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_PCPUSTAT_DEFINE(struct udpstat, udpstat); /* from udp_var.h */ 147 VNET_PCPUSTAT_SYSINIT(udpstat); 148 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat, 149 udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)"); 150 151 #ifdef VIMAGE 152 VNET_PCPUSTAT_SYSUNINIT(udpstat); 153 #endif /* VIMAGE */ 154 #ifdef INET 155 static void udp_detach(struct socket *so); 156 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 157 struct mbuf *, struct thread *); 158 #endif 159 160 #ifdef IPSEC 161 #ifdef IPSEC_NAT_T 162 #define UF_ESPINUDP_ALL (UF_ESPINUDP_NON_IKE|UF_ESPINUDP) 163 #ifdef INET 164 static struct mbuf *udp4_espdecap(struct inpcb *, struct mbuf *, int); 165 #endif 166 #endif /* IPSEC_NAT_T */ 167 #endif /* IPSEC */ 168 169 static void 170 udp_zone_change(void *tag) 171 { 172 173 uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets); 174 uma_zone_set_max(V_udpcb_zone, maxsockets); 175 } 176 177 static int 178 udp_inpcb_init(void *mem, int size, int flags) 179 { 180 struct inpcb *inp; 181 182 inp = mem; 183 INP_LOCK_INIT(inp, "inp", "udpinp"); 184 return (0); 185 } 186 187 void 188 udp_init(void) 189 { 190 191 in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE, 192 "udp_inpcb", udp_inpcb_init, NULL, UMA_ZONE_NOFREE, 193 IPI_HASHFIELDS_2TUPLE); 194 V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb), 195 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 196 uma_zone_set_max(V_udpcb_zone, maxsockets); 197 uma_zone_set_warning(V_udpcb_zone, "kern.ipc.maxsockets limit reached"); 198 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL, 199 EVENTHANDLER_PRI_ANY); 200 } 201 202 /* 203 * Kernel module interface for updating udpstat. The argument is an index 204 * into udpstat treated as an array of u_long. While this encodes the 205 * general layout of udpstat into the caller, it doesn't encode its location, 206 * so that future changes to add, for example, per-CPU stats support won't 207 * cause binary compatibility problems for kernel modules. 208 */ 209 void 210 kmod_udpstat_inc(int statnum) 211 { 212 213 counter_u64_add(VNET(udpstat)[statnum], 1); 214 } 215 216 int 217 udp_newudpcb(struct inpcb *inp) 218 { 219 struct udpcb *up; 220 221 up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO); 222 if (up == NULL) 223 return (ENOBUFS); 224 inp->inp_ppcb = up; 225 return (0); 226 } 227 228 void 229 udp_discardcb(struct udpcb *up) 230 { 231 232 uma_zfree(V_udpcb_zone, up); 233 } 234 235 #ifdef VIMAGE 236 void 237 udp_destroy(void) 238 { 239 240 in_pcbinfo_destroy(&V_udbinfo); 241 uma_zdestroy(V_udpcb_zone); 242 } 243 #endif 244 245 #ifdef INET 246 /* 247 * Subroutine of udp_input(), which appends the provided mbuf chain to the 248 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 249 * contains the source address. If the socket ends up being an IPv6 socket, 250 * udp_append() will convert to a sockaddr_in6 before passing the address 251 * into the socket code. 252 */ 253 static void 254 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off, 255 struct sockaddr_in *udp_in) 256 { 257 struct sockaddr *append_sa; 258 struct socket *so; 259 struct mbuf *opts = 0; 260 #ifdef INET6 261 struct sockaddr_in6 udp_in6; 262 #endif 263 struct udpcb *up; 264 265 INP_LOCK_ASSERT(inp); 266 267 /* 268 * Engage the tunneling protocol. 269 */ 270 up = intoudpcb(inp); 271 if (up->u_tun_func != NULL) { 272 (*up->u_tun_func)(n, off, inp); 273 return; 274 } 275 276 if (n == NULL) 277 return; 278 279 off += sizeof(struct udphdr); 280 281 #ifdef IPSEC 282 /* Check AH/ESP integrity. */ 283 if (ipsec4_in_reject(n, inp)) { 284 m_freem(n); 285 IPSECSTAT_INC(ips_in_polvio); 286 return; 287 } 288 #ifdef IPSEC_NAT_T 289 up = intoudpcb(inp); 290 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 291 if (up->u_flags & UF_ESPINUDP_ALL) { /* IPSec UDP encaps. */ 292 n = udp4_espdecap(inp, n, off); 293 if (n == NULL) /* Consumed. */ 294 return; 295 } 296 #endif /* IPSEC_NAT_T */ 297 #endif /* IPSEC */ 298 #ifdef MAC 299 if (mac_inpcb_check_deliver(inp, n) != 0) { 300 m_freem(n); 301 return; 302 } 303 #endif /* MAC */ 304 if (inp->inp_flags & INP_CONTROLOPTS || 305 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 306 #ifdef INET6 307 if (inp->inp_vflag & INP_IPV6) 308 (void)ip6_savecontrol_v4(inp, n, &opts, NULL); 309 else 310 #endif /* INET6 */ 311 ip_savecontrol(inp, &opts, ip, n); 312 } 313 #ifdef INET6 314 if (inp->inp_vflag & INP_IPV6) { 315 bzero(&udp_in6, sizeof(udp_in6)); 316 udp_in6.sin6_len = sizeof(udp_in6); 317 udp_in6.sin6_family = AF_INET6; 318 in6_sin_2_v4mapsin6(udp_in, &udp_in6); 319 append_sa = (struct sockaddr *)&udp_in6; 320 } else 321 #endif /* INET6 */ 322 append_sa = (struct sockaddr *)udp_in; 323 m_adj(n, off); 324 325 so = inp->inp_socket; 326 SOCKBUF_LOCK(&so->so_rcv); 327 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 328 SOCKBUF_UNLOCK(&so->so_rcv); 329 m_freem(n); 330 if (opts) 331 m_freem(opts); 332 UDPSTAT_INC(udps_fullsock); 333 } else 334 sorwakeup_locked(so); 335 } 336 337 void 338 udp_input(struct mbuf *m, int off) 339 { 340 int iphlen = off; 341 struct ip *ip; 342 struct udphdr *uh; 343 struct ifnet *ifp; 344 struct inpcb *inp; 345 uint16_t len, ip_len; 346 struct ip save_ip; 347 struct sockaddr_in udp_in; 348 struct m_tag *fwd_tag; 349 350 ifp = m->m_pkthdr.rcvif; 351 UDPSTAT_INC(udps_ipackets); 352 353 /* 354 * Strip IP options, if any; should skip this, make available to 355 * user, and use on returned packets, but we don't yet have a way to 356 * check the checksum with options still present. 