Vlad Yasevich | 60c778b | 2008-01-11 09:57:09 -0500 | [diff] [blame] | 1 | /* SCTP kernel implementation |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 |
| 8 | * |
Vlad Yasevich | 60c778b | 2008-01-11 09:57:09 -0500 | [diff] [blame] | 9 | * This file is part of the SCTP kernel implementation |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | * |
| 11 | * These functions handle all input from the IP layer into SCTP. |
| 12 | * |
Vlad Yasevich | 60c778b | 2008-01-11 09:57:09 -0500 | [diff] [blame] | 13 | * This SCTP implementation is free software; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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) |
| 17 | * any later version. |
| 18 | * |
Vlad Yasevich | 60c778b | 2008-01-11 09:57:09 -0500 | [diff] [blame] | 19 | * This SCTP implementation is distributed in the hope that it |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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. |
| 24 | * |
| 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. |
| 29 | * |
| 30 | * Please send any bug reports or fixes you make to the |
| 31 | * email address(es): |
| 32 | * lksctp developers <lksctp-developers@lists.sourceforge.net> |
| 33 | * |
| 34 | * Or submit a bug report through the following website: |
| 35 | * http://www.sf.net/projects/lksctp |
| 36 | * |
| 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> |
| 46 | * |
| 47 | * Any bugs reported given to us we will try to fix... any fixes shared will |
| 48 | * be incorporated into the next SCTP release. |
| 49 | */ |
| 50 | |
| 51 | #include <linux/types.h> |
| 52 | #include <linux/list.h> /* For struct list_head */ |
| 53 | #include <linux/socket.h> |
| 54 | #include <linux/ip.h> |
| 55 | #include <linux/time.h> /* For struct timeval */ |
| 56 | #include <net/ip.h> |
| 57 | #include <net/icmp.h> |
| 58 | #include <net/snmp.h> |
| 59 | #include <net/sock.h> |
| 60 | #include <net/xfrm.h> |
| 61 | #include <net/sctp/sctp.h> |
| 62 | #include <net/sctp/sm.h> |
Vlad Yasevich | 9ad0977 | 2007-12-16 14:06:41 -0800 | [diff] [blame] | 63 | #include <net/sctp/checksum.h> |
Pavel Emelyanov | dcfc23c | 2008-07-14 23:03:00 -0700 | [diff] [blame] | 64 | #include <net/net_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | |
| 66 | /* Forward declarations for internal helpers. */ |
| 67 | static int sctp_rcv_ootb(struct sk_buff *); |
| 68 | static struct sctp_association *__sctp_rcv_lookup(struct sk_buff *skb, |
| 69 | const union sctp_addr *laddr, |
| 70 | const union sctp_addr *paddr, |
| 71 | struct sctp_transport **transportp); |
| 72 | static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *laddr); |
| 73 | static struct sctp_association *__sctp_lookup_association( |
| 74 | const union sctp_addr *local, |
| 75 | const union sctp_addr *peer, |
| 76 | struct sctp_transport **pt); |
| 77 | |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 78 | static void sctp_add_backlog(struct sock *sk, struct sk_buff *skb); |
| 79 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | |
| 81 | /* Calculate the SCTP checksum of an SCTP packet. */ |
| 82 | static inline int sctp_rcv_checksum(struct sk_buff *skb) |
| 83 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | struct sk_buff *list = skb_shinfo(skb)->frag_list; |
Arnaldo Carvalho de Melo | 2c0fd38 | 2007-03-13 13:59:32 -0300 | [diff] [blame] | 85 | struct sctphdr *sh = sctp_hdr(skb); |
Vlad Yasevich | 4458f04 | 2009-02-13 08:33:42 +0000 | [diff] [blame] | 86 | __le32 cmp = sh->checksum; |
| 87 | __le32 val; |
| 88 | __u32 tmp = sctp_start_cksum((__u8 *)sh, skb_headlen(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | |
| 90 | for (; list; list = list->next) |
Vlad Yasevich | 4458f04 | 2009-02-13 08:33:42 +0000 | [diff] [blame] | 91 | tmp = sctp_update_cksum((__u8 *)list->data, skb_headlen(list), |
| 92 | tmp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | |
Vlad Yasevich | 4458f04 | 2009-02-13 08:33:42 +0000 | [diff] [blame] | 94 | val = sctp_end_cksum(tmp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 95 | |
| 96 | if (val != cmp) { |
| 97 | /* CRC failure, dump it. */ |
| 98 | SCTP_INC_STATS_BH(SCTP_MIB_CHECKSUMERRORS); |
| 99 | return -1; |
| 100 | } |
| 101 | return 0; |
| 102 | } |
| 103 | |
David S. Miller | 79af02c | 2005-07-08 21:47:49 -0700 | [diff] [blame] | 104 | struct sctp_input_cb { |
| 105 | union { |
| 106 | struct inet_skb_parm h4; |
| 107 | #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) |
| 108 | struct inet6_skb_parm h6; |
| 109 | #endif |
| 110 | } header; |
| 111 | struct sctp_chunk *chunk; |
| 112 | }; |
| 113 | #define SCTP_INPUT_CB(__skb) ((struct sctp_input_cb *)&((__skb)->cb[0])) |
| 114 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 115 | /* |
| 116 | * This is the routine which IP calls when receiving an SCTP packet. |
| 117 | */ |
| 118 | int sctp_rcv(struct sk_buff *skb) |
| 119 | { |
| 120 | struct sock *sk; |
| 121 | struct sctp_association *asoc; |
| 122 | struct sctp_endpoint *ep = NULL; |
| 123 | struct sctp_ep_common *rcvr; |
| 124 | struct sctp_transport *transport = NULL; |
| 125 | struct sctp_chunk *chunk; |
| 126 | struct sctphdr *sh; |
| 127 | union sctp_addr src; |
| 128 | union sctp_addr dest; |
| 129 | int family; |
| 130 | struct sctp_af *af; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | |
| 132 | if (skb->pkt_type!=PACKET_HOST) |
| 133 | goto discard_it; |
| 134 | |
| 135 | SCTP_INC_STATS_BH(SCTP_MIB_INSCTPPACKS); |
| 136 | |
Herbert Xu | 28cd775 | 2006-10-29 23:46:42 -0800 | [diff] [blame] | 137 | if (skb_linearize(skb)) |
| 138 | goto discard_it; |
| 139 | |
Arnaldo Carvalho de Melo | 2c0fd38 | 2007-03-13 13:59:32 -0300 | [diff] [blame] | 140 | sh = sctp_hdr(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | |
| 142 | /* Pull up the IP and SCTP headers. */ |
Arnaldo Carvalho de Melo | ea2ae17 | 2007-04-25 17:55:53 -0700 | [diff] [blame] | 143 | __skb_pull(skb, skb_transport_offset(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | if (skb->len < sizeof(struct sctphdr)) |
| 145 | goto discard_it; |
Lucas Nussbaum | 06e8680 | 2009-02-13 08:33:41 +0000 | [diff] [blame] | 146 | if (!sctp_checksum_disable && !skb_csum_unnecessary(skb) && |
| 147 | sctp_rcv_checksum(skb) < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | goto discard_it; |
| 149 | |
| 150 | skb_pull(skb, sizeof(struct sctphdr)); |
| 151 | |
| 152 | /* Make sure we at least have chunk headers worth of data left. */ |
| 153 | if (skb->len < sizeof(struct sctp_chunkhdr)) |
| 154 | goto discard_it; |
| 155 | |
