep, |
4940 | const struct sctp_association *asoc, | |
4941 | const sctp_subtype_t type, | |
4942 | void *arg, sctp_cmd_seq_t *commands) | |
4943 | { | |
4944 | /* There is a single T1 timer, so we should be able to use | |
4945 | * common function with the COOKIE-WAIT state. | |
4946 | */ | |
24cb81a6 | 4947 | return sctp_sf_cookie_wait_prm_shutdown(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
4948 | } |
4949 | ||
4950 | /* | |
4951 | * sctp_sf_cookie_wait_prm_abort | |
4952 | * | |
4953 | * Section: 4 Note: 2 | |
4954 | * Verification Tag: | |
4955 | * Inputs | |
4956 | * (endpoint, asoc) | |
4957 | * | |
4958 | * The RFC does not explicitly address this issue, but is the route through the | |
4959 | * state table when someone issues an abort while in COOKIE_WAIT state. | |
4960 | * | |
4961 | * Outputs | |
4962 | * (timers) | |
4963 | */ | |
4964 | sctp_disposition_t sctp_sf_cookie_wait_prm_abort( | |
24cb81a6 | 4965 | struct net *net, |
1da177e4 LT |
4966 | const struct sctp_endpoint *ep, |
4967 | const struct sctp_association *asoc, | |
4968 | const sctp_subtype_t type, | |
4969 | void *arg, | |
4970 | sctp_cmd_seq_t *commands) | |
4971 | { | |
c164a9ba | 4972 | struct sctp_chunk *abort = arg; |
1da177e4 LT |
4973 | sctp_disposition_t retval; |
4974 | ||
4975 | /* Stop T1-init timer */ | |
4976 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4977 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4978 | retval = SCTP_DISPOSITION_CONSUME; | |
4979 | ||
c164a9ba | 4980 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
1da177e4 LT |
4981 | |
4982 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4983 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
4984 | ||
b01a2407 | 4985 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
1da177e4 LT |
4986 | |
4987 | /* Even if we can't send the ABORT due to low memory delete the | |
4988 | * TCB. This is a departure from our typical NOMEM handling. | |
4989 | */ | |
4990 | ||
8de8c873 SS |
4991 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4992 | SCTP_ERROR(ECONNREFUSED)); | |
1da177e4 LT |
4993 | /* Delete the established association. */ |
4994 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 4995 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 LT |
4996 | |
4997 | return retval; | |
4998 | } | |
4999 | ||
5000 | /* | |
5001 | * sctp_sf_cookie_echoed_prm_abort | |
5002 | * | |
5003 | * Section: 4 Note: 3 | |
5004 | * Verification Tag: | |
5005 | * Inputs | |
5006 | * (endpoint, asoc) | |
5007 | * | |
5008 | * The RFC does not explcitly address this issue, but is the route through the | |
5009 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
5010 | * | |
5011 | * Outputs | |
5012 | * (timers) | |
5013 | */ | |
5014 | sctp_disposition_t sctp_sf_cookie_echoed_prm_abort( | |
24cb81a6 | 5015 | struct net *net, |
1da177e4 LT |
5016 | const struct sctp_endpoint *ep, |
5017 | const struct sctp_association *asoc, | |
5018 | const sctp_subtype_t type, | |
5019 | void *arg, | |
5020 | sctp_cmd_seq_t *commands) | |
5021 | { | |
5022 | /* There is a single T1 timer, so we should be able to use | |
5023 | * common function with the COOKIE-WAIT state. | |
5024 | */ | |
24cb81a6 | 5025 | return sctp_sf_cookie_wait_prm_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5026 | } |
5027 | ||
5028 | /* | |
5029 | * sctp_sf_shutdown_pending_prm_abort | |
5030 | * | |
5031 | * Inputs | |
5032 | * (endpoint, asoc) | |
5033 | * | |
5034 | * The RFC does not explicitly address this issue, but is the route through the | |
5035 | * state table when someone issues an abort while in SHUTDOWN-PENDING state. | |
5036 | * | |
5037 | * Outputs | |
5038 | * (timers) | |
5039 | */ | |
5040 | sctp_disposition_t sctp_sf_shutdown_pending_prm_abort( | |
24cb81a6 | 5041 | struct net *net, |
1da177e4 LT |
5042 | const struct sctp_endpoint *ep, |
5043 | const struct sctp_association *asoc, | |
5044 | const sctp_subtype_t type, | |
5045 | void *arg, | |
5046 | sctp_cmd_seq_t *commands) | |
5047 | { | |
5048 | /* Stop the T5-shutdown guard timer. */ | |
5049 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5050 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
5051 | ||
24cb81a6 | 5052 | return sctp_sf_do_9_1_prm_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5053 | } |
5054 | ||
5055 | /* | |
5056 | * sctp_sf_shutdown_sent_prm_abort | |
5057 | * | |
5058 | * Inputs | |
5059 | * (endpoint, asoc) | |
5060 | * | |
5061 | * The RFC does not explicitly address this issue, but is the route through the | |
5062 | * state table when someone issues an abort while in SHUTDOWN-SENT state. | |
5063 | * | |
5064 | * Outputs | |
5065 | * (timers) | |
5066 | */ | |
5067 | sctp_disposition_t sctp_sf_shutdown_sent_prm_abort( | |
24cb81a6 | 5068 | struct net *net, |
1da177e4 LT |
5069 | const struct sctp_endpoint *ep, |
5070 | const struct sctp_association *asoc, | |
5071 | const sctp_subtype_t type, | |
5072 | void *arg, | |
5073 | sctp_cmd_seq_t *commands) | |
5074 | { | |
5075 | /* Stop the T2-shutdown timer. */ | |
5076 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5077 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5078 | ||
5079 | /* Stop the T5-shutdown guard timer. */ | |
5080 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5081 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
5082 | ||
24cb81a6 | 5083 | return sctp_sf_do_9_1_prm_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5084 | } |
5085 | ||
5086 | /* | |
5087 | * sctp_sf_cookie_echoed_prm_abort | |
5088 | * | |
5089 | * Inputs | |
5090 | * (endpoint, asoc) | |
5091 | * | |
5092 | * The RFC does not explcitly address this issue, but is the route through the | |
5093 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
5094 | * | |
5095 | * Outputs | |
5096 | * (timers) | |
5097 | */ | |
5098 | sctp_disposition_t sctp_sf_shutdown_ack_sent_prm_abort( | |
24cb81a6 | 5099 | struct net *net, |
1da177e4 LT |
5100 | const struct sctp_endpoint *ep, |
5101 | const struct sctp_association *asoc, | |
5102 | const sctp_subtype_t type, | |
5103 | void *arg, | |
5104 | sctp_cmd_seq_t *commands) | |
5105 | { | |
5106 | /* The same T2 timer, so we should be able to use | |
5107 | * common function with the SHUTDOWN-SENT state. | |
5108 | */ | |
24cb81a6 | 5109 | return sctp_sf_shutdown_sent_prm_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5110 | } |
5111 | ||
5112 | /* | |
5113 | * Process the REQUESTHEARTBEAT primitive | |
5114 | * | |
5115 | * 10.1 ULP-to-SCTP | |
5116 | * J) Request Heartbeat | |
5117 | * | |
5118 | * Format: REQUESTHEARTBEAT(association id, destination transport address) | |
5119 | * | |
5120 | * -> result | |
5121 | * | |
5122 | * Instructs the local endpoint to perform a HeartBeat on the specified | |
5123 | * destination transport address of the given association. The returned | |
5124 | * result should indicate whether the transmission of the HEARTBEAT | |
5125 | * chunk to the destination address is successful. | |
5126 | * | |
5127 | * Mandatory attributes: | |
