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 #include "opt_inet.h"
  43 #include "opt_inet6.h"
  44 #include "opt_ipsec.h"
  45 #include "opt_route.h"
  46 #include "opt_rss.h"
  47
  48 #include <sys/param.h>
  49 #include <sys/domain.h>
  50 #include <sys/eventhandler.h>
  51 #include <sys/jail.h>
  52 #include <sys/kernel.h>
  53 #include <sys/lock.h>
  54 #include <sys/malloc.h>
  55 #include <sys/mbuf.h>
  56 #include <sys/priv.h>
  57 #include <sys/proc.h>
  58 #include <sys/protosw.h>
  59 #include <sys/sdt.h>
  60 #include <sys/signalvar.h>
  61 #include <sys/socket.h>
  62 #include <sys/socketvar.h>
  63 #include <sys/sx.h>
  64 #include <sys/sysctl.h>
  65 #include <sys/syslog.h>
  66 #include <sys/systm.h>
  67
  68 #include <vm/uma.h>
  69
  70 #include <net/if.h>
  71 #include <net/if_var.h>
  72 #include <net/route.h>
  73 #include <net/route/nhop.h>
  74 #include <net/rss_config.h>
  75
  76 #include <netinet/in.h>
  77 #include <netinet/in_kdtrace.h>
  78 #include <netinet/in_fib.h>
  79 #include <netinet/in_pcb.h>
  80 #include <netinet/in_systm.h>
  81 #include <netinet/in_var.h>
  82 #include <netinet/ip.h>
  83 #ifdef INET6
  84 #include <netinet/ip6.h>
  85 #endif
  86 #include <netinet/ip_icmp.h>
  87 #include <netinet/icmp_var.h>
  88 #include <netinet/ip_var.h>
  89 #include <netinet/ip_options.h>
  90 #ifdef INET6
  91 #include <netinet6/ip6_var.h>
  92 #endif
  93 #include <netinet/udp.h>
  94 #include <netinet/udp_var.h>
  95 #include <netinet/udplite.h>
  96 #include <netinet/in_rss.h>
  97
  98 #include <netipsec/ipsec_support.h>
  99
 100 #include <machine/in_cksum.h>
 101
 102 #include <security/mac/mac_framework.h>
 103
 104 /*
 105  * UDP and UDP-Lite protocols implementation.
 106  * Per RFC 768, August, 1980.
 107  * Per RFC 3828, July, 2004.
 108  */
 109
 110 /*
 111  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
 112  * removes the only data integrity mechanism for packets and malformed
 113  * packets that would otherwise be discarded due to bad checksums, and may
 114  * cause problems (especially for NFS data blocks).
 115  */
 116 VNET_DEFINE(int, udp_cksum) = 1;
 117 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
 118     &VNET_NAME(udp_cksum), 0, "compute udp checksum");
 119
 120 VNET_DEFINE(int, udp_log_in_vain) = 0;
 121 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW,
 122     &VNET_NAME(udp_log_in_vain), 0, "Log all incoming UDP packets");
 123
 124 VNET_DEFINE(int, udp_blackhole) = 0;
 125 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
 126     &VNET_NAME(udp_blackhole), 0,
 127     "Do not send port unreachables for refused connects");
 128 VNET_DEFINE(bool, udp_blackhole_local) = false;
 129 SYSCTL_BOOL(_net_inet_udp, OID_AUTO, blackhole_local, CTLFLAG_VNET |
 130     CTLFLAG_RW, &VNET_NAME(udp_blackhole_local), false,
 131     "Enforce net.inet.udp.blackhole for locally originated packets");
 132
 133 u_long  udp_sendspace = 9216;           /* really max datagram size */
 134 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
 135     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
 136
 137 u_long  udp_recvspace = 40 * (1024 +
 138 #ifdef INET6
 139                                       sizeof(struct sockaddr_in6)
 140 #else
 141                                       sizeof(struct sockaddr_in)
 142 #endif
 143                                       );        /* 40 1K datagrams */
 144
 145 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
 146     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
 147
 148 VNET_DEFINE(struct inpcbinfo, udbinfo);
 149 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
 150
 151 #ifndef UDBHASHSIZE
 152 #define UDBHASHSIZE     128
 153 #endif
 154
 155 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat);          /* from udp_var.h */
 156 VNET_PCPUSTAT_SYSINIT(udpstat);
 157 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
 158     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
 159
 160 #ifdef VIMAGE
 161 VNET_PCPUSTAT_SYSUNINIT(udpstat);
 162 #endif /* VIMAGE */
 163 #ifdef INET
 164 static void     udp_detach(struct socket *so);
 165 #endif
 166
 167 INPCBSTORAGE_DEFINE(udpcbstor, udpcb, "udpinp", "udp_inpcb", "udp", "udphash");
 168 INPCBSTORAGE_DEFINE(udplitecbstor, udpcb, "udpliteinp", "udplite_inpcb",
 169     "udplite", "udplitehash");
 170
 171 static void
 172 udp_vnet_init(void *arg __unused)
 173 {
 174
 175         /*
 176          * For now default to 2-tuple UDP hashing - until the fragment
 177          * reassembly code can also update the flowid.
 178          *
 179          * Once we can calculate the flowid that way and re-establish
 180          * a 4-tuple, flip this to 4-tuple.
 181          */
 182         in_pcbinfo_init(&V_udbinfo, &udpcbstor, UDBHASHSIZE, UDBHASHSIZE);
 183         /* Additional pcbinfo for UDP-Lite */
 184         in_pcbinfo_init(&V_ulitecbinfo, &udplitecbstor, UDBHASHSIZE,
 185             UDBHASHSIZE);
 186 }
 187 VNET_SYSINIT(udp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
 188     udp_vnet_init, NULL);
 189
 190 /*
 191  * Kernel module interface for updating udpstat.  The argument is an index
 192  * into udpstat treated as an array of u_long.  While this encodes the
 193  * general layout of udpstat into the caller, it doesn't encode its location,
 194  * so that future changes to add, for example, per-CPU stats support won't
 195  * cause binary compatibility problems for kernel modules.
 196  */
 197 void
 198 kmod_udpstat_inc(int statnum)
 199 {
 200
 201         counter_u64_add(VNET(udpstat)[statnum], 1);
 202 }
 203
 204 #ifdef VIMAGE
 205 static void
 206 udp_destroy(void *unused __unused)
 207 {
 208
 209         in_pcbinfo_destroy(&V_udbinfo);
 210         in_pcbinfo_destroy(&V_ulitecbinfo);
 211 }
 212 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
 213 #endif
 214
 215 #ifdef INET
 216 /*
 217  * Subroutine of udp_input(), which appends the provided mbuf chain to the
 218  * passed pcb/socket.  The caller must provide a sockaddr_in via udp_in that
 219  * contains the source address.  If the socket ends up being an IPv6 socket,
 220  * udp_append() will convert to a sockaddr_in6 before passing the address
 221  * into the socket code.
 222  *
 223  * In the normal case udp_append() will return 0, indicating that you
 224  * must unlock the inp. However if a tunneling protocol is in place we increment
 225  * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
 226  * then decrement the reference count. If the inp_rele returns 1, indicating the
 227  * inp is gone, we return that to the caller to tell them *not* to unlock
 228  * the inp. In the case of multi-cast this will cause the distribution
 229  * to stop (though most tunneling protocols known currently do *not* use
 230  * multicast).
