include/net/sctp/sctp.h

   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, write to
  25  * the Free Software Foundation, 59 Temple Place - Suite 330,
  26  * Boston, MA 02111-1307, USA.
  27  *
  28  * Please send any bug reports or fixes you make to the
  29  * email address(es):
  30  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
  31  *
  32  * Or submit a bug report through the following website:
  33  *    http://www.sf.net/projects/lksctp
  34  *
  35  * Written or modified by:
  36  *    La Monte H.P. Yarroll <piggy@acm.org>
  37  *    Xingang Guo           <xingang.guo@intel.com>
  38  *    Jon Grimm             <jgrimm@us.ibm.com>
  39  *    Daisy Chang           <daisyc@us.ibm.com>
  40  *    Sridhar Samudrala     <sri@us.ibm.com>
  41  *    Ardelle Fan           <ardelle.fan@intel.com>
  42  *    Ryan Layer            <rmlayer@us.ibm.com>
  43  *    Kevin Gao             <kevin.gao@intel.com>
  44  *
  45  * Any bugs reported given to us we will try to fix... any fixes shared will
  46  * be incorporated into the next SCTP release.
  47  */
  48
  49 #ifndef __net_sctp_h__
  50 #define __net_sctp_h__
  51
  52 /* Header Strategy.
  53  *    Start getting some control over the header file depencies:
  54  *       includes
  55  *       constants
  56  *       structs
  57  *       prototypes
  58  *       macros, externs, and inlines
  59  *
  60  *   Move test_frame specific items out of the kernel headers
  61  *   and into the test frame headers.   This is not perfect in any sense
  62  *   and will continue to evolve.
  63  */
  64
  65 #include <linux/types.h>
  66 #include <linux/slab.h>
  67 #include <linux/in.h>
  68 #include <linux/tty.h>
  69 #include <linux/proc_fs.h>
  70 #include <linux/spinlock.h>
  71 #include <linux/jiffies.h>
  72 #include <linux/idr.h>
  73
  74 #if IS_ENABLED(CONFIG_IPV6)
  75 #include <net/ipv6.h>
  76 #include <net/ip6_route.h>
  77 #endif
  78
  79 #include <asm/uaccess.h>
  80 #include <asm/page.h>
  81 #include <net/sock.h>
  82 #include <net/snmp.h>
  83 #include <net/sctp/structs.h>
  84 #include <net/sctp/constants.h>
  85
  86 #ifdef CONFIG_IP_SCTP_MODULE
  87 #define SCTP_PROTOSW_FLAG 0
  88 #else /* static! */
  89 #define SCTP_PROTOSW_FLAG INET_PROTOSW_PERMANENT
  90 #endif
  91
  92 /*
  93  * Function declarations.
  94  */
  95
  96 /*
  97  * sctp/protocol.c
  98  */
  99 extern int sctp_copy_local_addr_list(struct net *, struct sctp_bind_addr *,
 100                                      sctp_scope_t, gfp_t gfp,
 101                                      int flags);
 102 extern struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
 103 extern int sctp_register_pf(struct sctp_pf *, sa_family_t);
 104 extern void sctp_addr_wq_mgmt(struct net *, struct sctp_sockaddr_entry *, int);
 105
 106 /*
 107  * sctp/socket.c
 108  */
 109 int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
 110 int sctp_inet_listen(struct socket *sock, int backlog);
 111 void sctp_write_space(struct sock *sk);
 112 void sctp_data_ready(struct sock *sk, int len);
 113 unsigned int sctp_poll(struct file *file, struct socket *sock,
 114                 poll_table *wait);
 115 void sctp_sock_rfree(struct sk_buff *skb);
 116 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
 117                     struct sctp_association *asoc);
 118 extern struct percpu_counter sctp_sockets_allocated;
 119 extern int sctp_asconf_mgmt(struct sctp_sock *, struct sctp_sockaddr_entry *);
 120
 121 /*
 122  * sctp/primitive.c
 123  */
 124 int sctp_primitive_ASSOCIATE(struct net *, struct sctp_association *, void *arg);
 125 int sctp_primitive_SHUTDOWN(struct net *, struct sctp_association *, void *arg);
