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sys/netinet/udp_usrreq.c
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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: releng/9.1/sys/netinet/udp_usrreq.c 238240 2012-07-08 12:26:32Z bz $"); 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 int len; 342 struct ip save_ip; 343 struct sockaddr_in udp_in; 344 #ifdef IPFIREWALL_FORWARD 345 struct m_tag *fwd_tag; 346 #endif 347 348 ifp = m->m_pkthdr.rcvif; 349 UDPSTAT_INC(udps_ipackets); 350 351 /* 352 * Strip IP options, if any; should skip this, make available to 353 * user, and use on returned packets, but we don't yet have a way to 354 * check the checksum with options still present. 355 */ 356 if (iphlen > sizeof (struct ip)) { 357 ip_stripoptions(m, (struct mbuf *)0); 358 iphlen = sizeof(struct ip); 359 } 360 361 /* 362 * Get IP and UDP header together in first mbuf. 363 */ 364 ip = mtod(m, struct ip *); 365 if (m->m_len < iphlen + sizeof(struct udphdr)) { 366 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 367 UDPSTAT_INC(udps_hdrops); 368 return; 369 } 370 ip = mtod(m, struct ip *); 371 } 372 uh = (struct udphdr *)((caddr_t)ip + iphlen); 373 374 /* 375 * Destination port of 0 is illegal, based on RFC768. 376 */ 377 if (uh->uh_dport == 0) 378 goto badunlocked; 379 380 /* 381 * Construct sockaddr format source address. Stuff source address 382 * and datagram in user buffer. 383 */ 384 bzero(&udp_in, sizeof(udp_in)); 385 udp_in.sin_len = sizeof(udp_in); 386 udp_in.sin_family = AF_INET; 387 udp_in.sin_port = uh->uh_sport; 388 udp_in.sin_addr = ip->ip_src; 389 390 /* 391 * Make mbuf data length reflect UDP length. If not enough data to 392 * reflect UDP length, drop. 393 */ 394 len = ntohs((u_short)uh->uh_ulen); 395 if (ip->ip_len != len) { 396 if (len > ip->ip_len || len < sizeof(struct udphdr)) { 397 UDPSTAT_INC(udps_badlen); 398 goto badunlocked; 399 } 400 m_adj(m, len - ip->ip_len); 401 /* ip->ip_len = len; */ 402 } 403 404 /* 405 * Save a copy of the IP header in case we want restore it for 406 * sending an ICMP error message in response. 407 */ 408 if (!V_udp_blackhole) 409 save_ip = *ip; 410 else 411 memset(&save_ip, 0, sizeof(save_ip)); 412 413 /* 414 * Checksum extended UDP header and data. 415 */ 416 if (uh->uh_sum) { 417 u_short uh_sum; 418 419 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 420 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 421 uh_sum = m->m_pkthdr.csum_data; 422 else 423 uh_sum = in_pseudo(ip->ip_src.s_addr, 424 ip->ip_dst.s_addr, htonl((u_short)len + 425 m->m_pkthdr.csum_data + IPPROTO_UDP)); 426 uh_sum ^= 0xffff; 427 } else { 428 char b[9]; 429 430 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 431 bzero(((struct ipovly *)ip)->ih_x1, 9); 432 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 433 uh_sum = in_cksum(m, len + sizeof (struct ip)); 434 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 435 } 436 if (uh_sum) { 437 UDPSTAT_INC(udps_badsum); 438 m_freem(m); 439 return; 440 } 441 } else 442 UDPSTAT_INC(udps_nosum); 443 444 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 445 in_broadcast(ip->ip_dst, ifp)) { 446 struct inpcb *last; 447 struct ip_moptions *imo; 448 449 INP_INFO_RLOCK(&V_udbinfo); 450 last = NULL; 451 LIST_FOREACH(inp, &V_udb, inp_list) { 452 if (inp->inp_lport != uh->uh_dport) 453 continue; 454 #ifdef INET6 455 if ((inp->inp_vflag & INP_IPV4) == 0) 456 continue; 457 #endif 458 if (inp->inp_laddr.s_addr != INADDR_ANY && 459 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 460 continue; 461 if (inp->inp_faddr.s_addr != INADDR_ANY && 462 inp->inp_faddr.s_addr != ip->ip_src.s_addr) 463 continue; 464 if (inp->inp_fport != 0 && 465 inp->inp_fport != uh->uh_sport) 466 continue; 467 468 INP_RLOCK(inp); 469 470 /* 471 * XXXRW: Because we weren't holding either the inpcb 472 * or the hash lock when we checked for a match 473 * before, we should probably recheck now that the 474 * inpcb lock is held. 475 */ 476 477 /* 478 * Handle socket delivery policy for any-source 479 * and source-specific multicast. [RFC3678] 480 */ 481 imo = inp->inp_moptions; 482 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 483 struct sockaddr_in group; 484 int blocked; 485 if (imo == NULL) { 486 INP_RUNLOCK(inp); 487 continue; 488 } 489 bzero(&group, sizeof(struct sockaddr_in)); 490 group.sin_len = sizeof(struct sockaddr_in); 491 group.sin_family = AF_INET; 492 group.sin_addr = ip->ip_dst; 493 494 blocked = imo_multi_filter(imo, ifp, 