1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 3 * The Regents of the University of California. 4 * Copyright (c) 2008 Robert N. M. Watson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 4. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_ipfw.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 41 #include <sys/param.h> 42 #include <sys/domain.h> 43 #include <sys/eventhandler.h> 44 #include <sys/jail.h> 45 #include <sys/kernel.h> 46 #include <sys/lock.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #include <sys/priv.h> 50 #include <sys/proc.h> 51 #include <sys/protosw.h> 52 #include <sys/signalvar.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 #include <sys/sx.h> 56 #include <sys/sysctl.h> 57 #include <sys/syslog.h> 58 #include <sys/systm.h> 59 60 #include <vm/uma.h> 61 62 #include <net/if.h> 63 #include <net/route.h> 64 65 #include <netinet/in.h> 66 #include <netinet/in_pcb.h> 67 #include <netinet/in_systm.h> 68 #include <netinet/in_var.h> 69 #include <netinet/ip.h> 70 #ifdef INET6 71 #include <netinet/ip6.h> 72 #endif 73 #include <netinet/ip_icmp.h> 74 #include <netinet/icmp_var.h> 75 #include <netinet/ip_var.h> 76 #include <netinet/ip_options.h> 77 #ifdef INET6 78 #include <netinet6/ip6_var.h> 79 #endif 80 #include <netinet/udp.h> 81 #include <netinet/udp_var.h> 82 83 #ifdef IPSEC 84 #include <netipsec/ipsec.h> 85 #include <netipsec/esp.h> 86 #endif 87 88 #include <machine/in_cksum.h> 89 90 #include <security/mac/mac_framework.h> 91 92 /* 93 * UDP protocol implementation. 94 * Per RFC 768, August, 1980. 95 */ 96 97 VNET_DEFINE(int, udp_blackhole); 98 99 /* 100 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums 101 * removes the only data integrity mechanism for packets and malformed 102 * packets that would otherwise be discarded due to bad checksums, and may 103 * cause problems (especially for NFS data blocks). 104 */ 105 static int udp_cksum = 1; 106 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, &udp_cksum, 107 0, "compute udp checksum"); 108 109 int udp_log_in_vain = 0; 110 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW, 111 &udp_log_in_vain, 0, "Log all incoming UDP packets"); 112 113 SYSCTL_VNET_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW, 114 &VNET_NAME(udp_blackhole), 0, 115 "Do not send port unreachables for refused connects"); 116 117 u_long udp_sendspace = 9216; /* really max datagram size */ 118 /* 40 1K datagrams */ 119 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 120 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 121 122 u_long udp_recvspace = 40 * (1024 + 123 #ifdef INET6 124 sizeof(struct sockaddr_in6) 125 #else 126 sizeof(struct sockaddr_in) 127 #endif 128 ); 129 130 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 131 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 132 133 VNET_DEFINE(struct inpcbhead, udb); /* from udp_var.h */ 134 VNET_DEFINE(struct inpcbinfo, udbinfo); 135 static VNET_DEFINE(uma_zone_t, udpcb_zone); 136 VNET_DEFINE(struct udpstat, udpstat); /* from udp_var.h */ 137 138 #define V_udpcb_zone VNET(udpcb_zone) 139 140 #ifndef UDBHASHSIZE 141 #define UDBHASHSIZE 128 142 #endif 143 144 SYSCTL_VNET_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW, 145 &VNET_NAME(udpstat), udpstat, 146 "UDP statistics (struct udpstat, netinet/udp_var.h)"); 147 148 static void udp_detach(struct socket *so); 149 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 150 struct mbuf *, struct thread *); 151 #ifdef IPSEC 152 #ifdef IPSEC_NAT_T 153 #define UF_ESPINUDP_ALL (UF_ESPINUDP_NON_IKE|UF_ESPINUDP) 154 #ifdef INET 155 static struct mbuf *udp4_espdecap(struct inpcb *, struct mbuf *, int); 156 #endif 157 #endif /* IPSEC_NAT_T */ 158 #endif /* IPSEC */ 159 160 static void 161 udp_zone_change(void *tag) 162 { 163 164 uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets); 165 uma_zone_set_max(V_udpcb_zone, maxsockets); 166 } 167 168 static int 169 udp_inpcb_init(void *mem, int size, int flags) 170 { 171 struct inpcb *inp; 172 173 inp = mem; 174 INP_LOCK_INIT(inp, "inp", "udpinp"); 175 return (0); 176 } 177 178 void 179 udp_init(void) 180 { 181 182 V_udp_blackhole = 0; 183 in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE, 184 "udp_inpcb", udp_inpcb_init, NULL, UMA_ZONE_NOFREE); 185 V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb), 186 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 187 uma_zone_set_max(V_udpcb_zone, maxsockets); 188 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL, 189 EVENTHANDLER_PRI_ANY); 190 } 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 (*((u_long *)&V_udpstat + statnum))++; 204 } 205 206 int 207 udp_newudpcb(struct inpcb *inp) 208 { 209 struct udpcb *up; 210 211 up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO); 212 if (up == NULL) 213 return (ENOBUFS); 214 inp->inp_ppcb = up; 215 return (0); 216 } 217 218 void 219 udp_discardcb(struct udpcb *up) 220 { 221 222 uma_zfree(V_udpcb_zone, up); 223 } 224 225 #ifdef VIMAGE 226 void 227 udp_destroy(void) 228 { 229 230 in_pcbinfo_destroy(&V_udbinfo); 231 uma_zdestroy(V_udpcb_zone); 232 } 233 #endif 234 235 /* 236 * Subroutine of udp_input(), which appends the provided mbuf chain to the 237 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 238 * contains the source address. If the socket ends up being an IPv6 socket, 