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.
6 *
7 * This file is part of the SCTP kernel implementation
8 *
9 * The base lksctp header.
10 *
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)
15 * any later version.
16 *
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.
22 *
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/>.
26 *
27 * Please send any bug reports or fixes you make to the
28 * email address(es):
29 * lksctp developers <linux-sctp@vger.kernel.org>
30 *
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>
40 */
41
42 #ifndef __net_sctp_h__
43 #define __net_sctp_h__
44
45 /* Header Strategy.
46 * Start getting some control over the header file depencies:
47 * includes
48 * constants
49 * structs
50 * prototypes
51 * macros, externs, and inlines
52 *
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.
56 */
57
58 #include <linux/types.h>
59 #include <linux/slab.h>
60 #include <linux/in.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>
66
67 #if IS_ENABLED(CONFIG_IPV6)
68 #include <net/ipv6.h>
69 #include <net/ip6_route.h>
70 #endif
71
72 #include <linux/uaccess.h>
73 #include <asm/page.h>
74 #include <net/sock.h>
75 #include <net/snmp.h>
76 #include <net/sctp/structs.h>
77 #include <net/sctp/constants.h>
78
79 #ifdef CONFIG_IP_SCTP_MODULE
80 #define SCTP_PROTOSW_FLAG 0
81 #else /* static! */
82 #define SCTP_PROTOSW_FLAG INET_PROTOSW_PERMANENT
83 #endif
84
85 /* Round an int up to the next multiple of 4. */
86 #define SCTP_PAD4(s) (((s)+3)&~3)
87 /* Truncate to the previous multiple of 4. */
88 #define SCTP_TRUNC4(s) ((s)&~3)
89
90 /*
91 * Function declarations.
92 */
93
94 /*
95 * sctp/protocol.c
96 */
97 int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *addr,
98 enum sctp_scope, gfp_t gfp, int flags);
99 struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
100 int sctp_register_pf(struct sctp_pf *, sa_family_t);
101 void sctp_addr_wq_mgmt(struct net *, struct sctp_sockaddr_entry *, int);
102
103 /*
104 * sctp/socket.c
105 */
106 int sctp_inet_connect(struct socket *sock, struct sockaddr *uaddr,
107 int addr_len, int flags);
108 int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
109 int sctp_inet_listen(struct socket *sock, int backlog);
110 void sctp_write_space(struct sock *sk);
111 void sctp_data_ready(struct sock *sk);
112 __poll_t sctp_poll(struct file *file, struct socket *sock,
113 poll_table *wait);
114 void sctp_sock_rfree(struct sk_buff *skb);
115 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
116 struct sctp_association *asoc);
117 extern struct percpu_counter sctp_sockets_allocated;
118 int sctp_asconf_mgmt(struct sctp_sock *, struct sctp_sockaddr_entry *);
119 struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);
120
121 void sctp_transport_walk_start(struct rhashtable_iter *iter);
122 void sctp_transport_walk_stop(struct rhashtable_iter *iter);
123 struct sctp_transport *sctp_transport_get_next(struct net *net,
124 struct rhashtable_iter *iter);
125 struct sctp_transport *sctp_transport_get_idx(struct net *net,
126 struct rhashtable_iter *iter, int pos);
127 int sctp_transport_lookup_process(int (*cb)(struct sctp_transport *, void *),
128 struct net *net,
129 const union sctp_addr *laddr,
130 const union sctp_addr *paddr, void *p);
