ia64/linux-2.6.18-xen.hg

view net/sctp/ulpevent.c @ 871:9cbcc9008446

xen/x86: don't initialize cpu_data[]'s apicid field on generic code

Afaict, this is not only redundant with the intialization done in
drivers/xen/core/smpboot.c, but actually results - at least for
secondary CPUs - in the Xen-specific value written to be later
overwritten with whatever the generic code determines (with no
guarantee that the two values are identical).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu May 14 10:09:15 2009 +0100 (2009-05-14)
parents 831230e53067
children
line source
1 /* SCTP kernel reference 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 * The SCTP reference implementation is free software;
12 * you can redistribute it and/or modify it under the terms of
13 * the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
15 * any later version.
16 *
17 * The SCTP reference implementation is distributed in the hope that it
18 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19 * ************************
20 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21 * See the GNU General Public License for more details.
22 *
23 * You should have received a copy of the GNU General Public License
24 * along with GNU CC; see the file COPYING. If not, write to
25 * the Free Software Foundation, 59 Temple Place - Suite 330,
26 * Boston, MA 02111-1307, USA.
27 *
28 * Please send any bug reports or fixes you make to the
29 * email address(es):
30 * lksctp developers <lksctp-developers@lists.sourceforge.net>
31 *
32 * Or submit a bug report through the following website:
33 * http://www.sf.net/projects/lksctp
34 *
35 * Written or modified by:
36 * Jon Grimm <jgrimm@us.ibm.com>
37 * La Monte H.P. Yarroll <piggy@acm.org>
38 * Ardelle Fan <ardelle.fan@intel.com>
39 * Sridhar Samudrala <sri@us.ibm.com>
40 *
41 * Any bugs reported given to us we will try to fix... any fixes shared will
42 * be incorporated into the next SCTP release.
43 */
45 #include <linux/types.h>
46 #include <linux/skbuff.h>
47 #include <net/sctp/structs.h>
48 #include <net/sctp/sctp.h>
49 #include <net/sctp/sm.h>
51 static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
52 struct sctp_association *asoc);
53 static void sctp_ulpevent_release_data(struct sctp_ulpevent *event);
54 static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event);
57 /* Initialize an ULP event from an given skb. */
58 SCTP_STATIC void sctp_ulpevent_init(struct sctp_ulpevent *event, int msg_flags)
59 {
60 memset(event, 0, sizeof(struct sctp_ulpevent));
61 event->msg_flags = msg_flags;
62 }
64 /* Create a new sctp_ulpevent. */
65 SCTP_STATIC struct sctp_ulpevent *sctp_ulpevent_new(int size, int msg_flags,
66 gfp_t gfp)
67 {
68 struct sctp_ulpevent *event;
69 struct sk_buff *skb;
71 skb = alloc_skb(size, gfp);
72 if (!skb)
73 goto fail;
75 event = sctp_skb2event(skb);
76 sctp_ulpevent_init(event, msg_flags);
78 return event;
80 fail:
81 return NULL;
82 }
84 /* Is this a MSG_NOTIFICATION? */
85 int sctp_ulpevent_is_notification(const struct sctp_ulpevent *event)
86 {
87 return MSG_NOTIFICATION == (event->msg_flags & MSG_NOTIFICATION);
88 }
90 /* Hold the association in case the msg_name needs read out of
91 * the association.
92 */
93 static inline void sctp_ulpevent_set_owner(struct sctp_ulpevent *event,
94 const struct sctp_association *asoc)
95 {
96 struct sk_buff *skb;
98 /* Cast away the const, as we are just wanting to
99 * bump the reference count.
100 */
101 sctp_association_hold((struct sctp_association *)asoc);
102 skb = sctp_event2skb(event);
103 event->asoc = (struct sctp_association *)asoc;
104 atomic_add(skb->truesize, &event->asoc->rmem_alloc);
105 skb_set_owner_r(skb, asoc->base.sk);
106 }
108 /* A simple destructor to give up the reference to the association. */
109 static inline void sctp_ulpevent_release_owner(struct sctp_ulpevent *event)
110 {
111 struct sctp_association *asoc = event->asoc;
112 struct sk_buff *skb = sctp_event2skb(event);
114 atomic_sub(skb->truesize, &asoc->rmem_alloc);
115 sctp_association_put(asoc);
116 }
118 /* Create and initialize an SCTP_ASSOC_CHANGE event.