495 (struct sockaddr *)&group, 496 (struct sockaddr *)&udp_in); 497 if (blocked != MCAST_PASS) { 498 if (blocked == MCAST_NOTGMEMBER) 499 IPSTAT_INC(ips_notmember); 500 if (blocked == MCAST_NOTSMEMBER || 501 blocked == MCAST_MUTED) 502 UDPSTAT_INC(udps_filtermcast); 503 INP_RUNLOCK(inp); 504 continue; 505 } 506 } 507 if (last != NULL) { 508 struct mbuf *n; 509 510 n = m_copy(m, 0, M_COPYALL); 511 udp_append(last, ip, n, iphlen, &udp_in); 512 INP_RUNLOCK(last); 513 } 514 last = inp; 515 /* 516 * Don't look for additional matches if this one does 517 * not have either the SO_REUSEPORT or SO_REUSEADDR 518 * socket options set. This heuristic avoids 519 * searching through all pcbs in the common case of a 520 * non-shared port. It assumes that an application 521 * will never clear these options after setting them. 522 */ 523 if ((last->inp_socket->so_options & 524 (SO_REUSEPORT|SO_REUSEADDR)) == 0) 525 break; 526 } 527 528 if (last == NULL) { 529 /* 530 * No matching pcb found; discard datagram. (No need 531 * to send an ICMP Port Unreachable for a broadcast 532 * or multicast datgram.) 533 */ 534 UDPSTAT_INC(udps_noportbcast); 535 if (inp) 536 INP_RUNLOCK(inp); 537 INP_INFO_RUNLOCK(&V_udbinfo); 538 goto badunlocked; 539 } 540 udp_append(last, ip, m, iphlen, &udp_in); 541 INP_RUNLOCK(last); 542 INP_INFO_RUNLOCK(&V_udbinfo); 543 return; 544 } 545 546 /* 547 * Locate pcb for datagram. 548 */ 549 #ifdef IPFIREWALL_FORWARD 550 /* 551 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. 552 */ 553 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 554 if (fwd_tag != NULL) { 555 struct sockaddr_in *next_hop; 556 557 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 558 559 /* 560 * Transparently forwarded. Pretend to be the destination. 561 * Already got one like this? 562 */ 563 inp = in_pcblookup_mbuf(&V_udbinfo, ip->ip_src, uh->uh_sport, 564 ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m); 565 if (!inp) { 566 /* 567 * It's new. Try to find the ambushing socket. 568 * Because we've rewritten the destination address, 569 * any hardware-generated hash is ignored. 570 */ 571 inp = in_pcblookup(&V_udbinfo, ip->ip_src, 572 uh->uh_sport, next_hop->sin_addr, 573 next_hop->sin_port ? htons(next_hop->sin_port) : 574 uh->uh_dport, INPLOOKUP_WILDCARD | 575 INPLOOKUP_RLOCKPCB, ifp); 576 } 577 /* Remove the tag from the packet. We don't need it anymore. */ 578 m_tag_delete(m, fwd_tag); 579 } else 580 #endif /* IPFIREWALL_FORWARD */ 581 inp = in_pcblookup_mbuf(&V_udbinfo, ip->ip_src, uh->uh_sport, 582 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD | 583 INPLOOKUP_RLOCKPCB, ifp, m); 584 if (inp == NULL) { 585 if (udp_log_in_vain) { 586 char buf[4*sizeof "123"]; 587 588 strcpy(buf, inet_ntoa(ip->ip_dst)); 589 log(LOG_INFO, 590 "Connection attempt to UDP %s:%d from %s:%d\n", 591 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 592 ntohs(uh->uh_sport)); 593 } 594 UDPSTAT_INC(udps_noport); 595 if (m->m_flags & (M_BCAST | M_MCAST)) { 596 UDPSTAT_INC(udps_noportbcast); 597 goto badunlocked; 598 } 599 if (V_udp_blackhole) 600 goto badunlocked; 601 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 602 goto badunlocked; 603 *ip = save_ip; 604 ip->ip_len += iphlen; 605 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 606 return; 607 } 608 609 /* 610 * Check the minimum TTL for socket. 611 */ 612 INP_RLOCK_ASSERT(inp); 613 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) { 614 INP_RUNLOCK(inp); 615 m_freem(m); 616 return; 617 } 618 udp_append(inp, ip, m, iphlen, &udp_in); 619 INP_RUNLOCK(inp); 620 return; 621 622 badunlocked: 623 m_freem(m); 624 } 625 #endif /* INET */ 626 627 /* 628 * Notify a udp user of an asynchronous error; just wake up so that they can 629 * collect error status. 630 */ 631 struct inpcb * 632 udp_notify(struct inpcb *inp, int errno) 633 { 634 635 /* 636 * While udp_ctlinput() always calls udp_notify() with a read lock 637 * when invoking it directly, in_pcbnotifyall() currently uses write 638 * locks due to sharing code with TCP. For now, accept either a read 639 * or a write lock, but a read lock is sufficient. 