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_route.h"
  48 #include "opt_rss.h"
  49
  50 #include <sys/param.h>
  51 #include <sys/domain.h>
  52 #include <sys/eventhandler.h>
  53 #include <sys/jail.h>
  54 #include <sys/kernel.h>
  55 #include <sys/lock.h>
  56 #include <sys/malloc.h>
  57 #include <sys/mbuf.h>
  58 #include <sys/priv.h>
  59 #include <sys/proc.h>
  60 #include <sys/protosw.h>
  61 #include <sys/sdt.h>
  62 #include <sys/signalvar.h>
  63 #include <sys/socket.h>
  64 #include <sys/socketvar.h>
  65 #include <sys/sx.h>
  66 #include <sys/sysctl.h>
  67 #include <sys/syslog.h>
  68 #include <sys/systm.h>
  69
  70 #include <vm/uma.h>
  71
  72 #include <net/if.h>
  73 #include <net/if_var.h>
  74 #include <net/route.h>
  75 #include <net/route/nhop.h>
  76 #include <net/rss_config.h>
  77
  78 #include <netinet/in.h>
  79 #include <netinet/in_kdtrace.h>
  80 #include <netinet/in_fib.h>
  81 #include <netinet/in_pcb.h>
  82 #include <netinet/in_systm.h>
  83 #include <netinet/in_var.h>
  84 #include <netinet/ip.h>
  85 #ifdef INET6
  86 #include <netinet/ip6.h>
  87 #endif
  88 #include <netinet/ip_icmp.h>
  89 #include <netinet/icmp_var.h>
  90 #include <netinet/ip_var.h>
  91 #include <netinet/ip_options.h>
  92 #ifdef INET6
  93 #include <netinet6/ip6_var.h>
  94 #endif
  95 #include <netinet/udp.h>
  96 #include <netinet/udp_var.h>
  97 #include <netinet/udplite.h>
  98 #include <netinet/in_rss.h>
  99
 100 #include <netipsec/ipsec_support.h>
 101
 102 #include <machine/in_cksum.h>
 103
 104 #include <security/mac/mac_framework.h>
 105
 106 /*
 107  * UDP and UDP-Lite protocols implementation.
 108  * Per RFC 768, August, 1980.
 109  * Per RFC 3828, July, 2004.
 110  */
 111
 112 /*
 113  * BSD 4.2 defaulted the udp checksum to be off.  Turning off udp checksums
 114  * removes the only data integrity mechanism for packets and malformed
 115  * packets that would otherwise be discarded due to bad checksums, and may
 116  * cause problems (especially for NFS data blocks).
 117  */
 118 VNET_DEFINE(int, udp_cksum) = 1;
 119 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW,
 120     &VNET_NAME(udp_cksum), 0, "compute udp checksum");
 121
 122 VNET_DEFINE(int, udp_log_in_vain) = 0;
 123 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW,
 124     &VNET_NAME(udp_log_in_vain), 0, "Log all incoming UDP packets");
 125
 126 VNET_DEFINE(int, udp_blackhole) = 0;
 127 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW,
 128     &VNET_NAME(udp_blackhole), 0,
 129     "Do not send port unreachables for refused connects");
 130 VNET_DEFINE(bool, udp_blackhole_local) = false;
 131 SYSCTL_BOOL(_net_inet_udp, OID_AUTO, blackhole_local, CTLFLAG_VNET |
 132     CTLFLAG_RW, &VNET_NAME(udp_blackhole_local), false,
 133     "Enforce net.inet.udp.blackhole for locally originated packets");
 134
 135 u_long  udp_sendspace = 9216;           /* really max datagram size */
 136 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW,
 137     &udp_sendspace, 0, "Maximum outgoing UDP datagram size");
 138
 139 u_long  udp_recvspace = 40 * (1024 +
 140 #ifdef INET6
 141                                       sizeof(struct sockaddr_in6)
 142 #else
 143                                       sizeof(struct sockaddr_in)
 144 #endif
 145                                       );        /* 40 1K datagrams */
 146
 147 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW,
 148     &udp_recvspace, 0, "Maximum space for incoming UDP datagrams");
 149
 150 VNET_DEFINE(struct inpcbinfo, udbinfo);
 151 VNET_DEFINE(struct inpcbinfo, ulitecbinfo);
 152
 153 #ifndef UDBHASHSIZE
 154 #define UDBHASHSIZE     128
 155 #endif
 156
 157 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat);          /* from udp_var.h */
 158 VNET_PCPUSTAT_SYSINIT(udpstat);
 159 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat,
 160     udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)");
 161
 162 #ifdef VIMAGE
 163 VNET_PCPUSTAT_SYSUNINIT(udpstat);
 164 #endif /* VIMAGE */
 165 #ifdef INET
 166 static void     udp_detach(struct socket *so);
 167 #endif
 168
 169 INPCBSTORAGE_DEFINE(udpcbstor, udpcb, "udpinp", "udp_inpcb", "udp", "udphash");
 170 INPCBSTORAGE_DEFINE(udplitecbstor, udpcb, "udpliteinp", "udplite_inpcb",
 171     "udplite", "udplitehash");
 172
 173 static void
 174 udp_vnet_init(void *arg __unused)
 175 {
 176
 177         /*
 178          * For now default to 2-tuple UDP hashing - until the fragment
 179          * reassembly code can also update the flowid.
 180          *
 181          * Once we can calculate the flowid that way and re-establish
 182          * a 4-tuple, flip this to 4-tuple.
 183          */
 184         in_pcbinfo_init(&V_udbinfo, &udpcbstor, UDBHASHSIZE, UDBHASHSIZE);
 185         /* Additional pcbinfo for UDP-Lite */
 186         in_pcbinfo_init(&V_ulitecbinfo, &udplitecbstor, UDBHASHSIZE,
 187             UDBHASHSIZE);
 188 }
 189 VNET_SYSINIT(udp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
 190     udp_vnet_init, NULL);
 191
 192 /*
 193  * Kernel module interface for updating udpstat.  The argument is an index
 194  * into udpstat treated as an array of u_long.  While this encodes the
 195  * general layout of udpstat into the caller, it doesn't encode its location,
 196  * so that future changes to add, for example, per-CPU stats support won't
 197  * cause binary compatibility problems for kernel modules.
 198  */
 199 void
 200 kmod_udpstat_inc(int statnum)
 201 {
 202
 203         counter_u64_add(VNET(udpstat)[statnum], 1);
 204 }
 205
 206 #ifdef VIMAGE
 207 static void
 208 udp_destroy(void *unused __unused)
 209 {
 210
 211         in_pcbinfo_destroy(&V_udbinfo);
 212         in_pcbinfo_destroy(&V_ulitecbinfo);
 213 }
 214 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL);
 215 #endif
 216
 217 #ifdef INET
 218 /*
 219  * Subroutine of udp_input(), which appends the provided mbuf chain to the
 220  * passed pcb/socket.  The caller must provide a sockaddr_in via udp_in that
 221  * contains the source address.  If the socket ends up being an IPv6 socket,
 222  * udp_append() will convert to a sockaddr_in6 before passing the address
 223  * into the socket code.
 224  *
 225  * In the normal case udp_append() will return 0, indicating that you
 226  * must unlock the inp. However if a tunneling protocol is in place we increment
 227  * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we
 228  * then decrement the reference count. If the inp_rele returns 1, indicating the
 229  * inp is gone, we return that to the caller to tell them *not* to unlock
 230  * the inp. In the case of multi-cast this will cause the distribution
 231  * to stop (though most tunneling protocols known currently do *not* use
 232  * multicast).
