ulpevent.c 30.3 KB
Newer Older
1
/* SCTP kernel implementation
L
Linus Torvalds 已提交
2 3 4 5 6 7 8 9 10
 * (C) Copyright IBM Corp. 2001, 2004
 * Copyright (c) 1999-2000 Cisco, Inc.
 * Copyright (c) 1999-2001 Motorola, Inc.
 * Copyright (c) 2001 Intel Corp.
 * Copyright (c) 2001 Nokia, Inc.
 * Copyright (c) 2001 La Monte H.P. Yarroll
 *
 * These functions manipulate an sctp event.   The struct ulpevent is used
 * to carry notifications and data to the ULP (sockets).
11 12
 *
 * This SCTP implementation is free software;
L
Linus Torvalds 已提交
13 14 15 16 17
 * you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
18
 * This SCTP implementation is distributed in the hope that it
L
Linus Torvalds 已提交
19 20 21 22 23 24
 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
 *                 ************************
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
25 26
 * along with GNU CC; see the file COPYING.  If not, see
 * <http://www.gnu.org/licenses/>.
L
Linus Torvalds 已提交
27 28 29
 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
30
 *    lksctp developers <linux-sctp@vger.kernel.org>
L
Linus Torvalds 已提交
31 32 33 34 35 36 37 38
 *
 * Written or modified by:
 *    Jon Grimm             <jgrimm@us.ibm.com>
 *    La Monte H.P. Yarroll <piggy@acm.org>
 *    Ardelle Fan	    <ardelle.fan@intel.com>
 *    Sridhar Samudrala     <sri@us.ibm.com>
 */

39
#include <linux/slab.h>
L
Linus Torvalds 已提交
40 41 42 43 44 45 46 47 48
#include <linux/types.h>
#include <linux/skbuff.h>
#include <net/sctp/structs.h>
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>

static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
				       struct sctp_association *asoc);
static void sctp_ulpevent_release_data(struct sctp_ulpevent *event);
49 50
static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event);

L
Linus Torvalds 已提交
51 52

/* Initialize an ULP event from an given skb.  */
53 54 55
static void sctp_ulpevent_init(struct sctp_ulpevent *event,
			       int msg_flags,
			       unsigned int len)
L
Linus Torvalds 已提交
56 57 58
{
	memset(event, 0, sizeof(struct sctp_ulpevent));
	event->msg_flags = msg_flags;
59
	event->rmem_len = len;
L
Linus Torvalds 已提交
60 61 62
}

/* Create a new sctp_ulpevent.  */
63 64
static struct sctp_ulpevent *sctp_ulpevent_new(int size, int msg_flags,
					       gfp_t gfp)
L
Linus Torvalds 已提交
65 66 67 68 69 70 71 72 73
{
	struct sctp_ulpevent *event;
	struct sk_buff *skb;

	skb = alloc_skb(size, gfp);
	if (!skb)
		goto fail;

	event = sctp_skb2event(skb);
74
	sctp_ulpevent_init(event, msg_flags, skb->truesize);
L
Linus Torvalds 已提交
75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101

	return event;

fail:
	return NULL;
}

/* Is this a MSG_NOTIFICATION?  */
int sctp_ulpevent_is_notification(const struct sctp_ulpevent *event)
{
	return MSG_NOTIFICATION == (event->msg_flags & MSG_NOTIFICATION);
}

/* Hold the association in case the msg_name needs read out of
 * the association.
 */
static inline void sctp_ulpevent_set_owner(struct sctp_ulpevent *event,
					   const struct sctp_association *asoc)
{
	struct sk_buff *skb;

	/* Cast away the const, as we are just wanting to
	 * bump the reference count.
	 */
	sctp_association_hold((struct sctp_association *)asoc);
	skb = sctp_event2skb(event);
	event->asoc = (struct sctp_association *)asoc;
102 103
	atomic_add(event->rmem_len, &event->asoc->rmem_alloc);
	sctp_skb_set_owner_r(skb, asoc->base.sk);
L
Linus Torvalds 已提交
104 105 106 107 108
}

/* A simple destructor to give up the reference to the association. */
static inline void sctp_ulpevent_release_owner(struct sctp_ulpevent *event)
{
109 110
	struct sctp_association *asoc = event->asoc;

111
	atomic_sub(event->rmem_len, &asoc->rmem_alloc);
112
	sctp_association_put(asoc);
L
Linus Torvalds 已提交
113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128
}

/* Create and initialize an SCTP_ASSOC_CHANGE event.
 *
 * 5.3.1.1 SCTP_ASSOC_CHANGE
 *
 * Communication notifications inform the ULP that an SCTP association
 * has either begun or ended. The identifier for a new association is
 * provided by this notification.
 *
 * Note: There is no field checking here.  If a field is unused it will be
 * zero'd out.
 */
struct sctp_ulpevent  *sctp_ulpevent_make_assoc_change(
	const struct sctp_association *asoc,
	__u16 flags, __u16 state, __u16 error, __u16 outbound,
129
	__u16 inbound, struct sctp_chunk *chunk, gfp_t gfp)
L
Linus Torvalds 已提交
130 131 132 133 134
{
	struct sctp_ulpevent *event;
	struct sctp_assoc_change *sac;
	struct sk_buff *skb;

