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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, 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}
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_to_user(
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 *
370sctp_ulpevent_make_remote_error(const struct sctp_association *asoc,
371 struct sctp_chunk *chunk, __u16 flags,
372 gfp_t gfp)
373{
374 struct sctp_ulpevent *event;
375 struct sctp_remote_error *sre;
376 struct sk_buff *skb;
377 sctp_errhdr_t *ch;
378 __be16 cause;
379 int elen;
380
381 ch = (sctp_errhdr_t *)(chunk->skb->data);
382 cause = ch->cause;
383 elen = WORD_ROUND(ntohs(ch->length)) - sizeof(sctp_errhdr_t);
384
385 /* Pull off the ERROR header. */
386 skb_pull(chunk->skb, sizeof(sctp_errhdr_t));
387
388 /* Copy the skb to a new skb with room for us to prepend
389 * notification with.
390 */
391 skb = skb_copy_expand(chunk->skb, sizeof(*sre), 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 *) skb_push(skb, sizeof(*sre));
403
404 /* Trim the buffer to the right length. */
405 skb_trim(skb, sizeof(*sre) + elen);
406
407 /* RFC6458, Section 6.1.3. SCTP_REMOTE_ERROR */
408 memset(sre, 0, sizeof(*sre));
409 sre->sre_type = SCTP_REMOTE_ERROR;
410 sre->sre_flags = 0;
411 sre->sre_length = skb->len;
412 sre->sre_error = cause;
413 sctp_ulpevent_set_owner(event, asoc);
414 sre->sre_assoc_id = sctp_assoc2id(asoc);
415
416 return event;
417fail:
418 return NULL;
419}
420
421/* Create and initialize a SCTP_SEND_FAILED notification.
422 *
423 * Socket Extensions for SCTP - draft-01
424 * 5.3.1.4 SCTP_SEND_FAILED
425 */
426struct sctp_ulpevent *sctp_ulpevent_make_send_failed(
427 const struct sctp_association *asoc, struct sctp_chunk *chunk,
428 __u16 flags, __u32 error, gfp_t gfp)
429{
430 struct sctp_ulpevent *event;
431 struct sctp_send_failed *ssf;
432 struct sk_buff *skb;
433
434 /* Pull off any padding. */
435 int len = ntohs(chunk->chunk_hdr->length);
436
437 /* Make skb with more room so we can prepend notification. */
438 skb = skb_copy_expand(chunk->skb,
439 sizeof(struct sctp_send_failed), /* headroom */
440 0, /* tailroom */
441 gfp);
442 if (!skb)
443 goto fail;
444
445 /* Pull off the common chunk header and DATA header. */
446 skb_pull(skb, sizeof(struct sctp_data_chunk));
447 len -= sizeof(struct sctp_data_chunk);
448
449 /* Embed the event fields inside the cloned skb. */
450 event = sctp_skb2event(skb);
451 sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
452
453 ssf = (struct sctp_send_failed *)
454 skb_push(skb, sizeof(struct sctp_send_failed));
455
456 /* Socket Extensions for SCTP
457 * 5.3.1.4 SCTP_SEND_FAILED
458 *
459 * ssf_type:
460 * It should be SCTP_SEND_FAILED.
461 */
462 ssf->ssf_type = SCTP_SEND_FAILED;
463
464 /* Socket Extensions for SCTP
465 * 5.3.1.4 SCTP_SEND_FAILED
466 *
467 * ssf_flags: 16 bits (unsigned integer)
468 * The flag value will take one of the following values
469 *
470 * SCTP_DATA_UNSENT - Indicates that the data was never put on
471 * the wire.
472 *
473 * SCTP_DATA_SENT - Indicates that the data was put on the wire.
474 * Note that this does not necessarily mean that the
475 * data was (or was not) successfully delivered.
476 */
477 ssf->ssf_flags = flags;
478
479 /* Socket Extensions for SCTP
480 * 5.3.1.4 SCTP_SEND_FAILED
481 *
482 * ssf_length: sizeof (__u32)
483 * This field is the total length of the notification data, including
484 * the notification header.
