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Commit | Line | Data |
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9fb9cbb1 YK |
1 | /* |
2 | * Connection tracking protocol helper module for SCTP. | |
601e68e1 YH |
3 | * |
4 | * SCTP is defined in RFC 2960. References to various sections in this code | |
9fb9cbb1 | 5 | * are to this RFC. |
601e68e1 | 6 | * |
9fb9cbb1 YK |
7 | * This program is free software; you can redistribute it and/or modify |
8 | * it under the terms of the GNU General Public License version 2 as | |
9 | * published by the Free Software Foundation. | |
9fb9cbb1 YK |
10 | */ |
11 | ||
12 | #include <linux/types.h> | |
9fb9cbb1 YK |
13 | #include <linux/timer.h> |
14 | #include <linux/netfilter.h> | |
15 | #include <linux/module.h> | |
16 | #include <linux/in.h> | |
17 | #include <linux/ip.h> | |
18 | #include <linux/sctp.h> | |
19 | #include <linux/string.h> | |
20 | #include <linux/seq_file.h> | |
40a839fd YK |
21 | #include <linux/spinlock.h> |
22 | #include <linux/interrupt.h> | |
9fb9cbb1 YK |
23 | |
24 | #include <net/netfilter/nf_conntrack.h> | |
605dcad6 | 25 | #include <net/netfilter/nf_conntrack_l4proto.h> |
f6180121 | 26 | #include <net/netfilter/nf_conntrack_ecache.h> |
9fb9cbb1 | 27 | |
9fb9cbb1 | 28 | /* FIXME: Examine ipfilter's timeouts and conntrack transitions more |
601e68e1 | 29 | closely. They're more complex. --RR |
9fb9cbb1 YK |
30 | |
31 | And so for me for SCTP :D -Kiran */ | |
32 | ||
12c33aa2 | 33 | static const char *const sctp_conntrack_names[] = { |
9fb9cbb1 YK |
34 | "NONE", |
35 | "CLOSED", | |
36 | "COOKIE_WAIT", | |
37 | "COOKIE_ECHOED", | |
38 | "ESTABLISHED", | |
39 | "SHUTDOWN_SENT", | |
40 | "SHUTDOWN_RECD", | |
41 | "SHUTDOWN_ACK_SENT", | |
42 | }; | |
43 | ||
44 | #define SECS * HZ | |
45 | #define MINS * 60 SECS | |
46 | #define HOURS * 60 MINS | |
47 | #define DAYS * 24 HOURS | |
48 | ||
86c0bf40 PM |
49 | static unsigned int sctp_timeouts[SCTP_CONNTRACK_MAX] __read_mostly = { |
50 | [SCTP_CONNTRACK_CLOSED] = 10 SECS, | |
51 | [SCTP_CONNTRACK_COOKIE_WAIT] = 3 SECS, | |
52 | [SCTP_CONNTRACK_COOKIE_ECHOED] = 3 SECS, | |
53 | [SCTP_CONNTRACK_ESTABLISHED] = 5 DAYS, | |
54 | [SCTP_CONNTRACK_SHUTDOWN_SENT] = 300 SECS / 1000, | |
55 | [SCTP_CONNTRACK_SHUTDOWN_RECD] = 300 SECS / 1000, | |
56 | [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT] = 3 SECS, | |
57 | }; | |
9fb9cbb1 YK |
58 | |
59 | #define sNO SCTP_CONNTRACK_NONE | |
60 | #define sCL SCTP_CONNTRACK_CLOSED | |
61 | #define sCW SCTP_CONNTRACK_COOKIE_WAIT | |
62 | #define sCE SCTP_CONNTRACK_COOKIE_ECHOED | |
63 | #define sES SCTP_CONNTRACK_ESTABLISHED | |
64 | #define sSS SCTP_CONNTRACK_SHUTDOWN_SENT | |
65 | #define sSR SCTP_CONNTRACK_SHUTDOWN_RECD | |
66 | #define sSA SCTP_CONNTRACK_SHUTDOWN_ACK_SENT | |
67 | #define sIV SCTP_CONNTRACK_MAX | |
68 | ||
601e68e1 | 69 | /* |
9fb9cbb1 YK |
70 | These are the descriptions of the states: |
71 | ||
601e68e1 | 72 | NOTE: These state names are tantalizingly similar to the states of an |
9fb9cbb1 | 73 | SCTP endpoint. But the interpretation of the states is a little different, |
601e68e1 | 74 | considering that these are the states of the connection and not of an end |
9fb9cbb1 YK |
75 | point. Please note the subtleties. -Kiran |
76 | ||
77 | NONE - Nothing so far. | |
601e68e1 YH |
78 | COOKIE WAIT - We have seen an INIT chunk in the original direction, or also |
79 | an INIT_ACK chunk in the reply direction. | |
9fb9cbb1 YK |
80 | COOKIE ECHOED - We have seen a COOKIE_ECHO chunk in the original direction. |
81 | ESTABLISHED - We have seen a COOKIE_ACK in the reply direction. | |
82 | SHUTDOWN_SENT - We have seen a SHUTDOWN chunk in the original direction. | |
83 | SHUTDOWN_RECD - We have seen a SHUTDOWN chunk in the reply directoin. | |
84 | SHUTDOWN_ACK_SENT - We have seen a SHUTDOWN_ACK chunk in the direction opposite | |
601e68e1 YH |
85 | to that of the SHUTDOWN chunk. |
86 | CLOSED - We have seen a SHUTDOWN_COMPLETE chunk in the direction of | |
87 | the SHUTDOWN chunk. Connection is closed. | |
9fb9cbb1 YK |