131 int sctp_for_each_transport(int (*cb)(struct sctp_transport *, void *),
132 int (*cb_done)(struct sctp_transport *, void *),
133 struct net *net, int *pos, void *p);
134 int sctp_for_each_endpoint(int (*cb)(struct sctp_endpoint *, void *), void *p);
135 int sctp_get_sctp_info(struct sock *sk, struct sctp_association *asoc,
136 struct sctp_info *info);
137
138 /*
139 * sctp/primitive.c
140 */
141 int sctp_primitive_ASSOCIATE(struct net *, struct sctp_association *, void *arg);
142 int sctp_primitive_SHUTDOWN(struct net *, struct sctp_association *, void *arg);
143 int sctp_primitive_ABORT(struct net *, struct sctp_association *, void *arg);
144 int sctp_primitive_SEND(struct net *, struct sctp_association *, void *arg);
145 int sctp_primitive_REQUESTHEARTBEAT(struct net *, struct sctp_association *, void *arg);
146 int sctp_primitive_ASCONF(struct net *, struct sctp_association *, void *arg);
147 int sctp_primitive_RECONF(struct net *net, struct sctp_association *asoc,
148 void *arg);
149
150 /*
151 * sctp/input.c
152 */
153 int sctp_rcv(struct sk_buff *skb);
154 void sctp_v4_err(struct sk_buff *skb, u32 info);
155 void sctp_hash_endpoint(struct sctp_endpoint *);
156 void sctp_unhash_endpoint(struct sctp_endpoint *);
157 struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *,
158 struct sctphdr *, struct sctp_association **,
159 struct sctp_transport **);
160 void sctp_err_finish(struct sock *, struct sctp_transport *);
161 void sctp_icmp_frag_needed(struct sock *, struct sctp_association *,
162 struct sctp_transport *t, __u32 pmtu);
163 void sctp_icmp_redirect(struct sock *, struct sctp_transport *,
164 struct sk_buff *);
165 void sctp_icmp_proto_unreachable(struct sock *sk,
166 struct sctp_association *asoc,
167 struct sctp_transport *t);
168 void sctp_backlog_migrate(struct sctp_association *assoc,
169 struct sock *oldsk, struct sock *newsk);
170 int sctp_transport_hashtable_init(void);
171 void sctp_transport_hashtable_destroy(void);
172 int sctp_hash_transport(struct sctp_transport *t);
173 void sctp_unhash_transport(struct sctp_transport *t);
174 struct sctp_transport *sctp_addrs_lookup_transport(
175 struct net *net,
176 const union sctp_addr *laddr,
177 const union sctp_addr *paddr);
178 struct sctp_transport *sctp_epaddr_lookup_transport(
179 const struct sctp_endpoint *ep,
180 const union sctp_addr *paddr);
181
182 /*
183 * sctp/proc.c
184 */
185 int __net_init sctp_proc_init(struct net *net);
186
187 /*
188 * sctp/offload.c
189 */
190 int sctp_offload_init(void);
191
192 /*
193 * sctp/stream_sched.c
194 */
195 void sctp_sched_ops_init(void);
196
197 /*
198 * sctp/stream.c
199 */
200 int sctp_send_reset_streams(struct sctp_association *asoc,
201 struct sctp_reset_streams *params);
202 int sctp_send_reset_assoc(struct sctp_association *asoc);
203 int sctp_send_add_streams(struct sctp_association *asoc,
204 struct sctp_add_streams *params);
205
206 /*
207 * Module global variables
208 */
209
210 /*
211 * sctp/protocol.c
212 */
213 extern struct kmem_cache *sctp_chunk_cachep __read_mostly;
214 extern struct kmem_cache *sctp_bucket_cachep __read_mostly;
215 extern long sysctl_sctp_mem[3];
216 extern int sysctl_sctp_rmem[3];
217 extern int sysctl_sctp_wmem[3];
218
219 /*
220 * Section: Macros, externs, and inlines
221 */
222
223 /* SCTP SNMP MIB stats handlers */
