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  * Function declarations.
 104  */
 105
 106 /*
 107  * sctp/protocol.c
 108  */
 109 extern int sctp_copy_local_addr_list(struct net *, struct sctp_bind_addr *,
 110                                      sctp_scope_t, gfp_t gfp,
 111                                      int flags);
 112 extern struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
 113 extern int sctp_register_pf(struct sctp_pf *, sa_family_t);
 114 extern void sctp_addr_wq_mgmt(struct net *, struct sctp_sockaddr_entry *, int);
 115
 116 /*
 117  * sctp/socket.c
 118  */
 119 int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb);
 120 int sctp_inet_listen(struct socket *sock, int backlog);
 121 void sctp_write_space(struct sock *sk);
 122 void sctp_data_ready(struct sock *sk, int len);
 123 unsigned int sctp_poll(struct file *file, struct socket *sock,
 124                 poll_table *wait);
 125 void sctp_sock_rfree(struct sk_buff *skb);
 126 void sctp_copy_sock(struct sock *newsk, struct sock *sk,
 127                     struct sctp_association *asoc);
 128 extern struct percpu_counter sctp_sockets_allocated;
 129 extern int sctp_asconf_mgmt(struct sctp_sock *, struct sctp_sockaddr_entry *);
 130
 131 /*
 132  * sctp/primitive.c
 133  */
 134 int sctp_primitive_ASSOCIATE(struct net *, struct sctp_association *, void *arg);
 135 int sctp_primitive_SHUTDOWN(struct net *, struct sctp_association *, void *arg);
 136 int sctp_primitive_ABORT(struct net *, struct sctp_association *, void *arg);
 137 int sctp_primitive_SEND(struct net *, struct sctp_association *, void *arg);
 138 int sctp_primitive_REQUESTHEARTBEAT(struct net *, struct sctp_association *, void *arg);
 139 int sctp_primitive_ASCONF(struct net *, struct sctp_association *, void *arg);
 140
 141 /*
 142  * sctp/input.c
 143  */
 144 int sctp_rcv(struct sk_buff *skb);
 145 void sctp_v4_err(struct sk_buff *skb, u32 info);
 146 void sctp_hash_established(struct sctp_association *);
 147 void sctp_unhash_established(struct sctp_association *);
 148 void sctp_hash_endpoint(struct sctp_endpoint *);
 149 void sctp_unhash_endpoint(struct sctp_endpoint *);
 150 struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *,
 151                              struct sctphdr *, struct sctp_association **,
 152                              struct sctp_transport **);
 153 void sctp_err_finish(struct sock *, struct sctp_association *);
 154 void sctp_icmp_frag_needed(struct sock *, struct sctp_association *,
 155                            struct sctp_transport *t, __u32 pmtu);
 156 void sctp_icmp_redirect(struct sock *, struct sctp_transport *,
 157                         struct sk_buff *);
 158 void sctp_icmp_proto_unreachable(struct sock *sk,
 159                                  struct sctp_association *asoc,
 160                                  struct sctp_transport *t);
 161 void sctp_backlog_migrate(struct sctp_association *assoc,
 162                           struct sock *oldsk, struct sock *newsk);
 163
 164 /*
 165  * sctp/proc.c
 166  */
 167 int sctp_snmp_proc_init(struct net *net);
 168 void sctp_snmp_proc_exit(struct net *net);
 169 int sctp_eps_proc_init(struct net *net);
 170 void sctp_eps_proc_exit(struct net *net);
 171 int sctp_assocs_proc_init(struct net *net);
 172 void sctp_assocs_proc_exit(struct net *net);
 173 int sctp_remaddr_proc_init(struct net *net);
 174 void sctp_remaddr_proc_exit(struct net *net);
 175
 176
 177 /*
 178  * Module global variables
 179  */
 180
 181  /*
