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 * This SCTP implementation is free software;
10 * you can redistribute it and/or modify it under the terms of
11 * the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
15 * This SCTP implementation is distributed in the hope that it
16 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
17 * ************************
18 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
19 * See the GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with GNU CC; see the file COPYING. If not, see
23 * <http://www.gnu.org/licenses/>.
25 * Please send any bug reports or fixes you make to the
27 * lksctp developers <linux-sctp@vger.kernel.org>
29 * Written or modified by:
30 * La Monte H.P. Yarroll <piggy@acm.org>
31 * Karl Knutson <karl@athena.chicago.il.us>
32 * Randall Stewart <randall@stewart.chicago.il.us>
33 * Ken Morneau <kmorneau@cisco.com>
34 * Qiaobing Xie <qxie1@motorola.com>
35 * Xingang Guo <xingang.guo@intel.com>
36 * Sridhar Samudrala <samudrala@us.ibm.com>
37 * Daisy Chang <daisyc@us.ibm.com>
40 #ifndef __sctp_constants_h__
41 #define __sctp_constants_h__
43 #include <linux/sctp.h>
44 #include <linux/ipv6.h> /* For ipv6hdr. */
45 #include <net/tcp_states.h> /* For TCP states used in enum sctp_sock_state */
47 /* Value used for stream negotiation. */
48 enum { SCTP_MAX_STREAM = 0xffff };
49 enum { SCTP_DEFAULT_OUTSTREAMS = 10 };
50 enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM };
52 /* Since CIDs are sparse, we need all four of the following
53 * symbols. CIDs are dense through SCTP_CID_BASE_MAX.
55 #define SCTP_CID_BASE_MAX SCTP_CID_SHUTDOWN_COMPLETE
57 #define SCTP_NUM_BASE_CHUNK_TYPES (SCTP_CID_BASE_MAX + 1)
59 #define SCTP_NUM_ADDIP_CHUNK_TYPES 2
61 #define SCTP_NUM_PRSCTP_CHUNK_TYPES 1
63 #define SCTP_NUM_RECONF_CHUNK_TYPES 1
65 #define SCTP_NUM_AUTH_CHUNK_TYPES 1
67 #define SCTP_NUM_CHUNK_TYPES (SCTP_NUM_BASE_CHUNK_TYPES + \
68 SCTP_NUM_ADDIP_CHUNK_TYPES +\
69 SCTP_NUM_PRSCTP_CHUNK_TYPES +\
70 SCTP_NUM_RECONF_CHUNK_TYPES +\
71 SCTP_NUM_AUTH_CHUNK_TYPES)
73 /* These are the different flavours of event. */
76 SCTP_EVENT_T_CHUNK = 1,
79 SCTP_EVENT_T_PRIMITIVE
83 /* As a convenience for the state machine, we append SCTP_EVENT_* and
84 * SCTP_ULP_* to the list of possible chunks.
88 SCTP_EVENT_TIMEOUT_NONE = 0,
89 SCTP_EVENT_TIMEOUT_T1_COOKIE,
90 SCTP_EVENT_TIMEOUT_T1_INIT,
91 SCTP_EVENT_TIMEOUT_T2_SHUTDOWN,
92 SCTP_EVENT_TIMEOUT_T3_RTX,
93 SCTP_EVENT_TIMEOUT_T4_RTO,
94 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD,
95 SCTP_EVENT_TIMEOUT_HEARTBEAT,
96 SCTP_EVENT_TIMEOUT_RECONF,
97 SCTP_EVENT_TIMEOUT_SACK,
98 SCTP_EVENT_TIMEOUT_AUTOCLOSE,
99 } sctp_event_timeout_t;
101 #define SCTP_EVENT_TIMEOUT_MAX SCTP_EVENT_TIMEOUT_AUTOCLOSE
102 #define SCTP_NUM_TIMEOUT_TYPES (SCTP_EVENT_TIMEOUT_MAX + 1)
105 SCTP_EVENT_NO_PENDING_TSN = 0,
106 SCTP_EVENT_ICMP_PROTO_UNREACH,
107 } sctp_event_other_t;
109 #define SCTP_EVENT_OTHER_MAX SCTP_EVENT_ICMP_PROTO_UNREACH
110 #define SCTP_NUM_OTHER_TYPES (SCTP_EVENT_OTHER_MAX + 1)
112 /* These are primitive requests from the ULP. */
114 SCTP_PRIMITIVE_ASSOCIATE = 0,
115 SCTP_PRIMITIVE_SHUTDOWN,
116 SCTP_PRIMITIVE_ABORT,
118 SCTP_PRIMITIVE_REQUESTHEARTBEAT,
119 SCTP_PRIMITIVE_ASCONF,
120 SCTP_PRIMITIVE_RECONF,
121 } sctp_event_primitive_t;
123 #define SCTP_EVENT_PRIMITIVE_MAX SCTP_PRIMITIVE_RECONF
124 #define SCTP_NUM_PRIMITIVE_TYPES (SCTP_EVENT_PRIMITIVE_MAX + 1)
126 /* We define here a utility type for manipulating subtypes.