224 #define SCTP_INC_STATS(net, field) SNMP_INC_STATS((net)->sctp.sctp_statistics, field)
225 #define __SCTP_INC_STATS(net, field) __SNMP_INC_STATS((net)->sctp.sctp_statistics, field)
226 #define SCTP_DEC_STATS(net, field) SNMP_DEC_STATS((net)->sctp.sctp_statistics, field)
227
228 /* sctp mib definitions */
229 enum {
230 SCTP_MIB_NUM = 0,
231 SCTP_MIB_CURRESTAB, /* CurrEstab */
232 SCTP_MIB_ACTIVEESTABS, /* ActiveEstabs */
233 SCTP_MIB_PASSIVEESTABS, /* PassiveEstabs */
234 SCTP_MIB_ABORTEDS, /* Aborteds */
235 SCTP_MIB_SHUTDOWNS, /* Shutdowns */
236 SCTP_MIB_OUTOFBLUES, /* OutOfBlues */
237 SCTP_MIB_CHECKSUMERRORS, /* ChecksumErrors */
238 SCTP_MIB_OUTCTRLCHUNKS, /* OutCtrlChunks */
239 SCTP_MIB_OUTORDERCHUNKS, /* OutOrderChunks */
240 SCTP_MIB_OUTUNORDERCHUNKS, /* OutUnorderChunks */
241 SCTP_MIB_INCTRLCHUNKS, /* InCtrlChunks */
242 SCTP_MIB_INORDERCHUNKS, /* InOrderChunks */
243 SCTP_MIB_INUNORDERCHUNKS, /* InUnorderChunks */
244 SCTP_MIB_FRAGUSRMSGS, /* FragUsrMsgs */
245 SCTP_MIB_REASMUSRMSGS, /* ReasmUsrMsgs */
246 SCTP_MIB_OUTSCTPPACKS, /* OutSCTPPacks */
247 SCTP_MIB_INSCTPPACKS, /* InSCTPPacks */
248 SCTP_MIB_T1_INIT_EXPIREDS,
249 SCTP_MIB_T1_COOKIE_EXPIREDS,
250 SCTP_MIB_T2_SHUTDOWN_EXPIREDS,
251 SCTP_MIB_T3_RTX_EXPIREDS,
252 SCTP_MIB_T4_RTO_EXPIREDS,
253 SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS,
254 SCTP_MIB_DELAY_SACK_EXPIREDS,
255 SCTP_MIB_AUTOCLOSE_EXPIREDS,
256 SCTP_MIB_T1_RETRANSMITS,
257 SCTP_MIB_T3_RETRANSMITS,
258 SCTP_MIB_PMTUD_RETRANSMITS,
259 SCTP_MIB_FAST_RETRANSMITS,
260 SCTP_MIB_IN_PKT_SOFTIRQ,
261 SCTP_MIB_IN_PKT_BACKLOG,
262 SCTP_MIB_IN_PKT_DISCARDS,
263 SCTP_MIB_IN_DATA_CHUNK_DISCARDS,
264 __SCTP_MIB_MAX
265 };
266
267 #define SCTP_MIB_MAX __SCTP_MIB_MAX
268 struct sctp_mib {
269 unsigned long mibs[SCTP_MIB_MAX];
270 };
271
272 /* helper function to track stats about max rto and related transport */
sctp_max_rto(struct sctp_association * asoc,struct sctp_transport * trans)273 static inline void sctp_max_rto(struct sctp_association *asoc,
274 struct sctp_transport *trans)
275 {
276 if (asoc->stats.max_obs_rto < (__u64)trans->rto) {
277 asoc->stats.max_obs_rto = trans->rto;
278 memset(&asoc->stats.obs_rto_ipaddr, 0,
279 sizeof(struct sockaddr_storage));
280 memcpy(&asoc->stats.obs_rto_ipaddr, &trans->ipaddr,
281 trans->af_specific->sockaddr_len);
282 }
283 }
284
285 /*
286 * Macros for keeping a global reference of object allocations.
287 */
288 #ifdef CONFIG_SCTP_DBG_OBJCNT
289
290 extern atomic_t sctp_dbg_objcnt_sock;
291 extern atomic_t sctp_dbg_objcnt_ep;
292 extern atomic_t sctp_dbg_objcnt_assoc;
293 extern atomic_t sctp_dbg_objcnt_transport;
294 extern atomic_t sctp_dbg_objcnt_chunk;
295 extern atomic_t sctp_dbg_objcnt_bind_addr;
296 extern atomic_t sctp_dbg_objcnt_bind_bucket;
297 extern atomic_t sctp_dbg_objcnt_addr;
298 extern atomic_t sctp_dbg_objcnt_datamsg;
299 extern atomic_t sctp_dbg_objcnt_keys;
300
301 /* Macros to atomically increment/decrement objcnt counters. */
302 #define SCTP_DBG_OBJCNT_INC(name) \
303 atomic_inc(&sctp_dbg_objcnt_## name)
304 #define SCTP_DBG_OBJCNT_DEC(name) \
305 atomic_dec(&sctp_dbg_objcnt_## name)
306 #define SCTP_DBG_OBJCNT(name) \
307 atomic_t sctp_dbg_objcnt_## name = ATOMIC_INIT(0)
308
309 /* Macro to help create new entries in in the global array of
310 * objcnt counters.
