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, write to
25 * the Free Software Foundation, 59 Temple Place - Suite 330,
26 * Boston, MA 02111-1307, USA.
28 * Please send any bug reports or fixes you make to the
30 * lksctp developers <lksctp-developers@lists.sourceforge.net>
32 * Or submit a bug report through the following website:
33 * http://www.sf.net/projects/lksctp
35 * Written or modified by:
36 * La Monte H.P. Yarroll <piggy@acm.org>
37 * Karl Knutson <karl@athena.chicago.il.us>
38 * Xingang Guo <xingang.guo@intel.com>
39 * Jon Grimm <jgrimm@us.ibm.com>
40 * Dajiang Zhang <dajiang.zhang@nokia.com>
41 * Sridhar Samudrala <sri@us.ibm.com>
42 * Daisy Chang <daisyc@us.ibm.com>
43 * Ardelle Fan <ardelle.fan@intel.com>
44 * Kevin Gao <kevin.gao@intel.com>
46 * Any bugs reported given to us we will try to fix... any fixes shared will
47 * be incorporated into the next SCTP release.
50 #include <linux/types.h>
51 #include <linux/compiler.h>
52 #include <linux/slab.h>
54 #include <net/sctp/command.h>
55 #include <net/sctp/sctp.h>
61 * Possible values for the disposition are:
64 SCTP_DISPOSITION_DISCARD
, /* No further processing. */
65 SCTP_DISPOSITION_CONSUME
, /* Process return values normally. */
66 SCTP_DISPOSITION_NOMEM
, /* We ran out of memory--recover. */
67 SCTP_DISPOSITION_DELETE_TCB
, /* Close the association. */
68 SCTP_DISPOSITION_ABORT
, /* Close the association NOW. */
69 SCTP_DISPOSITION_VIOLATION
, /* The peer is misbehaving. */
70 SCTP_DISPOSITION_NOT_IMPL
, /* This entry is not implemented. */
71 SCTP_DISPOSITION_ERROR
, /* This is plain old user error. */
72 SCTP_DISPOSITION_BUG
, /* This is a bug. */
80 typedef sctp_disposition_t (sctp_state_fn_t
) (const struct sctp_endpoint
*,
81 const struct sctp_association
*,
82 const sctp_subtype_t type
,
85 typedef void (sctp_timer_event_t
) (unsigned long);
89 } sctp_sm_table_entry_t
;
91 /* A naming convention of "sctp_sf_xxx" applies to all the state functions
95 /* Prototypes for generic state functions. */
96 sctp_state_fn_t sctp_sf_not_impl
;
97 sctp_state_fn_t sctp_sf_bug
;
99 /* Prototypes for gener timer state functions. */
100 sctp_state_fn_t sctp_sf_timer_ignore
;
102 /* Prototypes for chunk state functions. */
103 sctp_state_fn_t sctp_sf_do_9_1_abort
;
104 sctp_state_fn_t sctp_sf_cookie_wait_abort
;
105 sctp_state_fn_t sctp_sf_cookie_echoed_abort
;
106 sctp_state_fn_t sctp_sf_shutdown_pending_abort
;
107 sctp_state_fn_t sctp_sf_shutdown_sent_abort
;
108 sctp_state_fn_t sctp_sf_shutdown_ack_sent_abort
;
109 sctp_state_fn_t sctp_sf_do_5_1B_init
;
110 sctp_state_fn_t sctp_sf_do_5_1C_ack
;
111 sctp_state_fn_t sctp_sf_do_5_1D_ce
;
112 sctp_state_fn_t sctp_sf_do_5_1E_ca
;
113 sctp_state_fn_t sctp_sf_do_4_C
;
114 sctp_state_fn_t sctp_sf_eat_data_6_2
;
115 sctp_state_fn_t sctp_sf_eat_data_fast_4_4
;
116 sctp_state_fn_t sctp_sf_eat_sack_6_2
;
117 sctp_state_fn_t sctp_sf_operr_notify
;
118 sctp_state_fn_t sctp_sf_t1_init_timer_expire
;
119 sctp_state_fn_t sctp_sf_t1_cookie_timer_expire
;
120 sctp_state_fn_t sctp_sf_t2_timer_expire
;
121 sctp_state_fn_t sctp_sf_t4_timer_expire
;
122 sctp_state_fn_t sctp_sf_t5_timer_expire
;
123 sctp_state_fn_t sctp_sf_sendbeat_8_3
;
124 sctp_state_fn_t sctp_sf_beat_8_3
;
125 sctp_state_fn_t sctp_sf_backbeat_8_3
;
126 sctp_state_fn_t sctp_sf_do_9_2_final
;
127 sctp_state_fn_t sctp_sf_do_9_2_shutdown
;
128 sctp_state_fn_t sctp_sf_do_9_2_shut_ctsn
;
129 sctp_state_fn_t sctp_sf_do_ecn_cwr
;
130 sctp_state_fn_t sctp_sf_do_ecne
;
131 sctp_state_fn_t sctp_sf_ootb
;