 233  */
 234 static int
 235 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off,
 236     struct sockaddr_in *udp_in)
 237 {
 238         struct sockaddr *append_sa;
 239         struct socket *so;
 240         struct mbuf *tmpopts, *opts = NULL;
 241 #ifdef INET6
 242         struct sockaddr_in6 udp_in6;
 243 #endif
 244         struct udpcb *up;
 245         bool filtered;
 246
 247         INP_LOCK_ASSERT(inp);
 248
 249         /*
 250          * Engage the tunneling protocol.
 251          */
 252         up = intoudpcb(inp);
 253         if (up->u_tun_func != NULL) {
 254                 in_pcbref(inp);
 255                 INP_RUNLOCK(inp);
 256                 filtered = (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0],
 257                     up->u_tun_ctx);
 258                 INP_RLOCK(inp);
 259                 if (filtered)
 260                         return (in_pcbrele_rlocked(inp));
 261         }
 262
 263         off += sizeof(struct udphdr);
 264
 265 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 266         /* Check AH/ESP integrity. */
 267         if (IPSEC_ENABLED(ipv4) &&
 268             IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) {
 269                 m_freem(n);
 270                 return (0);
 271         }
 272         if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */
 273                 if (IPSEC_ENABLED(ipv4) &&
 274                     UDPENCAP_INPUT(n, off, AF_INET) != 0)
 275                         return (0);     /* Consumed. */
 276         }
 277 #endif /* IPSEC */
 278 #ifdef MAC
 279         if (mac_inpcb_check_deliver(inp, n) != 0) {
 280                 m_freem(n);
 281                 return (0);
 282         }
 283 #endif /* MAC */
 284         if (inp->inp_flags & INP_CONTROLOPTS ||
 285             inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) {
 286 #ifdef INET6
 287                 if (inp->inp_vflag & INP_IPV6)
 288                         (void)ip6_savecontrol_v4(inp, n, &opts, NULL);
 289                 else
 290 #endif /* INET6 */
 291                         ip_savecontrol(inp, &opts, ip, n);
 292         }
 293         if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) {
 294                 tmpopts = sbcreatecontrol(&udp_in[1],
 295                     sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP,
 296                     M_NOWAIT);
 297                 if (tmpopts) {
 298                         if (opts) {
 299                                 tmpopts->m_next = opts;
 300                                 opts = tmpopts;
 301                         } else
 302                                 opts = tmpopts;
 303                 }
 304         }
 305 #ifdef INET6
 306         if (inp->inp_vflag & INP_IPV6) {
 307                 bzero(&udp_in6, sizeof(udp_in6));
 308                 udp_in6.sin6_len = sizeof(udp_in6);
 309                 udp_in6.sin6_family = AF_INET6;
 310                 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6);
 311                 append_sa = (struct sockaddr *)&udp_in6;
 312         } else
 313 #endif /* INET6 */
 314                 append_sa = (struct sockaddr *)&udp_in[0];
 315         m_adj(n, off);
 316
 317         so = inp->inp_socket;
 318         SOCKBUF_LOCK(&so->so_rcv);
 319         if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) {
 320                 soroverflow_locked(so);
 321                 m_freem(n);
 322                 if (opts)
 323                         m_freem(opts);
 324                 UDPSTAT_INC(udps_fullsock);
 325         } else
 326                 sorwakeup_locked(so);
 327         return (0);
 328 }
 329
 330 static bool
 331 udp_multi_match(const struct inpcb *inp, void *v)
 332 {
 333         struct ip *ip = v;
 334         struct udphdr *uh = (struct udphdr *)(ip + 1);
 335
 336         if (inp->inp_lport != uh->uh_dport)
 337                 return (false);
 338 #ifdef INET6
 339         if ((inp->inp_vflag & INP_IPV4) == 0)
 340                 return (false);
 341 #endif
 342         if (inp->inp_laddr.s_addr != INADDR_ANY &&
 343             inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
 344                 return (false);
 345         if (inp->inp_faddr.s_addr != INADDR_ANY &&
 346             inp->inp_faddr.s_addr != ip->ip_src.s_addr)
 347                 return (false);
 348         if (inp->inp_fport != 0 &&
 349             inp->inp_fport != uh->uh_sport)
 350                 return (false);
 351
 352         return (true);
 353 }
 354
 355 static int
 356 udp_multi_input(struct mbuf *m, int proto, struct sockaddr_in *udp_in)
 357 {
 358         struct ip *ip = mtod(m, struct ip *);
 359         struct inpcb_iterator inpi = INP_ITERATOR(udp_get_inpcbinfo(proto),
 360             INPLOOKUP_RLOCKPCB, udp_multi_match, ip);
 361 #ifdef KDTRACE_HOOKS
 362         struct udphdr *uh = (struct udphdr *)(ip + 1);
 363 #endif
 364         struct inpcb *inp;
 365         struct mbuf *n;
 366         int appends = 0;
 367
 368         MPASS(ip->ip_hl == sizeof(struct ip) >> 2);
 369
 370         while ((inp = inp_next(&inpi)) != NULL) {
 371                 /*
 372                  * XXXRW: Because we weren't holding either the inpcb
 373                  * or the hash lock when we checked for a match
 374                  * before, we should probably recheck now that the
 375                  * inpcb lock is held.
 376                  */
 377                 /*
 378                  * Handle socket delivery policy for any-source
 379                  * and source-specific multicast. [RFC3678]
 380                  */
 381                 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
 382                         struct ip_moptions      *imo;
 383                         struct sockaddr_in       group;
 384                         int                      blocked;
 385
 386                         imo = inp->inp_moptions;
 387                         if (imo == NULL)
 388                                 continue;
 389                         bzero(&group, sizeof(struct sockaddr_in));
 390                         group.sin_len = sizeof(struct sockaddr_in);
 391                         group.sin_family = AF_INET;
 392                         group.sin_addr = ip->ip_dst;
 393
 394                         blocked = imo_multi_filter(imo, m->m_pkthdr.rcvif,
 395                                 (struct sockaddr *)&group,
 396                                 (struct sockaddr *)&udp_in[0]);
 397                         if (blocked != MCAST_PASS) {
 398                                 if (blocked == MCAST_NOTGMEMBER)
 399                                         IPSTAT_INC(ips_notmember);
 400                                 if (blocked == MCAST_NOTSMEMBER ||
 401                                     blocked == MCAST_MUTED)
 402                                         UDPSTAT_INC(udps_filtermcast);
 403                                 continue;
 404                         }
 405                 }
 406                 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
 407                         if (proto == IPPROTO_UDPLITE)
 408                                 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 409                         else
 410                                 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 411                         if (udp_append(inp, ip, n, sizeof(struct ip), udp_in)) {
 412                                 break;
 413                         } else
 414                                 appends++;
 415                 }
 416                 /*
 417                  * Don't look for additional matches if this one does
 418                  * not have either the SO_REUSEPORT or SO_REUSEADDR
 419                  * socket options set.  This heuristic avoids
 420                  * searching through all pcbs in the common case of a
 421                  * non-shared port.  It assumes that an application
 422                  * will never clear these options after setting them.
 423                  */
 424                 if ((inp->inp_socket->so_options &
 425                     (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) {
 426                         INP_RUNLOCK(inp);
 427                         break;
 428                 }
 429         }
 430
 431         if (appends == 0) {
 432                 /*
 433                  * No matching pcb found; discard datagram.  (No need
 434                  * to send an ICMP Port Unreachable for a broadcast
 435                  * or multicast datgram.)