5128 | * | |
5129 | * o association id - local handle to the SCTP association | |
5130 | * | |
5131 | * o destination transport address - the transport address of the | |
5132 | * association on which a heartbeat should be issued. | |
5133 | */ | |
5134 | sctp_disposition_t sctp_sf_do_prm_requestheartbeat( | |
24cb81a6 | 5135 | struct net *net, |
1da177e4 LT |
5136 | const struct sctp_endpoint *ep, |
5137 | const struct sctp_association *asoc, | |
5138 | const sctp_subtype_t type, | |
5139 | void *arg, | |
5140 | sctp_cmd_seq_t *commands) | |
5141 | { | |
fb78525a VY |
5142 | if (SCTP_DISPOSITION_NOMEM == sctp_sf_heartbeat(ep, asoc, type, |
5143 | (struct sctp_transport *)arg, commands)) | |
5144 | return SCTP_DISPOSITION_NOMEM; | |
5145 | ||
5146 | /* | |
5147 | * RFC 2960 (bis), section 8.3 | |
5148 | * | |
5149 | * D) Request an on-demand HEARTBEAT on a specific destination | |
5150 | * transport address of a given association. | |
5151 | * | |
5152 | * The endpoint should increment the respective error counter of | |
5153 | * the destination transport address each time a HEARTBEAT is sent | |
5154 | * to that address and not acknowledged within one RTO. | |
5155 | * | |
5156 | */ | |
7e99013a | 5157 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_HB_SENT, |
fb78525a VY |
5158 | SCTP_TRANSPORT(arg)); |
5159 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
5160 | } |
5161 | ||
5162 | /* | |
5163 | * ADDIP Section 4.1 ASCONF Chunk Procedures | |
5164 | * When an endpoint has an ASCONF signaled change to be sent to the | |
5165 | * remote endpoint it should do A1 to A9 | |
5166 | */ | |
24cb81a6 EB |
5167 | sctp_disposition_t sctp_sf_do_prm_asconf(struct net *net, |
5168 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5169 | const struct sctp_association *asoc, |
5170 | const sctp_subtype_t type, | |
5171 | void *arg, | |
5172 | sctp_cmd_seq_t *commands) | |
5173 | { | |
5174 | struct sctp_chunk *chunk = arg; | |
5175 | ||
5176 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
5177 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
5178 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
5179 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk)); | |
5180 | return SCTP_DISPOSITION_CONSUME; | |
5181 | } | |
5182 | ||
5183 | /* | |
5184 | * Ignore the primitive event | |
5185 | * | |
5186 | * The return value is the disposition of the primitive. | |
5187 | */ | |
5188 | sctp_disposition_t sctp_sf_ignore_primitive( | |
24cb81a6 | 5189 | struct net *net, |
1da177e4 LT |
5190 | const struct sctp_endpoint *ep, |
5191 | const struct sctp_association *asoc, | |
5192 | const sctp_subtype_t type, | |
5193 | void *arg, | |
5194 | sctp_cmd_seq_t *commands) | |
5195 | { | |
bb33381d DB |
5196 | pr_debug("%s: primitive type:%d is ignored\n", __func__, |
5197 | type.primitive); | |
5198 | ||
1da177e4 LT |
5199 | return SCTP_DISPOSITION_DISCARD; |
5200 | } | |
5201 | ||
5202 | /*************************************************************************** | |
5203 | * These are the state functions for the OTHER events. | |
5204 | ***************************************************************************/ | |
5205 | ||
e1cdd553 WY |
5206 | /* |
5207 | * When the SCTP stack has no more user data to send or retransmit, this | |
5208 | * notification is given to the user. Also, at the time when a user app | |
5209 | * subscribes to this event, if there is no data to be sent or | |
5210 | * retransmit, the stack will immediately send up this notification. | |
5211 | */ | |
5212 | sctp_disposition_t sctp_sf_do_no_pending_tsn( | |
24cb81a6 | 5213 | struct net *net, |
e1cdd553 WY |
5214 | const struct sctp_endpoint *ep, |
5215 | const struct sctp_association *asoc, | |
5216 | const sctp_subtype_t type, | |
5217 | void *arg, | |
5218 | sctp_cmd_seq_t *commands) | |
5219 | { | |
5220 | struct sctp_ulpevent *event; | |
5221 | ||
5222 | event = sctp_ulpevent_make_sender_dry_event(asoc, GFP_ATOMIC); | |
5223 | if (!event) | |
5224 | return SCTP_DISPOSITION_NOMEM; | |
5225 | ||
5226 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(event)); | |
5227 | ||
5228 | return SCTP_DISPOSITION_CONSUME; | |
5229 | } | |
5230 | ||
1da177e4 LT |
5231 | /* |
5232 | * Start the shutdown negotiation. | |
5233 | * | |
5234 | * From Section 9.2: | |
5235 | * Once all its outstanding data has been acknowledged, the endpoint | |
5236 | * shall send a SHUTDOWN chunk to its peer including in the Cumulative | |
5237 | * TSN Ack field the last sequential TSN it has received from the peer. | |
5238 | * It shall then start the T2-shutdown timer and enter the SHUTDOWN-SENT | |
5239 | * state. If the timer expires, the endpoint must re-send the SHUTDOWN | |
5240 | * with the updated last sequential TSN received from its peer. | |
5241 | * | |
5242 | * The return value is the disposition. | |
5243 | */ | |
5244 | sctp_disposition_t sctp_sf_do_9_2_start_shutdown( | |
24cb81a6 | 5245 | struct net *net, |
1da177e4 LT |
5246 | const struct sctp_endpoint *ep, |
5247 | const struct sctp_association *asoc, | |
5248 | const sctp_subtype_t type, | |
5249 | void *arg, | |
5250 | sctp_cmd_seq_t *commands) | |
5251 | { | |
5252 | struct sctp_chunk *reply; | |
5253 | ||
5254 | /* Once all its outstanding data has been acknowledged, the | |
5255 | * endpoint shall send a SHUTDOWN chunk to its peer including | |
5256 | * in the Cumulative TSN Ack field the last sequential TSN it | |
5257 | * has received from the peer. | |
5258 | */ | |
5259 | reply = sctp_make_shutdown(asoc, NULL); | |
5260 | if (!reply) | |
5261 | goto nomem; | |
5262 | ||
5263 | /* Set the transport for the SHUTDOWN chunk and the timeout for the | |
5264 | * T2-shutdown timer. | |
5265 | */ | |
5266 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5267 | ||
5268 | /* It shall then start the T2-shutdown timer */ | |
5269 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
5270 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5271 | ||
536428a9 WY |
5272 | /* RFC 4960 Section 9.2 |
5273 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
5274 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
5275 | */ | |
f8d96052 | 5276 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, |
536428a9 WY |
5277 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); |
5278 | ||
9f70f46b | 5279 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) |
1da177e4 LT |
5280 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, |
5281 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
5282 | ||
5283 | /* and enter the SHUTDOWN-SENT state. */ | |
5284 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5285 | SCTP_STATE(SCTP_STATE_SHUTDOWN_SENT)); | |
5286 | ||
5287 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
5288 | * | |
5289 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 5290 | * or SHUTDOWN-ACK. |
1da177e4 LT |
5291 | */ |
5292 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
5293 | ||
5294 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5295 | ||
