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
  87 /* Set SCTP_DEBUG flag via config if not already set. */
  88 #ifndef SCTP_DEBUG
  89 #ifdef CONFIG_SCTP_DBG_MSG
  90 #define SCTP_DEBUG      1
  91 #else
  92 #define SCTP_DEBUG      0
  93 #endif /* CONFIG_SCTP_DBG */
  94 #endif /* SCTP_DEBUG */
  95
  96 #ifdef CONFIG_IP_SCTP_MODULE
  97 #define SCTP_PROTOSW_FLAG 0
  98 #else /* static! */
  99 #define SCTP_PROTOSW_FLAG INET_PROTOSW_PERMANENT
 100 #endif
 101
 102
 103 /* Certain internal static functions need to be exported when
 104  * compiled into the test frame.
 105  */
 106 #ifndef SCTP_STATIC
 107 #define SCTP_STATIC static
 108 #endif
 109
 110 /*
 111  * Function declarations.
 112  */
 113
 114 /*
 115  * sctp/protocol.c
 116  */
 117 extern struct sock *sctp_get_ctl_sock(void);
 118 extern int sctp_copy_local_addr_list(struct sctp_bind_addr *,
 119                                      sctp_scope_t, gfp_t gfp,
 120                                      int flags);
 121 extern struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
 122 extern int sctp_register_pf(struct sctp_pf *, sa_family_t);
 123 extern void sctp_addr_wq_mgmt(struct sctp_sockaddr_entry *, int);
 124
 125 /*
 126  * sctp/socket.c
 127  */
 128 int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
 129 int sctp_inet_listen(struct socket *sock, int backlog);
 130 void sctp_write_space(struct sock *sk);
 131 void sctp_data_ready(struct sock *sk, int len);
 132 unsigned int sctp_poll(struct file *file, struct socket *sock,
 133                 poll_table *wait);
 134 void sctp_sock_rfree(struct sk_buff *skb);
 135 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
 136                     struct sctp_association *asoc);
 137 extern struct percpu_counter sctp_sockets_allocated;
 138 extern int sctp_asconf_mgmt(struct sctp_sock *, struct sctp_sockaddr_entry *);
 139
 140 /*
 141  * sctp/primitive.c
 142  */
 143 int sctp_primitive_ASSOCIATE(struct sctp_association *, void *arg);
 144 int sctp_primitive_SHUTDOWN(struct sctp_association *, void *arg);
 145 int sctp_primitive_ABORT(struct sctp_association *, void *arg);
 146 int sctp_primitive_SEND(struct sctp_association *, void *arg);
 147 int sctp_primitive_REQUESTHEARTBEAT(struct sctp_association *, void *arg);
 148 int sctp_primitive_ASCONF(struct sctp_association *, 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_established(struct sctp_association *);
 156 void sctp_unhash_established(struct sctp_association *);
 157 void sctp_hash_endpoint(struct sctp_endpoint *);
 158 void sctp_unhash_endpoint(struct sctp_endpoint *);
 159 struct sock *sctp_err_lookup(int family, struct sk_buff *,
 160                              struct sctphdr *, struct sctp_association **,
 161                              struct sctp_transport **);
 162 void sctp_err_finish(struct sock *, struct sctp_association *);
 163 void sctp_icmp_frag_needed(struct sock *, struct sctp_association *,
 164                            struct sctp_transport *t, __u32 pmtu);
 165 void sctp_icmp_redirect(struct sock *, struct sctp_transport *,
 166                         struct sk_buff *);
 167 void sctp_icmp_proto_unreachable(struct sock *sk,
 168                                  struct sctp_association *asoc,
 169                                  struct sctp_transport *t);
 170 void sctp_backlog_migrate(struct sctp_association *assoc,
 171                           struct sock *oldsk, struct sock *newsk);
