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  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 4. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      @(#)udp_usrreq.c        8.6 (Berkeley) 5/23/95
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include "opt_ipfw.h"
  38 #include "opt_inet6.h"
  39 #include "opt_ipsec.h"
  40 #include "opt_mac.h"
  41
  42 #include <sys/param.h>
  43 #include <sys/domain.h>
  44 #include <sys/eventhandler.h>
  45 #include <sys/jail.h>
  46 #include <sys/kernel.h>
  47 #include <sys/lock.h>
  48 #include <sys/malloc.h>
  49 #include <sys/mbuf.h>
  50 #include <sys/priv.h>
  51 #include <sys/proc.h>
  52 #include <sys/protosw.h>
  53 #include <sys/signalvar.h>
  54 #include <sys/socket.h>
  55 #include <sys/socketvar.h>
  56 #include <sys/sx.h>
  57 #include <sys/sysctl.h>
  58 #include <sys/syslog.h>
  59 #include <sys/systm.h>
  60 #include <sys/vimage.h>
  61
  62 #include <vm/uma.h>
  63
  64 #include <net/if.h>
  65 #include <net/route.h>
  66
  67 #include <netinet/in.h>
  68 #include <netinet/in_pcb.h>
  69 #include <netinet/in_systm.h>
  70 #include <netinet/in_var.h>
  71 #include <netinet/ip.h>
  72 #ifdef INET6
  73 #include <netinet/ip6.h>
  74 #endif
  75 #include <netinet/ip_icmp.h>
  76 #include <netinet/icmp_var.h>
  77 #include <netinet/ip_var.h>
  78 #include <netinet/ip_options.h>
  79 #ifdef INET6
  80 #include <netinet6/ip6_var.h>
  81 #endif
  82 #include <netinet/udp.h>
  83 #include <netinet/udp_var.h>
  84
  85 #ifdef IPSEC
  86 #include <netipsec/ipsec.h>
  87 #endif
  88
  89 #include <machine/in_cksum.h>
  90
  91 #include <security/mac/mac_framework.h>
  92
  93 /*
  94  * UDP protocol implementation.
  95  * Per RFC 768, August, 1980.
  96  */
  97
  98 /*
  99  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
 100  * removes the only data integrity mechanism for packets and malformed
 101  * packets that would otherwise be discarded due to bad checksums, and may
 102  * cause problems (especially for NFS data blocks).
 103  */
 104 static int      udp_cksum = 1;
 105 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, &udp_cksum,
 106     0, "compute udp checksum");
 107
 108 int     udp_log_in_vain = 0;
 109 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW,
 110     &udp_log_in_vain, 0, "Log all incoming UDP packets");
 111
 112 int     udp_blackhole = 0;
 113 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW, &udp_blackhole, 0,
 114     "Do not send port unreachables for refused connects");
 115
 116 u_long  udp_sendspace = 9216;           /* really max datagram size */
 117                                         /* 40 1K datagrams */
 118 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
 119     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
 120
 121 u_long  udp_recvspace = 40 * (1024 +
 122 #ifdef INET6
 123                                       sizeof(struct sockaddr_in6)
 124 #else
 125                                       sizeof(struct sockaddr_in)
 126 #endif
 127                                       );
 128
 129 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
 130     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
 131
 132 struct inpcbhead        udb;            /* from udp_var.h */
 133 struct inpcbinfo        udbinfo;
 134
 135 #ifndef UDBHASHSIZE
 136 #define UDBHASHSIZE     128
 137 #endif
 138
 139 struct udpstat  udpstat;        /* from udp_var.h */
 140 SYSCTL_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW, &udpstat,
 141     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
 142
 143 static void     udp_detach(struct socket *so);
 144 static int      udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
 145                     struct mbuf *, struct thread *);
 146
 147 static void
 148 udp_zone_change(void *tag)
 149 {
 150
 151         uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
 152 }
 153
 154 static int
 155 udp_inpcb_init(void *mem, int size, int flags)
 156 {
 157         struct inpcb *inp;
 158
 159         inp = mem;
 160         INP_LOCK_INIT(inp, "inp", "udpinp");
 161         return (0);
 162 }
 163
 164 void
 165 udp_init(void)
 166 {
 167
 168         INP_INFO_LOCK_INIT(&V_udbinfo, "udp");
 169         LIST_INIT(&V_udb);
 170         V_udbinfo.ipi_listhead = &udb;
 171         V_udbinfo.ipi_hashbase = hashinit(UDBHASHSIZE, M_PCB,
 172             &V_udbinfo.ipi_hashmask);
 173         V_udbinfo.ipi_porthashbase = hashinit(UDBHASHSIZE, M_PCB,
 174             &V_udbinfo.ipi_porthashmask);
 175         V_udbinfo.ipi_zone = uma_zcreate("udpcb", sizeof(struct inpcb), NULL,
 176             NULL, udp_inpcb_init, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
 177         uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
 178         EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL,
 179             EVENTHANDLER_PRI_ANY);
 180 }
 181
 182 /*
 183  * Subroutine of udp_input(), which appends the provided mbuf chain to the
 184  * passed pcb/socket.  The caller must provide a sockaddr_in via udp_in that
 185  * contains the source address.  If the socket ends up being an IPv6 socket,
 186  * udp_append() will convert to a sockaddr_in6 before passing the address
 187  * into the socket code.
