include/net/sctp/constants.h

   1 /* SCTP kernel reference 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 reference Implementation
   8  *
   9  * The SCTP reference 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  * The SCTP reference 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/tcp.h>  /* For TCP states used in sctp_sock_state_t */
  51 #include <linux/sctp.h>
  52 #include <linux/ipv6.h> /* For ipv6hdr. */
  53 #include <net/sctp/user.h>
  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 #define SCTP_CID_MAX                    SCTP_CID_ASCONF_ACK
  65
  66 #define SCTP_NUM_BASE_CHUNK_TYPES       (SCTP_CID_BASE_MAX + 1)
  67 #define SCTP_NUM_CHUNK_TYPES            (SCTP_NUM_BASE_CHUNKTYPES + 2)
  68
  69 #define SCTP_NUM_ADDIP_CHUNK_TYPES      2
  70
  71 #define SCTP_NUM_PRSCTP_CHUNK_TYPES     1
  72
  73 /* These are the different flavours of event.  */
  74 typedef enum {
  75
  76         SCTP_EVENT_T_CHUNK = 1,
  77         SCTP_EVENT_T_TIMEOUT,
  78         SCTP_EVENT_T_OTHER,
  79         SCTP_EVENT_T_PRIMITIVE
  80
  81 } sctp_event_t;
  82
  83 #define SCTP_EVENT_T_MAX SCTP_EVENT_T_PRIMITIVE
  84 #define SCTP_EVENT_T_NUM (SCTP_EVENT_T_MAX + 1)
  85
  86 /* As a convenience for the state machine, we append SCTP_EVENT_* and
  87  * SCTP_ULP_* to the list of possible chunks.
  88  */
  89
  90 typedef enum {
  91         SCTP_EVENT_TIMEOUT_NONE = 0,
  92         SCTP_EVENT_TIMEOUT_T1_COOKIE,
  93         SCTP_EVENT_TIMEOUT_T1_INIT,
  94         SCTP_EVENT_TIMEOUT_T2_SHUTDOWN,
  95         SCTP_EVENT_TIMEOUT_T3_RTX,
  96         SCTP_EVENT_TIMEOUT_T4_RTO,
  97         SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD,
  98         SCTP_EVENT_TIMEOUT_HEARTBEAT,
  99         SCTP_EVENT_TIMEOUT_SACK,
 100         SCTP_EVENT_TIMEOUT_AUTOCLOSE,
 101 } sctp_event_timeout_t;
 102
 103 #define SCTP_EVENT_TIMEOUT_MAX          SCTP_EVENT_TIMEOUT_AUTOCLOSE
 104 #define SCTP_NUM_TIMEOUT_TYPES          (SCTP_EVENT_TIMEOUT_MAX + 1)
 105
 106 typedef enum {
 107         SCTP_EVENT_NO_PENDING_TSN = 0,
 108 } sctp_event_other_t;
 109
 110 #define SCTP_EVENT_OTHER_MAX            SCTP_EVENT_NO_PENDING_TSN
 111 #define SCTP_NUM_OTHER_TYPES            (SCTP_EVENT_OTHER_MAX + 1)
 112
 113 /* These are primitive requests from the ULP.  */
 114 typedef enum {
 115         SCTP_PRIMITIVE_ASSOCIATE = 0,
 116         SCTP_PRIMITIVE_SHUTDOWN,
 117         SCTP_PRIMITIVE_ABORT,
 118         SCTP_PRIMITIVE_SEND,
 119         SCTP_PRIMITIVE_REQUESTHEARTBEAT,
 120         SCTP_PRIMITIVE_ASCONF,
 121 } sctp_event_primitive_t;
 122
 123 #define SCTP_EVENT_PRIMITIVE_MAX        SCTP_PRIMITIVE_ASCONF
 124 #define SCTP_NUM_PRIMITIVE_TYPES        (SCTP_EVENT_PRIMITIVE_MAX + 1)
 125
 126 /* We define here a utility type for manipulating subtypes.
