sys/netinet/sctp_os_bsd.h

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 2006-2007, by Cisco Systems, Inc. All rights reserved.
   5  * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
   6  * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are met:
  10  *
  11  * a) Redistributions of source code must retain the above copyright notice,
  12  *   this list of conditions and the following disclaimer.
  13  *
  14  * b) Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in
  16  *   the documentation and/or other materials provided with the distribution.
  17  *
  18  * c) Neither the name of Cisco Systems, Inc. nor the names of its
  19  *    contributors may be used to endorse or promote products derived
  20  *    from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  23  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  24  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  26  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  32  * THE POSSIBILITY OF SUCH DAMAGE.
  33  */
  34
  35 #ifndef _NETINET_SCTP_OS_BSD_H_
  36 #define _NETINET_SCTP_OS_BSD_H_
  37
  38 #include <sys/cdefs.h>
  39 #include "opt_inet6.h"
  40 #include "opt_inet.h"
  41 #include "opt_sctp.h"
  42
  43 #include <sys/param.h>
  44 #include <sys/domain.h>
  45 #include <sys/eventhandler.h>
  46 #include <sys/ktr.h>
  47 #include <sys/systm.h>
  48 #include <sys/malloc.h>
  49 #include <sys/module.h>
  50 #include <sys/kernel.h>
  51 #include <sys/sysctl.h>
  52 #include <sys/mbuf.h>
  53 #include <sys/protosw.h>
  54 #include <sys/socket.h>
  55 #include <sys/socketvar.h>
  56 #include <sys/jail.h>
  57 #include <sys/sysctl.h>
  58 #include <sys/resourcevar.h>
  59 #include <sys/uio.h>
  60 #include <sys/lock.h>
  61 #include <sys/rwlock.h>
  62 #include <sys/kthread.h>
  63 #include <sys/priv.h>
  64 #include <sys/random.h>
  65 #include <sys/limits.h>
  66 #include <sys/queue.h>
  67 #include <machine/cpu.h>
  68
  69 #include <net/if.h>
  70 #include <net/if_types.h>
  71 #include <net/if_var.h>
  72 #include <net/if_private.h>
  73 #include <net/route.h>
  74 #include <net/route/nhop.h>
  75 #include <net/vnet.h>
  76
  77 #include <netinet/in.h>
  78 #include <netinet/in_systm.h>
  79 #include <netinet/ip.h>
  80 #include <netinet/in_fib.h>
  81 #include <netinet/in_pcb.h>
  82 #include <netinet/in_var.h>
  83 #include <netinet/ip_var.h>
  84 #include <netinet/ip_icmp.h>
  85 #include <netinet/icmp_var.h>
  86
  87 #ifdef INET6
  88 #include <netinet/ip6.h>
  89 #include <netinet6/in6_fib.h>
  90 #include <netinet6/ip6_var.h>
  91 #include <netinet6/in6_pcb.h>
  92 #include <netinet6/nd6.h>
  93 #include <netinet6/scope6_var.h>
  94 #endif                          /* INET6 */
  95
  96 #include <netinet/ip_options.h>
  97
  98 #include <crypto/sha1.h>
  99 #include <crypto/sha2/sha256.h>
 100
 101 /* Declare all the malloc names for all the various mallocs */
 102 MALLOC_DECLARE(SCTP_M_MAP);
 103 MALLOC_DECLARE(SCTP_M_STRMI);
 104 MALLOC_DECLARE(SCTP_M_STRMO);
 105 MALLOC_DECLARE(SCTP_M_ASC_ADDR);
 106 MALLOC_DECLARE(SCTP_M_ASC_IT);
 107 MALLOC_DECLARE(SCTP_M_AUTH_CL);
 108 MALLOC_DECLARE(SCTP_M_AUTH_KY);
 109 MALLOC_DECLARE(SCTP_M_AUTH_HL);
 110 MALLOC_DECLARE(SCTP_M_AUTH_IF);
 111 MALLOC_DECLARE(SCTP_M_STRESET);
 112 MALLOC_DECLARE(SCTP_M_CMSG);
 113 MALLOC_DECLARE(SCTP_M_COPYAL);
 114 MALLOC_DECLARE(SCTP_M_VRF);
 115 MALLOC_DECLARE(SCTP_M_IFA);
 116 MALLOC_DECLARE(SCTP_M_IFN);
 117 MALLOC_DECLARE(SCTP_M_TIMW);
 118 MALLOC_DECLARE(SCTP_M_MVRF);
 119 MALLOC_DECLARE(SCTP_M_ITER);
 120 MALLOC_DECLARE(SCTP_M_SOCKOPT);
 121 MALLOC_DECLARE(SCTP_M_MCORE);
 122
 123 #if defined(SCTP_LOCAL_TRACE_BUF)
 124
 125 #define SCTP_GET_CYCLECOUNT get_cyclecount()
 126 #define SCTP_CTR6 sctp_log_trace
 127
 128 #else
 129 #define SCTP_CTR6 CTR6
 130 #endif
 131
 132 /*
 133  * Macros to expand out globals defined by various modules
 134  * to either a real global or a virtualized instance of one,
 135  * depending on whether VIMAGE is defined.
