1 /* SCTP kernel reference Implementation
2 * Copyright (c) 1999-2000 Cisco, Inc.
3 * Copyright (c) 1999-2001 Motorola, Inc.
4 * Copyright (c) 2001-2003 International Business Machines, Corp.
5 * Copyright (c) 2001 Intel Corp.
6 * Copyright (c) 2001 Nokia, Inc.
7 * Copyright (c) 2001 La Monte H.P. Yarroll
9 * This file is part of the SCTP kernel reference Implementation
11 * These functions handle all input from the IP layer into SCTP.
13 * The SCTP reference implementation is free software;
14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
19 * The SCTP reference implementation is distributed in the hope that it
20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA.
30 * Please send any bug reports or fixes you make to the
32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp
37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us>
40 * Xingang Guo <xingang.guo@intel.com>
41 * Jon Grimm <jgrimm@us.ibm.com>
42 * Hui Huang <hui.huang@nokia.com>
43 * Daisy Chang <daisyc@us.ibm.com>
44 * Sridhar Samudrala <sri@us.ibm.com>
45 * Ardelle Fan <ardelle.fan@intel.com>
47 * Any bugs reported given to us we will try to fix... any fixes shared will
48 * be incorporated into the next SCTP release.
51 #include <linux/types.h>
52 #include <linux/list.h> /* For struct list_head */
53 #include <linux/socket.h>
55 #include <linux/time.h> /* For struct timeval */
61 #include <net/sctp/sctp.h>
62 #include <net/sctp/sm.h>
64 /* Forward declarations for internal helpers. */
65 static int sctp_rcv_ootb(struct sk_buff *);
66 static struct sctp_association *__sctp_rcv_lookup(struct sk_buff *skb,
67 const union sctp_addr *laddr,
68 const union sctp_addr *paddr,
69 struct sctp_transport **transportp);
70 static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *laddr);
71 static struct sctp_association *__sctp_lookup_association(
72 const union sctp_addr *local,
73 const union sctp_addr *peer,
74 struct sctp_transport **pt);
77 /* Calculate the SCTP checksum of an SCTP packet. */
78 static inline int sctp_rcv_checksum(struct sk_buff *skb)
82 struct sk_buff *list = skb_shinfo(skb)->frag_list;
84 sh = (struct sctphdr *) skb->h.raw;
85 cmp = ntohl(sh->checksum);
87 val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb));
89 for (; list; list = list->next)
90 val = sctp_update_cksum((__u8 *)list->data, skb_headlen(list),
93 val = sctp_end_cksum(val);
96 /* CRC failure, dump it. */
97 SCTP_INC_STATS_BH(SCTP_MIB_CHECKSUMERRORS);
103 /* The free routine for skbuffs that sctp receives */
104 static void sctp_rfree(struct sk_buff *skb)
106 atomic_sub(sizeof(struct sctp_chunk),&skb->sk->sk_rmem_alloc);
110 /* The ownership wrapper routine to do receive buffer accounting */
111 static void sctp_rcv_set_owner_r(struct sk_buff *skb, struct sock *sk)
113 skb_set_owner_r(skb,sk);
114 skb->destructor = sctp_rfree;
115 atomic_add(sizeof(struct sctp_chunk),&sk->sk_rmem_alloc);
119 * This is the routine which IP calls when receiving an SCTP packet.
121 int sctp_rcv(struct sk_buff *skb)
124 struct sctp_association *asoc;
125 struct sctp_endpoint *ep = NULL;
126 struct sctp_ep_common *rcvr;
127 struct sctp_transport *transport = NULL;
128 struct sctp_chunk *chunk;
131 union sctp_addr dest;
136 if (skb->pkt_type!=PACKET_HOST)
139 SCTP_INC_STATS_BH(SCTP_MIB_INSCTPPACKS);
141 sh = (struct sctphdr *) skb->h.raw;
143 /* Pull up the IP and SCTP headers. */
144 __skb_pull(skb, skb->h.raw - skb->data);
145 if (skb->len < sizeof(struct sctphdr))
147 if (sctp_rcv_checksum(skb) < 0)
150 skb_pull(skb, sizeof(struct sctphdr));
152 /* Make sure we at least have chunk headers worth of data left. */
153 if (skb->len < sizeof(struct sctp_chunkhdr))
156 family = ipver2af(skb->nh.iph->version);
157 af = sctp_get_af_specific(family);
161 /* Initialize local addresses for lookups. */
162 af->from_skb(&src, skb, 1);
163 af->from_skb(&dest, skb, 0);
165 /* If the packet is to or from a non-unicast address,
166 * silently discard the packet.
