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 VNET_DEFINE(int, udp_log_in_vain) = 0;
 120 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW,
 121     &VNET_NAME(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         if (m->m_len < iphlen + sizeof(struct udphdr)) {
 425                 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
 426                         UDPSTAT_INC(udps_hdrops);
 427                         return (IPPROTO_DONE);
 428                 }
 429         }
 430         ip = mtod(m, struct ip *);
 431         uh = (struct udphdr *)((caddr_t)ip + iphlen);
 432         cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
 433
 434         /*
 435          * Destination port of 0 is illegal, based on RFC768.
 436          */
 437         if (uh->uh_dport == 0)
 438                 goto badunlocked;
 439
 440         /*
 441          * Construct sockaddr format source address.  Stuff source address
 442          * and datagram in user buffer.
 443          */
 444         bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
 445         udp_in[0].sin_len = sizeof(struct sockaddr_in);
 446         udp_in[0].sin_family = AF_INET;
 447         udp_in[0].sin_port = uh->uh_sport;
 448         udp_in[0].sin_addr = ip->ip_src;
 449         udp_in[1].sin_len = sizeof(struct sockaddr_in);
 450         udp_in[1].sin_family = AF_INET;
 451         udp_in[1].sin_port = uh->uh_dport;
 452         udp_in[1].sin_addr = ip->ip_dst;
 453
 454         /*
 455          * Make mbuf data length reflect UDP length.  If not enough data to
 456          * reflect UDP length, drop.
 457          */
 458         len = ntohs((u_short)uh->uh_ulen);
 459         ip_len = ntohs(ip->ip_len) - iphlen;
 460         if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
 461                 /* Zero means checksum over the complete packet. */
 462                 if (len == 0)
 463                         len = ip_len;
 464                 cscov_partial = 0;
 465         }
 466         if (ip_len != len) {
 467                 if (len > ip_len || len < sizeof(struct udphdr)) {
 468                         UDPSTAT_INC(udps_badlen);
 469                         goto badunlocked;
 470                 }
 471                 if (proto == IPPROTO_UDP)
 472                         m_adj(m, len - ip_len);
 473         }
 474
 475         /*
 476          * Save a copy of the IP header in case we want restore it for
 477          * sending an ICMP error message in response.
 478          */
 479         if (!V_udp_blackhole)
 480                 save_ip = *ip;
 481         else
 482                 memset(&save_ip, 0, sizeof(save_ip));
 483
 484         /*
 485          * Checksum extended UDP header and data.
 486          */
 487         if (uh->uh_sum) {
 488                 u_short uh_sum;
 489
 490                 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
 491                     !cscov_partial) {
 492                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 493                                 uh_sum = m->m_pkthdr.csum_data;
 494                         else
 495                                 uh_sum = in_pseudo(ip->ip_src.s_addr,
 496                                     ip->ip_dst.s_addr, htonl((u_short)len +
 497                                     m->m_pkthdr.csum_data + proto));
 498                         uh_sum ^= 0xffff;
 499                 } else {
 500                         char b[9];
 501
 502                         bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
 503                         bzero(((struct ipovly *)ip)->ih_x1, 9);
 504                         ((struct ipovly *)ip)->ih_len = (proto == IPPROTO_UDP) ?
 505                             uh->uh_ulen : htons(ip_len);
 506                         uh_sum = in_cksum(m, len + sizeof (struct ip));
 507                         bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
 508                 }
 509                 if (uh_sum) {
 510                         UDPSTAT_INC(udps_badsum);
 511                         m_freem(m);
 512                         return (IPPROTO_DONE);
 513                 }
 514         } else {
 515                 if (proto == IPPROTO_UDP) {
 516                         UDPSTAT_INC(udps_nosum);
 517                 } else {
 518                         /* UDPLite requires a checksum */
 519                         /* XXX: What is the right UDPLite MIB counter here? */
 520                         m_freem(m);
 521                         return (IPPROTO_DONE);
 522                 }
 523         }
 524
 525         pcbinfo = udp_get_inpcbinfo(proto);
 526         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
 527             in_broadcast(ip->ip_dst, ifp)) {
 528                 struct inpcb *last;
 529                 struct inpcbhead *pcblist;
 530
 531                 INP_INFO_RLOCK_ET(pcbinfo, et);
 532                 pcblist = udp_get_pcblist(proto);
 533                 last = NULL;
 534                 CK_LIST_FOREACH(inp, pcblist, inp_list) {
 535                         if (inp->inp_lport != uh->uh_dport)
 536                                 continue;
 537 #ifdef INET6
 538                         if ((inp->inp_vflag & INP_IPV4) == 0)
 539                                 continue;
 540 #endif
 541                         if (inp->inp_laddr.s_addr != INADDR_ANY &&
 542                             inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
 543                                 continue;
 544                         if (inp->inp_faddr.s_addr != INADDR_ANY &&
 545                             inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 546                                 continue;
 547                         if (inp->inp_fport != 0 &&
 548                             inp->inp_fport != uh->uh_sport)
 549                                 continue;
 550
 551                         INP_RLOCK(inp);
 552
 553                         if (__predict_false(inp->inp_flags2 & INP_FREED)) {
 554                                 INP_RUNLOCK(inp);
 555                                 continue;
 556                         }
 557
 558                         /*
 559                          * XXXRW: Because we weren't holding either the inpcb
 560                          * or the hash lock when we checked for a match
 561                          * before, we should probably recheck now that the
 562                          * inpcb lock is held.