 182   * sctp/protocol.c
 183   */
 184 extern struct kmem_cache *sctp_chunk_cachep __read_mostly;
 185 extern struct kmem_cache *sctp_bucket_cachep __read_mostly;
 186
 187 /*
 188  *  Section:  Macros, externs, and inlines
 189  */
 190
 191 /* spin lock wrappers. */
 192 #define sctp_spin_lock_irqsave(lock, flags) spin_lock_irqsave(lock, flags)
 193 #define sctp_spin_unlock_irqrestore(lock, flags)  \
 194        spin_unlock_irqrestore(lock, flags)
 195 #define sctp_local_bh_disable() local_bh_disable()
 196 #define sctp_local_bh_enable()  local_bh_enable()
 197 #define sctp_spin_lock(lock)    spin_lock(lock)
 198 #define sctp_spin_unlock(lock)  spin_unlock(lock)
 199 #define sctp_write_lock(lock)   write_lock(lock)
 200 #define sctp_write_unlock(lock) write_unlock(lock)
 201 #define sctp_read_lock(lock)    read_lock(lock)
 202 #define sctp_read_unlock(lock)  read_unlock(lock)
 203
 204 /* sock lock wrappers. */
 205 #define sctp_lock_sock(sk)       lock_sock(sk)
 206 #define sctp_release_sock(sk)    release_sock(sk)
 207 #define sctp_bh_lock_sock(sk)    bh_lock_sock(sk)
 208 #define sctp_bh_unlock_sock(sk)  bh_unlock_sock(sk)
 209
 210 /* SCTP SNMP MIB stats handlers */
 211 #define SCTP_INC_STATS(net, field)      SNMP_INC_STATS((net)->sctp.sctp_statistics, field)
 212 #define SCTP_INC_STATS_BH(net, field)   SNMP_INC_STATS_BH((net)->sctp.sctp_statistics, field)
 213 #define SCTP_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)->sctp.sctp_statistics, field)
 214 #define SCTP_DEC_STATS(net, field)      SNMP_DEC_STATS((net)->sctp.sctp_statistics, field)
 215
 216 /* sctp mib definitions */
 217 enum {
 218         SCTP_MIB_NUM = 0,
 219         SCTP_MIB_CURRESTAB,                     /* CurrEstab */
 220         SCTP_MIB_ACTIVEESTABS,                  /* ActiveEstabs */
 221         SCTP_MIB_PASSIVEESTABS,                 /* PassiveEstabs */
 222         SCTP_MIB_ABORTEDS,                      /* Aborteds */
 223         SCTP_MIB_SHUTDOWNS,                     /* Shutdowns */
 224         SCTP_MIB_OUTOFBLUES,                    /* OutOfBlues */
 225         SCTP_MIB_CHECKSUMERRORS,                /* ChecksumErrors */
 226         SCTP_MIB_OUTCTRLCHUNKS,                 /* OutCtrlChunks */
 227         SCTP_MIB_OUTORDERCHUNKS,                /* OutOrderChunks */
 228         SCTP_MIB_OUTUNORDERCHUNKS,              /* OutUnorderChunks */
 229         SCTP_MIB_INCTRLCHUNKS,                  /* InCtrlChunks */
 230         SCTP_MIB_INORDERCHUNKS,                 /* InOrderChunks */
 231         SCTP_MIB_INUNORDERCHUNKS,               /* InUnorderChunks */
 232         SCTP_MIB_FRAGUSRMSGS,                   /* FragUsrMsgs */
 233         SCTP_MIB_REASMUSRMSGS,                  /* ReasmUsrMsgs */
 234         SCTP_MIB_OUTSCTPPACKS,                  /* OutSCTPPacks */
 235         SCTP_MIB_INSCTPPACKS,                   /* InSCTPPacks */
 236         SCTP_MIB_T1_INIT_EXPIREDS,
 237         SCTP_MIB_T1_COOKIE_EXPIREDS,
 238         SCTP_MIB_T2_SHUTDOWN_EXPIREDS,
 239         SCTP_MIB_T3_RTX_EXPIREDS,
 240         SCTP_MIB_T4_RTO_EXPIREDS,
 241         SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS,
 242         SCTP_MIB_DELAY_SACK_EXPIREDS,
 243         SCTP_MIB_AUTOCLOSE_EXPIREDS,
 244         SCTP_MIB_T1_RETRANSMITS,
 245         SCTP_MIB_T3_RETRANSMITS,
 246         SCTP_MIB_PMTUD_RETRANSMITS,
 247         SCTP_MIB_FAST_RETRANSMITS,
 248         SCTP_MIB_IN_PKT_SOFTIRQ,
 249         SCTP_MIB_IN_PKT_BACKLOG,
 250         SCTP_MIB_IN_PKT_DISCARDS,
 251         SCTP_MIB_IN_DATA_CHUNK_DISCARDS,
