include/net/sctp/sctp.h

   1 /* SCTP kernel reference 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 reference Implementation
   8  *
   9  * The base lksctp header.
  10  *
  11  * The SCTP reference 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  * The SCTP reference 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
  66 #include <linux/config.h>
  67
  68 #ifdef TEST_FRAME
  69 #undef CONFIG_PROC_FS
  70 #undef CONFIG_SCTP_DBG_OBJCNT
  71 #undef CONFIG_SYSCTL
  72 #endif /* TEST_FRAME */
  73
  74 #include <linux/types.h>
  75 #include <linux/slab.h>
  76 #include <linux/in.h>
  77 #include <linux/tty.h>
  78 #include <linux/proc_fs.h>
  79 #include <linux/spinlock.h>
  80 #include <linux/jiffies.h>
  81 #include <linux/idr.h>
  82
  83 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  84 #include <net/ipv6.h>
  85 #include <net/ip6_route.h>
  86 #endif
  87
  88 #include <asm/uaccess.h>
  89 #include <asm/page.h>
  90 #include <net/sock.h>
  91 #include <net/snmp.h>
  92 #include <net/sctp/structs.h>
  93 #include <net/sctp/constants.h>
  94
  95
  96 /* Set SCTP_DEBUG flag via config if not already set. */
  97 #ifndef SCTP_DEBUG
  98 #ifdef CONFIG_SCTP_DBG_MSG
  99 #define SCTP_DEBUG      1
 100 #else
 101 #define SCTP_DEBUG      0
 102 #endif /* CONFIG_SCTP_DBG */
 103 #endif /* SCTP_DEBUG */
 104
 105 #ifdef CONFIG_IP_SCTP_MODULE
 106 #define SCTP_PROTOSW_FLAG 0
 107 #else /* static! */
 108 #define SCTP_PROTOSW_FLAG INET_PROTOSW_PERMANENT
 109 #endif
 110
 111
 112 /* Certain internal static functions need to be exported when
 113  * compiled into the test frame.
 114  */
 115 #ifndef SCTP_STATIC
 116 #define SCTP_STATIC static
 117 #endif
 118
 119 /*
 120  * Function declarations.
 121  */
 122
 123 /*
 124  * sctp/protocol.c
 125  */
 126 extern struct sock *sctp_get_ctl_sock(void);
 127 extern int sctp_copy_local_addr_list(struct sctp_bind_addr *,
 128                                      sctp_scope_t, gfp_t gfp,
 129                                      int flags);
 130 extern struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
 131 extern int sctp_register_pf(struct sctp_pf *, sa_family_t);
 132
 133 /*
 134  * sctp/socket.c
 135  */
 136 int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
 137 int sctp_inet_listen(struct socket *sock, int backlog);
 138 void sctp_write_space(struct sock *sk);
 139 unsigned int sctp_poll(struct file *file, struct socket *sock,
 140                 poll_table *wait);
 141
 142 /*
 143  * sctp/primitive.c
 144  */
 145 int sctp_primitive_ASSOCIATE(struct sctp_association *, void *arg);
 146 int sctp_primitive_SHUTDOWN(struct sctp_association *, void *arg);
 147 int sctp_primitive_ABORT(struct sctp_association *, void *arg);
 148 int sctp_primitive_SEND(struct sctp_association *, void *arg);
 149 int sctp_primitive_REQUESTHEARTBEAT(struct sctp_association *, void *arg);
 150 int sctp_primitive_ASCONF(struct sctp_association *, void *arg);
 151
 152 /*
 153  * sctp/crc32c.c
 154  */
 155 __u32 sctp_start_cksum(__u8 *ptr, __u16 count);
 156 __u32 sctp_update_cksum(__u8 *ptr, __u16 count, __u32 cksum);
 157 __u32 sctp_end_cksum(__u32 cksum);
 158 __u32 sctp_update_copy_cksum(__u8 *, __u8 *, __u16 count, __u32 cksum);
 159
 160 /*
 161  * sctp/input.c
 162  */
 163 int sctp_rcv(struct sk_buff *skb);
 164 void sctp_v4_err(struct sk_buff *skb, u32 info);
 165 void sctp_hash_established(struct sctp_association *);
 166 void sctp_unhash_established(struct sctp_association *);
 167 void sctp_hash_endpoint(struct sctp_endpoint *);
 168 void sctp_unhash_endpoint(struct sctp_endpoint *);
 169 struct sock *sctp_err_lookup(int family, struct sk_buff *,
