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 * Copyright (c) 2010-2011 Juniper Networks, Inc. 6 * All rights reserved. 7 * 8 * Portions of this software were developed by Robert N. M. Watson under 9 * contract to Juniper Networks, Inc. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95 36 */ 37 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include "opt_ipfw.h" 42 #include "opt_inet.h" 43 #include "opt_inet6.h" 44 #include "opt_ipsec.h" 45 46 #include <sys/param.h> 47 #include <sys/domain.h> 48 #include <sys/eventhandler.h> 49 #include <sys/jail.h> 50 #include <sys/kernel.h> 51 #include <sys/lock.h> 52 #include <sys/malloc.h> 53 #include <sys/mbuf.h> 54 #include <sys/priv.h> 55 #include <sys/proc.h> 56 #include <sys/protosw.h> 57 #include <sys/signalvar.h> 58 #include <sys/socket.h> 59 #include <sys/socketvar.h> 60 #include <sys/sx.h> 61 #include <sys/sysctl.h> 62 #include <sys/syslog.h> 63 #include <sys/systm.h> 64 65 #include <vm/uma.h> 66 67 #include <net/if.h> 68 #include <net/route.h> 69 70 #include <netinet/in.h> 71 #include <netinet/in_pcb.h> 72 #include <netinet/in_systm.h> 73 #include <netinet/in_var.h> 74 #include <netinet/ip.h> 75 #ifdef INET6 76 #include <netinet/ip6.h> 77 #endif 78 #include <netinet/ip_icmp.h> 79 #include <netinet/icmp_var.h> 80 #include <netinet/ip_var.h> 81 #include <netinet/ip_options.h> 82 #ifdef INET6 83 #include <netinet6/ip6_var.h> 84 #endif 85 #include <netinet/udp.h> 86 #include <netinet/udp_var.h> 87 88 #ifdef IPSEC 89 #include <netipsec/ipsec.h> 90 #include <netipsec/esp.h> 91 #endif 92 93 #include <machine/in_cksum.h> 94 95 #include <security/mac/mac_framework.h> 96 97 /* 98 * UDP protocol implementation. 99 * Per RFC 768, August, 1980. 100 */ 101 102 /* 103 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums 104 * removes the only data integrity mechanism for packets and malformed 105 * packets that would otherwise be discarded due to bad checksums, and may 106 * cause problems (especially for NFS data blocks). 107 */ 108 VNET_DEFINE(int, udp_cksum) = 1; 109 SYSCTL_VNET_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, 110 &VNET_NAME(udp_cksum), 0, "compute udp checksum"); 111 112 int udp_log_in_vain = 0; 113 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW, 114 &udp_log_in_vain, 0, "Log all incoming UDP packets"); 115 116 VNET_DEFINE(int, udp_blackhole) = 0; 117 SYSCTL_VNET_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW, 118 &VNET_NAME(udp_blackhole), 0, 119 "Do not send port unreachables for refused connects"); 120 121 u_long udp_sendspace = 9216; /* really max datagram size */ 122 /* 40 1K datagrams */ 123 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 124 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 125 126 u_long udp_recvspace = 40 * (1024 + 127 #ifdef INET6 128 sizeof(struct sockaddr_in6) 129 #else 130 sizeof(struct sockaddr_in) 131 #endif 132 ); 133 134 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 135 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 136 137 VNET_DEFINE(struct inpcbhead, udb); /* from udp_var.h */ 138 VNET_DEFINE(struct inpcbinfo, udbinfo); 139 static VNET_DEFINE(uma_zone_t, udpcb_zone); 140 #define V_udpcb_zone VNET(udpcb_zone) 141 142 #ifndef UDBHASHSIZE 143 #define UDBHASHSIZE 128 144 #endif 145 146 VNET_DEFINE(struct udpstat, udpstat); /* from udp_var.h */ 147 SYSCTL_VNET_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW, 148 &VNET_NAME(udpstat), udpstat, 149 "UDP statistics (struct udpstat, netinet/udp_var.h)"); 150 151 #ifdef INET 152 static void udp_detach(struct socket *so); 153 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 154 struct mbuf *, struct thread *); 155 #endif 156 157 #ifdef IPSEC 158 #ifdef IPSEC_NAT_T 159 #define UF_ESPINUDP_ALL (UF_ESPINUDP_NON_IKE|UF_ESPINUDP) 160 #ifdef INET 161 static struct mbuf *udp4_espdecap(struct inpcb *, struct mbuf *, int); 162 #endif 163 #endif /* IPSEC_NAT_T */ 164 #endif /* IPSEC */ 165 166 static void 167 udp_zone_change(void *tag) 168 { 169 170 uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets); 171 uma_zone_set_max(V_udpcb_zone, maxsockets); 172 } 173 174 static int 175 udp_inpcb_init(void *mem, int size, int flags) 176 { 177 struct inpcb *inp; 178 179 inp = mem; 180 INP_LOCK_INIT(inp, "inp", "udpinp"); 181 return (0); 182 } 183 184 void 185 udp_init(void) 186 { 187 188 in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE, 189 "udp_inpcb", udp_inpcb_init, NULL, UMA_ZONE_NOFREE, 190 IPI_HASHFIELDS_2TUPLE); 191 V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb), 192 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 193 uma_zone_set_max(V_udpcb_zone, maxsockets); 194 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL, 195 EVENTHANDLER_PRI_ANY); 196 } 197 198 /* 199 * Kernel module interface for updating udpstat. The argument is an index 200 * into udpstat treated as an array of u_long. While this encodes the 201 * general layout of udpstat into the caller, it doesn't encode its location, 202 * so that future changes to add, for example, per-CPU stats support won't 203 * cause binary compatibility problems for kernel modules. 