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1 /* SCTP kernel implementation !! 1 /* SCTP kernel reference Implementation
2 * Copyright (c) 1999-2000 Cisco, Inc. 2 * Copyright (c) 1999-2000 Cisco, Inc.
3 * Copyright (c) 1999-2001 Motorola, Inc. 3 * Copyright (c) 1999-2001 Motorola, Inc.
4 * Copyright (c) 2001-2003 International Busin 4 * Copyright (c) 2001-2003 International Business Machines, Corp.
5 * Copyright (c) 2001 Intel Corp. 5 * Copyright (c) 2001 Intel Corp.
6 * Copyright (c) 2001 Nokia, Inc. 6 * Copyright (c) 2001 Nokia, Inc.
7 * Copyright (c) 2001 La Monte H.P. Yarroll 7 * Copyright (c) 2001 La Monte H.P. Yarroll
8 * 8 *
9 * This file is part of the SCTP kernel implem !! 9 * This file is part of the SCTP kernel reference Implementation
10 * 10 *
11 * These functions handle all input from the I 11 * These functions handle all input from the IP layer into SCTP.
12 * 12 *
13 * This SCTP implementation is free software; !! 13 * The SCTP reference implementation is free software;
14 * you can redistribute it and/or modify it un 14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published 15 * the GNU General Public License as published by
16 * the Free Software Foundation; either versio 16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version. 17 * any later version.
18 * 18 *
19 * This SCTP implementation is distributed in !! 19 * The SCTP reference implementation is distributed in the hope that it
20 * will be useful, but WITHOUT ANY WARRANTY; w 20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************ 21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR 22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more 23 * See the GNU General Public License for more details.
24 * 24 *
25 * You should have received a copy of the GNU 25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. I 26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Pla 27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA. 28 * Boston, MA 02111-1307, USA.
29 * 29 *
30 * Please send any bug reports or fixes you ma 30 * Please send any bug reports or fixes you make to the
31 * email address(es): 31 * email address(es):
32 * lksctp developers <lksctp-developers@lis 32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
33 * 33 *
34 * Or submit a bug report through the followin 34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp 35 * http://www.sf.net/projects/lksctp
36 * 36 *
37 * Written or modified by: 37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org> 38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us> 39 * Karl Knutson <karl@athena.chicago.il.us>
40 * Xingang Guo <xingang.guo@intel.com> 40 * Xingang Guo <xingang.guo@intel.com>
41 * Jon Grimm <jgrimm@us.ibm.com> 41 * Jon Grimm <jgrimm@us.ibm.com>
42 * Hui Huang <hui.huang@nokia.com> 42 * Hui Huang <hui.huang@nokia.com>
43 * Daisy Chang <daisyc@us.ibm.com> 43 * Daisy Chang <daisyc@us.ibm.com>
44 * Sridhar Samudrala <sri@us.ibm.com> 44 * Sridhar Samudrala <sri@us.ibm.com>
45 * Ardelle Fan <ardelle.fan@intel.com> 45 * Ardelle Fan <ardelle.fan@intel.com>
46 * 46 *
47 * Any bugs reported given to us we will try t 47 * Any bugs reported given to us we will try to fix... any fixes shared will
48 * be incorporated into the next SCTP release. 48 * be incorporated into the next SCTP release.
49 */ 49 */
50 50
51 #include <linux/types.h> 51 #include <linux/types.h>
52 #include <linux/list.h> /* For struct list_hea 52 #include <linux/list.h> /* For struct list_head */
53 #include <linux/socket.h> 53 #include <linux/socket.h>
54 #include <linux/ip.h> 54 #include <linux/ip.h>
55 #include <linux/time.h> /* For struct timeval 55 #include <linux/time.h> /* For struct timeval */
56 #include <net/ip.h> 56 #include <net/ip.h>
57 #include <net/icmp.h> 57 #include <net/icmp.h>
58 #include <net/snmp.h> 58 #include <net/snmp.h>
59 #include <net/sock.h> 59 #include <net/sock.h>
60 #include <net/xfrm.h> 60 #include <net/xfrm.h>
61 #include <net/sctp/sctp.h> 61 #include <net/sctp/sctp.h>
62 #include <net/sctp/sm.h> 62 #include <net/sctp/sm.h>
63 #include <net/sctp/checksum.h> <<
64 63
65 /* Forward declarations for internal helpers. 64 /* Forward declarations for internal helpers. */
66 static int sctp_rcv_ootb(struct sk_buff *); 65 static int sctp_rcv_ootb(struct sk_buff *);
67 static struct sctp_association *__sctp_rcv_loo 66 static struct sctp_association *__sctp_rcv_lookup(struct sk_buff *skb,
68 const un 67 const union sctp_addr *laddr,
69 const un 68 const union sctp_addr *paddr,
70 struct s 69 struct sctp_transport **transportp);
71 static struct sctp_endpoint *__sctp_rcv_lookup 70 static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *laddr);
72 static struct sctp_association *__sctp_lookup_ 71 static struct sctp_association *__sctp_lookup_association(
73 const 72 const union sctp_addr *local,
74 const 73 const union sctp_addr *peer,
75 struct 74 struct sctp_transport **pt);
76 75
77 static void sctp_add_backlog(struct sock *sk, <<
78 <<
79 76
80 /* Calculate the SCTP checksum of an SCTP pack 77 /* Calculate the SCTP checksum of an SCTP packet. */
81 static inline int sctp_rcv_checksum(struct sk_ 78 static inline int sctp_rcv_checksum(struct sk_buff *skb)
82 { 79 {
>> 80 struct sctphdr *sh;
>> 81 __u32 cmp, val;
83 struct sk_buff *list = skb_shinfo(skb) 82 struct sk_buff *list = skb_shinfo(skb)->frag_list;
84 struct sctphdr *sh = sctp_hdr(skb); !! 83
85 __u32 cmp = ntohl(sh->checksum); !! 84 sh = (struct sctphdr *) skb->h.raw;
86 __u32 val = sctp_start_cksum((__u8 *)s !! 85 cmp = ntohl(sh->checksum);
>> 86
>> 87 val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb));
87 88
88 for (; list; list = list->next) 89 for (; list; list = list->next)
89 val = sctp_update_cksum((__u8 90 val = sctp_update_cksum((__u8 *)list->data, skb_headlen(list),
90 val); 91 val);
91 92
92 val = sctp_end_cksum(val); 93 val = sctp_end_cksum(val);
93 94
94 if (val != cmp) { 95 if (val != cmp) {
95 /* CRC failure, dump it. */ 96 /* CRC failure, dump it. */
96 SCTP_INC_STATS_BH(SCTP_MIB_CHE 97 SCTP_INC_STATS_BH(SCTP_MIB_CHECKSUMERRORS);
97 return -1; 98 return -1;
98 } 99 }
99 return 0; 100 return 0;
100 } 101 }
101 102
102 struct sctp_input_cb { <<
103 union { <<
104 struct inet_skb_parm h4; <<
105 #if defined(CONFIG_IPV6) || defined (CONFIG_IP <<
106 struct inet6_skb_parm h6; <<
107 #endif <<
108 } header; <<
109 struct sctp_chunk *chunk; <<
110 }; <<
111 #define SCTP_INPUT_CB(__skb) ((struct sctp_ <<
112 <<
113 /* 103 /*
114 * This is the routine which IP calls when rec 104 * This is the routine which IP calls when receiving an SCTP packet.