135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157
	/* If the lower layer passed in the chunk, it will be
	 * an ABORT, so we need to include it in the sac_info.
	 */
	if (chunk) {
		/* Copy the chunk data to a new skb and reserve enough
		 * head room to use as notification.
		 */
		skb = skb_copy_expand(chunk->skb,
				      sizeof(struct sctp_assoc_change), 0, gfp);

		if (!skb)
			goto fail;

		/* Embed the event fields inside the cloned skb.  */
		event = sctp_skb2event(skb);
		sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);

		/* Include the notification structure */
		sac = (struct sctp_assoc_change *)
			skb_push(skb, sizeof(struct sctp_assoc_change));

		/* Trim the buffer to the right length.  */
		skb_trim(skb, sizeof(struct sctp_assoc_change) +
158 159
			 ntohs(chunk->chunk_hdr->length) -
			 sizeof(sctp_chunkhdr_t));
160 161
	} else {
		event = sctp_ulpevent_new(sizeof(struct sctp_assoc_change),
L
Linus Torvalds 已提交
162
				  MSG_NOTIFICATION, gfp);
163 164 165 166 167 168 169
		if (!event)
			goto fail;

		skb = sctp_event2skb(event);
		sac = (struct sctp_assoc_change *) skb_put(skb,
					sizeof(struct sctp_assoc_change));
	}
L
Linus Torvalds 已提交
170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202

	/* Socket Extensions for SCTP
	 * 5.3.1.1 SCTP_ASSOC_CHANGE
	 *
	 * sac_type:
	 * It should be SCTP_ASSOC_CHANGE.
	 */
	sac->sac_type = SCTP_ASSOC_CHANGE;

	/* Socket Extensions for SCTP
	 * 5.3.1.1 SCTP_ASSOC_CHANGE
	 *
	 * sac_state: 32 bits (signed integer)
	 * This field holds one of a number of values that communicate the
	 * event that happened to the association.
	 */
	sac->sac_state = state;

	/* Socket Extensions for SCTP
	 * 5.3.1.1 SCTP_ASSOC_CHANGE
	 *
	 * sac_flags: 16 bits (unsigned integer)
	 * Currently unused.
	 */
	sac->sac_flags = 0;

	/* Socket Extensions for SCTP
	 * 5.3.1.1 SCTP_ASSOC_CHANGE
	 *
	 * sac_length: sizeof (__u32)
	 * This field is the total length of the notification data, including
	 * the notification header.
	 */
203
	sac->sac_length = skb->len;
L
Linus Torvalds 已提交
204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257

	/* Socket Extensions for SCTP
	 * 5.3.1.1 SCTP_ASSOC_CHANGE
	 *
	 * sac_error:  32 bits (signed integer)
	 *
	 * If the state was reached due to a error condition (e.g.
	 * COMMUNICATION_LOST) any relevant error information is available in
	 * this field. This corresponds to the protocol error codes defined in
	 * [SCTP].
	 */
	sac->sac_error = error;

	/* Socket Extensions for SCTP
	 * 5.3.1.1 SCTP_ASSOC_CHANGE
	 *
	 * sac_outbound_streams:  16 bits (unsigned integer)
	 * sac_inbound_streams:  16 bits (unsigned integer)
	 *
	 * The maximum number of streams allowed in each direction are
	 * available in sac_outbound_streams and sac_inbound streams.
	 */
	sac->sac_outbound_streams = outbound;
	sac->sac_inbound_streams = inbound;

	/* Socket Extensions for SCTP
	 * 5.3.1.1 SCTP_ASSOC_CHANGE
	 *
	 * sac_assoc_id: sizeof (sctp_assoc_t)
	 *
	 * The association id field, holds the identifier for the association.
	 * All notifications for a given association have the same association
	 * identifier.  For TCP style socket, this field is ignored.
	 */
	sctp_ulpevent_set_owner(event, asoc);
	sac->sac_assoc_id = sctp_assoc2id(asoc);

	return event;

fail:
	return NULL;
}

/* Create and initialize an SCTP_PEER_ADDR_CHANGE event.
 *
 * Socket Extensions for SCTP - draft-01
 * 5.3.1.2 SCTP_PEER_ADDR_CHANGE
 *
 * When a destination address on a multi-homed peer encounters a change
 * an interface details event is sent.
 */
struct sctp_ulpevent *sctp_ulpevent_make_peer_addr_change(
	const struct sctp_association *asoc,
	const struct sockaddr_storage *aaddr,
A
Al Viro 已提交
258
	int flags, int state, int error, gfp_t gfp)
L
Linus Torvalds 已提交
259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370
{
	struct sctp_ulpevent *event;
	struct sctp_paddr_change  *spc;
	struct sk_buff *skb;

	event = sctp_ulpevent_new(sizeof(struct sctp_paddr_change),
				  MSG_NOTIFICATION, gfp);
	if (!event)
		goto fail;

	skb = sctp_event2skb(event);
	spc = (struct sctp_paddr_change *)
		skb_put(skb, sizeof(struct sctp_paddr_change));