 563                          */
 564
 565                         /*
 566                          * Handle socket delivery policy for any-source
 567                          * and source-specific multicast. [RFC3678]
 568                          */
 569                         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 570                                 struct ip_moptions      *imo;
 571                                 struct sockaddr_in       group;
 572                                 int                      blocked;
 573
 574                                 imo = inp->inp_moptions;
 575                                 if (imo == NULL) {
 576                                         INP_RUNLOCK(inp);
 577                                         continue;
 578                                 }
 579                                 bzero(&group, sizeof(struct sockaddr_in));
 580                                 group.sin_len = sizeof(struct sockaddr_in);
 581                                 group.sin_family = AF_INET;
 582                                 group.sin_addr = ip->ip_dst;
 583
 584                                 blocked = imo_multi_filter(imo, ifp,
 585                                         (struct sockaddr *)&group,
 586                                         (struct sockaddr *)&udp_in[0]);
 587                                 if (blocked != MCAST_PASS) {
 588                                         if (blocked == MCAST_NOTGMEMBER)
 589                                                 IPSTAT_INC(ips_notmember);
 590                                         if (blocked == MCAST_NOTSMEMBER ||
 591                                             blocked == MCAST_MUTED)
 592                                                 UDPSTAT_INC(udps_filtermcast);
 593                                         INP_RUNLOCK(inp);
 594                                         continue;
 595                                 }
 596                         }
 597                         if (last != NULL) {
 598                                 struct mbuf *n;
 599
 600                                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) !=
 601                                     NULL) {
 602                                         if (proto == IPPROTO_UDPLITE)
 603                                                 UDPLITE_PROBE(receive, NULL, last, ip,
 604                                                     last, uh);
 605                                         else
 606                                                 UDP_PROBE(receive, NULL, last, ip, last,
 607                                                     uh);
 608                                         if (udp_append(last, ip, n, iphlen,
 609                                                 udp_in)) {
 610                                                 goto inp_lost;
 611                                         }
 612                                 }
 613                                 INP_RUNLOCK(last);
 614                         }
 615                         last = inp;
 616                         /*
 617                          * Don't look for additional matches if this one does
 618                          * not have either the SO_REUSEPORT or SO_REUSEADDR
 619                          * socket options set.  This heuristic avoids
 620                          * searching through all pcbs in the common case of a
 621                          * non-shared port.  It assumes that an application
 622                          * will never clear these options after setting them.
 623                          */
 624                         if ((last->inp_socket->so_options &
 625                             (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0)
 626                                 break;
 627                 }
 628
 629                 if (last == NULL) {
 630                         /*
 631                          * No matching pcb found; discard datagram.  (No need
 632                          * to send an ICMP Port Unreachable for a broadcast
 633                          * or multicast datgram.)
 634                          */
 635                         UDPSTAT_INC(udps_noportbcast);
 636                         if (inp)
 637                                 INP_RUNLOCK(inp);
 638                         INP_INFO_RUNLOCK_ET(pcbinfo, et);
 639                         goto badunlocked;
 640                 }
 641                 if (proto == IPPROTO_UDPLITE)
 642                         UDPLITE_PROBE(receive, NULL, last, ip, last, uh);
 643                 else
 644                         UDP_PROBE(receive, NULL, last, ip, last, uh);
 645                 if (udp_append(last, ip, m, iphlen, udp_in) == 0)
 646                         INP_RUNLOCK(last);
 647         inp_lost:
 648                 INP_INFO_RUNLOCK_ET(pcbinfo, et);
 649                 return (IPPROTO_DONE);
 650         }
 651
 652         /*
 653          * Locate pcb for datagram.
 654          */
 655
 656         /*
 657          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 658          */
 659         if ((m->m_flags & M_IP_NEXTHOP) &&
 660             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 661                 struct sockaddr_in *next_hop;
 662
 663                 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
 664
 665                 /*
 666                  * Transparently forwarded. Pretend to be the destination.
 667                  * Already got one like this?
 668                  */
 669                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 670                     ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
 671                 if (!inp) {
 672                         /*
 673                          * It's new.  Try to find the ambushing socket.
 674                          * Because we've rewritten the destination address,
 675                          * any hardware-generated hash is ignored.
 676                          */
 677                         inp = in_pcblookup(pcbinfo, ip->ip_src,
 678                             uh->uh_sport, next_hop->sin_addr,
 679                             next_hop->sin_port ? htons(next_hop->sin_port) :
 680                             uh->uh_dport, INPLOOKUP_WILDCARD |
 681                             INPLOOKUP_RLOCKPCB, ifp);
 682                 }
 683                 /* Remove the tag from the packet. We don't need it anymore. */
 684                 m_tag_delete(m, fwd_tag);
 685                 m->m_flags &= ~M_IP_NEXTHOP;
 686         } else
 687                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 688                     ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
 689                     INPLOOKUP_RLOCKPCB, ifp, m);
 690         if (inp == NULL) {
 691                 if (V_udp_log_in_vain) {
 692                         char src[INET_ADDRSTRLEN];
 693                         char dst[INET_ADDRSTRLEN];
 694
 695                         log(LOG_INFO,
 696                             "Connection attempt to UDP %s:%d from %s:%d\n",
 697                             inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
 698                             inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
 699                 }
 700                 if (proto == IPPROTO_UDPLITE)
 701                         UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
 702                 else
 703                         UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
 704                 UDPSTAT_INC(udps_noport);
 705                 if (m->m_flags & (M_BCAST | M_MCAST)) {
 706                         UDPSTAT_INC(udps_noportbcast);
 707                         goto badunlocked;
 708                 }
 709                 if (V_udp_blackhole)
 710                         goto badunlocked;
 711                 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
 712                         goto badunlocked;
 713                 *ip = save_ip;
 714                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
 715                 return (IPPROTO_DONE);
 716         }
 717
 718         /*
 719          * Check the minimum TTL for socket.
 720          */
 721         INP_RLOCK_ASSERT(inp);
 722         if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
 723                 if (proto == IPPROTO_UDPLITE)
 724                         UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 725                 else
 726                         UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 727                 INP_RUNLOCK(inp);
 728                 m_freem(m);
 729                 return (IPPROTO_DONE);
 730         }
 731         if (cscov_partial) {
 732                 struct udpcb *up;
 733
 734                 up = intoudpcb(inp);
 735                 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
 736                         INP_RUNLOCK(inp);
 737                         m_freem(m);
 738                         return (IPPROTO_DONE);
 739                 }
 740         }
 741
 742         if (proto == IPPROTO_UDPLITE)
 743                 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 744         else
 745                 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 746         if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
 747                 INP_RUNLOCK(inp);
 748         return (IPPROTO_DONE);
 749
 750 badunlocked:
 751         m_freem(m);
 752         return (IPPROTO_DONE);
 753 }
 754 #endif /* INET */
 755
 756 /*
 757  * Notify a udp user of an asynchronous error; just wake up so that they can
 758  * collect error status.
