Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * DECnet An implementation of the DECnet protocol suite for the LINUX | |
3 | * operating system. DECnet is implemented using the BSD Socket | |
4 | * interface as the means of communication with the user level. | |
5 | * | |
6 | * DECnet Network Services Protocol (Input) | |
7 | * | |
8 | * Author: Eduardo Marcelo Serrat <emserrat@geocities.com> | |
9 | * | |
10 | * Changes: | |
11 | * | |
12 | * Steve Whitehouse: Split into dn_nsp_in.c and dn_nsp_out.c from | |
13 | * original dn_nsp.c. | |
14 | * Steve Whitehouse: Updated to work with my new routing architecture. | |
15 | * Steve Whitehouse: Add changes from Eduardo Serrat's patches. | |
16 | * Steve Whitehouse: Put all ack handling code in a common routine. | |
17 | * Steve Whitehouse: Put other common bits into dn_nsp_rx() | |
18 | * Steve Whitehouse: More checks on skb->len to catch bogus packets | |
19 | * Fixed various race conditions and possible nasties. | |
20 | * Steve Whitehouse: Now handles returned conninit frames. | |
21 | * David S. Miller: New socket locking | |
22 | * Steve Whitehouse: Fixed lockup when socket filtering was enabled. | |
23 | * Paul Koning: Fix to push CC sockets into RUN when acks are | |
24 | * received. | |
25 | * Steve Whitehouse: | |
26 | * Patrick Caulfield: Checking conninits for correctness & sending of error | |
27 | * responses. | |
28 | * Steve Whitehouse: Added backlog congestion level return codes. | |
29 | * Patrick Caulfield: | |
30 | * Steve Whitehouse: Added flow control support (outbound) | |
31 | * Steve Whitehouse: Prepare for nonlinear skbs | |
32 | */ | |
33 | ||
34 | /****************************************************************************** | |
35 | (c) 1995-1998 E.M. Serrat emserrat@geocities.com | |
429eb0fa | 36 | |
1da177e4 LT |
37 | This program is free software; you can redistribute it and/or modify |
38 | it under the terms of the GNU General Public License as published by | |
39 | the Free Software Foundation; either version 2 of the License, or | |
40 | any later version. | |
41 | ||
42 | This program is distributed in the hope that it will be useful, | |
43 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
44 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
45 | GNU General Public License for more details. | |
46 | *******************************************************************************/ | |
47 | ||
1da177e4 LT |
48 | #include <linux/errno.h> |
49 | #include <linux/types.h> | |
50 | #include <linux/socket.h> | |
51 | #include <linux/in.h> | |
52 | #include <linux/kernel.h> | |
1da177e4 LT |
53 | #include <linux/timer.h> |
54 | #include <linux/string.h> | |
55 | #include <linux/sockios.h> | |
56 | #include <linux/net.h> | |
57 | #include <linux/netdevice.h> | |
58 | #include <linux/inet.h> | |
59 | #include <linux/route.h> | |
5a0e3ad6 | 60 | #include <linux/slab.h> |
1da177e4 | 61 | #include <net/sock.h> |
c752f073 | 62 | #include <net/tcp_states.h> |
1da177e4 LT |
63 | #include <asm/system.h> |
64 | #include <linux/fcntl.h> | |
65 | #include <linux/mm.h> | |
429eb0fa | 66 | #include <linux/termios.h> |
1da177e4 LT |
67 | #include <linux/interrupt.h> |
68 | #include <linux/proc_fs.h> | |
69 | #include <linux/stat.h> | |
70 | #include <linux/init.h> | |
71 | #include <linux/poll.h> | |
72 | #include <linux/netfilter_decnet.h> | |
73 | #include <net/neighbour.h> | |
74 | #include <net/dst.h> | |
75 | #include <net/dn.h> | |
76 | #include <net/dn_nsp.h> | |
77 | #include <net/dn_dev.h> | |
78 | #include <net/dn_route.h> | |
79 | ||
80 | extern int decnet_log_martians; | |
81 | ||
82 | static void dn_log_martian(struct sk_buff *skb, const char *msg) | |
83 | { | |
84 | if (decnet_log_martians && net_ratelimit()) { | |
