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1// SPDX-License-Identifier: GPL-2.0-or-later
2/* SCTP kernel implementation
3 * (C) Copyright IBM Corp. 2001, 2004
4 * Copyright (c) 1999-2000 Cisco, Inc.
5 * Copyright (c) 1999-2001 Motorola, Inc.
6 * Copyright (c) 2001 Intel Corp.
7 * Copyright (c) 2001 Nokia, Inc.
8 * Copyright (c) 2001 La Monte H.P. Yarroll
9 *
10 * These functions manipulate an sctp event. The struct ulpevent is used
11 * to carry notifications and data to the ULP (sockets).
12 *
13 * Please send any bug reports or fixes you make to the
14 * email address(es):
15 * lksctp developers <linux-sctp@vger.kernel.org>
16 *
17 * Written or modified by:
18 * Jon Grimm <jgrimm@us.ibm.com>
19 * La Monte H.P. Yarroll <piggy@acm.org>
20 * Ardelle Fan <ardelle.fan@intel.com>
21 * Sridhar Samudrala <sri@us.ibm.com>
22 */
23
24#include <linux/slab.h>
25#include <linux/types.h>
26#include <linux/skbuff.h>
27#include <net/sctp/structs.h>
28#include <net/sctp/sctp.h>
29#include <net/sctp/sm.h>
30
31static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
32 struct sctp_association *asoc);
33static void sctp_ulpevent_release_data(struct sctp_ulpevent *event);
34static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event);
35
36
37/* Initialize an ULP event from an given skb. */
38static void sctp_ulpevent_init(struct sctp_ulpevent *event,
39 __u16 msg_flags,
40 unsigned int len)
41{
42 memset(event, 0, sizeof(struct sctp_ulpevent));
43 event->msg_flags = msg_flags;
44 event->rmem_len = len;
45}
46
47/* Create a new sctp_ulpevent. */
48static struct sctp_ulpevent *sctp_ulpevent_new(int size, __u16 msg_flags,
49 gfp_t gfp)
50{
51 struct sctp_ulpevent *event;
52 struct sk_buff *skb;
53
54 skb = alloc_skb(size, gfp);
55 if (!skb)
56 goto fail;
57
58 event = sctp_skb2event(skb);
59 sctp_ulpevent_init(event, msg_flags, skb->truesize);
60
61 return event;
62
63fail:
64 return NULL;
65}
66
67/* Is this a MSG_NOTIFICATION? */
68int sctp_ulpevent_is_notification(const struct sctp_ulpevent *event)
69{
70 return MSG_NOTIFICATION == (event->msg_flags & MSG_NOTIFICATION);
71}
72
73/* Hold the association in case the msg_name needs read out of
74 * the association.
75 */
76static inline void sctp_ulpevent_set_owner(struct sctp_ulpevent *event,
77 const struct sctp_association *asoc)
78{
79 struct sctp_chunk *chunk = event->chunk;
80 struct sk_buff *skb;
81
82 /* Cast away the const, as we are just wanting to
83 * bump the reference count.
84 */
85 sctp_association_hold((struct sctp_association *)asoc);
86 skb = sctp_event2skb(event);
87 event->asoc = (struct sctp_association *)asoc;
88 atomic_add(event->rmem_len, &event->asoc->rmem_alloc);
89 sctp_skb_set_owner_r(skb, asoc->base.sk);
90 if (chunk && chunk->head_skb && !chunk->head_skb->sk)
91 chunk->head_skb->sk = asoc->base.sk;
92}
93
94/* A simple destructor to give up the reference to the association. */
95static inline void sctp_ulpevent_release_owner(struct sctp_ulpevent *event)
96{
97 struct sctp_association *asoc = event->asoc;
98
99 atomic_sub(event->rmem_len, &asoc->rmem_alloc);
100 sctp_association_put(asoc);
101}
102
103/* Create and initialize an SCTP_ASSOC_CHANGE event.
104 *
105 * 5.3.1.1 SCTP_ASSOC_CHANGE
106 *
107 * Communication notifications inform the ULP that an SCTP association
108 * has either begun or ended. The identifier for a new association is
109 * provided by this notification.
110 *
111 * Note: There is no field checking here. If a field is unused it will be
112 * zero'd out.
113 */
114struct sctp_ulpevent *sctp_ulpevent_make_assoc_change(
115 const struct sctp_association *asoc,
116 __u16 flags, __u16 state, __u16 error, __u16 outbound,
117 __u16 inbound, struct sctp_chunk *chunk, gfp_t gfp)
118{
119 struct sctp_ulpevent *event;
120 struct sctp_assoc_change *sac;
121 struct sk_buff *skb;
122
123 /* If the lower layer passed in the chunk, it will be
124 * an ABORT, so we need to include it in the sac_info.
125 */
126 if (chunk) {
127 /* Copy the chunk data to a new skb and reserve enough
128 * head room to use as notification.
129 */
130 skb = skb_copy_expand(chunk->skb,
131 sizeof(struct sctp_assoc_change), 0, gfp);
132
133 if (!skb)
134 goto fail;
135
136 /* Embed the event fields inside the cloned skb. */
137 event = sctp_skb2event(skb);
138 sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
139
140 /* Include the notification structure */
141 sac = skb_push(skb, sizeof(struct sctp_assoc_change));
142
143 /* Trim the buffer to the right length. */
144 skb_trim(skb, sizeof(struct sctp_assoc_change) +
145 ntohs(chunk->chunk_hdr->length) -
146 sizeof(struct sctp_chunkhdr));
147 } else {
148 event = sctp_ulpevent_new(sizeof(struct sctp_assoc_change),
149 MSG_NOTIFICATION, gfp);
150 if (!event)
151 goto fail;
152
153 skb = sctp_event2skb(event);
154 sac = skb_put(skb, sizeof(struct sctp_assoc_change));
155 }
156
157 /* Socket Extensions for SCTP
158 * 5.3.1.1 SCTP_ASSOC_CHANGE
159 *
160 * sac_type:
161 * It should be SCTP_ASSOC_CHANGE.
162 */
163 sac->sac_type = SCTP_ASSOC_CHANGE;
164
165 /* Socket Extensions for SCTP
166 * 5.3.1.1 SCTP_ASSOC_CHANGE
167 *
168 * sac_state: 32 bits (signed integer)
169 * This field holds one of a number of values that communicate the
170 * event that happened to the association.
171 */
172 sac->sac_state = state;
173
174 /* Socket Extensions for SCTP
175 * 5.3.1.1 SCTP_ASSOC_CHANGE
176 *
177 * sac_flags: 16 bits (unsigned integer)
178 * Currently unused.
179 */
180 sac->sac_flags = 0;
181
182 /* Socket Extensions for SCTP
183 * 5.3.1.1 SCTP_ASSOC_CHANGE
184 *
185 * sac_length: sizeof (__u32)
186 * This field is the total length of the notification data, including
187 * the notification header.
188 */
189 sac->sac_length = skb->len;
190
191 /* Socket Extensions for SCTP
192 * 5.3.1.1 SCTP_ASSOC_CHANGE
193 *
194 * sac_error: 32 bits (signed integer)
195 *
196 * If the state was reached due to a error condition (e.g.
197 * COMMUNICATION_LOST) any relevant error information is available in
198 * this field. This corresponds to the protocol error codes defined in
199 * [SCTP].
200 */
201 sac->sac_error = error;
202
203 /* Socket Extensions for SCTP
204 * 5.3.1.1 SCTP_ASSOC_CHANGE
205 *
206 * sac_outbound_streams: 16 bits (unsigned integer)
207 * sac_inbound_streams: 16 bits (unsigned integer)
208 *
209 * The maximum number of streams allowed in each direction are
210 * available in sac_outbound_streams and sac_inbound streams.
211 */
212 sac->sac_outbound_streams = outbound;
213 sac->sac_inbound_streams = inbound;
214
215 /* Socket Extensions for SCTP
216 * 5.3.1.1 SCTP_ASSOC_CHANGE
217 *
218 * sac_assoc_id: sizeof (sctp_assoc_t)
219 *
220 * The association id field, holds the identifier for the association.
221 * All notifications for a given association have the same association
222 * identifier. For TCP style socket, this field is ignored.
223 */
224 sctp_ulpevent_set_owner(event, asoc);
225 sac->sac_assoc_id = sctp_assoc2id(asoc);
226
227 return event;
228
229fail:
230 return NULL;
231}
232
233/* Create and initialize an SCTP_PEER_ADDR_CHANGE event.
234 *
235 * Socket Extensions for SCTP - draft-01
236 * 5.3.1.2 SCTP_PEER_ADDR_CHANGE
237 *
238 * When a destination address on a multi-homed peer encounters a change
239 * an interface details event is sent.
240 */
241static struct sctp_ulpevent *sctp_ulpevent_make_peer_addr_change(
242 const struct sctp_association *asoc,
243 const struct sockaddr_storage *aaddr,
244 int flags, int state, int error, gfp_t gfp)
245{
246 struct sctp_ulpevent *event;
247 struct sctp_paddr_change *spc;
248 struct sk_buff *skb;
249
250 event = sctp_ulpevent_new(sizeof(struct sctp_paddr_change),
251 MSG_NOTIFICATION, gfp);
252 if (!event)
253 goto fail;
254
255 skb = sctp_event2skb(event);
256 spc = skb_put(skb, sizeof(struct sctp_paddr_change));
257
258 /* Sockets API Extensions for SCTP
259 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
260 *
261 * spc_type:
262 *
263 * It should be SCTP_PEER_ADDR_CHANGE.
264 */
265 spc->spc_type = SCTP_PEER_ADDR_CHANGE;
266
267 /* Sockets API Extensions for SCTP
268 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
269 *
270 * spc_length: sizeof (__u32)
271 *
272 * This field is the total length of the notification data, including
273 * the notification header.
274 */
275 spc->spc_length = sizeof(struct sctp_paddr_change);
276
277 /* Sockets API Extensions for SCTP
278 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
279 *
280 * spc_flags: 16 bits (unsigned integer)
281 * Currently unused.
282 */
283 spc->spc_flags = 0;
284
285 /* Sockets API Extensions for SCTP
286 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
287 *
288 * spc_state: 32 bits (signed integer)
289 *
290 * This field holds one of a number of values that communicate the
291 * event that happened to the address.