	/* Sockets API Extensions for SCTP
	 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
	 *
	 * spc_type:
	 *
	 *    It should be SCTP_PEER_ADDR_CHANGE.
	 */
	spc->spc_type = SCTP_PEER_ADDR_CHANGE;

	/* Sockets API Extensions for SCTP
	 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
	 *
	 * spc_length: sizeof (__u32)
	 *
	 * This field is the total length of the notification data, including
	 * the notification header.
	 */
	spc->spc_length = sizeof(struct sctp_paddr_change);

	/* Sockets API Extensions for SCTP
	 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
	 *
	 * spc_flags: 16 bits (unsigned integer)
	 * Currently unused.
	 */
	spc->spc_flags = 0;

	/* Sockets API Extensions for SCTP
	 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
	 *
	 * spc_state:  32 bits (signed integer)
	 *
	 * This field holds one of a number of values that communicate the
	 * event that happened to the address.
	 */
	spc->spc_state = state;

	/* Sockets API Extensions for SCTP
	 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
	 *
	 * spc_error:  32 bits (signed integer)
	 *
	 * If the state was reached due to any error condition (e.g.
	 * ADDRESS_UNREACHABLE) any relevant error information is available in
	 * this field.
	 */
	spc->spc_error = error;

	/* Socket Extensions for SCTP
	 * 5.3.1.1 SCTP_ASSOC_CHANGE
	 *
	 * spc_assoc_id: sizeof (sctp_assoc_t)
	 *
	 * The association id field, holds the identifier for the association.
	 * All notifications for a given association have the same association
	 * identifier.  For TCP style socket, this field is ignored.
	 */
	sctp_ulpevent_set_owner(event, asoc);
	spc->spc_assoc_id = sctp_assoc2id(asoc);

	/* Sockets API Extensions for SCTP
	 * Section 5.3.1.2 SCTP_PEER_ADDR_CHANGE
	 *
	 * spc_aaddr: sizeof (struct sockaddr_storage)
	 *
	 * The affected address field, holds the remote peer's address that is
	 * encountering the change of state.
	 */
	memcpy(&spc->spc_aaddr, aaddr, sizeof(struct sockaddr_storage));

	/* Map ipv4 address into v4-mapped-on-v6 address.  */
	sctp_get_pf_specific(asoc->base.sk->sk_family)->addr_v4map(
					sctp_sk(asoc->base.sk),
					(union sctp_addr *)&spc->spc_aaddr);

	return event;

fail:
	return NULL;
}

/* Create and initialize an SCTP_REMOTE_ERROR notification.
 *
 * Note: This assumes that the chunk->skb->data already points to the
 * operation error payload.
 *
 * Socket Extensions for SCTP - draft-01
 * 5.3.1.3 SCTP_REMOTE_ERROR
 *
 * A remote peer may send an Operational Error message to its peer.
 * This message indicates a variety of error conditions on an
 * association. The entire error TLV as it appears on the wire is
 * included in a SCTP_REMOTE_ERROR event.  Please refer to the SCTP
 * specification [SCTP] and any extensions for a list of possible
 * error formats.
 */
struct sctp_ulpevent *sctp_ulpevent_make_remote_error(
	const struct sctp_association *asoc, struct sctp_chunk *chunk,
A
Al Viro 已提交
371
	__u16 flags, gfp_t gfp)
L
Linus Torvalds 已提交
372 373 374 375 376
{
	struct sctp_ulpevent *event;
	struct sctp_remote_error *sre;
	struct sk_buff *skb;
	sctp_errhdr_t *ch;
A
Al Viro 已提交
377
	__be16 cause;
L
Linus Torvalds 已提交
378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399
	int elen;

	ch = (sctp_errhdr_t *)(chunk->skb->data);
	cause = ch->cause;
	elen = WORD_ROUND(ntohs(ch->length)) - sizeof(sctp_errhdr_t);

	/* Pull off the ERROR header.  */
	skb_pull(chunk->skb, sizeof(sctp_errhdr_t));

	/* Copy the skb to a new skb with room for us to prepend
	 * notification with.
	 */
	skb = skb_copy_expand(chunk->skb, sizeof(struct sctp_remote_error),
			      0, gfp);

	/* Pull off the rest of the cause TLV from the chunk.  */
	skb_pull(chunk->skb, elen);
	if (!skb)
		goto fail;

	/* Embed the event fields inside the cloned skb.  */
	event = sctp_skb2event(skb);
400
	sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
L
Linus Torvalds 已提交
401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468

	sre = (struct sctp_remote_error *)
		skb_push(skb, sizeof(struct sctp_remote_error));

	/* Trim the buffer to the right length.  */
	skb_trim(skb, sizeof(struct sctp_remote_error) + elen);

	/* Socket Extensions for SCTP
	 * 5.3.1.3 SCTP_REMOTE_ERROR
	 *
	 * sre_type:
	 *   It should be SCTP_REMOTE_ERROR.
	 */
	sre->sre_type = SCTP_REMOTE_ERROR;

	/*
	 * Socket Extensions for SCTP
	 * 5.3.1.3 SCTP_REMOTE_ERROR
	 *
	 * sre_flags: 16 bits (unsigned integer)
	 *   Currently unused.
	 */
	sre->sre_flags = 0;