88 | */ |
89 | ||
90 | /* TODO | |
601e68e1 | 91 | - I have assumed that the first INIT is in the original direction. |
9fb9cbb1 YK |
92 | This messes things when an INIT comes in the reply direction in CLOSED |
93 | state. | |
601e68e1 | 94 | - Check the error type in the reply dir before transitioning from |
9fb9cbb1 YK |
95 | cookie echoed to closed. |
96 | - Sec 5.2.4 of RFC 2960 | |
97 | - Multi Homing support. | |
98 | */ | |
99 | ||
100 | /* SCTP conntrack state transitions */ | |
a5e73c29 | 101 | static const u8 sctp_conntracks[2][9][SCTP_CONNTRACK_MAX] = { |
9fb9cbb1 YK |
102 | { |
103 | /* ORIGINAL */ | |
104 | /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA */ | |
105 | /* init */ {sCW, sCW, sCW, sCE, sES, sSS, sSR, sSA}, | |
106 | /* init_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA}, | |
107 | /* abort */ {sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL}, | |
108 | /* shutdown */ {sCL, sCL, sCW, sCE, sSS, sSS, sSR, sSA}, | |
109 | /* shutdown_ack */ {sSA, sCL, sCW, sCE, sES, sSA, sSA, sSA}, | |
25985edc | 110 | /* error */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* Can't have Stale cookie*/ |
9fb9cbb1 | 111 | /* cookie_echo */ {sCL, sCL, sCE, sCE, sES, sSS, sSR, sSA},/* 5.2.4 - Big TODO */ |
25985edc | 112 | /* cookie_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* Can't come in orig dir */ |
9fb9cbb1 YK |
113 | /* shutdown_comp*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sCL} |
114 | }, | |
115 | { | |
116 | /* REPLY */ | |
117 | /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA */ | |
118 | /* init */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* INIT in sCL Big TODO */ | |
119 | /* init_ack */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA}, | |
120 | /* abort */ {sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL}, | |
121 | /* shutdown */ {sIV, sCL, sCW, sCE, sSR, sSS, sSR, sSA}, | |
122 | /* shutdown_ack */ {sIV, sCL, sCW, sCE, sES, sSA, sSA, sSA}, | |
123 | /* error */ {sIV, sCL, sCW, sCL, sES, sSS, sSR, sSA}, | |
25985edc | 124 | /* cookie_echo */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA},/* Can't come in reply dir */ |
9fb9cbb1 YK |
125 | /* cookie_ack */ {sIV, sCL, sCW, sES, sES, sSS, sSR, sSA}, |
126 | /* shutdown_comp*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sCL} | |
127 | } | |
128 | }; | |
129 | ||
09f263cd JE |
130 | static bool sctp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff, |
131 | struct nf_conntrack_tuple *tuple) | |
9fb9cbb1 | 132 | { |
12c33aa2 JE |
133 | const struct sctphdr *hp; |
134 | struct sctphdr _hdr; | |
9fb9cbb1 | 135 | |
9fb9cbb1 YK |
136 | /* Actually only need first 8 bytes. */ |
137 | hp = skb_header_pointer(skb, dataoff, 8, &_hdr); | |
138 | if (hp == NULL) | |
09f263cd | 139 | return false; |
9fb9cbb1 YK |
140 | |
141 | tuple->src.u.sctp.port = hp->source; | |
142 | tuple->dst.u.sctp.port = hp->dest; | |
09f263cd | 143 | return true; |
9fb9cbb1 YK |
144 | } |
145 | ||
09f263cd JE |
146 | static bool sctp_invert_tuple(struct nf_conntrack_tuple *tuple, |
147 | const struct nf_conntrack_tuple *orig) | |
9fb9cbb1 | 148 | { |
9fb9cbb1 YK |
149 | tuple->src.u.sctp.port = orig->dst.u.sctp.port; |
150 | tuple->dst.u.sctp.port = orig->src.u.sctp.port; | |
09f263cd | 151 | return true; |
9fb9cbb1 YK |
152 | } |
153 | ||
154 | /* Print out the per-protocol part of the tuple. */ | |
155 | static int sctp_print_tuple(struct seq_file *s, | |
156 | const struct nf_conntrack_tuple *tuple) | |
157 | { | |
9fb9cbb1 YK |
158 | return seq_printf(s, "sport=%hu dport=%hu ", |
159 | ntohs(tuple->src.u.sctp.port), | |
160 | ntohs(tuple->dst.u.sctp.port)); | |
161 | } | |
162 | ||
163 | /* Print out the private part of the conntrack. */ | |
440f0d58 | 164 | static int sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct) |
9fb9cbb1 YK |
165 | { |
166 | enum sctp_conntrack state; | |
167 | ||
440f0d58 | 168 | spin_lock_bh(&ct->lock); |
112f35c9 | 169 | state = ct->proto.sctp.state; |
440f0d58 | 170 | spin_unlock_bh(&ct->lock); |
9fb9cbb1 YK |
171 | |