485 */
486 ssf->ssf_length = sizeof(struct sctp_send_failed) + len;
487 skb_trim(skb, ssf->ssf_length);
488
489 /* Socket Extensions for SCTP
490 * 5.3.1.4 SCTP_SEND_FAILED
491 *
492 * ssf_error: 16 bits (unsigned integer)
493 * This value represents the reason why the send failed, and if set,
494 * will be a SCTP protocol error code as defined in [SCTP] section
495 * 3.3.10.
496 */
497 ssf->ssf_error = error;
498
499 /* Socket Extensions for SCTP
500 * 5.3.1.4 SCTP_SEND_FAILED
501 *
502 * ssf_info: sizeof (struct sctp_sndrcvinfo)
503 * The original send information associated with the undelivered
504 * message.
505 */
506 memcpy(&ssf->ssf_info, &chunk->sinfo, sizeof(struct sctp_sndrcvinfo));
507
508 /* Per TSVWG discussion with Randy. Allow the application to
509 * reassemble a fragmented message.
510 */
511 ssf->ssf_info.sinfo_flags = chunk->chunk_hdr->flags;
512
513 /* Socket Extensions for SCTP
514 * 5.3.1.4 SCTP_SEND_FAILED
515 *
516 * ssf_assoc_id: sizeof (sctp_assoc_t)
517 * The association id field, sf_assoc_id, holds the identifier for the
518 * association. All notifications for a given association have the
519 * same association identifier. For TCP style socket, this field is
520 * ignored.
521 */
522 sctp_ulpevent_set_owner(event, asoc);
523 ssf->ssf_assoc_id = sctp_assoc2id(asoc);
524 return event;
525
526fail:
527 return NULL;
528}
529
530/* Create and initialize a SCTP_SHUTDOWN_EVENT notification.
531 *
532 * Socket Extensions for SCTP - draft-01
533 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
534 */
535struct sctp_ulpevent *sctp_ulpevent_make_shutdown_event(
536 const struct sctp_association *asoc,
537 __u16 flags, gfp_t gfp)
538{
539 struct sctp_ulpevent *event;
540 struct sctp_shutdown_event *sse;
541 struct sk_buff *skb;
542
543 event = sctp_ulpevent_new(sizeof(struct sctp_shutdown_event),
544 MSG_NOTIFICATION, gfp);
545 if (!event)
546 goto fail;
547
548 skb = sctp_event2skb(event);
549 sse = (struct sctp_shutdown_event *)
550 skb_put(skb, sizeof(struct sctp_shutdown_event));
551
552 /* Socket Extensions for SCTP
553 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
554 *
555 * sse_type
556 * It should be SCTP_SHUTDOWN_EVENT
557 */
558 sse->sse_type = SCTP_SHUTDOWN_EVENT;
559
560 /* Socket Extensions for SCTP
561 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
562 *
563 * sse_flags: 16 bits (unsigned integer)
564 * Currently unused.
565 */
566 sse->sse_flags = 0;
567
568 /* Socket Extensions for SCTP
569 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
570 *
571 * sse_length: sizeof (__u32)
572 * This field is the total length of the notification data, including
573 * the notification header.
574 */
575 sse->sse_length = sizeof(struct sctp_shutdown_event);
576
577 /* Socket Extensions for SCTP
578 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
579 *
580 * sse_assoc_id: sizeof (sctp_assoc_t)
581 * The association id field, holds the identifier for the association.
582 * All notifications for a given association have the same association
583 * identifier. For TCP style socket, this field is ignored.
584 */
585 sctp_ulpevent_set_owner(event, asoc);
586 sse->sse_assoc_id = sctp_assoc2id(asoc);
587
588 return event;
589
590fail:
591 return NULL;
592}
593
594/* Create and initialize a SCTP_ADAPTATION_INDICATION notification.
