1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | /* SCTP kernel implementation |
3 | * (C) Copyright IBM Corp. 2001, 2004 |
4 | * Copyright (c) 1999-2000 Cisco, Inc. |
5 | * Copyright (c) 1999-2001 Motorola, Inc. |
6 | * Copyright (c) 2001 Intel Corp. |
7 | * |
8 | * This file is part of the SCTP kernel implementation |
9 | * |
10 | * Please send any bug reports or fixes you make to the |
11 | * email address(es): |
12 | * lksctp developers <linux-sctp@vger.kernel.org> |
13 | * |
14 | * Written or modified by: |
15 | * La Monte H.P. Yarroll <piggy@acm.org> |
16 | * Karl Knutson <karl@athena.chicago.il.us> |
17 | * Randall Stewart <randall@stewart.chicago.il.us> |
18 | * Ken Morneau <kmorneau@cisco.com> |
19 | * Qiaobing Xie <qxie1@motorola.com> |
20 | * Xingang Guo <xingang.guo@intel.com> |
21 | * Sridhar Samudrala <samudrala@us.ibm.com> |
22 | * Daisy Chang <daisyc@us.ibm.com> |
23 | */ |
24 | |
25 | #ifndef __sctp_constants_h__ |
26 | #define __sctp_constants_h__ |
27 | |
28 | #include <linux/sctp.h> |
29 | #include <linux/ipv6.h> /* For ipv6hdr. */ |
30 | #include <net/tcp_states.h> /* For TCP states used in enum sctp_sock_state */ |
31 | |
32 | /* Value used for stream negotiation. */ |
33 | enum { SCTP_MAX_STREAM = 0xffff }; |
34 | enum { SCTP_DEFAULT_OUTSTREAMS = 10 }; |
35 | enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM }; |
36 | |
37 | /* Since CIDs are sparse, we need all four of the following |
38 | * symbols. CIDs are dense through SCTP_CID_BASE_MAX. |
39 | */ |
40 | #define SCTP_CID_BASE_MAX SCTP_CID_SHUTDOWN_COMPLETE |
41 | |
42 | #define SCTP_NUM_BASE_CHUNK_TYPES (SCTP_CID_BASE_MAX + 1) |
43 | |
44 | #define SCTP_NUM_ADDIP_CHUNK_TYPES 2 |
45 | |
46 | #define SCTP_NUM_PRSCTP_CHUNK_TYPES 1 |
47 | |
48 | #define SCTP_NUM_RECONF_CHUNK_TYPES 1 |
49 | |
50 | #define SCTP_NUM_AUTH_CHUNK_TYPES 1 |
51 | |
52 | #define SCTP_NUM_CHUNK_TYPES (SCTP_NUM_BASE_CHUNK_TYPES + \ |
53 | SCTP_NUM_ADDIP_CHUNK_TYPES +\ |
54 | SCTP_NUM_PRSCTP_CHUNK_TYPES +\ |
55 | SCTP_NUM_RECONF_CHUNK_TYPES +\ |
56 | SCTP_NUM_AUTH_CHUNK_TYPES) |
57 | |
58 | /* These are the different flavours of event. */ |
59 | enum sctp_event_type { |
60 | SCTP_EVENT_T_CHUNK = 1, |
61 | SCTP_EVENT_T_TIMEOUT, |
62 | SCTP_EVENT_T_OTHER, |
63 | SCTP_EVENT_T_PRIMITIVE |
64 | }; |
65 | |
66 | /* As a convenience for the state machine, we append SCTP_EVENT_* and |
67 | * SCTP_ULP_* to the list of possible chunks. |
68 | */ |
69 | |
70 | enum sctp_event_timeout { |
71 | SCTP_EVENT_TIMEOUT_NONE = 0, |
72 | SCTP_EVENT_TIMEOUT_T1_COOKIE, |
73 | SCTP_EVENT_TIMEOUT_T1_INIT, |
74 | SCTP_EVENT_TIMEOUT_T2_SHUTDOWN, |
75 | SCTP_EVENT_TIMEOUT_T3_RTX, |
76 | SCTP_EVENT_TIMEOUT_T4_RTO, |
77 | SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD, |
78 | SCTP_EVENT_TIMEOUT_HEARTBEAT, |
79 | SCTP_EVENT_TIMEOUT_RECONF, |
80 | SCTP_EVENT_TIMEOUT_PROBE, |
81 | SCTP_EVENT_TIMEOUT_SACK, |
82 | SCTP_EVENT_TIMEOUT_AUTOCLOSE, |
83 | }; |
84 | |
85 | #define SCTP_EVENT_TIMEOUT_MAX SCTP_EVENT_TIMEOUT_AUTOCLOSE |
86 | #define SCTP_NUM_TIMEOUT_TYPES (SCTP_EVENT_TIMEOUT_MAX + 1) |
87 | |