172 | return seq_printf(s, "%s ", sctp_conntrack_names[state]); | |
173 | } | |
174 | ||
175 | #define for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) \ | |
e79ec50b JE |
176 | for ((offset) = (dataoff) + sizeof(sctp_sctphdr_t), (count) = 0; \ |
177 | (offset) < (skb)->len && \ | |
178 | ((sch) = skb_header_pointer((skb), (offset), sizeof(_sch), &(_sch))); \ | |
179 | (offset) += (ntohs((sch)->length) + 3) & ~3, (count)++) | |
9fb9cbb1 YK |
180 | |
181 | /* Some validity checks to make sure the chunks are fine */ | |
112f35c9 | 182 | static int do_basic_checks(struct nf_conn *ct, |
9fb9cbb1 YK |
183 | const struct sk_buff *skb, |
184 | unsigned int dataoff, | |
35c6d3cb | 185 | unsigned long *map) |
9fb9cbb1 YK |
186 | { |
187 | u_int32_t offset, count; | |
188 | sctp_chunkhdr_t _sch, *sch; | |
189 | int flag; | |
190 | ||
9fb9cbb1 YK |
191 | flag = 0; |
192 | ||
193 | for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { | |
0d53778e | 194 | pr_debug("Chunk Num: %d Type: %d\n", count, sch->type); |
9fb9cbb1 | 195 | |
5447d477 PM |
196 | if (sch->type == SCTP_CID_INIT || |
197 | sch->type == SCTP_CID_INIT_ACK || | |
198 | sch->type == SCTP_CID_SHUTDOWN_COMPLETE) | |
9fb9cbb1 | 199 | flag = 1; |
9fb9cbb1 | 200 | |
e17df688 PM |
201 | /* |
202 | * Cookie Ack/Echo chunks not the first OR | |
203 | * Init / Init Ack / Shutdown compl chunks not the only chunks | |
204 | * OR zero-length. | |
205 | */ | |
5447d477 PM |
206 | if (((sch->type == SCTP_CID_COOKIE_ACK || |
207 | sch->type == SCTP_CID_COOKIE_ECHO || | |
208 | flag) && | |
209 | count != 0) || !sch->length) { | |
0d53778e | 210 | pr_debug("Basic checks failed\n"); |
9fb9cbb1 YK |
211 | return 1; |
212 | } | |
213 | ||
5447d477 | 214 | if (map) |
35c6d3cb | 215 | set_bit(sch->type, map); |
9fb9cbb1 YK |
216 | } |
217 | ||
0d53778e | 218 | pr_debug("Basic checks passed\n"); |
dd7271fe | 219 | return count == 0; |
9fb9cbb1 YK |
220 | } |
221 | ||
efe9f68a PM |
222 | static int sctp_new_state(enum ip_conntrack_dir dir, |
223 | enum sctp_conntrack cur_state, | |
224 | int chunk_type) | |
9fb9cbb1 YK |
225 | { |
226 | int i; | |
227 | ||
0d53778e | 228 | pr_debug("Chunk type: %d\n", chunk_type); |
9fb9cbb1 YK |
229 | |
230 | switch (chunk_type) { | |
5447d477 PM |
231 | case SCTP_CID_INIT: |
232 | pr_debug("SCTP_CID_INIT\n"); | |
233 | i = 0; | |
234 | break; | |
235 | case SCTP_CID_INIT_ACK: | |
236 | pr_debug("SCTP_CID_INIT_ACK\n"); | |
237 | i = 1; | |
238 | break; | |
239 | case SCTP_CID_ABORT: | |
240 | pr_debug("SCTP_CID_ABORT\n"); | |
241 | i = 2; | |
242 | break; | |
243 | case SCTP_CID_SHUTDOWN: | |
244 | pr_debug("SCTP_CID_SHUTDOWN\n"); | |
245 | i = 3; | |
246 | break; | |
247 | case SCTP_CID_SHUTDOWN_ACK: | |
248 | pr_debug("SCTP_CID_SHUTDOWN_ACK\n"); | |
249 | i = 4; | |
250 | break; | |
251 | case SCTP_CID_ERROR: | |
252 | pr_debug("SCTP_CID_ERROR\n"); | |
253 | i = 5; | |
254 | break; | |
255 | case SCTP_CID_COOKIE_ECHO: | |
256 | pr_debug("SCTP_CID_COOKIE_ECHO\n"); | |
257 | i = 6; | |
258 | break; | |
259 | case SCTP_CID_COOKIE_ACK: | |
260 | pr_debug("SCTP_CID_COOKIE_ACK\n"); | |
261 | i = 7; | |
262 | break; | |
263 | case SCTP_CID_SHUTDOWN_COMPLETE: | |
264 | pr_debug("SCTP_CID_SHUTDOWN_COMPLETE\n"); | |
265 | i = 8; | |
266 | break; | |
267 | default: | |
268 | /* Other chunks like DATA, SACK, HEARTBEAT and | |
269 | its ACK do not cause a change in state */ | |
270 | pr_debug("Unknown chunk type, Will stay in %s\n", | |
271 | sctp_conntrack_names[cur_state]); | |
272 | return cur_state; | |
9fb9cbb1 YK |
273 | } |
274 | ||
0d53778e PM |
275 | pr_debug("dir: %d cur_state: %s chunk_type: %d new_state: %s\n", |
276 | dir, sctp_conntrack_names[cur_state], chunk_type, | |
277 | sctp_conntrack_names[sctp_conntracks[dir][i][cur_state]]); | |
9fb9cbb1 YK |
278 | |
279 | return sctp_conntracks[dir][i][cur_state]; | |
280 | } | |
281 | ||
2c8503f5 PNA |
282 | static unsigned int *sctp_get_timeouts(struct net *net) |
283 | { | |
284 | return sctp_timeouts; | |
285 | } | |
286 | ||
b37e933a | 287 | /* Returns verdict for packet, or -NF_ACCEPT for invalid. */ |