595 *
596 * Socket Extensions for SCTP
597 * 5.3.1.6 SCTP_ADAPTATION_INDICATION
598 */
599struct sctp_ulpevent *sctp_ulpevent_make_adaptation_indication(
600 const struct sctp_association *asoc, gfp_t gfp)
601{
602 struct sctp_ulpevent *event;
603 struct sctp_adaptation_event *sai;
604 struct sk_buff *skb;
605
606 event = sctp_ulpevent_new(sizeof(struct sctp_adaptation_event),
607 MSG_NOTIFICATION, gfp);
608 if (!event)
609 goto fail;
610
611 skb = sctp_event2skb(event);
612 sai = (struct sctp_adaptation_event *)
613 skb_put(skb, sizeof(struct sctp_adaptation_event));
614
615 sai->sai_type = SCTP_ADAPTATION_INDICATION;
616 sai->sai_flags = 0;
617 sai->sai_length = sizeof(struct sctp_adaptation_event);
618 sai->sai_adaptation_ind = asoc->peer.adaptation_ind;
619 sctp_ulpevent_set_owner(event, asoc);
620 sai->sai_assoc_id = sctp_assoc2id(asoc);
621
622 return event;
623
624fail:
625 return NULL;
626}
627
628/* A message has been received. Package this message as a notification
629 * to pass it to the upper layers. Go ahead and calculate the sndrcvinfo
630 * even if filtered out later.
631 *
632 * Socket Extensions for SCTP
633 * 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
634 */
635struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc,
636 struct sctp_chunk *chunk,
637 gfp_t gfp)
638{
639 struct sctp_ulpevent *event = NULL;
640 struct sk_buff *skb;
641 size_t padding, len;
642 int rx_count;
643
644 /*
645 * check to see if we need to make space for this
646 * new skb, expand the rcvbuffer if needed, or drop
647 * the frame
648 */
649 if (asoc->ep->rcvbuf_policy)
650 rx_count = atomic_read(&asoc->rmem_alloc);
651 else
652 rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
653
654 if (rx_count >= asoc->base.sk->sk_rcvbuf) {
655
656 if ((asoc->base.sk->sk_userlocks & SOCK_RCVBUF_LOCK) ||
657 (!sk_rmem_schedule(asoc->base.sk, chunk->skb,
658 chunk->skb->truesize)))
659 goto fail;
660 }
661
662 /* Clone the original skb, sharing the data. */
663 skb = skb_clone(chunk->skb, gfp);
664 if (!skb)
665 goto fail;
666
667 /* Now that all memory allocations for this chunk succeeded, we
668 * can mark it as received so the tsn_map is updated correctly.
669 */
670 if (sctp_tsnmap_mark(&asoc->peer.tsn_map,
671 ntohl(chunk->subh.data_hdr->tsn),
672 chunk->transport))
673 goto fail_mark;
674
675 /* First calculate the padding, so we don't inadvertently
676 * pass up the wrong length to the user.
677 *
678 * RFC 2960 - Section 3.2 Chunk Field Descriptions
679 *
680 * The total length of a chunk(including Type, Length and Value fields)
681 * MUST be a multiple of 4 bytes. If the length of the chunk is not a
682 * multiple of 4 bytes, the sender MUST pad the chunk with all zero
683 * bytes and this padding is not included in the chunk length field.
684 * The sender should never pad with more than 3 bytes. The receiver
685 * MUST ignore the padding bytes.
686 */
687 len = ntohs(chunk->chunk_hdr->length);
688 padding = WORD_ROUND(len) - len;
689
690 /* Fixup cloned skb with just this chunks data. */
691 skb_trim(skb, chunk->chunk_end - padding - skb->data);
692
693 /* Embed the event fields inside the cloned skb. */
694 event = sctp_skb2event(skb);
695
696 /* Initialize event with flags 0 and correct length
697 * Since this is a clone of the original skb, only account for
698 * the data of this chunk as other chunks will be accounted separately.
699 */
700 sctp_ulpevent_init(event, 0, skb->len + sizeof(struct sk_buff));
701
702 sctp_ulpevent_receive_data(event, asoc);
703
704 event->stream = ntohs(chunk->subh.data_hdr->stream);
705 event->ssn = ntohs(chunk->subh.data_hdr->ssn);
706 event->ppid = chunk->subh.data_hdr->ppid;
707 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
708 event->flags |= SCTP_UNORDERED;
709 event->cumtsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
710 }
711 event->tsn = ntohl(chunk->subh.data_hdr->tsn);
712 event->msg_flags |= chunk->chunk_hdr->flags;
713 event->iif = sctp_chunk_iif(chunk);
714
715 return event;
716
717fail_mark:
718 kfree_skb(skb);
719fail:
720 return NULL;
721}
722
723/* Create a partial delivery related event.
