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); | |
13228238 | 63 | skb_queue_head_init(&ulpq->reasm_uo); |
1da177e4 LT |
64 | skb_queue_head_init(&ulpq->lobby); |
65 | ulpq->pd_mode = 0; | |
1da177e4 LT |
66 | |
67 | return ulpq; | |
68 | } | |
69 | ||
70 | ||
71 | /* Flush the reassembly and ordering queues. */ | |
0b58a811 | 72 | void sctp_ulpq_flush(struct sctp_ulpq *ulpq) |
1da177e4 LT |
73 | { |
74 | struct sk_buff *skb; | |
75 | struct sctp_ulpevent *event; | |
76 | ||
77 | while ((skb = __skb_dequeue(&ulpq->lobby)) != NULL) { | |
78 | event = sctp_skb2event(skb); | |
79 | sctp_ulpevent_free(event); | |
80 | } | |
81 | ||
82 | while ((skb = __skb_dequeue(&ulpq->reasm)) != NULL) { | |
83 | event = sctp_skb2event(skb); | |
84 | sctp_ulpevent_free(event); | |
85 | } | |
86 | ||
13228238 XL |
87 | while ((skb = __skb_dequeue(&ulpq->reasm_uo)) != NULL) { |
88 | event = sctp_skb2event(skb); | |
89 | sctp_ulpevent_free(event); | |
90 | } | |
1da177e4 LT |
91 | } |
92 | ||
93 | /* Dispose of a ulpqueue. */ | |
94 | void sctp_ulpq_free(struct sctp_ulpq *ulpq) | |
95 | { | |
96 | sctp_ulpq_flush(ulpq); | |
1da177e4 LT |
97 | } |
98 | ||
99 | /* Process an incoming DATA chunk. */ | |
100 | int sctp_ulpq_tail_data(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk, | |
dd0fc66f | 101 | gfp_t gfp) |
1da177e4 LT |
102 | { |
103 | struct sk_buff_head temp; | |
1da177e4 | 104 | struct sctp_ulpevent *event; |
d003b41b | 105 | int event_eor = 0; |
1da177e4 | 106 | |
1da177e4 LT |
107 | /* Create an event from the incoming chunk. */ |
108 | event = sctp_ulpevent_make_rcvmsg(chunk->asoc, chunk, gfp); | |
109 | if (!event) | |
110 | return -ENOMEM; | |
111 | ||
bd4d627d XL |
112 | event->ssn = ntohs(chunk->subh.data_hdr->ssn); |
113 | event->ppid = chunk->subh.data_hdr->ppid; | |
114 | ||
1da177e4 LT |
115 | /* Do reassembly if needed. */ |
116 | event = sctp_ulpq_reasm(ulpq, event); | |
117 | ||
118 | /* Do ordering if needed. */ | |
cb3f837b | 119 | if ((event) && (event->msg_flags & MSG_EOR)) { |
1da177e4 LT |
120 | /* Create a temporary list to collect chunks on. */ |
121 | skb_queue_head_init(&temp); | |
122 | __skb_queue_tail(&temp, sctp_event2skb(event)); | |
123 | ||
124 | event = sctp_ulpq_order(ulpq, event); | |
125 | } | |
126 | ||
8728b834 DM |
127 | /* Send event to the ULP. 'event' is the sctp_ulpevent for |
128 | * very first SKB on the 'temp' list. | |
129 | */ | |
d003b41b LR |
130 | if (event) { |
131 | event_eor = (event->msg_flags & MSG_EOR) ? 1 : 0; | |
1da177e4 | 132 | sctp_ulpq_tail_event(ulpq, event); |
d003b41b | 133 | } |
1da177e4 | 134 | |
d003b41b | 135 | return event_eor; |
1da177e4 LT |
136 | } |
137 | ||
138 | /* Add a new event for propagation to the ULP. */ | |
139 | /* Clear the partial delivery mode for this socket. Note: This | |
140 | * assumes that no association is currently in partial delivery mode. | |
141 | */ | |
b6e1331f | 142 | int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc) |
1da177e4 LT |
143 | { |
144 | struct sctp_sock *sp = sctp_sk(sk); | |
145 | ||
b6e1331f VY |
146 | if (atomic_dec_and_test(&sp->pd_mode)) { |
147 | /* This means there are no other associations in PD, so | |
148 | * we can go ahead and clear out the lobby in one shot | |
149 | */ | |
150 | if (!skb_queue_empty(&sp->pd_lobby)) { | |
311b2177 MRL |
151 | skb_queue_splice_tail_init(&sp->pd_lobby, |
152 | &sk->sk_receive_queue); | |
b6e1331f VY |
153 | return 1; |
154 | } | |
155 | } else { | |
156 | /* There are other associations in PD, so we only need to | |
157 | * pull stuff out of the lobby that belongs to the | |
158 | * associations that is exiting PD (all of its notifications | |
159 | * are posted here). | |
160 | */ | |
161 | if (!skb_queue_empty(&sp->pd_lobby) && asoc) { | |
162 | struct sk_buff *skb, *tmp; | |
163 | struct sctp_ulpevent *event; | |
164 | ||
165 | sctp_skb_for_each(skb, &sp->pd_lobby, tmp) { | |
166 | event = sctp_skb2event(skb); | |
167 | if (event->asoc == asoc) { | |
168 | __skb_unlink(skb, &sp->pd_lobby); | |
169 | __skb_queue_tail(&sk->sk_receive_queue, | |
170 | skb); | |
171 | } | |
172 | } | |
173 | } | |
1da177e4 | 174 | } |
b6e1331f | 175 | |
1da177e4 LT |
176 | return 0; |
177 | } | |
178 | ||
d49d91d7 VY |
179 | /* Set the pd_mode on the socket and ulpq */ |
180 | static void sctp_ulpq_set_pd(struct sctp_ulpq *ulpq) | |
181 | { | |
182 | struct sctp_sock *sp = sctp_sk(ulpq->asoc->base.sk); | |
183 | ||
184 | atomic_inc(&sp->pd_mode); | |
185 | ulpq->pd_mode = 1; | |
186 | } | |
187 | ||
1da177e4 LT |
188 | /* Clear the pd_mode and restart any pending messages waiting for delivery. */ |
189 | static int sctp_ulpq_clear_pd(struct sctp_ulpq *ulpq) | |
190 | { | |
191 | ulpq->pd_mode = 0; | |
ef5d4cf2 | 192 | sctp_ulpq_reasm_drain(ulpq); |
b6e1331f | 193 | return sctp_clear_pd(ulpq->asoc->base.sk, ulpq->asoc); |
1da177e4 LT |
194 | } |
195 | ||
8728b834 DM |
196 | /* If the SKB of 'event' is on a list, it is the first such member |
197 | * of that list. | |
