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 Intel Corp. | |
6 | * Copyright (c) 2001 Nokia, Inc. | |
7 | * Copyright (c) 2001 La Monte H.P. Yarroll | |
8 | * | |
9 | * This abstraction carries sctp events to the ULP (sockets). | |
10 | * | |
60c778b2 | 11 | * This SCTP implementation is free software; |
1da177e4 LT |
12 | * you can redistribute it and/or modify it under the terms of |
13 | * the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2, or (at your option) | |
15 | * any later version. | |
16 | * | |
60c778b2 | 17 | * This SCTP implementation is distributed in the hope that it |
1da177e4 LT |
18 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
19 | * ************************ | |
20 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
21 | * See the GNU General Public License for more details. | |
22 | * | |
23 | * You should have received a copy of the GNU General Public License | |
4b2f13a2 JK |
24 | * along with GNU CC; see the file COPYING. If not, see |
25 | * <http://www.gnu.org/licenses/>. | |
1da177e4 LT |
26 | * |
27 | * Please send any bug reports or fixes you make to the | |
28 | * email address(es): | |
91705c61 | 29 | * lksctp developers <linux-sctp@vger.kernel.org> |
1da177e4 | 30 | * |
1da177e4 LT |
31 | * Written or modified by: |
32 | * Jon Grimm <jgrimm@us.ibm.com> | |
33 | * La Monte H.P. Yarroll <piggy@acm.org> | |
34 | * Sridhar Samudrala <sri@us.ibm.com> | |
1da177e4 LT |
35 | */ |
36 | ||
5a0e3ad6 | 37 | #include <linux/slab.h> |
1da177e4 LT |
38 | #include <linux/types.h> |
39 | #include <linux/skbuff.h> | |
40 | #include <net/sock.h> | |
8465a5fc | 41 | #include <net/busy_poll.h> |
1da177e4 LT |
42 | #include <net/sctp/structs.h> |
43 | #include <net/sctp/sctp.h> | |
44 | #include <net/sctp/sm.h> | |
45 | ||
46 | /* Forward declarations for internal helpers. */ | |
26ac8e5f | 47 | static struct sctp_ulpevent *sctp_ulpq_reasm(struct sctp_ulpq *ulpq, |
8728b834 | 48 | struct sctp_ulpevent *); |
26ac8e5f | 49 | static struct sctp_ulpevent *sctp_ulpq_order(struct sctp_ulpq *, |
8728b834 | 50 | struct sctp_ulpevent *); |
ef5d4cf2 | 51 | static void sctp_ulpq_reasm_drain(struct sctp_ulpq *ulpq); |
1da177e4 LT |
52 | |
53 | /* 1st Level Abstractions */ | |
54 | ||
55 | /* Initialize a ULP queue from a block of memory. */ | |
56 | struct sctp_ulpq *sctp_ulpq_init(struct sctp_ulpq *ulpq, | |
57 | struct sctp_association *asoc) | |
58 | { | |
59 | memset(ulpq, 0, sizeof(struct sctp_ulpq)); | |
60 | ||
61 | ulpq->asoc = asoc; | |
62 | skb_queue_head_init(&ulpq->reasm); | |
63 | skb_queue_head_init(&ulpq->lobby); | |
64 | ulpq->pd_mode = 0; | |
1da177e4 LT |
65 | |
66 | return ulpq; | |
67 | } | |
68 | ||
69 | ||
70 | /* Flush the reassembly and ordering queues. */ | |
0b58a811 | 71 | void sctp_ulpq_flush(struct sctp_ulpq *ulpq) |
1da177e4 LT |
72 | { |
73 | struct sk_buff *skb; | |
74 | struct sctp_ulpevent *event; | |
75 | ||
76 | while ((skb = __skb_dequeue(&ulpq->lobby)) != NULL) { | |
77 | event = sctp_skb2event(skb); | |
78 | sctp_ulpevent_free(event); | |
79 | } | |
80 | ||
81 | while ((skb = __skb_dequeue(&ulpq->reasm)) != NULL) { | |
82 | event = sctp_skb2event(skb); | |
83 | sctp_ulpevent_free(event); | |
84 | } | |
85 | ||
86 | } | |
87 | ||
88 | /* Dispose of a ulpqueue. */ | |
89 | void sctp_ulpq_free(struct sctp_ulpq *ulpq) | |
90 | { | |
91 | sctp_ulpq_flush(ulpq); | |
1da177e4 LT |
92 | } |
93 | ||
94 | /* Process an incoming DATA chunk. */ | |
95 | int sctp_ulpq_tail_data(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk, | |
dd0fc66f | 96 | gfp_t gfp) |
1da177e4 LT |
97 | { |
98 | struct sk_buff_head temp; | |
1da177e4 | 99 | struct sctp_ulpevent *event; |
d003b41b | 100 | int event_eor = 0; |
1da177e4 | 101 | |
1da177e4 LT |
102 | /* Create an event from the incoming chunk. */ |
103 | event = sctp_ulpevent_make_rcvmsg(chunk->asoc, chunk, gfp); | |
104 | if (!event) | |
105 | return -ENOMEM; | |
106 | ||
107 | /* Do reassembly if needed. */ | |
108 | event = sctp_ulpq_reasm(ulpq, event); | |
109 | ||
110 | /* Do ordering if needed. */ | |
cb3f837b | 111 | if ((event) && (event->msg_flags & MSG_EOR)) { |
1da177e4 LT |
112 | /* Create a temporary list to collect chunks on. */ |
113 | skb_queue_head_init(&temp); | |
114 | __skb_queue_tail(&temp, sctp_event2skb(event)); | |
115 | ||
116 | event = sctp_ulpq_order(ulpq, event); | |
117 | } | |
118 | ||
8728b834 DM |
119 | /* Send event to the ULP. 'event' is the sctp_ulpevent for |
120 | * very first SKB on the 'temp' list. | |
121 | */ | |
d003b41b LR |
122 | if (event) { |
123 | event_eor = (event->msg_flags & MSG_EOR) ? 1 : 0; | |
1da177e4 | 124 | sctp_ulpq_tail_event(ulpq, event); |
d003b41b | 125 | } |
1da177e4 | 126 | |
d003b41b | 127 | return event_eor; |
1da177e4 LT |
128 | } |
129 | ||
130 | /* Add a new event for propagation to the ULP. */ | |
131 | /* Clear the partial delivery mode for this socket. Note: This | |
132 | * assumes that no association is currently in partial delivery mode. | |
133 | */ | |
b6e1331f | 134 | int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc) |
1da177e4 LT |
135 | { |
136 | struct sctp_sock *sp = sctp_sk(sk); | |
137 | ||
