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 <linux/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
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)
91 * Function declarations.
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);
106 int sctp_backlog_rcv(struct sock
*sk
, struct sk_buff
*skb
);
107 int sctp_inet_listen(struct socket
*sock
, int backlog
);
108 void sctp_write_space(struct sock
*sk
);
109 void sctp_data_ready(struct sock
*sk
);
110 unsigned int sctp_poll(struct file
*file
, struct socket
*sock
,
112 void sctp_sock_rfree(struct sk_buff
*skb
);
113 void sctp_copy_sock(struct sock
*newsk
, struct sock
*sk
,
114 struct sctp_association
*asoc
);
115 extern struct percpu_counter sctp_sockets_allocated
;
116 int sctp_asconf_mgmt(struct sctp_sock
*, struct sctp_sockaddr_entry
*);
117 struct sk_buff
*sctp_skb_recv_datagram(struct sock
*, int, int, int *);
119 int sctp_transport_walk_start(struct rhashtable_iter
*iter
);
120 void sctp_transport_walk_stop(struct rhashtable_iter
*iter
);
121 struct sctp_transport
*sctp_transport_get_next(struct net
*net
,
122 struct rhashtable_iter
*iter
);
123 struct sctp_transport
*sctp_transport_get_idx(struct net
*net
,
124 struct rhashtable_iter
*iter
, int pos
);
125 int sctp_transport_lookup_process(int (*cb
)(struct sctp_transport
*, void *),
127 const union sctp_addr
*laddr
,
128 const union sctp_addr
*paddr
, void *p
);
129 int sctp_for_each_transport(int (*cb
)(struct sctp_transport
*, void *),
130 int (*cb_done
)(struct sctp_transport
*, void *),
131 struct net
*net
, int *pos
, void *p
);
132 int sctp_for_each_endpoint(int (*cb
)(struct sctp_endpoint
*, void *), void *p
);
133 int sctp_get_sctp_info(struct sock
*sk
, struct sctp_association
*asoc
,
134 struct sctp_info
*info
);
139 int sctp_primitive_ASSOCIATE(struct net
*, struct sctp_association
*, void *arg
);
140 int sctp_primitive_SHUTDOWN(struct net
*, struct sctp_association
*, void *arg
);
141 int sctp_primitive_ABORT(struct net
*, struct sctp_association
*, void *arg
);
142 int sctp_primitive_SEND(struct net
*, struct sctp_association
*, void *arg
);
143 int sctp_primitive_REQUESTHEARTBEAT(struct net
*, struct sctp_association
*, void *arg
);
144 int sctp_primitive_ASCONF(struct net
*, struct sctp_association
*, void *arg
);
145 int sctp_primitive_RECONF(struct net
*net
, struct sctp_association
*asoc
,
151 int sctp_rcv(struct sk_buff
*skb
);
152 void sctp_v4_err(struct sk_buff
*skb
, u32 info
);
153 void sctp_hash_endpoint(struct sctp_endpoint
*);
154 void sctp_unhash_endpoint(struct sctp_endpoint
*);
155 struct sock
*sctp_err_lookup(struct net
*net
, int family
, struct sk_buff
*,
156 struct sctphdr
*, struct sctp_association
**,
157 struct sctp_transport
**);
158 void sctp_err_finish(struct sock
*, struct sctp_transport
*);
159 void sctp_icmp_frag_needed(struct sock
*, struct sctp_association
*,
160 struct sctp_transport
*t
, __u32 pmtu
);
161 void sctp_icmp_redirect(struct sock
*, struct sctp_transport
*,
163 void sctp_icmp_proto_unreachable(struct sock
*sk
,
164 struct sctp_association
*asoc
,
165 struct sctp_transport
*t
);
166 void sctp_backlog_migrate(struct sctp_association
*assoc
,
167 struct sock
*oldsk
, struct sock
*newsk
);
168 int sctp_transport_hashtable_init(void);
169 void sctp_transport_hashtable_destroy(void);
170 int sctp_hash_transport(struct sctp_transport
*t
);
171 void sctp_unhash_transport(struct sctp_transport
*t
);
172 struct sctp_transport
*sctp_addrs_lookup_transport(
174 const union sctp_addr
*laddr
,
175 const union sctp_addr
*paddr
);
176 struct sctp_transport
*sctp_epaddr_lookup_transport(
177 const struct sctp_endpoint
