sys/netinet/udp_usrreq.c

   1 /*-
   2  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
   3  *      The Regents of the University of California.
   4  * Copyright (c) 2008 Robert N. M. Watson
   5  * Copyright (c) 2010-2011 Juniper Networks, Inc.
   6  * Copyright (c) 2014 Kevin Lo
   7  * All rights reserved.
   8  *
   9  * Portions of this software were developed by Robert N. M. Watson under
  10  * contract to Juniper Networks, Inc.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  *      @(#)udp_usrreq.c        8.6 (Berkeley) 5/23/95
  37  */
  38
  39 #include <sys/cdefs.h>
  40 __FBSDID("$FreeBSD$");
  41
  42 #include "opt_inet.h"
  43 #include "opt_inet6.h"
  44 #include "opt_ipsec.h"
  45 #include "opt_rss.h"
  46
  47 #include <sys/param.h>
  48 #include <sys/domain.h>
  49 #include <sys/eventhandler.h>
  50 #include <sys/jail.h>
  51 #include <sys/kernel.h>
  52 #include <sys/lock.h>
  53 #include <sys/malloc.h>
  54 #include <sys/mbuf.h>
  55 #include <sys/priv.h>
  56 #include <sys/proc.h>
  57 #include <sys/protosw.h>
  58 #include <sys/sdt.h>
  59 #include <sys/signalvar.h>
  60 #include <sys/socket.h>
  61 #include <sys/socketvar.h>
  62 #include <sys/sx.h>
  63 #include <sys/sysctl.h>
  64 #include <sys/syslog.h>
  65 #include <sys/systm.h>
  66
  67 #include <vm/uma.h>
  68
  69 #include <net/if.h>
  70 #include <net/if_var.h>
  71 #include <net/route.h>
  72 #include <net/rss_config.h>
  73
  74 #include <netinet/in.h>
  75 #include <netinet/in_kdtrace.h>
  76 #include <netinet/in_pcb.h>
  77 #include <netinet/in_systm.h>
  78 #include <netinet/in_var.h>
  79 #include <netinet/ip.h>
  80 #ifdef INET6
  81 #include <netinet/ip6.h>
  82 #endif
  83 #include <netinet/ip_icmp.h>
  84 #include <netinet/icmp_var.h>
  85 #include <netinet/ip_var.h>
  86 #include <netinet/ip_options.h>
  87 #ifdef INET6
  88 #include <netinet6/ip6_var.h>
  89 #endif
  90 #include <netinet/udp.h>
  91 #include <netinet/udp_var.h>
  92 #include <netinet/udplite.h>
  93 #include <netinet/in_rss.h>
  94
  95 #include <netipsec/ipsec_support.h>
  96
  97 #include <machine/in_cksum.h>
  98
  99 #include <security/mac/mac_framework.h>
 100
 101 /*
 102  * UDP and UDP-Lite protocols implementation.
 103  * Per RFC 768, August, 1980.
 104  * Per RFC 3828, July, 2004.
 105  */
 106
 107 /*
 108  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
 109  * removes the only data integrity mechanism for packets and malformed
 110  * packets that would otherwise be discarded due to bad checksums, and may
 111  * cause problems (especially for NFS data blocks).
 112  */
 113 VNET_DEFINE(int, udp_cksum) = 1;
 114 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
 115     &VNET_NAME(udp_cksum), 0, "compute udp checksum");
 116
 117 int     udp_log_in_vain = 0;
 118 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW,
 119     &udp_log_in_vain, 0, "Log all incoming UDP packets");
 120
 121 VNET_DEFINE(int, udp_blackhole) = 0;
 122 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
 123     &VNET_NAME(udp_blackhole), 0,
 124     "Do not send port unreachables for refused connects");
 125
 126 static VNET_DEFINE(int, udp_require_l2_bcast) = 0;
 127 #define V_udp_require_l2_bcast          VNET(udp_require_l2_bcast)
 128 SYSCTL_INT(_net_inet_udp, OID_AUTO, require_l2_bcast, CTLFLAG_VNET | CTLFLAG_RW,
 129     &VNET_NAME(udp_require_l2_bcast), 0,
 130     "Only treat packets sent to an L2 broadcast address as broadcast packets");
 131
 132 u_long  udp_sendspace = 9216;           /* really max datagram size */
 133 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
 134     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
 135
 136 u_long  udp_recvspace = 40 * (1024 +
 137 #ifdef INET6
 138                                       sizeof(struct sockaddr_in6)
 139 #else
 140                                       sizeof(struct sockaddr_in)
 141 #endif
 142                                       );        /* 40 1K datagrams */
 143
 144 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
 145     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
 146
 147 VNET_DEFINE(struct inpcbhead, udb);             /* from udp_var.h */
 148 VNET_DEFINE(struct inpcbinfo, udbinfo);
 149 VNET_DEFINE(struct inpcbhead, ulitecb);
 150 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
 151 static VNET_DEFINE(uma_zone_t, udpcb_zone);
 152 #define V_udpcb_zone                    VNET(udpcb_zone)
 153
 154 #ifndef UDBHASHSIZE
 155 #define UDBHASHSIZE     128
 156 #endif
 157
 158 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat);          /* from udp_var.h */
 159 VNET_PCPUSTAT_SYSINIT(udpstat);
 160 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
 161     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
 162
 163 #ifdef VIMAGE
 164 VNET_PCPUSTAT_SYSUNINIT(udpstat);
 165 #endif /* VIMAGE */
 166 #ifdef INET
 167 static void     udp_detach(struct socket *so);
 168 static int      udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
 169                     struct mbuf *, struct thread *);
 170 #endif
 171
 172 static void
 173 udp_zone_change(void *tag)
 174 {
 175
 176         uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
 177         uma_zone_set_max(V_udpcb_zone, maxsockets);
 178 }
 179
 180 static int
 181 udp_inpcb_init(void *mem, int size, int flags)
 182 {
 183         struct inpcb *inp;
 184
 185         inp = mem;
 186         INP_LOCK_INIT(inp, "inp", "udpinp");
 187         return (0);
 188 }
 189
 190 static int
 191 udplite_inpcb_init(void *mem, int size, int flags)
 192 {
 193         struct inpcb *inp;
 194
 195         inp = mem;
 196         INP_LOCK_INIT(inp, "inp", "udpliteinp");
 197         return (0);
 198 }
 199
 200 void
 201 udp_init(void)
 202 {
 203
 204         /*
 205          * For now default to 2-tuple UDP hashing - until the fragment
 206          * reassembly code can also update the flowid.
 207          *
 208          * Once we can calculate the flowid that way and re-establish
 209          * a 4-tuple, flip this to 4-tuple.
 210          */
 211         in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE,
 212             "udp_inpcb", udp_inpcb_init, NULL, 0,
 213             IPI_HASHFIELDS_2TUPLE);
 214         V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb),
 215             NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
 216         uma_zone_set_max(V_udpcb_zone, maxsockets);
 217         uma_zone_set_warning(V_udpcb_zone, "kern.ipc.maxsockets limit reached");
 218         EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL,
 219             EVENTHANDLER_PRI_ANY);
 220 }
 221
 222 void
 223 udplite_init(void)
 224 {
 225
 226         in_pcbinfo_init(&V_ulitecbinfo, "udplite", &V_ulitecb, UDBHASHSIZE,
 227             UDBHASHSIZE, "udplite_inpcb", udplite_inpcb_init, NULL,
 228             0, IPI_HASHFIELDS_2TUPLE);
 229 }
 230
 231 /*
 232  * Kernel module interface for updating udpstat.  The argument is an index
 233  * into udpstat treated as an array of u_long.  While this encodes the
 234  * general layout of udpstat into the caller, it doesn't encode its location,
 235  * so that future changes to add, for example, per-CPU stats support won't
 236  * cause binary compatibility problems for kernel modules.
