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, write to 23 * the Free Software Foundation, 59 Temple Place - Suite 330, 24 * Boston, MA 02111-1307, USA. 25 * 26 * Please send any bug reports or fixes you make to the 27 * email address(es): 28 * lksctp developers <lksctp-developers@lists.sourceforge.net> 29 * 30 * Or submit a bug report through the following website: 31 * http://www.sf.net/projects/lksctp 32 * 33 * Written or modified by: 34 * La Monte H.P. Yarroll <piggy@acm.org> 35 * Karl Knutson <karl@athena.chicago.il.us> 36 * Randall Stewart <randall@stewart.chicago.il.us> 37 * Ken Morneau <kmorneau@cisco.com> 38 * Qiaobing Xie <qxie1@motorola.com> 39 * Xingang Guo <xingang.guo@intel.com> 40 * Sridhar Samudrala <samudrala@us.ibm.com> 41 * Daisy Chang <daisyc@us.ibm.com> 42 * 43 * Any bugs reported given to us we will try to fix... any fixes shared will 44 * be incorporated into the next SCTP release. 45 */ 46 47 #ifndef __sctp_constants_h__ 48 #define __sctp_constants_h__ 49 50 #include <linux/sctp.h> 51 #include <linux/ipv6.h> /* For ipv6hdr. */ 52 #include <net/tcp_states.h> /* For TCP states used in sctp_sock_state_t */ 53 54 /* Value used for stream negotiation. */ 55 enum { SCTP_MAX_STREAM = 0xffff }; 56 enum { SCTP_DEFAULT_OUTSTREAMS = 10 }; 57 enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM }; 58 59 /* Since CIDs are sparse, we need all four of the following 60 * symbols. CIDs are dense through SCTP_CID_BASE_MAX. 61 */ 62 #define SCTP_CID_BASE_MAX SCTP_CID_SHUTDOWN_COMPLETE 63 64 #define SCTP_NUM_BASE_CHUNK_TYPES (SCTP_CID_BASE_MAX + 1) 65 66 #define SCTP_NUM_ADDIP_CHUNK_TYPES 2 67 68 #define SCTP_NUM_PRSCTP_CHUNK_TYPES 1 69 70 #define SCTP_NUM_AUTH_CHUNK_TYPES 1 71 72 #define SCTP_NUM_CHUNK_TYPES (SCTP_NUM_BASE_CHUNK_TYPES + \ 73 SCTP_NUM_ADDIP_CHUNK_TYPES +\ 74 SCTP_NUM_PRSCTP_CHUNK_TYPES +\ 75 SCTP_NUM_AUTH_CHUNK_TYPES) 76 77 /* These are the different flavours of event. */ 78 typedef enum { 79 80 SCTP_EVENT_T_CHUNK = 1, 81 SCTP_EVENT_T_TIMEOUT, 82 SCTP_EVENT_T_OTHER, 83 SCTP_EVENT_T_PRIMITIVE 84 85 } sctp_event_t; 86 87 /* As a convenience for the state machine, we append SCTP_EVENT_* and 88 * SCTP_ULP_* to the list of possible chunks. 89 */ 90 91 typedef enum { 92 SCTP_EVENT_TIMEOUT_NONE = 0, 93 SCTP_EVENT_TIMEOUT_T1_COOKIE, 94 SCTP_EVENT_TIMEOUT_T1_INIT, 95 SCTP_EVENT_TIMEOUT_T2_SHUTDOWN, 96 SCTP_EVENT_TIMEOUT_T3_RTX, 97 SCTP_EVENT_TIMEOUT_T4_RTO, 98 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD, 99 SCTP_EVENT_TIMEOUT_HEARTBEAT, 100 SCTP_EVENT_TIMEOUT_SACK, 101 SCTP_EVENT_TIMEOUT_AUTOCLOSE, 102 } sctp_event_timeout_t; 103 104 #define SCTP_EVENT_TIMEOUT_MAX SCTP_EVENT_TIMEOUT_AUTOCLOSE 105 #define SCTP_NUM_TIMEOUT_TYPES (SCTP_EVENT_TIMEOUT_MAX + 1) 106 107 typedef enum { 108 SCTP_EVENT_NO_PENDING_TSN = 0, 109 SCTP_EVENT_ICMP_PROTO_UNREACH, 110 } sctp_event_other_t; 111 112 #define SCTP_EVENT_OTHER_MAX SCTP_EVENT_ICMP_PROTO_UNREACH 113 #define SCTP_NUM_OTHER_TYPES (SCTP_EVENT_OTHER_MAX + 1) 114 115 /* These are primitive requests from the ULP. */ 116 typedef enum { 117 SCTP_PRIMITIVE_ASSOCIATE = 0, 118 SCTP_PRIMITIVE_SHUTDOWN, 119 SCTP_PRIMITIVE_ABORT, 120 SCTP_PRIMITIVE_SEND, 121 SCTP_PRIMITIVE_REQUESTHEARTBEAT, 122 SCTP_PRIMITIVE_ASCONF, 123 } sctp_event_primitive_t; 124 125 #define SCTP_EVENT_PRIMITIVE_MAX SCTP_PRIMITIVE_ASCONF 126 #define SCTP_NUM_PRIMITIVE_TYPES (SCTP_EVENT_PRIMITIVE_MAX + 1) 127 128 /* We define here a utility type for manipulating subtypes. 