 126 int sctp_primitive_ABORT(struct net *, struct sctp_association *, void *arg);
 127 int sctp_primitive_SEND(struct net *, struct sctp_association *, void *arg);
 128 int sctp_primitive_REQUESTHEARTBEAT(struct net *, struct sctp_association *, void *arg);
 129 int sctp_primitive_ASCONF(struct net *, struct sctp_association *, void *arg);
 130
 131 /*
 132  * sctp/input.c
 133  */
 134 int sctp_rcv(struct sk_buff *skb);
 135 void sctp_v4_err(struct sk_buff *skb, u32 info);
 136 void sctp_hash_established(struct sctp_association *);
 137 void sctp_unhash_established(struct sctp_association *);
 138 void sctp_hash_endpoint(struct sctp_endpoint *);
 139 void sctp_unhash_endpoint(struct sctp_endpoint *);
 140 struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *,
 141                              struct sctphdr *, struct sctp_association **,
 142                              struct sctp_transport **);
 143 void sctp_err_finish(struct sock *, struct sctp_association *);
 144 void sctp_icmp_frag_needed(struct sock *, struct sctp_association *,
 145                            struct sctp_transport *t, __u32 pmtu);
 146 void sctp_icmp_redirect(struct sock *, struct sctp_transport *,
 147                         struct sk_buff *);
 148 void sctp_icmp_proto_unreachable(struct sock *sk,
 149                                  struct sctp_association *asoc,
 150                                  struct sctp_transport *t);
 151 void sctp_backlog_migrate(struct sctp_association *assoc,
 152                           struct sock *oldsk, struct sock *newsk);
 153
 154 /*
 155  * sctp/proc.c
 156  */
 157 int sctp_snmp_proc_init(struct net *net);
 158 void sctp_snmp_proc_exit(struct net *net);
 159 int sctp_eps_proc_init(struct net *net);
 160 void sctp_eps_proc_exit(struct net *net);
 161 int sctp_assocs_proc_init(struct net *net);
 162 void sctp_assocs_proc_exit(struct net *net);
 163 int sctp_remaddr_proc_init(struct net *net);
 164 void sctp_remaddr_proc_exit(struct net *net);
 165
 166
 167 /*
 168  * Module global variables
 169  */
 170
 171  /*
 172   * sctp/protocol.c
 173   */
 174 extern struct kmem_cache *sctp_chunk_cachep __read_mostly;
 175 extern struct kmem_cache *sctp_bucket_cachep __read_mostly;
 176
 177 /*
 178  *  Section:  Macros, externs, and inlines
 179  */
 180
 181 /* spin lock wrappers. */
 182 #define sctp_spin_lock_irqsave(lock, flags) spin_lock_irqsave(lock, flags)
 183 #define sctp_spin_unlock_irqrestore(lock, flags)  \
 184        spin_unlock_irqrestore(lock, flags)
 185 #define sctp_local_bh_disable() local_bh_disable()
 186 #define sctp_local_bh_enable()  local_bh_enable()
 187 #define sctp_spin_lock(lock)    spin_lock(lock)
 188 #define sctp_spin_unlock(lock)  spin_unlock(lock)
 189 #define sctp_write_lock(lock)   write_lock(lock)
 190 #define sctp_write_unlock(lock) write_unlock(lock)
 191 #define sctp_read_lock(lock)    read_lock(lock)
 192 #define sctp_read_unlock(lock)  read_unlock(lock)
 193
 194 /* sock lock wrappers. */
 195 #define sctp_lock_sock(sk)       lock_sock(sk)
 196 #define sctp_release_sock(sk)    release_sock(sk)
 197 #define sctp_bh_lock_sock(sk)    bh_lock_sock(sk)
 198 #define sctp_bh_unlock_sock(sk)  bh_unlock_sock(sk)
 199
 200 /* SCTP SNMP MIB stats handlers */
 201 #define SCTP_INC_STATS(net, field)      SNMP_INC_STATS((net)->sctp.sctp_statistics, field)
 202 #define SCTP_INC_STATS_BH(net, field)   SNMP_INC_STATS_BH((net)->sctp.sctp_statistics, field)
 203 #define SCTP_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)->sctp.sctp_statistics, field)
 204 #define SCTP_DEC_STATS(net, field)      SNMP_DEC_STATS((net)->sctp.sctp_statistics, field)
 205
 206 /* sctp mib definitions */
 207 enum {
 208         SCTP_MIB_NUM = 0,
