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_type { 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 /* Internal error codes */ 152 enum sctp_ierror { 153 SCTP_IERROR_NO_ERROR = 0, 154 SCTP_IERROR_BASE = 1000, 155 SCTP_IERROR_NO_COOKIE, 156 SCTP_IERROR_BAD_SIG, 157 SCTP_IERROR_STALE_COOKIE, 158 SCTP_IERROR_NOMEM, 159 SCTP_IERROR_MALFORMED, 160 SCTP_IERROR_BAD_TAG, 161 SCTP_IERROR_BIG_GAP, 162 SCTP_IERROR_DUP_TSN, 163 SCTP_IERROR_HIGH_TSN, 164 SCTP_IERROR_IGNORE_TSN, 165 SCTP_IERROR_NO_DATA, 166 SCTP_IERROR_BAD_STREAM, 167 SCTP_IERROR_BAD_PORTS, 168 SCTP_IERROR_AUTH_BAD_HMAC, 169 SCTP_IERROR_AUTH_BAD_KEYID, 170 SCTP_IERROR_PROTO_VIOLATION, 171 SCTP_IERROR_ERROR, 172 SCTP_IERROR_ABORT, 173 }; 174 175 176 177 /* SCTP state defines for internal state machine */ 178 enum sctp_state { 179 180 SCTP_STATE_CLOSED = 0, 181 SCTP_STATE_COOKIE_WAIT = 1, 182 SCTP_STATE_COOKIE_ECHOED = 2, 183 SCTP_STATE_ESTABLISHED = 3, 184 SCTP_STATE_SHUTDOWN_PENDING = 4, 185 SCTP_STATE_SHUTDOWN_SENT = 5, 186 SCTP_STATE_SHUTDOWN_RECEIVED = 6, 187 SCTP_STATE_SHUTDOWN_ACK_SENT = 7, 188 189 }; 190 191 #define SCTP_STATE_MAX SCTP_STATE_SHUTDOWN_ACK_SENT 192 #define SCTP_STATE_NUM_STATES (SCTP_STATE_MAX + 1) 193 194 /* These are values for sk->state. 195 * For a UDP-style SCTP socket, the states are defined as follows 196 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to 197 * accept new associations, but it can initiate the creation of new ones. 198 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to 199 * accept new associations and can initiate the creation of new ones. 200 * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off 201 * socket with one association. 202 * For a TCP-style SCTP socket, the states are defined as follows 203 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to 204 * accept new associations, but it can initiate the creation of new ones. 205 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to 206 * accept new associations, but cannot initiate the creation of new ones. 207 * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single 208 * association. 209 */ 210 enum sctp_sock_state { 211 SCTP_SS_CLOSED = TCP_CLOSE, 212 SCTP_SS_LISTENING = TCP_LISTEN, 213 SCTP_SS_ESTABLISHING = TCP_SYN_SENT, 214 SCTP_SS_ESTABLISHED = TCP_ESTABLISHED, 215 SCTP_SS_CLOSING = TCP_CLOSE_WAIT, 216 }; 217 218 /* These functions map various type to printable names. */ 219 const char *sctp_cname(const union sctp_subtype id); /* chunk types */ 220 const char *sctp_oname(const union sctp_subtype id); /* other events */ 221 const char *sctp_tname(const union sctp_subtype id); /* timeouts */ 222 const char *sctp_pname(const union sctp_subtype id); /* primitives */ 223 224 /* This is a table of printable names of sctp_state_t's. */ 225 extern const char *const sctp_state_tbl[]; 226 extern const char *const sctp_evttype_tbl[]; 227 extern const char *const sctp_status_tbl[]; 228 229 /* Maximum chunk length considering padding requirements. */ 230 enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) }; 231 232 /* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little 233 * harder (until reaching ESTABLISHED state). 