1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001 Intel Corp.
7 * This file is part of the SCTP kernel implementation
9 * These are definitions needed by the state machine.
11 * This SCTP implementation is free software;
12 * you can redistribute it and/or modify it under the terms of
13 * the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
17 * This SCTP implementation is distributed in the hope that it
18 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19 * ************************
20 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21 * See the GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with GNU CC; see the file COPYING. If not, see
25 * <http://www.gnu.org/licenses/>.
27 * Please send any bug reports or fixes you make to the
29 * lksctp developers <linux-sctp@vger.kernel.org>
31 * Written or modified by:
32 * La Monte H.P. Yarroll <piggy@acm.org>
33 * Karl Knutson <karl@athena.chicago.il.us>
34 * Xingang Guo <xingang.guo@intel.com>
35 * Jon Grimm <jgrimm@us.ibm.com>
36 * Dajiang Zhang <dajiang.zhang@nokia.com>
37 * Sridhar Samudrala <sri@us.ibm.com>
38 * Daisy Chang <daisyc@us.ibm.com>
39 * Ardelle Fan <ardelle.fan@intel.com>
40 * Kevin Gao <kevin.gao@intel.com>
43 #include <linux/types.h>
44 #include <linux/compiler.h>
45 #include <linux/slab.h>
47 #include <net/sctp/command.h>
48 #include <net/sctp/sctp.h>
54 * Possible values for the disposition are:
57 SCTP_DISPOSITION_DISCARD, /* No further processing. */
58 SCTP_DISPOSITION_CONSUME, /* Process return values normally. */
59 SCTP_DISPOSITION_NOMEM, /* We ran out of memory--recover. */
60 SCTP_DISPOSITION_DELETE_TCB, /* Close the association. */
61 SCTP_DISPOSITION_ABORT, /* Close the association NOW. */
62 SCTP_DISPOSITION_VIOLATION, /* The peer is misbehaving. */
63 SCTP_DISPOSITION_NOT_IMPL, /* This entry is not implemented. */
64 SCTP_DISPOSITION_ERROR, /* This is plain old user error. */
65 SCTP_DISPOSITION_BUG, /* This is a bug. */
73 typedef sctp_disposition_t (sctp_state_fn_t) (struct net *,
74 const struct sctp_endpoint *,
75 const struct sctp_association *,
76 const sctp_subtype_t type,
79 typedef void (sctp_timer_event_t) (unsigned long);
83 } sctp_sm_table_entry_t;
85 /* A naming convention of "sctp_sf_xxx" applies to all the state functions
89 /* Prototypes for generic state functions. */
90 sctp_state_fn_t sctp_sf_not_impl;
91 sctp_state_fn_t sctp_sf_bug;
93 /* Prototypes for gener timer state functions. */
94 sctp_state_fn_t sctp_sf_timer_ignore;
96 /* Prototypes for chunk state functions. */
97 sctp_state_fn_t sctp_sf_do_9_1_abort;
98 sctp_state_fn_t sctp_sf_cookie_wait_abort;
99 sctp_state_fn_t sctp_sf_cookie_echoed_abort;
100 sctp_state_fn_t sctp_sf_shutdown_pending_abort;
101 sctp_state_fn_t sctp_sf_shutdown_sent_abort;
102 sctp_state_fn_t sctp_sf_shutdown_ack_sent_abort;
103 sctp_state_fn_t sctp_sf_do_5_1B_init;
104 sctp_state_fn_t sctp_sf_do_5_1C_ack;
105 sctp_state_fn_t sctp_sf_do_5_1D_ce;
106 sctp_state_fn_t sctp_sf_do_5_1E_ca;
107 sctp_state_fn_t sctp_sf_do_4_C;
108 sctp_state_fn_t sctp_sf_eat_data_6_2;
109 sctp_state_fn_t sctp_sf_eat_data_fast_4_4;
110 sctp_state_fn_t sctp_sf_eat_sack_6_2;
111 sctp_state_fn_t sctp_sf_operr_notify;
112 sctp_state_fn_t sctp_sf_t1_init_timer_expire;
113 sctp_state_fn_t sctp_sf_t1_cookie_timer_expire;
114 sctp_state_fn_t sctp_sf_t2_timer_expire;