 209         SCTP_MIB_CURRESTAB,                     /* CurrEstab */
 210         SCTP_MIB_ACTIVEESTABS,                  /* ActiveEstabs */
 211         SCTP_MIB_PASSIVEESTABS,                 /* PassiveEstabs */
 212         SCTP_MIB_ABORTEDS,                      /* Aborteds */
 213         SCTP_MIB_SHUTDOWNS,                     /* Shutdowns */
 214         SCTP_MIB_OUTOFBLUES,                    /* OutOfBlues */
 215         SCTP_MIB_CHECKSUMERRORS,                /* ChecksumErrors */
 216         SCTP_MIB_OUTCTRLCHUNKS,                 /* OutCtrlChunks */
 217         SCTP_MIB_OUTORDERCHUNKS,                /* OutOrderChunks */
 218         SCTP_MIB_OUTUNORDERCHUNKS,              /* OutUnorderChunks */
 219         SCTP_MIB_INCTRLCHUNKS,                  /* InCtrlChunks */
 220         SCTP_MIB_INORDERCHUNKS,                 /* InOrderChunks */
 221         SCTP_MIB_INUNORDERCHUNKS,               /* InUnorderChunks */
 222         SCTP_MIB_FRAGUSRMSGS,                   /* FragUsrMsgs */
 223         SCTP_MIB_REASMUSRMSGS,                  /* ReasmUsrMsgs */
 224         SCTP_MIB_OUTSCTPPACKS,                  /* OutSCTPPacks */
 225         SCTP_MIB_INSCTPPACKS,                   /* InSCTPPacks */
 226         SCTP_MIB_T1_INIT_EXPIREDS,
 227         SCTP_MIB_T1_COOKIE_EXPIREDS,
 228         SCTP_MIB_T2_SHUTDOWN_EXPIREDS,
 229         SCTP_MIB_T3_RTX_EXPIREDS,
 230         SCTP_MIB_T4_RTO_EXPIREDS,
 231         SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS,
 232         SCTP_MIB_DELAY_SACK_EXPIREDS,
 233         SCTP_MIB_AUTOCLOSE_EXPIREDS,
 234         SCTP_MIB_T1_RETRANSMITS,
 235         SCTP_MIB_T3_RETRANSMITS,
 236         SCTP_MIB_PMTUD_RETRANSMITS,
 237         SCTP_MIB_FAST_RETRANSMITS,
 238         SCTP_MIB_IN_PKT_SOFTIRQ,
 239         SCTP_MIB_IN_PKT_BACKLOG,
 240         SCTP_MIB_IN_PKT_DISCARDS,
 241         SCTP_MIB_IN_DATA_CHUNK_DISCARDS,
 242         __SCTP_MIB_MAX
 243 };
 244
 245 #define SCTP_MIB_MAX    __SCTP_MIB_MAX
 246 struct sctp_mib {
 247         unsigned long   mibs[SCTP_MIB_MAX];
 248 };
 249
 250 /* helper function to track stats about max rto and related transport */
 251 static inline void sctp_max_rto(struct sctp_association *asoc,
 252                                 struct sctp_transport *trans)
 253 {
 254         if (asoc->stats.max_obs_rto < (__u64)trans->rto) {
 255                 asoc->stats.max_obs_rto = trans->rto;
 256                 memset(&asoc->stats.obs_rto_ipaddr, 0,
 257                         sizeof(struct sockaddr_storage));
 258                 memcpy(&asoc->stats.obs_rto_ipaddr, &trans->ipaddr,
 259                         trans->af_specific->sockaddr_len);
 260         }
 261 }
 262
 263 /*
 264  * Macros for keeping a global reference of object allocations.
 265  */
 266 #ifdef CONFIG_SCTP_DBG_OBJCNT
 267
 268 extern atomic_t sctp_dbg_objcnt_sock;
 269 extern atomic_t sctp_dbg_objcnt_ep;
 270 extern atomic_t sctp_dbg_objcnt_assoc;
 271 extern atomic_t sctp_dbg_objcnt_transport;
 272 extern atomic_t sctp_dbg_objcnt_chunk;
 273 extern atomic_t sctp_dbg_objcnt_bind_addr;
 274 extern atomic_t sctp_dbg_objcnt_bind_bucket;
 275 extern atomic_t sctp_dbg_objcnt_addr;
 276 extern atomic_t sctp_dbg_objcnt_ssnmap;
 277 extern atomic_t sctp_dbg_objcnt_datamsg;
 278 extern atomic_t sctp_dbg_objcnt_keys;
 279
 280 /* Macros to atomically increment/decrement objcnt counters.  */
 281 #define SCTP_DBG_OBJCNT_INC(name) \
 282 atomic_inc(&sctp_dbg_objcnt_## name)
 283 #define SCTP_DBG_OBJCNT_DEC(name) \
 284 atomic_dec(&sctp_dbg_objcnt_## name)
 285 #define SCTP_DBG_OBJCNT(name) \
 286 atomic_t sctp_dbg_objcnt_## name = ATOMIC_INIT(0)
 287
 288 /* Macro to help create new entries in in the global array of
 289  * objcnt counters.