 231  */
 232 static int
 233 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
 234     struct sockaddr_in *udp_in)
 235 {
 236         struct sockaddr *append_sa;
 237         struct socket *so;
 238         struct mbuf *tmpopts, *opts = NULL;
 239 #ifdef INET6
 240         struct sockaddr_in6 udp_in6;
 241 #endif
 242         struct udpcb *up;
 243         bool filtered;
 244
 245         INP_LOCK_ASSERT(inp);
 246
 247         /*
 248          * Engage the tunneling protocol.
 249          */
 250         up = intoudpcb(inp);
 251         if (up->u_tun_func != NULL) {
 252                 in_pcbref(inp);
 253                 INP_RUNLOCK(inp);
 254                 filtered = (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
 255                     up->u_tun_ctx);
 256                 INP_RLOCK(inp);
 257                 if (filtered)
 258                         return (in_pcbrele_rlocked(inp));
 259         }
 260
 261         off += sizeof(struct udphdr);
 262
 263 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 264         /* Check AH/ESP integrity. */
 265         if (IPSEC_ENABLED(ipv4) &&
 266             IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
 267                 m_freem(n);
 268                 return (0);
 269         }
 270         if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
 271                 if (IPSEC_ENABLED(ipv4) &&
 272                     UDPENCAP_INPUT(n, off, AF_INET) != 0)
 273                         return (0);     /* Consumed. */
 274         }
 275 #endif /* IPSEC */
 276 #ifdef MAC
 277         if (mac_inpcb_check_deliver(inp, n) != 0) {
 278                 m_freem(n);
 279                 return (0);
 280         }
 281 #endif /* MAC */
 282         if (inp->inp_flags & INP_CONTROLOPTS ||
 283             inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
 284 #ifdef INET6
 285                 if (inp->inp_vflag & INP_IPV6)
 286                         (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
 287                 else
 288 #endif /* INET6 */
 289                         ip_savecontrol(inp, &opts, ip, n);
 290         }
 291         if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
 292                 tmpopts = sbcreatecontrol(&udp_in[1],
 293                     sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP,
 294                     M_NOWAIT);
 295                 if (tmpopts) {
 296                         if (opts) {
 297                                 tmpopts->m_next = opts;
 298                                 opts = tmpopts;
 299                         } else
 300                                 opts = tmpopts;
 301                 }
 302         }
 303 #ifdef INET6
 304         if (inp->inp_vflag & INP_IPV6) {
 305                 bzero(&udp_in6, sizeof(udp_in6));
 306                 udp_in6.sin6_len = sizeof(udp_in6);
 307                 udp_in6.sin6_family = AF_INET6;
 308                 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
 309                 append_sa = (struct sockaddr *)&udp_in6;
 310         } else
 311 #endif /* INET6 */
 312                 append_sa = (struct sockaddr *)&udp_in[0];
 313         m_adj(n, off);
 314
 315         so = inp->inp_socket;
 316         SOCKBUF_LOCK(&so->so_rcv);
 317         if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
 318                 soroverflow_locked(so);
 319                 m_freem(n);
 320                 if (opts)
 321                         m_freem(opts);
 322                 UDPSTAT_INC(udps_fullsock);
 323         } else
 324                 sorwakeup_locked(so);
 325         return (0);
 326 }
 327
 328 static bool
 329 udp_multi_match(const struct inpcb *inp, void *v)
 330 {
 331         struct ip *ip = v;
 332         struct udphdr *uh = (struct udphdr *)(ip + 1);
 333
 334         if (inp->inp_lport != uh->uh_dport)
 335                 return (false);
 336 #ifdef INET6
 337         if ((inp->inp_vflag & INP_IPV4) == 0)
 338                 return (false);
 339 #endif
 340         if (inp->inp_laddr.s_addr != INADDR_ANY &&
 341             inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
 342                 return (false);
 343         if (inp->inp_faddr.s_addr != INADDR_ANY &&
 344             inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 345                 return (false);
 346         if (inp->inp_fport != 0 &&
 347             inp->inp_fport != uh->uh_sport)
 348                 return (false);
 349
 350         return (true);
 351 }
 352
 353 static int
 354 udp_multi_input(struct mbuf *m, int proto, struct sockaddr_in *udp_in)
 355 {
 356         struct ip *ip = mtod(m, struct ip *);
 357         struct inpcb_iterator inpi = INP_ITERATOR(udp_get_inpcbinfo(proto),
 358             INPLOOKUP_RLOCKPCB, udp_multi_match, ip);
 359 #ifdef KDTRACE_HOOKS
 360         struct udphdr *uh = (struct udphdr *)(ip + 1);
 361 #endif
 362         struct inpcb *inp;
 363         struct mbuf *n;
 364         int appends = 0;
 365
 366         MPASS(ip->ip_hl == sizeof(struct ip) >> 2);
 367
 368         while ((inp = inp_next(&inpi)) != NULL) {
 369                 /*
 370                  * XXXRW: Because we weren't holding either the inpcb
 371                  * or the hash lock when we checked for a match
 372                  * before, we should probably recheck now that the
 373                  * inpcb lock is held.
 374                  */
 375                 /*
 376                  * Handle socket delivery policy for any-source
 377                  * and source-specific multicast. [RFC3678]
 378                  */
 379                 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 380                         struct ip_moptions      *imo;
 381                         struct sockaddr_in       group;
 382                         int                      blocked;
 383
 384                         imo = inp->inp_moptions;
 385                         if (imo == NULL)
 386                                 continue;
 387                         bzero(&group, sizeof(struct sockaddr_in));
 388                         group.sin_len = sizeof(struct sockaddr_in);
 389                         group.sin_family = AF_INET;
 390                         group.sin_addr = ip->ip_dst;
 391
 392                         blocked = imo_multi_filter(imo, m->m_pkthdr.rcvif,
 393                                 (struct sockaddr *)&group,
 394                                 (struct sockaddr *)&udp_in[0]);
 395                         if (blocked != MCAST_PASS) {
 396                                 if (blocked == MCAST_NOTGMEMBER)
 397                                         IPSTAT_INC(ips_notmember);
 398                                 if (blocked == MCAST_NOTSMEMBER ||
 399                                     blocked == MCAST_MUTED)
 400                                         UDPSTAT_INC(udps_filtermcast);
 401                                 continue;
 402                         }
 403                 }
 404                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
 405                         if (proto == IPPROTO_UDPLITE)
 406                                 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 407                         else
 408                                 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 409                         if (udp_append(inp, ip, n, sizeof(struct ip), udp_in)) {
 410                                 break;
 411                         } else
 412                                 appends++;
 413                 }
 414                 /*
 415                  * Don't look for additional matches if this one does
 416                  * not have either the SO_REUSEPORT or SO_REUSEADDR
 417                  * socket options set.  This heuristic avoids
 418                  * searching through all pcbs in the common case of a
 419                  * non-shared port.  It assumes that an application
 420                  * will never clear these options after setting them.
 421                  */
 422                 if ((inp->inp_socket->so_options &
 423                     (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) {
 424                         INP_RUNLOCK(inp);
 425                         break;
 426                 }
 427         }
 428
 429         if (appends == 0) {
 430                 /*
 431                  * No matching pcb found; discard datagram.  (No need
 432                  * to send an ICMP Port Unreachable for a broadcast
 433                  * or multicast datgram.)