 436                  */
 437                 UDPSTAT_INC(udps_noport);
 438                 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)))
 439                         UDPSTAT_INC(udps_noportmcast);
 440                 else
 441                         UDPSTAT_INC(udps_noportbcast);
 442         }
 443         m_freem(m);
 444
 445         return (IPPROTO_DONE);
 446 }
 447
 448 static int
 449 udp_input(struct mbuf **mp, int *offp, int proto)
 450 {
 451         struct ip *ip;
 452         struct udphdr *uh;
 453         struct ifnet *ifp;
 454         struct inpcb *inp;
 455         uint16_t len, ip_len;
 456         struct inpcbinfo *pcbinfo;
 457         struct sockaddr_in udp_in[2];
 458         struct mbuf *m;
 459         struct m_tag *fwd_tag;
 460         int cscov_partial, iphlen;
 461
 462         m = *mp;
 463         iphlen = *offp;
 464         ifp = m->m_pkthdr.rcvif;
 465         *mp = NULL;
 466         UDPSTAT_INC(udps_ipackets);
 467
 468         /*
 469          * Strip IP options, if any; should skip this, make available to
 470          * user, and use on returned packets, but we don't yet have a way to
 471          * check the checksum with options still present.
 472          */
 473         if (iphlen > sizeof (struct ip)) {
 474                 ip_stripoptions(m);
 475                 iphlen = sizeof(struct ip);
 476         }
 477
 478         /*
 479          * Get IP and UDP header together in first mbuf.
 480          */
 481         if (m->m_len < iphlen + sizeof(struct udphdr)) {
 482                 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) {
 483                         UDPSTAT_INC(udps_hdrops);
 484                         return (IPPROTO_DONE);
 485                 }
 486         }
 487         ip = mtod(m, struct ip *);
 488         uh = (struct udphdr *)((caddr_t)ip + iphlen);
 489         cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0;
 490
 491         /*
 492          * Destination port of 0 is illegal, based on RFC768.
 493          */
 494         if (uh->uh_dport == 0)
 495                 goto badunlocked;
 496
 497         /*
 498          * Construct sockaddr format source address.  Stuff source address
 499          * and datagram in user buffer.
 500          */
 501         bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2);
 502         udp_in[0].sin_len = sizeof(struct sockaddr_in);
 503         udp_in[0].sin_family = AF_INET;
 504         udp_in[0].sin_port = uh->uh_sport;
 505         udp_in[0].sin_addr = ip->ip_src;
 506         udp_in[1].sin_len = sizeof(struct sockaddr_in);
 507         udp_in[1].sin_family = AF_INET;
 508         udp_in[1].sin_port = uh->uh_dport;
 509         udp_in[1].sin_addr = ip->ip_dst;
 510
 511         /*
 512          * Make mbuf data length reflect UDP length.  If not enough data to
 513          * reflect UDP length, drop.
 514          */
 515         len = ntohs((u_short)uh->uh_ulen);
 516         ip_len = ntohs(ip->ip_len) - iphlen;
 517         if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) {
 518                 /* Zero means checksum over the complete packet. */
 519                 if (len == 0)
 520                         len = ip_len;
 521                 cscov_partial = 0;
 522         }
 523         if (ip_len != len) {
 524                 if (len > ip_len || len < sizeof(struct udphdr)) {
 525                         UDPSTAT_INC(udps_badlen);
 526                         goto badunlocked;
 527                 }
 528                 if (proto == IPPROTO_UDP)
 529                         m_adj(m, len - ip_len);
 530         }
 531
 532         /*
 533          * Checksum extended UDP header and data.
 534          */
 535         if (uh->uh_sum) {
 536                 u_short uh_sum;
 537
 538                 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
 539                     !cscov_partial) {
 540                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR)
 541                                 uh_sum = m->m_pkthdr.csum_data;
 542                         else
 543                                 uh_sum = in_pseudo(ip->ip_src.s_addr,
 544                                     ip->ip_dst.s_addr, htonl((u_short)len +
 545                                     m->m_pkthdr.csum_data + proto));
 546                         uh_sum ^= 0xffff;
 547                 } else {
 548                         char b[offsetof(struct ipovly, ih_src)];
 549                         struct ipovly *ipov = (struct ipovly *)ip;
 550
 551                         bcopy(ipov, b, sizeof(b));
 552                         bzero(ipov, sizeof(ipov->ih_x1));
 553                         ipov->ih_len = (proto == IPPROTO_UDP) ?
 554                             uh->uh_ulen : htons(ip_len);
 555                         uh_sum = in_cksum(m, len + sizeof (struct ip));
 556                         bcopy(b, ipov, sizeof(b));
 557                 }
 558                 if (uh_sum) {
 559                         UDPSTAT_INC(udps_badsum);
 560                         m_freem(m);
 561                         return (IPPROTO_DONE);
 562                 }
 563         } else {
 564                 if (proto == IPPROTO_UDP) {
 565                         UDPSTAT_INC(udps_nosum);
 566                 } else {
 567                         /* UDPLite requires a checksum */
 568                         /* XXX: What is the right UDPLite MIB counter here? */
 569                         m_freem(m);
 570                         return (IPPROTO_DONE);
 571                 }
 572         }
 573
 574         if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
 575             in_broadcast(ip->ip_dst, ifp))
 576                 return (udp_multi_input(m, proto, udp_in));
 577
 578         pcbinfo = udp_get_inpcbinfo(proto);
 579
 580         /*
 581          * Locate pcb for datagram.
 582          *
 583          * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain.
 584          */
 585         if ((m->m_flags & M_IP_NEXTHOP) &&
 586             (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) {
 587                 struct sockaddr_in *next_hop;
 588
 589                 next_hop = (struct sockaddr_in *)(fwd_tag + 1);
 590
 591                 /*
 592                  * Transparently forwarded. Pretend to be the destination.
 593                  * Already got one like this?
 594                  */
 595                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 596                     ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m);
 597                 if (!inp) {
 598                         /*
 599                          * It's new.  Try to find the ambushing socket.
 600                          * Because we've rewritten the destination address,
 601                          * any hardware-generated hash is ignored.
 602                          */
 603                         inp = in_pcblookup(pcbinfo, ip->ip_src,
 604                             uh->uh_sport, next_hop->sin_addr,
 605                             next_hop->sin_port ? htons(next_hop->sin_port) :
 606                             uh->uh_dport, INPLOOKUP_WILDCARD |
 607                             INPLOOKUP_RLOCKPCB, ifp);
 608                 }
 609                 /* Remove the tag from the packet. We don't need it anymore. */
 610                 m_tag_delete(m, fwd_tag);
 611                 m->m_flags &= ~M_IP_NEXTHOP;
 612         } else
 613                 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport,
 614                     ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD |
 615                     INPLOOKUP_RLOCKPCB, ifp, m);
 616         if (inp == NULL) {
 617                 if (V_udp_log_in_vain) {
 618                         char src[INET_ADDRSTRLEN];
 619                         char dst[INET_ADDRSTRLEN];
 620
 621                         log(LOG_INFO,
 622                             "Connection attempt to UDP %s:%d from %s:%d\n",
 623                             inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport),
 624                             inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport));
 625                 }
 626                 if (proto == IPPROTO_UDPLITE)
 627                         UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh);
 628                 else
 629                         UDP_PROBE(receive, NULL, NULL, ip, NULL, uh);
 630                 UDPSTAT_INC(udps_noport);
 631                 if (m->m_flags & (M_BCAST | M_MCAST)) {
 632                         UDPSTAT_INC(udps_noportbcast);
 633                         goto badunlocked;
 634                 }
 635                 if (V_udp_blackhole && (V_udp_blackhole_local ||
 636                     !in_localip(ip->ip_src)))
 637                         goto badunlocked;
 638                 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0)
 639                         goto badunlocked;
 640                 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
 641                 return (IPPROTO_DONE);
 642         }
 643
 644         /*
 645          * Check the minimum TTL for socket.
