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