115 */ 105 */
116 int sctp_rcv(struct sk_buff *skb) 106 int sctp_rcv(struct sk_buff *skb)
117 { 107 {
118 struct sock *sk; 108 struct sock *sk;
119 struct sctp_association *asoc; 109 struct sctp_association *asoc;
120 struct sctp_endpoint *ep = NULL; 110 struct sctp_endpoint *ep = NULL;
121 struct sctp_ep_common *rcvr; 111 struct sctp_ep_common *rcvr;
122 struct sctp_transport *transport = NUL 112 struct sctp_transport *transport = NULL;
123 struct sctp_chunk *chunk; 113 struct sctp_chunk *chunk;
124 struct sctphdr *sh; 114 struct sctphdr *sh;
125 union sctp_addr src; 115 union sctp_addr src;
126 union sctp_addr dest; 116 union sctp_addr dest;
127 int family; 117 int family;
128 struct sctp_af *af; 118 struct sctp_af *af;
>> 119 int ret = 0;
129 120
130 if (skb->pkt_type!=PACKET_HOST) 121 if (skb->pkt_type!=PACKET_HOST)
131 goto discard_it; 122 goto discard_it;
132 123
133 SCTP_INC_STATS_BH(SCTP_MIB_INSCTPPACKS 124 SCTP_INC_STATS_BH(SCTP_MIB_INSCTPPACKS);
134 125
135 if (skb_linearize(skb)) !! 126 sh = (struct sctphdr *) skb->h.raw;
136 goto discard_it; <<
137 <<
138 sh = sctp_hdr(skb); <<
139 127
140 /* Pull up the IP and SCTP headers. */ 128 /* Pull up the IP and SCTP headers. */
141 __skb_pull(skb, skb_transport_offset(s !! 129 __skb_pull(skb, skb->h.raw - skb->data);
142 if (skb->len < sizeof(struct sctphdr)) 130 if (skb->len < sizeof(struct sctphdr))
143 goto discard_it; 131 goto discard_it;
144 if (!skb_csum_unnecessary(skb) && sctp !! 132 if (sctp_rcv_checksum(skb) < 0)
145 goto discard_it; 133 goto discard_it;
146 134
147 skb_pull(skb, sizeof(struct sctphdr)); 135 skb_pull(skb, sizeof(struct sctphdr));
148 136
149 /* Make sure we at least have chunk he 137 /* Make sure we at least have chunk headers worth of data left. */
150 if (skb->len < sizeof(struct sctp_chun 138 if (skb->len < sizeof(struct sctp_chunkhdr))
151 goto discard_it; 139 goto discard_it;
152 140
153 family = ipver2af(ip_hdr(skb)->version !! 141 family = ipver2af(skb->nh.iph->version);
154 af = sctp_get_af_specific(family); 142 af = sctp_get_af_specific(family);
155 if (unlikely(!af)) 143 if (unlikely(!af))
156 goto discard_it; 144 goto discard_it;
157 145
158 /* Initialize local addresses for look 146 /* Initialize local addresses for lookups. */
159 af->from_skb(&src, skb, 1); 147 af->from_skb(&src, skb, 1);
160 af->from_skb(&dest, skb, 0); 148 af->from_skb(&dest, skb, 0);
161 149
162 /* If the packet is to or from a non-u 150 /* If the packet is to or from a non-unicast address,
163 * silently discard the packet. 151 * silently discard the packet.
164 * 152 *
165 * This is not clearly defined in the 153 * This is not clearly defined in the RFC except in section
166 * 8.4 - OOTB handling. However, base 154 * 8.4 - OOTB handling. However, based on the book "Stream Control
167 * Transmission Protocol" 2.1, "It is 155 * Transmission Protocol" 2.1, "It is important to note that the
168 * IP address of an SCTP transport add 156 * IP address of an SCTP transport address must be a routable
169 * unicast address. In other words, I 157 * unicast address. In other words, IP multicast addresses and
170 * IP broadcast addresses cannot be us 158 * IP broadcast addresses cannot be used in an SCTP transport
171 * address." 159 * address."
172 */ 160 */
173 if (!af->addr_valid(&src, NULL, skb) | !! 161 if (!af->addr_valid(&src, NULL) || !af->addr_valid(&dest, NULL))
174 !af->addr_valid(&dest, NULL, skb)) <<
175 goto discard_it; 162 goto discard_it;
176 163
177 asoc = __sctp_rcv_lookup(skb, &src, &d 164 asoc = __sctp_rcv_lookup(skb, &src, &dest, &transport);
178 165
179 if (!asoc) <<
180 ep = __sctp_rcv_lookup_endpoin <<
181 <<
182 /* Retrieve the common input handling <<
183 rcvr = asoc ? &asoc->base : &ep->base; <<
184 sk = rcvr->sk; <<
185 <<
186 /* <<
187 * If a frame arrives on an interface <<
188 * bound to another interface, via SO_ <<
189 */ <<
190 if (sk->sk_bound_dev_if && (sk->sk_bou <<
191 { <<
192 if (asoc) { <<
193 sctp_association_put(a <<
194 asoc = NULL; <<
195 } else { <<
196 sctp_endpoint_put(ep); <<
197 ep = NULL; <<
198 } <<
199 sk = sctp_get_ctl_sock(); <<
200 ep = sctp_sk(sk)->ep; <<
201 sctp_endpoint_hold(ep); <<
202 rcvr = &ep->base; <<
203 } <<
204 <<
205 /* 166 /*
206 * RFC 2960, 8.4 - Handle "Out of the 167 * RFC 2960, 8.4 - Handle "Out of the blue" Packets.
207 * An SCTP packet is called an "out of 168 * An SCTP packet is called an "out of the blue" (OOTB)
208 * packet if it is correctly formed, i 169 * packet if it is correctly formed, i.e., passed the
209 * receiver's checksum check, but the 170 * receiver's checksum check, but the receiver is not
210 * able to identify the association to 171 * able to identify the association to which this
211 * packet belongs. 172 * packet belongs.
212 */ 173 */
213 if (!asoc) { 174 if (!asoc) {
>> 175 ep = __sctp_rcv_lookup_endpoint(&dest);
214 if (sctp_rcv_ootb(skb)) { 176 if (sctp_rcv_ootb(skb)) {
215 SCTP_INC_STATS_BH(SCTP 177 SCTP_INC_STATS_BH(SCTP_MIB_OUTOFBLUES);
216 goto discard_release; 178 goto discard_release;
217 } 179 }
218 } 180 }
219 181
>> 182 /* Retrieve the common input handling substructure. */
>> 183 rcvr = asoc ? &asoc->base : &ep->base;
>> 184 sk = rcvr->sk;
>> 185
>> 186 /* SCTP seems to always need a timestamp right now (FIXME) */
>> 187 if (skb->stamp.tv_sec == 0) {
>> 188 do_gettimeofday(&skb->stamp);
>> 189 sock_enable_timestamp(sk);
>> 190 }
>> 191
220 if (!xfrm_policy_check(sk, XFRM_POLICY 192 if (!xfrm_policy_check(sk, XFRM_POLICY_IN, skb, family))
221 goto discard_release; 193 goto discard_release;
222 nf_reset(skb); <<
223 194
224 if (sk_filter(sk, skb)) !! 195 ret = sk_filter(sk, skb, 1);
225 goto discard_release; !! 196 if (ret)
>> 197 goto discard_release;
226 198
227 /* Create an SCTP packet structure. */ 199 /* Create an SCTP packet structure. */
228 chunk = sctp_chunkify(skb, asoc, sk); 200 chunk = sctp_chunkify(skb, asoc, sk);
229 if (!chunk) !! 201 if (!chunk) {
>> 202 ret = -ENOMEM;
230 goto discard_release; 203 goto discard_release;
231 SCTP_INPUT_CB(skb)->chunk = chunk; !! 204 }
232 205
233 /* Remember what endpoint is to handle 206 /* Remember what endpoint is to handle this packet. */
234 chunk->rcvr = rcvr; 207 chunk->rcvr = rcvr;
235 208
236 /* Remember the SCTP header. */ 209 /* Remember the SCTP header. */
237 chunk->sctp_hdr = sh; 210 chunk->sctp_hdr = sh;
238 211
239 /* Set the source and destination addr 212 /* Set the source and destination addresses of the incoming chunk. */
240 sctp_init_addrs(chunk, &src, &dest); 213 sctp_init_addrs(chunk, &src, &dest);
241 214
242 /* Remember where we came from. */ 215 /* Remember where we came from. */
243 chunk->transport = transport; 216 chunk->transport = transport;
244 217
245 /* Acquire access to the sock lock. No 218 /* Acquire access to the sock lock. Note: We are safe from other
246 * bottom halves on this lock, but a u 219 * bottom halves on this lock, but a user may be in the lock too,
247 * so check if it is busy. 220 * so check if it is busy.
