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         int cscov_partial, iphlen;
 403
 404         m = *mp;
 405         iphlen = *offp;
 406         ifp = m->m_pkthdr.rcvif;
 407         *mp = NULL;
 408         UDPSTAT_INC(udps_ipackets);
 409
 410         /*
 411          * Strip IP options, if any; should skip this, make available to
 412          * user, and use on returned packets, but we don't yet have a way to
 413          * check the checksum with options still present.
 414          */
 415         if (iphlen > sizeof (struct ip)) {
 416                 ip_stripoptions(m);
 417                 iphlen = sizeof(struct ip);
 418         }
 419
 420         /*
 421          * Get IP and UDP header together in first mbuf.
 422          */
 423         if (m->m_len < iphlen + sizeof(struct udphdr)) {
 424                 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
 425                         UDPSTAT_INC(udps_hdrops);
 426                         return (IPPROTO_DONE);
 427                 }
 428         }
 429         ip = mtod(m, struct ip *);
 430         uh = (struct udphdr *)((caddr_t)ip + iphlen);
 431         cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
 432
 433         /*
 434          * Destination port of 0 is illegal, based on RFC768.
 435          */
 436         if (uh->uh_dport == 0)
 437                 goto badunlocked;
 438
 439         /*
 440          * Construct sockaddr format source address.  Stuff source address
 441          * and datagram in user buffer.
 442          */
 443         bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
 444         udp_in[0].sin_len = sizeof(struct sockaddr_in);
 445         udp_in[0].sin_family = AF_INET;
 446         udp_in[0].sin_port = uh->uh_sport;
 447         udp_in[0].sin_addr = ip->ip_src;
 448         udp_in[1].sin_len = sizeof(struct sockaddr_in);
 449         udp_in[1].sin_family = AF_INET;
 450         udp_in[1].sin_port = uh->uh_dport;
 451         udp_in[1].sin_addr = ip->ip_dst;
 452
 453         /*
 454          * Make mbuf data length reflect UDP length.  If not enough data to
 455          * reflect UDP length, drop.
 456          */
 457         len = ntohs((u_short)uh->uh_ulen);
 458         ip_len = ntohs(ip->ip_len) - iphlen;
 459         if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
 460                 /* Zero means checksum over the complete packet. */
 461                 if (len == 0)
 462                         len = ip_len;
 463                 cscov_partial = 0;
 464         }
 465         if (ip_len != len) {
 466                 if (len > ip_len || len < sizeof(struct udphdr)) {
 467                         UDPSTAT_INC(udps_badlen);
 468                         goto badunlocked;
 469                 }
 470                 if (proto == IPPROTO_UDP)
 471                         m_adj(m, len - ip_len);
 472         }
 473
 474         /*
 475          * Save a copy of the IP header in case we want restore it for
 476          * sending an ICMP error message in response.
 477          */
 478         if (!V_udp_blackhole)
 479                 save_ip = *ip;
 480         else
 481                 memset(&save_ip, 0, sizeof(save_ip));
 482
 483         /*
 484          * Checksum extended UDP header and data.
 485          */
 486         if (uh->uh_sum) {
 487                 u_short uh_sum;
 488
 489                 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
 490                     !cscov_partial) {
 491                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 492                                 uh_sum = m->m_pkthdr.csum_data;
 493                         else
 494                                 uh_sum = in_pseudo(ip->ip_src.s_addr,
 495                                     ip->ip_dst.s_addr, htonl((u_short)len +
 496                                     m->m_pkthdr.csum_data + proto));
 497                         uh_sum ^= 0xffff;
 498                 } else {
 499                         char b[9];
 500
 501                         bcopy(((struct ipovly *)ip)->ih_x1, b, 9);
 502                         bzero(((struct ipovly *)ip)->ih_x1, 9);
 503                         ((struct ipovly *)ip)->ih_len = (proto == IPPROTO_UDP) ?
 504                             uh->uh_ulen : htons(ip_len);
 505                         uh_sum = in_cksum(m, len + sizeof (struct ip));
 506                         bcopy(b, ((struct ipovly *)ip)->ih_x1, 9);
 507                 }
 508                 if (uh_sum) {
 509                         UDPSTAT_INC(udps_badsum);
 510                         m_freem(m);
 511                         return (IPPROTO_DONE);
 512                 }
 513         } else {
 514                 if (proto == IPPROTO_UDP) {
 515                         UDPSTAT_INC(udps_nosum);
 516                 } else {
 517                         /* UDPLite requires a checksum */
 518                         /* XXX: What is the right UDPLite MIB counter here? */
 519                         m_freem(m);
 520                         return (IPPROTO_DONE);
 521                 }
 522         }
 523
 524         pcbinfo = udp_get_inpcbinfo(proto);
 525         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
 526             in_broadcast(ip->ip_dst, ifp)) {
 527                 struct inpcb *last;
 528                 struct inpcbhead *pcblist;
 529
 530                 NET_EPOCH_ASSERT();
 531
 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                         goto badunlocked;
 639                 }
 640                 if (proto == IPPROTO_UDPLITE)
 641                         UDPLITE_PROBE(receive, NULL, last, ip, last, uh);
 642                 else
 643                         UDP_PROBE(receive, NULL, last, ip, last, uh);
 644                 if (udp_append(last, ip, m, iphlen, udp_in) == 0)
 645                         INP_RUNLOCK(last);
 646         inp_lost:
 647                 return (IPPROTO_DONE);
 648         }
 649
 650         /*
 651          * Locate pcb for datagram.