 759  */
 760 struct inpcb *
 761 udp_notify(struct inpcb *inp, int errno)
 762 {
 763
 764         INP_WLOCK_ASSERT(inp);
 765         if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
 766              errno == EHOSTDOWN) && inp->inp_route.ro_rt) {
 767                 RTFREE(inp->inp_route.ro_rt);
 768                 inp->inp_route.ro_rt = (struct rtentry *)NULL;
 769         }
 770
 771         inp->inp_socket->so_error = errno;
 772         sorwakeup(inp->inp_socket);
 773         sowwakeup(inp->inp_socket);
 774         return (inp);
 775 }
 776
 777 #ifdef INET
 778 static void
 779 udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip,
 780     struct inpcbinfo *pcbinfo)
 781 {
 782         struct ip *ip = vip;
 783         struct udphdr *uh;
 784         struct in_addr faddr;
 785         struct inpcb *inp;
 786
 787         faddr = ((struct sockaddr_in *)sa)->sin_addr;
 788         if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
 789                 return;
 790
 791         if (PRC_IS_REDIRECT(cmd)) {
 792                 /* signal EHOSTDOWN, as it flushes the cached route */
 793                 in_pcbnotifyall(&V_udbinfo, faddr, EHOSTDOWN, udp_notify);
 794                 return;
 795         }
 796
 797         /*
 798          * Hostdead is ugly because it goes linearly through all PCBs.
 799          *
 800          * XXX: We never get this from ICMP, otherwise it makes an excellent
 801          * DoS attack on machines with many connections.
 802          */
 803         if (cmd == PRC_HOSTDEAD)
 804                 ip = NULL;
 805         else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
 806                 return;
 807         if (ip != NULL) {
 808                 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 809                 inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 810                     ip->ip_src, uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
 811                 if (inp != NULL) {
 812                         INP_WLOCK_ASSERT(inp);
 813                         if (inp->inp_socket != NULL) {
 814                                 udp_notify(inp, inetctlerrmap[cmd]);
 815                         }
 816                         INP_WUNLOCK(inp);
 817                 } else {
 818                         inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 819                                            ip->ip_src, uh->uh_sport,
 820                                            INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 821                         if (inp != NULL) {
 822                                 struct udpcb *up;
 823                                 void *ctx;
 824                                 udp_tun_icmp_t func;
 825
 826                                 up = intoudpcb(inp);
 827                                 ctx = up->u_tun_ctx;
 828                                 func = up->u_icmp_func;
 829                                 INP_RUNLOCK(inp);
 830                                 if (func != NULL)
 831                                         (*func)(cmd, sa, vip, ctx);
 832                         }
 833                 }
 834         } else
 835                 in_pcbnotifyall(pcbinfo, faddr, inetctlerrmap[cmd],
 836                     udp_notify);
 837 }
 838 void
 839 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 840 {
 841
 842         return (udp_common_ctlinput(cmd, sa, vip, &V_udbinfo));
 843 }
 844
 845 void
 846 udplite_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 847 {
 848
 849         return (udp_common_ctlinput(cmd, sa, vip, &V_ulitecbinfo));
 850 }
 851 #endif /* INET */
 852
 853 static int
 854 udp_pcblist(SYSCTL_HANDLER_ARGS)
 855 {
 856         int error, i, n;
 857         struct inpcb *inp, **inp_list;
 858         inp_gen_t gencnt;
 859         struct xinpgen xig;
 860         struct epoch_tracker et;
 861
 862         /*
 863          * The process of preparing the PCB list is too time-consuming and
 864          * resource-intensive to repeat twice on every request.
 865          */
 866         if (req->oldptr == 0) {
 867                 n = V_udbinfo.ipi_count;
 868                 n += imax(n / 8, 10);
 869                 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
 870                 return (0);
 871         }
 872
 873         if (req->newptr != 0)
 874                 return (EPERM);
 875
 876         /*
 877          * OK, now we're committed to doing something.
 878          */
 879         INP_INFO_RLOCK_ET(&V_udbinfo, et);
 880         gencnt = V_udbinfo.ipi_gencnt;
 881         n = V_udbinfo.ipi_count;
 882         INP_INFO_RUNLOCK_ET(&V_udbinfo, et);
 883
 884         error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
 885                 + n * sizeof(struct xinpcb));
 886         if (error != 0)
 887                 return (error);
 888
 889         bzero(&xig, sizeof(xig));
 890         xig.xig_len = sizeof xig;
 891         xig.xig_count = n;
 892         xig.xig_gen = gencnt;
 893         xig.xig_sogen = so_gencnt;
 894         error = SYSCTL_OUT(req, &xig, sizeof xig);
 895         if (error)
 896                 return (error);
 897
 898         inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
 899         if (inp_list == NULL)
 900                 return (ENOMEM);
 901
 902         INP_INFO_RLOCK_ET(&V_udbinfo, et);
 903         for (inp = CK_LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n;
 904              inp = CK_LIST_NEXT(inp, inp_list)) {
 905                 INP_WLOCK(inp);
 906                 if (inp->inp_gencnt <= gencnt &&
 907                     cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
 908                         in_pcbref(inp);
 909                         inp_list[i++] = inp;
 910                 }
 911                 INP_WUNLOCK(inp);
 912         }
 913         INP_INFO_RUNLOCK_ET(&V_udbinfo, et);
 914         n = i;
 915
 916         error = 0;
 917         for (i = 0; i < n; i++) {
 918                 inp = inp_list[i];
 919                 INP_RLOCK(inp);
 920                 if (inp->inp_gencnt <= gencnt) {
 921                         struct xinpcb xi;
 922
 923                         in_pcbtoxinpcb(inp, &xi);
 924                         INP_RUNLOCK(inp);
 925                         error = SYSCTL_OUT(req, &xi, sizeof xi);
 926                 } else
 927                         INP_RUNLOCK(inp);
 928         }
 929         INP_INFO_WLOCK(&V_udbinfo);
 930         for (i = 0; i < n; i++) {
 931                 inp = inp_list[i];
 932                 INP_RLOCK(inp);
 933                 if (!in_pcbrele_rlocked(inp))
 934                         INP_RUNLOCK(inp);
 935         }
 936         INP_INFO_WUNLOCK(&V_udbinfo);
 937
 938         if (!error) {
 939                 /*
 940                  * Give the user an updated idea of our state.  If the
 941                  * generation differs from what we told her before, she knows
 942                  * that something happened while we were processing this
 943                  * request, and it might be necessary to retry.