 434                  */
 435                 UDPSTAT_INC(udps_noport);
 436                 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
 437                         UDPSTAT_INC(udps_noportmcast);
 438                 else
 439                         UDPSTAT_INC(udps_noportbcast);
 440         }
 441         m_freem(m);
 442
 443         return (IPPROTO_DONE);
 444 }
 445
 446 static int
 447 udp_input(struct mbuf **mp, int *offp, int proto)
 448 {
 449         struct ip *ip;
 450         struct udphdr *uh;
 451         struct ifnet *ifp;
 452         struct inpcb *inp;
 453         uint16_t len, ip_len;
 454         struct inpcbinfo *pcbinfo;
 455         struct sockaddr_in udp_in[2];
 456         struct mbuf *m;
 457         struct m_tag *fwd_tag;
 458         int cscov_partial, iphlen;
 459
 460         m = *mp;
 461         iphlen = *offp;
 462         ifp = m->m_pkthdr.rcvif;
 463         *mp = NULL;
 464         UDPSTAT_INC(udps_ipackets);
 465
 466         /*
 467          * Strip IP options, if any; should skip this, make available to
 468          * user, and use on returned packets, but we don't yet have a way to
 469          * check the checksum with options still present.
 470          */
 471         if (iphlen > sizeof (struct ip)) {
 472                 ip_stripoptions(m);
 473                 iphlen = sizeof(struct ip);
 474         }
 475
 476         /*
 477          * Get IP and UDP header together in first mbuf.
 478          */
 479         if (m->m_len < iphlen + sizeof(struct udphdr)) {
 480                 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
 481                         UDPSTAT_INC(udps_hdrops);
 482                         return (IPPROTO_DONE);
 483                 }
 484         }
 485         ip = mtod(m, struct ip *);
 486         uh = (struct udphdr *)((caddr_t)ip + iphlen);
 487         cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
 488
 489         /*
 490          * Destination port of 0 is illegal, based on RFC768.
 491          */
 492         if (uh->uh_dport == 0)
 493                 goto badunlocked;
 494
 495         /*
 496          * Construct sockaddr format source address.  Stuff source address
 497          * and datagram in user buffer.
 498          */
 499         bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
 500         udp_in[0].sin_len = sizeof(struct sockaddr_in);
 501         udp_in[0].sin_family = AF_INET;
 502         udp_in[0].sin_port = uh->uh_sport;
 503         udp_in[0].sin_addr = ip->ip_src;
 504         udp_in[1].sin_len = sizeof(struct sockaddr_in);
 505         udp_in[1].sin_family = AF_INET;
 506         udp_in[1].sin_port = uh->uh_dport;
 507         udp_in[1].sin_addr = ip->ip_dst;
 508
 509         /*
 510          * Make mbuf data length reflect UDP length.  If not enough data to
 511          * reflect UDP length, drop.
 512          */
 513         len = ntohs((u_short)uh->uh_ulen);
 514         ip_len = ntohs(ip->ip_len) - iphlen;
 515         if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
 516                 /* Zero means checksum over the complete packet. */
 517                 if (len == 0)
 518                         len = ip_len;
 519                 cscov_partial = 0;
 520         }
 521         if (ip_len != len) {
 522                 if (len > ip_len || len < sizeof(struct udphdr)) {
 523                         UDPSTAT_INC(udps_badlen);
 524                         goto badunlocked;
 525                 }
 526                 if (proto == IPPROTO_UDP)
 527                         m_adj(m, len - ip_len);
 528         }
 529
 530         /*
 531          * Checksum extended UDP header and data.
 532          */
 533         if (uh->uh_sum) {
 534                 u_short uh_sum;
 535
 536                 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
 537                     !cscov_partial) {
 538                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 539                                 uh_sum = m->m_pkthdr.csum_data;
 540                         else
 541                                 uh_sum = in_pseudo(ip->ip_src.s_addr,
 542                                     ip->ip_dst.s_addr, htonl((u_short)len +
 543                                     m->m_pkthdr.csum_data + proto));
 544                         uh_sum ^= 0xffff;
 545                 } else {
 546                         char b[offsetof(struct ipovly, ih_src)];
 547                         struct ipovly *ipov = (struct ipovly *)ip;
 548
 549                         bcopy(ipov, b, sizeof(b));
 550                         bzero(ipov, sizeof(ipov->ih_x1));
 551                         ipov->ih_len = (proto == IPPROTO_UDP) ?
 552                             uh->uh_ulen : htons(ip_len);
 553                         uh_sum = in_cksum(m, len + sizeof (struct ip));
 554                         bcopy(b, ipov, sizeof(b));
 555                 }
 556                 if (uh_sum) {
 557                         UDPSTAT_INC(udps_badsum);
 558                         m_freem(m);
 559                         return (IPPROTO_DONE);
 560                 }
 561         } else {
 562                 if (proto == IPPROTO_UDP) {
 563                         UDPSTAT_INC(udps_nosum);
 564                 } else {
 565                         /* UDPLite requires a checksum */
 566                         /* XXX: What is the right UDPLite MIB counter here? */
 567                         m_freem(m);
 568                         return (IPPROTO_DONE);
 569                 }
 570         }
 571
 572         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
 573             in_broadcast(ip->ip_dst, ifp))
 574                 return (udp_multi_input(m, proto, udp_in));
 575
 576         pcbinfo = udp_get_inpcbinfo(proto);
 577
 578         /*
 579          * Locate pcb for datagram.
 580          *
 581          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 582          */
 583         if ((m->m_flags & M_IP_NEXTHOP) &&
 584             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 585                 struct sockaddr_in *next_hop;
 586
 587                 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
 588
 589                 /*
 590                  * Transparently forwarded. Pretend to be the destination.
 591                  * Already got one like this?
 592                  */
 593                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 594                     ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
 595                 if (!inp) {
 596                         /*
 597                          * It's new.  Try to find the ambushing socket.
 598                          * Because we've rewritten the destination address,
 599                          * any hardware-generated hash is ignored.
 600                          */
 601                         inp = in_pcblookup(pcbinfo, ip->ip_src,
 602                             uh->uh_sport, next_hop->sin_addr,
 603                             next_hop->sin_port ? htons(next_hop->sin_port) :
 604                             uh->uh_dport, INPLOOKUP_WILDCARD |
 605                             INPLOOKUP_RLOCKPCB, ifp);
 606                 }
 607                 /* Remove the tag from the packet. We don't need it anymore. */
 608                 m_tag_delete(m, fwd_tag);
 609                 m->m_flags &= ~M_IP_NEXTHOP;
 610         } else
 611                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 612                     ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
 613                     INPLOOKUP_RLOCKPCB, ifp, m);
 614         if (inp == NULL) {
 615                 if (V_udp_log_in_vain) {
 616                         char src[INET_ADDRSTRLEN];
 617                         char dst[INET_ADDRSTRLEN];
 618
 619                         log(LOG_INFO,
 620                             "Connection attempt to UDP %s:%d from %s:%d\n",
 621                             inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
 622                             inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
 623                 }
 624                 if (proto == IPPROTO_UDPLITE)
 625                         UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
 626                 else
 627                         UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
 628                 UDPSTAT_INC(udps_noport);
 629                 if (m->m_flags & (M_BCAST | M_MCAST)) {
 630                         UDPSTAT_INC(udps_noportbcast);
 631                         goto badunlocked;
 632                 }
 633                 if (V_udp_blackhole && (V_udp_blackhole_local ||
 634                     !in_localip(ip->ip_src)))
 635                         goto badunlocked;
 636                 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
 637                         goto badunlocked;
 638                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
 639                 return (IPPROTO_DONE);
 640         }
 641
 642         /*
 643          * Check the minimum TTL for socket.