198 | */ | |
1da177e4 LT |
199 | int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event) |
200 | { | |
201 | struct sock *sk = ulpq->asoc->base.sk; | |
0970f5b3 | 202 | struct sctp_sock *sp = sctp_sk(sk); |
8728b834 DM |
203 | struct sk_buff_head *queue, *skb_list; |
204 | struct sk_buff *skb = sctp_event2skb(event); | |
1da177e4 LT |
205 | int clear_pd = 0; |
206 | ||
8728b834 DM |
207 | skb_list = (struct sk_buff_head *) skb->prev; |
208 | ||
1da177e4 LT |
209 | /* If the socket is just going to throw this away, do not |
210 | * even try to deliver it. | |
211 | */ | |
a0fc6843 XL |
212 | if (sk->sk_shutdown & RCV_SHUTDOWN && |
213 | (sk->sk_shutdown & SEND_SHUTDOWN || | |
214 | !sctp_ulpevent_is_notification(event))) | |
1da177e4 LT |
215 | goto out_free; |
216 | ||
2c8c56e1 | 217 | if (!sctp_ulpevent_is_notification(event)) { |
8465a5fc | 218 | sk_mark_napi_id(sk, skb); |
2c8c56e1 ED |
219 | sk_incoming_cpu_update(sk); |
220 | } | |
1da177e4 | 221 | /* Check if the user wishes to receive this event. */ |
0970f5b3 | 222 | if (!sctp_ulpevent_is_enabled(event, &sp->subscribe)) |
1da177e4 LT |
223 | goto out_free; |
224 | ||
225 | /* If we are in partial delivery mode, post to the lobby until | |
226 | * partial delivery is cleared, unless, of course _this_ is | |
227 | * the association the cause of the partial delivery. | |
228 | */ | |
229 | ||
0970f5b3 | 230 | if (atomic_read(&sp->pd_mode) == 0) { |
1da177e4 | 231 | queue = &sk->sk_receive_queue; |
b6e1331f VY |
232 | } else { |
233 | if (ulpq->pd_mode) { | |
234 | /* If the association is in partial delivery, we | |
235 | * need to finish delivering the partially processed | |
236 | * packet before passing any other data. This is | |
237 | * because we don't truly support stream interleaving. | |
238 | */ | |
239 | if ((event->msg_flags & MSG_NOTIFICATION) || | |
240 | (SCTP_DATA_NOT_FRAG == | |
241 | (event->msg_flags & SCTP_DATA_FRAG_MASK))) | |
0970f5b3 | 242 | queue = &sp->pd_lobby; |
b6e1331f VY |
243 | else { |
244 | clear_pd = event->msg_flags & MSG_EOR; | |
245 | queue = &sk->sk_receive_queue; | |
246 | } | |
247 | } else { | |
248 | /* | |
249 | * If fragment interleave is enabled, we | |
25985edc | 250 | * can queue this to the receive queue instead |
b6e1331f VY |
251 | * of the lobby. |
252 | */ | |
0970f5b3 | 253 | if (sp->frag_interleave) |
b6e1331f VY |
254 | queue = &sk->sk_receive_queue; |
255 | else | |
0970f5b3 | 256 | queue = &sp->pd_lobby; |
1da177e4 | 257 | } |
b6e1331f | 258 | } |
1da177e4 LT |
259 | |
260 | /* If we are harvesting multiple skbs they will be | |
261 | * collected on a list. | |
262 | */ | |
8728b834 | 263 | if (skb_list) |
311b2177 | 264 | skb_queue_splice_tail_init(skb_list, queue); |
1da177e4 | 265 | else |
8728b834 | 266 | __skb_queue_tail(queue, skb); |
1da177e4 LT |
267 | |
268 | /* Did we just complete partial delivery and need to get | |
269 | * rolling again? Move pending data to the receive | |
270 | * queue. | |
271 | */ | |
272 | if (clear_pd) | |
273 | sctp_ulpq_clear_pd(ulpq); | |
274 | ||
0970f5b3 | 275 | if (queue == &sk->sk_receive_queue && !sp->data_ready_signalled) { |
7906b00f MRL |
276 | if (!sock_owned_by_user(sk)) |
277 | sp->data_ready_signalled = 1; | |
0970f5b3 MRL |
278 | sk->sk_data_ready(sk); |
279 | } | |
1da177e4 LT |
280 | return 1; |
281 | ||
282 | out_free: | |
8728b834 DM |
283 | if (skb_list) |
284 | sctp_queue_purge_ulpevents(skb_list); | |
1da177e4 LT |
285 | else |
286 | sctp_ulpevent_free(event); | |
8728b834 | 287 | |
1da177e4 LT |
288 | return 0; |
289 | } | |
290 | ||
291 | /* 2nd Level Abstractions */ | |
292 | ||
293 | /* Helper function to store chunks that need to be reassembled. */ | |
01f2d384 | 294 | static void sctp_ulpq_store_reasm(struct sctp_ulpq *ulpq, |
1da177e4 LT |
295 | struct sctp_ulpevent *event) |
296 | { | |
297 | struct sk_buff *pos; | |
298 | struct sctp_ulpevent *cevent; | |
299 | __u32 tsn, ctsn; | |
300 | ||
301 | tsn = event->tsn; | |
302 | ||
303 | /* See if it belongs at the end. */ | |
304 | pos = skb_peek_tail(&ulpq->reasm); | |
305 | if (!pos) { | |
306 | __skb_queue_tail(&ulpq->reasm, sctp_event2skb(event)); | |
307 | return; | |
308 | } | |
309 | ||
310 | /* Short circuit just dropping it at the end. */ | |
311 | cevent = sctp_skb2event(pos); | |
312 | ctsn = cevent->tsn; | |
313 | if (TSN_lt(ctsn, tsn)) { | |
314 | __skb_queue_tail(&ulpq->reasm, sctp_event2skb(event)); | |
315 | return; | |
316 | } | |
317 | ||
318 | /* Find the right place in this list. We store them by TSN. */ | |
319 | skb_queue_walk(&ulpq->reasm, pos) { | |
320 | cevent = sctp_skb2event(pos); | |
321 | ctsn = cevent->tsn; | |
322 | ||
323 | if (TSN_lt(tsn, ctsn)) | |
324 | break; | |
325 | } | |
326 | ||
327 | /* Insert before pos. */ | |
43f59c89 | 328 | __skb_queue_before(&ulpq->reasm, pos, sctp_event2skb(event)); |
1da177e4 LT |
329 | |
330 | } | |
331 | ||
332 | /* Helper function to return an event corresponding to the reassembled | |
333 | * datagram. | |
