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/sdt.h> 58 #include <sys/signalvar.h> 59 #include <sys/socket.h> 60 #include <sys/socketvar.h> 61 #include <sys/sx.h> 62 #include <sys/sysctl.h> 63 #include <sys/syslog.h> 64 #include <sys/systm.h> 65 66 #include <vm/uma.h> 67 68 #include <net/if.h> 69 #include <net/if_var.h> 70 #include <net/route.h> 71 72 #include <netinet/in.h> 73 #include <netinet/in_kdtrace.h> 74 #include <netinet/in_pcb.h> 75 #include <netinet/in_systm.h> 76 #include <netinet/in_var.h> 77 #include <netinet/ip.h> 78 #ifdef INET6 79 #include <netinet/ip6.h> 80 #endif 81 #include <netinet/ip_icmp.h> 82 #include <netinet/icmp_var.h> 83 #include <netinet/ip_var.h> 84 #include <netinet/ip_options.h> 85 #ifdef INET6 86 #include <netinet6/ip6_var.h> 87 #endif 88 #include <netinet/udp.h> 89 #include <netinet/udp_var.h> 90 91 #ifdef IPSEC 92 #include <netipsec/ipsec.h> 93 #include <netipsec/esp.h> 94 #endif 95 96 #include <machine/in_cksum.h> 97 98 #include <security/mac/mac_framework.h> 99 100 /* 101 * UDP protocol implementation. 102 * Per RFC 768, August, 1980. 103 */ 104 105 /* 106 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums 107 * removes the only data integrity mechanism for packets and malformed 108 * packets that would otherwise be discarded due to bad checksums, and may 109 * cause problems (especially for NFS data blocks). 110 */ 111 VNET_DEFINE(int, udp_cksum) = 1; 112 SYSCTL_VNET_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, 113 &VNET_NAME(udp_cksum), 0, "compute udp checksum"); 114 115 int udp_log_in_vain = 0; 116 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW, 117 &udp_log_in_vain, 0, "Log all incoming UDP packets"); 118 119 VNET_DEFINE(int, udp_blackhole) = 0; 120 SYSCTL_VNET_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW, 121 &VNET_NAME(udp_blackhole), 0, 122 "Do not send port unreachables for refused connects"); 123 124 u_long udp_sendspace = 9216; /* really max datagram size */ 125 /* 40 1K datagrams */ 126 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 127 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 128 129 u_long udp_recvspace = 40 * (1024 + 130 #ifdef INET6 131 sizeof(struct sockaddr_in6) 132 #else 133 sizeof(struct sockaddr_in) 134 #endif 135 ); 136 137 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 138 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 139 140 VNET_DEFINE(struct inpcbhead, udb); /* from udp_var.h */ 141 VNET_DEFINE(struct inpcbinfo, udbinfo); 142 static VNET_DEFINE(uma_zone_t, udpcb_zone); 143 #define V_udpcb_zone VNET(udpcb_zone) 144 145 #ifndef UDBHASHSIZE 146 #define UDBHASHSIZE 128 147 #endif 148 149 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat); /* from udp_var.h */ 150 VNET_PCPUSTAT_SYSINIT(udpstat); 151 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat, 152 udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)"); 153 154 #ifdef VIMAGE 155 VNET_PCPUSTAT_SYSUNINIT(udpstat); 156 #endif /* VIMAGE */ 157 #ifdef INET 158 static void udp_detach(struct socket *so); 159 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 160 struct mbuf *, struct thread *); 161 #endif 162 163 #ifdef IPSEC 164 #ifdef IPSEC_NAT_T 165 #define UF_ESPINUDP_ALL (UF_ESPINUDP_NON_IKE|UF_ESPINUDP) 166 #ifdef INET 167 static struct mbuf *udp4_espdecap(struct inpcb *, struct mbuf *, int); 168 #endif 169 #endif /* IPSEC_NAT_T */ 170 #endif /* IPSEC */ 171 172 static void 173 udp_zone_change(void *tag) 174 { 175 176 uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets); 177 uma_zone_set_max(V_udpcb_zone, maxsockets); 178 } 179 180 static int 181 udp_inpcb_init(void *mem, int size, int flags) 182 { 183 struct inpcb *inp; 184 185 inp = mem; 186 INP_LOCK_INIT(inp, "inp", "udpinp"); 187 return (0); 188 } 189 190 void 191 udp_init(void) 192 { 193 194 in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE, 195 "udp_inpcb", udp_inpcb_init, NULL, UMA_ZONE_NOFREE, 196 IPI_HASHFIELDS_2TUPLE); 197 V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb), 198 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 199 uma_zone_set_max(V_udpcb_zone, maxsockets); 200 uma_zone_set_warning(V_udpcb_zone, "kern.ipc.maxsockets limit reached"); 201 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL, 202 EVENTHANDLER_PRI_ANY); 203 } 204 205 /* 206 * Kernel module interface for updating udpstat. The argument is an index 207 * into udpstat treated as an array of u_long. While this encodes the 208 * general layout of udpstat into the caller, it doesn't encode its location, 209 * so that future changes to add, for example, per-CPU stats support won't 210 * cause binary compatibility problems for kernel modules. 211 */ 212 void 213 kmod_udpstat_inc(int statnum) 214 { 215 216 counter_u64_add(VNET(udpstat)[statnum], 1); 217 } 218 219 int 220 udp_newudpcb(struct inpcb *inp) 221 { 222 struct udpcb *up; 223 224 up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO); 225 if (up == NULL) 226 return (ENOBUFS); 227 inp->inp_ppcb = up; 228 return (0); 229 } 230 231 void 232 udp_discardcb(struct udpcb *up) 233 { 234 235 uma_zfree(V_udpcb_zone, up); 236 } 237 238 #ifdef VIMAGE 239 void 240 udp_destroy(void) 241 { 242 243 in_pcbinfo_destroy(&V_udbinfo); 244 uma_zdestroy(V_udpcb_zone); 245 } 246 #endif 247 248 #ifdef INET 249 /* 250 * Subroutine of udp_input(), which appends the provided mbuf chain to the 251 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 252 * contains the source address. If the socket ends up being an IPv6 socket, 253 * udp_append() will convert to a sockaddr_in6 before passing the address 254 * into the socket code. 255 */ 256 static void 257 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off, 258 struct sockaddr_in *udp_in) 259 { 260 struct sockaddr *append_sa; 261 struct socket *so; 262 struct mbuf *opts = 0; 263 #ifdef INET6 264 struct sockaddr_in6 udp_in6; 265 #endif 266 struct udpcb *up; 267 268 INP_LOCK_ASSERT(inp); 269 270 /* 271 * Engage the tunneling protocol. 