 646          */
 647         INP_RLOCK_ASSERT(inp);
 648         if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) {
 649                 if (proto == IPPROTO_UDPLITE)
 650                         UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 651                 else
 652                         UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 653                 INP_RUNLOCK(inp);
 654                 m_freem(m);
 655                 return (IPPROTO_DONE);
 656         }
 657         if (cscov_partial) {
 658                 struct udpcb *up;
 659
 660                 up = intoudpcb(inp);
 661                 if (up->u_rxcslen == 0 || up->u_rxcslen > len) {
 662                         INP_RUNLOCK(inp);
 663                         m_freem(m);
 664                         return (IPPROTO_DONE);
 665                 }
 666         }
 667
 668         if (proto == IPPROTO_UDPLITE)
 669                 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh);
 670         else
 671                 UDP_PROBE(receive, NULL, inp, ip, inp, uh);
 672         if (udp_append(inp, ip, m, iphlen, udp_in) == 0)
 673                 INP_RUNLOCK(inp);
 674         return (IPPROTO_DONE);
 675
 676 badunlocked:
 677         m_freem(m);
 678         return (IPPROTO_DONE);
 679 }
 680 #endif /* INET */
 681
 682 /*
 683  * Notify a udp user of an asynchronous error; just wake up so that they can
 684  * collect error status.
 685  */
 686 struct inpcb *
 687 udp_notify(struct inpcb *inp, int errno)
 688 {
 689
 690         INP_WLOCK_ASSERT(inp);
 691         if ((errno == EHOSTUNREACH || errno == ENETUNREACH ||
 692              errno == EHOSTDOWN) && inp->inp_route.ro_nh) {
 693                 NH_FREE(inp->inp_route.ro_nh);
 694                 inp->inp_route.ro_nh = (struct nhop_object *)NULL;
 695         }
 696
 697         inp->inp_socket->so_error = errno;
 698         sorwakeup(inp->inp_socket);
 699         sowwakeup(inp->inp_socket);
 700         return (inp);
 701 }
 702
 703 #ifdef INET
 704 static void
 705 udp_common_ctlinput(struct icmp *icmp, struct inpcbinfo *pcbinfo)
 706 {
 707         struct ip *ip = &icmp->icmp_ip;
 708         struct udphdr *uh;
 709         struct inpcb *inp;
 710
 711         if (icmp_errmap(icmp) == 0)
 712                 return;
 713
 714         uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
 715         inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport, ip->ip_src,
 716             uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL);
 717         if (inp != NULL) {
 718                 INP_WLOCK_ASSERT(inp);
 719                 if (inp->inp_socket != NULL)
 720                         udp_notify(inp, icmp_errmap(icmp));
 721                 INP_WUNLOCK(inp);
 722         } else {
 723                 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport,
 724                     ip->ip_src, uh->uh_sport,
 725                     INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 726                 if (inp != NULL) {
 727                         struct udpcb *up;
 728                         udp_tun_icmp_t *func;
 729
 730                         up = intoudpcb(inp);
 731                         func = up->u_icmp_func;
 732                         INP_RUNLOCK(inp);
 733                         if (func != NULL)
 734                                 func(icmp);
 735                 }
 736         }
 737 }
 738
 739 static void
 740 udp_ctlinput(struct icmp *icmp)
 741 {
 742
 743         return (udp_common_ctlinput(icmp, &V_udbinfo));
 744 }
 745
 746 static void
 747 udplite_ctlinput(struct icmp *icmp)
 748 {
 749
 750         return (udp_common_ctlinput(icmp, &V_ulitecbinfo));
 751 }
 752 #endif /* INET */
 753
 754 static int
 755 udp_pcblist(SYSCTL_HANDLER_ARGS)
 756 {
 757         struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_udbinfo,
 758             INPLOOKUP_RLOCKPCB);
 759         struct xinpgen xig;
 760         struct inpcb *inp;
 761         int error;
 762
 763         if (req->newptr != 0)
 764                 return (EPERM);
 765
 766         if (req->oldptr == 0) {
 767                 int n;
 768
 769                 n = V_udbinfo.ipi_count;
 770                 n += imax(n / 8, 10);
 771                 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
 772                 return (0);
 773         }
 774
 775         if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
 776                 return (error);
 777
 778         bzero(&xig, sizeof(xig));
 779         xig.xig_len = sizeof xig;
 780         xig.xig_count = V_udbinfo.ipi_count;
 781         xig.xig_gen = V_udbinfo.ipi_gencnt;
 782         xig.xig_sogen = so_gencnt;
 783         error = SYSCTL_OUT(req, &xig, sizeof xig);
 784         if (error)
 785                 return (error);
 786
 787         while ((inp = inp_next(&inpi)) != NULL) {
 788                 if (inp->inp_gencnt <= xig.xig_gen &&
 789                     cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
 790                         struct xinpcb xi;
 791
 792                         in_pcbtoxinpcb(inp, &xi);
 793                         error = SYSCTL_OUT(req, &xi, sizeof xi);
 794                         if (error) {
 795                                 INP_RUNLOCK(inp);
 796                                 break;
 797                         }
 798                 }
 799         }
 800
 801         if (!error) {
 802                 /*
 803                  * Give the user an updated idea of our state.  If the
 804                  * generation differs from what we told her before, she knows
 805                  * that something happened while we were processing this
 806                  * request, and it might be necessary to retry.
 807                  */
 808                 xig.xig_gen = V_udbinfo.ipi_gencnt;
 809                 xig.xig_sogen = so_gencnt;
 810                 xig.xig_count = V_udbinfo.ipi_count;
 811                 error = SYSCTL_OUT(req, &xig, sizeof xig);
 812         }
 813
 814         return (error);
 815 }
 816
 817 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist,
 818     CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
 819     udp_pcblist, "S,xinpcb",
 820     "List of active UDP sockets");
 821
 822 #ifdef INET
 823 static int
 824 udp_getcred(SYSCTL_HANDLER_ARGS)
 825 {
 826         struct xucred xuc;
 827         struct sockaddr_in addrs[2];
 828         struct epoch_tracker et;
 829         struct inpcb *inp;
 830         int error;
 831
 832         error = priv_check(req->td, PRIV_NETINET_GETCRED);
 833         if (error)
 834                 return (error);
 835         error = SYSCTL_IN(req, addrs, sizeof(addrs));
 836         if (error)
 837                 return (error);
 838         NET_EPOCH_ENTER(et);
 839         inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port,
 840             addrs[0].sin_addr, addrs[0].sin_port,
 841             INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL);
 842         NET_EPOCH_EXIT(et);
 843         if (inp != NULL) {
 844                 INP_RLOCK_ASSERT(inp);
 845                 if (inp->inp_socket == NULL)
 846                         error = ENOENT;
 847                 if (error == 0)
 848                         error = cr_canseeinpcb(req->td->td_ucred, inp);
 849                 if (error == 0)
 850                         cru2x(inp->inp_cred, &xuc);
 851                 INP_RUNLOCK(inp);
 852         } else
 853                 error = ENOENT;
 854         if (error == 0)
 855                 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
 856         return (error);
 857 }
 858
 859 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred,
 860     CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE,
 861     0, 0, udp_getcred, "S,xucred",
 862     "Get the xucred of a UDP connection");
 863 #endif /* INET */
 864
 865 int
 866 udp_ctloutput(struct socket *so, struct sockopt *sopt)
 867 {
 868         struct inpcb *inp;
 869         struct udpcb *up;
 870         int isudplite, error, optval;
 871
 872         error = 0;
 873         isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0;
 874         inp = sotoinpcb(so);
 875         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 876         INP_WLOCK(inp);
 877         if (sopt->sopt_level != so->so_proto->pr_protocol) {
 878 #ifdef INET6
 879                 if (INP_CHECK_SOCKAF(so, AF_INET6)) {