119 *
120 * 5.3.1.1 SCTP_ASSOC_CHANGE
121 *
122 * Communication notifications inform the ULP that an SCTP association
123 * has either begun or ended. The identifier for a new association is
124 * provided by this notification.
125 *
126 * Note: There is no field checking here. If a field is unused it will be
127 * zero'd out.
128 */
129 struct sctp_ulpevent *sctp_ulpevent_make_assoc_change(
130 const struct sctp_association *asoc,
131 __u16 flags, __u16 state, __u16 error, __u16 outbound,
132 __u16 inbound, gfp_t gfp)
133 {
134 struct sctp_ulpevent *event;
135 struct sctp_assoc_change *sac;
136 struct sk_buff *skb;
138 event = sctp_ulpevent_new(sizeof(struct sctp_assoc_change),
139 MSG_NOTIFICATION, gfp);
140 if (!event)
141 goto fail;
142 skb = sctp_event2skb(event);
143 sac = (struct sctp_assoc_change *)
144 skb_put(skb, sizeof(struct sctp_assoc_change));
146 /* Socket Extensions for SCTP
147 * 5.3.1.1 SCTP_ASSOC_CHANGE
148 *
149 * sac_type:
150 * It should be SCTP_ASSOC_CHANGE.
151 */
152 sac->sac_type = SCTP_ASSOC_CHANGE;
154 /* Socket Extensions for SCTP
155 * 5.3.1.1 SCTP_ASSOC_CHANGE
156 *
157 * sac_state: 32 bits (signed integer)
158 * This field holds one of a number of values that communicate the
159 * event that happened to the association.
160 */
161 sac->sac_state = state;
163 /* Socket Extensions for SCTP
164 * 5.3.1.1 SCTP_ASSOC_CHANGE
165 *
166 * sac_flags: 16 bits (unsigned integer)
167 * Currently unused.
168 */
169 sac->sac_flags = 0;
171 /* Socket Extensions for SCTP
172 * 5.3.1.1 SCTP_ASSOC_CHANGE
173 *
174 * sac_length: sizeof (__u32)
175 * This field is the total length of the notification data, including
176 * the notification header.
177 */
178 sac->sac_length = sizeof(struct sctp_assoc_change);
180 /* Socket Extensions for SCTP
181 * 5.3.1.1 SCTP_ASSOC_CHANGE
182 *
183 * sac_error: 32 bits (signed integer)
184 *
185 * If the state was reached due to a error condition (e.g.
186 * COMMUNICATION_LOST) any relevant error information is available in
187 * this field. This corresponds to the protocol error codes defined in
188 * [SCTP].
189 */
190 sac->sac_error = error;
192 /* Socket Extensions for SCTP
193 * 5.3.1.1 SCTP_ASSOC_CHANGE
194 *
195 * sac_outbound_streams: 16 bits (unsigned integer)
196 * sac_inbound_streams: 16 bits (unsigned integer)
197 *
198 * The maximum number of streams allowed in each direction are
199 * available in sac_outbound_streams and sac_inbound streams.
200 */
201 sac->sac_outbound_streams = outbound;
202 sac->sac_inbound_streams = inbound;
204 /* Socket Extensions for SCTP
205 * 5.3.1.1 SCTP_ASSOC_CHANGE
206 *
207 * sac_assoc_id: sizeof (sctp_assoc_t)
208 *
209 * The association id field, holds the identifier for the association.
210 * All notifications for a given association have the same association
211 * identifier. For TCP style socket, this field is ignored.
212 */
213 sctp_ulpevent_set_owner(event, asoc);
214 sac->sac_assoc_id = sctp_assoc2id(asoc);
216 return event;
218 fail:
219 return NULL;
220 }
222 /* Create and initialize an SCTP_PEER_ADDR_CHANGE event.
223 *
224 * Socket Extensions for SCTP - draft-01
225 * 5.3.1.2 SCTP_PEER_ADDR_CHANGE
226 *
227 * When a destination address on a multi-homed peer encounters a change
228 * an interface details event is sent.