127 * The subtype constructors all work like this:
129 * sctp_subtype_t foo = SCTP_ST_CHUNK(SCTP_CID_INIT);
134 sctp_event_timeout_t timeout;
135 sctp_event_other_t other;
136 sctp_event_primitive_t primitive;
139 #define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \
140 static inline sctp_subtype_t \
141 SCTP_ST_## _name (_type _arg) \
142 { sctp_subtype_t _retval; _retval._elt = _arg; return _retval; }
144 SCTP_SUBTYPE_CONSTRUCTOR(CHUNK, enum sctp_cid, chunk)
145 SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT, sctp_event_timeout_t, timeout)
146 SCTP_SUBTYPE_CONSTRUCTOR(OTHER, sctp_event_other_t, other)
147 SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE, sctp_event_primitive_t, primitive)
150 #define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA)
152 /* Calculate the actual data size in a data chunk */
153 #define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end)\
154 - (unsigned long)(c->chunk_hdr)\
155 - sizeof(struct sctp_data_chunk)))
157 /* Internal error codes */
159 SCTP_IERROR_NO_ERROR = 0,
160 SCTP_IERROR_BASE = 1000,
161 SCTP_IERROR_NO_COOKIE,
163 SCTP_IERROR_STALE_COOKIE,
165 SCTP_IERROR_MALFORMED,
169 SCTP_IERROR_HIGH_TSN,
170 SCTP_IERROR_IGNORE_TSN,
172 SCTP_IERROR_BAD_STREAM,
173 SCTP_IERROR_BAD_PORTS,
174 SCTP_IERROR_AUTH_BAD_HMAC,
175 SCTP_IERROR_AUTH_BAD_KEYID,
176 SCTP_IERROR_PROTO_VIOLATION,
183 /* SCTP state defines for internal state machine */
186 SCTP_STATE_CLOSED = 0,
187 SCTP_STATE_COOKIE_WAIT = 1,
188 SCTP_STATE_COOKIE_ECHOED = 2,
189 SCTP_STATE_ESTABLISHED = 3,
190 SCTP_STATE_SHUTDOWN_PENDING = 4,
191 SCTP_STATE_SHUTDOWN_SENT = 5,
192 SCTP_STATE_SHUTDOWN_RECEIVED = 6,
193 SCTP_STATE_SHUTDOWN_ACK_SENT = 7,
197 #define SCTP_STATE_MAX SCTP_STATE_SHUTDOWN_ACK_SENT
198 #define SCTP_STATE_NUM_STATES (SCTP_STATE_MAX + 1)
200 /* These are values for sk->state.
201 * For a UDP-style SCTP socket, the states are defined as follows
202 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
203 * accept new associations, but it can initiate the creation of new ones.
204 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
205 * accept new associations and can initiate the creation of new ones.
206 * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off
207 * socket with one association.
208 * For a TCP-style SCTP socket, the states are defined as follows
209 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
210 * accept new associations, but it can initiate the creation of new ones.
211 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
212 * accept new associations, but cannot initiate the creation of new ones.