 172
 173 /*
 174  * sctp/proc.c
 175  */
 176 int sctp_snmp_proc_init(void);
 177 void sctp_snmp_proc_exit(void);
 178 int sctp_eps_proc_init(void);
 179 void sctp_eps_proc_exit(void);
 180 int sctp_assocs_proc_init(void);
 181 void sctp_assocs_proc_exit(void);
 182 int sctp_remaddr_proc_init(void);
 183 void sctp_remaddr_proc_exit(void);
 184
 185
 186 /*
 187  * Module global variables
 188  */
 189
 190  /*
 191   * sctp/protocol.c
 192   */
 193 extern struct kmem_cache *sctp_chunk_cachep __read_mostly;
 194 extern struct kmem_cache *sctp_bucket_cachep __read_mostly;
 195
 196 /*
 197  *  Section:  Macros, externs, and inlines
 198  */
 199
 200
 201 #ifdef TEST_FRAME
 202 #include <test_frame.h>
 203 #else
 204
 205 /* spin lock wrappers. */
 206 #define sctp_spin_lock_irqsave(lock, flags) spin_lock_irqsave(lock, flags)
 207 #define sctp_spin_unlock_irqrestore(lock, flags)  \
 208        spin_unlock_irqrestore(lock, flags)
 209 #define sctp_local_bh_disable() local_bh_disable()
 210 #define sctp_local_bh_enable()  local_bh_enable()
 211 #define sctp_spin_lock(lock)    spin_lock(lock)
 212 #define sctp_spin_unlock(lock)  spin_unlock(lock)
 213 #define sctp_write_lock(lock)   write_lock(lock)
 214 #define sctp_write_unlock(lock) write_unlock(lock)
 215 #define sctp_read_lock(lock)    read_lock(lock)
 216 #define sctp_read_unlock(lock)  read_unlock(lock)
 217
 218 /* sock lock wrappers. */
 219 #define sctp_lock_sock(sk)       lock_sock(sk)
 220 #define sctp_release_sock(sk)    release_sock(sk)
 221 #define sctp_bh_lock_sock(sk)    bh_lock_sock(sk)
 222 #define sctp_bh_unlock_sock(sk)  bh_unlock_sock(sk)
 223
 224 /* SCTP SNMP MIB stats handlers */
 225 DECLARE_SNMP_STAT(struct sctp_mib, sctp_statistics);
 226 #define SCTP_INC_STATS(field)      SNMP_INC_STATS(sctp_statistics, field)
 227 #define SCTP_INC_STATS_BH(field)   SNMP_INC_STATS_BH(sctp_statistics, field)
 228 #define SCTP_INC_STATS_USER(field) SNMP_INC_STATS_USER(sctp_statistics, field)
 229 #define SCTP_DEC_STATS(field)      SNMP_DEC_STATS(sctp_statistics, field)
 230
 231 #endif /* !TEST_FRAME */
 232
 233 /* sctp mib definitions */
 234 enum {
 235         SCTP_MIB_NUM = 0,
 236         SCTP_MIB_CURRESTAB,                     /* CurrEstab */
 237         SCTP_MIB_ACTIVEESTABS,                  /* ActiveEstabs */
 238         SCTP_MIB_PASSIVEESTABS,                 /* PassiveEstabs */
 239         SCTP_MIB_ABORTEDS,                      /* Aborteds */
 240         SCTP_MIB_SHUTDOWNS,                     /* Shutdowns */
 241         SCTP_MIB_OUTOFBLUES,                    /* OutOfBlues */
 242         SCTP_MIB_CHECKSUMERRORS,                /* ChecksumErrors */
 243         SCTP_MIB_OUTCTRLCHUNKS,                 /* OutCtrlChunks */
 244         SCTP_MIB_OUTORDERCHUNKS,                /* OutOrderChunks */
 245         SCTP_MIB_OUTUNORDERCHUNKS,              /* OutUnorderChunks */
 246         SCTP_MIB_INCTRLCHUNKS,                  /* InCtrlChunks */
 247         SCTP_MIB_INORDERCHUNKS,                 /* InOrderChunks */
 248         SCTP_MIB_INUNORDERCHUNKS,               /* InUnorderChunks */
 249         SCTP_MIB_FRAGUSRMSGS,                   /* FragUsrMsgs */
 250         SCTP_MIB_REASMUSRMSGS,                  /* ReasmUsrMsgs */
 251         SCTP_MIB_OUTSCTPPACKS,                  /* OutSCTPPacks */
 252         SCTP_MIB_INSCTPPACKS,                   /* InSCTPPacks */
 253         SCTP_MIB_T1_INIT_EXPIREDS,
