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