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/sctp/user.h> 53 #include <net/tcp_states.h> /* For TCP states used in sctp_sock_state_t */ 54 55 /* Value used for stream negotiation. */ 56 enum { SCTP_MAX_STREAM = 0xffff }; 57 enum { SCTP_DEFAULT_OUTSTREAMS = 10 }; 58 enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM }; 59 60 /* Since CIDs are sparse, we need all four of the following 61 * symbols. CIDs are dense through SCTP_CID_BASE_MAX. 62 */ 63 #define SCTP_CID_BASE_MAX SCTP_CID_SHUTDOWN_COMPLETE 64 65 #define SCTP_NUM_BASE_CHUNK_TYPES (SCTP_CID_BASE_MAX + 1) 66 67 #define SCTP_NUM_ADDIP_CHUNK_TYPES 2 68 69 #define SCTP_NUM_PRSCTP_CHUNK_TYPES 1 70 71 #define SCTP_NUM_AUTH_CHUNK_TYPES 1 72 73 #define SCTP_NUM_CHUNK_TYPES (SCTP_NUM_BASE_CHUNK_TYPES + \ 74 SCTP_NUM_ADDIP_CHUNK_TYPES +\ 75 SCTP_NUM_PRSCTP_CHUNK_TYPES +\ 76 SCTP_NUM_AUTH_CHUNK_TYPES) 77 78 /* These are the different flavours of event. */ 79 typedef enum { 80 81 SCTP_EVENT_T_CHUNK = 1, 82 SCTP_EVENT_T_TIMEOUT, 83 SCTP_EVENT_T_OTHER, 84 SCTP_EVENT_T_PRIMITIVE 85 86 } sctp_event_t; 87 88 /* As a convenience for the state machine, we append SCTP_EVENT_* and 89 * SCTP_ULP_* to the list of possible chunks. 90 */ 91 92 typedef enum { 93 SCTP_EVENT_TIMEOUT_NONE = 0, 94 SCTP_EVENT_TIMEOUT_T1_COOKIE, 95 SCTP_EVENT_TIMEOUT_T1_INIT, 96 SCTP_EVENT_TIMEOUT_T2_SHUTDOWN, 97 SCTP_EVENT_TIMEOUT_T3_RTX, 98 SCTP_EVENT_TIMEOUT_T4_RTO, 99 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD, 100 SCTP_EVENT_TIMEOUT_HEARTBEAT, 101 SCTP_EVENT_TIMEOUT_SACK, 102 SCTP_EVENT_TIMEOUT_AUTOCLOSE, 103 } sctp_event_timeout_t; 104 105 #define SCTP_EVENT_TIMEOUT_MAX SCTP_EVENT_TIMEOUT_AUTOCLOSE 106 #define SCTP_NUM_TIMEOUT_TYPES (SCTP_EVENT_TIMEOUT_MAX + 1) 107 108 typedef enum { 109 SCTP_EVENT_NO_PENDING_TSN = 0, 110 SCTP_EVENT_ICMP_PROTO_UNREACH, 111 } sctp_event_other_t; 112 113 #define SCTP_EVENT_OTHER_MAX SCTP_EVENT_ICMP_PROTO_UNREACH 114 #define SCTP_NUM_OTHER_TYPES (SCTP_EVENT_OTHER_MAX + 1) 115 116 /* These are primitive requests from the ULP. */ 117 typedef enum { 118 SCTP_PRIMITIVE_ASSOCIATE = 0, 119 SCTP_PRIMITIVE_SHUTDOWN, 120 SCTP_PRIMITIVE_ABORT, 121 SCTP_PRIMITIVE_SEND, 122 SCTP_PRIMITIVE_REQUESTHEARTBEAT, 123 SCTP_PRIMITIVE_ASCONF, 124 } sctp_event_primitive_t; 125 126 #define SCTP_EVENT_PRIMITIVE_MAX SCTP_PRIMITIVE_ASCONF 127 #define SCTP_NUM_PRIMITIVE_TYPES (SCTP_EVENT_PRIMITIVE_MAX + 1) 128 129 /* We define here a utility type for manipulating subtypes. 130 * The subtype constructors all work like this: 131 * 132 * sctp_subtype_t foo = SCTP_ST_CHUNK(SCTP_CID_INIT); 133 */ 134 135 typedef union { 136 sctp_cid_t chunk; 137 sctp_event_timeout_t timeout; 138 sctp_event_other_t other; 139 sctp_event_primitive_t primitive; 140 } sctp_subtype_t; 141 142 #define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \ 143 static inline sctp_subtype_t \ 144 SCTP_ST_## _name (_type _arg) \ 145 { sctp_subtype_t _retval; _retval._elt = _arg; return _retval; } 146 147 SCTP_SUBTYPE_CONSTRUCTOR(CHUNK, sctp_cid_t, chunk) 148 SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT, sctp_event_timeout_t, timeout) 149 SCTP_SUBTYPE_CONSTRUCTOR(OTHER, sctp_event_other_t, other) 150 SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE, sctp_event_primitive_t, primitive) 