 652          */
 653
 654         /*
 655          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 656          */
 657         if ((m->m_flags & M_IP_NEXTHOP) &&
 658             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 659                 struct sockaddr_in *next_hop;
 660
 661                 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
 662
 663                 /*
 664                  * Transparently forwarded. Pretend to be the destination.
 665                  * Already got one like this?
 666                  */
 667                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 668                     ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
 669                 if (!inp) {
 670                         /*
 671                          * It's new.  Try to find the ambushing socket.
 672                          * Because we've rewritten the destination address,
 673                          * any hardware-generated hash is ignored.
 674                          */
 675                         inp = in_pcblookup(pcbinfo, ip->ip_src,
 676                             uh->uh_sport, next_hop->sin_addr,
 677                             next_hop->sin_port ? htons(next_hop->sin_port) :
 678                             uh->uh_dport, INPLOOKUP_WILDCARD |
 679                             INPLOOKUP_RLOCKPCB, ifp);
 680                 }
 681                 /* Remove the tag from the packet. We don't need it anymore. */
 682                 m_tag_delete(m, fwd_tag);
 683                 m->m_flags &= ~M_IP_NEXTHOP;
 684         } else
 685                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 686                     ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
 687                     INPLOOKUP_RLOCKPCB, ifp, m);
 688         if (inp == NULL) {
 689                 if (udp_log_in_vain) {
 690                         char src[INET_ADDRSTRLEN];
 691                         char dst[INET_ADDRSTRLEN];
 692
 693                         log(LOG_INFO,
 694                             "Connection attempt to UDP %s:%d from %s:%d\n",
 695                             inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
 696                             inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
 697                 }
 698                 if (proto == IPPROTO_UDPLITE)
 699                         UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
 700                 else
 701                         UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
 702                 UDPSTAT_INC(udps_noport);
 703                 if (m->m_flags & (M_BCAST | M_MCAST)) {
 704                         UDPSTAT_INC(udps_noportbcast);
 705                         goto badunlocked;
 706                 }
 707                 if (V_udp_blackhole)
 708                         goto badunlocked;
 709                 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
 710                         goto badunlocked;
 711                 *ip = save_ip;
 712                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
 713                 return (IPPROTO_DONE);
 714         }
 715
 716         /*
 717          * Check the minimum TTL for socket.
 718          */
 719         INP_RLOCK_ASSERT(inp);
 720         if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
 721                 if (proto == IPPROTO_UDPLITE)
 722                         UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 723                 else
 724                         UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 725                 INP_RUNLOCK(inp);
 726                 m_freem(m);
 727                 return (IPPROTO_DONE);
 728         }
 729         if (cscov_partial) {
 730                 struct udpcb *up;
 731
 732                 up = intoudpcb(inp);
 733                 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
 734                         INP_RUNLOCK(inp);
 735                         m_freem(m);
 736                         return (IPPROTO_DONE);
 737                 }
 738         }
 739
 740         if (proto == IPPROTO_UDPLITE)
 741                 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 742         else
 743                 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 744         if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
 745                 INP_RUNLOCK(inp);
 746         return (IPPROTO_DONE);
 747
 748 badunlocked:
 749         m_freem(m);
 750         return (IPPROTO_DONE);
 751 }
 752 #endif /* INET */
 753
 754 /*
 755  * Notify a udp user of an asynchronous error; just wake up so that they can
 756  * collect error status.
 757  */
 758 struct inpcb *
 759 udp_notify(struct inpcb *inp, int errno)
 760 {
 761
 762         INP_WLOCK_ASSERT(inp);
 763         if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
 764              errno == EHOSTDOWN) && inp->inp_route.ro_rt) {
 765                 RTFREE(inp->inp_route.ro_rt);
 766                 inp->inp_route.ro_rt = (struct rtentry *)NULL;
 767         }
 768
 769         inp->inp_socket->so_error = errno;
 770         sorwakeup(inp->inp_socket);
 771         sowwakeup(inp->inp_socket);
 772         return (inp);
 773 }
 774
 775 #ifdef INET
 776 static void
 777 udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip,
 778     struct inpcbinfo *pcbinfo)
 779 {
 780         struct ip *ip = vip;
 781         struct udphdr *uh;
 782         struct in_addr faddr;
 783         struct inpcb *inp;
 784
 785         faddr = ((struct sockaddr_in *)sa)->sin_addr;
 786         if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
 787                 return;
 788
 789         if (PRC_IS_REDIRECT(cmd)) {
 790                 /* signal EHOSTDOWN, as it flushes the cached route */
 791                 in_pcbnotifyall(&V_udbinfo, faddr, EHOSTDOWN, udp_notify);
 792                 return;
 793         }
 794
 795         /*
 796          * Hostdead is ugly because it goes linearly through all PCBs.
 797          *
 798          * XXX: We never get this from ICMP, otherwise it makes an excellent
 799          * DoS attack on machines with many connections.