 252         __SCTP_MIB_MAX
 253 };
 254
 255 #define SCTP_MIB_MAX    __SCTP_MIB_MAX
 256 struct sctp_mib {
 257         unsigned long   mibs[SCTP_MIB_MAX];
 258 };
 259
 260 /* helper function to track stats about max rto and related transport */
 261 static inline void sctp_max_rto(struct sctp_association *asoc,
 262                                 struct sctp_transport *trans)
 263 {
 264         if (asoc->stats.max_obs_rto < (__u64)trans->rto) {
 265                 asoc->stats.max_obs_rto = trans->rto;
 266                 memset(&asoc->stats.obs_rto_ipaddr, 0,
 267                         sizeof(struct sockaddr_storage));
 268                 memcpy(&asoc->stats.obs_rto_ipaddr, &trans->ipaddr,
 269                         trans->af_specific->sockaddr_len);
 270         }
 271 }
 272
 273 /* Print debugging messages.  */
 274 #if SCTP_DEBUG
 275 extern int sctp_debug_flag;
 276 #define SCTP_DEBUG_PRINTK(fmt, args...)                 \
 277 do {                                                    \
 278         if (sctp_debug_flag)                            \
 279                 printk(KERN_DEBUG pr_fmt(fmt), ##args); \
 280 } while (0)
 281 #define SCTP_DEBUG_PRINTK_CONT(fmt, args...)            \
 282 do {                                                    \
 283         if (sctp_debug_flag)                            \
 284                 pr_cont(fmt, ##args);                   \
 285 } while (0)
 286 #define SCTP_DEBUG_PRINTK_IPADDR(fmt_lead, fmt_trail,                   \
 287                                  args_lead, addr, args_trail...)        \
 288 do {                                                                    \
 289         const union sctp_addr *_addr = (addr);                          \
 290         if (sctp_debug_flag) {                                          \
 291                 if (_addr->sa.sa_family == AF_INET6) {                  \
 292                         printk(KERN_DEBUG                               \
 293                                pr_fmt(fmt_lead "%pI6" fmt_trail),       \
 294                                args_lead,                               \
 295                                &_addr->v6.sin6_addr,                    \
 296                                args_trail);                             \
 297                 } else {                                                \
 298                         printk(KERN_DEBUG                               \
 299                                pr_fmt(fmt_lead "%pI4" fmt_trail),       \
 300                                args_lead,                               \
 301                                &_addr->v4.sin_addr.s_addr,              \
 302                                args_trail);                             \
 303                 }                                                       \
 304         }                                                               \
 305 } while (0)
 306 #define SCTP_ENABLE_DEBUG { sctp_debug_flag = 1; }
 307 #define SCTP_DISABLE_DEBUG { sctp_debug_flag = 0; }
 308
 309 #define SCTP_ASSERT(expr, str, func) \
 310         if (!(expr)) { \
 311                 SCTP_DEBUG_PRINTK("Assertion Failed: %s(%s) at %s:%s:%d\n", \
 312                         str, (#expr), __FILE__, __func__, __LINE__); \
 313                 func; \
 314         }
 315
 316 #else   /* SCTP_DEBUG */
 317
 318 #define SCTP_DEBUG_PRINTK(whatever...)
 319 #define SCTP_DEBUG_PRINTK_CONT(fmt, args...)
 320 #define SCTP_DEBUG_PRINTK_IPADDR(whatever...)