272 */ 273 up = intoudpcb(inp); 274 if (up->u_tun_func != NULL) { 275 (*up->u_tun_func)(n, off, inp); 276 return; 277 } 278 279 if (n == NULL) 280 return; 281 282 off += sizeof(struct udphdr); 283 284 #ifdef IPSEC 285 /* Check AH/ESP integrity. */ 286 if (ipsec4_in_reject(n, inp)) { 287 m_freem(n); 288 IPSECSTAT_INC(ips_in_polvio); 289 return; 290 } 291 #ifdef IPSEC_NAT_T 292 up = intoudpcb(inp); 293 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 294 if (up->u_flags & UF_ESPINUDP_ALL) { /* IPSec UDP encaps. */ 295 n = udp4_espdecap(inp, n, off); 296 if (n == NULL) /* Consumed. */ 297 return; 298 } 299 #endif /* IPSEC_NAT_T */ 300 #endif /* IPSEC */ 301 #ifdef MAC 302 if (mac_inpcb_check_deliver(inp, n) != 0) { 303 m_freem(n); 304 return; 305 } 306 #endif /* MAC */ 307 if (inp->inp_flags & INP_CONTROLOPTS || 308 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 309 #ifdef INET6 310 if (inp->inp_vflag & INP_IPV6) 311 (void)ip6_savecontrol_v4(inp, n, &opts, NULL); 312 else 313 #endif /* INET6 */ 314 ip_savecontrol(inp, &opts, ip, n); 315 } 316 #ifdef INET6 317 if (inp->inp_vflag & INP_IPV6) { 318 bzero(&udp_in6, sizeof(udp_in6)); 319 udp_in6.sin6_len = sizeof(udp_in6); 320 udp_in6.sin6_family = AF_INET6; 321 in6_sin_2_v4mapsin6(udp_in, &udp_in6); 322 append_sa = (struct sockaddr *)&udp_in6; 323 } else 324 #endif /* INET6 */ 325 append_sa = (struct sockaddr *)udp_in; 326 m_adj(n, off); 327 328 so = inp->inp_socket; 329 SOCKBUF_LOCK(&so->so_rcv); 330 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 331 SOCKBUF_UNLOCK(&so->so_rcv); 332 m_freem(n); 333 if (opts) 334 m_freem(opts); 335 UDPSTAT_INC(udps_fullsock); 336 } else 337 sorwakeup_locked(so); 338 } 339 340 void 341 udp_input(struct mbuf *m, int off) 342 { 343 int iphlen = off; 344 struct ip *ip; 345 struct udphdr *uh; 346 struct ifnet *ifp; 347 struct inpcb *inp; 348 uint16_t len, ip_len; 349 struct ip save_ip; 350 struct sockaddr_in udp_in; 351 struct m_tag *fwd_tag; 352 353 ifp = m->m_pkthdr.rcvif; 354 UDPSTAT_INC(udps_ipackets); 355 356 /* 357 * Strip IP options, if any; should skip this, make available to 358 * user, and use on returned packets, but we don't yet have a way to 359 * check the checksum with options still present. 360 */ 361 if (iphlen > sizeof (struct ip)) { 362 ip_stripoptions(m); 363 iphlen = sizeof(struct ip); 364 } 365 366 /* 367 * Get IP and UDP header together in first mbuf. 368 */ 369 ip = mtod(m, struct ip *); 370 if (m->m_len < iphlen + sizeof(struct udphdr)) { 371 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 372 UDPSTAT_INC(udps_hdrops); 373 return; 374 } 375 ip = mtod(m, struct ip *); 376 } 377 uh = (struct udphdr *)((caddr_t)ip + iphlen); 378 379 /* 380 * Destination port of 0 is illegal, based on RFC768. 381 */ 382 if (uh->uh_dport == 0) 383 goto badunlocked; 384 385 /* 386 * Construct sockaddr format source address. Stuff source address 387 * and datagram in user buffer. 388 */ 389 bzero(&udp_in, sizeof(udp_in)); 390 udp_in.sin_len = sizeof(udp_in); 391 udp_in.sin_family = AF_INET; 392 udp_in.sin_port = uh->uh_sport; 393 udp_in.sin_addr = ip->ip_src; 394 395 /* 396 * Make mbuf data length reflect UDP length. If not enough data to 397 * reflect UDP length, drop. 398 */ 399 len = ntohs((u_short)uh->uh_ulen); 400 ip_len = ntohs(ip->ip_len) - iphlen; 401 if (ip_len != len) { 402 if (len > ip_len || len < sizeof(struct udphdr)) { 403 UDPSTAT_INC(udps_badlen); 404 goto badunlocked; 405 } 406 m_adj(m, len - ip_len); 407 } 408 409 /* 410 * Save a copy of the IP header in case we want restore it for 411 * sending an ICMP error message in response. 412 */ 413 if (!V_udp_blackhole) 414 save_ip = *ip; 415 else 416 memset(&save_ip, 0, sizeof(save_ip)); 417 418 /* 419 * Checksum extended UDP header and data. 420 */ 421 if (uh->uh_sum) { 422 u_short uh_sum; 423 424 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 425 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 426 uh_sum = m->m_pkthdr.csum_data; 427 else 428 uh_sum = in_pseudo(ip->ip_src.s_addr, 429 ip->ip_dst.s_addr, htonl((u_short)len + 430 m->m_pkthdr.csum_data + IPPROTO_UDP)); 431 uh_sum ^= 0xffff; 432 } else { 433 char b[9]; 434 435 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 436 bzero(((struct ipovly *)ip)->ih_x1, 9); 437 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 438 uh_sum = in_cksum(m, len + sizeof (struct ip)); 439 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 440 } 441 if (uh_sum) { 442 UDPSTAT_INC(udps_badsum); 443 m_freem(m); 444 return; 445 } 446 } else 447 UDPSTAT_INC(udps_nosum); 448 449 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 450 in_broadcast(ip->ip_dst, ifp)) { 451 struct inpcb *last; 452 struct ip_moptions *imo; 453 454 INP_INFO_RLOCK(&V_udbinfo); 455 last = NULL; 456 LIST_FOREACH(inp, &V_udb, inp_list) { 457 if (inp->inp_lport != uh->uh_dport) 458 continue; 459 #ifdef INET6 460 if ((inp->inp_vflag & INP_IPV4) == 0) 461 continue; 462 #endif 463 if (inp->inp_laddr.s_addr != INADDR_ANY && 464 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 465 continue; 466 if (inp->inp_faddr.s_addr != INADDR_ANY && 467 inp->inp_faddr.s_addr != ip->ip_src.s_addr) 468 continue; 469 if (inp->inp_fport != 0 && 470 inp->inp_fport != uh->uh_sport) 471 continue; 472 473 INP_RLOCK(inp); 474 475 /* 476 * XXXRW: Because we weren't holding either the inpcb 477 * or the hash lock when we checked for a match 478 * before, we should probably recheck now that the 479 * inpcb lock is held. 480 */ 481 482 /* 483 * Handle socket delivery policy for any-source 484 * and source-specific multicast. [RFC3678] 485 */ 486 imo = inp->inp_moptions; 487 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 488 struct sockaddr_in group; 489 int blocked; 490 if (imo == NULL) { 491 INP_RUNLOCK(inp); 492 continue; 493 } 494 bzero(&group, sizeof(struct sockaddr_in)); 495 group.sin_len = sizeof(struct sockaddr_in); 496 group.sin_family = AF_INET; 497 group.sin_addr = ip->ip_dst; 498 499 blocked = imo_multi_filter(imo, ifp, 500 (struct sockaddr *)&group, 501 (struct sockaddr *)&udp_in); 502 if (blocked != MCAST_PASS) { 503 if (blocked == MCAST_NOTGMEMBER) 504 IPSTAT_INC(ips_notmember); 505 if (blocked == MCAST_NOTSMEMBER || 506 blocked == MCAST_MUTED) 507 UDPSTAT_INC(udps_filtermcast); 508 INP_RUNLOCK(inp); 509 continue; 510 } 511 } 512 if (last != NULL) { 513 struct mbuf *n; 514 515 n = m_copy(m, 0, M_COPYALL); 516 udp_append(last, ip, n, iphlen, &udp_in); 517 INP_RUNLOCK(last); 518 } 519 last = inp; 520 /* 521 * Don't look for additional matches if this one does 522 * not have either the SO_REUSEPORT or SO_REUSEADDR 523 * socket options set. This heuristic avoids 524 * searching through all pcbs in the common case of a 525 * non-shared port. It assumes that an application 526 * will never clear these options after setting them. 527 */ 528 if ((last->inp_socket->so_options & 529 (SO_REUSEPORT|SO_REUSEADDR)) == 0) 530 break; 531 } 532 533 if (last == NULL) { 534 /* 535 * No matching pcb found; discard datagram. (No need 536 * to send an ICMP Port Unreachable for a broadcast 537 * or multicast datgram.) 538 */ 539 UDPSTAT_INC(udps_noportbcast); 540 if (inp) 541 INP_RUNLOCK(inp); 542 INP_INFO_RUNLOCK(&V_udbinfo); 543 goto badunlocked; 544 } 545 udp_append(last, ip, m, iphlen, &udp_in); 546 INP_RUNLOCK(last); 547 INP_INFO_RUNLOCK(&V_udbinfo); 548 return; 549 } 550 551 /* 552 * Locate pcb for datagram. 553 */ 554 555 /* 556 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. 557 */ 558 if ((m->m_flags & M_IP_NEXTHOP) && 559 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) { 560 struct sockaddr_in *next_hop; 561 562 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 563 564 /* 565 * Transparently forwarded. Pretend to be the destination. 566 * Already got one like this? 567 */ 568 inp = in_pcblookup_mbuf(&V_udbinfo, ip->ip_src, uh->uh_sport, 569 ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m); 570 if (!inp) { 571 /* 572 * It's new. Try to find the ambushing socket. 573 * Because we've rewritten the destination address, 574 * any hardware-generated hash is ignored. 575 */ 576 inp = in_pcblookup(&V_udbinfo, ip->ip_src, 577 uh->uh_sport, next_hop->sin_addr, 578 next_hop->sin_port ? htons(next_hop->sin_port) : 579 uh->uh_dport, INPLOOKUP_WILDCARD | 580 INPLOOKUP_RLOCKPCB, ifp); 581 } 582 /* Remove the tag from the packet. We don't need it anymore. */ 583 m_tag_delete(m, fwd_tag); 584 m->m_flags &= ~M_IP_NEXTHOP; 585 } else 586 inp = in_pcblookup_mbuf(&V_udbinfo, ip->ip_src, uh->uh_sport, 587 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD | 588 INPLOOKUP_RLOCKPCB, ifp, m); 589 if (inp == NULL) { 590 if (udp_log_in_vain) { 591 char buf[4*sizeof "123"]; 592 593 strcpy(buf, inet_ntoa(ip->ip_dst)); 594 log(LOG_INFO, 595 "Connection attempt to UDP %s:%d from %s:%d\n", 596 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 597 ntohs(uh->uh_sport)); 598 } 599 UDPSTAT_INC(udps_noport); 600 if (m->m_flags & (M_BCAST | M_MCAST)) { 601 UDPSTAT_INC(udps_noportbcast); 602 goto badunlocked; 603 } 604 if (V_udp_blackhole) 605 goto badunlocked; 606 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 607 goto badunlocked; 608 *ip = save_ip; 609 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 610 return; 611 } 612 613 /* 614 * Check the minimum TTL for socket. 615 */ 616 INP_RLOCK_ASSERT(inp); 617 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) { 618 INP_RUNLOCK(inp); 619 m_freem(m); 620 return; 621 } 622 623 UDP_PROBE(receive, NULL, inp, ip, inp, uh); 624 udp_append(inp, ip, m, iphlen, &udp_in); 625 INP_RUNLOCK(inp); 626 return; 627 628 badunlocked: 629 m_freem(m); 630 } 631 #endif /* INET */ 632 633 /* 634 * Notify a udp user of an asynchronous error; just wake up so that they can 635 * collect error status. 636 */ 637 struct inpcb * 638 udp_notify(struct inpcb *inp, int errno) 639 { 640 641 /* 642 * While udp_ctlinput() always calls udp_notify() with a read lock 643 * when invoking it directly, in_pcbnotifyall() currently uses write 644 * locks due to sharing code with TCP. For now, accept either a read 645 * or a write lock, but a read lock is sufficient. 