Arnaldo Carvalho de Melo | eddc9ec | 2007-04-20 22:47:35 -0700 | [diff] [blame] | 156 | family = ipver2af(ip_hdr(skb)->version); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | af = sctp_get_af_specific(family); |
| 158 | if (unlikely(!af)) |
| 159 | goto discard_it; |
| 160 | |
| 161 | /* Initialize local addresses for lookups. */ |
| 162 | af->from_skb(&src, skb, 1); |
| 163 | af->from_skb(&dest, skb, 0); |
| 164 | |
| 165 | /* If the packet is to or from a non-unicast address, |
| 166 | * silently discard the packet. |
| 167 | * |
| 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 |
| 174 | * address." |
| 175 | */ |
Vlad Yasevich | 5636bef | 2006-06-17 22:55:35 -0700 | [diff] [blame] | 176 | if (!af->addr_valid(&src, NULL, skb) || |
| 177 | !af->addr_valid(&dest, NULL, skb)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | goto discard_it; |
| 179 | |
Al Viro | d55c41b | 2006-11-20 17:09:40 -0800 | [diff] [blame] | 180 | asoc = __sctp_rcv_lookup(skb, &src, &dest, &transport); |
Al Viro | 1c7d1fc | 2006-11-20 17:08:09 -0800 | [diff] [blame] | 181 | |
Neil Horman | 0fd9a65 | 2005-06-13 15:11:24 -0700 | [diff] [blame] | 182 | if (!asoc) |
Al Viro | d55c41b | 2006-11-20 17:09:40 -0800 | [diff] [blame] | 183 | ep = __sctp_rcv_lookup_endpoint(&dest); |
Neil Horman | 0fd9a65 | 2005-06-13 15:11:24 -0700 | [diff] [blame] | 184 | |
| 185 | /* Retrieve the common input handling substructure. */ |
| 186 | rcvr = asoc ? &asoc->base : &ep->base; |
| 187 | sk = rcvr->sk; |
| 188 | |
| 189 | /* |
| 190 | * If a frame arrives on an interface and the receiving socket is |
| 191 | * bound to another interface, via SO_BINDTODEVICE, treat it as OOTB |
| 192 | */ |
| 193 | if (sk->sk_bound_dev_if && (sk->sk_bound_dev_if != af->skb_iif(skb))) |
| 194 | { |
Neil Horman | 0fd9a65 | 2005-06-13 15:11:24 -0700 | [diff] [blame] | 195 | if (asoc) { |
| 196 | sctp_association_put(asoc); |
| 197 | asoc = NULL; |
| 198 | } else { |
| 199 | sctp_endpoint_put(ep); |
| 200 | ep = NULL; |
| 201 | } |
| 202 | sk = sctp_get_ctl_sock(); |
| 203 | ep = sctp_sk(sk)->ep; |
| 204 | sctp_endpoint_hold(ep); |
Neil Horman | 0fd9a65 | 2005-06-13 15:11:24 -0700 | [diff] [blame] | 205 | rcvr = &ep->base; |
| 206 | } |
| 207 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | /* |
| 209 | * RFC 2960, 8.4 - Handle "Out of the blue" Packets. |
| 210 | * An SCTP packet is called an "out of the blue" (OOTB) |
| 211 | * packet if it is correctly formed, i.e., passed the |
| 212 | * receiver's checksum check, but the receiver is not |
| 213 | * able to identify the association to which this |
| 214 | * packet belongs. |
| 215 | */ |
| 216 | if (!asoc) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 217 | if (sctp_rcv_ootb(skb)) { |
| 218 | SCTP_INC_STATS_BH(SCTP_MIB_OUTOFBLUES); |
| 219 | goto discard_release; |
| 220 | } |
| 221 | } |
| 222 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | if (!xfrm_policy_check(sk, XFRM_POLICY_IN, skb, family)) |
| 224 | goto discard_release; |
Patrick McHardy | b59c270 | 2006-01-06 23:06:10 -0800 | [diff] [blame] | 225 | nf_reset(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | |
Dmitry Mishin | fda9ef5 | 2006-08-31 15:28:39 -0700 | [diff] [blame] | 227 | if (sk_filter(sk, skb)) |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 228 | goto discard_release; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | |
| 230 | /* Create an SCTP packet structure. */ |
| 231 | chunk = sctp_chunkify(skb, asoc, sk); |
Herbert Xu | 2babf9d | 2006-03-25 01:25:29 -0800 | [diff] [blame] | 232 | if (!chunk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | goto discard_release; |
David S. Miller | 79af02c | 2005-07-08 21:47:49 -0700 | [diff] [blame] | 234 | SCTP_INPUT_CB(skb)->chunk = chunk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | /* Remember what endpoint is to handle this packet. */ |
| 237 | chunk->rcvr = rcvr; |
| 238 | |
| 239 | /* Remember the SCTP header. */ |
| 240 | chunk->sctp_hdr = sh; |
| 241 | |
| 242 | /* Set the source and destination addresses of the incoming chunk. */ |
Al Viro | d55c41b | 2006-11-20 17:09:40 -0800 | [diff] [blame] | 243 | sctp_init_addrs(chunk, &src, &dest); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | |
| 245 | /* Remember where we came from. */ |
| 246 | chunk->transport = transport; |
| 247 | |
| 248 | /* Acquire access to the sock lock. Note: We are safe from other |
| 249 | * bottom halves on this lock, but a user may be in the lock too, |
| 250 | * so check if it is busy. |
| 251 | */ |
| 252 | sctp_bh_lock_sock(sk); |
| 253 | |
Vlad Yasevich | ae53b5b | 2009-01-22 14:53:23 -0800 | [diff] [blame] | 254 | if (sk != rcvr->sk) { |
| 255 | /* Our cached sk is different from the rcvr->sk. This is |
| 256 | * because migrate()/accept() may have moved the association |
| 257 | * to a new socket and released all the sockets. So now we |
| 258 | * are holding a lock on the old socket while the user may |
| 259 | * be doing something with the new socket. Switch our veiw |
| 260 | * of the current sk. |
| 261 | */ |
| 262 | sctp_bh_unlock_sock(sk); |
| 263 | sk = rcvr->sk; |
| 264 | sctp_bh_lock_sock(sk); |
| 265 | } |
| 266 | |
Sridhar Samudrala | ac0b046 | 2006-08-22 00:15:33 -0700 | [diff] [blame] | 267 | if (sock_owned_by_user(sk)) { |
| 268 | SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_BACKLOG); |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 269 | sctp_add_backlog(sk, skb); |
Sridhar Samudrala | ac0b046 | 2006-08-22 00:15:33 -0700 | [diff] [blame] | 270 | } else { |
| 271 | SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_SOFTIRQ); |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 272 | sctp_inq_push(&chunk->rcvr->inqueue, chunk); |
Sridhar Samudrala | ac0b046 | 2006-08-22 00:15:33 -0700 | [diff] [blame] | 273 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | sctp_bh_unlock_sock(sk); |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 276 | |
| 277 | /* Release the asoc/ep ref we took in the lookup calls. */ |
| 278 | if (asoc) |
| 279 | sctp_association_put(asoc); |
| 280 | else |
| 281 | sctp_endpoint_put(ep); |
Sridhar Samudrala | 7a48f92 | 2006-01-17 11:51:28 -0800 | [diff] [blame] | 282 | |
Herbert Xu | 2babf9d | 2006-03-25 01:25:29 -0800 | [diff] [blame] | 283 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | |
| 285 | discard_it: |
Sridhar Samudrala | ac0b046 | 2006-08-22 00:15:33 -0700 | [diff] [blame] | 286 | SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_DISCARDS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 287 | kfree_skb(skb); |