 644          */
 645         INP_RLOCK_ASSERT(inp);
 646         if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
 647                 if (proto == IPPROTO_UDPLITE)
 648                         UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 649                 else
 650                         UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 651                 INP_RUNLOCK(inp);
 652                 m_freem(m);
 653                 return (IPPROTO_DONE);
 654         }
 655         if (cscov_partial) {
 656                 struct udpcb *up;
 657
 658                 up = intoudpcb(inp);
 659                 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
 660                         INP_RUNLOCK(inp);
 661                         m_freem(m);
 662                         return (IPPROTO_DONE);
 663                 }
 664         }
 665
 666         if (proto == IPPROTO_UDPLITE)
 667                 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 668         else
 669                 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 670         if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
 671                 INP_RUNLOCK(inp);
 672         return (IPPROTO_DONE);
 673
 674 badunlocked:
 675         m_freem(m);
 676         return (IPPROTO_DONE);
 677 }
 678 #endif /* INET */
 679
 680 /*
 681  * Notify a udp user of an asynchronous error; just wake up so that they can
 682  * collect error status.
 683  */
 684 struct inpcb *
 685 udp_notify(struct inpcb *inp, int errno)
 686 {
 687
 688         INP_WLOCK_ASSERT(inp);
 689         if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
 690              errno == EHOSTDOWN) && inp->inp_route.ro_nh) {
 691                 NH_FREE(inp->inp_route.ro_nh);
 692                 inp->inp_route.ro_nh = (struct nhop_object *)NULL;
 693         }
 694
 695         inp->inp_socket->so_error = errno;
 696         sorwakeup(inp->inp_socket);
 697         sowwakeup(inp->inp_socket);
 698         return (inp);
 699 }
 700
 701 #ifdef INET
 702 static void
 703 udp_common_ctlinput(struct icmp *icmp, struct inpcbinfo *pcbinfo)
 704 {
 705         struct ip *ip = &icmp->icmp_ip;
 706         struct udphdr *uh;
 707         struct inpcb *inp;
 708
 709         if (icmp_errmap(icmp) == 0)
 710                 return;
 711
 712         uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 713         inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport, ip->ip_src,
 714             uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
 715         if (inp != NULL) {
 716                 INP_WLOCK_ASSERT(inp);
 717                 if (inp->inp_socket != NULL)
 718                         udp_notify(inp, icmp_errmap(icmp));
 719                 INP_WUNLOCK(inp);
 720         } else {
 721                 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport,
 722                     ip->ip_src, uh->uh_sport,
 723                     INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 724                 if (inp != NULL) {
 725                         struct udpcb *up;
 726                         udp_tun_icmp_t *func;
 727
 728                         up = intoudpcb(inp);
 729                         func = up->u_icmp_func;
 730                         INP_RUNLOCK(inp);
 731                         if (func != NULL)
 732                                 func(icmp);
 733                 }
 734         }
 735 }
 736
 737 static void
 738 udp_ctlinput(struct icmp *icmp)
 739 {
 740
 741         return (udp_common_ctlinput(icmp, &V_udbinfo));
 742 }
 743
 744 static void
 745 udplite_ctlinput(struct icmp *icmp)
 746 {
 747
 748         return (udp_common_ctlinput(icmp, &V_ulitecbinfo));
 749 }
 750 #endif /* INET */
 751
 752 static int
 753 udp_pcblist(SYSCTL_HANDLER_ARGS)
 754 {
 755         struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_udbinfo,
 756             INPLOOKUP_RLOCKPCB);
 757         struct xinpgen xig;
 758         struct inpcb *inp;
 759         int error;
 760
 761         if (req->newptr != 0)
 762                 return (EPERM);
 763
 764         if (req->oldptr == 0) {
 765                 int n;
 766
 767                 n = V_udbinfo.ipi_count;
 768                 n += imax(n / 8, 10);
 769                 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
 770                 return (0);
 771         }
 772
 773         if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
 774                 return (error);
 775
 776         bzero(&xig, sizeof(xig));
 777         xig.xig_len = sizeof xig;
 778         xig.xig_count = V_udbinfo.ipi_count;
 779         xig.xig_gen = V_udbinfo.ipi_gencnt;
 780         xig.xig_sogen = so_gencnt;
 781         error = SYSCTL_OUT(req, &xig, sizeof xig);
 782         if (error)
 783                 return (error);
 784
 785         while ((inp = inp_next(&inpi)) != NULL) {
 786                 if (inp->inp_gencnt <= xig.xig_gen &&
 787                     cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
 788                         struct xinpcb xi;
 789
 790                         in_pcbtoxinpcb(inp, &xi);
 791                         error = SYSCTL_OUT(req, &xi, sizeof xi);
 792                         if (error) {
 793                                 INP_RUNLOCK(inp);
 794                                 break;
 795                         }
 796                 }
 797         }
 798
 799         if (!error) {
 800                 /*
 801                  * Give the user an updated idea of our state.  If the
 802                  * generation differs from what we told her before, she knows
 803                  * that something happened while we were processing this
 804                  * request, and it might be necessary to retry.
