sys/netinet/udp_usrreq.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
   5  *      The Regents of the University of California.
   6  * Copyright (c) 2008 Robert N. M. Watson
   7  * Copyright (c) 2010-2011 Juniper Networks, Inc.
   8  * Copyright (c) 2014 Kevin Lo
   9  * All rights reserved.
  10  *
  11  * Portions of this software were developed by Robert N. M. Watson under
  12  * contract to Juniper Networks, Inc.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  * 3. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      @(#)udp_usrreq.c        8.6 (Berkeley) 5/23/95
  39  */
  40
  41 #include <sys/cdefs.h>
  42 __FBSDID("$FreeBSD$");
  43
  44 #include "opt_inet.h"
  45 #include "opt_inet6.h"
  46 #include "opt_ipsec.h"
  47 #include "opt_rss.h"
  48
  49 #include <sys/param.h>
  50 #include <sys/domain.h>
  51 #include <sys/eventhandler.h>
  52 #include <sys/jail.h>
  53 #include <sys/kernel.h>
  54 #include <sys/lock.h>
  55 #include <sys/malloc.h>
  56 #include <sys/mbuf.h>
  57 #include <sys/priv.h>
  58 #include <sys/proc.h>
  59 #include <sys/protosw.h>
  60 #include <sys/sdt.h>
  61 #include <sys/signalvar.h>
  62 #include <sys/socket.h>
  63 #include <sys/socketvar.h>
  64 #include <sys/sx.h>
  65 #include <sys/sysctl.h>
  66 #include <sys/syslog.h>
  67 #include <sys/systm.h>
  68
  69 #include <vm/uma.h>
  70
  71 #include <net/if.h>
  72 #include <net/if_var.h>
  73 #include <net/route.h>
  74 #include <net/rss_config.h>
  75
  76 #include <netinet/in.h>
  77 #include <netinet/in_kdtrace.h>
  78 #include <netinet/in_pcb.h>
  79 #include <netinet/in_systm.h>
  80 #include <netinet/in_var.h>
  81 #include <netinet/ip.h>
  82 #ifdef INET6
  83 #include <netinet/ip6.h>
  84 #endif
  85 #include <netinet/ip_icmp.h>
  86 #include <netinet/icmp_var.h>
  87 #include <netinet/ip_var.h>
  88 #include <netinet/ip_options.h>
  89 #ifdef INET6
  90 #include <netinet6/ip6_var.h>
  91 #endif
  92 #include <netinet/udp.h>
  93 #include <netinet/udp_var.h>
  94 #include <netinet/udplite.h>
  95 #include <netinet/in_rss.h>
  96
  97 #include <netipsec/ipsec_support.h>
  98
  99 #include <machine/in_cksum.h>
 100
 101 #include <security/mac/mac_framework.h>
 102
 103 /*
 104  * UDP and UDP-Lite protocols implementation.
 105  * Per RFC 768, August, 1980.
 106  * Per RFC 3828, July, 2004.
 107  */
 108
 109 /*
 110  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
 111  * removes the only data integrity mechanism for packets and malformed
 112  * packets that would otherwise be discarded due to bad checksums, and may
 113  * cause problems (especially for NFS data blocks).
 114  */
 115 VNET_DEFINE(int, udp_cksum) = 1;
 116 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
 117     &VNET_NAME(udp_cksum), 0, "compute udp checksum");
 118
 119 int     udp_log_in_vain = 0;
 120 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW,
 121     &udp_log_in_vain, 0, "Log all incoming UDP packets");
 122
 123 VNET_DEFINE(int, udp_blackhole) = 0;
 124 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
 125     &VNET_NAME(udp_blackhole), 0,
 126     "Do not send port unreachables for refused connects");
 127
 128 u_long  udp_sendspace = 9216;           /* really max datagram size */
 129 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
 130     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
 131
 132 u_long  udp_recvspace = 40 * (1024 +
 133 #ifdef INET6
 134                                       sizeof(struct sockaddr_in6)
 135 #else
 136                                       sizeof(struct sockaddr_in)
 137 #endif
 138                                       );        /* 40 1K datagrams */
 139
 140 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
 141     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
 142
 143 VNET_DEFINE(struct inpcbhead, udb);             /* from udp_var.h */
 144 VNET_DEFINE(struct inpcbinfo, udbinfo);
 145 VNET_DEFINE(struct inpcbhead, ulitecb);
 146 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
 147 VNET_DEFINE_STATIC(uma_zone_t, udpcb_zone);
 148 #define V_udpcb_zone                    VNET(udpcb_zone)
 149
 150 #ifndef UDBHASHSIZE
 151 #define UDBHASHSIZE     128
 152 #endif
 153
 154 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat);          /* from udp_var.h */
 155 VNET_PCPUSTAT_SYSINIT(udpstat);
 156 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
 157     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
 158
 159 #ifdef VIMAGE
 160 VNET_PCPUSTAT_SYSUNINIT(udpstat);
 161 #endif /* VIMAGE */
 162 #ifdef INET
 163 static void     udp_detach(struct socket *so);
 164 static int      udp_output(struct inpcb *, struct mbuf *, struct sockaddr *,
 165                     struct mbuf *, struct thread *);
 166 #endif
 167
 168 static void
 169 udp_zone_change(void *tag)
 170 {
 171
 172         uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets);
 173         uma_zone_set_max(V_udpcb_zone, maxsockets);
 174 }
 175
 176 static int
 177 udp_inpcb_init(void *mem, int size, int flags)
 178 {
 179         struct inpcb *inp;
 180
 181         inp = mem;
 182         INP_LOCK_INIT(inp, "inp", "udpinp");
 183         return (0);
 184 }
 185
 186 static int
 187 udplite_inpcb_init(void *mem, int size, int flags)
 188 {
 189         struct inpcb *inp;
 190
 191         inp = mem;
 192         INP_LOCK_INIT(inp, "inp", "udpliteinp");
 193         return (0);
 194 }
 195
 196 void
 197 udp_init(void)
 198 {
 199
 200         /*
 201          * For now default to 2-tuple UDP hashing - until the fragment
 202          * reassembly code can also update the flowid.
 203          *
 204          * Once we can calculate the flowid that way and re-establish
 205          * a 4-tuple, flip this to 4-tuple.
 206          */
 207         in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE,
 208             "udp_inpcb", udp_inpcb_init, IPI_HASHFIELDS_2TUPLE);
 209         V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb),
 210             NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
 211         uma_zone_set_max(V_udpcb_zone, maxsockets);
 212         uma_zone_set_warning(V_udpcb_zone, "kern.ipc.maxsockets limit reached");
 213         EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL,
 214             EVENTHANDLER_PRI_ANY);
 215 }
 216
 217 void
 218 udplite_init(void)
 219 {
 220
 221         in_pcbinfo_init(&V_ulitecbinfo, "udplite", &V_ulitecb, UDBHASHSIZE,
 222             UDBHASHSIZE, "udplite_inpcb", udplite_inpcb_init,
 223             IPI_HASHFIELDS_2TUPLE);
 224 }
 225
 226 /*
 227  * Kernel module interface for updating udpstat.  The argument is an index
 228  * into udpstat treated as an array of u_long.  While this encodes the
 229  * general layout of udpstat into the caller, it doesn't encode its location,
 230  * so that future changes to add, for example, per-CPU stats support won't
 231  * cause binary compatibility problems for kernel modules.
 232  */
 233 void
 234 kmod_udpstat_inc(int statnum)
 235 {
 236
 237         counter_u64_add(VNET(udpstat)[statnum], 1);
 238 }
 239
 240 int
 241 udp_newudpcb(struct inpcb *inp)
 242 {
 243         struct udpcb *up;
 244
 245         up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO);
 246         if (up == NULL)
 247                 return (ENOBUFS);
 248         inp->inp_ppcb = up;
 249         return (0);
 250 }
 251
 252 void
 253 udp_discardcb(struct udpcb *up)
 254 {
 255
 256         uma_zfree(V_udpcb_zone, up);
 257 }
 258
 259 #ifdef VIMAGE
 260 static void
 261 udp_destroy(void *unused __unused)
 262 {
 263
 264         in_pcbinfo_destroy(&V_udbinfo);
 265         uma_zdestroy(V_udpcb_zone);
 266 }
 267 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
 268
 269 static void
 270 udplite_destroy(void *unused __unused)
 271 {
 272
 273         in_pcbinfo_destroy(&V_ulitecbinfo);
 274 }
 275 VNET_SYSUNINIT(udplite, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udplite_destroy,
 276     NULL);
 277 #endif
 278
 279 #ifdef INET
 280 /*
 281  * Subroutine of udp_input(), which appends the provided mbuf chain to the
 282  * passed pcb/socket.  The caller must provide a sockaddr_in via udp_in that
 283  * contains the source address.  If the socket ends up being an IPv6 socket,
 284  * udp_append() will convert to a sockaddr_in6 before passing the address
 285  * into the socket code.