Herbert Xu | 2babf9d | 2006-03-25 01:25:29 -0800 | [diff] [blame] | 288 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | |
| 290 | discard_release: |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 291 | /* Release the asoc/ep ref we took in the lookup calls. */ |
Neil Horman | 0fd9a65 | 2005-06-13 15:11:24 -0700 | [diff] [blame] | 292 | if (asoc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 293 | sctp_association_put(asoc); |
Neil Horman | 0fd9a65 | 2005-06-13 15:11:24 -0700 | [diff] [blame] | 294 | else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 295 | sctp_endpoint_put(ep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | |
| 297 | goto discard_it; |
| 298 | } |
| 299 | |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 300 | /* Process the backlog queue of the socket. Every skb on |
| 301 | * the backlog holds a ref on an association or endpoint. |
| 302 | * We hold this ref throughout the state machine to make |
| 303 | * sure that the structure we need is still around. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | */ |
| 305 | int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb) |
| 306 | { |
David S. Miller | 79af02c | 2005-07-08 21:47:49 -0700 | [diff] [blame] | 307 | struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 308 | struct sctp_inq *inqueue = &chunk->rcvr->inqueue; |
| 309 | struct sctp_ep_common *rcvr = NULL; |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 310 | int backloged = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 312 | rcvr = chunk->rcvr; |
Sridhar Samudrala | c4d2444 | 2006-01-17 11:56:26 -0800 | [diff] [blame] | 313 | |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 314 | /* If the rcvr is dead then the association or endpoint |
| 315 | * has been deleted and we can safely drop the chunk |
| 316 | * and refs that we are holding. |
| 317 | */ |
| 318 | if (rcvr->dead) { |
| 319 | sctp_chunk_free(chunk); |
| 320 | goto done; |
| 321 | } |
Sridhar Samudrala | c4d2444 | 2006-01-17 11:56:26 -0800 | [diff] [blame] | 322 | |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 323 | if (unlikely(rcvr->sk != sk)) { |
| 324 | /* In this case, the association moved from one socket to |
| 325 | * another. We are currently sitting on the backlog of the |
| 326 | * old socket, so we need to move. |
| 327 | * However, since we are here in the process context we |
| 328 | * need to take make sure that the user doesn't own |
| 329 | * the new socket when we process the packet. |
| 330 | * If the new socket is user-owned, queue the chunk to the |
| 331 | * backlog of the new socket without dropping any refs. |
| 332 | * Otherwise, we can safely push the chunk on the inqueue. |
| 333 | */ |
Sridhar Samudrala | 7a48f92 | 2006-01-17 11:51:28 -0800 | [diff] [blame] | 334 | |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 335 | sk = rcvr->sk; |
| 336 | sctp_bh_lock_sock(sk); |
| 337 | |
| 338 | if (sock_owned_by_user(sk)) { |
| 339 | sk_add_backlog(sk, skb); |
| 340 | backloged = 1; |
| 341 | } else |
| 342 | sctp_inq_push(inqueue, chunk); |
| 343 | |
| 344 | sctp_bh_unlock_sock(sk); |
| 345 | |
| 346 | /* If the chunk was backloged again, don't drop refs */ |
| 347 | if (backloged) |
| 348 | return 0; |
| 349 | } else { |
| 350 | sctp_inq_push(inqueue, chunk); |
| 351 | } |
| 352 | |
| 353 | done: |
| 354 | /* Release the refs we took in sctp_add_backlog */ |
| 355 | if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type) |
| 356 | sctp_association_put(sctp_assoc(rcvr)); |
| 357 | else if (SCTP_EP_TYPE_SOCKET == rcvr->type) |
| 358 | sctp_endpoint_put(sctp_ep(rcvr)); |
| 359 | else |
| 360 | BUG(); |
| 361 | |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 362 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | } |
| 364 | |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 365 | static void sctp_add_backlog(struct sock *sk, struct sk_buff *skb) |
Sridhar Samudrala | c4d2444 | 2006-01-17 11:56:26 -0800 | [diff] [blame] | 366 | { |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 367 | struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk; |
| 368 | struct sctp_ep_common *rcvr = chunk->rcvr; |
Sridhar Samudrala | c4d2444 | 2006-01-17 11:56:26 -0800 | [diff] [blame] | 369 | |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 370 | /* Hold the assoc/ep while hanging on the backlog queue. |
| 371 | * This way, we know structures we need will not disappear from us |
| 372 | */ |
| 373 | if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type) |
| 374 | sctp_association_hold(sctp_assoc(rcvr)); |
| 375 | else if (SCTP_EP_TYPE_SOCKET == rcvr->type) |
| 376 | sctp_endpoint_hold(sctp_ep(rcvr)); |
| 377 | else |
| 378 | BUG(); |
Sridhar Samudrala | c4d2444 | 2006-01-17 11:56:26 -0800 | [diff] [blame] | 379 | |
Vladislav Yasevich | 61c9fed | 2006-05-19 11:01:18 -0700 | [diff] [blame] | 380 | sk_add_backlog(sk, skb); |
Sridhar Samudrala | c4d2444 | 2006-01-17 11:56:26 -0800 | [diff] [blame] | 381 | } |
| 382 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 383 | /* Handle icmp frag needed error. */ |
| 384 | void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc, |
| 385 | struct sctp_transport *t, __u32 pmtu) |
| 386 | { |
Wei Yongjun | 91bd6b1 | 2008-10-23 00:59:52 -0700 | [diff] [blame] | 387 | if (!t || (t->pathmtu <= pmtu)) |
Frank Filz | 52ccb8e | 2005-12-22 11:36:46 -0800 | [diff] [blame] | 388 | return; |
| 389 | |
Vlad Yasevich | 8a47949 | 2007-06-07 14:21:05 -0400 | [diff] [blame] | 390 | if (sock_owned_by_user(sk)) { |
| 391 | asoc->pmtu_pending = 1; |
| 392 | t->pmtu_pending = 1; |
| 393 | return; |
| 394 | } |
| 395 | |
Frank Filz | 52ccb8e | 2005-12-22 11:36:46 -0800 | [diff] [blame] | 396 | if (t->param_flags & SPP_PMTUD_ENABLE) { |
Vlad Yasevich | c910b47 | 2007-06-07 13:47:03 -0400 | [diff] [blame] | 397 | /* Update transports view of the MTU */ |
| 398 | sctp_transport_update_pmtu(t, pmtu); |
Frank Filz | 52ccb8e | 2005-12-22 11:36:46 -0800 | [diff] [blame] | 399 | |
| 400 | /* Update association pmtu. */ |
| 401 | sctp_assoc_sync_pmtu(asoc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | } |
| 403 | |
Frank Filz | 52ccb8e | 2005-12-22 11:36:46 -0800 | [diff] [blame] | 404 | /* Retransmit with the new pmtu setting. |
| 405 | * Normally, if PMTU discovery is disabled, an ICMP Fragmentation |
| 406 | * Needed will never be sent, but if a message was sent before |
| 407 | * PMTU discovery was disabled that was larger than the PMTU, it |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 408 | * would not be fragmented, so it must be re-transmitted fragmented. |