 805                  */
 806                 xig.xig_gen = V_udbinfo.ipi_gencnt;
 807                 xig.xig_sogen = so_gencnt;
 808                 xig.xig_count = V_udbinfo.ipi_count;
 809                 error = SYSCTL_OUT(req, &xig, sizeof xig);
 810         }
 811
 812         return (error);
 813 }
 814
 815 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
 816     CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
 817     udp_pcblist, "S,xinpcb",
 818     "List of active UDP sockets");
 819
 820 #ifdef INET
 821 static int
 822 udp_getcred(SYSCTL_HANDLER_ARGS)
 823 {
 824         struct xucred xuc;
 825         struct sockaddr_in addrs[2];
 826         struct epoch_tracker et;
 827         struct inpcb *inp;
 828         int error;
 829
 830         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 831         if (error)
 832                 return (error);
 833         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 834         if (error)
 835                 return (error);
 836         NET_EPOCH_ENTER(et);
 837         inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
 838             addrs[0].sin_addr, addrs[0].sin_port,
 839             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 840         NET_EPOCH_EXIT(et);
 841         if (inp != NULL) {
 842                 INP_RLOCK_ASSERT(inp);
 843                 if (inp->inp_socket == NULL)
 844                         error = ENOENT;
 845                 if (error == 0)
 846                         error = cr_canseeinpcb(req->td->td_ucred, inp);
 847                 if (error == 0)
 848                         cru2x(inp->inp_cred, &xuc);
 849                 INP_RUNLOCK(inp);
 850         } else
 851                 error = ENOENT;
 852         if (error == 0)
 853                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 854         return (error);
 855 }
 856
 857 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
 858     CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
 859     0, 0, udp_getcred, "S,xucred",
 860     "Get the xucred of a UDP connection");
 861 #endif /* INET */
 862
 863 int
 864 udp_ctloutput(struct socket *so, struct sockopt *sopt)
 865 {
 866         struct inpcb *inp;
 867         struct udpcb *up;
 868         int isudplite, error, optval;
 869
 870         error = 0;
 871         isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
 872         inp = sotoinpcb(so);
 873         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 874         INP_WLOCK(inp);
 875         if (sopt->sopt_level != so->so_proto->pr_protocol) {
 876 #ifdef INET6
 877                 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
 878                         INP_WUNLOCK(inp);
 879                         error = ip6_ctloutput(so, sopt);
 880                 }
 881 #endif
 882 #if defined(INET) && defined(INET6)
 883                 else
 884 #endif
 885 #ifdef INET
 886                 {
 887                         INP_WUNLOCK(inp);
 888                         error = ip_ctloutput(so, sopt);
 889                 }
 890 #endif
 891                 return (error);
 892         }
 893
 894         switch (sopt->sopt_dir) {
 895         case SOPT_SET:
 896                 switch (sopt->sopt_name) {
 897 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 898 #ifdef INET
 899                 case UDP_ENCAP:
 900                         if (!IPSEC_ENABLED(ipv4)) {
 901                                 INP_WUNLOCK(inp);
 902                                 return (ENOPROTOOPT);
 903                         }
 904                         error = UDPENCAP_PCBCTL(inp, sopt);
 905                         break;
 906 #endif /* INET */
 907 #endif /* IPSEC */
 908                 case UDPLITE_SEND_CSCOV:
 909                 case UDPLITE_RECV_CSCOV:
 910                         if (!isudplite) {
 911                                 INP_WUNLOCK(inp);
 912                                 error = ENOPROTOOPT;
 913                                 break;
 914                         }
 915                         INP_WUNLOCK(inp);
 916                         error = sooptcopyin(sopt, &optval, sizeof(optval),
 917                             sizeof(optval));
 918                         if (error != 0)
 919                                 break;
 920                         inp = sotoinpcb(so);
 921                         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 922                         INP_WLOCK(inp);
 923                         up = intoudpcb(inp);
 924                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
 925                         if ((optval != 0 && optval < 8) || (optval > 65535)) {
 926                                 INP_WUNLOCK(inp);
 927                                 error = EINVAL;
 928                                 break;
 929                         }
 930                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
 931                                 up->u_txcslen = optval;
 932                         else
 933                                 up->u_rxcslen = optval;
 934                         INP_WUNLOCK(inp);
 935                         break;
 936                 default:
 937                         INP_WUNLOCK(inp);
 938                         error = ENOPROTOOPT;
 939                         break;
 940                 }
 941                 break;
 942         case SOPT_GET:
 943                 switch (sopt->sopt_name) {
 944 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 945 #ifdef INET
 946                 case UDP_ENCAP:
 947                         if (!IPSEC_ENABLED(ipv4)) {
 948                                 INP_WUNLOCK(inp);
 949                                 return (ENOPROTOOPT);
 950                         }
 951                         error = UDPENCAP_PCBCTL(inp, sopt);
 952                         break;
 953 #endif /* INET */
 954 #endif /* IPSEC */
 955                 case UDPLITE_SEND_CSCOV:
 956                 case UDPLITE_RECV_CSCOV:
 957                         if (!isudplite) {
 958                                 INP_WUNLOCK(inp);
 959                                 error = ENOPROTOOPT;
 960                                 break;
 961                         }
 962                         up = intoudpcb(inp);
 963                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
 964                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
 965                                 optval = up->u_txcslen;
 966                         else
 967                                 optval = up->u_rxcslen;
 968                         INP_WUNLOCK(inp);
 969                         error = sooptcopyout(sopt, &optval, sizeof(optval));
 970                         break;
 971                 default:
 972                         INP_WUNLOCK(inp);
 973                         error = ENOPROTOOPT;
 974                         break;
 975                 }
 976                 break;
 977         }
 978         return (error);
 979 }
 980
 981 #ifdef INET
 982 #ifdef INET6
 983 /* The logic here is derived from ip6_setpktopt(). See comments there. */
 984 static int
 985 udp_v4mapped_pktinfo(struct cmsghdr *cm, struct sockaddr_in * src,
 986     struct inpcb *inp, int flags)
 987 {
 988         struct ifnet *ifp;
 989         struct in6_pktinfo *pktinfo;
 990         struct in_addr ia;
 991
 992         if ((flags & PRUS_IPV6) == 0)
 993                 return (0);
 994
 995         if (cm->cmsg_level != IPPROTO_IPV6)
 996                 return (0);
 997
 998         if  (cm->cmsg_type != IPV6_2292PKTINFO &&
 999             cm->cmsg_type != IPV6_PKTINFO)
1000                 return (0);
1001
1002         if (cm->cmsg_len !=
1003             CMSG_LEN(sizeof(struct in6_pktinfo)))
1004                 return (EINVAL);
1005
1006         pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm);
1007         if (!IN6_IS_ADDR_V4MAPPED(&pktinfo->ipi6_addr) &&
1008             !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr))
1009                 return (EINVAL);
1010
1011         /* Validate the interface index if specified. */
1012         if (pktinfo->ipi6_ifindex) {
1013                 struct epoch_tracker et;
1014
1015                 NET_EPOCH_ENTER(et);
1016                 ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
1017                 NET_EPOCH_EXIT(et);     /* XXXGL: unsafe ifp */
1018                 if (ifp == NULL)
1019                         return (ENXIO);
1020         } else
1021                 ifp = NULL;
1022         if (ifp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
1023                 ia.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1024                 if (in_ifhasaddr(ifp, ia) == 0)
1025                         return (EADDRNOTAVAIL);
1026         }
1027
1028         bzero(src, sizeof(*src));
1029         src->sin_family = AF_INET;
1030         src->sin_len = sizeof(*src);
1031         src->sin_port = inp->inp_lport;
1032         src->sin_addr.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1033
1034         return (0);
1035 }
1036 #endif  /* INET6 */
1037
1038 int
1039 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1040     struct mbuf *control, struct thread *td)
1041 {
1042         struct inpcb *inp;
1043         struct udpiphdr *ui;
1044         int len, error = 0;
1045         struct in_addr faddr, laddr;
1046         struct cmsghdr *cm;
1047         struct inpcbinfo *pcbinfo;
1048         struct sockaddr_in *sin, src;
1049         struct epoch_tracker et;
1050         int cscov_partial = 0;
1051         int ipflags = 0;
1052         u_short fport, lport;
1053         u_char tos;
1054         uint8_t pr;
1055         uint16_t cscov = 0;
1056         uint32_t flowid = 0;
1057         uint8_t flowtype = M_HASHTYPE_NONE;
1058
1059         inp = sotoinpcb(so);
1060         KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1061
1062         if (addr != NULL) {
1063                 if (addr->sa_family != AF_INET)
1064                         error = EAFNOSUPPORT;
1065                 else if (addr->sa_len != sizeof(struct sockaddr_in))
1066                         error = EINVAL;
1067                 if (__predict_false(error != 0)) {
1068                         m_freem(control);
1069                         m_freem(m);
1070                         return (error);
1071                 }
1072         }
1073
1074         len = m->m_pkthdr.len;
1075         if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1076                 if (control)
1077                         m_freem(control);
1078                 m_freem(m);
1079                 return (EMSGSIZE);
1080         }
1081
1082         src.sin_family = 0;
1083         sin = (struct sockaddr_in *)addr;
1084
1085         /*
1086          * udp_send() may need to temporarily bind or connect the current
1087          * inpcb.  As such, we don't know up front whether we will need the
1088          * pcbinfo lock or not.  Do any work to decide what is needed up
1089          * front before acquiring any locks.
