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. 6 * 7 * This file is part of the SCTP kernel implementation 8 * 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) 13 * any later version. 14 * 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. 20 * 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/>. 24 * 25 * Please send any bug reports or fixes you make to the 26 * email address(es): 27 * lksctp developers <linux-sctp@vger.kernel.org> 28 * 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> 38 */ 39 40 #ifndef __sctp_constants_h__ 41 #define __sctp_constants_h__ 42 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 */ 46 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 }; 51 52 /* Since CIDs are sparse, we need all four of the following 53 * symbols. CIDs are dense through SCTP_CID_BASE_MAX. 54 */ 55 #define SCTP_CID_BASE_MAX SCTP_CID_SHUTDOWN_COMPLETE 56 57 #define SCTP_NUM_BASE_CHUNK_TYPES (SCTP_CID_BASE_MAX + 1) 58 59 #define SCTP_NUM_ADDIP_CHUNK_TYPES 2 60 61 #define SCTP_NUM_PRSCTP_CHUNK_TYPES 1 62 63 #define SCTP_NUM_RECONF_CHUNK_TYPES 1 64 65 #define SCTP_NUM_AUTH_CHUNK_TYPES 1 66 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) 72 73 /* These are the different flavours of event. */ 74 enum sctp_event { 75 SCTP_EVENT_T_CHUNK = 1, 76 SCTP_EVENT_T_TIMEOUT, 77 SCTP_EVENT_T_OTHER, 78 SCTP_EVENT_T_PRIMITIVE 79 }; 80 81 /* As a convenience for the state machine, we append SCTP_EVENT_* and 82 * SCTP_ULP_* to the list of possible chunks. 83 */ 84 85 enum sctp_event_timeout { 86 SCTP_EVENT_TIMEOUT_NONE = 0, 87 SCTP_EVENT_TIMEOUT_T1_COOKIE, 88 SCTP_EVENT_TIMEOUT_T1_INIT, 89 SCTP_EVENT_TIMEOUT_T2_SHUTDOWN, 90 SCTP_EVENT_TIMEOUT_T3_RTX, 91 SCTP_EVENT_TIMEOUT_T4_RTO, 92 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD, 93 SCTP_EVENT_TIMEOUT_HEARTBEAT, 94 SCTP_EVENT_TIMEOUT_RECONF, 95 SCTP_EVENT_TIMEOUT_SACK, 96 SCTP_EVENT_TIMEOUT_AUTOCLOSE, 97 }; 98 99 #define SCTP_EVENT_TIMEOUT_MAX SCTP_EVENT_TIMEOUT_AUTOCLOSE 100 #define SCTP_NUM_TIMEOUT_TYPES (SCTP_EVENT_TIMEOUT_MAX + 1) 101 102 enum sctp_event_other { 103 SCTP_EVENT_NO_PENDING_TSN = 0, 104 SCTP_EVENT_ICMP_PROTO_UNREACH, 105 }; 106 107 #define SCTP_EVENT_OTHER_MAX SCTP_EVENT_ICMP_PROTO_UNREACH 108 #define SCTP_NUM_OTHER_TYPES (SCTP_EVENT_OTHER_MAX + 1) 109 110 /* These are primitive requests from the ULP. */ 111 enum sctp_event_primitive { 112 SCTP_PRIMITIVE_ASSOCIATE = 0, 113 SCTP_PRIMITIVE_SHUTDOWN, 114 SCTP_PRIMITIVE_ABORT, 115 SCTP_PRIMITIVE_SEND, 116 SCTP_PRIMITIVE_REQUESTHEARTBEAT, 117 SCTP_PRIMITIVE_ASCONF, 118 SCTP_PRIMITIVE_RECONF, 119 }; 120 121 #define SCTP_EVENT_PRIMITIVE_MAX SCTP_PRIMITIVE_RECONF 122 #define SCTP_NUM_PRIMITIVE_TYPES (SCTP_EVENT_PRIMITIVE_MAX + 1) 123 124 /* We define here a utility type for manipulating subtypes. 125 * The subtype constructors all work like this: 126 * 127 * union sctp_subtype foo = SCTP_ST_CHUNK(SCTP_CID_INIT); 128 */ 129 130 union sctp_subtype { 131 enum sctp_cid chunk; 132 enum sctp_event_timeout timeout; 133 enum sctp_event_other other; 134 enum sctp_event_primitive primitive; 135 }; 136 137 #define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \ 138 static inline union sctp_subtype \ 139 SCTP_ST_## _name (_type _arg) \ 140 { union sctp_subtype _retval; _retval._elt = _arg; return _retval; } 141 142 SCTP_SUBTYPE_CONSTRUCTOR(CHUNK, enum sctp_cid, chunk) 143 SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT, enum