 254         SCTP_MIB_T1_COOKIE_EXPIREDS,
 255         SCTP_MIB_T2_SHUTDOWN_EXPIREDS,
 256         SCTP_MIB_T3_RTX_EXPIREDS,
 257         SCTP_MIB_T4_RTO_EXPIREDS,
 258         SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS,
 259         SCTP_MIB_DELAY_SACK_EXPIREDS,
 260         SCTP_MIB_AUTOCLOSE_EXPIREDS,
 261         SCTP_MIB_T1_RETRANSMITS,
 262         SCTP_MIB_T3_RETRANSMITS,
 263         SCTP_MIB_PMTUD_RETRANSMITS,
 264         SCTP_MIB_FAST_RETRANSMITS,
 265         SCTP_MIB_IN_PKT_SOFTIRQ,
 266         SCTP_MIB_IN_PKT_BACKLOG,
 267         SCTP_MIB_IN_PKT_DISCARDS,
 268         SCTP_MIB_IN_DATA_CHUNK_DISCARDS,
 269         __SCTP_MIB_MAX
 270 };
 271
 272 #define SCTP_MIB_MAX    __SCTP_MIB_MAX
 273 struct sctp_mib {
 274         unsigned long   mibs[SCTP_MIB_MAX];
 275 };
 276
 277
 278 /* Print debugging messages.  */
 279 #if SCTP_DEBUG
 280 extern int sctp_debug_flag;
 281 #define SCTP_DEBUG_PRINTK(fmt, args...)                 \
 282 do {                                                    \
 283         if (sctp_debug_flag)                            \
 284                 printk(KERN_DEBUG pr_fmt(fmt), ##args); \
 285 } while (0)
 286 #define SCTP_DEBUG_PRINTK_CONT(fmt, args...)            \
 287 do {                                                    \
 288         if (sctp_debug_flag)                            \
 289                 pr_cont(fmt, ##args);                   \
 290 } while (0)
 291 #define SCTP_DEBUG_PRINTK_IPADDR(fmt_lead, fmt_trail,                   \
 292                                  args_lead, addr, args_trail...)        \
 293 do {                                                                    \
 294         const union sctp_addr *_addr = (addr);                          \
 295         if (sctp_debug_flag) {                                          \
 296                 if (_addr->sa.sa_family == AF_INET6) {                  \
 297                         printk(KERN_DEBUG                               \
 298                                pr_fmt(fmt_lead "%pI6" fmt_trail),       \
 299                                args_lead,                               \
 300                                &_addr->v6.sin6_addr,                    \
 301                                args_trail);                             \
 302                 } else {                                                \
 303                         printk(KERN_DEBUG                               \
 304                                pr_fmt(fmt_lead "%pI4" fmt_trail),       \
 305                                args_lead,                               \
 306                                &_addr->v4.sin_addr.s_addr,              \
 307                                args_trail);                             \
 308                 }                                                       \
 309         }                                                               \
 310 } while (0)
 311 #define SCTP_ENABLE_DEBUG { sctp_debug_flag = 1; }
 312 #define SCTP_DISABLE_DEBUG { sctp_debug_flag = 0; }
 313
 314 #define SCTP_ASSERT(expr, str, func) \
 315         if (!(expr)) { \
 316                 SCTP_DEBUG_PRINTK("Assertion Failed: %s(%s) at %s:%s:%d\n", \
 317                         str, (#expr), __FILE__, __func__, __LINE__); \
 318                 func; \
 319         }
 320
 321 #else   /* SCTP_DEBUG */
 322
 323 #define SCTP_DEBUG_PRINTK(whatever...)