115 sctp_state_fn_t sctp_sf_t4_timer_expire;
116 sctp_state_fn_t sctp_sf_t5_timer_expire;
117 sctp_state_fn_t sctp_sf_sendbeat_8_3;
118 sctp_state_fn_t sctp_sf_beat_8_3;
119 sctp_state_fn_t sctp_sf_backbeat_8_3;
120 sctp_state_fn_t sctp_sf_do_9_2_final;
121 sctp_state_fn_t sctp_sf_do_9_2_shutdown;
122 sctp_state_fn_t sctp_sf_do_9_2_shut_ctsn;
123 sctp_state_fn_t sctp_sf_do_ecn_cwr;
124 sctp_state_fn_t sctp_sf_do_ecne;
125 sctp_state_fn_t sctp_sf_ootb;
126 sctp_state_fn_t sctp_sf_pdiscard;
127 sctp_state_fn_t sctp_sf_violation;
128 sctp_state_fn_t sctp_sf_discard_chunk;
129 sctp_state_fn_t sctp_sf_do_5_2_1_siminit;
130 sctp_state_fn_t sctp_sf_do_5_2_2_dupinit;
131 sctp_state_fn_t sctp_sf_do_5_2_3_initack;
132 sctp_state_fn_t sctp_sf_do_5_2_4_dupcook;
133 sctp_state_fn_t sctp_sf_unk_chunk;
134 sctp_state_fn_t sctp_sf_do_8_5_1_E_sa;
135 sctp_state_fn_t sctp_sf_cookie_echoed_err;
136 sctp_state_fn_t sctp_sf_do_asconf;
137 sctp_state_fn_t sctp_sf_do_asconf_ack;
138 sctp_state_fn_t sctp_sf_do_9_2_reshutack;
139 sctp_state_fn_t sctp_sf_eat_fwd_tsn;
140 sctp_state_fn_t sctp_sf_eat_fwd_tsn_fast;
141 sctp_state_fn_t sctp_sf_eat_auth;
143 /* Prototypes for primitive event state functions. */
144 sctp_state_fn_t sctp_sf_do_prm_asoc;
145 sctp_state_fn_t sctp_sf_do_prm_send;
146 sctp_state_fn_t sctp_sf_do_9_2_prm_shutdown;
147 sctp_state_fn_t sctp_sf_cookie_wait_prm_shutdown;
148 sctp_state_fn_t sctp_sf_cookie_echoed_prm_shutdown;
149 sctp_state_fn_t sctp_sf_do_9_1_prm_abort;
150 sctp_state_fn_t sctp_sf_cookie_wait_prm_abort;
151 sctp_state_fn_t sctp_sf_cookie_echoed_prm_abort;
152 sctp_state_fn_t sctp_sf_shutdown_pending_prm_abort;
153 sctp_state_fn_t sctp_sf_shutdown_sent_prm_abort;
154 sctp_state_fn_t sctp_sf_shutdown_ack_sent_prm_abort;
155 sctp_state_fn_t sctp_sf_error_closed;
156 sctp_state_fn_t sctp_sf_error_shutdown;
157 sctp_state_fn_t sctp_sf_ignore_primitive;
158 sctp_state_fn_t sctp_sf_do_prm_requestheartbeat;
159 sctp_state_fn_t sctp_sf_do_prm_asconf;
160 sctp_state_fn_t sctp_sf_do_prm_reconf;
162 /* Prototypes for other event state functions. */
163 sctp_state_fn_t sctp_sf_do_no_pending_tsn;
164 sctp_state_fn_t sctp_sf_do_9_2_start_shutdown;
165 sctp_state_fn_t sctp_sf_do_9_2_shutdown_ack;
166 sctp_state_fn_t sctp_sf_ignore_other;
167 sctp_state_fn_t sctp_sf_cookie_wait_icmp_abort;
169 /* Prototypes for timeout event state functions. */
170 sctp_state_fn_t sctp_sf_do_6_3_3_rtx;
171 sctp_state_fn_t sctp_sf_send_reconf;
172 sctp_state_fn_t sctp_sf_do_6_2_sack;
173 sctp_state_fn_t sctp_sf_autoclose_timer_expire;
175 /* Prototypes for utility support functions. */
176 __u8 sctp_get_chunk_type(struct sctp_chunk *chunk);
177 const sctp_sm_table_entry_t *sctp_sm_lookup_event(struct net *,
181 int sctp_chunk_iif(const struct sctp_chunk *);
182 struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *,
185 __u32 sctp_generate_verification_tag(void);
186 void sctp_populate_tie_tags(__u8 *cookie, __u32 curTag, __u32 hisTag);
188 /* Prototypes for chunk-building functions. */
189 struct sctp_chunk *sctp_make_init(const struct sctp_association *,
190 const struct sctp_bind_addr *,
191 gfp_t gfp, int vparam_len);
192 struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *,
193 const struct sctp_chunk *,
195 const int unkparam_len);
196 struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *,
197 const struct sctp_chunk *);