357 */ 358 if (iphlen > sizeof (struct ip)) { 359 ip_stripoptions(m); 360 iphlen = sizeof(struct ip); 361 } 362 363 /* 364 * Get IP and UDP header together in first mbuf. 365 */ 366 ip = mtod(m, struct ip *); 367 if (m->m_len < iphlen + sizeof(struct udphdr)) { 368 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 369 UDPSTAT_INC(udps_hdrops); 370 return; 371 } 372 ip = mtod(m, struct ip *); 373 } 374 uh = (struct udphdr *)((caddr_t)ip + iphlen); 375 376 /* 377 * Destination port of 0 is illegal, based on RFC768. 378 */ 379 if (uh->uh_dport == 0) 380 goto badunlocked; 381 382 /* 383 * Construct sockaddr format source address. Stuff source address 384 * and datagram in user buffer. 385 */ 386 bzero(&udp_in, sizeof(udp_in)); 387 udp_in.sin_len = sizeof(udp_in); 388 udp_in.sin_family = AF_INET; 389 udp_in.sin_port = uh->uh_sport; 390 udp_in.sin_addr = ip->ip_src; 391 392 /* 393 * Make mbuf data length reflect UDP length. If not enough data to 394 * reflect UDP length, drop. 395 */ 396 len = ntohs((u_short)uh->uh_ulen); 397 ip_len = ntohs(ip->ip_len) - iphlen; 398 if (ip_len != len) { 399 if (len > ip_len || len < sizeof(struct udphdr)) { 400 UDPSTAT_INC(udps_badlen); 401 goto badunlocked; 402 } 403 m_adj(m, len - ip_len); 404 } 405 406 /* 407 * Save a copy of the IP header in case we want restore it for 408 * sending an ICMP error message in response. 409 */ 410 if (!V_udp_blackhole) 411 save_ip = *ip; 412 else 413 memset(&save_ip, 0, sizeof(save_ip)); 414 415 /* 416 * Checksum extended UDP header and data. 417 */ 418 if (uh->uh_sum) { 419 u_short uh_sum; 420 421 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 422 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 423 uh_sum = m->m_pkthdr.csum_data; 424 else 425 uh_sum = in_pseudo(ip->ip_src.s_addr, 426 ip->ip_dst.s_addr, htonl((u_short)len + 427 m->m_pkthdr.csum_data + IPPROTO_UDP)); 428 uh_sum ^= 0xffff; 429 } else { 430 char b[9]; 431 432 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 433 bzero(((struct ipovly *)ip)->ih_x1, 9); 434 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 435 uh_sum = in_cksum(m, len + sizeof (struct ip)); 436 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 437 } 438 if (uh_sum) { 439 UDPSTAT_INC(udps_badsum); 440 m_freem(m); 441 return; 442 } 443 } else 444 UDPSTAT_INC(udps_nosum); 445 446 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 447 in_broadcast(ip->ip_dst, ifp)) { 448 struct inpcb *last; 449 struct ip_moptions *imo; 450 451 INP_INFO_RLOCK(&V_udbinfo); 452 last = NULL; 453 LIST_FOREACH(inp, &V_udb, inp_list) { 454 if (inp->inp_lport != uh->uh_dport) 455 continue; 456 #ifdef INET6 457 if ((inp->inp_vflag & INP_IPV4) == 0) 458 continue; 459 #endif 460 if (inp->inp_laddr.s_addr != INADDR_ANY && 461 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 462 continue; 463 if (inp->inp_faddr.s_addr != INADDR_ANY && 464 inp->inp_faddr.s_addr != ip->ip_src.s_addr) 465 continue; 466 if (inp->inp_fport != 0 && 467 inp->inp_fport != uh->uh_sport) 468 continue; 469 470 INP_RLOCK(inp); 471 472 /* 473 * XXXRW: Because we weren't holding either the inpcb 474 * or the hash lock when we checked for a match 475 * before, we should probably recheck now that the 476 * inpcb lock is held. 477 */ 478 479 /* 480 * Handle socket delivery policy for any-source 481 * and source-specific multicast. [RFC3678] 482 */ 483 imo = inp->inp_moptions; 484 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 485 struct sockaddr_in group; 486 int blocked; 487 if (imo == NULL) { 488 INP_RUNLOCK(inp); 489 continue; 490 } 491 bzero(&group, sizeof(struct sockaddr_in)); 492 group.sin_len = sizeof(struct sockaddr_in); 493 group.sin_family = AF_INET; 494 group.sin_addr = ip->ip_dst; 495 496 blocked = imo_multi_filter(imo, ifp, 497 (struct sockaddr *)&group, 498 (struct sockaddr *)&udp_in); 499 if (blocked != MCAST_PASS) { 500 if (blocked == MCAST_NOTGMEMBER) 501 IPSTAT_INC(ips_notmember); 502 if (blocked == MCAST_NOTSMEMBER || 503 blocked == MCAST_MUTED) 504 UDPSTAT_INC(udps_filtermcast); 505 INP_RUNLOCK(inp); 506 continue; 507 } 508 } 509 if (last != NULL) { 510 struct mbuf *n; 511 512 n = m_copy(m, 0, M_COPYALL); 513 udp_append(last, ip, n, iphlen, &udp_in); 514 INP_RUNLOCK(last); 515 } 516 last = inp; 517 /* 518 * Don't look for additional matches if this one does 519 * not have either the SO_REUSEPORT or SO_REUSEADDR 520 * socket options set. This heuristic avoids 521 * searching through all pcbs in the common case of a 522 * non-shared port. It assumes that an application 523 * will never clear these options after setting them. 524 */ 525 if ((last->inp_socket->so_options & 526 (SO_REUSEPORT|SO_REUSEADDR)) == 0) 527 break; 528 } 529 530 if (last == NULL) { 531 /* 532 * No matching pcb found; discard datagram. (No need 533 * to send an ICMP Port Unreachable for a broadcast 534 * or multicast datgram.) 