 188  */
 189 static void
 190 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
 191     struct sockaddr_in *udp_in)
 192 {
 193         struct sockaddr *append_sa;
 194         struct socket *so;
 195         struct mbuf *opts = 0;
 196 #ifdef INET6
 197         struct sockaddr_in6 udp_in6;
 198 #endif
 199
 200         INP_RLOCK_ASSERT(inp);
 201
 202 #ifdef IPSEC
 203         /* Check AH/ESP integrity. */
 204         if (ipsec4_in_reject(n, inp)) {
 205                 m_freem(n);
 206                 V_ipsec4stat.in_polvio++;
 207                 return;
 208         }
 209 #endif /* IPSEC */
 210 #ifdef MAC
 211         if (mac_inpcb_check_deliver(inp, n) != 0) {
 212                 m_freem(n);
 213                 return;
 214         }
 215 #endif
 216         if (inp->inp_flags & INP_CONTROLOPTS ||
 217             inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
 218 #ifdef INET6
 219                 if (inp->inp_vflag & INP_IPV6)
 220                         (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
 221                 else
 222 #endif
 223                         ip_savecontrol(inp, &opts, ip, n);
 224         }
 225 #ifdef INET6
 226         if (inp->inp_vflag & INP_IPV6) {
 227                 bzero(&udp_in6, sizeof(udp_in6));
 228                 udp_in6.sin6_len = sizeof(udp_in6);
 229                 udp_in6.sin6_family = AF_INET6;
 230                 in6_sin_2_v4mapsin6(udp_in, &udp_in6);
 231                 append_sa = (struct sockaddr *)&udp_in6;
 232         } else
 233 #endif
 234                 append_sa = (struct sockaddr *)udp_in;
 235         m_adj(n, off);
 236
 237         so = inp->inp_socket;
 238         SOCKBUF_LOCK(&so->so_rcv);
 239         if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
 240                 SOCKBUF_UNLOCK(&so->so_rcv);
 241                 m_freem(n);
 242                 if (opts)
 243                         m_freem(opts);
 244                 V_udpstat.udps_fullsock++;
 245         } else
 246                 sorwakeup_locked(so);
 247 }
 248
 249 void
 250 udp_input(struct mbuf *m, int off)
 251 {
 252         int iphlen = off;
 253         struct ip *ip;
 254         struct udphdr *uh;
 255         struct ifnet *ifp;
 256         struct inpcb *inp;
 257         int len;
 258         struct ip save_ip;
 259         struct sockaddr_in udp_in;
 260 #ifdef IPFIREWALL_FORWARD
 261         struct m_tag *fwd_tag;
 262 #endif
 263
 264         ifp = m->m_pkthdr.rcvif;
 265         V_udpstat.udps_ipackets++;
 266
 267         /*
 268          * Strip IP options, if any; should skip this, make available to
 269          * user, and use on returned packets, but we don't yet have a way to
 270          * check the checksum with options still present.
 271          */
 272         if (iphlen > sizeof (struct ip)) {
 273                 ip_stripoptions(m, (struct mbuf *)0);
 274                 iphlen = sizeof(struct ip);
 275         }
 276
 277         /*
 278          * Get IP and UDP header together in first mbuf.
 279          */
 280         ip = mtod(m, struct ip *);
 281         if (m->m_len < iphlen + sizeof(struct udphdr)) {
 282                 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) {
 283                         V_udpstat.udps_hdrops++;
 284                         return;
 285                 }
 286                 ip = mtod(m, struct ip *);
 287         }
 288         uh = (struct udphdr *)((caddr_t)ip + iphlen);
 289
 290         /*
 291          * Destination port of 0 is illegal, based on RFC768.
 292          */
 293         if (uh->uh_dport == 0)
 294                 goto badunlocked;
 295
 296         /*
 297          * Construct sockaddr format source address.  Stuff source address
 298          * and datagram in user buffer.
 299          */
 300         bzero(&udp_in, sizeof(udp_in));
 301         udp_in.sin_len = sizeof(udp_in);
 302         udp_in.sin_family = AF_INET;
 303         udp_in.sin_port = uh->uh_sport;
 304         udp_in.sin_addr = ip->ip_src;
 305
 306         /*
 307          * Make mbuf data length reflect UDP length.  If not enough data to
 308          * reflect UDP length, drop.
 309          */
 310         len = ntohs((u_short)uh->uh_ulen);
 311         if (ip->ip_len != len) {
 312                 if (len > ip->ip_len || len < sizeof(struct udphdr)) {
 313                         V_udpstat.udps_badlen++;
 314                         goto badunlocked;
 315                 }
 316                 m_adj(m, len - ip->ip_len);
 317                 /* ip->ip_len = len; */
 318         }
 319
 320         /*
 321          * Save a copy of the IP header in case we want restore it for
 322          * sending an ICMP error message in response.
 323          */
 324         if (!V_udp_blackhole)
 325                 save_ip = *ip;
 326         else
 327                 memset(&save_ip, 0, sizeof(save_ip));
 328
 329         /*
 330          * Checksum extended UDP header and data.
 331          */
 332         if (uh->uh_sum) {
 333                 u_short uh_sum;
 334
 335                 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
 336                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 337                                 uh_sum = m->m_pkthdr.csum_data;
 338                         else
 339                                 uh_sum = in_pseudo(ip->ip_src.s_addr,
 340                                     ip->ip_dst.s_addr, htonl((u_short)len +
 341                                     m->m_pkthdr.csum_data + IPPROTO_UDP));
 342                         uh_sum ^= 0xffff;
 343                 } else {
 344                         char b[9];
 345
 346                         bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
 347                         bzero(((struct ipovly *)ip)->ih_x1, 9);
 348                         ((struct ipovly *)ip)->ih_len = uh->uh_ulen;
 349                         uh_sum = in_cksum(m, len + sizeof (struct ip));
 350                         bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
 351                 }
 352                 if (uh_sum) {
 353                         V_udpstat.udps_badsum++;
 354                         m_freem(m);
 355                         return;
 356                 }
 357         } else
 358                 V_udpstat.udps_nosum++;
 359
 360 #ifdef IPFIREWALL_FORWARD
 361         /*
 362          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 363          */
 364         fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
 365         if (fwd_tag != NULL) {
 366                 struct sockaddr_in *next_hop;
 367
 368                 /*
 369                  * Do the hack.