239 * udp_append() will convert to a sockaddr_in6 before passing the address 240 * into the socket code. 241 */ 242 static void 243 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off, 244 struct sockaddr_in *udp_in) 245 { 246 struct sockaddr *append_sa; 247 struct socket *so; 248 struct mbuf *opts = 0; 249 #ifdef INET6 250 struct sockaddr_in6 udp_in6; 251 #endif 252 #ifdef IPSEC 253 #ifdef IPSEC_NAT_T 254 #ifdef INET 255 struct udpcb *up; 256 #endif 257 #endif 258 #endif 259 260 INP_RLOCK_ASSERT(inp); 261 262 #ifdef IPSEC 263 /* Check AH/ESP integrity. */ 264 if (ipsec4_in_reject(n, inp)) { 265 m_freem(n); 266 V_ipsec4stat.in_polvio++; 267 return; 268 } 269 #ifdef IPSEC_NAT_T 270 #ifdef INET 271 up = intoudpcb(inp); 272 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 273 if (up->u_flags & UF_ESPINUDP_ALL) { /* IPSec UDP encaps. */ 274 n = udp4_espdecap(inp, n, off); 275 if (n == NULL) /* Consumed. */ 276 return; 277 } 278 #endif /* INET */ 279 #endif /* IPSEC_NAT_T */ 280 #endif /* IPSEC */ 281 #ifdef MAC 282 if (mac_inpcb_check_deliver(inp, n) != 0) { 283 m_freem(n); 284 return; 285 } 286 #endif 287 if (inp->inp_flags & INP_CONTROLOPTS || 288 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 289 #ifdef INET6 290 if (inp->inp_vflag & INP_IPV6) 291 (void)ip6_savecontrol_v4(inp, n, &opts, NULL); 292 else 293 #endif 294 ip_savecontrol(inp, &opts, ip, n); 295 } 296 #ifdef INET6 297 if (inp->inp_vflag & INP_IPV6) { 298 bzero(&udp_in6, sizeof(udp_in6)); 299 udp_in6.sin6_len = sizeof(udp_in6); 300 udp_in6.sin6_family = AF_INET6; 301 in6_sin_2_v4mapsin6(udp_in, &udp_in6); 302 append_sa = (struct sockaddr *)&udp_in6; 303 } else 304 #endif 305 append_sa = (struct sockaddr *)udp_in; 306 m_adj(n, off); 307 308 so = inp->inp_socket; 309 SOCKBUF_LOCK(&so->so_rcv); 310 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 311 SOCKBUF_UNLOCK(&so->so_rcv); 312 m_freem(n); 313 if (opts) 314 m_freem(opts); 315 UDPSTAT_INC(udps_fullsock); 316 } else 317 sorwakeup_locked(so); 318 } 319 320 void 321 udp_input(struct mbuf *m, int off) 322 { 323 int iphlen = off; 324 struct ip *ip; 325 struct udphdr *uh; 326 struct ifnet *ifp; 327 struct inpcb *inp; 328 struct udpcb *up; 329 int len; 330 struct ip save_ip; 331 struct sockaddr_in udp_in; 332 #ifdef IPFIREWALL_FORWARD 333 struct m_tag *fwd_tag; 334 #endif 335 336 ifp = m->m_pkthdr.rcvif; 337 UDPSTAT_INC(udps_ipackets); 338 339 /* 340 * Strip IP options, if any; should skip this, make available to 341 * user, and use on returned packets, but we don't yet have a way to 342 * check the checksum with options still present. 343 */ 344 if (iphlen > sizeof (struct ip)) { 345 ip_stripoptions(m, (struct mbuf *)0); 346 iphlen = sizeof(struct ip); 347 } 348 349 /* 350 * Get IP and UDP header together in first mbuf. 351 */ 352 ip = mtod(m, struct ip *); 353 if (m->m_len < iphlen + sizeof(struct udphdr)) { 354 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 355 UDPSTAT_INC(udps_hdrops); 356 return; 357 } 358 ip = mtod(m, struct ip *); 359 } 360 uh = (struct udphdr *)((caddr_t)ip + iphlen); 361 362 /* 363 * Destination port of 0 is illegal, based on RFC768. 364 */ 365 if (uh->uh_dport == 0) 366 goto badunlocked; 367 368 /* 369 * Construct sockaddr format source address. Stuff source address 370 * and datagram in user buffer. 371 */ 372 bzero(&udp_in, sizeof(udp_in)); 373 udp_in.sin_len = sizeof(udp_in); 374 udp_in.sin_family = AF_INET; 375 udp_in.sin_port = uh->uh_sport; 376 udp_in.sin_addr = ip->ip_src; 377 378 /* 379 * Make mbuf data length reflect UDP length. If not enough data to 380 * reflect UDP length, drop. 381 */ 382 len = ntohs((u_short)uh->uh_ulen); 383 if (ip->ip_len != len) { 384 if (len > ip->ip_len || len < sizeof(struct udphdr)) { 385 UDPSTAT_INC(udps_badlen); 386 goto badunlocked; 387 } 388 m_adj(m, len - ip->ip_len); 389 /* ip->ip_len = len; */ 390 } 391 392 /* 393 * Save a copy of the IP header in case we want restore it for 394 * sending an ICMP error message in response. 395 */ 396 if (!V_udp_blackhole) 397 save_ip = *ip; 398 else 399 memset(&save_ip, 0, sizeof(save_ip)); 400 401 /* 402 * Checksum extended UDP header and data. 403 */ 404 if (uh->uh_sum) { 405 u_short uh_sum; 406 407 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 408 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 409 uh_sum = m->m_pkthdr.csum_data; 410 else 411 uh_sum = in_pseudo(ip->ip_src.s_addr, 412 ip->ip_dst.s_addr, htonl((u_short)len + 413 m->m_pkthdr.csum_data + IPPROTO_UDP)); 414 uh_sum ^= 0xffff; 415 } else { 416 char b[9]; 417 418 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 419 bzero(((struct ipovly *)ip)->ih_x1, 9); 420 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 421 uh_sum = in_cksum(m, len + sizeof (struct ip)); 422 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 423 } 424 if (uh_sum) { 425 UDPSTAT_INC(udps_badsum); 426 m_freem(m); 427 return; 428 } 429 } else 430 UDPSTAT_INC(udps_nosum); 431 432 #ifdef IPFIREWALL_FORWARD 433 /* 434 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. 435 */ 436 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 437 if (fwd_tag != NULL) { 438 struct sockaddr_in *next_hop; 439 440 /* 441 * Do the hack. 442 */ 443 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 444 ip->ip_dst = next_hop->sin_addr; 445 uh->uh_dport = ntohs(next_hop->sin_port); 446 447 /* 448 * Remove the tag from the packet. We don't need it anymore. 