132 sctp_state_fn_t sctp_sf_pdiscard
;
133 sctp_state_fn_t sctp_sf_violation
;
134 sctp_state_fn_t sctp_sf_discard_chunk
;
135 sctp_state_fn_t sctp_sf_do_5_2_1_siminit
;
136 sctp_state_fn_t sctp_sf_do_5_2_2_dupinit
;
137 sctp_state_fn_t sctp_sf_do_5_2_3_initack
;
138 sctp_state_fn_t sctp_sf_do_5_2_4_dupcook
;
139 sctp_state_fn_t sctp_sf_unk_chunk
;
140 sctp_state_fn_t sctp_sf_do_8_5_1_E_sa
;
141 sctp_state_fn_t sctp_sf_cookie_echoed_err
;
142 sctp_state_fn_t sctp_sf_do_asconf
;
143 sctp_state_fn_t sctp_sf_do_asconf_ack
;
144 sctp_state_fn_t sctp_sf_do_9_2_reshutack
;
145 sctp_state_fn_t sctp_sf_eat_fwd_tsn
;
146 sctp_state_fn_t sctp_sf_eat_fwd_tsn_fast
;
147 sctp_state_fn_t sctp_sf_eat_auth
;
149 /* Prototypes for primitive event state functions. */
150 sctp_state_fn_t sctp_sf_do_prm_asoc
;
151 sctp_state_fn_t sctp_sf_do_prm_send
;
152 sctp_state_fn_t sctp_sf_do_9_2_prm_shutdown
;
153 sctp_state_fn_t sctp_sf_cookie_wait_prm_shutdown
;
154 sctp_state_fn_t sctp_sf_cookie_echoed_prm_shutdown
;
155 sctp_state_fn_t sctp_sf_do_9_1_prm_abort
;
156 sctp_state_fn_t sctp_sf_cookie_wait_prm_abort
;
157 sctp_state_fn_t sctp_sf_cookie_echoed_prm_abort
;
158 sctp_state_fn_t sctp_sf_shutdown_pending_prm_abort
;
159 sctp_state_fn_t sctp_sf_shutdown_sent_prm_abort
;
160 sctp_state_fn_t sctp_sf_shutdown_ack_sent_prm_abort
;
161 sctp_state_fn_t sctp_sf_error_closed
;
162 sctp_state_fn_t sctp_sf_error_shutdown
;
163 sctp_state_fn_t sctp_sf_ignore_primitive
;
164 sctp_state_fn_t sctp_sf_do_prm_requestheartbeat
;
165 sctp_state_fn_t sctp_sf_do_prm_asconf
;
167 /* Prototypes for other event state functions. */
168 sctp_state_fn_t sctp_sf_do_9_2_start_shutdown
;
169 sctp_state_fn_t sctp_sf_do_9_2_shutdown_ack
;
170 sctp_state_fn_t sctp_sf_ignore_other
;
171 sctp_state_fn_t sctp_sf_cookie_wait_icmp_abort
;
173 /* Prototypes for timeout event state functions. */
174 sctp_state_fn_t sctp_sf_do_6_3_3_rtx
;
175 sctp_state_fn_t sctp_sf_do_6_2_sack
;
176 sctp_state_fn_t sctp_sf_autoclose_timer_expire
;
178 /* Prototypes for utility support functions. */
179 __u8
sctp_get_chunk_type(struct sctp_chunk
*chunk
);
180 const sctp_sm_table_entry_t
*sctp_sm_lookup_event(sctp_event_t
,
183 int sctp_chunk_iif(const struct sctp_chunk
*);
184 struct sctp_association
*sctp_make_temp_asoc(const struct sctp_endpoint
*,
187 __u32
sctp_generate_verification_tag(void);
188 void sctp_populate_tie_tags(__u8
*cookie
, __u32 curTag
, __u32 hisTag
);
190 /* Prototypes for chunk-building functions. */
191 struct sctp_chunk
*sctp_make_init(const struct sctp_association
*,
192 const struct sctp_bind_addr
*,
193 gfp_t gfp
, int vparam_len
);
194 struct sctp_chunk
*sctp_make_init_ack(const struct sctp_association
*,
195 const struct sctp_chunk
*,
197 const int unkparam_len
);
198 struct sctp_chunk
*sctp_make_cookie_echo(const struct sctp_association
*,
199 const struct sctp_chunk
*);
200 struct sctp_chunk
*sctp_make_cookie_ack(const struct sctp_association
*,
201 const struct sctp_chunk
*);
202 struct sctp_chunk
*sctp_make_cwr(const struct sctp_association
*,
203 const __u32 lowest_tsn
,
204 const struct sctp_chunk
*);
205 struct sctp_chunk
* sctp_make_datafrag_empty(struct sctp_association
*,
206 const struct sctp_sndrcvinfo
*sinfo
,
207 int len
, const __u8 flags
,
209 struct sctp_chunk
*sctp_make_ecne(const struct sctp_association
*,
211 struct sctp_chunk
*sctp_make_sack(const struct sctp_association
*);
212 struct sctp_chunk
*sctp_make_shutdown(const struct sctp_association
*asoc
,
213 const struct sctp_chunk
*chunk
);