204 */ 205 void 206 kmod_udpstat_inc(int statnum) 207 { 208 209 (*((u_long *)&V_udpstat + statnum))++; 210 } 211 212 int 213 udp_newudpcb(struct inpcb *inp) 214 { 215 struct udpcb *up; 216 217 up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO); 218 if (up == NULL) 219 return (ENOBUFS); 220 inp->inp_ppcb = up; 221 return (0); 222 } 223 224 void 225 udp_discardcb(struct udpcb *up) 226 { 227 228 uma_zfree(V_udpcb_zone, up); 229 } 230 231 #ifdef VIMAGE 232 void 233 udp_destroy(void) 234 { 235 236 in_pcbinfo_destroy(&V_udbinfo); 237 uma_zdestroy(V_udpcb_zone); 238 } 239 #endif 240 241 #ifdef INET 242 /* 243 * Subroutine of udp_input(), which appends the provided mbuf chain to the 244 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 245 * contains the source address. If the socket ends up being an IPv6 socket, 246 * udp_append() will convert to a sockaddr_in6 before passing the address 247 * into the socket code. 248 */ 249 static void 250 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off, 251 struct sockaddr_in *udp_in) 252 { 253 struct sockaddr *append_sa; 254 struct socket *so; 255 struct mbuf *opts = 0; 256 #ifdef INET6 257 struct sockaddr_in6 udp_in6; 258 #endif 259 struct udpcb *up; 260 261 INP_LOCK_ASSERT(inp); 262 263 /* 264 * Engage the tunneling protocol. 265 */ 266 up = intoudpcb(inp); 267 if (up->u_tun_func != NULL) { 268 (*up->u_tun_func)(n, off, inp); 269 return; 270 } 271 272 if (n == NULL) 273 return; 274 275 off += sizeof(struct udphdr); 276 277 #ifdef IPSEC 278 /* Check AH/ESP integrity. */ 279 if (ipsec4_in_reject(n, inp)) { 280 m_freem(n); 281 V_ipsec4stat.in_polvio++; 282 return; 283 } 284 #ifdef IPSEC_NAT_T 285 up = intoudpcb(inp); 286 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 287 if (up->u_flags & UF_ESPINUDP_ALL) { /* IPSec UDP encaps. */ 288 n = udp4_espdecap(inp, n, off); 289 if (n == NULL) /* Consumed. */ 290 return; 291 } 292 #endif /* IPSEC_NAT_T */ 293 #endif /* IPSEC */ 294 #ifdef MAC 295 if (mac_inpcb_check_deliver(inp, n) != 0) { 296 m_freem(n); 297 return; 298 } 299 #endif /* MAC */ 300 if (inp->inp_flags & INP_CONTROLOPTS || 301 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 302 #ifdef INET6 303 if (inp->inp_vflag & INP_IPV6) 304 (void)ip6_savecontrol_v4(inp, n, &opts, NULL); 305 else 306 #endif /* INET6 */ 307 ip_savecontrol(inp, &opts, ip, n); 308 } 309 #ifdef INET6 310 if (inp->inp_vflag & INP_IPV6) { 311 bzero(&udp_in6, sizeof(udp_in6)); 312 udp_in6.sin6_len = sizeof(udp_in6); 313 udp_in6.sin6_family = AF_INET6; 314 in6_sin_2_v4mapsin6(udp_in, &udp_in6); 315 append_sa = (struct sockaddr *)&udp_in6; 316 } else 317 #endif /* INET6 */ 318 append_sa = (struct sockaddr *)udp_in; 319 m_adj(n, off); 320 321 so = inp->inp_socket; 322 SOCKBUF_LOCK(&so->so_rcv); 323 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 324 SOCKBUF_UNLOCK(&so->so_rcv); 325 m_freem(n); 326 if (opts) 327 m_freem(opts); 328 UDPSTAT_INC(udps_fullsock); 329 } else 330 sorwakeup_locked(so); 331 } 332 333 void 334 udp_input(struct mbuf *m, int off) 335 { 336 int iphlen = off; 337 struct ip *ip; 338 struct udphdr *uh; 339 struct ifnet *ifp; 340 struct inpcb *inp; 341 uint16_t len, ip_len; 342 struct ip save_ip; 343 struct sockaddr_in udp_in; 344 struct m_tag *fwd_tag; 345 346 ifp = m->m_pkthdr.rcvif; 347 UDPSTAT_INC(udps_ipackets); 348 349 /* 350 * Strip IP options, if any; should skip this, make available to 351 * user, and use on returned packets, but we don't yet have a way to 352 * check the checksum with options still present. 353 */ 354 if (iphlen > sizeof (struct ip)) { 355 ip_stripoptions(m); 356 iphlen = sizeof(struct ip); 357 } 358 359 /* 360 * Get IP and UDP header together in first mbuf. 361 */ 362 ip = mtod(m, struct ip *); 363 if (m->m_len < iphlen + sizeof(struct udphdr)) { 364 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 365 UDPSTAT_INC(udps_hdrops); 366 return; 367 } 368 ip = mtod(m, struct ip *); 369 } 370 uh = (struct udphdr *)((caddr_t)ip + iphlen); 371 372 /* 373 * Destination port of 0 is illegal, based on RFC768. 374 */ 375 if (uh->uh_dport == 0) 376 goto badunlocked; 377 378 /* 379 * Construct sockaddr format source address. Stuff source address 380 * and datagram in user buffer. 381 */ 382 bzero(&udp_in, sizeof(udp_in)); 383 udp_in.sin_len = sizeof(udp_in); 384 udp_in.sin_family = AF_INET; 385 udp_in.sin_port = uh->uh_sport; 386 udp_in.sin_addr = ip->ip_src; 387 388 /* 389 * Make mbuf data length reflect UDP length. If not enough data to 390 * reflect UDP length, drop. 391 */ 392 len = ntohs((u_short)uh->uh_ulen); 393 ip_len = ntohs(ip->ip_len) - iphlen; 394 if (ip_len != len) { 395 if (len > ip_len || len < sizeof(struct udphdr)) { 396 UDPSTAT_INC(udps_badlen); 397 goto badunlocked; 398 } 399 m_adj(m, len - ip_len); 400 } 401 402 /* 403 * Save a copy of the IP header in case we want restore it for 404 * sending an ICMP error message in response. 405 */ 406 if (!V_udp_blackhole) 407 save_ip = *ip; 408 else 409 memset(&save_ip, 0, sizeof(save_ip)); 410 411 /* 412 * Checksum extended UDP header and data. 413 */ 414 if (uh->uh_sum) { 415 u_short uh_sum; 416 417 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 418 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 419 uh_sum = m->m_pkthdr.csum_data; 420 else 421 uh_sum = in_pseudo(ip->ip_src.s_addr, 422 ip->ip_dst.s_addr, htonl((u_short)len + 423 m->m_pkthdr.csum_data + IPPROTO_UDP)); 424 uh_sum ^= 0xffff; 425 } else { 426 char b[9]; 427 428 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 429 bzero(((struct ipovly *)ip)->ih_x1, 9); 430 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 431 uh_sum = in_cksum(m, len + sizeof (struct ip)); 432 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 433 } 434 if (uh_sum) { 435 UDPSTAT_INC(udps_badsum); 436 m_freem(m); 437 return; 438 } 439 } else 440 UDPSTAT_INC(udps_nosum); 441 442 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 443 in_broadcast(ip->ip_dst, ifp)) { 444 struct inpcb *last; 445 struct ip_moptions *imo; 446 447 INP_INFO_RLOCK(&V_udbinfo); 448 last = NULL; 449 LIST_FOREACH(inp, &V_udb, inp_list) { 450 if (inp->inp_lport != uh->uh_dport) 451 continue; 452 #ifdef INET6 453 if ((inp->inp_vflag & INP_IPV4) == 0) 454 continue; 455 #endif 456 if (inp->inp_laddr.s_addr != INADDR_ANY && 457 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 458 continue; 459 if (inp->inp_faddr.s_addr != INADDR_ANY && 460 inp->inp_faddr.s_addr != ip->ip_src.s_addr) 461 continue; 462 if (inp->inp_fport != 0 && 463 inp->inp_fport != uh->uh_sport) 464 continue; 465 466 INP_RLOCK(inp); 467 468 /* 469 * XXXRW: Because we weren't holding either the inpcb 470 * or the hash lock when we checked for a match 471 * before, we should probably recheck now that the 472 * inpcb lock is held. 473 */ 474 475 /* 476 * Handle socket delivery policy for any-source 477 * and source-specific multicast. [RFC3678] 478 */ 479 imo = inp->inp_moptions; 480 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 481 struct sockaddr_in group; 482 int blocked; 483 if (imo == NULL) { 484 INP_RUNLOCK(inp); 485 continue; 486 } 487 bzero(&group, sizeof(struct sockaddr_in)); 488 group.sin_len = sizeof(struct sockaddr_in); 489 group.sin_family = AF_INET; 490 group.sin_addr = ip->ip_dst; 491 492 blocked = imo_multi_filter(imo, ifp, 493 (struct sockaddr *)&group, 494 (struct sockaddr *)&udp_in); 495 if (blocked != MCAST_PASS) { 496 if (blocked == MCAST_NOTGMEMBER) 497 IPSTAT_INC(ips_notmember); 498 if (blocked == MCAST_NOTSMEMBER || 499 blocked == MCAST_MUTED) 500 UDPSTAT_INC(udps_filtermcast); 501 INP_RUNLOCK(inp); 502 continue; 503 } 504 } 505 if (last != NULL) { 506 struct mbuf *n; 507 508 n = m_copy(m, 0, M_COPYALL); 509 udp_append(last, ip, n, iphlen, &udp_in); 510 INP_RUNLOCK(last); 511 } 512 last = inp; 513 /* 514 * Don't look for additional matches if this one does 515 * not have either the SO_REUSEPORT or SO_REUSEADDR 516 * socket options set. This heuristic avoids 517 * searching through all pcbs in the common case of a 518 * non-shared port. It assumes that an application 519 * will never clear these options after setting them. 520 */ 521 if ((last->inp_socket->so_options & 522 (SO_REUSEPORT|SO_REUSEADDR)) == 0) 523 break; 524 } 525 526 if (last == NULL) { 527 /* 528 * No matching pcb found; discard datagram. (No need 529 * to send an ICMP Port Unreachable for a broadcast 530 * or multicast datgram.) 531 */ 532 UDPSTAT_INC(udps_noportbcast); 533 if (inp) 534 INP_RUNLOCK(inp); 535 INP_INFO_RUNLOCK(&V_udbinfo); 536 goto badunlocked; 537 } 538 udp_append(last, ip, m, iphlen, &udp_in); 539 INP_RUNLOCK(last); 540 INP_INFO_RUNLOCK(&V_udbinfo); 541 return; 542 } 543 544 /* 545 * Locate pcb for datagram. 546 */ 547 548 /* 549 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. 550 */ 551 if ((m->m_flags & M_IP_NEXTHOP) && 552 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) { 553 struct sockaddr_in *next_hop; 554 555 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 556 557 /* 558 * Transparently forwarded. Pretend to be the destination. 559 * Already got one like this? 560 */ 561 inp = in_pcblookup_mbuf(&V_udbinfo, ip->ip_src, uh->uh_sport, 562 ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m); 563 if (!inp) { 564 /* 565 * It's new. Try to find the ambushing socket. 566 * Because we've rewritten the destination address, 567 * any hardware-generated hash is ignored. 568 */ 569 inp = in_pcblookup(&V_udbinfo, ip->ip_src, 570 uh->uh_sport, next_hop->sin_addr, 571 next_hop->sin_port ? htons(next_hop->sin_port) : 572 uh->uh_dport, INPLOOKUP_WILDCARD | 573 INPLOOKUP_RLOCKPCB, ifp); 574 } 575 /* Remove the tag from the packet. We don't need it anymore. */ 576 m_tag_delete(m, fwd_tag); 577 m->m_flags &= ~M_IP_NEXTHOP; 578 } else 579 inp = in_pcblookup_mbuf(&V_udbinfo, ip->ip_src, uh->uh_sport, 580 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD | 581 INPLOOKUP_RLOCKPCB, ifp, m); 582 if (inp == NULL) { 583 if (udp_log_in_vain) { 584 char buf[4*sizeof "123"]; 585 586 strcpy(buf, inet_ntoa(ip->ip_dst)); 587 log(LOG_INFO, 588 "Connection attempt to UDP %s:%d from %s:%d\n", 589 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 590 ntohs(uh->uh_sport)); 591 } 592 UDPSTAT_INC(udps_noport); 593 if (m->m_flags & (M_BCAST | M_MCAST)) { 594 UDPSTAT_INC(udps_noportbcast); 595 goto badunlocked; 596 } 597 if (V_udp_blackhole) 598 goto badunlocked; 599 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 600 goto badunlocked; 601 *ip = save_ip; 602 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 603 return; 604 } 605 606 /* 607 * Check the minimum TTL for socket. 608 */ 609 INP_RLOCK_ASSERT(inp); 610 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) { 611 INP_RUNLOCK(inp); 612 m_freem(m); 613 return; 614 } 615 udp_append(inp, ip, m, iphlen, &udp_in); 616 INP_RUNLOCK(inp); 617 return; 618 619 badunlocked: 620 m_freem(m); 621 } 622 #endif /* INET */ 623 624 /* 625 * Notify a udp user of an asynchronous error; just wake up so that they can 626 * collect error status. 627 */ 628 struct inpcb * 629 udp_notify(struct inpcb *inp, int errno) 630 { 631 632 /* 633 * While udp_ctlinput() always calls udp_notify() with a read lock 634 * when invoking it directly, in_pcbnotifyall() currently uses write 635 * locks due to sharing code with TCP. For now, accept either a read 636 * or a write lock, but a read lock is sufficient. 