 944                  */
 945                 INP_INFO_RLOCK_ET(&V_udbinfo, et);
 946                 xig.xig_gen = V_udbinfo.ipi_gencnt;
 947                 xig.xig_sogen = so_gencnt;
 948                 xig.xig_count = V_udbinfo.ipi_count;
 949                 INP_INFO_RUNLOCK_ET(&V_udbinfo, et);
 950                 error = SYSCTL_OUT(req, &xig, sizeof xig);
 951         }
 952         free(inp_list, M_TEMP);
 953         return (error);
 954 }
 955
 956 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
 957     CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
 958     udp_pcblist, "S,xinpcb", "List of active UDP sockets");
 959
 960 #ifdef INET
 961 static int
 962 udp_getcred(SYSCTL_HANDLER_ARGS)
 963 {
 964         struct xucred xuc;
 965         struct sockaddr_in addrs[2];
 966         struct inpcb *inp;
 967         int error;
 968
 969         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 970         if (error)
 971                 return (error);
 972         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 973         if (error)
 974                 return (error);
 975         inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
 976             addrs[0].sin_addr, addrs[0].sin_port,
 977             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 978         if (inp != NULL) {
 979                 INP_RLOCK_ASSERT(inp);
 980                 if (inp->inp_socket == NULL)
 981                         error = ENOENT;
 982                 if (error == 0)
 983                         error = cr_canseeinpcb(req->td->td_ucred, inp);
 984                 if (error == 0)
 985                         cru2x(inp->inp_cred, &xuc);
 986                 INP_RUNLOCK(inp);
 987         } else
 988                 error = ENOENT;
 989         if (error == 0)
 990                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 991         return (error);
 992 }
 993
 994 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
 995     CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
 996     udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
 997 #endif /* INET */
 998
 999 int
1000 udp_ctloutput(struct socket *so, struct sockopt *sopt)
1001 {
1002         struct inpcb *inp;
1003         struct udpcb *up;
1004         int isudplite, error, optval;
1005
1006         error = 0;
1007         isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
1008         inp = sotoinpcb(so);
1009         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1010         INP_WLOCK(inp);
1011         if (sopt->sopt_level != so->so_proto->pr_protocol) {
1012 #ifdef INET6
1013                 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
1014                         INP_WUNLOCK(inp);
1015                         error = ip6_ctloutput(so, sopt);
1016                 }
1017 #endif
1018 #if defined(INET) && defined(INET6)
1019                 else
1020 #endif
1021 #ifdef INET
1022                 {
1023                         INP_WUNLOCK(inp);
1024                         error = ip_ctloutput(so, sopt);
1025                 }
1026 #endif
1027                 return (error);
1028         }
1029
1030         switch (sopt->sopt_dir) {
1031         case SOPT_SET:
1032                 switch (sopt->sopt_name) {
1033 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1034 #ifdef INET
1035                 case UDP_ENCAP:
1036                         if (!IPSEC_ENABLED(ipv4)) {
1037                                 INP_WUNLOCK(inp);
1038                                 return (ENOPROTOOPT);
1039                         }
1040                         error = UDPENCAP_PCBCTL(inp, sopt);
1041                         break;
1042 #endif /* INET */
1043 #endif /* IPSEC */
1044                 case UDPLITE_SEND_CSCOV:
1045                 case UDPLITE_RECV_CSCOV:
1046                         if (!isudplite) {
1047                                 INP_WUNLOCK(inp);
1048                                 error = ENOPROTOOPT;
1049                                 break;
1050                         }
1051                         INP_WUNLOCK(inp);
1052                         error = sooptcopyin(sopt, &optval, sizeof(optval),
1053                             sizeof(optval));
1054                         if (error != 0)
1055                                 break;
1056                         inp = sotoinpcb(so);
1057                         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1058                         INP_WLOCK(inp);
1059                         up = intoudpcb(inp);
1060                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1061                         if ((optval != 0 && optval < 8) || (optval > 65535)) {
1062                                 INP_WUNLOCK(inp);
1063                                 error = EINVAL;
1064                                 break;
1065                         }
1066                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1067                                 up->u_txcslen = optval;
1068                         else
1069                                 up->u_rxcslen = optval;
1070                         INP_WUNLOCK(inp);
1071                         break;
1072                 default:
1073                         INP_WUNLOCK(inp);
1074                         error = ENOPROTOOPT;
1075                         break;
1076                 }
1077                 break;
1078         case SOPT_GET:
1079                 switch (sopt->sopt_name) {
1080 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1081 #ifdef INET
1082                 case UDP_ENCAP:
1083                         if (!IPSEC_ENABLED(ipv4)) {
1084                                 INP_WUNLOCK(inp);
1085                                 return (ENOPROTOOPT);
1086                         }
1087                         error = UDPENCAP_PCBCTL(inp, sopt);
1088                         break;
1089 #endif /* INET */
1090 #endif /* IPSEC */
1091                 case UDPLITE_SEND_CSCOV:
1092                 case UDPLITE_RECV_CSCOV:
1093                         if (!isudplite) {
1094                                 INP_WUNLOCK(inp);
1095                                 error = ENOPROTOOPT;
1096                                 break;
1097                         }
1098                         up = intoudpcb(inp);
1099                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1100                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1101                                 optval = up->u_txcslen;
1102                         else
1103                                 optval = up->u_rxcslen;
1104                         INP_WUNLOCK(inp);
1105                         error = sooptcopyout(sopt, &optval, sizeof(optval));
1106                         break;
1107                 default:
1108                         INP_WUNLOCK(inp);
1109                         error = ENOPROTOOPT;
1110                         break;
1111                 }
1112                 break;
1113         }
1114         return (error);
1115 }
1116
1117 #ifdef INET
1118 #define UH_WLOCKED      2
1119 #define UH_RLOCKED      1
1120 #define UH_UNLOCKED     0
1121 static int
1122 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
1123     struct mbuf *control, struct thread *td)
1124 {
1125         struct udpiphdr *ui;
1126         int len = m->m_pkthdr.len;
1127         struct in_addr faddr, laddr;
1128         struct cmsghdr *cm;
1129         struct inpcbinfo *pcbinfo;
1130         struct sockaddr_in *sin, src;
1131         struct epoch_tracker et;
1132         int cscov_partial = 0;
1133         int error = 0;
1134         int ipflags;
1135         u_short fport, lport;
1136         int unlock_udbinfo, unlock_inp;
1137         u_char tos;
1138         uint8_t pr;
1139         uint16_t cscov = 0;
1140         uint32_t flowid = 0;
1141         uint8_t flowtype = M_HASHTYPE_NONE;
1142
1143         /*
1144          * udp_output() may need to temporarily bind or connect the current
1145          * inpcb.  As such, we don't know up front whether we will need the
1146          * pcbinfo lock or not.  Do any work to decide what is needed up
1147          * front before acquiring any locks.