640 */ 641 INP_LOCK_ASSERT(inp); 642 643 inp->inp_socket->so_error = errno; 644 sorwakeup(inp->inp_socket); 645 sowwakeup(inp->inp_socket); 646 return (inp); 647 } 648 649 #ifdef INET 650 void 651 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 652 { 653 struct ip *ip = vip; 654 struct udphdr *uh; 655 struct in_addr faddr; 656 struct inpcb *inp; 657 658 faddr = ((struct sockaddr_in *)sa)->sin_addr; 659 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 660 return; 661 662 /* 663 * Redirects don't need to be handled up here. 664 */ 665 if (PRC_IS_REDIRECT(cmd)) 666 return; 667 668 /* 669 * Hostdead is ugly because it goes linearly through all PCBs. 670 * 671 * XXX: We never get this from ICMP, otherwise it makes an excellent 672 * DoS attack on machines with many connections. 673 */ 674 if (cmd == PRC_HOSTDEAD) 675 ip = NULL; 676 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 677 return; 678 if (ip != NULL) { 679 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 680 inp = in_pcblookup(&V_udbinfo, faddr, uh->uh_dport, 681 ip->ip_src, uh->uh_sport, INPLOOKUP_RLOCKPCB, NULL); 682 if (inp != NULL) { 683 INP_RLOCK_ASSERT(inp); 684 if (inp->inp_socket != NULL) { 685 udp_notify(inp, inetctlerrmap[cmd]); 686 } 687 INP_RUNLOCK(inp); 688 } 689 } else 690 in_pcbnotifyall(&V_udbinfo, faddr, inetctlerrmap[cmd], 691 udp_notify); 692 } 693 #endif /* INET */ 694 695 static int 696 udp_pcblist(SYSCTL_HANDLER_ARGS) 697 { 698 int error, i, n; 699 struct inpcb *inp, **inp_list; 700 inp_gen_t gencnt; 701 struct xinpgen xig; 702 703 /* 704 * The process of preparing the PCB list is too time-consuming and 705 * resource-intensive to repeat twice on every request. 706 */ 707 if (req->oldptr == 0) { 708 n = V_udbinfo.ipi_count; 709 n += imax(n / 8, 10); 710 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb); 711 return (0); 712 } 713 714 if (req->newptr != 0) 715 return (EPERM); 716 717 /* 718 * OK, now we're committed to doing something. 719 */ 720 INP_INFO_RLOCK(&V_udbinfo); 721 gencnt = V_udbinfo.ipi_gencnt; 722 n = V_udbinfo.ipi_count; 723 INP_INFO_RUNLOCK(&V_udbinfo); 724 725 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 726 + n * sizeof(struct xinpcb)); 727 if (error != 0) 728 return (error); 729 730 xig.xig_len = sizeof xig; 731 xig.xig_count = n; 732 xig.xig_gen = gencnt; 733 xig.xig_sogen = so_gencnt; 734 error = SYSCTL_OUT(req, &xig, sizeof xig); 735 if (error) 736 return (error); 737 738 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 739 if (inp_list == 0) 740 return (ENOMEM); 741 742 INP_INFO_RLOCK(&V_udbinfo); 743 for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n; 744 inp = LIST_NEXT(inp, inp_list)) { 745 INP_WLOCK(inp); 746 if (inp->inp_gencnt <= gencnt && 747 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 748 in_pcbref(inp); 749 inp_list[i++] = inp; 750 } 751 INP_WUNLOCK(inp); 752 } 753 INP_INFO_RUNLOCK(&V_udbinfo); 754 n = i; 755 756 error = 0; 757 for (i = 0; i < n; i++) { 758 inp = inp_list[i]; 759 INP_RLOCK(inp); 760 if (inp->inp_gencnt <= gencnt) { 761 struct xinpcb xi; 762 763 bzero(&xi, sizeof(xi)); 764 xi.xi_len = sizeof xi; 765 /* XXX should avoid extra copy */ 766 bcopy(inp, &xi.xi_inp, sizeof *inp); 767 if (inp->inp_socket) 768 sotoxsocket(inp->inp_socket, &xi.xi_socket); 769 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 770 INP_RUNLOCK(inp); 771 error = SYSCTL_OUT(req, &xi, sizeof xi); 772 } else 773 INP_RUNLOCK(inp); 774 } 775 INP_INFO_WLOCK(&V_udbinfo); 776 for (i = 0; i < n; i++) { 777 inp = inp_list[i]; 778 INP_RLOCK(inp); 779 if (!in_pcbrele_rlocked(inp)) 780 INP_RUNLOCK(inp); 781 } 782 INP_INFO_WUNLOCK(&V_udbinfo); 783 784 if (!error) { 785 /* 786 * Give the user an updated idea of our state. If the 787 * generation differs from what we told her before, she knows 788 * that something happened while we were processing this 789 * request, and it might be necessary to retry. 790 */ 791 INP_INFO_RLOCK(&V_udbinfo); 792 xig.xig_gen = V_udbinfo.ipi_gencnt; 793 xig.xig_sogen = so_gencnt; 794 xig.xig_count = V_udbinfo.ipi_count; 795 INP_INFO_RUNLOCK(&V_udbinfo); 796 error = SYSCTL_OUT(req, &xig, sizeof xig); 797 } 798 free(inp_list, M_TEMP); 799 return (error); 800 } 801 802 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, 803 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0, 804 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 805 806 #ifdef INET 807 static int 808 udp_getcred(SYSCTL_HANDLER_ARGS) 809 { 810 struct xucred xuc; 811 struct sockaddr_in addrs[2]; 812 struct inpcb *inp; 813 int error; 814 815 error = priv_check(req->td, PRIV_NETINET_GETCRED); 816 if (error) 817 return (error); 818 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 819 if (error) 820 return (error); 821 inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 822 addrs[0].sin_addr, addrs[0].sin_port, 823 