 286  *
 287  * In the normal case udp_append() will return 0, indicating that you
 288  * must unlock the inp. However if a tunneling protocol is in place we increment
 289  * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
 290  * then decrement the reference count. If the inp_rele returns 1, indicating the
 291  * inp is gone, we return that to the caller to tell them *not* to unlock
 292  * the inp. In the case of multi-cast this will cause the distribution
 293  * to stop (though most tunneling protocols known currently do *not* use
 294  * multicast).
 295  */
 296 static int
 297 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
 298     struct sockaddr_in *udp_in)
 299 {
 300         struct sockaddr *append_sa;
 301         struct socket *so;
 302         struct mbuf *tmpopts, *opts = NULL;
 303 #ifdef INET6
 304         struct sockaddr_in6 udp_in6;
 305 #endif
 306         struct udpcb *up;
 307
 308         INP_LOCK_ASSERT(inp);
 309
 310         /*
 311          * Engage the tunneling protocol.
 312          */
 313         up = intoudpcb(inp);
 314         if (up->u_tun_func != NULL) {
 315                 in_pcbref(inp);
 316                 INP_RUNLOCK(inp);
 317                 (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
 318                     up->u_tun_ctx);
 319                 INP_RLOCK(inp);
 320                 return (in_pcbrele_rlocked(inp));
 321         }
 322
 323         off += sizeof(struct udphdr);
 324
 325 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 326         /* Check AH/ESP integrity. */
 327         if (IPSEC_ENABLED(ipv4) &&
 328             IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
 329                 m_freem(n);
 330                 return (0);
 331         }
 332         if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
 333                 if (IPSEC_ENABLED(ipv4) &&
 334                     UDPENCAP_INPUT(n, off, AF_INET) != 0)
 335                         return (0);     /* Consumed. */
 336         }
 337 #endif /* IPSEC */
 338 #ifdef MAC
 339         if (mac_inpcb_check_deliver(inp, n) != 0) {
 340                 m_freem(n);
 341                 return (0);
 342         }
 343 #endif /* MAC */
 344         if (inp->inp_flags & INP_CONTROLOPTS ||
 345             inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
 346 #ifdef INET6
 347                 if (inp->inp_vflag & INP_IPV6)
 348                         (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
 349                 else
 350 #endif /* INET6 */
 351                         ip_savecontrol(inp, &opts, ip, n);
 352         }
 353         if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
 354                 tmpopts = sbcreatecontrol((caddr_t)&udp_in[1],
 355                         sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP);
 356                 if (tmpopts) {
 357                         if (opts) {
 358                                 tmpopts->m_next = opts;
 359                                 opts = tmpopts;
 360                         } else
 361                                 opts = tmpopts;
 362                 }
 363         }
 364 #ifdef INET6
 365         if (inp->inp_vflag & INP_IPV6) {
 366                 bzero(&udp_in6, sizeof(udp_in6));
 367                 udp_in6.sin6_len = sizeof(udp_in6);
 368                 udp_in6.sin6_family = AF_INET6;
 369                 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
 370                 append_sa = (struct sockaddr *)&udp_in6;
 371         } else
 372 #endif /* INET6 */
 373                 append_sa = (struct sockaddr *)&udp_in[0];
 374         m_adj(n, off);
 375
 376         so = inp->inp_socket;
 377         SOCKBUF_LOCK(&so->so_rcv);
 378         if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
 379                 SOCKBUF_UNLOCK(&so->so_rcv);
 380                 m_freem(n);
 381                 if (opts)
 382                         m_freem(opts);
 383                 UDPSTAT_INC(udps_fullsock);
 384         } else
 385                 sorwakeup_locked(so);
 386         return (0);
 387 }
 388
 389 int
 390 udp_input(struct mbuf **mp, int *offp, int proto)
 391 {
 392         struct ip *ip;
 393         struct udphdr *uh;
 394         struct ifnet *ifp;
 395         struct inpcb *inp;
 396         uint16_t len, ip_len;
 397         struct inpcbinfo *pcbinfo;
 398         struct ip save_ip;
 399         struct sockaddr_in udp_in[2];
 400         struct mbuf *m;
 401         struct m_tag *fwd_tag;
 402         struct epoch_tracker et;
 403         int cscov_partial, iphlen;
 404
 405         m = *mp;
 406         iphlen = *offp;
 407         ifp = m->m_pkthdr.rcvif;
 408         *mp = NULL;
 409         UDPSTAT_INC(udps_ipackets);
 410
 411         /*
 412          * Strip IP options, if any; should skip this, make available to
 413          * user, and use on returned packets, but we don't yet have a way to
 414          * check the checksum with options still present.
 415          */
 416         if (iphlen > sizeof (struct ip)) {
 417                 ip_stripoptions(m);
 418                 iphlen = sizeof(struct ip);
 419         }
 420
 421         /*
 422          * Get IP and UDP header together in first mbuf.
 423          */
 424         ip = mtod(m, struct ip *);
 425         if (m->m_len < iphlen + sizeof(struct udphdr)) {
 426                 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
 427                         UDPSTAT_INC(udps_hdrops);
 428                         return (IPPROTO_DONE);
 429                 }
 430                 ip = mtod(m, struct ip *);
 431         }
 432         uh = (struct udphdr *)((caddr_t)ip + iphlen);
 433         cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
 434
 435         /*
 436          * Destination port of 0 is illegal, based on RFC768.
 437          */
 438         if (uh->uh_dport == 0)
 439                 goto badunlocked;
 440
 441         /*
 442          * Construct sockaddr format source address.  Stuff source address
 443          * and datagram in user buffer.
 444          */
 445         bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
 446         udp_in[0].sin_len = sizeof(struct sockaddr_in);
 447         udp_in[0].sin_family = AF_INET;
 448         udp_in[0].sin_port = uh->uh_sport;
 449         udp_in[0].sin_addr = ip->ip_src;
 450         udp_in[1].sin_len = sizeof(struct sockaddr_in);
 451         udp_in[1].sin_family = AF_INET;
 452         udp_in[1].sin_port = uh->uh_dport;
 453         udp_in[1].sin_addr = ip->ip_dst;
 454
 455         /*
 456          * Make mbuf data length reflect UDP length.  If not enough data to
 457          * reflect UDP length, drop.
 458          */
 459         len = ntohs((u_short)uh->uh_ulen);
 460         ip_len = ntohs(ip->ip_len) - iphlen;
 461         if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
 462                 /* Zero means checksum over the complete packet. */
 463                 if (len == 0)
 464                         len = ip_len;
 465                 cscov_partial = 0;
 466         }
 467         if (ip_len != len) {
 468                 if (len > ip_len || len < sizeof(struct udphdr)) {
 469                         UDPSTAT_INC(udps_badlen);
 470                         goto badunlocked;
 471                 }
 472                 if (proto == IPPROTO_UDP)
 473                         m_adj(m, len - ip_len);
 474         }
 475
 476         /*
 477          * Save a copy of the IP header in case we want restore it for
 478          * sending an ICMP error message in response.
 479          */
 480         if (!V_udp_blackhole)
 481                 save_ip = *ip;
 482         else
 483                 memset(&save_ip, 0, sizeof(save_ip));
 484
 485         /*
 486          * Checksum extended UDP header and data.