292 */
293 spc->spc_state = state;
294
295 /* Sockets API Extensions for SCTP
296 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
297 *
298 * spc_error: 32 bits (signed integer)
299 *
300 * If the state was reached due to any error condition (e.g.
301 * ADDRESS_UNREACHABLE) any relevant error information is available in
302 * this field.
303 */
304 spc->spc_error = error;
305
306 /* Socket Extensions for SCTP
307 * 5.3.1.1 SCTP_ASSOC_CHANGE
308 *
309 * spc_assoc_id: sizeof (sctp_assoc_t)
310 *
311 * The association id field, holds the identifier for the association.
312 * All notifications for a given association have the same association
313 * identifier. For TCP style socket, this field is ignored.
314 */
315 sctp_ulpevent_set_owner(event, asoc);
316 spc->spc_assoc_id = sctp_assoc2id(asoc);
317
318 /* Sockets API Extensions for SCTP
319 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
320 *
321 * spc_aaddr: sizeof (struct sockaddr_storage)
322 *
323 * The affected address field, holds the remote peer's address that is
324 * encountering the change of state.
325 */
326 memcpy(&spc->spc_aaddr, aaddr, sizeof(struct sockaddr_storage));
327
328 /* Map ipv4 address into v4-mapped-on-v6 address. */
329 sctp_get_pf_specific(asoc->base.sk->sk_family)->addr_to_user(
330 sctp_sk(asoc->base.sk),
331 (union sctp_addr *)&spc->spc_aaddr);
332
333 return event;
334
335fail:
336 return NULL;
337}
338
339void sctp_ulpevent_notify_peer_addr_change(struct sctp_transport *transport,
340 int state, int error)
341{
342 struct sctp_association *asoc = transport->asoc;
343 struct sockaddr_storage addr;
344 struct sctp_ulpevent *event;
345
346 if (asoc->state < SCTP_STATE_ESTABLISHED)
347 return;
348
349 memset(&addr, 0, sizeof(struct sockaddr_storage));
350 memcpy(&addr, &transport->ipaddr, transport->af_specific->sockaddr_len);
351
352 event = sctp_ulpevent_make_peer_addr_change(asoc, &addr, 0, state,
353 error, GFP_ATOMIC);
354 if (event)
355 asoc->stream.si->enqueue_event(&asoc->ulpq, event);
356}
357
358/* Create and initialize an SCTP_REMOTE_ERROR notification.
359 *
360 * Note: This assumes that the chunk->skb->data already points to the
361 * operation error payload.
362 *
363 * Socket Extensions for SCTP - draft-01
364 * 5.3.1.3 SCTP_REMOTE_ERROR
365 *
366 * A remote peer may send an Operational Error message to its peer.
367 * This message indicates a variety of error conditions on an
368 * association. The entire error TLV as it appears on the wire is
369 * included in a SCTP_REMOTE_ERROR event. Please refer to the SCTP
370 * specification [SCTP] and any extensions for a list of possible
371 * error formats.
372 */
373struct sctp_ulpevent *
374sctp_ulpevent_make_remote_error(const struct sctp_association *asoc,
375 struct sctp_chunk *chunk, __u16 flags,
376 gfp_t gfp)
377{
378 struct sctp_remote_error *sre;
379 struct sctp_ulpevent *event;
380 struct sctp_errhdr *ch;
381 struct sk_buff *skb;
382 __be16 cause;
383 int elen;
384
385 ch = (struct sctp_errhdr *)(chunk->skb->data);
386 cause = ch->cause;
387 elen = SCTP_PAD4(ntohs(ch->length)) - sizeof(*ch);
388
389 /* Pull off the ERROR header. */
390 skb_pull(chunk->skb, sizeof(*ch));
391
392 /* Copy the skb to a new skb with room for us to prepend
393 * notification with.
394 */
395 skb = skb_copy_expand(chunk->skb, sizeof(*sre), 0, gfp);
396
397 /* Pull off the rest of the cause TLV from the chunk. */
398 skb_pull(chunk->skb, elen);
399 if (!skb)
400 goto fail;
401
402 /* Embed the event fields inside the cloned skb. */
403 event = sctp_skb2event(skb);
404 sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
405
406 sre = skb_push(skb, sizeof(*sre));
407
408 /* Trim the buffer to the right length. */
409 skb_trim(skb, sizeof(*sre) + elen);
410
411 /* RFC6458, Section 6.1.3. SCTP_REMOTE_ERROR */
412 memset(sre, 0, sizeof(*sre));
413 sre->sre_type = SCTP_REMOTE_ERROR;
414 sre->sre_flags = 0;
415 sre->sre_length = skb->len;
416 sre->sre_error = cause;
417 sctp_ulpevent_set_owner(event, asoc);
418 sre->sre_assoc_id = sctp_assoc2id(asoc);
419
420 return event;
421fail:
422 return NULL;
423}
424
425/* Create and initialize a SCTP_SEND_FAILED notification.
426 *
427 * Socket Extensions for SCTP - draft-01
428 * 5.3.1.4 SCTP_SEND_FAILED
429 */
430struct sctp_ulpevent *sctp_ulpevent_make_send_failed(
431 const struct sctp_association *asoc, struct sctp_chunk *chunk,
432 __u16 flags, __u32 error, gfp_t gfp)
433{
434 struct sctp_ulpevent *event;
435 struct sctp_send_failed *ssf;
436 struct sk_buff *skb;
437
438 /* Pull off any padding. */
439 int len = ntohs(chunk->chunk_hdr->length);
440
441 /* Make skb with more room so we can prepend notification. */
442 skb = skb_copy_expand(chunk->skb,
443 sizeof(struct sctp_send_failed), /* headroom */
444 0, /* tailroom */
445 gfp);
446 if (!skb)
447 goto fail;
448
449 /* Pull off the common chunk header and DATA header. */
450 skb_pull(skb, sctp_datachk_len(&asoc->stream));
451 len -= sctp_datachk_len(&asoc->stream);
452
453 /* Embed the event fields inside the cloned skb. */
454 event = sctp_skb2event(skb);
455 sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
456
457 ssf = skb_push(skb, sizeof(struct sctp_send_failed));
458
459 /* Socket Extensions for SCTP
460 * 5.3.1.4 SCTP_SEND_FAILED
461 *
462 * ssf_type:
463 * It should be SCTP_SEND_FAILED.
464 */
465 ssf->ssf_type = SCTP_SEND_FAILED;
466
467 /* Socket Extensions for SCTP
468 * 5.3.1.4 SCTP_SEND_FAILED
469 *
470 * ssf_flags: 16 bits (unsigned integer)
471 * The flag value will take one of the following values
472 *
473 * SCTP_DATA_UNSENT - Indicates that the data was never put on
474 * the wire.
475 *
476 * SCTP_DATA_SENT - Indicates that the data was put on the wire.
477 * Note that this does not necessarily mean that the
478 * data was (or was not) successfully delivered.
479 */
480 ssf->ssf_flags = flags;
481
482 /* Socket Extensions for SCTP
483 * 5.3.1.4 SCTP_SEND_FAILED
484 *
485 * ssf_length: sizeof (__u32)
486 * This field is the total length of the notification data, including
487 * the notification header.
488 */
489 ssf->ssf_length = sizeof(struct sctp_send_failed) + len;
490 skb_trim(skb, ssf->ssf_length);
491
492 /* Socket Extensions for SCTP
493 * 5.3.1.4 SCTP_SEND_FAILED
494 *
495 * ssf_error: 16 bits (unsigned integer)
496 * This value represents the reason why the send failed, and if set,
497 * will be a SCTP protocol error code as defined in [SCTP] section
498 * 3.3.10.
499 */
500 ssf->ssf_error = error;
501
502 /* Socket Extensions for SCTP
503 * 5.3.1.4 SCTP_SEND_FAILED
504 *
505 * ssf_info: sizeof (struct sctp_sndrcvinfo)
506 * The original send information associated with the undelivered
507 * message.
508 */
509 memcpy(&ssf->ssf_info, &chunk->sinfo, sizeof(struct sctp_sndrcvinfo));
510
511 /* Per TSVWG discussion with Randy. Allow the application to
512 * reassemble a fragmented message.
513 */
514 ssf->ssf_info.sinfo_flags = chunk->chunk_hdr->flags;
515
516 /* Socket Extensions for SCTP
517 * 5.3.1.4 SCTP_SEND_FAILED
518 *
519 * ssf_assoc_id: sizeof (sctp_assoc_t)
520 * The association id field, sf_assoc_id, holds the identifier for the
521 * association. All notifications for a given association have the
522 * same association identifier. For TCP style socket, this field is
523 * ignored.
524 */
525 sctp_ulpevent_set_owner(event, asoc);
526 ssf->ssf_assoc_id = sctp_assoc2id(asoc);
527 return event;
528
529fail:
530 return NULL;
531}
532
533struct sctp_ulpevent *sctp_ulpevent_make_send_failed_event(
534 const struct sctp_association *asoc, struct sctp_chunk *chunk,
535 __u16 flags, __u32 error, gfp_t gfp)
536{
537 struct sctp_send_failed_event *ssf;
538 struct sctp_ulpevent *event;
539 struct sk_buff *skb;
540 int len;
541
542 skb = skb_copy_expand(chunk->skb, sizeof(*ssf), 0, gfp);
543 if (!skb)
544 return NULL;
545
546 len = ntohs(chunk->chunk_hdr->length);
547 len -= sctp_datachk_len(&asoc->stream);
548
549 skb_pull(skb, sctp_datachk_len(&asoc->stream));
550 event = sctp_skb2event(skb);
551 sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
552
553 ssf = skb_push(skb, sizeof(*ssf));
554 ssf->ssf_type = SCTP_SEND_FAILED_EVENT;
555 ssf->ssf_flags = flags;
556 ssf->ssf_length = sizeof(*ssf) + len;
557 skb_trim(skb, ssf->ssf_length);
558 ssf->ssf_error = error;
559
560 ssf->ssfe_info.snd_sid = chunk->sinfo.sinfo_stream;
561 ssf->ssfe_info.snd_ppid = chunk->sinfo.sinfo_ppid;
562 ssf->ssfe_info.snd_context = chunk->sinfo.sinfo_context;
563 ssf->ssfe_info.snd_assoc_id = chunk->sinfo.sinfo_assoc_id;
564 ssf->ssfe_info.snd_flags = chunk->chunk_hdr->flags;
565
566 sctp_ulpevent_set_owner(event, asoc);
567 ssf->ssf_assoc_id = sctp_assoc2id(asoc);
568
569 return event;
570}
571
572/* Create and initialize a SCTP_SHUTDOWN_EVENT notification.