334 | * This routine creates a re-assembled skb given the first and last skb's | |
335 | * as stored in the reassembly queue. The skb's may be non-linear if the sctp | |
336 | * payload was fragmented on the way and ip had to reassemble them. | |
337 | * We add the rest of skb's to the first skb's fraglist. | |
338 | */ | |
bd4d627d XL |
339 | struct sctp_ulpevent *sctp_make_reassembled_event(struct net *net, |
340 | struct sk_buff_head *queue, | |
341 | struct sk_buff *f_frag, | |
342 | struct sk_buff *l_frag) | |
1da177e4 LT |
343 | { |
344 | struct sk_buff *pos; | |
672e7cca | 345 | struct sk_buff *new = NULL; |
1da177e4 LT |
346 | struct sctp_ulpevent *event; |
347 | struct sk_buff *pnext, *last; | |
348 | struct sk_buff *list = skb_shinfo(f_frag)->frag_list; | |
349 | ||
350 | /* Store the pointer to the 2nd skb */ | |
351 | if (f_frag == l_frag) | |
352 | pos = NULL; | |
353 | else | |
354 | pos = f_frag->next; | |
355 | ||
356 | /* Get the last skb in the f_frag's frag_list if present. */ | |
8d72651d | 357 | for (last = list; list; last = list, list = list->next) |
358 | ; | |
1da177e4 LT |
359 | |
360 | /* Add the list of remaining fragments to the first fragments | |
361 | * frag_list. | |
362 | */ | |
363 | if (last) | |
364 | last->next = pos; | |
d808ad9a YH |
365 | else { |
366 | if (skb_cloned(f_frag)) { | |
367 | /* This is a cloned skb, we can't just modify | |
368 | * the frag_list. We need a new skb to do that. | |
369 | * Instead of calling skb_unshare(), we'll do it | |
370 | * ourselves since we need to delay the free. | |
371 | */ | |
372 | new = skb_copy(f_frag, GFP_ATOMIC); | |
373 | if (!new) | |
374 | return NULL; /* try again later */ | |
375 | ||
376 | sctp_skb_set_owner_r(new, f_frag->sk); | |
377 | ||
378 | skb_shinfo(new)->frag_list = pos; | |
379 | } else | |
380 | skb_shinfo(f_frag)->frag_list = pos; | |
381 | } | |
1da177e4 LT |
382 | |
383 | /* Remove the first fragment from the reassembly queue. */ | |
8728b834 | 384 | __skb_unlink(f_frag, queue); |
672e7cca | 385 | |
d808ad9a YH |
386 | /* if we did unshare, then free the old skb and re-assign */ |
387 | if (new) { | |
388 | kfree_skb(f_frag); | |
389 | f_frag = new; | |
390 | } | |
672e7cca | 391 | |
1da177e4 LT |
392 | while (pos) { |
393 | ||
394 | pnext = pos->next; | |
395 | ||
396 | /* Update the len and data_len fields of the first fragment. */ | |
397 | f_frag->len += pos->len; | |
398 | f_frag->data_len += pos->len; | |
399 | ||
400 | /* Remove the fragment from the reassembly queue. */ | |
8728b834 | 401 | __skb_unlink(pos, queue); |
d808ad9a | 402 | |
1da177e4 LT |
403 | /* Break if we have reached the last fragment. */ |
404 | if (pos == l_frag) | |
405 | break; | |
406 | pos->next = pnext; | |
407 | pos = pnext; | |
3ff50b79 | 408 | } |
1da177e4 LT |
409 | |
410 | event = sctp_skb2event(f_frag); | |
b01a2407 | 411 | SCTP_INC_STATS(net, SCTP_MIB_REASMUSRMSGS); |
1da177e4 LT |
412 | |
413 | return event; | |
414 | } | |
415 | ||
416 | ||
417 | /* Helper function to check if an incoming chunk has filled up the last | |
418 | * missing fragment in a SCTP datagram and return the corresponding event. | |
419 | */ | |
01f2d384 | 420 | static struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_ulpq *ulpq) |
1da177e4 LT |
421 | { |
422 | struct sk_buff *pos; | |
423 | struct sctp_ulpevent *cevent; | |
424 | struct sk_buff *first_frag = NULL; | |
425 | __u32 ctsn, next_tsn; | |
426 | struct sctp_ulpevent *retval = NULL; | |
d49d91d7 VY |
427 | struct sk_buff *pd_first = NULL; |
428 | struct sk_buff *pd_last = NULL; | |
429 | size_t pd_len = 0; | |
430 | struct sctp_association *asoc; | |
431 | u32 pd_point; | |
1da177e4 LT |
432 | |
433 | /* Initialized to 0 just to avoid compiler warning message. Will | |
434 | * never be used with this value. It is referenced only after it | |
435 | * is set when we find the first fragment of a message. | |
436 | */ | |
437 | next_tsn = 0; | |
438 | ||
439 | /* The chunks are held in the reasm queue sorted by TSN. | |
440 | * Walk through the queue sequentially and look for a sequence of | |
441 | * fragmented chunks that complete a datagram. | |
442 | * 'first_frag' and next_tsn are reset when we find a chunk which | |
443 | * is the first fragment of a datagram. Once these 2 fields are set | |
444 | * we expect to find the remaining middle fragments and the last | |
445 | * fragment in order. If not, first_frag is reset to NULL and we | |
446 | * start the next pass when we find another first fragment. | |
d49d91d7 VY |
447 | * |
448 | * There is a potential to do partial delivery if user sets | |
449 | * SCTP_PARTIAL_DELIVERY_POINT option. Lets count some things here | |
450 | * to see if can do PD. | |
1da177e4 LT |
451 | */ |
452 | skb_queue_walk(&ulpq->reasm, pos) { | |
453 | cevent = sctp_skb2event(pos); | |
454 | ctsn = cevent->tsn; | |
455 | ||
456 | switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { | |
457 | case SCTP_DATA_FIRST_FRAG: | |
d49d91d7 VY |
458 | /* If this "FIRST_FRAG" is the first |