 136  */
 137 /* then define the macro(s) that hook into the vimage macros */
 138 #define MODULE_GLOBAL(__SYMBOL) V_##__SYMBOL
 139
 140 #define V_system_base_info VNET(system_base_info)
 141 #define SCTP_BASE_INFO(__m) V_system_base_info.sctppcbinfo.__m
 142 #define SCTP_BASE_STATS V_system_base_info.sctpstat
 143 #define SCTP_BASE_STAT(__m) V_system_base_info.sctpstat.__m
 144 #define SCTP_BASE_SYSCTL(__m) V_system_base_info.sctpsysctl.__m
 145 #define SCTP_BASE_VAR(__m) V_system_base_info.__m
 146
 147 #define SCTP_PRINTF(params...)  printf(params)
 148 #if defined(SCTP_DEBUG)
 149 #define SCTPDBG(level, params...)                                       \
 150 {                                                                       \
 151         do {                                                            \
 152                 if (SCTP_BASE_SYSCTL(sctp_debug_on) & level ) {         \
 153                         SCTP_PRINTF(params);                            \
 154                 }                                                       \
 155         } while (0);                                                    \
 156 }
 157 #define SCTPDBG_ADDR(level, addr)                                       \
 158 {                                                                       \
 159         do {                                                            \
 160                 if (SCTP_BASE_SYSCTL(sctp_debug_on) & level ) {         \
 161                         sctp_print_address(addr);                       \
 162                 }                                                       \
 163         } while (0);                                                    \
 164 }
 165 #else
 166 #define SCTPDBG(level, params...)
 167 #define SCTPDBG_ADDR(level, addr)
 168 #endif
 169
 170 #ifdef SCTP_LTRACE_CHUNKS
 171 #define SCTP_LTRACE_CHK(a, b, c, d) if(SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LTRACE_CHUNK_ENABLE) SCTP_CTR6(KTR_SUBSYS, "SCTP:%d[%d]:%x-%x-%x-%x", SCTP_LOG_CHUNK_PROC, 0, a, b, c, d)
 172 #else
 173 #define SCTP_LTRACE_CHK(a, b, c, d)
 174 #endif
 175
 176 #ifdef SCTP_LTRACE_ERRORS
 177 #define SCTP_LTRACE_ERR_RET_PKT(m, inp, stcb, net, file, err) \
 178         if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LTRACE_ERROR_ENABLE) \
 179                 SCTP_PRINTF("mbuf:%p inp:%p stcb:%p net:%p file:%x line:%d error:%d\n", \
 180                             m, inp, stcb, net, file, __LINE__, err);
 181 #define SCTP_LTRACE_ERR_RET(inp, stcb, net, file, err) \
 182         if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LTRACE_ERROR_ENABLE) \
 183                 SCTP_PRINTF("inp:%p stcb:%p net:%p file:%x line:%d error:%d\n", \
 184                             inp, stcb, net, file, __LINE__, err);
 185 #else