449 */ 450 m_tag_delete(m, fwd_tag); 451 } 452 #endif 453 454 INP_INFO_RLOCK(&V_udbinfo); 455 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 456 in_broadcast(ip->ip_dst, ifp)) { 457 struct inpcb *last; 458 struct ip_moptions *imo; 459 460 last = NULL; 461 LIST_FOREACH(inp, &V_udb, inp_list) { 462 if (inp->inp_lport != uh->uh_dport) 463 continue; 464 #ifdef INET6 465 if ((inp->inp_vflag & INP_IPV4) == 0) 466 continue; 467 #endif 468 if (inp->inp_laddr.s_addr != INADDR_ANY && 469 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 470 continue; 471 if (inp->inp_faddr.s_addr != INADDR_ANY && 472 inp->inp_faddr.s_addr != ip->ip_src.s_addr) 473 continue; 474 if (inp->inp_fport != 0 && 475 inp->inp_fport != uh->uh_sport) 476 continue; 477 478 INP_RLOCK(inp); 479 480 /* 481 * Handle socket delivery policy for any-source 482 * and source-specific multicast. [RFC3678] 483 */ 484 imo = inp->inp_moptions; 485 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) && 486 imo != NULL) { 487 struct sockaddr_in group; 488 int blocked; 489 490 bzero(&group, sizeof(struct sockaddr_in)); 491 group.sin_len = sizeof(struct sockaddr_in); 492 group.sin_family = AF_INET; 493 group.sin_addr = ip->ip_dst; 494 495 blocked = imo_multi_filter(imo, ifp, 496 (struct sockaddr *)&group, 497 (struct sockaddr *)&udp_in); 498 if (blocked != MCAST_PASS) { 499 if (blocked == MCAST_NOTGMEMBER) 500 IPSTAT_INC(ips_notmember); 501 if (blocked == MCAST_NOTSMEMBER || 502 blocked == MCAST_MUTED) 503 UDPSTAT_INC(udps_filtermcast); 504 INP_RUNLOCK(inp); 505 continue; 506 } 507 } 508 if (last != NULL) { 509 struct mbuf *n; 510 511 n = m_copy(m, 0, M_COPYALL); 512 up = intoudpcb(last); 513 if (up->u_tun_func == NULL) { 514 if (n != NULL) 515 udp_append(last, 516 ip, n, 517 iphlen + 518 sizeof(struct udphdr), 519 &udp_in); 520 } else { 521 /* 522 * Engage the tunneling protocol we 523 * will have to leave the info_lock 524 * up, since we are hunting through 525 * multiple UDP's. 526 */ 527 528 (*up->u_tun_func)(n, iphlen, last); 529 } 530 INP_RUNLOCK(last); 531 } 532 last = inp; 533 /* 534 * Don't look for additional matches if this one does 535 * not have either the SO_REUSEPORT or SO_REUSEADDR 536 * socket options set. This heuristic avoids 537 * searching through all pcbs in the common case of a 538 * non-shared port. It assumes that an application 539 * will never clear these options after setting them. 540 */ 541 if ((last->inp_socket->so_options & 542 (SO_REUSEPORT|SO_REUSEADDR)) == 0) 543 break; 544 } 545 546 if (last == NULL) { 547 /* 548 * No matching pcb found; discard datagram. (No need 549 * to send an ICMP Port Unreachable for a broadcast 550 * or multicast datgram.) 551 */ 552 UDPSTAT_INC(udps_noportbcast); 553 goto badheadlocked; 554 } 555 up = intoudpcb(last); 556 if (up->u_tun_func == NULL) { 557 udp_append(last, ip, m, iphlen + sizeof(struct udphdr), 558 &udp_in); 559 } else { 560 /* 561 * Engage the tunneling protocol. 562 */ 563 (*up->u_tun_func)(m, iphlen, last); 564 } 565 INP_RUNLOCK(last); 566 INP_INFO_RUNLOCK(&V_udbinfo); 567 return; 568 } 569 570 /* 571 * Locate pcb for datagram. 572 */ 573 inp = in_pcblookup_hash(&V_udbinfo, ip->ip_src, uh->uh_sport, 574 ip->ip_dst, uh->uh_dport, 1, ifp); 575 if (inp == NULL) { 576 if (udp_log_in_vain) { 577 char buf[4*sizeof "123"]; 578 579 strcpy(buf, inet_ntoa(ip->ip_dst)); 580 log(LOG_INFO, 581 "Connection attempt to UDP %s:%d from %s:%d\n", 582 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 583 ntohs(uh->uh_sport)); 584 } 585 UDPSTAT_INC(udps_noport); 586 if (m->m_flags & (M_BCAST | M_MCAST)) { 587 UDPSTAT_INC(udps_noportbcast); 588 goto badheadlocked; 589 } 590 if (V_udp_blackhole) 591 goto badheadlocked; 592 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 593 goto badheadlocked; 594 *ip = save_ip; 595 ip->ip_len += iphlen; 596 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 597 INP_INFO_RUNLOCK(&V_udbinfo); 598 return; 599 } 600 601 /* 602 * Check the minimum TTL for socket. 603 */ 604 INP_RLOCK(inp); 605 INP_INFO_RUNLOCK(&V_udbinfo); 606 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) { 607 INP_RUNLOCK(inp); 608 goto badunlocked; 609 } 610 up = intoudpcb(inp); 611 if (up->u_tun_func == NULL) { 612 udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in); 613 } else { 614 /* 615 * Engage the tunneling protocol. 616 */ 617 618 (*up->u_tun_func)(m, iphlen, inp); 619 } 620 INP_RUNLOCK(inp); 621 return; 622 623 badheadlocked: 624 if (inp) 625 INP_RUNLOCK(inp); 626 INP_INFO_RUNLOCK(&V_udbinfo); 627 badunlocked: 628 m_freem(m); 629 } 630 631 /* 632 * Notify a udp user of an asynchronous error; just wake up so that they can 633 * collect error status. 634 */ 635 struct inpcb * 636 udp_notify(struct inpcb *inp, int errno) 637 { 638 639 /* 640 * While udp_ctlinput() always calls udp_notify() with a read lock 641 * when invoking it directly, in_pcbnotifyall() currently uses write 642 * locks due to sharing code with TCP. For now, accept either a read 643 * or a write lock, but a read lock is sufficient. 