1148          */
1149         if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1150                 if (control)
1151                         m_freem(control);
1152                 m_freem(m);
1153                 return (EMSGSIZE);
1154         }
1155
1156         src.sin_family = 0;
1157         sin = (struct sockaddr_in *)addr;
1158 retry:
1159         if (sin == NULL ||
1160             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1161                 INP_WLOCK(inp);
1162                 /*
1163                  * In case we lost a race and another thread bound addr/port
1164                  * on the inp we cannot keep the wlock (which still would be
1165                  * fine) as further down, based on these values we make
1166                  * decisions for the pcbinfo lock.  If the locks are not in
1167                  * synch the assertions on unlock will fire, hence we go for
1168                  * one retry loop.
1169                  */
1170                 if (sin != NULL && (inp->inp_laddr.s_addr != INADDR_ANY ||
1171                     inp->inp_lport != 0)) {
1172                         INP_WUNLOCK(inp);
1173                         goto retry;
1174                 }
1175                 unlock_inp = UH_WLOCKED;
1176         } else {
1177                 INP_RLOCK(inp);
1178                 unlock_inp = UH_RLOCKED;
1179         }
1180         tos = inp->inp_ip_tos;
1181         if (control != NULL) {
1182                 /*
1183                  * XXX: Currently, we assume all the optional information is
1184                  * stored in a single mbuf.
1185                  */
1186                 if (control->m_next) {
1187                         if (unlock_inp == UH_WLOCKED)
1188                                 INP_WUNLOCK(inp);
1189                         else
1190                                 INP_RUNLOCK(inp);
1191                         m_freem(control);
1192                         m_freem(m);
1193                         return (EINVAL);
1194                 }
1195                 for (; control->m_len > 0;
1196                     control->m_data += CMSG_ALIGN(cm->cmsg_len),
1197                     control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1198                         cm = mtod(control, struct cmsghdr *);
1199                         if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1200                             || cm->cmsg_len > control->m_len) {
1201                                 error = EINVAL;
1202                                 break;
1203                         }
1204                         if (cm->cmsg_level != IPPROTO_IP)
1205                                 continue;
1206
1207                         switch (cm->cmsg_type) {
1208                         case IP_SENDSRCADDR:
1209                                 if (cm->cmsg_len !=
1210                                     CMSG_LEN(sizeof(struct in_addr))) {
1211                                         error = EINVAL;
1212                                         break;
1213                                 }
1214                                 bzero(&src, sizeof(src));
1215                                 src.sin_family = AF_INET;
1216                                 src.sin_len = sizeof(src);
1217                                 src.sin_port = inp->inp_lport;
1218                                 src.sin_addr =
1219                                     *(struct in_addr *)CMSG_DATA(cm);
1220                                 break;
1221
1222                         case IP_TOS:
1223                                 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1224                                         error = EINVAL;
1225                                         break;
1226                                 }
1227                                 tos = *(u_char *)CMSG_DATA(cm);
1228                                 break;
1229
1230                         case IP_FLOWID:
1231                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1232                                         error = EINVAL;
1233                                         break;
1234                                 }
1235                                 flowid = *(uint32_t *) CMSG_DATA(cm);
1236                                 break;
1237
1238                         case IP_FLOWTYPE:
1239                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1240                                         error = EINVAL;
1241                                         break;
1242                                 }
1243                                 flowtype = *(uint32_t *) CMSG_DATA(cm);
1244                                 break;
1245
1246 #ifdef  RSS
1247                         case IP_RSSBUCKETID:
1248                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1249                                         error = EINVAL;
1250                                         break;
1251                                 }
1252                                 /* This is just a placeholder for now */
1253                                 break;
1254 #endif  /* RSS */
1255                         default:
1256                                 error = ENOPROTOOPT;
1257                                 break;
1258                         }
1259                         if (error)
1260                                 break;
1261                 }
1262                 m_freem(control);
1263         }
1264         if (error) {
1265                 if (unlock_inp == UH_WLOCKED)
1266                         INP_WUNLOCK(inp);
1267                 else
1268                         INP_RUNLOCK(inp);
1269                 m_freem(m);
1270                 return (error);
1271         }
1272
1273         /*
1274          * In the old days, depending on whether or not the application had
1275          * bound or connected the socket, we had to do varying levels of work.
1276          * The optimal case was for a connected UDP socket, as a global lock
1277          * wasn't required at all.
1278          * In order to decide which we need, we required stability of the
1279          * inpcb binding, which we ensured by acquiring a read lock on the
1280          * inpcb.  This didn't strictly follow the lock order, so we played
1281          * the trylock and retry game.
1282          * With the re-introduction of the route-cache in some cases, we started
1283          * to acquire an early inp wlock and a possible race during re-lock
1284          * went away.  With the introduction of epoch(9) some read locking
1285          * became epoch(9) and the lock-order issues also went away.
1286          * Due to route-cache we may now hold more conservative locks than
1287          * otherwise required and have split up the 2nd case in case 2 and 3
1288          * in order to keep the udpinfo lock level in sync with the inp one
1289          * for the IP_SENDSRCADDR case below.
1290          */
1291         pr = inp->inp_socket->so_proto->pr_protocol;
1292         pcbinfo = udp_get_inpcbinfo(pr);
1293         if (sin != NULL &&
1294             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) {
1295                 INP_HASH_WLOCK(pcbinfo);
1296                 unlock_udbinfo = UH_WLOCKED;
1297         } else if (sin != NULL &&
1298             (sin->sin_addr.s_addr == INADDR_ANY ||
1299             sin->sin_addr.s_addr == INADDR_BROADCAST ||
1300             inp->inp_laddr.s_addr == INADDR_ANY ||
1301             inp->inp_lport == 0)) {
1302                 INP_HASH_RLOCK_ET(pcbinfo, et);
1303                 unlock_udbinfo = UH_RLOCKED;
1304         } else if (src.sin_family == AF_INET) {
1305                 if (unlock_inp == UH_WLOCKED) {
1306                         INP_HASH_WLOCK(pcbinfo);
1307                         unlock_udbinfo = UH_WLOCKED;
1308                 } else {
1309                         INP_HASH_RLOCK_ET(pcbinfo, et);
1310                         unlock_udbinfo = UH_RLOCKED;
1311                 }
1312         } else
1313                 unlock_udbinfo = UH_UNLOCKED;
1314
1315         /*
1316          * If the IP_SENDSRCADDR control message was specified, override the
1317          * source address for this datagram.  Its use is invalidated if the
1318          * address thus specified is incomplete or clobbers other inpcbs.