5296 | return SCTP_DISPOSITION_CONSUME; | |
5297 | ||
5298 | nomem: | |
5299 | return SCTP_DISPOSITION_NOMEM; | |
5300 | } | |
5301 | ||
5302 | /* | |
5303 | * Generate a SHUTDOWN ACK now that everything is SACK'd. | |
5304 | * | |
5305 | * From Section 9.2: | |
5306 | * | |
5307 | * If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
5308 | * shall send a SHUTDOWN ACK and start a T2-shutdown timer of its own, | |
5309 | * entering the SHUTDOWN-ACK-SENT state. If the timer expires, the | |
5310 | * endpoint must re-send the SHUTDOWN ACK. | |
5311 | * | |
5312 | * The return value is the disposition. | |
5313 | */ | |
5314 | sctp_disposition_t sctp_sf_do_9_2_shutdown_ack( | |
24cb81a6 | 5315 | struct net *net, |
1da177e4 LT |
5316 | const struct sctp_endpoint *ep, |
5317 | const struct sctp_association *asoc, | |
5318 | const sctp_subtype_t type, | |
5319 | void *arg, | |
5320 | sctp_cmd_seq_t *commands) | |
5321 | { | |
5322 | struct sctp_chunk *chunk = (struct sctp_chunk *) arg; | |
5323 | struct sctp_chunk *reply; | |
5324 | ||
5325 | /* There are 2 ways of getting here: | |
5326 | * 1) called in response to a SHUTDOWN chunk | |
5327 | * 2) called when SCTP_EVENT_NO_PENDING_TSN event is issued. | |
5328 | * | |
5329 | * For the case (2), the arg parameter is set to NULL. We need | |
5330 | * to check that we have a chunk before accessing it's fields. | |
5331 | */ | |
5332 | if (chunk) { | |
5333 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 5334 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5335 | |
5336 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
5337 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_shutdown_chunk_t))) | |
24cb81a6 | 5338 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
5339 | commands); |
5340 | } | |
5341 | ||
5342 | /* If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
5343 | * shall send a SHUTDOWN ACK ... | |
5344 | */ | |
5345 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
5346 | if (!reply) | |
5347 | goto nomem; | |
5348 | ||
5349 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
5350 | * the T2-shutdown timer. | |
5351 | */ | |
5352 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5353 | ||
5354 | /* and start/restart a T2-shutdown timer of its own, */ | |
5355 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5356 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5357 | ||
9f70f46b | 5358 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) |
1da177e4 LT |
5359 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, |
5360 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
5361 | ||
5362 | /* Enter the SHUTDOWN-ACK-SENT state. */ | |
5363 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5364 | SCTP_STATE(SCTP_STATE_SHUTDOWN_ACK_SENT)); | |
5365 | ||
5366 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
5367 | * | |
5368 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 5369 | * or SHUTDOWN-ACK. |
1da177e4 LT |
5370 | */ |
5371 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
5372 | ||
5373 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5374 | ||
5375 | return SCTP_DISPOSITION_CONSUME; | |
5376 | ||
5377 | nomem: | |
5378 | return SCTP_DISPOSITION_NOMEM; | |
5379 | } | |
5380 | ||
5381 | /* | |
5382 | * Ignore the event defined as other | |
5383 | * | |
5384 | * The return value is the disposition of the event. | |
5385 | */ | |
24cb81a6 EB |
5386 | sctp_disposition_t sctp_sf_ignore_other(struct net *net, |
5387 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5388 | const struct sctp_association *asoc, |
5389 | const sctp_subtype_t type, | |
5390 | void *arg, | |
5391 | sctp_cmd_seq_t *commands) | |
5392 | { | |
bb33381d DB |
5393 | pr_debug("%s: the event other type:%d is ignored\n", |
5394 | __func__, type.other); | |
5395 | ||
1da177e4 LT |
5396 | return SCTP_DISPOSITION_DISCARD; |
5397 | } | |
5398 | ||
5399 | /************************************************************ | |
5400 | * These are the state functions for handling timeout events. | |
5401 | ************************************************************/ | |
5402 | ||
5403 | /* | |
5404 | * RTX Timeout | |
5405 | * | |
5406 | * Section: 6.3.3 Handle T3-rtx Expiration | |
5407 | * | |
5408 | * Whenever the retransmission timer T3-rtx expires for a destination | |
5409 | * address, do the following: | |
5410 | * [See below] | |
5411 | * | |
5412 | * The return value is the disposition of the chunk. | |
5413 | */ | |
24cb81a6 EB |
5414 | sctp_disposition_t sctp_sf_do_6_3_3_rtx(struct net *net, |
5415 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5416 | const struct sctp_association *asoc, |
5417 | const sctp_subtype_t type, | |
5418 | void *arg, | |
5419 | sctp_cmd_seq_t *commands) | |
5420 | { | |
5421 | struct sctp_transport *transport = arg; | |
5422 | ||
b01a2407 | 5423 | SCTP_INC_STATS(net, SCTP_MIB_T3_RTX_EXPIREDS); |
ac0b0462 | 5424 | |
1da177e4 | 5425 | if (asoc->overall_error_count >= asoc->max_retrans) { |
f8d96052 TG |
5426 | if (asoc->state == SCTP_STATE_SHUTDOWN_PENDING) { |
5427 | /* | |
5428 | * We are here likely because the receiver had its rwnd | |
5429 | * closed for a while and we have not been able to | |
5430 | * transmit the locally queued data within the maximum | |
5431 | * retransmission attempts limit. Start the T5 | |
5432 | * shutdown guard timer to give the receiver one last | |
5433 | * chance and some additional time to recover before | |
5434 | * aborting. | |
5435 | */ | |
5436 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START_ONCE, | |
5437 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
5438 | } else { | |
5439 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
5440 | SCTP_ERROR(ETIMEDOUT)); | |
5441 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ | |
5442 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5443 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); | |
b01a2407 EB |
5444 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
5445 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
f8d96052 TG |
5446 | return SCTP_DISPOSITION_DELETE_TCB; |
5447 | } | |
1da177e4 LT |
5448 | } |
5449 | ||
5450 | /* E1) For the destination address for which the timer | |
5451 | * expires, adjust its ssthresh with rules defined in Section | |
5452 | * 7.2.3 and set the cwnd <- MTU. | |
5453 | */ | |
5454 | ||
5455 | /* E2) For the destination address for which the timer | |
5456 | * expires, set RTO <- RTO * 2 ("back off the timer"). The | |
5457 | * maximum value discussed in rule C7 above (RTO.max) may be | |
5458 | * used to provide an upper bound to this doubling operation. | |
5459 | */ | |
5460 | ||
5461 | /* E3) Determine how many of the earliest (i.e., lowest TSN) | |
5462 | * outstanding DATA chunks for the address for which the | |
5463 | * T3-rtx has expired will fit into a single packet, subject | |
5464 | * to the MTU constraint for the path corresponding to the | |
5465 | * destination transport address to which the retransmission | |
5466 | * is being sent (this may be different from the address for | |