 880                         INP_WUNLOCK(inp);
 881                         error = ip6_ctloutput(so, sopt);
 882                 }
 883 #endif
 884 #if defined(INET) && defined(INET6)
 885                 else
 886 #endif
 887 #ifdef INET
 888                 {
 889                         INP_WUNLOCK(inp);
 890                         error = ip_ctloutput(so, sopt);
 891                 }
 892 #endif
 893                 return (error);
 894         }
 895
 896         switch (sopt->sopt_dir) {
 897         case SOPT_SET:
 898                 switch (sopt->sopt_name) {
 899 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 900 #ifdef INET
 901                 case UDP_ENCAP:
 902                         if (!IPSEC_ENABLED(ipv4)) {
 903                                 INP_WUNLOCK(inp);
 904                                 return (ENOPROTOOPT);
 905                         }
 906                         error = UDPENCAP_PCBCTL(inp, sopt);
 907                         break;
 908 #endif /* INET */
 909 #endif /* IPSEC */
 910                 case UDPLITE_SEND_CSCOV:
 911                 case UDPLITE_RECV_CSCOV:
 912                         if (!isudplite) {
 913                                 INP_WUNLOCK(inp);
 914                                 error = ENOPROTOOPT;
 915                                 break;
 916                         }
 917                         INP_WUNLOCK(inp);
 918                         error = sooptcopyin(sopt, &optval, sizeof(optval),
 919                             sizeof(optval));
 920                         if (error != 0)
 921                                 break;
 922                         inp = sotoinpcb(so);
 923                         KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
 924                         INP_WLOCK(inp);
 925                         up = intoudpcb(inp);
 926                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
 927                         if ((optval != 0 && optval < 8) || (optval > 65535)) {
 928                                 INP_WUNLOCK(inp);
 929                                 error = EINVAL;
 930                                 break;
 931                         }
 932                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
 933                                 up->u_txcslen = optval;
 934                         else
 935                                 up->u_rxcslen = optval;
 936                         INP_WUNLOCK(inp);
 937                         break;
 938                 default:
 939                         INP_WUNLOCK(inp);
 940                         error = ENOPROTOOPT;
 941                         break;
 942                 }
 943                 break;
 944         case SOPT_GET:
 945                 switch (sopt->sopt_name) {
 946 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
 947 #ifdef INET
 948                 case UDP_ENCAP:
 949                         if (!IPSEC_ENABLED(ipv4)) {
 950                                 INP_WUNLOCK(inp);
 951                                 return (ENOPROTOOPT);
 952                         }
 953                         error = UDPENCAP_PCBCTL(inp, sopt);
 954                         break;
 955 #endif /* INET */
 956 #endif /* IPSEC */
 957                 case UDPLITE_SEND_CSCOV:
 958                 case UDPLITE_RECV_CSCOV:
 959                         if (!isudplite) {
 960                                 INP_WUNLOCK(inp);
 961                                 error = ENOPROTOOPT;
 962                                 break;
 963                         }
 964                         up = intoudpcb(inp);
 965                         KASSERT(up != NULL, ("%s: up == NULL", __func__));
 966                         if (sopt->sopt_name == UDPLITE_SEND_CSCOV)
 967                                 optval = up->u_txcslen;
 968                         else
 969                                 optval = up->u_rxcslen;
 970                         INP_WUNLOCK(inp);
 971                         error = sooptcopyout(sopt, &optval, sizeof(optval));
 972                         break;
 973                 default:
 974                         INP_WUNLOCK(inp);
 975                         error = ENOPROTOOPT;
 976                         break;
 977                 }
 978                 break;
 979         }
 980         return (error);
 981 }
 982
 983 #ifdef INET
 984 #ifdef INET6
 985 /* The logic here is derived from ip6_setpktopt(). See comments there. */
 986 static int
 987 udp_v4mapped_pktinfo(struct cmsghdr *cm, struct sockaddr_in * src,
 988     struct inpcb *inp, int flags)
 989 {
 990         struct ifnet *ifp;
 991         struct in6_pktinfo *pktinfo;
 992         struct in_addr ia;
 993
 994         if ((flags & PRUS_IPV6) == 0)
 995                 return (0);
 996
 997         if (cm->cmsg_level != IPPROTO_IPV6)
 998                 return (0);
 999
1000         if  (cm->cmsg_type != IPV6_2292PKTINFO &&
1001             cm->cmsg_type != IPV6_PKTINFO)
1002                 return (0);
1003
1004         if (cm->cmsg_len !=
1005             CMSG_LEN(sizeof(struct in6_pktinfo)))
1006                 return (EINVAL);
1007
1008         pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm);
1009         if (!IN6_IS_ADDR_V4MAPPED(&pktinfo->ipi6_addr) &&
1010             !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr))
1011                 return (EINVAL);
1012
1013         /* Validate the interface index if specified. */
1014         if (pktinfo->ipi6_ifindex) {
1015                 struct epoch_tracker et;
1016
1017                 NET_EPOCH_ENTER(et);
1018                 ifp = ifnet_byindex(pktinfo->ipi6_ifindex);
1019                 NET_EPOCH_EXIT(et);     /* XXXGL: unsafe ifp */
1020                 if (ifp == NULL)
1021                         return (ENXIO);
1022         } else
1023                 ifp = NULL;
1024         if (ifp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) {
1025                 ia.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1026                 if (in_ifhasaddr(ifp, ia) == 0)
1027                         return (EADDRNOTAVAIL);
1028         }
1029
1030         bzero(src, sizeof(*src));
1031         src->sin_family = AF_INET;
1032         src->sin_len = sizeof(*src);
1033         src->sin_port = inp->inp_lport;
1034         src->sin_addr.s_addr = pktinfo->ipi6_addr.s6_addr32[3];
1035
1036         return (0);
1037 }
1038 #endif  /* INET6 */
1039
1040 int
1041 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr,
1042     struct mbuf *control, struct thread *td)
1043 {
1044         struct inpcb *inp;
1045         struct udpiphdr *ui;
1046         int len, error = 0;
1047         struct in_addr faddr, laddr;
1048         struct cmsghdr *cm;
1049         struct inpcbinfo *pcbinfo;
1050         struct sockaddr_in *sin, src;
1051         struct epoch_tracker et;
1052         int cscov_partial = 0;
1053         int ipflags = 0;
1054         u_short fport, lport;
1055         u_char tos;
1056         uint8_t pr;
1057         uint16_t cscov = 0;
1058         uint32_t flowid = 0;
1059         uint8_t flowtype = M_HASHTYPE_NONE;
1060
1061         inp = sotoinpcb(so);
1062         KASSERT(inp != NULL, ("udp_send: inp == NULL"));
1063
1064         if (addr != NULL) {
1065                 if (addr->sa_family != AF_INET)
1066                         error = EAFNOSUPPORT;
1067                 else if (addr->sa_len != sizeof(struct sockaddr_in))
1068                         error = EINVAL;
1069                 if (__predict_false(error != 0)) {
1070                         m_freem(control);
1071                         m_freem(m);
1072                         return (error);
1073                 }
1074         }
1075
1076         len = m->m_pkthdr.len;
1077         if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) {
1078                 if (control)
1079                         m_freem(control);
1080                 m_freem(m);
1081                 return (EMSGSIZE);
1082         }
1083
1084         src.sin_family = 0;
1085         sin = (struct sockaddr_in *)addr;
1086
1087         /*
1088          * udp_send() may need to temporarily bind or connect the current
1089          * inpcb.  As such, we don't know up front whether we will need the
1090          * pcbinfo lock or not.  Do any work to decide what is needed up
1091          * front before acquiring any locks.