 487          */
 488         if (uh->uh_sum) {
 489                 u_short uh_sum;
 490
 491                 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
 492                     !cscov_partial) {
 493                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 494                                 uh_sum = m->m_pkthdr.csum_data;
 495                         else
 496                                 uh_sum = in_pseudo(ip->ip_src.s_addr,
 497                                     ip->ip_dst.s_addr, htonl((u_short)len +
 498                                     m->m_pkthdr.csum_data + proto));
 499                         uh_sum ^= 0xffff;
 500                 } else {
 501                         char b[9];
 502
 503                         bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
 504                         bzero(((struct ipovly *)ip)->ih_x1, 9);
 505                         ((struct ipovly *)ip)->ih_len = (proto == IPPROTO_UDP) ?
 506                             uh->uh_ulen : htons(ip_len);
 507                         uh_sum = in_cksum(m, len + sizeof (struct ip));
 508                         bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
 509                 }
 510                 if (uh_sum) {
 511                         UDPSTAT_INC(udps_badsum);
 512                         m_freem(m);
 513                         return (IPPROTO_DONE);
 514                 }
 515         } else {
 516                 if (proto == IPPROTO_UDP) {
 517                         UDPSTAT_INC(udps_nosum);
 518                 } else {
 519                         /* UDPLite requires a checksum */
 520                         /* XXX: What is the right UDPLite MIB counter here? */
 521                         m_freem(m);
 522                         return (IPPROTO_DONE);
 523                 }
 524         }
 525
 526         pcbinfo = udp_get_inpcbinfo(proto);
 527         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
 528             in_broadcast(ip->ip_dst, ifp)) {
 529                 struct inpcb *last;
 530                 struct inpcbhead *pcblist;
 531
 532                 INP_INFO_RLOCK_ET(pcbinfo, et);
 533                 pcblist = udp_get_pcblist(proto);
 534                 last = NULL;
 535                 CK_LIST_FOREACH(inp, pcblist, inp_list) {
 536                         if (inp->inp_lport != uh->uh_dport)
 537                                 continue;
 538 #ifdef INET6
 539                         if ((inp->inp_vflag & INP_IPV4) == 0)
 540                                 continue;
 541 #endif
 542                         if (inp->inp_laddr.s_addr != INADDR_ANY &&
 543                             inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
 544                                 continue;
 545                         if (inp->inp_faddr.s_addr != INADDR_ANY &&
 546                             inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 547                                 continue;
 548                         if (inp->inp_fport != 0 &&
 549                             inp->inp_fport != uh->uh_sport)
 550                                 continue;
 551
 552                         INP_RLOCK(inp);
 553
 554                         if (__predict_false(inp->inp_flags2 & INP_FREED)) {
 555                                 INP_RUNLOCK(inp);
 556                                 continue;
 557                         }
 558
 559                         /*
 560                          * XXXRW: Because we weren't holding either the inpcb
 561                          * or the hash lock when we checked for a match
 562                          * before, we should probably recheck now that the
 563                          * inpcb lock is held.
 564                          */
 565
 566                         /*
 567                          * Handle socket delivery policy for any-source
 568                          * and source-specific multicast. [RFC3678]
 569                          */
 570                         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 571                                 struct ip_moptions      *imo;
 572                                 struct sockaddr_in       group;
 573                                 int                      blocked;
 574
 575                                 imo = inp->inp_moptions;
 576                                 if (imo == NULL) {
 577                                         INP_RUNLOCK(inp);
 578                                         continue;
 579                                 }
 580                                 bzero(&group, sizeof(struct sockaddr_in));
 581                                 group.sin_len = sizeof(struct sockaddr_in);
 582                                 group.sin_family = AF_INET;
 583                                 group.sin_addr = ip->ip_dst;
 584
 585                                 blocked = imo_multi_filter(imo, ifp,
 586                                         (struct sockaddr *)&group,
 587                                         (struct sockaddr *)&udp_in[0]);
 588                                 if (blocked != MCAST_PASS) {
 589                                         if (blocked == MCAST_NOTGMEMBER)
 590                                                 IPSTAT_INC(ips_notmember);
 591                                         if (blocked == MCAST_NOTSMEMBER ||
 592                                             blocked == MCAST_MUTED)
 593                                                 UDPSTAT_INC(udps_filtermcast);
 594                                         INP_RUNLOCK(inp);
 595                                         continue;
 596                                 }
 597                         }
 598                         if (last != NULL) {
 599                                 struct mbuf *n;
 600
 601                                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) !=
 602                                     NULL) {
 603                                         if (proto == IPPROTO_UDPLITE)
 604                                                 UDPLITE_PROBE(receive, NULL, last, ip,
 605                                                     last, uh);
 606                                         else
 607                                                 UDP_PROBE(receive, NULL, last, ip, last,
 608                                                     uh);
 609                                         if (udp_append(last, ip, n, iphlen,
 610                                                 udp_in)) {
 611                                                 goto inp_lost;
 612                                         }
 613                                 }
 614                                 INP_RUNLOCK(last);
 615                         }
 616                         last = inp;
 617                         /*
 618                          * Don't look for additional matches if this one does
 619                          * not have either the SO_REUSEPORT or SO_REUSEADDR
 620                          * socket options set.  This heuristic avoids
 621                          * searching through all pcbs in the common case of a
 622                          * non-shared port.  It assumes that an application
 623                          * will never clear these options after setting them.
 624                          */
 625                         if ((last->inp_socket->so_options &
 626                             (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0)
 627                                 break;
 628                 }
 629
 630                 if (last == NULL) {
 631                         /*
 632                          * No matching pcb found; discard datagram.  (No need
 633                          * to send an ICMP Port Unreachable for a broadcast
 634                          * or multicast datgram.)
 635                          */
 636                         UDPSTAT_INC(udps_noportbcast);
 637                         if (inp)
 638                                 INP_RUNLOCK(inp);
 639                         INP_INFO_RUNLOCK_ET(pcbinfo, et);
 640                         goto badunlocked;
 641                 }
 642                 if (proto == IPPROTO_UDPLITE)
 643                         UDPLITE_PROBE(receive, NULL, last, ip, last, uh);
 644                 else
 645                         UDP_PROBE(receive, NULL, last, ip, last, uh);
 646                 if (udp_append(last, ip, m, iphlen, udp_in) == 0)
 647                         INP_RUNLOCK(last);
 648         inp_lost:
 649                 INP_INFO_RUNLOCK_ET(pcbinfo, et);
 650                 return (IPPROTO_DONE);
 651         }
 652
 653         /*
 654          * Locate pcb for datagram.
 655          */
 656
 657         /*
 658          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 659          */
 660         if ((m->m_flags & M_IP_NEXTHOP) &&
 661             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 662                 struct sockaddr_in *next_hop;
 663
 664                 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
 665
 666                 /*
 667                  * Transparently forwarded. Pretend to be the destination.
 668                  * Already got one like this?
 669                  */
 670                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 671                     ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
 672                 if (!inp) {
 673                         /*
 674                          * It's new.  Try to find the ambushing socket.
 675                          * Because we've rewritten the destination address,
 676                          * any hardware-generated hash is ignored.
 677                          */
 678                         inp = in_pcblookup(pcbinfo, ip->ip_src,
 679                             uh->uh_sport, next_hop->sin_addr,
 680                             next_hop->sin_port ? htons(next_hop->sin_port) :
 681                             uh->uh_dport, INPLOOKUP_WILDCARD |
 682                             INPLOOKUP_RLOCKPCB, ifp);
 683                 }
 684                 /* Remove the tag from the packet. We don't need it anymore. */
 685                 m_tag_delete(m, fwd_tag);
 686                 m->m_flags &= ~M_IP_NEXTHOP;
 687         } else
 688                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 689                     ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
 690                     INPLOOKUP_RLOCKPCB, ifp, m);
 691         if (inp == NULL) {
 692                 if (udp_log_in_vain) {
 693                         char src[INET_ADDRSTRLEN];
 694                         char dst[INET_ADDRSTRLEN];
 695
 696                         log(LOG_INFO,
 697                             "Connection attempt to UDP %s:%d from %s:%d\n",
 698                             inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
 699                             inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
 700                 }
 701                 if (proto == IPPROTO_UDPLITE)
 702                         UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
 703                 else
 704                         UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
 705                 UDPSTAT_INC(udps_noport);
 706                 if (m->m_flags & (M_BCAST | M_MCAST)) {
 707                         UDPSTAT_INC(udps_noportbcast);
 708                         goto badunlocked;
 709                 }
 710                 if (V_udp_blackhole)
 711                         goto badunlocked;
 712                 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
 713                         goto badunlocked;
 714                 *ip = save_ip;
 715                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
 716                 return (IPPROTO_DONE);
 717         }
 718
 719         /*
 720          * Check the minimum TTL for socket.