85 | char *devname = skb->dev ? skb->dev->name : "???"; | |
86 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | |
c4106aa8 HH |
87 | printk(KERN_INFO "DECnet: Martian packet (%s) dev=%s src=0x%04hx dst=0x%04hx srcport=0x%04hx dstport=0x%04hx\n", |
88 | msg, devname, le16_to_cpu(cb->src), le16_to_cpu(cb->dst), | |
89 | le16_to_cpu(cb->src_port), le16_to_cpu(cb->dst_port)); | |
1da177e4 LT |
90 | } |
91 | } | |
92 | ||
93 | /* | |
94 | * For this function we've flipped the cross-subchannel bit | |
95 | * if the message is an otherdata or linkservice message. Thus | |
96 | * we can use it to work out what to update. | |
97 | */ | |
98 | static void dn_ack(struct sock *sk, struct sk_buff *skb, unsigned short ack) | |
99 | { | |
100 | struct dn_scp *scp = DN_SK(sk); | |
101 | unsigned short type = ((ack >> 12) & 0x0003); | |
102 | int wakeup = 0; | |
103 | ||
06f8fe11 JP |
104 | switch (type) { |
105 | case 0: /* ACK - Data */ | |
106 | if (dn_after(ack, scp->ackrcv_dat)) { | |
107 | scp->ackrcv_dat = ack & 0x0fff; | |
108 | wakeup |= dn_nsp_check_xmit_queue(sk, skb, | |
109 | &scp->data_xmit_queue, | |
110 | ack); | |
111 | } | |
112 | break; | |
113 | case 1: /* NAK - Data */ | |
114 | break; | |
115 | case 2: /* ACK - OtherData */ | |
116 | if (dn_after(ack, scp->ackrcv_oth)) { | |
117 | scp->ackrcv_oth = ack & 0x0fff; | |
118 | wakeup |= dn_nsp_check_xmit_queue(sk, skb, | |
119 | &scp->other_xmit_queue, | |
120 | ack); | |
121 | } | |
122 | break; | |
123 | case 3: /* NAK - OtherData */ | |
124 | break; | |
1da177e4 LT |
125 | } |
126 | ||
127 | if (wakeup && !sock_flag(sk, SOCK_DEAD)) | |
128 | sk->sk_state_change(sk); | |
129 | } | |
130 | ||
131 | /* | |
132 | * This function is a universal ack processor. | |
133 | */ | |
134 | static int dn_process_ack(struct sock *sk, struct sk_buff *skb, int oth) | |
135 | { | |
c4ea94ab | 136 | __le16 *ptr = (__le16 *)skb->data; |
1da177e4 LT |
137 | int len = 0; |
138 | unsigned short ack; | |
139 | ||
140 | if (skb->len < 2) | |
141 | return len; | |
142 | ||
c4106aa8 | 143 | if ((ack = le16_to_cpu(*ptr)) & 0x8000) { |
1da177e4 LT |
144 | skb_pull(skb, 2); |
145 | ptr++; | |
146 | len += 2; | |
147 | if ((ack & 0x4000) == 0) { | |
429eb0fa | 148 | if (oth) |
1da177e4 LT |
149 | ack ^= 0x2000; |
150 | dn_ack(sk, skb, ack); | |
151 | } | |
152 | } | |
153 | ||
154 | if (skb->len < 2) | |
155 | return len; | |
156 | ||
c4106aa8 | 157 | if ((ack = le16_to_cpu(*ptr)) & 0x8000) { |
1da177e4 LT |
158 | skb_pull(skb, 2); |
159 | len += 2; | |
160 | if ((ack & 0x4000) == 0) { | |
429eb0fa | 161 | if (oth) |
1da177e4 LT |
162 | ack ^= 0x2000; |
163 | dn_ack(sk, skb, ack); | |
164 | } | |
165 | } | |
166 | ||
167 | return len; | |
168 | } | |
169 | ||
170 | ||
171 | /** | |
172 | * dn_check_idf - Check an image data field format is correct. | |
173 | * @pptr: Pointer to pointer to image data | |
174 | * @len: Pointer to length of image data | |
175 | * @max: The maximum allowed length of the data in the image data field | |
176 | * @follow_on: Check that this many bytes exist beyond the end of the image data | |
177 | * | |
178 | * Returns: 0 if ok, -1 on error | |
179 | */ | |
180 | static inline int dn_check_idf(unsigned char **pptr, int *len, unsigned char max, unsigned char follow_on) | |
181 | { | |
182 | unsigned char *ptr = *pptr; | |
183 | unsigned char flen = *ptr++; | |
184 | ||
185 | (*len)--; | |
186 | if (flen > max) | |
187 | return -1; | |
188 | if ((flen + follow_on) > *len) | |
189 | return -1; | |
190 | ||
191 | *len -= flen; | |
192 | *pptr = ptr + flen; | |
193 | return 0; | |
194 | } | |
195 | ||
196 | /* | |
197 | * Table of reason codes to pass back to node which sent us a badly | |
198 | * formed message, plus text messages for the log. A zero entry in | |