151 152 153 #define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA) 154 155 /* Calculate the actual data size in a data chunk */ 156 #define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end)\ 157 - (unsigned long)(c->chunk_hdr)\ 158 - sizeof(sctp_data_chunk_t))) 159 160 /* Internal error codes */ 161 typedef enum { 162 163 SCTP_IERROR_NO_ERROR = 0, 164 SCTP_IERROR_BASE = 1000, 165 SCTP_IERROR_NO_COOKIE, 166 SCTP_IERROR_BAD_SIG, 167 SCTP_IERROR_STALE_COOKIE, 168 SCTP_IERROR_NOMEM, 169 SCTP_IERROR_MALFORMED, 170 SCTP_IERROR_BAD_TAG, 171 SCTP_IERROR_BIG_GAP, 172 SCTP_IERROR_DUP_TSN, 173 SCTP_IERROR_HIGH_TSN, 174 SCTP_IERROR_IGNORE_TSN, 175 SCTP_IERROR_NO_DATA, 176 SCTP_IERROR_BAD_STREAM, 177 SCTP_IERROR_BAD_PORTS, 178 SCTP_IERROR_AUTH_BAD_HMAC, 179 SCTP_IERROR_AUTH_BAD_KEYID, 180 SCTP_IERROR_PROTO_VIOLATION, 181 SCTP_IERROR_ERROR, 182 SCTP_IERROR_ABORT, 183 } sctp_ierror_t; 184 185 186 187 /* SCTP state defines for internal state machine */ 188 typedef enum { 189 190 SCTP_STATE_CLOSED = 0, 191 SCTP_STATE_COOKIE_WAIT = 1, 192 SCTP_STATE_COOKIE_ECHOED = 2, 193 SCTP_STATE_ESTABLISHED = 3, 194 SCTP_STATE_SHUTDOWN_PENDING = 4, 195 SCTP_STATE_SHUTDOWN_SENT = 5, 196 SCTP_STATE_SHUTDOWN_RECEIVED = 6, 197 SCTP_STATE_SHUTDOWN_ACK_SENT = 7, 198 199 } sctp_state_t; 200 201 #define SCTP_STATE_MAX SCTP_STATE_SHUTDOWN_ACK_SENT 202 #define SCTP_STATE_NUM_STATES (SCTP_STATE_MAX + 1) 203 204 /* These are values for sk->state. 205 * For a UDP-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 and can initiate the creation of new ones. 210 * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off 211 * socket with one association. 212 * For a TCP-style SCTP socket, the states are defined as follows 213 * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to 214 * accept new associations, but it can initiate the creation of new ones. 215 * - A socket in SCTP_SS_LISTENING state indicates that it is willing to 216 * accept new associations, but cannot initiate the creation of new ones. 217 * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single 218 * association. 219 */ 220 typedef enum { 221 SCTP_SS_CLOSED = TCP_CLOSE, 222 SCTP_SS_LISTENING = TCP_LISTEN, 223 SCTP_SS_ESTABLISHING = TCP_SYN_SENT, 224 SCTP_SS_ESTABLISHED = TCP_ESTABLISHED, 225 SCTP_SS_CLOSING = TCP_CLOSING, 226 } sctp_sock_state_t; 227 228 /* These functions map various type to printable names. */ 229 const char *sctp_cname(const sctp_subtype_t); /* chunk types */ 230 const char *sctp_oname(const sctp_subtype_t); /* other events */ 231 const char *sctp_tname(const sctp_subtype_t); /* timeouts */ 232 const char *sctp_pname(const sctp_subtype_t); /* primitives */ 233 234 /* This is a table of printable names of sctp_state_t's. */ 235 extern const char *const sctp_state_tbl[]; 236 extern const char *const sctp_evttype_tbl[]; 237 extern const char *const sctp_status_tbl[]; 238 239 /* Maximum chunk length considering padding requirements. */ 240 enum { SCTP_MAX_CHUNK_LEN = ((1<<16) - sizeof(__u32)) }; 241 242 /* Encourage Cookie-Echo bundling by pre-fragmenting chunks a little 243 * harder (until reaching ESTABLISHED state). 244 */ 245 enum { SCTP_ARBITRARY_COOKIE_ECHO_LEN = 200 }; 246 247 /* Guess at how big to make the TSN mapping array. 