Frank Filz | 52ccb8e | 2005-12-22 11:36:46 -0800 | [diff] [blame] | 409 | */ |
| 410 | sctp_retransmit(&asoc->outqueue, t, SCTP_RTXR_PMTUD); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 411 | } |
| 412 | |
| 413 | /* |
| 414 | * SCTP Implementer's Guide, 2.37 ICMP handling procedures |
| 415 | * |
| 416 | * ICMP8) If the ICMP code is a "Unrecognized next header type encountered" |
| 417 | * or a "Protocol Unreachable" treat this message as an abort |
| 418 | * with the T bit set. |
| 419 | * |
| 420 | * This function sends an event to the state machine, which will abort the |
| 421 | * association. |
| 422 | * |
| 423 | */ |
| 424 | void sctp_icmp_proto_unreachable(struct sock *sk, |
YOSHIFUJI Hideaki | d808ad9 | 2007-02-09 23:25:18 +0900 | [diff] [blame] | 425 | struct sctp_association *asoc, |
| 426 | struct sctp_transport *t) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | { |
Harvey Harrison | 0dc4787 | 2008-03-05 20:47:47 -0800 | [diff] [blame] | 428 | SCTP_DEBUG_PRINTK("%s\n", __func__); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | |
| 430 | sctp_do_sm(SCTP_EVENT_T_OTHER, |
| 431 | SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH), |
Frank Filz | 3f7a87d | 2005-06-20 13:14:57 -0700 | [diff] [blame] | 432 | asoc->state, asoc->ep, asoc, t, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | GFP_ATOMIC); |
| 434 | |
| 435 | } |
| 436 | |
| 437 | /* Common lookup code for icmp/icmpv6 error handler. */ |
| 438 | struct sock *sctp_err_lookup(int family, struct sk_buff *skb, |
| 439 | struct sctphdr *sctphdr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 440 | struct sctp_association **app, |
| 441 | struct sctp_transport **tpp) |
| 442 | { |
| 443 | union sctp_addr saddr; |
| 444 | union sctp_addr daddr; |
| 445 | struct sctp_af *af; |
| 446 | struct sock *sk = NULL; |
Sridhar Samudrala | 8de8c87 | 2006-05-19 10:58:12 -0700 | [diff] [blame] | 447 | struct sctp_association *asoc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | struct sctp_transport *transport = NULL; |
Wei Yongjun | 7115e63 | 2008-06-19 16:07:48 -0700 | [diff] [blame] | 449 | struct sctp_init_chunk *chunkhdr; |
| 450 | __u32 vtag = ntohl(sctphdr->vtag); |
| 451 | int len = skb->len - ((void *)sctphdr - (void *)skb->data); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 452 | |
Sridhar Samudrala | d1ad1ff | 2005-07-18 13:44:10 -0700 | [diff] [blame] | 453 | *app = NULL; *tpp = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | |
| 455 | af = sctp_get_af_specific(family); |
| 456 | if (unlikely(!af)) { |
| 457 | return NULL; |
| 458 | } |
| 459 | |
| 460 | /* Initialize local addresses for lookups. */ |
| 461 | af->from_skb(&saddr, skb, 1); |
| 462 | af->from_skb(&daddr, skb, 0); |
| 463 | |
| 464 | /* Look for an association that matches the incoming ICMP error |
| 465 | * packet. |
| 466 | */ |
Al Viro | d55c41b | 2006-11-20 17:09:40 -0800 | [diff] [blame] | 467 | asoc = __sctp_lookup_association(&saddr, &daddr, &transport); |
Sridhar Samudrala | d1ad1ff | 2005-07-18 13:44:10 -0700 | [diff] [blame] | 468 | if (!asoc) |
| 469 | return NULL; |
| 470 | |
| 471 | sk = asoc->base.sk; |
| 472 | |
Wei Yongjun | 7115e63 | 2008-06-19 16:07:48 -0700 | [diff] [blame] | 473 | /* RFC 4960, Appendix C. ICMP Handling |
| 474 | * |
| 475 | * ICMP6) An implementation MUST validate that the Verification Tag |
| 476 | * contained in the ICMP message matches the Verification Tag of |
| 477 | * the peer. If the Verification Tag is not 0 and does NOT |
| 478 | * match, discard the ICMP message. If it is 0 and the ICMP |
| 479 | * message contains enough bytes to verify that the chunk type is |
| 480 | * an INIT chunk and that the Initiate Tag matches the tag of the |
| 481 | * peer, continue with ICMP7. If the ICMP message is too short |
| 482 | * or the chunk type or the Initiate Tag does not match, silently |
| 483 | * discard the packet. |
| 484 | */ |
| 485 | if (vtag == 0) { |
| 486 | chunkhdr = (struct sctp_init_chunk *)((void *)sctphdr |
| 487 | + sizeof(struct sctphdr)); |
| 488 | if (len < sizeof(struct sctphdr) + sizeof(sctp_chunkhdr_t) |
| 489 | + sizeof(__be32) || |
| 490 | chunkhdr->chunk_hdr.type != SCTP_CID_INIT || |
| 491 | ntohl(chunkhdr->init_hdr.init_tag) != asoc->c.my_vtag) { |
| 492 | goto out; |
| 493 | } |
| 494 | } else if (vtag != asoc->c.peer_vtag) { |
Sridhar Samudrala | d1ad1ff | 2005-07-18 13:44:10 -0700 | [diff] [blame] | 495 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 496 | } |
| 497 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | sctp_bh_lock_sock(sk); |
| 499 | |
| 500 | /* If too many ICMPs get dropped on busy |
| 501 | * servers this needs to be solved differently. |
| 502 | */ |
| 503 | if (sock_owned_by_user(sk)) |
Pavel Emelyanov | de0744a | 2008-07-16 20:31:16 -0700 | [diff] [blame] | 504 | NET_INC_STATS_BH(&init_net, LINUX_MIB_LOCKDROPPEDICMPS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | *app = asoc; |
| 507 | *tpp = transport; |
| 508 | return sk; |
| 509 | |
| 510 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 511 | if (asoc) |
| 512 | sctp_association_put(asoc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 513 | return NULL; |
| 514 | } |
| 515 | |
| 516 | /* Common cleanup code for icmp/icmpv6 error handler. */ |
Sridhar Samudrala | d1ad1ff | 2005-07-18 13:44:10 -0700 | [diff] [blame] | 517 | void sctp_err_finish(struct sock *sk, struct sctp_association *asoc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | { |
| 519 | sctp_bh_unlock_sock(sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 520 | if (asoc) |
| 521 | sctp_association_put(asoc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 522 | } |
| 523 | |
| 524 | /* |
| 525 | * This routine is called by the ICMP module when it gets some |
| 526 | * sort of error condition. If err < 0 then the socket should |
| 527 | * be closed and the error returned to the user. If err > 0 |
| 528 | * it's just the icmp type << 8 | icmp code. After adjustment |
| 529 | * header points to the first 8 bytes of the sctp header. We need |
| 530 | * to find the appropriate port. |
| 531 | * |
| 532 | * The locking strategy used here is very "optimistic". When |
| 533 | * someone else accesses the socket the ICMP is just dropped |
| 534 | * and for some paths there is no check at all. |
| 535 | * A more general error queue to queue errors for later handling |
| 536 | * is probably better. |
| 537 | * |
| 538 | */ |
| 539 | void sctp_v4_err(struct sk_buff *skb, __u32 info) |
| 540 | { |
| 541 | struct iphdr *iph = (struct iphdr *)skb->data; |