 800          */
 801         if (cmd == PRC_HOSTDEAD)
 802                 ip = NULL;
 803         else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
 804                 return;
 805         if (ip != NULL) {
 806                 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 807                 inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 808                     ip->ip_src, uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
 809                 if (inp != NULL) {
 810                         INP_WLOCK_ASSERT(inp);
 811                         if (inp->inp_socket != NULL) {
 812                                 udp_notify(inp, inetctlerrmap[cmd]);
 813                         }
 814                         INP_WUNLOCK(inp);
 815                 } else {
 816                         inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport,
 817                                            ip->ip_src, uh->uh_sport,
 818                                            INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 819                         if (inp != NULL) {
 820                                 struct udpcb *up;
 821                                 void *ctx;
 822                                 udp_tun_icmp_t func;
 823
 824                                 up = intoudpcb(inp);
 825                                 ctx = up->u_tun_ctx;
 826                                 func = up->u_icmp_func;
 827                                 INP_RUNLOCK(inp);
 828                                 if (func != NULL)
 829                                         (*func)(cmd, sa, vip, ctx);
 830                         }
 831                 }
 832         } else
 833                 in_pcbnotifyall(pcbinfo, faddr, inetctlerrmap[cmd],
 834                     udp_notify);
 835 }
 836 void
 837 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 838 {
 839
 840         return (udp_common_ctlinput(cmd, sa, vip, &V_udbinfo));
 841 }
 842
 843 void
 844 udplite_ctlinput(int cmd, struct sockaddr *sa, void *vip)
 845 {
 846
 847         return (udp_common_ctlinput(cmd, sa, vip, &V_ulitecbinfo));
 848 }
 849 #endif /* INET */
 850
 851 static int
 852 udp_pcblist(SYSCTL_HANDLER_ARGS)
 853 {
 854         struct xinpgen xig;
 855         struct epoch_tracker et;
 856         struct inpcb *inp;
 857         int error;
 858
 859         if (req->newptr != 0)
 860                 return (EPERM);
 861
 862         if (req->oldptr == 0) {
 863                 int n;
 864
 865                 n = V_udbinfo.ipi_count;
 866                 n += imax(n / 8, 10);
 867                 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
 868                 return (0);
 869         }
 870
 871         if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
 872                 return (error);
 873
 874         bzero(&xig, sizeof(xig));
 875         xig.xig_len = sizeof xig;
 876         xig.xig_count = V_udbinfo.ipi_count;
 877         xig.xig_gen = V_udbinfo.ipi_gencnt;
 878         xig.xig_sogen = so_gencnt;
 879         error = SYSCTL_OUT(req, &xig, sizeof xig);
 880         if (error)
 881                 return (error);
 882
 883         NET_EPOCH_ENTER(et);
 884         for (inp = CK_LIST_FIRST(V_udbinfo.ipi_listhead);
 885             inp != NULL;
 886             inp = CK_LIST_NEXT(inp, inp_list)) {
 887                 INP_RLOCK(inp);
 888                 if (inp->inp_gencnt <= xig.xig_gen &&
 889                     cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
 890                         struct xinpcb xi;
 891
 892                         in_pcbtoxinpcb(inp, &xi);
 893                         INP_RUNLOCK(inp);
 894                         error = SYSCTL_OUT(req, &xi, sizeof xi);
 895                         if (error)
 896                                 break;
 897                 } else
 898                         INP_RUNLOCK(inp);
 899         }
 900         NET_EPOCH_EXIT(et);
 901
 902         if (!error) {
 903                 /*
 904                  * Give the user an updated idea of our state.  If the
 905                  * generation differs from what we told her before, she knows
 906                  * that something happened while we were processing this
 907                  * request, and it might be necessary to retry.
 908                  */
 909                 xig.xig_gen = V_udbinfo.ipi_gencnt;
 910                 xig.xig_sogen = so_gencnt;
 911                 xig.xig_count = V_udbinfo.ipi_count;
 912                 error = SYSCTL_OUT(req, &xig, sizeof xig);
 913         }
 914
 915         return (error);
 916 }
 917
 918 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
 919     CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
 920     udp_pcblist, "S,xinpcb", "List of active UDP sockets");
 921
 922 #ifdef INET
 923 static int
 924 udp_getcred(SYSCTL_HANDLER_ARGS)
 925 {
 926         struct xucred xuc;
 927         struct sockaddr_in addrs[2];
 928         struct epoch_tracker et;
 929         struct inpcb *inp;
 930         int error;
 931
 932         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 933         if (error)
 934                 return (error);
 935         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 936         if (error)
 937                 return (error);
 938         NET_EPOCH_ENTER(et);
 939         inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
 940             addrs[0].sin_addr, addrs[0].sin_port,
 941             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 942         NET_EPOCH_EXIT(et);
 943         if (inp != NULL) {
 944                 INP_RLOCK_ASSERT(inp);
 945                 if (inp->inp_socket == NULL)
 946                         error = ENOENT;
 947                 if (error == 0)
 948                         error = cr_canseeinpcb(req->td->td_ucred, inp);
 949                 if (error == 0)
 950                         cru2x(inp->inp_cred, &xuc);
 951                 INP_RUNLOCK(inp);
 952         } else
 953                 error = ENOENT;
 954         if (error == 0)
 955                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 956         return (error);
 957 }
 958
 959 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
 960     CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
 961     udp_getcred, "S,xucred", "Get the xucred of a UDP connection");
 962 #endif /* INET */