*ep
,
178 const union sctp_addr
*paddr
);
183 int sctp_snmp_proc_init(struct net
*net
);
184 void sctp_snmp_proc_exit(struct net
*net
);
185 int sctp_eps_proc_init(struct net
*net
);
186 void sctp_eps_proc_exit(struct net
*net
);
187 int sctp_assocs_proc_init(struct net
*net
);
188 void sctp_assocs_proc_exit(struct net
*net
);
189 int sctp_remaddr_proc_init(struct net
*net
);
190 void sctp_remaddr_proc_exit(struct net
*net
);
195 int sctp_offload_init(void);
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
);
207 * Module global variables
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];
220 * Section: Macros, externs, and inlines
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)
228 /* sctp mib definitions */
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
,
267 #define SCTP_MIB_MAX __SCTP_MIB_MAX
269 unsigned long mibs
[SCTP_MIB_MAX
];
272 /* helper function to track stats about max rto and related transport */
273 static inline void sctp_max_rto(struct sctp_association
*asoc
,
274 struct sctp_transport
*trans
)
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
);
286 * Macros for keeping a global reference of object allocations.
288 #ifdef CONFIG_SCTP_DBG_OBJCNT
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
;
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)
309 /* Macro to help create new entries in in the global array of
312 #define SCTP_DBG_OBJCNT_ENTRY(name) \
313 {.label= #name, .counter= &sctp_dbg_objcnt_## name}
315 void sctp_dbg_objcnt_init(struct net
*);
316 void sctp_dbg_objcnt_exit(struct net
*);
320 #define SCTP_DBG_OBJCNT_INC(name)
321 #define SCTP_DBG_OBJCNT_DEC(name)
323 static inline void sctp_dbg_objcnt_init(struct net
*net
) { return; }
324 static inline void sctp_dbg_objcnt_exit(struct net
*net
) { return; }
326 #endif /* CONFIG_SCTP_DBG_OBJCOUNT */
328 #if defined CONFIG_SYSCTL
329 void sctp_sysctl_register(void);
330 void sctp_sysctl_unregister(void);
331 int sctp_sysctl_net_register(struct net
*net
);
332 void sctp_sysctl_net_unregister(struct net
*net
);
334 static inline void sctp_sysctl_register(void) { return; }
335 static inline void sctp_sysctl_unregister(void) { return; }
336 static inline int sctp_sysctl_net_register(struct net
*net
) { return 0; }
337 static inline void sctp_sysctl_net_unregister(struct net
*net
) { return; }
340 /* Size of Supported Address Parameter for 'x' address types. */
341 #define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16))
343 #if IS_ENABLED(CONFIG_IPV6)
345 void sctp_v6_pf_init(void);
346 void sctp_v6_pf_exit(void);
347 int sctp_v6_protosw_init(void);
348 void sctp_v6_protosw_exit(void);
349 int sctp_v6_add_protocol(void);
350 void sctp_v6_del_protocol(void);
352 #else /* #ifdef defined(CONFIG_IPV6) */
354 static inline void sctp_v6_pf_init(void) { return; }
355 static inline void sctp_v6_pf_exit(void) { return; }
356 static inline int sctp_v6_protosw_init(void) { return 0; }
357 static inline void sctp_v6_protosw_exit(void) { return; }
358 static inline int sctp_v6_add_protocol(void) { return 0; }
359 static inline void sctp_v6_del_protocol(void) { return; }
361 #endif /* #if defined(CONFIG_IPV6) */
364 /* Map an association to an assoc_id. */
365 static inline sctp_assoc_t
sctp_assoc2id(const struct sctp_association
*asoc
)
367 return asoc
? asoc
->assoc_id
: 0;
370 static inline enum sctp_sstat_state
371 sctp_assoc_to_state(const struct sctp_association
*asoc
)
373 /* SCTP's uapi always had SCTP_EMPTY(=0) as a dummy state, but we
374 * got rid of it in kernel space. Therefore SCTP_CLOSED et al
375 * start at =1 in user space, but actually as =0 in kernel space.