Arnaldo Carvalho de Melo | a27ef74 | 2007-03-13 17:17:10 -0300 | [diff] [blame] | 542 | const int ihlen = iph->ihl * 4; |
Arnaldo Carvalho de Melo | 88c7664 | 2007-03-13 14:43:18 -0300 | [diff] [blame] | 543 | const int type = icmp_hdr(skb)->type; |
| 544 | const int code = icmp_hdr(skb)->code; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 545 | struct sock *sk; |
Sridhar Samudrala | 8de8c87 | 2006-05-19 10:58:12 -0700 | [diff] [blame] | 546 | struct sctp_association *asoc = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 547 | struct sctp_transport *transport; |
| 548 | struct inet_sock *inet; |
Arnaldo Carvalho de Melo | 2e07fa9 | 2007-04-10 21:22:35 -0700 | [diff] [blame] | 549 | sk_buff_data_t saveip, savesctp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 550 | int err; |
| 551 | |
Arnaldo Carvalho de Melo | a27ef74 | 2007-03-13 17:17:10 -0300 | [diff] [blame] | 552 | if (skb->len < ihlen + 8) { |
Pavel Emelyanov | dcfc23c | 2008-07-14 23:03:00 -0700 | [diff] [blame] | 553 | ICMP_INC_STATS_BH(&init_net, ICMP_MIB_INERRORS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | return; |
| 555 | } |
| 556 | |
| 557 | /* Fix up skb to look at the embedded net header. */ |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 558 | saveip = skb->network_header; |
| 559 | savesctp = skb->transport_header; |
Arnaldo Carvalho de Melo | 31c7711 | 2007-03-10 19:04:55 -0300 | [diff] [blame] | 560 | skb_reset_network_header(skb); |
Arnaldo Carvalho de Melo | a27ef74 | 2007-03-13 17:17:10 -0300 | [diff] [blame] | 561 | skb_set_transport_header(skb, ihlen); |
| 562 | sk = sctp_err_lookup(AF_INET, skb, sctp_hdr(skb), &asoc, &transport); |
Arnaldo Carvalho de Melo | 2e07fa9 | 2007-04-10 21:22:35 -0700 | [diff] [blame] | 563 | /* Put back, the original values. */ |
Arnaldo Carvalho de Melo | b0e380b | 2007-04-10 21:21:55 -0700 | [diff] [blame] | 564 | skb->network_header = saveip; |
| 565 | skb->transport_header = savesctp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | if (!sk) { |
Pavel Emelyanov | dcfc23c | 2008-07-14 23:03:00 -0700 | [diff] [blame] | 567 | ICMP_INC_STATS_BH(&init_net, ICMP_MIB_INERRORS); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 568 | return; |
| 569 | } |
| 570 | /* Warning: The sock lock is held. Remember to call |
| 571 | * sctp_err_finish! |
| 572 | */ |
| 573 | |
| 574 | switch (type) { |
| 575 | case ICMP_PARAMETERPROB: |
| 576 | err = EPROTO; |
| 577 | break; |
| 578 | case ICMP_DEST_UNREACH: |
| 579 | if (code > NR_ICMP_UNREACH) |
| 580 | goto out_unlock; |
| 581 | |
| 582 | /* PMTU discovery (RFC1191) */ |
| 583 | if (ICMP_FRAG_NEEDED == code) { |
| 584 | sctp_icmp_frag_needed(sk, asoc, transport, info); |
| 585 | goto out_unlock; |
| 586 | } |
| 587 | else { |
| 588 | if (ICMP_PROT_UNREACH == code) { |
Sridhar Samudrala | d1ad1ff | 2005-07-18 13:44:10 -0700 | [diff] [blame] | 589 | sctp_icmp_proto_unreachable(sk, asoc, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 590 | transport); |
| 591 | goto out_unlock; |
| 592 | } |
| 593 | } |
| 594 | err = icmp_err_convert[code].errno; |
| 595 | break; |
| 596 | case ICMP_TIME_EXCEEDED: |
| 597 | /* Ignore any time exceeded errors due to fragment reassembly |
| 598 | * timeouts. |
| 599 | */ |
| 600 | if (ICMP_EXC_FRAGTIME == code) |
| 601 | goto out_unlock; |
| 602 | |
| 603 | err = EHOSTUNREACH; |
| 604 | break; |
| 605 | default: |
| 606 | goto out_unlock; |
| 607 | } |
| 608 | |
| 609 | inet = inet_sk(sk); |
| 610 | if (!sock_owned_by_user(sk) && inet->recverr) { |
| 611 | sk->sk_err = err; |
| 612 | sk->sk_error_report(sk); |
| 613 | } else { /* Only an error on timeout */ |
| 614 | sk->sk_err_soft = err; |
| 615 | } |
| 616 | |
| 617 | out_unlock: |
Sridhar Samudrala | d1ad1ff | 2005-07-18 13:44:10 -0700 | [diff] [blame] | 618 | sctp_err_finish(sk, asoc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 619 | } |
| 620 | |
| 621 | /* |
| 622 | * RFC 2960, 8.4 - Handle "Out of the blue" Packets. |
| 623 | * |
| 624 | * This function scans all the chunks in the OOTB packet to determine if |
| 625 | * the packet should be discarded right away. If a response might be needed |
| 626 | * for this packet, or, if further processing is possible, the packet will |
| 627 | * be queued to a proper inqueue for the next phase of handling. |
| 628 | * |
| 629 | * Output: |
| 630 | * Return 0 - If further processing is needed. |
| 631 | * Return 1 - If the packet can be discarded right away. |
| 632 | */ |
sebastian@breakpoint.cc | 0467521 | 2007-07-26 23:21:31 +0200 | [diff] [blame] | 633 | static int sctp_rcv_ootb(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | { |
| 635 | sctp_chunkhdr_t *ch; |
| 636 | __u8 *ch_end; |
| 637 | sctp_errhdr_t *err; |
| 638 | |
| 639 | ch = (sctp_chunkhdr_t *) skb->data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 640 | |
| 641 | /* Scan through all the chunks in the packet. */ |
Tsutomu Fujii | a7d1f1b | 2006-01-17 11:57:09 -0800 | [diff] [blame] | 642 | do { |
| 643 | /* Break out if chunk length is less then minimal. */ |
| 644 | if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t)) |
| 645 | break; |
| 646 | |
| 647 | ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length)); |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 648 | if (ch_end > skb_tail_pointer(skb)) |
Tsutomu Fujii | a7d1f1b | 2006-01-17 11:57:09 -0800 | [diff] [blame] | 649 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 650 | |
| 651 | /* RFC 8.4, 2) If the OOTB packet contains an ABORT chunk, the |
| 652 | * receiver MUST silently discard the OOTB packet and take no |
| 653 | * further action. |
| 654 | */ |
| 655 | if (SCTP_CID_ABORT == ch->type) |
| 656 | goto discard; |
| 657 | |
| 658 | /* RFC 8.4, 6) If the packet contains a SHUTDOWN COMPLETE |
| 659 | * chunk, the receiver should silently discard the packet |
| 660 | * and take no further action. |
| 661 | */ |
| 662 | if (SCTP_CID_SHUTDOWN_COMPLETE == ch->type) |
| 663 | goto discard; |
| 664 | |
Vlad Yasevich | 3c77f96 | 2007-09-17 15:14:28 -0400 | [diff] [blame] | 665 | /* RFC 4460, 2.11.2 |
| 666 | * This will discard packets with INIT chunk bundled as |
| 667 | * subsequent chunks in the packet. When INIT is first, |
| 668 | * the normal INIT processing will discard the chunk. |
| 669 | */ |
| 670 | if (SCTP_CID_INIT == ch->type && (void *)ch != skb->data) |
| 671 | goto discard; |
| 672 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 673 | /* RFC 8.4, 7) If the packet contains a "Stale cookie" ERROR |
| 674 | * or a COOKIE ACK the SCTP Packet should be silently |