b6e1331f VY |
138 | if (atomic_dec_and_test(&sp->pd_mode)) { |
139 | /* This means there are no other associations in PD, so | |
140 | * we can go ahead and clear out the lobby in one shot | |
141 | */ | |
142 | if (!skb_queue_empty(&sp->pd_lobby)) { | |
143 | struct list_head *list; | |
144 | sctp_skb_list_tail(&sp->pd_lobby, &sk->sk_receive_queue); | |
145 | list = (struct list_head *)&sctp_sk(sk)->pd_lobby; | |
146 | INIT_LIST_HEAD(list); | |
147 | return 1; | |
148 | } | |
149 | } else { | |
150 | /* There are other associations in PD, so we only need to | |
151 | * pull stuff out of the lobby that belongs to the | |
152 | * associations that is exiting PD (all of its notifications | |
153 | * are posted here). | |
154 | */ | |
155 | if (!skb_queue_empty(&sp->pd_lobby) && asoc) { | |
156 | struct sk_buff *skb, *tmp; | |
157 | struct sctp_ulpevent *event; | |
158 | ||
159 | sctp_skb_for_each(skb, &sp->pd_lobby, tmp) { | |
160 | event = sctp_skb2event(skb); | |
161 | if (event->asoc == asoc) { | |
162 | __skb_unlink(skb, &sp->pd_lobby); | |
163 | __skb_queue_tail(&sk->sk_receive_queue, | |
164 | skb); | |
165 | } | |
166 | } | |
167 | } | |
1da177e4 | 168 | } |
b6e1331f | 169 | |
1da177e4 LT |
170 | return 0; |
171 | } | |
172 | ||
d49d91d7 VY |
173 | /* Set the pd_mode on the socket and ulpq */ |
174 | static void sctp_ulpq_set_pd(struct sctp_ulpq *ulpq) | |
175 | { | |
176 | struct sctp_sock *sp = sctp_sk(ulpq->asoc->base.sk); | |
177 | ||
178 | atomic_inc(&sp->pd_mode); | |
179 | ulpq->pd_mode = 1; | |
180 | } | |
181 | ||
1da177e4 LT |
182 | /* Clear the pd_mode and restart any pending messages waiting for delivery. */ |
183 | static int sctp_ulpq_clear_pd(struct sctp_ulpq *ulpq) | |
184 | { | |
185 | ulpq->pd_mode = 0; | |
ef5d4cf2 | 186 | sctp_ulpq_reasm_drain(ulpq); |
b6e1331f | 187 | return sctp_clear_pd(ulpq->asoc->base.sk, ulpq->asoc); |
1da177e4 LT |
188 | } |
189 | ||
8728b834 DM |
190 | /* If the SKB of 'event' is on a list, it is the first such member |
191 | * of that list. | |
192 | */ | |
1da177e4 LT |
193 | int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event) |
194 | { | |
195 | struct sock *sk = ulpq->asoc->base.sk; | |
8728b834 DM |
196 | struct sk_buff_head *queue, *skb_list; |
197 | struct sk_buff *skb = sctp_event2skb(event); | |
1da177e4 LT |
198 | int clear_pd = 0; |
199 | ||
8728b834 DM |
200 | skb_list = (struct sk_buff_head *) skb->prev; |
201 | ||
1da177e4 LT |
202 | /* If the socket is just going to throw this away, do not |
203 | * even try to deliver it. | |
204 | */ | |
205 | if (sock_flag(sk, SOCK_DEAD) || (sk->sk_shutdown & RCV_SHUTDOWN)) | |
206 | goto out_free; | |
207 | ||
2c8c56e1 | 208 | if (!sctp_ulpevent_is_notification(event)) { |
8465a5fc | 209 | sk_mark_napi_id(sk, skb); |
2c8c56e1 ED |
210 | sk_incoming_cpu_update(sk); |
211 | } | |
1da177e4 LT |
212 | /* Check if the user wishes to receive this event. */ |
213 | if (!sctp_ulpevent_is_enabled(event, &sctp_sk(sk)->subscribe)) | |
214 | goto out_free; | |
215 | ||
216 | /* If we are in partial delivery mode, post to the lobby until | |
217 | * partial delivery is cleared, unless, of course _this_ is | |
218 | * the association the cause of the partial delivery. | |
219 | */ | |
220 | ||
b6e1331f | 221 | if (atomic_read(&sctp_sk(sk)->pd_mode) == 0) { |
1da177e4 | 222 | queue = &sk->sk_receive_queue; |
b6e1331f VY |
223 | } else { |
224 | if (ulpq->pd_mode) { | |
225 | /* If the association is in partial delivery, we | |
226 | * need to finish delivering the partially processed | |
227 | * packet before passing any other data. This is | |
228 | * because we don't truly support stream interleaving. | |
229 | */ | |
230 | if ((event->msg_flags & MSG_NOTIFICATION) || | |
231 | (SCTP_DATA_NOT_FRAG == | |
232 | (event->msg_flags & SCTP_DATA_FRAG_MASK))) | |
233 | queue = &sctp_sk(sk)->pd_lobby; | |
234 | else { | |
235 | clear_pd = event->msg_flags & MSG_EOR; | |
236 | queue = &sk->sk_receive_queue; | |
237 | } | |
238 | } else { | |
239 | /* | |
240 | * If fragment interleave is enabled, we | |
25985edc | 241 | * can queue this to the receive queue instead |
b6e1331f VY |
242 | * of the lobby. |
243 | */ | |
244 | if (sctp_sk(sk)->frag_interleave) | |
245 | queue = &sk->sk_receive_queue; | |
246 | else | |
247 | queue = &sctp_sk(sk)->pd_lobby; | |
1da177e4 | 248 | } |
b6e1331f | 249 | } |
1da177e4 LT |
250 | |
251 | /* If we are harvesting multiple skbs they will be | |
252 | * collected on a list. | |
253 | */ | |
8728b834 DM |
254 | if (skb_list) |
255 | sctp_skb_list_tail(skb_list, queue); | |
1da177e4 | 256 | else |
8728b834 | 257 | __skb_queue_tail(queue, skb); |
1da177e4 LT |
258 | |
259 | /* Did we just complete partial delivery and need to get | |
260 | * rolling again? Move pending data to the receive | |
261 | * queue. | |
262 | */ | |
263 | if (clear_pd) | |
264 | sctp_ulpq_clear_pd(ulpq); | |
265 | ||
266 | if (queue == &sk->sk_receive_queue) | |
676d2369 | 267 | sk->sk_data_ready(sk); |
1da177e4 LT |
268 | return 1; |
269 | ||
270 | out_free: | |
8728b834 DM |
271 | if (skb_list) |
272 | sctp_queue_purge_ulpevents(skb_list); | |
1da177e4 LT |
273 | else |
274 | sctp_ulpevent_free(event); | |
