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) 2001-2003 Intel Corp.
7 *
8 * This file is part of the SCTP kernel implementation
9 *
10 * The base lksctp header.
11 *
12 * Please send any bug reports or fixes you make to the
13 * email address(es):
14 * lksctp developers <linux-sctp@vger.kernel.org>
15 *
16 * Written or modified by:
17 * La Monte H.P. Yarroll <piggy@acm.org>
18 * Xingang Guo <xingang.guo@intel.com>
19 * Jon Grimm <jgrimm@us.ibm.com>
20 * Daisy Chang <daisyc@us.ibm.com>
21 * Sridhar Samudrala <sri@us.ibm.com>
22 * Ardelle Fan <ardelle.fan@intel.com>
23 * Ryan Layer <rmlayer@us.ibm.com>
24 * Kevin Gao <kevin.gao@intel.com>
25 */
26
27 #ifndef __net_sctp_h__
28 #define __net_sctp_h__
29
30 /* Header Strategy.
31 * Start getting some control over the header file depencies:
32 * includes
33 * constants
34 * structs
35 * prototypes
36 * macros, externs, and inlines
37 *
38 * Move test_frame specific items out of the kernel headers
39 * and into the test frame headers. This is not perfect in any sense
40 * and will continue to evolve.
41 */
42
43 #include <linux/types.h>
44 #include <linux/slab.h>
45 #include <linux/in.h>
46 #include <linux/tty.h>
47 #include <linux/proc_fs.h>
48 #include <linux/spinlock.h>
49 #include <linux/jiffies.h>
50 #include <linux/idr.h>
51
52 #if IS_ENABLED(CONFIG_IPV6)
53 #include <net/ipv6.h>
54 #include <net/ip6_route.h>
55 #endif
56
57 #include <linux/uaccess.h>
58 #include <asm/page.h>
59 #include <net/sock.h>
60 #include <net/snmp.h>
61 #include <net/sctp/structs.h>
62 #include <net/sctp/constants.h>
63
64 #ifdef CONFIG_IP_SCTP_MODULE
65 #define SCTP_PROTOSW_FLAG 0
66 #else /* static! */
67 #define SCTP_PROTOSW_FLAG INET_PROTOSW_PERMANENT
68 #endif
69
70 /* Round an int up to the next multiple of 4. */
71 #define SCTP_PAD4(s) (((s)+3)&~3)
72 /* Truncate to the previous multiple of 4. */
73 #define SCTP_TRUNC4(s) ((s)&~3)
74
75 /*
76 * Function declarations.
77 */
78
79 /*
80 * sctp/protocol.c
81 */
82 int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *addr,
83 enum sctp_scope, gfp_t gfp, int flags);
84 struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
85 int sctp_register_pf(struct sctp_pf *, sa_family_t);
86 void sctp_addr_wq_mgmt(struct net *, struct sctp_sockaddr_entry *, int);
87
88 /*
89 * sctp/socket.c
90 */
91 int sctp_inet_connect(struct socket *sock, struct sockaddr *uaddr,
92 int addr_len, int flags);
93 int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
94 int sctp_inet_listen(struct socket *sock, int backlog);
95 void sctp_write_space(struct sock *sk);
96 void sctp_data_ready(struct sock *sk);
97 __poll_t sctp_poll(struct file *file, struct socket *sock,
98 poll_table *wait);
99 void sctp_sock_rfree(struct sk_buff *skb);
100 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
101 struct sctp_association *asoc);
102 extern struct percpu_counter sctp_sockets_allocated;
103 int sctp_asconf_mgmt(struct sctp_sock *, struct sctp_sockaddr_entry *);
104 struct sk_buff *sctp_skb_recv_datagram(struct sock *, int, int, int *);
105
106 void sctp_transport_walk_start(struct rhashtable_iter *iter);