535 */ 536 UDPSTAT_INC(udps_noportbcast); 537 if (inp) 538 INP_RUNLOCK(inp); 539 INP_INFO_RUNLOCK(&V_udbinfo); 540 goto badunlocked; 541 } 542 udp_append(last, ip, m, iphlen, &udp_in); 543 INP_RUNLOCK(last); 544 INP_INFO_RUNLOCK(&V_udbinfo); 545 return; 546 } 547 548 /* 549 * Locate pcb for datagram. 550 */ 551 552 /* 553 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. 554 */ 555 if ((m->m_flags & M_IP_NEXTHOP) && 556 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) { 557 struct sockaddr_in *next_hop; 558 559 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 560 561 /* 562 * Transparently forwarded. Pretend to be the destination. 563 * Already got one like this? 564 */ 565 inp = in_pcblookup_mbuf(&V_udbinfo, ip->ip_src, uh->uh_sport, 566 ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m); 567 if (!inp) { 568 /* 569 * It's new. Try to find the ambushing socket. 570 * Because we've rewritten the destination address, 571 * any hardware-generated hash is ignored. 572 */ 573 inp = in_pcblookup(&V_udbinfo, ip->ip_src, 574 uh->uh_sport, next_hop->sin_addr, 575 next_hop->sin_port ? htons(next_hop->sin_port) : 576 uh->uh_dport, INPLOOKUP_WILDCARD | 577 INPLOOKUP_RLOCKPCB, ifp); 578 } 579 /* Remove the tag from the packet. We don't need it anymore. */ 580 m_tag_delete(m, fwd_tag); 581 m->m_flags &= ~M_IP_NEXTHOP; 582 } else 583 inp = in_pcblookup_mbuf(&V_udbinfo, ip->ip_src, uh->uh_sport, 584 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD | 585 INPLOOKUP_RLOCKPCB, ifp, m); 586 if (inp == NULL) { 587 if (udp_log_in_vain) { 588 char buf[4*sizeof "123"]; 589 590 strcpy(buf, inet_ntoa(ip->ip_dst)); 591 log(LOG_INFO, 592 "Connection attempt to UDP %s:%d from %s:%d\n", 593 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 594 ntohs(uh->uh_sport)); 595 } 596 UDPSTAT_INC(udps_noport); 597 if (m->m_flags & (M_BCAST | M_MCAST)) { 598 UDPSTAT_INC(udps_noportbcast); 599 goto badunlocked; 600 } 601 if (V_udp_blackhole) 602 goto badunlocked; 603 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 604 goto badunlocked; 605 *ip = save_ip; 606 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 607 return; 608 } 609 610 /* 611 * Check the minimum TTL for socket. 612 */ 613 INP_RLOCK_ASSERT(inp); 614 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) { 615 INP_RUNLOCK(inp); 616 m_freem(m); 617 return; 618 } 619 udp_append(inp, ip, m, iphlen, &udp_in); 620 INP_RUNLOCK(inp); 621 return; 622 623 badunlocked: 624 m_freem(m); 625 } 626 #endif /* INET */ 627 628 /* 629 * Notify a udp user of an asynchronous error; just wake up so that they can 630 * collect error status. 631 */ 632 struct inpcb * 633 udp_notify(struct inpcb *inp, int errno) 634 { 635 636 /* 637 * While udp_ctlinput() always calls udp_notify() with a read lock 638 * when invoking it directly, in_pcbnotifyall() currently uses write 639 * locks due to sharing code with TCP. For now, accept either a read 640 * or a write lock, but a read lock is sufficient. 641 */ 642 INP_LOCK_ASSERT(inp); 643 644 inp->inp_socket->so_error = errno; 645 sorwakeup(inp->inp_socket); 646 sowwakeup(inp->inp_socket); 647 return (inp); 648 } 649 650 #ifdef INET 651 void 652 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 653 { 654 struct ip *ip = vip; 655 struct udphdr *uh; 656 struct in_addr faddr; 657 struct inpcb *inp; 658 659 faddr = ((struct sockaddr_in *)sa)->sin_addr; 660 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 661 return; 662 663 /* 664 * Redirects don't need to be handled up here. 665 */ 666 if (PRC_IS_REDIRECT(cmd)) 667 return; 668 669 /* 670 * Hostdead is ugly because it goes linearly through all PCBs. 671 * 672 * XXX: We never get this from ICMP, otherwise it makes an excellent 673 * DoS attack on machines with many connections. 674 */ 675 if (cmd == PRC_HOSTDEAD) 676 ip = NULL; 677 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 678 return; 679 if (ip != NULL) { 680 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 681 inp = in_pcblookup(&V_udbinfo, faddr, uh->uh_dport, 682 ip->ip_src, uh->uh_sport, INPLOOKUP_RLOCKPCB, NULL); 683 if (inp != NULL) { 684 INP_RLOCK_ASSERT(inp); 685 if (inp->inp_socket != NULL) { 686 udp_notify(inp, inetctlerrmap[cmd]); 687 } 688 INP_RUNLOCK(inp); 689 } 690 } else 691 in_pcbnotifyall(&V_udbinfo, faddr, inetctlerrmap[cmd], 692 udp_notify); 693 } 694 #endif /* INET */ 695 696 static int 697 udp_pcblist(SYSCTL_HANDLER_ARGS) 698 { 699 int error, i, n; 700 struct inpcb *inp, **inp_list; 701 inp_gen_t gencnt; 702 struct xinpgen xig; 703 704 /* 705 * The process of preparing the PCB list is too time-consuming and 706 * resource-intensive to repeat twice on every request. 707 */ 708 if (req->oldptr == 0) { 709 n = V_udbinfo.ipi_count; 710 n += imax(n / 8, 10); 711 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb); 712 return (0); 713 } 714 715 if (req->newptr != 0) 716 return (EPERM); 717 718 /* 719 * OK, now we're committed to doing something. 