88 | enum sctp_event_other { |
89 | SCTP_EVENT_NO_PENDING_TSN = 0, |
90 | SCTP_EVENT_ICMP_PROTO_UNREACH, |
91 | }; |
92 | |
93 | #define SCTP_EVENT_OTHER_MAX SCTP_EVENT_ICMP_PROTO_UNREACH |
94 | #define SCTP_NUM_OTHER_TYPES (SCTP_EVENT_OTHER_MAX + 1) |
95 | |
96 | /* These are primitive requests from the ULP. */ |
97 | enum sctp_event_primitive { |
98 | SCTP_PRIMITIVE_ASSOCIATE = 0, |
99 | SCTP_PRIMITIVE_SHUTDOWN, |
100 | SCTP_PRIMITIVE_ABORT, |
101 | SCTP_PRIMITIVE_SEND, |
102 | SCTP_PRIMITIVE_REQUESTHEARTBEAT, |
103 | SCTP_PRIMITIVE_ASCONF, |
104 | SCTP_PRIMITIVE_RECONF, |
105 | }; |
106 | |
107 | #define SCTP_EVENT_PRIMITIVE_MAX SCTP_PRIMITIVE_RECONF |
108 | #define SCTP_NUM_PRIMITIVE_TYPES (SCTP_EVENT_PRIMITIVE_MAX + 1) |
109 | |
110 | /* We define here a utility type for manipulating subtypes. |
111 | * The subtype constructors all work like this: |
112 | * |
113 | * union sctp_subtype foo = SCTP_ST_CHUNK(SCTP_CID_INIT); |
114 | */ |
115 | |
116 | union sctp_subtype { |
117 | enum sctp_cid chunk; |
118 | enum sctp_event_timeout timeout; |
119 | enum sctp_event_other other; |
120 | enum sctp_event_primitive primitive; |
121 | }; |
122 | |
123 | #define SCTP_SUBTYPE_CONSTRUCTOR(_name, _type, _elt) \ |
124 | static inline union sctp_subtype \ |
125 | SCTP_ST_## _name (_type _arg) \ |
126 | { union sctp_subtype _retval; _retval._elt = _arg; return _retval; } |
127 | |
128 | SCTP_SUBTYPE_CONSTRUCTOR(CHUNK, enum sctp_cid, chunk) |
129 | SCTP_SUBTYPE_CONSTRUCTOR(TIMEOUT, enum sctp_event_timeout, timeout) |
130 | SCTP_SUBTYPE_CONSTRUCTOR(OTHER, enum sctp_event_other, other) |
131 | SCTP_SUBTYPE_CONSTRUCTOR(PRIMITIVE, enum sctp_event_primitive, primitive) |
132 | |
133 | |
134 | #define sctp_chunk_is_data(a) (a->chunk_hdr->type == SCTP_CID_DATA || \ |
135 | a->chunk_hdr->type == SCTP_CID_I_DATA) |
136 | |
137 | /* Internal error codes */ |
138 | enum sctp_ierror { |
139 | SCTP_IERROR_NO_ERROR = 0, |
140 | SCTP_IERROR_BASE = 1000, |
141 | SCTP_IERROR_NO_COOKIE, |
142 | SCTP_IERROR_BAD_SIG, |
143 | SCTP_IERROR_STALE_COOKIE, |
144 | SCTP_IERROR_NOMEM, |
145 | SCTP_IERROR_MALFORMED, |
146 | SCTP_IERROR_BAD_TAG, |
147 | SCTP_IERROR_BIG_GAP, |
148 | SCTP_IERROR_DUP_TSN, |
149 | SCTP_IERROR_HIGH_TSN, |
150 | SCTP_IERROR_IGNORE_TSN, |
151 | SCTP_IERROR_NO_DATA, |
152 | SCTP_IERROR_BAD_STREAM, |
153 | SCTP_IERROR_BAD_PORTS, |
154 | SCTP_IERROR_AUTH_BAD_HMAC, |
155 | SCTP_IERROR_AUTH_BAD_KEYID, |
156 | SCTP_IERROR_PROTO_VIOLATION, |
157 | SCTP_IERROR_ERROR, |
158 | SCTP_IERROR_ABORT, |
159 | }; |
160 | |
161 | |
162 | |
163 | /* SCTP state defines for internal state machine */ |
164 | enum sctp_state { |
165 | |
166 | SCTP_STATE_CLOSED = 0, |
167 | SCTP_STATE_COOKIE_WAIT = 1, |
168 | SCTP_STATE_COOKIE_ECHOED = 2, |
169 | SCTP_STATE_ESTABLISHED = 3, |
170 | SCTP_STATE_SHUTDOWN_PENDING = 4, |
171 | SCTP_STATE_SHUTDOWN_SENT = 5, |
172 | SCTP_STATE_SHUTDOWN_RECEIVED = 6, |
173 | SCTP_STATE_SHUTDOWN_ACK_SENT = 7, |
174 | |
175 | }; |
176 | |
177 | #define SCTP_STATE_MAX SCTP_STATE_SHUTDOWN_ACK_SENT |
178 | #define SCTP_STATE_NUM_STATES (SCTP_STATE_MAX + 1) |