8728b834 | 275 | |
1da177e4 LT |
276 | return 0; |
277 | } | |
278 | ||
279 | /* 2nd Level Abstractions */ | |
280 | ||
281 | /* Helper function to store chunks that need to be reassembled. */ | |
01f2d384 | 282 | static void sctp_ulpq_store_reasm(struct sctp_ulpq *ulpq, |
1da177e4 LT |
283 | struct sctp_ulpevent *event) |
284 | { | |
285 | struct sk_buff *pos; | |
286 | struct sctp_ulpevent *cevent; | |
287 | __u32 tsn, ctsn; | |
288 | ||
289 | tsn = event->tsn; | |
290 | ||
291 | /* See if it belongs at the end. */ | |
292 | pos = skb_peek_tail(&ulpq->reasm); | |
293 | if (!pos) { | |
294 | __skb_queue_tail(&ulpq->reasm, sctp_event2skb(event)); | |
295 | return; | |
296 | } | |
297 | ||
298 | /* Short circuit just dropping it at the end. */ | |
299 | cevent = sctp_skb2event(pos); | |
300 | ctsn = cevent->tsn; | |
301 | if (TSN_lt(ctsn, tsn)) { | |
302 | __skb_queue_tail(&ulpq->reasm, sctp_event2skb(event)); | |
303 | return; | |
304 | } | |
305 | ||
306 | /* Find the right place in this list. We store them by TSN. */ | |
307 | skb_queue_walk(&ulpq->reasm, pos) { | |
308 | cevent = sctp_skb2event(pos); | |
309 | ctsn = cevent->tsn; | |
310 | ||
311 | if (TSN_lt(tsn, ctsn)) | |
312 | break; | |
313 | } | |
314 | ||
315 | /* Insert before pos. */ | |
43f59c89 | 316 | __skb_queue_before(&ulpq->reasm, pos, sctp_event2skb(event)); |
1da177e4 LT |
317 | |
318 | } | |
319 | ||
320 | /* Helper function to return an event corresponding to the reassembled | |
321 | * datagram. | |
322 | * This routine creates a re-assembled skb given the first and last skb's | |
323 | * as stored in the reassembly queue. The skb's may be non-linear if the sctp | |
324 | * payload was fragmented on the way and ip had to reassemble them. | |
325 | * We add the rest of skb's to the first skb's fraglist. | |
326 | */ | |
b01a2407 EB |
327 | static struct sctp_ulpevent *sctp_make_reassembled_event(struct net *net, |
328 | struct sk_buff_head *queue, struct sk_buff *f_frag, | |
329 | struct sk_buff *l_frag) | |
1da177e4 LT |
330 | { |
331 | struct sk_buff *pos; | |
672e7cca | 332 | struct sk_buff *new = NULL; |
1da177e4 LT |
333 | struct sctp_ulpevent *event; |
334 | struct sk_buff *pnext, *last; | |
335 | struct sk_buff *list = skb_shinfo(f_frag)->frag_list; | |
336 | ||
337 | /* Store the pointer to the 2nd skb */ | |
338 | if (f_frag == l_frag) | |
339 | pos = NULL; | |
340 | else | |
341 | pos = f_frag->next; | |
342 | ||
343 | /* Get the last skb in the f_frag's frag_list if present. */ | |
8d72651d | 344 | for (last = list; list; last = list, list = list->next) |
345 | ; | |
1da177e4 LT |
346 | |
347 | /* Add the list of remaining fragments to the first fragments | |
348 | * frag_list. | |
349 | */ | |
350 | if (last) | |
351 | last->next = pos; | |
d808ad9a YH |
352 | else { |
353 | if (skb_cloned(f_frag)) { | |
354 | /* This is a cloned skb, we can't just modify | |
355 | * the frag_list. We need a new skb to do that. | |
356 | * Instead of calling skb_unshare(), we'll do it | |
357 | * ourselves since we need to delay the free. | |
358 | */ | |
359 | new = skb_copy(f_frag, GFP_ATOMIC); | |
360 | if (!new) | |
361 | return NULL; /* try again later */ | |
362 | ||
363 | sctp_skb_set_owner_r(new, f_frag->sk); | |
364 | ||
365 | skb_shinfo(new)->frag_list = pos; | |
366 | } else | |
367 | skb_shinfo(f_frag)->frag_list = pos; | |
368 | } | |
1da177e4 LT |
369 | |
370 | /* Remove the first fragment from the reassembly queue. */ | |
8728b834 | 371 | __skb_unlink(f_frag, queue); |
672e7cca | 372 | |
d808ad9a YH |
373 | /* if we did unshare, then free the old skb and re-assign */ |
374 | if (new) { | |
375 | kfree_skb(f_frag); | |
376 | f_frag = new; | |
377 | } | |
672e7cca | 378 | |
1da177e4 LT |
379 | while (pos) { |
380 | ||
381 | pnext = pos->next; | |
382 | ||
383 | /* Update the len and data_len fields of the first fragment. */ | |
384 | f_frag->len += pos->len; | |
385 | f_frag->data_len += pos->len; | |
386 | ||
387 | /* Remove the fragment from the reassembly queue. */ | |
8728b834 | 388 | __skb_unlink(pos, queue); |
d808ad9a | 389 | |
1da177e4 LT |
390 | /* Break if we have reached the last fragment. */ |
391 | if (pos == l_frag) | |
392 | break; | |
393 | pos->next = pnext; | |
394 | pos = pnext; | |
3ff50b79 | 395 | } |
1da177e4 LT |
396 | |
397 | event = sctp_skb2event(f_frag); | |
b01a2407 | 398 | SCTP_INC_STATS(net, SCTP_MIB_REASMUSRMSGS); |
1da177e4 LT |
399 | |
400 | return event; | |
401 | } | |
402 | ||
403 | ||
404 | /* Helper function to check if an incoming chunk has filled up the last | |
405 | * missing fragment in a SCTP datagram and return the corresponding event. | |
406 | */ | |
01f2d384 | 407 | static struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_ulpq *ulpq) |
1da177e4 LT |
408 | { |
409 | struct sk_buff *pos; | |
410 | struct sctp_ulpevent *cevent; | |
411 | struct sk_buff *first_frag = NULL; | |
412 | __u32 ctsn, next_tsn; | |
413 | struct sctp_ulpevent *retval = NULL; | |
d49d91d7 VY |
414 | struct sk_buff *pd_first = NULL; |
415 | struct sk_buff *pd_last = NULL; | |
416 | size_t pd_len = 0; | |
417 | struct sctp_association *asoc; | |
418 | u32 pd_point; | |