198 struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *,
199 const struct sctp_chunk *);
200 struct sctp_chunk *sctp_make_cwr(const struct sctp_association *,
201 const __u32 lowest_tsn,
202 const struct sctp_chunk *);
203 struct sctp_chunk * sctp_make_datafrag_empty(struct sctp_association *,
204 const struct sctp_sndrcvinfo *sinfo,
205 int len, const __u8 flags,
206 __u16 ssn, gfp_t gfp);
207 struct sctp_chunk *sctp_make_ecne(const struct sctp_association *,
209 struct sctp_chunk *sctp_make_sack(const struct sctp_association *);
210 struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc,
211 const struct sctp_chunk *chunk);
212 struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc,
213 const struct sctp_chunk *);
214 struct sctp_chunk *sctp_make_shutdown_complete(const struct sctp_association *,
215 const struct sctp_chunk *);
216 void sctp_init_cause(struct sctp_chunk *, __be16 cause, size_t);
217 struct sctp_chunk *sctp_make_abort(const struct sctp_association *,
218 const struct sctp_chunk *,
220 struct sctp_chunk *sctp_make_abort_no_data(const struct sctp_association *,
221 const struct sctp_chunk *,
223 struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *,
224 struct msghdr *, size_t msg_len);
225 struct sctp_chunk *sctp_make_abort_violation(const struct sctp_association *,
226 const struct sctp_chunk *,
229 struct sctp_chunk *sctp_make_violation_paramlen(const struct sctp_association *,
230 const struct sctp_chunk *,
231 struct sctp_paramhdr *);
232 struct sctp_chunk *sctp_make_violation_max_retrans(const struct sctp_association *,
233 const struct sctp_chunk *);
234 struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *,
235 const struct sctp_transport *);
236 struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *,
237 const struct sctp_chunk *,
239 const size_t paylen);
240 struct sctp_chunk *sctp_make_op_error(const struct sctp_association *,
241 const struct sctp_chunk *chunk,
245 size_t reserve_tail);
247 struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *,
251 struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc,
252 union sctp_addr *addr);
253 bool sctp_verify_asconf(const struct sctp_association *asoc,
254 struct sctp_chunk *chunk, bool addr_param_needed,
255 struct sctp_paramhdr **errp);
256 struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc,
257 struct sctp_chunk *asconf);
258 int sctp_process_asconf_ack(struct sctp_association *asoc,
259 struct sctp_chunk *asconf_ack);
260 struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
261 __u32 new_cum_tsn, size_t nstreams,
262 struct sctp_fwdtsn_skip *skiplist);
263 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc);
264 struct sctp_chunk *sctp_make_strreset_req(
265 const struct sctp_association *asoc,
266 __u16 stream_num, __u16 *stream_list,
268 struct sctp_chunk *sctp_make_strreset_tsnreq(
269 const struct sctp_association *asoc);
270 struct sctp_chunk *sctp_make_strreset_addstrm(
271 const struct sctp_association *asoc,
272 __u16 out, __u16 in);
273 void sctp_chunk_assign_tsn(struct sctp_chunk *);
274 void sctp_chunk_assign_ssn(struct sctp_chunk *);
276 /* Prototypes for statetable processing. */
278 int sctp_do_sm(struct net *net, sctp_event_t event_type, sctp_subtype_t subtype,
280 struct sctp_endpoint *,
281 struct sctp_association *asoc,
285 /* 2nd level prototypes */