179 | |
180 | /* These are values for sk->state. |
181 | * For a UDP-style SCTP socket, the states are defined as follows |
182 | * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to |
183 | * accept new associations, but it can initiate the creation of new ones. |
184 | * - A socket in SCTP_SS_LISTENING state indicates that it is willing to |
185 | * accept new associations and can initiate the creation of new ones. |
186 | * - A socket in SCTP_SS_ESTABLISHED state indicates that it is a peeled off |
187 | * socket with one association. |
188 | * For a TCP-style SCTP socket, the states are defined as follows |
189 | * - A socket in SCTP_SS_CLOSED state indicates that it is not willing to |
190 | * accept new associations, but it can initiate the creation of new ones. |
191 | * - A socket in SCTP_SS_LISTENING state indicates that it is willing to |
192 | * accept new associations, but cannot initiate the creation of new ones. |
193 | * - A socket in SCTP_SS_ESTABLISHED state indicates that it has a single |
194 | * association. |
195 | */ |
196 | enum sctp_sock_state { |
197 | SCTP_SS_CLOSED = TCP_CLOSE, |
198 | SCTP_SS_LISTENING = TCP_LISTEN, |
199 | SCTP_SS_ESTABLISHING = TCP_SYN_SENT, |
200 | SCTP_SS_ESTABLISHED = TCP_ESTABLISHED, |
201 | SCTP_SS_CLOSING = TCP_CLOSE_WAIT, |
202 | }; |
203 | |
204 | enum sctp_plpmtud_state { |
205 | SCTP_PL_DISABLED, |
206 | SCTP_PL_BASE, |
207 | SCTP_PL_SEARCH, |
208 | SCTP_PL_COMPLETE, |
209 | SCTP_PL_ERROR, |
210 | }; |
211 | |
212 | #define SCTP_BASE_PLPMTU 1200 |
213 | #define SCTP_MAX_PLPMTU 9000 |
214 | #define SCTP_MIN_PLPMTU 512 |
215 | |
216 | #define SCTP_MAX_PROBES 3 |
217 | |
218 | #define SCTP_PL_BIG_STEP 32 |
219 | #define SCTP_PL_MIN_STEP 4 |
220 | |
221 | /* These functions map various type to printable names. */ |
222 | const char *sctp_cname(const union sctp_subtype id); /* chunk types */ |
223 | const char *sctp_oname(const union sctp_subtype id); /* other events */ |
224 | const char *sctp_tname(const union sctp_subtype id); /* timeouts */ |
225 | const char *sctp_pname(const union sctp_subtype id); /* 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 512. Remove all the headers and there |
256 | * is enough room for 117 duplicate reports. Round down to the |
257 | * nearest power of 2. |
258 | */ |
259 | enum { SCTP_MAX_DUP_TSNS = 16 }; |
260 | enum { SCTP_MAX_GABS = 16 }; |
261 | |
262 | /* Heartbeat interval - 30 secs */ |
263 | #define SCTP_DEFAULT_TIMEOUT_HEARTBEAT (30*1000) |
264 | |
265 | /* Delayed sack timer - 200ms */ |
266 | #define SCTP_DEFAULT_TIMEOUT_SACK (200) |
267 | |
268 | /* RTO.Initial - 3 seconds |
269 | * RTO.Min - 1 second |
270 | * RTO.Max - 60 seconds |
271 | * RTO.Alpha - 1/8 |
272 | * RTO.Beta - 1/4 |
273 | */ |
274 | #define SCTP_RTO_INITIAL (3 * 1000) |
275 | #define SCTP_RTO_MIN (1 * 1000) |
276 | #define SCTP_RTO_MAX (60 * 1000) |
277 | |
278 | #define SCTP_RTO_ALPHA 3 /* 1/8 when converted to right shifts. */ |
279 | #define SCTP_RTO_BETA 2 /* 1/4 when converted to right shifts. */ |
280 | |