637 */ 638 INP_LOCK_ASSERT(inp); 639 640 inp->inp_socket->so_error = errno; 641 sorwakeup(inp->inp_socket); 642 sowwakeup(inp->inp_socket); 643 return (inp); 644 } 645 646 #ifdef INET 647 void 648 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 649 { 650 struct ip *ip = vip; 651 struct udphdr *uh; 652 struct in_addr faddr; 653 struct inpcb *inp; 654 655 faddr = ((struct sockaddr_in *)sa)->sin_addr; 656 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 657 return; 658 659 /* 660 * Redirects don't need to be handled up here. 661 */ 662 if (PRC_IS_REDIRECT(cmd)) 663 return; 664 665 /* 666 * Hostdead is ugly because it goes linearly through all PCBs. 667 * 668 * XXX: We never get this from ICMP, otherwise it makes an excellent 669 * DoS attack on machines with many connections. 670 */ 671 if (cmd == PRC_HOSTDEAD) 672 ip = NULL; 673 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 674 return; 675 if (ip != NULL) { 676 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 677 inp = in_pcblookup(&V_udbinfo, faddr, uh->uh_dport, 678 ip->ip_src, uh->uh_sport, INPLOOKUP_RLOCKPCB, NULL); 679 if (inp != NULL) { 680 INP_RLOCK_ASSERT(inp); 681 if (inp->inp_socket != NULL) { 682 udp_notify(inp, inetctlerrmap[cmd]); 683 } 684 INP_RUNLOCK(inp); 685 } 686 } else 687 in_pcbnotifyall(&V_udbinfo, faddr, inetctlerrmap[cmd], 688 udp_notify); 689 } 690 #endif /* INET */ 691 692 static int 693 udp_pcblist(SYSCTL_HANDLER_ARGS) 694 { 695 int error, i, n; 696 struct inpcb *inp, **inp_list; 697 inp_gen_t gencnt; 698 struct xinpgen xig; 699 700 /* 701 * The process of preparing the PCB list is too time-consuming and 702 * resource-intensive to repeat twice on every request. 703 */ 704 if (req->oldptr == 0) { 705 n = V_udbinfo.ipi_count; 706 n += imax(n / 8, 10); 707 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb); 708 return (0); 709 } 710 711 if (req->newptr != 0) 712 return (EPERM); 713 714 /* 715 * OK, now we're committed to doing something. 716 */ 717 INP_INFO_RLOCK(&V_udbinfo); 718 gencnt = V_udbinfo.ipi_gencnt; 719 n = V_udbinfo.ipi_count; 720 INP_INFO_RUNLOCK(&V_udbinfo); 721 722 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 723 + n * sizeof(struct xinpcb)); 724 if (error != 0) 725 return (error); 726 727 xig.xig_len = sizeof xig; 728 xig.xig_count = n; 729 xig.xig_gen = gencnt; 730 xig.xig_sogen = so_gencnt; 731 error = SYSCTL_OUT(req, &xig, sizeof xig); 732 if (error) 733 return (error); 734 735 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 736 if (inp_list == 0) 737 return (ENOMEM); 738 739 INP_INFO_RLOCK(&V_udbinfo); 740 for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n; 741 inp = LIST_NEXT(inp, inp_list)) { 742 INP_WLOCK(inp); 743 if (inp->inp_gencnt <= gencnt && 744 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 745 in_pcbref(inp); 746 inp_list[i++] = inp; 747 } 748 INP_WUNLOCK(inp); 749 } 750 INP_INFO_RUNLOCK(&V_udbinfo); 751 n = i; 752 753 error = 0; 754 for (i = 0; i < n; i++) { 755 inp = inp_list[i]; 756 INP_RLOCK(inp); 757 if (inp->inp_gencnt <= gencnt) { 758 struct xinpcb xi; 759 760 bzero(&xi, sizeof(xi)); 761 xi.xi_len = sizeof xi; 762 /* XXX should avoid extra copy */ 763 bcopy(inp, &xi.xi_inp, sizeof *inp); 764 if (inp->inp_socket) 765 sotoxsocket(inp->inp_socket, &xi.xi_socket); 766 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 767 INP_RUNLOCK(inp); 768 error = SYSCTL_OUT(req, &xi, sizeof xi); 769 } else 770 INP_RUNLOCK(inp); 771 } 772 INP_INFO_WLOCK(&V_udbinfo); 773 for (i = 0; i < n; i++) { 774 inp = inp_list[i]; 775 INP_RLOCK(inp); 776 if (!in_pcbrele_rlocked(inp)) 777 INP_RUNLOCK(inp); 778 } 779 INP_INFO_WUNLOCK(&V_udbinfo); 780 781 if (!error) { 782 /* 783 * Give the user an updated idea of our state. If the 784 * generation differs from what we told her before, she knows 785 * that something happened while we were processing this 786 * request, and it might be necessary to retry. 787 */ 788 INP_INFO_RLOCK(&V_udbinfo); 789 xig.xig_gen = V_udbinfo.ipi_gencnt; 790 xig.xig_sogen = so_gencnt; 791 xig.xig_count = V_udbinfo.ipi_count; 792 INP_INFO_RUNLOCK(&V_udbinfo); 793 error = SYSCTL_OUT(req, &xig, sizeof xig); 794 } 795 free(inp_list, M_TEMP); 796 return (error); 797 } 798 799 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, 800 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0, 801 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 802 803 #ifdef INET 804 static int 805 udp_getcred(SYSCTL_HANDLER_ARGS) 806 { 807 struct xucred xuc; 808 struct sockaddr_in addrs[2]; 809 struct inpcb *inp; 810 int error; 811 812 error = priv_check(req->td, PRIV_NETINET_GETCRED); 813 if (error) 814 return (error); 815 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 816 if (error) 817 return (error); 818 inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 819 addrs[0].sin_addr, addrs[0].sin_port, 820 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL); 821 if (inp != NULL) { 822 INP_RLOCK_ASSERT(inp); 823 if (inp->inp_socket == NULL) 824 error = ENOENT; 825 if (error == 0) 826 error = cr_canseeinpcb(req->td->td_ucred, inp); 827 if (error == 0) 828 cru2x(inp->inp_cred, &xuc); 829 INP_RUNLOCK(inp); 830 } else 831 error = ENOENT; 832 if (error == 0) 833 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 834 return (error); 835 } 836 837 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 838 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 