229 */
230 struct sctp_ulpevent *sctp_ulpevent_make_peer_addr_change(
231 const struct sctp_association *asoc,
232 const struct sockaddr_storage *aaddr,
233 int flags, int state, int error, gfp_t gfp)
234 {
235 struct sctp_ulpevent *event;
236 struct sctp_paddr_change *spc;
237 struct sk_buff *skb;
239 event = sctp_ulpevent_new(sizeof(struct sctp_paddr_change),
240 MSG_NOTIFICATION, gfp);
241 if (!event)
242 goto fail;
244 skb = sctp_event2skb(event);
245 spc = (struct sctp_paddr_change *)
246 skb_put(skb, sizeof(struct sctp_paddr_change));
248 /* Sockets API Extensions for SCTP
249 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
250 *
251 * spc_type:
252 *
253 * It should be SCTP_PEER_ADDR_CHANGE.
254 */
255 spc->spc_type = SCTP_PEER_ADDR_CHANGE;
257 /* Sockets API Extensions for SCTP
258 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
259 *
260 * spc_length: sizeof (__u32)
261 *
262 * This field is the total length of the notification data, including
263 * the notification header.
264 */
265 spc->spc_length = sizeof(struct sctp_paddr_change);
267 /* Sockets API Extensions for SCTP
268 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
269 *
270 * spc_flags: 16 bits (unsigned integer)
271 * Currently unused.
272 */
273 spc->spc_flags = 0;
275 /* Sockets API Extensions for SCTP
276 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
277 *
278 * spc_state: 32 bits (signed integer)
279 *
280 * This field holds one of a number of values that communicate the
281 * event that happened to the address.
282 */
283 spc->spc_state = state;
285 /* Sockets API Extensions for SCTP
286 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
287 *
288 * spc_error: 32 bits (signed integer)
289 *
290 * If the state was reached due to any error condition (e.g.
291 * ADDRESS_UNREACHABLE) any relevant error information is available in
292 * this field.
293 */
294 spc->spc_error = error;
296 /* Socket Extensions for SCTP
297 * 5.3.1.1 SCTP_ASSOC_CHANGE
298 *
299 * spc_assoc_id: sizeof (sctp_assoc_t)
300 *
301 * The association id field, holds the identifier for the association.
302 * All notifications for a given association have the same association
303 * identifier. For TCP style socket, this field is ignored.
304 */
305 sctp_ulpevent_set_owner(event, asoc);
306 spc->spc_assoc_id = sctp_assoc2id(asoc);
308 /* Sockets API Extensions for SCTP
309 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
310 *
311 * spc_aaddr: sizeof (struct sockaddr_storage)
312 *
313 * The affected address field, holds the remote peer's address that is
314 * encountering the change of state.
315 */
316 memcpy(&spc->spc_aaddr, aaddr, sizeof(struct sockaddr_storage));
318 /* Map ipv4 address into v4-mapped-on-v6 address. */
319 sctp_get_pf_specific(asoc->base.sk->sk_family)->addr_v4map(
320 sctp_sk(asoc->base.sk),
321 (union sctp_addr *)&spc->spc_aaddr);
323 return event;
325 fail:
326 return NULL;
327 }
329 /* Create and initialize an SCTP_REMOTE_ERROR notification.
330 *
331 * Note: This assumes that the chunk->skb->data already points to the
332 * operation error payload.
333 *
334 * Socket Extensions for SCTP - draft-01
335 * 5.3.1.3 SCTP_REMOTE_ERROR
336 *
337 * A remote peer may send an Operational Error message to its peer.
338 * This message indicates a variety of error conditions on an
339 * association. The entire error TLV as it appears on the wire is
340 * included in a SCTP_REMOTE_ERROR event. Please refer to the SCTP
341 * specification [SCTP] and any extensions for a list of possible
342 * error formats.