1319          */
1320         laddr = inp->inp_laddr;
1321         lport = inp->inp_lport;
1322         if (src.sin_family == AF_INET) {
1323                 INP_HASH_LOCK_ASSERT(pcbinfo);
1324                 if ((lport == 0) ||
1325                     (laddr.s_addr == INADDR_ANY &&
1326                      src.sin_addr.s_addr == INADDR_ANY)) {
1327                         error = EINVAL;
1328                         goto release;
1329                 }
1330                 error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
1331                     &laddr.s_addr, &lport, td->td_ucred);
1332                 if (error)
1333                         goto release;
1334         }
1335
1336         /*
1337          * If a UDP socket has been connected, then a local address/port will
1338          * have been selected and bound.
1339          *
1340          * If a UDP socket has not been connected to, then an explicit
1341          * destination address must be used, in which case a local
1342          * address/port may not have been selected and bound.
1343          */
1344         if (sin != NULL) {
1345                 INP_LOCK_ASSERT(inp);
1346                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1347                         error = EISCONN;
1348                         goto release;
1349                 }
1350
1351                 /*
1352                  * Jail may rewrite the destination address, so let it do
1353                  * that before we use it.
1354                  */
1355                 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1356                 if (error)
1357                         goto release;
1358
1359                 /*
1360                  * If a local address or port hasn't yet been selected, or if
1361                  * the destination address needs to be rewritten due to using
1362                  * a special INADDR_ constant, invoke in_pcbconnect_setup()
1363                  * to do the heavy lifting.  Once a port is selected, we
1364                  * commit the binding back to the socket; we also commit the
1365                  * binding of the address if in jail.
1366                  *
1367                  * If we already have a valid binding and we're not
1368                  * requesting a destination address rewrite, use a fast path.
1369                  */
1370                 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1371                     inp->inp_lport == 0 ||
1372                     sin->sin_addr.s_addr == INADDR_ANY ||
1373                     sin->sin_addr.s_addr == INADDR_BROADCAST) {
1374                         INP_HASH_LOCK_ASSERT(pcbinfo);
1375                         error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
1376                             &lport, &faddr.s_addr, &fport, NULL,
1377                             td->td_ucred);
1378                         if (error)
1379                                 goto release;
1380
1381                         /*
1382                          * XXXRW: Why not commit the port if the address is
1383                          * !INADDR_ANY?
1384                          */
1385                         /* Commit the local port if newly assigned. */
1386                         if (inp->inp_laddr.s_addr == INADDR_ANY &&
1387                             inp->inp_lport == 0) {
1388                                 INP_WLOCK_ASSERT(inp);
1389                                 INP_HASH_WLOCK_ASSERT(pcbinfo);
1390                                 /*
1391                                  * Remember addr if jailed, to prevent
1392                                  * rebinding.
1393                                  */
1394                                 if (prison_flag(td->td_ucred, PR_IP4))
1395                                         inp->inp_laddr = laddr;
1396                                 inp->inp_lport = lport;
1397                                 if (in_pcbinshash(inp) != 0) {
1398                                         inp->inp_lport = 0;
1399                                         error = EAGAIN;
1400                                         goto release;
1401                                 }
1402                                 inp->inp_flags |= INP_ANONPORT;
1403                         }
1404                 } else {
1405                         faddr = sin->sin_addr;
1406                         fport = sin->sin_port;
1407                 }
1408         } else {
1409                 INP_LOCK_ASSERT(inp);
1410                 faddr = inp->inp_faddr;
1411                 fport = inp->inp_fport;
1412                 if (faddr.s_addr == INADDR_ANY) {
1413                         error = ENOTCONN;
1414                         goto release;
1415                 }
1416         }
1417
1418         /*
1419          * Calculate data length and get a mbuf for UDP, IP, and possible
1420          * link-layer headers.  Immediate slide the data pointer back forward
1421          * since we won't use that space at this layer.
1422          */
1423         M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1424         if (m == NULL) {
1425                 error = ENOBUFS;
1426                 goto release;
1427         }
1428         m->m_data += max_linkhdr;
1429         m->m_len -= max_linkhdr;
1430         m->m_pkthdr.len -= max_linkhdr;
1431
1432         /*
1433          * Fill in mbuf with extended UDP header and addresses and length put
1434          * into network format.
1435          */
1436         ui = mtod(m, struct udpiphdr *);
1437         bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1438         ui->ui_v = IPVERSION << 4;
1439         ui->ui_pr = pr;
1440         ui->ui_src = laddr;
1441         ui->ui_dst = faddr;
1442         ui->ui_sport = lport;
1443         ui->ui_dport = fport;
1444         ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1445         if (pr == IPPROTO_UDPLITE) {
1446                 struct udpcb *up;
1447                 uint16_t plen;
1448
1449                 up = intoudpcb(inp);
1450                 cscov = up->u_txcslen;
1451                 plen = (u_short)len + sizeof(struct udphdr);
1452                 if (cscov >= plen)
1453                         cscov = 0;
1454                 ui->ui_len = htons(plen);
1455                 ui->ui_ulen = htons(cscov);
1456                 /*
1457                  * For UDP-Lite, checksum coverage length of zero means
1458                  * the entire UDPLite packet is covered by the checksum.
1459                  */
1460                 cscov_partial = (cscov == 0) ? 0 : 1;
1461         }
1462
1463         /*
1464          * Set the Don't Fragment bit in the IP header.
1465          */
1466         if (inp->inp_flags & INP_DONTFRAG) {
1467                 struct ip *ip;
1468
1469                 ip = (struct ip *)&ui->ui_i;
1470                 ip->ip_off |= htons(IP_DF);
1471         }
1472
1473         ipflags = 0;
1474         if (inp->inp_socket->so_options & SO_DONTROUTE)
1475                 ipflags |= IP_ROUTETOIF;
1476         if (inp->inp_socket->so_options & SO_BROADCAST)
1477                 ipflags |= IP_ALLOWBROADCAST;
1478         if (inp->inp_flags & INP_ONESBCAST)
1479                 ipflags |= IP_SENDONES;
1480
1481 #ifdef MAC
1482         mac_inpcb_create_mbuf(inp, m);
1483 #endif
1484
1485         /*
1486          * Set up checksum and output datagram.