234 */ 235 enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 }; 236 237 /* Guess at how big to make the TSN mapping array. 238 * We guarantee that we can handle at least this big a gap between the 239 * cumulative ACK and the highest TSN. In practice, we can often 240 * handle up to twice this value. 241 * 242 * NEVER make this more than 32767 (2^15-1). The Gap Ack Blocks in a 243 * SACK (see section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE 244 * must be less than 65535 (2^16 - 1), or we will have overflow 245 * problems creating SACK's. 246 */ 247 #define SCTP_TSN_MAP_INITIAL BITS_PER_LONG 248 #define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL 249 #define SCTP_TSN_MAP_SIZE 4096 250 251 /* We will not record more than this many duplicate TSNs between two 252 * SACKs. The minimum PMTU is 512. Remove all the headers and there 253 * is enough room for 117 duplicate reports. Round down to the 254 * nearest power of 2. 255 */ 256 enum { SCTP_MAX_DUP_TSNS = 16 }; 257 enum { SCTP_MAX_GABS = 16 }; 258 259 /* Heartbeat interval - 30 secs */ 260 #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT (30*1000) 261 262 /* Delayed sack timer - 200ms */ 263 #define SCTP_DEFAULT_TIMEOUT_SACK (200) 264 265 /* RTO.Initial - 3 seconds 266 * RTO.Min - 1 second 267 * RTO.Max - 60 seconds 268 * RTO.Alpha - 1/8 269 * RTO.Beta - 1/4 270 */ 271 #define SCTP_RTO_INITIAL (3 * 1000) 272 #define SCTP_RTO_MIN (1 * 1000) 273 #define SCTP_RTO_MAX (60 * 1000) 274 275 #define SCTP_RTO_ALPHA 3 /* 1/8 when converted to right shifts. */ 276 #define SCTP_RTO_BETA 2 /* 1/4 when converted to right shifts. */ 277 278 /* Maximum number of new data packets that can be sent in a burst. */ 279 #define SCTP_DEFAULT_MAX_BURST 4 280 281 #define SCTP_CLOCK_GRANULARITY 1 /* 1 jiffy */ 282 283 #define SCTP_DEFAULT_COOKIE_LIFE (60 * 1000) /* 60 seconds */ 284 285 #define SCTP_DEFAULT_MINWINDOW 1500 /* default minimum rwnd size */ 286 #define SCTP_DEFAULT_MAXWINDOW 65535 /* default rwnd size */ 287 #define SCTP_DEFAULT_RWND_SHIFT 4 /* by default, update on 1/16 of 288 * rcvbuf, which is 1/8 of initial 289 * window 290 */ 291 #define SCTP_DEFAULT_MAXSEGMENT 1500 /* MTU size, this is the limit 292 * to which we will raise the P-MTU. 293 */ 294 #define SCTP_DEFAULT_MINSEGMENT 512 /* MTU size ... if no mtu disc */ 295 296 #define SCTP_SECRET_SIZE 32 /* Number of octets in a 256 bits. */ 297 298 #define SCTP_SIGNATURE_SIZE 20 /* size of a SLA-1 signature */ 299 300 #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash 301 * functions simpler to write. 302 */ 303 304 /* These return values describe the success or failure of a number of 305 * routines which form the lower interface to SCTP_outqueue. 306 */ 307 enum sctp_xmit { 308 SCTP_XMIT_OK, 309 SCTP_XMIT_PMTU_FULL, 310 SCTP_XMIT_RWND_FULL, 311 SCTP_XMIT_DELAY, 312 }; 313 314 /* These are the commands for manipulating transports. */ 315 enum sctp_transport_cmd { 316 SCTP_TRANSPORT_UP, 317 SCTP_TRANSPORT_DOWN, 318 SCTP_TRANSPORT_PF, 319 }; 320 321 /* These are the address scopes defined mainly for IPv4 addresses 322 * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>. 323 * These scopes are hopefully generic enough to be used on scoping both 324 * IPv4 and IPv6 addresses in SCTP. 325 * At this point, the IPv6 scopes will be mapped to these internal scopes 326 * as much as possible. 