 963
 964 int
 965 udp_ctloutput(struct socket *so, struct sockopt *sopt)
 966 {
 967         struct inpcb *inp;
 968         struct udpcb *up;
 969         int isudplite, error, optval;
 970
 971         error = 0;
 972         isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
 973         inp = sotoinpcb(so);
 974         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 975         INP_WLOCK(inp);
 976         if (sopt->sopt_level != so->so_proto->pr_protocol) {
 977 #ifdef INET6
 978                 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
 979                         INP_WUNLOCK(inp);
 980                         error = ip6_ctloutput(so, sopt);
 981                 }
 982 #endif
 983 #if defined(INET) && defined(INET6)
 984                 else
 985 #endif
 986 #ifdef INET
 987                 {
 988                         INP_WUNLOCK(inp);
 989                         error = ip_ctloutput(so, sopt);
 990                 }
 991 #endif
 992                 return (error);
 993         }
 994
 995         switch (sopt->sopt_dir) {
 996         case SOPT_SET:
 997                 switch (sopt->sopt_name) {
 998 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 999 #ifdef INET
1000                 case UDP_ENCAP:
1001                         if (!IPSEC_ENABLED(ipv4)) {
1002                                 INP_WUNLOCK(inp);
1003                                 return (ENOPROTOOPT);
1004                         }
1005                         error = UDPENCAP_PCBCTL(inp, sopt);
1006                         break;
1007 #endif /* INET */
1008 #endif /* IPSEC */
1009                 case UDPLITE_SEND_CSCOV:
1010                 case UDPLITE_RECV_CSCOV:
1011                         if (!isudplite) {
1012                                 INP_WUNLOCK(inp);
1013                                 error = ENOPROTOOPT;
1014                                 break;
1015                         }
1016                         INP_WUNLOCK(inp);
1017                         error = sooptcopyin(sopt, &optval, sizeof(optval),
1018                             sizeof(optval));
1019                         if (error != 0)
1020                                 break;
1021                         inp = sotoinpcb(so);
1022                         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1023                         INP_WLOCK(inp);
1024                         up = intoudpcb(inp);
1025                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1026                         if ((optval != 0 && optval < 8) || (optval > 65535)) {
1027                                 INP_WUNLOCK(inp);
1028                                 error = EINVAL;
1029                                 break;
1030                         }
1031                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1032                                 up->u_txcslen = optval;
1033                         else
1034                                 up->u_rxcslen = optval;
1035                         INP_WUNLOCK(inp);
1036                         break;
1037                 default:
1038                         INP_WUNLOCK(inp);
1039                         error = ENOPROTOOPT;
1040                         break;
1041                 }
1042                 break;
1043         case SOPT_GET:
1044                 switch (sopt->sopt_name) {
1045 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1046 #ifdef INET
1047                 case UDP_ENCAP:
1048                         if (!IPSEC_ENABLED(ipv4)) {
1049                                 INP_WUNLOCK(inp);
1050                                 return (ENOPROTOOPT);
1051                         }
1052                         error = UDPENCAP_PCBCTL(inp, sopt);
1053                         break;
1054 #endif /* INET */
1055 #endif /* IPSEC */
1056                 case UDPLITE_SEND_CSCOV:
1057                 case UDPLITE_RECV_CSCOV:
1058                         if (!isudplite) {
1059                                 INP_WUNLOCK(inp);
1060                                 error = ENOPROTOOPT;
1061                                 break;
1062                         }
1063                         up = intoudpcb(inp);
1064                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1065                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
1066                                 optval = up->u_txcslen;
1067                         else
1068                                 optval = up->u_rxcslen;
1069                         INP_WUNLOCK(inp);
1070                         error = sooptcopyout(sopt, &optval, sizeof(optval));
1071                         break;
1072                 default:
1073                         INP_WUNLOCK(inp);
1074                         error = ENOPROTOOPT;
1075                         break;
1076                 }
1077                 break;
1078         }
1079         return (error);
1080 }
1081
1082 #ifdef INET
1083 static int
1084 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr,
1085     struct mbuf *control, struct thread *td)
1086 {
1087         struct udpiphdr *ui;
1088         int len = m->m_pkthdr.len;
1089         struct in_addr faddr, laddr;
1090         struct cmsghdr *cm;
1091         struct inpcbinfo *pcbinfo;
1092         struct sockaddr_in *sin, src;
1093         struct epoch_tracker et;
1094         int cscov_partial = 0;
1095         int error = 0;
1096         int ipflags;
1097         u_short fport, lport;
1098         u_char tos;
1099         uint8_t pr;
1100         uint16_t cscov = 0;
1101         uint32_t flowid = 0;
1102         uint8_t flowtype = M_HASHTYPE_NONE;
1103
1104         if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1105                 if (control)
1106                         m_freem(control);
1107                 m_freem(m);
1108                 return (EMSGSIZE);
1109         }
1110
1111         src.sin_family = 0;
1112         sin = (struct sockaddr_in *)addr;
1113
1114         /*
1115          * udp_output() may need to temporarily bind or connect the current
1116          * inpcb.  As such, we don't know up front whether we will need the
1117          * pcbinfo lock or not.  Do any work to decide what is needed up
1118          * front before acquiring any locks.
1119          *
1120          * We will need network epoch in either case, to safely lookup into
1121          * pcb hash.