5467 | * which the timer expires [see Section 6.4]). Call this | |
5468 | * value K. Bundle and retransmit those K DATA chunks in a | |
5469 | * single packet to the destination endpoint. | |
5470 | * | |
5471 | * Note: Any DATA chunks that were sent to the address for | |
5472 | * which the T3-rtx timer expired but did not fit in one MTU | |
5473 | * (rule E3 above), should be marked for retransmission and | |
5474 | * sent as soon as cwnd allows (normally when a SACK arrives). | |
5475 | */ | |
5476 | ||
1da177e4 LT |
5477 | /* Do some failure management (Section 8.2). */ |
5478 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport)); | |
5479 | ||
1845a579 VY |
5480 | /* NB: Rules E4 and F1 are implicit in R1. */ |
5481 | sctp_add_cmd_sf(commands, SCTP_CMD_RETRAN, SCTP_TRANSPORT(transport)); | |
5482 | ||
1da177e4 LT |
5483 | return SCTP_DISPOSITION_CONSUME; |
5484 | } | |
5485 | ||
5486 | /* | |
5487 | * Generate delayed SACK on timeout | |
5488 | * | |
5489 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
5490 | * | |
5491 | * The guidelines on delayed acknowledgement algorithm specified in | |
5492 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
5493 | * acknowledgement SHOULD be generated for at least every second packet | |
5494 | * (not every second DATA chunk) received, and SHOULD be generated | |
5495 | * within 200 ms of the arrival of any unacknowledged DATA chunk. In | |
5496 | * some situations it may be beneficial for an SCTP transmitter to be | |
5497 | * more conservative than the algorithms detailed in this document | |
5498 | * allow. However, an SCTP transmitter MUST NOT be more aggressive than | |
5499 | * the following algorithms allow. | |
5500 | */ | |
24cb81a6 EB |
5501 | sctp_disposition_t sctp_sf_do_6_2_sack(struct net *net, |
5502 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5503 | const struct sctp_association *asoc, |
5504 | const sctp_subtype_t type, | |
5505 | void *arg, | |
5506 | sctp_cmd_seq_t *commands) | |
5507 | { | |
b01a2407 | 5508 | SCTP_INC_STATS(net, SCTP_MIB_DELAY_SACK_EXPIREDS); |
1da177e4 LT |
5509 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); |
5510 | return SCTP_DISPOSITION_CONSUME; | |
5511 | } | |
5512 | ||
5513 | /* | |
3f7a87d2 | 5514 | * sctp_sf_t1_init_timer_expire |
1da177e4 LT |
5515 | * |
5516 | * Section: 4 Note: 2 | |
5517 | * Verification Tag: | |
5518 | * Inputs | |
5519 | * (endpoint, asoc) | |
5520 | * | |
5521 | * RFC 2960 Section 4 Notes | |
5522 | * 2) If the T1-init timer expires, the endpoint MUST retransmit INIT | |
5523 | * and re-start the T1-init timer without changing state. This MUST | |
5524 | * be repeated up to 'Max.Init.Retransmits' times. After that, the | |
5525 | * endpoint MUST abort the initialization process and report the | |
5526 | * error to SCTP user. | |
5527 | * | |
3f7a87d2 FF |
5528 | * Outputs |
5529 | * (timers, events) | |
5530 | * | |
5531 | */ | |
24cb81a6 EB |
5532 | sctp_disposition_t sctp_sf_t1_init_timer_expire(struct net *net, |
5533 | const struct sctp_endpoint *ep, | |
3f7a87d2 FF |
5534 | const struct sctp_association *asoc, |
5535 | const sctp_subtype_t type, | |
5536 | void *arg, | |
5537 | sctp_cmd_seq_t *commands) | |
5538 | { | |
5539 | struct sctp_chunk *repl = NULL; | |
5540 | struct sctp_bind_addr *bp; | |
5541 | int attempts = asoc->init_err_counter + 1; | |
5542 | ||
bb33381d DB |
5543 | pr_debug("%s: timer T1 expired (INIT)\n", __func__); |
5544 | ||
b01a2407 | 5545 | SCTP_INC_STATS(net, SCTP_MIB_T1_INIT_EXPIREDS); |
3f7a87d2 | 5546 | |
81845c21 | 5547 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 FF |
5548 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; |
5549 | repl = sctp_make_init(asoc, bp, GFP_ATOMIC, 0); | |
5550 | if (!repl) | |
5551 | return SCTP_DISPOSITION_NOMEM; | |
5552 | ||
5553 | /* Choose transport for INIT. */ | |
5554 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
5555 | SCTP_CHUNK(repl)); | |
5556 | ||
5557 | /* Issue a sideeffect to do the needed accounting. */ | |
5558 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_RESTART, | |
5559 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
5560 | ||
5561 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
5562 | } else { | |
bb33381d DB |
5563 | pr_debug("%s: giving up on INIT, attempts:%d " |
5564 | "max_init_attempts:%d\n", __func__, attempts, | |
5565 | asoc->max_init_attempts); | |
5566 | ||
8de8c873 SS |
5567 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5568 | SCTP_ERROR(ETIMEDOUT)); | |
3f7a87d2 | 5569 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 5570 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
3f7a87d2 FF |
5571 | return SCTP_DISPOSITION_DELETE_TCB; |
5572 | } | |
5573 | ||
5574 | return SCTP_DISPOSITION_CONSUME; | |
5575 | } | |
5576 | ||
5577 | /* | |
5578 | * sctp_sf_t1_cookie_timer_expire | |
5579 | * | |
5580 | * Section: 4 Note: 2 | |
5581 | * Verification Tag: | |
5582 | * Inputs | |
5583 | * (endpoint, asoc) | |
5584 | * | |
5585 | * RFC 2960 Section 4 Notes | |
5586 | * 3) If the T1-cookie timer expires, the endpoint MUST retransmit | |
1da177e4 LT |
5587 | * COOKIE ECHO and re-start the T1-cookie timer without changing |
5588 | * state. This MUST be repeated up to 'Max.Init.Retransmits' times. | |
5589 | * After that, the endpoint MUST abort the initialization process and | |
5590 | * report the error to SCTP user. | |
5591 | * | |
5592 | * Outputs | |
5593 | * (timers, events) | |
5594 | * | |
5595 | */ | |
24cb81a6 EB |
5596 | sctp_disposition_t sctp_sf_t1_cookie_timer_expire(struct net *net, |
5597 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5598 | const struct sctp_association *asoc, |
5599 | const sctp_subtype_t type, | |
5600 | void *arg, | |
5601 | sctp_cmd_seq_t *commands) | |
5602 | { | |
3f7a87d2 FF |
5603 | struct sctp_chunk *repl = NULL; |
5604 | int attempts = asoc->init_err_counter + 1; | |
1da177e4 | 5605 | |
bb33381d DB |
5606 | pr_debug("%s: timer T1 expired (COOKIE-ECHO)\n", __func__); |
5607 | ||
b01a2407 | 5608 | SCTP_INC_STATS(net, SCTP_MIB_T1_COOKIE_EXPIREDS); |
1da177e4 | 5609 | |
81845c21 | 5610 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 | 5611 | repl = sctp_make_cookie_echo(asoc, NULL); |
1da177e4 | 5612 | if (!repl) |
3f7a87d2 | 5613 | return SCTP_DISPOSITION_NOMEM; |
1da177e4 | 5614 | |
96cd0d3d VY |
5615 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, |
5616 | SCTP_CHUNK(repl)); | |
1da177e4 | 5617 | /* Issue a sideeffect to do the needed accounting. */ |
3f7a87d2 FF |
5618 | sctp_add_cmd_sf(commands, SCTP_CMD_COOKIEECHO_RESTART, |
5619 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
5620 | ||
1da177e4 LT |
5621 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
5622 | } else { | |
8de8c873 SS |
5623 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5624 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5625 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 5626 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5627 | return SCTP_DISPOSITION_DELETE_TCB; |