 370                  */
 371                 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
 372                 ip->ip_dst = next_hop->sin_addr;
 373                 uh->uh_dport = ntohs(next_hop->sin_port);
 374
 375                 /*
 376                  * Remove the tag from the packet.  We don't need it anymore.
 377                  */
 378                 m_tag_delete(m, fwd_tag);
 379         }
 380 #endif
 381
 382         INP_INFO_RLOCK(&V_udbinfo);
 383         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
 384             in_broadcast(ip->ip_dst, ifp)) {
 385                 struct inpcb *last;
 386                 struct ip_moptions *imo;
 387
 388                 last = NULL;
 389                 LIST_FOREACH(inp, &V_udb, inp_list) {
 390                         if (inp->inp_lport != uh->uh_dport)
 391                                 continue;
 392 #ifdef INET6
 393                         if ((inp->inp_vflag & INP_IPV4) == 0)
 394                                 continue;
 395 #endif
 396                         if (inp->inp_laddr.s_addr != INADDR_ANY &&
 397                             inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
 398                                 continue;
 399                         if (inp->inp_faddr.s_addr != INADDR_ANY &&
 400                             inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 401                                 continue;
 402                         /*
 403                          * XXX: Do not check source port of incoming datagram
 404                          * unless inp_connect() has been called to bind the
 405                          * fport part of the 4-tuple; the source could be
 406                          * trying to talk to us with an ephemeral port.
 407                          */
 408                         if (inp->inp_fport != 0 &&
 409                             inp->inp_fport != uh->uh_sport)
 410                                 continue;
 411
 412                         INP_RLOCK(inp);
 413
 414                         /*
 415                          * Handle socket delivery policy for any-source
 416                          * and source-specific multicast. [RFC3678]
 417                          */
 418                         imo = inp->inp_moptions;
 419                         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
 420                             imo != NULL) {
 421                                 struct sockaddr_in       sin;
 422                                 struct in_msource       *ims;
 423                                 int                      blocked, mode;
 424                                 size_t                   idx;
 425
 426                                 bzero(&sin, sizeof(struct sockaddr_in));
 427                                 sin.sin_len = sizeof(struct sockaddr_in);
 428                                 sin.sin_family = AF_INET;
 429                                 sin.sin_addr = ip->ip_dst;
 430
 431                                 blocked = 0;
 432                                 idx = imo_match_group(imo, ifp,
 433                                     (struct sockaddr *)&sin);
 434                                 if (idx == -1) {
 435                                         /*
 436                                          * No group membership for this socket.
 437                                          * Do not bump udps_noportbcast, as
 438                                          * this will happen further down.
 439                                          */
 440                                         blocked++;
 441                                 } else {
 442                                         /*
 443                                          * Check for a multicast source filter
 444                                          * entry on this socket for this group.
 445                                          * MCAST_EXCLUDE is the default
 446                                          * behaviour.  It means default accept;
 447                                          * entries, if present, denote sources
 448                                          * to be excluded from delivery.
 449                                          */
 450                                         ims = imo_match_source(imo, idx,
 451                                             (struct sockaddr *)&udp_in);
 452                                         mode = imo->imo_mfilters[idx].imf_fmode;
 453                                         if ((ims != NULL &&
 454                                              mode == MCAST_EXCLUDE) ||
 455                                             (ims == NULL &&
 456                                              mode == MCAST_INCLUDE)) {
 457 #ifdef DIAGNOSTIC
 458                                                 if (bootverbose) {
 459                                                         printf("%s: blocked by"
 460                                                             " source filter\n",
 461                                                             __func__);
 462                                                 }
 463 #endif
 464                                                 V_udpstat.udps_filtermcast++;
 465                                                 blocked++;
 466                                         }
 467                                 }
 468                                 if (blocked != 0) {
 469                                         INP_RUNLOCK(inp);
 470                                         continue;
 471                                 }
 472                         }
 473                         if (last != NULL) {
 474                                 struct mbuf *n;
 475
 476                                 n = m_copy(m, 0, M_COPYALL);
 477                                 if (n != NULL)
 478                                         udp_append(last, ip, n, iphlen +
 479                                             sizeof(struct udphdr), &udp_in);
 480                                 INP_RUNLOCK(last);
 481                         }
 482                         last = inp;
 483                         /*
 484                          * Don't look for additional matches if this one does
 485                          * not have either the SO_REUSEPORT or SO_REUSEADDR
 486                          * socket options set.  This heuristic avoids
 487                          * searching through all pcbs in the common case of a
 488                          * non-shared port.  It assumes that an application
 489                          * will never clear these options after setting them.
 490                          */
 491                         if ((last->inp_socket->so_options &
 492                             (SO_REUSEPORT|SO_REUSEADDR)) == 0)
 493                                 break;
 494                 }
 495
 496                 if (last == NULL) {
 497                         /*
 498                          * No matching pcb found; discard datagram.  (No need
 499                          * to send an ICMP Port Unreachable for a broadcast
 500                          * or multicast datgram.)