 721          */
 722         INP_RLOCK_ASSERT(inp);
 723         if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
 724                 if (proto == IPPROTO_UDPLITE)
 725                         UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 726                 else
 727                         UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 728                 INP_RUNLOCK(inp);
 729                 m_freem(m);
 730                 return (IPPROTO_DONE);
 731         }
 732         if (cscov_partial) {
 733                 struct udpcb *up;
 734
 735                 up = intoudpcb(inp);
 736                 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
 737                         INP_RUNLOCK(inp);
 738                         m_freem(m);
 739                         return (IPPROTO_DONE);
 740                 }
 741         }
 742
 743         if (proto == IPPROTO_UDPLITE)
 744                 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 745         else
 746                 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 747         if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
 748                 INP_RUNLOCK(inp);
 749         return (IPPROTO_DONE);
 750
 751 badunlocked:
 752         m_freem(m);
 753         return (IPPROTO_DONE);
 754 }
 755 #endif /* INET */
 756
 757 /*
 758  * Notify a udp user of an asynchronous error; just wake up so that they can
 759  * collect error status.
 760  */
 761 struct inpcb *
 762 udp_notify(struct inpcb *inp, int errno)
 763 {
 764
 765         INP_WLOCK_ASSERT(inp);
 766         if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
 767              errno == EHOSTDOWN) && inp->inp_route.ro_rt) {
 768                 RTFREE(inp->inp_route.ro_rt);
 769                 inp->inp_route.ro_rt = (struct rtentry *)NULL;
 770         }
 771
 772         inp->inp_socket->so_error = errno;
 773         sorwakeup(inp->inp_socket);
 774         sowwakeup(inp->inp_socket);
 775         return (inp);
 776 }
 777
 778 #ifdef INET
 779 static void
 780 udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip,
 781     struct inpcbinfo *pcbinfo)
 782 {
 783         struct ip *ip = vip;
 784         struct udphdr *uh;
 785         struct in_addr faddr;
 786         struct inpcb *inp;
 787
 788         faddr = ((struct sockaddr_in *)sa)->sin_addr;
 789         if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
 790                 return;
 791
 792         if (PRC_IS_REDIRECT(cmd)) {
 793                 /* signal EHOSTDOWN, as it flushes the cached route */
 794                 in_pcbnotifyall(&V_udbinfo, faddr, EHOSTDOWN, udp_notify);
 795                 return;
 796         }
 797
 798         /*
 799          * Hostdead is ugly because it goes linearly through all PCBs.
 800          *
 801          * XXX: We never get this from ICMP, otherwise it makes an excellent
 802          * DoS attack on machines with many connections.
 803          */
 804         if (cmd == PRC_HOSTDEAD)
 805                 ip = NULL;
 806         else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
 807                 return;
 808         if (ip != NULL) {
 809                 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 810                 inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 811                     ip->ip_src, uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
 812                 if (inp != NULL) {
 813                         INP_WLOCK_ASSERT(inp);
 814                         if (inp->inp_socket != NULL) {
 815                                 udp_notify(inp, inetctlerrmap[cmd]);
 816                         }
 817                         INP_WUNLOCK(inp);
 818                 } else {
 819                         inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 820                                            ip->ip_src, uh->uh_sport,
 821                                            INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 822                         if (inp != NULL) {
 823                                 struct udpcb *up;
 824                                 void *ctx;
 825                                 udp_tun_icmp_t func;
 826
 827                                 up = intoudpcb(inp);
 828                                 ctx = up->u_tun_ctx;
 829                                 func = up->u_icmp_func;
 830                                 INP_RUNLOCK(inp);
 831                                 if (func != NULL)
 832                                         (*func)(cmd, sa, vip, ctx);
 833                         }
 834                 }
 835         } else
 836                 in_pcbnotifyall(pcbinfo, faddr, inetctlerrmap[cmd],
 837                     udp_notify);
 838 }
 839 void
 840 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 841 {
 842
 843         return (udp_common_ctlinput(cmd, sa, vip, &V_udbinfo));
 844 }
 845
 846 void
 847 udplite_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 848 {
 849
 850         return (udp_common_ctlinput(cmd, sa, vip, &V_ulitecbinfo));
 851 }
 852 #endif /* INET */
 853
 854 static int
 855 udp_pcblist(SYSCTL_HANDLER_ARGS)
 856 {
 857         int error, i, n;
 858         struct inpcb *inp, **inp_list;
 859         inp_gen_t gencnt;
 860         struct xinpgen xig;
 861         struct epoch_tracker et;
 862
 863         /*
 864          * The process of preparing the PCB list is too time-consuming and
 865          * resource-intensive to repeat twice on every request.
 866          */
 867         if (req->oldptr == 0) {
 868                 n = V_udbinfo.ipi_count;
 869                 n += imax(n / 8, 10);
 870                 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
 871                 return (0);
 872         }
 873
 874         if (req->newptr != 0)
 875                 return (EPERM);
 876
 877         /*
 878          * OK, now we're committed to doing something.
 879          */
 880         INP_INFO_RLOCK_ET(&V_udbinfo, et);
 881         gencnt = V_udbinfo.ipi_gencnt;
 882         n = V_udbinfo.ipi_count;
 883         INP_INFO_RUNLOCK_ET(&V_udbinfo, et);
 884
 885         error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
 886                 + n * sizeof(struct xinpcb));
 887         if (error != 0)
 888                 return (error);
 889
 890         bzero(&xig, sizeof(xig));
 891         xig.xig_len = sizeof xig;
 892         xig.xig_count = n;
 893         xig.xig_gen = gencnt;
 894         xig.xig_sogen = so_gencnt;
 895         error = SYSCTL_OUT(req, &xig, sizeof xig);
 896         if (error)
 897                 return (error);
 898
 899         inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
 900         if (inp_list == NULL)
 901                 return (ENOMEM);
 902
 903         INP_INFO_RLOCK_ET(&V_udbinfo, et);
 904         for (inp = CK_LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n;
 905              inp = CK_LIST_NEXT(inp, inp_list)) {
 906                 INP_WLOCK(inp);
 907                 if (inp->inp_gencnt <= gencnt &&
 908                     cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
 909                         in_pcbref(inp);
 910                         inp_list[i++] = inp;
 911                 }
 912                 INP_WUNLOCK(inp);
 913         }
 914         INP_INFO_RUNLOCK_ET(&V_udbinfo, et);
 915         n = i;
 916
 917         error = 0;
 918         for (i = 0; i < n; i++) {
 919                 inp = inp_list[i];
 920                 INP_RLOCK(inp);
 921                 if (inp->inp_gencnt <= gencnt) {
 922                         struct xinpcb xi;
 923
 924                         in_pcbtoxinpcb(inp, &xi);
 925                         INP_RUNLOCK(inp);
 926                         error = SYSCTL_OUT(req, &xi, sizeof xi);
 927                 } else
 928                         INP_RUNLOCK(inp);
 929         }
 930         INP_INFO_WLOCK(&V_udbinfo);
 931         for (i = 0; i < n; i++) {
 932                 inp = inp_list[i];
 933                 INP_RLOCK(inp);
 934                 if (!in_pcbrele_rlocked(inp))
 935                         INP_RUNLOCK(inp);
 936         }
 937         INP_INFO_WUNLOCK(&V_udbinfo);
 938
 939         if (!error) {
 940                 /*
 941                  * Give the user an updated idea of our state.  If the
 942                  * generation differs from what we told her before, she knows
 943                  * that something happened while we were processing this
 944                  * request, and it might be necessary to retry.
