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 <linux-sctp@vger.kernel.org> 29 * 30 * Written or modified by: 31 * La Monte H.P. Yarroll <piggy@acm.org> 32 * Karl Knutson <karl@athena.chicago.il.us> 33 * Randall Stewart <randall@stewart.chicago.il.us> 34 * Ken Morneau <kmorneau@cisco.com> 35 * Qiaobing Xie <qxie1@motorola.com> 36 * Xingang Guo <xingang.guo@intel.com> 37 * Sridhar Samudrala <samudrala@us.ibm.com> 38 * Daisy Chang <daisyc@us.ibm.com> 39 */ 40 41 #ifndef __sctp_constants_h__ 42 #define __sctp_constants_h__ 43 44 #include <linux/sctp.h> 45 #include <linux/ipv6.h> /* For ipv6hdr. */ 46 #include <net/tcp_states.h> /* For TCP states used in sctp_sock_state_t */ 47 48 /* Value used for stream negotiation. */ 49 enum { SCTP_MAX_STREAM = 0xffff }; 50 enum { SCTP_DEFAULT_OUTSTREAMS = 10 }; 51 enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM }; 52 53 /* Since CIDs are sparse, we need all four of the following 54 * symbols. CIDs are dense through SCTP_CID_BASE_MAX. 55 */ 56 #define SCTP_CID_BASE_MAX SCTP_CID_SHUTDOWN_COMPLETE 57 58 #define SCTP_NUM_BASE_CHUNK_TYPES (SCTP_CID_BASE_MAX + 1) 59 60 #define SCTP_NUM_ADDIP_CHUNK_TYPES 2 61 62 #define SCTP_NUM_PRSCTP_CHUNK_TYPES 1 63 64 #define SCTP_NUM_AUTH_CHUNK_TYPES 1 65 66 #define SCTP_NUM_CHUNK_TYPES (SCTP_NUM_BASE_CHUNK_TYPES + \ 67 SCTP_NUM_ADDIP_CHUNK_TYPES +\ 68 SCTP_NUM_PRSCTP_CHUNK_TYPES +\ 69 SCTP_NUM_AUTH_CHUNK_TYPES) 70 71 /* These are the different flavours of event. */ 72 typedef enum { 73 74 SCTP_EVENT_T_CHUNK = 1, 75 SCTP_EVENT_T_TIMEOUT, 76 SCTP_EVENT_T_OTHER, 77 SCTP_EVENT_T_PRIMITIVE 78 79 } sctp_event_t; 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 typedef enum { 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_SACK, 95 SCTP_EVENT_TIMEOUT_AUTOCLOSE, 96 } sctp_event_timeout_t; 97 98 #define SCTP_EVENT_TIMEOUT_MAX SCTP_EVENT_TIMEOUT_AUTOCLOSE 99 #define SCTP_NUM_TIMEOUT_TYPES (SCTP_EVENT_TIMEOUT_MAX + 1) 100 101 typedef enum { 102 SCTP_EVENT_NO_PENDING_TSN = 0, 103 SCTP_EVENT_ICMP_PROTO_UNREACH, 104 } sctp_event_other_t; 105 106 #define SCTP_EVENT_OTHER_MAX SCTP_EVENT_ICMP_PROTO_UNREACH 107 #define SCTP_NUM_OTHER_TYPES (SCTP_EVENT_OTHER_MAX + 1) 108 109 /* These are primitive requests from the ULP. */ 110 typedef enum { 111 SCTP_PRIMITIVE_ASSOCIATE = 0, 112 SCTP_PRIMITIVE_SHUTDOWN, 113 SCTP_PRIMITIVE_ABORT, 114 SCTP_PRIMITIVE_SEND, 115 SCTP_PRIMITIVE_REQUESTHEARTBEAT, 116 SCTP_PRIMITIVE_ASCONF, 117 } sctp_event_primitive_t; 118 119 #define SCTP_EVENT_PRIMITIVE_MAX SCTP_PRIMITIVE_ASCONF 120 #define SCTP_NUM_PRIMITIVE_TYPES (SCTP_EVENT_PRIMITIVE_MAX + 1) 121 122 /* We define here a utility type for manipulating subtypes. 123 * The subtype constructors all work like this: 124 * 125 * sctp_subtype_t foo = SCTP_ST_CHUNK(SCTP_CID_INIT); 126 */ 127 128 typedef union { 129 sctp_cid_t chunk; 130 sctp_event_timeout_t timeout; 131 sctp_event_other_t other; 132 sctp_event_primitive_t primitive; 133 } sctp_subtype_t; 134 135 #define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \ 136 static inline sctp_subtype_t \ 137 SCTP_ST_## _name (_type _arg) \ 138 { sctp_subtype_t _retval; _retval._elt = _arg; return _retval; } 139 140 SCTP_SUBTYPE_CONSTRUCTOR(CHUNK, sctp_cid_t, chunk) 141 SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT, sctp_event_timeout_t, timeout) 142 SCTP_SUBTYPE_CONSTRUCTOR(OTHER, sctp_event_other_t, other) 