	/* Socket Extensions for SCTP
	 * 5.3.1.3 SCTP_REMOTE_ERROR
	 *
	 * sre_length: sizeof (__u32)
	 *
	 * This field is the total length of the notification data,
	 * including the notification header.
	 */
	sre->sre_length = skb->len;

	/* Socket Extensions for SCTP
	 * 5.3.1.3 SCTP_REMOTE_ERROR
	 *
	 * sre_error: 16 bits (unsigned integer)
	 * This value represents one of the Operational Error causes defined in
	 * the SCTP specification, in network byte order.
	 */
	sre->sre_error = cause;

	/* Socket Extensions for SCTP
	 * 5.3.1.3 SCTP_REMOTE_ERROR
	 *
	 * sre_assoc_id: sizeof (sctp_assoc_t)
	 *
	 * The association id field, holds the identifier for the association.
	 * All notifications for a given association have the same association
	 * identifier.  For TCP style socket, this field is ignored.
	 */
	sctp_ulpevent_set_owner(event, asoc);
	sre->sre_assoc_id = sctp_assoc2id(asoc);

	return event;

fail:
	return NULL;
}

/* Create and initialize a SCTP_SEND_FAILED notification.
 *
 * Socket Extensions for SCTP - draft-01
 * 5.3.1.4 SCTP_SEND_FAILED
 */
struct sctp_ulpevent *sctp_ulpevent_make_send_failed(
	const struct sctp_association *asoc, struct sctp_chunk *chunk,
A
Al Viro 已提交
469
	__u16 flags, __u32 error, gfp_t gfp)
L
Linus Torvalds 已提交
470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491
{
	struct sctp_ulpevent *event;
	struct sctp_send_failed *ssf;
	struct sk_buff *skb;

	/* Pull off any padding. */
	int len = ntohs(chunk->chunk_hdr->length);

	/* Make skb with more room so we can prepend notification.  */
	skb = skb_copy_expand(chunk->skb,
			      sizeof(struct sctp_send_failed), /* headroom */
			      0,                               /* tailroom */
			      gfp);
	if (!skb)
		goto fail;

	/* Pull off the common chunk header and DATA header.  */
	skb_pull(skb, sizeof(struct sctp_data_chunk));
	len -= sizeof(struct sctp_data_chunk);

	/* Embed the event fields inside the cloned skb.  */
	event = sctp_skb2event(skb);
492
	sctp_ulpevent_init(event, MSG_NOTIFICATION, skb->truesize);
L
Linus Torvalds 已提交
493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549

	ssf = (struct sctp_send_failed *)
		skb_push(skb, sizeof(struct sctp_send_failed));

	/* Socket Extensions for SCTP
	 * 5.3.1.4 SCTP_SEND_FAILED
	 *
	 * ssf_type:
	 * It should be SCTP_SEND_FAILED.
	 */
	ssf->ssf_type = SCTP_SEND_FAILED;

	/* Socket Extensions for SCTP
	 * 5.3.1.4 SCTP_SEND_FAILED
	 *
	 * ssf_flags: 16 bits (unsigned integer)
	 * The flag value will take one of the following values
	 *
	 * SCTP_DATA_UNSENT - Indicates that the data was never put on
	 *                    the wire.
	 *
	 * SCTP_DATA_SENT   - Indicates that the data was put on the wire.
	 *                    Note that this does not necessarily mean that the
	 *                    data was (or was not) successfully delivered.
	 */
	ssf->ssf_flags = flags;

	/* Socket Extensions for SCTP
	 * 5.3.1.4 SCTP_SEND_FAILED
	 *
	 * ssf_length: sizeof (__u32)
	 * This field is the total length of the notification data, including
	 * the notification header.
	 */
	ssf->ssf_length = sizeof(struct sctp_send_failed) + len;
	skb_trim(skb, ssf->ssf_length);

	/* Socket Extensions for SCTP
	 * 5.3.1.4 SCTP_SEND_FAILED
	 *
	 * ssf_error: 16 bits (unsigned integer)
	 * This value represents the reason why the send failed, and if set,
	 * will be a SCTP protocol error code as defined in [SCTP] section
	 * 3.3.10.
	 */
	ssf->ssf_error = error;

	/* Socket Extensions for SCTP
	 * 5.3.1.4 SCTP_SEND_FAILED
	 *
	 * ssf_info: sizeof (struct sctp_sndrcvinfo)
	 * The original send information associated with the undelivered
	 * message.
	 */
	memcpy(&ssf->ssf_info, &chunk->sinfo, sizeof(struct sctp_sndrcvinfo));

	/* Per TSVWG discussion with Randy. Allow the application to
550
	 * reassemble a fragmented message.
L
Linus Torvalds 已提交
551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577
	 */
	ssf->ssf_info.sinfo_flags = chunk->chunk_hdr->flags;