168 * This is not clearly defined in the RFC except in section
169 * 8.4 - OOTB handling. However, based on the book "Stream Control
170 * Transmission Protocol" 2.1, "It is important to note that the
171 * IP address of an SCTP transport address must be a routable
172 * unicast address. In other words, IP multicast addresses and
173 * IP broadcast addresses cannot be used in an SCTP transport
176 if (!af->addr_valid(&src, NULL) || !af->addr_valid(&dest, NULL))
179 asoc = __sctp_rcv_lookup(skb, &src, &dest, &transport);
182 * RFC 2960, 8.4 - Handle "Out of the blue" Packets.
183 * An SCTP packet is called an "out of the blue" (OOTB)
184 * packet if it is correctly formed, i.e., passed the
185 * receiver's checksum check, but the receiver is not
186 * able to identify the association to which this
190 ep = __sctp_rcv_lookup_endpoint(&dest);
191 if (sctp_rcv_ootb(skb)) {
192 SCTP_INC_STATS_BH(SCTP_MIB_OUTOFBLUES);
193 goto discard_release;
197 /* Retrieve the common input handling substructure. */
198 rcvr = asoc ? &asoc->base : &ep->base;
201 if ((sk) && (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)) {
202 goto discard_release;
206 /* SCTP seems to always need a timestamp right now (FIXME) */
207 if (skb->stamp.tv_sec == 0) {
208 do_gettimeofday(&skb->stamp);
209 sock_enable_timestamp(sk);
212 if (!xfrm_policy_check(sk, XFRM_POLICY_IN, skb, family))
213 goto discard_release;
215 ret = sk_filter(sk, skb, 1);
217 goto discard_release;
219 /* Create an SCTP packet structure. */
220 chunk = sctp_chunkify(skb, asoc, sk);
223 goto discard_release;
226 sctp_rcv_set_owner_r(skb,sk);
228 /* Remember what endpoint is to handle this packet. */
231 /* Remember the SCTP header. */
232 chunk->sctp_hdr = sh;
234 /* Set the source and destination addresses of the incoming chunk. */
235 sctp_init_addrs(chunk, &src, &dest);
237 /* Remember where we came from. */
238 chunk->transport = transport;
240 /* Acquire access to the sock lock. Note: We are safe from other
241 * bottom halves on this lock, but a user may be in the lock too,
242 * so check if it is busy.
244 sctp_bh_lock_sock(sk);
246 if (sock_owned_by_user(sk))
247 sk_add_backlog(sk, (struct sk_buff *) chunk);
249 sctp_backlog_rcv(sk, (struct sk_buff *) chunk);
251 /* Release the sock and any reference counts we took in the
254 sctp_bh_unlock_sock(sk);
256 sctp_association_put(asoc);
258 sctp_endpoint_put(ep);
267 /* Release any structures we may be holding. */
269 sock_put(asoc->base.sk);
270 sctp_association_put(asoc);
272 sock_put(ep->base.sk);
273 sctp_endpoint_put(ep);
279 /* Handle second half of inbound skb processing. If the sock was busy,
280 * we may have need to delay processing until later when the sock is
281 * released (on the backlog). If not busy, we call this routine
282 * directly from the bottom half.