573 *
574 * Socket Extensions for SCTP - draft-01
575 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
576 */
577struct sctp_ulpevent *sctp_ulpevent_make_shutdown_event(
578 const struct sctp_association *asoc,
579 __u16 flags, gfp_t gfp)
580{
581 struct sctp_ulpevent *event;
582 struct sctp_shutdown_event *sse;
583 struct sk_buff *skb;
584
585 event = sctp_ulpevent_new(sizeof(struct sctp_shutdown_event),
586 MSG_NOTIFICATION, gfp);
587 if (!event)
588 goto fail;
589
590 skb = sctp_event2skb(event);
591 sse = skb_put(skb, sizeof(struct sctp_shutdown_event));
592
593 /* Socket Extensions for SCTP
594 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
595 *
596 * sse_type
597 * It should be SCTP_SHUTDOWN_EVENT
598 */
599 sse->sse_type = SCTP_SHUTDOWN_EVENT;
600
601 /* Socket Extensions for SCTP
602 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
603 *
604 * sse_flags: 16 bits (unsigned integer)
605 * Currently unused.
606 */
607 sse->sse_flags = 0;
608
609 /* Socket Extensions for SCTP
610 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
611 *
612 * sse_length: sizeof (__u32)
613 * This field is the total length of the notification data, including
614 * the notification header.
615 */
616 sse->sse_length = sizeof(struct sctp_shutdown_event);
617
618 /* Socket Extensions for SCTP
619 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
620 *
621 * sse_assoc_id: sizeof (sctp_assoc_t)
622 * The association id field, holds the identifier for the association.
623 * All notifications for a given association have the same association
624 * identifier. For TCP style socket, this field is ignored.
625 */
626 sctp_ulpevent_set_owner(event, asoc);
627 sse->sse_assoc_id = sctp_assoc2id(asoc);
628
629 return event;
630
631fail:
632 return NULL;
633}
634
635/* Create and initialize a SCTP_ADAPTATION_INDICATION notification.
636 *
637 * Socket Extensions for SCTP
638 * 5.3.1.6 SCTP_ADAPTATION_INDICATION
639 */
640struct sctp_ulpevent *sctp_ulpevent_make_adaptation_indication(
641 const struct sctp_association *asoc, gfp_t gfp)
642{
643 struct sctp_ulpevent *event;
644 struct sctp_adaptation_event *sai;
645 struct sk_buff *skb;
646
647 event = sctp_ulpevent_new(sizeof(struct sctp_adaptation_event),
648 MSG_NOTIFICATION, gfp);
649 if (!event)
650 goto fail;
651
652 skb = sctp_event2skb(event);
653 sai = skb_put(skb, sizeof(struct sctp_adaptation_event));
654
655 sai->sai_type = SCTP_ADAPTATION_INDICATION;
656 sai->sai_flags = 0;
657 sai->sai_length = sizeof(struct sctp_adaptation_event);
658 sai->sai_adaptation_ind = asoc->peer.adaptation_ind;
659 sctp_ulpevent_set_owner(event, asoc);
660 sai->sai_assoc_id = sctp_assoc2id(asoc);
661
662 return event;
663
664fail:
665 return NULL;
666}
667
668/* A message has been received. Package this message as a notification
669 * to pass it to the upper layers. Go ahead and calculate the sndrcvinfo
670 * even if filtered out later.
671 *
672 * Socket Extensions for SCTP
673 * 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
674 */
675struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc,
676 struct sctp_chunk *chunk,
677 gfp_t gfp)
678{
679 struct sctp_ulpevent *event = NULL;
680 struct sk_buff *skb = chunk->skb;
681 struct sock *sk = asoc->base.sk;
682 size_t padding, datalen;
683 int rx_count;
684
685 /*
686 * check to see if we need to make space for this
687 * new skb, expand the rcvbuffer if needed, or drop
688 * the frame
689 */
690 if (asoc->ep->rcvbuf_policy)
691 rx_count = atomic_read(&asoc->rmem_alloc);
692 else
693 rx_count = atomic_read(&sk->sk_rmem_alloc);
694
695 datalen = ntohs(chunk->chunk_hdr->length);
696
697 if (rx_count >= sk->sk_rcvbuf || !sk_rmem_schedule(sk, skb, datalen))
698 goto fail;
699
700 /* Clone the original skb, sharing the data. */
701 skb = skb_clone(chunk->skb, gfp);
702 if (!skb)
703 goto fail;
704
705 /* Now that all memory allocations for this chunk succeeded, we
706 * can mark it as received so the tsn_map is updated correctly.
707 */
708 if (sctp_tsnmap_mark(&asoc->peer.tsn_map,
709 ntohl(chunk->subh.data_hdr->tsn),
710 chunk->transport))
711 goto fail_mark;
712
713 /* First calculate the padding, so we don't inadvertently
714 * pass up the wrong length to the user.
715 *
716 * RFC 2960 - Section 3.2 Chunk Field Descriptions
717 *
718 * The total length of a chunk(including Type, Length and Value fields)
719 * MUST be a multiple of 4 bytes. If the length of the chunk is not a
720 * multiple of 4 bytes, the sender MUST pad the chunk with all zero
721 * bytes and this padding is not included in the chunk length field.
722 * The sender should never pad with more than 3 bytes. The receiver
723 * MUST ignore the padding bytes.
724 */
725 padding = SCTP_PAD4(datalen) - datalen;
726
727 /* Fixup cloned skb with just this chunks data. */
728 skb_trim(skb, chunk->chunk_end - padding - skb->data);
729
730 /* Embed the event fields inside the cloned skb. */
731 event = sctp_skb2event(skb);
732
733 /* Initialize event with flags 0 and correct length
734 * Since this is a clone of the original skb, only account for
735 * the data of this chunk as other chunks will be accounted separately.
736 */
737 sctp_ulpevent_init(event, 0, skb->len + sizeof(struct sk_buff));
738
739 /* And hold the chunk as we need it for getting the IP headers
740 * later in recvmsg
741 */
742 sctp_chunk_hold(chunk);
743 event->chunk = chunk;
744
745 sctp_ulpevent_receive_data(event, asoc);
746
747 event->stream = ntohs(chunk->subh.data_hdr->stream);
748 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
749 event->flags |= SCTP_UNORDERED;
750 event->cumtsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
751 }
752 event->tsn = ntohl(chunk->subh.data_hdr->tsn);
753 event->msg_flags |= chunk->chunk_hdr->flags;
754
755 return event;
756
757fail_mark:
758 kfree_skb(skb);
759fail:
760 return NULL;
761}
762
763/* Create a partial delivery related event.
764 *
765 * 5.3.1.7 SCTP_PARTIAL_DELIVERY_EVENT
766 *
767 * When a receiver is engaged in a partial delivery of a
768 * message this notification will be used to indicate
769 * various events.
770 */
771struct sctp_ulpevent *sctp_ulpevent_make_pdapi(
772 const struct sctp_association *asoc,
773 __u32 indication, __u32 sid, __u32 seq,
774 __u32 flags, gfp_t gfp)
775{
776 struct sctp_ulpevent *event;
777 struct sctp_pdapi_event *pd;
778 struct sk_buff *skb;
779
780 event = sctp_ulpevent_new(sizeof(struct sctp_pdapi_event),
781 MSG_NOTIFICATION, gfp);
782 if (!event)
783 goto fail;
784
785 skb = sctp_event2skb(event);
786 pd = skb_put(skb, sizeof(struct sctp_pdapi_event));
787
788 /* pdapi_type
789 * It should be SCTP_PARTIAL_DELIVERY_EVENT
790 *
791 * pdapi_flags: 16 bits (unsigned integer)
792 * Currently unused.
793 */
794 pd->pdapi_type = SCTP_PARTIAL_DELIVERY_EVENT;
795 pd->pdapi_flags = flags;
796 pd->pdapi_stream = sid;
797 pd->pdapi_seq = seq;
798
799 /* pdapi_length: 32 bits (unsigned integer)
800 *
801 * This field is the total length of the notification data, including
802 * the notification header. It will generally be sizeof (struct
803 * sctp_pdapi_event).
804 */
805 pd->pdapi_length = sizeof(struct sctp_pdapi_event);
806
807 /* pdapi_indication: 32 bits (unsigned integer)
808 *
809 * This field holds the indication being sent to the application.
810 */
811 pd->pdapi_indication = indication;
812
813 /* pdapi_assoc_id: sizeof (sctp_assoc_t)
814 *
815 * The association id field, holds the identifier for the association.
816 */
817 sctp_ulpevent_set_owner(event, asoc);
818 pd->pdapi_assoc_id = sctp_assoc2id(asoc);
819
820 return event;
821fail:
822 return NULL;
823}
824
825struct sctp_ulpevent *sctp_ulpevent_make_authkey(
826 const struct sctp_association *asoc, __u16 key_id,
827 __u32 indication, gfp_t gfp)
828{
829 struct sctp_ulpevent *event;
830 struct sctp_authkey_event *ak;
831 struct sk_buff *skb;
832
833 event = sctp_ulpevent_new(sizeof(struct sctp_authkey_event),
834 MSG_NOTIFICATION, gfp);
835 if (!event)
836 goto fail;
837
838 skb = sctp_event2skb(event);
839 ak = skb_put(skb, sizeof(struct sctp_authkey_event));
840
841 ak->auth_type = SCTP_AUTHENTICATION_EVENT;
842 ak->auth_flags = 0;
843 ak->auth_length = sizeof(struct sctp_authkey_event);
844
845 ak->auth_keynumber = key_id;
846 ak->auth_altkeynumber = 0;
847 ak->auth_indication = indication;
848
849 /*
850 * The association id field, holds the identifier for the association.