	/* Socket Extensions for SCTP
	 * 5.3.1.4 SCTP_SEND_FAILED
	 *
	 * ssf_assoc_id: sizeof (sctp_assoc_t)
	 * The association id field, sf_assoc_id, holds the identifier for the
	 * association.  All notifications for a given association have the
	 * same association identifier.  For TCP style socket, this field is
	 * ignored.
	 */
	sctp_ulpevent_set_owner(event, asoc);
	ssf->ssf_assoc_id = sctp_assoc2id(asoc);
	return event;

fail:
	return NULL;
}

/* Create and initialize a SCTP_SHUTDOWN_EVENT notification.
 *
 * Socket Extensions for SCTP - draft-01
 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
 */
struct sctp_ulpevent *sctp_ulpevent_make_shutdown_event(
	const struct sctp_association *asoc,
A
Al Viro 已提交
578
	__u16 flags, gfp_t gfp)
L
Linus Torvalds 已提交
579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634
{
	struct sctp_ulpevent *event;
	struct sctp_shutdown_event *sse;
	struct sk_buff *skb;

	event = sctp_ulpevent_new(sizeof(struct sctp_shutdown_event),
				  MSG_NOTIFICATION, gfp);
	if (!event)
		goto fail;

	skb = sctp_event2skb(event);
	sse = (struct sctp_shutdown_event *)
		skb_put(skb, sizeof(struct sctp_shutdown_event));

	/* Socket Extensions for SCTP
	 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
	 *
	 * sse_type
	 * It should be SCTP_SHUTDOWN_EVENT
	 */
	sse->sse_type = SCTP_SHUTDOWN_EVENT;

	/* Socket Extensions for SCTP
	 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
	 *
	 * sse_flags: 16 bits (unsigned integer)
	 * Currently unused.
	 */
	sse->sse_flags = 0;

	/* Socket Extensions for SCTP
	 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
	 *
	 * sse_length: sizeof (__u32)
	 * This field is the total length of the notification data, including
	 * the notification header.
	 */
	sse->sse_length = sizeof(struct sctp_shutdown_event);

	/* Socket Extensions for SCTP
	 * 5.3.1.5 SCTP_SHUTDOWN_EVENT
	 *
	 * sse_assoc_id: sizeof (sctp_assoc_t)
	 * The association id field, holds the identifier for the association.
	 * All notifications for a given association have the same association
	 * identifier.  For TCP style socket, this field is ignored.
	 */
	sctp_ulpevent_set_owner(event, asoc);
	sse->sse_assoc_id = sctp_assoc2id(asoc);

	return event;

fail:
	return NULL;
}

635
/* Create and initialize a SCTP_ADAPTATION_INDICATION notification.
L
Linus Torvalds 已提交
636 637
 *
 * Socket Extensions for SCTP
638
 * 5.3.1.6 SCTP_ADAPTATION_INDICATION
L
Linus Torvalds 已提交
639
 */
640
struct sctp_ulpevent *sctp_ulpevent_make_adaptation_indication(
A
Al Viro 已提交
641
	const struct sctp_association *asoc, gfp_t gfp)
L
Linus Torvalds 已提交
642 643
{
	struct sctp_ulpevent *event;
644
	struct sctp_adaptation_event *sai;
L
Linus Torvalds 已提交
645 646
	struct sk_buff *skb;

647
	event = sctp_ulpevent_new(sizeof(struct sctp_adaptation_event),
L
Linus Torvalds 已提交
648 649 650 651 652
				  MSG_NOTIFICATION, gfp);
	if (!event)
		goto fail;

	skb = sctp_event2skb(event);
653 654
	sai = (struct sctp_adaptation_event *)
		skb_put(skb, sizeof(struct sctp_adaptation_event));
L
Linus Torvalds 已提交
655

656
	sai->sai_type = SCTP_ADAPTATION_INDICATION;
L
Linus Torvalds 已提交
657
	sai->sai_flags = 0;
658 659
	sai->sai_length = sizeof(struct sctp_adaptation_event);
	sai->sai_adaptation_ind = asoc->peer.adaptation_ind;
L
Linus Torvalds 已提交
660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677
	sctp_ulpevent_set_owner(event, asoc);
	sai->sai_assoc_id = sctp_assoc2id(asoc);

	return event;

fail:
	return NULL;
}

/* A message has been received.  Package this message as a notification
 * to pass it to the upper layers.  Go ahead and calculate the sndrcvinfo
 * even if filtered out later.
 *
 * Socket Extensions for SCTP
 * 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
 */
struct sctp_ulpevent *sctp_ulpevent_make_rcvmsg(struct sctp_association *asoc,
						struct sctp_chunk *chunk,
A
Al Viro 已提交
678
						gfp_t gfp)
L
Linus Torvalds 已提交
679 680 681 682
{
	struct sctp_ulpevent *event = NULL;
	struct sk_buff *skb;
	size_t padding, len;
683 684 685 686 687 688 689 690 691 692 693 694 695 696 697
	int rx_count;

	/*
	 * check to see if we need to make space for this
	 * new skb, expand the rcvbuffer if needed, or drop
	 * the frame
	 */
	if (asoc->ep->rcvbuf_policy)
		rx_count = atomic_read(&asoc->rmem_alloc);
	else
		rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);

	if (rx_count >= asoc->base.sk->sk_rcvbuf) {

		if ((asoc->base.sk->sk_userlocks & SOCK_RCVBUF_LOCK) ||
698 699
		    (!sk_rmem_schedule(asoc->base.sk, chunk->skb,
				       chunk->skb->truesize)))
700 701
			goto fail;
	}
L
Linus Torvalds 已提交
702 703 704 705 706 707