 324 #define SCTP_DEBUG_PRINTK_CONT(fmt, args...)
 325 #define SCTP_DEBUG_PRINTK_IPADDR(whatever...)
 326 #define SCTP_ENABLE_DEBUG
 327 #define SCTP_DISABLE_DEBUG
 328 #define SCTP_ASSERT(expr, str, func)
 329
 330 #endif /* SCTP_DEBUG */
 331
 332
 333 /*
 334  * Macros for keeping a global reference of object allocations.
 335  */
 336 #ifdef CONFIG_SCTP_DBG_OBJCNT
 337
 338 extern atomic_t sctp_dbg_objcnt_sock;
 339 extern atomic_t sctp_dbg_objcnt_ep;
 340 extern atomic_t sctp_dbg_objcnt_assoc;
 341 extern atomic_t sctp_dbg_objcnt_transport;
 342 extern atomic_t sctp_dbg_objcnt_chunk;
 343 extern atomic_t sctp_dbg_objcnt_bind_addr;
 344 extern atomic_t sctp_dbg_objcnt_bind_bucket;
 345 extern atomic_t sctp_dbg_objcnt_addr;
 346 extern atomic_t sctp_dbg_objcnt_ssnmap;
 347 extern atomic_t sctp_dbg_objcnt_datamsg;
 348 extern atomic_t sctp_dbg_objcnt_keys;
 349
 350 /* Macros to atomically increment/decrement objcnt counters.  */
 351 #define SCTP_DBG_OBJCNT_INC(name) \
 352 atomic_inc(&sctp_dbg_objcnt_## name)
 353 #define SCTP_DBG_OBJCNT_DEC(name) \
 354 atomic_dec(&sctp_dbg_objcnt_## name)
 355 #define SCTP_DBG_OBJCNT(name) \
 356 atomic_t sctp_dbg_objcnt_## name = ATOMIC_INIT(0)
 357
 358 /* Macro to help create new entries in in the global array of
 359  * objcnt counters.
 360  */
 361 #define SCTP_DBG_OBJCNT_ENTRY(name) \
 362 {.label= #name, .counter= &sctp_dbg_objcnt_## name}
 363
 364 void sctp_dbg_objcnt_init(void);
 365 void sctp_dbg_objcnt_exit(void);
 366
 367 #else
 368
 369 #define SCTP_DBG_OBJCNT_INC(name)
 370 #define SCTP_DBG_OBJCNT_DEC(name)
 371
 372 static inline void sctp_dbg_objcnt_init(void) { return; }
 373 static inline void sctp_dbg_objcnt_exit(void) { return; }
 374
 375 #endif /* CONFIG_SCTP_DBG_OBJCOUNT */
 376
 377 #if defined CONFIG_SYSCTL
 378 void sctp_sysctl_register(void);
 379 void sctp_sysctl_unregister(void);
 380 #else
 381 static inline void sctp_sysctl_register(void) { return; }
 382 static inline void sctp_sysctl_unregister(void) { return; }
 383 #endif
 384
 385 /* Size of Supported Address Parameter for 'x' address types. */
 386 #define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16))
 387
 388 #if IS_ENABLED(CONFIG_IPV6)
 389
 390 void sctp_v6_pf_init(void);
 391 void sctp_v6_pf_exit(void);
 392 int sctp_v6_protosw_init(void);
 393 void sctp_v6_protosw_exit(void);
 394 int sctp_v6_add_protocol(void);
 395 void sctp_v6_del_protocol(void);
 396
 397 #else /* #ifdef defined(CONFIG_IPV6) */
 398
 399 static inline void sctp_v6_pf_init(void) { return; }
 400 static inline void sctp_v6_pf_exit(void) { return; }
 401 static inline int sctp_v6_protosw_init(void) { return 0; }
 402 static inline void sctp_v6_protosw_exit(void) { return; }
 403 static inline int sctp_v6_add_protocol(void) { return 0; }
 404 static inline void sctp_v6_del_protocol(void) { return; }
 405
 406 #endif /* #if defined(CONFIG_IPV6) */
 407
 408
 409 /* Map an association to an assoc_id. */
 410 static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc)
 411 {
 412         return asoc ? asoc->assoc_id : 0;
 413 }
 414
 415 /* Look up the association by its id.  */
 416 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);
 417
 418 int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp);
 419
 420 /* A macro to walk a list of skbs.  */
 421 #define sctp_skb_for_each(pos, head, tmp) \
 422         skb_queue_walk_safe(head, pos, tmp)
 423
 424 /* A helper to append an entire skb list (list) to another (head). */
 425 static inline void sctp_skb_list_tail(struct sk_buff_head *list,