284 int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb)
286 struct sctp_chunk *chunk;
287 struct sctp_inq *inqueue;
289 /* One day chunk will live inside the skb, but for
292 chunk = (struct sctp_chunk *) skb;
293 inqueue = &chunk->rcvr->inqueue;
295 sctp_inq_push(inqueue, chunk);
299 /* Handle icmp frag needed error. */
300 void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc,
301 struct sctp_transport *t, __u32 pmtu)
303 if (unlikely(pmtu < SCTP_DEFAULT_MINSEGMENT)) {
304 printk(KERN_WARNING "%s: Reported pmtu %d too low, "
305 "using default minimum of %d\n", __FUNCTION__, pmtu,
306 SCTP_DEFAULT_MINSEGMENT);
307 pmtu = SCTP_DEFAULT_MINSEGMENT;
310 if (!sock_owned_by_user(sk) && t && (t->pmtu != pmtu)) {
312 sctp_assoc_sync_pmtu(asoc);
313 sctp_retransmit(&asoc->outqueue, t, SCTP_RTXR_PMTUD);
318 * SCTP Implementer's Guide, 2.37 ICMP handling procedures
320 * ICMP8) If the ICMP code is a "Unrecognized next header type encountered"
321 * or a "Protocol Unreachable" treat this message as an abort
322 * with the T bit set.
324 * This function sends an event to the state machine, which will abort the
328 void sctp_icmp_proto_unreachable(struct sock *sk,
329 struct sctp_endpoint *ep,
330 struct sctp_association *asoc,
331 struct sctp_transport *t)
333 SCTP_DEBUG_PRINTK("%s\n", __FUNCTION__);
335 sctp_do_sm(SCTP_EVENT_T_OTHER,
336 SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
337 asoc->state, asoc->ep, asoc, NULL,
342 /* Common lookup code for icmp/icmpv6 error handler. */
343 struct sock *sctp_err_lookup(int family, struct sk_buff *skb,
344 struct sctphdr *sctphdr,
345 struct sctp_endpoint **epp,
346 struct sctp_association **app,
347 struct sctp_transport **tpp)
349 union sctp_addr saddr;
350 union sctp_addr daddr;
352 struct sock *sk = NULL;
353 struct sctp_endpoint *ep = NULL;
354 struct sctp_association *asoc = NULL;
355 struct sctp_transport *transport = NULL;
357 *app = NULL; *epp = NULL; *tpp = NULL;
359 af = sctp_get_af_specific(family);
364 /* Initialize local addresses for lookups. */
365 af->from_skb(&saddr, skb, 1);
366 af->from_skb(&daddr, skb, 0);
368 /* Look for an association that matches the incoming ICMP error
371 asoc = __sctp_lookup_association(&saddr, &daddr, &transport);
373 /* If there is no matching association, see if it matches any
374 * endpoint. This may happen for an ICMP error generated in
375 * response to an INIT_ACK.
377 ep = __sctp_rcv_lookup_endpoint(&daddr);
386 if (ntohl(sctphdr->vtag) != asoc->c.peer_vtag) {
387 ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
393 sctp_bh_lock_sock(sk);
395 /* If too many ICMPs get dropped on busy
396 * servers this needs to be solved differently.
398 if (sock_owned_by_user(sk))
399 NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);
409 sctp_association_put(asoc);
411 sctp_endpoint_put(ep);
415 /* Common cleanup code for icmp/icmpv6 error handler. */
416 void sctp_err_finish(struct sock *sk, struct sctp_endpoint *ep,
417 struct sctp_association *asoc)
419 sctp_bh_unlock_sock(sk);
422 sctp_association_put(asoc);
424 sctp_endpoint_put(ep);
428 * This routine is called by the ICMP module when it gets some
429 * sort of error condition. If err < 0 then the socket should
430 * be closed and the error returned to the user. If err > 0
431 * it's just the icmp type << 8 | icmp code. After adjustment
432 * header points to the first 8 bytes of the sctp header. We need
433 * to find the appropriate port.
435 * The locking strategy used here is very "optimistic". When
436 * someone else accesses the socket the ICMP is just dropped
437 * and for some paths there is no check at all.
438 * A more general error queue to queue errors for later handling
439 * is probably better.
