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 sctp_sock_state_t */
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_AUTH_CHUNK_TYPES 1
65 #define SCTP_NUM_CHUNK_TYPES (SCTP_NUM_BASE_CHUNK_TYPES + \
66 SCTP_NUM_ADDIP_CHUNK_TYPES +\
67 SCTP_NUM_PRSCTP_CHUNK_TYPES +\
68 SCTP_NUM_AUTH_CHUNK_TYPES)
70 /* These are the different flavours of event. */
73 SCTP_EVENT_T_CHUNK = 1,
76 SCTP_EVENT_T_PRIMITIVE
80 /* As a convenience for the state machine, we append SCTP_EVENT_* and
81 * SCTP_ULP_* to the list of possible chunks.
85 SCTP_EVENT_TIMEOUT_NONE = 0,
86 SCTP_EVENT_TIMEOUT_T1_COOKIE,
87 SCTP_EVENT_TIMEOUT_T1_INIT,
88 SCTP_EVENT_TIMEOUT_T2_SHUTDOWN,
89 SCTP_EVENT_TIMEOUT_T3_RTX,
90 SCTP_EVENT_TIMEOUT_T4_RTO,
91 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD,
92 SCTP_EVENT_TIMEOUT_HEARTBEAT,
93 SCTP_EVENT_TIMEOUT_SACK,
94 SCTP_EVENT_TIMEOUT_AUTOCLOSE,
95 } sctp_event_timeout_t;
97 #define SCTP_EVENT_TIMEOUT_MAX SCTP_EVENT_TIMEOUT_AUTOCLOSE
98 #define SCTP_NUM_TIMEOUT_TYPES (SCTP_EVENT_TIMEOUT_MAX + 1)
101 SCTP_EVENT_NO_PENDING_TSN = 0,
102 SCTP_EVENT_ICMP_PROTO_UNREACH,
103 } sctp_event_other_t;
105 #define SCTP_EVENT_OTHER_MAX SCTP_EVENT_ICMP_PROTO_UNREACH
106 #define SCTP_NUM_OTHER_TYPES (SCTP_EVENT_OTHER_MAX + 1)
108 /* These are primitive requests from the ULP. */
110 SCTP_PRIMITIVE_ASSOCIATE = 0,
111 SCTP_PRIMITIVE_SHUTDOWN,
112 SCTP_PRIMITIVE_ABORT,
114 SCTP_PRIMITIVE_REQUESTHEARTBEAT,
115 SCTP_PRIMITIVE_ASCONF,
116 } sctp_event_primitive_t;
118 #define SCTP_EVENT_PRIMITIVE_MAX SCTP_PRIMITIVE_ASCONF
119 #define SCTP_NUM_PRIMITIVE_TYPES (SCTP_EVENT_PRIMITIVE_MAX + 1)
121 /* We define here a utility type for manipulating subtypes.
122 * The subtype constructors all work like this:
124 * sctp_subtype_t foo = SCTP_ST_CHUNK(SCTP_CID_INIT);
129 sctp_event_timeout_t timeout;
130 sctp_event_other_t other;
131 sctp_event_primitive_t primitive;
134 #define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \
135 static inline sctp_subtype_t \
136 SCTP_ST_## _name (_type _arg) \
137 { sctp_subtype_t _retval; _retval._elt = _arg; return _retval; }
139 SCTP_SUBTYPE_CONSTRUCTOR(CHUNK, sctp_cid_t, chunk)
140 SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT, sctp_event_timeout_t, timeout)
141 SCTP_SUBTYPE_CONSTRUCTOR(OTHER, sctp_event_other_t, other)
142 SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE, sctp_event_primitive_t, primitive)
145 #define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA)
147 /* Calculate the actual data size in a data chunk */
148 #define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end)\
149 - (unsigned long)(c->chunk_hdr)\
150 - sizeof(sctp_data_chunk_t)))
152 /* Internal error codes */
155 SCTP_IERROR_NO_ERROR = 0,
156 SCTP_IERROR_BASE = 1000,
157 SCTP_IERROR_NO_COOKIE,
159 SCTP_IERROR_STALE_COOKIE,
161 SCTP_IERROR_MALFORMED,
165 SCTP_IERROR_HIGH_TSN,
166 SCTP_IERROR_IGNORE_TSN,
168 SCTP_IERROR_BAD_STREAM,
169 SCTP_IERROR_BAD_PORTS,
170 SCTP_IERROR_AUTH_BAD_HMAC,
171 SCTP_IERROR_AUTH_BAD_KEYID,
172 SCTP_IERROR_PROTO_VIOLATION,
179 /* SCTP state defines for internal state machine */
182 SCTP_STATE_CLOSED = 0,
183 SCTP_STATE_COOKIE_WAIT = 1,
184 SCTP_STATE_COOKIE_ECHOED = 2,
185 SCTP_STATE_ESTABLISHED = 3,
186 SCTP_STATE_SHUTDOWN_PENDING = 4,
187 SCTP_STATE_SHUTDOWN_SENT = 5,
188 SCTP_STATE_SHUTDOWN_RECEIVED = 6,
189 SCTP_STATE_SHUTDOWN_ACK_SENT = 7,
193 #define SCTP_STATE_MAX SCTP_STATE_SHUTDOWN_ACK_SENT
194 #define SCTP_STATE_NUM_STATES (SCTP_STATE_MAX + 1)
196 /* These are values for sk->state.