720 */ 721 INP_INFO_RLOCK(&V_udbinfo); 722 gencnt = V_udbinfo.ipi_gencnt; 723 n = V_udbinfo.ipi_count; 724 INP_INFO_RUNLOCK(&V_udbinfo); 725 726 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 727 + n * sizeof(struct xinpcb)); 728 if (error != 0) 729 return (error); 730 731 xig.xig_len = sizeof xig; 732 xig.xig_count = n; 733 xig.xig_gen = gencnt; 734 xig.xig_sogen = so_gencnt; 735 error = SYSCTL_OUT(req, &xig, sizeof xig); 736 if (error) 737 return (error); 738 739 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 740 if (inp_list == 0) 741 return (ENOMEM); 742 743 INP_INFO_RLOCK(&V_udbinfo); 744 for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n; 745 inp = LIST_NEXT(inp, inp_list)) { 746 INP_WLOCK(inp); 747 if (inp->inp_gencnt <= gencnt && 748 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 749 in_pcbref(inp); 750 inp_list[i++] = inp; 751 } 752 INP_WUNLOCK(inp); 753 } 754 INP_INFO_RUNLOCK(&V_udbinfo); 755 n = i; 756 757 error = 0; 758 for (i = 0; i < n; i++) { 759 inp = inp_list[i]; 760 INP_RLOCK(inp); 761 if (inp->inp_gencnt <= gencnt) { 762 struct xinpcb xi; 763 764 bzero(&xi, sizeof(xi)); 765 xi.xi_len = sizeof xi; 766 /* XXX should avoid extra copy */ 767 bcopy(inp, &xi.xi_inp, sizeof *inp); 768 if (inp->inp_socket) 769 sotoxsocket(inp->inp_socket, &xi.xi_socket); 770 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 771 INP_RUNLOCK(inp); 772 error = SYSCTL_OUT(req, &xi, sizeof xi); 773 } else 774 INP_RUNLOCK(inp); 775 } 776 INP_INFO_WLOCK(&V_udbinfo); 777 for (i = 0; i < n; i++) { 778 inp = inp_list[i]; 779 INP_RLOCK(inp); 780 if (!in_pcbrele_rlocked(inp)) 781 INP_RUNLOCK(inp); 782 } 783 INP_INFO_WUNLOCK(&V_udbinfo); 784 785 if (!error) { 786 /* 787 * Give the user an updated idea of our state. If the 788 * generation differs from what we told her before, she knows 789 * that something happened while we were processing this 790 * request, and it might be necessary to retry. 791 */ 792 INP_INFO_RLOCK(&V_udbinfo); 793 xig.xig_gen = V_udbinfo.ipi_gencnt; 794 xig.xig_sogen = so_gencnt; 795 xig.xig_count = V_udbinfo.ipi_count; 796 INP_INFO_RUNLOCK(&V_udbinfo); 797 error = SYSCTL_OUT(req, &xig, sizeof xig); 798 } 799 free(inp_list, M_TEMP); 800 return (error); 801 } 802 803 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, 804 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0, 805 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 806 807 #ifdef INET 808 static int 809 udp_getcred(SYSCTL_HANDLER_ARGS) 810 { 811 struct xucred xuc; 812 struct sockaddr_in addrs[2]; 813 struct inpcb *inp; 814 int error; 815 816 error = priv_check(req->td, PRIV_NETINET_GETCRED); 817 if (error) 818 return (error); 819 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 820 if (error) 821 return (error); 822 inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 823 addrs[0].sin_addr, addrs[0].sin_port, 824 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL); 825 if (inp != NULL) { 826 INP_RLOCK_ASSERT(inp); 827 if (inp->inp_socket == NULL) 828 error = ENOENT; 829 if (error == 0) 830 error = cr_canseeinpcb(req->td->td_ucred, inp); 831 if (error == 0) 832 cru2x(inp->inp_cred, &xuc); 833 INP_RUNLOCK(inp); 834 } else 835 error = ENOENT; 836 if (error == 0) 837 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 838 return (error); 839 } 840 841 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 842 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 843 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 844 #endif /* INET */ 845 846 int 847 udp_ctloutput(struct socket *so, struct sockopt *sopt) 848 { 849 int error = 0, optval; 850 struct inpcb *inp; 851 #ifdef IPSEC_NAT_T 852 struct udpcb *up; 853 #endif 854 855 inp = sotoinpcb(so); 856 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 857 INP_WLOCK(inp); 858 if (sopt->sopt_level != IPPROTO_UDP) { 859 #ifdef INET6 860 if (INP_CHECK_SOCKAF(so, AF_INET6)) { 861 INP_WUNLOCK(inp); 862 error = ip6_ctloutput(so, sopt); 863 } 864 #endif 865 #if defined(INET) && defined(INET6) 866 else 867 #endif 868 #ifdef INET 869 { 870 INP_WUNLOCK(inp); 871 error = ip_ctloutput(so, sopt); 872 } 873 #endif 874 return (error); 875 } 876 877 switch (sopt->sopt_dir) { 878 case SOPT_SET: 879 switch (sopt->sopt_name) { 880 case UDP_ENCAP: 881 INP_WUNLOCK(inp); 882 error = sooptcopyin(sopt, &optval, sizeof optval, 883 sizeof optval); 884 if (error) 885 break; 886 inp = sotoinpcb(so); 887 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 888 INP_WLOCK(inp); 889 #ifdef IPSEC_NAT_T 890 up = intoudpcb(inp); 891 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 892 #endif 893 switch (optval) { 894 case 0: 895 /* Clear all UDP encap. */ 896 #ifdef IPSEC_NAT_T 897 up->u_flags &= ~UF_ESPINUDP_ALL; 898 #endif 899 break; 900 #ifdef IPSEC_NAT_T 901 case UDP_ENCAP_ESPINUDP: 902 case UDP_ENCAP_ESPINUDP_NON_IKE: 903 up->u_flags &= ~UF_ESPINUDP_ALL; 904 if (optval == UDP_ENCAP_ESPINUDP) 905 up->u_flags |= UF_ESPINUDP; 906 else if (optval == UDP_ENCAP_ESPINUDP_NON_IKE) 907 up->u_flags |= UF_ESPINUDP_NON_IKE; 908 break; 909 #endif 910 default: 911 error = EINVAL; 912 break; 913 } 914 INP_WUNLOCK(inp); 915 break; 916 default: 917 INP_WUNLOCK(inp); 918 error = ENOPROTOOPT; 919 break; 920 } 921 break; 922 case SOPT_GET: 923 switch (sopt->sopt_name) { 924 #ifdef IPSEC_NAT_T 925 case UDP_ENCAP: 926 up = intoudpcb(inp); 927 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 928 optval = up->u_flags & UF_ESPINUDP_ALL; 929 INP_WUNLOCK(inp); 930 error = sooptcopyout(sopt, &optval, sizeof optval); 931 break; 932 #endif 933 default: 934 INP_WUNLOCK(inp); 935 error = ENOPROTOOPT; 936 break; 937 } 938 break; 939 } 940 return (error); 941 } 942 943 #ifdef INET 944 #define UH_WLOCKED 2 945 #define UH_RLOCKED 1 946 #define UH_UNLOCKED 0 947 static int 948 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr, 949 struct mbuf *control, struct thread *td) 950 { 951 struct udpiphdr *ui; 952 int len = m->m_pkthdr.len; 953 struct in_addr faddr, laddr; 954 struct cmsghdr *cm; 955 struct sockaddr_in *sin, src; 956 int error = 0; 957 int ipflags; 958 u_short fport, lport; 959 int unlock_udbinfo; 960 u_char tos; 961 962 /* 963 * udp_output() may need to temporarily bind or connect the current 964 * inpcb. As such, we don't know up front whether we will need the 965 * pcbinfo lock or not. Do any work to decide what is needed up 966 * front before acquiring any locks. 967 */ 968 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 969 if (control) 970 m_freem(control); 971 m_freem(m); 972 return (EMSGSIZE); 973 } 974 975 src.sin_family = 0; 976 INP_RLOCK(inp); 977 tos = inp->inp_ip_tos; 978 if (control != NULL) { 979 /* 980 * XXX: Currently, we assume all the optional information is 981 * stored in a single mbuf. 982 */ 983 if (control->m_next) { 984 INP_RUNLOCK(inp); 985 m_freem(control); 986 m_freem(m); 987 return (EINVAL); 988 } 989 for (; control->m_len > 0; 990 control->m_data += CMSG_ALIGN(cm->cmsg_len), 991 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 992 cm = mtod(control, struct cmsghdr *); 993 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 994 || cm->cmsg_len > control->m_len) { 995 error = EINVAL; 996 break; 997 } 998 if (cm->cmsg_level != IPPROTO_IP) 999 continue; 1000 1001 switch (cm->cmsg_type) { 1002 case IP_SENDSRCADDR: 1003 if (cm->cmsg_len != 1004 CMSG_LEN(sizeof(struct in_addr))) { 1005 error = EINVAL; 1006 break; 1007 } 1008 bzero(&src, sizeof(src)); 1009 src.sin_family = AF_INET; 1010 src.sin_len = sizeof(src); 1011 src.sin_port = inp->inp_lport; 1012 src.sin_addr = 1013 *(struct in_addr *)CMSG_DATA(cm); 1014 break; 1015 1016 case IP_TOS: 1017 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) { 1018 error = EINVAL; 1019 break; 1020 } 1021 tos = *(u_char *)CMSG_DATA(cm); 1022 break; 1023 1024 default: 1025 error = ENOPROTOOPT; 1026 break; 1027 } 1028 if (error) 1029 break; 1030 } 1031 m_freem(control); 1032 } 1033 if (error) { 1034 INP_RUNLOCK(inp); 1035 m_freem(m); 1036 return (error); 1037 } 1038 1039 /* 1040 * Depending on whether or not the application has bound or connected 1041 * the socket, we may have to do varying levels of work. The optimal 1042 * case is for a connected UDP socket, as a global lock isn't 1043 * required at all. 1044 * 1045 * In order to decide which we need, we require stability of the 1046 * inpcb binding, which we ensure by acquiring a read lock on the 1047 * inpcb. This doesn't strictly follow the lock order, so we play 1048 * the trylock and retry game; note that we may end up with more 1049 * conservative locks than required the second time around, so later 1050 * assertions have to accept that. Further analysis of the number of 1051 * misses under contention is required. 1052 * 1053 * XXXRW: Check that hash locking update here is correct. 1054 */ 1055 sin = (struct sockaddr_in *)addr; 1056 if (sin != NULL && 1057 (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) { 1058 INP_RUNLOCK(inp); 1059 INP_WLOCK(inp); 1060 INP_HASH_WLOCK(&V_udbinfo); 1061 unlock_udbinfo = UH_WLOCKED; 1062 } else if ((sin != NULL && ( 1063 (sin->sin_addr.s_addr == INADDR_ANY) || 1064 (sin->sin_addr.s_addr == INADDR_BROADCAST) || 1065 (inp->inp_laddr.s_addr == INADDR_ANY) || 1066 (inp->inp_lport == 0))) || 1067 (src.sin_family == AF_INET)) { 1068 INP_HASH_RLOCK(&V_udbinfo); 1069 unlock_udbinfo = UH_RLOCKED; 1070 } else 1071 unlock_udbinfo = UH_UNLOCKED; 1072 1073 /* 1074 * If the IP_SENDSRCADDR control message was specified, override the 1075 * source address for this datagram. Its use is invalidated if the 1076 * address thus specified is incomplete or clobbers other inpcbs. 1077 */ 1078 laddr = inp->inp_laddr; 1079 lport = inp->inp_lport; 1080 if (src.sin_family == AF_INET) { 1081 INP_HASH_LOCK_ASSERT(&V_udbinfo); 1082 if ((lport == 0) || 1083 (laddr.s_addr == INADDR_ANY && 1084 src.sin_addr.s_addr == INADDR_ANY)) { 1085 error = EINVAL; 1086 goto release; 1087 } 1088 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 1089 &laddr.s_addr, &lport, td->td_ucred); 1090 if (error) 1091 goto release; 1092 } 1093 1094 /* 1095 * If a UDP socket has been connected, then a local address/port will 1096 * have been selected and bound. 