112f35c9 | 288 | static int sctp_packet(struct nf_conn *ct, |
9fb9cbb1 YK |
289 | const struct sk_buff *skb, |
290 | unsigned int dataoff, | |
291 | enum ip_conntrack_info ctinfo, | |
76108cea | 292 | u_int8_t pf, |
2c8503f5 PNA |
293 | unsigned int hooknum, |
294 | unsigned int *timeouts) | |
9fb9cbb1 | 295 | { |
efe9f68a | 296 | enum sctp_conntrack new_state, old_state; |
8528819a | 297 | enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); |
12c33aa2 JE |
298 | const struct sctphdr *sh; |
299 | struct sctphdr _sctph; | |
300 | const struct sctp_chunkhdr *sch; | |
301 | struct sctp_chunkhdr _sch; | |
9fb9cbb1 | 302 | u_int32_t offset, count; |
35c6d3cb | 303 | unsigned long map[256 / sizeof(unsigned long)] = { 0 }; |
9fb9cbb1 | 304 | |
9fb9cbb1 YK |
305 | sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph); |
306 | if (sh == NULL) | |
b37e933a | 307 | goto out; |
9fb9cbb1 | 308 | |
112f35c9 | 309 | if (do_basic_checks(ct, skb, dataoff, map) != 0) |
b37e933a | 310 | goto out; |
9fb9cbb1 YK |
311 | |
312 | /* Check the verification tag (Sec 8.5) */ | |
35c6d3cb PM |
313 | if (!test_bit(SCTP_CID_INIT, map) && |
314 | !test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) && | |
315 | !test_bit(SCTP_CID_COOKIE_ECHO, map) && | |
316 | !test_bit(SCTP_CID_ABORT, map) && | |
317 | !test_bit(SCTP_CID_SHUTDOWN_ACK, map) && | |
8528819a | 318 | sh->vtag != ct->proto.sctp.vtag[dir]) { |
0d53778e | 319 | pr_debug("Verification tag check failed\n"); |
b37e933a | 320 | goto out; |
9fb9cbb1 YK |
321 | } |
322 | ||
328bd899 | 323 | old_state = new_state = SCTP_CONNTRACK_NONE; |
440f0d58 | 324 | spin_lock_bh(&ct->lock); |
9fb9cbb1 | 325 | for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { |
9fb9cbb1 YK |
326 | /* Special cases of Verification tag check (Sec 8.5.1) */ |
327 | if (sch->type == SCTP_CID_INIT) { | |
328 | /* Sec 8.5.1 (A) */ | |
b37e933a PM |
329 | if (sh->vtag != 0) |
330 | goto out_unlock; | |
9fb9cbb1 YK |
331 | } else if (sch->type == SCTP_CID_ABORT) { |
332 | /* Sec 8.5.1 (B) */ | |
8528819a | 333 | if (sh->vtag != ct->proto.sctp.vtag[dir] && |
b37e933a PM |
334 | sh->vtag != ct->proto.sctp.vtag[!dir]) |
335 | goto out_unlock; | |
9fb9cbb1 YK |
336 | } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) { |
337 | /* Sec 8.5.1 (C) */ | |
8528819a PM |
338 | if (sh->vtag != ct->proto.sctp.vtag[dir] && |
339 | sh->vtag != ct->proto.sctp.vtag[!dir] && | |
9b1c2cfd | 340 | sch->flags & SCTP_CHUNK_FLAG_T) |
b37e933a | 341 | goto out_unlock; |
9fb9cbb1 YK |
342 | } else if (sch->type == SCTP_CID_COOKIE_ECHO) { |
343 | /* Sec 8.5.1 (D) */ | |
b37e933a PM |
344 | if (sh->vtag != ct->proto.sctp.vtag[dir]) |
345 | goto out_unlock; | |
9fb9cbb1 YK |
346 | } |
347 | ||
efe9f68a PM |
348 | old_state = ct->proto.sctp.state; |
349 | new_state = sctp_new_state(dir, old_state, sch->type); | |
9fb9cbb1 YK |
350 | |
351 | /* Invalid */ | |
efe9f68a | 352 | if (new_state == SCTP_CONNTRACK_MAX) { |
0d53778e PM |
353 | pr_debug("nf_conntrack_sctp: Invalid dir=%i ctype=%u " |
354 | "conntrack=%u\n", | |
efe9f68a | 355 | dir, sch->type, old_state); |
b37e933a | 356 | goto out_unlock; |
9fb9cbb1 YK |
357 | } |
358 | ||
359 | /* If it is an INIT or an INIT ACK note down the vtag */ | |
5447d477 PM |
360 | if (sch->type == SCTP_CID_INIT || |
361 | sch->type == SCTP_CID_INIT_ACK) { | |
9fb9cbb1 YK |
362 | sctp_inithdr_t _inithdr, *ih; |
363 | ||
364 | ih = skb_header_pointer(skb, offset + sizeof(sctp_chunkhdr_t), | |
601e68e1 | 365 | sizeof(_inithdr), &_inithdr); |
b37e933a PM |
366 | if (ih == NULL) |
367 | goto out_unlock; | |
0d53778e | 368 | pr_debug("Setting vtag %x for dir %d\n", |
8528819a PM |
369 | ih->init_tag, !dir); |
370 | ct->proto.sctp.vtag[!dir] = ih->init_tag; | |
9fb9cbb1 YK |
371 | } |
372 | ||
efe9f68a PM |
373 | ct->proto.sctp.state = new_state; |
374 | if (old_state != new_state) | |
a71996fc | 375 | nf_conntrack_event_cache(IPCT_PROTOINFO, ct); |
9fb9cbb1 | 376 | } |
440f0d58 | 377 | spin_unlock_bh(&ct->lock); |
9fb9cbb1 | 378 | |