851 */
852 sctp_ulpevent_set_owner(event, asoc);
853 ak->auth_assoc_id = sctp_assoc2id(asoc);
854
855 return event;
856fail:
857 return NULL;
858}
859
860/*
861 * Socket Extensions for SCTP
862 * 6.3.10. SCTP_SENDER_DRY_EVENT
863 */
864struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event(
865 const struct sctp_association *asoc, gfp_t gfp)
866{
867 struct sctp_ulpevent *event;
868 struct sctp_sender_dry_event *sdry;
869 struct sk_buff *skb;
870
871 event = sctp_ulpevent_new(sizeof(struct sctp_sender_dry_event),
872 MSG_NOTIFICATION, gfp);
873 if (!event)
874 return NULL;
875
876 skb = sctp_event2skb(event);
877 sdry = skb_put(skb, sizeof(struct sctp_sender_dry_event));
878
879 sdry->sender_dry_type = SCTP_SENDER_DRY_EVENT;
880 sdry->sender_dry_flags = 0;
881 sdry->sender_dry_length = sizeof(struct sctp_sender_dry_event);
882 sctp_ulpevent_set_owner(event, asoc);
883 sdry->sender_dry_assoc_id = sctp_assoc2id(asoc);
884
885 return event;
886}
887
888struct sctp_ulpevent *sctp_ulpevent_make_stream_reset_event(
889 const struct sctp_association *asoc, __u16 flags, __u16 stream_num,
890 __be16 *stream_list, gfp_t gfp)
891{
892 struct sctp_stream_reset_event *sreset;
893 struct sctp_ulpevent *event;
894 struct sk_buff *skb;
895 int length, i;
896
897 length = sizeof(struct sctp_stream_reset_event) + 2 * stream_num;
898 event = sctp_ulpevent_new(length, MSG_NOTIFICATION, gfp);
899 if (!event)
900 return NULL;
901
902 skb = sctp_event2skb(event);
903 sreset = skb_put(skb, length);
904
905 sreset->strreset_type = SCTP_STREAM_RESET_EVENT;
906 sreset->strreset_flags = flags;
907 sreset->strreset_length = length;
908 sctp_ulpevent_set_owner(event, asoc);
909 sreset->strreset_assoc_id = sctp_assoc2id(asoc);
910
911 for (i = 0; i < stream_num; i++)
912 sreset->strreset_stream_list[i] = ntohs(stream_list[i]);
913
914 return event;
915}
916
917struct sctp_ulpevent *sctp_ulpevent_make_assoc_reset_event(
918 const struct sctp_association *asoc, __u16 flags, __u32 local_tsn,
919 __u32 remote_tsn, gfp_t gfp)
920{
921 struct sctp_assoc_reset_event *areset;
922 struct sctp_ulpevent *event;
923 struct sk_buff *skb;
924
925 event = sctp_ulpevent_new(sizeof(struct sctp_assoc_reset_event),
926 MSG_NOTIFICATION, gfp);
927 if (!event)
928 return NULL;
929
930 skb = sctp_event2skb(event);
931 areset = skb_put(skb, sizeof(struct sctp_assoc_reset_event));
932
933 areset->assocreset_type = SCTP_ASSOC_RESET_EVENT;
934 areset->assocreset_flags = flags;
935 areset->assocreset_length = sizeof(struct sctp_assoc_reset_event);
936 sctp_ulpevent_set_owner(event, asoc);
937 areset->assocreset_assoc_id = sctp_assoc2id(asoc);
938 areset->assocreset_local_tsn = local_tsn;
939 areset->assocreset_remote_tsn = remote_tsn;
940
941 return event;
942}
943
944struct sctp_ulpevent *sctp_ulpevent_make_stream_change_event(
945 const struct sctp_association *asoc, __u16 flags,
946 __u32 strchange_instrms, __u32 strchange_outstrms, gfp_t gfp)
947{
948 struct sctp_stream_change_event *schange;
949 struct sctp_ulpevent *event;
950 struct sk_buff *skb;
951
952 event = sctp_ulpevent_new(sizeof(struct sctp_stream_change_event),
953 MSG_NOTIFICATION, gfp);
954 if (!event)
955 return NULL;
956
957 skb = sctp_event2skb(event);
958 schange = skb_put(skb, sizeof(struct sctp_stream_change_event));
959
960 schange->strchange_type = SCTP_STREAM_CHANGE_EVENT;
961 schange->strchange_flags = flags;
962 schange->strchange_length = sizeof(struct sctp_stream_change_event);
963 sctp_ulpevent_set_owner(event, asoc);
964 schange->strchange_assoc_id = sctp_assoc2id(asoc);
965 schange->strchange_instrms = strchange_instrms;
966 schange->strchange_outstrms = strchange_outstrms;
967
968 return event;
969}
970
971/* Return the notification type, assuming this is a notification
972 * event.
973 */
974__u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event)
975{
976 union sctp_notification *notification;
977 struct sk_buff *skb;
978
979 skb = sctp_event2skb(event);
980 notification = (union sctp_notification *) skb->data;
981 return notification->sn_header.sn_type;
982}
983
984/* RFC6458, Section 5.3.2. SCTP Header Information Structure
985 * (SCTP_SNDRCV, DEPRECATED)
986 */
987void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
988 struct msghdr *msghdr)
989{
990 struct sctp_sndrcvinfo sinfo;
991
992 if (sctp_ulpevent_is_notification(event))
993 return;
994
995 memset(&sinfo, 0, sizeof(sinfo));
996 sinfo.sinfo_stream = event->stream;
997 sinfo.sinfo_ssn = event->ssn;
998 sinfo.sinfo_ppid = event->ppid;
999 sinfo.sinfo_flags = event->flags;
1000 sinfo.sinfo_tsn = event->tsn;
1001 sinfo.sinfo_cumtsn = event->cumtsn;
1002 sinfo.sinfo_assoc_id = sctp_assoc2id(event->asoc);
1003 /* Context value that is set via SCTP_CONTEXT socket option. */
1004 sinfo.sinfo_context = event->asoc->default_rcv_context;
1005 /* These fields are not used while receiving. */
1006 sinfo.sinfo_timetolive = 0;
1007
1008 put_cmsg(msghdr, IPPROTO_SCTP, SCTP_SNDRCV,
1009 sizeof(sinfo), &sinfo);
1010}
1011
1012/* RFC6458, Section 5.3.5 SCTP Receive Information Structure
1013 * (SCTP_SNDRCV)
1014 */
1015void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event,
1016 struct msghdr *msghdr)
1017{
1018 struct sctp_rcvinfo rinfo;
1019
1020 if (sctp_ulpevent_is_notification(event))
1021 return;
1022
1023 memset(&rinfo, 0, sizeof(struct sctp_rcvinfo));
1024 rinfo.rcv_sid = event->stream;
1025 rinfo.rcv_ssn = event->ssn;
1026 rinfo.rcv_ppid = event->ppid;
1027 rinfo.rcv_flags = event->flags;
1028 rinfo.rcv_tsn = event->tsn;
1029 rinfo.rcv_cumtsn = event->cumtsn;
1030 rinfo.rcv_assoc_id = sctp_assoc2id(event->asoc);
1031 rinfo.rcv_context = event->asoc->default_rcv_context;
1032
1033 put_cmsg(msghdr, IPPROTO_SCTP, SCTP_RCVINFO,
1034 sizeof(rinfo), &rinfo);
1035}
1036
1037/* RFC6458, Section 5.3.6. SCTP Next Receive Information Structure
1038 * (SCTP_NXTINFO)
1039 */
1040static void __sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
1041 struct msghdr *msghdr,
1042 const struct sk_buff *skb)
1043{
1044 struct sctp_nxtinfo nxtinfo;
1045
1046 memset(&nxtinfo, 0, sizeof(nxtinfo));
1047 nxtinfo.nxt_sid = event->stream;
1048 nxtinfo.nxt_ppid = event->ppid;
1049 nxtinfo.nxt_flags = event->flags;
1050 if (sctp_ulpevent_is_notification(event))
1051 nxtinfo.nxt_flags |= SCTP_NOTIFICATION;
1052 nxtinfo.nxt_length = skb->len;
1053 nxtinfo.nxt_assoc_id = sctp_assoc2id(event->asoc);
1054
1055 put_cmsg(msghdr, IPPROTO_SCTP, SCTP_NXTINFO,
1056 sizeof(nxtinfo), &nxtinfo);
1057}
1058
1059void sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
1060 struct msghdr *msghdr,
1061 struct sock *sk)
1062{
1063 struct sk_buff *skb;
1064 int err;
1065
1066 skb = sctp_skb_recv_datagram(sk, MSG_PEEK | MSG_DONTWAIT, &err);
1067 if (skb != NULL) {
1068 __sctp_ulpevent_read_nxtinfo(sctp_skb2event(skb),
1069 msghdr, skb);
1070 /* Just release refcount here. */
1071 kfree_skb(skb);
1072 }
1073}
1074
1075/* Do accounting for bytes received and hold a reference to the association
1076 * for each skb.
1077 */
1078static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
1079 struct sctp_association *asoc)
1080{
1081 struct sk_buff *skb, *frag;
1082
1083 skb = sctp_event2skb(event);
1084 /* Set the owner and charge rwnd for bytes received. */
1085 sctp_ulpevent_set_owner(event, asoc);
1086 sctp_assoc_rwnd_decrease(asoc, skb_headlen(skb));
1087
1088 if (!skb->data_len)
1089 return;
1090
1091 /* Note: Not clearing the entire event struct as this is just a
1092 * fragment of the real event. However, we still need to do rwnd
1093 * accounting.
1094 * In general, the skb passed from IP can have only 1 level of
1095 * fragments. But we allow multiple levels of fragments.
1096 */
1097 skb_walk_frags(skb, frag)
1098 sctp_ulpevent_receive_data(sctp_skb2event(frag), asoc);
1099}
1100
1101/* Do accounting for bytes just read by user and release the references to
1102 * the association.
1103 */
1104static void sctp_ulpevent_release_data(struct sctp_ulpevent *event)
1105{
1106 struct sk_buff *skb, *frag;
1107 unsigned int len;
1108
1109 /* Current stack structures assume that the rcv buffer is
1110 * per socket. For UDP style sockets this is not true as
1111 * multiple associations may be on a single UDP-style socket.