248 */ 221 */
249 sctp_bh_lock_sock(sk); 222 sctp_bh_lock_sock(sk);
250 223
251 if (sock_owned_by_user(sk)) { !! 224 if (sock_owned_by_user(sk))
252 SCTP_INC_STATS_BH(SCTP_MIB_IN_ !! 225 sk_add_backlog(sk, (struct sk_buff *) chunk);
253 sctp_add_backlog(sk, skb); !! 226 else
254 } else { !! 227 sctp_backlog_rcv(sk, (struct sk_buff *) chunk);
255 SCTP_INC_STATS_BH(SCTP_MIB_IN_ <<
256 sctp_inq_push(&chunk->rcvr->in <<
257 } <<
258 228
>> 229 /* Release the sock and any reference counts we took in the
>> 230 * lookup calls.
>> 231 */
259 sctp_bh_unlock_sock(sk); 232 sctp_bh_unlock_sock(sk);
260 <<
261 /* Release the asoc/ep ref we took in <<
262 if (asoc) 233 if (asoc)
263 sctp_association_put(asoc); 234 sctp_association_put(asoc);
264 else 235 else
265 sctp_endpoint_put(ep); 236 sctp_endpoint_put(ep);
266 !! 237 sock_put(sk);
267 return 0; !! 238 return ret;
268 239
269 discard_it: 240 discard_it:
270 SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_DISC <<
271 kfree_skb(skb); 241 kfree_skb(skb);
272 return 0; !! 242 return ret;
273 243
274 discard_release: 244 discard_release:
275 /* Release the asoc/ep ref we took in !! 245 /* Release any structures we may be holding. */
276 if (asoc) !! 246 if (asoc) {
>> 247 sock_put(asoc->base.sk);
277 sctp_association_put(asoc); 248 sctp_association_put(asoc);
278 else !! 249 } else {
>> 250 sock_put(ep->base.sk);
279 sctp_endpoint_put(ep); 251 sctp_endpoint_put(ep);
>> 252 }
280 253
281 goto discard_it; 254 goto discard_it;
282 } 255 }
283 256
284 /* Process the backlog queue of the socket. E !! 257 /* Handle second half of inbound skb processing. If the sock was busy,
285 * the backlog holds a ref on an association o !! 258 * we may have need to delay processing until later when the sock is
286 * We hold this ref throughout the state machi !! 259 * released (on the backlog). If not busy, we call this routine
287 * sure that the structure we need is still ar !! 260 * directly from the bottom half.
288 */ 261 */
289 int sctp_backlog_rcv(struct sock *sk, struct s 262 int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb)
290 { 263 {
291 struct sctp_chunk *chunk = SCTP_INPUT_ !! 264 struct sctp_chunk *chunk;
292 struct sctp_inq *inqueue = &chunk->rcv !! 265 struct sctp_inq *inqueue;
293 struct sctp_ep_common *rcvr = NULL; <<
294 int backloged = 0; <<
295 <<
296 rcvr = chunk->rcvr; <<
297 <<
298 /* If the rcvr is dead then the associ <<
299 * has been deleted and we can safely <<
300 * and refs that we are holding. <<
301 */ <<
302 if (rcvr->dead) { <<
303 sctp_chunk_free(chunk); <<
304 goto done; <<
305 } <<
306 <<
307 if (unlikely(rcvr->sk != sk)) { <<
308 /* In this case, the associati <<
309 * another. We are currently <<
310 * old socket, so we need to m <<
311 * However, since we are here <<
312 * need to take make sure that <<
313 * the new socket when we proc <<
314 * If the new socket is user-o <<
315 * backlog of the new socket w <<
316 * Otherwise, we can safely pu <<
317 */ <<
318 <<
319 sk = rcvr->sk; <<
320 sctp_bh_lock_sock(sk); <<
321 <<
322 if (sock_owned_by_user(sk)) { <<
323 sk_add_backlog(sk, skb <<
324 backloged = 1; <<
325 } else <<
326 sctp_inq_push(inqueue, <<
327 <<
328 sctp_bh_unlock_sock(sk); <<
329 <<
330 /* If the chunk was backloged <<
331 if (backloged) <<
332 return 0; <<
333 } else { <<
334 sctp_inq_push(inqueue, chunk); <<
335 } <<
336 <<
337 done: <<
338 /* Release the refs we took in sctp_ad <<
339 if (SCTP_EP_TYPE_ASSOCIATION == rcvr-> <<
340 sctp_association_put(sctp_asso <<
341 else if (SCTP_EP_TYPE_SOCKET == rcvr-> <<
342 sctp_endpoint_put(sctp_ep(rcvr <<
343 else <<
344 BUG(); <<
345 <<
346 return 0; <<
347 } <<
348 <<
349 static void sctp_add_backlog(struct sock *sk, <<
350 { <<
351 struct sctp_chunk *chunk = SCTP_INPUT_ <<
352 struct sctp_ep_common *rcvr = chunk->r <<
353 266
354 /* Hold the assoc/ep while hanging on !! 267 /* One day chunk will live inside the skb, but for
355 * This way, we know structures we nee !! 268 * now this works.
356 */ 269 */
357 if (SCTP_EP_TYPE_ASSOCIATION == rcvr-> !! 270 chunk = (struct sctp_chunk *) skb;
358 sctp_association_hold(sctp_ass !! 271 inqueue = &chunk->rcvr->inqueue;
359 else if (SCTP_EP_TYPE_SOCKET == rcvr-> <<
360 sctp_endpoint_hold(sctp_ep(rcv <<
361 else <<
362 BUG(); <<
363 272
364 sk_add_backlog(sk, skb); !! 273 sctp_inq_push(inqueue, chunk);
>> 274 return 0;
365 } 275 }
366 276
367 /* Handle icmp frag needed error. */ 277 /* Handle icmp frag needed error. */
368 void sctp_icmp_frag_needed(struct sock *sk, st 278 void sctp_icmp_frag_needed(struct sock *sk, struct sctp_association *asoc,
369 struct sctp_transpo 279 struct sctp_transport *t, __u32 pmtu)
370 { 280 {
371 if (!t || (t->pathmtu == pmtu)) !! 281 if (unlikely(pmtu < SCTP_DEFAULT_MINSEGMENT)) {
372 return; !! 282 printk(KERN_WARNING "%s: Reported pmtu %d too low, "
373 !! 283 "using default minimum of %d\n", __FUNCTION__, pmtu,
374 if (sock_owned_by_user(sk)) { !! 284 SCTP_DEFAULT_MINSEGMENT);
375 asoc->pmtu_pending = 1; !! 285 pmtu = SCTP_DEFAULT_MINSEGMENT;
376 t->pmtu_pending = 1; <<
377 return; <<
378 } 286 }
379 287
380 if (t->param_flags & SPP_PMTUD_ENABLE) !! 288 if (!sock_owned_by_user(sk) && t && (t->pmtu != pmtu)) {
381 /* Update transports view of t !! 289 t->pmtu = pmtu;
382 sctp_transport_update_pmtu(t, <<
383 <<
384 /* Update association pmtu. */ <<
385 sctp_assoc_sync_pmtu(asoc); 290 sctp_assoc_sync_pmtu(asoc);
>> 291 sctp_retransmit(&asoc->outqueue, t, SCTP_RTXR_PMTUD);
386 } 292 }
387 <<
388 /* Retransmit with the new pmtu settin <<
389 * Normally, if PMTU discovery is disa <<
390 * Needed will never be sent, but if a <<
391 * PMTU discovery was disabled that wa <<
392 * would not be fragmented, so it must <<
393 */ <<
394 sctp_retransmit(&asoc->outqueue, t, SC <<
395 } 293 }
396 294
397 /* 295 /*
398 * SCTP Implementer's Guide, 2.37 ICMP handlin 296 * SCTP Implementer's Guide, 2.37 ICMP handling procedures
399 * 297 *
400 * ICMP8) If the ICMP code is a "Unrecognized 298 * ICMP8) If the ICMP code is a "Unrecognized next header type encountered"
401 * or a "Protocol Unreachable" treat th 299 * or a "Protocol Unreachable" treat this message as an abort
402 * with the T bit set. 300 * with the T bit set.
403 * 301 *
404 * This function sends an event to the state m 302 * This function sends an event to the state machine, which will abort the
405 * association. 303 * association.