 186 #define SCTP_LTRACE_ERR_RET_PKT(m, inp, stcb, net, file, err)
 187 #define SCTP_LTRACE_ERR_RET(inp, stcb, net, file, err)
 188 #endif
 189
 190 /*
 191  * Local address and interface list handling
 192  */
 193 #define SCTP_MAX_VRF_ID         0
 194 #define SCTP_SIZE_OF_VRF_HASH   3
 195 #define SCTP_IFNAMSIZ           IFNAMSIZ
 196 #define SCTP_DEFAULT_VRFID      0
 197 #define SCTP_VRF_ADDR_HASH_SIZE 16
 198 #define SCTP_VRF_IFN_HASH_SIZE  3
 199 #define SCTP_INIT_VRF_TABLEID(vrf)
 200
 201 #define SCTP_IFN_IS_IFT_LOOP(ifn) ((ifn)->ifn_type == IFT_LOOP)
 202 #define SCTP_ROUTE_IS_REAL_LOOP(ro) ((ro)->ro_nh && (ro)->ro_nh->nh_ifa && (ro)->ro_nh->nh_ifa->ifa_ifp && (ro)->ro_nh->nh_ifa->ifa_ifp->if_type == IFT_LOOP)
 203
 204 /*
 205  * Access to IFN's to help with src-addr-selection
 206  */
 207 /* This could return VOID if the index works but for BSD we provide both. */
 208 #define SCTP_GET_IFN_VOID_FROM_ROUTE(ro) (void *)ro->ro_nh->nh_ifp
 209 #define SCTP_GET_IF_INDEX_FROM_ROUTE(ro) (ro)->ro_nh->nh_ifp->if_index
 210 #define SCTP_ROUTE_HAS_VALID_IFN(ro) ((ro)->ro_nh && (ro)->ro_nh->nh_ifp)
 211
 212 /*
 213  * general memory allocation
 214  */
 215 #define SCTP_MALLOC(var, type, size, name) \
 216         do { \
 217                 var = (type)malloc(size, name, M_NOWAIT); \
 218         } while (0)
 219
 220 #define SCTP_FREE(var, type)    free(var, type)
 221
 222 #define SCTP_PROCESS_STRUCT struct proc *
 223
 224 /*
 225  * zone allocation functions
 226  */
 227 #include <vm/uma.h>
 228
 229 /* SCTP_ZONE_INIT: initialize the zone */
 230 typedef struct uma_zone *sctp_zone_t;
 231 #define SCTP_ZONE_INIT(zone, name, size, number) { \
 232         zone = uma_zcreate(name, size, NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,\
 233                 0); \
 234         uma_zone_set_max(zone, number); \
 235 }
 236
 237 #define SCTP_ZONE_DESTROY(zone) uma_zdestroy(zone)
 238
 239 /* SCTP_ZONE_GET: allocate element from the zone */
 240 #define SCTP_ZONE_GET(zone, type) \
 241         (type *)uma_zalloc(zone, M_NOWAIT);
 242
 243 /* SCTP_ZONE_FREE: free element from the zone */
 244 #define SCTP_ZONE_FREE(zone, element) \
 245         uma_zfree(zone, element);
 246
 247 #define SCTP_HASH_INIT(size, hashmark) hashinit_flags(size, M_PCB, hashmark, HASH_NOWAIT)
 248 #define SCTP_HASH_FREE(table, hashmark) hashdestroy(table, M_PCB, hashmark)
 249
 250 #define SCTP_M_COPYM    m_copym
 251
 252 /*
 253  * timers
 254  */
 255 #include <sys/callout.h>
 256 typedef struct callout sctp_os_timer_t;
 257
 258 #define SCTP_OS_TIMER_INIT(tmr) callout_init(tmr, 1)
 259 /*
 260  * NOTE: The next two shouldn't be called directly outside of sctp_timer_start()
 261  * and sctp_timer_stop(), since they don't handle incrementing/decrementing
 262  * relevant reference counts.