281 | /* Maximum number of new data packets that can be sent in a burst. */ |
282 | #define SCTP_DEFAULT_MAX_BURST 4 |
283 | |
284 | #define SCTP_CLOCK_GRANULARITY 1 /* 1 jiffy */ |
285 | |
286 | #define SCTP_DEFAULT_COOKIE_LIFE (60 * 1000) /* 60 seconds */ |
287 | |
288 | #define SCTP_DEFAULT_MINWINDOW 1500 /* default minimum rwnd size */ |
289 | #define SCTP_DEFAULT_MAXWINDOW 65535 /* default rwnd size */ |
290 | #define SCTP_DEFAULT_RWND_SHIFT 4 /* by default, update on 1/16 of |
291 | * rcvbuf, which is 1/8 of initial |
292 | * window |
293 | */ |
294 | #define SCTP_DEFAULT_MAXSEGMENT 1500 /* MTU size, this is the limit |
295 | * to which we will raise the P-MTU. |
296 | */ |
297 | #define SCTP_DEFAULT_MINSEGMENT 512 /* MTU size ... if no mtu disc */ |
298 | |
299 | #define SCTP_SECRET_SIZE 32 /* Number of octets in a 256 bits. */ |
300 | |
301 | #define SCTP_SIGNATURE_SIZE 20 /* size of a SLA-1 signature */ |
302 | |
303 | #define SCTP_COOKIE_MULTIPLE 32 /* Pad out our cookie to make our hash |
304 | * functions simpler to write. |
305 | */ |
306 | |
307 | #define SCTP_DEFAULT_UDP_PORT 9899 /* default UDP tunneling port */ |
308 | |
309 | /* These are the values for pf exposure, UNUSED is to keep compatible with old |
310 | * applications by default. |
311 | */ |
312 | enum { |
313 | SCTP_PF_EXPOSE_UNSET, |
314 | SCTP_PF_EXPOSE_DISABLE, |
315 | SCTP_PF_EXPOSE_ENABLE, |
316 | }; |
317 | #define SCTP_PF_EXPOSE_MAX SCTP_PF_EXPOSE_ENABLE |
318 | |
319 | #define SCTP_PS_RETRANS_MAX 0xffff |
320 | |
321 | /* These return values describe the success or failure of a number of |
322 | * routines which form the lower interface to SCTP_outqueue. |
323 | */ |
324 | enum sctp_xmit { |
325 | SCTP_XMIT_OK, |
326 | SCTP_XMIT_PMTU_FULL, |
327 | SCTP_XMIT_RWND_FULL, |
328 | SCTP_XMIT_DELAY, |
329 | }; |
330 | |
331 | /* These are the commands for manipulating transports. */ |
332 | enum sctp_transport_cmd { |
333 | SCTP_TRANSPORT_UP, |
334 | SCTP_TRANSPORT_DOWN, |
335 | SCTP_TRANSPORT_PF, |
336 | }; |
337 | |
338 | /* These are the address scopes defined mainly for IPv4 addresses |
339 | * based on draft of SCTP IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>. |
340 | * These scopes are hopefully generic enough to be used on scoping both |
341 | * IPv4 and IPv6 addresses in SCTP. |
342 | * At this point, the IPv6 scopes will be mapped to these internal scopes |
343 | * as much as possible. |
344 | */ |
345 | enum sctp_scope { |
346 | SCTP_SCOPE_GLOBAL, /* IPv4 global addresses */ |
347 | SCTP_SCOPE_PRIVATE, /* IPv4 private addresses */ |
348 | SCTP_SCOPE_LINK, /* IPv4 link local address */ |
349 | SCTP_SCOPE_LOOPBACK, /* IPv4 loopback address */ |
350 | SCTP_SCOPE_UNUSABLE, /* IPv4 unusable addresses */ |
351 | }; |
352 | |
353 | enum { |
354 | SCTP_SCOPE_POLICY_DISABLE, /* Disable IPv4 address scoping */ |
355 | SCTP_SCOPE_POLICY_ENABLE, /* Enable IPv4 address scoping */ |
356 | SCTP_SCOPE_POLICY_PRIVATE, /* Follow draft but allow IPv4 private addresses */ |
357 | SCTP_SCOPE_POLICY_LINK, /* Follow draft but allow IPv4 link local addresses */ |
358 | }; |
359 | |