| 675 | * discarded. |
| 676 | */ |
| 677 | if (SCTP_CID_COOKIE_ACK == ch->type) |
| 678 | goto discard; |
| 679 | |
| 680 | if (SCTP_CID_ERROR == ch->type) { |
| 681 | sctp_walk_errors(err, ch) { |
| 682 | if (SCTP_ERROR_STALE_COOKIE == err->cause) |
| 683 | goto discard; |
| 684 | } |
| 685 | } |
| 686 | |
| 687 | ch = (sctp_chunkhdr_t *) ch_end; |
Arnaldo Carvalho de Melo | 27a884d | 2007-04-19 20:29:13 -0700 | [diff] [blame] | 688 | } while (ch_end < skb_tail_pointer(skb)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 689 | |
| 690 | return 0; |
| 691 | |
| 692 | discard: |
| 693 | return 1; |
| 694 | } |
| 695 | |
| 696 | /* Insert endpoint into the hash table. */ |
| 697 | static void __sctp_hash_endpoint(struct sctp_endpoint *ep) |
| 698 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | struct sctp_ep_common *epb; |
| 700 | struct sctp_hashbucket *head; |
| 701 | |
| 702 | epb = &ep->base; |
| 703 | |
| 704 | epb->hashent = sctp_ep_hashfn(epb->bind_addr.port); |
| 705 | head = &sctp_ep_hashtable[epb->hashent]; |
| 706 | |
| 707 | sctp_write_lock(&head->lock); |
Vlad Yasevich | d970dbf | 2007-11-09 11:43:40 -0500 | [diff] [blame] | 708 | hlist_add_head(&epb->node, &head->chain); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 709 | sctp_write_unlock(&head->lock); |
| 710 | } |
| 711 | |
| 712 | /* Add an endpoint to the hash. Local BH-safe. */ |
| 713 | void sctp_hash_endpoint(struct sctp_endpoint *ep) |
| 714 | { |
| 715 | sctp_local_bh_disable(); |
| 716 | __sctp_hash_endpoint(ep); |
| 717 | sctp_local_bh_enable(); |
| 718 | } |
| 719 | |
| 720 | /* Remove endpoint from the hash table. */ |
| 721 | static void __sctp_unhash_endpoint(struct sctp_endpoint *ep) |
| 722 | { |
| 723 | struct sctp_hashbucket *head; |
| 724 | struct sctp_ep_common *epb; |
| 725 | |
| 726 | epb = &ep->base; |
| 727 | |
Vlad Yasevich | d970dbf | 2007-11-09 11:43:40 -0500 | [diff] [blame] | 728 | if (hlist_unhashed(&epb->node)) |
| 729 | return; |
| 730 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 731 | epb->hashent = sctp_ep_hashfn(epb->bind_addr.port); |
| 732 | |
| 733 | head = &sctp_ep_hashtable[epb->hashent]; |
| 734 | |
| 735 | sctp_write_lock(&head->lock); |
Vlad Yasevich | d970dbf | 2007-11-09 11:43:40 -0500 | [diff] [blame] | 736 | __hlist_del(&epb->node); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 737 | sctp_write_unlock(&head->lock); |
| 738 | } |
| 739 | |
| 740 | /* Remove endpoint from the hash. Local BH-safe. */ |
| 741 | void sctp_unhash_endpoint(struct sctp_endpoint *ep) |
| 742 | { |
| 743 | sctp_local_bh_disable(); |
| 744 | __sctp_unhash_endpoint(ep); |
| 745 | sctp_local_bh_enable(); |
| 746 | } |
| 747 | |
| 748 | /* Look up an endpoint. */ |
| 749 | static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *laddr) |
| 750 | { |
| 751 | struct sctp_hashbucket *head; |
| 752 | struct sctp_ep_common *epb; |
| 753 | struct sctp_endpoint *ep; |
Vlad Yasevich | d970dbf | 2007-11-09 11:43:40 -0500 | [diff] [blame] | 754 | struct hlist_node *node; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 755 | int hash; |
| 756 | |
Al Viro | 1c7d1fc | 2006-11-20 17:08:09 -0800 | [diff] [blame] | 757 | hash = sctp_ep_hashfn(ntohs(laddr->v4.sin_port)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | head = &sctp_ep_hashtable[hash]; |
| 759 | read_lock(&head->lock); |
Vlad Yasevich | d970dbf | 2007-11-09 11:43:40 -0500 | [diff] [blame] | 760 | sctp_for_each_hentry(epb, node, &head->chain) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 761 | ep = sctp_ep(epb); |
| 762 | if (sctp_endpoint_is_match(ep, laddr)) |
| 763 | goto hit; |
| 764 | } |
| 765 | |
| 766 | ep = sctp_sk((sctp_get_ctl_sock()))->ep; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 767 | |
| 768 | hit: |
| 769 | sctp_endpoint_hold(ep); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 770 | read_unlock(&head->lock); |
| 771 | return ep; |
| 772 | } |
| 773 | |
| 774 | /* Insert association into the hash table. */ |
| 775 | static void __sctp_hash_established(struct sctp_association *asoc) |
| 776 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 777 | struct sctp_ep_common *epb; |
| 778 | struct sctp_hashbucket *head; |
| 779 | |
| 780 | epb = &asoc->base; |
| 781 | |
| 782 | /* Calculate which chain this entry will belong to. */ |
| 783 | epb->hashent = sctp_assoc_hashfn(epb->bind_addr.port, asoc->peer.port); |
| 784 | |
| 785 | head = &sctp_assoc_hashtable[epb->hashent]; |
| 786 | |
| 787 | sctp_write_lock(&head->lock); |
Vlad Yasevich | d970dbf | 2007-11-09 11:43:40 -0500 | [diff] [blame] | 788 | hlist_add_head(&epb->node, &head->chain); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 789 | sctp_write_unlock(&head->lock); |
| 790 | } |
| 791 | |
| 792 | /* Add an association to the hash. Local BH-safe. */ |
| 793 | void sctp_hash_established(struct sctp_association *asoc) |
| 794 | { |
Vlad Yasevich | de76e69 | 2006-10-30 18:55:11 -0800 | [diff] [blame] | 795 | if (asoc->temp) |
| 796 | return; |
| 797 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | sctp_local_bh_disable(); |
| 799 | __sctp_hash_established(asoc); |
| 800 | sctp_local_bh_enable(); |
| 801 | } |
| 802 | |
| 803 | /* Remove association from the hash table. */ |
| 804 | static void __sctp_unhash_established(struct sctp_association *asoc) |
| 805 | { |
| 806 | struct sctp_hashbucket *head; |
| 807 | struct sctp_ep_common *epb; |
| 808 | |
| 809 | epb = &asoc->base; |
| 810 | |
| 811 | epb->hashent = sctp_assoc_hashfn(epb->bind_addr.port, |
| 812 | asoc->peer.port); |
| 813 | |
| 814 | head = &sctp_assoc_hashtable[epb->hashent]; |
| 815 | |
| 816 | sctp_write_lock(&head->lock); |
Vlad Yasevich | d970dbf | 2007-11-09 11:43:40 -0500 | [diff] [blame] | 817 | __hlist_del(&epb->node); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 818 | sctp_write_unlock(&head->lock); |
| 819 | } |
| 820 | |
| 821 | /* Remove association from the hash table. Local BH-safe. */ |
| 822 | void sctp_unhash_established(struct sctp_association *asoc) |
| 823 | { |
Vlad Yasevich | de76e69 | 2006-10-30 18:55:11 -0800 | [diff] [blame] | 824 | if (asoc->temp) |
| 825 | return; |
| 826 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 827 | sctp_local_bh_disable(); |
| 828 | __sctp_unhash_established(asoc); |
| 829 | sctp_local_bh_enable(); |
| 830 | } |
| 831 | |
| 832 | /* Look up an association. */ |
| 833 | static struct sctp_association *__sctp_lookup_association( |
| 834 | const union sctp_addr *local, |
| 835 | const union sctp_addr *peer, |
| 836 | struct sctp_transport **pt) |
| 837 | { |
