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) 2001-2003 Intel Corp.
7 * This file is part of the SCTP kernel implementation
9 * The base lksctp header.
11 * This SCTP implementation is free software;
12 * you can redistribute it and/or modify it under the terms of
13 * the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
17 * This SCTP implementation is distributed in the hope that it
18 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
19 * ************************
20 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
21 * See the GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with GNU CC; see the file COPYING. If not, see
25 * <http://www.gnu.org/licenses/>.
27 * Please send any bug reports or fixes you make to the
29 * lksctp developers <linux-sctp@vger.kernel.org>
31 * Written or modified by:
32 * La Monte H.P. Yarroll <piggy@acm.org>
33 * Xingang Guo <xingang.guo@intel.com>
34 * Jon Grimm <jgrimm@us.ibm.com>
35 * Daisy Chang <daisyc@us.ibm.com>
36 * Sridhar Samudrala <sri@us.ibm.com>
37 * Ardelle Fan <ardelle.fan@intel.com>
38 * Ryan Layer <rmlayer@us.ibm.com>
39 * Kevin Gao <kevin.gao@intel.com>
42 #ifndef __net_sctp_h__
43 #define __net_sctp_h__
46 * Start getting some control over the header file depencies:
51 * macros, externs, and inlines
53 * Move test_frame specific items out of the kernel headers
54 * and into the test frame headers. This is not perfect in any sense
55 * and will continue to evolve.
58 #include <linux/types.h>
59 #include <linux/slab.h>
61 #include <linux/tty.h>
62 #include <linux/proc_fs.h>
63 #include <linux/spinlock.h>
64 #include <linux/jiffies.h>
65 #include <linux/idr.h>
67 #if IS_ENABLED(CONFIG_IPV6)
69 #include <net/ip6_route.h>
72 #include <asm/uaccess.h>
76 #include <net/sctp/structs.h>
77 #include <net/sctp/constants.h>
79 #ifdef CONFIG_IP_SCTP_MODULE
80 #define SCTP_PROTOSW_FLAG 0
82 #define SCTP_PROTOSW_FLAG INET_PROTOSW_PERMANENT
86 * Function declarations.
92 int sctp_copy_local_addr_list(struct net *, struct sctp_bind_addr *,
93 sctp_scope_t, gfp_t gfp, int flags);
94 struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
95 int sctp_register_pf(struct sctp_pf *, sa_family_t);
96 void sctp_addr_wq_mgmt(struct net *, struct sctp_sockaddr_entry *, int);
101 int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
102 int sctp_inet_listen(struct socket *sock, int backlog);
103 void sctp_write_space(struct sock *sk);
104 void sctp_data_ready(struct sock *sk, int len);
105 unsigned int sctp_poll(struct file *file, struct socket *sock,
107 void sctp_sock_rfree(struct sk_buff *skb);
108 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
109 struct sctp_association *asoc);
110 extern struct percpu_counter sctp_sockets_allocated;
111 int sctp_asconf_mgmt(struct sctp_sock *, struct sctp_sockaddr_entry *);
116 int sctp_primitive_ASSOCIATE(struct net *, struct sctp_association *, void *arg);
117 int sctp_primitive_SHUTDOWN(struct net *, struct sctp_association *, void *arg);
118 int sctp_primitive_ABORT(struct net *, struct sctp_association *, void *arg);
119 int sctp_primitive_SEND(struct net *, struct sctp_association *, void *arg);
120 int sctp_primitive_REQUESTHEARTBEAT(struct net *, struct sctp_association *, void *arg);
121 int sctp_primitive_ASCONF(struct net *, struct sctp_association *, void *arg);
126 int sctp_rcv(struct sk_buff *skb);