724 *
725 * 5.3.1.7 SCTP_PARTIAL_DELIVERY_EVENT
726 *
727 * When a receiver is engaged in a partial delivery of a
728 * message this notification will be used to indicate
729 * various events.
730 */
731struct sctp_ulpevent *sctp_ulpevent_make_pdapi(
732 const struct sctp_association *asoc, __u32 indication,
733 gfp_t gfp)
734{
735 struct sctp_ulpevent *event;
736 struct sctp_pdapi_event *pd;
737 struct sk_buff *skb;
738
739 event = sctp_ulpevent_new(sizeof(struct sctp_pdapi_event),
740 MSG_NOTIFICATION, gfp);
741 if (!event)
742 goto fail;
743
744 skb = sctp_event2skb(event);
745 pd = (struct sctp_pdapi_event *)
746 skb_put(skb, sizeof(struct sctp_pdapi_event));
747
748 /* pdapi_type
749 * It should be SCTP_PARTIAL_DELIVERY_EVENT
750 *
751 * pdapi_flags: 16 bits (unsigned integer)
752 * Currently unused.
753 */
754 pd->pdapi_type = SCTP_PARTIAL_DELIVERY_EVENT;
755 pd->pdapi_flags = 0;
756
757 /* pdapi_length: 32 bits (unsigned integer)
758 *
759 * This field is the total length of the notification data, including
760 * the notification header. It will generally be sizeof (struct
761 * sctp_pdapi_event).
762 */
763 pd->pdapi_length = sizeof(struct sctp_pdapi_event);
764
765 /* pdapi_indication: 32 bits (unsigned integer)
766 *
767 * This field holds the indication being sent to the application.
768 */
769 pd->pdapi_indication = indication;
770
771 /* pdapi_assoc_id: sizeof (sctp_assoc_t)
772 *
773 * The association id field, holds the identifier for the association.
774 */
775 sctp_ulpevent_set_owner(event, asoc);
776 pd->pdapi_assoc_id = sctp_assoc2id(asoc);
777
778 return event;
779fail:
780 return NULL;
781}
782
783struct sctp_ulpevent *sctp_ulpevent_make_authkey(
784 const struct sctp_association *asoc, __u16 key_id,
785 __u32 indication, gfp_t gfp)
786{
787 struct sctp_ulpevent *event;
788 struct sctp_authkey_event *ak;
789 struct sk_buff *skb;
790
791 event = sctp_ulpevent_new(sizeof(struct sctp_authkey_event),
792 MSG_NOTIFICATION, gfp);
793 if (!event)
794 goto fail;
795
796 skb = sctp_event2skb(event);
797 ak = (struct sctp_authkey_event *)
798 skb_put(skb, sizeof(struct sctp_authkey_event));
799
800 ak->auth_type = SCTP_AUTHENTICATION_EVENT;
801 ak->auth_flags = 0;
802 ak->auth_length = sizeof(struct sctp_authkey_event);
803
804 ak->auth_keynumber = key_id;
805 ak->auth_altkeynumber = 0;
806 ak->auth_indication = indication;
807
808 /*
809 * The association id field, holds the identifier for the association.
810 */
811 sctp_ulpevent_set_owner(event, asoc);
812 ak->auth_assoc_id = sctp_assoc2id(asoc);
813
814 return event;
815fail:
816 return NULL;
817}
818
819/*
820 * Socket Extensions for SCTP
821 * 6.3.10. SCTP_SENDER_DRY_EVENT
822 */
823struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event(
824 const struct sctp_association *asoc, gfp_t gfp)
825{
826 struct sctp_ulpevent *event;
827 struct sctp_sender_dry_event *sdry;
828 struct sk_buff *skb;
829
830 event = sctp_ulpevent_new(sizeof(struct sctp_sender_dry_event),
831 MSG_NOTIFICATION, gfp);
832 if (!event)
833 return NULL;
834
835 skb = sctp_event2skb(event);
836 sdry = (struct sctp_sender_dry_event *)
837 skb_put(skb, sizeof(struct sctp_sender_dry_event));
838
839 sdry->sender_dry_type = SCTP_SENDER_DRY_EVENT;
840 sdry->sender_dry_flags = 0;
841 sdry->sender_dry_length = sizeof(struct sctp_sender_dry_event);
842 sctp_ulpevent_set_owner(event, asoc);
843 sdry->sender_dry_assoc_id = sctp_assoc2id(asoc);
844
845 return event;
846}
847
848/* Return the notification type, assuming this is a notification
849 * event.