1097 * 1098 * If a UDP socket has not been connected to, then an explicit 1099 * destination address must be used, in which case a local 1100 * address/port may not have been selected and bound. 1101 */ 1102 if (sin != NULL) { 1103 INP_LOCK_ASSERT(inp); 1104 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1105 error = EISCONN; 1106 goto release; 1107 } 1108 1109 /* 1110 * Jail may rewrite the destination address, so let it do 1111 * that before we use it. 1112 */ 1113 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1114 if (error) 1115 goto release; 1116 1117 /* 1118 * If a local address or port hasn't yet been selected, or if 1119 * the destination address needs to be rewritten due to using 1120 * a special INADDR_ constant, invoke in_pcbconnect_setup() 1121 * to do the heavy lifting. Once a port is selected, we 1122 * commit the binding back to the socket; we also commit the 1123 * binding of the address if in jail. 1124 * 1125 * If we already have a valid binding and we're not 1126 * requesting a destination address rewrite, use a fast path. 1127 */ 1128 if (inp->inp_laddr.s_addr == INADDR_ANY || 1129 inp->inp_lport == 0 || 1130 sin->sin_addr.s_addr == INADDR_ANY || 1131 sin->sin_addr.s_addr == INADDR_BROADCAST) { 1132 INP_HASH_LOCK_ASSERT(&V_udbinfo); 1133 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, 1134 &lport, &faddr.s_addr, &fport, NULL, 1135 td->td_ucred); 1136 if (error) 1137 goto release; 1138 1139 /* 1140 * XXXRW: Why not commit the port if the address is 1141 * !INADDR_ANY? 1142 */ 1143 /* Commit the local port if newly assigned. */ 1144 if (inp->inp_laddr.s_addr == INADDR_ANY && 1145 inp->inp_lport == 0) { 1146 INP_WLOCK_ASSERT(inp); 1147 INP_HASH_WLOCK_ASSERT(&V_udbinfo); 1148 /* 1149 * Remember addr if jailed, to prevent 1150 * rebinding. 1151 */ 1152 if (prison_flag(td->td_ucred, PR_IP4)) 1153 inp->inp_laddr = laddr; 1154 inp->inp_lport = lport; 1155 if (in_pcbinshash(inp) != 0) { 1156 inp->inp_lport = 0; 1157 error = EAGAIN; 1158 goto release; 1159 } 1160 inp->inp_flags |= INP_ANONPORT; 1161 } 1162 } else { 1163 faddr = sin->sin_addr; 1164 fport = sin->sin_port; 1165 } 1166 } else { 1167 INP_LOCK_ASSERT(inp); 1168 faddr = inp->inp_faddr; 1169 fport = inp->inp_fport; 1170 if (faddr.s_addr == INADDR_ANY) { 1171 error = ENOTCONN; 1172 goto release; 1173 } 1174 } 1175 1176 /* 1177 * Calculate data length and get a mbuf for UDP, IP, and possible 1178 * link-layer headers. Immediate slide the data pointer back forward 1179 * since we won't use that space at this layer. 1180 */ 1181 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT); 1182 if (m == NULL) { 1183 error = ENOBUFS; 1184 goto release; 1185 } 1186 m->m_data += max_linkhdr; 1187 m->m_len -= max_linkhdr; 1188 m->m_pkthdr.len -= max_linkhdr; 1189 1190 /* 1191 * Fill in mbuf with extended UDP header and addresses and length put 1192 * into network format. 1193 */ 1194 ui = mtod(m, struct udpiphdr *); 1195 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 1196 ui->ui_pr = IPPROTO_UDP; 1197 ui->ui_src = laddr; 1198 ui->ui_dst = faddr; 1199 ui->ui_sport = lport; 1200 ui->ui_dport = fport; 1201 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 1202 1203 /* 1204 * Set the Don't Fragment bit in the IP header. 1205 */ 1206 if (inp->inp_flags & INP_DONTFRAG) { 1207 struct ip *ip; 1208 1209 ip = (struct ip *)&ui->ui_i; 1210 ip->ip_off |= htons(IP_DF); 1211 } 1212 1213 ipflags = 0; 1214 if (inp->inp_socket->so_options & SO_DONTROUTE) 1215 ipflags |= IP_ROUTETOIF; 1216 if (inp->inp_socket->so_options & SO_BROADCAST) 1217 ipflags |= IP_ALLOWBROADCAST; 1218 if (inp->inp_flags & INP_ONESBCAST) 1219 ipflags |= IP_SENDONES; 1220 1221 #ifdef MAC 1222 mac_inpcb_create_mbuf(inp, m); 1223 #endif 1224 1225 /* 1226 * Set up checksum and output datagram. 1227 */ 1228 if (V_udp_cksum) { 1229 if (inp->inp_flags & INP_ONESBCAST) 1230 faddr.s_addr = INADDR_BROADCAST; 1231 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 1232 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 1233 m->m_pkthdr.csum_flags = CSUM_UDP; 1234 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 1235 } else 1236 ui->ui_sum = 0; 1237 ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len); 1238 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 1239 ((struct ip *)ui)->ip_tos = tos; /* XXX */ 1240 UDPSTAT_INC(udps_opackets); 1241 1242 if (unlock_udbinfo == UH_WLOCKED) 1243 INP_HASH_WUNLOCK(&V_udbinfo); 1244 else if (unlock_udbinfo == UH_RLOCKED) 1245 INP_HASH_RUNLOCK(&V_udbinfo); 1246 error = ip_output(m, inp->inp_options, NULL, ipflags, 1247 inp->inp_moptions, inp); 1248 if (unlock_udbinfo == UH_WLOCKED) 1249 INP_WUNLOCK(inp); 1250 else 1251 INP_RUNLOCK(inp); 1252 return (error); 1253 1254 release: 1255 if (unlock_udbinfo == UH_WLOCKED) { 1256 INP_HASH_WUNLOCK(&V_udbinfo); 1257 INP_WUNLOCK(inp); 1258 } else if (unlock_udbinfo == UH_RLOCKED) { 1259 INP_HASH_RUNLOCK(&V_udbinfo); 1260 INP_RUNLOCK(inp); 1261 } else 1262 INP_RUNLOCK(inp); 1263 m_freem(m); 1264 return (error); 1265 } 1266 1267 1268 #if defined(IPSEC) && defined(IPSEC_NAT_T) 1269 /* 1270 * Potentially decap ESP in UDP frame. Check for an ESP header 1271 * and optional marker; if present, strip the UDP header and 1272 * push the result through IPSec. 