2c8503f5 | 379 | nf_ct_refresh_acct(ct, ctinfo, skb, timeouts[new_state]); |
9fb9cbb1 | 380 | |
efe9f68a | 381 | if (old_state == SCTP_CONNTRACK_COOKIE_ECHOED && |
8528819a | 382 | dir == IP_CT_DIR_REPLY && |
efe9f68a | 383 | new_state == SCTP_CONNTRACK_ESTABLISHED) { |
0d53778e | 384 | pr_debug("Setting assured bit\n"); |
112f35c9 | 385 | set_bit(IPS_ASSURED_BIT, &ct->status); |
858b3133 | 386 | nf_conntrack_event_cache(IPCT_ASSURED, ct); |
9fb9cbb1 YK |
387 | } |
388 | ||
389 | return NF_ACCEPT; | |
b37e933a PM |
390 | |
391 | out_unlock: | |
440f0d58 | 392 | spin_unlock_bh(&ct->lock); |
b37e933a PM |
393 | out: |
394 | return -NF_ACCEPT; | |
9fb9cbb1 YK |
395 | } |
396 | ||
397 | /* Called when a new connection for this protocol found. */ | |
09f263cd | 398 | static bool sctp_new(struct nf_conn *ct, const struct sk_buff *skb, |
2c8503f5 | 399 | unsigned int dataoff, unsigned int *timeouts) |
9fb9cbb1 | 400 | { |
efe9f68a | 401 | enum sctp_conntrack new_state; |
12c33aa2 JE |
402 | const struct sctphdr *sh; |
403 | struct sctphdr _sctph; | |
404 | const struct sctp_chunkhdr *sch; | |
405 | struct sctp_chunkhdr _sch; | |
9fb9cbb1 | 406 | u_int32_t offset, count; |
35c6d3cb | 407 | unsigned long map[256 / sizeof(unsigned long)] = { 0 }; |
9fb9cbb1 | 408 | |
9fb9cbb1 YK |
409 | sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph); |
410 | if (sh == NULL) | |
09f263cd | 411 | return false; |
9fb9cbb1 | 412 | |
112f35c9 | 413 | if (do_basic_checks(ct, skb, dataoff, map) != 0) |
09f263cd | 414 | return false; |
9fb9cbb1 YK |
415 | |
416 | /* If an OOTB packet has any of these chunks discard (Sec 8.4) */ | |
35c6d3cb PM |
417 | if (test_bit(SCTP_CID_ABORT, map) || |
418 | test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) || | |
419 | test_bit(SCTP_CID_COOKIE_ACK, map)) | |
09f263cd | 420 | return false; |
9fb9cbb1 | 421 | |
e5fc9e7a | 422 | memset(&ct->proto.sctp, 0, sizeof(ct->proto.sctp)); |
efe9f68a | 423 | new_state = SCTP_CONNTRACK_MAX; |
9fb9cbb1 YK |
424 | for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { |
425 | /* Don't need lock here: this conntrack not in circulation yet */ | |
efe9f68a PM |
426 | new_state = sctp_new_state(IP_CT_DIR_ORIGINAL, |
427 | SCTP_CONNTRACK_NONE, sch->type); | |
9fb9cbb1 YK |
428 | |
429 | /* Invalid: delete conntrack */ | |
efe9f68a PM |
430 | if (new_state == SCTP_CONNTRACK_NONE || |
431 | new_state == SCTP_CONNTRACK_MAX) { | |
0d53778e | 432 | pr_debug("nf_conntrack_sctp: invalid new deleting.\n"); |
09f263cd | 433 | return false; |
9fb9cbb1 YK |
434 | } |
435 | ||
436 | /* Copy the vtag into the state info */ | |
437 | if (sch->type == SCTP_CID_INIT) { | |
438 | if (sh->vtag == 0) { | |
439 | sctp_inithdr_t _inithdr, *ih; | |
440 | ||
441 | ih = skb_header_pointer(skb, offset + sizeof(sctp_chunkhdr_t), | |
601e68e1 | 442 | sizeof(_inithdr), &_inithdr); |
9fb9cbb1 | 443 | if (ih == NULL) |
09f263cd | 444 | return false; |
9fb9cbb1 | 445 | |
0d53778e PM |
446 | pr_debug("Setting vtag %x for new conn\n", |
447 | ih->init_tag); | |
9fb9cbb1 | 448 | |
112f35c9 | 449 | ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = |
9fb9cbb1 YK |
450 | ih->init_tag; |
451 | } else { | |
452 | /* Sec 8.5.1 (A) */ | |
09f263cd | 453 | return false; |
9fb9cbb1 YK |
454 | } |
455 | } | |
456 | /* If it is a shutdown ack OOTB packet, we expect a return | |
457 | shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8) */ | |
458 | else { | |
0d53778e PM |
459 | pr_debug("Setting vtag %x for new conn OOTB\n", |
460 | sh->vtag); | |
112f35c9 | 461 | ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = sh->vtag; |
9fb9cbb1 YK |
462 | } |
463 | ||
efe9f68a | 464 | ct->proto.sctp.state = new_state; |
9fb9cbb1 YK |
465 | } |
466 | ||
09f263cd | 467 | return true; |
9fb9cbb1 YK |
468 | } |
469 | ||
c0cd1156 | 470 | #if IS_ENABLED(CONFIG_NF_CT_NETLINK) |
a258860e PNA |
471 | |
472 | #include <linux/netfilter/nfnetlink.h> | |
473 | #include <linux/netfilter/nfnetlink_conntrack.h> | |
474 | ||
475 | static int sctp_to_nlattr(struct sk_buff *skb, struct nlattr *nla, | |