199 | * the reason field means "don't reply" otherwise a disc init is sent with | |
200 | * the specified reason code. | |
201 | */ | |
202 | static struct { | |
203 | unsigned short reason; | |
204 | const char *text; | |
205 | } ci_err_table[] = { | |
206 | { 0, "CI: Truncated message" }, | |
207 | { NSP_REASON_ID, "CI: Destination username error" }, | |
208 | { NSP_REASON_ID, "CI: Destination username type" }, | |
209 | { NSP_REASON_US, "CI: Source username error" }, | |
210 | { 0, "CI: Truncated at menuver" }, | |
211 | { 0, "CI: Truncated before access or user data" }, | |
212 | { NSP_REASON_IO, "CI: Access data format error" }, | |
213 | { NSP_REASON_IO, "CI: User data format error" } | |
214 | }; | |
215 | ||
216 | /* | |
217 | * This function uses a slightly different lookup method | |
218 | * to find its sockets, since it searches on object name/number | |
219 | * rather than port numbers. Various tests are done to ensure that | |
220 | * the incoming data is in the correct format before it is queued to | |
221 | * a socket. | |
222 | */ | |
223 | static struct sock *dn_find_listener(struct sk_buff *skb, unsigned short *reason) | |
224 | { | |
225 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | |
226 | struct nsp_conn_init_msg *msg = (struct nsp_conn_init_msg *)skb->data; | |
227 | struct sockaddr_dn dstaddr; | |
228 | struct sockaddr_dn srcaddr; | |
229 | unsigned char type = 0; | |
230 | int dstlen; | |
231 | int srclen; | |
232 | unsigned char *ptr; | |
233 | int len; | |
234 | int err = 0; | |
235 | unsigned char menuver; | |
236 | ||
237 | memset(&dstaddr, 0, sizeof(struct sockaddr_dn)); | |
238 | memset(&srcaddr, 0, sizeof(struct sockaddr_dn)); | |
239 | ||
240 | /* | |
241 | * 1. Decode & remove message header | |
242 | */ | |
243 | cb->src_port = msg->srcaddr; | |
244 | cb->dst_port = msg->dstaddr; | |
245 | cb->services = msg->services; | |
246 | cb->info = msg->info; | |
c4106aa8 | 247 | cb->segsize = le16_to_cpu(msg->segsize); |
1da177e4 LT |
248 | |
249 | if (!pskb_may_pull(skb, sizeof(*msg))) | |
250 | goto err_out; | |
251 | ||
252 | skb_pull(skb, sizeof(*msg)); | |
253 | ||
254 | len = skb->len; | |
255 | ptr = skb->data; | |
256 | ||
257 | /* | |
258 | * 2. Check destination end username format | |
259 | */ | |
260 | dstlen = dn_username2sockaddr(ptr, len, &dstaddr, &type); | |
261 | err++; | |
262 | if (dstlen < 0) | |
263 | goto err_out; | |
264 | ||
265 | err++; | |
266 | if (type > 1) | |
267 | goto err_out; | |
268 | ||
269 | len -= dstlen; | |
270 | ptr += dstlen; | |
271 | ||
272 | /* | |
273 | * 3. Check source end username format | |
274 | */ | |
275 | srclen = dn_username2sockaddr(ptr, len, &srcaddr, &type); | |
276 | err++; | |
277 | if (srclen < 0) | |
278 | goto err_out; | |
279 | ||
280 | len -= srclen; | |
281 | ptr += srclen; | |
282 | err++; | |
283 | if (len < 1) | |
284 | goto err_out; | |
285 | ||
286 | menuver = *ptr; | |
287 | ptr++; | |
288 | len--; | |
289 | ||
290 | /* | |
291 | * 4. Check that optional data actually exists if menuver says it does | |
292 | */ | |
293 | err++; | |
294 | if ((menuver & (DN_MENUVER_ACC | DN_MENUVER_USR)) && (len < 1)) | |
295 | goto err_out; | |
296 | ||
297 | /* | |
298 | * 5. Check optional access data format | |
299 | */ | |
300 | err++; | |
301 | if (menuver & DN_MENUVER_ACC) { | |
302 | if (dn_check_idf(&ptr, &len, 39, 1)) | |
303 | goto err_out; | |
304 | if (dn_check_idf(&ptr, &len, 39, 1)) | |
305 | goto err_out; | |
306 | if (dn_check_idf(&ptr, &len, 39, (menuver & DN_MENUVER_USR) ? 1 : 0)) | |
307 | goto err_out; | |
308 | } | |
309 | ||
310 | /* | |
311 | * 6. Check optional user data format | |
312 | */ | |
313 | err++; | |
314 | if (menuver & DN_MENUVER_USR) { | |
315 | if (dn_check_idf(&ptr, &len, 16, 0)) | |
316 | goto err_out; | |