839 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 840 #endif /* INET */ 841 842 int 843 udp_ctloutput(struct socket *so, struct sockopt *sopt) 844 { 845 int error = 0, optval; 846 struct inpcb *inp; 847 #ifdef IPSEC_NAT_T 848 struct udpcb *up; 849 #endif 850 851 inp = sotoinpcb(so); 852 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 853 INP_WLOCK(inp); 854 if (sopt->sopt_level != IPPROTO_UDP) { 855 #ifdef INET6 856 if (INP_CHECK_SOCKAF(so, AF_INET6)) { 857 INP_WUNLOCK(inp); 858 error = ip6_ctloutput(so, sopt); 859 } 860 #endif 861 #if defined(INET) && defined(INET6) 862 else 863 #endif 864 #ifdef INET 865 { 866 INP_WUNLOCK(inp); 867 error = ip_ctloutput(so, sopt); 868 } 869 #endif 870 return (error); 871 } 872 873 switch (sopt->sopt_dir) { 874 case SOPT_SET: 875 switch (sopt->sopt_name) { 876 case UDP_ENCAP: 877 INP_WUNLOCK(inp); 878 error = sooptcopyin(sopt, &optval, sizeof optval, 879 sizeof optval); 880 if (error) 881 break; 882 inp = sotoinpcb(so); 883 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 884 INP_WLOCK(inp); 885 #ifdef IPSEC_NAT_T 886 up = intoudpcb(inp); 887 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 888 #endif 889 switch (optval) { 890 case 0: 891 /* Clear all UDP encap. */ 892 #ifdef IPSEC_NAT_T 893 up->u_flags &= ~UF_ESPINUDP_ALL; 894 #endif 895 break; 896 #ifdef IPSEC_NAT_T 897 case UDP_ENCAP_ESPINUDP: 898 case UDP_ENCAP_ESPINUDP_NON_IKE: 899 up->u_flags &= ~UF_ESPINUDP_ALL; 900 if (optval == UDP_ENCAP_ESPINUDP) 901 up->u_flags |= UF_ESPINUDP; 902 else if (optval == UDP_ENCAP_ESPINUDP_NON_IKE) 903 up->u_flags |= UF_ESPINUDP_NON_IKE; 904 break; 905 #endif 906 default: 907 error = EINVAL; 908 break; 909 } 910 INP_WUNLOCK(inp); 911 break; 912 default: 913 INP_WUNLOCK(inp); 914 error = ENOPROTOOPT; 915 break; 916 } 917 break; 918 case SOPT_GET: 919 switch (sopt->sopt_name) { 920 #ifdef IPSEC_NAT_T 921 case UDP_ENCAP: 922 up = intoudpcb(inp); 923 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 924 optval = up->u_flags & UF_ESPINUDP_ALL; 925 INP_WUNLOCK(inp); 926 error = sooptcopyout(sopt, &optval, sizeof optval); 927 break; 928 #endif 929 default: 930 INP_WUNLOCK(inp); 931 error = ENOPROTOOPT; 932 break; 933 } 934 break; 935 } 936 return (error); 937 } 938 939 #ifdef INET 940 #define UH_WLOCKED 2 941 #define UH_RLOCKED 1 942 #define UH_UNLOCKED 0 943 static int 944 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr, 945 struct mbuf *control, struct thread *td) 946 { 947 struct udpiphdr *ui; 948 int len = m->m_pkthdr.len; 949 struct in_addr faddr, laddr; 950 struct cmsghdr *cm; 951 struct sockaddr_in *sin, src; 952 int error = 0; 953 int ipflags; 954 u_short fport, lport; 955 int unlock_udbinfo; 956 u_char tos; 957 958 /* 959 * udp_output() may need to temporarily bind or connect the current 960 * inpcb. As such, we don't know up front whether we will need the 961 * pcbinfo lock or not. Do any work to decide what is needed up 962 * front before acquiring any locks. 963 */ 964 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 965 if (control) 966 m_freem(control); 967 m_freem(m); 968 return (EMSGSIZE); 969 } 970 971 src.sin_family = 0; 972 INP_RLOCK(inp); 973 tos = inp->inp_ip_tos; 974 if (control != NULL) { 975 /* 976 * XXX: Currently, we assume all the optional information is 977 * stored in a single mbuf. 978 */ 979 if (control->m_next) { 980 INP_RUNLOCK(inp); 981 m_freem(control); 982 m_freem(m); 983 return (EINVAL); 984 } 985 for (; control->m_len > 0; 986 control->m_data += CMSG_ALIGN(cm->cmsg_len), 987 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 988 cm = mtod(control, struct cmsghdr *); 989 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 990 || cm->cmsg_len > control->m_len) { 991 error = EINVAL; 992 break; 993 } 994 if (cm->cmsg_level != IPPROTO_IP) 995 continue; 996 997 switch (cm->cmsg_type) { 998 case IP_SENDSRCADDR: 999 if (cm->cmsg_len != 1000 CMSG_LEN(sizeof(struct in_addr))) { 1001 error = EINVAL; 1002 break; 1003 } 1004 bzero(&src, sizeof(src)); 1005 src.sin_family = AF_INET; 1006 src.sin_len = sizeof(src); 1007 src.sin_port = inp->inp_lport; 1008 src.sin_addr = 1009 *(struct in_addr *)CMSG_DATA(cm); 1010 break; 1011 1012 case IP_TOS: 1013 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) { 1014 error = EINVAL; 1015 break; 1016 } 1017 tos = *(u_char *)CMSG_DATA(cm); 1018 break; 1019 1020 default: 1021 error = ENOPROTOOPT; 1022 break; 1023 } 1024 if (error) 1025 break; 1026 } 1027 m_freem(control); 1028 } 1029 if (error) { 1030 INP_RUNLOCK(inp); 1031 m_freem(m); 1032 return (error); 1033 } 1034 1035 /* 1036 * Depending on whether or not the application has bound or connected 1037 * the socket, we may have to do varying levels of work. The optimal 1038 * case is for a connected UDP socket, as a global lock isn't 1039 * required at all. 1040 * 1041 * In order to decide which we need, we require stability of the 1042 * inpcb binding, which we ensure by acquiring a read lock on the 1043 * inpcb. This doesn't strictly follow the lock order, so we play 1044 * the trylock and retry game; note that we may end up with more 1045 * conservative locks than required the second time around, so later 1046 * assertions have to accept that. Further analysis of the number of 1047 * misses under contention is required. 1048 * 1049 * XXXRW: Check that hash locking update here is correct. 