1112 * Use the local private area of the skb to track the owning
1113 * association.
1114 */
1115
1116 skb = sctp_event2skb(event);
1117 len = skb->len;
1118
1119 if (!skb->data_len)
1120 goto done;
1121
1122 /* Don't forget the fragments. */
1123 skb_walk_frags(skb, frag) {
1124 /* NOTE: skb_shinfos are recursive. Although IP returns
1125 * skb's with only 1 level of fragments, SCTP reassembly can
1126 * increase the levels.
1127 */
1128 sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
1129 }
1130
1131done:
1132 sctp_assoc_rwnd_increase(event->asoc, len);
1133 sctp_chunk_put(event->chunk);
1134 sctp_ulpevent_release_owner(event);
1135}
1136
1137static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event)
1138{
1139 struct sk_buff *skb, *frag;
1140
1141 skb = sctp_event2skb(event);
1142
1143 if (!skb->data_len)
1144 goto done;
1145
1146 /* Don't forget the fragments. */
1147 skb_walk_frags(skb, frag) {
1148 /* NOTE: skb_shinfos are recursive. Although IP returns
1149 * skb's with only 1 level of fragments, SCTP reassembly can
1150 * increase the levels.
1151 */
1152 sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
1153 }
1154
1155done:
1156 sctp_chunk_put(event->chunk);
1157 sctp_ulpevent_release_owner(event);
1158}
1159
1160/* Free a ulpevent that has an owner. It includes releasing the reference
1161 * to the owner, updating the rwnd in case of a DATA event and freeing the
1162 * skb.
1163 */
1164void sctp_ulpevent_free(struct sctp_ulpevent *event)
1165{
1166 if (sctp_ulpevent_is_notification(event))
1167 sctp_ulpevent_release_owner(event);
1168 else
1169 sctp_ulpevent_release_data(event);
1170
1171 kfree_skb(sctp_event2skb(event));
1172}
1173
1174/* Purge the skb lists holding ulpevents. */
1175unsigned int sctp_queue_purge_ulpevents(struct sk_buff_head *list)
1176{
1177 struct sk_buff *skb;
1178 unsigned int data_unread = 0;
1179
1180 while ((skb = skb_dequeue(list)) != NULL) {
1181 struct sctp_ulpevent *event = sctp_skb2event(skb);
1182
1183 if (!sctp_ulpevent_is_notification(event))
1184 data_unread += skb->len;
1185
1186 sctp_ulpevent_free(event);
1187 }
1188
1189 return data_unread;
1190}
1/* SCTP kernel implementation
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 * These functions manipulate an sctp event. The struct ulpevent is used
10 * to carry notifications and data to the ULP (sockets).
11 *
12 * This SCTP implementation is free software;
13 * you can redistribute it and/or modify it under the terms of
14 * the GNU General Public License as published by
15 * the Free Software Foundation; either version 2, or (at your option)
16 * any later version.
17 *
18 * This SCTP implementation is distributed in the hope that it
19 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
20 * ************************
21 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22 * See the GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with GNU CC; see the file COPYING. If not, write to
26 * the Free Software Foundation, 59 Temple Place - Suite 330,
27 * Boston, MA 02111-1307, USA.
28 *
29 * Please send any bug reports or fixes you make to the
30 * email address(es):
31 * lksctp developers <lksctp-developers@lists.sourceforge.net>
32 *
33 * Or submit a bug report through the following website:
34 * http://www.sf.net/projects/lksctp
35 *
36 * Written or modified by:
37 * Jon Grimm <jgrimm@us.ibm.com>
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Ardelle Fan <ardelle.fan@intel.com>
40 * Sridhar Samudrala <sri@us.ibm.com>
41 *
42 * Any bugs reported given to us we will try to fix... any fixes shared will
43 * be incorporated into the next SCTP release.
44 */
45
46#include <linux/slab.h>
47#include <linux/types.h>
48#include <linux/skbuff.h>
49#include <net/sctp/structs.h>
50#include <net/sctp/sctp.h>
51#include <net/sctp/sm.h>
52
53static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
54 struct sctp_association *asoc);
55static void sctp_ulpevent_release_data(struct sctp_ulpevent *event);
56static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event);
57
58
59/* Initialize an ULP event from an given skb. */
60SCTP_STATIC void sctp_ulpevent_init(struct sctp_ulpevent *event,
61 int msg_flags,
62 unsigned int len)
63{
64 memset(event, 0, sizeof(struct sctp_ulpevent));
65 event->msg_flags = msg_flags;
66 event->rmem_len = len;
67}
68
69/* Create a new sctp_ulpevent. */
70SCTP_STATIC struct sctp_ulpevent *sctp_ulpevent_new(int size, int msg_flags,
71 gfp_t gfp)
72{
73 struct sctp_ulpevent *event;
74 struct sk_buff *skb;
75
76 skb = alloc_skb(size, gfp);
77 if (!skb)
78 goto fail;
79
80 event = sctp_skb2event(skb);
81 sctp_ulpevent_init(event, msg_flags, skb->truesize);
82
83 return event;
84
85fail:
86 return NULL;
87}
88
89/* Is this a MSG_NOTIFICATION? */
90int sctp_ulpevent_is_notification(const struct sctp_ulpevent *event)
91{
92 return MSG_NOTIFICATION == (event->msg_flags & MSG_NOTIFICATION);
93}
94
95/* Hold the association in case the msg_name needs read out of
96 * the association.
97 */
98static inline void sctp_ulpevent_set_owner(struct sctp_ulpevent *event,
99 const struct sctp_association *asoc)
100{
101 struct sk_buff *skb;
102
103 /* Cast away the const, as we are just wanting to
104 * bump the reference count.
105 */
106 sctp_association_hold((struct sctp_association *)asoc);
107 skb = sctp_event2skb(event);
108 event->asoc = (struct sctp_association *)asoc;
109 atomic_add(event->rmem_len, &event->asoc->rmem_alloc);
110 sctp_skb_set_owner_r(skb, asoc->base.sk);
111}
112
113/* A simple destructor to give up the reference to the association. */
114static inline void sctp_ulpevent_release_owner(struct sctp_ulpevent *event)
115{
116 struct sctp_association *asoc = event->asoc;
117
118 atomic_sub(event->rmem_len, &asoc->rmem_alloc);
119 sctp_association_put(asoc);
120}
121
122/* Create and initialize an SCTP_ASSOC_CHANGE event.
123 *
124 * 5.3.1.1 SCTP_ASSOC_CHANGE
125 *
126 * Communication notifications inform the ULP that an SCTP association
127 * has either begun or ended. The identifier for a new association is
128 * provided by this notification.
129 *
130 * Note: There is no field checking here. If a field is unused it will be
131 * zero'd out.
132 */
133struct sctp_ulpevent *sctp_ulpevent_make_assoc_change(
134 const struct sctp_association *asoc,
135 __u16 flags, __u16 state, __u16 error, __u16 outbound,
136 __u16 inbound, struct sctp_chunk *chunk, gfp_t gfp)
137{
138 struct sctp_ulpevent *event;
139 struct sctp_assoc_change *sac;
140 struct sk_buff *skb;
141
142 /* If the lower layer passed in the chunk, it will be
143 * an ABORT, so we need to include it in the sac_info.
144 */
145 if (chunk) {
146 /* Copy the chunk data to a new skb and reserve enough
147 * head room to use as notification.
148 */
149 skb = skb_copy_expand(chunk->skb,
150 sizeof(struct sctp_assoc_change), 0, gfp);
151
152 if (!skb)
153 goto fail;
154
155 /* Embed the event fields inside the cloned skb. */
156 event = sctp_skb2event(skb);
157 sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
158
159 /* Include the notification structure */
160 sac = (struct sctp_assoc_change *)
161 skb_push(skb, sizeof(struct sctp_assoc_change));
162
163 /* Trim the buffer to the right length. */
164 skb_trim(skb, sizeof(struct sctp_assoc_change) +
165 ntohs(chunk->chunk_hdr->length) -
166 sizeof(sctp_chunkhdr_t));
167 } else {
168 event = sctp_ulpevent_new(sizeof(struct sctp_assoc_change),
169 MSG_NOTIFICATION, gfp);
170 if (!event)
171 goto fail;
172
173 skb = sctp_event2skb(event);
174 sac = (struct sctp_assoc_change *) skb_put(skb,
175 sizeof(struct sctp_assoc_change));
176 }
177
178 /* Socket Extensions for SCTP
179 * 5.3.1.1 SCTP_ASSOC_CHANGE
180 *
181 * sac_type:
182 * It should be SCTP_ASSOC_CHANGE.
183 */
184 sac->sac_type = SCTP_ASSOC_CHANGE;
185
186 /* Socket Extensions for SCTP
187 * 5.3.1.1 SCTP_ASSOC_CHANGE
188 *
189 * sac_state: 32 bits (signed integer)
190 * This field holds one of a number of values that communicate the
191 * event that happened to the association.
192 */
193 sac->sac_state = state;
194
195 /* Socket Extensions for SCTP
196 * 5.3.1.1 SCTP_ASSOC_CHANGE
197 *
198 * sac_flags: 16 bits (unsigned integer)
199 * Currently unused.
200 */
201 sac->sac_flags = 0;
202
203 /* Socket Extensions for SCTP
204 * 5.3.1.1 SCTP_ASSOC_CHANGE
205 *
206 * sac_length: sizeof (__u32)
207 * This field is the total length of the notification data, including
208 * the notification header.
209 */
210 sac->sac_length = skb->len;
211
212 /* Socket Extensions for SCTP
213 * 5.3.1.1 SCTP_ASSOC_CHANGE
214 *
215 * sac_error: 32 bits (signed integer)
216 *
217 * If the state was reached due to a error condition (e.g.
218 * COMMUNICATION_LOST) any relevant error information is available in
219 * this field. This corresponds to the protocol error codes defined in
220 * [SCTP].