1da177e4 LT |
419 | |
420 | /* Initialized to 0 just to avoid compiler warning message. Will | |
421 | * never be used with this value. It is referenced only after it | |
422 | * is set when we find the first fragment of a message. | |
423 | */ | |
424 | next_tsn = 0; | |
425 | ||
426 | /* The chunks are held in the reasm queue sorted by TSN. | |
427 | * Walk through the queue sequentially and look for a sequence of | |
428 | * fragmented chunks that complete a datagram. | |
429 | * 'first_frag' and next_tsn are reset when we find a chunk which | |
430 | * is the first fragment of a datagram. Once these 2 fields are set | |
431 | * we expect to find the remaining middle fragments and the last | |
432 | * fragment in order. If not, first_frag is reset to NULL and we | |
433 | * start the next pass when we find another first fragment. | |
d49d91d7 VY |
434 | * |
435 | * There is a potential to do partial delivery if user sets | |
436 | * SCTP_PARTIAL_DELIVERY_POINT option. Lets count some things here | |
437 | * to see if can do PD. | |
1da177e4 LT |
438 | */ |
439 | skb_queue_walk(&ulpq->reasm, pos) { | |
440 | cevent = sctp_skb2event(pos); | |
441 | ctsn = cevent->tsn; | |
442 | ||
443 | switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { | |
444 | case SCTP_DATA_FIRST_FRAG: | |
d49d91d7 VY |
445 | /* If this "FIRST_FRAG" is the first |
446 | * element in the queue, then count it towards | |
447 | * possible PD. | |
448 | */ | |
449 | if (pos == ulpq->reasm.next) { | |
450 | pd_first = pos; | |
451 | pd_last = pos; | |
452 | pd_len = pos->len; | |
453 | } else { | |
454 | pd_first = NULL; | |
455 | pd_last = NULL; | |
456 | pd_len = 0; | |
457 | } | |
458 | ||
1da177e4 LT |
459 | first_frag = pos; |
460 | next_tsn = ctsn + 1; | |
461 | break; | |
462 | ||
463 | case SCTP_DATA_MIDDLE_FRAG: | |
d49d91d7 | 464 | if ((first_frag) && (ctsn == next_tsn)) { |
1da177e4 | 465 | next_tsn++; |
d49d91d7 VY |
466 | if (pd_first) { |
467 | pd_last = pos; | |
468 | pd_len += pos->len; | |
469 | } | |
470 | } else | |
1da177e4 LT |
471 | first_frag = NULL; |
472 | break; | |
473 | ||
474 | case SCTP_DATA_LAST_FRAG: | |
475 | if (first_frag && (ctsn == next_tsn)) | |
476 | goto found; | |
477 | else | |
478 | first_frag = NULL; | |
479 | break; | |
3ff50b79 | 480 | } |
d49d91d7 VY |
481 | } |
482 | ||
483 | asoc = ulpq->asoc; | |
484 | if (pd_first) { | |
485 | /* Make sure we can enter partial deliver. | |
486 | * We can trigger partial delivery only if framgent | |
487 | * interleave is set, or the socket is not already | |
488 | * in partial delivery. | |
489 | */ | |
490 | if (!sctp_sk(asoc->base.sk)->frag_interleave && | |
491 | atomic_read(&sctp_sk(asoc->base.sk)->pd_mode)) | |
492 | goto done; | |
1da177e4 | 493 | |
d49d91d7 VY |
494 | cevent = sctp_skb2event(pd_first); |
495 | pd_point = sctp_sk(asoc->base.sk)->pd_point; | |
496 | if (pd_point && pd_point <= pd_len) { | |
b01a2407 EB |
497 | retval = sctp_make_reassembled_event(sock_net(asoc->base.sk), |
498 | &ulpq->reasm, | |
d49d91d7 VY |
499 | pd_first, |
500 | pd_last); | |
501 | if (retval) | |
502 | sctp_ulpq_set_pd(ulpq); | |
503 | } | |
1da177e4 LT |
504 | } |
505 | done: | |
506 | return retval; | |
507 | found: | |
b01a2407 EB |
508 | retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), |
509 | &ulpq->reasm, first_frag, pos); | |
1da177e4 LT |
510 | if (retval) |
511 | retval->msg_flags |= MSG_EOR; | |
512 | goto done; | |
513 | } | |
514 | ||
515 | /* Retrieve the next set of fragments of a partial message. */ | |
01f2d384 | 516 | static struct sctp_ulpevent *sctp_ulpq_retrieve_partial(struct sctp_ulpq *ulpq) |
1da177e4 LT |
517 | { |
518 | struct sk_buff *pos, *last_frag, *first_frag; | |
519 | struct sctp_ulpevent *cevent; | |
520 | __u32 ctsn, next_tsn; | |
521 | int is_last; | |
522 | struct sctp_ulpevent *retval; | |
523 | ||
524 | /* The chunks are held in the reasm queue sorted by TSN. | |
525 | * Walk through the queue sequentially and look for the first | |
526 | * sequence of fragmented chunks. | |
527 | */ | |
528 | ||
529 | if (skb_queue_empty(&ulpq->reasm)) | |
530 | return NULL; | |
531 | ||
532 | last_frag = first_frag = NULL; | |
533 | retval = NULL; | |
534 | next_tsn = 0; | |
535 | is_last = 0; | |
536 | ||
537 | skb_queue_walk(&ulpq->reasm, pos) { | |
538 | cevent = sctp_skb2event(pos); | |
539 | ctsn = cevent->tsn; | |
540 | ||
541 | switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { | |
d003b41b LR |
542 | case SCTP_DATA_FIRST_FRAG: |
543 | if (!first_frag) | |
544 | return NULL; | |
545 | goto done; | |
1da177e4 LT |
546 | case SCTP_DATA_MIDDLE_FRAG: |
547 | if (!first_frag) { | |
548 | first_frag = pos; | |
549 | next_tsn = ctsn + 1; | |
550 | last_frag = pos; | |
d003b41b | 551 | } else if (next_tsn == ctsn) { |
1da177e4 | 552 | next_tsn++; |
d003b41b LR |
553 | last_frag = pos; |
554 | } else | |
1da177e4 LT |
555 | goto done; |
556 | break; | |
557 | case SCTP_DATA_LAST_FRAG: | |
558 | if (!first_frag) | |
559 | first_frag = pos; | |
560 | else if (ctsn != next_tsn) | |
561 | goto done; | |
562 | last_frag = pos; | |
563 | is_last = 1; | |
564 | goto done; | |
565 | default: | |