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL); 824 if (inp != NULL) { 825 INP_RLOCK_ASSERT(inp); 826 if (inp->inp_socket == NULL) 827 error = ENOENT; 828 if (error == 0) 829 error = cr_canseeinpcb(req->td->td_ucred, inp); 830 if (error == 0) 831 cru2x(inp->inp_cred, &xuc); 832 INP_RUNLOCK(inp); 833 } else 834 error = ENOENT; 835 if (error == 0) 836 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 837 return (error); 838 } 839 840 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 841 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 842 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 843 #endif /* INET */ 844 845 int 846 udp_ctloutput(struct socket *so, struct sockopt *sopt) 847 { 848 int error = 0, optval; 849 struct inpcb *inp; 850 #ifdef IPSEC_NAT_T 851 struct udpcb *up; 852 #endif 853 854 inp = sotoinpcb(so); 855 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 856 INP_WLOCK(inp); 857 if (sopt->sopt_level != IPPROTO_UDP) { 858 #ifdef INET6 859 if (INP_CHECK_SOCKAF(so, AF_INET6)) { 860 INP_WUNLOCK(inp); 861 error = ip6_ctloutput(so, sopt); 862 } 863 #endif 864 #if defined(INET) && defined(INET6) 865 else 866 #endif 867 #ifdef INET 868 { 869 INP_WUNLOCK(inp); 870 error = ip_ctloutput(so, sopt); 871 } 872 #endif 873 return (error); 874 } 875 876 switch (sopt->sopt_dir) { 877 case SOPT_SET: 878 switch (sopt->sopt_name) { 879 case UDP_ENCAP: 880 INP_WUNLOCK(inp); 881 error = sooptcopyin(sopt, &optval, sizeof optval, 882 sizeof optval); 883 if (error) 884 break; 885 inp = sotoinpcb(so); 886 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 887 INP_WLOCK(inp); 888 #ifdef IPSEC_NAT_T 889 up = intoudpcb(inp); 890 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 891 #endif 892 switch (optval) { 893 case 0: 894 /* Clear all UDP encap. */ 895 #ifdef IPSEC_NAT_T 896 up->u_flags &= ~UF_ESPINUDP_ALL; 897 #endif 898 break; 899 #ifdef IPSEC_NAT_T 900 case UDP_ENCAP_ESPINUDP: 901 case UDP_ENCAP_ESPINUDP_NON_IKE: 902 up->u_flags &= ~UF_ESPINUDP_ALL; 903 if (optval == UDP_ENCAP_ESPINUDP) 904 up->u_flags |= UF_ESPINUDP; 905 else if (optval == UDP_ENCAP_ESPINUDP_NON_IKE) 906 up->u_flags |= UF_ESPINUDP_NON_IKE; 907 break; 908 #endif 909 default: 910 error = EINVAL; 911 break; 912 } 913 INP_WUNLOCK(inp); 914 break; 915 default: 916 INP_WUNLOCK(inp); 917 error = ENOPROTOOPT; 918 break; 919 } 920 break; 921 case SOPT_GET: 922 switch (sopt->sopt_name) { 923 #ifdef IPSEC_NAT_T 924 case UDP_ENCAP: 925 up = intoudpcb(inp); 926 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 927 optval = up->u_flags & UF_ESPINUDP_ALL; 928 INP_WUNLOCK(inp); 929 error = sooptcopyout(sopt, &optval, sizeof optval); 930 break; 931 #endif 932 default: 933 INP_WUNLOCK(inp); 934 error = ENOPROTOOPT; 935 break; 936 } 937 break; 938 } 939 return (error); 940 } 941 942 #ifdef INET 943 #define UH_WLOCKED 2 944 #define UH_RLOCKED 1 945 #define UH_UNLOCKED 0 946 static int 947 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr, 948 struct mbuf *control, struct thread *td) 949 { 950 struct udpiphdr *ui; 951 int len = m->m_pkthdr.len; 952 struct in_addr faddr, laddr; 953 struct cmsghdr *cm; 954 struct sockaddr_in *sin, src; 955 int error = 0; 956 int ipflags; 957 u_short fport, lport; 958 int unlock_udbinfo; 959 u_char tos; 960 961 /* 962 * udp_output() may need to temporarily bind or connect the current 963 * inpcb. As such, we don't know up front whether we will need the 964 * pcbinfo lock or not. Do any work to decide what is needed up 965 * front before acquiring any locks. 966 */ 967 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 968 if (control) 969 m_freem(control); 970 m_freem(m); 971 return (EMSGSIZE); 972 } 973 974 src.sin_family = 0; 975 INP_RLOCK(inp); 976 tos = inp->inp_ip_tos; 977 if (control != NULL) { 978 /* 979 * XXX: Currently, we assume all the optional information is 980 * stored in a single mbuf. 981 */ 982 if (control->m_next) { 983 INP_RUNLOCK(inp); 984 m_freem(control); 985 m_freem(m); 986 return (EINVAL); 987 } 988 for (; control->m_len > 0; 989 control->m_data += CMSG_ALIGN(cm->cmsg_len), 990 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 991 cm = mtod(control, struct cmsghdr *); 992 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 993 || cm->cmsg_len > control->m_len) { 994 error = EINVAL; 995 break; 996 } 997 if (cm->cmsg_level != IPPROTO_IP) 998 continue; 999 1000 switch (cm->cmsg_type) { 1001 case IP_SENDSRCADDR: 1002 if (cm->cmsg_len != 1003 CMSG_LEN(sizeof(struct in_addr))) { 1004 error = EINVAL; 