317 | } | |
318 | ||
319 | /* | |
320 | * 7. Look up socket based on destination end username | |
321 | */ | |
322 | return dn_sklist_find_listener(&dstaddr); | |
323 | err_out: | |
324 | dn_log_martian(skb, ci_err_table[err].text); | |
325 | *reason = ci_err_table[err].reason; | |
326 | return NULL; | |
327 | } | |
328 | ||
329 | ||
330 | static void dn_nsp_conn_init(struct sock *sk, struct sk_buff *skb) | |
331 | { | |
332 | if (sk_acceptq_is_full(sk)) { | |
333 | kfree_skb(skb); | |
334 | return; | |
335 | } | |
336 | ||
337 | sk->sk_ack_backlog++; | |
338 | skb_queue_tail(&sk->sk_receive_queue, skb); | |
339 | sk->sk_state_change(sk); | |
340 | } | |
341 | ||
342 | static void dn_nsp_conn_conf(struct sock *sk, struct sk_buff *skb) | |
343 | { | |
344 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | |
345 | struct dn_scp *scp = DN_SK(sk); | |
346 | unsigned char *ptr; | |
347 | ||
348 | if (skb->len < 4) | |
349 | goto out; | |
350 | ||
351 | ptr = skb->data; | |
352 | cb->services = *ptr++; | |
353 | cb->info = *ptr++; | |
c4106aa8 | 354 | cb->segsize = le16_to_cpu(*(__le16 *)ptr); |
1da177e4 LT |
355 | |
356 | if ((scp->state == DN_CI) || (scp->state == DN_CD)) { | |
357 | scp->persist = 0; | |
429eb0fa YH |
358 | scp->addrrem = cb->src_port; |
359 | sk->sk_state = TCP_ESTABLISHED; | |
360 | scp->state = DN_RUN; | |
1da177e4 LT |
361 | scp->services_rem = cb->services; |
362 | scp->info_rem = cb->info; | |
363 | scp->segsize_rem = cb->segsize; | |
364 | ||
365 | if ((scp->services_rem & NSP_FC_MASK) == NSP_FC_NONE) | |
366 | scp->max_window = decnet_no_fc_max_cwnd; | |
367 | ||
368 | if (skb->len > 0) { | |
375d9d71 | 369 | u16 dlen = *skb->data; |
1da177e4 | 370 | if ((dlen <= 16) && (dlen <= skb->len)) { |
c4106aa8 | 371 | scp->conndata_in.opt_optl = cpu_to_le16(dlen); |
d626f62b ACM |
372 | skb_copy_from_linear_data_offset(skb, 1, |
373 | scp->conndata_in.opt_data, dlen); | |
1da177e4 LT |
374 | } |
375 | } | |
429eb0fa YH |
376 | dn_nsp_send_link(sk, DN_NOCHANGE, 0); |
377 | if (!sock_flag(sk, SOCK_DEAD)) | |
378 | sk->sk_state_change(sk); | |
379 | } | |
1da177e4 LT |
380 | |
381 | out: | |
429eb0fa | 382 | kfree_skb(skb); |
1da177e4 LT |
383 | } |
384 | ||
385 | static void dn_nsp_conn_ack(struct sock *sk, struct sk_buff *skb) | |
386 | { | |
387 | struct dn_scp *scp = DN_SK(sk); | |
388 | ||
389 | if (scp->state == DN_CI) { | |
390 | scp->state = DN_CD; | |
391 | scp->persist = 0; | |
392 | } | |
393 | ||
394 | kfree_skb(skb); | |
395 | } | |
396 | ||
397 | static void dn_nsp_disc_init(struct sock *sk, struct sk_buff *skb) | |
398 | { | |
399 | struct dn_scp *scp = DN_SK(sk); | |
400 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | |
401 | unsigned short reason; | |
402 | ||
403 | if (skb->len < 2) | |
404 | goto out; | |
405 | ||
c4106aa8 | 406 | reason = le16_to_cpu(*(__le16 *)skb->data); |
1da177e4 LT |
407 | skb_pull(skb, 2); |
408 | ||
c4106aa8 | 409 | scp->discdata_in.opt_status = cpu_to_le16(reason); |
1da177e4 LT |
410 | scp->discdata_in.opt_optl = 0; |
411 | memset(scp->discdata_in.opt_data, 0, 16); | |
412 | ||
413 | if (skb->len > 0) { | |
375d9d71 | 414 | u16 dlen = *skb->data; |
1da177e4 | 415 | if ((dlen <= 16) && (dlen <= skb->len)) { |
c4106aa8 | 416 | scp->discdata_in.opt_optl = cpu_to_le16(dlen); |
d626f62b | 417 | skb_copy_from_linear_data_offset(skb, 1, scp->discdata_in.opt_data, dlen); |
1da177e4 LT |
418 | } |
419 | } | |
420 | ||
421 | scp->addrrem = cb->src_port; | |
422 | sk->sk_state = TCP_CLOSE; | |
423 | ||
06f8fe11 JP |
424 | switch (scp->state) { |
425 | case DN_CI: | |
426 | case DN_CD: | |
427 | scp->state = DN_RJ; | |
428 | sk->sk_err = ECONNREFUSED; | |
429 | break; | |
430 | case DN_RUN: | |
431 | sk->sk_shutdown |= SHUTDOWN_MASK; | |