107 void sctp_transport_walk_stop(struct rhashtable_iter *iter);
108 struct sctp_transport *sctp_transport_get_next(struct net *net,
109 struct rhashtable_iter *iter);
110 struct sctp_transport *sctp_transport_get_idx(struct net *net,
111 struct rhashtable_iter *iter, int pos);
112 int sctp_transport_lookup_process(int (*cb)(struct sctp_transport *, void *),
113 struct net *net,
114 const union sctp_addr *laddr,
115 const union sctp_addr *paddr, void *p);
116 int sctp_for_each_transport(int (*cb)(struct sctp_transport *, void *),
117 int (*cb_done)(struct sctp_transport *, void *),
118 struct net *net, int *pos, void *p);
119 int sctp_for_each_endpoint(int (*cb)(struct sctp_endpoint *, void *), void *p);
120 int sctp_get_sctp_info(struct sock *sk, struct sctp_association *asoc,
121 struct sctp_info *info);
122
123 /*
124 * sctp/primitive.c
125 */
126 int sctp_primitive_ASSOCIATE(struct net *, struct sctp_association *, void *arg);
127 int sctp_primitive_SHUTDOWN(struct net *, struct sctp_association *, void *arg);
128 int sctp_primitive_ABORT(struct net *, struct sctp_association *, void *arg);
129 int sctp_primitive_SEND(struct net *, struct sctp_association *, void *arg);
130 int sctp_primitive_REQUESTHEARTBEAT(struct net *, struct sctp_association *, void *arg);
131 int sctp_primitive_ASCONF(struct net *, struct sctp_association *, void *arg);
132 int sctp_primitive_RECONF(struct net *net, struct sctp_association *asoc,
133 void *arg);
134
135 /*
136 * sctp/input.c
137 */
138 int sctp_rcv(struct sk_buff *skb);
139 int sctp_v4_err(struct sk_buff *skb, u32 info);
140 int sctp_hash_endpoint(struct sctp_endpoint *ep);
141 void sctp_unhash_endpoint(struct sctp_endpoint *);
142 struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *,
143 struct sctphdr *, struct sctp_association **,
144 struct sctp_transport **);
145 void sctp_err_finish(struct sock *, struct sctp_transport *);
146 void sctp_icmp_frag_needed(struct sock *, struct sctp_association *,
147 struct sctp_transport *t, __u32 pmtu);
148 void sctp_icmp_redirect(struct sock *, struct sctp_transport *,
149 struct sk_buff *);
150 void sctp_icmp_proto_unreachable(struct sock *sk,
151 struct sctp_association *asoc,
152 struct sctp_transport *t);
153 void sctp_backlog_migrate(struct sctp_association *assoc,
154 struct sock *oldsk, struct sock *newsk);
155 int sctp_transport_hashtable_init(void);
156 void sctp_transport_hashtable_destroy(void);
157 int sctp_hash_transport(struct sctp_transport *t);
158 void sctp_unhash_transport(struct sctp_transport *t);
159 struct sctp_transport *sctp_addrs_lookup_transport(
160 struct net *net,
161 const union sctp_addr *laddr,
162 const union sctp_addr *paddr);
163 struct sctp_transport *sctp_epaddr_lookup_transport(
164 const struct sctp_endpoint *ep,
165 const union sctp_addr *paddr);
166
167 /*
168 * sctp/proc.c
169 */
170 int __net_init sctp_proc_init(struct net *net);
171
172 /*
173 * sctp/offload.c
174 */
175 int sctp_offload_init(void);
176
177 /*
178 * sctp/stream_sched.c
179 */
180 void sctp_sched_ops_init(void);
181
182 /*
183 * sctp/stream.c
184 */