129 * The subtype constructors all work like this: 130 * 131 * sctp_subtype_t foo = SCTP_ST_CHUNK(SCTP_CID_INIT); 132 */ 133 134 typedef union { 135 sctp_cid_t chunk; 136 sctp_event_timeout_t timeout; 137 sctp_event_other_t other; 138 sctp_event_primitive_t primitive; 139 } sctp_subtype_t; 140 141 #define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \ 142 static inline sctp_subtype_t \ 143 SCTP_ST_## _name (_type _arg) \ 144 { sctp_subtype_t _retval; _retval._elt = _arg; return _retval; } 145 146 SCTP_SUBTYPE_CONSTRUCTOR(CHUNK, sctp_cid_t, chunk) 147 SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT, sctp_event_timeout_t, timeout) 148 SCTP_SUBTYPE_CONSTRUCTOR(OTHER, sctp_event_other_t, other) 149 SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE, sctp_event_primitive_t, primitive) 150 151 152 #define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA) 153 154 /* Calculate the actual data size in a data chunk */ 155 #define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end)\ 156 - (unsigned long)(c->chunk_hdr)\ 157 - sizeof(sctp_data_chunk_t))) 158 159 /* Internal error codes */ 160 typedef enum { 161 162 SCTP_IERROR_NO_ERROR = 0, 163 SCTP_IERROR_BASE = 1000, 164 SCTP_IERROR_NO_COOKIE, 165 SCTP_IERROR_BAD_SIG, 166 SCTP_IERROR_STALE_COOKIE, 167 SCTP_IERROR_NOMEM, 168 SCTP_IERROR_MALFORMED, 169 SCTP_IERROR_BAD_TAG, 170 SCTP_IERROR_BIG_GAP, 171 SCTP_IERROR_DUP_TSN, 172 SCTP_IERROR_HIGH_TSN, 173 SCTP_IERROR_IGNORE_TSN, 174 SCTP_IERROR_NO_DATA, 175 SCTP_IERROR_BAD_STREAM, 176 SCTP_IERROR_BAD_PORTS, 177 SCTP_IERROR_AUTH_BAD_HMAC, 178 SCTP_IERROR_AUTH_BAD_KEYID, 179 SCTP_IERROR_PROTO_VIOLATION, 180 SCTP_IERROR_ERROR, 181 SCTP_IERROR_ABORT, 182 } sctp_ierror_t; 183 184 185 186 /* SCTP state defines for internal state machine */ 187 typedef enum { 188 189 SCTP_STATE_CLOSED = 0, 190 SCTP_STATE_COOKIE_WAIT = 1, 191 SCTP_STATE_COOKIE_ECHOED = 2, 192 SCTP_STATE_ESTABLISHED = 3, 193 SCTP_STATE_SHUTDOWN_PENDING = 4, 194 SCTP_STATE_SHUTDOWN_SENT = 5, 195 SCTP_STATE_SHUTDOWN_RECEIVED = 6, 196 SCTP_STATE_SHUTDOWN_ACK_SENT = 7, 197 198 } sctp_state_t; 199 200 #define SCTP_STATE_MAX SCTP_STATE_SHUTDOWN_ACK_SENT 201 #define SCTP_STATE_NUM_STATES (SCTP_STATE_MAX + 1) 202 203 /* These are values for sk->state. 204 * For a UDP-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 and can initiate the creation of new ones. 209 * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off 210 * socket with one association. 211 * For a TCP-style SCTP socket, the states are defined as follows 212 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to 213 * accept new associations, but it can initiate the creation of new ones. 214 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to 215 * accept new associations, but cannot initiate the creation of new ones. 216 * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single 217 * association. 218 */ 219 typedef enum { 220 SCTP_SS_CLOSED = TCP_CLOSE, 221 SCTP_SS_LISTENING = TCP_LISTEN, 222 SCTP_SS_ESTABLISHING = TCP_SYN_SENT, 223 SCTP_SS_ESTABLISHED = TCP_ESTABLISHED, 224 SCTP_SS_CLOSING = TCP_CLOSING, 225 } sctp_sock_state_t; 226 227 /* These functions map various type to printable names. */ 228 const char *sctp_cname(const sctp_subtype_t); /* chunk types */ 229 const char *sctp_oname(const sctp_subtype_t); /* other events */ 230 const char *sctp_tname(const sctp_subtype_t); /* timeouts */ 231 const char *sctp_pname(const sctp_subtype_t); /* primitives */ 232 233 /* This is a table of printable names of sctp_state_t's. */ 234 extern const char *const sctp_state_tbl[]; 235 extern const char *const sctp_evttype_tbl[]; 236 extern const char *const sctp_status_tbl[]; 237 238 /* Maximum chunk length considering padding requirements. */ 239 enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) }; 240 241 /* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little 242 * harder (until reaching ESTABLISHED state). 