343 */
344 struct sctp_ulpevent *sctp_ulpevent_make_remote_error(
345 const struct sctp_association *asoc, struct sctp_chunk *chunk,
346 __u16 flags, gfp_t gfp)
347 {
348 struct sctp_ulpevent *event;
349 struct sctp_remote_error *sre;
350 struct sk_buff *skb;
351 sctp_errhdr_t *ch;
352 __u16 cause;
353 int elen;
355 ch = (sctp_errhdr_t *)(chunk->skb->data);
356 cause = ch->cause;
357 elen = WORD_ROUND(ntohs(ch->length)) - sizeof(sctp_errhdr_t);
359 /* Pull off the ERROR header. */
360 skb_pull(chunk->skb, sizeof(sctp_errhdr_t));
362 /* Copy the skb to a new skb with room for us to prepend
363 * notification with.
364 */
365 skb = skb_copy_expand(chunk->skb, sizeof(struct sctp_remote_error),
366 0, gfp);
368 /* Pull off the rest of the cause TLV from the chunk. */
369 skb_pull(chunk->skb, elen);
370 if (!skb)
371 goto fail;
373 /* Embed the event fields inside the cloned skb. */
374 event = sctp_skb2event(skb);
375 sctp_ulpevent_init(event, MSG_NOTIFICATION);
377 sre = (struct sctp_remote_error *)
378 skb_push(skb, sizeof(struct sctp_remote_error));
380 /* Trim the buffer to the right length. */
381 skb_trim(skb, sizeof(struct sctp_remote_error) + elen);
383 /* Socket Extensions for SCTP
384 * 5.3.1.3 SCTP_REMOTE_ERROR
385 *
386 * sre_type:
387 * It should be SCTP_REMOTE_ERROR.
388 */
389 sre->sre_type = SCTP_REMOTE_ERROR;
391 /*
392 * Socket Extensions for SCTP
393 * 5.3.1.3 SCTP_REMOTE_ERROR
394 *
395 * sre_flags: 16 bits (unsigned integer)
396 * Currently unused.
397 */
398 sre->sre_flags = 0;
400 /* Socket Extensions for SCTP
401 * 5.3.1.3 SCTP_REMOTE_ERROR
402 *
403 * sre_length: sizeof (__u32)
404 *
405 * This field is the total length of the notification data,
406 * including the notification header.
407 */
408 sre->sre_length = skb->len;
410 /* Socket Extensions for SCTP
411 * 5.3.1.3 SCTP_REMOTE_ERROR
412 *
413 * sre_error: 16 bits (unsigned integer)
414 * This value represents one of the Operational Error causes defined in
415 * the SCTP specification, in network byte order.
416 */
417 sre->sre_error = cause;
419 /* Socket Extensions for SCTP
420 * 5.3.1.3 SCTP_REMOTE_ERROR
421 *
422 * sre_assoc_id: sizeof (sctp_assoc_t)
423 *
424 * The association id field, holds the identifier for the association.
425 * All notifications for a given association have the same association
426 * identifier. For TCP style socket, this field is ignored.
427 */
428 sctp_ulpevent_set_owner(event, asoc);
429 sre->sre_assoc_id = sctp_assoc2id(asoc);
431 return event;
433 fail:
434 return NULL;
435 }
437 /* Create and initialize a SCTP_SEND_FAILED notification.
438 *
439 * Socket Extensions for SCTP - draft-01
440 * 5.3.1.4 SCTP_SEND_FAILED
441 */
442 struct sctp_ulpevent *sctp_ulpevent_make_send_failed(
443 const struct sctp_association *asoc, struct sctp_chunk *chunk,
444 __u16 flags, __u32 error, gfp_t gfp)
445 {
446 struct sctp_ulpevent *event;
447 struct sctp_send_failed *ssf;
448 struct sk_buff *skb;
450 /* Pull off any padding. */
451 int len = ntohs(chunk->chunk_hdr->length);
453 /* Make skb with more room so we can prepend notification. */
454 skb = skb_copy_expand(chunk->skb,
455 sizeof(struct sctp_send_failed), /* headroom */
456 0, /* tailroom */
457 gfp);
458 if (!skb)
459 goto fail;
461 /* Pull off the common chunk header and DATA header. */
462 skb_pull(skb, sizeof(struct sctp_data_chunk));
463 len -= sizeof(struct sctp_data_chunk);
465 /* Embed the event fields inside the cloned skb. */
466 event = sctp_skb2event(skb);
467 sctp_ulpevent_init(event, MSG_NOTIFICATION);
469 ssf = (struct sctp_send_failed *)
470 skb_push(skb, sizeof(struct sctp_send_failed));
472 /* Socket Extensions for SCTP
473 * 5.3.1.4 SCTP_SEND_FAILED
474 *
475 * ssf_type:
476 * It should be SCTP_SEND_FAILED.