 170                              struct sctphdr *, struct sctp_association **,
 171                              struct sctp_transport **);
 172 void sctp_err_finish(struct sock *, struct sctp_association *);
 173 void sctp_icmp_frag_needed(struct sock *, struct sctp_association *,
 174                            struct sctp_transport *t, __u32 pmtu);
 175 void sctp_icmp_proto_unreachable(struct sock *sk,
 176                                  struct sctp_association *asoc,
 177                                  struct sctp_transport *t);
 178
 179 /*
 180  *  Section:  Macros, externs, and inlines
 181  */
 182
 183
 184 #ifdef TEST_FRAME
 185 #include <test_frame.h>
 186 #else
 187
 188 /* spin lock wrappers. */
 189 #define sctp_spin_lock_irqsave(lock, flags) spin_lock_irqsave(lock, flags)
 190 #define sctp_spin_unlock_irqrestore(lock, flags)  \
 191        spin_unlock_irqrestore(lock, flags)
 192 #define sctp_local_bh_disable() local_bh_disable()
 193 #define sctp_local_bh_enable()  local_bh_enable()
 194 #define sctp_spin_lock(lock)    spin_lock(lock)
 195 #define sctp_spin_unlock(lock)  spin_unlock(lock)
 196 #define sctp_write_lock(lock)   write_lock(lock)
 197 #define sctp_write_unlock(lock) write_unlock(lock)
 198 #define sctp_read_lock(lock)    read_lock(lock)
 199 #define sctp_read_unlock(lock)  read_unlock(lock)
 200
 201 /* sock lock wrappers. */
 202 #define sctp_lock_sock(sk)       lock_sock(sk)
 203 #define sctp_release_sock(sk)    release_sock(sk)
 204 #define sctp_bh_lock_sock(sk)    bh_lock_sock(sk)
 205 #define sctp_bh_unlock_sock(sk)  bh_unlock_sock(sk)
 206 #define SCTP_SOCK_SLEEP_PRE(sk)  SOCK_SLEEP_PRE(sk)
 207 #define SCTP_SOCK_SLEEP_POST(sk) SOCK_SLEEP_POST(sk)
 208
 209 /* SCTP SNMP MIB stats handlers */
 210 DECLARE_SNMP_STAT(struct sctp_mib, sctp_statistics);
 211 #define SCTP_INC_STATS(field)      SNMP_INC_STATS(sctp_statistics, field)
 212 #define SCTP_INC_STATS_BH(field)   SNMP_INC_STATS_BH(sctp_statistics, field)
 213 #define SCTP_INC_STATS_USER(field) SNMP_INC_STATS_USER(sctp_statistics, field)
 214 #define SCTP_DEC_STATS(field)      SNMP_DEC_STATS(sctp_statistics, field)
 215
 216 #endif /* !TEST_FRAME */
 217
 218
 219 /* Print debugging messages.  */
 220 #if SCTP_DEBUG
 221 extern int sctp_debug_flag;
 222 #define SCTP_DEBUG_PRINTK(whatever...) \
 223         ((void) (sctp_debug_flag && printk(KERN_DEBUG whatever)))
 224 #define SCTP_DEBUG_PRINTK_IPADDR(lead, trail, leadparm, saddr, otherparms...) \
 225         if (sctp_debug_flag) { \
 226                 if (saddr->sa.sa_family == AF_INET6) { \
 227                         printk(KERN_DEBUG \
 228                                lead "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x" trail, \
 229                                leadparm, \
 230                                NIP6(saddr->v6.sin6_addr), \
 231                                otherparms); \
 232                 } else { \
 233                         printk(KERN_DEBUG \
 234                                lead "%u.%u.%u.%u" trail, \
 235                                leadparm, \
 236                                NIPQUAD(saddr->v4.sin_addr.s_addr), \
 237                                otherparms); \
 238                 } \
 239         }
 240 #define SCTP_ENABLE_DEBUG { sctp_debug_flag = 1; }
 241 #define SCTP_DISABLE_DEBUG { sctp_debug_flag = 0; }
 242
 243 #define SCTP_ASSERT(expr, str, func) \
 244         if (!(expr)) { \
 245                 SCTP_DEBUG_PRINTK("Assertion Failed: %s(%s) at %s:%s:%d\n", \
 246                         str, (#expr), __FILE__, __FUNCTION__, __LINE__); \
 247                 func; \
 248         }
 249
 250 #else   /* SCTP_DEBUG */
 251
 252 #define SCTP_DEBUG_PRINTK(whatever...)