 501                          */
 502                         V_udpstat.udps_noportbcast++;
 503                         goto badheadlocked;
 504                 }
 505                 udp_append(last, ip, m, iphlen + sizeof(struct udphdr),
 506                     &udp_in);
 507                 INP_RUNLOCK(last);
 508                 INP_INFO_RUNLOCK(&V_udbinfo);
 509                 return;
 510         }
 511
 512         /*
 513          * Locate pcb for datagram.
 514          */
 515         inp = in_pcblookup_hash(&V_udbinfo, ip->ip_src, uh->uh_sport,
 516             ip->ip_dst, uh->uh_dport, 1, ifp);
 517         if (inp == NULL) {
 518                 if (udp_log_in_vain) {
 519                         char buf[4*sizeof "123"];
 520
 521                         strcpy(buf, inet_ntoa(ip->ip_dst));
 522                         log(LOG_INFO,
 523                             "Connection attempt to UDP %s:%d from %s:%d\n",
 524                             buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src),
 525                             ntohs(uh->uh_sport));
 526                 }
 527                 V_udpstat.udps_noport++;
 528                 if (m->m_flags & (M_BCAST | M_MCAST)) {
 529                         V_udpstat.udps_noportbcast++;
 530                         goto badheadlocked;
 531                 }
 532                 if (V_udp_blackhole)
 533                         goto badheadlocked;
 534                 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
 535                         goto badheadlocked;
 536                 *ip = save_ip;
 537                 ip->ip_len += iphlen;
 538                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
 539                 INP_INFO_RUNLOCK(&V_udbinfo);
 540                 return;
 541         }
 542
 543         /*
 544          * Check the minimum TTL for socket.
 545          */
 546         INP_RLOCK(inp);
 547         INP_INFO_RUNLOCK(&V_udbinfo);
 548         if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
 549                 INP_RUNLOCK(inp);
 550                 goto badunlocked;
 551         }
 552         udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in);
 553         INP_RUNLOCK(inp);
 554         return;
 555
 556 badheadlocked:
 557         if (inp)
 558                 INP_RUNLOCK(inp);
 559         INP_INFO_RUNLOCK(&V_udbinfo);
 560 badunlocked:
 561         m_freem(m);
 562 }
 563
 564 /*
 565  * Notify a udp user of an asynchronous error; just wake up so that they can
 566  * collect error status.
 567  */
 568 struct inpcb *
 569 udp_notify(struct inpcb *inp, int errno)
 570 {
 571
 572         /*
 573          * While udp_ctlinput() always calls udp_notify() with a read lock
 574          * when invoking it directly, in_pcbnotifyall() currently uses write
 575          * locks due to sharing code with TCP.  For now, accept either a read
 576          * or a write lock, but a read lock is sufficient.
 577          */
 578         INP_LOCK_ASSERT(inp);
 579
 580         inp->inp_socket->so_error = errno;
 581         sorwakeup(inp->inp_socket);
 582         sowwakeup(inp->inp_socket);
 583         return (inp);
 584 }
 585
 586 void
 587 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 588 {
 589         struct ip *ip = vip;
 590         struct udphdr *uh;
 591         struct in_addr faddr;
 592         struct inpcb *inp;
 593
 594         faddr = ((struct sockaddr_in *)sa)->sin_addr;
 595         if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
 596                 return;
 597
 598         /*
 599          * Redirects don't need to be handled up here.
 600          */
 601         if (PRC_IS_REDIRECT(cmd))
 602                 return;
 603
 604         /*
 605          * Hostdead is ugly because it goes linearly through all PCBs.
 606          *
 607          * XXX: We never get this from ICMP, otherwise it makes an excellent
 608          * DoS attack on machines with many connections.
 609          */
 610         if (cmd == PRC_HOSTDEAD)
 611                 ip = NULL;
 612         else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
 613                 return;
 614         if (ip != NULL) {
 615                 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 616                 INP_INFO_RLOCK(&V_udbinfo);
 617                 inp = in_pcblookup_hash(&V_udbinfo, faddr, uh->uh_dport,
 618                     ip->ip_src, uh->uh_sport, 0, NULL);
 619                 if (inp != NULL) {
 620                         INP_RLOCK(inp);
 621                         if (inp->inp_socket != NULL) {
 622                                 udp_notify(inp, inetctlerrmap[cmd]);
 623                         }
 624                         INP_RUNLOCK(inp);
 625                 }
 626                 INP_INFO_RUNLOCK(&V_udbinfo);
 627         } else
 628                 in_pcbnotifyall(&V_udbinfo, faddr, inetctlerrmap[cmd],
 629                     udp_notify);
 630 }
 631
 632 static int
 633 udp_pcblist(SYSCTL_HANDLER_ARGS)
 634 {
 635         int error, i, n;
 636         struct inpcb *inp, **inp_list;
 637         inp_gen_t gencnt;
 638         struct xinpgen xig;
 639
 640         /*
 641          * The process of preparing the PCB list is too time-consuming and
 642          * resource-intensive to repeat twice on every request.
 643          */
 644         if (req->oldptr == 0) {
 645                 n = V_udbinfo.ipi_count;
 646                 req->oldidx = 2 * (sizeof xig)
 647                         + (n + n/8) * sizeof(struct xinpcb);
 648                 return (0);
 649         }
 650
 651         if (req->newptr != 0)
 652                 return (EPERM);
 653
 654         /*
 655          * OK, now we're committed to doing something.