143 SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE, sctp_event_primitive_t, primitive) 144 145 146 #define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA) 147 148 /* Calculate the actual data size in a data chunk */ 149 #define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end)\ 150 - (unsigned long)(c->chunk_hdr)\ 151 - sizeof(sctp_data_chunk_t))) 152 153 /* Internal error codes */ 154 typedef enum { 155 156 SCTP_IERROR_NO_ERROR = 0, 157 SCTP_IERROR_BASE = 1000, 158 SCTP_IERROR_NO_COOKIE, 159 SCTP_IERROR_BAD_SIG, 160 SCTP_IERROR_STALE_COOKIE, 161 SCTP_IERROR_NOMEM, 162 SCTP_IERROR_MALFORMED, 163 SCTP_IERROR_BAD_TAG, 164 SCTP_IERROR_BIG_GAP, 165 SCTP_IERROR_DUP_TSN, 166 SCTP_IERROR_HIGH_TSN, 167 SCTP_IERROR_IGNORE_TSN, 168 SCTP_IERROR_NO_DATA, 169 SCTP_IERROR_BAD_STREAM, 170 SCTP_IERROR_BAD_PORTS, 171 SCTP_IERROR_AUTH_BAD_HMAC, 172 SCTP_IERROR_AUTH_BAD_KEYID, 173 SCTP_IERROR_PROTO_VIOLATION, 174 SCTP_IERROR_ERROR, 175 SCTP_IERROR_ABORT, 176 } sctp_ierror_t; 177 178 179 180 /* SCTP state defines for internal state machine */ 181 typedef enum { 182 183 SCTP_STATE_CLOSED = 0, 184 SCTP_STATE_COOKIE_WAIT = 1, 185 SCTP_STATE_COOKIE_ECHOED = 2, 186 SCTP_STATE_ESTABLISHED = 3, 187 SCTP_STATE_SHUTDOWN_PENDING = 4, 188 SCTP_STATE_SHUTDOWN_SENT = 5, 189 SCTP_STATE_SHUTDOWN_RECEIVED = 6, 190 SCTP_STATE_SHUTDOWN_ACK_SENT = 7, 191 192 } sctp_state_t; 193 194 #define SCTP_STATE_MAX SCTP_STATE_SHUTDOWN_ACK_SENT 195 #define SCTP_STATE_NUM_STATES (SCTP_STATE_MAX + 1) 196 197 /* These are values for sk->state. 198 * For a UDP-style SCTP socket, the states are defined as follows 199 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to 200 * accept new associations, but it can initiate the creation of new ones. 201 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to 202 * accept new associations and can initiate the creation of new ones. 203 * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off 204 * socket with one association. 205 * For a TCP-style SCTP socket, the states are defined as follows 206 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to 207 * accept new associations, but it can initiate the creation of new ones. 208 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to 209 * accept new associations, but cannot initiate the creation of new ones. 210 * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single 211 * association. 212 */ 213 typedef enum { 214 SCTP_SS_CLOSED = TCP_CLOSE, 215 SCTP_SS_LISTENING = TCP_LISTEN, 216 SCTP_SS_ESTABLISHING = TCP_SYN_SENT, 217 SCTP_SS_ESTABLISHED = TCP_ESTABLISHED, 218 SCTP_SS_CLOSING = TCP_CLOSING, 219 } sctp_sock_state_t; 220 221 /* These functions map various type to printable names. */ 222 const char *sctp_cname(const sctp_subtype_t); /* chunk types */ 223 const char *sctp_oname(const sctp_subtype_t); /* other events */ 224 const char *sctp_tname(const sctp_subtype_t); /* timeouts */ 225 const char *sctp_pname(const sctp_subtype_t); /* primitives */ 226 227 /* This is a table of printable names of sctp_state_t's. */ 228 extern const char *const sctp_state_tbl[]; 229 extern const char *const sctp_evttype_tbl[]; 230 extern const char *const sctp_status_tbl[]; 231 232 /* Maximum chunk length considering padding requirements. */ 233 enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) }; 234 235 /* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little 236 * harder (until reaching ESTABLISHED state). 