 237  */
 238 void
 239 kmod_udpstat_inc(int statnum)
 240 {
 241
 242         counter_u64_add(VNET(udpstat)[statnum], 1);
 243 }
 244
 245 int
 246 udp_newudpcb(struct inpcb *inp)
 247 {
 248         struct udpcb *up;
 249
 250         up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO);
 251         if (up == NULL)
 252                 return (ENOBUFS);
 253         inp->inp_ppcb = up;
 254         return (0);
 255 }
 256
 257 void
 258 udp_discardcb(struct udpcb *up)
 259 {
 260
 261         uma_zfree(V_udpcb_zone, up);
 262 }
 263
 264 #ifdef VIMAGE
 265 static void
 266 udp_destroy(void *unused __unused)
 267 {
 268
 269         in_pcbinfo_destroy(&V_udbinfo);
 270         uma_zdestroy(V_udpcb_zone);
 271 }
 272 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
 273
 274 static void
 275 udplite_destroy(void *unused __unused)
 276 {
 277
 278         in_pcbinfo_destroy(&V_ulitecbinfo);
 279 }
 280 VNET_SYSUNINIT(udplite, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udplite_destroy,
 281     NULL);
 282 #endif
 283
 284 #ifdef INET
 285 /*
 286  * Subroutine of udp_input(), which appends the provided mbuf chain to the
 287  * passed pcb/socket.  The caller must provide a sockaddr_in via udp_in that
 288  * contains the source address.  If the socket ends up being an IPv6 socket,
 289  * udp_append() will convert to a sockaddr_in6 before passing the address
 290  * into the socket code.
 291  *
 292  * In the normal case udp_append() will return 0, indicating that you
 293  * must unlock the inp. However if a tunneling protocol is in place we increment
 294  * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
 295  * then decrement the reference count. If the inp_rele returns 1, indicating the
 296  * inp is gone, we return that to the caller to tell them *not* to unlock
 297  * the inp. In the case of multi-cast this will cause the distribution
 298  * to stop (though most tunneling protocols known currently do *not* use
 299  * multicast).
 300  */
 301 static int
 302 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
 303     struct sockaddr_in *udp_in)
 304 {
 305         struct sockaddr *append_sa;
 306         struct socket *so;
 307         struct mbuf *tmpopts, *opts = NULL;
 308 #ifdef INET6
 309         struct sockaddr_in6 udp_in6;
 310 #endif
 311         struct udpcb *up;
 312
 313         INP_LOCK_ASSERT(inp);
 314
 315         /*
 316          * Engage the tunneling protocol.
 317          */
 318         up = intoudpcb(inp);
 319         if (up->u_tun_func != NULL) {
 320                 in_pcbref(inp);
 321                 INP_RUNLOCK(inp);
 322                 (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
 323                     up->u_tun_ctx);
 324                 INP_RLOCK(inp);
 325                 return (in_pcbrele_rlocked(inp));
 326         }
 327
 328         off += sizeof(struct udphdr);
 329
 330 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 331         /* Check AH/ESP integrity. */
 332         if (IPSEC_ENABLED(ipv4) &&
 333             IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
 334                 m_freem(n);
 335                 return (0);
 336         }
 337         if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
 338                 if (IPSEC_ENABLED(ipv4) &&
 339                     UDPENCAP_INPUT(n, off, AF_INET) != 0)
 340                         return (0);     /* Consumed. */
 341         }
 342 #endif /* IPSEC */
 343 #ifdef MAC
 344         if (mac_inpcb_check_deliver(inp, n) != 0) {
 345                 m_freem(n);
 346                 return (0);
 347         }
 348 #endif /* MAC */
 349         if (inp->inp_flags & INP_CONTROLOPTS ||
 350             inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
 351 #ifdef INET6
 352                 if (inp->inp_vflag & INP_IPV6)
 353                         (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
 354                 else
 355 #endif /* INET6 */
 356                         ip_savecontrol(inp, &opts, ip, n);
 357         }
 358         if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
 359                 tmpopts = sbcreatecontrol((caddr_t)&udp_in[1],
 360                         sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP);
 361                 if (tmpopts) {
 362                         if (opts) {
 363                                 tmpopts->m_next = opts;
 364                                 opts = tmpopts;
 365                         } else
 366                                 opts = tmpopts;
 367                 }
 368         }
 369 #ifdef INET6
 370         if (inp->inp_vflag & INP_IPV6) {
 371                 bzero(&udp_in6, sizeof(udp_in6));
 372                 udp_in6.sin6_len = sizeof(udp_in6);
 373                 udp_in6.sin6_family = AF_INET6;
 374                 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
 375                 append_sa = (struct sockaddr *)&udp_in6;
 376         } else
 377 #endif /* INET6 */
 378                 append_sa = (struct sockaddr *)&udp_in[0];
 379         m_adj(n, off);
 380
 381         so = inp->inp_socket;
 382         SOCKBUF_LOCK(&so->so_rcv);
 383         if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
 384                 SOCKBUF_UNLOCK(&so->so_rcv);
 385                 m_freem(n);
 386                 if (opts)
 387                         m_freem(opts);
 388                 UDPSTAT_INC(udps_fullsock);
 389         } else
 390                 sorwakeup_locked(so);
 391         return (0);
 392 }
 393
 394 int
 395 udp_input(struct mbuf **mp, int *offp, int proto)
 396 {
 397         struct ip *ip;
 398         struct udphdr *uh;
 399         struct ifnet *ifp;
 400         struct inpcb *inp;
 401         uint16_t len, ip_len;
 402         struct inpcbinfo *pcbinfo;
 403         struct ip save_ip;
 404         struct sockaddr_in udp_in[2];
 405         struct mbuf *m;
 406         struct m_tag *fwd_tag;
 407         int cscov_partial, iphlen;
 408
 409         m = *mp;
 410         iphlen = *offp;
 411         ifp = m->m_pkthdr.rcvif;
 412         *mp = NULL;
 413         UDPSTAT_INC(udps_ipackets);
 414
 415         /*
 416          * Strip IP options, if any; should skip this, make available to
 417          * user, and use on returned packets, but we don't yet have a way to
 418          * check the checksum with options still present.
 419          */
 420         if (iphlen > sizeof (struct ip)) {
 421                 ip_stripoptions(m);
 422                 iphlen = sizeof(struct ip);
 423         }
 424
 425         /*
 426          * Get IP and UDP header together in first mbuf.
 427          */
 428         ip = mtod(m, struct ip *);
 429         if (m->m_len < iphlen + sizeof(struct udphdr)) {
 430                 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
 431                         UDPSTAT_INC(udps_hdrops);
 432                         return (IPPROTO_DONE);
 433                 }
 434                 ip = mtod(m, struct ip *);
 435         }
 436         uh = (struct udphdr *)((caddr_t)ip + iphlen);
 437         cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
 438
 439         /*
 440          * Destination port of 0 is illegal, based on RFC768.
 441          */
 442         if (uh->uh_dport == 0)
 443                 goto badunlocked;
 444
 445         /*
 446          * Construct sockaddr format source address.  Stuff source address
 447          * and datagram in user buffer.
 448          */
 449         bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
 450         udp_in[0].sin_len = sizeof(struct sockaddr_in);
 451         udp_in[0].sin_family = AF_INET;
 452         udp_in[0].sin_port = uh->uh_sport;
 453         udp_in[0].sin_addr = ip->ip_src;
 454         udp_in[1].sin_len = sizeof(struct sockaddr_in);
 455         udp_in[1].sin_family = AF_INET;
 456         udp_in[1].sin_port = uh->uh_dport;
 457         udp_in[1].sin_addr = ip->ip_dst;
 458
 459         /*
 460          * Make mbuf data length reflect UDP length.  If not enough data to
 461          * reflect UDP length, drop.