1092          *
1093          * We will need network epoch in either case, to safely lookup into
1094          * pcb hash.
1095          */
1096         if (sin == NULL ||
1097             (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0))
1098                 INP_WLOCK(inp);
1099         else
1100                 INP_RLOCK(inp);
1101         NET_EPOCH_ENTER(et);
1102         tos = inp->inp_ip_tos;
1103         if (control != NULL) {
1104                 /*
1105                  * XXX: Currently, we assume all the optional information is
1106                  * stored in a single mbuf.
1107                  */
1108                 if (control->m_next) {
1109                         m_freem(control);
1110                         error = EINVAL;
1111                         goto release;
1112                 }
1113                 for (; control->m_len > 0;
1114                     control->m_data += CMSG_ALIGN(cm->cmsg_len),
1115                     control->m_len -= CMSG_ALIGN(cm->cmsg_len)) {
1116                         cm = mtod(control, struct cmsghdr *);
1117                         if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0
1118                             || cm->cmsg_len > control->m_len) {
1119                                 error = EINVAL;
1120                                 break;
1121                         }
1122 #ifdef INET6
1123                         error = udp_v4mapped_pktinfo(cm, &src, inp, flags);
1124                         if (error != 0)
1125                                 break;
1126 #endif
1127                         if (cm->cmsg_level != IPPROTO_IP)
1128                                 continue;
1129
1130                         switch (cm->cmsg_type) {
1131                         case IP_SENDSRCADDR:
1132                                 if (cm->cmsg_len !=
1133                                     CMSG_LEN(sizeof(struct in_addr))) {
1134                                         error = EINVAL;
1135                                         break;
1136                                 }
1137                                 bzero(&src, sizeof(src));
1138                                 src.sin_family = AF_INET;
1139                                 src.sin_len = sizeof(src);
1140                                 src.sin_port = inp->inp_lport;
1141                                 src.sin_addr =
1142                                     *(struct in_addr *)CMSG_DATA(cm);
1143                                 break;
1144
1145                         case IP_TOS:
1146                                 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) {
1147                                         error = EINVAL;
1148                                         break;
1149                                 }
1150                                 tos = *(u_char *)CMSG_DATA(cm);
1151                                 break;
1152
1153                         case IP_FLOWID:
1154                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1155                                         error = EINVAL;
1156                                         break;
1157                                 }
1158                                 flowid = *(uint32_t *) CMSG_DATA(cm);
1159                                 break;
1160
1161                         case IP_FLOWTYPE:
1162                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1163                                         error = EINVAL;
1164                                         break;
1165                                 }
1166                                 flowtype = *(uint32_t *) CMSG_DATA(cm);
1167                                 break;
1168
1169 #ifdef  RSS
1170                         case IP_RSSBUCKETID:
1171                                 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) {
1172                                         error = EINVAL;
1173                                         break;
1174                                 }
1175                                 /* This is just a placeholder for now */
1176                                 break;
1177 #endif  /* RSS */
1178                         default:
1179                                 error = ENOPROTOOPT;
1180                                 break;
1181                         }
1182                         if (error)
1183                                 break;
1184                 }
1185                 m_freem(control);
1186                 control = NULL;
1187         }
1188         if (error)
1189                 goto release;
1190
1191         pr = inp->inp_socket->so_proto->pr_protocol;
1192         pcbinfo = udp_get_inpcbinfo(pr);
1193
1194         /*
1195          * If the IP_SENDSRCADDR control message was specified, override the
1196          * source address for this datagram.  Its use is invalidated if the
1197          * address thus specified is incomplete or clobbers other inpcbs.
1198          */
1199         laddr = inp->inp_laddr;
1200         lport = inp->inp_lport;
1201         if (src.sin_family == AF_INET) {
1202                 if ((lport == 0) ||
1203                     (laddr.s_addr == INADDR_ANY &&
1204                      src.sin_addr.s_addr == INADDR_ANY)) {
1205                         error = EINVAL;
1206                         goto release;
1207                 }
1208                 INP_HASH_WLOCK(pcbinfo);
1209                 error = in_pcbbind_setup(inp, &src, &laddr.s_addr, &lport,
1210                     td->td_ucred);
1211                 INP_HASH_WUNLOCK(pcbinfo);
1212                 if (error)
1213                         goto release;
1214         }
1215
1216         /*
1217          * If a UDP socket has been connected, then a local address/port will
1218          * have been selected and bound.
1219          *
1220          * If a UDP socket has not been connected to, then an explicit
1221          * destination address must be used, in which case a local
1222          * address/port may not have been selected and bound.
1223          */
1224         if (sin != NULL) {
1225                 INP_LOCK_ASSERT(inp);
1226                 if (inp->inp_faddr.s_addr != INADDR_ANY) {
1227                         error = EISCONN;
1228                         goto release;
1229                 }
1230
1231                 /*
1232                  * Jail may rewrite the destination address, so let it do
1233                  * that before we use it.
1234                  */
1235                 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1236                 if (error)
1237                         goto release;
1238
1239                 /*
1240                  * If a local address or port hasn't yet been selected, or if
1241                  * the destination address needs to be rewritten due to using
1242                  * a special INADDR_ constant, invoke in_pcbconnect_setup()
1243                  * to do the heavy lifting.  Once a port is selected, we
1244                  * commit the binding back to the socket; we also commit the
1245                  * binding of the address if in jail.
1246                  *
1247                  * If we already have a valid binding and we're not
1248                  * requesting a destination address rewrite, use a fast path.
1249                  */
1250                 if (inp->inp_laddr.s_addr == INADDR_ANY ||
1251                     inp->inp_lport == 0 ||
1252                     sin->sin_addr.s_addr == INADDR_ANY ||
1253                     sin->sin_addr.s_addr == INADDR_BROADCAST) {
1254                         INP_HASH_WLOCK(pcbinfo);
1255                         error = in_pcbconnect_setup(inp, sin, &laddr.s_addr,
1256                             &lport, &faddr.s_addr, &fport, td->td_ucred);
1257                         if (error) {
1258                                 INP_HASH_WUNLOCK(pcbinfo);
1259                                 goto release;
1260                         }
1261
1262                         /*
1263                          * XXXRW: Why not commit the port if the address is
1264                          * !INADDR_ANY?
1265                          */
1266                         /* Commit the local port if newly assigned. */
1267                         if (inp->inp_laddr.s_addr == INADDR_ANY &&
1268                             inp->inp_lport == 0) {
1269                                 INP_WLOCK_ASSERT(inp);
1270                                 /*
1271                                  * Remember addr if jailed, to prevent
1272                                  * rebinding.
1273                                  */
1274                                 if (prison_flag(td->td_ucred, PR_IP4))
1275                                         inp->inp_laddr = laddr;
1276                                 inp->inp_lport = lport;
1277                                 error = in_pcbinshash(inp);
1278                                 INP_HASH_WUNLOCK(pcbinfo);
1279                                 if (error != 0) {
1280                                         inp->inp_lport = 0;
1281                                         error = EAGAIN;
1282                                         goto release;
1283                                 }
1284                                 inp->inp_flags |= INP_ANONPORT;
1285                         } else
1286                                 INP_HASH_WUNLOCK(pcbinfo);
1287                 } else {
1288                         faddr = sin->sin_addr;
1289                         fport = sin->sin_port;
1290                 }
1291         } else {
1292                 INP_LOCK_ASSERT(inp);
1293                 faddr = inp->inp_faddr;
1294                 fport = inp->inp_fport;
1295                 if (faddr.s_addr == INADDR_ANY) {
1296                         error = ENOTCONN;
1297                         goto release;
1298                 }
1299         }
1300
1301         /*
1302          * Calculate data length and get a mbuf for UDP, IP, and possible
1303          * link-layer headers.  Immediate slide the data pointer back forward
1304          * since we won't use that space at this layer.