 321 #define SCTP_ENABLE_DEBUG
 322 #define SCTP_DISABLE_DEBUG
 323 #define SCTP_ASSERT(expr, str, func)
 324
 325 #endif /* SCTP_DEBUG */
 326
 327
 328 /*
 329  * Macros for keeping a global reference of object allocations.
 330  */
 331 #ifdef CONFIG_SCTP_DBG_OBJCNT
 332
 333 extern atomic_t sctp_dbg_objcnt_sock;
 334 extern atomic_t sctp_dbg_objcnt_ep;
 335 extern atomic_t sctp_dbg_objcnt_assoc;
 336 extern atomic_t sctp_dbg_objcnt_transport;
 337 extern atomic_t sctp_dbg_objcnt_chunk;
 338 extern atomic_t sctp_dbg_objcnt_bind_addr;
 339 extern atomic_t sctp_dbg_objcnt_bind_bucket;
 340 extern atomic_t sctp_dbg_objcnt_addr;
 341 extern atomic_t sctp_dbg_objcnt_ssnmap;
 342 extern atomic_t sctp_dbg_objcnt_datamsg;
 343 extern atomic_t sctp_dbg_objcnt_keys;
 344
 345 /* Macros to atomically increment/decrement objcnt counters.  */
 346 #define SCTP_DBG_OBJCNT_INC(name) \
 347 atomic_inc(&sctp_dbg_objcnt_## name)
 348 #define SCTP_DBG_OBJCNT_DEC(name) \
 349 atomic_dec(&sctp_dbg_objcnt_## name)
 350 #define SCTP_DBG_OBJCNT(name) \
 351 atomic_t sctp_dbg_objcnt_## name = ATOMIC_INIT(0)
 352
 353 /* Macro to help create new entries in in the global array of
 354  * objcnt counters.
 355  */
 356 #define SCTP_DBG_OBJCNT_ENTRY(name) \
 357 {.label= #name, .counter= &sctp_dbg_objcnt_## name}
 358
 359 void sctp_dbg_objcnt_init(struct net *);
 360 void sctp_dbg_objcnt_exit(struct net *);
 361
 362 #else
 363
 364 #define SCTP_DBG_OBJCNT_INC(name)
 365 #define SCTP_DBG_OBJCNT_DEC(name)
 366
 367 static inline void sctp_dbg_objcnt_init(struct net *net) { return; }
 368 static inline void sctp_dbg_objcnt_exit(struct net *net) { return; }
 369
 370 #endif /* CONFIG_SCTP_DBG_OBJCOUNT */
 371
 372 #if defined CONFIG_SYSCTL
 373 void sctp_sysctl_register(void);
 374 void sctp_sysctl_unregister(void);
 375 int sctp_sysctl_net_register(struct net *net);
 376 void sctp_sysctl_net_unregister(struct net *net);
 377 #else
 378 static inline void sctp_sysctl_register(void) { return; }
 379 static inline void sctp_sysctl_unregister(void) { return; }
 380 static inline int sctp_sysctl_net_register(struct net *net) { return 0; }
 381 static inline void sctp_sysctl_net_unregister(struct net *net) { return; }
 382 #endif
 383
 384 /* Size of Supported Address Parameter for 'x' address types. */
 385 #define SCTP_SAT_LEN(x) (sizeof(struct sctp_paramhdr) + (x) * sizeof(__u16))
 386
 387 #if IS_ENABLED(CONFIG_IPV6)
 388
 389 void sctp_v6_pf_init(void);
 390 void sctp_v6_pf_exit(void);
 391 int sctp_v6_protosw_init(void);
 392 void sctp_v6_protosw_exit(void);
 393 int sctp_v6_add_protocol(void);
 394 void sctp_v6_del_protocol(void);
 395
 396 #else /* #ifdef defined(CONFIG_IPV6) */
 397
 398 static inline void sctp_v6_pf_init(void) { return; }
 399 static inline void sctp_v6_pf_exit(void) { return; }
 400 static inline int sctp_v6_protosw_init(void) { return 0; }
 401 static inline void sctp_v6_protosw_exit(void) { return; }
 402 static inline int sctp_v6_add_protocol(void) { return 0; }
 403 static inline void sctp_v6_del_protocol(void) { return; }
 404
 405 #endif /* #if defined(CONFIG_IPV6) */
 406
 407