 462          */
 463         len = ntohs((u_short)uh->uh_ulen);
 464         ip_len = ntohs(ip->ip_len) - iphlen;
 465         if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
 466                 /* Zero means checksum over the complete packet. */
 467                 if (len == 0)
 468                         len = ip_len;
 469                 cscov_partial = 0;
 470         }
 471         if (ip_len != len) {
 472                 if (len > ip_len || len < sizeof(struct udphdr)) {
 473                         UDPSTAT_INC(udps_badlen);
 474                         goto badunlocked;
 475                 }
 476                 if (proto == IPPROTO_UDP)
 477                         m_adj(m, len - ip_len);
 478         }
 479
 480         /*
 481          * Save a copy of the IP header in case we want restore it for
 482          * sending an ICMP error message in response.
 483          */
 484         if (!V_udp_blackhole)
 485                 save_ip = *ip;
 486         else
 487                 memset(&save_ip, 0, sizeof(save_ip));
 488
 489         /*
 490          * Checksum extended UDP header and data.
 491          */
 492         if (uh->uh_sum) {
 493                 u_short uh_sum;
 494
 495                 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
 496                     !cscov_partial) {
 497                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 498                                 uh_sum = m->m_pkthdr.csum_data;
 499                         else
 500                                 uh_sum = in_pseudo(ip->ip_src.s_addr,
 501                                     ip->ip_dst.s_addr, htonl((u_short)len +
 502                                     m->m_pkthdr.csum_data + proto));
 503                         uh_sum ^= 0xffff;
 504                 } else {
 505                         char b[9];
 506
 507                         bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
 508                         bzero(((struct ipovly *)ip)->ih_x1, 9);
 509                         ((struct ipovly *)ip)->ih_len = (proto == IPPROTO_UDP) ?
 510                             uh->uh_ulen : htons(ip_len);
 511                         uh_sum = in_cksum(m, len + sizeof (struct ip));
 512                         bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
 513                 }
 514                 if (uh_sum) {
 515                         UDPSTAT_INC(udps_badsum);
 516                         m_freem(m);
 517                         return (IPPROTO_DONE);
 518                 }
 519         } else {
 520                 if (proto == IPPROTO_UDP) {
 521                         UDPSTAT_INC(udps_nosum);
 522                 } else {
 523                         /* UDPLite requires a checksum */
 524                         /* XXX: What is the right UDPLite MIB counter here? */
 525                         m_freem(m);
 526                         return (IPPROTO_DONE);
 527                 }
 528         }
 529
 530         pcbinfo = udp_get_inpcbinfo(proto);
 531         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
 532             ((!V_udp_require_l2_bcast || m->m_flags & M_BCAST) &&
 533             in_broadcast(ip->ip_dst, ifp))) {
 534                 struct inpcb *last;
 535                 struct inpcbhead *pcblist;
 536                 struct ip_moptions *imo;
 537
 538                 INP_INFO_RLOCK(pcbinfo);
 539                 pcblist = udp_get_pcblist(proto);
 540                 last = NULL;
 541                 LIST_FOREACH(inp, pcblist, inp_list) {
 542                         if (inp->inp_lport != uh->uh_dport)
 543                                 continue;
 544 #ifdef INET6
 545                         if ((inp->inp_vflag & INP_IPV4) == 0)
 546                                 continue;
 547 #endif
 548                         if (inp->inp_laddr.s_addr != INADDR_ANY &&
 549                             inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
 550                                 continue;
 551                         if (inp->inp_faddr.s_addr != INADDR_ANY &&
 552                             inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 553                                 continue;
 554                         if (inp->inp_fport != 0 &&
 555                             inp->inp_fport != uh->uh_sport)
 556                                 continue;
 557
 558                         INP_RLOCK(inp);
 559
 560                         /*
 561                          * XXXRW: Because we weren't holding either the inpcb
 562                          * or the hash lock when we checked for a match
 563                          * before, we should probably recheck now that the
 564                          * inpcb lock is held.
 565                          */
 566
 567                         /*
 568                          * Handle socket delivery policy for any-source
 569                          * and source-specific multicast. [RFC3678]
 570                          */
 571                         imo = inp->inp_moptions;
 572                         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 573                                 struct sockaddr_in       group;
 574                                 int                      blocked;
 575                                 if (imo == NULL) {
 576                                         INP_RUNLOCK(inp);
 577                                         continue;
 578                                 }
 579                                 bzero(&group, sizeof(struct sockaddr_in));
 580                                 group.sin_len = sizeof(struct sockaddr_in);
 581                                 group.sin_family = AF_INET;
 582                                 group.sin_addr = ip->ip_dst;
 583
 584                                 blocked = imo_multi_filter(imo, ifp,
 585                                         (struct sockaddr *)&group,
 586                                         (struct sockaddr *)&udp_in[0]);
 587                                 if (blocked != MCAST_PASS) {
 588                                         if (blocked == MCAST_NOTGMEMBER)
 589                                                 IPSTAT_INC(ips_notmember);
 590                                         if (blocked == MCAST_NOTSMEMBER ||
 591                                             blocked == MCAST_MUTED)
 592                                                 UDPSTAT_INC(udps_filtermcast);
 593                                         INP_RUNLOCK(inp);
 594                                         continue;
 595                                 }
 596                         }
 597                         if (last != NULL) {
 598                                 struct mbuf *n;
 599
 600                                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) !=
 601                                     NULL) {
 602                                         UDP_PROBE(receive, NULL, last, ip,
 603                                             last, uh);
 604                                         if (udp_append(last, ip, n, iphlen,
 605                                                 udp_in)) {
 606                                                 goto inp_lost;
 607                                         }
 608                                 }
 609                                 INP_RUNLOCK(last);
 610                         }
 611                         last = inp;
 612                         /*
 613                          * Don't look for additional matches if this one does
 614                          * not have either the SO_REUSEPORT or SO_REUSEADDR
 615                          * socket options set.  This heuristic avoids
 616                          * searching through all pcbs in the common case of a
 617                          * non-shared port.  It assumes that an application
 618                          * will never clear these options after setting them.
 619                          */
 620                         if ((last->inp_socket->so_options &
 621                             (SO_REUSEPORT|SO_REUSEADDR)) == 0)
 622                                 break;
 623                 }
 624
 625                 if (last == NULL) {
 626                         /*
 627                          * No matching pcb found; discard datagram.  (No need
 628                          * to send an ICMP Port Unreachable for a broadcast
 629                          * or multicast datgram.)
 630                          */
 631                         UDPSTAT_INC(udps_noportbcast);
 632                         if (inp)
 633                                 INP_RUNLOCK(inp);
 634                         INP_INFO_RUNLOCK(pcbinfo);
 635                         goto badunlocked;
 636                 }
 637                 UDP_PROBE(receive, NULL, last, ip, last, uh);
 638                 if (udp_append(last, ip, m, iphlen, udp_in) == 0)
 639                         INP_RUNLOCK(last);
 640         inp_lost:
 641                 INP_INFO_RUNLOCK(pcbinfo);
 642                 return (IPPROTO_DONE);
 643         }
 644
 645         /*
 646          * Locate pcb for datagram.
 647          */
 648
 649         /*
 650          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 651          */
 652         if ((m->m_flags & M_IP_NEXTHOP) &&
 653             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 654                 struct sockaddr_in *next_hop;
 655
 656                 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
 657
 658                 /*
 659                  * Transparently forwarded. Pretend to be the destination.
 660                  * Already got one like this?
 661                  */
 662                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 663                     ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
 664                 if (!inp) {
 665                         /*
 666                          * It's new.  Try to find the ambushing socket.
 667                          * Because we've rewritten the destination address,
 668                          * any hardware-generated hash is ignored.