5628 | } | |
5629 | ||
5630 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
5631 | } |
5632 | ||
5633 | /* RFC2960 9.2 If the timer expires, the endpoint must re-send the SHUTDOWN | |
5634 | * with the updated last sequential TSN received from its peer. | |
5635 | * | |
5636 | * An endpoint should limit the number of retransmissions of the | |
5637 | * SHUTDOWN chunk to the protocol parameter 'Association.Max.Retrans'. | |
5638 | * If this threshold is exceeded the endpoint should destroy the TCB and | |
5639 | * MUST report the peer endpoint unreachable to the upper layer (and | |
5640 | * thus the association enters the CLOSED state). The reception of any | |
5641 | * packet from its peer (i.e. as the peer sends all of its queued DATA | |
5642 | * chunks) should clear the endpoint's retransmission count and restart | |
5643 | * the T2-Shutdown timer, giving its peer ample opportunity to transmit | |
5644 | * all of its queued DATA chunks that have not yet been sent. | |
5645 | */ | |
24cb81a6 EB |
5646 | sctp_disposition_t sctp_sf_t2_timer_expire(struct net *net, |
5647 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5648 | const struct sctp_association *asoc, |
5649 | const sctp_subtype_t type, | |
5650 | void *arg, | |
5651 | sctp_cmd_seq_t *commands) | |
5652 | { | |
5653 | struct sctp_chunk *reply = NULL; | |
5654 | ||
bb33381d DB |
5655 | pr_debug("%s: timer T2 expired\n", __func__); |
5656 | ||
b01a2407 | 5657 | SCTP_INC_STATS(net, SCTP_MIB_T2_SHUTDOWN_EXPIREDS); |
ac0b0462 | 5658 | |
58fbbed4 NH |
5659 | ((struct sctp_association *)asoc)->shutdown_retries++; |
5660 | ||
1da177e4 | 5661 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
5662 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5663 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
5664 | /* Note: CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
5665 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 5666 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
b01a2407 EB |
5667 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
5668 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
5669 | return SCTP_DISPOSITION_DELETE_TCB; |
5670 | } | |
5671 | ||
5672 | switch (asoc->state) { | |
5673 | case SCTP_STATE_SHUTDOWN_SENT: | |
5674 | reply = sctp_make_shutdown(asoc, NULL); | |
5675 | break; | |
5676 | ||
5677 | case SCTP_STATE_SHUTDOWN_ACK_SENT: | |
5678 | reply = sctp_make_shutdown_ack(asoc, NULL); | |
5679 | break; | |
5680 | ||
5681 | default: | |
5682 | BUG(); | |
5683 | break; | |
3ff50b79 | 5684 | } |
1da177e4 LT |
5685 | |
5686 | if (!reply) | |
5687 | goto nomem; | |
5688 | ||
6345b199 WY |
5689 | /* Do some failure management (Section 8.2). |
5690 | * If we remove the transport an SHUTDOWN was last sent to, don't | |
5691 | * do failure management. | |
5692 | */ | |
5693 | if (asoc->shutdown_last_sent_to) | |
5694 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, | |
5695 | SCTP_TRANSPORT(asoc->shutdown_last_sent_to)); | |
1da177e4 LT |
5696 | |
5697 | /* Set the transport for the SHUTDOWN/ACK chunk and the timeout for | |
5698 | * the T2-shutdown timer. | |
5699 | */ | |
5700 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5701 | ||
5702 | /* Restart the T2-shutdown timer. */ | |
5703 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5704 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5705 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5706 | return SCTP_DISPOSITION_CONSUME; | |
5707 | ||
5708 | nomem: | |
5709 | return SCTP_DISPOSITION_NOMEM; | |
5710 | } | |
5711 | ||
5712 | /* | |
5713 | * ADDIP Section 4.1 ASCONF CHunk Procedures | |
5714 | * If the T4 RTO timer expires the endpoint should do B1 to B5 | |
5715 | */ | |
5716 | sctp_disposition_t sctp_sf_t4_timer_expire( | |
24cb81a6 | 5717 | struct net *net, |
1da177e4 LT |
5718 | const struct sctp_endpoint *ep, |
5719 | const struct sctp_association *asoc, | |
5720 | const sctp_subtype_t type, | |
5721 | void *arg, | |
5722 | sctp_cmd_seq_t *commands) | |
5723 | { | |
5724 | struct sctp_chunk *chunk = asoc->addip_last_asconf; | |
5725 | struct sctp_transport *transport = chunk->transport; | |
5726 | ||
b01a2407 | 5727 | SCTP_INC_STATS(net, SCTP_MIB_T4_RTO_EXPIREDS); |
ac0b0462 | 5728 | |
1da177e4 LT |
5729 | /* ADDIP 4.1 B1) Increment the error counters and perform path failure |
5730 | * detection on the appropriate destination address as defined in | |
5731 | * RFC2960 [5] section 8.1 and 8.2. | |
5732 | */ | |
10a43cea WY |
5733 | if (transport) |
5734 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, | |
5735 | SCTP_TRANSPORT(transport)); | |
1da177e4 LT |
5736 | |
5737 | /* Reconfig T4 timer and transport. */ | |
5738 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
5739 | ||
5740 | /* ADDIP 4.1 B2) Increment the association error counters and perform | |
5741 | * endpoint failure detection on the association as defined in | |
5742 | * RFC2960 [5] section 8.1 and 8.2. | |
5743 | * association error counter is incremented in SCTP_CMD_STRIKE. | |
5744 | */ | |
5745 | if (asoc->overall_error_count >= asoc->max_retrans) { | |
5746 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5747 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
8de8c873 SS |
5748 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5749 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5750 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5751 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
b01a2407 EB |
5752 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
5753 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
5754 | return SCTP_DISPOSITION_ABORT; |
5755 | } | |
5756 | ||
5757 | /* ADDIP 4.1 B3) Back-off the destination address RTO value to which | |
5758 | * the ASCONF chunk was sent by doubling the RTO timer value. | |
5759 | * This is done in SCTP_CMD_STRIKE. | |
5760 | */ | |
5761 | ||
5762 | /* ADDIP 4.1 B4) Re-transmit the ASCONF Chunk last sent and if possible | |
5763 | * choose an alternate destination address (please refer to RFC2960 | |
5764 | * [5] section 6.4.1). An endpoint MUST NOT add new parameters to this | |
d808ad9a | 5765 | * chunk, it MUST be the same (including its serial number) as the last |
1da177e4 LT |
5766 | * ASCONF sent. |
5767 | */ | |
5768 | sctp_chunk_hold(asoc->addip_last_asconf); | |
5769 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
5770 | SCTP_CHUNK(asoc->addip_last_asconf)); | |
5771 | ||
5772 | /* ADDIP 4.1 B5) Restart the T-4 RTO timer. Note that if a different | |
5773 | * destination is selected, then the RTO used will be that of the new | |
5774 | * destination address. | |
5775 | */ | |
5776 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5777 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
5778 | ||
5779 | return SCTP_DISPOSITION_CONSUME; | |
5780 | } | |
5781 | ||
5782 | /* sctpimpguide-05 Section 2.12.2 | |
5783 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
5784 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