311 */
312 #define SCTP_DBG_OBJCNT_ENTRY(name) \
313 {.label= #name, .counter= &sctp_dbg_objcnt_## name}
314
315 void sctp_dbg_objcnt_init(struct net *);
316
317 #else
318
319 #define SCTP_DBG_OBJCNT_INC(name)
320 #define SCTP_DBG_OBJCNT_DEC(name)
321
sctp_dbg_objcnt_init(struct net * net)322 static inline void sctp_dbg_objcnt_init(struct net *net) { return; }
323
324 #endif /* CONFIG_SCTP_DBG_OBJCOUNT */
325
326 #if defined CONFIG_SYSCTL
327 void sctp_sysctl_register(void);
328 void sctp_sysctl_unregister(void);
329 int sctp_sysctl_net_register(struct net *net);
330 void sctp_sysctl_net_unregister(struct net *net);
331 #else
sctp_sysctl_register(void)332 static inline void sctp_sysctl_register(void) { return; }
sctp_sysctl_unregister(void)333 static inline void sctp_sysctl_unregister(void) { return; }
sctp_sysctl_net_register(struct net * net)334 static inline int sctp_sysctl_net_register(struct net *net) { return 0; }
sctp_sysctl_net_unregister(struct net * net)335 static inline void sctp_sysctl_net_unregister(struct net *net) { return; }
336 #endif
337
338 /* Size of Supported Address Parameter for 'x' address types. */
339 #define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16))
340
341 #if IS_ENABLED(CONFIG_IPV6)
342
343 void sctp_v6_pf_init(void);
344 void sctp_v6_pf_exit(void);
345 int sctp_v6_protosw_init(void);
346 void sctp_v6_protosw_exit(void);
347 int sctp_v6_add_protocol(void);
348 void sctp_v6_del_protocol(void);
349
350 #else /* #ifdef defined(CONFIG_IPV6) */
351
sctp_v6_pf_init(void)352 static inline void sctp_v6_pf_init(void) { return; }
sctp_v6_pf_exit(void)353 static inline void sctp_v6_pf_exit(void) { return; }
sctp_v6_protosw_init(void)354 static inline int sctp_v6_protosw_init(void) { return 0; }
sctp_v6_protosw_exit(void)355 static inline void sctp_v6_protosw_exit(void) { return; }
sctp_v6_add_protocol(void)356 static inline int sctp_v6_add_protocol(void) { return 0; }
sctp_v6_del_protocol(void)357 static inline void sctp_v6_del_protocol(void) { return; }
358
359 #endif /* #if defined(CONFIG_IPV6) */
360
361
362 /* Map an association to an assoc_id. */
sctp_assoc2id(const struct sctp_association * asoc)363 static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc)
364 {
365 return asoc ? asoc->assoc_id : 0;
366 }
367
368 static inline enum sctp_sstat_state
sctp_assoc_to_state(const struct sctp_association * asoc)369 sctp_assoc_to_state(const struct sctp_association *asoc)
370 {
371 /* SCTP's uapi always had SCTP_EMPTY(=0) as a dummy state, but we
372 * got rid of it in kernel space. Therefore SCTP_CLOSED et al
373 * start at =1 in user space, but actually as =0 in kernel space.
374 * Now that we can not break user space and SCTP_EMPTY is exposed
375 * there, we need to fix it up with an ugly offset not to break
376 * applications. :(
377 */
378 return asoc->state + 1;
379 }
380
381 /* Look up the association by its id. */
382 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);
383
384 int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp);
385
386 /* A macro to walk a list of skbs. */
387 #define sctp_skb_for_each(pos, head, tmp) \
388 skb_queue_walk_safe(head, pos, tmp)
389
390 /**
391 * sctp_list_dequeue - remove from the head of the queue
392 * @list: list to dequeue from
393 *
394 * Remove the head of the list. The head item is
395 * returned or %NULL if the list is empty.