248 * We guarantee that we can handle at least this big a gap between the 249 * cumulative ACK and the highest TSN. In practice, we can often 250 * handle up to twice this value. 251 * 252 * NEVER make this more than 32767 (2^15-1). The Gap Ack Blocks in a 253 * SACK (see section 3.3.4) are only 16 bits, so 2*SCTP_TSN_MAP_SIZE 254 * must be less than 65535 (2^16 - 1), or we will have overflow 255 * problems creating SACK's. 256 */ 257 #define SCTP_TSN_MAP_INITIAL BITS_PER_LONG 258 #define SCTP_TSN_MAP_INCREMENT SCTP_TSN_MAP_INITIAL 259 #define SCTP_TSN_MAP_SIZE 4096 260 261 /* We will not record more than this many duplicate TSNs between two 262 * SACKs. The minimum PMTU is 576. Remove all the headers and there 263 * is enough room for 131 duplicate reports. Round down to the 264 * nearest power of 2. 265 */ 266 enum { SCTP_MIN_PMTU = 576 }; 267 enum { SCTP_MAX_DUP_TSNS = 16 }; 268 enum { SCTP_MAX_GABS = 16 }; 269 270 /* Heartbeat interval - 30 secs */ 271 #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT (30*1000) 272 273 /* Delayed sack timer - 200ms */ 274 #define SCTP_DEFAULT_TIMEOUT_SACK (200) 275 276 /* RTO.Initial - 3 seconds 277 * RTO.Min - 1 second 278 * RTO.Max - 60 seconds 279 * RTO.Alpha - 1/8 280 * RTO.Beta - 1/4 281 */ 282 #define SCTP_RTO_INITIAL (3 * 1000) 283 #define SCTP_RTO_MIN (1 * 1000) 284 #define SCTP_RTO_MAX (60 * 1000) 285 286 #define SCTP_RTO_ALPHA 3 /* 1/8 when converted to right shifts. */ 287 #define SCTP_RTO_BETA 2 /* 1/4 when converted to right shifts. */ 288 289 /* Maximum number of new data packets that can be sent in a burst. */ 290 #define SCTP_DEFAULT_MAX_BURST 4 291 292 #define SCTP_CLOCK_GRANULARITY 1 /* 1 jiffy */ 293 294 #define SCTP_DEFAULT_COOKIE_LIFE (60 * 1000) /* 60 seconds */ 295 296 #define SCTP_DEFAULT_MINWINDOW 1500 /* default minimum rwnd size */ 297 #define SCTP_DEFAULT_MAXWINDOW 65535 /* default rwnd size */ 298 #define SCTP_DEFAULT_RWND_SHIFT 4 /* by default, update on 1/16 of 299 * rcvbuf, which is 1/8 of initial 300 * window 301 */ 302 #define SCTP_DEFAULT_MAXSEGMENT 1500 /* MTU size, this is the limit 303 * to which we will raise the P-MTU. 304 */ 305 #define SCTP_DEFAULT_MINSEGMENT 512 /* MTU size ... if no mtu disc */ 306 #define SCTP_HOW_MANY_SECRETS 2 /* How many secrets I keep */ 307 #define SCTP_SECRET_SIZE 32 /* Number of octets in a 256 bits. */ 308 309 #define SCTP_SIGNATURE_SIZE 20 /* size of a SLA-1 signature */ 310 311 #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash 312 * functions simpler to write. 313 */ 314 315 /* These return values describe the success or failure of a number of 316 * routines which form the lower interface to SCTP_outqueue. 317 */ 318 typedef enum { 319 SCTP_XMIT_OK, 320 SCTP_XMIT_PMTU_FULL, 321 SCTP_XMIT_RWND_FULL, 322 SCTP_XMIT_NAGLE_DELAY, 323 } sctp_xmit_t; 324 325 /* These are the commands for manipulating transports. */ 326 typedef enum { 327 SCTP_TRANSPORT_UP, 328 SCTP_TRANSPORT_DOWN, 329 SCTP_TRANSPORT_PF, 330 } sctp_transport_cmd_t; 331 332 /* These are the address scopes defined mainly for IPv4 addresses 333 * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>. 334 * These scopes are hopefully generic enough to be used on scoping both 335 * IPv4 and IPv6 addresses in SCTP. 336 * At this point, the IPv6 scopes will be mapped to these internal scopes 337 * as much as possible. 