442 void sctp_v4_err(struct sk_buff *skb, __u32 info)
444 struct iphdr *iph = (struct iphdr *)skb->data;
445 struct sctphdr *sh = (struct sctphdr *)(skb->data + (iph->ihl <<2));
446 int type = skb->h.icmph->type;
447 int code = skb->h.icmph->code;
449 struct sctp_endpoint *ep;
450 struct sctp_association *asoc;
451 struct sctp_transport *transport;
452 struct inet_sock *inet;
453 char *saveip, *savesctp;
456 if (skb->len < ((iph->ihl << 2) + 8)) {
457 ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
461 /* Fix up skb to look at the embedded net header. */
462 saveip = skb->nh.raw;
463 savesctp = skb->h.raw;
465 skb->h.raw = (char *)sh;
466 sk = sctp_err_lookup(AF_INET, skb, sh, &ep, &asoc, &transport);
467 /* Put back, the original pointers. */
468 skb->nh.raw = saveip;
469 skb->h.raw = savesctp;
471 ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
474 /* Warning: The sock lock is held. Remember to call
479 case ICMP_PARAMETERPROB:
482 case ICMP_DEST_UNREACH:
483 if (code > NR_ICMP_UNREACH)
486 /* PMTU discovery (RFC1191) */
487 if (ICMP_FRAG_NEEDED == code) {
488 sctp_icmp_frag_needed(sk, asoc, transport, info);
492 if (ICMP_PROT_UNREACH == code) {
493 sctp_icmp_proto_unreachable(sk, ep, asoc,
498 err = icmp_err_convert[code].errno;
500 case ICMP_TIME_EXCEEDED:
501 /* Ignore any time exceeded errors due to fragment reassembly
504 if (ICMP_EXC_FRAGTIME == code)
514 if (!sock_owned_by_user(sk) && inet->recverr) {
516 sk->sk_error_report(sk);
517 } else { /* Only an error on timeout */
518 sk->sk_err_soft = err;
522 sctp_err_finish(sk, ep, asoc);
526 * RFC 2960, 8.4 - Handle "Out of the blue" Packets.
528 * This function scans all the chunks in the OOTB packet to determine if
529 * the packet should be discarded right away. If a response might be needed
530 * for this packet, or, if further processing is possible, the packet will
531 * be queued to a proper inqueue for the next phase of handling.
534 * Return 0 - If further processing is needed.
535 * Return 1 - If the packet can be discarded right away.
537 int sctp_rcv_ootb(struct sk_buff *skb)
543 ch = (sctp_chunkhdr_t *) skb->data;
544 ch_end = ((__u8 *) ch) + WORD_ROUND(ntohs(ch->length));
546 /* Scan through all the chunks in the packet. */
547 while (ch_end > (__u8 *)ch && ch_end < skb->tail) {
549 /* RFC 8.4, 2) If the OOTB packet contains an ABORT chunk, the
550 * receiver MUST silently discard the OOTB packet and take no
553 if (SCTP_CID_ABORT == ch->type)
556 /* RFC 8.4, 6) If the packet contains a SHUTDOWN COMPLETE
557 * chunk, the receiver should silently discard the packet
558 * and take no further action.
560 if (SCTP_CID_SHUTDOWN_COMPLETE == ch->type)
563 /* RFC 8.4, 7) If the packet contains a "Stale cookie" ERROR
564 * or a COOKIE ACK the SCTP Packet should be silently
567 if (SCTP_CID_COOKIE_ACK == ch->type)
570 if (SCTP_CID_ERROR == ch->type) {
571 sctp_walk_errors(err, ch) {
572 if (SCTP_ERROR_STALE_COOKIE == err->cause)
577 ch = (sctp_chunkhdr_t *) ch_end;
578 ch_end = ((__u8 *) ch) + WORD_ROUND(ntohs(ch->length));
587 /* Insert endpoint into the hash table. */
588 static void __sctp_hash_endpoint(struct sctp_endpoint *ep)
590 struct sctp_ep_common **epp;
591 struct sctp_ep_common *epb;
592 struct sctp_hashbucket *head;
596 epb->hashent = sctp_ep_hashfn(epb->bind_addr.port);