127 void sctp_v4_err(struct sk_buff *skb, u32 info);
128 void sctp_hash_established(struct sctp_association *);
129 void sctp_unhash_established(struct sctp_association *);
130 void sctp_hash_endpoint(struct sctp_endpoint *);
131 void sctp_unhash_endpoint(struct sctp_endpoint *);
132 struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *,
133 struct sctphdr *, struct sctp_association **,
134 struct sctp_transport **);
135 void sctp_err_finish(struct sock *, struct sctp_association *);
136 void sctp_icmp_frag_needed(struct sock *, struct sctp_association *,
137 struct sctp_transport *t, __u32 pmtu);
138 void sctp_icmp_redirect(struct sock *, struct sctp_transport *,
140 void sctp_icmp_proto_unreachable(struct sock *sk,
141 struct sctp_association *asoc,
142 struct sctp_transport *t);
143 void sctp_backlog_migrate(struct sctp_association *assoc,
144 struct sock *oldsk, struct sock *newsk);
149 int sctp_snmp_proc_init(struct net *net);
150 void sctp_snmp_proc_exit(struct net *net);
151 int sctp_eps_proc_init(struct net *net);
152 void sctp_eps_proc_exit(struct net *net);
153 int sctp_assocs_proc_init(struct net *net);
154 void sctp_assocs_proc_exit(struct net *net);
155 int sctp_remaddr_proc_init(struct net *net);
156 void sctp_remaddr_proc_exit(struct net *net);
160 * Module global variables
166 extern struct kmem_cache *sctp_chunk_cachep __read_mostly;
167 extern struct kmem_cache *sctp_bucket_cachep __read_mostly;
170 * Section: Macros, externs, and inlines
173 /* spin lock wrappers. */
174 #define sctp_spin_lock(lock) spin_lock(lock)
175 #define sctp_spin_unlock(lock) spin_unlock(lock)
176 #define sctp_write_lock(lock) write_lock(lock)
177 #define sctp_write_unlock(lock) write_unlock(lock)
178 #define sctp_read_lock(lock) read_lock(lock)
179 #define sctp_read_unlock(lock) read_unlock(lock)
181 /* sock lock wrappers. */
182 #define sctp_lock_sock(sk) lock_sock(sk)
183 #define sctp_release_sock(sk) release_sock(sk)
184 #define sctp_bh_lock_sock(sk) bh_lock_sock(sk)
185 #define sctp_bh_unlock_sock(sk) bh_unlock_sock(sk)
187 /* SCTP SNMP MIB stats handlers */
188 #define SCTP_INC_STATS(net, field) SNMP_INC_STATS((net)->sctp.sctp_statistics, field)
189 #define SCTP_INC_STATS_BH(net, field) SNMP_INC_STATS_BH((net)->sctp.sctp_statistics, field)
190 #define SCTP_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)->sctp.sctp_statistics, field)
191 #define SCTP_DEC_STATS(net, field) SNMP_DEC_STATS((net)->sctp.sctp_statistics, field)
193 /* sctp mib definitions */
196 SCTP_MIB_CURRESTAB, /* CurrEstab */
197 SCTP_MIB_ACTIVEESTABS, /* ActiveEstabs */
198 SCTP_MIB_PASSIVEESTABS, /* PassiveEstabs */
199 SCTP_MIB_ABORTEDS, /* Aborteds */
200 SCTP_MIB_SHUTDOWNS, /* Shutdowns */
201 SCTP_MIB_OUTOFBLUES, /* OutOfBlues */
202 SCTP_MIB_CHECKSUMERRORS, /* ChecksumErrors */
203 SCTP_MIB_OUTCTRLCHUNKS, /* OutCtrlChunks */
204 SCTP_MIB_OUTORDERCHUNKS, /* OutOrderChunks */
205 SCTP_MIB_OUTUNORDERCHUNKS, /* OutUnorderChunks */
206 SCTP_MIB_INCTRLCHUNKS, /* InCtrlChunks */
207 SCTP_MIB_INORDERCHUNKS, /* InOrderChunks */
208 SCTP_MIB_INUNORDERCHUNKS, /* InUnorderChunks */
209 SCTP_MIB_FRAGUSRMSGS, /* FragUsrMsgs */
210 SCTP_MIB_REASMUSRMSGS, /* ReasmUsrMsgs */
211 SCTP_MIB_OUTSCTPPACKS, /* OutSCTPPacks */
212 SCTP_MIB_INSCTPPACKS, /* InSCTPPacks */
213 SCTP_MIB_T1_INIT_EXPIREDS,
214 SCTP_MIB_T1_COOKIE_EXPIREDS,
215 SCTP_MIB_T2_SHUTDOWN_EXPIREDS,