1305          */
1306         M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT);
1307         if (m == NULL) {
1308                 error = ENOBUFS;
1309                 goto release;
1310         }
1311         m->m_data += max_linkhdr;
1312         m->m_len -= max_linkhdr;
1313         m->m_pkthdr.len -= max_linkhdr;
1314
1315         /*
1316          * Fill in mbuf with extended UDP header and addresses and length put
1317          * into network format.
1318          */
1319         ui = mtod(m, struct udpiphdr *);
1320         bzero(ui->ui_x1, sizeof(ui->ui_x1));    /* XXX still needed? */
1321         ui->ui_v = IPVERSION << 4;
1322         ui->ui_pr = pr;
1323         ui->ui_src = laddr;
1324         ui->ui_dst = faddr;
1325         ui->ui_sport = lport;
1326         ui->ui_dport = fport;
1327         ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr));
1328         if (pr == IPPROTO_UDPLITE) {
1329                 struct udpcb *up;
1330                 uint16_t plen;
1331
1332                 up = intoudpcb(inp);
1333                 cscov = up->u_txcslen;
1334                 plen = (u_short)len + sizeof(struct udphdr);
1335                 if (cscov >= plen)
1336                         cscov = 0;
1337                 ui->ui_len = htons(plen);
1338                 ui->ui_ulen = htons(cscov);
1339                 /*
1340                  * For UDP-Lite, checksum coverage length of zero means
1341                  * the entire UDPLite packet is covered by the checksum.
1342                  */
1343                 cscov_partial = (cscov == 0) ? 0 : 1;
1344         }
1345
1346         /*
1347          * Set the Don't Fragment bit in the IP header.
1348          */
1349         if (inp->inp_flags & INP_DONTFRAG) {
1350                 struct ip *ip;
1351
1352                 ip = (struct ip *)&ui->ui_i;
1353                 ip->ip_off |= htons(IP_DF);
1354         }
1355
1356         if (inp->inp_socket->so_options & SO_DONTROUTE)
1357                 ipflags |= IP_ROUTETOIF;
1358         if (inp->inp_socket->so_options & SO_BROADCAST)
1359                 ipflags |= IP_ALLOWBROADCAST;
1360         if (inp->inp_flags & INP_ONESBCAST)
1361                 ipflags |= IP_SENDONES;
1362
1363 #ifdef MAC
1364         mac_inpcb_create_mbuf(inp, m);
1365 #endif
1366
1367         /*
1368          * Set up checksum and output datagram.
1369          */
1370         ui->ui_sum = 0;
1371         if (pr == IPPROTO_UDPLITE) {
1372                 if (inp->inp_flags & INP_ONESBCAST)
1373                         faddr.s_addr = INADDR_BROADCAST;
1374                 if (cscov_partial) {
1375                         if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0)
1376                                 ui->ui_sum = 0xffff;
1377                 } else {
1378                         if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0)
1379                                 ui->ui_sum = 0xffff;
1380                 }
1381         } else if (V_udp_cksum) {
1382                 if (inp->inp_flags & INP_ONESBCAST)
1383                         faddr.s_addr = INADDR_BROADCAST;
1384                 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr,
1385                     htons((u_short)len + sizeof(struct udphdr) + pr));
1386                 m->m_pkthdr.csum_flags = CSUM_UDP;
1387                 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
1388         }
1389         ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len);
1390         ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl;    /* XXX */
1391         ((struct ip *)ui)->ip_tos = tos;                /* XXX */
1392         UDPSTAT_INC(udps_opackets);
1393
1394         /*
1395          * Setup flowid / RSS information for outbound socket.
1396          *
1397          * Once the UDP code decides to set a flowid some other way,
1398          * this allows the flowid to be overridden by userland.
1399          */
1400         if (flowtype != M_HASHTYPE_NONE) {
1401                 m->m_pkthdr.flowid = flowid;
1402                 M_HASHTYPE_SET(m, flowtype);
1403         }
1404 #if defined(ROUTE_MPATH) || defined(RSS)
1405         else if (CALC_FLOWID_OUTBOUND_SENDTO) {
1406                 uint32_t hash_val, hash_type;
1407
1408                 hash_val = fib4_calc_packet_hash(laddr, faddr,
1409                     lport, fport, pr, &hash_type);
1410                 m->m_pkthdr.flowid = hash_val;
1411                 M_HASHTYPE_SET(m, hash_type);
1412         }
1413
1414         /*
1415          * Don't override with the inp cached flowid value.
1416          *
1417          * Depending upon the kind of send being done, the inp
1418          * flowid/flowtype values may actually not be appropriate
1419          * for this particular socket send.
1420          *
1421          * We should either leave the flowid at zero (which is what is
1422          * currently done) or set it to some software generated
1423          * hash value based on the packet contents.
1424          */
1425         ipflags |= IP_NODEFAULTFLOWID;
1426 #endif  /* RSS */
1427
1428         if (pr == IPPROTO_UDPLITE)
1429                 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1430         else
1431                 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u);
1432         error = ip_output(m, inp->inp_options,
1433             INP_WLOCKED(inp) ? &inp->inp_route : NULL, ipflags,
1434             inp->inp_moptions, inp);
1435         INP_UNLOCK(inp);
1436         NET_EPOCH_EXIT(et);
1437         return (error);
1438
1439 release:
1440         INP_UNLOCK(inp);
1441         NET_EPOCH_EXIT(et);
1442         m_freem(m);
1443         return (error);
1444 }
1445
1446 void
1447 udp_abort(struct socket *so)
1448 {
1449         struct inpcb *inp;
1450         struct inpcbinfo *pcbinfo;
1451
1452         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1453         inp = sotoinpcb(so);
1454         KASSERT(inp != NULL, ("udp_abort: inp == NULL"));
1455         INP_WLOCK(inp);
1456         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1457                 INP_HASH_WLOCK(pcbinfo);
1458                 in_pcbdisconnect(inp);
1459                 INP_HASH_WUNLOCK(pcbinfo);
1460                 soisdisconnected(so);
1461         }
1462         INP_WUNLOCK(inp);
1463 }
1464
1465 static int
1466 udp_attach(struct socket *so, int proto, struct thread *td)
1467 {
1468         static uint32_t udp_flowid;
1469         struct inpcbinfo *pcbinfo;
1470         struct inpcb *inp;
1471         struct udpcb *up;
1472         int error;
1473
1474         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1475         inp = sotoinpcb(so);
1476         KASSERT(inp == NULL, ("udp_attach: inp != NULL"));
1477         error = soreserve(so, udp_sendspace, udp_recvspace);
1478         if (error)
1479                 return (error);
1480         error = in_pcballoc(so, pcbinfo);
1481         if (error)
1482                 return (error);
1483
1484         inp = sotoinpcb(so);
1485         inp->inp_ip_ttl = V_ip_defttl;
1486         inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1);
1487         inp->inp_flowtype = M_HASHTYPE_OPAQUE;
1488         up = intoudpcb(inp);
1489         bzero(&up->u_start_zero, u_zero_size);
1490         INP_WUNLOCK(inp);
1491
1492         return (0);
1493 }
1494 #endif /* INET */
1495
1496 int
1497 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx)
1498 {
1499         struct inpcb *inp;
1500         struct udpcb *up;
1501
1502         KASSERT(so->so_type == SOCK_DGRAM,
1503             ("udp_set_kernel_tunneling: !dgram"));
1504         inp = sotoinpcb(so);
1505         KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL"));
1506         INP_WLOCK(inp);
1507         up = intoudpcb(inp);
1508         if ((f != NULL || i != NULL) && ((up->u_tun_func != NULL) ||
1509             (up->u_icmp_func != NULL))) {
1510                 INP_WUNLOCK(inp);
1511                 return (EBUSY);
1512         }
1513         up->u_tun_func = f;
1514         up->u_icmp_func = i;
1515         up->u_tun_ctx = ctx;
1516         INP_WUNLOCK(inp);
1517         return (0);
1518 }
1519
1520 #ifdef INET
1521 static int
1522 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1523 {
1524         struct inpcb *inp;
1525         struct inpcbinfo *pcbinfo;
1526         struct sockaddr_in *sinp;
1527         int error;
1528
1529         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1530         inp = sotoinpcb(so);
1531         KASSERT(inp != NULL, ("udp_bind: inp == NULL"));
1532
1533         sinp = (struct sockaddr_in *)nam;
1534         if (nam->sa_family != AF_INET) {
1535                 /*
1536                  * Preserve compatibility with old programs.