338 */ 339 typedef enum { 340 SCTP_SCOPE_GLOBAL, /* IPv4 global addresses */ 341 SCTP_SCOPE_PRIVATE, /* IPv4 private addresses */ 342 SCTP_SCOPE_LINK, /* IPv4 link local address */ 343 SCTP_SCOPE_LOOPBACK, /* IPv4 loopback address */ 344 SCTP_SCOPE_UNUSABLE, /* IPv4 unusable addresses */ 345 } sctp_scope_t; 346 347 typedef enum { 348 SCTP_SCOPE_POLICY_DISABLE, /* Disable IPv4 address scoping */ 349 SCTP_SCOPE_POLICY_ENABLE, /* Enable IPv4 address scoping */ 350 SCTP_SCOPE_POLICY_PRIVATE, /* Follow draft but allow IPv4 private addresses */ 351 SCTP_SCOPE_POLICY_LINK, /* Follow draft but allow IPv4 link local addresses */ 352 } sctp_scope_policy_t; 353 354 /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>, 355 * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24, 356 * 192.88.99.0/24. 357 * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP 358 * addresses. 359 */ 360 #define IS_IPV4_UNUSABLE_ADDRESS(a) \ 361 ((htonl(INADDR_BROADCAST) == a) || \ 362 ipv4_is_multicast(a) || \ 363 ipv4_is_zeronet(a) || \ 364 ipv4_is_test_198(a) || \ 365 ipv4_is_anycast_6to4(a)) 366 367 /* Flags used for the bind address copy functions. */ 368 #define SCTP_ADDR6_ALLOWED 0x00000001 /* IPv6 address is allowed by 369 local sock family */ 370 #define SCTP_ADDR4_PEERSUPP 0x00000002 /* IPv4 address is supported by 371 peer */ 372 #define SCTP_ADDR6_PEERSUPP 0x00000004 /* IPv6 address is supported by 373 peer */ 374 375 /* Reasons to retransmit. */ 376 typedef enum { 377 SCTP_RTXR_T3_RTX, 378 SCTP_RTXR_FAST_RTX, 379 SCTP_RTXR_PMTUD, 380 SCTP_RTXR_T1_RTX, 381 } sctp_retransmit_reason_t; 382 383 /* Reasons to lower cwnd. */ 384 typedef enum { 385 SCTP_LOWER_CWND_T3_RTX, 386 SCTP_LOWER_CWND_FAST_RTX, 387 SCTP_LOWER_CWND_ECNE, 388 SCTP_LOWER_CWND_INACTIVE, 389 } sctp_lower_cwnd_t; 390 391 392 /* SCTP-AUTH Necessary constants */ 393 394 /* SCTP-AUTH, Section 3.3 395 * 396 * The following Table 2 shows the currently defined values for HMAC 397 * identifiers. 398 * 399 * +-----------------+--------------------------+ 400 * | HMAC Identifier | Message Digest Algorithm | 401 * +-----------------+--------------------------+ 402 * | 0 | Reserved | 403 * | 1 | SHA-1 defined in [8] | 404 * | 2 | Reserved | 405 * | 3 | SHA-256 defined in [8] | 406 * +-----------------+--------------------------+ 407 */ 408 enum { 409 SCTP_AUTH_HMAC_ID_RESERVED_0, 410 SCTP_AUTH_HMAC_ID_SHA1, 411 SCTP_AUTH_HMAC_ID_RESERVED_2, 412 #if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE) 413 SCTP_AUTH_HMAC_ID_SHA256, 414 #endif 415 __SCTP_AUTH_HMAC_MAX 416 }; 417 418 #define SCTP_AUTH_HMAC_ID_MAX __SCTP_AUTH_HMAC_MAX - 1 419 #define SCTP_AUTH_NUM_HMACS __SCTP_AUTH_HMAC_MAX 420 #define SCTP_SHA1_SIG_SIZE 20 421 #define SCTP_SHA256_SIG_SIZE 32 422 423 /* SCTP-AUTH, Section 3.2 424 * The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks 425 * MUST NOT be listed in the CHUNKS parameter 426 */ 427 #define SCTP_NUM_NOAUTH_CHUNKS 4 428 #define SCTP_AUTH_MAX_CHUNKS (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS) 429 430 /* SCTP-AUTH Section 6.1 431 * The RANDOM parameter MUST contain a 32 byte random number. 432 */ 433 #define SCTP_AUTH_RANDOM_LENGTH 32 434 435 #endif /* __sctp_constants_h__ */ 436