646 */ 647 INP_LOCK_ASSERT(inp); 648 649 inp->inp_socket->so_error = errno; 650 sorwakeup(inp->inp_socket); 651 sowwakeup(inp->inp_socket); 652 return (inp); 653 } 654 655 #ifdef INET 656 void 657 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 658 { 659 struct ip *ip = vip; 660 struct udphdr *uh; 661 struct in_addr faddr; 662 struct inpcb *inp; 663 664 faddr = ((struct sockaddr_in *)sa)->sin_addr; 665 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 666 return; 667 668 /* 669 * Redirects don't need to be handled up here. 670 */ 671 if (PRC_IS_REDIRECT(cmd)) 672 return; 673 674 /* 675 * Hostdead is ugly because it goes linearly through all PCBs. 676 * 677 * XXX: We never get this from ICMP, otherwise it makes an excellent 678 * DoS attack on machines with many connections. 679 */ 680 if (cmd == PRC_HOSTDEAD) 681 ip = NULL; 682 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 683 return; 684 if (ip != NULL) { 685 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 686 inp = in_pcblookup(&V_udbinfo, faddr, uh->uh_dport, 687 ip->ip_src, uh->uh_sport, INPLOOKUP_RLOCKPCB, NULL); 688 if (inp != NULL) { 689 INP_RLOCK_ASSERT(inp); 690 if (inp->inp_socket != NULL) { 691 udp_notify(inp, inetctlerrmap[cmd]); 692 } 693 INP_RUNLOCK(inp); 694 } 695 } else 696 in_pcbnotifyall(&V_udbinfo, faddr, inetctlerrmap[cmd], 697 udp_notify); 698 } 699 #endif /* INET */ 700 701 static int 702 udp_pcblist(SYSCTL_HANDLER_ARGS) 703 { 704 int error, i, n; 705 struct inpcb *inp, **inp_list; 706 inp_gen_t gencnt; 707 struct xinpgen xig; 708 709 /* 710 * The process of preparing the PCB list is too time-consuming and 711 * resource-intensive to repeat twice on every request. 712 */ 713 if (req->oldptr == 0) { 714 n = V_udbinfo.ipi_count; 715 n += imax(n / 8, 10); 716 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb); 717 return (0); 718 } 719 720 if (req->newptr != 0) 721 return (EPERM); 722 723 /* 724 * OK, now we're committed to doing something. 725 */ 726 INP_INFO_RLOCK(&V_udbinfo); 727 gencnt = V_udbinfo.ipi_gencnt; 728 n = V_udbinfo.ipi_count; 729 INP_INFO_RUNLOCK(&V_udbinfo); 730 731 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 732 + n * sizeof(struct xinpcb)); 733 if (error != 0) 734 return (error); 735 736 xig.xig_len = sizeof xig; 737 xig.xig_count = n; 738 xig.xig_gen = gencnt; 739 xig.xig_sogen = so_gencnt; 740 error = SYSCTL_OUT(req, &xig, sizeof xig); 741 if (error) 742 return (error); 743 744 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 745 if (inp_list == 0) 746 return (ENOMEM); 747 748 INP_INFO_RLOCK(&V_udbinfo); 749 for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n; 750 inp = LIST_NEXT(inp, inp_list)) { 751 INP_WLOCK(inp); 752 if (inp->inp_gencnt <= gencnt && 753 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 754 in_pcbref(inp); 755 inp_list[i++] = inp; 756 } 757 INP_WUNLOCK(inp); 758 } 759 INP_INFO_RUNLOCK(&V_udbinfo); 760 n = i; 761 762 error = 0; 763 for (i = 0; i < n; i++) { 764 inp = inp_list[i]; 765 INP_RLOCK(inp); 766 if (inp->inp_gencnt <= gencnt) { 767 struct xinpcb xi; 768 769 bzero(&xi, sizeof(xi)); 770 xi.xi_len = sizeof xi; 771 /* XXX should avoid extra copy */ 772 bcopy(inp, &xi.xi_inp, sizeof *inp); 773 if (inp->inp_socket) 774 sotoxsocket(inp->inp_socket, &xi.xi_socket); 775 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 776 INP_RUNLOCK(inp); 777 error = SYSCTL_OUT(req, &xi, sizeof xi); 778 } else 779 INP_RUNLOCK(inp); 780 } 781 INP_INFO_WLOCK(&V_udbinfo); 782 for (i = 0; i < n; i++) { 783 inp = inp_list[i]; 784 INP_RLOCK(inp); 785 if (!in_pcbrele_rlocked(inp)) 786 INP_RUNLOCK(inp); 787 } 788 INP_INFO_WUNLOCK(&V_udbinfo); 789 790 if (!error) { 791 /* 792 * Give the user an updated idea of our state. If the 793 * generation differs from what we told her before, she knows 794 * that something happened while we were processing this 795 * request, and it might be necessary to retry. 796 */ 797 INP_INFO_RLOCK(&V_udbinfo); 798 xig.xig_gen = V_udbinfo.ipi_gencnt; 799 xig.xig_sogen = so_gencnt; 800 xig.xig_count = V_udbinfo.ipi_count; 801 INP_INFO_RUNLOCK(&V_udbinfo); 802 error = SYSCTL_OUT(req, &xig, sizeof xig); 803 } 804 free(inp_list, M_TEMP); 805 return (error); 806 } 807 808 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, 809 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0, 810 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 811 812 #ifdef INET 813 static int 814 udp_getcred(SYSCTL_HANDLER_ARGS) 815 { 816 struct xucred xuc; 817 struct sockaddr_in addrs[2]; 818 struct inpcb *inp; 819 int error; 820 821 error = priv_check(req->td, PRIV_NETINET_GETCRED); 822 if (error) 823 return (error); 824 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 825 if (error) 826 return (error); 827 inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 828 addrs[0].sin_addr, addrs[0].sin_port, 829 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL); 830 if (inp != NULL) { 831 INP_RLOCK_ASSERT(inp); 832 if (inp->inp_socket == NULL) 833 error = ENOENT; 834 if (error == 0) 835 error = cr_canseeinpcb(req->td->td_ucred, inp); 836 if (error == 0) 837 cru2x(inp->inp_cred, &xuc); 838 INP_RUNLOCK(inp); 839 } else 840 error = ENOENT; 841 if (error == 0) 842 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 843 return (error); 844 } 845 846 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 847 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 848 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 849 #endif /* INET */ 850 851 int 852 udp_ctloutput(struct socket *so, struct sockopt *sopt) 853 { 854 int error = 0, optval; 855 struct inpcb *inp; 856 #ifdef IPSEC_NAT_T 857 struct udpcb *up; 858 #endif 859 860 inp = sotoinpcb(so); 861 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 862 INP_WLOCK(inp); 863 if (sopt->sopt_level != IPPROTO_UDP) { 864 #ifdef INET6 865 if (INP_CHECK_SOCKAF(so, AF_INET6)) { 866 INP_WUNLOCK(inp); 867 error = ip6_ctloutput(so, sopt); 868 } 869 #endif 870 #if defined(INET) && defined(INET6) 871 else 872 #endif 873 #ifdef INET 874 { 875 INP_WUNLOCK(inp); 876 error = ip_ctloutput(so, sopt); 877 } 878 #endif 879 return (error); 880 } 881 882 switch (sopt->sopt_dir) { 883 case SOPT_SET: 884 switch (sopt->sopt_name) { 885 case UDP_ENCAP: 886 INP_WUNLOCK(inp); 887 error = sooptcopyin(sopt, &optval, sizeof optval, 888 sizeof optval); 889 if (error) 890 break; 891 inp = sotoinpcb(so); 892 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 893 INP_WLOCK(inp); 894 #ifdef IPSEC_NAT_T 895 up = intoudpcb(inp); 896 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 897 #endif 898 switch (optval) { 899 case 0: 900 /* Clear all UDP encap. */ 901 #ifdef IPSEC_NAT_T 902 up->u_flags &= ~UF_ESPINUDP_ALL; 903 #endif 904 break; 905 #ifdef IPSEC_NAT_T 906 case UDP_ENCAP_ESPINUDP: 907 case UDP_ENCAP_ESPINUDP_NON_IKE: 908 up->u_flags &= ~UF_ESPINUDP_ALL; 909 if (optval == UDP_ENCAP_ESPINUDP) 910 up->u_flags |= UF_ESPINUDP; 911 else if (optval == UDP_ENCAP_ESPINUDP_NON_IKE) 912 up->u_flags |= UF_ESPINUDP_NON_IKE; 913 break; 914 #endif 915 default: 916 error = EINVAL; 917 break; 918 } 919 INP_WUNLOCK(inp); 920 break; 921 default: 922 INP_WUNLOCK(inp); 923 error = ENOPROTOOPT; 924 break; 925 } 926 break; 927 case SOPT_GET: 928 switch (sopt->sopt_name) { 929 #ifdef IPSEC_NAT_T 930 case UDP_ENCAP: 931 up = intoudpcb(inp); 932 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 933 optval = up->u_flags & UF_ESPINUDP_ALL; 934 INP_WUNLOCK(inp); 935 error = sooptcopyout(sopt, &optval, sizeof optval); 936 break; 937 #endif 938 default: 939 INP_WUNLOCK(inp); 940 error = ENOPROTOOPT; 941 break; 942 } 943 break; 944 } 945 return (error); 946 } 947 948 #ifdef INET 949 #define UH_WLOCKED 2 950 #define UH_RLOCKED 1 951 #define UH_UNLOCKED 0 952 static int 953 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr, 954 struct mbuf *control, struct thread *td) 955 { 956 struct udpiphdr *ui; 957 int len = m->m_pkthdr.len; 958 struct in_addr faddr, laddr; 959 struct cmsghdr *cm; 960 struct sockaddr_in *sin, src; 961 int error = 0; 962 int ipflags; 963 u_short fport, lport; 964 int unlock_udbinfo; 965 u_char tos; 966 967 /* 968 * udp_output() may need to temporarily bind or connect the current 969 * inpcb. As such, we don't know up front whether we will need the 970 * pcbinfo lock or not. Do any work to decide what is needed up 971 * front before acquiring any locks. 972 */ 973 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 974 if (control) 975 m_freem(control); 976 m_freem(m); 977 return (EMSGSIZE); 978 } 979 980 src.sin_family = 0; 981 INP_RLOCK(inp); 982 tos = inp->inp_ip_tos; 983 if (control != NULL) { 984 /* 985 * XXX: Currently, we assume all the optional information is 986 * stored in a single mbuf. 987 */ 988 if (control->m_next) { 989 INP_RUNLOCK(inp); 990 m_freem(control); 991 m_freem(m); 992 return (EINVAL); 993 } 994 for (; control->m_len > 0; 995 control->m_data += CMSG_ALIGN(cm->cmsg_len), 996 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 997 cm = mtod(control, struct cmsghdr *); 998 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 999 || cm->cmsg_len > control->m_len) { 1000 error = EINVAL; 1001 break; 1002 } 1003 if (cm->cmsg_level != IPPROTO_IP) 1004 continue; 1005 1006 switch (cm->cmsg_type) { 1007 case IP_SENDSRCADDR: 1008 if (cm->cmsg_len != 1009 CMSG_LEN(sizeof(struct in_addr))) { 1010 error = EINVAL; 1011 break; 1012 } 1013 bzero(&src, sizeof(src)); 1014 src.sin_family = AF_INET; 1015 src.sin_len = sizeof(src); 1016 src.sin_port = inp->inp_lport; 1017 src.sin_addr = 1018 *(struct in_addr *)CMSG_DATA(cm); 1019 break; 1020 1021 case IP_TOS: 1022 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) { 1023 error = EINVAL; 1024 break; 1025 } 1026 tos = *(u_char *)CMSG_DATA(cm); 1027 break; 1028 1029 default: 1030 error = ENOPROTOOPT; 1031 break; 1032 } 1033 if (error) 1034 break; 1035 } 1036 m_freem(control); 1037 } 1038 if (error) { 1039 INP_RUNLOCK(inp); 1040 m_freem(m); 1041 return (error); 1042 } 1043 1044 /* 1045 * Depending on whether or not the application has bound or connected 1046 * the socket, we may have to do varying levels of work. The optimal 1047 * case is for a connected UDP socket, as a global lock isn't 1048 * required at all. 1049 * 1050 * In order to decide which we need, we require stability of the 1051 * inpcb binding, which we ensure by acquiring a read lock on the 1052 * inpcb. This doesn't strictly follow the lock order, so we play 1053 * the trylock and retry game; note that we may end up with more 1054 * conservative locks than required the second time around, so later 1055 * assertions have to accept that. Further analysis of the number of 1056 * misses under contention is required. 1057 * 1058 * XXXRW: Check that hash locking update here is correct. 