327 */ 328 enum sctp_scope { 329 SCTP_SCOPE_GLOBAL, /* IPv4 global addresses */ 330 SCTP_SCOPE_PRIVATE, /* IPv4 private addresses */ 331 SCTP_SCOPE_LINK, /* IPv4 link local address */ 332 SCTP_SCOPE_LOOPBACK, /* IPv4 loopback address */ 333 SCTP_SCOPE_UNUSABLE, /* IPv4 unusable addresses */ 334 }; 335 336 enum { 337 SCTP_SCOPE_POLICY_DISABLE, /* Disable IPv4 address scoping */ 338 SCTP_SCOPE_POLICY_ENABLE, /* Enable IPv4 address scoping */ 339 SCTP_SCOPE_POLICY_PRIVATE, /* Follow draft but allow IPv4 private addresses */ 340 SCTP_SCOPE_POLICY_LINK, /* Follow draft but allow IPv4 link local addresses */ 341 }; 342 343 #define SCTP_SCOPE_POLICY_MAX SCTP_SCOPE_POLICY_LINK 344 345 /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>, 346 * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24, 347 * 192.88.99.0/24. 348 * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP 349 * addresses. 350 */ 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_test_198(a) || \ 356 ipv4_is_anycast_6to4(a)) 357 358 /* Flags used for the bind address copy functions. */ 359 #define SCTP_ADDR6_ALLOWED 0x00000001 /* IPv6 address is allowed by 360 local sock family */ 361 #define SCTP_ADDR4_PEERSUPP 0x00000002 /* IPv4 address is supported by 362 peer */ 363 #define SCTP_ADDR6_PEERSUPP 0x00000004 /* IPv6 address is supported by 364 peer */ 365 366 /* Reasons to retransmit. */ 367 enum sctp_retransmit_reason { 368 SCTP_RTXR_T3_RTX, 369 SCTP_RTXR_FAST_RTX, 370 SCTP_RTXR_PMTUD, 371 SCTP_RTXR_T1_RTX, 372 }; 373 374 /* Reasons to lower cwnd. */ 375 enum sctp_lower_cwnd { 376 SCTP_LOWER_CWND_T3_RTX, 377 SCTP_LOWER_CWND_FAST_RTX, 378 SCTP_LOWER_CWND_ECNE, 379 SCTP_LOWER_CWND_INACTIVE, 380 }; 381 382 383 /* SCTP-AUTH Necessary constants */ 384 385 /* SCTP-AUTH, Section 3.3 386 * 387 * The following Table 2 shows the currently defined values for HMAC 388 * identifiers. 389 * 390 * +-----------------+--------------------------+ 391 * | HMAC Identifier | Message Digest Algorithm | 392 * +-----------------+--------------------------+ 393 * | 0 | Reserved | 394 * | 1 | SHA-1 defined in [8] | 395 * | 2 | Reserved | 396 * | 3 | SHA-256 defined in [8] | 397 * +-----------------+--------------------------+ 398 */ 399 enum { 400 SCTP_AUTH_HMAC_ID_RESERVED_0, 401 SCTP_AUTH_HMAC_ID_SHA1, 402 SCTP_AUTH_HMAC_ID_RESERVED_2, 403 #if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE) 404 SCTP_AUTH_HMAC_ID_SHA256, 405 #endif 406 __SCTP_AUTH_HMAC_MAX 407 }; 408 409 #define SCTP_AUTH_HMAC_ID_MAX __SCTP_AUTH_HMAC_MAX - 1 410 #define SCTP_AUTH_NUM_HMACS __SCTP_AUTH_HMAC_MAX 411 #define SCTP_SHA1_SIG_SIZE 20 412 #define SCTP_SHA256_SIG_SIZE 32 413 414 /* SCTP-AUTH, Section 3.2 415 * The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks 416 * MUST NOT be listed in the CHUNKS parameter 417 */ 418 #define SCTP_NUM_NOAUTH_CHUNKS 4 419 #define SCTP_AUTH_MAX_CHUNKS (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS) 420 421 /* SCTP-AUTH Section 6.1 422 * The RANDOM parameter MUST contain a 32 byte random number. 423 */ 424 #define SCTP_AUTH_RANDOM_LENGTH 32 425 426 #endif /* __sctp_constants_h__ */ 427