 945                  */
 946                 INP_INFO_RLOCK_ET(&V_udbinfo, et);
 947                 xig.xig_gen = V_udbinfo.ipi_gencnt;
 948                 xig.xig_sogen = so_gencnt;
 949                 xig.xig_count = V_udbinfo.ipi_count;
 950                 INP_INFO_RUNLOCK_ET(&V_udbinfo, et);
 951                 error = SYSCTL_OUT(req, &xig, sizeof xig);
 952         }
 953         free(inp_list, M_TEMP);
 954         return (error);
 955 }
 956
 957 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
 958     CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
 959     udp_pcblist, "S,xinpcb", "List of active UDP sockets");
 960
 961 #ifdef INET
 962 static int
 963 udp_getcred(SYSCTL_HANDLER_ARGS)
 964 {
 965         struct xucred xuc;
 966         struct sockaddr_in addrs[2];
 967         struct inpcb *inp;
 968         int error;
 969
 970         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 971         if (error)
 972                 return (error);
 973         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 974         if (error)
 975                 return (error);
 976         inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
 977             addrs[0].sin_addr, addrs[0].sin_port,
 978             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 979         if (inp != NULL) {
 980                 INP_RLOCK_ASSERT(inp);
 981                 if (inp->inp_socket == NULL)
 982                         error = ENOENT;
 983                 if (error == 0)
 984                         error = cr_canseeinpcb(req->td->td_ucred, inp);
 985                 if (error == 0)
 986                         cru2x(inp->inp_cred, &xuc);
 987                 INP_RUNLOCK(inp);
 988         } else
 989                 error = ENOENT;
 990         if (error == 0)
 991                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 992         return (error);
 993 }
 994
 995 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
 996     CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
 997     udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
 998 #endif /* INET */
 999
1000 int
1001 udp_ctloutput(struct socket *so, struct sockopt *sopt)
1002 {
1003         struct inpcb *inp;
1004         struct udpcb *up;
1005         int isudplite, error, optval;
1006
1007         error = 0;
1008         isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
1009         inp = sotoinpcb(so);
1010         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1011         INP_WLOCK(inp);
1012         if (sopt->sopt_level != so->so_proto->pr_protocol) {
1013 #ifdef INET6
1014                 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
1015                         INP_WUNLOCK(inp);
1016                         error = ip6_ctloutput(so, sopt);
1017                 }
1018 #endif
1019 #if defined(INET) && defined(INET6)
1020                 else
1021 #endif
1022 #ifdef INET
1023                 {
1024                         INP_WUNLOCK(inp);
1025                         error = ip_ctloutput(so, sopt);
1026                 }
1027 #endif
1028                 return (error);
1029         }
1030
1031         switch (sopt->sopt_dir) {
1032         case SOPT_SET:
1033                 switch (sopt->sopt_name) {
1034 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1035 #ifdef INET
1036                 case UDP_ENCAP:
1037                         if (!IPSEC_ENABLED(ipv4)) {
1038                                 INP_WUNLOCK(inp);
1039                                 return (ENOPROTOOPT);
1040                         }
1041                         error = UDPENCAP_PCBCTL(inp, sopt);
1042                         break;
1043 #endif /* INET */
1044 #endif /* IPSEC */
1045                 case UDPLITE_SEND_CSCOV:
1046                 case UDPLITE_RECV_CSCOV:
1047                         if (!isudplite) {
1048                                 INP_WUNLOCK(inp);
1049                                 error = ENOPROTOOPT;
1050                                 break;
1051                         }
1052                         INP_WUNLOCK(inp);
1053                         error = sooptcopyin(sopt, &optval, sizeof(optval),
1054                             sizeof(optval));
1055                         if (error != 0)
1056                                 break;
1057                         inp = sotoinpcb(so);
1058                         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1059                         INP_WLOCK(inp);
1060                         up = intoudpcb(inp);
1061                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1062                         if ((optval != 0 && optval < 8) || (optval > 65535)) {
1063                                 INP_WUNLOCK(inp);
1064                                 error = EINVAL;
1065                                 break;
1066                         }
1067                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1068                                 up->u_txcslen = optval;
1069                         else
1070                                 up->u_rxcslen = optval;
1071                         INP_WUNLOCK(inp);
1072                         break;
1073                 default:
1074                         INP_WUNLOCK(inp);
1075                         error = ENOPROTOOPT;
1076                         break;
1077                 }
1078                 break;
1079         case SOPT_GET:
1080                 switch (sopt->sopt_name) {
1081 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1082 #ifdef INET
1083                 case UDP_ENCAP:
1084                         if (!IPSEC_ENABLED(ipv4)) {
1085                                 INP_WUNLOCK(inp);
1086                                 return (ENOPROTOOPT);
1087                         }
1088                         error = UDPENCAP_PCBCTL(inp, sopt);
1089                         break;
1090 #endif /* INET */
1091 #endif /* IPSEC */
1092                 case UDPLITE_SEND_CSCOV:
1093                 case UDPLITE_RECV_CSCOV:
1094                         if (!isudplite) {
1095                                 INP_WUNLOCK(inp);
1096                                 error = ENOPROTOOPT;
1097                                 break;
1098                         }
1099                         up = intoudpcb(inp);
1100                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1101                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1102                                 optval = up->u_txcslen;
1103                         else
1104                                 optval = up->u_rxcslen;
1105                         INP_WUNLOCK(inp);
1106                         error = sooptcopyout(sopt, &optval, sizeof(optval));
1107                         break;
1108                 default:
1109                         INP_WUNLOCK(inp);
1110                         error = ENOPROTOOPT;
1111                         break;
1112                 }
1113                 break;
1114         }
1115         return (error);
1116 }
1117
1118 #ifdef INET
1119 #define UH_WLOCKED      2
1120 #define UH_RLOCKED      1
1121 #define UH_UNLOCKED     0
1122 static int
1123 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
1124     struct mbuf *control, struct thread *td)
1125 {
1126         struct udpiphdr *ui;
1127         int len = m->m_pkthdr.len;
1128         struct in_addr faddr, laddr;
1129         struct cmsghdr *cm;
1130         struct inpcbinfo *pcbinfo;
1131         struct sockaddr_in *sin, src;
1132         struct epoch_tracker et;
1133         int cscov_partial = 0;
1134         int error = 0;
1135         int ipflags;
1136         u_short fport, lport;
1137         int unlock_udbinfo, unlock_inp;
1138         u_char tos;
1139         uint8_t pr;
1140         uint16_t cscov = 0;
1141         uint32_t flowid = 0;
1142         uint8_t flowtype = M_HASHTYPE_NONE;
1143
1144         /*
1145          * udp_output() may need to temporarily bind or connect the current
1146          * inpcb.  As such, we don't know up front whether we will need the
1147          * pcbinfo lock or not.  Do any work to decide what is needed up
1148          * front before acquiring any locks.
1149          */
1150         if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1151                 if (control)
1152                         m_freem(control);
1153                 m_freem(m);
1154                 return (EMSGSIZE);
1155         }
1156
1157         src.sin_family = 0;
1158         sin = (struct sockaddr_in *)addr;
1159 retry:
1160         if (sin == NULL ||
1161             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1162                 INP_WLOCK(inp);
1163                 /*
1164                  * In case we lost a race and another thread bound addr/port
1165                  * on the inp we cannot keep the wlock (which still would be
1166                  * fine) as further down, based on these values we make
1167                  * decisions for the pcbinfo lock.  If the locks are not in
1168                  * synch the assertions on unlock will fire, hence we go for
1169                  * one retry loop.
1170                  */
1171                 if (sin != NULL && (inp->inp_laddr.s_addr != INADDR_ANY ||
1172                     inp->inp_lport != 0)) {
1173                         INP_WUNLOCK(inp);
1174                         goto retry;
1175                 }
1176                 unlock_inp = UH_WLOCKED;
1177         } else {
1178                 INP_RLOCK(inp);
1179                 unlock_inp = UH_RLOCKED;
1180         }
1181         tos = inp->inp_ip_tos;
1182         if (control != NULL) {
1183                 /*
1184                  * XXX: Currently, we assume all the optional information is
1185                  * stored in a single mbuf.