477 */
478 ssf->ssf_type = SCTP_SEND_FAILED;
480 /* Socket Extensions for SCTP
481 * 5.3.1.4 SCTP_SEND_FAILED
482 *
483 * ssf_flags: 16 bits (unsigned integer)
484 * The flag value will take one of the following values
485 *
486 * SCTP_DATA_UNSENT - Indicates that the data was never put on
487 * the wire.
488 *
489 * SCTP_DATA_SENT - Indicates that the data was put on the wire.
490 * Note that this does not necessarily mean that the
491 * data was (or was not) successfully delivered.
492 */
493 ssf->ssf_flags = flags;
495 /* Socket Extensions for SCTP
496 * 5.3.1.4 SCTP_SEND_FAILED
497 *
498 * ssf_length: sizeof (__u32)
499 * This field is the total length of the notification data, including
500 * the notification header.
501 */
502 ssf->ssf_length = sizeof(struct sctp_send_failed) + len;
503 skb_trim(skb, ssf->ssf_length);
505 /* Socket Extensions for SCTP
506 * 5.3.1.4 SCTP_SEND_FAILED
507 *
508 * ssf_error: 16 bits (unsigned integer)
509 * This value represents the reason why the send failed, and if set,
510 * will be a SCTP protocol error code as defined in [SCTP] section
511 * 3.3.10.
512 */
513 ssf->ssf_error = error;
515 /* Socket Extensions for SCTP
516 * 5.3.1.4 SCTP_SEND_FAILED
517 *
518 * ssf_info: sizeof (struct sctp_sndrcvinfo)
519 * The original send information associated with the undelivered
520 * message.
521 */
522 memcpy(&ssf->ssf_info, &chunk->sinfo, sizeof(struct sctp_sndrcvinfo));
524 /* Per TSVWG discussion with Randy. Allow the application to
525 * ressemble a fragmented message.
526 */
527 ssf->ssf_info.sinfo_flags = chunk->chunk_hdr->flags;
529 /* Socket Extensions for SCTP
530 * 5.3.1.4 SCTP_SEND_FAILED
531 *
532 * ssf_assoc_id: sizeof (sctp_assoc_t)
533 * The association id field, sf_assoc_id, holds the identifier for the
534 * association. All notifications for a given association have the
535 * same association identifier. For TCP style socket, this field is
536 * ignored.
537 */
538 sctp_ulpevent_set_owner(event, asoc);
539 ssf->ssf_assoc_id = sctp_assoc2id(asoc);
540 return event;
542 fail:
543 return NULL;
544 }
546 /* Create and initialize a SCTP_SHUTDOWN_EVENT notification.
547 *
548 * Socket Extensions for SCTP - draft-01
549 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
550 */
551 struct sctp_ulpevent *sctp_ulpevent_make_shutdown_event(
552 const struct sctp_association *asoc,
553 __u16 flags, gfp_t gfp)
554 {
555 struct sctp_ulpevent *event;
556 struct sctp_shutdown_event *sse;
557 struct sk_buff *skb;
559 event = sctp_ulpevent_new(sizeof(struct sctp_shutdown_event),
560 MSG_NOTIFICATION, gfp);
561 if (!event)
562 goto fail;
564 skb = sctp_event2skb(event);
565 sse = (struct sctp_shutdown_event *)
566 skb_put(skb, sizeof(struct sctp_shutdown_event));
568 /* Socket Extensions for SCTP
569 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
570 *
571 * sse_type
572 * It should be SCTP_SHUTDOWN_EVENT
573 */
574 sse->sse_type = SCTP_SHUTDOWN_EVENT;
576 /* Socket Extensions for SCTP
577 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
578 *
579 * sse_flags: 16 bits (unsigned integer)
580 * Currently unused.