406 * 304 *
407 */ 305 */
408 void sctp_icmp_proto_unreachable(struct sock * 306 void sctp_icmp_proto_unreachable(struct sock *sk,
409 struct sctp_associa !! 307 struct sctp_endpoint *ep,
410 struct sctp_transpo !! 308 struct sctp_association *asoc,
>> 309 struct sctp_transport *t)
411 { 310 {
412 SCTP_DEBUG_PRINTK("%s\n", __FUNCTION_ 311 SCTP_DEBUG_PRINTK("%s\n", __FUNCTION__);
413 312
414 sctp_do_sm(SCTP_EVENT_T_OTHER, 313 sctp_do_sm(SCTP_EVENT_T_OTHER,
415 SCTP_ST_OTHER(SCTP_EVENT_IC 314 SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH),
416 asoc->state, asoc->ep, asoc !! 315 asoc->state, asoc->ep, asoc, NULL,
417 GFP_ATOMIC); 316 GFP_ATOMIC);
418 317
419 } 318 }
420 319
421 /* Common lookup code for icmp/icmpv6 error ha 320 /* Common lookup code for icmp/icmpv6 error handler. */
422 struct sock *sctp_err_lookup(int family, struc 321 struct sock *sctp_err_lookup(int family, struct sk_buff *skb,
423 struct sctphdr *s 322 struct sctphdr *sctphdr,
>> 323 struct sctp_endpoint **epp,
424 struct sctp_assoc 324 struct sctp_association **app,
425 struct sctp_trans 325 struct sctp_transport **tpp)
426 { 326 {
427 union sctp_addr saddr; 327 union sctp_addr saddr;
428 union sctp_addr daddr; 328 union sctp_addr daddr;
429 struct sctp_af *af; 329 struct sctp_af *af;
430 struct sock *sk = NULL; 330 struct sock *sk = NULL;
431 struct sctp_association *asoc; !! 331 struct sctp_endpoint *ep = NULL;
>> 332 struct sctp_association *asoc = NULL;
432 struct sctp_transport *transport = NUL 333 struct sctp_transport *transport = NULL;
433 334
434 *app = NULL; *tpp = NULL; !! 335 *app = NULL; *epp = NULL; *tpp = NULL;
435 336
436 af = sctp_get_af_specific(family); 337 af = sctp_get_af_specific(family);
437 if (unlikely(!af)) { 338 if (unlikely(!af)) {
438 return NULL; 339 return NULL;
439 } 340 }
440 341
441 /* Initialize local addresses for look 342 /* Initialize local addresses for lookups. */
442 af->from_skb(&saddr, skb, 1); 343 af->from_skb(&saddr, skb, 1);
443 af->from_skb(&daddr, skb, 0); 344 af->from_skb(&daddr, skb, 0);
444 345
445 /* Look for an association that matche 346 /* Look for an association that matches the incoming ICMP error
446 * packet. 347 * packet.
447 */ 348 */
448 asoc = __sctp_lookup_association(&sadd 349 asoc = __sctp_lookup_association(&saddr, &daddr, &transport);
449 if (!asoc) !! 350 if (!asoc) {
450 return NULL; !! 351 /* If there is no matching association, see if it matches any
>> 352 * endpoint. This may happen for an ICMP error generated in
>> 353 * response to an INIT_ACK.
>> 354 */
>> 355 ep = __sctp_rcv_lookup_endpoint(&daddr);
>> 356 if (!ep) {
>> 357 return NULL;
>> 358 }
>> 359 }
451 360
452 sk = asoc->base.sk; !! 361 if (asoc) {
>> 362 sk = asoc->base.sk;
453 363
454 if (ntohl(sctphdr->vtag) != asoc->c.pe !! 364 if (ntohl(sctphdr->vtag) != asoc->c.peer_vtag) {
455 ICMP_INC_STATS_BH(ICMP_MIB_INE !! 365 ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
456 goto out; !! 366 goto out;
457 } !! 367 }
>> 368 } else
>> 369 sk = ep->base.sk;
458 370
459 sctp_bh_lock_sock(sk); 371 sctp_bh_lock_sock(sk);
460 372
461 /* If too many ICMPs get dropped on bu 373 /* If too many ICMPs get dropped on busy
462 * servers this needs to be solved dif 374 * servers this needs to be solved differently.
463 */ 375 */
464 if (sock_owned_by_user(sk)) 376 if (sock_owned_by_user(sk))
465 NET_INC_STATS_BH(LINUX_MIB_LOC 377 NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);
466 378
>> 379 *epp = ep;
467 *app = asoc; 380 *app = asoc;
468 *tpp = transport; 381 *tpp = transport;
469 return sk; 382 return sk;
470 383
471 out: 384 out:
>> 385 sock_put(sk);
472 if (asoc) 386 if (asoc)
473 sctp_association_put(asoc); 387 sctp_association_put(asoc);
>> 388 if (ep)
>> 389 sctp_endpoint_put(ep);
474 return NULL; 390 return NULL;
475 } 391 }
476 392
477 /* Common cleanup code for icmp/icmpv6 error h 393 /* Common cleanup code for icmp/icmpv6 error handler. */
478 void sctp_err_finish(struct sock *sk, struct s !! 394 void sctp_err_finish(struct sock *sk, struct sctp_endpoint *ep,
>> 395 struct sctp_association *asoc)
479 { 396 {
480 sctp_bh_unlock_sock(sk); 397 sctp_bh_unlock_sock(sk);
>> 398 sock_put(sk);
481 if (asoc) 399 if (asoc)
482 sctp_association_put(asoc); 400 sctp_association_put(asoc);
>> 401 if (ep)
>> 402 sctp_endpoint_put(ep);
483 } 403 }
484 404
485 /* 405 /*
486 * This routine is called by the ICMP module w 406 * This routine is called by the ICMP module when it gets some
487 * sort of error condition. If err < 0 then t 407 * sort of error condition. If err < 0 then the socket should
488 * be closed and the error returned to the use 408 * be closed and the error returned to the user. If err > 0
489 * it's just the icmp type << 8 | icmp code. 409 * it's just the icmp type << 8 | icmp code. After adjustment
490 * header points to the first 8 bytes of the s 410 * header points to the first 8 bytes of the sctp header. We need
491 * to find the appropriate port. 411 * to find the appropriate port.
492 * 412 *
493 * The locking strategy used here is very "opt 413 * The locking strategy used here is very "optimistic". When
494 * someone else accesses the socket the ICMP i 414 * someone else accesses the socket the ICMP is just dropped
495 * and for some paths there is no check at all 415 * and for some paths there is no check at all.
496 * A more general error queue to queue errors 416 * A more general error queue to queue errors for later handling
497 * is probably better. 417 * is probably better.
498 * 418 *
499 */ 419 */
500 void sctp_v4_err(struct sk_buff *skb, __u32 in 420 void sctp_v4_err(struct sk_buff *skb, __u32 info)
501 { 421 {
502 struct iphdr *iph = (struct iphdr *)sk 422 struct iphdr *iph = (struct iphdr *)skb->data;
503 const int ihlen = iph->ihl * 4; !! 423 struct sctphdr *sh = (struct sctphdr *)(skb->data + (iph->ihl <<2));
504 const int type = icmp_hdr(skb)->type; !! 424 int type = skb->h.icmph->type;
505 const int code = icmp_hdr(skb)->code; !! 425 int code = skb->h.icmph->code;
506 struct sock *sk; 426 struct sock *sk;
507 struct sctp_association *asoc = NULL; !! 427 struct sctp_endpoint *ep;
>> 428 struct sctp_association *asoc;
508 struct sctp_transport *transport; 429 struct sctp_transport *transport;
509 struct inet_sock *inet; 430 struct inet_sock *inet;
510 sk_buff_data_t saveip, savesctp; !! 431 char *saveip, *savesctp;
511 int err; 432 int err;
512 433
513 if (skb->len < ihlen + 8) { !! 434 if (skb->len < ((iph->ihl << 2) + 8)) {
514 ICMP_INC_STATS_BH(ICMP_MIB_INE 435 ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
515 return; 436 return;
516 } 437 }
517 438
518 /* Fix up skb to look at the embedded 439 /* Fix up skb to look at the embedded net header. */
519 saveip = skb->network_header; !! 440 saveip = skb->nh.raw;
520 savesctp = skb->transport_header; !! 441 savesctp = skb->h.raw;
521 skb_reset_network_header(skb); !! 442 skb->nh.iph = iph;
522 skb_set_transport_header(skb, ihlen); !! 443 skb->h.raw = (char *)sh;
523 sk = sctp_err_lookup(AF_INET, skb, sct !! 444 sk = sctp_err_lookup(AF_INET, skb, sh, &ep, &asoc, &transport);
524 /* Put back, the original values. */ !! 445 /* Put back, the original pointers. */
525 skb->network_header = saveip; !! 446 skb->nh.raw = saveip;
526 skb->transport_header = savesctp; !! 447 skb->h.raw = savesctp;
527 if (!sk) { 448 if (!sk) {
528 ICMP_INC_STATS_BH(ICMP_MIB_INE 449 ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
529 return; 450 return;
530 } 451 }
531 /* Warning: The sock lock is held. R 452 /* Warning: The sock lock is held. Remember to call
532 * sctp_err_finish! 453 * sctp_err_finish!