1090          *
1091          * We will need network epoch in either case, to safely lookup into
1092          * pcb hash.
1093          */
1094         if (sin == NULL ||
1095             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0))
1096                 INP_WLOCK(inp);
1097         else
1098                 INP_RLOCK(inp);
1099         NET_EPOCH_ENTER(et);
1100         tos = inp->inp_ip_tos;
1101         if (control != NULL) {
1102                 /*
1103                  * XXX: Currently, we assume all the optional information is
1104                  * stored in a single mbuf.
1105                  */
1106                 if (control->m_next) {
1107                         m_freem(control);
1108                         error = EINVAL;
1109                         goto release;
1110                 }
1111                 for (; control->m_len > 0;
1112                     control->m_data += CMSG_ALIGN(cm->cmsg_len),
1113                     control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1114                         cm = mtod(control, struct cmsghdr *);
1115                         if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1116                             || cm->cmsg_len > control->m_len) {
1117                                 error = EINVAL;
1118                                 break;
1119                         }
1120 #ifdef INET6
1121                         error = udp_v4mapped_pktinfo(cm, &src, inp, flags);
1122                         if (error != 0)
1123                                 break;
1124 #endif
1125                         if (cm->cmsg_level != IPPROTO_IP)
1126                                 continue;
1127
1128                         switch (cm->cmsg_type) {
1129                         case IP_SENDSRCADDR:
1130                                 if (cm->cmsg_len !=
1131                                     CMSG_LEN(sizeof(struct in_addr))) {
1132                                         error = EINVAL;
1133                                         break;
1134                                 }
1135                                 bzero(&src, sizeof(src));
1136                                 src.sin_family = AF_INET;
1137                                 src.sin_len = sizeof(src);
1138                                 src.sin_port = inp->inp_lport;
1139                                 src.sin_addr =
1140                                     *(struct in_addr *)CMSG_DATA(cm);
1141                                 break;
1142
1143                         case IP_TOS:
1144                                 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1145                                         error = EINVAL;
1146                                         break;
1147                                 }
1148                                 tos = *(u_char *)CMSG_DATA(cm);
1149                                 break;
1150
1151                         case IP_FLOWID:
1152                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1153                                         error = EINVAL;
1154                                         break;
1155                                 }
1156                                 flowid = *(uint32_t *) CMSG_DATA(cm);
1157                                 break;
1158
1159                         case IP_FLOWTYPE:
1160                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1161                                         error = EINVAL;
1162                                         break;
1163                                 }
1164                                 flowtype = *(uint32_t *) CMSG_DATA(cm);
1165                                 break;
1166
1167 #ifdef  RSS
1168                         case IP_RSSBUCKETID:
1169                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1170                                         error = EINVAL;
1171                                         break;
1172                                 }
1173                                 /* This is just a placeholder for now */
1174                                 break;
1175 #endif  /* RSS */
1176                         default:
1177                                 error = ENOPROTOOPT;
1178                                 break;
1179                         }
1180                         if (error)
1181                                 break;
1182                 }
1183                 m_freem(control);
1184                 control = NULL;
1185         }
1186         if (error)
1187                 goto release;
1188
1189         pr = inp->inp_socket->so_proto->pr_protocol;
1190         pcbinfo = udp_get_inpcbinfo(pr);
1191
1192         /*
1193          * If the IP_SENDSRCADDR control message was specified, override the
1194          * source address for this datagram.  Its use is invalidated if the
1195          * address thus specified is incomplete or clobbers other inpcbs.
1196          */
1197         laddr = inp->inp_laddr;
1198         lport = inp->inp_lport;
1199         if (src.sin_family == AF_INET) {
1200                 if ((lport == 0) ||
1201                     (laddr.s_addr == INADDR_ANY &&
1202                      src.sin_addr.s_addr == INADDR_ANY)) {
1203                         error = EINVAL;
1204                         goto release;
1205                 }
1206                 INP_HASH_WLOCK(pcbinfo);
1207                 error = in_pcbbind_setup(inp, &src, &laddr.s_addr, &lport,
1208                     td->td_ucred);
1209                 INP_HASH_WUNLOCK(pcbinfo);
1210                 if (error)
1211                         goto release;
1212         }
1213
1214         /*
1215          * If a UDP socket has been connected, then a local address/port will
1216          * have been selected and bound.
1217          *
1218          * If a UDP socket has not been connected to, then an explicit
1219          * destination address must be used, in which case a local
1220          * address/port may not have been selected and bound.
1221          */
1222         if (sin != NULL) {
1223                 INP_LOCK_ASSERT(inp);
1224                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1225                         error = EISCONN;
1226                         goto release;
1227                 }
1228
1229                 /*
1230                  * Jail may rewrite the destination address, so let it do
1231                  * that before we use it.
1232                  */
1233                 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1234                 if (error)
1235                         goto release;
1236
1237                 /*
1238                  * If a local address or port hasn't yet been selected, or if
1239                  * the destination address needs to be rewritten due to using
1240                  * a special INADDR_ constant, invoke in_pcbconnect_setup()
1241                  * to do the heavy lifting.  Once a port is selected, we
1242                  * commit the binding back to the socket; we also commit the
1243                  * binding of the address if in jail.
1244                  *
1245                  * If we already have a valid binding and we're not
1246                  * requesting a destination address rewrite, use a fast path.
1247                  */
1248                 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1249                     inp->inp_lport == 0 ||
1250                     sin->sin_addr.s_addr == INADDR_ANY ||
1251                     sin->sin_addr.s_addr == INADDR_BROADCAST) {
1252                         INP_HASH_WLOCK(pcbinfo);
1253                         error = in_pcbconnect_setup(inp, sin, &laddr.s_addr,
1254                             &lport, &faddr.s_addr, &fport, td->td_ucred);
1255                         if (error) {
1256                                 INP_HASH_WUNLOCK(pcbinfo);
1257                                 goto release;
1258                         }
1259
1260                         /*
1261                          * XXXRW: Why not commit the port if the address is
1262                          * !INADDR_ANY?
1263                          */
1264                         /* Commit the local port if newly assigned. */
1265                         if (inp->inp_laddr.s_addr == INADDR_ANY &&
1266                             inp->inp_lport == 0) {
1267                                 INP_WLOCK_ASSERT(inp);
1268                                 /*
1269                                  * Remember addr if jailed, to prevent
1270                                  * rebinding.
1271                                  */
1272                                 if (prison_flag(td->td_ucred, PR_IP4))
1273                                         inp->inp_laddr = laddr;
1274                                 inp->inp_lport = lport;
1275                                 error = in_pcbinshash(inp);
1276                                 INP_HASH_WUNLOCK(pcbinfo);
1277                                 if (error != 0) {
1278                                         inp->inp_lport = 0;
1279                                         error = EAGAIN;
1280                                         goto release;
1281                                 }
1282                                 inp->inp_flags |= INP_ANONPORT;
1283                         } else
1284                                 INP_HASH_WUNLOCK(pcbinfo);
1285                 } else {
1286                         faddr = sin->sin_addr;
1287                         fport = sin->sin_port;
1288                 }
1289         } else {
1290                 INP_LOCK_ASSERT(inp);
1291                 faddr = inp->inp_faddr;
1292                 fport = inp->inp_fport;
1293                 if (faddr.s_addr == INADDR_ANY) {
1294                         error = ENOTCONN;
1295                         goto release;
1296                 }
1297         }
1298
1299         /*
1300          * Calculate data length and get a mbuf for UDP, IP, and possible
1301          * link-layer headers.  Immediate slide the data pointer back forward
1302          * since we won't use that space at this layer.