1059 */ 1060 sin = (struct sockaddr_in *)addr; 1061 if (sin != NULL && 1062 (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) { 1063 INP_RUNLOCK(inp); 1064 INP_WLOCK(inp); 1065 INP_HASH_WLOCK(&V_udbinfo); 1066 unlock_udbinfo = UH_WLOCKED; 1067 } else if ((sin != NULL && ( 1068 (sin->sin_addr.s_addr == INADDR_ANY) || 1069 (sin->sin_addr.s_addr == INADDR_BROADCAST) || 1070 (inp->inp_laddr.s_addr == INADDR_ANY) || 1071 (inp->inp_lport == 0))) || 1072 (src.sin_family == AF_INET)) { 1073 INP_HASH_RLOCK(&V_udbinfo); 1074 unlock_udbinfo = UH_RLOCKED; 1075 } else 1076 unlock_udbinfo = UH_UNLOCKED; 1077 1078 /* 1079 * If the IP_SENDSRCADDR control message was specified, override the 1080 * source address for this datagram. Its use is invalidated if the 1081 * address thus specified is incomplete or clobbers other inpcbs. 1082 */ 1083 laddr = inp->inp_laddr; 1084 lport = inp->inp_lport; 1085 if (src.sin_family == AF_INET) { 1086 INP_HASH_LOCK_ASSERT(&V_udbinfo); 1087 if ((lport == 0) || 1088 (laddr.s_addr == INADDR_ANY && 1089 src.sin_addr.s_addr == INADDR_ANY)) { 1090 error = EINVAL; 1091 goto release; 1092 } 1093 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 1094 &laddr.s_addr, &lport, td->td_ucred); 1095 if (error) 1096 goto release; 1097 } 1098 1099 /* 1100 * If a UDP socket has been connected, then a local address/port will 1101 * have been selected and bound. 1102 * 1103 * If a UDP socket has not been connected to, then an explicit 1104 * destination address must be used, in which case a local 1105 * address/port may not have been selected and bound. 1106 */ 1107 if (sin != NULL) { 1108 INP_LOCK_ASSERT(inp); 1109 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1110 error = EISCONN; 1111 goto release; 1112 } 1113 1114 /* 1115 * Jail may rewrite the destination address, so let it do 1116 * that before we use it. 1117 */ 1118 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1119 if (error) 1120 goto release; 1121 1122 /* 1123 * If a local address or port hasn't yet been selected, or if 1124 * the destination address needs to be rewritten due to using 1125 * a special INADDR_ constant, invoke in_pcbconnect_setup() 1126 * to do the heavy lifting. Once a port is selected, we 1127 * commit the binding back to the socket; we also commit the 1128 * binding of the address if in jail. 1129 * 1130 * If we already have a valid binding and we're not 1131 * requesting a destination address rewrite, use a fast path. 1132 */ 1133 if (inp->inp_laddr.s_addr == INADDR_ANY || 1134 inp->inp_lport == 0 || 1135 sin->sin_addr.s_addr == INADDR_ANY || 1136 sin->sin_addr.s_addr == INADDR_BROADCAST) { 1137 INP_HASH_LOCK_ASSERT(&V_udbinfo); 1138 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, 1139 &lport, &faddr.s_addr, &fport, NULL, 1140 td->td_ucred); 1141 if (error) 1142 goto release; 1143 1144 /* 1145 * XXXRW: Why not commit the port if the address is 1146 * !INADDR_ANY? 1147 */ 1148 /* Commit the local port if newly assigned. */ 1149 if (inp->inp_laddr.s_addr == INADDR_ANY && 1150 inp->inp_lport == 0) { 1151 INP_WLOCK_ASSERT(inp); 1152 INP_HASH_WLOCK_ASSERT(&V_udbinfo); 1153 /* 1154 * Remember addr if jailed, to prevent 1155 * rebinding. 1156 */ 1157 if (prison_flag(td->td_ucred, PR_IP4)) 1158 inp->inp_laddr = laddr; 1159 inp->inp_lport = lport; 1160 if (in_pcbinshash(inp) != 0) { 1161 inp->inp_lport = 0; 1162 error = EAGAIN; 1163 goto release; 1164 } 1165 inp->inp_flags |= INP_ANONPORT; 1166 } 1167 } else { 1168 faddr = sin->sin_addr; 1169 fport = sin->sin_port; 1170 } 1171 } else { 1172 INP_LOCK_ASSERT(inp); 1173 faddr = inp->inp_faddr; 1174 fport = inp->inp_fport; 1175 if (faddr.s_addr == INADDR_ANY) { 1176 error = ENOTCONN; 1177 goto release; 1178 } 1179 } 1180 1181 /* 1182 * Calculate data length and get a mbuf for UDP, IP, and possible 1183 * link-layer headers. Immediate slide the data pointer back forward 1184 * since we won't use that space at this layer. 1185 */ 1186 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT); 1187 if (m == NULL) { 1188 error = ENOBUFS; 1189 goto release; 1190 } 1191 m->m_data += max_linkhdr; 1192 m->m_len -= max_linkhdr; 1193 m->m_pkthdr.len -= max_linkhdr; 1194 1195 /* 1196 * Fill in mbuf with extended UDP header and addresses and length put 1197 * into network format. 1198 */ 1199 ui = mtod(m, struct udpiphdr *); 1200 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 1201 ui->ui_v = IPVERSION << 4; 1202 ui->ui_pr = IPPROTO_UDP; 1203 ui->ui_src = laddr; 1204 ui->ui_dst = faddr; 1205 ui->ui_sport = lport; 1206 ui->ui_dport = fport; 1207 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 1208 1209 /* 1210 * Set the Don't Fragment bit in the IP header. 1211 */ 1212 if (inp->inp_flags & INP_DONTFRAG) { 1213 struct ip *ip; 1214 1215 ip = (struct ip *)&ui->ui_i; 1216 ip->ip_off |= htons(IP_DF); 1217 } 1218 1219 ipflags = 0; 1220 if (inp->inp_socket->so_options & SO_DONTROUTE) 1221 ipflags |= IP_ROUTETOIF; 1222 if (inp->inp_socket->so_options & SO_BROADCAST) 1223 ipflags |= IP_ALLOWBROADCAST; 1224 if (inp->inp_flags & INP_ONESBCAST) 1225 ipflags |= IP_SENDONES; 1226 1227 #ifdef MAC 1228 mac_inpcb_create_mbuf(inp, m); 1229 #endif 1230 1231 /* 1232 * Set up checksum and output datagram. 