1487          */
1488         ui->ui_sum = 0;
1489         if (pr == IPPROTO_UDPLITE) {
1490                 if (inp->inp_flags & INP_ONESBCAST)
1491                         faddr.s_addr = INADDR_BROADCAST;
1492                 if (cscov_partial) {
1493                         if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1494                                 ui->ui_sum = 0xffff;
1495                 } else {
1496                         if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1497                                 ui->ui_sum = 0xffff;
1498                 }
1499         } else if (V_udp_cksum) {
1500                 if (inp->inp_flags & INP_ONESBCAST)
1501                         faddr.s_addr = INADDR_BROADCAST;
1502                 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1503                     htons((u_short)len + sizeof(struct udphdr) + pr));
1504                 m->m_pkthdr.csum_flags = CSUM_UDP;
1505                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1506         }
1507         ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1508         ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1509         ((struct ip *)ui)->ip_tos = tos;                /* XXX */
1510         UDPSTAT_INC(udps_opackets);
1511
1512         /*
1513          * Setup flowid / RSS information for outbound socket.
1514          *
1515          * Once the UDP code decides to set a flowid some other way,
1516          * this allows the flowid to be overridden by userland.
1517          */
1518         if (flowtype != M_HASHTYPE_NONE) {
1519                 m->m_pkthdr.flowid = flowid;
1520                 M_HASHTYPE_SET(m, flowtype);
1521         }
1522 #ifdef  RSS
1523         else {
1524                 uint32_t hash_val, hash_type;
1525                 /*
1526                  * Calculate an appropriate RSS hash for UDP and
1527                  * UDP Lite.
1528                  *
1529                  * The called function will take care of figuring out
1530                  * whether a 2-tuple or 4-tuple hash is required based
1531                  * on the currently configured scheme.
1532                  *
1533                  * Later later on connected socket values should be
1534                  * cached in the inpcb and reused, rather than constantly
1535                  * re-calculating it.
1536                  *
1537                  * UDP Lite is a different protocol number and will
1538                  * likely end up being hashed as a 2-tuple until
1539                  * RSS / NICs grow UDP Lite protocol awareness.
1540                  */
1541                 if (rss_proto_software_hash_v4(faddr, laddr, fport, lport,
1542                     pr, &hash_val, &hash_type) == 0) {
1543                         m->m_pkthdr.flowid = hash_val;
1544                         M_HASHTYPE_SET(m, hash_type);
1545                 }
1546         }
1547
1548         /*
1549          * Don't override with the inp cached flowid value.
1550          *
1551          * Depending upon the kind of send being done, the inp
1552          * flowid/flowtype values may actually not be appropriate
1553          * for this particular socket send.
1554          *
1555          * We should either leave the flowid at zero (which is what is
1556          * currently done) or set it to some software generated
1557          * hash value based on the packet contents.
1558          */
1559         ipflags |= IP_NODEFAULTFLOWID;
1560 #endif  /* RSS */
1561
1562         if (unlock_udbinfo == UH_WLOCKED)
1563                 INP_HASH_WUNLOCK(pcbinfo);
1564         else if (unlock_udbinfo == UH_RLOCKED)
1565                 INP_HASH_RUNLOCK_ET(pcbinfo, et);
1566         if (pr == IPPROTO_UDPLITE)
1567                 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1568         else
1569                 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1570         error = ip_output(m, inp->inp_options,
1571             (unlock_inp == UH_WLOCKED ? &inp->inp_route : NULL), ipflags,
1572             inp->inp_moptions, inp);
1573         if (unlock_inp == UH_WLOCKED)
1574                 INP_WUNLOCK(inp);
1575         else
1576                 INP_RUNLOCK(inp);
1577         return (error);
1578
1579 release:
1580         if (unlock_udbinfo == UH_WLOCKED) {
1581                 KASSERT(unlock_inp == UH_WLOCKED,
1582                     ("%s: excl udbinfo lock %#03x, shared inp lock %#03x, "
1583                     "sin %p daddr %#010x inp %p laddr %#010x lport %#06x "
1584                     "src fam %#04x",
1585                     __func__, unlock_udbinfo, unlock_inp, sin,
1586                     (sin != NULL) ? sin->sin_addr.s_addr : 0xfefefefe, inp,
1587                     inp->inp_laddr.s_addr, inp->inp_lport, src.sin_family));
1588                 INP_HASH_WUNLOCK(pcbinfo);
1589                 INP_WUNLOCK(inp);
1590         } else if (unlock_udbinfo == UH_RLOCKED) {
1591                 KASSERT(unlock_inp == UH_RLOCKED,
1592                     ("%s: shared udbinfo lock %#03x, excl inp lock %#03x, "
1593                     "sin %p daddr %#010x inp %p laddr %#010x lport %#06x "
1594                     "src fam %#04x",
1595                     __func__, unlock_udbinfo, unlock_inp, sin,
1596                     (sin != NULL) ? sin->sin_addr.s_addr : 0xfefefefe, inp,
1597                     inp->inp_laddr.s_addr, inp->inp_lport, src.sin_family));
1598                 INP_HASH_RUNLOCK_ET(pcbinfo, et);
1599                 INP_RUNLOCK(inp);
1600         } else if (unlock_inp == UH_WLOCKED)
1601                 INP_WUNLOCK(inp);
1602         else
1603                 INP_RUNLOCK(inp);
1604         m_freem(m);
1605         return (error);
1606 }
1607
1608 static void
1609 udp_abort(struct socket *so)
1610 {
1611         struct inpcb *inp;
1612         struct inpcbinfo *pcbinfo;
1613
1614         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1615         inp = sotoinpcb(so);
1616         KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1617         INP_WLOCK(inp);
1618         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1619                 INP_HASH_WLOCK(pcbinfo);
1620                 in_pcbdisconnect(inp);
1621                 inp->inp_laddr.s_addr = INADDR_ANY;
1622                 INP_HASH_WUNLOCK(pcbinfo);
1623                 soisdisconnected(so);
1624         }
1625         INP_WUNLOCK(inp);
1626 }
1627
1628 static int
1629 udp_attach(struct socket *so, int proto, struct thread *td)
1630 {
1631         static uint32_t udp_flowid;
1632         struct inpcb *inp;
1633         struct inpcbinfo *pcbinfo;
1634         int error;
1635
1636         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1637         inp = sotoinpcb(so);
1638         KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1639         error = soreserve(so, udp_sendspace, udp_recvspace);
1640         if (error)
1641                 return (error);
1642         INP_INFO_WLOCK(pcbinfo);
1643         error = in_pcballoc(so, pcbinfo);