221 */
222 sac->sac_error = error;
223
224 /* Socket Extensions for SCTP
225 * 5.3.1.1 SCTP_ASSOC_CHANGE
226 *
227 * sac_outbound_streams: 16 bits (unsigned integer)
228 * sac_inbound_streams: 16 bits (unsigned integer)
229 *
230 * The maximum number of streams allowed in each direction are
231 * available in sac_outbound_streams and sac_inbound streams.
232 */
233 sac->sac_outbound_streams = outbound;
234 sac->sac_inbound_streams = inbound;
235
236 /* Socket Extensions for SCTP
237 * 5.3.1.1 SCTP_ASSOC_CHANGE
238 *
239 * sac_assoc_id: sizeof (sctp_assoc_t)
240 *
241 * The association id field, holds the identifier for the association.
242 * All notifications for a given association have the same association
243 * identifier. For TCP style socket, this field is ignored.
244 */
245 sctp_ulpevent_set_owner(event, asoc);
246 sac->sac_assoc_id = sctp_assoc2id(asoc);
247
248 return event;
249
250fail:
251 return NULL;
252}
253
254/* Create and initialize an SCTP_PEER_ADDR_CHANGE event.
255 *
256 * Socket Extensions for SCTP - draft-01
257 * 5.3.1.2 SCTP_PEER_ADDR_CHANGE
258 *
259 * When a destination address on a multi-homed peer encounters a change
260 * an interface details event is sent.
261 */
262struct sctp_ulpevent *sctp_ulpevent_make_peer_addr_change(
263 const struct sctp_association *asoc,
264 const struct sockaddr_storage *aaddr,
265 int flags, int state, int error, gfp_t gfp)
266{
267 struct sctp_ulpevent *event;
268 struct sctp_paddr_change *spc;
269 struct sk_buff *skb;
270
271 event = sctp_ulpevent_new(sizeof(struct sctp_paddr_change),
272 MSG_NOTIFICATION, gfp);
273 if (!event)
274 goto fail;
275
276 skb = sctp_event2skb(event);
277 spc = (struct sctp_paddr_change *)
278 skb_put(skb, sizeof(struct sctp_paddr_change));
279
280 /* Sockets API Extensions for SCTP
281 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
282 *
283 * spc_type:
284 *
285 * It should be SCTP_PEER_ADDR_CHANGE.
286 */
287 spc->spc_type = SCTP_PEER_ADDR_CHANGE;
288
289 /* Sockets API Extensions for SCTP
290 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
291 *
292 * spc_length: sizeof (__u32)
293 *
294 * This field is the total length of the notification data, including
295 * the notification header.
296 */
297 spc->spc_length = sizeof(struct sctp_paddr_change);
298
299 /* Sockets API Extensions for SCTP
300 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
301 *
302 * spc_flags: 16 bits (unsigned integer)
303 * Currently unused.
304 */
305 spc->spc_flags = 0;
306
307 /* Sockets API Extensions for SCTP
308 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
309 *
310 * spc_state: 32 bits (signed integer)
311 *
312 * This field holds one of a number of values that communicate the
313 * event that happened to the address.
314 */
315 spc->spc_state = state;
316
317 /* Sockets API Extensions for SCTP
318 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
319 *
320 * spc_error: 32 bits (signed integer)
321 *
322 * If the state was reached due to any error condition (e.g.
323 * ADDRESS_UNREACHABLE) any relevant error information is available in
324 * this field.
325 */
326 spc->spc_error = error;
327
328 /* Socket Extensions for SCTP
329 * 5.3.1.1 SCTP_ASSOC_CHANGE
330 *
331 * spc_assoc_id: sizeof (sctp_assoc_t)
332 *
333 * The association id field, holds the identifier for the association.
334 * All notifications for a given association have the same association
335 * identifier. For TCP style socket, this field is ignored.
336 */
337 sctp_ulpevent_set_owner(event, asoc);
338 spc->spc_assoc_id = sctp_assoc2id(asoc);
339
340 /* Sockets API Extensions for SCTP
341 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
342 *
343 * spc_aaddr: sizeof (struct sockaddr_storage)
344 *
345 * The affected address field, holds the remote peer's address that is
346 * encountering the change of state.
347 */
348 memcpy(&spc->spc_aaddr, aaddr, sizeof(struct sockaddr_storage));
349
350 /* Map ipv4 address into v4-mapped-on-v6 address. */
351 sctp_get_pf_specific(asoc->base.sk->sk_family)->addr_v4map(
352 sctp_sk(asoc->base.sk),
353 (union sctp_addr *)&spc->spc_aaddr);
354
355 return event;
356
357fail:
358 return NULL;
359}
360
361/* Create and initialize an SCTP_REMOTE_ERROR notification.
362 *
363 * Note: This assumes that the chunk->skb->data already points to the
364 * operation error payload.
365 *
366 * Socket Extensions for SCTP - draft-01
367 * 5.3.1.3 SCTP_REMOTE_ERROR
368 *
369 * A remote peer may send an Operational Error message to its peer.
370 * This message indicates a variety of error conditions on an
371 * association. The entire error TLV as it appears on the wire is
372 * included in a SCTP_REMOTE_ERROR event. Please refer to the SCTP
373 * specification [SCTP] and any extensions for a list of possible
374 * error formats.
375 */
376struct sctp_ulpevent *sctp_ulpevent_make_remote_error(
377 const struct sctp_association *asoc, struct sctp_chunk *chunk,
378 __u16 flags, gfp_t gfp)
379{
380 struct sctp_ulpevent *event;
381 struct sctp_remote_error *sre;
382 struct sk_buff *skb;
383 sctp_errhdr_t *ch;
384 __be16 cause;
385 int elen;
386
387 ch = (sctp_errhdr_t *)(chunk->skb->data);
388 cause = ch->cause;
389 elen = WORD_ROUND(ntohs(ch->length)) - sizeof(sctp_errhdr_t);
390
391 /* Pull off the ERROR header. */
392 skb_pull(chunk->skb, sizeof(sctp_errhdr_t));
393
394 /* Copy the skb to a new skb with room for us to prepend
395 * notification with.
396 */
397 skb = skb_copy_expand(chunk->skb, sizeof(struct sctp_remote_error),
398 0, gfp);
399
400 /* Pull off the rest of the cause TLV from the chunk. */
401 skb_pull(chunk->skb, elen);
402 if (!skb)
403 goto fail;
404
405 /* Embed the event fields inside the cloned skb. */
406 event = sctp_skb2event(skb);
407 sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
408
409 sre = (struct sctp_remote_error *)
410 skb_push(skb, sizeof(struct sctp_remote_error));
411
412 /* Trim the buffer to the right length. */
413 skb_trim(skb, sizeof(struct sctp_remote_error) + elen);
414
415 /* Socket Extensions for SCTP
416 * 5.3.1.3 SCTP_REMOTE_ERROR
417 *
418 * sre_type:
419 * It should be SCTP_REMOTE_ERROR.
420 */
421 sre->sre_type = SCTP_REMOTE_ERROR;
422
423 /*
424 * Socket Extensions for SCTP
425 * 5.3.1.3 SCTP_REMOTE_ERROR
426 *
427 * sre_flags: 16 bits (unsigned integer)
428 * Currently unused.
429 */
430 sre->sre_flags = 0;
431
432 /* Socket Extensions for SCTP
433 * 5.3.1.3 SCTP_REMOTE_ERROR
434 *
435 * sre_length: sizeof (__u32)
436 *
437 * This field is the total length of the notification data,
438 * including the notification header.
439 */
440 sre->sre_length = skb->len;
441
442 /* Socket Extensions for SCTP
443 * 5.3.1.3 SCTP_REMOTE_ERROR
444 *
445 * sre_error: 16 bits (unsigned integer)
446 * This value represents one of the Operational Error causes defined in
447 * the SCTP specification, in network byte order.
448 */
449 sre->sre_error = cause;
450
451 /* Socket Extensions for SCTP
452 * 5.3.1.3 SCTP_REMOTE_ERROR
453 *
454 * sre_assoc_id: sizeof (sctp_assoc_t)
455 *
456 * The association id field, holds the identifier for the association.
457 * All notifications for a given association have the same association
458 * identifier. For TCP style socket, this field is ignored.
459 */
460 sctp_ulpevent_set_owner(event, asoc);
461 sre->sre_assoc_id = sctp_assoc2id(asoc);
462
463 return event;
464
465fail:
466 return NULL;
467}
468
469/* Create and initialize a SCTP_SEND_FAILED notification.
470 *
471 * Socket Extensions for SCTP - draft-01
472 * 5.3.1.4 SCTP_SEND_FAILED
473 */
474struct sctp_ulpevent *sctp_ulpevent_make_send_failed(
475 const struct sctp_association *asoc, struct sctp_chunk *chunk,
476 __u16 flags, __u32 error, gfp_t gfp)
477{
478 struct sctp_ulpevent *event;
479 struct sctp_send_failed *ssf;
480 struct sk_buff *skb;
481
482 /* Pull off any padding. */
483 int len = ntohs(chunk->chunk_hdr->length);
484
485 /* Make skb with more room so we can prepend notification. */
486 skb = skb_copy_expand(chunk->skb,
487 sizeof(struct sctp_send_failed), /* headroom */
488 0, /* tailroom */
489 gfp);
490 if (!skb)
491 goto fail;
492
493 /* Pull off the common chunk header and DATA header. */
494 skb_pull(skb, sizeof(struct sctp_data_chunk));
495 len -= sizeof(struct sctp_data_chunk);
496
497 /* Embed the event fields inside the cloned skb. */
498 event = sctp_skb2event(skb);
499 sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
500
501 ssf = (struct sctp_send_failed *)
502 skb_push(skb, sizeof(struct sctp_send_failed));
503
504 /* Socket Extensions for SCTP
505 * 5.3.1.4 SCTP_SEND_FAILED
506 *
507 * ssf_type:
508 * It should be SCTP_SEND_FAILED.
509 */
510 ssf->ssf_type = SCTP_SEND_FAILED;
511
512 /* Socket Extensions for SCTP
513 * 5.3.1.4 SCTP_SEND_FAILED
514 *
515 * ssf_flags: 16 bits (unsigned integer)
516 * The flag value will take one of the following values
517 *
518 * SCTP_DATA_UNSENT - Indicates that the data was never put on
519 * the wire.