533 */ 454 */
534 455
535 switch (type) { 456 switch (type) {
536 case ICMP_PARAMETERPROB: 457 case ICMP_PARAMETERPROB:
537 err = EPROTO; 458 err = EPROTO;
538 break; 459 break;
539 case ICMP_DEST_UNREACH: 460 case ICMP_DEST_UNREACH:
540 if (code > NR_ICMP_UNREACH) 461 if (code > NR_ICMP_UNREACH)
541 goto out_unlock; 462 goto out_unlock;
542 463
543 /* PMTU discovery (RFC1191) */ 464 /* PMTU discovery (RFC1191) */
544 if (ICMP_FRAG_NEEDED == code) 465 if (ICMP_FRAG_NEEDED == code) {
545 sctp_icmp_frag_needed( 466 sctp_icmp_frag_needed(sk, asoc, transport, info);
546 goto out_unlock; 467 goto out_unlock;
547 } 468 }
548 else { 469 else {
549 if (ICMP_PROT_UNREACH 470 if (ICMP_PROT_UNREACH == code) {
550 sctp_icmp_prot !! 471 sctp_icmp_proto_unreachable(sk, ep, asoc,
551 472 transport);
552 goto out_unloc 473 goto out_unlock;
553 } 474 }
554 } 475 }
555 err = icmp_err_convert[code].e 476 err = icmp_err_convert[code].errno;
556 break; 477 break;
557 case ICMP_TIME_EXCEEDED: 478 case ICMP_TIME_EXCEEDED:
558 /* Ignore any time exceeded er 479 /* Ignore any time exceeded errors due to fragment reassembly
559 * timeouts. 480 * timeouts.
560 */ 481 */
561 if (ICMP_EXC_FRAGTIME == code) 482 if (ICMP_EXC_FRAGTIME == code)
562 goto out_unlock; 483 goto out_unlock;
563 484
564 err = EHOSTUNREACH; 485 err = EHOSTUNREACH;
565 break; 486 break;
566 default: 487 default:
567 goto out_unlock; 488 goto out_unlock;
568 } 489 }
569 490
570 inet = inet_sk(sk); 491 inet = inet_sk(sk);
571 if (!sock_owned_by_user(sk) && inet->r 492 if (!sock_owned_by_user(sk) && inet->recverr) {
572 sk->sk_err = err; 493 sk->sk_err = err;
573 sk->sk_error_report(sk); 494 sk->sk_error_report(sk);
574 } else { /* Only an error on timeout 495 } else { /* Only an error on timeout */
575 sk->sk_err_soft = err; 496 sk->sk_err_soft = err;
576 } 497 }
577 498
578 out_unlock: 499 out_unlock:
579 sctp_err_finish(sk, asoc); !! 500 sctp_err_finish(sk, ep, asoc);
580 } 501 }
581 502
582 /* 503 /*
583 * RFC 2960, 8.4 - Handle "Out of the blue" Pa 504 * RFC 2960, 8.4 - Handle "Out of the blue" Packets.
584 * 505 *
585 * This function scans all the chunks in the O 506 * This function scans all the chunks in the OOTB packet to determine if
586 * the packet should be discarded right away. 507 * the packet should be discarded right away. If a response might be needed
587 * for this packet, or, if further processing 508 * for this packet, or, if further processing is possible, the packet will
588 * be queued to a proper inqueue for the next 509 * be queued to a proper inqueue for the next phase of handling.
589 * 510 *
590 * Output: 511 * Output:
591 * Return 0 - If further processing is needed. 512 * Return 0 - If further processing is needed.
592 * Return 1 - If the packet can be discarded r 513 * Return 1 - If the packet can be discarded right away.
593 */ 514 */
594 static int sctp_rcv_ootb(struct sk_buff *skb) !! 515 int sctp_rcv_ootb(struct sk_buff *skb)
595 { 516 {
596 sctp_chunkhdr_t *ch; 517 sctp_chunkhdr_t *ch;
597 __u8 *ch_end; 518 __u8 *ch_end;
598 sctp_errhdr_t *err; 519 sctp_errhdr_t *err;
599 520
600 ch = (sctp_chunkhdr_t *) skb->data; 521 ch = (sctp_chunkhdr_t *) skb->data;
>> 522 ch_end = ((__u8 *) ch) + WORD_ROUND(ntohs(ch->length));
601 523
602 /* Scan through all the chunks in the 524 /* Scan through all the chunks in the packet. */
603 do { !! 525 while (ch_end > (__u8 *)ch && ch_end < skb->tail) {
604 /* Break out if chunk length i <<
605 if (ntohs(ch->length) < sizeof <<
606 break; <<
607 <<
608 ch_end = ((__u8 *)ch) + WORD_R <<
609 if (ch_end > skb_tail_pointer( <<
610 break; <<
611 526
612 /* RFC 8.4, 2) If the OOTB pac 527 /* RFC 8.4, 2) If the OOTB packet contains an ABORT chunk, the
613 * receiver MUST silently disc 528 * receiver MUST silently discard the OOTB packet and take no
614 * further action. 529 * further action.
615 */ 530 */
616 if (SCTP_CID_ABORT == ch->type 531 if (SCTP_CID_ABORT == ch->type)
617 goto discard; 532 goto discard;
618 533
619 /* RFC 8.4, 6) If the packet c 534 /* RFC 8.4, 6) If the packet contains a SHUTDOWN COMPLETE
620 * chunk, the receiver should 535 * chunk, the receiver should silently discard the packet
621 * and take no further action. 536 * and take no further action.
622 */ 537 */
623 if (SCTP_CID_SHUTDOWN_COMPLETE 538 if (SCTP_CID_SHUTDOWN_COMPLETE == ch->type)
624 goto discard; 539 goto discard;
625 540
626 /* RFC 4460, 2.11.2 <<
627 * This will discard packets w <<
628 * subsequent chunks in the pa <<
629 * the normal INIT processing <<
630 */ <<
631 if (SCTP_CID_INIT == ch->type <<
632 goto discard; <<
633 <<
634 /* RFC 8.4, 7) If the packet c 541 /* RFC 8.4, 7) If the packet contains a "Stale cookie" ERROR
635 * or a COOKIE ACK the SCTP Pa 542 * or a COOKIE ACK the SCTP Packet should be silently
636 * discarded. 543 * discarded.