1186                  */
1187                 if (control->m_next) {
1188                         if (unlock_inp == UH_WLOCKED)
1189                                 INP_WUNLOCK(inp);
1190                         else
1191                                 INP_RUNLOCK(inp);
1192                         m_freem(control);
1193                         m_freem(m);
1194                         return (EINVAL);
1195                 }
1196                 for (; control->m_len > 0;
1197                     control->m_data += CMSG_ALIGN(cm->cmsg_len),
1198                     control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1199                         cm = mtod(control, struct cmsghdr *);
1200                         if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1201                             || cm->cmsg_len > control->m_len) {
1202                                 error = EINVAL;
1203                                 break;
1204                         }
1205                         if (cm->cmsg_level != IPPROTO_IP)
1206                                 continue;
1207
1208                         switch (cm->cmsg_type) {
1209                         case IP_SENDSRCADDR:
1210                                 if (cm->cmsg_len !=
1211                                     CMSG_LEN(sizeof(struct in_addr))) {
1212                                         error = EINVAL;
1213                                         break;
1214                                 }
1215                                 bzero(&src, sizeof(src));
1216                                 src.sin_family = AF_INET;
1217                                 src.sin_len = sizeof(src);
1218                                 src.sin_port = inp->inp_lport;
1219                                 src.sin_addr =
1220                                     *(struct in_addr *)CMSG_DATA(cm);
1221                                 break;
1222
1223                         case IP_TOS:
1224                                 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1225                                         error = EINVAL;
1226                                         break;
1227                                 }
1228                                 tos = *(u_char *)CMSG_DATA(cm);
1229                                 break;
1230
1231                         case IP_FLOWID:
1232                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1233                                         error = EINVAL;
1234                                         break;
1235                                 }
1236                                 flowid = *(uint32_t *) CMSG_DATA(cm);
1237                                 break;
1238
1239                         case IP_FLOWTYPE:
1240                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1241                                         error = EINVAL;
1242                                         break;
1243                                 }
1244                                 flowtype = *(uint32_t *) CMSG_DATA(cm);
1245                                 break;
1246
1247 #ifdef  RSS
1248                         case IP_RSSBUCKETID:
1249                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1250                                         error = EINVAL;
1251                                         break;
1252                                 }
1253                                 /* This is just a placeholder for now */
1254                                 break;
1255 #endif  /* RSS */
1256                         default:
1257                                 error = ENOPROTOOPT;
1258                                 break;
1259                         }
1260                         if (error)
1261                                 break;
1262                 }
1263                 m_freem(control);
1264         }
1265         if (error) {
1266                 if (unlock_inp == UH_WLOCKED)
1267                         INP_WUNLOCK(inp);
1268                 else
1269                         INP_RUNLOCK(inp);
1270                 m_freem(m);
1271                 return (error);
1272         }
1273
1274         /*
1275          * In the old days, depending on whether or not the application had
1276          * bound or connected the socket, we had to do varying levels of work.
1277          * The optimal case was for a connected UDP socket, as a global lock
1278          * wasn't required at all.
1279          * In order to decide which we need, we required stability of the
1280          * inpcb binding, which we ensured by acquiring a read lock on the
1281          * inpcb.  This didn't strictly follow the lock order, so we played
1282          * the trylock and retry game.
1283          * With the re-introduction of the route-cache in some cases, we started
1284          * to acquire an early inp wlock and a possible race during re-lock
1285          * went away.  With the introduction of epoch(9) some read locking
1286          * became epoch(9) and the lock-order issues also went away.
1287          * Due to route-cache we may now hold more conservative locks than
1288          * otherwise required and have split up the 2nd case in case 2 and 3
1289          * in order to keep the udpinfo lock level in sync with the inp one
1290          * for the IP_SENDSRCADDR case below.
1291          */
1292         pr = inp->inp_socket->so_proto->pr_protocol;
1293         pcbinfo = udp_get_inpcbinfo(pr);
1294         if (sin != NULL &&
1295             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1296                 INP_HASH_WLOCK(pcbinfo);
1297                 unlock_udbinfo = UH_WLOCKED;
1298         } else if (sin != NULL &&
1299             (sin->sin_addr.s_addr == INADDR_ANY ||
1300             sin->sin_addr.s_addr == INADDR_BROADCAST ||
1301             inp->inp_laddr.s_addr == INADDR_ANY ||
1302             inp->inp_lport == 0)) {
1303                 INP_HASH_RLOCK_ET(pcbinfo, et);
1304                 unlock_udbinfo = UH_RLOCKED;
1305         } else if (src.sin_family == AF_INET) {
1306                 if (unlock_inp == UH_WLOCKED) {
1307                         INP_HASH_WLOCK(pcbinfo);
1308                         unlock_udbinfo = UH_WLOCKED;
1309                 } else {
1310                         INP_HASH_RLOCK_ET(pcbinfo, et);
1311                         unlock_udbinfo = UH_RLOCKED;
1312                 }
1313         } else
1314                 unlock_udbinfo = UH_UNLOCKED;
1315
1316         /*
1317          * If the IP_SENDSRCADDR control message was specified, override the
1318          * source address for this datagram.  Its use is invalidated if the
1319          * address thus specified is incomplete or clobbers other inpcbs.
1320          */
1321         laddr = inp->inp_laddr;
1322         lport = inp->inp_lport;
1323         if (src.sin_family == AF_INET) {
1324                 INP_HASH_LOCK_ASSERT(pcbinfo);
1325                 if ((lport == 0) ||
1326                     (laddr.s_addr == INADDR_ANY &&
1327                      src.sin_addr.s_addr == INADDR_ANY)) {
1328                         error = EINVAL;
1329                         goto release;
1330                 }
1331                 error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
1332                     &laddr.s_addr, &lport, td->td_ucred);
1333                 if (error)
1334                         goto release;
1335         }
1336
1337         /*
1338          * If a UDP socket has been connected, then a local address/port will
1339          * have been selected and bound.
1340          *
1341          * If a UDP socket has not been connected to, then an explicit
1342          * destination address must be used, in which case a local
1343          * address/port may not have been selected and bound.
1344          */
1345         if (sin != NULL) {
1346                 INP_LOCK_ASSERT(inp);
1347                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1348                         error = EISCONN;
1349                         goto release;
1350                 }
1351
1352                 /*
1353                  * Jail may rewrite the destination address, so let it do
1354                  * that before we use it.
1355                  */
1356                 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1357                 if (error)
1358                         goto release;
1359
1360                 /*
1361                  * If a local address or port hasn't yet been selected, or if
1362                  * the destination address needs to be rewritten due to using
1363                  * a special INADDR_ constant, invoke in_pcbconnect_setup()
1364                  * to do the heavy lifting.  Once a port is selected, we
1365                  * commit the binding back to the socket; we also commit the
1366                  * binding of the address if in jail.
1367                  *
1368                  * If we already have a valid binding and we're not
1369                  * requesting a destination address rewrite, use a fast path.
1370                  */
1371                 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1372                     inp->inp_lport == 0 ||
1373                     sin->sin_addr.s_addr == INADDR_ANY ||
1374                     sin->sin_addr.s_addr == INADDR_BROADCAST) {
1375                         INP_HASH_LOCK_ASSERT(pcbinfo);
1376                         error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
1377                             &lport, &faddr.s_addr, &fport, NULL,
1378                             td->td_ucred);
1379                         if (error)
1380                                 goto release;
1381
1382                         /*
1383                          * XXXRW: Why not commit the port if the address is
1384                          * !INADDR_ANY?
1385                          */
1386                         /* Commit the local port if newly assigned. */
1387                         if (inp->inp_laddr.s_addr == INADDR_ANY &&
1388                             inp->inp_lport == 0) {
1389                                 INP_WLOCK_ASSERT(inp);
1390                                 INP_HASH_WLOCK_ASSERT(pcbinfo);
1391                                 /*
1392                                  * Remember addr if jailed, to prevent
1393                                  * rebinding.