440f0d58 | 476 | struct nf_conn *ct) |
a258860e PNA |
477 | { |
478 | struct nlattr *nest_parms; | |
479 | ||
440f0d58 | 480 | spin_lock_bh(&ct->lock); |
a258860e PNA |
481 | nest_parms = nla_nest_start(skb, CTA_PROTOINFO_SCTP | NLA_F_NESTED); |
482 | if (!nest_parms) | |
483 | goto nla_put_failure; | |
484 | ||
485 | NLA_PUT_U8(skb, CTA_PROTOINFO_SCTP_STATE, ct->proto.sctp.state); | |
486 | ||
487 | NLA_PUT_BE32(skb, | |
488 | CTA_PROTOINFO_SCTP_VTAG_ORIGINAL, | |
5547cd0a | 489 | ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL]); |
a258860e PNA |
490 | |
491 | NLA_PUT_BE32(skb, | |
492 | CTA_PROTOINFO_SCTP_VTAG_REPLY, | |
5547cd0a | 493 | ct->proto.sctp.vtag[IP_CT_DIR_REPLY]); |
a258860e | 494 | |
440f0d58 | 495 | spin_unlock_bh(&ct->lock); |
a258860e PNA |
496 | |
497 | nla_nest_end(skb, nest_parms); | |
498 | ||
499 | return 0; | |
500 | ||
501 | nla_put_failure: | |
440f0d58 | 502 | spin_unlock_bh(&ct->lock); |
a258860e PNA |
503 | return -1; |
504 | } | |
505 | ||
506 | static const struct nla_policy sctp_nla_policy[CTA_PROTOINFO_SCTP_MAX+1] = { | |
507 | [CTA_PROTOINFO_SCTP_STATE] = { .type = NLA_U8 }, | |
508 | [CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] = { .type = NLA_U32 }, | |
509 | [CTA_PROTOINFO_SCTP_VTAG_REPLY] = { .type = NLA_U32 }, | |
510 | }; | |
511 | ||
512 | static int nlattr_to_sctp(struct nlattr *cda[], struct nf_conn *ct) | |
513 | { | |
514 | struct nlattr *attr = cda[CTA_PROTOINFO_SCTP]; | |
515 | struct nlattr *tb[CTA_PROTOINFO_SCTP_MAX+1]; | |
516 | int err; | |
517 | ||
518 | /* updates may not contain the internal protocol info, skip parsing */ | |
519 | if (!attr) | |
520 | return 0; | |
521 | ||
522 | err = nla_parse_nested(tb, | |
523 | CTA_PROTOINFO_SCTP_MAX, | |
524 | attr, | |
525 | sctp_nla_policy); | |
526 | if (err < 0) | |
527 | return err; | |
528 | ||
529 | if (!tb[CTA_PROTOINFO_SCTP_STATE] || | |
530 | !tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] || | |
531 | !tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]) | |
532 | return -EINVAL; | |
533 | ||
440f0d58 | 534 | spin_lock_bh(&ct->lock); |
a258860e PNA |
535 | ct->proto.sctp.state = nla_get_u8(tb[CTA_PROTOINFO_SCTP_STATE]); |
536 | ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = | |
5547cd0a | 537 | nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL]); |
a258860e | 538 | ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = |
5547cd0a | 539 | nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]); |
440f0d58 | 540 | spin_unlock_bh(&ct->lock); |
a258860e PNA |
541 | |
542 | return 0; | |
543 | } | |
a400c30e HE |
544 | |
545 | static int sctp_nlattr_size(void) | |
546 | { | |
547 | return nla_total_size(0) /* CTA_PROTOINFO_SCTP */ | |
548 | + nla_policy_len(sctp_nla_policy, CTA_PROTOINFO_SCTP_MAX + 1); | |
549 | } | |
a258860e PNA |
550 | #endif |
551 | ||
9fb9cbb1 | 552 | #ifdef CONFIG_SYSCTL |
933a41e7 PM |
553 | static unsigned int sctp_sysctl_table_users; |
554 | static struct ctl_table_header *sctp_sysctl_header; | |
555 | static struct ctl_table sctp_sysctl_table[] = { | |
9fb9cbb1 | 556 | { |
9fb9cbb1 | 557 | .procname = "nf_conntrack_sctp_timeout_closed", |
86c0bf40 | 558 | .data = &sctp_timeouts[SCTP_CONNTRACK_CLOSED], |
9fb9cbb1 YK |
559 | .maxlen = sizeof(unsigned int), |
560 | .mode = 0644, | |
6d9f239a | 561 | .proc_handler = proc_dointvec_jiffies, |
9fb9cbb1 YK |
562 | }, |
563 | { | |
9fb9cbb1 | 564 | .procname = "nf_conntrack_sctp_timeout_cookie_wait", |
86c0bf40 | 565 | .data = &sctp_timeouts[SCTP_CONNTRACK_COOKIE_WAIT], |
9fb9cbb1 YK |
566 | .maxlen = sizeof(unsigned int), |
567 | .mode = 0644, | |
6d9f239a | 568 | .proc_handler = proc_dointvec_jiffies, |
9fb9cbb1 YK |
569 | }, |
570 | { | |
9fb9cbb1 | 571 | .procname = "nf_conntrack_sctp_timeout_cookie_echoed", |
86c0bf40 | 572 | .data = &sctp_timeouts[SCTP_CONNTRACK_COOKIE_ECHOED], |
9fb9cbb1 YK |
573 | .maxlen = sizeof(unsigned int), |
574 | .mode = 0644, | |
6d9f239a | 575 | .proc_handler = proc_dointvec_jiffies, |
9fb9cbb1 YK |
576 | }, |
577 | { | |
9fb9cbb1 | 578 | .procname = "nf_conntrack_sctp_timeout_established", |