1122          */
1123         if (sin == NULL ||
1124             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0))
1125                 INP_WLOCK(inp);
1126         else
1127                 INP_RLOCK(inp);
1128         NET_EPOCH_ENTER(et);
1129         tos = inp->inp_ip_tos;
1130         if (control != NULL) {
1131                 /*
1132                  * XXX: Currently, we assume all the optional information is
1133                  * stored in a single mbuf.
1134                  */
1135                 if (control->m_next) {
1136                         m_freem(control);
1137                         error = EINVAL;
1138                         goto release;
1139                 }
1140                 for (; control->m_len > 0;
1141                     control->m_data += CMSG_ALIGN(cm->cmsg_len),
1142                     control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1143                         cm = mtod(control, struct cmsghdr *);
1144                         if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1145                             || cm->cmsg_len > control->m_len) {
1146                                 error = EINVAL;
1147                                 break;
1148                         }
1149                         if (cm->cmsg_level != IPPROTO_IP)
1150                                 continue;
1151
1152                         switch (cm->cmsg_type) {
1153                         case IP_SENDSRCADDR:
1154                                 if (cm->cmsg_len !=
1155                                     CMSG_LEN(sizeof(struct in_addr))) {
1156                                         error = EINVAL;
1157                                         break;
1158                                 }
1159                                 bzero(&src, sizeof(src));
1160                                 src.sin_family = AF_INET;
1161                                 src.sin_len = sizeof(src);
1162                                 src.sin_port = inp->inp_lport;
1163                                 src.sin_addr =
1164                                     *(struct in_addr *)CMSG_DATA(cm);
1165                                 break;
1166
1167                         case IP_TOS:
1168                                 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1169                                         error = EINVAL;
1170                                         break;
1171                                 }
1172                                 tos = *(u_char *)CMSG_DATA(cm);
1173                                 break;
1174
1175                         case IP_FLOWID:
1176                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1177                                         error = EINVAL;
1178                                         break;
1179                                 }
1180                                 flowid = *(uint32_t *) CMSG_DATA(cm);
1181                                 break;
1182
1183                         case IP_FLOWTYPE:
1184                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1185                                         error = EINVAL;
1186                                         break;
1187                                 }
1188                                 flowtype = *(uint32_t *) CMSG_DATA(cm);
1189                                 break;
1190
1191 #ifdef  RSS
1192                         case IP_RSSBUCKETID:
1193                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1194                                         error = EINVAL;
1195                                         break;
1196                                 }
1197                                 /* This is just a placeholder for now */
1198                                 break;
1199 #endif  /* RSS */
1200                         default:
1201                                 error = ENOPROTOOPT;
1202                                 break;
1203                         }
1204                         if (error)
1205                                 break;
1206                 }
1207                 m_freem(control);
1208         }
1209         if (error)
1210                 goto release;
1211
1212         pr = inp->inp_socket->so_proto->pr_protocol;
1213         pcbinfo = udp_get_inpcbinfo(pr);
1214
1215         /*
1216          * If the IP_SENDSRCADDR control message was specified, override the
1217          * source address for this datagram.  Its use is invalidated if the
1218          * address thus specified is incomplete or clobbers other inpcbs.
1219          */
1220         laddr = inp->inp_laddr;
1221         lport = inp->inp_lport;
1222         if (src.sin_family == AF_INET) {
1223                 INP_HASH_LOCK_ASSERT(pcbinfo);
1224                 if ((lport == 0) ||
1225                     (laddr.s_addr == INADDR_ANY &&
1226                      src.sin_addr.s_addr == INADDR_ANY)) {
1227                         error = EINVAL;
1228                         goto release;
1229                 }
1230                 error = in_pcbbind_setup(inp, (struct sockaddr *)&src,
1231                     &laddr.s_addr, &lport, td->td_ucred);
1232                 if (error)
1233                         goto release;
1234         }
1235
1236         /*
1237          * If a UDP socket has been connected, then a local address/port will
1238          * have been selected and bound.
1239          *
1240          * If a UDP socket has not been connected to, then an explicit
1241          * destination address must be used, in which case a local
1242          * address/port may not have been selected and bound.
1243          */
1244         if (sin != NULL) {
1245                 INP_LOCK_ASSERT(inp);
1246                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1247                         error = EISCONN;
1248                         goto release;
1249                 }
1250
1251                 /*
1252                  * Jail may rewrite the destination address, so let it do
1253                  * that before we use it.
1254                  */
1255                 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1256                 if (error)
1257                         goto release;
1258
1259                 /*
1260                  * If a local address or port hasn't yet been selected, or if
1261                  * the destination address needs to be rewritten due to using
1262                  * a special INADDR_ constant, invoke in_pcbconnect_setup()
1263                  * to do the heavy lifting.  Once a port is selected, we
1264                  * commit the binding back to the socket; we also commit the
1265                  * binding of the address if in jail.
1266                  *
1267                  * If we already have a valid binding and we're not
1268                  * requesting a destination address rewrite, use a fast path.