237 */ 238 enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 }; 239 240 /* Guess at how big to make the TSN mapping array. 241 * We guarantee that we can handle at least this big a gap between the 242 * cumulative ACK and the highest TSN. In practice, we can often 243 * handle up to twice this value. 244 * 245 * NEVER make this more than 32767 (2^15-1). The Gap Ack Blocks in a 246 * SACK (see section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE 247 * must be less than 65535 (2^16 - 1), or we will have overflow 248 * problems creating SACK's. 249 */ 250 #define SCTP_TSN_MAP_INITIAL BITS_PER_LONG 251 #define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL 252 #define SCTP_TSN_MAP_SIZE 4096 253 254 /* We will not record more than this many duplicate TSNs between two 255 * SACKs. The minimum PMTU is 576. Remove all the headers and there 256 * is enough room for 131 duplicate reports. Round down to the 257 * nearest power of 2. 258 */ 259 enum { SCTP_MIN_PMTU = 576 }; 260 enum { SCTP_MAX_DUP_TSNS = 16 }; 261 enum { SCTP_MAX_GABS = 16 }; 262 263 /* Heartbeat interval - 30 secs */ 264 #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT (30*1000) 265 266 /* Delayed sack timer - 200ms */ 267 #define SCTP_DEFAULT_TIMEOUT_SACK (200) 268 269 /* RTO.Initial - 3 seconds 270 * RTO.Min - 1 second 271 * RTO.Max - 60 seconds 272 * RTO.Alpha - 1/8 273 * RTO.Beta - 1/4 274 */ 275 #define SCTP_RTO_INITIAL (3 * 1000) 276 #define SCTP_RTO_MIN (1 * 1000) 277 #define SCTP_RTO_MAX (60 * 1000) 278 279 #define SCTP_RTO_ALPHA 3 /* 1/8 when converted to right shifts. */ 280 #define SCTP_RTO_BETA 2 /* 1/4 when converted to right shifts. */ 281 282 /* Maximum number of new data packets that can be sent in a burst. */ 283 #define SCTP_DEFAULT_MAX_BURST 4 284 285 #define SCTP_CLOCK_GRANULARITY 1 /* 1 jiffy */ 286 287 #define SCTP_DEFAULT_COOKIE_LIFE (60 * 1000) /* 60 seconds */ 288 289 #define SCTP_DEFAULT_MINWINDOW 1500 /* default minimum rwnd size */ 290 #define SCTP_DEFAULT_MAXWINDOW 65535 /* default rwnd size */ 291 #define SCTP_DEFAULT_RWND_SHIFT 4 /* by default, update on 1/16 of 292 * rcvbuf, which is 1/8 of initial 293 * window 294 */ 295 #define SCTP_DEFAULT_MAXSEGMENT 1500 /* MTU size, this is the limit 296 * to which we will raise the P-MTU. 297 */ 298 #define SCTP_DEFAULT_MINSEGMENT 512 /* MTU size ... if no mtu disc */ 299 300 #define SCTP_SECRET_SIZE 32 /* Number of octets in a 256 bits. */ 301 302 #define SCTP_SIGNATURE_SIZE 20 /* size of a SLA-1 signature */ 303 304 #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash 305 * functions simpler to write. 306 */ 307 308 /* These return values describe the success or failure of a number of 309 * routines which form the lower interface to SCTP_outqueue. 310 */ 311 typedef enum { 312 SCTP_XMIT_OK, 313 SCTP_XMIT_PMTU_FULL, 314 SCTP_XMIT_RWND_FULL, 315 SCTP_XMIT_NAGLE_DELAY, 316 } sctp_xmit_t; 317 318 /* These are the commands for manipulating transports. */ 319 typedef enum { 320 SCTP_TRANSPORT_UP, 321 SCTP_TRANSPORT_DOWN, 322 SCTP_TRANSPORT_PF, 323 } sctp_transport_cmd_t; 324 325 /* These are the address scopes defined mainly for IPv4 addresses 326 * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>. 