1005 break; 1006 } 1007 bzero(&src, sizeof(src)); 1008 src.sin_family = AF_INET; 1009 src.sin_len = sizeof(src); 1010 src.sin_port = inp->inp_lport; 1011 src.sin_addr = 1012 *(struct in_addr *)CMSG_DATA(cm); 1013 break; 1014 1015 case IP_TOS: 1016 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) { 1017 error = EINVAL; 1018 break; 1019 } 1020 tos = *(u_char *)CMSG_DATA(cm); 1021 break; 1022 1023 default: 1024 error = ENOPROTOOPT; 1025 break; 1026 } 1027 if (error) 1028 break; 1029 } 1030 m_freem(control); 1031 } 1032 if (error) { 1033 INP_RUNLOCK(inp); 1034 m_freem(m); 1035 return (error); 1036 } 1037 1038 /* 1039 * Depending on whether or not the application has bound or connected 1040 * the socket, we may have to do varying levels of work. The optimal 1041 * case is for a connected UDP socket, as a global lock isn't 1042 * required at all. 1043 * 1044 * In order to decide which we need, we require stability of the 1045 * inpcb binding, which we ensure by acquiring a read lock on the 1046 * inpcb. This doesn't strictly follow the lock order, so we play 1047 * the trylock and retry game; note that we may end up with more 1048 * conservative locks than required the second time around, so later 1049 * assertions have to accept that. Further analysis of the number of 1050 * misses under contention is required. 1051 * 1052 * XXXRW: Check that hash locking update here is correct. 1053 */ 1054 sin = (struct sockaddr_in *)addr; 1055 if (sin != NULL && 1056 (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) { 1057 INP_RUNLOCK(inp); 1058 INP_WLOCK(inp); 1059 INP_HASH_WLOCK(&V_udbinfo); 1060 unlock_udbinfo = UH_WLOCKED; 1061 } else if ((sin != NULL && ( 1062 (sin->sin_addr.s_addr == INADDR_ANY) || 1063 (sin->sin_addr.s_addr == INADDR_BROADCAST) || 1064 (inp->inp_laddr.s_addr == INADDR_ANY) || 1065 (inp->inp_lport == 0))) || 1066 (src.sin_family == AF_INET)) { 1067 INP_HASH_RLOCK(&V_udbinfo); 1068 unlock_udbinfo = UH_RLOCKED; 1069 } else 1070 unlock_udbinfo = UH_UNLOCKED; 1071 1072 /* 1073 * If the IP_SENDSRCADDR control message was specified, override the 1074 * source address for this datagram. Its use is invalidated if the 1075 * address thus specified is incomplete or clobbers other inpcbs. 1076 */ 1077 laddr = inp->inp_laddr; 1078 lport = inp->inp_lport; 1079 if (src.sin_family == AF_INET) { 1080 INP_HASH_LOCK_ASSERT(&V_udbinfo); 1081 if ((lport == 0) || 1082 (laddr.s_addr == INADDR_ANY && 1083 src.sin_addr.s_addr == INADDR_ANY)) { 1084 error = EINVAL; 1085 goto release; 1086 } 1087 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 1088 &laddr.s_addr, &lport, td->td_ucred); 1089 if (error) 1090 goto release; 1091 } 1092 1093 /* 1094 * If a UDP socket has been connected, then a local address/port will 1095 * have been selected and bound. 1096 * 1097 * If a UDP socket has not been connected to, then an explicit 1098 * destination address must be used, in which case a local 1099 * address/port may not have been selected and bound. 1100 */ 1101 if (sin != NULL) { 1102 INP_LOCK_ASSERT(inp); 1103 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1104 error = EISCONN; 1105 goto release; 1106 } 1107 1108 /* 1109 * Jail may rewrite the destination address, so let it do 1110 * that before we use it. 1111 */ 1112 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1113 if (error) 1114 goto release; 1115 1116 /* 1117 * If a local address or port hasn't yet been selected, or if 1118 * the destination address needs to be rewritten due to using 1119 * a special INADDR_ constant, invoke in_pcbconnect_setup() 1120 * to do the heavy lifting. Once a port is selected, we 1121 * commit the binding back to the socket; we also commit the 1122 * binding of the address if in jail. 1123 * 1124 * If we already have a valid binding and we're not 1125 * requesting a destination address rewrite, use a fast path. 1126 */ 1127 if (inp->inp_laddr.s_addr == INADDR_ANY || 1128 inp->inp_lport == 0 || 1129 sin->sin_addr.s_addr == INADDR_ANY || 1130 sin->sin_addr.s_addr == INADDR_BROADCAST) { 1131 INP_HASH_LOCK_ASSERT(&V_udbinfo); 1132 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, 1133 &lport, &faddr.s_addr, &fport, NULL, 1134 td->td_ucred); 1135 if (error) 1136 goto release; 1137 1138 /* 1139 * XXXRW: Why not commit the port if the address is 1140 * !INADDR_ANY? 1141 */ 1142 /* Commit the local port if newly assigned. */ 1143 if (inp->inp_laddr.s_addr == INADDR_ANY && 1144 inp->inp_lport == 0) { 1145 INP_WLOCK_ASSERT(inp); 1146 INP_HASH_WLOCK_ASSERT(&V_udbinfo); 1147 /* 1148 * Remember addr if jailed, to prevent 1149 * rebinding. 