 426                                       struct sk_buff_head *head)
 427 {
 428         unsigned long flags;
 429
 430         sctp_spin_lock_irqsave(&head->lock, flags);
 431         sctp_spin_lock(&list->lock);
 432
 433         skb_queue_splice_tail_init(list, head);
 434
 435         sctp_spin_unlock(&list->lock);
 436         sctp_spin_unlock_irqrestore(&head->lock, flags);
 437 }
 438
 439 /**
 440  *      sctp_list_dequeue - remove from the head of the queue
 441  *      @list: list to dequeue from
 442  *
 443  *      Remove the head of the list. The head item is
 444  *      returned or %NULL if the list is empty.
 445  */
 446
 447 static inline struct list_head *sctp_list_dequeue(struct list_head *list)
 448 {
 449         struct list_head *result = NULL;
 450
 451         if (list->next != list) {
 452                 result = list->next;
 453                 list->next = result->next;
 454                 list->next->prev = list;
 455                 INIT_LIST_HEAD(result);
 456         }
 457         return result;
 458 }
 459
 460 /* SCTP version of skb_set_owner_r.  We need this one because
 461  * of the way we have to do receive buffer accounting on bundled
 462  * chunks.
 463  */
 464 static inline void sctp_skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
 465 {
 466         struct sctp_ulpevent *event = sctp_skb2event(skb);
 467
 468         skb_orphan(skb);
 469         skb->sk = sk;
 470         skb->destructor = sctp_sock_rfree;
 471         atomic_add(event->rmem_len, &sk->sk_rmem_alloc);
 472         /*
 473          * This mimics the behavior of skb_set_owner_r
 474          */
 475         sk->sk_forward_alloc -= event->rmem_len;
 476 }
 477
 478 /* Tests if the list has one and only one entry. */
 479 static inline int sctp_list_single_entry(struct list_head *head)
 480 {
 481         return (head->next != head) && (head->next == head->prev);
 482 }
 483
 484 /* Generate a random jitter in the range of -50% ~ +50% of input RTO. */
 485 static inline __s32 sctp_jitter(__u32 rto)
 486 {
 487         static __u32 sctp_rand;
 488         __s32 ret;
 489
 490         /* Avoid divide by zero. */
 491         if (!rto)
 492                 rto = 1;
 493
 494         sctp_rand += jiffies;
 495         sctp_rand ^= (sctp_rand << 12);
 496         sctp_rand ^= (sctp_rand >> 20);
 497
 498         /* Choose random number from 0 to rto, then move to -50% ~ +50%
 499          * of rto.
 500          */
 501         ret = sctp_rand % rto - (rto >> 1);
 502         return ret;
 503 }
 504
 505 /* Break down data chunks at this point.  */
 506 static inline int sctp_frag_point(const struct sctp_association *asoc, int pmtu)
 507 {
 508         struct sctp_sock *sp = sctp_sk(asoc->base.sk);
 509         int frag = pmtu;
 510
 511         frag -= sp->pf->af->net_header_len;
 512         frag -= sizeof(struct sctphdr) + sizeof(struct sctp_data_chunk);
 513
 514         if (asoc->user_frag)
 515                 frag = min_t(int, frag, asoc->user_frag);
 516
 517         frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN);
 518
 519         return frag;
 520 }
 521
 522 static inline void sctp_assoc_pending_pmtu(struct sock *sk, struct sctp_association *asoc)
 523 {
 524
 525         sctp_assoc_sync_pmtu(sk, asoc);
 526         asoc->pmtu_pending = 0;
 527 }
 528
 529 /* Walk through a list of TLV parameters.  Don't trust the
 530  * individual parameter lengths and instead depend on
 531  * the chunk length to indicate when to stop.  Make sure
 532  * there is room for a param header too.