185 int sctp_send_reset_streams(struct sctp_association *asoc,
186 struct sctp_reset_streams *params);
187 int sctp_send_reset_assoc(struct sctp_association *asoc);
188 int sctp_send_add_streams(struct sctp_association *asoc,
189 struct sctp_add_streams *params);
190
191 /*
192 * Module global variables
193 */
194
195 /*
196 * sctp/protocol.c
197 */
198 extern struct kmem_cache *sctp_chunk_cachep __read_mostly;
199 extern struct kmem_cache *sctp_bucket_cachep __read_mostly;
200 extern long sysctl_sctp_mem[3];
201 extern int sysctl_sctp_rmem[3];
202 extern int sysctl_sctp_wmem[3];
203
204 /*
205 * Section: Macros, externs, and inlines
206 */
207
208 /* SCTP SNMP MIB stats handlers */
209 #define SCTP_INC_STATS(net, field) SNMP_INC_STATS((net)->sctp.sctp_statistics, field)
210 #define __SCTP_INC_STATS(net, field) __SNMP_INC_STATS((net)->sctp.sctp_statistics, field)
211 #define SCTP_DEC_STATS(net, field) SNMP_DEC_STATS((net)->sctp.sctp_statistics, field)
212
213 /* sctp mib definitions */
214 enum {
215 SCTP_MIB_NUM = 0,
216 SCTP_MIB_CURRESTAB, /* CurrEstab */
217 SCTP_MIB_ACTIVEESTABS, /* ActiveEstabs */
218 SCTP_MIB_PASSIVEESTABS, /* PassiveEstabs */
219 SCTP_MIB_ABORTEDS, /* Aborteds */
220 SCTP_MIB_SHUTDOWNS, /* Shutdowns */
221 SCTP_MIB_OUTOFBLUES, /* OutOfBlues */
222 SCTP_MIB_CHECKSUMERRORS, /* ChecksumErrors */
223 SCTP_MIB_OUTCTRLCHUNKS, /* OutCtrlChunks */
224 SCTP_MIB_OUTORDERCHUNKS, /* OutOrderChunks */
225 SCTP_MIB_OUTUNORDERCHUNKS, /* OutUnorderChunks */
226 SCTP_MIB_INCTRLCHUNKS, /* InCtrlChunks */
227 SCTP_MIB_INORDERCHUNKS, /* InOrderChunks */
228 SCTP_MIB_INUNORDERCHUNKS, /* InUnorderChunks */
229 SCTP_MIB_FRAGUSRMSGS, /* FragUsrMsgs */
230 SCTP_MIB_REASMUSRMSGS, /* ReasmUsrMsgs */
231 SCTP_MIB_OUTSCTPPACKS, /* OutSCTPPacks */
232 SCTP_MIB_INSCTPPACKS, /* InSCTPPacks */
233 SCTP_MIB_T1_INIT_EXPIREDS,
234 SCTP_MIB_T1_COOKIE_EXPIREDS,
235 SCTP_MIB_T2_SHUTDOWN_EXPIREDS,
236 SCTP_MIB_T3_RTX_EXPIREDS,
237 SCTP_MIB_T4_RTO_EXPIREDS,
238 SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS,
239 SCTP_MIB_DELAY_SACK_EXPIREDS,
240 SCTP_MIB_AUTOCLOSE_EXPIREDS,
241 SCTP_MIB_T1_RETRANSMITS,
242 SCTP_MIB_T3_RETRANSMITS,
243 SCTP_MIB_PMTUD_RETRANSMITS,
244 SCTP_MIB_FAST_RETRANSMITS,
245 SCTP_MIB_IN_PKT_SOFTIRQ,
246 SCTP_MIB_IN_PKT_BACKLOG,
247 SCTP_MIB_IN_PKT_DISCARDS,
248 SCTP_MIB_IN_DATA_CHUNK_DISCARDS,
249 __SCTP_MIB_MAX
250 };
251
252 #define SCTP_MIB_MAX __SCTP_MIB_MAX
253 struct sctp_mib {
254 unsigned long mibs[SCTP_MIB_MAX];
255 };
256
257 /* helper function to track stats about max rto and related transport */
sctp_max_rto(struct sctp_association * asoc,struct sctp_transport * trans)258 static inline void sctp_max_rto(struct sctp_association *asoc,
259 struct sctp_transport *trans)
260 {
261 if (asoc->stats.max_obs_rto < (__u64)trans->rto) {
262 asoc->stats.max_obs_rto = trans->rto;
263 memset(&asoc->stats.obs_rto_ipaddr, 0,
264 sizeof(struct sockaddr_storage));
265 memcpy(&asoc->stats.obs_rto_ipaddr, &trans->ipaddr,
266 trans->af_specific->sockaddr_len);
267 }
268 }
269
270 /*
271 * Macros for keeping a global reference of object allocations.