197 * For a UDP-style SCTP socket, the states are defined as follows
198 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
199 * accept new associations, but it can initiate the creation of new ones.
200 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
201 * accept new associations and can initiate the creation of new ones.
202 * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off
203 * socket with one association.
204 * For a TCP-style SCTP socket, the states are defined as follows
205 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
206 * accept new associations, but it can initiate the creation of new ones.
207 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
208 * accept new associations, but cannot initiate the creation of new ones.
209 * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single
213 SCTP_SS_CLOSED = TCP_CLOSE,
214 SCTP_SS_LISTENING = TCP_LISTEN,
215 SCTP_SS_ESTABLISHING = TCP_SYN_SENT,
216 SCTP_SS_ESTABLISHED = TCP_ESTABLISHED,
217 SCTP_SS_CLOSING = TCP_CLOSING,
220 /* These functions map various type to printable names. */
221 const char *sctp_cname(const sctp_subtype_t); /* chunk types */
222 const char *sctp_oname(const sctp_subtype_t); /* other events */
223 const char *sctp_tname(const sctp_subtype_t); /* timeouts */
224 const char *sctp_pname(const sctp_subtype_t); /* primitives */
226 /* This is a table of printable names of sctp_state_t's. */
227 extern const char *const sctp_state_tbl[];
228 extern const char *const sctp_evttype_tbl[];
229 extern const char *const sctp_status_tbl[];
231 /* Maximum chunk length considering padding requirements. */
232 enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) };
234 /* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little
235 * harder (until reaching ESTABLISHED state).
237 enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 };
239 /* Guess at how big to make the TSN mapping array.
240 * We guarantee that we can handle at least this big a gap between the
241 * cumulative ACK and the highest TSN. In practice, we can often
242 * handle up to twice this value.
244 * NEVER make this more than 32767 (2^15-1). The Gap Ack Blocks in a
245 * SACK (see section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE
246 * must be less than 65535 (2^16 - 1), or we will have overflow
247 * problems creating SACK's.
249 #define SCTP_TSN_MAP_INITIAL BITS_PER_LONG
250 #define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL
251 #define SCTP_TSN_MAP_SIZE 4096
253 /* We will not record more than this many duplicate TSNs between two
254 * SACKs. The minimum PMTU is 576. Remove all the headers and there
255 * is enough room for 131 duplicate reports. Round down to the
256 * nearest power of 2.
258 enum { SCTP_MIN_PMTU = 576 };
259 enum { SCTP_MAX_DUP_TSNS = 16 };
260 enum { SCTP_MAX_GABS = 16 };
262 /* Heartbeat interval - 30 secs */
263 #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT (30*1000)
265 /* Delayed sack timer - 200ms */
266 #define SCTP_DEFAULT_TIMEOUT_SACK (200)
268 /* RTO.Initial - 3 seconds
270 * RTO.Max - 60 seconds
274 #define SCTP_RTO_INITIAL (3 * 1000)
275 #define SCTP_RTO_MIN (1 * 1000)
276 #define SCTP_RTO_MAX (60 * 1000)
278 #define SCTP_RTO_ALPHA 3 /* 1/8 when converted to right shifts. */
279 #define SCTP_RTO_BETA 2 /* 1/4 when converted to right shifts. */
281 /* Maximum number of new data packets that can be sent in a burst. */
282 #define SCTP_DEFAULT_MAX_BURST 4
284 #define SCTP_CLOCK_GRANULARITY 1 /* 1 jiffy */
286 #define SCTP_DEFAULT_COOKIE_LIFE (60 * 1000) /* 60 seconds */
288 #define SCTP_DEFAULT_MINWINDOW 1500 /* default minimum rwnd size */
289 #define SCTP_DEFAULT_MAXWINDOW 65535 /* default rwnd size */
290 #define SCTP_DEFAULT_RWND_SHIFT 4 /* by default, update on 1/16 of
291 * rcvbuf, which is 1/8 of initial
294 #define SCTP_DEFAULT_MAXSEGMENT 1500 /* MTU size, this is the limit
295 * to which we will raise the P-MTU.