396 */
397
sctp_list_dequeue(struct list_head * list)398 static inline struct list_head *sctp_list_dequeue(struct list_head *list)
399 {
400 struct list_head *result = NULL;
401
402 if (!list_empty(list)) {
403 result = list->next;
404 list_del_init(result);
405 }
406 return result;
407 }
408
409 /* SCTP version of skb_set_owner_r. We need this one because
410 * of the way we have to do receive buffer accounting on bundled
411 * chunks.
412 */
sctp_skb_set_owner_r(struct sk_buff * skb,struct sock * sk)413 static inline void sctp_skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
414 {
415 struct sctp_ulpevent *event = sctp_skb2event(skb);
416
417 skb_orphan(skb);
418 skb->sk = sk;
419 skb->destructor = sctp_sock_rfree;
420 atomic_add(event->rmem_len, &sk->sk_rmem_alloc);
421 /*
422 * This mimics the behavior of skb_set_owner_r
423 */
424 sk->sk_forward_alloc -= event->rmem_len;
425 }
426
427 /* Tests if the list has one and only one entry. */
sctp_list_single_entry(struct list_head * head)428 static inline int sctp_list_single_entry(struct list_head *head)
429 {
430 return (head->next != head) && (head->next == head->prev);
431 }
432
sctp_chunk_pending(const struct sctp_chunk * chunk)433 static inline bool sctp_chunk_pending(const struct sctp_chunk *chunk)
434 {
435 return !list_empty(&chunk->list);
436 }
437
438 /* Walk through a list of TLV parameters. Don't trust the
439 * individual parameter lengths and instead depend on
440 * the chunk length to indicate when to stop. Make sure
441 * there is room for a param header too.
442 */
443 #define sctp_walk_params(pos, chunk, member)\
444 _sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length), member)
445
446 #define _sctp_walk_params(pos, chunk, end, member)\
447 for (pos.v = chunk->member;\
448 (pos.v + offsetof(struct sctp_paramhdr, length) + sizeof(pos.p->length) <=\
449 (void *)chunk + end) &&\
450 pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\
451 ntohs(pos.p->length) >= sizeof(struct sctp_paramhdr);\
452 pos.v += SCTP_PAD4(ntohs(pos.p->length)))
453
454 #define sctp_walk_errors(err, chunk_hdr)\
455 _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
456
457 #define _sctp_walk_errors(err, chunk_hdr, end)\
458 for (err = (struct sctp_errhdr *)((void *)chunk_hdr + \
459 sizeof(struct sctp_chunkhdr));\
460 ((void *)err + offsetof(struct sctp_errhdr, length) + sizeof(err->length) <=\
461 (void *)chunk_hdr + end) &&\
462 (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\
463 ntohs(err->length) >= sizeof(struct sctp_errhdr); \
464 err = (struct sctp_errhdr *)((void *)err + SCTP_PAD4(ntohs(err->length))))
465
466 #define sctp_walk_fwdtsn(pos, chunk)\
467 _sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk))
468
469 #define _sctp_walk_fwdtsn(pos, chunk, end)\
470 for (pos = chunk->subh.fwdtsn_hdr->skip;\
471 (void *)pos <= (void *)chunk->subh.fwdtsn_hdr->skip + end - sizeof(struct sctp_fwdtsn_skip);\
472 pos++)
473
474 /* External references. */
475
476 extern struct proto sctp_prot;
477 extern struct proto sctpv6_prot;
478 void sctp_put_port(struct sock *sk);
479
480 extern struct idr sctp_assocs_id;
481 extern spinlock_t sctp_assocs_id_lock;
482
483 /* Static inline functions. */
484
485 /* Convert from an IP version number to an Address Family symbol. */
ipver2af(__u8 ipver)486 static inline int ipver2af(__u8 ipver)
487 {
488 switch (ipver) {
489 case 4:
490 return AF_INET;
491 case 6:
492 return AF_INET6;
493 default:
494 return 0;
495 }
496 }
497
498 /* Convert from an address parameter type to an address family. */
param_type2af(__be16 type)499 static inline int param_type2af(__be16 type)
500 {
501 switch (type) {
502 case SCTP_PARAM_IPV4_ADDRESS:
503 return AF_INET;