 656          */
 657         INP_INFO_RLOCK(&V_udbinfo);
 658         gencnt = V_udbinfo.ipi_gencnt;
 659         n = V_udbinfo.ipi_count;
 660         INP_INFO_RUNLOCK(&V_udbinfo);
 661
 662         error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
 663                 + n * sizeof(struct xinpcb));
 664         if (error != 0)
 665                 return (error);
 666
 667         xig.xig_len = sizeof xig;
 668         xig.xig_count = n;
 669         xig.xig_gen = gencnt;
 670         xig.xig_sogen = so_gencnt;
 671         error = SYSCTL_OUT(req, &xig, sizeof xig);
 672         if (error)
 673                 return (error);
 674
 675         inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
 676         if (inp_list == 0)
 677                 return (ENOMEM);
 678
 679         INP_INFO_RLOCK(&V_udbinfo);
 680         for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n;
 681              inp = LIST_NEXT(inp, inp_list)) {
 682                 INP_RLOCK(inp);
 683                 if (inp->inp_gencnt <= gencnt &&
 684                     cr_canseesocket(req->td->td_ucred, inp->inp_socket) == 0)
 685                         inp_list[i++] = inp;
 686                 INP_RUNLOCK(inp);
 687         }
 688         INP_INFO_RUNLOCK(&V_udbinfo);
 689         n = i;
 690
 691         error = 0;
 692         for (i = 0; i < n; i++) {
 693                 inp = inp_list[i];
 694                 INP_RLOCK(inp);
 695                 if (inp->inp_gencnt <= gencnt) {
 696                         struct xinpcb xi;
 697                         bzero(&xi, sizeof(xi));
 698                         xi.xi_len = sizeof xi;
 699                         /* XXX should avoid extra copy */
 700                         bcopy(inp, &xi.xi_inp, sizeof *inp);
 701                         if (inp->inp_socket)
 702                                 sotoxsocket(inp->inp_socket, &xi.xi_socket);
 703                         xi.xi_inp.inp_gencnt = inp->inp_gencnt;
 704                         INP_RUNLOCK(inp);
 705                         error = SYSCTL_OUT(req, &xi, sizeof xi);
 706                 } else
 707                         INP_RUNLOCK(inp);
 708         }
 709         if (!error) {
 710                 /*
 711                  * Give the user an updated idea of our state.  If the
 712                  * generation differs from what we told her before, she knows
 713                  * that something happened while we were processing this
 714                  * request, and it might be necessary to retry.
 715                  */
 716                 INP_INFO_RLOCK(&V_udbinfo);
 717                 xig.xig_gen = V_udbinfo.ipi_gencnt;
 718                 xig.xig_sogen = so_gencnt;
 719                 xig.xig_count = V_udbinfo.ipi_count;
 720                 INP_INFO_RUNLOCK(&V_udbinfo);
 721                 error = SYSCTL_OUT(req, &xig, sizeof xig);
 722         }
 723         free(inp_list, M_TEMP);
 724         return (error);
 725 }
 726
 727 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0,
 728     udp_pcblist, "S,xinpcb", "List of active UDP sockets");
 729
 730 static int
 731 udp_getcred(SYSCTL_HANDLER_ARGS)
 732 {
 733         struct xucred xuc;
 734         struct sockaddr_in addrs[2];
 735         struct inpcb *inp;
 736         int error;
 737
 738         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 739         if (error)
 740                 return (error);
 741         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 742         if (error)
 743                 return (error);
 744         INP_INFO_RLOCK(&V_udbinfo);
 745         inp = in_pcblookup_hash(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
 746                                 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL);
 747         if (inp != NULL) {
 748                 INP_RLOCK(inp);
 749                 INP_INFO_RUNLOCK(&V_udbinfo);
 750                 if (inp->inp_socket == NULL)
 751                         error = ENOENT;
 752                 if (error == 0)
 753                         error = cr_canseesocket(req->td->td_ucred,
 754                             inp->inp_socket);
 755                 if (error == 0)
 756                         cru2x(inp->inp_socket->so_cred, &xuc);
 757                 INP_RUNLOCK(inp);
 758         } else {
 759                 INP_INFO_RUNLOCK(&V_udbinfo);
 760                 error = ENOENT;
 761         }
 762         if (error == 0)
 763                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 764         return (error);
 765 }
 766
 767 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
 768     CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
 769     udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
 770
 771 static int
 772 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
 773     struct mbuf *control, struct thread *td)
 774 {
 775         struct udpiphdr *ui;
 776         int len = m->m_pkthdr.len;
 777         struct in_addr faddr, laddr;
 778         struct cmsghdr *cm;
 779         struct sockaddr_in *sin, src;
 780         int error = 0;
 781         int ipflags;
 782         u_short fport, lport;
 783         int unlock_udbinfo;
 784
 785         /*
 786          * udp_output() may need to temporarily bind or connect the current
 787          * inpcb.  As such, we don't know up front whether we will need the
 788          * pcbinfo lock or not.  Do any work to decide what is needed up
 789          * front before acquiring any locks.
 790          */
 791         if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
 792                 if (control)
 793                         m_freem(control);
 794                 m_freem(m);
 795                 return (EMSGSIZE);
 796         }
 797
 798         src.sin_family = 0;
 799         if (control != NULL) {
 800                 /*
 801                  * XXX: Currently, we assume all the optional information is
 802                  * stored in a single mbuf.