520 *
521 * SCTP_DATA_SENT - Indicates that the data was put on the wire.
522 * Note that this does not necessarily mean that the
523 * data was (or was not) successfully delivered.
524 */
525 ssf->ssf_flags = flags;
526
527 /* Socket Extensions for SCTP
528 * 5.3.1.4 SCTP_SEND_FAILED
529 *
530 * ssf_length: sizeof (__u32)
531 * This field is the total length of the notification data, including
532 * the notification header.
533 */
534 ssf->ssf_length = sizeof(struct sctp_send_failed) + len;
535 skb_trim(skb, ssf->ssf_length);
536
537 /* Socket Extensions for SCTP
538 * 5.3.1.4 SCTP_SEND_FAILED
539 *
540 * ssf_error: 16 bits (unsigned integer)
541 * This value represents the reason why the send failed, and if set,
542 * will be a SCTP protocol error code as defined in [SCTP] section
543 * 3.3.10.
544 */
545 ssf->ssf_error = error;
546
547 /* Socket Extensions for SCTP
548 * 5.3.1.4 SCTP_SEND_FAILED
549 *
550 * ssf_info: sizeof (struct sctp_sndrcvinfo)
551 * The original send information associated with the undelivered
552 * message.
553 */
554 memcpy(&ssf->ssf_info, &chunk->sinfo, sizeof(struct sctp_sndrcvinfo));
555
556 /* Per TSVWG discussion with Randy. Allow the application to
557 * reassemble a fragmented message.
558 */
559 ssf->ssf_info.sinfo_flags = chunk->chunk_hdr->flags;
560
561 /* Socket Extensions for SCTP
562 * 5.3.1.4 SCTP_SEND_FAILED
563 *
564 * ssf_assoc_id: sizeof (sctp_assoc_t)
565 * The association id field, sf_assoc_id, holds the identifier for the
566 * association. All notifications for a given association have the
567 * same association identifier. For TCP style socket, this field is
568 * ignored.
569 */
570 sctp_ulpevent_set_owner(event, asoc);
571 ssf->ssf_assoc_id = sctp_assoc2id(asoc);
572 return event;
573
574fail:
575 return NULL;
576}
577
578/* Create and initialize a SCTP_SHUTDOWN_EVENT notification.
579 *
580 * Socket Extensions for SCTP - draft-01
581 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
582 */
583struct sctp_ulpevent *sctp_ulpevent_make_shutdown_event(
584 const struct sctp_association *asoc,
585 __u16 flags, gfp_t gfp)
586{
587 struct sctp_ulpevent *event;
588 struct sctp_shutdown_event *sse;
589 struct sk_buff *skb;
590
591 event = sctp_ulpevent_new(sizeof(struct sctp_shutdown_event),
592 MSG_NOTIFICATION, gfp);
593 if (!event)
594 goto fail;
595
596 skb = sctp_event2skb(event);
597 sse = (struct sctp_shutdown_event *)
598 skb_put(skb, sizeof(struct sctp_shutdown_event));
599
600 /* Socket Extensions for SCTP
601 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
602 *
603 * sse_type
604 * It should be SCTP_SHUTDOWN_EVENT
605 */
606 sse->sse_type = SCTP_SHUTDOWN_EVENT;
607
608 /* Socket Extensions for SCTP
609 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
610 *
611 * sse_flags: 16 bits (unsigned integer)
612 * Currently unused.
613 */
614 sse->sse_flags = 0;
615
616 /* Socket Extensions for SCTP
617 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
618 *
619 * sse_length: sizeof (__u32)
620 * This field is the total length of the notification data, including
621 * the notification header.
622 */
623 sse->sse_length = sizeof(struct sctp_shutdown_event);
624
625 /* Socket Extensions for SCTP
626 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
627 *
628 * sse_assoc_id: sizeof (sctp_assoc_t)
629 * The association id field, holds the identifier for the association.
630 * All notifications for a given association have the same association
631 * identifier. For TCP style socket, this field is ignored.
632 */
633 sctp_ulpevent_set_owner(event, asoc);
634 sse->sse_assoc_id = sctp_assoc2id(asoc);
635
636 return event;
637
638fail:
639 return NULL;
640}
641
642/* Create and initialize a SCTP_ADAPTATION_INDICATION notification.
643 *
644 * Socket Extensions for SCTP
645 * 5.3.1.6 SCTP_ADAPTATION_INDICATION
646 */
647struct sctp_ulpevent *sctp_ulpevent_make_adaptation_indication(
648 const struct sctp_association *asoc, gfp_t gfp)
649{
650 struct sctp_ulpevent *event;
651 struct sctp_adaptation_event *sai;
652 struct sk_buff *skb;
653
654 event = sctp_ulpevent_new(sizeof(struct sctp_adaptation_event),
655 MSG_NOTIFICATION, gfp);
656 if (!event)
657 goto fail;
658
659 skb = sctp_event2skb(event);
660 sai = (struct sctp_adaptation_event *)
661 skb_put(skb, sizeof(struct sctp_adaptation_event));
662
663 sai->sai_type = SCTP_ADAPTATION_INDICATION;
664 sai->sai_flags = 0;
665 sai->sai_length = sizeof(struct sctp_adaptation_event);
666 sai->sai_adaptation_ind = asoc->peer.adaptation_ind;
667 sctp_ulpevent_set_owner(event, asoc);
668 sai->sai_assoc_id = sctp_assoc2id(asoc);
669
670 return event;
671
672fail:
673 return NULL;
674}
675
676/* A message has been received. Package this message as a notification
677 * to pass it to the upper layers. Go ahead and calculate the sndrcvinfo
678 * even if filtered out later.
679 *
680 * Socket Extensions for SCTP
681 * 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
682 */
683struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc,
684 struct sctp_chunk *chunk,
685 gfp_t gfp)
686{
687 struct sctp_ulpevent *event = NULL;
688 struct sk_buff *skb;
689 size_t padding, len;
690 int rx_count;
691
692 /*
693 * check to see if we need to make space for this
694 * new skb, expand the rcvbuffer if needed, or drop
695 * the frame
696 */
697 if (asoc->ep->rcvbuf_policy)
698 rx_count = atomic_read(&asoc->rmem_alloc);
699 else
700 rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
701
702 if (rx_count >= asoc->base.sk->sk_rcvbuf) {
703
704 if ((asoc->base.sk->sk_userlocks & SOCK_RCVBUF_LOCK) ||
705 (!sk_rmem_schedule(asoc->base.sk, chunk->skb->truesize)))
706 goto fail;
707 }
708
709 /* Clone the original skb, sharing the data. */
710 skb = skb_clone(chunk->skb, gfp);
711 if (!skb)
712 goto fail;
713
714 /* Now that all memory allocations for this chunk succeeded, we
715 * can mark it as received so the tsn_map is updated correctly.
716 */
717 if (sctp_tsnmap_mark(&asoc->peer.tsn_map,
718 ntohl(chunk->subh.data_hdr->tsn),
719 chunk->transport))
720 goto fail_mark;
721
722 /* First calculate the padding, so we don't inadvertently
723 * pass up the wrong length to the user.
724 *
725 * RFC 2960 - Section 3.2 Chunk Field Descriptions
726 *
727 * The total length of a chunk(including Type, Length and Value fields)
728 * MUST be a multiple of 4 bytes. If the length of the chunk is not a
729 * multiple of 4 bytes, the sender MUST pad the chunk with all zero
730 * bytes and this padding is not included in the chunk length field.
731 * The sender should never pad with more than 3 bytes. The receiver
732 * MUST ignore the padding bytes.
733 */
734 len = ntohs(chunk->chunk_hdr->length);
735 padding = WORD_ROUND(len) - len;
736
737 /* Fixup cloned skb with just this chunks data. */
738 skb_trim(skb, chunk->chunk_end - padding - skb->data);
739
740 /* Embed the event fields inside the cloned skb. */
741 event = sctp_skb2event(skb);
742
743 /* Initialize event with flags 0 and correct length
744 * Since this is a clone of the original skb, only account for
745 * the data of this chunk as other chunks will be accounted separately.
746 */
747 sctp_ulpevent_init(event, 0, skb->len + sizeof(struct sk_buff));
748
749 sctp_ulpevent_receive_data(event, asoc);
750
751 event->stream = ntohs(chunk->subh.data_hdr->stream);
752 event->ssn = ntohs(chunk->subh.data_hdr->ssn);
753 event->ppid = chunk->subh.data_hdr->ppid;
754 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
755 event->flags |= SCTP_UNORDERED;
756 event->cumtsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
757 }
758 event->tsn = ntohl(chunk->subh.data_hdr->tsn);
759 event->msg_flags |= chunk->chunk_hdr->flags;
760 event->iif = sctp_chunk_iif(chunk);
761
762 return event;
763
764fail_mark:
765 kfree_skb(skb);
766fail:
767 return NULL;
768}
769
770/* Create a partial delivery related event.
771 *
772 * 5.3.1.7 SCTP_PARTIAL_DELIVERY_EVENT
773 *
774 * When a receiver is engaged in a partial delivery of a
775 * message this notification will be used to indicate
776 * various events.
777 */
778struct sctp_ulpevent *sctp_ulpevent_make_pdapi(
779 const struct sctp_association *asoc, __u32 indication,
780 gfp_t gfp)
781{
782 struct sctp_ulpevent *event;
783 struct sctp_pdapi_event *pd;
784 struct sk_buff *skb;
785
786 event = sctp_ulpevent_new(sizeof(struct sctp_pdapi_event),
787 MSG_NOTIFICATION, gfp);
788 if (!event)
789 goto fail;
790
791 skb = sctp_event2skb(event);
792 pd = (struct sctp_pdapi_event *)
793 skb_put(skb, sizeof(struct sctp_pdapi_event));
794
795 /* pdapi_type
796 * It should be SCTP_PARTIAL_DELIVERY_EVENT
797 *
798 * pdapi_flags: 16 bits (unsigned integer)
799 * Currently unused.
800 */
801 pd->pdapi_type = SCTP_PARTIAL_DELIVERY_EVENT;
802 pd->pdapi_flags = 0;
803
804 /* pdapi_length: 32 bits (unsigned integer)
805 *
806 * This field is the total length of the notification data, including
807 * the notification header. It will generally be sizeof (struct
808 * sctp_pdapi_event).