297 #define SCTP_DEFAULT_MINSEGMENT 512 /* MTU size ... if no mtu disc */
299 #define SCTP_SECRET_SIZE 32 /* Number of octets in a 256 bits. */
301 #define SCTP_SIGNATURE_SIZE 20 /* size of a SLA-1 signature */
303 #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash
304 * functions simpler to write.
307 /* These return values describe the success or failure of a number of
308 * routines which form the lower interface to SCTP_outqueue.
317 /* These are the commands for manipulating transports. */
322 } sctp_transport_cmd_t;
324 /* These are the address scopes defined mainly for IPv4 addresses
325 * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
326 * These scopes are hopefully generic enough to be used on scoping both
327 * IPv4 and IPv6 addresses in SCTP.
328 * At this point, the IPv6 scopes will be mapped to these internal scopes
329 * as much as possible.
332 SCTP_SCOPE_GLOBAL, /* IPv4 global addresses */
333 SCTP_SCOPE_PRIVATE, /* IPv4 private addresses */
334 SCTP_SCOPE_LINK, /* IPv4 link local address */
335 SCTP_SCOPE_LOOPBACK, /* IPv4 loopback address */
336 SCTP_SCOPE_UNUSABLE, /* IPv4 unusable addresses */
340 SCTP_SCOPE_POLICY_DISABLE, /* Disable IPv4 address scoping */
341 SCTP_SCOPE_POLICY_ENABLE, /* Enable IPv4 address scoping */
342 SCTP_SCOPE_POLICY_PRIVATE, /* Follow draft but allow IPv4 private addresses */
343 SCTP_SCOPE_POLICY_LINK, /* Follow draft but allow IPv4 link local addresses */
344 } sctp_scope_policy_t;
346 /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>,
347 * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 192.88.99.0/24.
348 * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP
351 #define IS_IPV4_UNUSABLE_ADDRESS(a) \
352 ((htonl(INADDR_BROADCAST) == a) || \
353 ipv4_is_multicast(a) || \
354 ipv4_is_zeronet(a) || \
355 ipv4_is_anycast_6to4(a))
357 /* Flags used for the bind address copy functions. */
358 #define SCTP_ADDR4_ALLOWED 0x00000001 /* IPv4 address is allowed by
360 #define SCTP_ADDR6_ALLOWED 0x00000002 /* IPv6 address is allowed by
362 #define SCTP_ADDR4_PEERSUPP 0x00000004 /* IPv4 address is supported by
364 #define SCTP_ADDR6_PEERSUPP 0x00000008 /* IPv6 address is supported by
367 /* Reasons to retransmit. */
373 } sctp_retransmit_reason_t;
375 /* Reasons to lower cwnd. */
377 SCTP_LOWER_CWND_T3_RTX,
378 SCTP_LOWER_CWND_FAST_RTX,
379 SCTP_LOWER_CWND_ECNE,
380 SCTP_LOWER_CWND_INACTIVE,
384 /* SCTP-AUTH Necessary constants */
386 /* SCTP-AUTH, Section 3.3
388 * The following Table 2 shows the currently defined values for HMAC
391 * +-----------------+--------------------------+
392 * | HMAC Identifier | Message Digest Algorithm |
393 * +-----------------+--------------------------+
395 * | 1 | SHA-1 defined in [8] |
397 * | 3 | SHA-256 defined in [8] |
398 * +-----------------+--------------------------+
401 SCTP_AUTH_HMAC_ID_RESERVED_0,
402 SCTP_AUTH_HMAC_ID_SHA1,
403 SCTP_AUTH_HMAC_ID_RESERVED_2,
404 #if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE)
405 SCTP_AUTH_HMAC_ID_SHA256,
410 #define SCTP_AUTH_HMAC_ID_MAX __SCTP_AUTH_HMAC_MAX - 1
411 #define SCTP_AUTH_NUM_HMACS __SCTP_AUTH_HMAC_MAX
412 #define SCTP_SHA1_SIG_SIZE 20
413 #define SCTP_SHA256_SIG_SIZE 32
415 /* SCTP-AUTH, Section 3.2
416 * The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks
417 * MUST NOT be listed in the CHUNKS parameter
419 #define SCTP_NUM_NOAUTH_CHUNKS 4
420 #define SCTP_AUTH_MAX_CHUNKS (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS)
422 /* SCTP-AUTH Section 6.1
423 * The RANDOM parameter MUST contain a 32 byte random number.
425 #define SCTP_AUTH_RANDOM_LENGTH 32
427 #endif /* __sctp_constants_h__ */