 803                  */
 804                 if (control->m_next) {
 805                         m_freem(control);
 806                         m_freem(m);
 807                         return (EINVAL);
 808                 }
 809                 for (; control->m_len > 0;
 810                     control->m_data += CMSG_ALIGN(cm->cmsg_len),
 811                     control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
 812                         cm = mtod(control, struct cmsghdr *);
 813                         if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
 814                             || cm->cmsg_len > control->m_len) {
 815                                 error = EINVAL;
 816                                 break;
 817                         }
 818                         if (cm->cmsg_level != IPPROTO_IP)
 819                                 continue;
 820
 821                         switch (cm->cmsg_type) {
 822                         case IP_SENDSRCADDR:
 823                                 if (cm->cmsg_len !=
 824                                     CMSG_LEN(sizeof(struct in_addr))) {
 825                                         error = EINVAL;
 826                                         break;
 827                                 }
 828                                 bzero(&src, sizeof(src));
 829                                 src.sin_family = AF_INET;
 830                                 src.sin_len = sizeof(src);
 831                                 src.sin_port = inp->inp_lport;
 832                                 src.sin_addr =
 833                                     *(struct in_addr *)CMSG_DATA(cm);
 834                                 break;
 835
 836                         default:
 837                                 error = ENOPROTOOPT;
 838                                 break;
 839                         }
 840                         if (error)
 841                                 break;
 842                 }
 843                 m_freem(control);
 844         }
 845         if (error) {
 846                 m_freem(m);
 847                 return (error);
 848         }
 849
 850         /*
 851          * Depending on whether or not the application has bound or connected
 852          * the socket, we may have to do varying levels of work.  The optimal
 853          * case is for a connected UDP socket, as a global lock isn't
 854          * required at all.
 855          *
 856          * In order to decide which we need, we require stability of the
 857          * inpcb binding, which we ensure by acquiring a read lock on the
 858          * inpcb.  This doesn't strictly follow the lock order, so we play
 859          * the trylock and retry game; note that we may end up with more
 860          * conservative locks than required the second time around, so later
 861          * assertions have to accept that.  Further analysis of the number of
 862          * misses under contention is required.
 863          */
 864         sin = (struct sockaddr_in *)addr;
 865         INP_RLOCK(inp);
 866         if (sin != NULL &&
 867             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
 868                 INP_RUNLOCK(inp);
 869                 INP_INFO_WLOCK(&V_udbinfo);
 870                 INP_WLOCK(inp);
 871                 unlock_udbinfo = 2;
 872         } else if ((sin != NULL && (
 873             (sin->sin_addr.s_addr == INADDR_ANY) ||
 874             (sin->sin_addr.s_addr == INADDR_BROADCAST) ||
 875             (inp->inp_laddr.s_addr == INADDR_ANY) ||
 876             (inp->inp_lport == 0))) ||
 877             (src.sin_family == AF_INET)) {
 878                 if (!INP_INFO_TRY_RLOCK(&V_udbinfo)) {
 879                         INP_RUNLOCK(inp);
 880                         INP_INFO_RLOCK(&V_udbinfo);
 881                         INP_RLOCK(inp);
 882                 }
 883                 unlock_udbinfo = 1;
 884         } else
 885                 unlock_udbinfo = 0;
 886
 887         /*
 888          * If the IP_SENDSRCADDR control message was specified, override the
 889          * source address for this datagram.  Its use is invalidated if the
 890          * address thus specified is incomplete or clobbers other inpcbs.
 891          */
 892         laddr = inp->inp_laddr;
 893         lport = inp->inp_lport;
 894         if (src.sin_family == AF_INET) {
 895                 INP_INFO_LOCK_ASSERT(&V_udbinfo);
 896                 if ((lport == 0) ||
 897                     (laddr.s_addr == INADDR_ANY &&
 898                      src.sin_addr.s_addr == INADDR_ANY)) {
 899                         error = EINVAL;
 900                         goto release;
 901                 }
 902                 error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
 903                     &laddr.s_addr, &lport, td->td_ucred);
 904                 if (error)
 905                         goto release;
 906         }
 907
 908         /*
 909          * If a UDP socket has been connected, then a local address/port will
 910          * have been selected and bound.
 911          *
 912          * If a UDP socket has not been connected to, then an explicit
 913          * destination address must be used, in which case a local
 914          * address/port may not have been selected and bound.
 915          */
 916         if (sin != NULL) {
 917                 INP_LOCK_ASSERT(inp);
 918                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
 919                         error = EISCONN;
 920                         goto release;
 921                 }
 922
 923                 /*
 924                  * Jail may rewrite the destination address, so let it do
 925                  * that before we use it.
 926                  */
 927                 if (jailed(td->td_ucred))
 928                         prison_remote_ip(td->td_ucred, 0,
 929                             &sin->sin_addr.s_addr);
 930
 931                 /*
 932                  * If a local address or port hasn't yet been selected, or if
 933                  * the destination address needs to be rewritten due to using
 934                  * a special INADDR_ constant, invoke in_pcbconnect_setup()
 935                  * to do the heavy lifting.  Once a port is selected, we
 936                  * commit the binding back to the socket; we also commit the
 937                  * binding of the address if in jail.
 938                  *
 939                  * If we already have a valid binding and we're not
 940                  * requesting a destination address rewrite, use a fast path.
 941                  */
 942                 if (inp->inp_laddr.s_addr == INADDR_ANY ||
 943                     inp->inp_lport == 0 ||
 944                     sin->sin_addr.s_addr == INADDR_ANY ||
 945                     sin->sin_addr.s_addr == INADDR_BROADCAST) {
 946                         INP_INFO_LOCK_ASSERT(&V_udbinfo);
 947                         error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
 948                             &lport, &faddr.s_addr, &fport, NULL,
 949                             td->td_ucred);
 950                         if (error)
 951                                 goto release;
 952
 953                         /*
 954                          * XXXRW: Why not commit the port if the address is
 955                          * !INADDR_ANY?