86c0bf40 | 579 | .data = &sctp_timeouts[SCTP_CONNTRACK_ESTABLISHED], |
9fb9cbb1 YK |
580 | .maxlen = sizeof(unsigned int), |
581 | .mode = 0644, | |
6d9f239a | 582 | .proc_handler = proc_dointvec_jiffies, |
9fb9cbb1 YK |
583 | }, |
584 | { | |
9fb9cbb1 | 585 | .procname = "nf_conntrack_sctp_timeout_shutdown_sent", |
86c0bf40 | 586 | .data = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT], |
9fb9cbb1 YK |
587 | .maxlen = sizeof(unsigned int), |
588 | .mode = 0644, | |
6d9f239a | 589 | .proc_handler = proc_dointvec_jiffies, |
9fb9cbb1 YK |
590 | }, |
591 | { | |
9fb9cbb1 | 592 | .procname = "nf_conntrack_sctp_timeout_shutdown_recd", |
86c0bf40 | 593 | .data = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD], |
9fb9cbb1 YK |
594 | .maxlen = sizeof(unsigned int), |
595 | .mode = 0644, | |
6d9f239a | 596 | .proc_handler = proc_dointvec_jiffies, |
9fb9cbb1 YK |
597 | }, |
598 | { | |
9fb9cbb1 | 599 | .procname = "nf_conntrack_sctp_timeout_shutdown_ack_sent", |
86c0bf40 | 600 | .data = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT], |
9fb9cbb1 YK |
601 | .maxlen = sizeof(unsigned int), |
602 | .mode = 0644, | |
6d9f239a | 603 | .proc_handler = proc_dointvec_jiffies, |
9fb9cbb1 | 604 | }, |
f8572d8f | 605 | { } |
9fb9cbb1 | 606 | }; |
a999e683 PM |
607 | |
608 | #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT | |
609 | static struct ctl_table sctp_compat_sysctl_table[] = { | |
610 | { | |
a999e683 | 611 | .procname = "ip_conntrack_sctp_timeout_closed", |
86c0bf40 | 612 | .data = &sctp_timeouts[SCTP_CONNTRACK_CLOSED], |
a999e683 PM |
613 | .maxlen = sizeof(unsigned int), |
614 | .mode = 0644, | |
6d9f239a | 615 | .proc_handler = proc_dointvec_jiffies, |
a999e683 PM |
616 | }, |
617 | { | |
a999e683 | 618 | .procname = "ip_conntrack_sctp_timeout_cookie_wait", |
86c0bf40 | 619 | .data = &sctp_timeouts[SCTP_CONNTRACK_COOKIE_WAIT], |
a999e683 PM |
620 | .maxlen = sizeof(unsigned int), |
621 | .mode = 0644, | |
6d9f239a | 622 | .proc_handler = proc_dointvec_jiffies, |
a999e683 PM |
623 | }, |
624 | { | |
a999e683 | 625 | .procname = "ip_conntrack_sctp_timeout_cookie_echoed", |
86c0bf40 | 626 | .data = &sctp_timeouts[SCTP_CONNTRACK_COOKIE_ECHOED], |
a999e683 PM |
627 | .maxlen = sizeof(unsigned int), |
628 | .mode = 0644, | |
6d9f239a | 629 | .proc_handler = proc_dointvec_jiffies, |
a999e683 PM |
630 | }, |
631 | { | |
a999e683 | 632 | .procname = "ip_conntrack_sctp_timeout_established", |
86c0bf40 | 633 | .data = &sctp_timeouts[SCTP_CONNTRACK_ESTABLISHED], |
a999e683 PM |
634 | .maxlen = sizeof(unsigned int), |
635 | .mode = 0644, | |
6d9f239a | 636 | .proc_handler = proc_dointvec_jiffies, |
a999e683 PM |
637 | }, |
638 | { | |
a999e683 | 639 | .procname = "ip_conntrack_sctp_timeout_shutdown_sent", |
86c0bf40 | 640 | .data = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT], |
a999e683 PM |
641 | .maxlen = sizeof(unsigned int), |
642 | .mode = 0644, | |
6d9f239a | 643 | .proc_handler = proc_dointvec_jiffies, |
a999e683 PM |
644 | }, |
645 | { | |
a999e683 | 646 | .procname = "ip_conntrack_sctp_timeout_shutdown_recd", |
86c0bf40 | 647 | .data = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD], |
a999e683 PM |
648 | .maxlen = sizeof(unsigned int), |
649 | .mode = 0644, | |
6d9f239a | 650 | .proc_handler = proc_dointvec_jiffies, |
a999e683 PM |
651 | }, |
652 | { | |
a999e683 | 653 | .procname = "ip_conntrack_sctp_timeout_shutdown_ack_sent", |
86c0bf40 | 654 | .data = &sctp_timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT], |
a999e683 PM |
655 | .maxlen = sizeof(unsigned int), |
656 | .mode = 0644, | |
6d9f239a | 657 | .proc_handler = proc_dointvec_jiffies, |
a999e683 | 658 | }, |
f8572d8f | 659 | { } |
a999e683 PM |
660 | }; |
661 | #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */ | |
933a41e7 | 662 | #endif |
9fb9cbb1 | 663 | |
61075af5 | 664 | static struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp4 __read_mostly = { |
933a41e7 PM |
665 | .l3proto = PF_INET, |
666 | .l4proto = IPPROTO_SCTP, | |
667 | .name = "sctp", | |