 253 #define SCTP_DEBUG_PRINTK_IPADDR(whatever...)
 254 #define SCTP_ENABLE_DEBUG
 255 #define SCTP_DISABLE_DEBUG
 256 #define SCTP_ASSERT(expr, str, func)
 257
 258 #endif /* SCTP_DEBUG */
 259
 260
 261 /*
 262  * Macros for keeping a global reference of object allocations.
 263  */
 264 #ifdef CONFIG_SCTP_DBG_OBJCNT
 265
 266 extern atomic_t sctp_dbg_objcnt_sock;
 267 extern atomic_t sctp_dbg_objcnt_ep;
 268 extern atomic_t sctp_dbg_objcnt_assoc;
 269 extern atomic_t sctp_dbg_objcnt_transport;
 270 extern atomic_t sctp_dbg_objcnt_chunk;
 271 extern atomic_t sctp_dbg_objcnt_bind_addr;
 272 extern atomic_t sctp_dbg_objcnt_bind_bucket;
 273 extern atomic_t sctp_dbg_objcnt_addr;
 274 extern atomic_t sctp_dbg_objcnt_ssnmap;
 275 extern atomic_t sctp_dbg_objcnt_datamsg;
 276
 277 /* Macros to atomically increment/decrement objcnt counters.  */
 278 #define SCTP_DBG_OBJCNT_INC(name) \
 279 atomic_inc(&sctp_dbg_objcnt_## name)
 280 #define SCTP_DBG_OBJCNT_DEC(name) \
 281 atomic_dec(&sctp_dbg_objcnt_## name)
 282 #define SCTP_DBG_OBJCNT(name) \
 283 atomic_t sctp_dbg_objcnt_## name = ATOMIC_INIT(0)
 284
 285 /* Macro to help create new entries in in the global array of
 286  * objcnt counters.
 287  */
 288 #define SCTP_DBG_OBJCNT_ENTRY(name) \
 289 {.label= #name, .counter= &sctp_dbg_objcnt_## name}
 290
 291 void sctp_dbg_objcnt_init(void);
 292 void sctp_dbg_objcnt_exit(void);
 293
 294 #else
 295
 296 #define SCTP_DBG_OBJCNT_INC(name)
 297 #define SCTP_DBG_OBJCNT_DEC(name)
 298
 299 static inline void sctp_dbg_objcnt_init(void) { return; }
 300 static inline void sctp_dbg_objcnt_exit(void) { return; }
 301
 302 #endif /* CONFIG_SCTP_DBG_OBJCOUNT */
 303
 304 #if defined CONFIG_SYSCTL
 305 void sctp_sysctl_register(void);
 306 void sctp_sysctl_unregister(void);
 307 #else
 308 static inline void sctp_sysctl_register(void) { return; }
 309 static inline void sctp_sysctl_unregister(void) { return; }
 310 static inline int sctp_sysctl_jiffies_ms(ctl_table *table, int __user *name, int nlen,
 311                 void __user *oldval, size_t __user *oldlenp,
 312                 void __user *newval, size_t newlen, void **context) {
 313         return -ENOSYS;
 314 }
 315 #endif
 316
 317 /* Size of Supported Address Parameter for 'x' address types. */
 318 #define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16))
 319
 320 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 321
 322 int sctp_v6_init(void);
 323 void sctp_v6_exit(void);
 324
 325 #else /* #ifdef defined(CONFIG_IPV6) */
 326
 327 static inline int sctp_v6_init(void) { return 0; }
 328 static inline void sctp_v6_exit(void) { return; }
 329
 330 #endif /* #if defined(CONFIG_IPV6) */
 331
 332 /* Some wrappers, in case crypto not available. */
 333 #if defined (CONFIG_CRYPTO_HMAC)
 334 #define sctp_crypto_alloc_tfm crypto_alloc_tfm
 335 #define sctp_crypto_free_tfm crypto_free_tfm
 336 #define sctp_crypto_hmac crypto_hmac
 337 #else
 338 #define sctp_crypto_alloc_tfm(x...) NULL
 339 #define sctp_crypto_free_tfm(x...)