432 | scp->state = DN_DN; | |
433 | break; | |
434 | case DN_DI: | |
435 | scp->state = DN_DIC; | |
436 | break; | |
1da177e4 LT |
437 | } |
438 | ||
439 | if (!sock_flag(sk, SOCK_DEAD)) { | |
440 | if (sk->sk_socket->state != SS_UNCONNECTED) | |
441 | sk->sk_socket->state = SS_DISCONNECTING; | |
442 | sk->sk_state_change(sk); | |
443 | } | |
444 | ||
429eb0fa | 445 | /* |
1da177e4 LT |
446 | * It appears that its possible for remote machines to send disc |
447 | * init messages with no port identifier if we are in the CI and | |
448 | * possibly also the CD state. Obviously we shouldn't reply with | |
449 | * a message if we don't know what the end point is. | |
450 | */ | |
451 | if (scp->addrrem) { | |
452 | dn_nsp_send_disc(sk, NSP_DISCCONF, NSP_REASON_DC, GFP_ATOMIC); | |
453 | } | |
454 | scp->persist_fxn = dn_destroy_timer; | |
455 | scp->persist = dn_nsp_persist(sk); | |
456 | ||
457 | out: | |
458 | kfree_skb(skb); | |
459 | } | |
460 | ||
461 | /* | |
462 | * disc_conf messages are also called no_resources or no_link | |
463 | * messages depending upon the "reason" field. | |
464 | */ | |
465 | static void dn_nsp_disc_conf(struct sock *sk, struct sk_buff *skb) | |
466 | { | |
467 | struct dn_scp *scp = DN_SK(sk); | |
468 | unsigned short reason; | |
469 | ||
470 | if (skb->len != 2) | |
471 | goto out; | |
472 | ||
c4106aa8 | 473 | reason = le16_to_cpu(*(__le16 *)skb->data); |
1da177e4 LT |
474 | |
475 | sk->sk_state = TCP_CLOSE; | |
476 | ||
06f8fe11 JP |
477 | switch (scp->state) { |
478 | case DN_CI: | |
479 | scp->state = DN_NR; | |
480 | break; | |
481 | case DN_DR: | |
482 | if (reason == NSP_REASON_DC) | |
483 | scp->state = DN_DRC; | |
484 | if (reason == NSP_REASON_NL) | |
1da177e4 | 485 | scp->state = DN_CN; |
06f8fe11 JP |
486 | break; |
487 | case DN_DI: | |
488 | scp->state = DN_DIC; | |
489 | break; | |
490 | case DN_RUN: | |
491 | sk->sk_shutdown |= SHUTDOWN_MASK; | |
492 | case DN_CC: | |
493 | scp->state = DN_CN; | |
1da177e4 LT |
494 | } |
495 | ||
496 | if (!sock_flag(sk, SOCK_DEAD)) { | |
497 | if (sk->sk_socket->state != SS_UNCONNECTED) | |
498 | sk->sk_socket->state = SS_DISCONNECTING; | |
499 | sk->sk_state_change(sk); | |
500 | } | |
501 | ||
502 | scp->persist_fxn = dn_destroy_timer; | |
503 | scp->persist = dn_nsp_persist(sk); | |
504 | ||
505 | out: | |
506 | kfree_skb(skb); | |
507 | } | |
508 | ||
509 | static void dn_nsp_linkservice(struct sock *sk, struct sk_buff *skb) | |
510 | { | |
511 | struct dn_scp *scp = DN_SK(sk); | |
512 | unsigned short segnum; | |
513 | unsigned char lsflags; | |
514 | signed char fcval; | |
515 | int wake_up = 0; | |
516 | char *ptr = skb->data; | |
517 | unsigned char fctype = scp->services_rem & NSP_FC_MASK; | |
518 | ||
519 | if (skb->len != 4) | |
520 | goto out; | |
521 | ||
c4106aa8 | 522 | segnum = le16_to_cpu(*(__le16 *)ptr); |
1da177e4 LT |
523 | ptr += 2; |
524 | lsflags = *(unsigned char *)ptr++; | |
525 | fcval = *ptr; | |
526 | ||
527 | /* | |
528 | * Here we ignore erronous packets which should really | |
429eb0fa | 529 | * should cause a connection abort. It is not critical |
1da177e4 LT |
530 | * for now though. |
531 | */ | |
532 | if (lsflags & 0xf8) | |
533 | goto out; | |
534 | ||
535 | if (seq_next(scp->numoth_rcv, segnum)) { | |
536 | seq_add(&scp->numoth_rcv, 1); | |
537 | switch(lsflags & 0x04) { /* FCVAL INT */ | |
538 | case 0x00: /* Normal Request */ | |
539 | switch(lsflags & 0x03) { /* FCVAL MOD */ | |
429eb0fa | 540 | case 0x00: /* Request count */ |
1da177e4 LT |
541 | if (fcval < 0) { |
542 | unsigned char p_fcval = -fcval; | |
543 | if ((scp->flowrem_dat > p_fcval) && | |
544 | (fctype == NSP_FC_SCMC)) { | |
545 | scp->flowrem_dat -= p_fcval; | |
546 | } | |
547 | } else if (fcval > 0) { | |
548 | scp->flowrem_dat += fcval; | |