sctp_event_timeout, timeout) 144 SCTP_SUBTYPE_CONSTRUCTOR(OTHER, enum sctp_event_other, other) 145 SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE, enum sctp_event_primitive, primitive) 146 147 148 #define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA || \ 149 a->chunk_hdr->type == SCTP_CID_I_DATA) 150 151 /* Calculate the actual data size in a data chunk */ 152 #define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end) - \ 153 (unsigned long)(c->chunk_hdr) - \ 154 sctp_datachk_len(&c->asoc->stream))) 155 156 /* Internal error codes */ 157 enum sctp_ierror { 158 SCTP_IERROR_NO_ERROR = 0, 159 SCTP_IERROR_BASE = 1000, 160 SCTP_IERROR_NO_COOKIE, 161 SCTP_IERROR_BAD_SIG, 162 SCTP_IERROR_STALE_COOKIE, 163 SCTP_IERROR_NOMEM, 164 SCTP_IERROR_MALFORMED, 165 SCTP_IERROR_BAD_TAG, 166 SCTP_IERROR_BIG_GAP, 167 SCTP_IERROR_DUP_TSN, 168 SCTP_IERROR_HIGH_TSN, 169 SCTP_IERROR_IGNORE_TSN, 170 SCTP_IERROR_NO_DATA, 171 SCTP_IERROR_BAD_STREAM, 172 SCTP_IERROR_BAD_PORTS, 173 SCTP_IERROR_AUTH_BAD_HMAC, 174 SCTP_IERROR_AUTH_BAD_KEYID, 175 SCTP_IERROR_PROTO_VIOLATION, 176 SCTP_IERROR_ERROR, 177 SCTP_IERROR_ABORT, 178 }; 179 180 181 182 /* SCTP state defines for internal state machine */ 183 enum sctp_state { 184 185 SCTP_STATE_CLOSED = 0, 186 SCTP_STATE_COOKIE_WAIT = 1, 187 SCTP_STATE_COOKIE_ECHOED = 2, 188 SCTP_STATE_ESTABLISHED = 3, 189 SCTP_STATE_SHUTDOWN_PENDING = 4, 190 SCTP_STATE_SHUTDOWN_SENT = 5, 191 SCTP_STATE_SHUTDOWN_RECEIVED = 6, 192 SCTP_STATE_SHUTDOWN_ACK_SENT = 7, 193 194 }; 195 196 #define SCTP_STATE_MAX SCTP_STATE_SHUTDOWN_ACK_SENT 197 #define SCTP_STATE_NUM_STATES (SCTP_STATE_MAX + 1) 198 199 /* These are values for sk->state. 200 * For a UDP-style SCTP socket, the states are defined as follows 201 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to 202 * accept new associations, but it can initiate the creation of new ones. 203 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to 204 * accept new associations and can initiate the creation of new ones. 205 * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off 206 * socket with one association. 207 * For a TCP-style SCTP socket, the states are defined as follows 208 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to 209 * accept new associations, but it can initiate the creation of new ones. 210 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to 211 * accept new associations, but cannot initiate the creation of new ones. 212 * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single 213 * association. 214 */ 215 enum sctp_sock_state { 216 SCTP_SS_CLOSED = TCP_CLOSE, 217 SCTP_SS_LISTENING = TCP_LISTEN, 218 SCTP_SS_ESTABLISHING = TCP_SYN_SENT, 219 SCTP_SS_ESTABLISHED = TCP_ESTABLISHED, 220 SCTP_SS_CLOSING = TCP_CLOSE_WAIT, 221 }; 222 223 /* These functions map various type to printable names. */ 224 const char *sctp_cname(const union sctp_subtype id); /* chunk types */ 225 const char *sctp_oname(const union sctp_subtype id); /* other events */ 226 const char *sctp_tname(const union sctp_subtype id); /* timeouts */ 227 const char *sctp_pname(const union sctp_subtype id); /* primitives */ 228 229 /* This is a table of printable names of sctp_state_t's. */ 230 extern const char *const sctp_state_tbl[]; 231 extern const char *const sctp_evttype_tbl[]; 232 extern const char *const sctp_status_tbl[]; 233 234 /* Maximum chunk length considering padding requirements. */ 235 enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) }; 236 237 /* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little 238 * harder (until reaching ESTABLISHED state). 