5785 | * At the expiration of this timer the sender SHOULD abort the association | |
5786 | * by sending an ABORT chunk. | |
5787 | */ | |
24cb81a6 EB |
5788 | sctp_disposition_t sctp_sf_t5_timer_expire(struct net *net, |
5789 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5790 | const struct sctp_association *asoc, |
5791 | const sctp_subtype_t type, | |
5792 | void *arg, | |
5793 | sctp_cmd_seq_t *commands) | |
5794 | { | |
5795 | struct sctp_chunk *reply = NULL; | |
5796 | ||
bb33381d DB |
5797 | pr_debug("%s: timer T5 expired\n", __func__); |
5798 | ||
b01a2407 | 5799 | SCTP_INC_STATS(net, SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS); |
1da177e4 LT |
5800 | |
5801 | reply = sctp_make_abort(asoc, NULL, 0); | |
5802 | if (!reply) | |
5803 | goto nomem; | |
5804 | ||
5805 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
8de8c873 SS |
5806 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5807 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5808 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5809 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 | 5810 | |
b01a2407 EB |
5811 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
5812 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
a1080a8b | 5813 | |
1da177e4 LT |
5814 | return SCTP_DISPOSITION_DELETE_TCB; |
5815 | nomem: | |
5816 | return SCTP_DISPOSITION_NOMEM; | |
5817 | } | |
5818 | ||
5819 | /* Handle expiration of AUTOCLOSE timer. When the autoclose timer expires, | |
5820 | * the association is automatically closed by starting the shutdown process. | |
5821 | * The work that needs to be done is same as when SHUTDOWN is initiated by | |
5822 | * the user. So this routine looks same as sctp_sf_do_9_2_prm_shutdown(). | |
5823 | */ | |
5824 | sctp_disposition_t sctp_sf_autoclose_timer_expire( | |
24cb81a6 | 5825 | struct net *net, |
1da177e4 LT |
5826 | const struct sctp_endpoint *ep, |
5827 | const struct sctp_association *asoc, | |
5828 | const sctp_subtype_t type, | |
5829 | void *arg, | |
5830 | sctp_cmd_seq_t *commands) | |
5831 | { | |
5832 | int disposition; | |
5833 | ||
b01a2407 | 5834 | SCTP_INC_STATS(net, SCTP_MIB_AUTOCLOSE_EXPIREDS); |
ac0b0462 | 5835 | |
1da177e4 LT |
5836 | /* From 9.2 Shutdown of an Association |
5837 | * Upon receipt of the SHUTDOWN primitive from its upper | |
5838 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
5839 | * remains there until all outstanding data has been | |
5840 | * acknowledged by its peer. The endpoint accepts no new data | |
5841 | * from its upper layer, but retransmits data to the far end | |
5842 | * if necessary to fill gaps. | |
5843 | */ | |
5844 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5845 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
5846 | ||
1da177e4 LT |
5847 | disposition = SCTP_DISPOSITION_CONSUME; |
5848 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
24cb81a6 | 5849 | disposition = sctp_sf_do_9_2_start_shutdown(net, ep, asoc, type, |
1da177e4 LT |
5850 | arg, commands); |
5851 | } | |
5852 | return disposition; | |
5853 | } | |
5854 | ||
5855 | /***************************************************************************** | |
5856 | * These are sa state functions which could apply to all types of events. | |
5857 | ****************************************************************************/ | |
5858 | ||
5859 | /* | |
5860 | * This table entry is not implemented. | |
5861 | * | |
5862 | * Inputs | |
5863 | * (endpoint, asoc, chunk) | |
5864 | * | |
5865 | * The return value is the disposition of the chunk. | |
5866 | */ | |
24cb81a6 EB |
5867 | sctp_disposition_t sctp_sf_not_impl(struct net *net, |
5868 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5869 | const struct sctp_association *asoc, |
5870 | const sctp_subtype_t type, | |
5871 | void *arg, | |
5872 | sctp_cmd_seq_t *commands) | |
5873 | { | |
5874 | return SCTP_DISPOSITION_NOT_IMPL; | |
5875 | } | |
5876 | ||
5877 | /* | |
5878 | * This table entry represents a bug. | |
5879 | * | |
5880 | * Inputs | |
5881 | * (endpoint, asoc, chunk) | |
5882 | * | |
5883 | * The return value is the disposition of the chunk. | |
5884 | */ | |
24cb81a6 EB |
5885 | sctp_disposition_t sctp_sf_bug(struct net *net, |
5886 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5887 | const struct sctp_association *asoc, |
5888 | const sctp_subtype_t type, | |
5889 | void *arg, | |
5890 | sctp_cmd_seq_t *commands) | |
5891 | { | |
5892 | return SCTP_DISPOSITION_BUG; | |
5893 | } | |
5894 | ||
5895 | /* | |
5896 | * This table entry represents the firing of a timer in the wrong state. | |
5897 | * Since timer deletion cannot be guaranteed a timer 'may' end up firing | |
5898 | * when the association is in the wrong state. This event should | |
5899 | * be ignored, so as to prevent any rearming of the timer. | |
5900 | * | |
5901 | * Inputs | |
5902 | * (endpoint, asoc, chunk) | |
5903 | * | |
5904 | * The return value is the disposition of the chunk. | |
5905 | */ | |
24cb81a6 EB |
5906 | sctp_disposition_t sctp_sf_timer_ignore(struct net *net, |
5907 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5908 | const struct sctp_association *asoc, |
5909 | const sctp_subtype_t type, | |
5910 | void *arg, | |
5911 | sctp_cmd_seq_t *commands) | |
5912 | { | |
bb33381d DB |
5913 | pr_debug("%s: timer %d ignored\n", __func__, type.chunk); |
5914 | ||
1da177e4 LT |
5915 | return SCTP_DISPOSITION_CONSUME; |
5916 | } | |
5917 | ||
5918 | /******************************************************************** | |
5919 | * 2nd Level Abstractions | |
5920 | ********************************************************************/ | |
5921 | ||
5922 | /* Pull the SACK chunk based on the SACK header. */ | |
5923 | static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk) | |
5924 | { | |
5925 | struct sctp_sackhdr *sack; | |
5926 | unsigned int len; | |
5927 | __u16 num_blocks; | |
5928 | __u16 num_dup_tsns; | |
5929 | ||
5930 | /* Protect ourselves from reading too far into | |
5931 | * the skb from a bogus sender. | |
5932 | */ | |
5933 | sack = (struct sctp_sackhdr *) chunk->skb->data; | |
5934 | ||
5935 | num_blocks = ntohs(sack->num_gap_ack_blocks); | |
5936 | num_dup_tsns = ntohs(sack->num_dup_tsns); | |
5937 | len = sizeof(struct sctp_sackhdr); | |
5938 | len += (num_blocks + num_dup_tsns) * sizeof(__u32); | |
5939 | if (len > chunk->skb->len) | |
5940 | return NULL; | |
5941 | ||
5942 | skb_pull(chunk->skb, len); | |
5943 | ||
5944 | return sack; | |
5945 | } | |
5946 | ||
5947 | /* Create an ABORT packet to be sent as a response, with the specified | |
5948 | * error causes. | |
5949 | */ | |
24cb81a6 EB |
5950 | static struct sctp_packet *sctp_abort_pkt_new(struct net *net, |
5951 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
5952 | const struct sctp_association *asoc, |
5953 | struct sctp_chunk *chunk, | |
5954 | const void *payload, | |
5955 | size_t paylen) | |
5956 | { | |
5957 | struct sctp_packet *packet; | |
5958 | struct sctp_chunk *abort; | |
5959 | ||