	/* Clone the original skb, sharing the data.  */
	skb = skb_clone(chunk->skb, gfp);
	if (!skb)
		goto fail;

708 709 710
	/* Now that all memory allocations for this chunk succeeded, we
	 * can mark it as received so the tsn_map is updated correctly.
	 */
711
	if (sctp_tsnmap_mark(&asoc->peer.tsn_map,
712 713
			     ntohl(chunk->subh.data_hdr->tsn),
			     chunk->transport))
714
		goto fail_mark;
715

L
Linus Torvalds 已提交
716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736
	/* First calculate the padding, so we don't inadvertently
	 * pass up the wrong length to the user.
	 *
	 * RFC 2960 - Section 3.2  Chunk Field Descriptions
	 *
	 * The total length of a chunk(including Type, Length and Value fields)
	 * MUST be a multiple of 4 bytes.  If the length of the chunk is not a
	 * multiple of 4 bytes, the sender MUST pad the chunk with all zero
	 * bytes and this padding is not included in the chunk length field.
	 * The sender should never pad with more than 3 bytes.  The receiver
	 * MUST ignore the padding bytes.
	 */
	len = ntohs(chunk->chunk_hdr->length);
	padding = WORD_ROUND(len) - len;

	/* Fixup cloned skb with just this chunks data.  */
	skb_trim(skb, chunk->chunk_end - padding - skb->data);

	/* Embed the event fields inside the cloned skb.  */
	event = sctp_skb2event(skb);

737 738 739 740 741
	/* Initialize event with flags 0  and correct length
	 * Since this is a clone of the original skb, only account for
	 * the data of this chunk as other chunks will be accounted separately.
	 */
	sctp_ulpevent_init(event, 0, skb->len + sizeof(struct sk_buff));
L
Linus Torvalds 已提交
742 743 744 745 746 747 748

	sctp_ulpevent_receive_data(event, asoc);

	event->stream = ntohs(chunk->subh.data_hdr->stream);
	event->ssn = ntohs(chunk->subh.data_hdr->ssn);
	event->ppid = chunk->subh.data_hdr->ppid;
	if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) {
749
		event->flags |= SCTP_UNORDERED;
L
Linus Torvalds 已提交
750 751 752 753 754 755 756
		event->cumtsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map);
	}
	event->tsn = ntohl(chunk->subh.data_hdr->tsn);
	event->msg_flags |= chunk->chunk_hdr->flags;
	event->iif = sctp_chunk_iif(chunk);

	return event;
757 758 759 760 761

fail_mark:
	kfree_skb(skb);
fail:
	return NULL;
L
Linus Torvalds 已提交
762 763 764 765 766 767 768 769 770 771 772
}

/* Create a partial delivery related event.
 *
 * 5.3.1.7 SCTP_PARTIAL_DELIVERY_EVENT
 *
 *   When a receiver is engaged in a partial delivery of a
 *   message this notification will be used to indicate
 *   various events.
 */
struct sctp_ulpevent *sctp_ulpevent_make_pdapi(
A
Alexey Dobriyan 已提交
773
	const struct sctp_association *asoc, __u32 indication,
A
Al Viro 已提交
774
	gfp_t gfp)
L
Linus Torvalds 已提交
775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805
{
	struct sctp_ulpevent *event;
	struct sctp_pdapi_event *pd;
	struct sk_buff *skb;

	event = sctp_ulpevent_new(sizeof(struct sctp_pdapi_event),
				  MSG_NOTIFICATION, gfp);
	if (!event)
		goto fail;

	skb = sctp_event2skb(event);
	pd = (struct sctp_pdapi_event *)
		skb_put(skb, sizeof(struct sctp_pdapi_event));

	/* pdapi_type
	 *   It should be SCTP_PARTIAL_DELIVERY_EVENT
	 *
	 * pdapi_flags: 16 bits (unsigned integer)
	 *   Currently unused.
	 */
	pd->pdapi_type = SCTP_PARTIAL_DELIVERY_EVENT;
	pd->pdapi_flags = 0;

	/* pdapi_length: 32 bits (unsigned integer)
	 *
	 * This field is the total length of the notification data, including
	 * the notification header.  It will generally be sizeof (struct
	 * sctp_pdapi_event).
	 */
	pd->pdapi_length = sizeof(struct sctp_pdapi_event);

806
	/*  pdapi_indication: 32 bits (unsigned integer)
L
Linus Torvalds 已提交
807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823
	 *
	 * This field holds the indication being sent to the application.
	 */
	pd->pdapi_indication = indication;

	/*  pdapi_assoc_id: sizeof (sctp_assoc_t)
	 *
	 * The association id field, holds the identifier for the association.
	 */
	sctp_ulpevent_set_owner(event, asoc);
	pd->pdapi_assoc_id = sctp_assoc2id(asoc);

	return event;
fail:
	return NULL;
}

824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840
struct sctp_ulpevent *sctp_ulpevent_make_authkey(
	const struct sctp_association *asoc, __u16 key_id,
	__u32 indication, gfp_t gfp)
{
	struct sctp_ulpevent *event;
	struct sctp_authkey_event *ak;
	struct sk_buff *skb;

	event = sctp_ulpevent_new(sizeof(struct sctp_authkey_event),
				  MSG_NOTIFICATION, gfp);
	if (!event)
		goto fail;

	skb = sctp_event2skb(event);
	ak = (struct sctp_authkey_event *)
		skb_put(skb, sizeof(struct sctp_authkey_event));