566 | return NULL; | |
3ff50b79 | 567 | } |
1da177e4 LT |
568 | } |
569 | ||
570 | /* We have the reassembled event. There is no need to look | |
571 | * further. | |
572 | */ | |
573 | done: | |
b01a2407 EB |
574 | retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), |
575 | &ulpq->reasm, first_frag, last_frag); | |
1da177e4 LT |
576 | if (retval && is_last) |
577 | retval->msg_flags |= MSG_EOR; | |
578 | ||
579 | return retval; | |
580 | } | |
581 | ||
582 | ||
583 | /* Helper function to reassemble chunks. Hold chunks on the reasm queue that | |
584 | * need reassembling. | |
585 | */ | |
586 | static struct sctp_ulpevent *sctp_ulpq_reasm(struct sctp_ulpq *ulpq, | |
587 | struct sctp_ulpevent *event) | |
588 | { | |
589 | struct sctp_ulpevent *retval = NULL; | |
590 | ||
591 | /* Check if this is part of a fragmented message. */ | |
592 | if (SCTP_DATA_NOT_FRAG == (event->msg_flags & SCTP_DATA_FRAG_MASK)) { | |
593 | event->msg_flags |= MSG_EOR; | |
594 | return event; | |
595 | } | |
596 | ||
597 | sctp_ulpq_store_reasm(ulpq, event); | |
598 | if (!ulpq->pd_mode) | |
599 | retval = sctp_ulpq_retrieve_reassembled(ulpq); | |
600 | else { | |
601 | __u32 ctsn, ctsnap; | |
602 | ||
603 | /* Do not even bother unless this is the next tsn to | |
604 | * be delivered. | |
605 | */ | |
606 | ctsn = event->tsn; | |
607 | ctsnap = sctp_tsnmap_get_ctsn(&ulpq->asoc->peer.tsn_map); | |
608 | if (TSN_lte(ctsn, ctsnap)) | |
609 | retval = sctp_ulpq_retrieve_partial(ulpq); | |
610 | } | |
611 | ||
612 | return retval; | |
613 | } | |
614 | ||
615 | /* Retrieve the first part (sequential fragments) for partial delivery. */ | |
01f2d384 | 616 | static struct sctp_ulpevent *sctp_ulpq_retrieve_first(struct sctp_ulpq *ulpq) |
1da177e4 LT |
617 | { |
618 | struct sk_buff *pos, *last_frag, *first_frag; | |
619 | struct sctp_ulpevent *cevent; | |
620 | __u32 ctsn, next_tsn; | |
621 | struct sctp_ulpevent *retval; | |
622 | ||
623 | /* The chunks are held in the reasm queue sorted by TSN. | |
624 | * Walk through the queue sequentially and look for a sequence of | |
625 | * fragmented chunks that start a datagram. | |
626 | */ | |
627 | ||
628 | if (skb_queue_empty(&ulpq->reasm)) | |
629 | return NULL; | |
630 | ||
631 | last_frag = first_frag = NULL; | |
632 | retval = NULL; | |
633 | next_tsn = 0; | |
634 | ||
635 | skb_queue_walk(&ulpq->reasm, pos) { | |
636 | cevent = sctp_skb2event(pos); | |
637 | ctsn = cevent->tsn; | |
638 | ||
639 | switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { | |
640 | case SCTP_DATA_FIRST_FRAG: | |
641 | if (!first_frag) { | |
642 | first_frag = pos; | |
643 | next_tsn = ctsn + 1; | |
644 | last_frag = pos; | |
645 | } else | |
646 | goto done; | |
647 | break; | |
648 | ||
649 | case SCTP_DATA_MIDDLE_FRAG: | |
650 | if (!first_frag) | |
651 | return NULL; | |
652 | if (ctsn == next_tsn) { | |
653 | next_tsn++; | |
654 | last_frag = pos; | |
655 | } else | |
656 | goto done; | |
657 | break; | |
d003b41b LR |
658 | |
659 | case SCTP_DATA_LAST_FRAG: | |
660 | if (!first_frag) | |
661 | return NULL; | |
662 | else | |
663 | goto done; | |
664 | break; | |
665 | ||
1da177e4 LT |
666 | default: |
667 | return NULL; | |
3ff50b79 | 668 | } |
1da177e4 LT |
669 | } |
670 | ||
671 | /* We have the reassembled event. There is no need to look | |
672 | * further. | |
673 | */ | |
674 | done: | |
b01a2407 EB |
675 | retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), |
676 | &ulpq->reasm, first_frag, last_frag); | |
1da177e4 LT |
677 | return retval; |
678 | } | |
679 | ||
ea2dfb37 VY |
680 | /* |
681 | * Flush out stale fragments from the reassembly queue when processing | |
682 | * a Forward TSN. | |
683 | * | |
684 | * RFC 3758, Section 3.6 | |
685 | * | |
686 | * After receiving and processing a FORWARD TSN, the data receiver MUST | |
687 | * take cautions in updating its re-assembly queue. The receiver MUST | |
688 | * remove any partially reassembled message, which is still missing one | |
689 | * or more TSNs earlier than or equal to the new cumulative TSN point. | |
690 | * In the event that the receiver has invoked the partial delivery API, | |
691 | * a notification SHOULD also be generated to inform the upper layer API | |
692 | * that the message being partially delivered will NOT be completed. | |
693 | */ | |
694 | void sctp_ulpq_reasm_flushtsn(struct sctp_ulpq *ulpq, __u32 fwd_tsn) | |
695 | { | |
696 | struct sk_buff *pos, *tmp; | |
697 | struct sctp_ulpevent *event; | |
698 | __u32 tsn; | |
699 | ||
700 | if (skb_queue_empty(&ulpq->reasm)) | |
701 | return; | |
702 | ||
703 | skb_queue_walk_safe(&ulpq->reasm, pos, tmp) { | |
704 | event = sctp_skb2event(pos); | |
705 | tsn = event->tsn; | |
706 | ||
707 | /* Since the entire message must be abandoned by the | |
708 | * sender (item A3 in Section 3.5, RFC 3758), we can | |
709 | * free all fragments on the list that are less then | |
710 | * or equal to ctsn_point | |
711 | */ | |
712 | if (TSN_lte(tsn, fwd_tsn)) { | |
713 | __skb_unlink(pos, &ulpq->reasm); | |
714 | sctp_ulpevent_free(event); | |
715 | } else | |
716 | break; | |
717 | } | |
718 | } | |
719 | ||
ef5d4cf2 VY |
720 | /* |