239 */ 240 enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 }; 241 242 /* Guess at how big to make the TSN mapping array. 243 * We guarantee that we can handle at least this big a gap between the 244 * cumulative ACK and the highest TSN. In practice, we can often 245 * handle up to twice this value. 246 * 247 * NEVER make this more than 32767 (2^15-1). The Gap Ack Blocks in a 248 * SACK (see section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE 249 * must be less than 65535 (2^16 - 1), or we will have overflow 250 * problems creating SACK's. 251 */ 252 #define SCTP_TSN_MAP_INITIAL BITS_PER_LONG 253 #define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL 254 #define SCTP_TSN_MAP_SIZE 4096 255 256 /* We will not record more than this many duplicate TSNs between two 257 * SACKs. The minimum PMTU is 512. Remove all the headers and there 258 * is enough room for 117 duplicate reports. Round down to the 259 * nearest power of 2. 260 */ 261 enum { SCTP_MAX_DUP_TSNS = 16 }; 262 enum { SCTP_MAX_GABS = 16 }; 263 264 /* Heartbeat interval - 30 secs */ 265 #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT (30*1000) 266 267 /* Delayed sack timer - 200ms */ 268 #define SCTP_DEFAULT_TIMEOUT_SACK (200) 269 270 /* RTO.Initial - 3 seconds 271 * RTO.Min - 1 second 272 * RTO.Max - 60 seconds 273 * RTO.Alpha - 1/8 274 * RTO.Beta - 1/4 275 */ 276 #define SCTP_RTO_INITIAL (3 * 1000) 277 #define SCTP_RTO_MIN (1 * 1000) 278 #define SCTP_RTO_MAX (60 * 1000) 279 280 #define SCTP_RTO_ALPHA 3 /* 1/8 when converted to right shifts. */ 281 #define SCTP_RTO_BETA 2 /* 1/4 when converted to right shifts. */ 282 283 /* Maximum number of new data packets that can be sent in a burst. */ 284 #define SCTP_DEFAULT_MAX_BURST 4 285 286 #define SCTP_CLOCK_GRANULARITY 1 /* 1 jiffy */ 287 288 #define SCTP_DEFAULT_COOKIE_LIFE (60 * 1000) /* 60 seconds */ 289 290 #define SCTP_DEFAULT_MINWINDOW 1500 /* default minimum rwnd size */ 291 #define SCTP_DEFAULT_MAXWINDOW 65535 /* default rwnd size */ 292 #define SCTP_DEFAULT_RWND_SHIFT 4 /* by default, update on 1/16 of 293 * rcvbuf, which is 1/8 of initial 294 * window 295 */ 296 #define SCTP_DEFAULT_MAXSEGMENT 1500 /* MTU size, this is the limit 297 * to which we will raise the P-MTU. 298 */ 299 #define SCTP_DEFAULT_MINSEGMENT 512 /* MTU size ... if no mtu disc */ 300 301 #define SCTP_SECRET_SIZE 32 /* Number of octets in a 256 bits. */ 302 303 #define SCTP_SIGNATURE_SIZE 20 /* size of a SLA-1 signature */ 304 305 #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash 306 * functions simpler to write. 307 */ 308 309 /* These return values describe the success or failure of a number of 310 * routines which form the lower interface to SCTP_outqueue. 311 */ 312 enum sctp_xmit { 313 SCTP_XMIT_OK, 314 SCTP_XMIT_PMTU_FULL, 315 SCTP_XMIT_RWND_FULL, 316 SCTP_XMIT_DELAY, 317 }; 318 319 /* These are the commands for manipulating transports. */ 320 enum sctp_transport_cmd { 321 SCTP_TRANSPORT_UP, 322 SCTP_TRANSPORT_DOWN, 323 SCTP_TRANSPORT_PF, 324 }; 325 326 /* These are the address scopes defined mainly for IPv4 addresses 327 * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>. 