504 case SCTP_PARAM_IPV6_ADDRESS:
505 return AF_INET6;
506 default:
507 return 0;
508 }
509 }
510
511 /* Warning: The following hash functions assume a power of two 'size'. */
512 /* This is the hash function for the SCTP port hash table. */
sctp_phashfn(struct net * net,__u16 lport)513 static inline int sctp_phashfn(struct net *net, __u16 lport)
514 {
515 return (net_hash_mix(net) + lport) & (sctp_port_hashsize - 1);
516 }
517
518 /* This is the hash function for the endpoint hash table. */
sctp_ep_hashfn(struct net * net,__u16 lport)519 static inline int sctp_ep_hashfn(struct net *net, __u16 lport)
520 {
521 return (net_hash_mix(net) + lport) & (sctp_ep_hashsize - 1);
522 }
523
524 #define sctp_for_each_hentry(epb, head) \
525 hlist_for_each_entry(epb, head, node)
526
527 /* Is a socket of this style? */
528 #define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
__sctp_style(const struct sock * sk,enum sctp_socket_type style)529 static inline int __sctp_style(const struct sock *sk,
530 enum sctp_socket_type style)
531 {
532 return sctp_sk(sk)->type == style;
533 }
534
535 /* Is the association in this state? */
536 #define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state))
__sctp_state(const struct sctp_association * asoc,enum sctp_state state)537 static inline int __sctp_state(const struct sctp_association *asoc,
538 enum sctp_state state)
539 {
540 return asoc->state == state;
541 }
542
543 /* Is the socket in this state? */
544 #define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state))
__sctp_sstate(const struct sock * sk,enum sctp_sock_state state)545 static inline int __sctp_sstate(const struct sock *sk,
546 enum sctp_sock_state state)
547 {
548 return sk->sk_state == state;
549 }
550
551 /* Map v4-mapped v6 address back to v4 address */
sctp_v6_map_v4(union sctp_addr * addr)552 static inline void sctp_v6_map_v4(union sctp_addr *addr)
553 {
554 addr->v4.sin_family = AF_INET;
555 addr->v4.sin_port = addr->v6.sin6_port;
556 addr->v4.sin_addr.s_addr = addr->v6.sin6_addr.s6_addr32[3];
557 }
558
559 /* Map v4 address to v4-mapped v6 address */
sctp_v4_map_v6(union sctp_addr * addr)560 static inline void sctp_v4_map_v6(union sctp_addr *addr)
561 {
562 __be16 port;
563
564 port = addr->v4.sin_port;
565 addr->v6.sin6_addr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
566 addr->v6.sin6_port = port;
567 addr->v6.sin6_family = AF_INET6;
568 addr->v6.sin6_flowinfo = 0;
569 addr->v6.sin6_scope_id = 0;
570 addr->v6.sin6_addr.s6_addr32[0] = 0;
571 addr->v6.sin6_addr.s6_addr32[1] = 0;
572 addr->v6.sin6_addr.s6_addr32[2] = htonl(0x0000ffff);
573 }
574
575 /* The cookie is always 0 since this is how it's used in the
576 * pmtu code.
577 */
sctp_transport_dst_check(struct sctp_transport * t)578 static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t)
579 {
580 if (t->dst && !dst_check(t->dst, t->dst_cookie))
581 sctp_transport_dst_release(t);
582
583 return t->dst;
584 }
585
586 /* Calculate max payload size given a MTU, or the total overhead if
587 * given MTU is zero
588 */
sctp_mtu_payload(const struct sctp_sock * sp,__u32 mtu,__u32 extra)589 static inline __u32 sctp_mtu_payload(const struct sctp_sock *sp,
590 __u32 mtu, __u32 extra)
591 {
592 __u32 overhead = sizeof(struct sctphdr) + extra;
593
594 if (sp)
595 overhead += sp->pf->af->net_header_len;
596 else
597 overhead += sizeof(struct ipv6hdr);
598
599 if (WARN_ON_ONCE(mtu && mtu <= overhead))
600 mtu = overhead;
601
602 return mtu ? mtu - overhead : overhead;
603 }
604
sctp_dst_mtu(const struct dst_entry * dst)605 static inline __u32 sctp_dst_mtu(const struct dst_entry *dst)
606 {
607 return SCTP_TRUNC4(max_t(__u32, dst_mtu(dst),
608 SCTP_DEFAULT_MINSEGMENT));
609 }
610
611 #endif /* __net_sctp_h__ */
612