1269                  */
1270                 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1271                     inp->inp_lport == 0 ||
1272                     sin->sin_addr.s_addr == INADDR_ANY ||
1273                     sin->sin_addr.s_addr == INADDR_BROADCAST) {
1274                         INP_HASH_LOCK_ASSERT(pcbinfo);
1275                         error = in_pcbconnect_setup(inp, addr, &laddr.s_addr,
1276                             &lport, &faddr.s_addr, &fport, NULL,
1277                             td->td_ucred);
1278                         if (error)
1279                                 goto release;
1280
1281                         /*
1282                          * XXXRW: Why not commit the port if the address is
1283                          * !INADDR_ANY?
1284                          */
1285                         /* Commit the local port if newly assigned. */
1286                         if (inp->inp_laddr.s_addr == INADDR_ANY &&
1287                             inp->inp_lport == 0) {
1288                                 INP_WLOCK_ASSERT(inp);
1289                                 /*
1290                                  * Remember addr if jailed, to prevent
1291                                  * rebinding.
1292                                  */
1293                                 if (prison_flag(td->td_ucred, PR_IP4))
1294                                         inp->inp_laddr = laddr;
1295                                 inp->inp_lport = lport;
1296                                 INP_HASH_WLOCK(pcbinfo);
1297                                 error = in_pcbinshash(inp);
1298                                 INP_HASH_WUNLOCK(pcbinfo);
1299                                 if (error != 0) {
1300                                         inp->inp_lport = 0;
1301                                         error = EAGAIN;
1302                                         goto release;
1303                                 }
1304                                 inp->inp_flags |= INP_ANONPORT;
1305                         }
1306                 } else {
1307                         faddr = sin->sin_addr;
1308                         fport = sin->sin_port;
1309                 }
1310         } else {
1311                 INP_LOCK_ASSERT(inp);
1312                 faddr = inp->inp_faddr;
1313                 fport = inp->inp_fport;
1314                 if (faddr.s_addr == INADDR_ANY) {
1315                         error = ENOTCONN;
1316                         goto release;
1317                 }
1318         }
1319
1320         /*
1321          * Calculate data length and get a mbuf for UDP, IP, and possible
1322          * link-layer headers.  Immediate slide the data pointer back forward
1323          * since we won't use that space at this layer.
1324          */
1325         M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1326         if (m == NULL) {
1327                 error = ENOBUFS;
1328                 goto release;
1329         }
1330         m->m_data += max_linkhdr;
1331         m->m_len -= max_linkhdr;
1332         m->m_pkthdr.len -= max_linkhdr;
1333
1334         /*
1335          * Fill in mbuf with extended UDP header and addresses and length put
1336          * into network format.
1337          */
1338         ui = mtod(m, struct udpiphdr *);
1339         bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1340         ui->ui_v = IPVERSION << 4;
1341         ui->ui_pr = pr;
1342         ui->ui_src = laddr;
1343         ui->ui_dst = faddr;
1344         ui->ui_sport = lport;
1345         ui->ui_dport = fport;
1346         ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1347         if (pr == IPPROTO_UDPLITE) {
1348                 struct udpcb *up;
1349                 uint16_t plen;
1350
1351                 up = intoudpcb(inp);
1352                 cscov = up->u_txcslen;
1353                 plen = (u_short)len + sizeof(struct udphdr);
1354                 if (cscov >= plen)
1355                         cscov = 0;
1356                 ui->ui_len = htons(plen);
1357                 ui->ui_ulen = htons(cscov);
1358                 /*
1359                  * For UDP-Lite, checksum coverage length of zero means
1360                  * the entire UDPLite packet is covered by the checksum.
1361                  */
1362                 cscov_partial = (cscov == 0) ? 0 : 1;
1363         }
1364
1365         /*
1366          * Set the Don't Fragment bit in the IP header.
1367          */
1368         if (inp->inp_flags & INP_DONTFRAG) {
1369                 struct ip *ip;
1370
1371                 ip = (struct ip *)&ui->ui_i;
1372                 ip->ip_off |= htons(IP_DF);
1373         }
1374
1375         ipflags = 0;
1376         if (inp->inp_socket->so_options & SO_DONTROUTE)
1377                 ipflags |= IP_ROUTETOIF;
1378         if (inp->inp_socket->so_options & SO_BROADCAST)
1379                 ipflags |= IP_ALLOWBROADCAST;
1380         if (inp->inp_flags & INP_ONESBCAST)
1381                 ipflags |= IP_SENDONES;
1382
1383 #ifdef MAC
1384         mac_inpcb_create_mbuf(inp, m);
1385 #endif
1386
1387         /*
1388          * Set up checksum and output datagram.
1389          */
1390         ui->ui_sum = 0;
1391         if (pr == IPPROTO_UDPLITE) {
1392                 if (inp->inp_flags & INP_ONESBCAST)
1393                         faddr.s_addr = INADDR_BROADCAST;
1394                 if (cscov_partial) {
1395                         if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1396                                 ui->ui_sum = 0xffff;
1397                 } else {
1398                         if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1399                                 ui->ui_sum = 0xffff;
1400                 }
1401         } else if (V_udp_cksum) {
1402                 if (inp->inp_flags & INP_ONESBCAST)
1403                         faddr.s_addr = INADDR_BROADCAST;
1404                 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1405                     htons((u_short)len + sizeof(struct udphdr) + pr));
1406                 m->m_pkthdr.csum_flags = CSUM_UDP;
1407                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1408         }
1409         ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1410         ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1411         ((struct ip *)ui)->ip_tos = tos;                /* XXX */
1412         UDPSTAT_INC(udps_opackets);
1413
1414         /*
1415          * Setup flowid / RSS information for outbound socket.