850 */
851__u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event)
852{
853 union sctp_notification *notification;
854 struct sk_buff *skb;
855
856 skb = sctp_event2skb(event);
857 notification = (union sctp_notification *) skb->data;
858 return notification->sn_header.sn_type;
859}
860
861/* RFC6458, Section 5.3.2. SCTP Header Information Structure
862 * (SCTP_SNDRCV, DEPRECATED)
863 */
864void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
865 struct msghdr *msghdr)
866{
867 struct sctp_sndrcvinfo sinfo;
868
869 if (sctp_ulpevent_is_notification(event))
870 return;
871
872 memset(&sinfo, 0, sizeof(sinfo));
873 sinfo.sinfo_stream = event->stream;
874 sinfo.sinfo_ssn = event->ssn;
875 sinfo.sinfo_ppid = event->ppid;
876 sinfo.sinfo_flags = event->flags;
877 sinfo.sinfo_tsn = event->tsn;
878 sinfo.sinfo_cumtsn = event->cumtsn;
879 sinfo.sinfo_assoc_id = sctp_assoc2id(event->asoc);
880 /* Context value that is set via SCTP_CONTEXT socket option. */
881 sinfo.sinfo_context = event->asoc->default_rcv_context;
882 /* These fields are not used while receiving. */
883 sinfo.sinfo_timetolive = 0;
884
885 put_cmsg(msghdr, IPPROTO_SCTP, SCTP_SNDRCV,
886 sizeof(sinfo), &sinfo);
887}
888
889/* RFC6458, Section 5.3.5 SCTP Receive Information Structure
890 * (SCTP_SNDRCV)
891 */
892void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event,
893 struct msghdr *msghdr)
894{
895 struct sctp_rcvinfo rinfo;
896
897 if (sctp_ulpevent_is_notification(event))
898 return;
899
900 memset(&rinfo, 0, sizeof(struct sctp_rcvinfo));
901 rinfo.rcv_sid = event->stream;
902 rinfo.rcv_ssn = event->ssn;
903 rinfo.rcv_ppid = event->ppid;
904 rinfo.rcv_flags = event->flags;
905 rinfo.rcv_tsn = event->tsn;
906 rinfo.rcv_cumtsn = event->cumtsn;
907 rinfo.rcv_assoc_id = sctp_assoc2id(event->asoc);
908 rinfo.rcv_context = event->asoc->default_rcv_context;
909
910 put_cmsg(msghdr, IPPROTO_SCTP, SCTP_RCVINFO,
911 sizeof(rinfo), &rinfo);
912}
913
914/* RFC6458, Section 5.3.6. SCTP Next Receive Information Structure
915 * (SCTP_NXTINFO)
916 */
917static void __sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
918 struct msghdr *msghdr,
919 const struct sk_buff *skb)
920{
921 struct sctp_nxtinfo nxtinfo;
922
923 memset(&nxtinfo, 0, sizeof(nxtinfo));
924 nxtinfo.nxt_sid = event->stream;
925 nxtinfo.nxt_ppid = event->ppid;
926 nxtinfo.nxt_flags = event->flags;
927 if (sctp_ulpevent_is_notification(event))
928 nxtinfo.nxt_flags |= SCTP_NOTIFICATION;
929 nxtinfo.nxt_length = skb->len;
930 nxtinfo.nxt_assoc_id = sctp_assoc2id(event->asoc);
931
932 put_cmsg(msghdr, IPPROTO_SCTP, SCTP_NXTINFO,
933 sizeof(nxtinfo), &nxtinfo);
934}
935
936void sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
937 struct msghdr *msghdr,
938 struct sock *sk)
939{
940 struct sk_buff *skb;
941 int err;
942
943 skb = sctp_skb_recv_datagram(sk, MSG_PEEK, 1, &err);
944 if (skb != NULL) {
945 __sctp_ulpevent_read_nxtinfo(sctp_skb2event(skb),
946 msghdr, skb);
947 /* Just release refcount here. */
948 kfree_skb(skb);
949 }
950}
951
952/* Do accounting for bytes received and hold a reference to the association
953 * for each skb.