| 838 | struct sctp_hashbucket *head; |
| 839 | struct sctp_ep_common *epb; |
| 840 | struct sctp_association *asoc; |
| 841 | struct sctp_transport *transport; |
Vlad Yasevich | d970dbf | 2007-11-09 11:43:40 -0500 | [diff] [blame] | 842 | struct hlist_node *node; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 843 | int hash; |
| 844 | |
| 845 | /* Optimize here for direct hit, only listening connections can |
| 846 | * have wildcards anyways. |
| 847 | */ |
Al Viro | e2fcced | 2006-11-20 17:08:41 -0800 | [diff] [blame] | 848 | hash = sctp_assoc_hashfn(ntohs(local->v4.sin_port), ntohs(peer->v4.sin_port)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 849 | head = &sctp_assoc_hashtable[hash]; |
| 850 | read_lock(&head->lock); |
Vlad Yasevich | d970dbf | 2007-11-09 11:43:40 -0500 | [diff] [blame] | 851 | sctp_for_each_hentry(epb, node, &head->chain) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 852 | asoc = sctp_assoc(epb); |
| 853 | transport = sctp_assoc_is_match(asoc, local, peer); |
| 854 | if (transport) |
| 855 | goto hit; |
| 856 | } |
| 857 | |
| 858 | read_unlock(&head->lock); |
| 859 | |
| 860 | return NULL; |
| 861 | |
| 862 | hit: |
| 863 | *pt = transport; |
| 864 | sctp_association_hold(asoc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 865 | read_unlock(&head->lock); |
| 866 | return asoc; |
| 867 | } |
| 868 | |
| 869 | /* Look up an association. BH-safe. */ |
| 870 | SCTP_STATIC |
| 871 | struct sctp_association *sctp_lookup_association(const union sctp_addr *laddr, |
| 872 | const union sctp_addr *paddr, |
| 873 | struct sctp_transport **transportp) |
| 874 | { |
| 875 | struct sctp_association *asoc; |
| 876 | |
| 877 | sctp_local_bh_disable(); |
| 878 | asoc = __sctp_lookup_association(laddr, paddr, transportp); |
| 879 | sctp_local_bh_enable(); |
| 880 | |
| 881 | return asoc; |
| 882 | } |
| 883 | |
| 884 | /* Is there an association matching the given local and peer addresses? */ |
| 885 | int sctp_has_association(const union sctp_addr *laddr, |
| 886 | const union sctp_addr *paddr) |
| 887 | { |
| 888 | struct sctp_association *asoc; |
| 889 | struct sctp_transport *transport; |
| 890 | |
Al Viro | 6c7be55 | 2006-11-20 17:11:50 -0800 | [diff] [blame] | 891 | if ((asoc = sctp_lookup_association(laddr, paddr, &transport))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 892 | sctp_association_put(asoc); |
| 893 | return 1; |
| 894 | } |
| 895 | |
| 896 | return 0; |
| 897 | } |
| 898 | |
| 899 | /* |
| 900 | * SCTP Implementors Guide, 2.18 Handling of address |
| 901 | * parameters within the INIT or INIT-ACK. |
| 902 | * |
| 903 | * D) When searching for a matching TCB upon reception of an INIT |
| 904 | * or INIT-ACK chunk the receiver SHOULD use not only the |
| 905 | * source address of the packet (containing the INIT or |
| 906 | * INIT-ACK) but the receiver SHOULD also use all valid |
| 907 | * address parameters contained within the chunk. |
| 908 | * |
| 909 | * 2.18.3 Solution description |
| 910 | * |
| 911 | * This new text clearly specifies to an implementor the need |
| 912 | * to look within the INIT or INIT-ACK. Any implementation that |
| 913 | * does not do this, may not be able to establish associations |
| 914 | * in certain circumstances. |
| 915 | * |
| 916 | */ |
| 917 | static struct sctp_association *__sctp_rcv_init_lookup(struct sk_buff *skb, |
| 918 | const union sctp_addr *laddr, struct sctp_transport **transportp) |
| 919 | { |
| 920 | struct sctp_association *asoc; |
| 921 | union sctp_addr addr; |
| 922 | union sctp_addr *paddr = &addr; |
Arnaldo Carvalho de Melo | 2c0fd38 | 2007-03-13 13:59:32 -0300 | [diff] [blame] | 923 | struct sctphdr *sh = sctp_hdr(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 924 | sctp_chunkhdr_t *ch; |
| 925 | union sctp_params params; |
| 926 | sctp_init_chunk_t *init; |
| 927 | struct sctp_transport *transport; |
| 928 | struct sctp_af *af; |
| 929 | |
| 930 | ch = (sctp_chunkhdr_t *) skb->data; |
| 931 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 932 | /* |
| 933 | * This code will NOT touch anything inside the chunk--it is |
| 934 | * strictly READ-ONLY. |
| 935 | * |
| 936 | * RFC 2960 3 SCTP packet Format |
| 937 | * |
| 938 | * Multiple chunks can be bundled into one SCTP packet up to |
| 939 | * the MTU size, except for the INIT, INIT ACK, and SHUTDOWN |
| 940 | * COMPLETE chunks. These chunks MUST NOT be bundled with any |
| 941 | * other chunk in a packet. See Section 6.10 for more details |
| 942 | * on chunk bundling. |
| 943 | */ |
| 944 | |
| 945 | /* Find the start of the TLVs and the end of the chunk. This is |
| 946 | * the region we search for address parameters. |
| 947 | */ |
| 948 | init = (sctp_init_chunk_t *)skb->data; |
| 949 | |
| 950 | /* Walk the parameters looking for embedded addresses. */ |
| 951 | sctp_walk_params(params, init, init_hdr.params) { |
| 952 | |
| 953 | /* Note: Ignoring hostname addresses. */ |
| 954 | af = sctp_get_af_specific(param_type2af(params.p->type)); |
| 955 | if (!af) |
| 956 | continue; |
| 957 | |
Al Viro | dd86d13 | 2006-11-20 17:11:13 -0800 | [diff] [blame] | 958 | af->from_addr_param(paddr, params.addr, sh->source, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 959 | |
Al Viro | dd86d13 | 2006-11-20 17:11:13 -0800 | [diff] [blame] | 960 | asoc = __sctp_lookup_association(laddr, paddr, &transport); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 961 | if (asoc) |
| 962 | return asoc; |
| 963 | } |
| 964 | |
| 965 | return NULL; |
| 966 | } |
| 967 | |
Vlad Yasevich | df21857 | 2007-12-20 14:10:38 -0800 | [diff] [blame] | 968 | /* ADD-IP, Section 5.2 |
| 969 | * When an endpoint receives an ASCONF Chunk from the remote peer |
| 970 | * special procedures may be needed to identify the association the |
| 971 | * ASCONF Chunk is associated with. To properly find the association |
| 972 | * the following procedures SHOULD be followed: |
| 973 | * |
| 974 | * D2) If the association is not found, use the address found in the |
| 975 | * Address Parameter TLV combined with the port number found in the |
| 976 | * SCTP common header. If found proceed to rule D4. |
| 977 | * |
| 978 | * D2-ext) If more than one ASCONF Chunks are packed together, use the |
| 979 | * address found in the ASCONF Address Parameter TLV of each of the |
| 980 | * subsequent ASCONF Chunks. If found, proceed to rule D4. |
| 981 | */ |
| 982 | static struct sctp_association *__sctp_rcv_asconf_lookup( |
| 983 | sctp_chunkhdr_t *ch, |
| 984 | const union sctp_addr *laddr, |
Al Viro | bc92dd1 | 2008-03-17 22:47:32 -0700 | [diff] [blame] | 985 | __be16 peer_port, |