668 | .pkt_to_tuple = sctp_pkt_to_tuple, | |
669 | .invert_tuple = sctp_invert_tuple, | |
670 | .print_tuple = sctp_print_tuple, | |
671 | .print_conntrack = sctp_print_conntrack, | |
672 | .packet = sctp_packet, | |
2c8503f5 | 673 | .get_timeouts = sctp_get_timeouts, |
933a41e7 PM |
674 | .new = sctp_new, |
675 | .me = THIS_MODULE, | |
c0cd1156 | 676 | #if IS_ENABLED(CONFIG_NF_CT_NETLINK) |
a258860e | 677 | .to_nlattr = sctp_to_nlattr, |
a400c30e | 678 | .nlattr_size = sctp_nlattr_size, |
a258860e | 679 | .from_nlattr = nlattr_to_sctp, |
c7212e9d | 680 | .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, |
a400c30e | 681 | .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, |
c7212e9d PNA |
682 | .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, |
683 | .nla_policy = nf_ct_port_nla_policy, | |
684 | #endif | |
933a41e7 PM |
685 | #ifdef CONFIG_SYSCTL |
686 | .ctl_table_users = &sctp_sysctl_table_users, | |
687 | .ctl_table_header = &sctp_sysctl_header, | |
688 | .ctl_table = sctp_sysctl_table, | |
a999e683 PM |
689 | #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT |
690 | .ctl_compat_table = sctp_compat_sysctl_table, | |
691 | #endif | |
933a41e7 | 692 | #endif |
9fb9cbb1 YK |
693 | }; |
694 | ||
61075af5 | 695 | static struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp6 __read_mostly = { |
933a41e7 PM |
696 | .l3proto = PF_INET6, |
697 | .l4proto = IPPROTO_SCTP, | |
698 | .name = "sctp", | |
699 | .pkt_to_tuple = sctp_pkt_to_tuple, | |
700 | .invert_tuple = sctp_invert_tuple, | |
701 | .print_tuple = sctp_print_tuple, | |
702 | .print_conntrack = sctp_print_conntrack, | |
703 | .packet = sctp_packet, | |
2c8503f5 | 704 | .get_timeouts = sctp_get_timeouts, |
933a41e7 PM |
705 | .new = sctp_new, |
706 | .me = THIS_MODULE, | |
c0cd1156 | 707 | #if IS_ENABLED(CONFIG_NF_CT_NETLINK) |
a258860e | 708 | .to_nlattr = sctp_to_nlattr, |
a400c30e | 709 | .nlattr_size = sctp_nlattr_size, |
a258860e | 710 | .from_nlattr = nlattr_to_sctp, |
c7212e9d | 711 | .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, |
a400c30e | 712 | .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, |
c7212e9d PNA |
713 | .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, |
714 | .nla_policy = nf_ct_port_nla_policy, | |
715 | #endif | |
933a41e7 PM |
716 | #ifdef CONFIG_SYSCTL |
717 | .ctl_table_users = &sctp_sysctl_table_users, | |
718 | .ctl_table_header = &sctp_sysctl_header, | |
719 | .ctl_table = sctp_sysctl_table, | |
9fb9cbb1 | 720 | #endif |
933a41e7 | 721 | }; |
9fb9cbb1 | 722 | |
2f0d2f10 | 723 | static int __init nf_conntrack_proto_sctp_init(void) |
9fb9cbb1 YK |
724 | { |
725 | int ret; | |
726 | ||
605dcad6 | 727 | ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_sctp4); |
9fb9cbb1 | 728 | if (ret) { |
654d0fbd | 729 | pr_err("nf_conntrack_l4proto_sctp4: protocol register failed\n"); |
9fb9cbb1 YK |
730 | goto out; |
731 | } | |
605dcad6 | 732 | ret = nf_conntrack_l4proto_register(&nf_conntrack_l4proto_sctp6); |
9fb9cbb1 | 733 | if (ret) { |
654d0fbd | 734 | pr_err("nf_conntrack_l4proto_sctp6: protocol register failed\n"); |
9fb9cbb1 YK |
735 | goto cleanup_sctp4; |
736 | } | |
737 | ||
9fb9cbb1 YK |
738 | return ret; |
739 | ||
9fb9cbb1 | 740 | cleanup_sctp4: |
605dcad6 | 741 | nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_sctp4); |
9fb9cbb1 | 742 | out: |
9fb9cbb1 YK |
743 | return ret; |
744 | } | |
745 | ||
2f0d2f10 | 746 | static void __exit nf_conntrack_proto_sctp_fini(void) |
9fb9cbb1 | 747 | { |
605dcad6 MJ |
748 | nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_sctp6); |
749 | nf_conntrack_l4proto_unregister(&nf_conntrack_l4proto_sctp4); | |
9fb9cbb1 YK |
750 | } |
751 | ||
65b4b4e8 AM |
752 | module_init(nf_conntrack_proto_sctp_init); |
753 | module_exit(nf_conntrack_proto_sctp_fini); | |
9fb9cbb1 YK |
754 | |
755 | MODULE_LICENSE("GPL"); | |
756 | MODULE_AUTHOR("Kiran Kumar Immidi"); | |
757 | MODULE_DESCRIPTION("Netfilter connection tracking protocol helper for SCTP"); | |
d2483dde | 758 | MODULE_ALIAS("ip_conntrack_proto_sctp"); |