 263  */
 264 #define SCTP_OS_TIMER_START             callout_reset
 265 #define SCTP_OS_TIMER_STOP              callout_stop
 266 #define SCTP_OS_TIMER_STOP_DRAIN        callout_drain
 267 #define SCTP_OS_TIMER_PENDING           callout_pending
 268 #define SCTP_OS_TIMER_ACTIVE            callout_active
 269 #define SCTP_OS_TIMER_DEACTIVATE        callout_deactivate
 270
 271 #define sctp_get_tick_count() (ticks)
 272
 273 #define SCTP_UNUSED __attribute__((unused))
 274
 275 /*
 276  * Functions
 277  */
 278 /* Mbuf manipulation and access macros  */
 279 #define SCTP_BUF_LEN(m) (m->m_len)
 280 #define SCTP_BUF_NEXT(m) (m->m_next)
 281 #define SCTP_BUF_NEXT_PKT(m) (m->m_nextpkt)
 282 #define SCTP_BUF_RESV_UF(m, size) m->m_data += size
 283 #define SCTP_BUF_AT(m, size) m->m_data + size
 284 #define SCTP_BUF_IS_EXTENDED(m) (m->m_flags & M_EXT)
 285 #define SCTP_BUF_SIZE M_SIZE
 286 #define SCTP_BUF_TYPE(m) (m->m_type)
 287 #define SCTP_BUF_RECVIF(m) (m->m_pkthdr.rcvif)
 288 #define SCTP_BUF_PREPEND        M_PREPEND
 289
 290 #define SCTP_ALIGN_TO_END(m, len) M_ALIGN(m, len)
 291
 292 #define SCTP_SNPRINTF(...) snprintf(__VA_ARGS__)
 293
 294 /* We make it so if you have up to 4 threads
 295  * writing based on the default size of
 296  * the packet log 65 k, that would be
 297  * 4 16k packets before we would hit
 298  * a problem.
 299  */
 300 #define SCTP_PKTLOG_WRITERS_NEED_LOCK 3
 301
 302 /*************************/
 303 /*      MTU              */
 304 /*************************/
 305 #define SCTP_GATHER_MTU_FROM_IFN_INFO(ifn, ifn_index) ((ifn != NULL) ? ((struct ifnet *)ifn)->if_mtu : 0)
 306 #define SCTP_GATHER_MTU_FROM_ROUTE(sctp_ifa, sa, nh) ((uint32_t)((nh != NULL) ? nh->nh_mtu : 0))
 307
 308 /*************************/
 309 /* These are for logging */
 310 /*************************/
 311 /* return the base ext data pointer */
 312 #define SCTP_BUF_EXTEND_BASE(m) (m->m_ext.ext_buf)
 313  /* return the refcnt of the data pointer */
 314 #define SCTP_BUF_EXTEND_REFCNT(m) (*m->m_ext.ext_cnt)
 315 /* return any buffer related flags, this is
 316  * used beyond logging for apple only.
 317  */
 318 #define SCTP_BUF_GET_FLAGS(m) (m->m_flags)
 319
 320 /* For BSD this just accesses the M_PKTHDR length
 321  * so it operates on an mbuf with hdr flag. Other
 322  * O/S's may have separate packet header and mbuf
 323  * chain pointers.. thus the macro.