1273 * 1274 * Returns mbuf to be processed (potentially re-allocated) or 1275 * NULL if consumed and/or processed. 1276 */ 1277 static struct mbuf * 1278 udp4_espdecap(struct inpcb *inp, struct mbuf *m, int off) 1279 { 1280 size_t minlen, payload, skip, iphlen; 1281 caddr_t data; 1282 struct udpcb *up; 1283 struct m_tag *tag; 1284 struct udphdr *udphdr; 1285 struct ip *ip; 1286 1287 INP_RLOCK_ASSERT(inp); 1288 1289 /* 1290 * Pull up data so the longest case is contiguous: 1291 * IP/UDP hdr + non ESP marker + ESP hdr. 1292 */ 1293 minlen = off + sizeof(uint64_t) + sizeof(struct esp); 1294 if (minlen > m->m_pkthdr.len) 1295 minlen = m->m_pkthdr.len; 1296 if ((m = m_pullup(m, minlen)) == NULL) { 1297 IPSECSTAT_INC(ips_in_inval); 1298 return (NULL); /* Bypass caller processing. */ 1299 } 1300 data = mtod(m, caddr_t); /* Points to ip header. */ 1301 payload = m->m_len - off; /* Size of payload. */ 1302 1303 if (payload == 1 && data[off] == '\xff') 1304 return (m); /* NB: keepalive packet, no decap. */ 1305 1306 up = intoudpcb(inp); 1307 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 1308 KASSERT((up->u_flags & UF_ESPINUDP_ALL) != 0, 1309 ("u_flags 0x%x", up->u_flags)); 1310 1311 /* 1312 * Check that the payload is large enough to hold an 1313 * ESP header and compute the amount of data to remove. 1314 * 1315 * NB: the caller has already done a pullup for us. 1316 * XXX can we assume alignment and eliminate bcopys? 1317 */ 1318 if (up->u_flags & UF_ESPINUDP_NON_IKE) { 1319 /* 1320 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 1321 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, ignoring 1322 * possible AH mode non-IKE marker+non-ESP marker 1323 * from draft-ietf-ipsec-udp-encaps-00.txt. 1324 */ 1325 uint64_t marker; 1326 1327 if (payload <= sizeof(uint64_t) + sizeof(struct esp)) 1328 return (m); /* NB: no decap. */ 1329 bcopy(data + off, &marker, sizeof(uint64_t)); 1330 if (marker != 0) /* Non-IKE marker. */ 1331 return (m); /* NB: no decap. */ 1332 skip = sizeof(uint64_t) + sizeof(struct udphdr); 1333 } else { 1334 uint32_t spi; 1335 1336 if (payload <= sizeof(struct esp)) { 1337 IPSECSTAT_INC(ips_in_inval); 1338 m_freem(m); 1339 return (NULL); /* Discard. */ 1340 } 1341 bcopy(data + off, &spi, sizeof(uint32_t)); 1342 if (spi == 0) /* Non-ESP marker. */ 1343 return (m); /* NB: no decap. */ 1344 skip = sizeof(struct udphdr); 1345 } 1346 1347 /* 1348 * Setup a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember 1349 * the UDP ports. This is required if we want to select 1350 * the right SPD for multiple hosts behind same NAT. 1351 * 1352 * NB: ports are maintained in network byte order everywhere 1353 * in the NAT-T code. 1354 */ 1355 tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS, 1356 2 * sizeof(uint16_t), M_NOWAIT); 1357 if (tag == NULL) { 1358 IPSECSTAT_INC(ips_in_nomem); 1359 m_freem(m); 1360 return (NULL); /* Discard. */ 1361 } 1362 iphlen = off - sizeof(struct udphdr); 1363 udphdr = (struct udphdr *)(data + iphlen); 1364 ((uint16_t *)(tag + 1))[0] = udphdr->uh_sport; 1365 ((uint16_t *)(tag + 1))[1] = udphdr->uh_dport; 1366 m_tag_prepend(m, tag); 1367 1368 /* 1369 * Remove the UDP header (and possibly the non ESP marker) 1370 * IP header length is iphlen 1371 * Before: 1372 * <--- off ---> 1373 * +----+------+-----+ 1374 * | IP | UDP | ESP | 1375 * +----+------+-----+ 1376 * <-skip-> 1377 * After: 1378 * +----+-----+ 1379 * | IP | ESP | 1380 * +----+-----+ 1381 * <-skip-> 1382 */ 1383 ovbcopy(data, data + skip, iphlen); 1384 m_adj(m, skip); 1385 1386 ip = mtod(m, struct ip *); 1387 ip->ip_len = htons(ntohs(ip->ip_len) - skip); 1388 ip->ip_p = IPPROTO_ESP; 1389 1390 /* 1391 * We cannot yet update the cksums so clear any 1392 * h/w cksum flags as they are no longer valid. 1393 */ 1394 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) 1395 m->m_pkthdr.csum_flags &= ~(CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 1396 1397 (void) ipsec4_common_input(m, iphlen, ip->ip_p); 1398 return (NULL); /* NB: consumed, bypass processing. */ 1399 } 1400 #endif /* defined(IPSEC) && defined(IPSEC_NAT_T) */ 1401 1402 static void 1403 udp_abort(struct socket *so) 1404 { 1405 struct inpcb *inp; 1406 1407 inp = sotoinpcb(so); 1408 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 1409 INP_WLOCK(inp); 1410 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1411 INP_HASH_WLOCK(&V_udbinfo); 1412 in_pcbdisconnect(inp); 1413 inp->inp_laddr.s_addr = INADDR_ANY; 1414 INP_HASH_WUNLOCK(&V_udbinfo); 1415 soisdisconnected(so); 1416 } 1417 INP_WUNLOCK(inp); 1418 } 1419 1420 static int 1421 udp_attach(struct socket *so, int proto, struct thread *td) 1422 { 1423 struct inpcb *inp; 1424 int error; 1425 1426 inp = sotoinpcb(so); 1427 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 1428 error = soreserve(so, udp_sendspace, udp_recvspace); 