1644         if (error) {
1645                 INP_INFO_WUNLOCK(pcbinfo);
1646                 return (error);
1647         }
1648
1649         inp = sotoinpcb(so);
1650         inp->inp_vflag |= INP_IPV4;
1651         inp->inp_ip_ttl = V_ip_defttl;
1652         inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1653         inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1654
1655         error = udp_newudpcb(inp);
1656         if (error) {
1657                 in_pcbdetach(inp);
1658                 in_pcbfree(inp);
1659                 INP_INFO_WUNLOCK(pcbinfo);
1660                 return (error);
1661         }
1662
1663         INP_WUNLOCK(inp);
1664         INP_INFO_WUNLOCK(pcbinfo);
1665         return (0);
1666 }
1667 #endif /* INET */
1668
1669 int
1670 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1671 {
1672         struct inpcb *inp;
1673         struct udpcb *up;
1674
1675         KASSERT(so->so_type == SOCK_DGRAM,
1676             ("udp_set_kernel_tunneling: !dgram"));
1677         inp = sotoinpcb(so);
1678         KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1679         INP_WLOCK(inp);
1680         up = intoudpcb(inp);
1681         if ((up->u_tun_func != NULL) ||
1682             (up->u_icmp_func != NULL)) {
1683                 INP_WUNLOCK(inp);
1684                 return (EBUSY);
1685         }
1686         up->u_tun_func = f;
1687         up->u_icmp_func = i;
1688         up->u_tun_ctx = ctx;
1689         INP_WUNLOCK(inp);
1690         return (0);
1691 }
1692
1693 #ifdef INET
1694 static int
1695 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1696 {
1697         struct inpcb *inp;
1698         struct inpcbinfo *pcbinfo;
1699         int error;
1700
1701         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1702         inp = sotoinpcb(so);
1703         KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1704         INP_WLOCK(inp);
1705         INP_HASH_WLOCK(pcbinfo);
1706         error = in_pcbbind(inp, nam, td->td_ucred);
1707         INP_HASH_WUNLOCK(pcbinfo);
1708         INP_WUNLOCK(inp);
1709         return (error);
1710 }
1711
1712 static void
1713 udp_close(struct socket *so)
1714 {
1715         struct inpcb *inp;
1716         struct inpcbinfo *pcbinfo;
1717
1718         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1719         inp = sotoinpcb(so);
1720         KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1721         INP_WLOCK(inp);
1722         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1723                 INP_HASH_WLOCK(pcbinfo);
1724                 in_pcbdisconnect(inp);
1725                 inp->inp_laddr.s_addr = INADDR_ANY;
1726                 INP_HASH_WUNLOCK(pcbinfo);
1727                 soisdisconnected(so);
1728         }
1729         INP_WUNLOCK(inp);
1730 }
1731
1732 static int
1733 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1734 {
1735         struct inpcb *inp;
1736         struct inpcbinfo *pcbinfo;
1737         struct sockaddr_in *sin;
1738         int error;
1739
1740         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1741         inp = sotoinpcb(so);
1742         KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1743         INP_WLOCK(inp);
1744         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1745                 INP_WUNLOCK(inp);
1746                 return (EISCONN);
1747         }
1748         sin = (struct sockaddr_in *)nam;
1749         error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1750         if (error != 0) {
1751                 INP_WUNLOCK(inp);
1752                 return (error);
1753         }
1754         INP_HASH_WLOCK(pcbinfo);
1755         error = in_pcbconnect(inp, nam, td->td_ucred);
1756         INP_HASH_WUNLOCK(pcbinfo);
1757         if (error == 0)
1758                 soisconnected(so);
1759         INP_WUNLOCK(inp);
1760         return (error);
1761 }
1762
1763 static void
1764 udp_detach(struct socket *so)
1765 {
1766         struct inpcb *inp;
1767         struct inpcbinfo *pcbinfo;
1768         struct udpcb *up;
1769
1770         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1771         inp = sotoinpcb(so);
1772         KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1773         KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1774             ("udp_detach: not disconnected"));
1775         INP_INFO_WLOCK(pcbinfo);
1776         INP_WLOCK(inp);
1777         up = intoudpcb(inp);
1778         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1779         inp->inp_ppcb = NULL;
1780         in_pcbdetach(inp);
1781         in_pcbfree(inp);
1782         INP_INFO_WUNLOCK(pcbinfo);
1783         udp_discardcb(up);
1784 }
1785
1786 static int
1787 udp_disconnect(struct socket *so)
1788 {
1789         struct inpcb *inp;
1790         struct inpcbinfo *pcbinfo;
1791
1792         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1793         inp = sotoinpcb(so);
1794         KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1795         INP_WLOCK(inp);
1796         if (inp->inp_faddr.s_addr == INADDR_ANY) {
1797                 INP_WUNLOCK(inp);
1798                 return (ENOTCONN);
1799         }
1800         INP_HASH_WLOCK(pcbinfo);
1801         in_pcbdisconnect(inp);
1802         inp->inp_laddr.s_addr = INADDR_ANY;
1803         INP_HASH_WUNLOCK(pcbinfo);
1804         SOCK_LOCK(so);
1805         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1806         SOCK_UNLOCK(so);
1807         INP_WUNLOCK(inp);
1808         return (0);
1809 }
1810
1811 static int
1812 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1813     struct mbuf *control, struct thread *td)
1814 {
1815         struct inpcb *inp;
1816
1817         inp = sotoinpcb(so);
1818         KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1819         return (udp_output(inp, m, addr, control, td));
1820 }
1821 #endif /* INET */
1822
1823 int
1824 udp_shutdown(struct socket *so)
1825 {
1826         struct inpcb *inp;
1827
1828         inp = sotoinpcb(so);
1829         KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1830         INP_WLOCK(inp);
1831         socantsendmore(so);
1832         INP_WUNLOCK(inp);
1833         return (0);
1834 }
1835
1836 #ifdef INET
1837 struct pr_usrreqs udp_usrreqs = {
1838         .pru_abort =            udp_abort,
1839         .pru_attach =           udp_attach,
1840         .pru_bind =             udp_bind,
1841         .pru_connect =          udp_connect,
1842         .pru_control =          in_control,
1843         .pru_detach =           udp_detach,
1844         .pru_disconnect =       udp_disconnect,
1845         .pru_peeraddr =         in_getpeeraddr,
1846         .pru_send =             udp_send,
1847         .pru_soreceive =        soreceive_dgram,
1848         .pru_sosend =           sosend_dgram,
1849         .pru_shutdown =         udp_shutdown,
1850         .pru_sockaddr =         in_getsockaddr,
1851         .pru_sosetlabel =       in_pcbsosetlabel,
1852         .pru_close =            udp_close,
1853 };
1854 #endif /* INET */