213 * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single
216 enum sctp_sock_state {
217 SCTP_SS_CLOSED = TCP_CLOSE,
218 SCTP_SS_LISTENING = TCP_LISTEN,
219 SCTP_SS_ESTABLISHING = TCP_SYN_SENT,
220 SCTP_SS_ESTABLISHED = TCP_ESTABLISHED,
221 SCTP_SS_CLOSING = TCP_CLOSE_WAIT,
224 /* These functions map various type to printable names. */
225 const char *sctp_cname(const sctp_subtype_t); /* chunk types */
226 const char *sctp_oname(const sctp_subtype_t); /* other events */
227 const char *sctp_tname(const sctp_subtype_t); /* timeouts */
228 const char *sctp_pname(const sctp_subtype_t); /* primitives */
230 /* This is a table of printable names of sctp_state_t's. */
231 extern const char *const sctp_state_tbl[];
232 extern const char *const sctp_evttype_tbl[];
233 extern const char *const sctp_status_tbl[];
235 /* Maximum chunk length considering padding requirements. */
236 enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) };
238 /* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little
239 * harder (until reaching ESTABLISHED state).
241 enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 };
243 /* Guess at how big to make the TSN mapping array.
244 * We guarantee that we can handle at least this big a gap between the
245 * cumulative ACK and the highest TSN. In practice, we can often
246 * handle up to twice this value.
248 * NEVER make this more than 32767 (2^15-1). The Gap Ack Blocks in a
249 * SACK (see section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE
250 * must be less than 65535 (2^16 - 1), or we will have overflow
251 * problems creating SACK's.
253 #define SCTP_TSN_MAP_INITIAL BITS_PER_LONG
254 #define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL
255 #define SCTP_TSN_MAP_SIZE 4096
257 /* We will not record more than this many duplicate TSNs between two
258 * SACKs. The minimum PMTU is 576. Remove all the headers and there
259 * is enough room for 131 duplicate reports. Round down to the
260 * nearest power of 2.
262 enum { SCTP_MIN_PMTU = 576 };
263 enum { SCTP_MAX_DUP_TSNS = 16 };
264 enum { SCTP_MAX_GABS = 16 };
266 /* Heartbeat interval - 30 secs */
267 #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT (30*1000)
269 /* Delayed sack timer - 200ms */
270 #define SCTP_DEFAULT_TIMEOUT_SACK (200)
272 /* RTO.Initial - 3 seconds
274 * RTO.Max - 60 seconds
278 #define SCTP_RTO_INITIAL (3 * 1000)
279 #define SCTP_RTO_MIN (1 * 1000)
280 #define SCTP_RTO_MAX (60 * 1000)
282 #define SCTP_RTO_ALPHA 3 /* 1/8 when converted to right shifts. */
283 #define SCTP_RTO_BETA 2 /* 1/4 when converted to right shifts. */
285 /* Maximum number of new data packets that can be sent in a burst. */
286 #define SCTP_DEFAULT_MAX_BURST 4
288 #define SCTP_CLOCK_GRANULARITY 1 /* 1 jiffy */
290 #define SCTP_DEFAULT_COOKIE_LIFE (60 * 1000) /* 60 seconds */
292 #define SCTP_DEFAULT_MINWINDOW 1500 /* default minimum rwnd size */
293 #define SCTP_DEFAULT_MAXWINDOW 65535 /* default rwnd size */
294 #define SCTP_DEFAULT_RWND_SHIFT 4 /* by default, update on 1/16 of
295 * rcvbuf, which is 1/8 of initial
298 #define SCTP_DEFAULT_MAXSEGMENT 1500 /* MTU size, this is the limit
299 * to which we will raise the P-MTU.
301 #define SCTP_DEFAULT_MINSEGMENT 512 /* MTU size ... if no mtu disc */
303 #define SCTP_SECRET_SIZE 32 /* Number of octets in a 256 bits. */
305 #define SCTP_SIGNATURE_SIZE 20 /* size of a SLA-1 signature */
307 #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash
308 * functions simpler to write.
311 /* These return values describe the success or failure of a number of
312 * routines which form the lower interface to SCTP_outqueue.