721 | * Drain the reassembly queue. If we just cleared parted delivery, it | |
722 | * is possible that the reassembly queue will contain already reassembled | |
723 | * messages. Retrieve any such messages and give them to the user. | |
724 | */ | |
725 | static void sctp_ulpq_reasm_drain(struct sctp_ulpq *ulpq) | |
726 | { | |
727 | struct sctp_ulpevent *event = NULL; | |
728 | struct sk_buff_head temp; | |
729 | ||
730 | if (skb_queue_empty(&ulpq->reasm)) | |
731 | return; | |
732 | ||
733 | while ((event = sctp_ulpq_retrieve_reassembled(ulpq)) != NULL) { | |
734 | /* Do ordering if needed. */ | |
cb3f837b | 735 | if ((event) && (event->msg_flags & MSG_EOR)) { |
ef5d4cf2 VY |
736 | skb_queue_head_init(&temp); |
737 | __skb_queue_tail(&temp, sctp_event2skb(event)); | |
738 | ||
739 | event = sctp_ulpq_order(ulpq, event); | |
740 | } | |
741 | ||
742 | /* Send event to the ULP. 'event' is the | |
743 | * sctp_ulpevent for very first SKB on the temp' list. | |
744 | */ | |
745 | if (event) | |
746 | sctp_ulpq_tail_event(ulpq, event); | |
747 | } | |
748 | } | |
749 | ||
750 | ||
1da177e4 LT |
751 | /* Helper function to gather skbs that have possibly become |
752 | * ordered by an an incoming chunk. | |
753 | */ | |
01f2d384 | 754 | static void sctp_ulpq_retrieve_ordered(struct sctp_ulpq *ulpq, |
1da177e4 LT |
755 | struct sctp_ulpevent *event) |
756 | { | |
8728b834 | 757 | struct sk_buff_head *event_list; |
1da177e4 LT |
758 | struct sk_buff *pos, *tmp; |
759 | struct sctp_ulpevent *cevent; | |
760 | struct sctp_stream *in; | |
efea2c6b | 761 | __u16 sid, csid, cssn; |
1da177e4 LT |
762 | |
763 | sid = event->stream; | |
1da177e4 LT |
764 | in = &ulpq->asoc->ssnmap->in; |
765 | ||
8728b834 DM |
766 | event_list = (struct sk_buff_head *) sctp_event2skb(event)->prev; |
767 | ||
1da177e4 LT |
768 | /* We are holding the chunks by stream, by SSN. */ |
769 | sctp_skb_for_each(pos, &ulpq->lobby, tmp) { | |
770 | cevent = (struct sctp_ulpevent *) pos->cb; | |
771 | csid = cevent->stream; | |
772 | cssn = cevent->ssn; | |
773 | ||
774 | /* Have we gone too far? */ | |
775 | if (csid > sid) | |
776 | break; | |
777 | ||
778 | /* Have we not gone far enough? */ | |
779 | if (csid < sid) | |
780 | continue; | |
781 | ||
782 | if (cssn != sctp_ssn_peek(in, sid)) | |
783 | break; | |
784 | ||
785 | /* Found it, so mark in the ssnmap. */ | |
786 | sctp_ssn_next(in, sid); | |
787 | ||
8728b834 | 788 | __skb_unlink(pos, &ulpq->lobby); |
1da177e4 LT |
789 | |
790 | /* Attach all gathered skbs to the event. */ | |
8728b834 | 791 | __skb_queue_tail(event_list, pos); |
1da177e4 LT |
792 | } |
793 | } | |
794 | ||
795 | /* Helper function to store chunks needing ordering. */ | |
01f2d384 | 796 | static void sctp_ulpq_store_ordered(struct sctp_ulpq *ulpq, |
1da177e4 LT |
797 | struct sctp_ulpevent *event) |
798 | { | |
799 | struct sk_buff *pos; | |
800 | struct sctp_ulpevent *cevent; | |
801 | __u16 sid, csid; | |
802 | __u16 ssn, cssn; | |
803 | ||
804 | pos = skb_peek_tail(&ulpq->lobby); | |
805 | if (!pos) { | |
806 | __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); | |
807 | return; | |
808 | } | |
809 | ||
810 | sid = event->stream; | |
811 | ssn = event->ssn; | |
d808ad9a | 812 | |
1da177e4 LT |
813 | cevent = (struct sctp_ulpevent *) pos->cb; |
814 | csid = cevent->stream; | |
815 | cssn = cevent->ssn; | |
816 | if (sid > csid) { | |
817 | __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); | |
818 | return; | |
819 | } | |
820 | ||
821 | if ((sid == csid) && SSN_lt(cssn, ssn)) { | |
822 | __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); | |
823 | return; | |
824 | } | |
825 | ||
826 | /* Find the right place in this list. We store them by | |
827 | * stream ID and then by SSN. | |
828 | */ | |
829 | skb_queue_walk(&ulpq->lobby, pos) { | |
830 | cevent = (struct sctp_ulpevent *) pos->cb; | |
831 | csid = cevent->stream; | |
832 | cssn = cevent->ssn; | |
833 | ||
834 | if (csid > sid) | |
835 | break; | |
836 | if (csid == sid && SSN_lt(ssn, cssn)) | |
837 | break; | |
838 | } | |
839 | ||
840 | ||
841 | /* Insert before pos. */ | |
43f59c89 | 842 | __skb_queue_before(&ulpq->lobby, pos, sctp_event2skb(event)); |
1da177e4 LT |
843 | } |
844 | ||
845 | static struct sctp_ulpevent *sctp_ulpq_order(struct sctp_ulpq *ulpq, | |
8728b834 | 846 | struct sctp_ulpevent *event) |
1da177e4 LT |
847 | { |
848 | __u16 sid, ssn; | |
849 | struct sctp_stream *in; | |
850 | ||
851 | /* Check if this message needs ordering. */ | |
852 | if (SCTP_DATA_UNORDERED & event->msg_flags) | |
853 | return event; | |
854 | ||
855 | /* Note: The stream ID must be verified before this routine. */ | |
856 | sid = event->stream; | |
857 | ssn = event->ssn; | |
858 | in = &ulpq->asoc->ssnmap->in; | |
859 | ||
860 | /* Is this the expected SSN for this stream ID? */ | |
861 | if (ssn != sctp_ssn_peek(in, sid)) { | |
862 | /* We've received something out of order, so find where it | |
863 | * needs to be placed. We order by stream and then by SSN. | |
864 | */ | |
865 | sctp_ulpq_store_ordered(ulpq, event); | |
866 | return NULL; | |
867 | } | |
868 | ||
869 | /* Mark that the next chunk has been found. */ | |