1303          */
1304         M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1305         if (m == NULL) {
1306                 error = ENOBUFS;
1307                 goto release;
1308         }
1309         m->m_data += max_linkhdr;
1310         m->m_len -= max_linkhdr;
1311         m->m_pkthdr.len -= max_linkhdr;
1312
1313         /*
1314          * Fill in mbuf with extended UDP header and addresses and length put
1315          * into network format.
1316          */
1317         ui = mtod(m, struct udpiphdr *);
1318         bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1319         ui->ui_v = IPVERSION << 4;
1320         ui->ui_pr = pr;
1321         ui->ui_src = laddr;
1322         ui->ui_dst = faddr;
1323         ui->ui_sport = lport;
1324         ui->ui_dport = fport;
1325         ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1326         if (pr == IPPROTO_UDPLITE) {
1327                 struct udpcb *up;
1328                 uint16_t plen;
1329
1330                 up = intoudpcb(inp);
1331                 cscov = up->u_txcslen;
1332                 plen = (u_short)len + sizeof(struct udphdr);
1333                 if (cscov >= plen)
1334                         cscov = 0;
1335                 ui->ui_len = htons(plen);
1336                 ui->ui_ulen = htons(cscov);
1337                 /*
1338                  * For UDP-Lite, checksum coverage length of zero means
1339                  * the entire UDPLite packet is covered by the checksum.
1340                  */
1341                 cscov_partial = (cscov == 0) ? 0 : 1;
1342         }
1343
1344         /*
1345          * Set the Don't Fragment bit in the IP header.
1346          */
1347         if (inp->inp_flags & INP_DONTFRAG) {
1348                 struct ip *ip;
1349
1350                 ip = (struct ip *)&ui->ui_i;
1351                 ip->ip_off |= htons(IP_DF);
1352         }
1353
1354         if (inp->inp_socket->so_options & SO_DONTROUTE)
1355                 ipflags |= IP_ROUTETOIF;
1356         if (inp->inp_socket->so_options & SO_BROADCAST)
1357                 ipflags |= IP_ALLOWBROADCAST;
1358         if (inp->inp_flags & INP_ONESBCAST)
1359                 ipflags |= IP_SENDONES;
1360
1361 #ifdef MAC
1362         mac_inpcb_create_mbuf(inp, m);
1363 #endif
1364
1365         /*
1366          * Set up checksum and output datagram.
1367          */
1368         ui->ui_sum = 0;
1369         if (pr == IPPROTO_UDPLITE) {
1370                 if (inp->inp_flags & INP_ONESBCAST)
1371                         faddr.s_addr = INADDR_BROADCAST;
1372                 if (cscov_partial) {
1373                         if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1374                                 ui->ui_sum = 0xffff;
1375                 } else {
1376                         if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1377                                 ui->ui_sum = 0xffff;
1378                 }
1379         } else if (V_udp_cksum) {
1380                 if (inp->inp_flags & INP_ONESBCAST)
1381                         faddr.s_addr = INADDR_BROADCAST;
1382                 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1383                     htons((u_short)len + sizeof(struct udphdr) + pr));
1384                 m->m_pkthdr.csum_flags = CSUM_UDP;
1385                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1386         }
1387         ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1388         ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1389         ((struct ip *)ui)->ip_tos = tos;                /* XXX */
1390         UDPSTAT_INC(udps_opackets);
1391
1392         /*
1393          * Setup flowid / RSS information for outbound socket.
1394          *
1395          * Once the UDP code decides to set a flowid some other way,
1396          * this allows the flowid to be overridden by userland.
1397          */
1398         if (flowtype != M_HASHTYPE_NONE) {
1399                 m->m_pkthdr.flowid = flowid;
1400                 M_HASHTYPE_SET(m, flowtype);
1401         }
1402 #if defined(ROUTE_MPATH) || defined(RSS)
1403         else if (CALC_FLOWID_OUTBOUND_SENDTO) {
1404                 uint32_t hash_val, hash_type;
1405
1406                 hash_val = fib4_calc_packet_hash(laddr, faddr,
1407                     lport, fport, pr, &hash_type);
1408                 m->m_pkthdr.flowid = hash_val;
1409                 M_HASHTYPE_SET(m, hash_type);
1410         }
1411
1412         /*
1413          * Don't override with the inp cached flowid value.
1414          *
1415          * Depending upon the kind of send being done, the inp
1416          * flowid/flowtype values may actually not be appropriate
1417          * for this particular socket send.
1418          *
1419          * We should either leave the flowid at zero (which is what is
1420          * currently done) or set it to some software generated
1421          * hash value based on the packet contents.
1422          */
1423         ipflags |= IP_NODEFAULTFLOWID;
1424 #endif  /* RSS */
1425
1426         if (pr == IPPROTO_UDPLITE)
1427                 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1428         else
1429                 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1430         error = ip_output(m, inp->inp_options,
1431             INP_WLOCKED(inp) ? &inp->inp_route : NULL, ipflags,
1432             inp->inp_moptions, inp);
1433         INP_UNLOCK(inp);
1434         NET_EPOCH_EXIT(et);
1435         return (error);
1436
1437 release:
1438         INP_UNLOCK(inp);
1439         NET_EPOCH_EXIT(et);
1440         m_freem(m);
1441         return (error);
1442 }
1443
1444 void
1445 udp_abort(struct socket *so)
1446 {
1447         struct inpcb *inp;
1448         struct inpcbinfo *pcbinfo;
1449
1450         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1451         inp = sotoinpcb(so);
1452         KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1453         INP_WLOCK(inp);
1454         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1455                 INP_HASH_WLOCK(pcbinfo);
1456                 in_pcbdisconnect(inp);
1457                 INP_HASH_WUNLOCK(pcbinfo);
1458                 soisdisconnected(so);
1459         }
1460         INP_WUNLOCK(inp);
1461 }
1462
1463 static int
1464 udp_attach(struct socket *so, int proto, struct thread *td)
1465 {
1466         static uint32_t udp_flowid;
1467         struct inpcbinfo *pcbinfo;
1468         struct inpcb *inp;
1469         struct udpcb *up;
1470         int error;
1471
1472         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1473         inp = sotoinpcb(so);
1474         KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1475         error = soreserve(so, udp_sendspace, udp_recvspace);
1476         if (error)
1477                 return (error);
1478         error = in_pcballoc(so, pcbinfo);
1479         if (error)
1480                 return (error);
1481
1482         inp = sotoinpcb(so);
1483         inp->inp_ip_ttl = V_ip_defttl;
1484         inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1485         inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1486         up = intoudpcb(inp);
1487         bzero(&up->u_start_zero, u_zero_size);
1488         INP_WUNLOCK(inp);
1489
1490         return (0);
1491 }
1492 #endif /* INET */
1493
1494 int
1495 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1496 {
1497         struct inpcb *inp;
1498         struct udpcb *up;
1499
1500         KASSERT(so->so_type == SOCK_DGRAM,
1501             ("udp_set_kernel_tunneling: !dgram"));
1502         inp = sotoinpcb(so);
1503         KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1504         INP_WLOCK(inp);
1505         up = intoudpcb(inp);
1506         if ((f != NULL || i != NULL) && ((up->u_tun_func != NULL) ||
1507             (up->u_icmp_func != NULL))) {
1508                 INP_WUNLOCK(inp);
1509                 return (EBUSY);
1510         }
1511         up->u_tun_func = f;
1512         up->u_icmp_func = i;
1513         up->u_tun_ctx = ctx;
1514         INP_WUNLOCK(inp);
1515         return (0);
1516 }
1517
1518 #ifdef INET
1519 static int
1520 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1521 {
1522         struct inpcb *inp;
1523         struct inpcbinfo *pcbinfo;
1524         struct sockaddr_in *sinp;
1525         int error;
1526
1527         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1528         inp = sotoinpcb(so);
1529         KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1530
1531         sinp = (struct sockaddr_in *)nam;
1532         if (nam->sa_family != AF_INET) {
1533                 /*
1534                  * Preserve compatibility with old programs.