2ce95503 | 5960 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
1da177e4 LT |
5961 | |
5962 | if (packet) { | |
5963 | /* Make an ABORT. | |
5964 | * The T bit will be set if the asoc is NULL. | |
5965 | */ | |
5966 | abort = sctp_make_abort(asoc, chunk, paylen); | |
5967 | if (!abort) { | |
5968 | sctp_ootb_pkt_free(packet); | |
5969 | return NULL; | |
5970 | } | |
047a2428 JF |
5971 | |
5972 | /* Reflect vtag if T-Bit is set */ | |
5973 | if (sctp_test_T_bit(abort)) | |
5974 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
5975 | ||
1da177e4 LT |
5976 | /* Add specified error causes, i.e., payload, to the |
5977 | * end of the chunk. | |
5978 | */ | |
5979 | sctp_addto_chunk(abort, paylen, payload); | |
5980 | ||
5981 | /* Set the skb to the belonging sock for accounting. */ | |
5982 | abort->skb->sk = ep->base.sk; | |
5983 | ||
5984 | sctp_packet_append_chunk(packet, abort); | |
5985 | ||
5986 | } | |
5987 | ||
5988 | return packet; | |
5989 | } | |
5990 | ||
5991 | /* Allocate a packet for responding in the OOTB conditions. */ | |
2ce95503 EB |
5992 | static struct sctp_packet *sctp_ootb_pkt_new(struct net *net, |
5993 | const struct sctp_association *asoc, | |
1da177e4 LT |
5994 | const struct sctp_chunk *chunk) |
5995 | { | |
5996 | struct sctp_packet *packet; | |
5997 | struct sctp_transport *transport; | |
5998 | __u16 sport; | |
5999 | __u16 dport; | |
6000 | __u32 vtag; | |
6001 | ||
6002 | /* Get the source and destination port from the inbound packet. */ | |
6003 | sport = ntohs(chunk->sctp_hdr->dest); | |
6004 | dport = ntohs(chunk->sctp_hdr->source); | |
6005 | ||
6006 | /* The V-tag is going to be the same as the inbound packet if no | |
6007 | * association exists, otherwise, use the peer's vtag. | |
6008 | */ | |
6009 | if (asoc) { | |
02c4e12c WY |
6010 | /* Special case the INIT-ACK as there is no peer's vtag |
6011 | * yet. | |
6012 | */ | |
cb3f837b | 6013 | switch (chunk->chunk_hdr->type) { |
02c4e12c WY |
6014 | case SCTP_CID_INIT_ACK: |
6015 | { | |
6016 | sctp_initack_chunk_t *initack; | |
6017 | ||
6018 | initack = (sctp_initack_chunk_t *)chunk->chunk_hdr; | |
6019 | vtag = ntohl(initack->init_hdr.init_tag); | |
6020 | break; | |
6021 | } | |
6022 | default: | |
6023 | vtag = asoc->peer.i.init_tag; | |
6024 | break; | |
6025 | } | |
1da177e4 LT |
6026 | } else { |
6027 | /* Special case the INIT and stale COOKIE_ECHO as there is no | |
6028 | * vtag yet. | |
6029 | */ | |
cb3f837b | 6030 | switch (chunk->chunk_hdr->type) { |
1da177e4 LT |
6031 | case SCTP_CID_INIT: |
6032 | { | |
6033 | sctp_init_chunk_t *init; | |
6034 | ||
6035 | init = (sctp_init_chunk_t *)chunk->chunk_hdr; | |
6036 | vtag = ntohl(init->init_hdr.init_tag); | |
6037 | break; | |
6038 | } | |
d808ad9a | 6039 | default: |
1da177e4 LT |
6040 | vtag = ntohl(chunk->sctp_hdr->vtag); |
6041 | break; | |
6042 | } | |
6043 | } | |
6044 | ||
6045 | /* Make a transport for the bucket, Eliza... */ | |
89bf3450 | 6046 | transport = sctp_transport_new(net, sctp_source(chunk), GFP_ATOMIC); |
1da177e4 LT |
6047 | if (!transport) |
6048 | goto nomem; | |
6049 | ||
6050 | /* Cache a route for the transport with the chunk's destination as | |
6051 | * the source address. | |
6052 | */ | |
16b0a030 | 6053 | sctp_transport_route(transport, (union sctp_addr *)&chunk->dest, |
2ce95503 | 6054 | sctp_sk(net->sctp.ctl_sock)); |
1da177e4 LT |
6055 | |
6056 | packet = sctp_packet_init(&transport->packet, transport, sport, dport); | |
6057 | packet = sctp_packet_config(packet, vtag, 0); | |
6058 | ||
6059 | return packet; | |
6060 | ||
6061 | nomem: | |
6062 | return NULL; | |
6063 | } | |
6064 | ||
6065 | /* Free the packet allocated earlier for responding in the OOTB condition. */ | |
6066 | void sctp_ootb_pkt_free(struct sctp_packet *packet) | |
6067 | { | |
6068 | sctp_transport_free(packet->transport); | |
6069 | } | |
6070 | ||
6071 | /* Send a stale cookie error when a invalid COOKIE ECHO chunk is found */ | |
24cb81a6 EB |
6072 | static void sctp_send_stale_cookie_err(struct net *net, |
6073 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
6074 | const struct sctp_association *asoc, |
6075 | const struct sctp_chunk *chunk, | |
6076 | sctp_cmd_seq_t *commands, | |
6077 | struct sctp_chunk *err_chunk) | |
6078 | { | |
6079 | struct sctp_packet *packet; | |
6080 | ||
6081 | if (err_chunk) { | |
2ce95503 | 6082 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
1da177e4 LT |
6083 | if (packet) { |
6084 | struct sctp_signed_cookie *cookie; | |
6085 | ||
6086 | /* Override the OOTB vtag from the cookie. */ | |
6087 | cookie = chunk->subh.cookie_hdr; | |
6088 | packet->vtag = cookie->c.peer_vtag; | |
d808ad9a | 6089 | |
1da177e4 LT |
6090 | /* Set the skb to the belonging sock for accounting. */ |
6091 | err_chunk->skb->sk = ep->base.sk; | |
6092 | sctp_packet_append_chunk(packet, err_chunk); | |
6093 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
6094 | SCTP_PACKET(packet)); | |
b01a2407 | 6095 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
6096 | } else |
6097 | sctp_chunk_free (err_chunk); | |
6098 | } | |
6099 | } | |
6100 | ||
6101 | ||
6102 | /* Process a data chunk */ | |
6103 | static int sctp_eat_data(const struct sctp_association *asoc, | |
6104 | struct sctp_chunk *chunk, | |
6105 | sctp_cmd_seq_t *commands) | |
6106 | { | |
6107 | sctp_datahdr_t *data_hdr; | |
6108 | struct sctp_chunk *err; | |
6109 | size_t datalen; | |
6110 | sctp_verb_t deliver; | |
6111 | int tmp; | |
6112 | __u32 tsn; | |
7c3ceb4f | 6113 | struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map; |
049b3ff5 | 6114 | struct sock *sk = asoc->base.sk; |
24cb81a6 | 6115 | struct net *net = sock_net(sk); |
f1751c57 VY |
6116 | u16 ssn; |
6117 | u16 sid; | |
6118 | u8 ordered = 0; | |
1da177e4 LT |
6119 | |
6120 | data_hdr = chunk->subh.data_hdr = (sctp_datahdr_t *)chunk->skb->data; | |
6121 | skb_pull(chunk->skb, sizeof(sctp_datahdr_t)); | |
6122 | ||
6123 | tsn = ntohl(data_hdr->tsn); | |
bb33381d | 6124 | pr_debug("%s: TSN 0x%x\n", __func__, tsn); |
1da177e4 LT |
6125 | |
6126 | /* ASSERT: Now skb->data is really the user data. */ | |
6127 | ||
6128 | /* Process ECN based congestion. | |
6129 | * | |
6130 | * Since the chunk structure is reused for all chunks within | |
6131 | * a packet, we use ecn_ce_done to track if we've already | |
6132 | * done CE processing for this packet. | |
6133 | * | |
6134 | * We need to do ECN processing even if we plan to discard the | |
6135 | * chunk later. | |
6136 | */ | |
6137 | ||
6138 | if (!chunk->ecn_ce_done) { | |
6139 | struct sctp_af *af; | |
6140 | chunk->ecn_ce_done = 1; | |
6141 | ||
6142 | af = sctp_get_af_specific( | |
eddc9ec5 | 6143 | ipver2af(ip_hdr(chunk->skb)->version)); |
1da177e4 LT |
6144 | |
6145 | if (af && af->is_ce(chunk->skb) && asoc->peer.ecn_capable) { | |
6146 | /* Do real work as sideffect. */ | |
6147 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_CE, | |
6148 | SCTP_U32(tsn)); | |
6149 | } | |
6150 | } | |
6151 | ||
6152 | tmp = sctp_tsnmap_check(&asoc->peer.tsn_map, tsn); | |