 408 /* Map an association to an assoc_id. */
 409 static inline sctp_assoc_t sctp_assoc2id(const struct sctp_association *asoc)
 410 {
 411         return asoc ? asoc->assoc_id : 0;
 412 }
 413
 414 /* Look up the association by its id.  */
 415 struct sctp_association *sctp_id2assoc(struct sock *sk, sctp_assoc_t id);
 416
 417 int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp);
 418
 419 /* A macro to walk a list of skbs.  */
 420 #define sctp_skb_for_each(pos, head, tmp) \
 421         skb_queue_walk_safe(head, pos, tmp)
 422
 423 /* A helper to append an entire skb list (list) to another (head). */
 424 static inline void sctp_skb_list_tail(struct sk_buff_head *list,
 425                                       struct sk_buff_head *head)
 426 {
 427         unsigned long flags;
 428
 429         sctp_spin_lock_irqsave(&head->lock, flags);
 430         sctp_spin_lock(&list->lock);
 431
 432         skb_queue_splice_tail_init(list, head);
 433
 434         sctp_spin_unlock(&list->lock);
 435         sctp_spin_unlock_irqrestore(&head->lock, flags);
 436 }
 437
 438 /**
 439  *      sctp_list_dequeue - remove from the head of the queue
 440  *      @list: list to dequeue from
 441  *
 442  *      Remove the head of the list. The head item is
 443  *      returned or %NULL if the list is empty.
 444  */
 445
 446 static inline struct list_head *sctp_list_dequeue(struct list_head *list)
 447 {
 448         struct list_head *result = NULL;
 449
 450         if (list->next != list) {
 451                 result = list->next;
 452                 list->next = result->next;
 453                 list->next->prev = list;
 454                 INIT_LIST_HEAD(result);
 455         }
 456         return result;
 457 }
 458
 459 /* SCTP version of skb_set_owner_r.  We need this one because
 460  * of the way we have to do receive buffer accounting on bundled
 461  * chunks.
 462  */
 463 static inline void sctp_skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
 464 {
 465         struct sctp_ulpevent *event = sctp_skb2event(skb);
 466
 467         skb_orphan(skb);
 468         skb->sk = sk;
 469         skb->destructor = sctp_sock_rfree;
 470         atomic_add(event->rmem_len, &sk->sk_rmem_alloc);
 471         /*
 472          * This mimics the behavior of skb_set_owner_r
 473          */
 474         sk->sk_forward_alloc -= event->rmem_len;
 475 }
 476
 477 /* Tests if the list has one and only one entry. */
 478 static inline int sctp_list_single_entry(struct list_head *head)
 479 {
 480         return (head->next != head) && (head->next == head->prev);
 481 }
 482
 483 /* Generate a random jitter in the range of -50% ~ +50% of input RTO. */
 484 static inline __s32 sctp_jitter(__u32 rto)
 485 {
 486         static __u32 sctp_rand;
 487         __s32 ret;
 488
 489         /* Avoid divide by zero. */
 490         if (!rto)
 491                 rto = 1;
 492
 493         sctp_rand += jiffies;
 494         sctp_rand ^= (sctp_rand << 12);
 495         sctp_rand ^= (sctp_rand >> 20);
 496
 497         /* Choose random number from 0 to rto, then move to -50% ~ +50%
 498          * of rto.