459 | * element in the queue, then count it towards | |
460 | * possible PD. | |
461 | */ | |
462 | if (pos == ulpq->reasm.next) { | |
463 | pd_first = pos; | |
464 | pd_last = pos; | |
465 | pd_len = pos->len; | |
466 | } else { | |
467 | pd_first = NULL; | |
468 | pd_last = NULL; | |
469 | pd_len = 0; | |
470 | } | |
471 | ||
1da177e4 LT |
472 | first_frag = pos; |
473 | next_tsn = ctsn + 1; | |
474 | break; | |
475 | ||
476 | case SCTP_DATA_MIDDLE_FRAG: | |
d49d91d7 | 477 | if ((first_frag) && (ctsn == next_tsn)) { |
1da177e4 | 478 | next_tsn++; |
d49d91d7 VY |
479 | if (pd_first) { |
480 | pd_last = pos; | |
481 | pd_len += pos->len; | |
482 | } | |
483 | } else | |
1da177e4 LT |
484 | first_frag = NULL; |
485 | break; | |
486 | ||
487 | case SCTP_DATA_LAST_FRAG: | |
488 | if (first_frag && (ctsn == next_tsn)) | |
489 | goto found; | |
490 | else | |
491 | first_frag = NULL; | |
492 | break; | |
3ff50b79 | 493 | } |
d49d91d7 VY |
494 | } |
495 | ||
496 | asoc = ulpq->asoc; | |
497 | if (pd_first) { | |
498 | /* Make sure we can enter partial deliver. | |
499 | * We can trigger partial delivery only if framgent | |
500 | * interleave is set, or the socket is not already | |
501 | * in partial delivery. | |
502 | */ | |
503 | if (!sctp_sk(asoc->base.sk)->frag_interleave && | |
504 | atomic_read(&sctp_sk(asoc->base.sk)->pd_mode)) | |
505 | goto done; | |
1da177e4 | 506 | |
d49d91d7 VY |
507 | cevent = sctp_skb2event(pd_first); |
508 | pd_point = sctp_sk(asoc->base.sk)->pd_point; | |
509 | if (pd_point && pd_point <= pd_len) { | |
b01a2407 EB |
510 | retval = sctp_make_reassembled_event(sock_net(asoc->base.sk), |
511 | &ulpq->reasm, | |
d49d91d7 VY |
512 | pd_first, |
513 | pd_last); | |
514 | if (retval) | |
515 | sctp_ulpq_set_pd(ulpq); | |
516 | } | |
1da177e4 LT |
517 | } |
518 | done: | |
519 | return retval; | |
520 | found: | |
b01a2407 EB |
521 | retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), |
522 | &ulpq->reasm, first_frag, pos); | |
1da177e4 LT |
523 | if (retval) |
524 | retval->msg_flags |= MSG_EOR; | |
525 | goto done; | |
526 | } | |
527 | ||
528 | /* Retrieve the next set of fragments of a partial message. */ | |
01f2d384 | 529 | static struct sctp_ulpevent *sctp_ulpq_retrieve_partial(struct sctp_ulpq *ulpq) |
1da177e4 LT |
530 | { |
531 | struct sk_buff *pos, *last_frag, *first_frag; | |
532 | struct sctp_ulpevent *cevent; | |
533 | __u32 ctsn, next_tsn; | |
534 | int is_last; | |
535 | struct sctp_ulpevent *retval; | |
536 | ||
537 | /* The chunks are held in the reasm queue sorted by TSN. | |
538 | * Walk through the queue sequentially and look for the first | |
539 | * sequence of fragmented chunks. | |
540 | */ | |
541 | ||
542 | if (skb_queue_empty(&ulpq->reasm)) | |
543 | return NULL; | |
544 | ||
545 | last_frag = first_frag = NULL; | |
546 | retval = NULL; | |
547 | next_tsn = 0; | |
548 | is_last = 0; | |
549 | ||
550 | skb_queue_walk(&ulpq->reasm, pos) { | |
551 | cevent = sctp_skb2event(pos); | |
552 | ctsn = cevent->tsn; | |
553 | ||
554 | switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { | |
d003b41b LR |
555 | case SCTP_DATA_FIRST_FRAG: |
556 | if (!first_frag) | |
557 | return NULL; | |
558 | goto done; | |
1da177e4 LT |
559 | case SCTP_DATA_MIDDLE_FRAG: |
560 | if (!first_frag) { | |
561 | first_frag = pos; | |
562 | next_tsn = ctsn + 1; | |
563 | last_frag = pos; | |
d003b41b | 564 | } else if (next_tsn == ctsn) { |
1da177e4 | 565 | next_tsn++; |
d003b41b LR |
566 | last_frag = pos; |
567 | } else | |
1da177e4 LT |
568 | goto done; |
569 | break; | |
570 | case SCTP_DATA_LAST_FRAG: | |
571 | if (!first_frag) | |
572 | first_frag = pos; | |
573 | else if (ctsn != next_tsn) | |
574 | goto done; | |
575 | last_frag = pos; | |
576 | is_last = 1; | |
577 | goto done; | |
578 | default: | |
579 | return NULL; | |
3ff50b79 | 580 | } |
1da177e4 LT |
581 | } |
582 | ||
583 | /* We have the reassembled event. There is no need to look | |
584 | * further. | |
585 | */ | |
586 | done: | |
b01a2407 EB |
587 | retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), |
588 | &ulpq->reasm, first_frag, last_frag); | |
1da177e4 LT |
589 | if (retval && is_last) |
590 | retval->msg_flags |= MSG_EOR; | |
591 | ||
592 | return retval; | |
593 | } | |
594 | ||
595 | ||
596 | /* Helper function to reassemble chunks. Hold chunks on the reasm queue that | |
597 | * need reassembling. | |
598 | */ | |
599 | static struct sctp_ulpevent *sctp_ulpq_reasm(struct sctp_ulpq *ulpq, | |
600 | struct sctp_ulpevent *event) | |
601 | { | |
602 | struct sctp_ulpevent *retval = NULL; | |
603 | ||
604 | /* Check if this is part of a fragmented message. */ | |
605 | if (SCTP_DATA_NOT_FRAG == (event->msg_flags & SCTP_DATA_FRAG_MASK)) { | |
606 | event->msg_flags |= MSG_EOR; | |
607 | return event; | |
608 | } | |
609 | ||
610 | sctp_ulpq_store_reasm(ulpq, event); | |
611 | if (!ulpq->pd_mode) | |
612 | retval = sctp_ulpq_retrieve_reassembled(ulpq); | |
613 | else { | |