376 * Now that we can not break user space and SCTP_EMPTY is exposed
377 * there, we need to fix it up with an ugly offset not to break
380 return asoc
->state
+ 1;
383 /* Look up the association by its id. */
384 struct sctp_association
*sctp_id2assoc(struct sock
*sk
, sctp_assoc_t id
);
386 int sctp_do_peeloff(struct sock
*sk
, sctp_assoc_t id
, struct socket
**sockp
);
388 /* A macro to walk a list of skbs. */
389 #define sctp_skb_for_each(pos, head, tmp) \
390 skb_queue_walk_safe(head, pos, tmp)
393 * sctp_list_dequeue - remove from the head of the queue
394 * @list: list to dequeue from
396 * Remove the head of the list. The head item is
397 * returned or %NULL if the list is empty.
400 static inline struct list_head
*sctp_list_dequeue(struct list_head
*list
)
402 struct list_head
*result
= NULL
;
404 if (!list_empty(list
)) {
406 list_del_init(result
);
411 /* SCTP version of skb_set_owner_r. We need this one because
412 * of the way we have to do receive buffer accounting on bundled
415 static inline void sctp_skb_set_owner_r(struct sk_buff
*skb
, struct sock
*sk
)
417 struct sctp_ulpevent
*event
= sctp_skb2event(skb
);
421 skb
->destructor
= sctp_sock_rfree
;
422 atomic_add(event
->rmem_len
, &sk
->sk_rmem_alloc
);
424 * This mimics the behavior of skb_set_owner_r
426 sk
->sk_forward_alloc
-= event
->rmem_len
;
429 /* Tests if the list has one and only one entry. */
430 static inline int sctp_list_single_entry(struct list_head
*head
)
432 return (head
->next
!= head
) && (head
->next
== head
->prev
);
435 /* Break down data chunks at this point. */
436 static inline int sctp_frag_point(const struct sctp_association
*asoc
, int pmtu
)
438 struct sctp_sock
*sp
= sctp_sk(asoc
->base
.sk
);
441 frag
-= sp
->pf
->af
->net_header_len
;
442 frag
-= sizeof(struct sctphdr
) + sizeof(struct sctp_data_chunk
);
445 frag
= min_t(int, frag
, asoc
->user_frag
);
447 frag
= SCTP_TRUNC4(min_t(int, frag
, SCTP_MAX_CHUNK_LEN
-
448 sizeof(struct sctp_data_chunk
)));
453 static inline void sctp_assoc_pending_pmtu(struct sctp_association
*asoc
)
455 sctp_assoc_sync_pmtu(asoc
);
456 asoc
->pmtu_pending
= 0;
459 static inline bool sctp_chunk_pending(const struct sctp_chunk
*chunk
)
461 return !list_empty(&chunk
->list
);
464 /* Walk through a list of TLV parameters. Don't trust the
465 * individual parameter lengths and instead depend on
466 * the chunk length to indicate when to stop. Make sure
467 * there is room for a param header too.