 499          */
 500         ret = sctp_rand % rto - (rto >> 1);
 501         return ret;
 502 }
 503
 504 /* Break down data chunks at this point.  */
 505 static inline int sctp_frag_point(const struct sctp_association *asoc, int pmtu)
 506 {
 507         struct sctp_sock *sp = sctp_sk(asoc->base.sk);
 508         int frag = pmtu;
 509
 510         frag -= sp->pf->af->net_header_len;
 511         frag -= sizeof(struct sctphdr) + sizeof(struct sctp_data_chunk);
 512
 513         if (asoc->user_frag)
 514                 frag = min_t(int, frag, asoc->user_frag);
 515
 516         frag = min_t(int, frag, SCTP_MAX_CHUNK_LEN);
 517
 518         return frag;
 519 }
 520
 521 static inline void sctp_assoc_pending_pmtu(struct sock *sk, struct sctp_association *asoc)
 522 {
 523
 524         sctp_assoc_sync_pmtu(sk, asoc);
 525         asoc->pmtu_pending = 0;
 526 }
 527
 528 /* Walk through a list of TLV parameters.  Don't trust the
 529  * individual parameter lengths and instead depend on
 530  * the chunk length to indicate when to stop.  Make sure
 531  * there is room for a param header too.
 532  */
 533 #define sctp_walk_params(pos, chunk, member)\
 534 _sctp_walk_params((pos), (chunk), ntohs((chunk)->chunk_hdr.length), member)
 535
 536 #define _sctp_walk_params(pos, chunk, end, member)\
 537 for (pos.v = chunk->member;\
 538      pos.v <= (void *)chunk + end - ntohs(pos.p->length) &&\
 539      ntohs(pos.p->length) >= sizeof(sctp_paramhdr_t);\
 540      pos.v += WORD_ROUND(ntohs(pos.p->length)))
 541
 542 #define sctp_walk_errors(err, chunk_hdr)\
 543 _sctp_walk_errors((err), (chunk_hdr), ntohs((chunk_hdr)->length))
 544
 545 #define _sctp_walk_errors(err, chunk_hdr, end)\
 546 for (err = (sctp_errhdr_t *)((void *)chunk_hdr + \
 547             sizeof(sctp_chunkhdr_t));\
 548      (void *)err <= (void *)chunk_hdr + end - ntohs(err->length) &&\
 549      ntohs(err->length) >= sizeof(sctp_errhdr_t); \
 550      err = (sctp_errhdr_t *)((void *)err + WORD_ROUND(ntohs(err->length))))
 551
 552 #define sctp_walk_fwdtsn(pos, chunk)\
 553 _sctp_walk_fwdtsn((pos), (chunk), ntohs((chunk)->chunk_hdr->length) - sizeof(struct sctp_fwdtsn_chunk))
 554
 555 #define _sctp_walk_fwdtsn(pos, chunk, end)\
 556 for (pos = chunk->subh.fwdtsn_hdr->skip;\
 557      (void *)pos <= (void *)chunk->subh.fwdtsn_hdr->skip + end - sizeof(struct sctp_fwdtsn_skip);\
 558      pos++)
 559
 560 /* Round an int up to the next multiple of 4.  */
 561 #define WORD_ROUND(s) (((s)+3)&~3)
 562
 563 /* External references. */
 564
 565 extern struct proto sctp_prot;
 566 extern struct proto sctpv6_prot;
 567 void sctp_put_port(struct sock *sk);
 568
 569 extern struct idr sctp_assocs_id;
 570 extern spinlock_t sctp_assocs_id_lock;
 571
 572 /* Static inline functions. */
 573
 574 /* Convert from an IP version number to an Address Family symbol.  */
 575 static inline int ipver2af(__u8 ipver)
 576 {
 577         switch (ipver) {
 578         case 4:
 579                 return  AF_INET;
 580         case 6:
 581                 return AF_INET6;
 582         default:
 583                 return 0;
 584         }
 585 }
 586
 587 /* Convert from an address parameter type to an address family.  */
 588 static inline int param_type2af(__be16 type)
 589 {
 590         switch (type) {
 591         case SCTP_PARAM_IPV4_ADDRESS:
 592                 return  AF_INET;
 593         case SCTP_PARAM_IPV6_ADDRESS:
 594                 return AF_INET6;
 595         default:
 596                 return 0;
 597         }
 598 }
 599
 600 /* Perform some sanity checks. */
 601 static inline int sctp_sanity_check(void)