 127  * The subtype constructors all work like this:
 128  *
 129  *      sctp_subtype_t foo = SCTP_ST_CHUNK(SCTP_CID_INIT);
 130  */
 131
 132 typedef union {
 133         sctp_cid_t chunk;
 134         sctp_event_timeout_t timeout;
 135         sctp_event_other_t other;
 136         sctp_event_primitive_t primitive;
 137 } sctp_subtype_t;
 138
 139 #define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \
 140 static inline sctp_subtype_t    \
 141 SCTP_ST_## _name (_type _arg)           \
 142 { sctp_subtype_t _retval; _retval._elt = _arg; return _retval; }
 143
 144 SCTP_SUBTYPE_CONSTRUCTOR(CHUNK,         sctp_cid_t,             chunk)
 145 SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT,       sctp_event_timeout_t,   timeout)
 146 SCTP_SUBTYPE_CONSTRUCTOR(OTHER,         sctp_event_other_t,     other)
 147 SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE,     sctp_event_primitive_t, primitive)
 148
 149
 150 #define sctp_chunk_is_control(a) (a->chunk_hdr->type != SCTP_CID_DATA)
 151 #define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA)
 152
 153 /* Calculate the actual data size in a data chunk */
 154 #define SCTP_DATA_SNDSIZE(c) ((int)((unsigned long)(c->chunk_end)\
 155                                 - (unsigned long)(c->chunk_hdr)\
 156                                 - sizeof(sctp_data_chunk_t)))
 157
 158 /* This is a table of printable names of sctp_param_t's.  */
 159 extern const char *sctp_param_tbl[];
 160
 161
 162 #define SCTP_MAX_ERROR_CAUSE  SCTP_ERROR_NONEXIST_IP
 163 #define SCTP_NUM_ERROR_CAUSE  10
 164
 165 /* Internal error codes */
 166 typedef enum {
 167
 168         SCTP_IERROR_NO_ERROR            = 0,
 169         SCTP_IERROR_BASE                = 1000,
 170         SCTP_IERROR_NO_COOKIE,
 171         SCTP_IERROR_BAD_SIG,
 172         SCTP_IERROR_STALE_COOKIE,
 173         SCTP_IERROR_NOMEM,
 174         SCTP_IERROR_MALFORMED,
 175         SCTP_IERROR_BAD_TAG,
 176         SCTP_IERROR_BIG_GAP,
 177         SCTP_IERROR_DUP_TSN,
 178         SCTP_IERROR_HIGH_TSN,
 179         SCTP_IERROR_IGNORE_TSN,
 180         SCTP_IERROR_NO_DATA,
 181         SCTP_IERROR_BAD_STREAM,
 182
 183 } sctp_ierror_t;
 184
 185
 186
 187 /* SCTP state defines for internal state machine */
 188 typedef enum {
 189
 190         SCTP_STATE_EMPTY                = 0,
 191         SCTP_STATE_CLOSED               = 1,
 192         SCTP_STATE_COOKIE_WAIT          = 2,
 193         SCTP_STATE_COOKIE_ECHOED        = 3,
 194         SCTP_STATE_ESTABLISHED          = 4,
 195         SCTP_STATE_SHUTDOWN_PENDING     = 5,
 196         SCTP_STATE_SHUTDOWN_SENT        = 6,
 197         SCTP_STATE_SHUTDOWN_RECEIVED    = 7,
 198         SCTP_STATE_SHUTDOWN_ACK_SENT    = 8,
 199
 200 } sctp_state_t;
 201
 202 #define SCTP_STATE_MAX                  SCTP_STATE_SHUTDOWN_ACK_SENT
 203 #define SCTP_STATE_NUM_STATES           (SCTP_STATE_MAX + 1)
 204
 205 /* These are values for sk->state.
 206  * For a UDP-style SCTP socket, the states are defined as follows
 207  * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
 208  *   accept new associations, but it can initiate the creation of new ones.
 209  * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
 210  *   accept new  associations and can initiate the creation of new ones.
 211  * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off
 212  *   socket with one association.
 213  * For a TCP-style SCTP socket, the states are defined as follows
 214  * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to
 215  *   accept new associations, but it can initiate the creation of new ones.
 216  * - A socket in SCTP_SS_LISTENING state indicates that it is willing to
 217  *   accept new associations, but cannot initiate the creation of new ones.
 218  * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single
 219  *   association.
 220  */
 221 typedef enum {
 222         SCTP_SS_CLOSED         = TCP_CLOSE,
 223         SCTP_SS_LISTENING      = TCP_LISTEN,
 224         SCTP_SS_ESTABLISHING   = TCP_SYN_SENT,
 225         SCTP_SS_ESTABLISHED    = TCP_ESTABLISHED,
 226         SCTP_SS_DISCONNECTING  = TCP_CLOSING,
 227 } sctp_sock_state_t;
 228
 229 /* These functions map various type to printable names.  */
 230 const char *sctp_cname(const sctp_subtype_t);   /* chunk types */
 231 const char *sctp_oname(const sctp_subtype_t);   /* other events */
 232 const char *sctp_tname(const sctp_subtype_t);   /* timeouts */
 233 const char *sctp_pname(const sctp_subtype_t);   /* primitives */
 234
 235 /* This is a table of printable names of sctp_state_t's.  */
 236 extern const char *sctp_state_tbl[], *sctp_evttype_tbl[], *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_SIZE 2048
 257 #define SCTP_TSN_MAX_GAP  65535
 258
 259 /* We will not record more than this many duplicate TSNs between two
 260  * SACKs.  The minimum PMTU is 576.  Remove all the headers and there
 261  * is enough room for 131 duplicate reports.  Round down to the
 262  * nearest power of 2.