 669                          */
 670                         inp = in_pcblookup(pcbinfo, ip->ip_src,
 671                             uh->uh_sport, next_hop->sin_addr,
 672                             next_hop->sin_port ? htons(next_hop->sin_port) :
 673                             uh->uh_dport, INPLOOKUP_WILDCARD |
 674                             INPLOOKUP_RLOCKPCB, ifp);
 675                 }
 676                 /* Remove the tag from the packet. We don't need it anymore. */
 677                 m_tag_delete(m, fwd_tag);
 678                 m->m_flags &= ~M_IP_NEXTHOP;
 679         } else
 680                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 681                     ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
 682                     INPLOOKUP_RLOCKPCB, ifp, m);
 683         if (inp == NULL) {
 684                 if (udp_log_in_vain) {
 685                         char src[INET_ADDRSTRLEN];
 686                         char dst[INET_ADDRSTRLEN];
 687
 688                         log(LOG_INFO,
 689                             "Connection attempt to UDP %s:%d from %s:%d\n",
 690                             inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
 691                             inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
 692                 }
 693                 UDPSTAT_INC(udps_noport);
 694                 if (m->m_flags & (M_BCAST | M_MCAST)) {
 695                         UDPSTAT_INC(udps_noportbcast);
 696                         goto badunlocked;
 697                 }
 698                 if (V_udp_blackhole)
 699                         goto badunlocked;
 700                 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
 701                         goto badunlocked;
 702                 *ip = save_ip;
 703                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
 704                 return (IPPROTO_DONE);
 705         }
 706
 707         /*
 708          * Check the minimum TTL for socket.
 709          */
 710         INP_RLOCK_ASSERT(inp);
 711         if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
 712                 INP_RUNLOCK(inp);
 713                 m_freem(m);
 714                 return (IPPROTO_DONE);
 715         }
 716         if (cscov_partial) {
 717                 struct udpcb *up;
 718
 719                 up = intoudpcb(inp);
 720                 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
 721                         INP_RUNLOCK(inp);
 722                         m_freem(m);
 723                         return (IPPROTO_DONE);
 724                 }
 725         }
 726
 727         UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 728         if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
 729                 INP_RUNLOCK(inp);
 730         return (IPPROTO_DONE);
 731
 732 badunlocked:
 733         m_freem(m);
 734         return (IPPROTO_DONE);
 735 }
 736 #endif /* INET */
 737
 738 /*
 739  * Notify a udp user of an asynchronous error; just wake up so that they can
 740  * collect error status.
 741  */
 742 struct inpcb *
 743 udp_notify(struct inpcb *inp, int errno)
 744 {
 745
 746         /*
 747          * While udp_ctlinput() always calls udp_notify() with a read lock
 748          * when invoking it directly, in_pcbnotifyall() currently uses write
 749          * locks due to sharing code with TCP.  For now, accept either a read
 750          * or a write lock, but a read lock is sufficient.
 751          */
 752         INP_LOCK_ASSERT(inp);
 753         if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
 754              errno == EHOSTDOWN) && inp->inp_route.ro_rt) {
 755                 RTFREE(inp->inp_route.ro_rt);
 756                 inp->inp_route.ro_rt = (struct rtentry *)NULL;
 757         }
 758
 759         inp->inp_socket->so_error = errno;
 760         sorwakeup(inp->inp_socket);
 761         sowwakeup(inp->inp_socket);
 762         return (inp);
 763 }
 764
 765 #ifdef INET
 766 static void
 767 udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip,
 768     struct inpcbinfo *pcbinfo)
 769 {
 770         struct ip *ip = vip;
 771         struct udphdr *uh;
 772         struct in_addr faddr;
 773         struct inpcb *inp;
 774
 775         faddr = ((struct sockaddr_in *)sa)->sin_addr;
 776         if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
 777                 return;
 778
 779         if (PRC_IS_REDIRECT(cmd)) {
 780                 /* signal EHOSTDOWN, as it flushes the cached route */
 781                 in_pcbnotifyall(&V_udbinfo, faddr, EHOSTDOWN, udp_notify);
 782                 return;
 783         }
 784
 785         /*
 786          * Hostdead is ugly because it goes linearly through all PCBs.
 787          *
 788          * XXX: We never get this from ICMP, otherwise it makes an excellent
 789          * DoS attack on machines with many connections.
 790          */
 791         if (cmd == PRC_HOSTDEAD)
 792                 ip = NULL;
 793         else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
 794                 return;
 795         if (ip != NULL) {
 796                 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 797                 inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 798                     ip->ip_src, uh->uh_sport, INPLOOKUP_RLOCKPCB, NULL);
 799                 if (inp != NULL) {
 800                         INP_RLOCK_ASSERT(inp);
 801                         if (inp->inp_socket != NULL) {
 802                                 udp_notify(inp, inetctlerrmap[cmd]);
 803                         }
 804                         INP_RUNLOCK(inp);
 805                 } else {
 806                         inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 807                                            ip->ip_src, uh->uh_sport,
 808                                            INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 809                         if (inp != NULL) {
 810                                 struct udpcb *up;
 811
 812                                 up = intoudpcb(inp);
 813                                 if (up->u_icmp_func != NULL) {
 814                                         INP_RUNLOCK(inp);
 815                                         (*up->u_icmp_func)(cmd, sa, vip, up->u_tun_ctx);
 816                                 } else {
 817                                         INP_RUNLOCK(inp);
 818                                 }
 819                         }
 820                 }
 821         } else
 822                 in_pcbnotifyall(pcbinfo, faddr, inetctlerrmap[cmd],
 823                     udp_notify);
 824 }
 825 void
 826 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 827 {
 828
 829         return (udp_common_ctlinput(cmd, sa, vip, &V_udbinfo));
 830 }
 831
 832 void
 833 udplite_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 834 {
 835
 836         return (udp_common_ctlinput(cmd, sa, vip, &V_ulitecbinfo));
 837 }
 838 #endif /* INET */
 839
 840 static int
 841 udp_pcblist(SYSCTL_HANDLER_ARGS)
 842 {
 843         int error, i, n;
 844         struct inpcb *inp, **inp_list;
 845         inp_gen_t gencnt;
 846         struct xinpgen xig;
 847
 848         /*
 849          * The process of preparing the PCB list is too time-consuming and
 850          * resource-intensive to repeat twice on every request.
 851          */
 852         if (req->oldptr == 0) {
 853                 n = V_udbinfo.ipi_count;
 854                 n += imax(n / 8, 10);
 855                 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
 856                 return (0);
 857         }
 858
 859         if (req->newptr != 0)
 860                 return (EPERM);
 861
 862         /*
 863          * OK, now we're committed to doing something.
 864          */
 865         INP_INFO_RLOCK(&V_udbinfo);
 866         gencnt = V_udbinfo.ipi_gencnt;
 867         n = V_udbinfo.ipi_count;
 868         INP_INFO_RUNLOCK(&V_udbinfo);
 869
 870         error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
 871                 + n * sizeof(struct xinpcb));
 872         if (error != 0)
 873                 return (error);
 874
 875         xig.xig_len = sizeof xig;
 876         xig.xig_count = n;
 877         xig.xig_gen = gencnt;
 878         xig.xig_sogen = so_gencnt;
 879         error = SYSCTL_OUT(req, &xig, sizeof xig);
 880         if (error)
 881                 return (error);
 882
 883         inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
 884         if (inp_list == NULL)
 885                 return (ENOMEM);
 886
 887         INP_INFO_RLOCK(&V_udbinfo);
 888         for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n;
 889              inp = LIST_NEXT(inp, inp_list)) {
 890                 INP_WLOCK(inp);
 891                 if (inp->inp_gencnt <= gencnt &&
 892                     cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
 893                         in_pcbref(inp);
 894                         inp_list[i++] = inp;
 895                 }
 896                 INP_WUNLOCK(inp);
 897         }
 898         INP_INFO_RUNLOCK(&V_udbinfo);
 899         n = i;
 900
 901         error = 0;
 902         for (i = 0; i < n; i++) {
 903                 inp = inp_list[i];
 904                 INP_RLOCK(inp);
 905                 if (inp->inp_gencnt <= gencnt) {
 906                         struct xinpcb xi;
 907
 908                         in_pcbtoxinpcb(inp, &xi);
 909                         INP_RUNLOCK(inp);
 910                         error = SYSCTL_OUT(req, &xi, sizeof xi);
 911                 } else
 912                         INP_RUNLOCK(inp);
 913         }
 914         INP_INFO_WLOCK(&V_udbinfo);
 915         for (i = 0; i < n; i++) {
 916                 inp = inp_list[i];
 917                 INP_RLOCK(inp);
 918                 if (!in_pcbrele_rlocked(inp))
 919                         INP_RUNLOCK(inp);
 920         }
 921         INP_INFO_WUNLOCK(&V_udbinfo);
 922
 923         if (!error) {
 924                 /*
 925                  * Give the user an updated idea of our state.  If the
 926                  * generation differs from what we told her before, she knows
 927                  * that something happened while we were processing this
 928                  * request, and it might be necessary to retry.