597 head = &sctp_ep_hashtable[epb->hashent];
599 sctp_write_lock(&head->lock);
603 (*epp)->pprev = &epb->next;
606 sctp_write_unlock(&head->lock);
609 /* Add an endpoint to the hash. Local BH-safe. */
610 void sctp_hash_endpoint(struct sctp_endpoint *ep)
612 sctp_local_bh_disable();
613 __sctp_hash_endpoint(ep);
614 sctp_local_bh_enable();
617 /* Remove endpoint from the hash table. */
618 static void __sctp_unhash_endpoint(struct sctp_endpoint *ep)
620 struct sctp_hashbucket *head;
621 struct sctp_ep_common *epb;
625 epb->hashent = sctp_ep_hashfn(epb->bind_addr.port);
627 head = &sctp_ep_hashtable[epb->hashent];
629 sctp_write_lock(&head->lock);
633 epb->next->pprev = epb->pprev;
634 *epb->pprev = epb->next;
638 sctp_write_unlock(&head->lock);
641 /* Remove endpoint from the hash. Local BH-safe. */
642 void sctp_unhash_endpoint(struct sctp_endpoint *ep)
644 sctp_local_bh_disable();
645 __sctp_unhash_endpoint(ep);
646 sctp_local_bh_enable();
649 /* Look up an endpoint. */
650 static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *laddr)
652 struct sctp_hashbucket *head;
653 struct sctp_ep_common *epb;
654 struct sctp_endpoint *ep;
657 hash = sctp_ep_hashfn(laddr->v4.sin_port);
658 head = &sctp_ep_hashtable[hash];
659 read_lock(&head->lock);
660 for (epb = head->chain; epb; epb = epb->next) {
662 if (sctp_endpoint_is_match(ep, laddr))
666 ep = sctp_sk((sctp_get_ctl_sock()))->ep;
670 sctp_endpoint_hold(ep);
672 read_unlock(&head->lock);
676 /* Insert association into the hash table. */
677 static void __sctp_hash_established(struct sctp_association *asoc)
679 struct sctp_ep_common **epp;
680 struct sctp_ep_common *epb;
681 struct sctp_hashbucket *head;
685 /* Calculate which chain this entry will belong to. */
686 epb->hashent = sctp_assoc_hashfn(epb->bind_addr.port, asoc->peer.port);
688 head = &sctp_assoc_hashtable[epb->hashent];
690 sctp_write_lock(&head->lock);
694 (*epp)->pprev = &epb->next;
697 sctp_write_unlock(&head->lock);
700 /* Add an association to the hash. Local BH-safe. */
701 void sctp_hash_established(struct sctp_association *asoc)
703 sctp_local_bh_disable();
704 __sctp_hash_established(asoc);
705 sctp_local_bh_enable();
708 /* Remove association from the hash table. */
709 static void __sctp_unhash_established(struct sctp_association *asoc)
711 struct sctp_hashbucket *head;
712 struct sctp_ep_common *epb;
716 epb->hashent = sctp_assoc_hashfn(epb->bind_addr.port,
719 head = &sctp_assoc_hashtable[epb->hashent];
721 sctp_write_lock(&head->lock);
725 epb->next->pprev = epb->pprev;
726 *epb->pprev = epb->next;
730 sctp_write_unlock(&head->lock);
733 /* Remove association from the hash table. Local BH-safe. */
734 void sctp_unhash_established(struct sctp_association *asoc)
736 sctp_local_bh_disable();
737 __sctp_unhash_established(asoc);
738 sctp_local_bh_enable();
741 /* Look up an association. */
742 static struct sctp_association *__sctp_lookup_association(
743 const union sctp_addr *local,
744 const union sctp_addr *peer,
745 struct sctp_transport **pt)
747 struct sctp_hashbucket *head;
748 struct sctp_ep_common *epb;
749 struct sctp_association *asoc;
750 struct sctp_transport *transport;
753 /* Optimize here for direct hit, only listening connections can
754 * have wildcards anyways.