614 | __u32 ctsn, ctsnap; | |
615 | ||
616 | /* Do not even bother unless this is the next tsn to | |
617 | * be delivered. | |
618 | */ | |
619 | ctsn = event->tsn; | |
620 | ctsnap = sctp_tsnmap_get_ctsn(&ulpq->asoc->peer.tsn_map); | |
621 | if (TSN_lte(ctsn, ctsnap)) | |
622 | retval = sctp_ulpq_retrieve_partial(ulpq); | |
623 | } | |
624 | ||
625 | return retval; | |
626 | } | |
627 | ||
628 | /* Retrieve the first part (sequential fragments) for partial delivery. */ | |
01f2d384 | 629 | static struct sctp_ulpevent *sctp_ulpq_retrieve_first(struct sctp_ulpq *ulpq) |
1da177e4 LT |
630 | { |
631 | struct sk_buff *pos, *last_frag, *first_frag; | |
632 | struct sctp_ulpevent *cevent; | |
633 | __u32 ctsn, next_tsn; | |
634 | struct sctp_ulpevent *retval; | |
635 | ||
636 | /* The chunks are held in the reasm queue sorted by TSN. | |
637 | * Walk through the queue sequentially and look for a sequence of | |
638 | * fragmented chunks that start a datagram. | |
639 | */ | |
640 | ||
641 | if (skb_queue_empty(&ulpq->reasm)) | |
642 | return NULL; | |
643 | ||
644 | last_frag = first_frag = NULL; | |
645 | retval = NULL; | |
646 | next_tsn = 0; | |
647 | ||
648 | skb_queue_walk(&ulpq->reasm, pos) { | |
649 | cevent = sctp_skb2event(pos); | |
650 | ctsn = cevent->tsn; | |
651 | ||
652 | switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { | |
653 | case SCTP_DATA_FIRST_FRAG: | |
654 | if (!first_frag) { | |
655 | first_frag = pos; | |
656 | next_tsn = ctsn + 1; | |
657 | last_frag = pos; | |
658 | } else | |
659 | goto done; | |
660 | break; | |
661 | ||
662 | case SCTP_DATA_MIDDLE_FRAG: | |
663 | if (!first_frag) | |
664 | return NULL; | |
665 | if (ctsn == next_tsn) { | |
666 | next_tsn++; | |
667 | last_frag = pos; | |
668 | } else | |
669 | goto done; | |
670 | break; | |
d003b41b LR |
671 | |
672 | case SCTP_DATA_LAST_FRAG: | |
673 | if (!first_frag) | |
674 | return NULL; | |
675 | else | |
676 | goto done; | |
677 | break; | |
678 | ||
1da177e4 LT |
679 | default: |
680 | return NULL; | |
3ff50b79 | 681 | } |
1da177e4 LT |
682 | } |
683 | ||
684 | /* We have the reassembled event. There is no need to look | |
685 | * further. | |
686 | */ | |
687 | done: | |
b01a2407 EB |
688 | retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), |
689 | &ulpq->reasm, first_frag, last_frag); | |
1da177e4 LT |
690 | return retval; |
691 | } | |
692 | ||
ea2dfb37 VY |
693 | /* |
694 | * Flush out stale fragments from the reassembly queue when processing | |
695 | * a Forward TSN. | |
696 | * | |
697 | * RFC 3758, Section 3.6 | |
698 | * | |
699 | * After receiving and processing a FORWARD TSN, the data receiver MUST | |
700 | * take cautions in updating its re-assembly queue. The receiver MUST | |
701 | * remove any partially reassembled message, which is still missing one | |
702 | * or more TSNs earlier than or equal to the new cumulative TSN point. | |
703 | * In the event that the receiver has invoked the partial delivery API, | |
704 | * a notification SHOULD also be generated to inform the upper layer API | |
705 | * that the message being partially delivered will NOT be completed. | |
706 | */ | |
707 | void sctp_ulpq_reasm_flushtsn(struct sctp_ulpq *ulpq, __u32 fwd_tsn) | |
708 | { | |
709 | struct sk_buff *pos, *tmp; | |
710 | struct sctp_ulpevent *event; | |
711 | __u32 tsn; | |
712 | ||
713 | if (skb_queue_empty(&ulpq->reasm)) | |
714 | return; | |
715 | ||
716 | skb_queue_walk_safe(&ulpq->reasm, pos, tmp) { | |
717 | event = sctp_skb2event(pos); | |
718 | tsn = event->tsn; | |
719 | ||
720 | /* Since the entire message must be abandoned by the | |
721 | * sender (item A3 in Section 3.5, RFC 3758), we can | |
722 | * free all fragments on the list that are less then | |
723 | * or equal to ctsn_point | |
724 | */ | |
725 | if (TSN_lte(tsn, fwd_tsn)) { | |
726 | __skb_unlink(pos, &ulpq->reasm); | |
727 | sctp_ulpevent_free(event); | |
728 | } else | |
729 | break; | |
730 | } | |
731 | } | |
732 | ||
ef5d4cf2 VY |
733 | /* |
734 | * Drain the reassembly queue. If we just cleared parted delivery, it | |
735 | * is possible that the reassembly queue will contain already reassembled | |
736 | * messages. Retrieve any such messages and give them to the user. | |
737 | */ | |
738 | static void sctp_ulpq_reasm_drain(struct sctp_ulpq *ulpq) | |
739 | { | |
740 | struct sctp_ulpevent *event = NULL; | |
741 | struct sk_buff_head temp; | |
742 | ||
743 | if (skb_queue_empty(&ulpq->reasm)) | |
744 | return; | |
745 | ||
746 | while ((event = sctp_ulpq_retrieve_reassembled(ulpq)) != NULL) { | |
747 | /* Do ordering if needed. */ | |
cb3f837b | 748 | if ((event) && (event->msg_flags & MSG_EOR)) { |
ef5d4cf2 VY |
749 | skb_queue_head_init(&temp); |
750 | __skb_queue_tail(&temp, sctp_event2skb(event)); | |
751 | ||
752 | event = sctp_ulpq_order(ulpq, event); | |
753 | } | |
754 | ||
755 | /* Send event to the ULP. 'event' is the | |
756 | * sctp_ulpevent for very first SKB on the temp' list. | |
757 | */ | |
758 | if (event) | |