1233 */ 1234 if (V_udp_cksum) { 1235 if (inp->inp_flags & INP_ONESBCAST) 1236 faddr.s_addr = INADDR_BROADCAST; 1237 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 1238 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 1239 m->m_pkthdr.csum_flags = CSUM_UDP; 1240 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 1241 } else 1242 ui->ui_sum = 0; 1243 ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len); 1244 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 1245 ((struct ip *)ui)->ip_tos = tos; /* XXX */ 1246 UDPSTAT_INC(udps_opackets); 1247 1248 if (unlock_udbinfo == UH_WLOCKED) 1249 INP_HASH_WUNLOCK(&V_udbinfo); 1250 else if (unlock_udbinfo == UH_RLOCKED) 1251 INP_HASH_RUNLOCK(&V_udbinfo); 1252 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u); 1253 error = ip_output(m, inp->inp_options, NULL, ipflags, 1254 inp->inp_moptions, inp); 1255 if (unlock_udbinfo == UH_WLOCKED) 1256 INP_WUNLOCK(inp); 1257 else 1258 INP_RUNLOCK(inp); 1259 return (error); 1260 1261 release: 1262 if (unlock_udbinfo == UH_WLOCKED) { 1263 INP_HASH_WUNLOCK(&V_udbinfo); 1264 INP_WUNLOCK(inp); 1265 } else if (unlock_udbinfo == UH_RLOCKED) { 1266 INP_HASH_RUNLOCK(&V_udbinfo); 1267 INP_RUNLOCK(inp); 1268 } else 1269 INP_RUNLOCK(inp); 1270 m_freem(m); 1271 return (error); 1272 } 1273 1274 1275 #if defined(IPSEC) && defined(IPSEC_NAT_T) 1276 /* 1277 * Potentially decap ESP in UDP frame. Check for an ESP header 1278 * and optional marker; if present, strip the UDP header and 1279 * push the result through IPSec. 1280 * 1281 * Returns mbuf to be processed (potentially re-allocated) or 1282 * NULL if consumed and/or processed. 1283 */ 1284 static struct mbuf * 1285 udp4_espdecap(struct inpcb *inp, struct mbuf *m, int off) 1286 { 1287 size_t minlen, payload, skip, iphlen; 1288 caddr_t data; 1289 struct udpcb *up; 1290 struct m_tag *tag; 1291 struct udphdr *udphdr; 1292 struct ip *ip; 1293 1294 INP_RLOCK_ASSERT(inp); 1295 1296 /* 1297 * Pull up data so the longest case is contiguous: 1298 * IP/UDP hdr + non ESP marker + ESP hdr. 1299 */ 1300 minlen = off + sizeof(uint64_t) + sizeof(struct esp); 1301 if (minlen > m->m_pkthdr.len) 1302 minlen = m->m_pkthdr.len; 1303 if ((m = m_pullup(m, minlen)) == NULL) { 1304 IPSECSTAT_INC(ips_in_inval); 1305 return (NULL); /* Bypass caller processing. */ 1306 } 1307 data = mtod(m, caddr_t); /* Points to ip header. */ 1308 payload = m->m_len - off; /* Size of payload. */ 1309 1310 if (payload == 1 && data[off] == '\xff') 1311 return (m); /* NB: keepalive packet, no decap. */ 1312 1313 up = intoudpcb(inp); 1314 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 1315 KASSERT((up->u_flags & UF_ESPINUDP_ALL) != 0, 1316 ("u_flags 0x%x", up->u_flags)); 1317 1318 /* 1319 * Check that the payload is large enough to hold an 1320 * ESP header and compute the amount of data to remove. 1321 * 1322 * NB: the caller has already done a pullup for us. 1323 * XXX can we assume alignment and eliminate bcopys? 1324 */ 1325 if (up->u_flags & UF_ESPINUDP_NON_IKE) { 1326 /* 1327 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 1328 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, ignoring 1329 * possible AH mode non-IKE marker+non-ESP marker 1330 * from draft-ietf-ipsec-udp-encaps-00.txt. 1331 */ 1332 uint64_t marker; 1333 1334 if (payload <= sizeof(uint64_t) + sizeof(struct esp)) 1335 return (m); /* NB: no decap. */ 1336 bcopy(data + off, &marker, sizeof(uint64_t)); 1337 if (marker != 0) /* Non-IKE marker. */ 1338 return (m); /* NB: no decap. */ 1339 skip = sizeof(uint64_t) + sizeof(struct udphdr); 1340 } else { 1341 uint32_t spi; 1342 1343 if (payload <= sizeof(struct esp)) { 1344 IPSECSTAT_INC(ips_in_inval); 1345 m_freem(m); 1346 return (NULL); /* Discard. */ 1347 } 1348 bcopy(data + off, &spi, sizeof(uint32_t)); 1349 if (spi == 0) /* Non-ESP marker. */ 1350 return (m); /* NB: no decap. */ 1351 skip = sizeof(struct udphdr); 1352 } 1353 1354 /* 1355 * Setup a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember 1356 * the UDP ports. This is required if we want to select 1357 * the right SPD for multiple hosts behind same NAT. 1358 * 1359 * NB: ports are maintained in network byte order everywhere 1360 * in the NAT-T code. 1361 */ 1362 tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS, 1363 2 * sizeof(uint16_t), M_NOWAIT); 1364 if (tag == NULL) { 1365 IPSECSTAT_INC(ips_in_nomem); 1366 m_freem(m); 1367 return (NULL); /* Discard. */ 1368 } 1369 iphlen = off - sizeof(struct udphdr); 1370 udphdr = (struct udphdr *)(data + iphlen); 1371 ((uint16_t *)(tag + 1))[0] = udphdr->uh_sport; 1372 ((uint16_t *)(tag + 1))[1] = udphdr->uh_dport; 1373 m_tag_prepend(m, tag); 1374 1375 /* 1376 * Remove the UDP header (and possibly the non ESP marker) 1377 * IP header length is iphlen 1378 * Before: 1379 * <--- off ---> 1380 * +----+------+-----+ 1381 * | IP | UDP | ESP | 1382 * +----+------+-----+ 1383 * <-skip-> 1384 * After: 1385 * +----+-----+ 1386 * | IP | ESP | 1387 * +----+-----+ 1388 * <-skip-> 1389 */ 1390 ovbcopy(data, data + skip, iphlen); 1391 m_adj(m, skip); 1392 1393 ip = mtod(m, struct ip *); 1394 ip->ip_len = htons(ntohs(ip->ip_len) - skip); 1395 ip->ip_p = IPPROTO_ESP; 1396 1397 /* 1398 * We cannot yet update the cksums so clear any 1399 * h/w cksum flags as they are no longer valid. 