637 */ 544 */
638 if (SCTP_CID_COOKIE_ACK == ch- 545 if (SCTP_CID_COOKIE_ACK == ch->type)
639 goto discard; 546 goto discard;
640 547
641 if (SCTP_CID_ERROR == ch->type 548 if (SCTP_CID_ERROR == ch->type) {
642 sctp_walk_errors(err, 549 sctp_walk_errors(err, ch) {
643 if (SCTP_ERROR 550 if (SCTP_ERROR_STALE_COOKIE == err->cause)
644 goto d 551 goto discard;
645 } 552 }
646 } 553 }
647 554
648 ch = (sctp_chunkhdr_t *) ch_en 555 ch = (sctp_chunkhdr_t *) ch_end;
649 } while (ch_end < skb_tail_pointer(skb !! 556 ch_end = ((__u8 *) ch) + WORD_ROUND(ntohs(ch->length));
>> 557 }
650 558
651 return 0; 559 return 0;
652 560
653 discard: 561 discard:
654 return 1; 562 return 1;
655 } 563 }
656 564
657 /* Insert endpoint into the hash table. */ 565 /* Insert endpoint into the hash table. */
658 static void __sctp_hash_endpoint(struct sctp_e 566 static void __sctp_hash_endpoint(struct sctp_endpoint *ep)
659 { 567 {
>> 568 struct sctp_ep_common **epp;
660 struct sctp_ep_common *epb; 569 struct sctp_ep_common *epb;
661 struct sctp_hashbucket *head; 570 struct sctp_hashbucket *head;
662 571
663 epb = &ep->base; 572 epb = &ep->base;
664 573
665 epb->hashent = sctp_ep_hashfn(epb->bin 574 epb->hashent = sctp_ep_hashfn(epb->bind_addr.port);
666 head = &sctp_ep_hashtable[epb->hashent 575 head = &sctp_ep_hashtable[epb->hashent];
667 576
668 sctp_write_lock(&head->lock); 577 sctp_write_lock(&head->lock);
669 hlist_add_head(&epb->node, &head->chai !! 578 epp = &head->chain;
>> 579 epb->next = *epp;
>> 580 if (epb->next)
>> 581 (*epp)->pprev = &epb->next;
>> 582 *epp = epb;
>> 583 epb->pprev = epp;
670 sctp_write_unlock(&head->lock); 584 sctp_write_unlock(&head->lock);
671 } 585 }
672 586
673 /* Add an endpoint to the hash. Local BH-safe. 587 /* Add an endpoint to the hash. Local BH-safe. */
674 void sctp_hash_endpoint(struct sctp_endpoint * 588 void sctp_hash_endpoint(struct sctp_endpoint *ep)
675 { 589 {
676 sctp_local_bh_disable(); 590 sctp_local_bh_disable();
677 __sctp_hash_endpoint(ep); 591 __sctp_hash_endpoint(ep);
678 sctp_local_bh_enable(); 592 sctp_local_bh_enable();
679 } 593 }
680 594
681 /* Remove endpoint from the hash table. */ 595 /* Remove endpoint from the hash table. */
682 static void __sctp_unhash_endpoint(struct sctp 596 static void __sctp_unhash_endpoint(struct sctp_endpoint *ep)
683 { 597 {
684 struct sctp_hashbucket *head; 598 struct sctp_hashbucket *head;
685 struct sctp_ep_common *epb; 599 struct sctp_ep_common *epb;
686 600
687 epb = &ep->base; 601 epb = &ep->base;
688 602
689 if (hlist_unhashed(&epb->node)) <<
690 return; <<
691 <<
692 epb->hashent = sctp_ep_hashfn(epb->bin 603 epb->hashent = sctp_ep_hashfn(epb->bind_addr.port);
693 604
694 head = &sctp_ep_hashtable[epb->hashent 605 head = &sctp_ep_hashtable[epb->hashent];
695 606
696 sctp_write_lock(&head->lock); 607 sctp_write_lock(&head->lock);
697 __hlist_del(&epb->node); !! 608
>> 609 if (epb->pprev) {
>> 610 if (epb->next)
>> 611 epb->next->pprev = epb->pprev;
>> 612 *epb->pprev = epb->next;
>> 613 epb->pprev = NULL;
>> 614 }
>> 615
698 sctp_write_unlock(&head->lock); 616 sctp_write_unlock(&head->lock);
699 } 617 }
700 618
701 /* Remove endpoint from the hash. Local BH-sa 619 /* Remove endpoint from the hash. Local BH-safe. */
702 void sctp_unhash_endpoint(struct sctp_endpoint 620 void sctp_unhash_endpoint(struct sctp_endpoint *ep)
703 { 621 {
704 sctp_local_bh_disable(); 622 sctp_local_bh_disable();
705 __sctp_unhash_endpoint(ep); 623 __sctp_unhash_endpoint(ep);
706 sctp_local_bh_enable(); 624 sctp_local_bh_enable();
707 } 625 }
708 626
709 /* Look up an endpoint. */ 627 /* Look up an endpoint. */
710 static struct sctp_endpoint *__sctp_rcv_lookup 628 static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *laddr)
711 { 629 {
712 struct sctp_hashbucket *head; 630 struct sctp_hashbucket *head;
713 struct sctp_ep_common *epb; 631 struct sctp_ep_common *epb;
714 struct sctp_endpoint *ep; 632 struct sctp_endpoint *ep;
715 struct hlist_node *node; <<
716 int hash; 633 int hash;
717 634
718 hash = sctp_ep_hashfn(ntohs(laddr->v4. !! 635 hash = sctp_ep_hashfn(laddr->v4.sin_port);
719 head = &sctp_ep_hashtable[hash]; 636 head = &sctp_ep_hashtable[hash];
720 read_lock(&head->lock); 637 read_lock(&head->lock);
721 sctp_for_each_hentry(epb, node, &head- !! 638 for (epb = head->chain; epb; epb = epb->next) {
722 ep = sctp_ep(epb); 639 ep = sctp_ep(epb);
723 if (sctp_endpoint_is_match(ep, 640 if (sctp_endpoint_is_match(ep, laddr))
724 goto hit; 641 goto hit;
725 } 642 }
726 643
727 ep = sctp_sk((sctp_get_ctl_sock()))->e 644 ep = sctp_sk((sctp_get_ctl_sock()))->ep;
728 epb = &ep->base; 645 epb = &ep->base;
729 646
730 hit: 647 hit:
731 sctp_endpoint_hold(ep); 648 sctp_endpoint_hold(ep);
>> 649 sock_hold(epb->sk);
732 read_unlock(&head->lock); 650 read_unlock(&head->lock);
733 return ep; 651 return ep;
734 } 652 }
735 653
736 /* Insert association into the hash table. */ 654 /* Insert association into the hash table. */
737 static void __sctp_hash_established(struct sct 655 static void __sctp_hash_established(struct sctp_association *asoc)
738 { 656 {
>> 657 struct sctp_ep_common **epp;
739 struct sctp_ep_common *epb; 658 struct sctp_ep_common *epb;
740 struct sctp_hashbucket *head; 659 struct sctp_hashbucket *head;
741 660
742 epb = &asoc->base; 661 epb = &asoc->base;
743 662
744 /* Calculate which chain this entry wi 663 /* Calculate which chain this entry will belong to. */
745 epb->hashent = sctp_assoc_hashfn(epb-> 664 epb->hashent = sctp_assoc_hashfn(epb->bind_addr.port, asoc->peer.port);
746 665
747 head = &sctp_assoc_hashtable[epb->hash 666 head = &sctp_assoc_hashtable[epb->hashent];
748 667
749 sctp_write_lock(&head->lock); 668 sctp_write_lock(&head->lock);
750 hlist_add_head(&epb->node, &head->chai !! 669 epp = &head->chain;
>> 670 epb->next = *epp;
>> 671 if (epb->next)
>> 672 (*epp)->pprev = &epb->next;
>> 673 *epp = epb;
>> 674 epb->pprev = epp;
751 sctp_write_unlock(&head->lock); 675 sctp_write_unlock(&head->lock);
752 } 676 }
753 677
754 /* Add an association to the hash. Local BH-sa 678 /* Add an association to the hash. Local BH-safe. */
755 void sctp_hash_established(struct sctp_associa 679 void sctp_hash_established(struct sctp_association *asoc)
756 { 680 {
757 if (asoc->temp) <<
758 return; <<
759 <<
760 sctp_local_bh_disable(); 681 sctp_local_bh_disable();
761 __sctp_hash_established(asoc); 682 __sctp_hash_established(asoc);
762 sctp_local_bh_enable(); 683 sctp_local_bh_enable();
763 } 684 }
764 685
765 /* Remove association from the hash table. */ 686 /* Remove association from the hash table. */
766 static void __sctp_unhash_established(struct s 687 static void __sctp_unhash_established(struct sctp_association *asoc)
767 { 688 {
768 struct sctp_hashbucket *head; 689 struct sctp_hashbucket *head;
769 struct sctp_ep_common *epb; 690 struct sctp_ep_common *epb;
770 691
771 epb = &asoc->base; 692 epb = &asoc->base;
772 693
773 epb->hashent = sctp_assoc_hashfn(epb-> 694 epb->hashent = sctp_assoc_hashfn(epb->bind_addr.port,
774 asoc- 695 asoc->peer.port);
775 696
776 head = &sctp_assoc_hashtable[epb->hash 697 head = &sctp_assoc_hashtable[epb->hashent];
777 698
778 sctp_write_lock(&head->lock); 699 sctp_write_lock(&head->lock);
779 __hlist_del(&epb->node); !! 700
>> 701 if (epb->pprev) {
>> 702 if (epb->next)
>> 703 epb->next->pprev = epb->pprev;
>> 704 *epb->pprev = epb->next;
>> 705 epb->pprev = NULL;
>> 706 }
>> 707
780 sctp_write_unlock(&head->lock); 708 sctp_write_unlock(&head->lock);
781 } 709 }
782 710
783 /* Remove association from the hash table. Lo 711 /* Remove association from the hash table. Local BH-safe. */
784 void sctp_unhash_established(struct sctp_assoc 712 void sctp_unhash_established(struct sctp_association *asoc)
785 { 713 {
786 if (asoc->temp) <<
787 return; <<
788 <<
789 sctp_local_bh_disable(); 714 sctp_local_bh_disable();
790 __sctp_unhash_established(asoc); 715 __sctp_unhash_established(asoc);
791 sctp_local_bh_enable(); 716 sctp_local_bh_enable();
792 } 717 }
793 718
794 /* Look up an association. */ 719 /* Look up an association. */
795 static struct sctp_association *__sctp_lookup_ 720 static struct sctp_association *__sctp_lookup_association(
796 const 721 const union sctp_addr *local,
797 const 722 const union sctp_addr *peer,
798 struct 723 struct sctp_transport **pt)
799 { 724 {
800 struct sctp_hashbucket *head; 725 struct sctp_hashbucket *head;
801 struct sctp_ep_common *epb; 726 struct sctp_ep_common *epb;
802 struct sctp_association *asoc; 727 struct sctp_association *asoc;
803 struct sctp_transport *transport; 728 struct sctp_transport *transport;
804 struct hlist_node *node; <<
805 int hash; 729 int hash;
806 730
807 /* Optimize here for direct hit, only 731 /* Optimize here for direct hit, only listening connections can
808 * have wildcards anyways. 732 * have wildcards anyways.