581 */
582 sse->sse_flags = 0;
584 /* Socket Extensions for SCTP
585 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
586 *
587 * sse_length: sizeof (__u32)
588 * This field is the total length of the notification data, including
589 * the notification header.
590 */
591 sse->sse_length = sizeof(struct sctp_shutdown_event);
593 /* Socket Extensions for SCTP
594 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
595 *
596 * sse_assoc_id: sizeof (sctp_assoc_t)
597 * The association id field, holds the identifier for the association.
598 * All notifications for a given association have the same association
599 * identifier. For TCP style socket, this field is ignored.
600 */
601 sctp_ulpevent_set_owner(event, asoc);
602 sse->sse_assoc_id = sctp_assoc2id(asoc);
604 return event;
606 fail:
607 return NULL;
608 }
610 /* Create and initialize a SCTP_ADAPTION_INDICATION notification.
611 *
612 * Socket Extensions for SCTP
613 * 5.3.1.6 SCTP_ADAPTION_INDICATION
614 */
615 struct sctp_ulpevent *sctp_ulpevent_make_adaption_indication(
616 const struct sctp_association *asoc, gfp_t gfp)
617 {
618 struct sctp_ulpevent *event;
619 struct sctp_adaption_event *sai;
620 struct sk_buff *skb;
622 event = sctp_ulpevent_new(sizeof(struct sctp_adaption_event),
623 MSG_NOTIFICATION, gfp);
624 if (!event)
625 goto fail;
627 skb = sctp_event2skb(event);
628 sai = (struct sctp_adaption_event *)
629 skb_put(skb, sizeof(struct sctp_adaption_event));
631 sai->sai_type = SCTP_ADAPTION_INDICATION;
632 sai->sai_flags = 0;
633 sai->sai_length = sizeof(struct sctp_adaption_event);
634 sai->sai_adaption_ind = asoc->peer.adaption_ind;
635 sctp_ulpevent_set_owner(event, asoc);
636 sai->sai_assoc_id = sctp_assoc2id(asoc);
638 return event;
640 fail:
641 return NULL;
642 }
644 /* A message has been received. Package this message as a notification
645 * to pass it to the upper layers. Go ahead and calculate the sndrcvinfo
646 * even if filtered out later.
647 *
648 * Socket Extensions for SCTP
649 * 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
650 */
651 struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc,
652 struct sctp_chunk *chunk,
653 gfp_t gfp)
654 {
655 struct sctp_ulpevent *event = NULL;
656 struct sk_buff *skb;
657 size_t padding, len;
659 /* Clone the original skb, sharing the data. */
660 skb = skb_clone(chunk->skb, gfp);
661 if (!skb)
662 goto fail;
664 /* First calculate the padding, so we don't inadvertently
665 * pass up the wrong length to the user.
666 *
667 * RFC 2960 - Section 3.2 Chunk Field Descriptions
668 *
669 * The total length of a chunk(including Type, Length and Value fields)
670 * MUST be a multiple of 4 bytes. If the length of the chunk is not a
671 * multiple of 4 bytes, the sender MUST pad the chunk with all zero
672 * bytes and this padding is not included in the chunk length field.
673 * The sender should never pad with more than 3 bytes. The receiver
674 * MUST ignore the padding bytes.