 956                          */
 957                         /* Commit the local port if newly assigned. */
 958                         if (inp->inp_laddr.s_addr == INADDR_ANY &&
 959                             inp->inp_lport == 0) {
 960                                 INP_INFO_WLOCK_ASSERT(&V_udbinfo);
 961                                 INP_WLOCK_ASSERT(inp);
 962                                 /*
 963                                  * Remember addr if jailed, to prevent
 964                                  * rebinding.
 965                                  */
 966                                 if (jailed(td->td_ucred))
 967                                         inp->inp_laddr = laddr;
 968                                 inp->inp_lport = lport;
 969                                 if (in_pcbinshash(inp) != 0) {
 970                                         inp->inp_lport = 0;
 971                                         error = EAGAIN;
 972                                         goto release;
 973                                 }
 974                                 inp->inp_flags |= INP_ANONPORT;
 975                         }
 976                 } else {
 977                         faddr = sin->sin_addr;
 978                         fport = sin->sin_port;
 979                 }
 980         } else {
 981                 INP_LOCK_ASSERT(inp);
 982                 faddr = inp->inp_faddr;
 983                 fport = inp->inp_fport;
 984                 if (faddr.s_addr == INADDR_ANY) {
 985                         error = ENOTCONN;
 986                         goto release;
 987                 }
 988         }
 989
 990         /*
 991          * Calculate data length and get a mbuf for UDP, IP, and possible
 992          * link-layer headers.  Immediate slide the data pointer back forward
 993          * since we won't use that space at this layer.
 994          */
 995         M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT);
 996         if (m == NULL) {
 997                 error = ENOBUFS;
 998                 goto release;
 999         }
1000         m->m_data += max_linkhdr;
1001         m->m_len -= max_linkhdr;
1002         m->m_pkthdr.len -= max_linkhdr;
1003
1004         /*
1005          * Fill in mbuf with extended UDP header and addresses and length put
1006          * into network format.
1007          */
1008         ui = mtod(m, struct udpiphdr *);
1009         bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1010         ui->ui_pr = IPPROTO_UDP;
1011         ui->ui_src = laddr;
1012         ui->ui_dst = faddr;
1013         ui->ui_sport = lport;
1014         ui->ui_dport = fport;
1015         ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1016
1017         /*
1018          * Set the Don't Fragment bit in the IP header.
1019          */
1020         if (inp->inp_flags & INP_DONTFRAG) {
1021                 struct ip *ip;
1022
1023                 ip = (struct ip *)&ui->ui_i;
1024                 ip->ip_off |= IP_DF;
1025         }
1026
1027         ipflags = 0;
1028         if (inp->inp_socket->so_options & SO_DONTROUTE)
1029                 ipflags |= IP_ROUTETOIF;
1030         if (inp->inp_socket->so_options & SO_BROADCAST)
1031                 ipflags |= IP_ALLOWBROADCAST;
1032         if (inp->inp_flags & INP_ONESBCAST)
1033                 ipflags |= IP_SENDONES;
1034
1035 #ifdef MAC
1036         mac_inpcb_create_mbuf(inp, m);
1037 #endif
1038
1039         /*
1040          * Set up checksum and output datagram.
1041          */
1042         if (udp_cksum) {
1043                 if (inp->inp_flags & INP_ONESBCAST)
1044                         faddr.s_addr = INADDR_BROADCAST;
1045                 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1046                     htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP));
1047                 m->m_pkthdr.csum_flags = CSUM_UDP;
1048                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1049         } else
1050                 ui->ui_sum = 0;
1051         ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len;
1052         ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1053         ((struct ip *)ui)->ip_tos = inp->inp_ip_tos;    /* XXX */
1054         V_udpstat.udps_opackets++;
1055
1056         if (unlock_udbinfo == 2)
1057                 INP_INFO_WUNLOCK(&V_udbinfo);
1058         else if (unlock_udbinfo == 1)
1059                 INP_INFO_RUNLOCK(&V_udbinfo);
1060         error = ip_output(m, inp->inp_options, NULL, ipflags,
1061             inp->inp_moptions, inp);
1062         if (unlock_udbinfo == 2)
1063                 INP_WUNLOCK(inp);
1064         else
1065                 INP_RUNLOCK(inp);
1066         return (error);
1067
1068 release:
1069         if (unlock_udbinfo == 2) {
1070                 INP_WUNLOCK(inp);
1071                 INP_INFO_WUNLOCK(&V_udbinfo);
1072         } else if (unlock_udbinfo == 1) {
1073                 INP_RUNLOCK(inp);
1074                 INP_INFO_RUNLOCK(&V_udbinfo);
1075         } else
1076                 INP_RUNLOCK(inp);
1077         m_freem(m);
1078         return (error);
1079 }
1080
1081 static void
1082 udp_abort(struct socket *so)
1083 {
1084         struct inpcb *inp;
1085
1086         inp = sotoinpcb(so);
1087         KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1088         INP_INFO_WLOCK(&V_udbinfo);
1089         INP_WLOCK(inp);
1090         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1091                 in_pcbdisconnect(inp);
1092                 inp->inp_laddr.s_addr = INADDR_ANY;
1093                 soisdisconnected(so);
1094         }
1095         INP_WUNLOCK(inp);