870 | sctp_ssn_next(in, sid); | |
871 | ||
872 | /* Go find any other chunks that were waiting for | |
873 | * ordering. | |
874 | */ | |
875 | sctp_ulpq_retrieve_ordered(ulpq, event); | |
876 | ||
877 | return event; | |
878 | } | |
879 | ||
880 | /* Helper function to gather skbs that have possibly become | |
881 | * ordered by forward tsn skipping their dependencies. | |
882 | */ | |
01f2d384 | 883 | static void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq, __u16 sid) |
1da177e4 LT |
884 | { |
885 | struct sk_buff *pos, *tmp; | |
886 | struct sctp_ulpevent *cevent; | |
8728b834 | 887 | struct sctp_ulpevent *event; |
1da177e4 LT |
888 | struct sctp_stream *in; |
889 | struct sk_buff_head temp; | |
c068be54 | 890 | struct sk_buff_head *lobby = &ulpq->lobby; |
1da177e4 LT |
891 | __u16 csid, cssn; |
892 | ||
893 | in = &ulpq->asoc->ssnmap->in; | |
894 | ||
895 | /* We are holding the chunks by stream, by SSN. */ | |
8728b834 DM |
896 | skb_queue_head_init(&temp); |
897 | event = NULL; | |
c068be54 | 898 | sctp_skb_for_each(pos, lobby, tmp) { |
1da177e4 LT |
899 | cevent = (struct sctp_ulpevent *) pos->cb; |
900 | csid = cevent->stream; | |
901 | cssn = cevent->ssn; | |
902 | ||
ea2dfb37 VY |
903 | /* Have we gone too far? */ |
904 | if (csid > sid) | |
1da177e4 LT |
905 | break; |
906 | ||
ea2dfb37 VY |
907 | /* Have we not gone far enough? */ |
908 | if (csid < sid) | |
909 | continue; | |
910 | ||
911 | /* see if this ssn has been marked by skipping */ | |
c068be54 | 912 | if (!SSN_lt(cssn, sctp_ssn_peek(in, csid))) |
ea2dfb37 | 913 | break; |
1da177e4 | 914 | |
c068be54 | 915 | __skb_unlink(pos, lobby); |
ea2dfb37 | 916 | if (!event) |
1da177e4 LT |
917 | /* Create a temporary list to collect chunks on. */ |
918 | event = sctp_skb2event(pos); | |
ea2dfb37 VY |
919 | |
920 | /* Attach all gathered skbs to the event. */ | |
921 | __skb_queue_tail(&temp, pos); | |
1da177e4 LT |
922 | } |
923 | ||
c068be54 VY |
924 | /* If we didn't reap any data, see if the next expected SSN |
925 | * is next on the queue and if so, use that. | |
926 | */ | |
927 | if (event == NULL && pos != (struct sk_buff *)lobby) { | |
928 | cevent = (struct sctp_ulpevent *) pos->cb; | |
929 | csid = cevent->stream; | |
930 | cssn = cevent->ssn; | |
931 | ||
932 | if (csid == sid && cssn == sctp_ssn_peek(in, csid)) { | |
933 | sctp_ssn_next(in, csid); | |
934 | __skb_unlink(pos, lobby); | |
935 | __skb_queue_tail(&temp, pos); | |
936 | event = sctp_skb2event(pos); | |
937 | } | |
938 | } | |
939 | ||
8728b834 DM |
940 | /* Send event to the ULP. 'event' is the sctp_ulpevent for |
941 | * very first SKB on the 'temp' list. | |
942 | */ | |
ea2dfb37 VY |
943 | if (event) { |
944 | /* see if we have more ordered that we can deliver */ | |
945 | sctp_ulpq_retrieve_ordered(ulpq, event); | |
1da177e4 | 946 | sctp_ulpq_tail_event(ulpq, event); |
ea2dfb37 | 947 | } |
1da177e4 LT |
948 | } |
949 | ||
ea2dfb37 VY |
950 | /* Skip over an SSN. This is used during the processing of |
951 | * Forwared TSN chunk to skip over the abandoned ordered data | |
952 | */ | |
1da177e4 LT |
953 | void sctp_ulpq_skip(struct sctp_ulpq *ulpq, __u16 sid, __u16 ssn) |
954 | { | |
955 | struct sctp_stream *in; | |
956 | ||
957 | /* Note: The stream ID must be verified before this routine. */ | |
958 | in = &ulpq->asoc->ssnmap->in; | |
959 | ||
960 | /* Is this an old SSN? If so ignore. */ | |
961 | if (SSN_lt(ssn, sctp_ssn_peek(in, sid))) | |
962 | return; | |
963 | ||
964 | /* Mark that we are no longer expecting this SSN or lower. */ | |
965 | sctp_ssn_skip(in, sid, ssn); | |
966 | ||
967 | /* Go find any other chunks that were waiting for | |
d808ad9a | 968 | * ordering and deliver them if needed. |
1da177e4 | 969 | */ |
ea2dfb37 | 970 | sctp_ulpq_reap_ordered(ulpq, sid); |
1da177e4 LT |
971 | } |
972 | ||
16d14ef9 PE |
973 | static __u16 sctp_ulpq_renege_list(struct sctp_ulpq *ulpq, |
974 | struct sk_buff_head *list, __u16 needed) | |
1da177e4 LT |
975 | { |
976 | __u16 freed = 0; | |
95ac7b85 LR |
977 | __u32 tsn, last_tsn; |
978 | struct sk_buff *skb, *flist, *last; | |
1da177e4 LT |
979 | struct sctp_ulpevent *event; |
980 | struct sctp_tsnmap *tsnmap; | |
981 | ||
982 | tsnmap = &ulpq->asoc->peer.tsn_map; | |
983 | ||
e67f85ec | 984 | while ((skb = skb_peek_tail(list)) != NULL) { |
1da177e4 LT |
985 | event = sctp_skb2event(skb); |
986 | tsn = event->tsn; | |
987 | ||
e67f85ec LR |
988 | /* Don't renege below the Cumulative TSN ACK Point. */ |
989 | if (TSN_lte(tsn, sctp_tsnmap_get_ctsn(tsnmap))) | |
990 | break; | |
991 | ||
95ac7b85 LR |
992 | /* Events in ordering queue may have multiple fragments |
993 | * corresponding to additional TSNs. Sum the total | |
994 | * freed space; find the last TSN. | |
995 | */ | |
e67f85ec | 996 | freed += skb_headlen(skb); |
95ac7b85 LR |
997 | flist = skb_shinfo(skb)->frag_list; |
998 | for (last = flist; flist; flist = flist->next) { | |
999 | last = flist; | |
1000 | freed += skb_headlen(last); | |
1001 | } | |
1002 | if (last) | |
1003 | last_tsn = sctp_skb2event(last)->tsn; | |
1004 | else | |
1005 | last_tsn = tsn; | |
1006 | ||
1007 | /* Unlink the event, then renege all applicable TSNs. */ | |