Vlad Yasevich | df21857 | 2007-12-20 14:10:38 -0800 | [diff] [blame] | 986 | struct sctp_transport **transportp) |
| 987 | { |
| 988 | sctp_addip_chunk_t *asconf = (struct sctp_addip_chunk *)ch; |
| 989 | struct sctp_af *af; |
| 990 | union sctp_addr_param *param; |
| 991 | union sctp_addr paddr; |
| 992 | |
| 993 | /* Skip over the ADDIP header and find the Address parameter */ |
| 994 | param = (union sctp_addr_param *)(asconf + 1); |
| 995 | |
| 996 | af = sctp_get_af_specific(param_type2af(param->v4.param_hdr.type)); |
| 997 | if (unlikely(!af)) |
| 998 | return NULL; |
| 999 | |
| 1000 | af->from_addr_param(&paddr, param, peer_port, 0); |
| 1001 | |
| 1002 | return __sctp_lookup_association(laddr, &paddr, transportp); |
| 1003 | } |
| 1004 | |
| 1005 | |
Vlad Yasevich | bbd0d59 | 2007-10-03 17:51:34 -0700 | [diff] [blame] | 1006 | /* SCTP-AUTH, Section 6.3: |
| 1007 | * If the receiver does not find a STCB for a packet containing an AUTH |
| 1008 | * chunk as the first chunk and not a COOKIE-ECHO chunk as the second |
| 1009 | * chunk, it MUST use the chunks after the AUTH chunk to look up an existing |
| 1010 | * association. |
| 1011 | * |
| 1012 | * This means that any chunks that can help us identify the association need |
| 1013 | * to be looked at to find this assocation. |
Vlad Yasevich | bbd0d59 | 2007-10-03 17:51:34 -0700 | [diff] [blame] | 1014 | */ |
Vlad Yasevich | df21857 | 2007-12-20 14:10:38 -0800 | [diff] [blame] | 1015 | static struct sctp_association *__sctp_rcv_walk_lookup(struct sk_buff *skb, |
Vlad Yasevich | bbd0d59 | 2007-10-03 17:51:34 -0700 | [diff] [blame] | 1016 | const union sctp_addr *laddr, |
| 1017 | struct sctp_transport **transportp) |
| 1018 | { |
Vlad Yasevich | df21857 | 2007-12-20 14:10:38 -0800 | [diff] [blame] | 1019 | struct sctp_association *asoc = NULL; |
| 1020 | sctp_chunkhdr_t *ch; |
| 1021 | int have_auth = 0; |
| 1022 | unsigned int chunk_num = 1; |
| 1023 | __u8 *ch_end; |
| 1024 | |
| 1025 | /* Walk through the chunks looking for AUTH or ASCONF chunks |
| 1026 | * to help us find the association. |
Vlad Yasevich | bbd0d59 | 2007-10-03 17:51:34 -0700 | [diff] [blame] | 1027 | */ |
Vlad Yasevich | df21857 | 2007-12-20 14:10:38 -0800 | [diff] [blame] | 1028 | ch = (sctp_chunkhdr_t *) skb->data; |
| 1029 | do { |
| 1030 | /* Break out if chunk length is less then minimal. */ |
| 1031 | if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t)) |
| 1032 | break; |
| 1033 | |
| 1034 | ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length)); |
| 1035 | if (ch_end > skb_tail_pointer(skb)) |
| 1036 | break; |
| 1037 | |
| 1038 | switch(ch->type) { |
| 1039 | case SCTP_CID_AUTH: |
| 1040 | have_auth = chunk_num; |
| 1041 | break; |
| 1042 | |
| 1043 | case SCTP_CID_COOKIE_ECHO: |
| 1044 | /* If a packet arrives containing an AUTH chunk as |
| 1045 | * a first chunk, a COOKIE-ECHO chunk as the second |
| 1046 | * chunk, and possibly more chunks after them, and |
| 1047 | * the receiver does not have an STCB for that |
| 1048 | * packet, then authentication is based on |
| 1049 | * the contents of the COOKIE- ECHO chunk. |
| 1050 | */ |
| 1051 | if (have_auth == 1 && chunk_num == 2) |
| 1052 | return NULL; |
| 1053 | break; |
| 1054 | |
| 1055 | case SCTP_CID_ASCONF: |
| 1056 | if (have_auth || sctp_addip_noauth) |
| 1057 | asoc = __sctp_rcv_asconf_lookup(ch, laddr, |
| 1058 | sctp_hdr(skb)->source, |
| 1059 | transportp); |
| 1060 | default: |
| 1061 | break; |
| 1062 | } |
| 1063 | |
| 1064 | if (asoc) |
| 1065 | break; |
| 1066 | |
| 1067 | ch = (sctp_chunkhdr_t *) ch_end; |
| 1068 | chunk_num++; |
| 1069 | } while (ch_end < skb_tail_pointer(skb)); |
| 1070 | |
| 1071 | return asoc; |
Vlad Yasevich | bbd0d59 | 2007-10-03 17:51:34 -0700 | [diff] [blame] | 1072 | } |
| 1073 | |
| 1074 | /* |
| 1075 | * There are circumstances when we need to look inside the SCTP packet |
| 1076 | * for information to help us find the association. Examples |
| 1077 | * include looking inside of INIT/INIT-ACK chunks or after the AUTH |
| 1078 | * chunks. |
| 1079 | */ |
| 1080 | static struct sctp_association *__sctp_rcv_lookup_harder(struct sk_buff *skb, |
Vlad Yasevich | bbd0d59 | 2007-10-03 17:51:34 -0700 | [diff] [blame] | 1081 | const union sctp_addr *laddr, |
| 1082 | struct sctp_transport **transportp) |
| 1083 | { |
| 1084 | sctp_chunkhdr_t *ch; |
| 1085 | |
| 1086 | ch = (sctp_chunkhdr_t *) skb->data; |
| 1087 | |
Vlad Yasevich | df21857 | 2007-12-20 14:10:38 -0800 | [diff] [blame] | 1088 | /* The code below will attempt to walk the chunk and extract |
| 1089 | * parameter information. Before we do that, we need to verify |
| 1090 | * that the chunk length doesn't cause overflow. Otherwise, we'll |
| 1091 | * walk off the end. |
| 1092 | */ |
| 1093 | if (WORD_ROUND(ntohs(ch->length)) > skb->len) |
| 1094 | return NULL; |
| 1095 | |
Vlad Yasevich | bbd0d59 | 2007-10-03 17:51:34 -0700 | [diff] [blame] | 1096 | /* If this is INIT/INIT-ACK look inside the chunk too. */ |
| 1097 | switch (ch->type) { |
| 1098 | case SCTP_CID_INIT: |
| 1099 | case SCTP_CID_INIT_ACK: |
| 1100 | return __sctp_rcv_init_lookup(skb, laddr, transportp); |
| 1101 | break; |
| 1102 | |
Vlad Yasevich | df21857 | 2007-12-20 14:10:38 -0800 | [diff] [blame] | 1103 | default: |
| 1104 | return __sctp_rcv_walk_lookup(skb, laddr, transportp); |
Vlad Yasevich | bbd0d59 | 2007-10-03 17:51:34 -0700 | [diff] [blame] | 1105 | break; |
| 1106 | } |
| 1107 | |
Vlad Yasevich | df21857 | 2007-12-20 14:10:38 -0800 | [diff] [blame] | 1108 | |
Vlad Yasevich | bbd0d59 | 2007-10-03 17:51:34 -0700 | [diff] [blame] | 1109 | return NULL; |
| 1110 | } |
| 1111 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1112 | /* Lookup an association for an inbound skb. */ |
| 1113 | static struct sctp_association *__sctp_rcv_lookup(struct sk_buff *skb, |
| 1114 | const union sctp_addr *paddr, |
| 1115 | const union sctp_addr *laddr, |
| 1116 | struct sctp_transport **transportp) |
| 1117 | { |
| 1118 | struct sctp_association *asoc; |
| 1119 | |
| 1120 | asoc = __sctp_lookup_association(laddr, paddr, transportp); |
| 1121 | |
| 1122 | /* Further lookup for INIT/INIT-ACK packets. |
| 1123 | * SCTP Implementors Guide, 2.18 Handling of address |
| 1124 | * parameters within the INIT or INIT-ACK. |
| 1125 | */ |
| 1126 | if (!asoc) |
Vlad Yasevich | df21857 | 2007-12-20 14:10:38 -0800 | [diff] [blame] | 1127 | asoc = __sctp_rcv_lookup_harder(skb, laddr, transportp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1128 | |
| 1129 | return asoc; |
| 1130 | } |