328 * These scopes are hopefully generic enough to be used on scoping both 329 * IPv4 and IPv6 addresses in SCTP. 330 * At this point, the IPv6 scopes will be mapped to these internal scopes 331 * as much as possible. 332 */ 333 enum sctp_scope { 334 SCTP_SCOPE_GLOBAL, /* IPv4 global addresses */ 335 SCTP_SCOPE_PRIVATE, /* IPv4 private addresses */ 336 SCTP_SCOPE_LINK, /* IPv4 link local address */ 337 SCTP_SCOPE_LOOPBACK, /* IPv4 loopback address */ 338 SCTP_SCOPE_UNUSABLE, /* IPv4 unusable addresses */ 339 }; 340 341 enum { 342 SCTP_SCOPE_POLICY_DISABLE, /* Disable IPv4 address scoping */ 343 SCTP_SCOPE_POLICY_ENABLE, /* Enable IPv4 address scoping */ 344 SCTP_SCOPE_POLICY_PRIVATE, /* Follow draft but allow IPv4 private addresses */ 345 SCTP_SCOPE_POLICY_LINK, /* Follow draft but allow IPv4 link local addresses */ 346 }; 347 348 #define SCTP_SCOPE_POLICY_MAX SCTP_SCOPE_POLICY_LINK 349 350 /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>, 351 * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24, 352 * 192.88.99.0/24. 353 * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP 354 * addresses. 355 */ 356 #define IS_IPV4_UNUSABLE_ADDRESS(a) \ 357 ((htonl(INADDR_BROADCAST) == a) || \ 358 ipv4_is_multicast(a) || \ 359 ipv4_is_zeronet(a) || \ 360 ipv4_is_test_198(a) || \ 361 ipv4_is_anycast_6to4(a)) 362 363 /* Flags used for the bind address copy functions. */ 364 #define SCTP_ADDR6_ALLOWED 0x00000001 /* IPv6 address is allowed by 365 local sock family */ 366 #define SCTP_ADDR4_PEERSUPP 0x00000002 /* IPv4 address is supported by 367 peer */ 368 #define SCTP_ADDR6_PEERSUPP 0x00000004 /* IPv6 address is supported by 369 peer */ 370 371 /* Reasons to retransmit. */ 372 enum sctp_retransmit_reason { 373 SCTP_RTXR_T3_RTX, 374 SCTP_RTXR_FAST_RTX, 375 SCTP_RTXR_PMTUD, 376 SCTP_RTXR_T1_RTX, 377 }; 378 379 /* Reasons to lower cwnd. */ 380 enum sctp_lower_cwnd { 381 SCTP_LOWER_CWND_T3_RTX, 382 SCTP_LOWER_CWND_FAST_RTX, 383 SCTP_LOWER_CWND_ECNE, 384 SCTP_LOWER_CWND_INACTIVE, 385 }; 386 387 388 /* SCTP-AUTH Necessary constants */ 389 390 /* SCTP-AUTH, Section 3.3 391 * 392 * The following Table 2 shows the currently defined values for HMAC 393 * identifiers. 394 * 395 * +-----------------+--------------------------+ 396 * | HMAC Identifier | Message Digest Algorithm | 397 * +-----------------+--------------------------+ 398 * | 0 | Reserved | 399 * | 1 | SHA-1 defined in [8] | 400 * | 2 | Reserved | 401 * | 3 | SHA-256 defined in [8] | 402 * +-----------------+--------------------------+ 403 */ 404 enum { 405 SCTP_AUTH_HMAC_ID_RESERVED_0, 406 SCTP_AUTH_HMAC_ID_SHA1, 407 SCTP_AUTH_HMAC_ID_RESERVED_2, 408 #if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE) 409 SCTP_AUTH_HMAC_ID_SHA256, 410 #endif 411 __SCTP_AUTH_HMAC_MAX 412 }; 413 414 #define SCTP_AUTH_HMAC_ID_MAX __SCTP_AUTH_HMAC_MAX - 1 415 #define SCTP_AUTH_NUM_HMACS __SCTP_AUTH_HMAC_MAX 416 #define SCTP_SHA1_SIG_SIZE 20 417 #define SCTP_SHA256_SIG_SIZE 32 418 419 /* SCTP-AUTH, Section 3.2 420 * The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks 421 * MUST NOT be listed in the CHUNKS parameter 422 */ 423 #define SCTP_NUM_NOAUTH_CHUNKS 4 424 #define SCTP_AUTH_MAX_CHUNKS (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS) 425 426 /* SCTP-AUTH Section 6.1 427 * The RANDOM parameter MUST contain a 32 byte random number. 428 */ 429 #define SCTP_AUTH_RANDOM_LENGTH 32 430 431 #endif /* __sctp_constants_h__ */ 432