954 */
955static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
956 struct sctp_association *asoc)
957{
958 struct sk_buff *skb, *frag;
959
960 skb = sctp_event2skb(event);
961 /* Set the owner and charge rwnd for bytes received. */
962 sctp_ulpevent_set_owner(event, asoc);
963 sctp_assoc_rwnd_decrease(asoc, skb_headlen(skb));
964
965 if (!skb->data_len)
966 return;
967
968 /* Note: Not clearing the entire event struct as this is just a
969 * fragment of the real event. However, we still need to do rwnd
970 * accounting.
971 * In general, the skb passed from IP can have only 1 level of
972 * fragments. But we allow multiple levels of fragments.
973 */
974 skb_walk_frags(skb, frag)
975 sctp_ulpevent_receive_data(sctp_skb2event(frag), asoc);
976}
977
978/* Do accounting for bytes just read by user and release the references to
979 * the association.
980 */
981static void sctp_ulpevent_release_data(struct sctp_ulpevent *event)
982{
983 struct sk_buff *skb, *frag;
984 unsigned int len;
985
986 /* Current stack structures assume that the rcv buffer is
987 * per socket. For UDP style sockets this is not true as
988 * multiple associations may be on a single UDP-style socket.
989 * Use the local private area of the skb to track the owning
990 * association.
991 */
992
993 skb = sctp_event2skb(event);
994 len = skb->len;
995
996 if (!skb->data_len)
997 goto done;
998
999 /* Don't forget the fragments. */
1000 skb_walk_frags(skb, frag) {
1001 /* NOTE: skb_shinfos are recursive. Although IP returns
1002 * skb's with only 1 level of fragments, SCTP reassembly can
1003 * increase the levels.
1004 */
1005 sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
1006 }
1007
1008done:
1009 sctp_assoc_rwnd_increase(event->asoc, len);
1010 sctp_ulpevent_release_owner(event);
1011}
1012
1013static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event)
1014{
1015 struct sk_buff *skb, *frag;
1016
1017 skb = sctp_event2skb(event);
1018
1019 if (!skb->data_len)
1020 goto done;
1021
1022 /* Don't forget the fragments. */
1023 skb_walk_frags(skb, frag) {
1024 /* NOTE: skb_shinfos are recursive. Although IP returns
1025 * skb's with only 1 level of fragments, SCTP reassembly can
1026 * increase the levels.
1027 */
1028 sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
1029 }
1030
1031done:
1032 sctp_ulpevent_release_owner(event);
1033}
1034
1035/* Free a ulpevent that has an owner. It includes releasing the reference
1036 * to the owner, updating the rwnd in case of a DATA event and freeing the
1037 * skb.
1038 */
1039void sctp_ulpevent_free(struct sctp_ulpevent *event)
1040{
1041 if (sctp_ulpevent_is_notification(event))
1042 sctp_ulpevent_release_owner(event);
1043 else
1044 sctp_ulpevent_release_data(event);
1045
1046 kfree_skb(sctp_event2skb(event));
1047}
1048
1049/* Purge the skb lists holding ulpevents. */
1050unsigned int sctp_queue_purge_ulpevents(struct sk_buff_head *list)
1051{
1052 struct sk_buff *skb;
1053 unsigned int data_unread = 0;
1054
1055 while ((skb = skb_dequeue(list)) != NULL) {
1056 struct sctp_ulpevent *event = sctp_skb2event(skb);
1057
1058 if (!sctp_ulpevent_is_notification(event))
1059 data_unread += skb->len;
1060
1061 sctp_ulpevent_free(event);
1062 }
1063
1064 return data_unread;
1065}