756 hash = sctp_assoc_hashfn(local->v4.sin_port, peer->v4.sin_port);
757 head = &sctp_assoc_hashtable[hash];
758 read_lock(&head->lock);
759 for (epb = head->chain; epb; epb = epb->next) {
760 asoc = sctp_assoc(epb);
761 transport = sctp_assoc_is_match(asoc, local, peer);
766 read_unlock(&head->lock);
772 sctp_association_hold(asoc);
774 read_unlock(&head->lock);
778 /* Look up an association. BH-safe. */
780 struct sctp_association *sctp_lookup_association(const union sctp_addr *laddr,
781 const union sctp_addr *paddr,
782 struct sctp_transport **transportp)
784 struct sctp_association *asoc;
786 sctp_local_bh_disable();
787 asoc = __sctp_lookup_association(laddr, paddr, transportp);
788 sctp_local_bh_enable();
793 /* Is there an association matching the given local and peer addresses? */
794 int sctp_has_association(const union sctp_addr *laddr,
795 const union sctp_addr *paddr)
797 struct sctp_association *asoc;
798 struct sctp_transport *transport;
800 if ((asoc = sctp_lookup_association(laddr, paddr, &transport))) {
801 sock_put(asoc->base.sk);
802 sctp_association_put(asoc);
810 * SCTP Implementors Guide, 2.18 Handling of address
811 * parameters within the INIT or INIT-ACK.
813 * D) When searching for a matching TCB upon reception of an INIT
814 * or INIT-ACK chunk the receiver SHOULD use not only the
815 * source address of the packet (containing the INIT or
816 * INIT-ACK) but the receiver SHOULD also use all valid
817 * address parameters contained within the chunk.
819 * 2.18.3 Solution description
821 * This new text clearly specifies to an implementor the need
822 * to look within the INIT or INIT-ACK. Any implementation that
823 * does not do this, may not be able to establish associations
824 * in certain circumstances.
827 static struct sctp_association *__sctp_rcv_init_lookup(struct sk_buff *skb,
828 const union sctp_addr *laddr, struct sctp_transport **transportp)
830 struct sctp_association *asoc;
831 union sctp_addr addr;
832 union sctp_addr *paddr = &addr;
833 struct sctphdr *sh = (struct sctphdr *) skb->h.raw;
835 union sctp_params params;
836 sctp_init_chunk_t *init;
837 struct sctp_transport *transport;
840 ch = (sctp_chunkhdr_t *) skb->data;
842 /* If this is INIT/INIT-ACK look inside the chunk too. */
845 case SCTP_CID_INIT_ACK:
851 /* The code below will attempt to walk the chunk and extract
852 * parameter information. Before we do that, we need to verify
853 * that the chunk length doesn't cause overflow. Otherwise, we'll
856 if (WORD_ROUND(ntohs(ch->length)) > skb->len)
860 * This code will NOT touch anything inside the chunk--it is
861 * strictly READ-ONLY.
863 * RFC 2960 3 SCTP packet Format
865 * Multiple chunks can be bundled into one SCTP packet up to
866 * the MTU size, except for the INIT, INIT ACK, and SHUTDOWN
867 * COMPLETE chunks. These chunks MUST NOT be bundled with any
868 * other chunk in a packet. See Section 6.10 for more details
872 /* Find the start of the TLVs and the end of the chunk. This is
873 * the region we search for address parameters.
875 init = (sctp_init_chunk_t *)skb->data;
877 /* Walk the parameters looking for embedded addresses. */
878 sctp_walk_params(params, init, init_hdr.params) {
880 /* Note: Ignoring hostname addresses. */
881 af = sctp_get_af_specific(param_type2af(params.p->type));
885 af->from_addr_param(paddr, params.addr, ntohs(sh->source), 0);
887 asoc = __sctp_lookup_association(laddr, paddr, &transport);
895 /* Lookup an association for an inbound skb. */
896 static struct sctp_association *__sctp_rcv_lookup(struct sk_buff *skb,
897 const union sctp_addr *paddr,
898 const union sctp_addr *laddr,
899 struct sctp_transport **transportp)
901 struct sctp_association *asoc;
903 asoc = __sctp_lookup_association(laddr, paddr, transportp);
905 /* Further lookup for INIT/INIT-ACK packets.
906 * SCTP Implementors Guide, 2.18 Handling of address
907 * parameters within the INIT or INIT-ACK.
910 asoc = __sctp_rcv_init_lookup(skb, laddr, transportp);