841
	ak->auth_type = SCTP_AUTHENTICATION_EVENT;
842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859
	ak->auth_flags = 0;
	ak->auth_length = sizeof(struct sctp_authkey_event);

	ak->auth_keynumber = key_id;
	ak->auth_altkeynumber = 0;
	ak->auth_indication = indication;

	/*
	 * The association id field, holds the identifier for the association.
	 */
	sctp_ulpevent_set_owner(event, asoc);
	ak->auth_assoc_id = sctp_assoc2id(asoc);

	return event;
fail:
	return NULL;
}

860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887
/*
 * Socket Extensions for SCTP
 * 6.3.10. SCTP_SENDER_DRY_EVENT
 */
struct sctp_ulpevent *sctp_ulpevent_make_sender_dry_event(
	const struct sctp_association *asoc, gfp_t gfp)
{
	struct sctp_ulpevent *event;
	struct sctp_sender_dry_event *sdry;
	struct sk_buff *skb;

	event = sctp_ulpevent_new(sizeof(struct sctp_sender_dry_event),
				  MSG_NOTIFICATION, gfp);
	if (!event)
		return NULL;

	skb = sctp_event2skb(event);
	sdry = (struct sctp_sender_dry_event *)
		skb_put(skb, sizeof(struct sctp_sender_dry_event));

	sdry->sender_dry_type = SCTP_SENDER_DRY_EVENT;
	sdry->sender_dry_flags = 0;
	sdry->sender_dry_length = sizeof(struct sctp_sender_dry_event);
	sctp_ulpevent_set_owner(event, asoc);
	sdry->sender_dry_assoc_id = sctp_assoc2id(asoc);

	return event;
}
888

L
Linus Torvalds 已提交
889 890 891 892 893 894 895 896
/* Return the notification type, assuming this is a notification
 * event.
 */
__u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event)
{
	union sctp_notification *notification;
	struct sk_buff *skb;

897
	skb = sctp_event2skb(event);
L
Linus Torvalds 已提交
898 899 900 901 902 903 904 905 906 907 908 909 910 911
	notification = (union sctp_notification *) skb->data;
	return notification->sn_header.sn_type;
}

/* Copy out the sndrcvinfo into a msghdr.  */
void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
				   struct msghdr *msghdr)
{
	struct sctp_sndrcvinfo sinfo;

	if (sctp_ulpevent_is_notification(event))
		return;

	/* Sockets API Extensions for SCTP
912 913 914 915 916 917 918
	 * Section 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
	 *
	 * sinfo_stream: 16 bits (unsigned integer)
	 *
	 * For recvmsg() the SCTP stack places the message's stream number in
	 * this value.
	*/
L
Linus Torvalds 已提交
919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943
	sinfo.sinfo_stream = event->stream;
	/* sinfo_ssn: 16 bits (unsigned integer)
	 *
	 * For recvmsg() this value contains the stream sequence number that
	 * the remote endpoint placed in the DATA chunk.  For fragmented
	 * messages this is the same number for all deliveries of the message
	 * (if more than one recvmsg() is needed to read the message).
	 */
	sinfo.sinfo_ssn = event->ssn;
	/* sinfo_ppid: 32 bits (unsigned integer)
	 *
	 * In recvmsg() this value is
	 * the same information that was passed by the upper layer in the peer
	 * application.  Please note that byte order issues are NOT accounted
	 * for and this information is passed opaquely by the SCTP stack from
	 * one end to the other.
	 */
	sinfo.sinfo_ppid = event->ppid;
	/* sinfo_flags: 16 bits (unsigned integer)
	 *
	 * This field may contain any of the following flags and is composed of
	 * a bitwise OR of these values.
	 *
	 * recvmsg() flags:
	 *
944
	 * SCTP_UNORDERED - This flag is present when the message was sent
L
Linus Torvalds 已提交
945 946 947 948 949
	 *                 non-ordered.
	 */
	sinfo.sinfo_flags = event->flags;
	/* sinfo_tsn: 32 bit (unsigned integer)
	 *
950
	 * For the receiving side, this field holds a TSN that was
L
Linus Torvalds 已提交
951 952 953 954 955 956 957 958
	 * assigned to one of the SCTP Data Chunks.
	 */
	sinfo.sinfo_tsn = event->tsn;
	/* sinfo_cumtsn: 32 bit (unsigned integer)
	 *
	 * This field will hold the current cumulative TSN as
	 * known by the underlying SCTP layer.  Note this field is
	 * ignored when sending and only valid for a receive
959
	 * operation when sinfo_flags are set to SCTP_UNORDERED.
L
Linus Torvalds 已提交
960 961 962 963 964 965 966 967 968 969 970
	 */
	sinfo.sinfo_cumtsn = event->cumtsn;
	/* sinfo_assoc_id: sizeof (sctp_assoc_t)
	 *
	 * The association handle field, sinfo_assoc_id, holds the identifier
	 * for the association announced in the COMMUNICATION_UP notification.
	 * All notifications for a given association have the same identifier.
	 * Ignored for one-to-one style sockets.
	 */
	sinfo.sinfo_assoc_id = sctp_assoc2id(event->asoc);