1050 */ 1051 sin = (struct sockaddr_in *)addr; 1052 if (sin != NULL && 1053 (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) { 1054 INP_RUNLOCK(inp); 1055 INP_WLOCK(inp); 1056 INP_HASH_WLOCK(&V_udbinfo); 1057 unlock_udbinfo = UH_WLOCKED; 1058 } else if ((sin != NULL && ( 1059 (sin->sin_addr.s_addr == INADDR_ANY) || 1060 (sin->sin_addr.s_addr == INADDR_BROADCAST) || 1061 (inp->inp_laddr.s_addr == INADDR_ANY) || 1062 (inp->inp_lport == 0))) || 1063 (src.sin_family == AF_INET)) { 1064 INP_HASH_RLOCK(&V_udbinfo); 1065 unlock_udbinfo = UH_RLOCKED; 1066 } else 1067 unlock_udbinfo = UH_UNLOCKED; 1068 1069 /* 1070 * If the IP_SENDSRCADDR control message was specified, override the 1071 * source address for this datagram. Its use is invalidated if the 1072 * address thus specified is incomplete or clobbers other inpcbs. 1073 */ 1074 laddr = inp->inp_laddr; 1075 lport = inp->inp_lport; 1076 if (src.sin_family == AF_INET) { 1077 INP_HASH_LOCK_ASSERT(&V_udbinfo); 1078 if ((lport == 0) || 1079 (laddr.s_addr == INADDR_ANY && 1080 src.sin_addr.s_addr == INADDR_ANY)) { 1081 error = EINVAL; 1082 goto release; 1083 } 1084 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 1085 &laddr.s_addr, &lport, td->td_ucred); 1086 if (error) 1087 goto release; 1088 } 1089 1090 /* 1091 * If a UDP socket has been connected, then a local address/port will 1092 * have been selected and bound. 1093 * 1094 * If a UDP socket has not been connected to, then an explicit 1095 * destination address must be used, in which case a local 1096 * address/port may not have been selected and bound. 1097 */ 1098 if (sin != NULL) { 1099 INP_LOCK_ASSERT(inp); 1100 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1101 error = EISCONN; 1102 goto release; 1103 } 1104 1105 /* 1106 * Jail may rewrite the destination address, so let it do 1107 * that before we use it. 1108 */ 1109 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1110 if (error) 1111 goto release; 1112 1113 /* 1114 * If a local address or port hasn't yet been selected, or if 1115 * the destination address needs to be rewritten due to using 1116 * a special INADDR_ constant, invoke in_pcbconnect_setup() 1117 * to do the heavy lifting. Once a port is selected, we 1118 * commit the binding back to the socket; we also commit the 1119 * binding of the address if in jail. 1120 * 1121 * If we already have a valid binding and we're not 1122 * requesting a destination address rewrite, use a fast path. 1123 */ 1124 if (inp->inp_laddr.s_addr == INADDR_ANY || 1125 inp->inp_lport == 0 || 1126 sin->sin_addr.s_addr == INADDR_ANY || 1127 sin->sin_addr.s_addr == INADDR_BROADCAST) { 1128 INP_HASH_LOCK_ASSERT(&V_udbinfo); 1129 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, 1130 &lport, &faddr.s_addr, &fport, NULL, 1131 td->td_ucred); 1132 if (error) 1133 goto release; 1134 1135 /* 1136 * XXXRW: Why not commit the port if the address is 1137 * !INADDR_ANY? 1138 */ 1139 /* Commit the local port if newly assigned. */ 1140 if (inp->inp_laddr.s_addr == INADDR_ANY && 1141 inp->inp_lport == 0) { 1142 INP_WLOCK_ASSERT(inp); 1143 INP_HASH_WLOCK_ASSERT(&V_udbinfo); 1144 /* 1145 * Remember addr if jailed, to prevent 1146 * rebinding. 1147 */ 1148 if (prison_flag(td->td_ucred, PR_IP4)) 1149 inp->inp_laddr = laddr; 1150 inp->inp_lport = lport; 1151 if (in_pcbinshash(inp) != 0) { 1152 inp->inp_lport = 0; 1153 error = EAGAIN; 1154 goto release; 1155 } 1156 inp->inp_flags |= INP_ANONPORT; 1157 } 1158 } else { 1159 faddr = sin->sin_addr; 1160 fport = sin->sin_port; 1161 } 1162 } else { 1163 INP_LOCK_ASSERT(inp); 1164 faddr = inp->inp_faddr; 1165 fport = inp->inp_fport; 1166 if (faddr.s_addr == INADDR_ANY) { 1167 error = ENOTCONN; 1168 goto release; 1169 } 1170 } 1171 1172 /* 1173 * Calculate data length and get a mbuf for UDP, IP, and possible 1174 * link-layer headers. Immediate slide the data pointer back forward 1175 * since we won't use that space at this layer. 1176 */ 1177 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT); 1178 if (m == NULL) { 1179 error = ENOBUFS; 1180 goto release; 1181 } 1182 m->m_data += max_linkhdr; 1183 m->m_len -= max_linkhdr; 1184 m->m_pkthdr.len -= max_linkhdr; 1185 1186 /* 1187 * Fill in mbuf with extended UDP header and addresses and length put 1188 * into network format. 1189 */ 1190 ui = mtod(m, struct udpiphdr *); 1191 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 1192 ui->ui_pr = IPPROTO_UDP; 1193 ui->ui_src = laddr; 1194 ui->ui_dst = faddr; 1195 ui->ui_sport = lport; 1196 ui->ui_dport = fport; 1197 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 1198 1199 /* 1200 * Set the Don't Fragment bit in the IP header. 1201 */ 1202 if (inp->inp_flags & INP_DONTFRAG) { 1203 struct ip *ip; 1204 1205 ip = (struct ip *)&ui->ui_i; 1206 ip->ip_off |= htons(IP_DF); 1207 } 1208 1209 ipflags = 0; 1210 if (inp->inp_socket->so_options & SO_DONTROUTE) 1211 ipflags |= IP_ROUTETOIF; 1212 if (inp->inp_socket->so_options & SO_BROADCAST) 1213 ipflags |= IP_ALLOWBROADCAST; 1214 if (inp->inp_flags & INP_ONESBCAST) 1215 ipflags |= IP_SENDONES; 1216 1217 #ifdef MAC 1218 mac_inpcb_create_mbuf(inp, m); 1219 #endif 1220 1221 /* 1222 * Set up checksum and output datagram. 