644 */ 645 INP_LOCK_ASSERT(inp); 646 647 inp->inp_socket->so_error = errno; 648 sorwakeup(inp->inp_socket); 649 sowwakeup(inp->inp_socket); 650 return (inp); 651 } 652 653 void 654 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 655 { 656 struct ip *ip = vip; 657 struct udphdr *uh; 658 struct in_addr faddr; 659 struct inpcb *inp; 660 661 faddr = ((struct sockaddr_in *)sa)->sin_addr; 662 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 663 return; 664 665 /* 666 * Redirects don't need to be handled up here. 667 */ 668 if (PRC_IS_REDIRECT(cmd)) 669 return; 670 671 /* 672 * Hostdead is ugly because it goes linearly through all PCBs. 673 * 674 * XXX: We never get this from ICMP, otherwise it makes an excellent 675 * DoS attack on machines with many connections. 676 */ 677 if (cmd == PRC_HOSTDEAD) 678 ip = NULL; 679 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 680 return; 681 if (ip != NULL) { 682 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 683 INP_INFO_RLOCK(&V_udbinfo); 684 inp = in_pcblookup_hash(&V_udbinfo, faddr, uh->uh_dport, 685 ip->ip_src, uh->uh_sport, 0, NULL); 686 if (inp != NULL) { 687 INP_RLOCK(inp); 688 if (inp->inp_socket != NULL) { 689 udp_notify(inp, inetctlerrmap[cmd]); 690 } 691 INP_RUNLOCK(inp); 692 } 693 INP_INFO_RUNLOCK(&V_udbinfo); 694 } else 695 in_pcbnotifyall(&V_udbinfo, faddr, inetctlerrmap[cmd], 696 udp_notify); 697 } 698 699 static int 700 udp_pcblist(SYSCTL_HANDLER_ARGS) 701 { 702 int error, i, n; 703 struct inpcb *inp, **inp_list; 704 inp_gen_t gencnt; 705 struct xinpgen xig; 706 707 /* 708 * The process of preparing the PCB list is too time-consuming and 709 * resource-intensive to repeat twice on every request. 710 */ 711 if (req->oldptr == 0) { 712 n = V_udbinfo.ipi_count; 713 req->oldidx = 2 * (sizeof xig) 714 + (n + n/8) * sizeof(struct xinpcb); 715 return (0); 716 } 717 718 if (req->newptr != 0) 719 return (EPERM); 720 721 /* 722 * OK, now we're committed to doing something. 723 */ 724 INP_INFO_RLOCK(&V_udbinfo); 725 gencnt = V_udbinfo.ipi_gencnt; 726 n = V_udbinfo.ipi_count; 727 INP_INFO_RUNLOCK(&V_udbinfo); 728 729 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 730 + n * sizeof(struct xinpcb)); 731 if (error != 0) 732 return (error); 733 734 xig.xig_len = sizeof xig; 735 xig.xig_count = n; 736 xig.xig_gen = gencnt; 737 xig.xig_sogen = so_gencnt; 738 error = SYSCTL_OUT(req, &xig, sizeof xig); 739 if (error) 740 return (error); 741 742 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 743 if (inp_list == 0) 744 return (ENOMEM); 745 746 INP_INFO_RLOCK(&V_udbinfo); 747 for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n; 748 inp = LIST_NEXT(inp, inp_list)) { 749 INP_WLOCK(inp); 750 if (inp->inp_gencnt <= gencnt && 751 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 752 in_pcbref(inp); 753 inp_list[i++] = inp; 754 } 755 INP_WUNLOCK(inp); 756 } 757 INP_INFO_RUNLOCK(&V_udbinfo); 758 n = i; 759 760 error = 0; 761 for (i = 0; i < n; i++) { 762 inp = inp_list[i]; 763 INP_RLOCK(inp); 764 if (inp->inp_gencnt <= gencnt) { 765 struct xinpcb xi; 766 767 bzero(&xi, sizeof(xi)); 768 xi.xi_len = sizeof xi; 769 /* XXX should avoid extra copy */ 770 bcopy(inp, &xi.xi_inp, sizeof *inp); 771 if (inp->inp_socket) 772 sotoxsocket(inp->inp_socket, &xi.xi_socket); 773 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 774 INP_RUNLOCK(inp); 775 error = SYSCTL_OUT(req, &xi, sizeof xi); 776 } else 777 INP_RUNLOCK(inp); 778 } 779 INP_INFO_WLOCK(&V_udbinfo); 780 for (i = 0; i < n; i++) { 781 inp = inp_list[i]; 782 INP_WLOCK(inp); 783 if (!in_pcbrele(inp)) 784 INP_WUNLOCK(inp); 785 } 786 INP_INFO_WUNLOCK(&V_udbinfo); 787 788 if (!error) { 789 /* 790 * Give the user an updated idea of our state. If the 791 * generation differs from what we told her before, she knows 792 * that something happened while we were processing this 793 * request, and it might be necessary to retry. 794 */ 795 INP_INFO_RLOCK(&V_udbinfo); 796 xig.xig_gen = V_udbinfo.ipi_gencnt; 797 xig.xig_sogen = so_gencnt; 798 xig.xig_count = V_udbinfo.ipi_count; 799 INP_INFO_RUNLOCK(&V_udbinfo); 800 error = SYSCTL_OUT(req, &xig, sizeof xig); 801 } 802 free(inp_list, M_TEMP); 803 return (error); 804 } 805 806 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 807 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 808 809 static int 810 udp_getcred(SYSCTL_HANDLER_ARGS) 811 { 812 struct xucred xuc; 813 struct sockaddr_in addrs[2]; 814 struct inpcb *inp; 815 int error; 816 817 error = priv_check(req->td, PRIV_NETINET_GETCRED); 818 if (error) 819 return (error); 820 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 821 if (error) 822 return (error); 823 INP_INFO_RLOCK(&V_udbinfo); 824 inp = in_pcblookup_hash(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 825 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL); 826 if (inp != NULL) { 827 INP_RLOCK(inp); 828 INP_INFO_RUNLOCK(&V_udbinfo); 829 if (inp->inp_socket == NULL) 830 error = ENOENT; 831 if (error == 0) 832 error = cr_canseeinpcb(req->td->td_ucred, inp); 833 if (error == 0) 834 cru2x(inp->inp_cred, &xuc); 835 INP_RUNLOCK(inp); 836 } else { 837 INP_INFO_RUNLOCK(&V_udbinfo); 838 error = ENOENT; 839 } 840 if (error == 0) 841 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 842 return (error); 843 } 844 845 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 846 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 847 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 848 849 int 850 udp_ctloutput(struct socket *so, struct sockopt *sopt) 851 { 852 int error = 0, optval; 853 struct inpcb *inp; 854 #ifdef IPSEC_NAT_T 855 struct udpcb *up; 856 #endif 857 858 inp = sotoinpcb(so); 859 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 860 INP_WLOCK(inp); 861 if (sopt->sopt_level != IPPROTO_UDP) { 862 #ifdef INET6 863 if (INP_CHECK_SOCKAF(so, AF_INET6)) { 864 INP_WUNLOCK(inp); 865 error = ip6_ctloutput(so, sopt); 866 } else { 867 #endif 868 INP_WUNLOCK(inp); 869 error = ip_ctloutput(so, sopt); 870 #ifdef INET6 871 } 872 #endif 873 return (error); 874 } 875 876 switch (sopt->sopt_dir) { 877 case SOPT_SET: 878 switch (sopt->sopt_name) { 879 case UDP_ENCAP: 880 INP_WUNLOCK(inp); 881 error = sooptcopyin(sopt, &optval, sizeof optval, 882 sizeof optval); 883 if (error) 884 break; 885 inp = sotoinpcb(so); 886 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 887 INP_WLOCK(inp); 888 #ifdef IPSEC_NAT_T 889 up = intoudpcb(inp); 890 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 891 #endif 892 switch (optval) { 893 case 0: 894 /* Clear all UDP encap. */ 895 #ifdef IPSEC_NAT_T 896 up->u_flags &= ~UF_ESPINUDP_ALL; 897 #endif 898 break; 899 #ifdef IPSEC_NAT_T 900 case UDP_ENCAP_ESPINUDP: 901 case UDP_ENCAP_ESPINUDP_NON_IKE: 902 up->u_flags &= ~UF_ESPINUDP_ALL; 903 if (optval == UDP_ENCAP_ESPINUDP) 904 up->u_flags |= UF_ESPINUDP; 905 else if (optval == UDP_ENCAP_ESPINUDP_NON_IKE) 906 up->u_flags |= UF_ESPINUDP_NON_IKE; 907 break; 908 #endif 909 default: 910 error = EINVAL; 911 break; 912 } 913 INP_WUNLOCK(inp); 914 break; 915 default: 916 INP_WUNLOCK(inp); 917 error = ENOPROTOOPT; 918 break; 919 } 920 break; 921 case SOPT_GET: 922 switch (sopt->sopt_name) { 923 #ifdef IPSEC_NAT_T 924 case UDP_ENCAP: 925 up = intoudpcb(inp); 926 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 927 optval = up->u_flags & UF_ESPINUDP_ALL; 928 INP_WUNLOCK(inp); 929 error = sooptcopyout(sopt, &optval, sizeof optval); 930 break; 931 #endif 932 default: 933 INP_WUNLOCK(inp); 934 error = ENOPROTOOPT; 935 break; 936 } 937 break; 938 } 939 return (error); 940 } 941 942 static int 943 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr, 944 struct mbuf *control, struct thread *td) 945 { 946 struct udpiphdr *ui; 947 int len = m->m_pkthdr.len; 948 struct in_addr faddr, laddr; 949 struct cmsghdr *cm; 950 struct sockaddr_in *sin, src; 951 int error = 0; 952 int ipflags; 953 u_short fport, lport; 954 int unlock_udbinfo; 955 956 /* 957 * udp_output() may need to temporarily bind or connect the current 958 * inpcb. As such, we don't know up front whether we will need the 959 * pcbinfo lock or not. Do any work to decide what is needed up 960 * front before acquiring any locks. 961 */ 962 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 963 if (control) 964 m_freem(control); 965 m_freem(m); 966 return (EMSGSIZE); 967 } 968 969 src.sin_family = 0; 970 if (control != NULL) { 971 /* 972 * XXX: Currently, we assume all the optional information is 973 * stored in a single mbuf. 974 */ 975 if (control->m_next) { 976 m_freem(control); 977 m_freem(m); 978 return (EINVAL); 979 } 980 for (; control->m_len > 0; 981 control->m_data += CMSG_ALIGN(cm->cmsg_len), 982 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 983 cm = mtod(control, struct cmsghdr *); 984 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 985 || cm->cmsg_len > control->m_len) { 986 error = EINVAL; 987 break; 988 } 989 if (cm->cmsg_level != IPPROTO_IP) 990 continue; 991 992 switch (cm->cmsg_type) { 993 case IP_SENDSRCADDR: 994 if (cm->cmsg_len != 995 CMSG_LEN(sizeof(struct in_addr))) { 996 error = EINVAL; 997 break; 998 } 999 bzero(&src, sizeof(src)); 1000 src.sin_family = AF_INET; 1001 src.sin_len = sizeof(src); 1002 src.sin_port = inp->inp_lport; 1003 src.sin_addr = 1004 *(struct in_addr *)CMSG_DATA(cm); 1005 break; 1006 1007 default: 1008 error = ENOPROTOOPT; 1009 break; 1010 } 1011 if (error) 1012 break; 1013 } 1014 m_freem(control); 1015 } 1016 if (error) { 1017 m_freem(m); 1018 return (error); 1019 } 1020 1021 /* 1022 * Depending on whether or not the application has bound or connected 1023 * the socket, we may have to do varying levels of work. The optimal 1024 * case is for a connected UDP socket, as a global lock isn't 1025 * required at all. 1026 * 1027 * In order to decide which we need, we require stability of the 1028 * inpcb binding, which we ensure by acquiring a read lock on the 1029 * inpcb. This doesn't strictly follow the lock order, so we play 1030 * the trylock and retry game; note that we may end up with more 1031 * conservative locks than required the second time around, so later 1032 * assertions have to accept that. Further analysis of the number of 1033 * misses under contention is required. 1034 */ 1035 sin = (struct sockaddr_in *)addr; 1036 INP_RLOCK(inp); 1037 if (sin != NULL && 1038 (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) { 1039 INP_RUNLOCK(inp); 1040 INP_INFO_WLOCK(&V_udbinfo); 1041 INP_WLOCK(inp); 1042 unlock_udbinfo = 2; 1043 } else if ((sin != NULL && ( 1044 (sin->sin_addr.s_addr == INADDR_ANY) || 1045 (sin->sin_addr.s_addr == INADDR_BROADCAST) || 1046 (inp->inp_laddr.s_addr == INADDR_ANY) || 1047 (inp->inp_lport == 0))) || 1048 (src.sin_family == AF_INET)) { 1049 if (!INP_INFO_TRY_RLOCK(&V_udbinfo)) { 1050 INP_RUNLOCK(inp); 1051 INP_INFO_RLOCK(&V_udbinfo); 1052 INP_RLOCK(inp); 1053 } 1054 unlock_udbinfo = 1; 1055 } else 1056 unlock_udbinfo = 0; 1057 1058 /* 1059 * If the IP_SENDSRCADDR control message was specified, override the 1060 * source address for this datagram. Its use is invalidated if the 1061 * address thus specified is incomplete or clobbers other inpcbs. 