1429 if (error) 1430 return (error); 1431 INP_INFO_WLOCK(&V_udbinfo); 1432 error = in_pcballoc(so, &V_udbinfo); 1433 if (error) { 1434 INP_INFO_WUNLOCK(&V_udbinfo); 1435 return (error); 1436 } 1437 1438 inp = sotoinpcb(so); 1439 inp->inp_vflag |= INP_IPV4; 1440 inp->inp_ip_ttl = V_ip_defttl; 1441 1442 error = udp_newudpcb(inp); 1443 if (error) { 1444 in_pcbdetach(inp); 1445 in_pcbfree(inp); 1446 INP_INFO_WUNLOCK(&V_udbinfo); 1447 return (error); 1448 } 1449 1450 INP_WUNLOCK(inp); 1451 INP_INFO_WUNLOCK(&V_udbinfo); 1452 return (0); 1453 } 1454 #endif /* INET */ 1455 1456 int 1457 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f) 1458 { 1459 struct inpcb *inp; 1460 struct udpcb *up; 1461 1462 KASSERT(so->so_type == SOCK_DGRAM, 1463 ("udp_set_kernel_tunneling: !dgram")); 1464 inp = sotoinpcb(so); 1465 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL")); 1466 INP_WLOCK(inp); 1467 up = intoudpcb(inp); 1468 if (up->u_tun_func != NULL) { 1469 INP_WUNLOCK(inp); 1470 return (EBUSY); 1471 } 1472 up->u_tun_func = f; 1473 INP_WUNLOCK(inp); 1474 return (0); 1475 } 1476 1477 #ifdef INET 1478 static int 1479 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1480 { 1481 struct inpcb *inp; 1482 int error; 1483 1484 inp = sotoinpcb(so); 1485 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1486 INP_WLOCK(inp); 1487 INP_HASH_WLOCK(&V_udbinfo); 1488 error = in_pcbbind(inp, nam, td->td_ucred); 1489 INP_HASH_WUNLOCK(&V_udbinfo); 1490 INP_WUNLOCK(inp); 1491 return (error); 1492 } 1493 1494 static void 1495 udp_close(struct socket *so) 1496 { 1497 struct inpcb *inp; 1498 1499 inp = sotoinpcb(so); 1500 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1501 INP_WLOCK(inp); 1502 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1503 INP_HASH_WLOCK(&V_udbinfo); 1504 in_pcbdisconnect(inp); 1505 inp->inp_laddr.s_addr = INADDR_ANY; 1506 INP_HASH_WUNLOCK(&V_udbinfo); 1507 soisdisconnected(so); 1508 } 1509 INP_WUNLOCK(inp); 1510 } 1511 1512 static int 1513 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1514 { 1515 struct inpcb *inp; 1516 int error; 1517 struct sockaddr_in *sin; 1518 1519 inp = sotoinpcb(so); 1520 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1521 INP_WLOCK(inp); 1522 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1523 INP_WUNLOCK(inp); 1524 return (EISCONN); 1525 } 1526 sin = (struct sockaddr_in *)nam; 1527 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1528 if (error != 0) { 1529 INP_WUNLOCK(inp); 1530 return (error); 1531 } 1532 INP_HASH_WLOCK(&V_udbinfo); 1533 error = in_pcbconnect(inp, nam, td->td_ucred); 1534 INP_HASH_WUNLOCK(&V_udbinfo); 1535 if (error == 0) 1536 soisconnected(so); 1537 INP_WUNLOCK(inp); 1538 return (error); 1539 } 1540 1541 static void 1542 udp_detach(struct socket *so) 1543 { 1544 struct inpcb *inp; 1545 struct udpcb *up; 1546 1547 inp = sotoinpcb(so); 1548 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1549 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY, 1550 ("udp_detach: not disconnected")); 1551 INP_INFO_WLOCK(&V_udbinfo); 1552 INP_WLOCK(inp); 1553 up = intoudpcb(inp); 1554 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 1555 inp->inp_ppcb = NULL; 1556 in_pcbdetach(inp); 1557 in_pcbfree(inp); 1558 INP_INFO_WUNLOCK(&V_udbinfo); 1559 udp_discardcb(up); 1560 } 1561 1562 static int 1563 udp_disconnect(struct socket *so) 1564 { 1565 struct inpcb *inp; 1566 1567 inp = sotoinpcb(so); 1568 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1569 INP_WLOCK(inp); 1570 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1571 INP_WUNLOCK(inp); 1572 return (ENOTCONN); 1573 } 1574 INP_HASH_WLOCK(&V_udbinfo); 1575 in_pcbdisconnect(inp); 1576 inp->inp_laddr.s_addr = INADDR_ANY; 1577 INP_HASH_WUNLOCK(&V_udbinfo); 1578 SOCK_LOCK(so); 1579 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1580 SOCK_UNLOCK(so); 1581 INP_WUNLOCK(inp); 1582 return (0); 1583 } 1584 1585 static int 1586 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1587 struct mbuf *control, struct thread *td) 1588 { 1589 struct inpcb *inp; 1590 1591 inp = sotoinpcb(so); 1592 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1593 return (udp_output(inp, m, addr, control, td)); 1594 } 1595 #endif /* INET */ 1596 1597 int 1598 udp_shutdown(struct socket *so) 1599 { 1600 struct inpcb *inp; 1601 1602 inp = sotoinpcb(so); 1603 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1604 INP_WLOCK(inp); 1605 socantsendmore(so); 1606 INP_WUNLOCK(inp); 1607 return (0); 1608 } 1609 1610 #ifdef INET 1611 struct pr_usrreqs udp_usrreqs = { 1612 .pru_abort = udp_abort, 1613 .pru_attach = udp_attach, 1614 .pru_bind = udp_bind, 1615 .pru_connect = udp_connect, 1616 .pru_control = in_control, 1617 .pru_detach = udp_detach, 1618 .pru_disconnect = udp_disconnect, 1619 .pru_peeraddr = in_getpeeraddr, 1620 .pru_send = udp_send, 1621 .pru_soreceive = soreceive_dgram, 1622 .pru_sosend = sosend_dgram, 1623 .pru_shutdown = udp_shutdown, 1624 .pru_sockaddr = in_getsockaddr, 1625 .pru_sosetlabel = in_pcbsosetlabel, 1626 .pru_close = udp_close, 1627 }; 1628 #endif /* INET */ 1629