675 */
676 len = ntohs(chunk->chunk_hdr->length);
677 padding = WORD_ROUND(len) - len;
679 /* Fixup cloned skb with just this chunks data. */
680 skb_trim(skb, chunk->chunk_end - padding - skb->data);
682 /* Embed the event fields inside the cloned skb. */
683 event = sctp_skb2event(skb);
685 /* Initialize event with flags 0. */
686 sctp_ulpevent_init(event, 0);
688 sctp_ulpevent_receive_data(event, asoc);
690 event->stream = ntohs(chunk->subh.data_hdr->stream);
691 event->ssn = ntohs(chunk->subh.data_hdr->ssn);
692 event->ppid = chunk->subh.data_hdr->ppid;
693 if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
694 event->flags |= SCTP_UNORDERED;
695 event->cumtsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
696 }
697 event->tsn = ntohl(chunk->subh.data_hdr->tsn);
698 event->msg_flags |= chunk->chunk_hdr->flags;
699 event->iif = sctp_chunk_iif(chunk);
701 fail:
702 return event;
703 }
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 */
713 struct sctp_ulpevent *sctp_ulpevent_make_pdapi(
714 const struct sctp_association *asoc, __u32 indication,
715 gfp_t gfp)
716 {
717 struct sctp_ulpevent *event;
718 struct sctp_pdapi_event *pd;
719 struct sk_buff *skb;
721 event = sctp_ulpevent_new(sizeof(struct sctp_pdapi_event),
722 MSG_NOTIFICATION, gfp);
723 if (!event)
724 goto fail;
726 skb = sctp_event2skb(event);
727 pd = (struct sctp_pdapi_event *)
728 skb_put(skb, sizeof(struct sctp_pdapi_event));
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 = 0;
739 /* pdapi_length: 32 bits (unsigned integer)
740 *
741 * This field is the total length of the notification data, including
742 * the notification header. It will generally be sizeof (struct
743 * sctp_pdapi_event).
744 */
745 pd->pdapi_length = sizeof(struct sctp_pdapi_event);
747 /* pdapi_indication: 32 bits (unsigned integer)
748 *
749 * This field holds the indication being sent to the application.
750 */
751 pd->pdapi_indication = indication;
753 /* pdapi_assoc_id: sizeof (sctp_assoc_t)
754 *
755 * The association id field, holds the identifier for the association.
756 */
757 sctp_ulpevent_set_owner(event, asoc);
758 pd->pdapi_assoc_id = sctp_assoc2id(asoc);
760 return event;
761 fail:
762 return NULL;
763 }
765 /* Return the notification type, assuming this is a notification
766 * event.
767 */
768 __u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event)
769 {
770 union sctp_notification *notification;
771 struct sk_buff *skb;
773 skb = sctp_event2skb((struct sctp_ulpevent *)event);
774 notification = (union sctp_notification *) skb->data;
775 return notification->sn_header.sn_type;
776 }
778 /* Copy out the sndrcvinfo into a msghdr. */
779 void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
780 struct msghdr *msghdr)
781 {
782 struct sctp_sndrcvinfo sinfo;
784 if (sctp_ulpevent_is_notification(event))
785 return;
787 /* Sockets API Extensions for SCTP
788 * Section 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
789 *
790 * sinfo_stream: 16 bits (unsigned integer)
791 *
792 * For recvmsg() the SCTP stack places the message's stream number in
793 * this value.
794 */
795 sinfo.sinfo_stream = event->stream;
796 /* sinfo_ssn: 16 bits (unsigned integer)
797 *
798 * For recvmsg() this value contains the stream sequence number that
799 * the remote endpoint placed in the DATA chunk. For fragmented
800 * messages this is the same number for all deliveries of the message
801 * (if more than one recvmsg() is needed to read the message).
802 */
803 sinfo.sinfo_ssn = event->ssn;
804 /* sinfo_ppid: 32 bits (unsigned integer)
805 *
806 * In recvmsg() this value is
807 * the same information that was passed by the upper layer in the peer
808 * application. Please note that byte order issues are NOT accounted
809 * for and this information is passed opaquely by the SCTP stack from
810 * one end to the other.
811 */
812 sinfo.sinfo_ppid = event->ppid;
813 /* sinfo_flags: 16 bits (unsigned integer)
814 *
815 * This field may contain any of the following flags and is composed of
816 * a bitwise OR of these values.
817 *
818 * recvmsg() flags:
819 *
820 * SCTP_UNORDERED - This flag is present when the message was sent
821 * non-ordered.
822 */
823 sinfo.sinfo_flags = event->flags;
824 /* sinfo_tsn: 32 bit (unsigned integer)
825 *
826 * For the receiving side, this field holds a TSN that was
827 * assigned to one of the SCTP Data Chunks.
828 */
829 sinfo.sinfo_tsn = event->tsn;
830 /* sinfo_cumtsn: 32 bit (unsigned integer)
831 *
832 * This field will hold the current cumulative TSN as
833 * known by the underlying SCTP layer. Note this field is
834 * ignored when sending and only valid for a receive
835 * operation when sinfo_flags are set to SCTP_UNORDERED.