549 | wake_up = 1; | |
550 | } | |
429eb0fa | 551 | break; |
1da177e4 LT |
552 | case 0x01: /* Stop outgoing data */ |
553 | scp->flowrem_sw = DN_DONTSEND; | |
554 | break; | |
555 | case 0x02: /* Ok to start again */ | |
556 | scp->flowrem_sw = DN_SEND; | |
557 | dn_nsp_output(sk); | |
558 | wake_up = 1; | |
559 | } | |
560 | break; | |
561 | case 0x04: /* Interrupt Request */ | |
562 | if (fcval > 0) { | |
563 | scp->flowrem_oth += fcval; | |
564 | wake_up = 1; | |
565 | } | |
566 | break; | |
429eb0fa | 567 | } |
1da177e4 LT |
568 | if (wake_up && !sock_flag(sk, SOCK_DEAD)) |
569 | sk->sk_state_change(sk); | |
429eb0fa | 570 | } |
1da177e4 LT |
571 | |
572 | dn_nsp_send_oth_ack(sk); | |
573 | ||
574 | out: | |
575 | kfree_skb(skb); | |
576 | } | |
577 | ||
578 | /* | |
579 | * Copy of sock_queue_rcv_skb (from sock.h) without | |
580 | * bh_lock_sock() (its already held when this is called) which | |
581 | * also allows data and other data to be queued to a socket. | |
582 | */ | |
583 | static __inline__ int dn_queue_skb(struct sock *sk, struct sk_buff *skb, int sig, struct sk_buff_head *queue) | |
584 | { | |
585 | int err; | |
9948bb6a | 586 | int skb_len; |
429eb0fa YH |
587 | |
588 | /* Cast skb->rcvbuf to unsigned... It's pointless, but reduces | |
589 | number of warnings when compiling with -W --ANK | |
590 | */ | |
591 | if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= | |
1da177e4 | 592 | (unsigned)sk->sk_rcvbuf) { |
429eb0fa YH |
593 | err = -ENOMEM; |
594 | goto out; | |
595 | } | |
1da177e4 | 596 | |
fda9ef5d | 597 | err = sk_filter(sk, skb); |
1da177e4 LT |
598 | if (err) |
599 | goto out; | |
600 | ||
9948bb6a | 601 | skb_len = skb->len; |
429eb0fa YH |
602 | skb_set_owner_r(skb, sk); |
603 | skb_queue_tail(queue, skb); | |
1da177e4 | 604 | |
9948bb6a SW |
605 | if (!sock_flag(sk, SOCK_DEAD)) |
606 | sk->sk_data_ready(sk, skb_len); | |
1da177e4 | 607 | out: |
429eb0fa | 608 | return err; |
1da177e4 LT |
609 | } |
610 | ||
611 | static void dn_nsp_otherdata(struct sock *sk, struct sk_buff *skb) | |
612 | { | |
613 | struct dn_scp *scp = DN_SK(sk); | |
614 | unsigned short segnum; | |
615 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | |
616 | int queued = 0; | |
617 | ||
618 | if (skb->len < 2) | |
619 | goto out; | |
620 | ||
c4106aa8 | 621 | cb->segnum = segnum = le16_to_cpu(*(__le16 *)skb->data); |
1da177e4 LT |
622 | skb_pull(skb, 2); |
623 | ||
624 | if (seq_next(scp->numoth_rcv, segnum)) { | |
625 | ||
626 | if (dn_queue_skb(sk, skb, SIGURG, &scp->other_receive_queue) == 0) { | |
627 | seq_add(&scp->numoth_rcv, 1); | |
628 | scp->other_report = 0; | |
629 | queued = 1; | |
630 | } | |
631 | } | |
632 | ||
633 | dn_nsp_send_oth_ack(sk); | |
634 | out: | |
635 | if (!queued) | |
636 | kfree_skb(skb); | |
637 | } | |
638 | ||
639 | static void dn_nsp_data(struct sock *sk, struct sk_buff *skb) | |
640 | { | |
641 | int queued = 0; | |
642 | unsigned short segnum; | |
643 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | |
644 | struct dn_scp *scp = DN_SK(sk); | |
645 | ||
646 | if (skb->len < 2) | |
647 | goto out; | |
648 | ||
c4106aa8 | 649 | cb->segnum = segnum = le16_to_cpu(*(__le16 *)skb->data); |
1da177e4 LT |
650 | skb_pull(skb, 2); |
651 | ||
652 | if (seq_next(scp->numdat_rcv, segnum)) { | |
429eb0fa | 653 | if (dn_queue_skb(sk, skb, SIGIO, &sk->sk_receive_queue) == 0) { |
1da177e4 | 654 | seq_add(&scp->numdat_rcv, 1); |
429eb0fa YH |
655 | queued = 1; |
656 | } | |
1da177e4 LT |
657 | |
658 | if ((scp->flowloc_sw == DN_SEND) && dn_congested(sk)) { | |
659 | scp->flowloc_sw = DN_DONTSEND; | |
660 | dn_nsp_send_link(sk, DN_DONTSEND, 0); | |
661 | } | |
429eb0fa | 662 | } |
1da177e4 LT |
663 | |
664 | dn_nsp_send_data_ack(sk); | |
665 | out: | |
666 | if (!queued) | |