243 */ 244 enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 }; 245 246 /* Guess at how big to make the TSN mapping array. 247 * We guarantee that we can handle at least this big a gap between the 248 * cumulative ACK and the highest TSN. In practice, we can often 249 * handle up to twice this value. 250 * 251 * NEVER make this more than 32767 (2^15-1). The Gap Ack Blocks in a 252 * SACK (see section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE 253 * must be less than 65535 (2^16 - 1), or we will have overflow 254 * problems creating SACK's. 255 */ 256 #define SCTP_TSN_MAP_INITIAL BITS_PER_LONG 257 #define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL 258 #define SCTP_TSN_MAP_SIZE 4096 259 260 /* We will not record more than this many duplicate TSNs between two 261 * SACKs. The minimum PMTU is 576. Remove all the headers and there 262 * is enough room for 131 duplicate reports. Round down to the 263 * nearest power of 2. 264 */ 265 enum { SCTP_MIN_PMTU = 576 }; 266 enum { SCTP_MAX_DUP_TSNS = 16 }; 267 enum { SCTP_MAX_GABS = 16 }; 268 269 /* Heartbeat interval - 30 secs */ 270 #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT (30*1000) 271 272 /* Delayed sack timer - 200ms */ 273 #define SCTP_DEFAULT_TIMEOUT_SACK (200) 274 275 /* RTO.Initial - 3 seconds 276 * RTO.Min - 1 second 277 * RTO.Max - 60 seconds 278 * RTO.Alpha - 1/8 279 * RTO.Beta - 1/4 280 */ 281 #define SCTP_RTO_INITIAL (3 * 1000) 282 #define SCTP_RTO_MIN (1 * 1000) 283 #define SCTP_RTO_MAX (60 * 1000) 284 285 #define SCTP_RTO_ALPHA 3 /* 1/8 when converted to right shifts. */ 286 #define SCTP_RTO_BETA 2 /* 1/4 when converted to right shifts. */ 287 288 /* Maximum number of new data packets that can be sent in a burst. */ 289 #define SCTP_DEFAULT_MAX_BURST 4 290 291 #define SCTP_CLOCK_GRANULARITY 1 /* 1 jiffy */ 292 293 #define SCTP_DEFAULT_COOKIE_LIFE (60 * 1000) /* 60 seconds */ 294 295 #define SCTP_DEFAULT_MINWINDOW 1500 /* default minimum rwnd size */ 296 #define SCTP_DEFAULT_MAXWINDOW 65535 /* default rwnd size */ 297 #define SCTP_DEFAULT_RWND_SHIFT 4 /* by default, update on 1/16 of 298 * rcvbuf, which is 1/8 of initial 299 * window 300 */ 301 #define SCTP_DEFAULT_MAXSEGMENT 1500 /* MTU size, this is the limit 302 * to which we will raise the P-MTU. 303 */ 304 #define SCTP_DEFAULT_MINSEGMENT 512 /* MTU size ... if no mtu disc */ 305 306 #define SCTP_SECRET_SIZE 32 /* Number of octets in a 256 bits. */ 307 308 #define SCTP_SIGNATURE_SIZE 20 /* size of a SLA-1 signature */ 309 310 #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash 311 * functions simpler to write. 312 */ 313 314 /* These return values describe the success or failure of a number of 315 * routines which form the lower interface to SCTP_outqueue. 316 */ 317 typedef enum { 318 SCTP_XMIT_OK, 319 SCTP_XMIT_PMTU_FULL, 320 SCTP_XMIT_RWND_FULL, 321 SCTP_XMIT_NAGLE_DELAY, 322 } sctp_xmit_t; 323 324 /* These are the commands for manipulating transports. */ 325 typedef enum { 326 SCTP_TRANSPORT_UP, 327 SCTP_TRANSPORT_DOWN, 328 SCTP_TRANSPORT_PF, 329 } sctp_transport_cmd_t; 330 331 /* These are the address scopes defined mainly for IPv4 addresses 332 * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>. 