469 #define sctp_walk_params(pos, chunk, member)\
470 _sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length), member)
472 #define _sctp_walk_params(pos, chunk, end, member)\
473 for (pos.v = chunk->member;\
474 (pos.v + offsetof(struct sctp_paramhdr, length) + sizeof(pos.p->length) <=\
475 (void *)chunk + end) &&\
476 pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\
477 ntohs(pos.p->length) >= sizeof(struct sctp_paramhdr);\
478 pos.v += SCTP_PAD4(ntohs(pos.p->length)))
480 #define sctp_walk_errors(err, chunk_hdr)\
481 _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
483 #define _sctp_walk_errors(err, chunk_hdr, end)\
484 for (err = (struct sctp_errhdr *)((void *)chunk_hdr + \
485 sizeof(struct sctp_chunkhdr));\
486 ((void *)err + offsetof(struct sctp_errhdr, length) + sizeof(err->length) <=\
487 (void *)chunk_hdr + end) &&\
488 (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\
489 ntohs(err->length) >= sizeof(struct sctp_errhdr); \
490 err = (struct sctp_errhdr *)((void *)err + SCTP_PAD4(ntohs(err->length))))
492 #define sctp_walk_fwdtsn(pos, chunk)\
493 _sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk))
495 #define _sctp_walk_fwdtsn(pos, chunk, end)\
496 for (pos = chunk->subh.fwdtsn_hdr->skip;\
497 (void *)pos <= (void *)chunk->subh.fwdtsn_hdr->skip + end - sizeof(struct sctp_fwdtsn_skip);\
500 /* External references. */
502 extern struct proto sctp_prot
;
503 extern struct proto sctpv6_prot
;
504 void sctp_put_port(struct sock
*sk
);
506 extern struct idr sctp_assocs_id
;
507 extern spinlock_t sctp_assocs_id_lock
;
509 /* Static inline functions. */
511 /* Convert from an IP version number to an Address Family symbol. */
512 static inline int ipver2af(__u8 ipver
)
524 /* Convert from an address parameter type to an address family. */
525 static inline int param_type2af(__be16 type
)
528 case SCTP_PARAM_IPV4_ADDRESS
:
530 case SCTP_PARAM_IPV6_ADDRESS
:
537 /* Warning: The following hash functions assume a power of two 'size'. */
538 /* This is the hash function for the SCTP port hash table. */
539 static inline int sctp_phashfn(struct net
*net
, __u16 lport
)
541 return (net_hash_mix(net
) + lport
) & (sctp_port_hashsize
- 1);
544 /* This is the hash function for the endpoint hash table. */
545 static inline int sctp_ep_hashfn(struct net
*net
, __u16 lport
)
547 return (net_hash_mix(net
) + lport
) & (sctp_ep_hashsize
- 1);
550 #define sctp_for_each_hentry(epb, head) \
551 hlist_for_each_entry(epb, head, node)
553 /* Is a socket of this style? */
554 #define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
555 static inline int __sctp_style(const struct sock
*sk
,
556 enum sctp_socket_type style
)
558 return sctp_sk(sk
)->type
== style
;
561 /* Is the association in this state? */
562 #define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state))
563 static inline int __sctp_state(const struct sctp_association
*asoc
,
564 enum sctp_state state
)
566 return asoc
->state
== state
;
569 /* Is the socket in this state? */
570 #define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state))
571 static inline int __sctp_sstate(const struct sock
*sk
,
572 enum sctp_sock_state state
)
574 return sk
->sk_state
== state
;
577 /* Map v4-mapped v6 address back to v4 address */
578 static inline void sctp_v6_map_v4(union sctp_addr
*addr
)
580 addr
->v4
.sin_family
= AF_INET
;
581 addr
->v4
.sin_port
= addr
->v6
.sin6_port
;
582 addr
->v4
.sin_addr
.s_addr
= addr
->v6
.sin6_addr
.s6_addr32
[3];
585 /* Map v4 address to v4-mapped v6 address */
586 static inline void sctp_v4_map_v6(union sctp_addr
*addr
)
590 port
= addr
->v4
.sin_port
;
591 addr
->v6
.sin6_addr
.s6_addr32
[3] = addr
->v4
.sin_addr
.s_addr
;
592 addr
->v6
.sin6_port
= port
;
593 addr
->v6
.sin6_family
= AF_INET6
;
594 addr
->v6
.sin6_flowinfo
= 0;
595 addr
->v6
.sin6_scope_id
= 0;
596 addr
->v6
.sin6_addr
.s6_addr32
[0] = 0;
597 addr
->v6
.sin6_addr
.s6_addr32
[1] = 0;
598 addr
->v6
.sin6_addr
.s6_addr32
[2] = htonl(0x0000ffff);
601 /* The cookie is always 0 since this is how it's used in the
604 static inline struct dst_entry
*sctp_transport_dst_check(struct sctp_transport
*t
)
606 if (t
->dst
&& !dst_check(t
->dst
, t
->dst_cookie
))
607 sctp_transport_dst_release(t
);
612 static inline bool sctp_transport_pmtu_check(struct sctp_transport
*t
)
614 __u32 pmtu
= max_t(size_t, SCTP_TRUNC4(dst_mtu(t
->dst
)),
615 SCTP_DEFAULT_MINSEGMENT
);
617 if (t
->pathmtu
== pmtu
)
625 #endif /* __net_sctp_h__ */