 290  */
 291 #define SCTP_DBG_OBJCNT_ENTRY(name) \
 292 {.label= #name, .counter= &sctp_dbg_objcnt_## name}
 293
 294 void sctp_dbg_objcnt_init(struct net *);
 295 void sctp_dbg_objcnt_exit(struct net *);
 296
 297 #else
 298
 299 #define SCTP_DBG_OBJCNT_INC(name)
 300 #define SCTP_DBG_OBJCNT_DEC(name)
 301
 302 static inline void sctp_dbg_objcnt_init(struct net *net) { return; }
 303 static inline void sctp_dbg_objcnt_exit(struct net *net) { return; }
 304
 305 #endif /* CONFIG_SCTP_DBG_OBJCOUNT */
 306
 307 #if defined CONFIG_SYSCTL
 308 void sctp_sysctl_register(void);
 309 void sctp_sysctl_unregister(void);
 310 int sctp_sysctl_net_register(struct net *net);
 311 void sctp_sysctl_net_unregister(struct net *net);
 312 #else
 313 static inline void sctp_sysctl_register(void) { return; }
 314 static inline void sctp_sysctl_unregister(void) { return; }
 315 static inline int sctp_sysctl_net_register(struct net *net) { return 0; }
 316 static inline void sctp_sysctl_net_unregister(struct net *net) { return; }
 317 #endif
 318
 319 /* Size of Supported Address Parameter for 'x' address types. */
 320 #define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16))
 321
 322 #if IS_ENABLED(CONFIG_IPV6)
 323
 324 void sctp_v6_pf_init(void);
 325 void sctp_v6_pf_exit(void);
 326 int sctp_v6_protosw_init(void);
 327 void sctp_v6_protosw_exit(void);
 328 int sctp_v6_add_protocol(void);
 329 void sctp_v6_del_protocol(void);
 330
 331 #else /* #ifdef defined(CONFIG_IPV6) */
 332
 333 static inline void sctp_v6_pf_init(void) { return; }
 334 static inline void sctp_v6_pf_exit(void) { return; }
 335 static inline int sctp_v6_protosw_init(void) { return 0; }
 336 static inline void sctp_v6_protosw_exit(void) { return; }
 337 static inline int sctp_v6_add_protocol(void) { return 0; }
 338 static inline void sctp_v6_del_protocol(void) { return; }
 339
 340 #endif /* #if defined(CONFIG_IPV6) */
 341
 342
 343 /* Map an association to an assoc_id. */
 344 static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc)
 345 {
 346         return asoc ? asoc->assoc_id : 0;
 347 }
 348
 349 /* Look up the association by its id.  */
 350 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);
 351
 352 int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp);
 353
 354 /* A macro to walk a list of skbs.  */
 355 #define sctp_skb_for_each(pos, head, tmp) \
 356         skb_queue_walk_safe(head, pos, tmp)
 357
 358 /* A helper to append an entire skb list (list) to another (head). */
 359 static inline void sctp_skb_list_tail(struct sk_buff_head *list,
 360                                       struct sk_buff_head *head)
 361 {
 362         unsigned long flags;
 363
 364         sctp_spin_lock_irqsave(&head->lock, flags);
 365         sctp_spin_lock(&list->lock);
 366
 367         skb_queue_splice_tail_init(list, head);
 368
 369         sctp_spin_unlock(&list->lock);
 370         sctp_spin_unlock_irqrestore(&head->lock, flags);
 371 }
 372
 373 /**
 374  *      sctp_list_dequeue - remove from the head of the queue
 375  *      @list: list to dequeue from
 376  *
 377  *      Remove the head of the list. The head item is
 378  *      returned or %NULL if the list is empty.