667 | kfree_skb(skb); | |
668 | } | |
669 | ||
670 | /* | |
671 | * If one of our conninit messages is returned, this function | |
672 | * deals with it. It puts the socket into the NO_COMMUNICATION | |
673 | * state. | |
674 | */ | |
675 | static void dn_returned_conn_init(struct sock *sk, struct sk_buff *skb) | |
676 | { | |
677 | struct dn_scp *scp = DN_SK(sk); | |
678 | ||
679 | if (scp->state == DN_CI) { | |
680 | scp->state = DN_NC; | |
681 | sk->sk_state = TCP_CLOSE; | |
682 | if (!sock_flag(sk, SOCK_DEAD)) | |
683 | sk->sk_state_change(sk); | |
684 | } | |
685 | ||
686 | kfree_skb(skb); | |
687 | } | |
688 | ||
689 | static int dn_nsp_no_socket(struct sk_buff *skb, unsigned short reason) | |
690 | { | |
691 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | |
692 | int ret = NET_RX_DROP; | |
693 | ||
694 | /* Must not reply to returned packets */ | |
695 | if (cb->rt_flags & DN_RT_F_RTS) | |
696 | goto out; | |
697 | ||
698 | if ((reason != NSP_REASON_OK) && ((cb->nsp_flags & 0x0c) == 0x08)) { | |
06f8fe11 JP |
699 | switch (cb->nsp_flags & 0x70) { |
700 | case 0x10: | |
701 | case 0x60: /* (Retransmitted) Connect Init */ | |
702 | dn_nsp_return_disc(skb, NSP_DISCINIT, reason); | |
703 | ret = NET_RX_SUCCESS; | |
704 | break; | |
705 | case 0x20: /* Connect Confirm */ | |
706 | dn_nsp_return_disc(skb, NSP_DISCCONF, reason); | |
707 | ret = NET_RX_SUCCESS; | |
708 | break; | |
1da177e4 LT |
709 | } |
710 | } | |
711 | ||
712 | out: | |
713 | kfree_skb(skb); | |
714 | return ret; | |
715 | } | |
716 | ||
717 | static int dn_nsp_rx_packet(struct sk_buff *skb) | |
718 | { | |
719 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | |
720 | struct sock *sk = NULL; | |
721 | unsigned char *ptr = (unsigned char *)skb->data; | |
722 | unsigned short reason = NSP_REASON_NL; | |
723 | ||
724 | if (!pskb_may_pull(skb, 2)) | |
725 | goto free_out; | |
726 | ||
badff6d0 | 727 | skb_reset_transport_header(skb); |
1da177e4 LT |
728 | cb->nsp_flags = *ptr++; |
729 | ||
730 | if (decnet_debug_level & 2) | |
731 | printk(KERN_DEBUG "dn_nsp_rx: Message type 0x%02x\n", (int)cb->nsp_flags); | |
732 | ||
429eb0fa | 733 | if (cb->nsp_flags & 0x83) |
1da177e4 LT |
734 | goto free_out; |
735 | ||
736 | /* | |
737 | * Filter out conninits and useless packet types | |
738 | */ | |
739 | if ((cb->nsp_flags & 0x0c) == 0x08) { | |
06f8fe11 JP |
740 | switch (cb->nsp_flags & 0x70) { |
741 | case 0x00: /* NOP */ | |
742 | case 0x70: /* Reserved */ | |
743 | case 0x50: /* Reserved, Phase II node init */ | |
744 | goto free_out; | |
745 | case 0x10: | |
746 | case 0x60: | |
747 | if (unlikely(cb->rt_flags & DN_RT_F_RTS)) | |
1da177e4 | 748 | goto free_out; |
06f8fe11 JP |
749 | sk = dn_find_listener(skb, &reason); |
750 | goto got_it; | |
1da177e4 LT |
751 | } |
752 | } | |
753 | ||
754 | if (!pskb_may_pull(skb, 3)) | |
755 | goto free_out; | |
756 | ||
757 | /* | |
758 | * Grab the destination address. | |
759 | */ | |
c4ea94ab | 760 | cb->dst_port = *(__le16 *)ptr; |
1da177e4 LT |
761 | cb->src_port = 0; |
762 | ptr += 2; | |
763 | ||
764 | /* | |
765 | * If not a connack, grab the source address too. | |
766 | */ | |
767 | if (pskb_may_pull(skb, 5)) { | |
c4ea94ab | 768 | cb->src_port = *(__le16 *)ptr; |
1da177e4 LT |
769 | ptr += 2; |
770 | skb_pull(skb, 5); | |
771 | } | |
772 | ||
773 | /* | |
774 | * Returned packets... | |
775 | * Swap src & dst and look up in the normal way. | |
776 | */ | |
777 | if (unlikely(cb->rt_flags & DN_RT_F_RTS)) { | |
c4ea94ab | 778 | __le16 tmp = cb->dst_port; |
1da177e4 LT |
779 | cb->dst_port = cb->src_port; |
780 | cb->src_port = tmp; | |
781 | tmp = cb->dst; | |
782 | cb->dst = cb->src; | |
783 | cb->src = tmp; | |
784 | } | |
785 | ||
786 | /* | |
787 | * Find the socket to which this skb is destined. | |