971 972 973
	/* context value that is set via SCTP_CONTEXT socket option. */
	sinfo.sinfo_context = event->asoc->default_rcv_context;

L
Linus Torvalds 已提交
974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991
	/* These fields are not used while receiving. */
	sinfo.sinfo_timetolive = 0;

	put_cmsg(msghdr, IPPROTO_SCTP, SCTP_SNDRCV,
		 sizeof(struct sctp_sndrcvinfo), (void *)&sinfo);
}

/* Do accounting for bytes received and hold a reference to the association
 * for each skb.
 */
static void sctp_ulpevent_receive_data(struct sctp_ulpevent *event,
				       struct sctp_association *asoc)
{
	struct sk_buff *skb, *frag;

	skb = sctp_event2skb(event);
	/* Set the owner and charge rwnd for bytes received.  */
	sctp_ulpevent_set_owner(event, asoc);
992
	sctp_assoc_rwnd_decrease(asoc, skb_headlen(skb));
L
Linus Torvalds 已提交
993 994 995 996 997 998 999 1000

	if (!skb->data_len)
		return;

	/* Note:  Not clearing the entire event struct as this is just a
	 * fragment of the real event.  However, we still need to do rwnd
	 * accounting.
	 * In general, the skb passed from IP can have only 1 level of
1001
	 * fragments. But we allow multiple levels of fragments.
L
Linus Torvalds 已提交
1002
	 */
1003
	skb_walk_frags(skb, frag)
L
Linus Torvalds 已提交
1004 1005 1006 1007 1008
		sctp_ulpevent_receive_data(sctp_skb2event(frag), asoc);
}

/* Do accounting for bytes just read by user and release the references to
 * the association.
1009
 */
L
Linus Torvalds 已提交
1010 1011 1012
static void sctp_ulpevent_release_data(struct sctp_ulpevent *event)
{
	struct sk_buff *skb, *frag;
1013
	unsigned int	len;
L
Linus Torvalds 已提交
1014 1015 1016 1017 1018 1019 1020 1021 1022

	/* Current stack structures assume that the rcv buffer is
	 * per socket.   For UDP style sockets this is not true as
	 * multiple associations may be on a single UDP-style socket.
	 * Use the local private area of the skb to track the owning
	 * association.
	 */

	skb = sctp_event2skb(event);
1023 1024 1025 1026 1027 1028
	len = skb->len;

	if (!skb->data_len)
		goto done;

	/* Don't forget the fragments. */
1029
	skb_walk_frags(skb, frag) {
1030 1031 1032 1033 1034 1035 1036 1037
		/* NOTE:  skb_shinfos are recursive. Although IP returns
		 * skb's with only 1 level of fragments, SCTP reassembly can
		 * increase the levels.
		 */
		sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
	}

done:
1038
	sctp_assoc_rwnd_increase(event->asoc, len);
1039 1040 1041 1042 1043 1044 1045 1046
	sctp_ulpevent_release_owner(event);
}

static void sctp_ulpevent_release_frag_data(struct sctp_ulpevent *event)
{
	struct sk_buff *skb, *frag;

	skb = sctp_event2skb(event);
L
Linus Torvalds 已提交
1047 1048 1049 1050 1051

	if (!skb->data_len)
		goto done;

	/* Don't forget the fragments. */
1052
	skb_walk_frags(skb, frag) {
L
Linus Torvalds 已提交
1053 1054 1055 1056
		/* NOTE:  skb_shinfos are recursive. Although IP returns
		 * skb's with only 1 level of fragments, SCTP reassembly can
		 * increase the levels.
		 */
1057
		sctp_ulpevent_release_frag_data(sctp_skb2event(frag));
L
Linus Torvalds 已提交
1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078
	}

done:
	sctp_ulpevent_release_owner(event);
}

/* Free a ulpevent that has an owner.  It includes releasing the reference
 * to the owner, updating the rwnd in case of a DATA event and freeing the
 * skb.
 */
void sctp_ulpevent_free(struct sctp_ulpevent *event)
{
	if (sctp_ulpevent_is_notification(event))
		sctp_ulpevent_release_owner(event);
	else
		sctp_ulpevent_release_data(event);

	kfree_skb(sctp_event2skb(event));
}

/* Purge the skb lists holding ulpevents. */
1079
unsigned int sctp_queue_purge_ulpevents(struct sk_buff_head *list)
L
Linus Torvalds 已提交
1080 1081
{
	struct sk_buff *skb;
1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093
	unsigned int data_unread = 0;

	while ((skb = skb_dequeue(list)) != NULL) {
		struct sctp_ulpevent *event = sctp_skb2event(skb);

		if (!sctp_ulpevent_is_notification(event))
			data_unread += skb->len;

		sctp_ulpevent_free(event);
	}

	return data_unread;
L
Linus Torvalds 已提交
1094
}