214 struct sctp_chunk
*sctp_make_shutdown_ack(const struct sctp_association
*asoc
,
215 const struct sctp_chunk
*);
216 struct sctp_chunk
*sctp_make_shutdown_complete(const struct sctp_association
*,
217 const struct sctp_chunk
*);
218 void sctp_init_cause(struct sctp_chunk
*, __be16 cause
, size_t);
219 struct sctp_chunk
*sctp_make_abort(const struct sctp_association
*,
220 const struct sctp_chunk
*,
222 struct sctp_chunk
*sctp_make_abort_no_data(const struct sctp_association
*,
223 const struct sctp_chunk
*,
225 struct sctp_chunk
*sctp_make_abort_user(const struct sctp_association
*,
226 const struct msghdr
*, size_t msg_len
);
227 struct sctp_chunk
*sctp_make_abort_violation(const struct sctp_association
*,
228 const struct sctp_chunk
*,
231 struct sctp_chunk
*sctp_make_violation_paramlen(const struct sctp_association
*,
232 const struct sctp_chunk
*,
233 struct sctp_paramhdr
*);
234 struct sctp_chunk
*sctp_make_heartbeat(const struct sctp_association
*,
235 const struct sctp_transport
*,
237 const size_t paylen
);
238 struct sctp_chunk
*sctp_make_heartbeat_ack(const struct sctp_association
*,
239 const struct sctp_chunk
*,
241 const size_t paylen
);
242 struct sctp_chunk
*sctp_make_op_error(const struct sctp_association
*,
243 const struct sctp_chunk
*chunk
,
247 size_t reserve_tail
);
249 struct sctp_chunk
*sctp_make_asconf_update_ip(struct sctp_association
*,
253 struct sctp_chunk
*sctp_make_asconf_set_prim(struct sctp_association
*asoc
,
254 union sctp_addr
*addr
);
255 int sctp_verify_asconf(const struct sctp_association
*asoc
,
256 struct sctp_paramhdr
*param_hdr
, void *chunk_end
,
257 struct sctp_paramhdr
**errp
);
258 struct sctp_chunk
*sctp_process_asconf(struct sctp_association
*asoc
,
259 struct sctp_chunk
*asconf
);
260 int sctp_process_asconf_ack(struct sctp_association
*asoc
,
261 struct sctp_chunk
*asconf_ack
);
262 struct sctp_chunk
*sctp_make_fwdtsn(const struct sctp_association
*asoc
,
263 __u32 new_cum_tsn
, size_t nstreams
,
264 struct sctp_fwdtsn_skip
*skiplist
);
265 struct sctp_chunk
*sctp_make_auth(const struct sctp_association
*asoc
);
267 void sctp_chunk_assign_tsn(struct sctp_chunk
*);
268 void sctp_chunk_assign_ssn(struct sctp_chunk
*);
270 /* Prototypes for statetable processing. */
272 int sctp_do_sm(sctp_event_t event_type
, sctp_subtype_t subtype
,
274 struct sctp_endpoint
*,
275 struct sctp_association
*asoc
,
279 /* 2nd level prototypes */
280 void sctp_generate_t3_rtx_event(unsigned long peer
);
281 void sctp_generate_heartbeat_event(unsigned long peer
);
283 void sctp_ootb_pkt_free(struct sctp_packet
*);
285 struct sctp_association
*sctp_unpack_cookie(const struct sctp_endpoint
*,
286 const struct sctp_association
*,
289 struct sctp_chunk
**err_chk_p
);
290 int sctp_addip_addr_config(struct sctp_association
*, sctp_param_t
,
291 struct sockaddr_storage
*, int);
293 /* 3rd level prototypes */
294 __u32
sctp_generate_tag(const struct sctp_endpoint
*);
295 __u32
sctp_generate_tsn(const struct sctp_endpoint
*);
297 /* Extern declarations for major data structures. */
298 extern sctp_timer_event_t
*sctp_timer_events
[SCTP_NUM_TIMEOUT_TYPES
];
301 /* Get the size of a DATA chunk payload. */
302 static inline __u16
sctp_data_size(struct sctp_chunk
*chunk
)
306 size
= ntohs(chunk
->chunk_hdr
->length
);
307 size
-= sizeof(sctp_data_chunk_t
);
312 /* Compare two TSNs */
314 /* RFC 1982 - Serial Number Arithmetic
317 * Then, s1 is said to be equal to s2 if and only if i1 is equal to i2,
318 * in all other cases, s1 is not equal to s2.