 379  */
 380
 381 static inline struct list_head *sctp_list_dequeue(struct list_head *list)
 382 {
 383         struct list_head *result = NULL;
 384
 385         if (list->next != list) {
 386                 result = list->next;
 387                 list->next = result->next;
 388                 list->next->prev = list;
 389                 INIT_LIST_HEAD(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  */
 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->sk_forward_alloc -= event->rmem_len;
 410 }
 411
 412 /* Tests if the list has one and only one entry. */
 413 static inline int sctp_list_single_entry(struct list_head *head)
 414 {
 415         return (head->next != head) && (head->next == head->prev);
 416 }
 417
 418 /* Generate a random jitter in the range of -50% ~ +50% of input RTO. */
 419 static inline __s32 sctp_jitter(__u32 rto)
 420 {
 421         static __u32 sctp_rand;
 422         __s32 ret;
 423
 424         /* Avoid divide by zero. */
 425         if (!rto)
 426                 rto = 1;
 427
 428         sctp_rand += jiffies;
 429         sctp_rand ^= (sctp_rand << 12);
 430         sctp_rand ^= (sctp_rand >> 20);
 431
 432         /* Choose random number from 0 to rto, then move to -50% ~ +50%
 433          * of rto.
 434          */
 435         ret = sctp_rand % rto - (rto >> 1);
 436         return ret;
 437 }
 438
 439 /* Break down data chunks at this point.  */
 440 static inline int sctp_frag_point(const struct sctp_association *asoc, int pmtu)
 441 {
 442         struct sctp_sock *sp = sctp_sk(asoc->base.sk);
 443         int frag = pmtu;
 444
 445         frag -= sp->pf->af->net_header_len;
 446         frag -= sizeof(struct sctphdr) + sizeof(struct sctp_data_chunk);
 447
 448         if (asoc->user_frag)
 449                 frag = min_t(int, frag, asoc->user_frag);
 450
 451         frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN);
 452
 453         return frag;
 454 }
 455
 456 static inline void sctp_assoc_pending_pmtu(struct sock *sk, struct sctp_association *asoc)
 457 {
 458
 459         sctp_assoc_sync_pmtu(sk, asoc);
 460         asoc->pmtu_pending = 0;
 461 }
 462
 463 /* Walk through a list of TLV parameters.  Don't trust the
 464  * individual parameter lengths and instead depend on
 465  * the chunk length to indicate when to stop.  Make sure
 466  * there is room for a param header too.
 467  */
 468 #define sctp_walk_params(pos, chunk, member)\
 469 _sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length), member)
 470
 471 #define _sctp_walk_params(pos, chunk, end, member)\
 472 for (pos.v = chunk->member;\
 473      pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\
 474      ntohs(pos.p->length) >= sizeof(sctp_paramhdr_t);\
 475      pos.v += WORD_ROUND(ntohs(pos.p->length)))
 476
 477 #define sctp_walk_errors(err, chunk_hdr)\
 478 _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
 479
 480 #define _sctp_walk_errors(err, chunk_hdr, end)\
 481 for (err = (sctp_errhdr_t *)((void *)chunk_hdr + \
 482             sizeof(sctp_chunkhdr_t));\
 483      (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\
 484      ntohs(err->length) >= sizeof(sctp_errhdr_t); \
 485      err = (sctp_errhdr_t *)((void *)err + WORD_ROUND(ntohs(err->length))))
 486
 487 #define sctp_walk_fwdtsn(pos, chunk)\
 488 _sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk))
 489
 490 #define _sctp_walk_fwdtsn(pos, chunk, end)\
 491 for (pos = chunk->subh.fwdtsn_hdr->skip;\
 492      (void *)pos <= (void *)chunk->subh.fwdtsn_hdr->skip + end - sizeof(struct sctp_fwdtsn_skip);\
 493      pos++)
 494
 495 /* Round an int up to the next multiple of 4.  */
 496 #define WORD_ROUND(s) (((s)+3)&~3)
 497
 498 /* External references. */
 499
 500 extern struct proto sctp_prot;
 501 extern struct proto sctpv6_prot;
 502 void sctp_put_port(struct sock *sk);
 503
 504 extern struct idr sctp_assocs_id;
 505 extern spinlock_t sctp_assocs_id_lock;
 506
 507 /* Static inline functions. */
 508
 509 /* Convert from an IP version number to an Address Family symbol.  */