1096         INP_INFO_WUNLOCK(&V_udbinfo);
1097 }
1098
1099 static int
1100 udp_attach(struct socket *so, int proto, struct thread *td)
1101 {
1102         struct inpcb *inp;
1103         int error;
1104
1105         inp = sotoinpcb(so);
1106         KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1107         error = soreserve(so, udp_sendspace, udp_recvspace);
1108         if (error)
1109                 return (error);
1110         INP_INFO_WLOCK(&V_udbinfo);
1111         error = in_pcballoc(so, &V_udbinfo);
1112         if (error) {
1113                 INP_INFO_WUNLOCK(&V_udbinfo);
1114                 return (error);
1115         }
1116
1117         inp = (struct inpcb *)so->so_pcb;
1118         INP_INFO_WUNLOCK(&V_udbinfo);
1119         inp->inp_vflag |= INP_IPV4;
1120         inp->inp_ip_ttl = V_ip_defttl;
1121         INP_WUNLOCK(inp);
1122         return (0);
1123 }
1124
1125 static int
1126 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1127 {
1128         struct inpcb *inp;
1129         int error;
1130
1131         inp = sotoinpcb(so);
1132         KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1133         INP_INFO_WLOCK(&V_udbinfo);
1134         INP_WLOCK(inp);
1135         error = in_pcbbind(inp, nam, td->td_ucred);
1136         INP_WUNLOCK(inp);
1137         INP_INFO_WUNLOCK(&V_udbinfo);
1138         return (error);
1139 }
1140
1141 static void
1142 udp_close(struct socket *so)
1143 {
1144         struct inpcb *inp;
1145
1146         inp = sotoinpcb(so);
1147         KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1148         INP_INFO_WLOCK(&V_udbinfo);
1149         INP_WLOCK(inp);
1150         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1151                 in_pcbdisconnect(inp);
1152                 inp->inp_laddr.s_addr = INADDR_ANY;
1153                 soisdisconnected(so);
1154         }
1155         INP_WUNLOCK(inp);
1156         INP_INFO_WUNLOCK(&V_udbinfo);
1157 }
1158
1159 static int
1160 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1161 {
1162         struct inpcb *inp;
1163         int error;
1164         struct sockaddr_in *sin;
1165
1166         inp = sotoinpcb(so);
1167         KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1168         INP_INFO_WLOCK(&V_udbinfo);
1169         INP_WLOCK(inp);
1170         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1171                 INP_WUNLOCK(inp);
1172                 INP_INFO_WUNLOCK(&V_udbinfo);
1173                 return (EISCONN);
1174         }
1175         sin = (struct sockaddr_in *)nam;
1176         if (jailed(td->td_ucred))
1177                 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr);
1178         error = in_pcbconnect(inp, nam, td->td_ucred);
1179         if (error == 0)
1180                 soisconnected(so);
1181         INP_WUNLOCK(inp);
1182         INP_INFO_WUNLOCK(&V_udbinfo);
1183         return (error);
1184 }
1185
1186 static void
1187 udp_detach(struct socket *so)
1188 {
1189         struct inpcb *inp;
1190
1191         inp = sotoinpcb(so);
1192         KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1193         KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1194             ("udp_detach: not disconnected"));
1195         INP_INFO_WLOCK(&V_udbinfo);
1196         INP_WLOCK(inp);
1197         in_pcbdetach(inp);
1198         in_pcbfree(inp);
1199         INP_INFO_WUNLOCK(&V_udbinfo);
1200 }
1201
1202 static int
1203 udp_disconnect(struct socket *so)
1204 {
1205         struct inpcb *inp;
1206
1207         inp = sotoinpcb(so);
1208         KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1209         INP_INFO_WLOCK(&V_udbinfo);
1210         INP_WLOCK(inp);
1211         if (inp->inp_faddr.s_addr == INADDR_ANY) {
1212                 INP_WUNLOCK(inp);
1213                 INP_INFO_WUNLOCK(&V_udbinfo);
1214                 return (ENOTCONN);
1215         }
1216
1217         in_pcbdisconnect(inp);
1218         inp->inp_laddr.s_addr = INADDR_ANY;
1219         SOCK_LOCK(so);
1220         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1221         SOCK_UNLOCK(so);
1222         INP_WUNLOCK(inp);
1223         INP_INFO_WUNLOCK(&V_udbinfo);
1224         return (0);
1225 }
1226
1227 static int
1228 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1229     struct mbuf *control, struct thread *td)
1230 {
1231         struct inpcb *inp;
1232
1233         inp = sotoinpcb(so);
1234         KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1235         return (udp_output(inp, m, addr, control, td));
1236 }
1237
1238 int
1239 udp_shutdown(struct socket *so)
1240 {
1241         struct inpcb *inp;
1242
1243         inp = sotoinpcb(so);
1244         KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1245         INP_WLOCK(inp);
1246         socantsendmore(so);
1247         INP_WUNLOCK(inp);
1248         return (0);
1249 }
1250
1251 struct pr_usrreqs udp_usrreqs = {
1252         .pru_abort =            udp_abort,
1253         .pru_attach =           udp_attach,
1254         .pru_bind =             udp_bind,
1255         .pru_connect =          udp_connect,
1256         .pru_control =          in_control,
1257         .pru_detach =           udp_detach,
1258         .pru_disconnect =       udp_disconnect,
1259         .pru_peeraddr =         in_getpeeraddr,
1260         .pru_send =             udp_send,
1261         .pru_soreceive =        soreceive_dgram,
1262         .pru_sosend =           sosend_dgram,
1263         .pru_shutdown =         udp_shutdown,
1264         .pru_sockaddr =         in_getsockaddr,
1265         .pru_sosetlabel =       in_pcbsosetlabel,
1266         .pru_close =            udp_close,
1267 };