759 | sctp_ulpq_tail_event(ulpq, event); | |
760 | } | |
761 | } | |
762 | ||
763 | ||
1da177e4 LT |
764 | /* Helper function to gather skbs that have possibly become |
765 | * ordered by an an incoming chunk. | |
766 | */ | |
01f2d384 | 767 | static void sctp_ulpq_retrieve_ordered(struct sctp_ulpq *ulpq, |
1da177e4 LT |
768 | struct sctp_ulpevent *event) |
769 | { | |
8728b834 | 770 | struct sk_buff_head *event_list; |
1da177e4 LT |
771 | struct sk_buff *pos, *tmp; |
772 | struct sctp_ulpevent *cevent; | |
a8386317 | 773 | struct sctp_stream *stream; |
efea2c6b | 774 | __u16 sid, csid, cssn; |
1da177e4 LT |
775 | |
776 | sid = event->stream; | |
cee360ab | 777 | stream = &ulpq->asoc->stream; |
1da177e4 | 778 | |
8728b834 DM |
779 | event_list = (struct sk_buff_head *) sctp_event2skb(event)->prev; |
780 | ||
1da177e4 LT |
781 | /* We are holding the chunks by stream, by SSN. */ |
782 | sctp_skb_for_each(pos, &ulpq->lobby, tmp) { | |
783 | cevent = (struct sctp_ulpevent *) pos->cb; | |
784 | csid = cevent->stream; | |
785 | cssn = cevent->ssn; | |
786 | ||
787 | /* Have we gone too far? */ | |
788 | if (csid > sid) | |
789 | break; | |
790 | ||
791 | /* Have we not gone far enough? */ | |
792 | if (csid < sid) | |
793 | continue; | |
794 | ||
a8386317 | 795 | if (cssn != sctp_ssn_peek(stream, in, sid)) |
1da177e4 LT |
796 | break; |
797 | ||
a8386317 XL |
798 | /* Found it, so mark in the stream. */ |
799 | sctp_ssn_next(stream, in, sid); | |
1da177e4 | 800 | |
8728b834 | 801 | __skb_unlink(pos, &ulpq->lobby); |
1da177e4 LT |
802 | |
803 | /* Attach all gathered skbs to the event. */ | |
8728b834 | 804 | __skb_queue_tail(event_list, pos); |
1da177e4 LT |
805 | } |
806 | } | |
807 | ||
808 | /* Helper function to store chunks needing ordering. */ | |
01f2d384 | 809 | static void sctp_ulpq_store_ordered(struct sctp_ulpq *ulpq, |
1da177e4 LT |
810 | struct sctp_ulpevent *event) |
811 | { | |
812 | struct sk_buff *pos; | |
813 | struct sctp_ulpevent *cevent; | |
814 | __u16 sid, csid; | |
815 | __u16 ssn, cssn; | |
816 | ||
817 | pos = skb_peek_tail(&ulpq->lobby); | |
818 | if (!pos) { | |
819 | __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); | |
820 | return; | |
821 | } | |
822 | ||
823 | sid = event->stream; | |
824 | ssn = event->ssn; | |
d808ad9a | 825 | |
1da177e4 LT |
826 | cevent = (struct sctp_ulpevent *) pos->cb; |
827 | csid = cevent->stream; | |
828 | cssn = cevent->ssn; | |
829 | if (sid > csid) { | |
830 | __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); | |
831 | return; | |
832 | } | |
833 | ||
834 | if ((sid == csid) && SSN_lt(cssn, ssn)) { | |
835 | __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); | |
836 | return; | |
837 | } | |
838 | ||
839 | /* Find the right place in this list. We store them by | |
840 | * stream ID and then by SSN. | |
841 | */ | |
842 | skb_queue_walk(&ulpq->lobby, pos) { | |
843 | cevent = (struct sctp_ulpevent *) pos->cb; | |
844 | csid = cevent->stream; | |
845 | cssn = cevent->ssn; | |
846 | ||
847 | if (csid > sid) | |
848 | break; | |
849 | if (csid == sid && SSN_lt(ssn, cssn)) | |
850 | break; | |
851 | } | |
852 | ||
853 | ||
854 | /* Insert before pos. */ | |
43f59c89 | 855 | __skb_queue_before(&ulpq->lobby, pos, sctp_event2skb(event)); |
1da177e4 LT |
856 | } |
857 | ||
858 | static struct sctp_ulpevent *sctp_ulpq_order(struct sctp_ulpq *ulpq, | |
8728b834 | 859 | struct sctp_ulpevent *event) |
1da177e4 LT |
860 | { |
861 | __u16 sid, ssn; | |
a8386317 | 862 | struct sctp_stream *stream; |
1da177e4 LT |
863 | |
864 | /* Check if this message needs ordering. */ | |
bd4d627d | 865 | if (event->msg_flags & SCTP_DATA_UNORDERED) |
1da177e4 LT |
866 | return event; |
867 | ||
868 | /* Note: The stream ID must be verified before this routine. */ | |
869 | sid = event->stream; | |
870 | ssn = event->ssn; | |
cee360ab | 871 | stream = &ulpq->asoc->stream; |
1da177e4 LT |
872 | |
873 | /* Is this the expected SSN for this stream ID? */ | |
a8386317 | 874 | if (ssn != sctp_ssn_peek(stream, in, sid)) { |
1da177e4 LT |
875 | /* We've received something out of order, so find where it |
876 | * needs to be placed. We order by stream and then by SSN. | |
877 | */ | |
878 | sctp_ulpq_store_ordered(ulpq, event); | |
879 | return NULL; | |
880 | } | |
881 | ||
882 | /* Mark that the next chunk has been found. */ | |
a8386317 | 883 | sctp_ssn_next(stream, in, sid); |
1da177e4 LT |
884 | |
885 | /* Go find any other chunks that were waiting for | |
886 | * ordering. | |
887 | */ | |
888 | sctp_ulpq_retrieve_ordered(ulpq, event); | |
889 | ||
890 | return event; | |
891 | } | |
892 | ||
893 | /* Helper function to gather skbs that have possibly become | |
894 | * ordered by forward tsn skipping their dependencies. | |
895 | */ | |
01f2d384 | 896 | static void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq, __u16 sid) |
1da177e4 LT |
897 | { |
898 | struct sk_buff *pos, *tmp; | |
899 | struct sctp_ulpevent *cevent; | |
8728b834 | 900 | struct sctp_ulpevent *event; |