 263  */
 264 enum { SCTP_MIN_PMTU = 576 };
 265 enum { SCTP_MAX_DUP_TSNS = 16 };
 266 enum { SCTP_MAX_GABS = 16 };
 267
 268 typedef enum {
 269         SCTP_COUNTER_INIT_ERROR,
 270 } sctp_counter_t;
 271
 272 /* How many counters does an association need? */
 273 #define SCTP_NUMBER_COUNTERS    5
 274
 275 /* Here we define the default timers.  */
 276
 277 /* cookie timer def = ? seconds */
 278 #define SCTP_DEFAULT_TIMEOUT_T1_COOKIE  (3 * HZ)
 279
 280 /* init timer def = 3 seconds  */
 281 #define SCTP_DEFAULT_TIMEOUT_T1_INIT    (3 * HZ)
 282
 283 /* shutdown timer def = 300 ms */
 284 #define SCTP_DEFAULT_TIMEOUT_T2_SHUTDOWN ((300 * HZ) / 1000)
 285
 286 /* 0 seconds + RTO */
 287 #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT  (10 * HZ)
 288
 289 /* recv timer def = 200ms (in usec) */
 290 #define SCTP_DEFAULT_TIMEOUT_SACK       ((200 * HZ) / 1000)
 291 #define SCTP_DEFAULT_TIMEOUT_SACK_MAX   ((500 * HZ) / 1000) /* 500 ms */
 292
 293 /* RTO.Initial              - 3  seconds
 294  * RTO.Min                  - 1  second
 295  * RTO.Max                  - 60 seconds
 296  * RTO.Alpha                - 1/8
 297  * RTO.Beta                 - 1/4
 298  */
 299 #define SCTP_RTO_INITIAL        (3 * HZ)
 300 #define SCTP_RTO_MIN            (1 * HZ)
 301 #define SCTP_RTO_MAX            (60 * HZ)
 302
 303 #define SCTP_RTO_ALPHA          3   /* 1/8 when converted to right shifts. */
 304 #define SCTP_RTO_BETA           2   /* 1/4 when converted to right shifts. */
 305
 306 /* Maximum number of new data packets that can be sent in a burst.  */
 307 #define SCTP_MAX_BURST          4
 308
 309 #define SCTP_CLOCK_GRANULARITY  1       /* 1 jiffy */
 310
 311 #define SCTP_DEF_MAX_INIT 6
 312 #define SCTP_DEF_MAX_SEND 10
 313
 314 #define SCTP_DEFAULT_COOKIE_LIFE_SEC    60 /* seconds */
 315 #define SCTP_DEFAULT_COOKIE_LIFE_USEC   0  /* microseconds */
 316
 317 #define SCTP_DEFAULT_MINWINDOW  1500    /* default minimum rwnd size */
 318 #define SCTP_DEFAULT_MAXWINDOW  65535   /* default rwnd size */
 319 #define SCTP_DEFAULT_MAXSEGMENT 1500    /* MTU size, this is the limit
 320                                          * to which we will raise the P-MTU.
 321                                          */
 322 #define SCTP_DEFAULT_MINSEGMENT 512     /* MTU size ... if no mtu disc */
 323 #define SCTP_HOW_MANY_SECRETS 2         /* How many secrets I keep */
 324 #define SCTP_HOW_LONG_COOKIE_LIVE 3600  /* How many seconds the current
 325                                          * secret will live?
 326                                          */
 327 #define SCTP_SECRET_SIZE 32             /* Number of octets in a 256 bits. */
 328
 329 #define SCTP_SIGNATURE_SIZE 20          /* size of a SLA-1 signature */
 330
 331 #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash
 332                                  * functions simpler to write.
 333                                  */
 334
 335 #if defined (CONFIG_SCTP_HMAC_MD5)
 336 #define SCTP_COOKIE_HMAC_ALG "md5"
 337 #elif defined (CONFIG_SCTP_HMAC_SHA1)
 338 #define SCTP_COOKIE_HMAC_ALG "sha1"
 339 #else
 340 #define SCTP_COOKIE_HMAC_ALG NULL
 341 #endif
 342
 343 /* These return values describe the success or failure of a number of
 344  * routines which form the lower interface to SCTP_outqueue.