 929                  */
 930                 INP_INFO_RLOCK(&V_udbinfo);
 931                 xig.xig_gen = V_udbinfo.ipi_gencnt;
 932                 xig.xig_sogen = so_gencnt;
 933                 xig.xig_count = V_udbinfo.ipi_count;
 934                 INP_INFO_RUNLOCK(&V_udbinfo);
 935                 error = SYSCTL_OUT(req, &xig, sizeof xig);
 936         }
 937         free(inp_list, M_TEMP);
 938         return (error);
 939 }
 940
 941 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
 942     CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
 943     udp_pcblist, "S,xinpcb", "List of active UDP sockets");
 944
 945 #ifdef INET
 946 static int
 947 udp_getcred(SYSCTL_HANDLER_ARGS)
 948 {
 949         struct xucred xuc;
 950         struct sockaddr_in addrs[2];
 951         struct inpcb *inp;
 952         int error;
 953
 954         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 955         if (error)
 956                 return (error);
 957         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 958         if (error)
 959                 return (error);
 960         inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
 961             addrs[0].sin_addr, addrs[0].sin_port,
 962             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 963         if (inp != NULL) {
 964                 INP_RLOCK_ASSERT(inp);
 965                 if (inp->inp_socket == NULL)
 966                         error = ENOENT;
 967                 if (error == 0)
 968                         error = cr_canseeinpcb(req->td->td_ucred, inp);
 969                 if (error == 0)
 970                         cru2x(inp->inp_cred, &xuc);
 971                 INP_RUNLOCK(inp);
 972         } else
 973                 error = ENOENT;
 974         if (error == 0)
 975                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 976         return (error);
 977 }
 978
 979 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
 980     CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
 981     udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
 982 #endif /* INET */
 983
 984 int
 985 udp_ctloutput(struct socket *so, struct sockopt *sopt)
 986 {
 987         struct inpcb *inp;
 988         struct udpcb *up;
 989         int isudplite, error, optval;
 990
 991         error = 0;
 992         isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
 993         inp = sotoinpcb(so);
 994         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 995         INP_WLOCK(inp);
 996         if (sopt->sopt_level != so->so_proto->pr_protocol) {
 997 #ifdef INET6
 998                 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
 999                         INP_WUNLOCK(inp);
1000                         error = ip6_ctloutput(so, sopt);
1001                 }
1002 #endif
1003 #if defined(INET) && defined(INET6)
1004                 else
1005 #endif
1006 #ifdef INET
1007                 {
1008                         INP_WUNLOCK(inp);
1009                         error = ip_ctloutput(so, sopt);
1010                 }
1011 #endif
1012                 return (error);
1013         }
1014
1015         switch (sopt->sopt_dir) {
1016         case SOPT_SET:
1017                 switch (sopt->sopt_name) {
1018 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1019 #ifdef INET
1020                 case UDP_ENCAP:
1021                         if (!IPSEC_ENABLED(ipv4)) {
1022                                 INP_WUNLOCK(inp);
1023                                 return (ENOPROTOOPT);
1024                         }
1025                         error = UDPENCAP_PCBCTL(inp, sopt);
1026                         break;
1027 #endif /* INET */
1028 #endif /* IPSEC */
1029                 case UDPLITE_SEND_CSCOV:
1030                 case UDPLITE_RECV_CSCOV:
1031                         if (!isudplite) {
1032                                 INP_WUNLOCK(inp);
1033                                 error = ENOPROTOOPT;
1034                                 break;
1035                         }
1036                         INP_WUNLOCK(inp);
1037                         error = sooptcopyin(sopt, &optval, sizeof(optval),
1038                             sizeof(optval));
1039                         if (error != 0)
1040                                 break;
1041                         inp = sotoinpcb(so);
1042                         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1043                         INP_WLOCK(inp);
1044                         up = intoudpcb(inp);
1045                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1046                         if ((optval != 0 && optval < 8) || (optval > 65535)) {
1047                                 INP_WUNLOCK(inp);
1048                                 error = EINVAL;
1049                                 break;
1050                         }
1051                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1052                                 up->u_txcslen = optval;
1053                         else
1054                                 up->u_rxcslen = optval;
1055                         INP_WUNLOCK(inp);
1056                         break;
1057                 default:
1058                         INP_WUNLOCK(inp);
1059                         error = ENOPROTOOPT;
1060                         break;
1061                 }
1062                 break;
1063         case SOPT_GET:
1064                 switch (sopt->sopt_name) {
1065 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1066 #ifdef INET
1067                 case UDP_ENCAP:
1068                         if (!IPSEC_ENABLED(ipv4)) {
1069                                 INP_WUNLOCK(inp);
1070                                 return (ENOPROTOOPT);
1071                         }
1072                         error = UDPENCAP_PCBCTL(inp, sopt);
1073                         break;
1074 #endif /* INET */
1075 #endif /* IPSEC */
1076                 case UDPLITE_SEND_CSCOV:
1077                 case UDPLITE_RECV_CSCOV:
1078                         if (!isudplite) {
1079                                 INP_WUNLOCK(inp);
1080                                 error = ENOPROTOOPT;
1081                                 break;
1082                         }
1083                         up = intoudpcb(inp);
1084                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1085                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1086                                 optval = up->u_txcslen;
1087                         else
1088                                 optval = up->u_rxcslen;
1089                         INP_WUNLOCK(inp);
1090                         error = sooptcopyout(sopt, &optval, sizeof(optval));
1091                         break;
1092                 default:
1093                         INP_WUNLOCK(inp);
1094                         error = ENOPROTOOPT;
1095                         break;
1096                 }
1097                 break;
1098         }
1099         return (error);
1100 }
1101
1102 #ifdef INET
1103 #define UH_WLOCKED      2
1104 #define UH_RLOCKED      1
1105 #define UH_UNLOCKED     0
1106 static int
1107 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
1108     struct mbuf *control, struct thread *td)
1109 {
1110         struct udpiphdr *ui;
1111         int len = m->m_pkthdr.len;
1112         struct in_addr faddr, laddr;
1113         struct cmsghdr *cm;
1114         struct inpcbinfo *pcbinfo;
1115         struct sockaddr_in *sin, src;
1116         int cscov_partial = 0;
1117         int error = 0;
1118         int ipflags;
1119         u_short fport, lport;
1120         int unlock_udbinfo, unlock_inp;
1121         u_char tos;
1122         uint8_t pr;
1123         uint16_t cscov = 0;
1124         uint32_t flowid = 0;
1125         uint8_t flowtype = M_HASHTYPE_NONE;
1126
1127         /*
1128          * udp_output() may need to temporarily bind or connect the current
1129          * inpcb.  As such, we don't know up front whether we will need the
1130          * pcbinfo lock or not.  Do any work to decide what is needed up
1131          * front before acquiring any locks.