272 */
273 #ifdef CONFIG_SCTP_DBG_OBJCNT
274
275 extern atomic_t sctp_dbg_objcnt_sock;
276 extern atomic_t sctp_dbg_objcnt_ep;
277 extern atomic_t sctp_dbg_objcnt_assoc;
278 extern atomic_t sctp_dbg_objcnt_transport;
279 extern atomic_t sctp_dbg_objcnt_chunk;
280 extern atomic_t sctp_dbg_objcnt_bind_addr;
281 extern atomic_t sctp_dbg_objcnt_bind_bucket;
282 extern atomic_t sctp_dbg_objcnt_addr;
283 extern atomic_t sctp_dbg_objcnt_datamsg;
284 extern atomic_t sctp_dbg_objcnt_keys;
285
286 /* Macros to atomically increment/decrement objcnt counters. */
287 #define SCTP_DBG_OBJCNT_INC(name) \
288 atomic_inc(&sctp_dbg_objcnt_## name)
289 #define SCTP_DBG_OBJCNT_DEC(name) \
290 atomic_dec(&sctp_dbg_objcnt_## name)
291 #define SCTP_DBG_OBJCNT(name) \
292 atomic_t sctp_dbg_objcnt_## name = ATOMIC_INIT(0)
293
294 /* Macro to help create new entries in in the global array of
295 * objcnt counters.
296 */
297 #define SCTP_DBG_OBJCNT_ENTRY(name) \
298 {.label= #name, .counter= &sctp_dbg_objcnt_## name}
299
300 void sctp_dbg_objcnt_init(struct net *);
301
302 #else
303
304 #define SCTP_DBG_OBJCNT_INC(name)
305 #define SCTP_DBG_OBJCNT_DEC(name)
306
sctp_dbg_objcnt_init(struct net * net)307 static inline void sctp_dbg_objcnt_init(struct net *net) { return; }
308
309 #endif /* CONFIG_SCTP_DBG_OBJCOUNT */
310
311 #if defined CONFIG_SYSCTL
312 void sctp_sysctl_register(void);
313 void sctp_sysctl_unregister(void);
314 int sctp_sysctl_net_register(struct net *net);
315 void sctp_sysctl_net_unregister(struct net *net);
316 #else
sctp_sysctl_register(void)317 static inline void sctp_sysctl_register(void) { return; }
sctp_sysctl_unregister(void)318 static inline void sctp_sysctl_unregister(void) { return; }
sctp_sysctl_net_register(struct net * net)319 static inline int sctp_sysctl_net_register(struct net *net) { return 0; }
sctp_sysctl_net_unregister(struct net * net)320 static inline void sctp_sysctl_net_unregister(struct net *net) { return; }
321 #endif
322
323 /* Size of Supported Address Parameter for 'x' address types. */
324 #define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16))
325
326 #if IS_ENABLED(CONFIG_IPV6)
327
328 void sctp_v6_pf_init(void);
329 void sctp_v6_pf_exit(void);
330 int sctp_v6_protosw_init(void);
331 void sctp_v6_protosw_exit(void);
332 int sctp_v6_add_protocol(void);
333 void sctp_v6_del_protocol(void);
334
335 #else /* #ifdef defined(CONFIG_IPV6) */
336
sctp_v6_pf_init(void)337 static inline void sctp_v6_pf_init(void) { return; }
sctp_v6_pf_exit(void)338 static inline void sctp_v6_pf_exit(void) { return; }
sctp_v6_protosw_init(void)339 static inline int sctp_v6_protosw_init(void) { return 0; }
sctp_v6_protosw_exit(void)340 static inline void sctp_v6_protosw_exit(void) { return; }
sctp_v6_add_protocol(void)341 static inline int sctp_v6_add_protocol(void) { return 0; }
sctp_v6_del_protocol(void)342 static inline void sctp_v6_del_protocol(void) { return; }