1394                                  */
1395                                 if (prison_flag(td->td_ucred, PR_IP4))
1396                                         inp->inp_laddr = laddr;
1397                                 inp->inp_lport = lport;
1398                                 if (in_pcbinshash(inp) != 0) {
1399                                         inp->inp_lport = 0;
1400                                         error = EAGAIN;
1401                                         goto release;
1402                                 }
1403                                 inp->inp_flags |= INP_ANONPORT;
1404                         }
1405                 } else {
1406                         faddr = sin->sin_addr;
1407                         fport = sin->sin_port;
1408                 }
1409         } else {
1410                 INP_LOCK_ASSERT(inp);
1411                 faddr = inp->inp_faddr;
1412                 fport = inp->inp_fport;
1413                 if (faddr.s_addr == INADDR_ANY) {
1414                         error = ENOTCONN;
1415                         goto release;
1416                 }
1417         }
1418
1419         /*
1420          * Calculate data length and get a mbuf for UDP, IP, and possible
1421          * link-layer headers.  Immediate slide the data pointer back forward
1422          * since we won't use that space at this layer.
1423          */
1424         M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1425         if (m == NULL) {
1426                 error = ENOBUFS;
1427                 goto release;
1428         }
1429         m->m_data += max_linkhdr;
1430         m->m_len -= max_linkhdr;
1431         m->m_pkthdr.len -= max_linkhdr;
1432
1433         /*
1434          * Fill in mbuf with extended UDP header and addresses and length put
1435          * into network format.
1436          */
1437         ui = mtod(m, struct udpiphdr *);
1438         bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1439         ui->ui_v = IPVERSION << 4;
1440         ui->ui_pr = pr;
1441         ui->ui_src = laddr;
1442         ui->ui_dst = faddr;
1443         ui->ui_sport = lport;
1444         ui->ui_dport = fport;
1445         ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1446         if (pr == IPPROTO_UDPLITE) {
1447                 struct udpcb *up;
1448                 uint16_t plen;
1449
1450                 up = intoudpcb(inp);
1451                 cscov = up->u_txcslen;
1452                 plen = (u_short)len + sizeof(struct udphdr);
1453                 if (cscov >= plen)
1454                         cscov = 0;
1455                 ui->ui_len = htons(plen);
1456                 ui->ui_ulen = htons(cscov);
1457                 /*
1458                  * For UDP-Lite, checksum coverage length of zero means
1459                  * the entire UDPLite packet is covered by the checksum.
1460                  */
1461                 cscov_partial = (cscov == 0) ? 0 : 1;
1462         }
1463
1464         /*
1465          * Set the Don't Fragment bit in the IP header.
1466          */
1467         if (inp->inp_flags & INP_DONTFRAG) {
1468                 struct ip *ip;
1469
1470                 ip = (struct ip *)&ui->ui_i;
1471                 ip->ip_off |= htons(IP_DF);
1472         }
1473
1474         ipflags = 0;
1475         if (inp->inp_socket->so_options & SO_DONTROUTE)
1476                 ipflags |= IP_ROUTETOIF;
1477         if (inp->inp_socket->so_options & SO_BROADCAST)
1478                 ipflags |= IP_ALLOWBROADCAST;
1479         if (inp->inp_flags & INP_ONESBCAST)
1480                 ipflags |= IP_SENDONES;
1481
1482 #ifdef MAC
1483         mac_inpcb_create_mbuf(inp, m);
1484 #endif
1485
1486         /*
1487          * Set up checksum and output datagram.
1488          */
1489         ui->ui_sum = 0;
1490         if (pr == IPPROTO_UDPLITE) {
1491                 if (inp->inp_flags & INP_ONESBCAST)
1492                         faddr.s_addr = INADDR_BROADCAST;
1493                 if (cscov_partial) {
1494                         if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1495                                 ui->ui_sum = 0xffff;
1496                 } else {
1497                         if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1498                                 ui->ui_sum = 0xffff;
1499                 }
1500         } else if (V_udp_cksum) {
1501                 if (inp->inp_flags & INP_ONESBCAST)
1502                         faddr.s_addr = INADDR_BROADCAST;
1503                 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1504                     htons((u_short)len + sizeof(struct udphdr) + pr));
1505                 m->m_pkthdr.csum_flags = CSUM_UDP;
1506                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1507         }
1508         ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1509         ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1510         ((struct ip *)ui)->ip_tos = tos;                /* XXX */
1511         UDPSTAT_INC(udps_opackets);
1512
1513         /*
1514          * Setup flowid / RSS information for outbound socket.
1515          *
1516          * Once the UDP code decides to set a flowid some other way,
1517          * this allows the flowid to be overridden by userland.
1518          */
1519         if (flowtype != M_HASHTYPE_NONE) {
1520                 m->m_pkthdr.flowid = flowid;
1521                 M_HASHTYPE_SET(m, flowtype);
1522         }
1523 #ifdef  RSS
1524         else {
1525                 uint32_t hash_val, hash_type;
1526                 /*
1527                  * Calculate an appropriate RSS hash for UDP and
1528                  * UDP Lite.
1529                  *
1530                  * The called function will take care of figuring out
1531                  * whether a 2-tuple or 4-tuple hash is required based
1532                  * on the currently configured scheme.
1533                  *
1534                  * Later later on connected socket values should be
1535                  * cached in the inpcb and reused, rather than constantly
1536                  * re-calculating it.
1537                  *
1538                  * UDP Lite is a different protocol number and will
1539                  * likely end up being hashed as a 2-tuple until
1540                  * RSS / NICs grow UDP Lite protocol awareness.
1541                  */
1542                 if (rss_proto_software_hash_v4(faddr, laddr, fport, lport,
1543                     pr, &hash_val, &hash_type) == 0) {
1544                         m->m_pkthdr.flowid = hash_val;
1545                         M_HASHTYPE_SET(m, hash_type);
1546                 }
1547         }
1548
1549         /*
1550          * Don't override with the inp cached flowid value.
1551          *
1552          * Depending upon the kind of send being done, the inp
1553          * flowid/flowtype values may actually not be appropriate
1554          * for this particular socket send.
1555          *
1556          * We should either leave the flowid at zero (which is what is
1557          * currently done) or set it to some software generated
1558          * hash value based on the packet contents.