1400 */ 1401 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) 1402 m->m_pkthdr.csum_flags &= ~(CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 1403 1404 (void) ipsec4_common_input(m, iphlen, ip->ip_p); 1405 return (NULL); /* NB: consumed, bypass processing. */ 1406 } 1407 #endif /* defined(IPSEC) && defined(IPSEC_NAT_T) */ 1408 1409 static void 1410 udp_abort(struct socket *so) 1411 { 1412 struct inpcb *inp; 1413 1414 inp = sotoinpcb(so); 1415 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 1416 INP_WLOCK(inp); 1417 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1418 INP_HASH_WLOCK(&V_udbinfo); 1419 in_pcbdisconnect(inp); 1420 inp->inp_laddr.s_addr = INADDR_ANY; 1421 INP_HASH_WUNLOCK(&V_udbinfo); 1422 soisdisconnected(so); 1423 } 1424 INP_WUNLOCK(inp); 1425 } 1426 1427 static int 1428 udp_attach(struct socket *so, int proto, struct thread *td) 1429 { 1430 struct inpcb *inp; 1431 int error; 1432 1433 inp = sotoinpcb(so); 1434 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 1435 error = soreserve(so, udp_sendspace, udp_recvspace); 1436 if (error) 1437 return (error); 1438 INP_INFO_WLOCK(&V_udbinfo); 1439 error = in_pcballoc(so, &V_udbinfo); 1440 if (error) { 1441 INP_INFO_WUNLOCK(&V_udbinfo); 1442 return (error); 1443 } 1444 1445 inp = sotoinpcb(so); 1446 inp->inp_vflag |= INP_IPV4; 1447 inp->inp_ip_ttl = V_ip_defttl; 1448 1449 error = udp_newudpcb(inp); 1450 if (error) { 1451 in_pcbdetach(inp); 1452 in_pcbfree(inp); 1453 INP_INFO_WUNLOCK(&V_udbinfo); 1454 return (error); 1455 } 1456 1457 INP_WUNLOCK(inp); 1458 INP_INFO_WUNLOCK(&V_udbinfo); 1459 return (0); 1460 } 1461 #endif /* INET */ 1462 1463 int 1464 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f) 1465 { 1466 struct inpcb *inp; 1467 struct udpcb *up; 1468 1469 KASSERT(so->so_type == SOCK_DGRAM, 1470 ("udp_set_kernel_tunneling: !dgram")); 1471 inp = sotoinpcb(so); 1472 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL")); 1473 INP_WLOCK(inp); 1474 up = intoudpcb(inp); 1475 if (up->u_tun_func != NULL) { 1476 INP_WUNLOCK(inp); 1477 return (EBUSY); 1478 } 1479 up->u_tun_func = f; 1480 INP_WUNLOCK(inp); 1481 return (0); 1482 } 1483 1484 #ifdef INET 1485 static int 1486 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1487 { 1488 struct inpcb *inp; 1489 int error; 1490 1491 inp = sotoinpcb(so); 1492 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1493 INP_WLOCK(inp); 1494 INP_HASH_WLOCK(&V_udbinfo); 1495 error = in_pcbbind(inp, nam, td->td_ucred); 1496 INP_HASH_WUNLOCK(&V_udbinfo); 1497 INP_WUNLOCK(inp); 1498 return (error); 1499 } 1500 1501 static void 1502 udp_close(struct socket *so) 1503 { 1504 struct inpcb *inp; 1505 1506 inp = sotoinpcb(so); 1507 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1508 INP_WLOCK(inp); 1509 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1510 INP_HASH_WLOCK(&V_udbinfo); 1511 in_pcbdisconnect(inp); 1512 inp->inp_laddr.s_addr = INADDR_ANY; 1513 INP_HASH_WUNLOCK(&V_udbinfo); 1514 soisdisconnected(so); 1515 } 1516 INP_WUNLOCK(inp); 1517 } 1518 1519 static int 1520 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1521 { 1522 struct inpcb *inp; 1523 int error; 1524 struct sockaddr_in *sin; 1525 1526 inp = sotoinpcb(so); 1527 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1528 INP_WLOCK(inp); 1529 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1530 INP_WUNLOCK(inp); 1531 return (EISCONN); 1532 } 1533 sin = (struct sockaddr_in *)nam; 1534 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1535 if (error != 0) { 1536 INP_WUNLOCK(inp); 1537 return (error); 1538 } 1539 INP_HASH_WLOCK(&V_udbinfo); 1540 error = in_pcbconnect(inp, nam, td->td_ucred); 1541 INP_HASH_WUNLOCK(&V_udbinfo); 1542 if (error == 0) 1543 soisconnected(so); 1544 INP_WUNLOCK(inp); 1545 return (error); 1546 } 1547 1548 static void 1549 udp_detach(struct socket *so) 1550 { 1551 struct inpcb *inp; 1552 struct udpcb *up; 1553 1554 inp = sotoinpcb(so); 1555 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1556 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY, 1557 ("udp_detach: not disconnected")); 1558 INP_INFO_WLOCK(&V_udbinfo); 1559 INP_WLOCK(inp); 1560 up = intoudpcb(inp); 1561 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 1562 inp->inp_ppcb = NULL; 1563 in_pcbdetach(inp); 1564 in_pcbfree(inp); 1565 INP_INFO_WUNLOCK(&V_udbinfo); 1566 udp_discardcb(up); 1567 } 1568 1569 static int 1570 udp_disconnect(struct socket *so) 1571 { 1572 struct inpcb *inp; 1573 1574 inp = sotoinpcb(so); 1575 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1576 INP_WLOCK(inp); 1577 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1578 INP_WUNLOCK(inp); 1579 return (ENOTCONN); 1580 } 1581 INP_HASH_WLOCK(&V_udbinfo); 1582 in_pcbdisconnect(inp); 1583 inp->inp_laddr.s_addr = INADDR_ANY; 1584 INP_HASH_WUNLOCK(&V_udbinfo); 1585 SOCK_LOCK(so); 1586 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1587 SOCK_UNLOCK(so); 1588 INP_WUNLOCK(inp); 1589 return (0); 1590 } 1591 1592 static int 1593 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1594 struct mbuf *control, struct thread *td) 1595 { 1596 struct inpcb *inp; 1597 1598 inp = sotoinpcb(so); 1599 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1600 return (udp_output(inp, m, addr, control, td)); 1601 } 1602 #endif /* INET */ 1603 1604 int 1605 udp_shutdown(struct socket *so) 1606 { 1607 struct inpcb *inp; 1608 1609 inp = sotoinpcb(so); 1610 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1611 INP_WLOCK(inp); 1612 socantsendmore(so); 1613 INP_WUNLOCK(inp); 1614 return (0); 1615 } 1616 1617 #ifdef INET 1618 struct pr_usrreqs udp_usrreqs = { 1619 .pru_abort = udp_abort, 1620 .pru_attach = udp_attach, 1621 .pru_bind = udp_bind, 1622 .pru_connect = udp_connect, 1623 .pru_control = in_control, 1624 .pru_detach = udp_detach, 1625 .pru_disconnect = udp_disconnect, 1626 .pru_peeraddr = in_getpeeraddr, 1627 .pru_send = udp_send, 1628 .pru_soreceive = soreceive_dgram, 1629 .pru_sosend = sosend_dgram, 1630 .pru_shutdown = udp_shutdown, 1631 .pru_sockaddr = in_getsockaddr, 1632 .pru_sosetlabel = in_pcbsosetlabel, 1633 .pru_close = udp_close, 1634 }; 1635 #endif /* INET */ 1636