1132          */
1133         if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1134                 if (control)
1135                         m_freem(control);
1136                 m_freem(m);
1137                 return (EMSGSIZE);
1138         }
1139
1140         src.sin_family = 0;
1141         sin = (struct sockaddr_in *)addr;
1142         if (sin == NULL ||
1143             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1144                 INP_WLOCK(inp);
1145                 unlock_inp = UH_WLOCKED;
1146         } else {
1147                 INP_RLOCK(inp);
1148                 unlock_inp = UH_RLOCKED;
1149         }
1150         tos = inp->inp_ip_tos;
1151         if (control != NULL) {
1152                 /*
1153                  * XXX: Currently, we assume all the optional information is
1154                  * stored in a single mbuf.
1155                  */
1156                 if (control->m_next) {
1157                         if (unlock_inp == UH_WLOCKED)
1158                                 INP_WUNLOCK(inp);
1159                         else
1160                                 INP_RUNLOCK(inp);
1161                         m_freem(control);
1162                         m_freem(m);
1163                         return (EINVAL);
1164                 }
1165                 for (; control->m_len > 0;
1166                     control->m_data += CMSG_ALIGN(cm->cmsg_len),
1167                     control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1168                         cm = mtod(control, struct cmsghdr *);
1169                         if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1170                             || cm->cmsg_len > control->m_len) {
1171                                 error = EINVAL;
1172                                 break;
1173                         }
1174                         if (cm->cmsg_level != IPPROTO_IP)
1175                                 continue;
1176
1177                         switch (cm->cmsg_type) {
1178                         case IP_SENDSRCADDR:
1179                                 if (cm->cmsg_len !=
1180                                     CMSG_LEN(sizeof(struct in_addr))) {
1181                                         error = EINVAL;
1182                                         break;
1183                                 }
1184                                 bzero(&src, sizeof(src));
1185                                 src.sin_family = AF_INET;
1186                                 src.sin_len = sizeof(src);
1187                                 src.sin_port = inp->inp_lport;
1188                                 src.sin_addr =
1189                                     *(struct in_addr *)CMSG_DATA(cm);
1190                                 break;
1191
1192                         case IP_TOS:
1193                                 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1194                                         error = EINVAL;
1195                                         break;
1196                                 }
1197                                 tos = *(u_char *)CMSG_DATA(cm);
1198                                 break;
1199
1200                         case IP_FLOWID:
1201                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1202                                         error = EINVAL;
1203                                         break;
1204                                 }
1205                                 flowid = *(uint32_t *) CMSG_DATA(cm);
1206                                 break;
1207
1208                         case IP_FLOWTYPE:
1209                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1210                                         error = EINVAL;
1211                                         break;
1212                                 }
1213                                 flowtype = *(uint32_t *) CMSG_DATA(cm);
1214                                 break;
1215
1216 #ifdef  RSS
1217                         case IP_RSSBUCKETID:
1218                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1219                                         error = EINVAL;
1220                                         break;
1221                                 }
1222                                 /* This is just a placeholder for now */
1223                                 break;
1224 #endif  /* RSS */
1225                         default:
1226                                 error = ENOPROTOOPT;
1227                                 break;
1228                         }
1229                         if (error)
1230                                 break;
1231                 }
1232                 m_freem(control);
1233         }
1234         if (error) {
1235                 if (unlock_inp == UH_WLOCKED)
1236                         INP_WUNLOCK(inp);
1237                 else
1238                         INP_RUNLOCK(inp);
1239                 m_freem(m);
1240                 return (error);
1241         }
1242
1243         /*
1244          * Depending on whether or not the application has bound or connected
1245          * the socket, we may have to do varying levels of work.  The optimal
1246          * case is for a connected UDP socket, as a global lock isn't
1247          * required at all.
1248          *
1249          * In order to decide which we need, we require stability of the
1250          * inpcb binding, which we ensure by acquiring a read lock on the
1251          * inpcb.  This doesn't strictly follow the lock order, so we play
1252          * the trylock and retry game; note that we may end up with more
1253          * conservative locks than required the second time around, so later
1254          * assertions have to accept that.  Further analysis of the number of
1255          * misses under contention is required.
1256          *
1257          * XXXRW: Check that hash locking update here is correct.
1258          */
1259         pr = inp->inp_socket->so_proto->pr_protocol;
1260         pcbinfo = udp_get_inpcbinfo(pr);
1261         sin = (struct sockaddr_in *)addr;
1262         if (sin != NULL &&
1263             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1264                 INP_HASH_WLOCK(pcbinfo);
1265                 unlock_udbinfo = UH_WLOCKED;
1266         } else if ((sin != NULL && (
1267             (sin->sin_addr.s_addr == INADDR_ANY) ||
1268             (sin->sin_addr.s_addr == INADDR_BROADCAST) ||
1269             (inp->inp_laddr.s_addr == INADDR_ANY) ||
1270             (inp->inp_lport == 0))) ||
1271             (src.sin_family == AF_INET)) {
1272                 INP_HASH_RLOCK(pcbinfo);
1273                 unlock_udbinfo = UH_RLOCKED;
1274         } else
1275                 unlock_udbinfo = UH_UNLOCKED;
1276
1277         /*
1278          * If the IP_SENDSRCADDR control message was specified, override the
1279          * source address for this datagram.  Its use is invalidated if the
1280          * address thus specified is incomplete or clobbers other inpcbs.
1281          */
1282         laddr = inp->inp_laddr;
1283         lport = inp->inp_lport;
1284         if (src.sin_family == AF_INET) {
1285                 INP_HASH_LOCK_ASSERT(pcbinfo);
1286                 if ((lport == 0) ||
1287                     (laddr.s_addr == INADDR_ANY &&
1288                      src.sin_addr.s_addr == INADDR_ANY)) {
1289                         error = EINVAL;
1290                         goto release;
1291                 }
1292                 error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
1293                     &laddr.s_addr, &lport, td->td_ucred);
1294                 if (error)
1295                         goto release;
1296         }
1297
1298         /*
1299          * If a UDP socket has been connected, then a local address/port will
1300          * have been selected and bound.
1301          *
1302          * If a UDP socket has not been connected to, then an explicit
1303          * destination address must be used, in which case a local
1304          * address/port may not have been selected and bound.
1305          */
1306         if (sin != NULL) {
1307                 INP_LOCK_ASSERT(inp);
1308                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1309                         error = EISCONN;
1310                         goto release;
1311                 }
1312
1313                 /*
1314                  * Jail may rewrite the destination address, so let it do
1315                  * that before we use it.
1316                  */
1317                 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1318                 if (error)
1319                         goto release;
1320
1321                 /*
1322                  * If a local address or port hasn't yet been selected, or if
1323                  * the destination address needs to be rewritten due to using
1324                  * a special INADDR_ constant, invoke in_pcbconnect_setup()
1325                  * to do the heavy lifting.  Once a port is selected, we
1326                  * commit the binding back to the socket; we also commit the
1327                  * binding of the address if in jail.
1328                  *
1329                  * If we already have a valid binding and we're not
1330                  * requesting a destination address rewrite, use a fast path.
1331                  */
1332                 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1333                     inp->inp_lport == 0 ||
1334                     sin->sin_addr.s_addr == INADDR_ANY ||
1335                     sin->sin_addr.s_addr == INADDR_BROADCAST) {
1336                         INP_HASH_LOCK_ASSERT(pcbinfo);
1337                         error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
1338                             &lport, &faddr.s_addr, &fport, NULL,
1339                             td->td_ucred);
1340                         if (error)
1341                                 goto release;
1342
1343                         /*
1344                          * XXXRW: Why not commit the port if the address is
1345                          * !INADDR_ANY?
1346                          */
1347                         /* Commit the local port if newly assigned. */
1348                         if (inp->inp_laddr.s_addr == INADDR_ANY &&
1349                             inp->inp_lport == 0) {
1350                                 INP_WLOCK_ASSERT(inp);
1351                                 INP_HASH_WLOCK_ASSERT(pcbinfo);
1352                                 /*
1353                                  * Remember addr if jailed, to prevent
1354                                  * rebinding.