1537                  */
1538                 if (nam->sa_family != AF_UNSPEC ||
1539                     nam->sa_len < offsetof(struct sockaddr_in, sin_zero) ||
1540                     sinp->sin_addr.s_addr != INADDR_ANY)
1541                         return (EAFNOSUPPORT);
1542                 nam->sa_family = AF_INET;
1543         }
1544         if (nam->sa_len != sizeof(struct sockaddr_in))
1545                 return (EINVAL);
1546
1547         INP_WLOCK(inp);
1548         INP_HASH_WLOCK(pcbinfo);
1549         error = in_pcbbind(inp, sinp, td->td_ucred);
1550         INP_HASH_WUNLOCK(pcbinfo);
1551         INP_WUNLOCK(inp);
1552         return (error);
1553 }
1554
1555 static void
1556 udp_close(struct socket *so)
1557 {
1558         struct inpcb *inp;
1559         struct inpcbinfo *pcbinfo;
1560
1561         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1562         inp = sotoinpcb(so);
1563         KASSERT(inp != NULL, ("udp_close: inp == NULL"));
1564         INP_WLOCK(inp);
1565         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1566                 INP_HASH_WLOCK(pcbinfo);
1567                 in_pcbdisconnect(inp);
1568                 INP_HASH_WUNLOCK(pcbinfo);
1569                 soisdisconnected(so);
1570         }
1571         INP_WUNLOCK(inp);
1572 }
1573
1574 static int
1575 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1576 {
1577         struct epoch_tracker et;
1578         struct inpcb *inp;
1579         struct inpcbinfo *pcbinfo;
1580         struct sockaddr_in *sin;
1581         int error;
1582
1583         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1584         inp = sotoinpcb(so);
1585         KASSERT(inp != NULL, ("udp_connect: inp == NULL"));
1586
1587         sin = (struct sockaddr_in *)nam;
1588         if (sin->sin_family != AF_INET)
1589                 return (EAFNOSUPPORT);
1590         if (sin->sin_len != sizeof(*sin))
1591                 return (EINVAL);
1592
1593         INP_WLOCK(inp);
1594         if (inp->inp_faddr.s_addr != INADDR_ANY) {
1595                 INP_WUNLOCK(inp);
1596                 return (EISCONN);
1597         }
1598         error = prison_remote_ip4(td->td_ucred, &sin->sin_addr);
1599         if (error != 0) {
1600                 INP_WUNLOCK(inp);
1601                 return (error);
1602         }
1603         NET_EPOCH_ENTER(et);
1604         INP_HASH_WLOCK(pcbinfo);
1605         error = in_pcbconnect(inp, sin, td->td_ucred, true);
1606         INP_HASH_WUNLOCK(pcbinfo);
1607         NET_EPOCH_EXIT(et);
1608         if (error == 0)
1609                 soisconnected(so);
1610         INP_WUNLOCK(inp);
1611         return (error);
1612 }
1613
1614 static void
1615 udp_detach(struct socket *so)
1616 {
1617         struct inpcb *inp;
1618
1619         inp = sotoinpcb(so);
1620         KASSERT(inp != NULL, ("udp_detach: inp == NULL"));
1621         KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
1622             ("udp_detach: not disconnected"));
1623         INP_WLOCK(inp);
1624         in_pcbdetach(inp);
1625         in_pcbfree(inp);
1626 }
1627
1628 int
1629 udp_disconnect(struct socket *so)
1630 {
1631         struct inpcb *inp;
1632         struct inpcbinfo *pcbinfo;
1633
1634         pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol);
1635         inp = sotoinpcb(so);
1636         KASSERT(inp != NULL, ("udp_disconnect: inp == NULL"));
1637         INP_WLOCK(inp);
1638         if (inp->inp_faddr.s_addr == INADDR_ANY) {
1639                 INP_WUNLOCK(inp);
1640                 return (ENOTCONN);
1641         }
1642         INP_HASH_WLOCK(pcbinfo);
1643         in_pcbdisconnect(inp);
1644         INP_HASH_WUNLOCK(pcbinfo);
1645         SOCK_LOCK(so);
1646         so->so_state &= ~SS_ISCONNECTED;                /* XXX */
1647         SOCK_UNLOCK(so);
1648         INP_WUNLOCK(inp);
1649         return (0);
1650 }
1651 #endif /* INET */
1652
1653 int
1654 udp_shutdown(struct socket *so)
1655 {
1656         struct inpcb *inp;
1657
1658         inp = sotoinpcb(so);
1659         KASSERT(inp != NULL, ("udp_shutdown: inp == NULL"));
1660         INP_WLOCK(inp);
1661         socantsendmore(so);
1662         INP_WUNLOCK(inp);
1663         return (0);
1664 }
1665
1666 #ifdef INET
1667 #define UDP_PROTOSW                                                     \
1668         .pr_type =              SOCK_DGRAM,                             \
1669         .pr_flags =             PR_ATOMIC | PR_ADDR | PR_CAPATTACH,     \
1670         .pr_ctloutput =         udp_ctloutput,                          \
1671         .pr_abort =             udp_abort,                              \
1672         .pr_attach =            udp_attach,                             \
1673         .pr_bind =              udp_bind,                               \
1674         .pr_connect =           udp_connect,                            \
1675         .pr_control =           in_control,                             \
1676         .pr_detach =            udp_detach,                             \
1677         .pr_disconnect =        udp_disconnect,                         \
1678         .pr_peeraddr =          in_getpeeraddr,                         \
1679         .pr_send =              udp_send,                               \
1680         .pr_soreceive =         soreceive_dgram,                        \
1681         .pr_sosend =            sosend_dgram,                           \
1682         .pr_shutdown =          udp_shutdown,                           \
1683         .pr_sockaddr =          in_getsockaddr,                         \
1684         .pr_sosetlabel =        in_pcbsosetlabel,                       \
1685         .pr_close =             udp_close
1686
1687 struct protosw udp_protosw = {
1688         .pr_protocol =          IPPROTO_UDP,
1689         UDP_PROTOSW
1690 };
1691
1692 struct protosw udplite_protosw = {
1693         .pr_protocol =          IPPROTO_UDPLITE,
1694         UDP_PROTOSW
1695 };
1696
1697 static void
1698 udp_init(void *arg __unused)
1699 {
1700
1701         IPPROTO_REGISTER(IPPROTO_UDP, udp_input, udp_ctlinput);
1702         IPPROTO_REGISTER(IPPROTO_UDPLITE, udp_input, udplite_ctlinput);
1703 }
1704 SYSINIT(udp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, udp_init, NULL);
1705 #endif /* INET */