327 * These scopes are hopefully generic enough to be used on scoping both 328 * IPv4 and IPv6 addresses in SCTP. 329 * At this point, the IPv6 scopes will be mapped to these internal scopes 330 * as much as possible. 331 */ 332 typedef enum { 333 SCTP_SCOPE_GLOBAL, /* IPv4 global addresses */ 334 SCTP_SCOPE_PRIVATE, /* IPv4 private addresses */ 335 SCTP_SCOPE_LINK, /* IPv4 link local address */ 336 SCTP_SCOPE_LOOPBACK, /* IPv4 loopback address */ 337 SCTP_SCOPE_UNUSABLE, /* IPv4 unusable addresses */ 338 } sctp_scope_t; 339 340 typedef enum { 341 SCTP_SCOPE_POLICY_DISABLE, /* Disable IPv4 address scoping */ 342 SCTP_SCOPE_POLICY_ENABLE, /* Enable IPv4 address scoping */ 343 SCTP_SCOPE_POLICY_PRIVATE, /* Follow draft but allow IPv4 private addresses */ 344 SCTP_SCOPE_POLICY_LINK, /* Follow draft but allow IPv4 link local addresses */ 345 } sctp_scope_policy_t; 346 347 /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>, 348 * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24, 349 * 192.88.99.0/24. 350 * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP 351 * addresses. 352 */ 353 #define IS_IPV4_UNUSABLE_ADDRESS(a) \ 354 ((htonl(INADDR_BROADCAST) == a) || \ 355 ipv4_is_multicast(a) || \ 356 ipv4_is_zeronet(a) || \ 357 ipv4_is_test_198(a) || \ 358 ipv4_is_anycast_6to4(a)) 359 360 /* Flags used for the bind address copy functions. */ 361 #define SCTP_ADDR6_ALLOWED 0x00000001 /* IPv6 address is allowed by 362 local sock family */ 363 #define SCTP_ADDR4_PEERSUPP 0x00000002 /* IPv4 address is supported by 364 peer */ 365 #define SCTP_ADDR6_PEERSUPP 0x00000004 /* IPv6 address is supported by 366 peer */ 367 368 /* Reasons to retransmit. */ 369 typedef enum { 370 SCTP_RTXR_T3_RTX, 371 SCTP_RTXR_FAST_RTX, 372 SCTP_RTXR_PMTUD, 373 SCTP_RTXR_T1_RTX, 374 } sctp_retransmit_reason_t; 375 376 /* Reasons to lower cwnd. */ 377 typedef enum { 378 SCTP_LOWER_CWND_T3_RTX, 379 SCTP_LOWER_CWND_FAST_RTX, 380 SCTP_LOWER_CWND_ECNE, 381 SCTP_LOWER_CWND_INACTIVE, 382 } sctp_lower_cwnd_t; 383 384 385 /* SCTP-AUTH Necessary constants */ 386 387 /* SCTP-AUTH, Section 3.3 388 * 389 * The following Table 2 shows the currently defined values for HMAC 390 * identifiers. 391 * 392 * +-----------------+--------------------------+ 393 * | HMAC Identifier | Message Digest Algorithm | 394 * +-----------------+--------------------------+ 395 * | 0 | Reserved | 396 * | 1 | SHA-1 defined in [8] | 397 * | 2 | Reserved | 398 * | 3 | SHA-256 defined in [8] | 399 * +-----------------+--------------------------+ 400 */ 401 enum { 402 SCTP_AUTH_HMAC_ID_RESERVED_0, 403 SCTP_AUTH_HMAC_ID_SHA1, 404 SCTP_AUTH_HMAC_ID_RESERVED_2, 405 #if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE) 406 SCTP_AUTH_HMAC_ID_SHA256, 407 #endif 408 __SCTP_AUTH_HMAC_MAX 409 }; 410 411 #define SCTP_AUTH_HMAC_ID_MAX __SCTP_AUTH_HMAC_MAX - 1 412 #define SCTP_AUTH_NUM_HMACS __SCTP_AUTH_HMAC_MAX 413 #define SCTP_SHA1_SIG_SIZE 20 414 #define SCTP_SHA256_SIG_SIZE 32 415 416 /* SCTP-AUTH, Section 3.2 417 * The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks 418 * MUST NOT be listed in the CHUNKS parameter 419 */ 420 #define SCTP_NUM_NOAUTH_CHUNKS 4 421 #define SCTP_AUTH_MAX_CHUNKS (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS) 422 423 /* SCTP-AUTH Section 6.1 424 * The RANDOM parameter MUST contain a 32 byte random number. 425 */ 426 #define SCTP_AUTH_RANDOM_LENGTH 32 427 428 #endif /* __sctp_constants_h__ */ 429