 324  */
 325 #define SCTP_HEADER_TO_CHAIN(m) (m)
 326 #define SCTP_DETACH_HEADER_FROM_CHAIN(m)
 327 #define SCTP_HEADER_LEN(m) ((m)->m_pkthdr.len)
 328 #define SCTP_GET_HEADER_FOR_OUTPUT(o_pak) 0
 329 #define SCTP_RELEASE_HEADER(m)
 330 #define SCTP_RELEASE_PKT(m)     sctp_m_freem(m)
 331 #define SCTP_ENABLE_UDP_CSUM(m) do { \
 332                                         m->m_pkthdr.csum_flags = CSUM_UDP; \
 333                                         m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); \
 334                                 } while (0)
 335
 336 #define SCTP_GET_PKT_VRFID(m, vrf_id)  ((vrf_id = SCTP_DEFAULT_VRFID) != SCTP_DEFAULT_VRFID)
 337
 338 /* Attach the chain of data into the sendable packet. */
 339 #define SCTP_ATTACH_CHAIN(pak, m, packet_length) do { \
 340                                                  pak = m; \
 341                                                  pak->m_pkthdr.len = packet_length; \
 342                          } while(0)
 343
 344 /* Other m_pkthdr type things */
 345 #define SCTP_IS_IT_BROADCAST(dst, m) ((m->m_flags & M_PKTHDR) ? in_broadcast(dst, m->m_pkthdr.rcvif) : 0)
 346 #define SCTP_IS_IT_LOOPBACK(m) ((m->m_flags & M_PKTHDR) && ((m->m_pkthdr.rcvif == NULL) || (m->m_pkthdr.rcvif->if_type == IFT_LOOP)))
 347
 348 /* This converts any input packet header
 349  * into the chain of data holders, for BSD
 350  * its a NOP.
 351  */
 352
 353 /* get the v6 hop limit */
 354 #define SCTP_GET_HLIM(inp, ro)  in6_selecthlim(&inp->ip_inp.inp, (ro ? (ro->ro_nh ? (ro->ro_nh->nh_ifp) : (NULL)) : (NULL)));
 355
 356 /* is the endpoint v6only? */
 357 #define SCTP_IPV6_V6ONLY(sctp_inpcb)    ((sctp_inpcb)->ip_inp.inp.inp_flags & IN6P_IPV6_V6ONLY)
 358 /* is the socket non-blocking? */
 359 #define SCTP_SO_IS_NBIO(so)     ((so)->so_state & SS_NBIO)
 360 #define SCTP_SET_SO_NBIO(so)    ((so)->so_state |= SS_NBIO)
 361 #define SCTP_CLEAR_SO_NBIO(so)  ((so)->so_state &= ~SS_NBIO)
 362 /* get the socket type */
 363 #define SCTP_SO_TYPE(so)        ((so)->so_type)
 364 /* reserve sb space for a socket */
 365 #define SCTP_SORESERVE(so, send, recv)  soreserve(so, send, recv)
 366 /* wakeup a socket */
 367 #define SCTP_SOWAKEUP(so)       wakeup(&(so)->so_timeo)
 368 /* number of bytes ready to read */
 369 #define SCTP_SBAVAIL(sb)        sbavail(sb)
 370 /* clear the socket buffer state */
 371 #define SCTP_SB_INCR(sb, incr)                  \
 372 {                                               \
 373         atomic_add_int(&(sb)->sb_acc, incr);    \
 374         atomic_add_int(&(sb)->sb_ccc, incr);    \
 375 }
 376 #define SCTP_SB_DECR(sb, decr)                                  \
 377 {                                                               \
 378         SCTP_SAVE_ATOMIC_DECREMENT(&(sb)->sb_acc, decr);        \
 379         SCTP_SAVE_ATOMIC_DECREMENT(&(sb)->sb_ccc, decr);        \
 380 }
 381 #define SCTP_SB_CLEAR(sb)       \
 382         (sb).sb_acc = 0;        \
 383         (sb).sb_ccc = 0;        \
 384         (sb).sb_mb = NULL;      \
 385         (sb).sb_mbcnt = 0;
 386
 387 #define SCTP_SB_LIMIT_RCV(so) (SOLISTENING(so) ? so->sol_sbrcv_hiwat : so->so_rcv.sb_hiwat)
 388 #define SCTP_SB_LIMIT_SND(so) (SOLISTENING(so) ? so->sol_sbsnd_hiwat : so->so_snd.sb_hiwat)
 389
 390 /*
 391  * routes, output, etc.
 392  */
 393 typedef struct route sctp_route_t;
 394
 395 #define SCTP_RTALLOC(ro, vrf_id, fibnum) \
 396 { \
 397         if ((ro)->ro_nh == NULL) { \
 398                 (ro)->ro_nh = rib_lookup(fibnum, &(ro)->ro_dst, NHR_REF, 0); \
 399         } \
 400 }
 401
 402 /*
 403  * SCTP protocol specific mbuf flags.