1223 */ 1224 if (V_udp_cksum) { 1225 if (inp->inp_flags & INP_ONESBCAST) 1226 faddr.s_addr = INADDR_BROADCAST; 1227 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 1228 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 1229 m->m_pkthdr.csum_flags = CSUM_UDP; 1230 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 1231 } else 1232 ui->ui_sum = 0; 1233 ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len); 1234 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 1235 ((struct ip *)ui)->ip_tos = tos; /* XXX */ 1236 UDPSTAT_INC(udps_opackets); 1237 1238 if (unlock_udbinfo == UH_WLOCKED) 1239 INP_HASH_WUNLOCK(&V_udbinfo); 1240 else if (unlock_udbinfo == UH_RLOCKED) 1241 INP_HASH_RUNLOCK(&V_udbinfo); 1242 error = ip_output(m, inp->inp_options, NULL, ipflags, 1243 inp->inp_moptions, inp); 1244 if (unlock_udbinfo == UH_WLOCKED) 1245 INP_WUNLOCK(inp); 1246 else 1247 INP_RUNLOCK(inp); 1248 return (error); 1249 1250 release: 1251 if (unlock_udbinfo == UH_WLOCKED) { 1252 INP_HASH_WUNLOCK(&V_udbinfo); 1253 INP_WUNLOCK(inp); 1254 } else if (unlock_udbinfo == UH_RLOCKED) { 1255 INP_HASH_RUNLOCK(&V_udbinfo); 1256 INP_RUNLOCK(inp); 1257 } else 1258 INP_RUNLOCK(inp); 1259 m_freem(m); 1260 return (error); 1261 } 1262 1263 1264 #if defined(IPSEC) && defined(IPSEC_NAT_T) 1265 /* 1266 * Potentially decap ESP in UDP frame. Check for an ESP header 1267 * and optional marker; if present, strip the UDP header and 1268 * push the result through IPSec. 1269 * 1270 * Returns mbuf to be processed (potentially re-allocated) or 1271 * NULL if consumed and/or processed. 1272 */ 1273 static struct mbuf * 1274 udp4_espdecap(struct inpcb *inp, struct mbuf *m, int off) 1275 { 1276 size_t minlen, payload, skip, iphlen; 1277 caddr_t data; 1278 struct udpcb *up; 1279 struct m_tag *tag; 1280 struct udphdr *udphdr; 1281 struct ip *ip; 1282 1283 INP_RLOCK_ASSERT(inp); 1284 1285 /* 1286 * Pull up data so the longest case is contiguous: 1287 * IP/UDP hdr + non ESP marker + ESP hdr. 1288 */ 1289 minlen = off + sizeof(uint64_t) + sizeof(struct esp); 1290 if (minlen > m->m_pkthdr.len) 1291 minlen = m->m_pkthdr.len; 1292 if ((m = m_pullup(m, minlen)) == NULL) { 1293 V_ipsec4stat.in_inval++; 1294 return (NULL); /* Bypass caller processing. */ 1295 } 1296 data = mtod(m, caddr_t); /* Points to ip header. */ 1297 payload = m->m_len - off; /* Size of payload. */ 1298 1299 if (payload == 1 && data[off] == '\xff') 1300 return (m); /* NB: keepalive packet, no decap. */ 1301 1302 up = intoudpcb(inp); 1303 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 1304 KASSERT((up->u_flags & UF_ESPINUDP_ALL) != 0, 1305 ("u_flags 0x%x", up->u_flags)); 1306 1307 /* 1308 * Check that the payload is large enough to hold an 1309 * ESP header and compute the amount of data to remove. 1310 * 1311 * NB: the caller has already done a pullup for us. 1312 * XXX can we assume alignment and eliminate bcopys? 1313 */ 1314 if (up->u_flags & UF_ESPINUDP_NON_IKE) { 1315 /* 1316 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 1317 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, ignoring 1318 * possible AH mode non-IKE marker+non-ESP marker 1319 * from draft-ietf-ipsec-udp-encaps-00.txt. 1320 */ 1321 uint64_t marker; 1322 1323 if (payload <= sizeof(uint64_t) + sizeof(struct esp)) 1324 return (m); /* NB: no decap. */ 1325 bcopy(data + off, &marker, sizeof(uint64_t)); 1326 if (marker != 0) /* Non-IKE marker. */ 1327 return (m); /* NB: no decap. */ 1328 skip = sizeof(uint64_t) + sizeof(struct udphdr); 1329 } else { 1330 uint32_t spi; 1331 1332 if (payload <= sizeof(struct esp)) { 1333 V_ipsec4stat.in_inval++; 1334 m_freem(m); 1335 return (NULL); /* Discard. */ 1336 } 1337 bcopy(data + off, &spi, sizeof(uint32_t)); 1338 if (spi == 0) /* Non-ESP marker. */ 1339 return (m); /* NB: no decap. */ 1340 skip = sizeof(struct udphdr); 1341 } 1342 1343 /* 1344 * Setup a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember 1345 * the UDP ports. This is required if we want to select 1346 * the right SPD for multiple hosts behind same NAT. 1347 * 1348 * NB: ports are maintained in network byte order everywhere 1349 * in the NAT-T code. 1350 */ 1351 tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS, 1352 2 * sizeof(uint16_t), M_NOWAIT); 1353 if (tag == NULL) { 1354 V_ipsec4stat.in_nomem++; 1355 m_freem(m); 1356 return (NULL); /* Discard. */ 1357 } 1358 iphlen = off - sizeof(struct udphdr); 1359 udphdr = (struct udphdr *)(data + iphlen); 1360 ((uint16_t *)(tag + 1))[0] = udphdr->uh_sport; 1361 ((uint16_t *)(tag + 1))[1] = udphdr->uh_dport; 1362 m_tag_prepend(m, tag); 1363 1364 /* 1365 * Remove the UDP header (and possibly the non ESP marker) 1366 * IP header length is iphlen 1367 * Before: 1368 * <--- off ---> 1369 * +----+------+-----+ 1370 * | IP | UDP | ESP | 1371 * +----+------+-----+ 1372 * <-skip-> 1373 * After: 1374 * +----+-----+ 1375 * | IP | ESP | 1376 * +----+-----+ 1377 * <-skip-> 1378 */ 1379 ovbcopy(data, data + skip, iphlen); 1380 m_adj(m, skip); 1381 1382 ip = mtod(m, struct ip *); 1383 ip->ip_len = htons(ntohs(ip->ip_len) - skip); 1384 ip->ip_p = IPPROTO_ESP; 1385 1386 /* 1387 * We cannot yet update the cksums so clear any 1388 * h/w cksum flags as they are no longer valid. 