343
344 #endif /* #if defined(CONFIG_IPV6) */
345
346
347 /* Map an association to an assoc_id. */
sctp_assoc2id(const struct sctp_association * asoc)348 static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc)
349 {
350 return asoc ? asoc->assoc_id : 0;
351 }
352
353 static inline enum sctp_sstat_state
sctp_assoc_to_state(const struct sctp_association * asoc)354 sctp_assoc_to_state(const struct sctp_association *asoc)
355 {
356 /* SCTP's uapi always had SCTP_EMPTY(=0) as a dummy state, but we
357 * got rid of it in kernel space. Therefore SCTP_CLOSED et al
358 * start at =1 in user space, but actually as =0 in kernel space.
359 * Now that we can not break user space and SCTP_EMPTY is exposed
360 * there, we need to fix it up with an ugly offset not to break
361 * applications. :(
362 */
363 return asoc->state + 1;
364 }
365
366 /* Look up the association by its id. */
367 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);
368
369 int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp);
370
371 /* A macro to walk a list of skbs. */
372 #define sctp_skb_for_each(pos, head, tmp) \
373 skb_queue_walk_safe(head, pos, tmp)
374
375 /**
376 * sctp_list_dequeue - remove from the head of the queue
377 * @list: list to dequeue from
378 *
379 * Remove the head of the list. The head item is
380 * returned or %NULL if the list is empty.
381 */
382
sctp_list_dequeue(struct list_head * list)383 static inline struct list_head *sctp_list_dequeue(struct list_head *list)
384 {
385 struct list_head *result = NULL;
386
387 if (!list_empty(list)) {
388 result = list->next;
389 list_del_init(result);
390 }
391 return result;
392 }
393
394 /* SCTP version of skb_set_owner_r. We need this one because
395 * of the way we have to do receive buffer accounting on bundled
396 * chunks.
397 */
sctp_skb_set_owner_r(struct sk_buff * skb,struct sock * sk)398 static inline void sctp_skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
399 {
400 struct sctp_ulpevent *event = sctp_skb2event(skb);
401
402 skb_orphan(skb);
403 skb->sk = sk;
404 skb->destructor = sctp_sock_rfree;
405 atomic_add(event->rmem_len, &sk->sk_rmem_alloc);
406 /*
407 * This mimics the behavior of skb_set_owner_r
408 */
409 sk_mem_charge(sk, event->rmem_len);
410 }
411
412 /* Tests if the list has one and only one entry. */
sctp_list_single_entry(struct list_head * head)413 static inline int sctp_list_single_entry(struct list_head *head)
414 {
415 return (head->next != head) && (head->next == head->prev);
416 }
417
sctp_chunk_pending(const struct sctp_chunk * chunk)418 static inline bool sctp_chunk_pending(const struct sctp_chunk *chunk)
419 {
420 return !list_empty(&chunk->list);
421 }
422
423 /* Walk through a list of TLV parameters. Don't trust the
424 * individual parameter lengths and instead depend on
425 * the chunk length to indicate when to stop. Make sure
426 * there is room for a param header too.