809 */
810 pd->pdapi_length = sizeof(struct sctp_pdapi_event);
811
812 /* pdapi_indication: 32 bits (unsigned integer)
813 *
814 * This field holds the indication being sent to the application.
815 */
816 pd->pdapi_indication = indication;
817
818 /* pdapi_assoc_id: sizeof (sctp_assoc_t)
819 *
820 * The association id field, holds the identifier for the association.
821 */
822 sctp_ulpevent_set_owner(event, asoc);
823 pd->pdapi_assoc_id = sctp_assoc2id(asoc);
824
825 return event;
826fail:
827 return NULL;
828}
829
830struct sctp_ulpevent *sctp_ulpevent_make_authkey(
831 const struct sctp_association *asoc, __u16 key_id,
832 __u32 indication, gfp_t gfp)
833{
834 struct sctp_ulpevent *event;
835 struct sctp_authkey_event *ak;
836 struct sk_buff *skb;
837
838 event = sctp_ulpevent_new(sizeof(struct sctp_authkey_event),
839 MSG_NOTIFICATION, gfp);
840 if (!event)
841 goto fail;
842
843 skb = sctp_event2skb(event);
844 ak = (struct sctp_authkey_event *)
845 skb_put(skb, sizeof(struct sctp_authkey_event));
846
847 ak->auth_type = SCTP_AUTHENTICATION_EVENT;
848 ak->auth_flags = 0;
849 ak->auth_length = sizeof(struct sctp_authkey_event);
850
851 ak->auth_keynumber = key_id;
852 ak->auth_altkeynumber = 0;
853 ak->auth_indication = indication;
854
855 /*
856 * The association id field, holds the identifier for the association.
857 */
858 sctp_ulpevent_set_owner(event, asoc);
859 ak->auth_assoc_id = sctp_assoc2id(asoc);
860
861 return event;
862fail:
863 return NULL;
864}
865
866/*
867 * Socket Extensions for SCTP
868 * 6.3.10. SCTP_SENDER_DRY_EVENT
869 */
870struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event(
871 const struct sctp_association *asoc, gfp_t gfp)
872{
873 struct sctp_ulpevent *event;
874 struct sctp_sender_dry_event *sdry;
875 struct sk_buff *skb;
876
877 event = sctp_ulpevent_new(sizeof(struct sctp_sender_dry_event),
878 MSG_NOTIFICATION, gfp);
879 if (!event)
880 return NULL;
881
882 skb = sctp_event2skb(event);
883 sdry = (struct sctp_sender_dry_event *)
884 skb_put(skb, sizeof(struct sctp_sender_dry_event));
885
886 sdry->sender_dry_type = SCTP_SENDER_DRY_EVENT;
887 sdry->sender_dry_flags = 0;
888 sdry->sender_dry_length = sizeof(struct sctp_sender_dry_event);
889 sctp_ulpevent_set_owner(event, asoc);
890 sdry->sender_dry_assoc_id = sctp_assoc2id(asoc);
891
892 return event;
893}
894
895/* Return the notification type, assuming this is a notification
896 * event.
897 */
898__u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event)
899{
900 union sctp_notification *notification;
901 struct sk_buff *skb;
902
903 skb = sctp_event2skb(event);
904 notification = (union sctp_notification *) skb->data;
905 return notification->sn_header.sn_type;
906}
907
908/* Copy out the sndrcvinfo into a msghdr. */
909void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
910 struct msghdr *msghdr)
911{
912 struct sctp_sndrcvinfo sinfo;
913
914 if (sctp_ulpevent_is_notification(event))
915 return;
916
917 /* Sockets API Extensions for SCTP
918 * Section 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
919 *
920 * sinfo_stream: 16 bits (unsigned integer)
921 *
922 * For recvmsg() the SCTP stack places the message's stream number in
923 * this value.
924 */
925 sinfo.sinfo_stream = event->stream;
926 /* sinfo_ssn: 16 bits (unsigned integer)
927 *
928 * For recvmsg() this value contains the stream sequence number that
929 * the remote endpoint placed in the DATA chunk. For fragmented
930 * messages this is the same number for all deliveries of the message
931 * (if more than one recvmsg() is needed to read the message).
932 */
933 sinfo.sinfo_ssn = event->ssn;
934 /* sinfo_ppid: 32 bits (unsigned integer)
935 *
936 * In recvmsg() this value is
937 * the same information that was passed by the upper layer in the peer
938 * application. Please note that byte order issues are NOT accounted
939 * for and this information is passed opaquely by the SCTP stack from
940 * one end to the other.
941 */
942 sinfo.sinfo_ppid = event->ppid;
943 /* sinfo_flags: 16 bits (unsigned integer)
944 *
945 * This field may contain any of the following flags and is composed of
946 * a bitwise OR of these values.
947 *
948 * recvmsg() flags:
949 *
950 * SCTP_UNORDERED - This flag is present when the message was sent
951 * non-ordered.
952 */
953 sinfo.sinfo_flags = event->flags;
954 /* sinfo_tsn: 32 bit (unsigned integer)
955 *
956 * For the receiving side, this field holds a TSN that was
957 * assigned to one of the SCTP Data Chunks.
958 */
959 sinfo.sinfo_tsn = event->tsn;
960 /* sinfo_cumtsn: 32 bit (unsigned integer)
961 *
962 * This field will hold the current cumulative TSN as
963 * known by the underlying SCTP layer. Note this field is
964 * ignored when sending and only valid for a receive
965 * operation when sinfo_flags are set to SCTP_UNORDERED.
966 */
967 sinfo.sinfo_cumtsn = event->cumtsn;
968 /* sinfo_assoc_id: sizeof (sctp_assoc_t)
969 *
970 * The association handle field, sinfo_assoc_id, holds the identifier
971 * for the association announced in the COMMUNICATION_UP notification.
972 * All notifications for a given association have the same identifier.
973 * Ignored for one-to-one style sockets.
974 */
975 sinfo.sinfo_assoc_id = sctp_assoc2id(event->asoc);
976
977 /* context value that is set via SCTP_CONTEXT socket option. */
978 sinfo.sinfo_context = event->asoc->default_rcv_context;
979
980 /* These fields are not used while receiving. */
981 sinfo.sinfo_timetolive = 0;
982
983 put_cmsg(msghdr, IPPROTO_SCTP, SCTP_SNDRCV,
984 sizeof(struct sctp_sndrcvinfo), (void *)&sinfo);
985}
986
987/* Do accounting for bytes received and hold a reference to the association
988 * for each skb.
989 */
990static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
991 struct sctp_association *asoc)
992{
993 struct sk_buff *skb, *frag;
994
995 skb = sctp_event2skb(event);
996 /* Set the owner and charge rwnd for bytes received. */
997 sctp_ulpevent_set_owner(event, asoc);
998 sctp_assoc_rwnd_decrease(asoc, skb_headlen(skb));
999
1000 if (!skb->data_len)
1001 return;
1002
1003 /* Note: Not clearing the entire event struct as this is just a
1004 * fragment of the real event. However, we still need to do rwnd
1005 * accounting.
1006 * In general, the skb passed from IP can have only 1 level of
1007 * fragments. But we allow multiple levels of fragments.
1008 */
1009 skb_walk_frags(skb, frag)
1010 sctp_ulpevent_receive_data(sctp_skb2event(frag), asoc);
1011}
1012
1013/* Do accounting for bytes just read by user and release the references to
1014 * the association.
1015 */
1016static void sctp_ulpevent_release_data(struct sctp_ulpevent *event)
1017{
1018 struct sk_buff *skb, *frag;
1019 unsigned int len;
1020
1021 /* Current stack structures assume that the rcv buffer is
1022 * per socket. For UDP style sockets this is not true as
1023 * multiple associations may be on a single UDP-style socket.
1024 * Use the local private area of the skb to track the owning
1025 * association.
1026 */
1027
1028 skb = sctp_event2skb(event);
1029 len = skb->len;
1030
1031 if (!skb->data_len)
1032 goto done;
1033
1034 /* Don't forget the fragments. */
1035 skb_walk_frags(skb, frag) {
1036 /* NOTE: skb_shinfos are recursive. Although IP returns
1037 * skb's with only 1 level of fragments, SCTP reassembly can
1038 * increase the levels.
1039 */
1040 sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
1041 }
1042
1043done:
1044 sctp_assoc_rwnd_increase(event->asoc, len);
1045 sctp_ulpevent_release_owner(event);
1046}
1047
1048static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event)
1049{
1050 struct sk_buff *skb, *frag;
1051
1052 skb = sctp_event2skb(event);
1053
1054 if (!skb->data_len)
1055 goto done;
1056
1057 /* Don't forget the fragments. */
1058 skb_walk_frags(skb, frag) {
1059 /* NOTE: skb_shinfos are recursive. Although IP returns
1060 * skb's with only 1 level of fragments, SCTP reassembly can
1061 * increase the levels.
1062 */
1063 sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
1064 }
1065
1066done:
1067 sctp_ulpevent_release_owner(event);
1068}
1069
1070/* Free a ulpevent that has an owner. It includes releasing the reference
1071 * to the owner, updating the rwnd in case of a DATA event and freeing the
1072 * skb.
1073 */
1074void sctp_ulpevent_free(struct sctp_ulpevent *event)
1075{
1076 if (sctp_ulpevent_is_notification(event))
1077 sctp_ulpevent_release_owner(event);
1078 else
1079 sctp_ulpevent_release_data(event);
1080
1081 kfree_skb(sctp_event2skb(event));
1082}
1083
1084/* Purge the skb lists holding ulpevents. */
1085unsigned int sctp_queue_purge_ulpevents(struct sk_buff_head *list)
1086{
1087 struct sk_buff *skb;
1088 unsigned int data_unread = 0;
1089
1090 while ((skb = skb_dequeue(list)) != NULL) {
1091 struct sctp_ulpevent *event = sctp_skb2event(skb);
1092
1093 if (!sctp_ulpevent_is_notification(event))
1094 data_unread += skb->len;
1095
1096 sctp_ulpevent_free(event);
1097 }
1098
1099 return data_unread;
1100}