a8386317 | 901 | struct sctp_stream *stream; |
1da177e4 | 902 | struct sk_buff_head temp; |
c068be54 | 903 | struct sk_buff_head *lobby = &ulpq->lobby; |
1da177e4 LT |
904 | __u16 csid, cssn; |
905 | ||
cee360ab | 906 | stream = &ulpq->asoc->stream; |
1da177e4 LT |
907 | |
908 | /* We are holding the chunks by stream, by SSN. */ | |
8728b834 DM |
909 | skb_queue_head_init(&temp); |
910 | event = NULL; | |
c068be54 | 911 | sctp_skb_for_each(pos, lobby, tmp) { |
1da177e4 LT |
912 | cevent = (struct sctp_ulpevent *) pos->cb; |
913 | csid = cevent->stream; | |
914 | cssn = cevent->ssn; | |
915 | ||
ea2dfb37 VY |
916 | /* Have we gone too far? */ |
917 | if (csid > sid) | |
1da177e4 LT |
918 | break; |
919 | ||
ea2dfb37 VY |
920 | /* Have we not gone far enough? */ |
921 | if (csid < sid) | |
922 | continue; | |
923 | ||
924 | /* see if this ssn has been marked by skipping */ | |
a8386317 | 925 | if (!SSN_lt(cssn, sctp_ssn_peek(stream, in, csid))) |
ea2dfb37 | 926 | break; |
1da177e4 | 927 | |
c068be54 | 928 | __skb_unlink(pos, lobby); |
ea2dfb37 | 929 | if (!event) |
1da177e4 LT |
930 | /* Create a temporary list to collect chunks on. */ |
931 | event = sctp_skb2event(pos); | |
ea2dfb37 VY |
932 | |
933 | /* Attach all gathered skbs to the event. */ | |
934 | __skb_queue_tail(&temp, pos); | |
1da177e4 LT |
935 | } |
936 | ||
c068be54 VY |
937 | /* If we didn't reap any data, see if the next expected SSN |
938 | * is next on the queue and if so, use that. | |
939 | */ | |
940 | if (event == NULL && pos != (struct sk_buff *)lobby) { | |
941 | cevent = (struct sctp_ulpevent *) pos->cb; | |
942 | csid = cevent->stream; | |
943 | cssn = cevent->ssn; | |
944 | ||
a8386317 XL |
945 | if (csid == sid && cssn == sctp_ssn_peek(stream, in, csid)) { |
946 | sctp_ssn_next(stream, in, csid); | |
c068be54 VY |
947 | __skb_unlink(pos, lobby); |
948 | __skb_queue_tail(&temp, pos); | |
949 | event = sctp_skb2event(pos); | |
950 | } | |
951 | } | |
952 | ||
8728b834 DM |
953 | /* Send event to the ULP. 'event' is the sctp_ulpevent for |
954 | * very first SKB on the 'temp' list. | |
955 | */ | |
ea2dfb37 VY |
956 | if (event) { |
957 | /* see if we have more ordered that we can deliver */ | |
958 | sctp_ulpq_retrieve_ordered(ulpq, event); | |
1da177e4 | 959 | sctp_ulpq_tail_event(ulpq, event); |
ea2dfb37 | 960 | } |
1da177e4 LT |
961 | } |
962 | ||
ea2dfb37 VY |
963 | /* Skip over an SSN. This is used during the processing of |
964 | * Forwared TSN chunk to skip over the abandoned ordered data | |
965 | */ | |
1da177e4 LT |
966 | void sctp_ulpq_skip(struct sctp_ulpq *ulpq, __u16 sid, __u16 ssn) |
967 | { | |
a8386317 | 968 | struct sctp_stream *stream; |
1da177e4 LT |
969 | |
970 | /* Note: The stream ID must be verified before this routine. */ | |
cee360ab | 971 | stream = &ulpq->asoc->stream; |
1da177e4 LT |
972 | |
973 | /* Is this an old SSN? If so ignore. */ | |
a8386317 | 974 | if (SSN_lt(ssn, sctp_ssn_peek(stream, in, sid))) |
1da177e4 LT |
975 | return; |
976 | ||
977 | /* Mark that we are no longer expecting this SSN or lower. */ | |
a8386317 | 978 | sctp_ssn_skip(stream, in, sid, ssn); |
1da177e4 LT |
979 | |
980 | /* Go find any other chunks that were waiting for | |
d808ad9a | 981 | * ordering and deliver them if needed. |
1da177e4 | 982 | */ |
ea2dfb37 | 983 | sctp_ulpq_reap_ordered(ulpq, sid); |
1da177e4 LT |
984 | } |
985 | ||
94014e8d XL |
986 | __u16 sctp_ulpq_renege_list(struct sctp_ulpq *ulpq, struct sk_buff_head *list, |
987 | __u16 needed) | |
1da177e4 LT |
988 | { |
989 | __u16 freed = 0; | |
95ac7b85 LR |
990 | __u32 tsn, last_tsn; |
991 | struct sk_buff *skb, *flist, *last; | |
1da177e4 LT |
992 | struct sctp_ulpevent *event; |
993 | struct sctp_tsnmap *tsnmap; | |
994 | ||
995 | tsnmap = &ulpq->asoc->peer.tsn_map; | |
996 | ||
e67f85ec | 997 | while ((skb = skb_peek_tail(list)) != NULL) { |
1da177e4 LT |
998 | event = sctp_skb2event(skb); |
999 | tsn = event->tsn; | |
1000 | ||
e67f85ec LR |
1001 | /* Don't renege below the Cumulative TSN ACK Point. */ |
1002 | if (TSN_lte(tsn, sctp_tsnmap_get_ctsn(tsnmap))) | |
1003 | break; | |
1004 | ||
95ac7b85 LR |
1005 | /* Events in ordering queue may have multiple fragments |
1006 | * corresponding to additional TSNs. Sum the total | |
1007 | * freed space; find the last TSN. | |
1008 | */ | |
e67f85ec | 1009 | freed += skb_headlen(skb); |
95ac7b85 LR |
1010 | flist = skb_shinfo(skb)->frag_list; |
1011 | for (last = flist; flist; flist = flist->next) { | |
1012 | last = flist; | |
1013 | freed += skb_headlen(last); | |
1014 | } | |
1015 | if (last) | |
1016 | last_tsn = sctp_skb2event(last)->tsn; | |
1017 | else | |
1018 | last_tsn = tsn; | |
1019 | ||
1020 | /* Unlink the event, then renege all applicable TSNs. */ | |
1021 | __skb_unlink(skb, list); | |
1da177e4 | 1022 | sctp_ulpevent_free(event); |
95ac7b85 LR |
1023 | while (TSN_lte(tsn, last_tsn)) { |
1024 | sctp_tsnmap_renege(tsnmap, tsn); | |
1025 | tsn++; | |
1026 | } | |
1da177e4 LT |
1027 | if (freed >= needed) |