 340 #define sctp_crypto_hmac(x...)
 341 #endif
 342
 343
 344 /* Map an association to an assoc_id. */
 345 static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc)
 346 {
 347         return (asoc?asoc->assoc_id:0);
 348 }
 349
 350 /* Look up the association by its id.  */
 351 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);
 352
 353
 354 /* A macro to walk a list of skbs.  */
 355 #define sctp_skb_for_each(pos, head, tmp) \
 356 for (pos = (head)->next;\
 357      tmp = (pos)->next, pos != ((struct sk_buff *)(head));\
 358      pos = tmp)
 359
 360
 361 /* A helper to append an entire skb list (list) to another (head). */
 362 static inline void sctp_skb_list_tail(struct sk_buff_head *list,
 363                                       struct sk_buff_head *head)
 364 {
 365         unsigned long flags;
 366
 367         sctp_spin_lock_irqsave(&head->lock, flags);
 368         sctp_spin_lock(&list->lock);
 369
 370         list_splice((struct list_head *)list, (struct list_head *)head->prev);
 371
 372         head->qlen += list->qlen;
 373         list->qlen = 0;
 374
 375         sctp_spin_unlock(&list->lock);
 376         sctp_spin_unlock_irqrestore(&head->lock, flags);
 377 }
 378
 379 /**
 380  *      sctp_list_dequeue - remove from the head of the queue
 381  *      @list: list to dequeue from
 382  *
 383  *      Remove the head of the list. The head item is
 384  *      returned or %NULL if the list is empty.
 385  */
 386
 387 static inline struct list_head *sctp_list_dequeue(struct list_head *list)
 388 {
 389         struct list_head *result = NULL;
 390
 391         if (list->next != list) {
 392                 result = list->next;
 393                 list->next = result->next;
 394                 list->next->prev = list;
 395                 INIT_LIST_HEAD(result);
 396         }
 397         return result;
 398 }
 399
 400 /* Tests if the list has one and only one entry. */
 401 static inline int sctp_list_single_entry(struct list_head *head)
 402 {
 403         return ((head->next != head) && (head->next == head->prev));
 404 }
 405
 406 /* Calculate the size (in bytes) occupied by the data of an iovec.  */
 407 static inline size_t get_user_iov_size(struct iovec *iov, int iovlen)
 408 {
 409         size_t retval = 0;
 410
 411         for (; iovlen > 0; --iovlen) {
 412                 retval += iov->iov_len;
 413                 iov++;
 414         }
 415
 416         return retval;
 417 }
 418
 419 /* Generate a random jitter in the range of -50% ~ +50% of input RTO. */
 420 static inline __s32 sctp_jitter(__u32 rto)
 421 {
 422         static __u32 sctp_rand;
 423         __s32 ret;
 424
 425         /* Avoid divide by zero. */
 426         if (!rto)
 427                 rto = 1;
 428
 429         sctp_rand += jiffies;
 430         sctp_rand ^= (sctp_rand << 12);
 431         sctp_rand ^= (sctp_rand >> 20);
 432
 433         /* Choose random number from 0 to rto, then move to -50% ~ +50%
 434          * of rto.