1355                                  */
1356                                 if (prison_flag(td->td_ucred, PR_IP4))
1357                                         inp->inp_laddr = laddr;
1358                                 inp->inp_lport = lport;
1359                                 if (in_pcbinshash(inp) != 0) {
1360                                         inp->inp_lport = 0;
1361                                         error = EAGAIN;
1362                                         goto release;
1363                                 }
1364                                 inp->inp_flags |= INP_ANONPORT;
1365                         }
1366                 } else {
1367                         faddr = sin->sin_addr;
1368                         fport = sin->sin_port;
1369                 }
1370         } else {
1371                 INP_LOCK_ASSERT(inp);
1372                 faddr = inp->inp_faddr;
1373                 fport = inp->inp_fport;
1374                 if (faddr.s_addr == INADDR_ANY) {
1375                         error = ENOTCONN;
1376                         goto release;
1377                 }
1378         }
1379
1380         /*
1381          * Calculate data length and get a mbuf for UDP, IP, and possible
1382          * link-layer headers.  Immediate slide the data pointer back forward
1383          * since we won't use that space at this layer.
1384          */
1385         M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1386         if (m == NULL) {
1387                 error = ENOBUFS;
1388                 goto release;
1389         }
1390         m->m_data += max_linkhdr;
1391         m->m_len -= max_linkhdr;
1392         m->m_pkthdr.len -= max_linkhdr;
1393
1394         /*
1395          * Fill in mbuf with extended UDP header and addresses and length put
1396          * into network format.
1397          */
1398         ui = mtod(m, struct udpiphdr *);
1399         bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1400         ui->ui_pr = pr;
1401         ui->ui_src = laddr;
1402         ui->ui_dst = faddr;
1403         ui->ui_sport = lport;
1404         ui->ui_dport = fport;
1405         ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1406         if (pr == IPPROTO_UDPLITE) {
1407                 struct udpcb *up;
1408                 uint16_t plen;
1409
1410                 up = intoudpcb(inp);
1411                 cscov = up->u_txcslen;
1412                 plen = (u_short)len + sizeof(struct udphdr);
1413                 if (cscov >= plen)
1414                         cscov = 0;
1415                 ui->ui_len = htons(plen);
1416                 ui->ui_ulen = htons(cscov);
1417                 /*
1418                  * For UDP-Lite, checksum coverage length of zero means
1419                  * the entire UDPLite packet is covered by the checksum.
1420                  */
1421                 cscov_partial = (cscov == 0) ? 0 : 1;
1422         } else
1423                 ui->ui_v = IPVERSION << 4;
1424
1425         /*
1426          * Set the Don't Fragment bit in the IP header.
1427          */
1428         if (inp->inp_flags & INP_DONTFRAG) {
1429                 struct ip *ip;
1430
1431                 ip = (struct ip *)&ui->ui_i;
1432                 ip->ip_off |= htons(IP_DF);
1433         }
1434
1435         ipflags = 0;
1436         if (inp->inp_socket->so_options & SO_DONTROUTE)
1437                 ipflags |= IP_ROUTETOIF;
1438         if (inp->inp_socket->so_options & SO_BROADCAST)
1439                 ipflags |= IP_ALLOWBROADCAST;
1440         if (inp->inp_flags & INP_ONESBCAST)
1441                 ipflags |= IP_SENDONES;
1442
1443 #ifdef MAC
1444         mac_inpcb_create_mbuf(inp, m);
1445 #endif
1446
1447         /*
1448          * Set up checksum and output datagram.
1449          */
1450         ui->ui_sum = 0;
1451         if (pr == IPPROTO_UDPLITE) {
1452                 if (inp->inp_flags & INP_ONESBCAST)
1453                         faddr.s_addr = INADDR_BROADCAST;
1454                 if (cscov_partial) {
1455                         if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1456                                 ui->ui_sum = 0xffff;
1457                 } else {
1458                         if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1459                                 ui->ui_sum = 0xffff;
1460                 }
1461         } else if (V_udp_cksum) {
1462                 if (inp->inp_flags & INP_ONESBCAST)
1463                         faddr.s_addr = INADDR_BROADCAST;
1464                 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1465                     htons((u_short)len + sizeof(struct udphdr) + pr));
1466                 m->m_pkthdr.csum_flags = CSUM_UDP;
1467                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1468         }
1469         ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1470         ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1471         ((struct ip *)ui)->ip_tos = tos;                /* XXX */
1472         UDPSTAT_INC(udps_opackets);
1473
1474         /*
1475          * Setup flowid / RSS information for outbound socket.
1476          *
1477          * Once the UDP code decides to set a flowid some other way,
1478          * this allows the flowid to be overridden by userland.
1479          */
1480         if (flowtype != M_HASHTYPE_NONE) {
1481                 m->m_pkthdr.flowid = flowid;
1482                 M_HASHTYPE_SET(m, flowtype);
1483 #ifdef  RSS
1484         } else {
1485                 uint32_t hash_val, hash_type;
1486                 /*
1487                  * Calculate an appropriate RSS hash for UDP and
1488                  * UDP Lite.
1489                  *
1490                  * The called function will take care of figuring out
1491                  * whether a 2-tuple or 4-tuple hash is required based
1492                  * on the currently configured scheme.
1493                  *
1494                  * Later later on connected socket values should be
1495                  * cached in the inpcb and reused, rather than constantly
1496                  * re-calculating it.
1497                  *
1498                  * UDP Lite is a different protocol number and will
1499                  * likely end up being hashed as a 2-tuple until
1500                  * RSS / NICs grow UDP Lite protocol awareness.
1501                  */
1502                 if (rss_proto_software_hash_v4(faddr, laddr, fport, lport,
1503                     pr, &hash_val, &hash_type) == 0) {
1504                         m->m_pkthdr.flowid = hash_val;
1505                         M_HASHTYPE_SET(m, hash_type);
1506                 }
1507 #endif
1508         }
1509
1510 #ifdef  RSS
1511         /*
1512          * Don't override with the inp cached flowid value.
1513          *
1514          * Depending upon the kind of send being done, the inp
1515          * flowid/flowtype values may actually not be appropriate
1516          * for this particular socket send.
1517          *
1518          * We should either leave the flowid at zero (which is what is
1519          * currently done) or set it to some software generated
1520          * hash value based on the packet contents.