809 */ 733 */
810 hash = sctp_assoc_hashfn(ntohs(local-> !! 734 hash = sctp_assoc_hashfn(local->v4.sin_port, peer->v4.sin_port);
811 head = &sctp_assoc_hashtable[hash]; 735 head = &sctp_assoc_hashtable[hash];
812 read_lock(&head->lock); 736 read_lock(&head->lock);
813 sctp_for_each_hentry(epb, node, &head- !! 737 for (epb = head->chain; epb; epb = epb->next) {
814 asoc = sctp_assoc(epb); 738 asoc = sctp_assoc(epb);
815 transport = sctp_assoc_is_matc 739 transport = sctp_assoc_is_match(asoc, local, peer);
816 if (transport) 740 if (transport)
817 goto hit; 741 goto hit;
818 } 742 }
819 743
820 read_unlock(&head->lock); 744 read_unlock(&head->lock);
821 745
822 return NULL; 746 return NULL;
823 747
824 hit: 748 hit:
825 *pt = transport; 749 *pt = transport;
826 sctp_association_hold(asoc); 750 sctp_association_hold(asoc);
>> 751 sock_hold(epb->sk);
827 read_unlock(&head->lock); 752 read_unlock(&head->lock);
828 return asoc; 753 return asoc;
829 } 754 }
830 755
831 /* Look up an association. BH-safe. */ 756 /* Look up an association. BH-safe. */
832 SCTP_STATIC 757 SCTP_STATIC
833 struct sctp_association *sctp_lookup_associati 758 struct sctp_association *sctp_lookup_association(const union sctp_addr *laddr,
834 759 const union sctp_addr *paddr,
835 st 760 struct sctp_transport **transportp)
836 { 761 {
837 struct sctp_association *asoc; 762 struct sctp_association *asoc;
838 763
839 sctp_local_bh_disable(); 764 sctp_local_bh_disable();
840 asoc = __sctp_lookup_association(laddr 765 asoc = __sctp_lookup_association(laddr, paddr, transportp);
841 sctp_local_bh_enable(); 766 sctp_local_bh_enable();
842 767
843 return asoc; 768 return asoc;
844 } 769 }
845 770
846 /* Is there an association matching the given 771 /* Is there an association matching the given local and peer addresses? */
847 int sctp_has_association(const union sctp_addr 772 int sctp_has_association(const union sctp_addr *laddr,
848 const union sctp_addr 773 const union sctp_addr *paddr)
849 { 774 {
850 struct sctp_association *asoc; 775 struct sctp_association *asoc;
851 struct sctp_transport *transport; 776 struct sctp_transport *transport;
852 777
853 if ((asoc = sctp_lookup_association(la 778 if ((asoc = sctp_lookup_association(laddr, paddr, &transport))) {
>> 779 sock_put(asoc->base.sk);
854 sctp_association_put(asoc); 780 sctp_association_put(asoc);
855 return 1; 781 return 1;
856 } 782 }
857 783
858 return 0; 784 return 0;
859 } 785 }
860 786
861 /* 787 /*
862 * SCTP Implementors Guide, 2.18 Handling of a 788 * SCTP Implementors Guide, 2.18 Handling of address
863 * parameters within the INIT or INIT-ACK. 789 * parameters within the INIT or INIT-ACK.
864 * 790 *
865 * D) When searching for a matching TCB upon r 791 * D) When searching for a matching TCB upon reception of an INIT
866 * or INIT-ACK chunk the receiver SHOULD us 792 * or INIT-ACK chunk the receiver SHOULD use not only the
867 * source address of the packet (containing 793 * source address of the packet (containing the INIT or
868 * INIT-ACK) but the receiver SHOULD also u 794 * INIT-ACK) but the receiver SHOULD also use all valid
869 * address parameters contained within the 795 * address parameters contained within the chunk.
870 * 796 *
871 * 2.18.3 Solution description 797 * 2.18.3 Solution description
872 * 798 *
873 * This new text clearly specifies to an imple 799 * This new text clearly specifies to an implementor the need
874 * to look within the INIT or INIT-ACK. Any im 800 * to look within the INIT or INIT-ACK. Any implementation that
875 * does not do this, may not be able to establ 801 * does not do this, may not be able to establish associations
876 * in certain circumstances. 802 * in certain circumstances.
877 * 803 *
878 */ 804 */
879 static struct sctp_association *__sctp_rcv_ini 805 static struct sctp_association *__sctp_rcv_init_lookup(struct sk_buff *skb,
880 const union sctp_addr *laddr, struct s 806 const union sctp_addr *laddr, struct sctp_transport **transportp)
881 { 807 {
882 struct sctp_association *asoc; 808 struct sctp_association *asoc;
883 union sctp_addr addr; 809 union sctp_addr addr;
884 union sctp_addr *paddr = &addr; 810 union sctp_addr *paddr = &addr;
885 struct sctphdr *sh = sctp_hdr(skb); !! 811 struct sctphdr *sh = (struct sctphdr *) skb->h.raw;
886 sctp_chunkhdr_t *ch; 812 sctp_chunkhdr_t *ch;
887 union sctp_params params; 813 union sctp_params params;
888 sctp_init_chunk_t *init; 814 sctp_init_chunk_t *init;
889 struct sctp_transport *transport; 815 struct sctp_transport *transport;
890 struct sctp_af *af; 816 struct sctp_af *af;
891 817
892 ch = (sctp_chunkhdr_t *) skb->data; 818 ch = (sctp_chunkhdr_t *) skb->data;
893 819
>> 820 /* If this is INIT/INIT-ACK look inside the chunk too. */
>> 821 switch (ch->type) {
>> 822 case SCTP_CID_INIT:
>> 823 case SCTP_CID_INIT_ACK:
>> 824 break;
>> 825 default:
>> 826 return NULL;
>> 827 }
>> 828
>> 829 /* The code below will attempt to walk the chunk and extract
>> 830 * parameter information. Before we do that, we need to verify
>> 831 * that the chunk length doesn't cause overflow. Otherwise, we'll
>> 832 * walk off the end.
>> 833 */
>> 834 if (WORD_ROUND(ntohs(ch->length)) > skb->len)
>> 835 return NULL;
>> 836
894 /* 837 /*
895 * This code will NOT touch anything i 838 * This code will NOT touch anything inside the chunk--it is
896 * strictly READ-ONLY. 839 * strictly READ-ONLY.