 404  */
 405 #define M_NOTIFICATION          M_PROTO1        /* SCTP notification */
 406
 407 /*
 408  * IP output routines
 409  */
 410 #define SCTP_IP_OUTPUT(result, o_pak, ro, _inp, vrf_id)                      \
 411 {                                                                            \
 412         struct sctp_inpcb *local_inp = _inp;                                 \
 413         int o_flgs = IP_RAWOUTPUT;                                           \
 414                                                                              \
 415         m_clrprotoflags(o_pak);                                              \
 416         if ((local_inp != NULL) && (local_inp->sctp_socket != NULL)) {       \
 417                 o_flgs |= local_inp->sctp_socket->so_options & SO_DONTROUTE; \
 418         }                                                                    \
 419         result = ip_output(o_pak, NULL, ro, o_flgs, 0, NULL);                \
 420 }
 421
 422 #define SCTP_IP6_OUTPUT(result, o_pak, ro, ifp, _inp, vrf_id)                \
 423 {                                                                            \
 424         struct sctp_inpcb *local_inp = _inp;                                 \
 425                                                                              \
 426         m_clrprotoflags(o_pak);                                              \
 427         if (local_inp != NULL) {                                             \
 428                 INP_RLOCK(&local_inp->ip_inp.inp);                           \
 429                 result = ip6_output(o_pak,                                   \
 430                                     local_inp->ip_inp.inp.in6p_outputopts,   \
 431                                     (ro), 0, 0, ifp, NULL);                  \
 432                 INP_RUNLOCK(&local_inp->ip_inp.inp);                         \
 433         } else {                                                             \
 434                 result = ip6_output(o_pak, NULL, (ro), 0, 0, ifp, NULL);     \
 435         }                                                                    \
 436 }
 437
 438 struct mbuf *
 439 sctp_get_mbuf_for_msg(unsigned int space_needed,
 440     int want_header, int how, int allonebuf, int type);
 441
 442 /*
 443  * SCTP AUTH
 444  */
 445 #define SCTP_READ_RANDOM(buf, len)      arc4rand(buf, len, 0)
 446
 447 /* map standard crypto API names */
 448 #define SCTP_SHA1_CTX           SHA1_CTX
 449 #define SCTP_SHA1_INIT          SHA1Init
 450 #define SCTP_SHA1_UPDATE        SHA1Update
 451 #define SCTP_SHA1_FINAL(x,y)    SHA1Final((caddr_t)x, y)
 452
 453 #define SCTP_SHA256_CTX         SHA256_CTX
 454 #define SCTP_SHA256_INIT        SHA256_Init
 455 #define SCTP_SHA256_UPDATE      SHA256_Update
 456 #define SCTP_SHA256_FINAL(x,y)  SHA256_Final((caddr_t)x, y)
 457
 458 #define SCTP_DECREMENT_AND_CHECK_REFCOUNT(addr) (atomic_fetchadd_int(addr, -1) == 1)
 459 #if defined(INVARIANTS)
 460 #define SCTP_SAVE_ATOMIC_DECREMENT(addr, val) \
 461 { \
 462         int32_t oldval; \
 463         oldval = atomic_fetchadd_int(addr, -val); \
 464         if (oldval < val) { \
 465                 panic("Counter goes negative"); \
 466         } \
 467 }
 468 #else
 469 #define SCTP_SAVE_ATOMIC_DECREMENT(addr, val) \
 470 { \
 471         int32_t oldval; \
 472         oldval = atomic_fetchadd_int(addr, -val); \
 473         if (oldval < val) { \
 474                 *addr = 0; \
 475         } \
 476 }
 477 #endif
 478
 479 #define SCTP_IS_LISTENING(inp) ((inp->sctp_flags & SCTP_PCB_FLAGS_ACCEPTING) != 0)
 480
 481 int sctp_syscalls_init(void);
 482 int sctp_syscalls_uninit(void);
 483
 484 #endif