1521          */
1522         ipflags |= IP_NODEFAULTFLOWID;
1523 #endif  /* RSS */
1524
1525         if (unlock_udbinfo == UH_WLOCKED)
1526                 INP_HASH_WUNLOCK(pcbinfo);
1527         else if (unlock_udbinfo == UH_RLOCKED)
1528                 INP_HASH_RUNLOCK(pcbinfo);
1529         UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1530         error = ip_output(m, inp->inp_options,
1531             (unlock_inp == UH_WLOCKED ? &inp->inp_route : NULL), ipflags,
1532             inp->inp_moptions, inp);
1533         if (unlock_inp == UH_WLOCKED)
1534                 INP_WUNLOCK(inp);
1535         else
1536                 INP_RUNLOCK(inp);
1537         return (error);
1538
1539 release:
1540         if (unlock_udbinfo == UH_WLOCKED) {
1541                 KASSERT(unlock_inp == UH_WLOCKED,
1542                     ("%s: excl udbinfo lock, shared inp lock", __func__));
1543                 INP_HASH_WUNLOCK(pcbinfo);
1544                 INP_WUNLOCK(inp);
1545         } else if (unlock_udbinfo == UH_RLOCKED) {
1546                 KASSERT(unlock_inp == UH_RLOCKED,
1547                     ("%s: shared udbinfo lock, excl inp lock", __func__));
1548                 INP_HASH_RUNLOCK(pcbinfo);
1549                 INP_RUNLOCK(inp);
1550         } else if (unlock_inp == UH_WLOCKED)
1551                 INP_WUNLOCK(inp);
1552         else
1553                 INP_RUNLOCK(inp);
1554         m_freem(m);
1555         return (error);
1556 }
1557
1558 static void
1559 udp_abort(struct socket *so)
1560 {
1561         struct inpcb *inp;
1562         struct inpcbinfo *pcbinfo;
1563
1564         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1565         inp = sotoinpcb(so);
1566         KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1567         INP_WLOCK(inp);
1568         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1569                 INP_HASH_WLOCK(pcbinfo);
1570                 in_pcbdisconnect(inp);
1571                 inp->inp_laddr.s_addr = INADDR_ANY;
1572                 INP_HASH_WUNLOCK(pcbinfo);
1573                 soisdisconnected(so);
1574         }
1575         INP_WUNLOCK(inp);
1576 }
1577
1578 static int
1579 udp_attach(struct socket *so, int proto, struct thread *td)
1580 {
1581         struct inpcb *inp;
1582         struct inpcbinfo *pcbinfo;
1583         int error;
1584
1585         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1586         inp = sotoinpcb(so);
1587         KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1588         error = soreserve(so, udp_sendspace, udp_recvspace);
1589         if (error)
1590                 return (error);
1591         INP_INFO_WLOCK(pcbinfo);
1592         error = in_pcballoc(so, pcbinfo);
1593         if (error) {
1594                 INP_INFO_WUNLOCK(pcbinfo);
1595                 return (error);
1596         }
1597
1598         inp = sotoinpcb(so);
1599         inp->inp_vflag |= INP_IPV4;
1600         inp->inp_ip_ttl = V_ip_defttl;
1601
1602         error = udp_newudpcb(inp);
1603         if (error) {
1604                 in_pcbdetach(inp);
1605                 in_pcbfree(inp);
1606                 INP_INFO_WUNLOCK(pcbinfo);
1607                 return (error);
1608         }
1609
1610         INP_WUNLOCK(inp);
1611         INP_INFO_WUNLOCK(pcbinfo);
1612         return (0);
1613 }
1614 #endif /* INET */
1615
1616 int
1617 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1618 {
1619         struct inpcb *inp;
1620         struct udpcb *up;
1621
1622         KASSERT(so->so_type == SOCK_DGRAM,
1623             ("udp_set_kernel_tunneling: !dgram"));
1624         inp = sotoinpcb(so);
1625         KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1626         INP_WLOCK(inp);
1627         up = intoudpcb(inp);
1628         if ((up->u_tun_func != NULL) ||
1629             (up->u_icmp_func != NULL)) {
1630                 INP_WUNLOCK(inp);
1631                 return (EBUSY);
1632         }
1633         up->u_tun_func = f;
1634         up->u_icmp_func = i;
1635         up->u_tun_ctx = ctx;
1636         INP_WUNLOCK(inp);
1637         return (0);
1638 }
1639
1640 #ifdef INET
1641 static int
1642 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1643 {
1644         struct inpcb *inp;
1645         struct inpcbinfo *pcbinfo;
1646         int error;
1647
1648         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1649         inp = sotoinpcb(so);
1650         KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1651         INP_WLOCK(inp);
1652         INP_HASH_WLOCK(pcbinfo);
1653         error = in_pcbbind(inp, nam, td->td_ucred);
1654         INP_HASH_WUNLOCK(pcbinfo);
1655         INP_WUNLOCK(inp);
1656         return (error);
1657 }
1658
1659 static void
1660 udp_close(struct socket *so)
1661 {
1662         struct inpcb *inp;
1663         struct inpcbinfo *pcbinfo;
1664
1665         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1666         inp = sotoinpcb(so);
1667         KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1668         INP_WLOCK(inp);
1669         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1670                 INP_HASH_WLOCK(pcbinfo);
1671                 in_pcbdisconnect(inp);
1672                 inp->inp_laddr.s_addr = INADDR_ANY;
1673                 INP_HASH_WUNLOCK(pcbinfo);
1674                 soisdisconnected(so);
1675         }
1676         INP_WUNLOCK(inp);
1677 }
1678
1679 static int
1680 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1681 {
1682         struct inpcb *inp;
1683         struct inpcbinfo *pcbinfo;
1684         struct sockaddr_in *sin;
1685         int error;
1686
1687         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1688         inp = sotoinpcb(so);
1689         KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1690         INP_WLOCK(inp);
1691         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1692                 INP_WUNLOCK(inp);
1693                 return (EISCONN);
1694         }
1695         sin = (struct sockaddr_in *)nam;
1696         error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1697         if (error != 0) {
1698                 INP_WUNLOCK(inp);
1699                 return (error);
1700         }
1701         INP_HASH_WLOCK(pcbinfo);
1702         error = in_pcbconnect(inp, nam, td->td_ucred);
1703         INP_HASH_WUNLOCK(pcbinfo);
1704         if (error == 0)
1705                 soisconnected(so);
1706         INP_WUNLOCK(inp);
1707         return (error);
1708 }
1709
1710 static void
1711 udp_detach(struct socket *so)
1712 {
1713         struct inpcb *inp;
1714         struct inpcbinfo *pcbinfo;
1715         struct udpcb *up;
1716
1717         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1718         inp = sotoinpcb(so);
1719         KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1720         KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1721             ("udp_detach: not disconnected"));
1722         INP_INFO_WLOCK(pcbinfo);
1723         INP_WLOCK(inp);
1724         up = intoudpcb(inp);
1725         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1726         inp->inp_ppcb = NULL;
1727         in_pcbdetach(inp);
1728         in_pcbfree(inp);
1729         INP_INFO_WUNLOCK(pcbinfo);
1730         udp_discardcb(up);
1731 }
1732
1733 static int
1734 udp_disconnect(struct socket *so)
1735 {
1736         struct inpcb *inp;
1737         struct inpcbinfo *pcbinfo;
1738
1739         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1740         inp = sotoinpcb(so);
1741         KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1742         INP_WLOCK(inp);
1743         if (inp->inp_faddr.s_addr == INADDR_ANY) {
1744                 INP_WUNLOCK(inp);
1745                 return (ENOTCONN);
1746         }
1747         INP_HASH_WLOCK(pcbinfo);
1748         in_pcbdisconnect(inp);
1749         inp->inp_laddr.s_addr = INADDR_ANY;
1750         INP_HASH_WUNLOCK(pcbinfo);
1751         SOCK_LOCK(so);
1752         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1753         SOCK_UNLOCK(so);
1754         INP_WUNLOCK(inp);
1755         return (0);
1756 }
1757
1758 static int
1759 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1760     struct mbuf *control, struct thread *td)
1761 {
1762         struct inpcb *inp;
1763
1764         inp = sotoinpcb(so);
1765         KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1766         return (udp_output(inp, m, addr, control, td));
1767 }
1768 #endif /* INET */
1769
1770 int
1771 udp_shutdown(struct socket *so)
1772 {
1773         struct inpcb *inp;
1774
1775         inp = sotoinpcb(so);
1776         KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1777         INP_WLOCK(inp);
1778         socantsendmore(so);
1779         INP_WUNLOCK(inp);
1780         return (0);
1781 }
1782
1783 #ifdef INET
1784 struct pr_usrreqs udp_usrreqs = {
1785         .pru_abort =            udp_abort,
1786         .pru_attach =           udp_attach,
1787         .pru_bind =             udp_bind,
1788         .pru_connect =          udp_connect,
1789         .pru_control =          in_control,
1790         .pru_detach =           udp_detach,
1791         .pru_disconnect =       udp_disconnect,
1792         .pru_peeraddr =         in_getpeeraddr,
1793         .pru_send =             udp_send,
1794         .pru_soreceive =        soreceive_dgram,
1795         .pru_sosend =           sosend_dgram,
1796         .pru_shutdown =         udp_shutdown,
1797         .pru_sockaddr =         in_getsockaddr,
1798         .pru_sosetlabel =       in_pcbsosetlabel,
1799         .pru_close =            udp_close,
1800 };
1801 #endif /* INET */