 602 {
 603         SCTP_ASSERT(sizeof(struct sctp_ulpevent) <=
 604                     sizeof(((struct sk_buff *)0)->cb),
 605                     "SCTP: ulpevent does not fit in skb!\n", return 0);
 606
 607         return 1;
 608 }
 609
 610 /* Warning: The following hash functions assume a power of two 'size'. */
 611 /* This is the hash function for the SCTP port hash table. */
 612 static inline int sctp_phashfn(struct net *net, __u16 lport)
 613 {
 614         return (net_hash_mix(net) + lport) & (sctp_port_hashsize - 1);
 615 }
 616
 617 /* This is the hash function for the endpoint hash table. */
 618 static inline int sctp_ep_hashfn(struct net *net, __u16 lport)
 619 {
 620         return (net_hash_mix(net) + lport) & (sctp_ep_hashsize - 1);
 621 }
 622
 623 /* This is the hash function for the association hash table. */
 624 static inline int sctp_assoc_hashfn(struct net *net, __u16 lport, __u16 rport)
 625 {
 626         int h = (lport << 16) + rport + net_hash_mix(net);
 627         h ^= h>>8;
 628         return h & (sctp_assoc_hashsize - 1);
 629 }
 630
 631 /* This is the hash function for the association hash table.  This is
 632  * not used yet, but could be used as a better hash function when
 633  * we have a vtag.
 634  */
 635 static inline int sctp_vtag_hashfn(__u16 lport, __u16 rport, __u32 vtag)
 636 {
 637         int h = (lport << 16) + rport;
 638         h ^= vtag;
 639         return h & (sctp_assoc_hashsize - 1);
 640 }
 641
 642 #define sctp_for_each_hentry(epb, head) \
 643         hlist_for_each_entry(epb, head, node)
 644
 645 /* Is a socket of this style? */
 646 #define sctp_style(sk, style) __sctp_style((sk), (SCTP_SOCKET_##style))
 647 static inline int __sctp_style(const struct sock *sk, sctp_socket_type_t style)
 648 {
 649         return sctp_sk(sk)->type == style;
 650 }
 651
 652 /* Is the association in this state? */
 653 #define sctp_state(asoc, state) __sctp_state((asoc), (SCTP_STATE_##state))
 654 static inline int __sctp_state(const struct sctp_association *asoc,
 655                                sctp_state_t state)
 656 {
 657         return asoc->state == state;
 658 }
 659
 660 /* Is the socket in this state? */
 661 #define sctp_sstate(sk, state) __sctp_sstate((sk), (SCTP_SS_##state))
 662 static inline int __sctp_sstate(const struct sock *sk, sctp_sock_state_t state)
 663 {
 664         return sk->sk_state == state;
 665 }
 666
 667 /* Map v4-mapped v6 address back to v4 address */
 668 static inline void sctp_v6_map_v4(union sctp_addr *addr)
 669 {
 670         addr->v4.sin_family = AF_INET;
 671         addr->v4.sin_port = addr->v6.sin6_port;
 672         addr->v4.sin_addr.s_addr = addr->v6.sin6_addr.s6_addr32[3];
 673 }
 674
 675 /* Map v4 address to v4-mapped v6 address */
 676 static inline void sctp_v4_map_v6(union sctp_addr *addr)
 677 {
 678         addr->v6.sin6_family = AF_INET6;
 679         addr->v6.sin6_port = addr->v4.sin_port;
 680         addr->v6.sin6_addr.s6_addr32[3] = addr->v4.sin_addr.s_addr;
 681         addr->v6.sin6_addr.s6_addr32[0] = 0;
 682         addr->v6.sin6_addr.s6_addr32[1] = 0;
 683         addr->v6.sin6_addr.s6_addr32[2] = htonl(0x0000ffff);
 684 }
 685
 686 /* The cookie is always 0 since this is how it's used in the
 687  * pmtu code.
 688  */
 689 static inline struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t)
 690 {
 691         if (t->dst && !dst_check(t->dst, 0)) {
 692                 dst_release(t->dst);
 693                 t->dst = NULL;
 694         }
 695
 696         return t->dst;
 697 }
 698
 699 #endif /* __net_sctp_h__ */