1535                  */
1536                 if (nam->sa_family != AF_UNSPEC ||
1537                     nam->sa_len < offsetof(struct sockaddr_in, sin_zero) ||
1538                     sinp->sin_addr.s_addr != INADDR_ANY)
1539                         return (EAFNOSUPPORT);
1540                 nam->sa_family = AF_INET;
1541         }
1542         if (nam->sa_len != sizeof(struct sockaddr_in))
1543                 return (EINVAL);
1544
1545         INP_WLOCK(inp);
1546         INP_HASH_WLOCK(pcbinfo);
1547         error = in_pcbbind(inp, sinp, td->td_ucred);
1548         INP_HASH_WUNLOCK(pcbinfo);
1549         INP_WUNLOCK(inp);
1550         return (error);
1551 }
1552
1553 static void
1554 udp_close(struct socket *so)
1555 {
1556         struct inpcb *inp;
1557         struct inpcbinfo *pcbinfo;
1558
1559         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1560         inp = sotoinpcb(so);
1561         KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1562         INP_WLOCK(inp);
1563         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1564                 INP_HASH_WLOCK(pcbinfo);
1565                 in_pcbdisconnect(inp);
1566                 INP_HASH_WUNLOCK(pcbinfo);
1567                 soisdisconnected(so);
1568         }
1569         INP_WUNLOCK(inp);
1570 }
1571
1572 static int
1573 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1574 {
1575         struct epoch_tracker et;
1576         struct inpcb *inp;
1577         struct inpcbinfo *pcbinfo;
1578         struct sockaddr_in *sin;
1579         int error;
1580
1581         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1582         inp = sotoinpcb(so);
1583         KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1584
1585         sin = (struct sockaddr_in *)nam;
1586         if (sin->sin_family != AF_INET)
1587                 return (EAFNOSUPPORT);
1588         if (sin->sin_len != sizeof(*sin))
1589                 return (EINVAL);
1590
1591         INP_WLOCK(inp);
1592         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1593                 INP_WUNLOCK(inp);
1594                 return (EISCONN);
1595         }
1596         error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1597         if (error != 0) {
1598                 INP_WUNLOCK(inp);
1599                 return (error);
1600         }
1601         NET_EPOCH_ENTER(et);
1602         INP_HASH_WLOCK(pcbinfo);
1603         error = in_pcbconnect(inp, sin, td->td_ucred, true);
1604         INP_HASH_WUNLOCK(pcbinfo);
1605         NET_EPOCH_EXIT(et);
1606         if (error == 0)
1607                 soisconnected(so);
1608         INP_WUNLOCK(inp);
1609         return (error);
1610 }
1611
1612 static void
1613 udp_detach(struct socket *so)
1614 {
1615         struct inpcb *inp;
1616
1617         inp = sotoinpcb(so);
1618         KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1619         KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1620             ("udp_detach: not disconnected"));
1621         INP_WLOCK(inp);
1622         in_pcbdetach(inp);
1623         in_pcbfree(inp);
1624 }
1625
1626 int
1627 udp_disconnect(struct socket *so)
1628 {
1629         struct inpcb *inp;
1630         struct inpcbinfo *pcbinfo;
1631
1632         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1633         inp = sotoinpcb(so);
1634         KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1635         INP_WLOCK(inp);
1636         if (inp->inp_faddr.s_addr == INADDR_ANY) {
1637                 INP_WUNLOCK(inp);
1638                 return (ENOTCONN);
1639         }
1640         INP_HASH_WLOCK(pcbinfo);
1641         in_pcbdisconnect(inp);
1642         INP_HASH_WUNLOCK(pcbinfo);
1643         SOCK_LOCK(so);
1644         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1645         SOCK_UNLOCK(so);
1646         INP_WUNLOCK(inp);
1647         return (0);
1648 }
1649 #endif /* INET */
1650
1651 int
1652 udp_shutdown(struct socket *so)
1653 {
1654         struct inpcb *inp;
1655
1656         inp = sotoinpcb(so);
1657         KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1658         INP_WLOCK(inp);
1659         socantsendmore(so);
1660         INP_WUNLOCK(inp);
1661         return (0);
1662 }
1663
1664 #ifdef INET
1665 #define UDP_PROTOSW                                                     \
1666         .pr_type =              SOCK_DGRAM,                             \
1667         .pr_flags =             PR_ATOMIC | PR_ADDR | PR_CAPATTACH,     \
1668         .pr_ctloutput =         udp_ctloutput,                          \
1669         .pr_abort =             udp_abort,                              \
1670         .pr_attach =            udp_attach,                             \
1671         .pr_bind =              udp_bind,                               \
1672         .pr_connect =           udp_connect,                            \
1673         .pr_control =           in_control,                             \
1674         .pr_detach =            udp_detach,                             \
1675         .pr_disconnect =        udp_disconnect,                         \
1676         .pr_peeraddr =          in_getpeeraddr,                         \
1677         .pr_send =              udp_send,                               \
1678         .pr_soreceive =         soreceive_dgram,                        \
1679         .pr_sosend =            sosend_dgram,                           \
1680         .pr_shutdown =          udp_shutdown,                           \
1681         .pr_sockaddr =          in_getsockaddr,                         \
1682         .pr_sosetlabel =        in_pcbsosetlabel,                       \
1683         .pr_close =             udp_close
1684
1685 struct protosw udp_protosw = {
1686         .pr_protocol =          IPPROTO_UDP,
1687         UDP_PROTOSW
1688 };
1689
1690 struct protosw udplite_protosw = {
1691         .pr_protocol =          IPPROTO_UDPLITE,
1692         UDP_PROTOSW
1693 };
1694
1695 static void
1696 udp_init(void *arg __unused)
1697 {
1698
1699         IPPROTO_REGISTER(IPPROTO_UDP, udp_input, udp_ctlinput);
1700         IPPROTO_REGISTER(IPPROTO_UDPLITE, udp_input, udplite_ctlinput);
1701 }
1702 SYSINIT(udp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, udp_init, NULL);
1703 #endif /* INET */