1062 */ 1063 laddr = inp->inp_laddr; 1064 lport = inp->inp_lport; 1065 if (src.sin_family == AF_INET) { 1066 INP_INFO_LOCK_ASSERT(&V_udbinfo); 1067 if ((lport == 0) || 1068 (laddr.s_addr == INADDR_ANY && 1069 src.sin_addr.s_addr == INADDR_ANY)) { 1070 error = EINVAL; 1071 goto release; 1072 } 1073 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 1074 &laddr.s_addr, &lport, td->td_ucred); 1075 if (error) 1076 goto release; 1077 } 1078 1079 /* 1080 * If a UDP socket has been connected, then a local address/port will 1081 * have been selected and bound. 1082 * 1083 * If a UDP socket has not been connected to, then an explicit 1084 * destination address must be used, in which case a local 1085 * address/port may not have been selected and bound. 1086 */ 1087 if (sin != NULL) { 1088 INP_LOCK_ASSERT(inp); 1089 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1090 error = EISCONN; 1091 goto release; 1092 } 1093 1094 /* 1095 * Jail may rewrite the destination address, so let it do 1096 * that before we use it. 1097 */ 1098 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1099 if (error) 1100 goto release; 1101 1102 /* 1103 * If a local address or port hasn't yet been selected, or if 1104 * the destination address needs to be rewritten due to using 1105 * a special INADDR_ constant, invoke in_pcbconnect_setup() 1106 * to do the heavy lifting. Once a port is selected, we 1107 * commit the binding back to the socket; we also commit the 1108 * binding of the address if in jail. 1109 * 1110 * If we already have a valid binding and we're not 1111 * requesting a destination address rewrite, use a fast path. 1112 */ 1113 if (inp->inp_laddr.s_addr == INADDR_ANY || 1114 inp->inp_lport == 0 || 1115 sin->sin_addr.s_addr == INADDR_ANY || 1116 sin->sin_addr.s_addr == INADDR_BROADCAST) { 1117 INP_INFO_LOCK_ASSERT(&V_udbinfo); 1118 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, 1119 &lport, &faddr.s_addr, &fport, NULL, 1120 td->td_ucred); 1121 if (error) 1122 goto release; 1123 1124 /* 1125 * XXXRW: Why not commit the port if the address is 1126 * !INADDR_ANY? 1127 */ 1128 /* Commit the local port if newly assigned. */ 1129 if (inp->inp_laddr.s_addr == INADDR_ANY && 1130 inp->inp_lport == 0) { 1131 INP_INFO_WLOCK_ASSERT(&V_udbinfo); 1132 INP_WLOCK_ASSERT(inp); 1133 /* 1134 * Remember addr if jailed, to prevent 1135 * rebinding. 1136 */ 1137 if (prison_flag(td->td_ucred, PR_IP4)) 1138 inp->inp_laddr = laddr; 1139 inp->inp_lport = lport; 1140 if (in_pcbinshash(inp) != 0) { 1141 inp->inp_lport = 0; 1142 error = EAGAIN; 1143 goto release; 1144 } 1145 inp->inp_flags |= INP_ANONPORT; 1146 } 1147 } else { 1148 faddr = sin->sin_addr; 1149 fport = sin->sin_port; 1150 } 1151 } else { 1152 INP_LOCK_ASSERT(inp); 1153 faddr = inp->inp_faddr; 1154 fport = inp->inp_fport; 1155 if (faddr.s_addr == INADDR_ANY) { 1156 error = ENOTCONN; 1157 goto release; 1158 } 1159 } 1160 1161 /* 1162 * Calculate data length and get a mbuf for UDP, IP, and possible 1163 * link-layer headers. Immediate slide the data pointer back forward 1164 * since we won't use that space at this layer. 1165 */ 1166 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT); 1167 if (m == NULL) { 1168 error = ENOBUFS; 1169 goto release; 1170 } 1171 m->m_data += max_linkhdr; 1172 m->m_len -= max_linkhdr; 1173 m->m_pkthdr.len -= max_linkhdr; 1174 1175 /* 1176 * Fill in mbuf with extended UDP header and addresses and length put 1177 * into network format. 1178 */ 1179 ui = mtod(m, struct udpiphdr *); 1180 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 1181 ui->ui_pr = IPPROTO_UDP; 1182 ui->ui_src = laddr; 1183 ui->ui_dst = faddr; 1184 ui->ui_sport = lport; 1185 ui->ui_dport = fport; 1186 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 1187 1188 /* 1189 * Set the Don't Fragment bit in the IP header. 1190 */ 1191 if (inp->inp_flags & INP_DONTFRAG) { 1192 struct ip *ip; 1193 1194 ip = (struct ip *)&ui->ui_i; 1195 ip->ip_off |= IP_DF; 1196 } 1197 1198 ipflags = 0; 1199 if (inp->inp_socket->so_options & SO_DONTROUTE) 1200 ipflags |= IP_ROUTETOIF; 1201 if (inp->inp_socket->so_options & SO_BROADCAST) 1202 ipflags |= IP_ALLOWBROADCAST; 1203 if (inp->inp_flags & INP_ONESBCAST) 1204 ipflags |= IP_SENDONES; 1205 1206 #ifdef MAC 1207 mac_inpcb_create_mbuf(inp, m); 1208 #endif 1209 1210 /* 1211 * Set up checksum and output datagram. 