788 | */ | |
789 | sk = dn_find_by_skb(skb); | |
790 | got_it: | |
791 | if (sk != NULL) { | |
792 | struct dn_scp *scp = DN_SK(sk); | |
1da177e4 LT |
793 | |
794 | /* Reset backoff */ | |
795 | scp->nsp_rxtshift = 0; | |
796 | ||
797 | /* | |
798 | * We linearize everything except data segments here. | |
799 | */ | |
800 | if (cb->nsp_flags & ~0x60) { | |
364c6bad | 801 | if (unlikely(skb_linearize(skb))) |
1da177e4 LT |
802 | goto free_out; |
803 | } | |
804 | ||
58a5a7b9 | 805 | return sk_receive_skb(sk, skb, 0); |
1da177e4 LT |
806 | } |
807 | ||
808 | return dn_nsp_no_socket(skb, reason); | |
809 | ||
810 | free_out: | |
811 | kfree_skb(skb); | |
812 | return NET_RX_DROP; | |
813 | } | |
814 | ||
815 | int dn_nsp_rx(struct sk_buff *skb) | |
816 | { | |
5d877d87 JE |
817 | return NF_HOOK(NFPROTO_DECNET, NF_DN_LOCAL_IN, skb, skb->dev, NULL, |
818 | dn_nsp_rx_packet); | |
1da177e4 LT |
819 | } |
820 | ||
821 | /* | |
822 | * This is the main receive routine for sockets. It is called | |
823 | * from the above when the socket is not busy, and also from | |
824 | * sock_release() when there is a backlog queued up. | |
825 | */ | |
826 | int dn_nsp_backlog_rcv(struct sock *sk, struct sk_buff *skb) | |
827 | { | |
828 | struct dn_scp *scp = DN_SK(sk); | |
829 | struct dn_skb_cb *cb = DN_SKB_CB(skb); | |
830 | ||
831 | if (cb->rt_flags & DN_RT_F_RTS) { | |
832 | if (cb->nsp_flags == 0x18 || cb->nsp_flags == 0x68) | |
833 | dn_returned_conn_init(sk, skb); | |
834 | else | |
835 | kfree_skb(skb); | |
836 | return NET_RX_SUCCESS; | |
837 | } | |
838 | ||
839 | /* | |
840 | * Control packet. | |
841 | */ | |
842 | if ((cb->nsp_flags & 0x0c) == 0x08) { | |
06f8fe11 JP |
843 | switch (cb->nsp_flags & 0x70) { |
844 | case 0x10: | |
845 | case 0x60: | |
846 | dn_nsp_conn_init(sk, skb); | |
847 | break; | |
848 | case 0x20: | |
849 | dn_nsp_conn_conf(sk, skb); | |
850 | break; | |
851 | case 0x30: | |
852 | dn_nsp_disc_init(sk, skb); | |
853 | break; | |
854 | case 0x40: | |
855 | dn_nsp_disc_conf(sk, skb); | |
856 | break; | |
1da177e4 LT |
857 | } |
858 | ||
859 | } else if (cb->nsp_flags == 0x24) { | |
860 | /* | |
861 | * Special for connacks, 'cos they don't have | |
862 | * ack data or ack otherdata info. | |
863 | */ | |
864 | dn_nsp_conn_ack(sk, skb); | |
865 | } else { | |
866 | int other = 1; | |
867 | ||
868 | /* both data and ack frames can kick a CC socket into RUN */ | |
869 | if ((scp->state == DN_CC) && !sock_flag(sk, SOCK_DEAD)) { | |
870 | scp->state = DN_RUN; | |
871 | sk->sk_state = TCP_ESTABLISHED; | |
872 | sk->sk_state_change(sk); | |
873 | } | |
874 | ||
875 | if ((cb->nsp_flags & 0x1c) == 0) | |
876 | other = 0; | |
877 | if (cb->nsp_flags == 0x04) | |
878 | other = 0; | |
879 | ||
880 | /* | |
881 | * Read out ack data here, this applies equally | |
882 | * to data, other data, link serivce and both | |
883 | * ack data and ack otherdata. | |
884 | */ | |
885 | dn_process_ack(sk, skb, other); | |
886 | ||
887 | /* | |
888 | * If we've some sort of data here then call a | |
889 | * suitable routine for dealing with it, otherwise | |
890 | * the packet is an ack and can be discarded. | |
891 | */ | |
892 | if ((cb->nsp_flags & 0x0c) == 0) { | |
893 | ||
894 | if (scp->state != DN_RUN) | |
895 | goto free_out; | |
896 | ||
06f8fe11 JP |
897 | switch (cb->nsp_flags) { |
898 | case 0x10: /* LS */ | |
899 | dn_nsp_linkservice(sk, skb); | |
900 | break; | |
901 | case 0x30: /* OD */ | |
902 | dn_nsp_otherdata(sk, skb); | |
903 | break; | |
904 | default: | |
905 | dn_nsp_data(sk, skb); | |
1da177e4 LT |
906 | } |
907 | ||
908 | } else { /* Ack, chuck it out here */ | |
909 | free_out: | |
910 | kfree_skb(skb); | |
911 | } | |
912 | } | |
913 | ||
914 | return NET_RX_SUCCESS; | |
915 | } | |
916 |