216 SCTP_MIB_T3_RTX_EXPIREDS,
217 SCTP_MIB_T4_RTO_EXPIREDS,
218 SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS,
219 SCTP_MIB_DELAY_SACK_EXPIREDS,
220 SCTP_MIB_AUTOCLOSE_EXPIREDS,
221 SCTP_MIB_T1_RETRANSMITS,
222 SCTP_MIB_T3_RETRANSMITS,
223 SCTP_MIB_PMTUD_RETRANSMITS,
224 SCTP_MIB_FAST_RETRANSMITS,
225 SCTP_MIB_IN_PKT_SOFTIRQ,
226 SCTP_MIB_IN_PKT_BACKLOG,
227 SCTP_MIB_IN_PKT_DISCARDS,
228 SCTP_MIB_IN_DATA_CHUNK_DISCARDS,
232 #define SCTP_MIB_MAX __SCTP_MIB_MAX
234 unsigned long mibs[SCTP_MIB_MAX];
237 /* helper function to track stats about max rto and related transport */
238 static inline void sctp_max_rto(struct sctp_association *asoc,
239 struct sctp_transport *trans)
241 if (asoc->stats.max_obs_rto < (__u64)trans->rto) {
242 asoc->stats.max_obs_rto = trans->rto;
243 memset(&asoc->stats.obs_rto_ipaddr, 0,
244 sizeof(struct sockaddr_storage));
245 memcpy(&asoc->stats.obs_rto_ipaddr, &trans->ipaddr,
246 trans->af_specific->sockaddr_len);
251 * Macros for keeping a global reference of object allocations.
253 #ifdef CONFIG_SCTP_DBG_OBJCNT
255 extern atomic_t sctp_dbg_objcnt_sock;
256 extern atomic_t sctp_dbg_objcnt_ep;
257 extern atomic_t sctp_dbg_objcnt_assoc;
258 extern atomic_t sctp_dbg_objcnt_transport;
259 extern atomic_t sctp_dbg_objcnt_chunk;
260 extern atomic_t sctp_dbg_objcnt_bind_addr;
261 extern atomic_t sctp_dbg_objcnt_bind_bucket;
262 extern atomic_t sctp_dbg_objcnt_addr;
263 extern atomic_t sctp_dbg_objcnt_ssnmap;
264 extern atomic_t sctp_dbg_objcnt_datamsg;
265 extern atomic_t sctp_dbg_objcnt_keys;
267 /* Macros to atomically increment/decrement objcnt counters. */
268 #define SCTP_DBG_OBJCNT_INC(name) \
269 atomic_inc(&sctp_dbg_objcnt_## name)
270 #define SCTP_DBG_OBJCNT_DEC(name) \
271 atomic_dec(&sctp_dbg_objcnt_## name)
272 #define SCTP_DBG_OBJCNT(name) \
273 atomic_t sctp_dbg_objcnt_## name = ATOMIC_INIT(0)
275 /* Macro to help create new entries in in the global array of
278 #define SCTP_DBG_OBJCNT_ENTRY(name) \
279 {.label= #name, .counter= &sctp_dbg_objcnt_## name}
281 void sctp_dbg_objcnt_init(struct net *);
282 void sctp_dbg_objcnt_exit(struct net *);
286 #define SCTP_DBG_OBJCNT_INC(name)
287 #define SCTP_DBG_OBJCNT_DEC(name)
289 static inline void sctp_dbg_objcnt_init(struct net *net) { return; }
290 static inline void sctp_dbg_objcnt_exit(struct net *net) { return; }
292 #endif /* CONFIG_SCTP_DBG_OBJCOUNT */
294 #if defined CONFIG_SYSCTL
295 void sctp_sysctl_register(void);
296 void sctp_sysctl_unregister(void);
297 int sctp_sysctl_net_register(struct net *net);
298 void sctp_sysctl_net_unregister(struct net *net);
300 static inline void sctp_sysctl_register(void) { return; }
301 static inline void sctp_sysctl_unregister(void) { return; }
302 static inline int sctp_sysctl_net_register(struct net *net) { return 0; }
303 static inline void sctp_sysctl_net_unregister(struct net *net) { return; }
306 /* Size of Supported Address Parameter for 'x' address types. */
307 #define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16))
309 #if IS_ENABLED(CONFIG_IPV6)
311 void sctp_v6_pf_init(void);
312 void sctp_v6_pf_exit(void);
313 int sctp_v6_protosw_init(void);
314 void sctp_v6_protosw_exit(void);
315 int sctp_v6_add_protocol(void);
316 void sctp_v6_del_protocol(void);
318 #else /* #ifdef defined(CONFIG_IPV6) */
320 static inline void sctp_v6_pf_init(void) { return; }
321 static inline void sctp_v6_pf_exit(void) { return; }