321 /* These are the commands for manipulating transports. */
322 enum sctp_transport_cmd {
328 /* These are the address scopes defined mainly for IPv4 addresses
329 * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
330 * These scopes are hopefully generic enough to be used on scoping both
331 * IPv4 and IPv6 addresses in SCTP.
332 * At this point, the IPv6 scopes will be mapped to these internal scopes
333 * as much as possible.
336 SCTP_SCOPE_GLOBAL, /* IPv4 global addresses */
337 SCTP_SCOPE_PRIVATE, /* IPv4 private addresses */
338 SCTP_SCOPE_LINK, /* IPv4 link local address */
339 SCTP_SCOPE_LOOPBACK, /* IPv4 loopback address */
340 SCTP_SCOPE_UNUSABLE, /* IPv4 unusable addresses */
344 SCTP_SCOPE_POLICY_DISABLE, /* Disable IPv4 address scoping */
345 SCTP_SCOPE_POLICY_ENABLE, /* Enable IPv4 address scoping */
346 SCTP_SCOPE_POLICY_PRIVATE, /* Follow draft but allow IPv4 private addresses */
347 SCTP_SCOPE_POLICY_LINK, /* Follow draft but allow IPv4 link local addresses */
350 #define SCTP_SCOPE_POLICY_MAX SCTP_SCOPE_POLICY_LINK
352 /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>,
353 * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24,
355 * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP
358 #define IS_IPV4_UNUSABLE_ADDRESS(a) \
359 ((htonl(INADDR_BROADCAST) == a) || \
360 ipv4_is_multicast(a) || \
361 ipv4_is_zeronet(a) || \
362 ipv4_is_test_198(a) || \
363 ipv4_is_anycast_6to4(a))
365 /* Flags used for the bind address copy functions. */
366 #define SCTP_ADDR6_ALLOWED 0x00000001 /* IPv6 address is allowed by
368 #define SCTP_ADDR4_PEERSUPP 0x00000002 /* IPv4 address is supported by
370 #define SCTP_ADDR6_PEERSUPP 0x00000004 /* IPv6 address is supported by
373 /* Reasons to retransmit. */
374 enum sctp_retransmit_reason {
381 /* Reasons to lower cwnd. */
382 enum sctp_lower_cwnd {
383 SCTP_LOWER_CWND_T3_RTX,
384 SCTP_LOWER_CWND_FAST_RTX,
385 SCTP_LOWER_CWND_ECNE,
386 SCTP_LOWER_CWND_INACTIVE,
390 /* SCTP-AUTH Necessary constants */
392 /* SCTP-AUTH, Section 3.3
394 * The following Table 2 shows the currently defined values for HMAC
397 * +-----------------+--------------------------+
398 * | HMAC Identifier | Message Digest Algorithm |
399 * +-----------------+--------------------------+
401 * | 1 | SHA-1 defined in [8] |
403 * | 3 | SHA-256 defined in [8] |
404 * +-----------------+--------------------------+
407 SCTP_AUTH_HMAC_ID_RESERVED_0,
408 SCTP_AUTH_HMAC_ID_SHA1,
409 SCTP_AUTH_HMAC_ID_RESERVED_2,
410 #if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE)
411 SCTP_AUTH_HMAC_ID_SHA256,
416 #define SCTP_AUTH_HMAC_ID_MAX __SCTP_AUTH_HMAC_MAX - 1
417 #define SCTP_AUTH_NUM_HMACS __SCTP_AUTH_HMAC_MAX
418 #define SCTP_SHA1_SIG_SIZE 20
419 #define SCTP_SHA256_SIG_SIZE 32
421 /* SCTP-AUTH, Section 3.2
422 * The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks
423 * MUST NOT be listed in the CHUNKS parameter
425 #define SCTP_NUM_NOAUTH_CHUNKS 4
426 #define SCTP_AUTH_MAX_CHUNKS (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS)
428 /* SCTP-AUTH Section 6.1
429 * The RANDOM parameter MUST contain a 32 byte random number.
431 #define SCTP_AUTH_RANDOM_LENGTH 32
433 #endif /* __sctp_constants_h__ */