427 */
428 #define sctp_walk_params(pos, chunk, member)\
429 _sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length), member)
430
431 #define _sctp_walk_params(pos, chunk, end, member)\
432 for (pos.v = chunk->member;\
433 (pos.v + offsetof(struct sctp_paramhdr, length) + sizeof(pos.p->length) <=\
434 (void *)chunk + end) &&\
435 pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\
436 ntohs(pos.p->length) >= sizeof(struct sctp_paramhdr);\
437 pos.v += SCTP_PAD4(ntohs(pos.p->length)))
438
439 #define sctp_walk_errors(err, chunk_hdr)\
440 _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
441
442 #define _sctp_walk_errors(err, chunk_hdr, end)\
443 for (err = (struct sctp_errhdr *)((void *)chunk_hdr + \
444 sizeof(struct sctp_chunkhdr));\
445 ((void *)err + offsetof(struct sctp_errhdr, length) + sizeof(err->length) <=\
446 (void *)chunk_hdr + end) &&\
447 (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\
448 ntohs(err->length) >= sizeof(struct sctp_errhdr); \
449 err = (struct sctp_errhdr *)((void *)err + SCTP_PAD4(ntohs(err->length))))
450
451 #define sctp_walk_fwdtsn(pos, chunk)\
452 _sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk))
453
454 #define _sctp_walk_fwdtsn(pos, chunk, end)\
455 for (pos = chunk->subh.fwdtsn_hdr->skip;\
456 (void *)pos <= (void *)chunk->subh.fwdtsn_hdr->skip + end - sizeof(struct sctp_fwdtsn_skip);\
457 pos++)
458
459 /* External references. */
460
461 extern struct proto sctp_prot;
462 extern struct proto sctpv6_prot;
463 void sctp_put_port(struct sock *sk);
464
465 extern struct idr sctp_assocs_id;
466 extern spinlock_t sctp_assocs_id_lock;
467
468 /* Static inline functions. */
469
470 /* Convert from an IP version number to an Address Family symbol. */
ipver2af(__u8 ipver)471 static inline int ipver2af(__u8 ipver)
472 {
473 switch (ipver) {
474 case 4:
475 return AF_INET;
476 case 6:
477 return AF_INET6;
478 default:
479 return 0;
480 }
481 }
482
483 /* Convert from an address parameter type to an address family. */
param_type2af(__be16 type)484 static inline int param_type2af(__be16 type)
485 {
486 switch (type) {
487 case SCTP_PARAM_IPV4_ADDRESS:
488 return AF_INET;
489 case SCTP_PARAM_IPV6_ADDRESS:
490 return AF_INET6;
491 default:
492 return 0;
493 }
494 }
495
496 /* Warning: The following hash functions assume a power of two 'size'. */
497 /* This is the hash function for the SCTP port hash table. */
sctp_phashfn(struct net * net,__u16 lport)498 static inline int sctp_phashfn(struct net *net, __u16 lport)
499 {
500 return (net_hash_mix(net) + lport) & (sctp_port_hashsize - 1);
501 }
502
503 /* This is the hash function for the endpoint hash table. */
sctp_ep_hashfn(struct net * net,__u16 lport)504 static inline int sctp_ep_hashfn(struct net *net, __u16 lport)
505 {
506 return (net_hash_mix(net) + lport) & (sctp_ep_hashsize - 1);
507 }
508
509 #define sctp_for_each_hentry(epb, head) \
510 hlist_for_each_entry(epb, head, node)
511
512 /* Is a socket of this style? */
513 #define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
__sctp_style(const struct sock * sk,enum sctp_socket_type style)514 static inline int __sctp_style(const struct sock *sk,
515 enum sctp_socket_type style)
516 {
517 return sctp_sk(sk)->type == style;
518 }
519
520 /* Is the association in this state? */