322 static inline int sctp_v6_protosw_init(void) { return 0; }
323 static inline void sctp_v6_protosw_exit(void) { return; }
324 static inline int sctp_v6_add_protocol(void) { return 0; }
325 static inline void sctp_v6_del_protocol(void) { return; }
327 #endif /* #if defined(CONFIG_IPV6) */
330 /* Map an association to an assoc_id. */
331 static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc)
333 return asoc ? asoc->assoc_id : 0;
336 /* Look up the association by its id. */
337 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);
339 int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp);
341 /* A macro to walk a list of skbs. */
342 #define sctp_skb_for_each(pos, head, tmp) \
343 skb_queue_walk_safe(head, pos, tmp)
345 /* A helper to append an entire skb list (list) to another (head). */
346 static inline void sctp_skb_list_tail(struct sk_buff_head *list,
347 struct sk_buff_head *head)
351 spin_lock_irqsave(&head->lock, flags);
352 sctp_spin_lock(&list->lock);
354 skb_queue_splice_tail_init(list, head);
356 sctp_spin_unlock(&list->lock);
357 spin_unlock_irqrestore(&head->lock, flags);
361 * sctp_list_dequeue - remove from the head of the queue
362 * @list: list to dequeue from
364 * Remove the head of the list. The head item is
365 * returned or %NULL if the list is empty.
368 static inline struct list_head *sctp_list_dequeue(struct list_head *list)
370 struct list_head *result = NULL;
372 if (list->next != list) {
374 list->next = result->next;
375 list->next->prev = list;
376 INIT_LIST_HEAD(result);
381 /* SCTP version of skb_set_owner_r. We need this one because
382 * of the way we have to do receive buffer accounting on bundled
385 static inline void sctp_skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
387 struct sctp_ulpevent *event = sctp_skb2event(skb);
391 skb->destructor = sctp_sock_rfree;
392 atomic_add(event->rmem_len, &sk->sk_rmem_alloc);
394 * This mimics the behavior of skb_set_owner_r
396 sk->sk_forward_alloc -= event->rmem_len;
399 /* Tests if the list has one and only one entry. */
400 static inline int sctp_list_single_entry(struct list_head *head)
402 return (head->next != head) && (head->next == head->prev);
405 /* Generate a random jitter in the range of -50% ~ +50% of input RTO. */
406 static inline __s32 sctp_jitter(__u32 rto)
408 static __u32 sctp_rand;
411 /* Avoid divide by zero. */
415 sctp_rand += jiffies;
416 sctp_rand ^= (sctp_rand << 12);
417 sctp_rand ^= (sctp_rand >> 20);
419 /* Choose random number from 0 to rto, then move to -50% ~ +50%
422 ret = sctp_rand % rto - (rto >> 1);
426 /* Break down data chunks at this point. */
427 static inline int sctp_frag_point(const struct sctp_association *asoc, int pmtu)
429 struct sctp_sock *sp = sctp_sk(asoc->base.sk);
432 frag -= sp->pf->af->net_header_len;
433 frag -= sizeof(struct sctphdr) + sizeof(struct sctp_data_chunk);
436 frag = min_t(int, frag, asoc->user_frag);
438 frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN);
443 static inline void sctp_assoc_pending_pmtu(struct sock *sk, struct sctp_association *asoc)
446 sctp_assoc_sync_pmtu(sk, asoc);
447 asoc->pmtu_pending = 0;
450 /* Walk through a list of TLV parameters. Don't trust the
451 * individual parameter lengths and instead depend on
452 * the chunk length to indicate when to stop. Make sure
453 * there is room for a param header too.