1389 */ 1390 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) 1391 m->m_pkthdr.csum_flags &= ~(CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 1392 1393 (void) ipsec4_common_input(m, iphlen, ip->ip_p); 1394 return (NULL); /* NB: consumed, bypass processing. */ 1395 } 1396 #endif /* defined(IPSEC) && defined(IPSEC_NAT_T) */ 1397 1398 static void 1399 udp_abort(struct socket *so) 1400 { 1401 struct inpcb *inp; 1402 1403 inp = sotoinpcb(so); 1404 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 1405 INP_WLOCK(inp); 1406 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1407 INP_HASH_WLOCK(&V_udbinfo); 1408 in_pcbdisconnect(inp); 1409 inp->inp_laddr.s_addr = INADDR_ANY; 1410 INP_HASH_WUNLOCK(&V_udbinfo); 1411 soisdisconnected(so); 1412 } 1413 INP_WUNLOCK(inp); 1414 } 1415 1416 static int 1417 udp_attach(struct socket *so, int proto, struct thread *td) 1418 { 1419 struct inpcb *inp; 1420 int error; 1421 1422 inp = sotoinpcb(so); 1423 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 1424 error = soreserve(so, udp_sendspace, udp_recvspace); 1425 if (error) 1426 return (error); 1427 INP_INFO_WLOCK(&V_udbinfo); 1428 error = in_pcballoc(so, &V_udbinfo); 1429 if (error) { 1430 INP_INFO_WUNLOCK(&V_udbinfo); 1431 return (error); 1432 } 1433 1434 inp = sotoinpcb(so); 1435 inp->inp_vflag |= INP_IPV4; 1436 inp->inp_ip_ttl = V_ip_defttl; 1437 1438 error = udp_newudpcb(inp); 1439 if (error) { 1440 in_pcbdetach(inp); 1441 in_pcbfree(inp); 1442 INP_INFO_WUNLOCK(&V_udbinfo); 1443 return (error); 1444 } 1445 1446 INP_WUNLOCK(inp); 1447 INP_INFO_WUNLOCK(&V_udbinfo); 1448 return (0); 1449 } 1450 #endif /* INET */ 1451 1452 int 1453 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f) 1454 { 1455 struct inpcb *inp; 1456 struct udpcb *up; 1457 1458 KASSERT(so->so_type == SOCK_DGRAM, 1459 ("udp_set_kernel_tunneling: !dgram")); 1460 inp = sotoinpcb(so); 1461 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL")); 1462 INP_WLOCK(inp); 1463 up = intoudpcb(inp); 1464 if (up->u_tun_func != NULL) { 1465 INP_WUNLOCK(inp); 1466 return (EBUSY); 1467 } 1468 up->u_tun_func = f; 1469 INP_WUNLOCK(inp); 1470 return (0); 1471 } 1472 1473 #ifdef INET 1474 static int 1475 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1476 { 1477 struct inpcb *inp; 1478 int error; 1479 1480 inp = sotoinpcb(so); 1481 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1482 INP_WLOCK(inp); 1483 INP_HASH_WLOCK(&V_udbinfo); 1484 error = in_pcbbind(inp, nam, td->td_ucred); 1485 INP_HASH_WUNLOCK(&V_udbinfo); 1486 INP_WUNLOCK(inp); 1487 return (error); 1488 } 1489 1490 static void 1491 udp_close(struct socket *so) 1492 { 1493 struct inpcb *inp; 1494 1495 inp = sotoinpcb(so); 1496 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1497 INP_WLOCK(inp); 1498 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1499 INP_HASH_WLOCK(&V_udbinfo); 1500 in_pcbdisconnect(inp); 1501 inp->inp_laddr.s_addr = INADDR_ANY; 1502 INP_HASH_WUNLOCK(&V_udbinfo); 1503 soisdisconnected(so); 1504 } 1505 INP_WUNLOCK(inp); 1506 } 1507 1508 static int 1509 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1510 { 1511 struct inpcb *inp; 1512 int error; 1513 struct sockaddr_in *sin; 1514 1515 inp = sotoinpcb(so); 1516 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1517 INP_WLOCK(inp); 1518 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1519 INP_WUNLOCK(inp); 1520 return (EISCONN); 1521 } 1522 sin = (struct sockaddr_in *)nam; 1523 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1524 if (error != 0) { 1525 INP_WUNLOCK(inp); 1526 return (error); 1527 } 1528 INP_HASH_WLOCK(&V_udbinfo); 1529 error = in_pcbconnect(inp, nam, td->td_ucred); 1530 INP_HASH_WUNLOCK(&V_udbinfo); 1531 if (error == 0) 1532 soisconnected(so); 1533 INP_WUNLOCK(inp); 1534 return (error); 1535 } 1536 1537 static void 1538 udp_detach(struct socket *so) 1539 { 1540 struct inpcb *inp; 1541 struct udpcb *up; 1542 1543 inp = sotoinpcb(so); 1544 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1545 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY, 1546 ("udp_detach: not disconnected")); 1547 INP_INFO_WLOCK(&V_udbinfo); 1548 INP_WLOCK(inp); 1549 up = intoudpcb(inp); 1550 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 1551 inp->inp_ppcb = NULL; 1552 in_pcbdetach(inp); 1553 in_pcbfree(inp); 1554 INP_INFO_WUNLOCK(&V_udbinfo); 1555 udp_discardcb(up); 1556 } 1557 1558 static int 1559 udp_disconnect(struct socket *so) 1560 { 1561 struct inpcb *inp; 1562 1563 inp = sotoinpcb(so); 1564 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1565 INP_WLOCK(inp); 1566 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1567 INP_WUNLOCK(inp); 1568 return (ENOTCONN); 1569 } 1570 INP_HASH_WLOCK(&V_udbinfo); 1571 in_pcbdisconnect(inp); 1572 inp->inp_laddr.s_addr = INADDR_ANY; 1573 INP_HASH_WUNLOCK(&V_udbinfo); 1574 SOCK_LOCK(so); 1575 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1576 SOCK_UNLOCK(so); 1577 INP_WUNLOCK(inp); 1578 return (0); 1579 } 1580 1581 static int 1582 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1583 struct mbuf *control, struct thread *td) 1584 { 1585 struct inpcb *inp; 1586 1587 inp = sotoinpcb(so); 1588 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1589 return (udp_output(inp, m, addr, control, td)); 1590 } 1591 #endif /* INET */ 1592 1593 int 1594 udp_shutdown(struct socket *so) 1595 { 1596 struct inpcb *inp; 1597 1598 inp = sotoinpcb(so); 1599 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1600 INP_WLOCK(inp); 1601 socantsendmore(so); 1602 INP_WUNLOCK(inp); 1603 return (0); 1604 } 1605 1606 #ifdef INET 1607 struct pr_usrreqs udp_usrreqs = { 1608 .pru_abort = udp_abort, 1609 .pru_attach = udp_attach, 1610 .pru_bind = udp_bind, 1611 .pru_connect = udp_connect, 1612 .pru_control = in_control, 1613 .pru_detach = udp_detach, 1614 .pru_disconnect = udp_disconnect, 1615 .pru_peeraddr = in_getpeeraddr, 1616 .pru_send = udp_send, 1617 .pru_soreceive = soreceive_dgram, 1618 .pru_sosend = sosend_dgram, 1619 .pru_shutdown = udp_shutdown, 1620 .pru_sockaddr = in_getsockaddr, 1621 .pru_sosetlabel = in_pcbsosetlabel, 1622 .pru_close = udp_close, 1623 }; 1624 #endif /* INET */ 1625