1416          *
1417          * Once the UDP code decides to set a flowid some other way,
1418          * this allows the flowid to be overridden by userland.
1419          */
1420         if (flowtype != M_HASHTYPE_NONE) {
1421                 m->m_pkthdr.flowid = flowid;
1422                 M_HASHTYPE_SET(m, flowtype);
1423         }
1424 #ifdef  RSS
1425         else {
1426                 uint32_t hash_val, hash_type;
1427                 /*
1428                  * Calculate an appropriate RSS hash for UDP and
1429                  * UDP Lite.
1430                  *
1431                  * The called function will take care of figuring out
1432                  * whether a 2-tuple or 4-tuple hash is required based
1433                  * on the currently configured scheme.
1434                  *
1435                  * Later later on connected socket values should be
1436                  * cached in the inpcb and reused, rather than constantly
1437                  * re-calculating it.
1438                  *
1439                  * UDP Lite is a different protocol number and will
1440                  * likely end up being hashed as a 2-tuple until
1441                  * RSS / NICs grow UDP Lite protocol awareness.
1442                  */
1443                 if (rss_proto_software_hash_v4(faddr, laddr, fport, lport,
1444                     pr, &hash_val, &hash_type) == 0) {
1445                         m->m_pkthdr.flowid = hash_val;
1446                         M_HASHTYPE_SET(m, hash_type);
1447                 }
1448         }
1449
1450         /*
1451          * Don't override with the inp cached flowid value.
1452          *
1453          * Depending upon the kind of send being done, the inp
1454          * flowid/flowtype values may actually not be appropriate
1455          * for this particular socket send.
1456          *
1457          * We should either leave the flowid at zero (which is what is
1458          * currently done) or set it to some software generated
1459          * hash value based on the packet contents.
1460          */
1461         ipflags |= IP_NODEFAULTFLOWID;
1462 #endif  /* RSS */
1463
1464         if (pr == IPPROTO_UDPLITE)
1465                 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1466         else
1467                 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1468         error = ip_output(m, inp->inp_options,
1469             INP_WLOCKED(inp) ? &inp->inp_route : NULL, ipflags,
1470             inp->inp_moptions, inp);
1471         INP_UNLOCK(inp);
1472         NET_EPOCH_EXIT(et);
1473         return (error);
1474
1475 release:
1476         INP_UNLOCK(inp);
1477         NET_EPOCH_EXIT(et);
1478         m_freem(m);
1479         return (error);
1480 }
1481
1482 static void
1483 udp_abort(struct socket *so)
1484 {
1485         struct inpcb *inp;
1486         struct inpcbinfo *pcbinfo;
1487
1488         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1489         inp = sotoinpcb(so);
1490         KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1491         INP_WLOCK(inp);
1492         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1493                 INP_HASH_WLOCK(pcbinfo);
1494                 in_pcbdisconnect(inp);
1495                 inp->inp_laddr.s_addr = INADDR_ANY;
1496                 INP_HASH_WUNLOCK(pcbinfo);
1497                 soisdisconnected(so);
1498         }
1499         INP_WUNLOCK(inp);
1500 }
1501
1502 static int
1503 udp_attach(struct socket *so, int proto, struct thread *td)
1504 {
1505         static uint32_t udp_flowid;
1506         struct inpcb *inp;
1507         struct inpcbinfo *pcbinfo;
1508         int error;
1509
1510         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1511         inp = sotoinpcb(so);
1512         KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1513         error = soreserve(so, udp_sendspace, udp_recvspace);
1514         if (error)
1515                 return (error);
1516         INP_INFO_WLOCK(pcbinfo);
1517         error = in_pcballoc(so, pcbinfo);
1518         if (error) {
1519                 INP_INFO_WUNLOCK(pcbinfo);
1520                 return (error);
1521         }
1522
1523         inp = sotoinpcb(so);
1524         inp->inp_vflag |= INP_IPV4;
1525         inp->inp_ip_ttl = V_ip_defttl;
1526         inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1527         inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1528
1529         error = udp_newudpcb(inp);
1530         if (error) {
1531                 in_pcbdetach(inp);
1532                 in_pcbfree(inp);
1533                 INP_INFO_WUNLOCK(pcbinfo);
1534                 return (error);
1535         }
1536
1537         INP_WUNLOCK(inp);
1538         INP_INFO_WUNLOCK(pcbinfo);
1539         return (0);
1540 }
1541 #endif /* INET */
1542
1543 int
1544 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1545 {
1546         struct inpcb *inp;
1547         struct udpcb *up;
1548
1549         KASSERT(so->so_type == SOCK_DGRAM,
1550             ("udp_set_kernel_tunneling: !dgram"));
1551         inp = sotoinpcb(so);
1552         KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1553         INP_WLOCK(inp);
1554         up = intoudpcb(inp);
1555         if ((up->u_tun_func != NULL) ||
1556             (up->u_icmp_func != NULL)) {
1557                 INP_WUNLOCK(inp);
1558                 return (EBUSY);
1559         }
1560         up->u_tun_func = f;
1561         up->u_icmp_func = i;
1562         up->u_tun_ctx = ctx;
1563         INP_WUNLOCK(inp);