360 | #define SCTP_SCOPE_POLICY_MAX SCTP_SCOPE_POLICY_LINK |
361 | |
362 | /* Based on IPv4 scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>, |
363 | * SCTP IPv4 unusable addresses: 0.0.0.0/8, 224.0.0.0/4, 192.88.99.0/24. |
364 | * Also, RFC 8.4, non-unicast addresses are not considered valid SCTP |
365 | * addresses. |
366 | */ |
367 | #define IS_IPV4_UNUSABLE_ADDRESS(a) \ |
368 | ((htonl(INADDR_BROADCAST) == a) || \ |
369 | ipv4_is_multicast(a) || \ |
370 | ipv4_is_zeronet(a) || \ |
371 | ipv4_is_anycast_6to4(a)) |
372 | |
373 | /* Flags used for the bind address copy functions. */ |
374 | #define SCTP_ADDR4_ALLOWED 0x00000001 /* IPv4 address is allowed by |
375 | local sock family */ |
376 | #define SCTP_ADDR6_ALLOWED 0x00000002 /* IPv6 address is allowed by |
377 | local sock family */ |
378 | #define SCTP_ADDR4_PEERSUPP 0x00000004 /* IPv4 address is supported by |
379 | peer */ |
380 | #define SCTP_ADDR6_PEERSUPP 0x00000008 /* IPv6 address is supported by |
381 | peer */ |
382 | |
383 | /* Reasons to retransmit. */ |
384 | enum sctp_retransmit_reason { |
385 | SCTP_RTXR_T3_RTX, |
386 | SCTP_RTXR_FAST_RTX, |
387 | SCTP_RTXR_PMTUD, |
388 | SCTP_RTXR_T1_RTX, |
389 | }; |
390 | |
391 | /* Reasons to lower cwnd. */ |
392 | enum sctp_lower_cwnd { |
393 | SCTP_LOWER_CWND_T3_RTX, |
394 | SCTP_LOWER_CWND_FAST_RTX, |
395 | SCTP_LOWER_CWND_ECNE, |
396 | SCTP_LOWER_CWND_INACTIVE, |
397 | }; |
398 | |
399 | |
400 | /* SCTP-AUTH Necessary constants */ |
401 | |
402 | /* SCTP-AUTH, Section 3.3 |
403 | * |
404 | * The following Table 2 shows the currently defined values for HMAC |
405 | * identifiers. |
406 | * |
407 | * +-----------------+--------------------------+ |
408 | * | HMAC Identifier | Message Digest Algorithm | |
409 | * +-----------------+--------------------------+ |
410 | * | 0 | Reserved | |
411 | * | 1 | SHA-1 defined in [8] | |
412 | * | 2 | Reserved | |
413 | * | 3 | SHA-256 defined in [8] | |
414 | * +-----------------+--------------------------+ |
415 | */ |
416 | enum { |
417 | SCTP_AUTH_HMAC_ID_RESERVED_0, |
418 | SCTP_AUTH_HMAC_ID_SHA1, |
419 | SCTP_AUTH_HMAC_ID_RESERVED_2, |
420 | #if defined (CONFIG_CRYPTO_SHA256) || defined (CONFIG_CRYPTO_SHA256_MODULE) |
421 | SCTP_AUTH_HMAC_ID_SHA256, |
422 | #endif |
423 | __SCTP_AUTH_HMAC_MAX |
424 | }; |
425 | |
426 | #define SCTP_AUTH_HMAC_ID_MAX __SCTP_AUTH_HMAC_MAX - 1 |
427 | #define SCTP_AUTH_NUM_HMACS __SCTP_AUTH_HMAC_MAX |
428 | #define SCTP_SHA1_SIG_SIZE 20 |
429 | #define SCTP_SHA256_SIG_SIZE 32 |
430 | |
431 | /* SCTP-AUTH, Section 3.2 |
432 | * The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH chunks |
433 | * MUST NOT be listed in the CHUNKS parameter |
434 | */ |
435 | #define SCTP_NUM_NOAUTH_CHUNKS 4 |
436 | #define SCTP_AUTH_MAX_CHUNKS (SCTP_NUM_CHUNK_TYPES - SCTP_NUM_NOAUTH_CHUNKS) |
437 | |
438 | /* SCTP-AUTH Section 6.1 |
439 | * The RANDOM parameter MUST contain a 32 byte random number. |
440 | */ |
441 | #define SCTP_AUTH_RANDOM_LENGTH 32 |
442 | |
443 | #define SCTP_PROBE_TIMER_MIN 5000 |
444 | |
445 | #endif /* __sctp_constants_h__ */ |
446 | |