1150 */ 1151 if (prison_flag(td->td_ucred, PR_IP4)) 1152 inp->inp_laddr = laddr; 1153 inp->inp_lport = lport; 1154 if (in_pcbinshash(inp) != 0) { 1155 inp->inp_lport = 0; 1156 error = EAGAIN; 1157 goto release; 1158 } 1159 inp->inp_flags |= INP_ANONPORT; 1160 } 1161 } else { 1162 faddr = sin->sin_addr; 1163 fport = sin->sin_port; 1164 } 1165 } else { 1166 INP_LOCK_ASSERT(inp); 1167 faddr = inp->inp_faddr; 1168 fport = inp->inp_fport; 1169 if (faddr.s_addr == INADDR_ANY) { 1170 error = ENOTCONN; 1171 goto release; 1172 } 1173 } 1174 1175 /* 1176 * Calculate data length and get a mbuf for UDP, IP, and possible 1177 * link-layer headers. Immediate slide the data pointer back forward 1178 * since we won't use that space at this layer. 1179 */ 1180 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT); 1181 if (m == NULL) { 1182 error = ENOBUFS; 1183 goto release; 1184 } 1185 m->m_data += max_linkhdr; 1186 m->m_len -= max_linkhdr; 1187 m->m_pkthdr.len -= max_linkhdr; 1188 1189 /* 1190 * Fill in mbuf with extended UDP header and addresses and length put 1191 * into network format. 1192 */ 1193 ui = mtod(m, struct udpiphdr *); 1194 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 1195 ui->ui_pr = IPPROTO_UDP; 1196 ui->ui_src = laddr; 1197 ui->ui_dst = faddr; 1198 ui->ui_sport = lport; 1199 ui->ui_dport = fport; 1200 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 1201 1202 /* 1203 * Set the Don't Fragment bit in the IP header. 1204 */ 1205 if (inp->inp_flags & INP_DONTFRAG) { 1206 struct ip *ip; 1207 1208 ip = (struct ip *)&ui->ui_i; 1209 ip->ip_off |= IP_DF; 1210 } 1211 1212 ipflags = 0; 1213 if (inp->inp_socket->so_options & SO_DONTROUTE) 1214 ipflags |= IP_ROUTETOIF; 1215 if (inp->inp_socket->so_options & SO_BROADCAST) 1216 ipflags |= IP_ALLOWBROADCAST; 1217 if (inp->inp_flags & INP_ONESBCAST) 1218 ipflags |= IP_SENDONES; 1219 1220 #ifdef MAC 1221 mac_inpcb_create_mbuf(inp, m); 1222 #endif 1223 1224 /* 1225 * Set up checksum and output datagram. 1226 */ 1227 if (V_udp_cksum) { 1228 if (inp->inp_flags & INP_ONESBCAST) 1229 faddr.s_addr = INADDR_BROADCAST; 1230 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 1231 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 1232 m->m_pkthdr.csum_flags = CSUM_UDP; 1233 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 1234 } else 1235 ui->ui_sum = 0; 1236 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 1237 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 1238 ((struct ip *)ui)->ip_tos = tos; /* XXX */ 1239 UDPSTAT_INC(udps_opackets); 1240 1241 if (unlock_udbinfo == UH_WLOCKED) 1242 INP_HASH_WUNLOCK(&V_udbinfo); 1243 else if (unlock_udbinfo == UH_RLOCKED) 1244 INP_HASH_RUNLOCK(&V_udbinfo); 1245 error = ip_output(m, inp->inp_options, NULL, ipflags, 1246 inp->inp_moptions, inp); 1247 if (unlock_udbinfo == UH_WLOCKED) 1248 INP_WUNLOCK(inp); 1249 else 1250 INP_RUNLOCK(inp); 1251 return (error); 1252 1253 release: 1254 if (unlock_udbinfo == UH_WLOCKED) { 1255 INP_HASH_WUNLOCK(&V_udbinfo); 1256 INP_WUNLOCK(inp); 1257 } else if (unlock_udbinfo == UH_RLOCKED) { 1258 INP_HASH_RUNLOCK(&V_udbinfo); 1259 INP_RUNLOCK(inp); 1260 } else 1261 INP_RUNLOCK(inp); 1262 m_freem(m); 1263 return (error); 1264 } 1265 1266 1267 #if defined(IPSEC) && defined(IPSEC_NAT_T) 1268 /* 1269 * Potentially decap ESP in UDP frame. Check for an ESP header 1270 * and optional marker; if present, strip the UDP header and 1271 * push the result through IPSec. 1272 * 1273 * Returns mbuf to be processed (potentially re-allocated) or 1274 * NULL if consumed and/or processed. 1275 */ 1276 static struct mbuf * 1277 udp4_espdecap(struct inpcb *inp, struct mbuf *m, int off) 1278 { 1279 size_t minlen, payload, skip, iphlen; 1280 caddr_t data; 1281 struct udpcb *up; 1282 struct m_tag *tag; 1283 struct udphdr *udphdr; 1284 struct ip *ip; 1285 1286 INP_RLOCK_ASSERT(inp); 1287 1288 /* 1289 * Pull up data so the longest case is contiguous: 1290 * IP/UDP hdr + non ESP marker + ESP hdr. 1291 */ 1292 minlen = off + sizeof(uint64_t) + sizeof(struct esp); 1293 if (minlen > m->m_pkthdr.len) 1294 minlen = m->m_pkthdr.len; 1295 if ((m = m_pullup(m, minlen)) == NULL) { 1296 V_ipsec4stat.in_inval++; 1297 return (NULL); /* Bypass caller processing. */ 1298 } 1299 data = mtod(m, caddr_t); /* Points to ip header. */ 1300 payload = m->m_len - off; /* Size of payload. */ 1301 1302 if (payload == 1 && data[off] == '\xff') 1303 return (m); /* NB: keepalive packet, no decap. */ 1304 1305 up = intoudpcb(inp); 1306 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 1307 KASSERT((up->u_flags & UF_ESPINUDP_ALL) != 0, 1308 ("u_flags 0x%x", up->u_flags)); 1309 1310 /* 1311 * Check that the payload is large enough to hold an 1312 * ESP header and compute the amount of data to remove. 