521 #define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state))
__sctp_state(const struct sctp_association * asoc,enum sctp_state state)522 static inline int __sctp_state(const struct sctp_association *asoc,
523 enum sctp_state state)
524 {
525 return asoc->state == state;
526 }
527
528 /* Is the socket in this state? */
529 #define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state))
__sctp_sstate(const struct sock * sk,enum sctp_sock_state state)530 static inline int __sctp_sstate(const struct sock *sk,
531 enum sctp_sock_state state)
532 {
533 return sk->sk_state == state;
534 }
535
536 /* Map v4-mapped v6 address back to v4 address */
sctp_v6_map_v4(union sctp_addr * addr)537 static inline void sctp_v6_map_v4(union sctp_addr *addr)
538 {
539 addr->v4.sin_family = AF_INET;
540 addr->v4.sin_port = addr->v6.sin6_port;
541 addr->v4.sin_addr.s_addr = addr->v6.sin6_addr.s6_addr32[3];
542 }
543
544 /* Map v4 address to v4-mapped v6 address */
sctp_v4_map_v6(union sctp_addr * addr)545 static inline void sctp_v4_map_v6(union sctp_addr *addr)
546 {
547 __be16 port;
548
549 port = addr->v4.sin_port;
550 addr->v6.sin6_addr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
551 addr->v6.sin6_port = port;
552 addr->v6.sin6_family = AF_INET6;
553 addr->v6.sin6_flowinfo = 0;
554 addr->v6.sin6_scope_id = 0;
555 addr->v6.sin6_addr.s6_addr32[0] = 0;
556 addr->v6.sin6_addr.s6_addr32[1] = 0;
557 addr->v6.sin6_addr.s6_addr32[2] = htonl(0x0000ffff);
558 }
559
560 /* The cookie is always 0 since this is how it's used in the
561 * pmtu code.
562 */
sctp_transport_dst_check(struct sctp_transport * t)563 static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t)
564 {
565 if (t->dst && !dst_check(t->dst, t->dst_cookie))
566 sctp_transport_dst_release(t);
567
568 return t->dst;
569 }
570
571 /* Calculate max payload size given a MTU, or the total overhead if
572 * given MTU is zero
573 */
sctp_mtu_payload(const struct sctp_sock * sp,__u32 mtu,__u32 extra)574 static inline __u32 sctp_mtu_payload(const struct sctp_sock *sp,
575 __u32 mtu, __u32 extra)
576 {
577 __u32 overhead = sizeof(struct sctphdr) + extra;
578
579 if (sp)
580 overhead += sp->pf->af->net_header_len;
581 else
582 overhead += sizeof(struct ipv6hdr);
583
584 if (WARN_ON_ONCE(mtu && mtu <= overhead))
585 mtu = overhead;
586
587 return mtu ? mtu - overhead : overhead;
588 }
589
sctp_dst_mtu(const struct dst_entry * dst)590 static inline __u32 sctp_dst_mtu(const struct dst_entry *dst)
591 {
592 return SCTP_TRUNC4(max_t(__u32, dst_mtu(dst),
593 SCTP_DEFAULT_MINSEGMENT));
594 }
595
sctp_transport_pmtu_check(struct sctp_transport * t)596 static inline bool sctp_transport_pmtu_check(struct sctp_transport *t)
597 {
598 __u32 pmtu = sctp_dst_mtu(t->dst);
599
600 if (t->pathmtu == pmtu)
601 return true;
602
603 t->pathmtu = pmtu;
604
605 return false;
606 }
607
sctp_min_frag_point(struct sctp_sock * sp,__u16 datasize)608 static inline __u32 sctp_min_frag_point(struct sctp_sock *sp, __u16 datasize)
609 {
610 return sctp_mtu_payload(sp, SCTP_DEFAULT_MINSEGMENT, datasize);
611 }
612
sctp_newsk_ready(const struct sock * sk)613 static inline bool sctp_newsk_ready(const struct sock *sk)
614 {
615 return sock_flag(sk, SOCK_DEAD) || sk->sk_socket;
616 }
617
618 #endif /* __net_sctp_h__ */
619