455 #define sctp_walk_params(pos, chunk, member)\
456 _sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length), member)
458 #define _sctp_walk_params(pos, chunk, end, member)\
459 for (pos.v = chunk->member;\
460 pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\
461 ntohs(pos.p->length) >= sizeof(sctp_paramhdr_t);\
462 pos.v += WORD_ROUND(ntohs(pos.p->length)))
464 #define sctp_walk_errors(err, chunk_hdr)\
465 _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
467 #define _sctp_walk_errors(err, chunk_hdr, end)\
468 for (err = (sctp_errhdr_t *)((void *)chunk_hdr + \
469 sizeof(sctp_chunkhdr_t));\
470 (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\
471 ntohs(err->length) >= sizeof(sctp_errhdr_t); \
472 err = (sctp_errhdr_t *)((void *)err + WORD_ROUND(ntohs(err->length))))
474 #define sctp_walk_fwdtsn(pos, chunk)\
475 _sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk))
477 #define _sctp_walk_fwdtsn(pos, chunk, end)\
478 for (pos = chunk->subh.fwdtsn_hdr->skip;\
479 (void *)pos <= (void *)chunk->subh.fwdtsn_hdr->skip + end - sizeof(struct sctp_fwdtsn_skip);\
482 /* Round an int up to the next multiple of 4. */
483 #define WORD_ROUND(s) (((s)+3)&~3)
485 /* External references. */
487 extern struct proto sctp_prot;
488 extern struct proto sctpv6_prot;
489 void sctp_put_port(struct sock *sk);
491 extern struct idr sctp_assocs_id;
492 extern spinlock_t sctp_assocs_id_lock;
494 /* Static inline functions. */
496 /* Convert from an IP version number to an Address Family symbol. */
497 static inline int ipver2af(__u8 ipver)
509 /* Convert from an address parameter type to an address family. */
510 static inline int param_type2af(__be16 type)
513 case SCTP_PARAM_IPV4_ADDRESS:
515 case SCTP_PARAM_IPV6_ADDRESS:
522 /* Warning: The following hash functions assume a power of two 'size'. */
523 /* This is the hash function for the SCTP port hash table. */
524 static inline int sctp_phashfn(struct net *net, __u16 lport)
526 return (net_hash_mix(net) + lport) & (sctp_port_hashsize - 1);
529 /* This is the hash function for the endpoint hash table. */
530 static inline int sctp_ep_hashfn(struct net *net, __u16 lport)
532 return (net_hash_mix(net) + lport) & (sctp_ep_hashsize - 1);
535 /* This is the hash function for the association hash table. */
536 static inline int sctp_assoc_hashfn(struct net *net, __u16 lport, __u16 rport)
538 int h = (lport << 16) + rport + net_hash_mix(net);
540 return h & (sctp_assoc_hashsize - 1);
543 /* This is the hash function for the association hash table. This is
544 * not used yet, but could be used as a better hash function when
547 static inline int sctp_vtag_hashfn(__u16 lport, __u16 rport, __u32 vtag)
549 int h = (lport << 16) + rport;
551 return h & (sctp_assoc_hashsize - 1);
554 #define sctp_for_each_hentry(epb, head) \
555 hlist_for_each_entry(epb, head, node)
557 /* Is a socket of this style? */
558 #define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
559 static inline int __sctp_style(const struct sock *sk, sctp_socket_type_t style)
561 return sctp_sk(sk)->type == style;
564 /* Is the association in this state? */
565 #define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state))
566 static inline int __sctp_state(const struct sctp_association *asoc,
569 return asoc->state == state;
572 /* Is the socket in this state? */
573 #define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state))
574 static inline int __sctp_sstate(const struct sock *sk, sctp_sock_state_t state)
576 return sk->sk_state == state;
579 /* Map v4-mapped v6 address back to v4 address */
580 static inline void sctp_v6_map_v4(union sctp_addr *addr)
582 addr->v4.sin_family = AF_INET;
583 addr->v4.sin_port = addr->v6.sin6_port;
584 addr->v4.sin_addr.s_addr = addr->v6.sin6_addr.s6_addr32[3];
587 /* Map v4 address to v4-mapped v6 address */
588 static inline void sctp_v4_map_v6(union sctp_addr *addr)
590 addr->v6.sin6_family = AF_INET6;
591 addr->v6.sin6_port = addr->v4.sin_port;
592 addr->v6.sin6_addr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
593 addr->v6.sin6_addr.s6_addr32[0] = 0;
594 addr->v6.sin6_addr.s6_addr32[1] = 0;
595 addr->v6.sin6_addr.s6_addr32[2] = htonl(0x0000ffff);
598 /* The cookie is always 0 since this is how it's used in the
601 static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t)
603 if (t->dst && !dst_check(t->dst, t->dst_cookie)) {
611 #endif /* __net_sctp_h__ */