1313 * 1314 * NB: the caller has already done a pullup for us. 1315 * XXX can we assume alignment and eliminate bcopys? 1316 */ 1317 if (up->u_flags & UF_ESPINUDP_NON_IKE) { 1318 /* 1319 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 1320 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, ignoring 1321 * possible AH mode non-IKE marker+non-ESP marker 1322 * from draft-ietf-ipsec-udp-encaps-00.txt. 1323 */ 1324 uint64_t marker; 1325 1326 if (payload <= sizeof(uint64_t) + sizeof(struct esp)) 1327 return (m); /* NB: no decap. */ 1328 bcopy(data + off, &marker, sizeof(uint64_t)); 1329 if (marker != 0) /* Non-IKE marker. */ 1330 return (m); /* NB: no decap. */ 1331 skip = sizeof(uint64_t) + sizeof(struct udphdr); 1332 } else { 1333 uint32_t spi; 1334 1335 if (payload <= sizeof(struct esp)) { 1336 V_ipsec4stat.in_inval++; 1337 m_freem(m); 1338 return (NULL); /* Discard. */ 1339 } 1340 bcopy(data + off, &spi, sizeof(uint32_t)); 1341 if (spi == 0) /* Non-ESP marker. */ 1342 return (m); /* NB: no decap. */ 1343 skip = sizeof(struct udphdr); 1344 } 1345 1346 /* 1347 * Setup a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember 1348 * the UDP ports. This is required if we want to select 1349 * the right SPD for multiple hosts behind same NAT. 1350 * 1351 * NB: ports are maintained in network byte order everywhere 1352 * in the NAT-T code. 1353 */ 1354 tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS, 1355 2 * sizeof(uint16_t), M_NOWAIT); 1356 if (tag == NULL) { 1357 V_ipsec4stat.in_nomem++; 1358 m_freem(m); 1359 return (NULL); /* Discard. */ 1360 } 1361 iphlen = off - sizeof(struct udphdr); 1362 udphdr = (struct udphdr *)(data + iphlen); 1363 ((uint16_t *)(tag + 1))[0] = udphdr->uh_sport; 1364 ((uint16_t *)(tag + 1))[1] = udphdr->uh_dport; 1365 m_tag_prepend(m, tag); 1366 1367 /* 1368 * Remove the UDP header (and possibly the non ESP marker) 1369 * IP header length is iphlen 1370 * Before: 1371 * <--- off ---> 1372 * +----+------+-----+ 1373 * | IP | UDP | ESP | 1374 * +----+------+-----+ 1375 * <-skip-> 1376 * After: 1377 * +----+-----+ 1378 * | IP | ESP | 1379 * +----+-----+ 1380 * <-skip-> 1381 */ 1382 ovbcopy(data, data + skip, iphlen); 1383 m_adj(m, skip); 1384 1385 ip = mtod(m, struct ip *); 1386 ip->ip_len -= skip; 1387 ip->ip_p = IPPROTO_ESP; 1388 1389 /* 1390 * We cannot yet update the cksums so clear any 1391 * h/w cksum flags as they are no longer valid. 1392 */ 1393 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) 1394 m->m_pkthdr.csum_flags &= ~(CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 1395 1396 (void) ipsec4_common_input(m, iphlen, ip->ip_p); 1397 return (NULL); /* NB: consumed, bypass processing. */ 1398 } 1399 #endif /* defined(IPSEC) && defined(IPSEC_NAT_T) */ 1400 1401 static void 1402 udp_abort(struct socket *so) 1403 { 1404 struct inpcb *inp; 1405 1406 inp = sotoinpcb(so); 1407 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 1408 INP_WLOCK(inp); 1409 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1410 INP_HASH_WLOCK(&V_udbinfo); 1411 in_pcbdisconnect(inp); 1412 inp->inp_laddr.s_addr = INADDR_ANY; 1413 INP_HASH_WUNLOCK(&V_udbinfo); 1414 soisdisconnected(so); 1415 } 1416 INP_WUNLOCK(inp); 1417 } 1418 1419 static int 1420 udp_attach(struct socket *so, int proto, struct thread *td) 1421 { 1422 struct inpcb *inp; 1423 int error; 1424 1425 inp = sotoinpcb(so); 1426 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 1427 error = soreserve(so, udp_sendspace, udp_recvspace); 1428 if (error) 1429 return (error); 1430 INP_INFO_WLOCK(&V_udbinfo); 1431 error = in_pcballoc(so, &V_udbinfo); 1432 if (error) { 1433 INP_INFO_WUNLOCK(&V_udbinfo); 1434 return (error); 1435 } 1436 1437 inp = sotoinpcb(so); 1438 inp->inp_vflag |= INP_IPV4; 1439 inp->inp_ip_ttl = V_ip_defttl; 1440 1441 error = udp_newudpcb(inp); 1442 if (error) { 1443 in_pcbdetach(inp); 1444 in_pcbfree(inp); 1445 INP_INFO_WUNLOCK(&V_udbinfo); 1446 return (error); 1447 } 1448 1449 INP_WUNLOCK(inp); 1450 INP_INFO_WUNLOCK(&V_udbinfo); 1451 return (0); 1452 } 1453 #endif /* INET */ 1454 1455 int 1456 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f) 