 533  */
 534 #define sctp_walk_params(pos, chunk, member)\
 535 _sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length), member)
 536
 537 #define _sctp_walk_params(pos, chunk, end, member)\
 538 for (pos.v = chunk->member;\
 539      pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\
 540      ntohs(pos.p->length) >= sizeof(sctp_paramhdr_t);\
 541      pos.v += WORD_ROUND(ntohs(pos.p->length)))
 542
 543 #define sctp_walk_errors(err, chunk_hdr)\
 544 _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
 545
 546 #define _sctp_walk_errors(err, chunk_hdr, end)\
 547 for (err = (sctp_errhdr_t *)((void *)chunk_hdr + \
 548             sizeof(sctp_chunkhdr_t));\
 549      (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\
 550      ntohs(err->length) >= sizeof(sctp_errhdr_t); \
 551      err = (sctp_errhdr_t *)((void *)err + WORD_ROUND(ntohs(err->length))))
 552
 553 #define sctp_walk_fwdtsn(pos, chunk)\
 554 _sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk))
 555
 556 #define _sctp_walk_fwdtsn(pos, chunk, end)\
 557 for (pos = chunk->subh.fwdtsn_hdr->skip;\
 558      (void *)pos <= (void *)chunk->subh.fwdtsn_hdr->skip + end - sizeof(struct sctp_fwdtsn_skip);\
 559      pos++)
 560
 561 /* Round an int up to the next multiple of 4.  */
 562 #define WORD_ROUND(s) (((s)+3)&~3)
 563
 564 /* Make a new instance of type.  */
 565 #define t_new(type, flags)      (type *)kzalloc(sizeof(type), flags)
 566
 567 /* Compare two timevals.  */
 568 #define tv_lt(s, t) \
 569    (s.tv_sec < t.tv_sec || (s.tv_sec == t.tv_sec && s.tv_usec < t.tv_usec))
 570
 571 /* Add tv1 to tv2. */
 572 #define TIMEVAL_ADD(tv1, tv2) \
 573 ({ \
 574         suseconds_t usecs = (tv2).tv_usec + (tv1).tv_usec; \
 575         time_t secs = (tv2).tv_sec + (tv1).tv_sec; \
 576 \
 577         if (usecs >= 1000000) { \
 578                 usecs -= 1000000; \
 579                 secs++; \
 580         } \
 581         (tv2).tv_sec = secs; \
 582         (tv2).tv_usec = usecs; \
 583 })
 584
 585 /* External references. */
 586
 587 extern struct proto sctp_prot;
 588 extern struct proto sctpv6_prot;
 589 extern struct proc_dir_entry *proc_net_sctp;
 590 void sctp_put_port(struct sock *sk);
 591
 592 extern struct idr sctp_assocs_id;
 593 extern spinlock_t sctp_assocs_id_lock;
 594
 595 /* Static inline functions. */
 596
 597 /* Convert from an IP version number to an Address Family symbol.  */
 598 static inline int ipver2af(__u8 ipver)
 599 {
 600         switch (ipver) {
 601         case 4:
 602                 return  AF_INET;
 603         case 6:
 604                 return AF_INET6;
 605         default:
 606                 return 0;
 607         }
 608 }
 609
 610 /* Convert from an address parameter type to an address family.  */
 611 static inline int param_type2af(__be16 type)
 612 {
 613         switch (type) {
 614         case SCTP_PARAM_IPV4_ADDRESS:
 615                 return  AF_INET;
 616         case SCTP_PARAM_IPV6_ADDRESS:
 617                 return AF_INET6;
 618         default:
 619                 return 0;
 620         }
 621 }
 622
 623 /* Perform some sanity checks. */
 624 static inline int sctp_sanity_check(void)
 625 {
 626         SCTP_ASSERT(sizeof(struct sctp_ulpevent) <=
 627                     sizeof(((struct sk_buff *)0)->cb),