1008 | __skb_unlink(skb, list); | |
1da177e4 | 1009 | sctp_ulpevent_free(event); |
95ac7b85 LR |
1010 | while (TSN_lte(tsn, last_tsn)) { |
1011 | sctp_tsnmap_renege(tsnmap, tsn); | |
1012 | tsn++; | |
1013 | } | |
1da177e4 LT |
1014 | if (freed >= needed) |
1015 | return freed; | |
1016 | } | |
1017 | ||
1018 | return freed; | |
1019 | } | |
1020 | ||
16d14ef9 PE |
1021 | /* Renege 'needed' bytes from the ordering queue. */ |
1022 | static __u16 sctp_ulpq_renege_order(struct sctp_ulpq *ulpq, __u16 needed) | |
1023 | { | |
1024 | return sctp_ulpq_renege_list(ulpq, &ulpq->lobby, needed); | |
1025 | } | |
1026 | ||
1da177e4 LT |
1027 | /* Renege 'needed' bytes from the reassembly queue. */ |
1028 | static __u16 sctp_ulpq_renege_frags(struct sctp_ulpq *ulpq, __u16 needed) | |
1029 | { | |
16d14ef9 | 1030 | return sctp_ulpq_renege_list(ulpq, &ulpq->reasm, needed); |
1da177e4 LT |
1031 | } |
1032 | ||
1033 | /* Partial deliver the first message as there is pressure on rwnd. */ | |
1034 | void sctp_ulpq_partial_delivery(struct sctp_ulpq *ulpq, | |
dd0fc66f | 1035 | gfp_t gfp) |
1da177e4 LT |
1036 | { |
1037 | struct sctp_ulpevent *event; | |
1038 | struct sctp_association *asoc; | |
b6e1331f | 1039 | struct sctp_sock *sp; |
d003b41b LR |
1040 | __u32 ctsn; |
1041 | struct sk_buff *skb; | |
1da177e4 LT |
1042 | |
1043 | asoc = ulpq->asoc; | |
b6e1331f | 1044 | sp = sctp_sk(asoc->base.sk); |
1da177e4 | 1045 | |
b6e1331f | 1046 | /* If the association is already in Partial Delivery mode |
d003b41b | 1047 | * we have nothing to do. |
b6e1331f VY |
1048 | */ |
1049 | if (ulpq->pd_mode) | |
1050 | return; | |
1da177e4 | 1051 | |
d003b41b LR |
1052 | /* Data must be at or below the Cumulative TSN ACK Point to |
1053 | * start partial delivery. | |
1054 | */ | |
1055 | skb = skb_peek(&asoc->ulpq.reasm); | |
1056 | if (skb != NULL) { | |
1057 | ctsn = sctp_skb2event(skb)->tsn; | |
1058 | if (!TSN_lte(ctsn, sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map))) | |
1059 | return; | |
1060 | } | |
1061 | ||
b6e1331f VY |
1062 | /* If the user enabled fragment interleave socket option, |
1063 | * multiple associations can enter partial delivery. | |
1064 | * Otherwise, we can only enter partial delivery if the | |
1065 | * socket is not in partial deliver mode. | |
1066 | */ | |
1067 | if (sp->frag_interleave || atomic_read(&sp->pd_mode) == 0) { | |
1da177e4 LT |
1068 | /* Is partial delivery possible? */ |
1069 | event = sctp_ulpq_retrieve_first(ulpq); | |
1070 | /* Send event to the ULP. */ | |
1071 | if (event) { | |
1072 | sctp_ulpq_tail_event(ulpq, event); | |
d49d91d7 | 1073 | sctp_ulpq_set_pd(ulpq); |
1da177e4 LT |
1074 | return; |
1075 | } | |
1076 | } | |
1077 | } | |
1078 | ||
1079 | /* Renege some packets to make room for an incoming chunk. */ | |
1080 | void sctp_ulpq_renege(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk, | |
dd0fc66f | 1081 | gfp_t gfp) |
1da177e4 LT |
1082 | { |
1083 | struct sctp_association *asoc; | |
1084 | __u16 needed, freed; | |
1085 | ||
1086 | asoc = ulpq->asoc; | |
1087 | ||
1088 | if (chunk) { | |
1089 | needed = ntohs(chunk->chunk_hdr->length); | |
1090 | needed -= sizeof(sctp_data_chunk_t); | |
d808ad9a | 1091 | } else |
1da177e4 LT |
1092 | needed = SCTP_DEFAULT_MAXWINDOW; |
1093 | ||
1094 | freed = 0; | |
1095 | ||
1096 | if (skb_queue_empty(&asoc->base.sk->sk_receive_queue)) { | |
1097 | freed = sctp_ulpq_renege_order(ulpq, needed); | |
1098 | if (freed < needed) { | |
1099 | freed += sctp_ulpq_renege_frags(ulpq, needed - freed); | |
1100 | } | |
1101 | } | |
1102 | /* If able to free enough room, accept this chunk. */ | |
1103 | if (chunk && (freed >= needed)) { | |
d003b41b LR |
1104 | int retval; |
1105 | retval = sctp_ulpq_tail_data(ulpq, chunk, gfp); | |
1106 | /* | |
1107 | * Enter partial delivery if chunk has not been | |
1108 | * delivered; otherwise, drain the reassembly queue. | |
1109 | */ | |
1110 | if (retval <= 0) | |
1111 | sctp_ulpq_partial_delivery(ulpq, gfp); | |
1112 | else if (retval == 1) | |
1113 | sctp_ulpq_reasm_drain(ulpq); | |
1da177e4 LT |
1114 | } |
1115 | ||
3ab224be | 1116 | sk_mem_reclaim(asoc->base.sk); |
1da177e4 LT |
1117 | } |
1118 | ||
1119 | ||
1120 | ||
1121 | /* Notify the application if an association is aborted and in | |
1122 | * partial delivery mode. Send up any pending received messages. | |
1123 | */ | |
dd0fc66f | 1124 | void sctp_ulpq_abort_pd(struct sctp_ulpq *ulpq, gfp_t gfp) |
1da177e4 LT |
1125 | { |
1126 | struct sctp_ulpevent *ev = NULL; | |
1127 | struct sock *sk; | |
1128 | ||
1129 | if (!ulpq->pd_mode) | |
1130 | return; | |
1131 | ||
1132 | sk = ulpq->asoc->base.sk; | |
1133 | if (sctp_ulpevent_type_enabled(SCTP_PARTIAL_DELIVERY_EVENT, | |
1134 | &sctp_sk(sk)->subscribe)) | |
1135 | ev = sctp_ulpevent_make_pdapi(ulpq->asoc, | |
1136 | SCTP_PARTIAL_DELIVERY_ABORTED, | |
1137 | gfp); | |
1138 | if (ev) | |
1139 | __skb_queue_tail(&sk->sk_receive_queue, sctp_event2skb(ev)); | |
1140 | ||
1141 | /* If there is data waiting, send it up the socket now. */ | |
1142 | if (sctp_ulpq_clear_pd(ulpq) || ev) | |
676d2369 | 1143 | sk->sk_data_ready(sk); |
1da177e4 | 1144 | } |