1028 | return freed; | |
1029 | } | |
1030 | ||
1031 | return freed; | |
1032 | } | |
1033 | ||
16d14ef9 PE |
1034 | /* Renege 'needed' bytes from the ordering queue. */ |
1035 | static __u16 sctp_ulpq_renege_order(struct sctp_ulpq *ulpq, __u16 needed) | |
1036 | { | |
1037 | return sctp_ulpq_renege_list(ulpq, &ulpq->lobby, needed); | |
1038 | } | |
1039 | ||
1da177e4 LT |
1040 | /* Renege 'needed' bytes from the reassembly queue. */ |
1041 | static __u16 sctp_ulpq_renege_frags(struct sctp_ulpq *ulpq, __u16 needed) | |
1042 | { | |
16d14ef9 | 1043 | return sctp_ulpq_renege_list(ulpq, &ulpq->reasm, needed); |
1da177e4 LT |
1044 | } |
1045 | ||
1046 | /* Partial deliver the first message as there is pressure on rwnd. */ | |
1047 | void sctp_ulpq_partial_delivery(struct sctp_ulpq *ulpq, | |
dd0fc66f | 1048 | gfp_t gfp) |
1da177e4 LT |
1049 | { |
1050 | struct sctp_ulpevent *event; | |
1051 | struct sctp_association *asoc; | |
b6e1331f | 1052 | struct sctp_sock *sp; |
d003b41b LR |
1053 | __u32 ctsn; |
1054 | struct sk_buff *skb; | |
1da177e4 LT |
1055 | |
1056 | asoc = ulpq->asoc; | |
b6e1331f | 1057 | sp = sctp_sk(asoc->base.sk); |
1da177e4 | 1058 | |
b6e1331f | 1059 | /* If the association is already in Partial Delivery mode |
d003b41b | 1060 | * we have nothing to do. |
b6e1331f VY |
1061 | */ |
1062 | if (ulpq->pd_mode) | |
1063 | return; | |
1da177e4 | 1064 | |
d003b41b LR |
1065 | /* Data must be at or below the Cumulative TSN ACK Point to |
1066 | * start partial delivery. | |
1067 | */ | |
1068 | skb = skb_peek(&asoc->ulpq.reasm); | |
1069 | if (skb != NULL) { | |
1070 | ctsn = sctp_skb2event(skb)->tsn; | |
1071 | if (!TSN_lte(ctsn, sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map))) | |
1072 | return; | |
1073 | } | |
1074 | ||
b6e1331f VY |
1075 | /* If the user enabled fragment interleave socket option, |
1076 | * multiple associations can enter partial delivery. | |
1077 | * Otherwise, we can only enter partial delivery if the | |
1078 | * socket is not in partial deliver mode. | |
1079 | */ | |
1080 | if (sp->frag_interleave || atomic_read(&sp->pd_mode) == 0) { | |
1da177e4 LT |
1081 | /* Is partial delivery possible? */ |
1082 | event = sctp_ulpq_retrieve_first(ulpq); | |
1083 | /* Send event to the ULP. */ | |
1084 | if (event) { | |
1085 | sctp_ulpq_tail_event(ulpq, event); | |
d49d91d7 | 1086 | sctp_ulpq_set_pd(ulpq); |
1da177e4 LT |
1087 | return; |
1088 | } | |
1089 | } | |
1090 | } | |
1091 | ||
1092 | /* Renege some packets to make room for an incoming chunk. */ | |
1093 | void sctp_ulpq_renege(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk, | |
dd0fc66f | 1094 | gfp_t gfp) |
1da177e4 | 1095 | { |
5c468674 XL |
1096 | struct sctp_association *asoc = ulpq->asoc; |
1097 | __u32 freed = 0; | |
1098 | __u16 needed; | |
1da177e4 | 1099 | |
5c468674 XL |
1100 | needed = ntohs(chunk->chunk_hdr->length) - |
1101 | sizeof(struct sctp_data_chunk); | |
1da177e4 LT |
1102 | |
1103 | if (skb_queue_empty(&asoc->base.sk->sk_receive_queue)) { | |
1104 | freed = sctp_ulpq_renege_order(ulpq, needed); | |
5c468674 | 1105 | if (freed < needed) |
1da177e4 | 1106 | freed += sctp_ulpq_renege_frags(ulpq, needed - freed); |
1da177e4 LT |
1107 | } |
1108 | /* If able to free enough room, accept this chunk. */ | |
5c468674 XL |
1109 | if (freed >= needed) { |
1110 | int retval = sctp_ulpq_tail_data(ulpq, chunk, gfp); | |
d003b41b LR |
1111 | /* |
1112 | * Enter partial delivery if chunk has not been | |
1113 | * delivered; otherwise, drain the reassembly queue. | |
1114 | */ | |
1115 | if (retval <= 0) | |
1116 | sctp_ulpq_partial_delivery(ulpq, gfp); | |
1117 | else if (retval == 1) | |
1118 | sctp_ulpq_reasm_drain(ulpq); | |
1da177e4 LT |
1119 | } |
1120 | ||
3ab224be | 1121 | sk_mem_reclaim(asoc->base.sk); |
1da177e4 LT |
1122 | } |
1123 | ||
1124 | ||
1125 | ||
1126 | /* Notify the application if an association is aborted and in | |
1127 | * partial delivery mode. Send up any pending received messages. | |
1128 | */ | |
dd0fc66f | 1129 | void sctp_ulpq_abort_pd(struct sctp_ulpq *ulpq, gfp_t gfp) |
1da177e4 LT |
1130 | { |
1131 | struct sctp_ulpevent *ev = NULL; | |
1132 | struct sock *sk; | |
0970f5b3 | 1133 | struct sctp_sock *sp; |
1da177e4 LT |
1134 | |
1135 | if (!ulpq->pd_mode) | |
1136 | return; | |
1137 | ||
1138 | sk = ulpq->asoc->base.sk; | |
0970f5b3 | 1139 | sp = sctp_sk(sk); |
1da177e4 LT |
1140 | if (sctp_ulpevent_type_enabled(SCTP_PARTIAL_DELIVERY_EVENT, |
1141 | &sctp_sk(sk)->subscribe)) | |
1142 | ev = sctp_ulpevent_make_pdapi(ulpq->asoc, | |
1143 | SCTP_PARTIAL_DELIVERY_ABORTED, | |
65f5e357 | 1144 | 0, 0, 0, gfp); |
1da177e4 LT |
1145 | if (ev) |
1146 | __skb_queue_tail(&sk->sk_receive_queue, sctp_event2skb(ev)); | |
1147 | ||
1148 | /* If there is data waiting, send it up the socket now. */ | |
0970f5b3 MRL |
1149 | if ((sctp_ulpq_clear_pd(ulpq) || ev) && !sp->data_ready_signalled) { |
1150 | sp->data_ready_signalled = 1; | |
1151 | sk->sk_data_ready(sk); | |
1152 | } | |
1da177e4 | 1153 | } |