836 */
837 sinfo.sinfo_cumtsn = event->cumtsn;
838 /* sinfo_assoc_id: sizeof (sctp_assoc_t)
839 *
840 * The association handle field, sinfo_assoc_id, holds the identifier
841 * for the association announced in the COMMUNICATION_UP notification.
842 * All notifications for a given association have the same identifier.
843 * Ignored for one-to-one style sockets.
844 */
845 sinfo.sinfo_assoc_id = sctp_assoc2id(event->asoc);
847 /* These fields are not used while receiving. */
848 sinfo.sinfo_context = 0;
849 sinfo.sinfo_timetolive = 0;
851 put_cmsg(msghdr, IPPROTO_SCTP, SCTP_SNDRCV,
852 sizeof(struct sctp_sndrcvinfo), (void *)&sinfo);
853 }
855 /* Do accounting for bytes received and hold a reference to the association
856 * for each skb.
857 */
858 static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
859 struct sctp_association *asoc)
860 {
861 struct sk_buff *skb, *frag;
863 skb = sctp_event2skb(event);
864 /* Set the owner and charge rwnd for bytes received. */
865 sctp_ulpevent_set_owner(event, asoc);
866 sctp_assoc_rwnd_decrease(asoc, skb_headlen(skb));
868 if (!skb->data_len)
869 return;
871 /* Note: Not clearing the entire event struct as this is just a
872 * fragment of the real event. However, we still need to do rwnd
873 * accounting.
874 * In general, the skb passed from IP can have only 1 level of
875 * fragments. But we allow multiple levels of fragments.
876 */
877 for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) {
878 sctp_ulpevent_receive_data(sctp_skb2event(frag), asoc);
879 }
880 }
882 /* Do accounting for bytes just read by user and release the references to
883 * the association.
884 */
885 static void sctp_ulpevent_release_data(struct sctp_ulpevent *event)
886 {
887 struct sk_buff *skb, *frag;
888 unsigned int len;
890 /* Current stack structures assume that the rcv buffer is
891 * per socket. For UDP style sockets this is not true as
892 * multiple associations may be on a single UDP-style socket.
893 * Use the local private area of the skb to track the owning
894 * association.
895 */
897 skb = sctp_event2skb(event);
898 len = skb->len;
900 if (!skb->data_len)
901 goto done;
903 /* Don't forget the fragments. */
904 for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) {
905 /* NOTE: skb_shinfos are recursive. Although IP returns
906 * skb's with only 1 level of fragments, SCTP reassembly can
907 * increase the levels.
908 */
909 sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
910 }
912 done:
913 sctp_assoc_rwnd_increase(event->asoc, len);
914 sctp_ulpevent_release_owner(event);
915 }
917 static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event)
918 {
919 struct sk_buff *skb, *frag;
921 skb = sctp_event2skb(event);
923 if (!skb->data_len)
924 goto done;
926 /* Don't forget the fragments. */
927 for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) {
928 /* NOTE: skb_shinfos are recursive. Although IP returns
929 * skb's with only 1 level of fragments, SCTP reassembly can
930 * increase the levels.
931 */
932 sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
933 }
935 done:
936 sctp_ulpevent_release_owner(event);
937 }
939 /* Free a ulpevent that has an owner. It includes releasing the reference
940 * to the owner, updating the rwnd in case of a DATA event and freeing the
941 * skb.
942 */
943 void sctp_ulpevent_free(struct sctp_ulpevent *event)
944 {
945 if (sctp_ulpevent_is_notification(event))
946 sctp_ulpevent_release_owner(event);
947 else
948 sctp_ulpevent_release_data(event);
950 kfree_skb(sctp_event2skb(event));
951 }
953 /* Purge the skb lists holding ulpevents. */
954 void sctp_queue_purge_ulpevents(struct sk_buff_head *list)
955 {
956 struct sk_buff *skb;
957 while ((skb = skb_dequeue(list)) != NULL)
958 sctp_ulpevent_free(sctp_skb2event(skb));
959 }