286 void sctp_generate_t3_rtx_event(unsigned long peer);
287 void sctp_generate_heartbeat_event(unsigned long peer);
288 void sctp_generate_reconf_event(unsigned long peer);
289 void sctp_generate_proto_unreach_event(unsigned long peer);
291 void sctp_ootb_pkt_free(struct sctp_packet *);
293 struct sctp_association *sctp_unpack_cookie(const struct sctp_endpoint *,
294 const struct sctp_association *,
297 struct sctp_chunk **err_chk_p);
298 int sctp_addip_addr_config(struct sctp_association *, sctp_param_t,
299 struct sockaddr_storage*, int);
301 /* 3rd level prototypes */
302 __u32 sctp_generate_tag(const struct sctp_endpoint *);
303 __u32 sctp_generate_tsn(const struct sctp_endpoint *);
305 /* Extern declarations for major data structures. */
306 extern sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES];
309 /* Get the size of a DATA chunk payload. */
310 static inline __u16 sctp_data_size(struct sctp_chunk *chunk)
314 size = ntohs(chunk->chunk_hdr->length);
315 size -= sizeof(sctp_data_chunk_t);
320 /* Compare two TSNs */
321 #define TSN_lt(a,b) \
322 (typecheck(__u32, a) && \
323 typecheck(__u32, b) && \
324 ((__s32)((a) - (b)) < 0))
326 #define TSN_lte(a,b) \
327 (typecheck(__u32, a) && \
328 typecheck(__u32, b) && \
329 ((__s32)((a) - (b)) <= 0))
331 /* Compare two SSNs */
332 #define SSN_lt(a,b) \
333 (typecheck(__u16, a) && \
334 typecheck(__u16, b) && \
335 ((__s16)((a) - (b)) < 0))
338 #define ADDIP_SERIAL_gte(a,b) \
339 (typecheck(__u32, a) && \
340 typecheck(__u32, b) && \
341 ((__s32)((b) - (a)) <= 0))
343 /* Check VTAG of the packet matches the sender's own tag. */
345 sctp_vtag_verify(const struct sctp_chunk *chunk,
346 const struct sctp_association *asoc)
348 /* RFC 2960 Sec 8.5 When receiving an SCTP packet, the endpoint
349 * MUST ensure that the value in the Verification Tag field of
350 * the received SCTP packet matches its own Tag. If the received
351 * Verification Tag value does not match the receiver's own
352 * tag value, the receiver shall silently discard the packet...
354 if (ntohl(chunk->sctp_hdr->vtag) == asoc->c.my_vtag)
360 /* Check VTAG of the packet matches the sender's own tag and the T bit is
361 * not set, OR its peer's tag and the T bit is set in the Chunk Flags.
364 sctp_vtag_verify_either(const struct sctp_chunk *chunk,
365 const struct sctp_association *asoc)
367 /* RFC 2960 Section 8.5.1, sctpimpguide Section 2.41
369 * B) The receiver of a ABORT MUST accept the packet
370 * if the Verification Tag field of the packet matches its own tag
371 * and the T bit is not set
373 * it is set to its peer's tag and the T bit is set in the Chunk
375 * Otherwise, the receiver MUST silently discard the packet
376 * and take no further action.
378 * C) The receiver of a SHUTDOWN COMPLETE shall accept the packet
379 * if the Verification Tag field of the packet matches its own tag
380 * and the T bit is not set
382 * it is set to its peer's tag and the T bit is set in the Chunk
384 * Otherwise, the receiver MUST silently discard the packet
385 * and take no further action. An endpoint MUST ignore the
386 * SHUTDOWN COMPLETE if it is not in the SHUTDOWN-ACK-SENT state.
388 if ((!sctp_test_T_bit(chunk) &&
389 (ntohl(chunk->sctp_hdr->vtag) == asoc->c.my_vtag)) ||
390 (sctp_test_T_bit(chunk) && asoc->c.peer_vtag &&
391 (ntohl(chunk->sctp_hdr->vtag) == asoc->c.peer_vtag))) {
398 #endif /* __sctp_sm_h__ */