1559          */
1560         ipflags |= IP_NODEFAULTFLOWID;
1561 #endif  /* RSS */
1562
1563         if (unlock_udbinfo == UH_WLOCKED)
1564                 INP_HASH_WUNLOCK(pcbinfo);
1565         else if (unlock_udbinfo == UH_RLOCKED)
1566                 INP_HASH_RUNLOCK_ET(pcbinfo, et);
1567         if (pr == IPPROTO_UDPLITE)
1568                 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1569         else
1570                 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1571         error = ip_output(m, inp->inp_options,
1572             (unlock_inp == UH_WLOCKED ? &inp->inp_route : NULL), ipflags,
1573             inp->inp_moptions, inp);
1574         if (unlock_inp == UH_WLOCKED)
1575                 INP_WUNLOCK(inp);
1576         else
1577                 INP_RUNLOCK(inp);
1578         return (error);
1579
1580 release:
1581         if (unlock_udbinfo == UH_WLOCKED) {
1582                 KASSERT(unlock_inp == UH_WLOCKED,
1583                     ("%s: excl udbinfo lock %#03x, shared inp lock %#03x, "
1584                     "sin %p daddr %#010x inp %p laddr %#010x lport %#06x "
1585                     "src fam %#04x",
1586                     __func__, unlock_udbinfo, unlock_inp, sin,
1587                     (sin != NULL) ? sin->sin_addr.s_addr : 0xfefefefe, inp,
1588                     inp->inp_laddr.s_addr, inp->inp_lport, src.sin_family));
1589                 INP_HASH_WUNLOCK(pcbinfo);
1590                 INP_WUNLOCK(inp);
1591         } else if (unlock_udbinfo == UH_RLOCKED) {
1592                 KASSERT(unlock_inp == UH_RLOCKED,
1593                     ("%s: shared udbinfo lock %#03x, excl inp lock %#03x, "
1594                     "sin %p daddr %#010x inp %p laddr %#010x lport %#06x "
1595                     "src fam %#04x",
1596                     __func__, unlock_udbinfo, unlock_inp, sin,
1597                     (sin != NULL) ? sin->sin_addr.s_addr : 0xfefefefe, inp,
1598                     inp->inp_laddr.s_addr, inp->inp_lport, src.sin_family));
1599                 INP_HASH_RUNLOCK_ET(pcbinfo, et);
1600                 INP_RUNLOCK(inp);
1601         } else if (unlock_inp == UH_WLOCKED)
1602                 INP_WUNLOCK(inp);
1603         else
1604                 INP_RUNLOCK(inp);
1605         m_freem(m);
1606         return (error);
1607 }
1608
1609 static void
1610 udp_abort(struct socket *so)
1611 {
1612         struct inpcb *inp;
1613         struct inpcbinfo *pcbinfo;
1614
1615         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1616         inp = sotoinpcb(so);
1617         KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1618         INP_WLOCK(inp);
1619         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1620                 INP_HASH_WLOCK(pcbinfo);
1621                 in_pcbdisconnect(inp);
1622                 inp->inp_laddr.s_addr = INADDR_ANY;
1623                 INP_HASH_WUNLOCK(pcbinfo);
1624                 soisdisconnected(so);
1625         }
1626         INP_WUNLOCK(inp);
1627 }
1628
1629 static int
1630 udp_attach(struct socket *so, int proto, struct thread *td)
1631 {
1632         static uint32_t udp_flowid;
1633         struct inpcb *inp;
1634         struct inpcbinfo *pcbinfo;
1635         int error;
1636
1637         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1638         inp = sotoinpcb(so);
1639         KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1640         error = soreserve(so, udp_sendspace, udp_recvspace);
1641         if (error)
1642                 return (error);
1643         INP_INFO_WLOCK(pcbinfo);
1644         error = in_pcballoc(so, pcbinfo);
1645         if (error) {
1646                 INP_INFO_WUNLOCK(pcbinfo);
1647                 return (error);
1648         }
1649
1650         inp = sotoinpcb(so);
1651         inp->inp_vflag |= INP_IPV4;
1652         inp->inp_ip_ttl = V_ip_defttl;
1653         inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1654         inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1655
1656         error = udp_newudpcb(inp);
1657         if (error) {
1658                 in_pcbdetach(inp);
1659                 in_pcbfree(inp);
1660                 INP_INFO_WUNLOCK(pcbinfo);
1661                 return (error);
1662         }
1663
1664         INP_WUNLOCK(inp);
1665         INP_INFO_WUNLOCK(pcbinfo);
1666         return (0);
1667 }
1668 #endif /* INET */
1669
1670 int
1671 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1672 {
1673         struct inpcb *inp;
1674         struct udpcb *up;
1675
1676         KASSERT(so->so_type == SOCK_DGRAM,
1677             ("udp_set_kernel_tunneling: !dgram"));
1678         inp = sotoinpcb(so);
1679         KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1680         INP_WLOCK(inp);
1681         up = intoudpcb(inp);
1682         if ((up->u_tun_func != NULL) ||
1683             (up->u_icmp_func != NULL)) {
1684                 INP_WUNLOCK(inp);
1685                 return (EBUSY);
1686         }
1687         up->u_tun_func = f;
1688         up->u_icmp_func = i;
1689         up->u_tun_ctx = ctx;
1690         INP_WUNLOCK(inp);
1691         return (0);
1692 }
1693
1694 #ifdef INET
1695 static int
1696 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1697 {
1698         struct inpcb *inp;
1699         struct inpcbinfo *pcbinfo;
1700         int error;
1701
1702         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1703         inp = sotoinpcb(so);
1704         KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1705         INP_WLOCK(inp);
1706         INP_HASH_WLOCK(pcbinfo);
1707         error = in_pcbbind(inp, nam, td->td_ucred);
1708         INP_HASH_WUNLOCK(pcbinfo);
1709         INP_WUNLOCK(inp);
1710         return (error);
1711 }
1712
1713 static void
1714 udp_close(struct socket *so)
1715 {
1716         struct inpcb *inp;
1717         struct inpcbinfo *pcbinfo;
1718
1719         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1720         inp = sotoinpcb(so);
1721         KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1722         INP_WLOCK(inp);
1723         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1724                 INP_HASH_WLOCK(pcbinfo);
1725                 in_pcbdisconnect(inp);
1726                 inp->inp_laddr.s_addr = INADDR_ANY;
1727                 INP_HASH_WUNLOCK(pcbinfo);
1728                 soisdisconnected(so);
1729         }
1730         INP_WUNLOCK(inp);
1731 }
1732
1733 static int
1734 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1735 {
1736         struct inpcb *inp;
1737         struct inpcbinfo *pcbinfo;
1738         struct sockaddr_in *sin;
1739         int error;
1740
1741         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1742         inp = sotoinpcb(so);
1743         KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1744         INP_WLOCK(inp);
1745         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1746                 INP_WUNLOCK(inp);
1747                 return (EISCONN);
1748         }
1749         sin = (struct sockaddr_in *)nam;
1750         error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1751         if (error != 0) {
1752                 INP_WUNLOCK(inp);
1753                 return (error);
1754         }
1755         INP_HASH_WLOCK(pcbinfo);
1756         error = in_pcbconnect(inp, nam, td->td_ucred);
1757         INP_HASH_WUNLOCK(pcbinfo);
1758         if (error == 0)
1759                 soisconnected(so);
1760         INP_WUNLOCK(inp);
1761         return (error);
1762 }
1763
1764 static void
1765 udp_detach(struct socket *so)
1766 {
1767         struct inpcb *inp;
1768         struct inpcbinfo *pcbinfo;
1769         struct udpcb *up;
1770
1771         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1772         inp = sotoinpcb(so);
1773         KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1774         KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1775             ("udp_detach: not disconnected"));
1776         INP_INFO_WLOCK(pcbinfo);
1777         INP_WLOCK(inp);
1778         up = intoudpcb(inp);
1779         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1780         inp->inp_ppcb = NULL;
1781         in_pcbdetach(inp);
1782         in_pcbfree(inp);
1783         INP_INFO_WUNLOCK(pcbinfo);
1784         udp_discardcb(up);
1785 }
1786
1787 static int
1788 udp_disconnect(struct socket *so)
1789 {
1790         struct inpcb *inp;
1791         struct inpcbinfo *pcbinfo;
1792
1793         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1794         inp = sotoinpcb(so);
1795         KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1796         INP_WLOCK(inp);
1797         if (inp->inp_faddr.s_addr == INADDR_ANY) {
1798                 INP_WUNLOCK(inp);
1799                 return (ENOTCONN);
1800         }
1801         INP_HASH_WLOCK(pcbinfo);
1802         in_pcbdisconnect(inp);
1803         inp->inp_laddr.s_addr = INADDR_ANY;
1804         INP_HASH_WUNLOCK(pcbinfo);
1805         SOCK_LOCK(so);
1806         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1807         SOCK_UNLOCK(so);
1808         INP_WUNLOCK(inp);
1809         return (0);
1810 }
1811
1812 static int
1813 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1814     struct mbuf *control, struct thread *td)
1815 {
1816         struct inpcb *inp;
1817
1818         inp = sotoinpcb(so);
1819         KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1820         return (udp_output(inp, m, addr, control, td));
1821 }
1822 #endif /* INET */
1823
1824 int
1825 udp_shutdown(struct socket *so)
1826 {
1827         struct inpcb *inp;
1828
1829         inp = sotoinpcb(so);
1830         KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1831         INP_WLOCK(inp);
1832         socantsendmore(so);
1833         INP_WUNLOCK(inp);
1834         return (0);
1835 }
1836
1837 #ifdef INET
1838 struct pr_usrreqs udp_usrreqs = {
1839         .pru_abort =            udp_abort,
1840         .pru_attach =           udp_attach,
1841         .pru_bind =             udp_bind,
1842         .pru_connect =          udp_connect,
1843         .pru_control =          in_control,
1844         .pru_detach =           udp_detach,
1845         .pru_disconnect =       udp_disconnect,
1846         .pru_peeraddr =         in_getpeeraddr,
1847         .pru_send =             udp_send,
1848         .pru_soreceive =        soreceive_dgram,
1849         .pru_sosend =           sosend_dgram,
1850         .pru_shutdown =         udp_shutdown,
1851         .pru_sockaddr =         in_getsockaddr,
1852         .pru_sosetlabel =       in_pcbsosetlabel,
1853         .pru_close =            udp_close,
1854 };
1855 #endif /* INET */