1212 */ 1213 if (udp_cksum) { 1214 if (inp->inp_flags & INP_ONESBCAST) 1215 faddr.s_addr = INADDR_BROADCAST; 1216 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 1217 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 1218 m->m_pkthdr.csum_flags = CSUM_UDP; 1219 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 1220 } else 1221 ui->ui_sum = 0; 1222 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 1223 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 1224 ((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */ 1225 UDPSTAT_INC(udps_opackets); 1226 1227 if (unlock_udbinfo == 2) 1228 INP_INFO_WUNLOCK(&V_udbinfo); 1229 else if (unlock_udbinfo == 1) 1230 INP_INFO_RUNLOCK(&V_udbinfo); 1231 error = ip_output(m, inp->inp_options, NULL, ipflags, 1232 inp->inp_moptions, inp); 1233 if (unlock_udbinfo == 2) 1234 INP_WUNLOCK(inp); 1235 else 1236 INP_RUNLOCK(inp); 1237 return (error); 1238 1239 release: 1240 if (unlock_udbinfo == 2) { 1241 INP_WUNLOCK(inp); 1242 INP_INFO_WUNLOCK(&V_udbinfo); 1243 } else if (unlock_udbinfo == 1) { 1244 INP_RUNLOCK(inp); 1245 INP_INFO_RUNLOCK(&V_udbinfo); 1246 } else 1247 INP_RUNLOCK(inp); 1248 m_freem(m); 1249 return (error); 1250 } 1251 1252 1253 #if defined(IPSEC) && defined(IPSEC_NAT_T) 1254 #ifdef INET 1255 /* 1256 * Potentially decap ESP in UDP frame. Check for an ESP header 1257 * and optional marker; if present, strip the UDP header and 1258 * push the result through IPSec. 1259 * 1260 * Returns mbuf to be processed (potentially re-allocated) or 1261 * NULL if consumed and/or processed. 1262 */ 1263 static struct mbuf * 1264 udp4_espdecap(struct inpcb *inp, struct mbuf *m, int off) 1265 { 1266 size_t minlen, payload, skip, iphlen; 1267 caddr_t data; 1268 struct udpcb *up; 1269 struct m_tag *tag; 1270 struct udphdr *udphdr; 1271 struct ip *ip; 1272 1273 INP_RLOCK_ASSERT(inp); 1274 1275 /* 1276 * Pull up data so the longest case is contiguous: 1277 * IP/UDP hdr + non ESP marker + ESP hdr. 1278 */ 1279 minlen = off + sizeof(uint64_t) + sizeof(struct esp); 1280 if (minlen > m->m_pkthdr.len) 1281 minlen = m->m_pkthdr.len; 1282 if ((m = m_pullup(m, minlen)) == NULL) { 1283 V_ipsec4stat.in_inval++; 1284 return (NULL); /* Bypass caller processing. */ 1285 } 1286 data = mtod(m, caddr_t); /* Points to ip header. */ 1287 payload = m->m_len - off; /* Size of payload. */ 1288 1289 if (payload == 1 && data[off] == '\xff') 1290 return (m); /* NB: keepalive packet, no decap. */ 1291 1292 up = intoudpcb(inp); 1293 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 1294 KASSERT((up->u_flags & UF_ESPINUDP_ALL) != 0, 1295 ("u_flags 0x%x", up->u_flags)); 1296 1297 /* 1298 * Check that the payload is large enough to hold an 1299 * ESP header and compute the amount of data to remove. 1300 * 1301 * NB: the caller has already done a pullup for us. 1302 * XXX can we assume alignment and eliminate bcopys? 1303 */ 1304 if (up->u_flags & UF_ESPINUDP_NON_IKE) { 1305 /* 1306 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 1307 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, ignoring 1308 * possible AH mode non-IKE marker+non-ESP marker 1309 * from draft-ietf-ipsec-udp-encaps-00.txt. 1310 */ 1311 uint64_t marker; 1312 1313 if (payload <= sizeof(uint64_t) + sizeof(struct esp)) 1314 return (m); /* NB: no decap. */ 1315 bcopy(data + off, &marker, sizeof(uint64_t)); 1316 if (marker != 0) /* Non-IKE marker. */ 1317 return (m); /* NB: no decap. */ 1318 skip = sizeof(uint64_t) + sizeof(struct udphdr); 1319 } else { 1320 uint32_t spi; 1321 1322 if (payload <= sizeof(struct esp)) { 1323 V_ipsec4stat.in_inval++; 1324 m_freem(m); 1325 return (NULL); /* Discard. */ 1326 } 1327 bcopy(data + off, &spi, sizeof(uint32_t)); 1328 if (spi == 0) /* Non-ESP marker. */ 1329 return (m); /* NB: no decap. */ 1330 skip = sizeof(struct udphdr); 1331 } 1332 1333 /* 1334 * Setup a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember 1335 * the UDP ports. This is required if we want to select 1336 * the right SPD for multiple hosts behind same NAT. 1337 * 1338 * NB: ports are maintained in network byte order everywhere 1339 * in the NAT-T code. 1340 */ 1341 tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS, 1342 2 * sizeof(uint16_t), M_NOWAIT); 1343 if (tag == NULL) { 1344 V_ipsec4stat.in_nomem++; 1345 m_freem(m); 1346 return (NULL); /* Discard. */ 1347 } 1348 iphlen = off - sizeof(struct udphdr); 1349 udphdr = (struct udphdr *)(data + iphlen); 1350 ((uint16_t *)(tag + 1))[0] = udphdr->uh_sport; 1351 ((uint16_t *)(tag + 1))[1] = udphdr->uh_dport; 1352 m_tag_prepend(m, tag); 1353 1354 /* 1355 * Remove the UDP header (and possibly the non ESP marker) 1356 * IP header length is iphlen 1357 * Before: 1358 * <--- off ---> 1359 * +----+------+-----+ 1360 * | IP | UDP | ESP | 1361 * +----+------+-----+ 1362 * <-skip-> 1363 * After: 1364 * +----+-----+ 1365 * | IP | ESP | 1366 * +----+-----+ 1367 * <-skip-> 1368 */ 1369 ovbcopy(data, data + skip, iphlen); 1370 m_adj(m, skip); 1371 1372 ip = mtod(m, struct ip *); 1373 ip->ip_len -= skip; 1374 ip->ip_p = IPPROTO_ESP; 1375 1376 /* 1377 * We cannot yet update the cksums so clear any 1378 * h/w cksum flags as they are no longer valid. 1379 */ 1380 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) 1381 m->m_pkthdr.csum_flags &= ~(CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 1382 1383 (void) ipsec4_common_input(m, iphlen, ip->ip_p); 1384 return (NULL); /* NB: consumed, bypass processing. */ 1385 } 1386 #endif /* INET */ 1387 #endif /* defined(IPSEC) && defined(IPSEC_NAT_T) */ 1388 1389 static void 1390 udp_abort(struct socket *so) 1391 { 1392 struct inpcb *inp; 1393 1394 inp = sotoinpcb(so); 1395 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 1396 INP_INFO_WLOCK(&V_udbinfo); 1397 INP_WLOCK(inp); 1398 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1399 in_pcbdisconnect(inp); 1400 inp->inp_laddr.s_addr = INADDR_ANY; 1401 soisdisconnected(so); 1402 } 1403 INP_WUNLOCK(inp); 1404 INP_INFO_WUNLOCK(&V_udbinfo); 1405 } 1406 1407 static int 1408 