 435          */
 436         ret = sctp_rand % rto - (rto >> 1);
 437         return ret;
 438 }
 439
 440 /* Break down data chunks at this point.  */
 441 static inline int sctp_frag_point(const struct sctp_sock *sp, int pmtu)
 442 {
 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 (sp->user_frag)
 449                 frag = min_t(int, frag, sp->user_frag);
 450
 451         frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN);
 452
 453         return frag;
 454 }
 455
 456 /* Walk through a list of TLV parameters.  Don't trust the
 457  * individual parameter lengths and instead depend on
 458  * the chunk length to indicate when to stop.  Make sure
 459  * there is room for a param header too.
 460  */
 461 #define sctp_walk_params(pos, chunk, member)\
 462 _sctp_walk_params((pos), (chunk), WORD_ROUND(ntohs((chunk)->chunk_hdr.length)), member)
 463
 464 #define _sctp_walk_params(pos, chunk, end, member)\
 465 for (pos.v = chunk->member;\
 466      pos.v <= (void *)chunk + end - sizeof(sctp_paramhdr_t) &&\
 467      pos.v <= (void *)chunk + end - WORD_ROUND(ntohs(pos.p->length)) &&\
 468      ntohs(pos.p->length) >= sizeof(sctp_paramhdr_t);\
 469      pos.v += WORD_ROUND(ntohs(pos.p->length)))
 470
 471 #define sctp_walk_errors(err, chunk_hdr)\
 472 _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
 473
 474 #define _sctp_walk_errors(err, chunk_hdr, end)\
 475 for (err = (sctp_errhdr_t *)((void *)chunk_hdr + \
 476             sizeof(sctp_chunkhdr_t));\
 477      (void *)err <= (void *)chunk_hdr + end - sizeof(sctp_errhdr_t) &&\
 478      (void *)err <= (void *)chunk_hdr + end - WORD_ROUND(ntohs(err->length)) &&\
 479      ntohs(err->length) >= sizeof(sctp_errhdr_t); \
 480      err = (sctp_errhdr_t *)((void *)err + WORD_ROUND(ntohs(err->length))))
 481
 482 #define sctp_walk_fwdtsn(pos, chunk)\
 483 _sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk))
 484
 485 #define _sctp_walk_fwdtsn(pos, chunk, end)\
 486 for (pos = chunk->subh.fwdtsn_hdr->skip;\
 487      (void *)pos <= (void *)chunk->subh.fwdtsn_hdr->skip + end - sizeof(struct sctp_fwdtsn_skip);\
 488      pos++)
 489
 490 /* Round an int up to the next multiple of 4.  */
 491 #define WORD_ROUND(s) (((s)+3)&~3)
 492
 493 /* Make a new instance of type.  */
 494 #define t_new(type, flags)      (type *)kmalloc(sizeof(type), flags)
 495
 496 /* Compare two timevals.  */
 497 #define tv_lt(s, t) \
 498    (s.tv_sec < t.tv_sec || (s.tv_sec == t.tv_sec && s.tv_usec < t.tv_usec))
 499
 500 /* Add tv1 to tv2. */
 501 #define TIMEVAL_ADD(tv1, tv2) \
 502 ({ \
 503         suseconds_t usecs = (tv2).tv_usec + (tv1).tv_usec; \
 504         time_t secs = (tv2).tv_sec + (tv1).tv_sec; \
 505 \
 506         if (usecs >= 1000000) { \
 507                 usecs -= 1000000; \
 508                 secs++; \
 509         } \
 510         (tv2).tv_sec = secs; \
 511         (tv2).tv_usec = usecs; \
 512 })
 513
 514 /* External references. */
 515
 516 extern struct proto sctp_prot;
 517 extern struct proto sctpv6_prot;
 518 extern struct proc_dir_entry *proc_net_sctp;
 519 void sctp_put_port(struct sock *sk);
 520
 521 extern struct idr sctp_assocs_id;
 522 extern spinlock_t sctp_assocs_id_lock;
 523
 524 /* Static inline functions. */
 525
 526 /* Convert from an IP version number to an Address Family symbol.  */
 527 static inline int ipver2af(__u8 ipver)
 528 {
 529         switch (ipver) {
 530         case 4:
 531                 return  AF_INET;
 532         case 6:
 533                 return AF_INET6;
 534         default:
 535                 return 0;
 536         };
 537 }
 538
 539 /* Convert from an address parameter type to an address family.  */
 540 static inline int param_type2af(__u16 type)
 541 {
 542         switch (type) {
 543         case SCTP_PARAM_IPV4_ADDRESS:
 544                 return  AF_INET;
 545         case SCTP_PARAM_IPV6_ADDRESS:
 546                 return AF_INET6;
 547         default:
 548                 return 0;
 549         };
 550 }
 551
 552 /* Perform some sanity checks. */
 553 static inline int sctp_sanity_check(void)
 554 {
 555         SCTP_ASSERT(sizeof(struct sctp_ulpevent) <=
 556                     sizeof(((struct sk_buff *)0)->cb),
 557                     "SCTP: ulpevent does not fit in skb!\n", return 0);
 558
 559         return 1;
 560 }
 561
 562 /* Warning: The following hash functions assume a power of two 'size'. */
 563 /* This is the hash function for the SCTP port hash table. */
 564 static inline int sctp_phashfn(__u16 lport)
 565 {
 566         return (lport & (sctp_port_hashsize - 1));
 567 }
 568
 569 /* This is the hash function for the endpoint hash table. */
 570 static inline int sctp_ep_hashfn(__u16 lport)
 571 {
 572         return (lport & (sctp_ep_hashsize - 1));
 573 }
 574
 575 /* This is the hash function for the association hash table. */
 576 static inline int sctp_assoc_hashfn(__u16 lport, __u16 rport)
 577 {
 578         int h = (lport << 16) + rport;
 579         h ^= h>>8;
 580         return (h & (sctp_assoc_hashsize - 1));
 581 }
 582
 583 /* This is the hash function for the association hash table.  This is
 584  * not used yet, but could be used as a better hash function when
 585  * we have a vtag.
 586  */
 587 static inline int sctp_vtag_hashfn(__u16 lport, __u16 rport, __u32 vtag)
 588 {
 589         int h = (lport << 16) + rport;
 590         h ^= vtag;
 591         return (h & (sctp_assoc_hashsize-1));
 592 }
 593
 594 /* Is a socket of this style? */
 595 #define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
 596 static inline int __sctp_style(const struct sock *sk, sctp_socket_type_t style)
 597 {
 598         return sctp_sk(sk)->type == style;
 599 }
 600
 601 /* Is the association in this state? */
 602 #define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state))
 603 static inline int __sctp_state(const struct sctp_association *asoc,
 604                                sctp_state_t state)
 605 {
 606         return asoc->state == state;
 607 }
 608
 609 /* Is the socket in this state? */
 610 #define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state))
 611 static inline int __sctp_sstate(const struct sock *sk, sctp_sock_state_t state)
 612 {
 613         return sk->sk_state == state;
 614 }
 615
 616 /* Map v4-mapped v6 address back to v4 address */
 617 static inline void sctp_v6_map_v4(union sctp_addr *addr)
 618 {
 619         addr->v4.sin_family = AF_INET;
 620         addr->v4.sin_port = addr->v6.sin6_port;
 621         addr->v4.sin_addr.s_addr = addr->v6.sin6_addr.s6_addr32[3];
 622 }
 623
 624 /* Map v4 address to v4-mapped v6 address */
 625 static inline void sctp_v4_map_v6(union sctp_addr *addr)
 626 {
 627         addr->v6.sin6_family = AF_INET6;
 628         addr->v6.sin6_port = addr->v4.sin_port;
 629         addr->v6.sin6_addr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 630         addr->v6.sin6_addr.s6_addr32[0] = 0;
 631         addr->v6.sin6_addr.s6_addr32[1] = 0;
 632         addr->v6.sin6_addr.s6_addr32[2] = htonl(0x0000ffff);
 633 }
 634
 635 #endif /* __net_sctp_h__ */