897 * 840 *
898 * RFC 2960 3 SCTP packet Format 841 * RFC 2960 3 SCTP packet Format
899 * 842 *
900 * Multiple chunks can be bundled into 843 * Multiple chunks can be bundled into one SCTP packet up to
901 * the MTU size, except for the INIT, 844 * the MTU size, except for the INIT, INIT ACK, and SHUTDOWN
902 * COMPLETE chunks. These chunks MUST 845 * COMPLETE chunks. These chunks MUST NOT be bundled with any
903 * other chunk in a packet. See Secti 846 * other chunk in a packet. See Section 6.10 for more details
904 * on chunk bundling. 847 * on chunk bundling.
905 */ 848 */
906 849
907 /* Find the start of the TLVs and the 850 /* Find the start of the TLVs and the end of the chunk. This is
908 * the region we search for address pa 851 * the region we search for address parameters.
909 */ 852 */
910 init = (sctp_init_chunk_t *)skb->data; 853 init = (sctp_init_chunk_t *)skb->data;
911 854
912 /* Walk the parameters looking for emb 855 /* Walk the parameters looking for embedded addresses. */
913 sctp_walk_params(params, init, init_hd 856 sctp_walk_params(params, init, init_hdr.params) {
914 857
915 /* Note: Ignoring hostname add 858 /* Note: Ignoring hostname addresses. */
916 af = sctp_get_af_specific(para 859 af = sctp_get_af_specific(param_type2af(params.p->type));
917 if (!af) 860 if (!af)
918 continue; 861 continue;
919 862
920 af->from_addr_param(paddr, par !! 863 af->from_addr_param(paddr, params.addr, ntohs(sh->source), 0);
921 864
922 asoc = __sctp_lookup_associati 865 asoc = __sctp_lookup_association(laddr, paddr, &transport);
923 if (asoc) 866 if (asoc)
924 return asoc; 867 return asoc;
925 } 868 }
926 869
927 return NULL; 870 return NULL;
928 } 871 }
929 872
930 /* ADD-IP, Section 5.2 <<
931 * When an endpoint receives an ASCONF Chunk f <<
932 * special procedures may be needed to identif <<
933 * ASCONF Chunk is associated with. To properl <<
934 * the following procedures SHOULD be followed <<
935 * <<
936 * D2) If the association is not found, use th <<
937 * Address Parameter TLV combined with the por <<
938 * SCTP common header. If found proceed to rul <<
939 * <<
940 * D2-ext) If more than one ASCONF Chunks are <<
941 * address found in the ASCONF Address Paramet <<
942 * subsequent ASCONF Chunks. If found, proceed <<
943 */ <<
944 static struct sctp_association *__sctp_rcv_asc <<
945 sctp_c <<
946 const <<
947 __be16 <<
948 struct <<
949 { <<
950 sctp_addip_chunk_t *asconf = (struct s <<
951 struct sctp_af *af; <<
952 union sctp_addr_param *param; <<
953 union sctp_addr paddr; <<
954 <<
955 /* Skip over the ADDIP header and find <<
956 param = (union sctp_addr_param *)(asco <<
957 <<
958 af = sctp_get_af_specific(param_type2a <<
959 if (unlikely(!af)) <<
960 return NULL; <<
961 <<
962 af->from_addr_param(&paddr, param, pee <<
963 <<
964 return __sctp_lookup_association(laddr <<
965 } <<
966 <<
967 <<
968 /* SCTP-AUTH, Section 6.3: <<
969 * If the receiver does not find a STCB for <<
970 * chunk as the first chunk and not a COOKIE <<
971 * chunk, it MUST use the chunks after the A <<
972 * association. <<
973 * <<
974 * This means that any chunks that can help us <<
975 * to be looked at to find this assocation. <<
976 */ <<
977 static struct sctp_association *__sctp_rcv_wal <<
978 const un <<
979 struct s <<
980 { <<
981 struct sctp_association *asoc = NULL; <<
982 sctp_chunkhdr_t *ch; <<
983 int have_auth = 0; <<
984 unsigned int chunk_num = 1; <<
985 __u8 *ch_end; <<
986 <<
987 /* Walk through the chunks looking for <<
988 * to help us find the association. <<
989 */ <<
990 ch = (sctp_chunkhdr_t *) skb->data; <<
991 do { <<
992 /* Break out if chunk length i <<
993 if (ntohs(ch->length) < sizeof <<
994 break; <<
995 <<
996 ch_end = ((__u8 *)ch) + WORD_R <<
997 if (ch_end > skb_tail_pointer( <<
998 break; <<
999 <<
1000 switch(ch->type) { <<
1001 case SCTP_CID_AUTH: <<
1002 have_auth = chunk <<
1003 break; <<
1004 <<
1005 case SCTP_CID_COOKIE_ECHO <<
1006 /* If a packet ar <<
1007 * a first chunk, <<
1008 * chunk, and pos <<
1009 * the receiver d <<
1010 * packet, then a <<
1011 * the contents o <<
1012 */ <<
1013 if (have_auth == <<
1014 return NU <<
1015 break; <<
1016 <<
1017 case SCTP_CID_ASCONF: <<
1018 if (have_auth || <<
1019 asoc = __ <<
1020 <<
1021 <<
1022 default: <<
1023 break; <<
1024 } <<
1025 <<
1026 if (asoc) <<
1027 break; <<
1028 <<
1029 ch = (sctp_chunkhdr_t *) ch_e <<
1030 chunk_num++; <<
1031 } while (ch_end < skb_tail_pointer(sk <<
1032 <<
1033 return asoc; <<
1034 } <<
1035 <<
1036 /* <<
1037 * There are circumstances when we need to lo <<
1038 * for information to help us find the associ <<
1039 * include looking inside of INIT/INIT-ACK ch <<
1040 * chunks. <<
1041 */ <<
1042 static struct sctp_association *__sctp_rcv_lo <<
1043 const u <<
1044 struct <<
1045 { <<
1046 sctp_chunkhdr_t *ch; <<
1047 <<
1048 ch = (sctp_chunkhdr_t *) skb->data; <<
1049 <<
1050 /* The code below will attempt to wal <<
1051 * parameter information. Before we <<
1052 * that the chunk length doesn't caus <<
1053 * walk off the end. <<
1054 */ <<
1055 if (WORD_ROUND(ntohs(ch->length)) > s <<
1056 return NULL; <<
1057 <<
1058 /* If this is INIT/INIT-ACK look insi <<
1059 switch (ch->type) { <<
1060 case SCTP_CID_INIT: <<
1061 case SCTP_CID_INIT_ACK: <<
1062 return __sctp_rcv_init_lookup <<
1063 break; <<
1064 <<
1065 default: <<
1066 return __sctp_rcv_walk_lookup <<
1067 break; <<
1068 } <<
1069 <<
1070 <<
1071 return NULL; <<
1072 } <<
1073 <<
1074 /* Lookup an association for an inbound skb. 873 /* Lookup an association for an inbound skb. */
1075 static struct sctp_association *__sctp_rcv_lo 874 static struct sctp_association *__sctp_rcv_lookup(struct sk_buff *skb,
1076 const u 875 const union sctp_addr *paddr,
1077 const u 876 const union sctp_addr *laddr,
1078 struct 877 struct sctp_transport **transportp)
1079 { 878 {
1080 struct sctp_association *asoc; 879 struct sctp_association *asoc;
1081 880
1082 asoc = __sctp_lookup_association(ladd 881 asoc = __sctp_lookup_association(laddr, paddr, transportp);
1083 882
1084 /* Further lookup for INIT/INIT-ACK p 883 /* Further lookup for INIT/INIT-ACK packets.
1085 * SCTP Implementors Guide, 2.18 Hand 884 * SCTP Implementors Guide, 2.18 Handling of address
1086 * parameters within the INIT or INIT 885 * parameters within the INIT or INIT-ACK.
1087 */ 886 */
1088 if (!asoc) 887 if (!asoc)
1089 asoc = __sctp_rcv_lookup_hard !! 888 asoc = __sctp_rcv_init_lookup(skb, laddr, transportp);
1090 889
1091 return asoc; 890 return asoc;
1092 } 891 }
1093 892
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