1457 { 1458 struct inpcb *inp; 1459 struct udpcb *up; 1460 1461 KASSERT(so->so_type == SOCK_DGRAM, 1462 ("udp_set_kernel_tunneling: !dgram")); 1463 inp = sotoinpcb(so); 1464 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL")); 1465 INP_WLOCK(inp); 1466 up = intoudpcb(inp); 1467 if (up->u_tun_func != NULL) { 1468 INP_WUNLOCK(inp); 1469 return (EBUSY); 1470 } 1471 up->u_tun_func = f; 1472 INP_WUNLOCK(inp); 1473 return (0); 1474 } 1475 1476 #ifdef INET 1477 static int 1478 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1479 { 1480 struct inpcb *inp; 1481 int error; 1482 1483 inp = sotoinpcb(so); 1484 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1485 INP_WLOCK(inp); 1486 INP_HASH_WLOCK(&V_udbinfo); 1487 error = in_pcbbind(inp, nam, td->td_ucred); 1488 INP_HASH_WUNLOCK(&V_udbinfo); 1489 INP_WUNLOCK(inp); 1490 return (error); 1491 } 1492 1493 static void 1494 udp_close(struct socket *so) 1495 { 1496 struct inpcb *inp; 1497 1498 inp = sotoinpcb(so); 1499 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1500 INP_WLOCK(inp); 1501 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1502 INP_HASH_WLOCK(&V_udbinfo); 1503 in_pcbdisconnect(inp); 1504 inp->inp_laddr.s_addr = INADDR_ANY; 1505 INP_HASH_WUNLOCK(&V_udbinfo); 1506 soisdisconnected(so); 1507 } 1508 INP_WUNLOCK(inp); 1509 } 1510 1511 static int 1512 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1513 { 1514 struct inpcb *inp; 1515 int error; 1516 struct sockaddr_in *sin; 1517 1518 inp = sotoinpcb(so); 1519 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1520 INP_WLOCK(inp); 1521 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1522 INP_WUNLOCK(inp); 1523 return (EISCONN); 1524 } 1525 sin = (struct sockaddr_in *)nam; 1526 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1527 if (error != 0) { 1528 INP_WUNLOCK(inp); 1529 return (error); 1530 } 1531 INP_HASH_WLOCK(&V_udbinfo); 1532 error = in_pcbconnect(inp, nam, td->td_ucred); 1533 INP_HASH_WUNLOCK(&V_udbinfo); 1534 if (error == 0) 1535 soisconnected(so); 1536 INP_WUNLOCK(inp); 1537 return (error); 1538 } 1539 1540 static void 1541 udp_detach(struct socket *so) 1542 { 1543 struct inpcb *inp; 1544 struct udpcb *up; 1545 1546 inp = sotoinpcb(so); 1547 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1548 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY, 1549 ("udp_detach: not disconnected")); 1550 INP_INFO_WLOCK(&V_udbinfo); 1551 INP_WLOCK(inp); 1552 up = intoudpcb(inp); 1553 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 1554 inp->inp_ppcb = NULL; 1555 in_pcbdetach(inp); 1556 in_pcbfree(inp); 1557 INP_INFO_WUNLOCK(&V_udbinfo); 1558 udp_discardcb(up); 1559 } 1560 1561 static int 1562 udp_disconnect(struct socket *so) 1563 { 1564 struct inpcb *inp; 1565 1566 inp = sotoinpcb(so); 1567 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1568 INP_WLOCK(inp); 1569 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1570 INP_WUNLOCK(inp); 1571 return (ENOTCONN); 1572 } 1573 INP_HASH_WLOCK(&V_udbinfo); 1574 in_pcbdisconnect(inp); 1575 inp->inp_laddr.s_addr = INADDR_ANY; 1576 INP_HASH_WUNLOCK(&V_udbinfo); 1577 SOCK_LOCK(so); 1578 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1579 SOCK_UNLOCK(so); 1580 INP_WUNLOCK(inp); 1581 return (0); 1582 } 1583 1584 static int 1585 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1586 struct mbuf *control, struct thread *td) 1587 { 1588 struct inpcb *inp; 1589 1590 inp = sotoinpcb(so); 1591 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1592 return (udp_output(inp, m, addr, control, td)); 1593 } 1594 #endif /* INET */ 1595 1596 int 1597 udp_shutdown(struct socket *so) 1598 { 1599 struct inpcb *inp; 1600 1601 inp = sotoinpcb(so); 1602 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1603 INP_WLOCK(inp); 1604 socantsendmore(so); 1605 INP_WUNLOCK(inp); 1606 return (0); 1607 } 1608 1609 #ifdef INET 1610 struct pr_usrreqs udp_usrreqs = { 1611 .pru_abort = udp_abort, 1612 .pru_attach = udp_attach, 1613 .pru_bind = udp_bind, 1614 .pru_connect = udp_connect, 1615 .pru_control = in_control, 1616 .pru_detach = udp_detach, 1617 .pru_disconnect = udp_disconnect, 1618 .pru_peeraddr = in_getpeeraddr, 1619 .pru_send = udp_send, 1620 .pru_soreceive = soreceive_dgram, 1621 .pru_sosend = sosend_dgram, 1622 .pru_shutdown = udp_shutdown, 1623 .pru_sockaddr = in_getsockaddr, 1624 .pru_sosetlabel = in_pcbsosetlabel, 1625 .pru_close = udp_close, 1626 }; 1627 #endif /* INET */
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