udp_attach(struct socket *so, int proto, struct thread *td) 1409 { 1410 struct inpcb *inp; 1411 int error; 1412 1413 inp = sotoinpcb(so); 1414 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 1415 error = soreserve(so, udp_sendspace, udp_recvspace); 1416 if (error) 1417 return (error); 1418 INP_INFO_WLOCK(&V_udbinfo); 1419 error = in_pcballoc(so, &V_udbinfo); 1420 if (error) { 1421 INP_INFO_WUNLOCK(&V_udbinfo); 1422 return (error); 1423 } 1424 1425 inp = sotoinpcb(so); 1426 inp->inp_vflag |= INP_IPV4; 1427 inp->inp_ip_ttl = V_ip_defttl; 1428 1429 error = udp_newudpcb(inp); 1430 if (error) { 1431 in_pcbdetach(inp); 1432 in_pcbfree(inp); 1433 INP_INFO_WUNLOCK(&V_udbinfo); 1434 return (error); 1435 } 1436 1437 INP_WUNLOCK(inp); 1438 INP_INFO_WUNLOCK(&V_udbinfo); 1439 return (0); 1440 } 1441 1442 int 1443 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f) 1444 { 1445 struct inpcb *inp; 1446 struct udpcb *up; 1447 1448 KASSERT(so->so_type == SOCK_DGRAM, 1449 ("udp_set_kernel_tunneling: !dgram")); 1450 inp = sotoinpcb(so); 1451 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL")); 1452 INP_WLOCK(inp); 1453 up = intoudpcb(inp); 1454 if (up->u_tun_func != NULL) { 1455 INP_WUNLOCK(inp); 1456 return (EBUSY); 1457 } 1458 up->u_tun_func = f; 1459 INP_WUNLOCK(inp); 1460 return (0); 1461 } 1462 1463 static int 1464 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1465 { 1466 struct inpcb *inp; 1467 int error; 1468 1469 inp = sotoinpcb(so); 1470 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1471 INP_INFO_WLOCK(&V_udbinfo); 1472 INP_WLOCK(inp); 1473 error = in_pcbbind(inp, nam, td->td_ucred); 1474 INP_WUNLOCK(inp); 1475 INP_INFO_WUNLOCK(&V_udbinfo); 1476 return (error); 1477 } 1478 1479 static void 1480 udp_close(struct socket *so) 1481 { 1482 struct inpcb *inp; 1483 1484 inp = sotoinpcb(so); 1485 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1486 INP_INFO_WLOCK(&V_udbinfo); 1487 INP_WLOCK(inp); 1488 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1489 in_pcbdisconnect(inp); 1490 inp->inp_laddr.s_addr = INADDR_ANY; 1491 soisdisconnected(so); 1492 } 1493 INP_WUNLOCK(inp); 1494 INP_INFO_WUNLOCK(&V_udbinfo); 1495 } 1496 1497 static int 1498 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1499 { 1500 struct inpcb *inp; 1501 int error; 1502 struct sockaddr_in *sin; 1503 1504 inp = sotoinpcb(so); 1505 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1506 INP_INFO_WLOCK(&V_udbinfo); 1507 INP_WLOCK(inp); 1508 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1509 INP_WUNLOCK(inp); 1510 INP_INFO_WUNLOCK(&V_udbinfo); 1511 return (EISCONN); 1512 } 1513 sin = (struct sockaddr_in *)nam; 1514 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1515 if (error != 0) { 1516 INP_WUNLOCK(inp); 1517 INP_INFO_WUNLOCK(&V_udbinfo); 1518 return (error); 1519 } 1520 error = in_pcbconnect(inp, nam, td->td_ucred); 1521 if (error == 0) 1522 soisconnected(so); 1523 INP_WUNLOCK(inp); 1524 INP_INFO_WUNLOCK(&V_udbinfo); 1525 return (error); 1526 } 1527 1528 static void 1529 udp_detach(struct socket *so) 1530 { 1531 struct inpcb *inp; 1532 struct udpcb *up; 1533 1534 inp = sotoinpcb(so); 1535 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1536 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY, 1537 ("udp_detach: not disconnected")); 1538 INP_INFO_WLOCK(&V_udbinfo); 1539 INP_WLOCK(inp); 1540 up = intoudpcb(inp); 1541 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 1542 inp->inp_ppcb = NULL; 1543 in_pcbdetach(inp); 1544 in_pcbfree(inp); 1545 INP_INFO_WUNLOCK(&V_udbinfo); 1546 udp_discardcb(up); 1547 } 1548 1549 static int 1550 udp_disconnect(struct socket *so) 1551 { 1552 struct inpcb *inp; 1553 1554 inp = sotoinpcb(so); 1555 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1556 INP_INFO_WLOCK(&V_udbinfo); 1557 INP_WLOCK(inp); 1558 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1559 INP_WUNLOCK(inp); 1560 INP_INFO_WUNLOCK(&V_udbinfo); 1561 return (ENOTCONN); 1562 } 1563 1564 in_pcbdisconnect(inp); 1565 inp->inp_laddr.s_addr = INADDR_ANY; 1566 SOCK_LOCK(so); 1567 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1568 SOCK_UNLOCK(so); 1569 INP_WUNLOCK(inp); 1570 INP_INFO_WUNLOCK(&V_udbinfo); 1571 return (0); 1572 } 1573 1574 static int 1575 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1576 struct mbuf *control, struct thread *td) 1577 { 1578 struct inpcb *inp; 1579 1580 inp = sotoinpcb(so); 1581 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1582 return (udp_output(inp, m, addr, control, td)); 1583 } 1584 1585 int 1586 udp_shutdown(struct socket *so) 1587 { 1588 struct inpcb *inp; 1589 1590 inp = sotoinpcb(so); 1591 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1592 INP_WLOCK(inp); 1593 socantsendmore(so); 1594 INP_WUNLOCK(inp); 1595 return (0); 1596 } 1597 1598 struct pr_usrreqs udp_usrreqs = { 1599 .pru_abort = udp_abort, 1600 .pru_attach = udp_attach, 1601 .pru_bind = udp_bind, 1602 .pru_connect = udp_connect, 1603 .pru_control = in_control, 1604 .pru_detach = udp_detach, 1605 .pru_disconnect = udp_disconnect, 1606 .pru_peeraddr = in_getpeeraddr, 1607 .pru_send = udp_send, 1608 .pru_soreceive = soreceive_dgram, 1609 .pru_sosend = sosend_dgram, 1610 .pru_shutdown = udp_shutdown, 1611 .pru_sockaddr = in_getsockaddr, 1612 .pru_sosetlabel = in_pcbsosetlabel, 1613 .pru_close = udp_close, 1614 }; 1615