 510 static inline int ipver2af(__u8 ipver)
 511 {
 512         switch (ipver) {
 513         case 4:
 514                 return  AF_INET;
 515         case 6:
 516                 return AF_INET6;
 517         default:
 518                 return 0;
 519         }
 520 }
 521
 522 /* Convert from an address parameter type to an address family.  */
 523 static inline int param_type2af(__be16 type)
 524 {
 525         switch (type) {
 526         case SCTP_PARAM_IPV4_ADDRESS:
 527                 return  AF_INET;
 528         case SCTP_PARAM_IPV6_ADDRESS:
 529                 return AF_INET6;
 530         default:
 531                 return 0;
 532         }
 533 }
 534
 535 /* Warning: The following hash functions assume a power of two 'size'. */
 536 /* This is the hash function for the SCTP port hash table. */
 537 static inline int sctp_phashfn(struct net *net, __u16 lport)
 538 {
 539         return (net_hash_mix(net) + lport) & (sctp_port_hashsize - 1);
 540 }
 541
 542 /* This is the hash function for the endpoint hash table. */
 543 static inline int sctp_ep_hashfn(struct net *net, __u16 lport)
 544 {
 545         return (net_hash_mix(net) + lport) & (sctp_ep_hashsize - 1);
 546 }
 547
 548 /* This is the hash function for the association hash table. */
 549 static inline int sctp_assoc_hashfn(struct net *net, __u16 lport, __u16 rport)
 550 {
 551         int h = (lport << 16) + rport + net_hash_mix(net);
 552         h ^= h>>8;
 553         return h & (sctp_assoc_hashsize - 1);
 554 }
 555
 556 /* This is the hash function for the association hash table.  This is
 557  * not used yet, but could be used as a better hash function when
 558  * we have a vtag.
 559  */
 560 static inline int sctp_vtag_hashfn(__u16 lport, __u16 rport, __u32 vtag)
 561 {
 562         int h = (lport << 16) + rport;
 563         h ^= vtag;
 564         return h & (sctp_assoc_hashsize - 1);
 565 }
 566
 567 #define sctp_for_each_hentry(epb, head) \
 568         hlist_for_each_entry(epb, head, node)
 569
 570 /* Is a socket of this style? */
 571 #define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
 572 static inline int __sctp_style(const struct sock *sk, sctp_socket_type_t style)
 573 {
 574         return sctp_sk(sk)->type == style;
 575 }
 576
 577 /* Is the association in this state? */
 578 #define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state))
 579 static inline int __sctp_state(const struct sctp_association *asoc,
 580                                sctp_state_t state)
 581 {
 582         return asoc->state == state;
 583 }
 584
 585 /* Is the socket in this state? */
 586 #define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state))
 587 static inline int __sctp_sstate(const struct sock *sk, sctp_sock_state_t state)
 588 {
 589         return sk->sk_state == state;
 590 }
 591
 592 /* Map v4-mapped v6 address back to v4 address */
 593 static inline void sctp_v6_map_v4(union sctp_addr *addr)
 594 {
 595         addr->v4.sin_family = AF_INET;
 596         addr->v4.sin_port = addr->v6.sin6_port;
 597         addr->v4.sin_addr.s_addr = addr->v6.sin6_addr.s6_addr32[3];
 598 }
 599
 600 /* Map v4 address to v4-mapped v6 address */
 601 static inline void sctp_v4_map_v6(union sctp_addr *addr)
 602 {
 603         addr->v6.sin6_family = AF_INET6;
 604         addr->v6.sin6_port = addr->v4.sin_port;
 605         addr->v6.sin6_addr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 606         addr->v6.sin6_addr.s6_addr32[0] = 0;
 607         addr->v6.sin6_addr.s6_addr32[1] = 0;
 608         addr->v6.sin6_addr.s6_addr32[2] = htonl(0x0000ffff);
 609 }
 610
 611 /* The cookie is always 0 since this is how it's used in the
 612  * pmtu code.
 613  */
 614 static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t)
 615 {
 616         if (t->dst && !dst_check(t->dst, 0)) {
 617                 dst_release(t->dst);
 618                 t->dst = NULL;
 619         }
 620
 621         return t->dst;
 622 }
 623
 624 #endif /* __net_sctp_h__ */