 345  */
 346 typedef enum {
 347         SCTP_XMIT_OK,
 348         SCTP_XMIT_PMTU_FULL,
 349         SCTP_XMIT_RWND_FULL,
 350         SCTP_XMIT_NAGLE_DELAY,
 351 } sctp_xmit_t;
 352
 353 /* These are the commands for manipulating transports.  */
 354 typedef enum {
 355         SCTP_TRANSPORT_UP,
 356         SCTP_TRANSPORT_DOWN,
 357 } sctp_transport_cmd_t;
 358
 359 /* These are the address scopes defined mainly for IPv4 addresses
 360  * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
 361  * These scopes are hopefully generic enough to be used on scoping both
 362  * IPv4 and IPv6 addresses in SCTP.
 363  * At this point, the IPv6 scopes will be mapped to these internal scopes
 364  * as much as possible.
 365  */
 366 typedef enum {
 367         SCTP_SCOPE_GLOBAL,              /* IPv4 global addresses */
 368         SCTP_SCOPE_PRIVATE,             /* IPv4 private addresses */
 369         SCTP_SCOPE_LINK,                /* IPv4 link local address */
 370         SCTP_SCOPE_LOOPBACK,            /* IPv4 loopback address */
 371         SCTP_SCOPE_UNUSABLE,            /* IPv4 unusable addresses */
 372 } sctp_scope_t;
 373
 374 /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>,
 375  * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 198.18.0.0/24,
 376  * 192.88.99.0/24.
 377  * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP
 378  * addresses.
 379  */
 380 #define IS_IPV4_UNUSABLE_ADDRESS(a) \
 381         ((INADDR_BROADCAST == *a) || \
 382         (MULTICAST(*a)) || \
 383         (((unsigned char *)(a))[0] == 0) || \
 384         ((((unsigned char *)(a))[0] == 198) && \
 385         (((unsigned char *)(a))[1] == 18) && \
 386         (((unsigned char *)(a))[2] == 0)) || \
 387         ((((unsigned char *)(a))[0] == 192) && \
 388         (((unsigned char *)(a))[1] == 88) && \
 389         (((unsigned char *)(a))[2] == 99)))
 390
 391 /* IPv4 Link-local addresses: 169.254.0.0/16.  */
 392 #define IS_IPV4_LINK_ADDRESS(a) \
 393         ((((unsigned char *)(a))[0] == 169) && \
 394         (((unsigned char *)(a))[1] == 254))
 395
 396 /* RFC 1918 "Address Allocation for Private Internets" defines the IPv4
 397  * private address space as the following:
 398  *
 399  * 10.0.0.0 - 10.255.255.255 (10/8 prefix)
 400  * 172.16.0.0.0 - 172.31.255.255 (172.16/12 prefix)
 401  * 192.168.0.0 - 192.168.255.255 (192.168/16 prefix)
 402  */
 403 #define IS_IPV4_PRIVATE_ADDRESS(a) \
 404         ((((unsigned char *)(a))[0] == 10) || \
 405         ((((unsigned char *)(a))[0] == 172) && \
 406         (((unsigned char *)(a))[1] >= 16) && \
 407         (((unsigned char *)(a))[1] < 32)) || \
 408         ((((unsigned char *)(a))[0] == 192) && \
 409         (((unsigned char *)(a))[1] == 168)))
 410
 411 /* Flags used for the bind address copy functions.  */
 412 #define SCTP_ADDR6_ALLOWED      0x00000001      /* IPv6 address is allowed by
 413                                                    local sock family */
 414 #define SCTP_ADDR4_PEERSUPP     0x00000002      /* IPv4 address is supported by
 415                                                    peer */
 416 #define SCTP_ADDR6_PEERSUPP     0x00000004      /* IPv6 address is supported by
 417                                                    peer */
 418
 419 /* Reasons to retransmit. */
 420 typedef enum {
 421         SCTP_RTXR_T3_RTX,
 422         SCTP_RTXR_FAST_RTX,
 423         SCTP_RTXR_PMTUD,
 424 } sctp_retransmit_reason_t;
 425
 426 /* Reasons to lower cwnd. */
 427 typedef enum {
 428         SCTP_LOWER_CWND_T3_RTX,
 429         SCTP_LOWER_CWND_FAST_RTX,
 430         SCTP_LOWER_CWND_ECNE,
 431         SCTP_LOWER_CWND_INACTIVE,
 432 } sctp_lower_cwnd_t;
 433
 434 #endif /* __sctp_constants_h__ */