333 * These scopes are hopefully generic enough to be used on scoping both 334 * IPv4 and IPv6 addresses in SCTP. 335 * At this point, the IPv6 scopes will be mapped to these internal scopes 336 * as much as possible. 337 */ 338 typedef enum { 339 SCTP_SCOPE_GLOBAL, /* IPv4 global addresses */ 340 SCTP_SCOPE_PRIVATE, /* IPv4 private addresses */ 341 SCTP_SCOPE_LINK, /* IPv4 link local address */ 342 SCTP_SCOPE_LOOPBACK, /* IPv4 loopback address */ 343 SCTP_SCOPE_UNUSABLE, /* IPv4 unusable addresses */ 344 } sctp_scope_t; 345 346 typedef enum { 347 SCTP_SCOPE_POLICY_DISABLE, /* Disable IPv4 address scoping */ 348 SCTP_SCOPE_POLICY_ENABLE, /* Enable IPv4 address scoping */ 349 SCTP_SCOPE_POLICY_PRIVATE, /* Follow draft but allow IPv4 private addresses */ 350 SCTP_SCOPE_POLICY_LINK, /* Follow draft but allow IPv4 link local addresses */ 351 } sctp_scope_policy_t; 352 353 /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>, 354 * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24, 355 * 192.88.99.0/24. 356 * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP 357 * addresses. 358 */ 359 #define IS_IPV4_UNUSABLE_ADDRESS(a) \ 360 ((htonl(INADDR_BROADCAST) == a) || \ 361 ipv4_is_multicast(a) || \ 362 ipv4_is_zeronet(a) || \ 363 ipv4_is_test_198(a) || \ 364 ipv4_is_anycast_6to4(a)) 365 366 /* Flags used for the bind address copy functions. */ 367 #define SCTP_ADDR6_ALLOWED 0x00000001 /* IPv6 address is allowed by 368 local sock family */ 369 #define SCTP_ADDR4_PEERSUPP 0x00000002 /* IPv4 address is supported by 370 peer */ 371 #define SCTP_ADDR6_PEERSUPP 0x00000004 /* IPv6 address is supported by 372 peer */ 373 374 /* Reasons to retransmit. */ 375 typedef enum { 376 SCTP_RTXR_T3_RTX, 377 SCTP_RTXR_FAST_RTX, 378 SCTP_RTXR_PMTUD, 379 SCTP_RTXR_T1_RTX, 380 } sctp_retransmit_reason_t; 381 382 /* Reasons to lower cwnd. */ 383 typedef enum { 384 SCTP_LOWER_CWND_T3_RTX, 385 SCTP_LOWER_CWND_FAST_RTX, 386 SCTP_LOWER_CWND_ECNE, 387 SCTP_LOWER_CWND_INACTIVE, 388 } sctp_lower_cwnd_t; 389 390 391 /* SCTP-AUTH Necessary constants */ 392 393 /* SCTP-AUTH, Section 3.3 394 * 395 * The following Table 2 shows the currently defined values for HMAC 396 * identifiers. 397 * 398 * +-----------------+--------------------------+ 399 * | HMAC Identifier | Message Digest Algorithm | 400 * +-----------------+--------------------------+ 401 * | 0 | Reserved | 402 * | 1 | SHA-1 defined in [8] | 403 * | 2 | Reserved | 404 * | 3 | SHA-256 defined in [8] | 405 * +-----------------+--------------------------+ 406 */ 407 enum { 408 SCTP_AUTH_HMAC_ID_RESERVED_0, 409 SCTP_AUTH_HMAC_ID_SHA1, 410 SCTP_AUTH_HMAC_ID_RESERVED_2, 411 #if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE) 412 SCTP_AUTH_HMAC_ID_SHA256, 413 #endif 414 __SCTP_AUTH_HMAC_MAX 415 }; 416 417 #define SCTP_AUTH_HMAC_ID_MAX __SCTP_AUTH_HMAC_MAX - 1 418 #define SCTP_AUTH_NUM_HMACS __SCTP_AUTH_HMAC_MAX 419 #define SCTP_SHA1_SIG_SIZE 20 420 #define SCTP_SHA256_SIG_SIZE 32 421 422 /* SCTP-AUTH, Section 3.2 423 * The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks 424 * MUST NOT be listed in the CHUNKS parameter 425 */ 426 #define SCTP_NUM_NOAUTH_CHUNKS 4 427 #define SCTP_AUTH_MAX_CHUNKS (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS) 428 429 /* SCTP-AUTH Section 6.1 430 * The RANDOM parameter MUST contain a 32 byte random number. 431 */ 432 #define SCTP_AUTH_RANDOM_LENGTH 32 433 434 #endif /* __sctp_constants_h__ */ 435