1564         return (0);
1565 }
1566
1567 #ifdef INET
1568 static int
1569 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1570 {
1571         struct inpcb *inp;
1572         struct inpcbinfo *pcbinfo;
1573         int error;
1574
1575         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1576         inp = sotoinpcb(so);
1577         KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1578         INP_WLOCK(inp);
1579         INP_HASH_WLOCK(pcbinfo);
1580         error = in_pcbbind(inp, nam, td->td_ucred);
1581         INP_HASH_WUNLOCK(pcbinfo);
1582         INP_WUNLOCK(inp);
1583         return (error);
1584 }
1585
1586 static void
1587 udp_close(struct socket *so)
1588 {
1589         struct inpcb *inp;
1590         struct inpcbinfo *pcbinfo;
1591
1592         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1593         inp = sotoinpcb(so);
1594         KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1595         INP_WLOCK(inp);
1596         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1597                 INP_HASH_WLOCK(pcbinfo);
1598                 in_pcbdisconnect(inp);
1599                 inp->inp_laddr.s_addr = INADDR_ANY;
1600                 INP_HASH_WUNLOCK(pcbinfo);
1601                 soisdisconnected(so);
1602         }
1603         INP_WUNLOCK(inp);
1604 }
1605
1606 static int
1607 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1608 {
1609         struct inpcb *inp;
1610         struct inpcbinfo *pcbinfo;
1611         struct sockaddr_in *sin;
1612         int error;
1613
1614         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1615         inp = sotoinpcb(so);
1616         KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1617         INP_WLOCK(inp);
1618         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1619                 INP_WUNLOCK(inp);
1620                 return (EISCONN);
1621         }
1622         sin = (struct sockaddr_in *)nam;
1623         error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1624         if (error != 0) {
1625                 INP_WUNLOCK(inp);
1626                 return (error);
1627         }
1628         INP_HASH_WLOCK(pcbinfo);
1629         error = in_pcbconnect(inp, nam, td->td_ucred);
1630         INP_HASH_WUNLOCK(pcbinfo);
1631         if (error == 0)
1632                 soisconnected(so);
1633         INP_WUNLOCK(inp);
1634         return (error);
1635 }
1636
1637 static void
1638 udp_detach(struct socket *so)
1639 {
1640         struct inpcb *inp;
1641         struct inpcbinfo *pcbinfo;
1642         struct udpcb *up;
1643
1644         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1645         inp = sotoinpcb(so);
1646         KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1647         KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1648             ("udp_detach: not disconnected"));
1649         INP_INFO_WLOCK(pcbinfo);
1650         INP_WLOCK(inp);
1651         up = intoudpcb(inp);
1652         KASSERT(up != NULL, ("%s: up == NULL", __func__));
1653         inp->inp_ppcb = NULL;
1654         in_pcbdetach(inp);
1655         in_pcbfree(inp);
1656         INP_INFO_WUNLOCK(pcbinfo);
1657         udp_discardcb(up);
1658 }
1659
1660 static int
1661 udp_disconnect(struct socket *so)
1662 {
1663         struct inpcb *inp;
1664         struct inpcbinfo *pcbinfo;
1665
1666         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1667         inp = sotoinpcb(so);
1668         KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1669         INP_WLOCK(inp);
1670         if (inp->inp_faddr.s_addr == INADDR_ANY) {
1671                 INP_WUNLOCK(inp);
1672                 return (ENOTCONN);
1673         }
1674         INP_HASH_WLOCK(pcbinfo);
1675         in_pcbdisconnect(inp);
1676         inp->inp_laddr.s_addr = INADDR_ANY;
1677         INP_HASH_WUNLOCK(pcbinfo);
1678         SOCK_LOCK(so);
1679         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1680         SOCK_UNLOCK(so);
1681         INP_WUNLOCK(inp);
1682         return (0);
1683 }
1684
1685 static int
1686 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1687     struct mbuf *control, struct thread *td)
1688 {
1689         struct inpcb *inp;
1690
1691         inp = sotoinpcb(so);
1692         KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1693         return (udp_output(inp, m, addr, control, td));
1694 }
1695 #endif /* INET */
1696
1697 int
1698 udp_shutdown(struct socket *so)
1699 {
1700         struct inpcb *inp;
1701
1702         inp = sotoinpcb(so);
1703         KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1704         INP_WLOCK(inp);
1705         socantsendmore(so);
1706         INP_WUNLOCK(inp);
1707         return (0);
1708 }
1709
1710 #ifdef INET
1711 struct pr_usrreqs udp_usrreqs = {
1712         .pru_abort =            udp_abort,
1713         .pru_attach =           udp_attach,
1714         .pru_bind =             udp_bind,
1715         .pru_connect =          udp_connect,
1716         .pru_control =          in_control,
1717         .pru_detach =           udp_detach,
1718         .pru_disconnect =       udp_disconnect,
1719         .pru_peeraddr =         in_getpeeraddr,
1720         .pru_send =             udp_send,
1721         .pru_soreceive =        soreceive_dgram,
1722         .pru_sosend =           sosend_dgram,
1723         .pru_shutdown =         udp_shutdown,
1724         .pru_sockaddr =         in_getsockaddr,
1725         .pru_sosetlabel =       in_pcbsosetlabel,
1726         .pru_close =            udp_close,
1727 };
1728 #endif /* INET */