320 * s1 is said to be less than s2 if, and only if, s1 is not equal to s2,
323 * (i1 < i2 and i2 - i1 < 2^(SERIAL_BITS - 1)) or
324 * (i1 > i2 and i1 - i2 > 2^(SERIAL_BITS - 1))
326 * s1 is said to be greater than s2 if, and only if, s1 is not equal to
329 * (i1 < i2 and i2 - i1 > 2^(SERIAL_BITS - 1)) or
330 * (i1 > i2 and i1 - i2 < 2^(SERIAL_BITS - 1))
335 * 1.6 Serial Number Arithmetic
337 * Comparisons and arithmetic on TSNs in this document SHOULD use Serial
338 * Number Arithmetic as defined in [RFC1982] where SERIAL_BITS = 32.
342 TSN_SIGN_BIT
= (1<<31)
345 static inline int TSN_lt(__u32 s
, __u32 t
)
347 return (((s
) - (t
)) & TSN_SIGN_BIT
);
350 static inline int TSN_lte(__u32 s
, __u32 t
)
352 return (((s
) == (t
)) || (((s
) - (t
)) & TSN_SIGN_BIT
));
355 /* Compare two SSNs */
359 * 1.6 Serial Number Arithmetic
361 * Comparisons and arithmetic on Stream Sequence Numbers in this document
362 * SHOULD use Serial Number Arithmetic as defined in [RFC1982] where
366 SSN_SIGN_BIT
= (1<<15)
369 static inline int SSN_lt(__u16 s
, __u16 t
)
371 return (((s
) - (t
)) & SSN_SIGN_BIT
);
374 static inline int SSN_lte(__u16 s
, __u16 t
)
376 return (((s
) == (t
)) || (((s
) - (t
)) & SSN_SIGN_BIT
));
381 * The valid range of Serial Number is from 0 to 4294967295 (2**32 - 1). Serial
382 * Numbers wrap back to 0 after reaching 4294967295.
385 ADDIP_SERIAL_SIGN_BIT
= (1<<31)
388 static inline int ADDIP_SERIAL_gte(__u16 s
, __u16 t
)
390 return (((s
) == (t
)) || (((t
) - (s
)) & ADDIP_SERIAL_SIGN_BIT
));
393 /* Check VTAG of the packet matches the sender's own tag. */
395 sctp_vtag_verify(const struct sctp_chunk
*chunk
,
396 const struct sctp_association
*asoc
)
398 /* RFC 2960 Sec 8.5 When receiving an SCTP packet, the endpoint
399 * MUST ensure that the value in the Verification Tag field of
400 * the received SCTP packet matches its own Tag. If the received
401 * Verification Tag value does not match the receiver's own
402 * tag value, the receiver shall silently discard the packet...
404 if (ntohl(chunk
->sctp_hdr
->vtag
) == asoc
->c
.my_vtag
)
410 /* Check VTAG of the packet matches the sender's own tag and the T bit is
411 * not set, OR its peer's tag and the T bit is set in the Chunk Flags.
414 sctp_vtag_verify_either(const struct sctp_chunk
*chunk
,
415 const struct sctp_association
*asoc
)
417 /* RFC 2960 Section 8.5.1, sctpimpguide Section 2.41
419 * B) The receiver of a ABORT MUST accept the packet
420 * if the Verification Tag field of the packet matches its own tag
421 * and the T bit is not set
423 * it is set to its peer's tag and the T bit is set in the Chunk
425 * Otherwise, the receiver MUST silently discard the packet
426 * and take no further action.
428 * C) The receiver of a SHUTDOWN COMPLETE shall accept the packet
429 * if the Verification Tag field of the packet matches its own tag
430 * and the T bit is not set
432 * it is set to its peer's tag and the T bit is set in the Chunk
434 * Otherwise, the receiver MUST silently discard the packet
435 * and take no further action. An endpoint MUST ignore the
436 * SHUTDOWN COMPLETE if it is not in the SHUTDOWN-ACK-SENT state.
438 if ((!sctp_test_T_bit(chunk
) &&
439 (ntohl(chunk
->sctp_hdr
->vtag
) == asoc
->c
.my_vtag
)) ||
440 (sctp_test_T_bit(chunk
) &&
441 (ntohl(chunk
->sctp_hdr
->vtag
) == asoc
->c
.peer_vtag
))) {
448 #endif /* __sctp_sm_h__ */