 628                     "SCTP: ulpevent does not fit in skb!\n", return 0);
 629
 630         return 1;
 631 }
 632
 633 /* Warning: The following hash functions assume a power of two 'size'. */
 634 /* This is the hash function for the SCTP port hash table. */
 635 static inline int sctp_phashfn(__u16 lport)
 636 {
 637         return lport & (sctp_port_hashsize - 1);
 638 }
 639
 640 /* This is the hash function for the endpoint hash table. */
 641 static inline int sctp_ep_hashfn(__u16 lport)
 642 {
 643         return lport & (sctp_ep_hashsize - 1);
 644 }
 645
 646 /* This is the hash function for the association hash table. */
 647 static inline int sctp_assoc_hashfn(__u16 lport, __u16 rport)
 648 {
 649         int h = (lport << 16) + rport;
 650         h ^= h>>8;
 651         return h & (sctp_assoc_hashsize - 1);
 652 }
 653
 654 /* This is the hash function for the association hash table.  This is
 655  * not used yet, but could be used as a better hash function when
 656  * we have a vtag.
 657  */
 658 static inline int sctp_vtag_hashfn(__u16 lport, __u16 rport, __u32 vtag)
 659 {
 660         int h = (lport << 16) + rport;
 661         h ^= vtag;
 662         return h & (sctp_assoc_hashsize - 1);
 663 }
 664
 665 #define sctp_for_each_hentry(epb, node, head) \
 666         hlist_for_each_entry(epb, node, head, node)
 667
 668 /* Is a socket of this style? */
 669 #define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
 670 static inline int __sctp_style(const struct sock *sk, sctp_socket_type_t style)
 671 {
 672         return sctp_sk(sk)->type == style;
 673 }
 674
 675 /* Is the association in this state? */
 676 #define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state))
 677 static inline int __sctp_state(const struct sctp_association *asoc,
 678                                sctp_state_t state)
 679 {
 680         return asoc->state == state;
 681 }
 682
 683 /* Is the socket in this state? */
 684 #define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state))
 685 static inline int __sctp_sstate(const struct sock *sk, sctp_sock_state_t state)
 686 {
 687         return sk->sk_state == state;
 688 }
 689
 690 /* Map v4-mapped v6 address back to v4 address */
 691 static inline void sctp_v6_map_v4(union sctp_addr *addr)
 692 {
 693         addr->v4.sin_family = AF_INET;
 694         addr->v4.sin_port = addr->v6.sin6_port;
 695         addr->v4.sin_addr.s_addr = addr->v6.sin6_addr.s6_addr32[3];
 696 }
 697
 698 /* Map v4 address to v4-mapped v6 address */
 699 static inline void sctp_v4_map_v6(union sctp_addr *addr)
 700 {
 701         addr->v6.sin6_family = AF_INET6;
 702         addr->v6.sin6_port = addr->v4.sin_port;
 703         addr->v6.sin6_addr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 704         addr->v6.sin6_addr.s6_addr32[0] = 0;
 705         addr->v6.sin6_addr.s6_addr32[1] = 0;
 706         addr->v6.sin6_addr.s6_addr32[2] = htonl(0x0000ffff);
 707 }
 708
 709 /* The cookie is always 0 since this is how it's used in the
 710  * pmtu code.
 711  */
 712 static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t)
 713 {
 714         if (t->dst && !dst_check(t->dst, 0)) {
 715                 dst_release(t->dst);
 716                 t->dst = NULL;
 717         }
 718
 719         return t->dst;
 720 }
 721
 722 #endif /* __net_sctp_h__ */