6153 | if (tmp < 0) { | |
6154 | /* The TSN is too high--silently discard the chunk and | |
6155 | * count on it getting retransmitted later. | |
6156 | */ | |
196d6759 MB |
6157 | if (chunk->asoc) |
6158 | chunk->asoc->stats.outofseqtsns++; | |
1da177e4 LT |
6159 | return SCTP_IERROR_HIGH_TSN; |
6160 | } else if (tmp > 0) { | |
6161 | /* This is a duplicate. Record it. */ | |
6162 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_DUP, SCTP_U32(tsn)); | |
6163 | return SCTP_IERROR_DUP_TSN; | |
6164 | } | |
6165 | ||
6166 | /* This is a new TSN. */ | |
6167 | ||
6168 | /* Discard if there is no room in the receive window. | |
6169 | * Actually, allow a little bit of overflow (up to a MTU). | |
6170 | */ | |
6171 | datalen = ntohs(chunk->chunk_hdr->length); | |
6172 | datalen -= sizeof(sctp_data_chunk_t); | |
6173 | ||
6174 | deliver = SCTP_CMD_CHUNK_ULP; | |
6175 | ||
6176 | /* Think about partial delivery. */ | |
6177 | if ((datalen >= asoc->rwnd) && (!asoc->ulpq.pd_mode)) { | |
6178 | ||
6179 | /* Even if we don't accept this chunk there is | |
6180 | * memory pressure. | |
6181 | */ | |
6182 | sctp_add_cmd_sf(commands, SCTP_CMD_PART_DELIVER, SCTP_NULL()); | |
6183 | } | |
6184 | ||
d808ad9a | 6185 | /* Spill over rwnd a little bit. Note: While allowed, this spill over |
1da177e4 LT |
6186 | * seems a bit troublesome in that frag_point varies based on |
6187 | * PMTU. In cases, such as loopback, this might be a rather | |
6188 | * large spill over. | |
4d93df0a | 6189 | */ |
362d5204 | 6190 | if ((!chunk->data_accepted) && (!asoc->rwnd || asoc->rwnd_over || |
4d93df0a | 6191 | (datalen > asoc->rwnd + asoc->frag_point))) { |
1da177e4 LT |
6192 | |
6193 | /* If this is the next TSN, consider reneging to make | |
6194 | * room. Note: Playing nice with a confused sender. A | |
6195 | * malicious sender can still eat up all our buffer | |
6196 | * space and in the future we may want to detect and | |
6197 | * do more drastic reneging. | |
6198 | */ | |
7c3ceb4f NH |
6199 | if (sctp_tsnmap_has_gap(map) && |
6200 | (sctp_tsnmap_get_ctsn(map) + 1) == tsn) { | |
bb33381d | 6201 | pr_debug("%s: reneging for tsn:%u\n", __func__, tsn); |
1da177e4 LT |
6202 | deliver = SCTP_CMD_RENEGE; |
6203 | } else { | |
bb33381d DB |
6204 | pr_debug("%s: discard tsn:%u len:%zu, rwnd:%d\n", |
6205 | __func__, tsn, datalen, asoc->rwnd); | |
6206 | ||
1da177e4 LT |
6207 | return SCTP_IERROR_IGNORE_TSN; |
6208 | } | |
6209 | } | |
6210 | ||
4d93df0a NH |
6211 | /* |
6212 | * Also try to renege to limit our memory usage in the event that | |
6213 | * we are under memory pressure | |
3ab224be | 6214 | * If we can't renege, don't worry about it, the sk_rmem_schedule |
4d93df0a NH |
6215 | * in sctp_ulpevent_make_rcvmsg will drop the frame if we grow our |
6216 | * memory usage too much | |
6217 | */ | |
6218 | if (*sk->sk_prot_creator->memory_pressure) { | |
6219 | if (sctp_tsnmap_has_gap(map) && | |
f7010e61 | 6220 | (sctp_tsnmap_get_ctsn(map) + 1) == tsn) { |
bb33381d DB |
6221 | pr_debug("%s: under pressure, reneging for tsn:%u\n", |
6222 | __func__, tsn); | |
4d93df0a NH |
6223 | deliver = SCTP_CMD_RENEGE; |
6224 | } | |
6225 | } | |
6226 | ||
1da177e4 LT |
6227 | /* |
6228 | * Section 3.3.10.9 No User Data (9) | |
6229 | * | |
6230 | * Cause of error | |
6231 | * --------------- | |
6232 | * No User Data: This error cause is returned to the originator of a | |
6233 | * DATA chunk if a received DATA chunk has no user data. | |
6234 | */ | |
6235 | if (unlikely(0 == datalen)) { | |
6236 | err = sctp_make_abort_no_data(asoc, chunk, tsn); | |
6237 | if (err) { | |
6238 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
6239 | SCTP_CHUNK(err)); | |
6240 | } | |
6241 | /* We are going to ABORT, so we might as well stop | |
6242 | * processing the rest of the chunks in the packet. | |
6243 | */ | |
cb3f837b | 6244 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
8de8c873 SS |
6245 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
6246 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 | 6247 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 6248 | SCTP_PERR(SCTP_ERROR_NO_DATA)); |
b01a2407 EB |
6249 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
6250 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
6251 | return SCTP_IERROR_NO_DATA; |
6252 | } | |
6253 | ||
9faa730f SS |
6254 | chunk->data_accepted = 1; |
6255 | ||
1da177e4 LT |
6256 | /* Note: Some chunks may get overcounted (if we drop) or overcounted |
6257 | * if we renege and the chunk arrives again. | |
6258 | */ | |
196d6759 | 6259 | if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) { |
b01a2407 | 6260 | SCTP_INC_STATS(net, SCTP_MIB_INUNORDERCHUNKS); |
196d6759 MB |
6261 | if (chunk->asoc) |
6262 | chunk->asoc->stats.iuodchunks++; | |
6263 | } else { | |
b01a2407 | 6264 | SCTP_INC_STATS(net, SCTP_MIB_INORDERCHUNKS); |
196d6759 MB |
6265 | if (chunk->asoc) |
6266 | chunk->asoc->stats.iodchunks++; | |
f1751c57 VY |
6267 | ordered = 1; |
6268 | } | |
1da177e4 LT |
6269 | |
6270 | /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number | |
6271 | * | |
6272 | * If an endpoint receive a DATA chunk with an invalid stream | |
6273 | * identifier, it shall acknowledge the reception of the DATA chunk | |
6274 | * following the normal procedure, immediately send an ERROR chunk | |
6275 | * with cause set to "Invalid Stream Identifier" (See Section 3.3.10) | |
6276 | * and discard the DATA chunk. | |
6277 | */ | |
f1751c57 VY |
6278 | sid = ntohs(data_hdr->stream); |
6279 | if (sid >= asoc->c.sinit_max_instreams) { | |
3888e9ef VY |
6280 | /* Mark tsn as received even though we drop it */ |
6281 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_TSN, SCTP_U32(tsn)); | |
6282 | ||
1da177e4 LT |
6283 | err = sctp_make_op_error(asoc, chunk, SCTP_ERROR_INV_STRM, |
6284 | &data_hdr->stream, | |
6383cfb3 VY |
6285 | sizeof(data_hdr->stream), |
6286 | sizeof(u16)); | |
1da177e4 LT |
6287 | if (err) |
6288 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
6289 | SCTP_CHUNK(err)); | |
6290 | return SCTP_IERROR_BAD_STREAM; | |
6291 | } | |
6292 | ||
f1751c57 VY |
6293 | /* Check to see if the SSN is possible for this TSN. |
6294 | * The biggest gap we can record is 4K wide. Since SSNs wrap | |
6295 | * at an unsigned short, there is no way that an SSN can | |
6296 | * wrap and for a valid TSN. We can simply check if the current | |
6297 | * SSN is smaller then the next expected one. If it is, it wrapped | |
6298 | * and is invalid. | |
6299 | */ | |
6300 | ssn = ntohs(data_hdr->ssn); | |
6301 | if (ordered && SSN_lt(ssn, sctp_ssn_peek(&asoc->ssnmap->in, sid))) { | |
6302 | return SCTP_IERROR_PROTO_VIOLATION; | |
6303 | } | |
6304 | ||
1da177e4 LT |
6305 | /* Send the data up to the user. Note: Schedule the |
6306 | * SCTP_CMD_CHUNK_ULP cmd before the SCTP_CMD_GEN_SACK, as the SACK | |
6307 | * chunk needs the updated rwnd. | |
6308 | */ | |
6309 | sctp_add_cmd_sf(commands, deliver, SCTP_CHUNK(chunk)); | |
6310 | ||
6311 | return SCTP_IERROR_NO_ERROR; | |
6312 | } |