1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 3 * The Regents of the University of California. 4 * Copyright (c) 2008 Robert N. M. Watson 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 4. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_ipfw.h" 38 #include "opt_inet6.h" 39 #include "opt_ipsec.h" 40 41 #include <sys/param.h> 42 #include <sys/domain.h> 43 #include <sys/eventhandler.h> 44 #include <sys/jail.h> 45 #include <sys/kernel.h> 46 #include <sys/lock.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #include <sys/priv.h> 50 #include <sys/proc.h> 51 #include <sys/protosw.h> 52 #include <sys/signalvar.h> 53 #include <sys/socket.h> 54 #include <sys/socketvar.h> 55 #include <sys/sx.h> 56 #include <sys/sysctl.h> 57 #include <sys/syslog.h> 58 #include <sys/systm.h> 59 60 #include <vm/uma.h> 61 62 #include <net/if.h> 63 #include <net/route.h> 64 65 #include <netinet/in.h> 66 #include <netinet/in_pcb.h> 67 #include <netinet/in_systm.h> 68 #include <netinet/in_var.h> 69 #include <netinet/ip.h> 70 #ifdef INET6 71 #include <netinet/ip6.h> 72 #endif 73 #include <netinet/ip_icmp.h> 74 #include <netinet/icmp_var.h> 75 #include <netinet/ip_var.h> 76 #include <netinet/ip_options.h> 77 #ifdef INET6 78 #include <netinet6/ip6_var.h> 79 #endif 80 #include <netinet/udp.h> 81 #include <netinet/udp_var.h> 82 83 #ifdef IPSEC 84 #include <netipsec/ipsec.h> 85 #include <netipsec/esp.h> 86 #endif 87 88 #include <machine/in_cksum.h> 89 90 #include <security/mac/mac_framework.h> 91 92 /* 93 * UDP protocol implementation. 94 * Per RFC 768, August, 1980. 95 */ 96 97 VNET_DEFINE(int, udp_blackhole); 98 99 /* 100 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums 101 * removes the only data integrity mechanism for packets and malformed 102 * packets that would otherwise be discarded due to bad checksums, and may 103 * cause problems (especially for NFS data blocks). 104 */ 105 static int udp_cksum = 1; 106 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, &udp_cksum, 107 0, "compute udp checksum"); 108 109 int udp_log_in_vain = 0; 110 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW, 111 &udp_log_in_vain, 0, "Log all incoming UDP packets"); 112 113 SYSCTL_VNET_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW, 114 &VNET_NAME(udp_blackhole), 0, 115 "Do not send port unreachables for refused connects"); 116 117 u_long udp_sendspace = 9216; /* really max datagram size */ 118 /* 40 1K datagrams */ 119 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 120 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 121 122 u_long udp_recvspace = 40 * (1024 + 123 #ifdef INET6 124 sizeof(struct sockaddr_in6) 125 #else 126 sizeof(struct sockaddr_in) 127 #endif 128 ); 129 130 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 131 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 132 133 VNET_DEFINE(struct inpcbhead, udb); /* from udp_var.h */ 134 VNET_DEFINE(struct inpcbinfo, udbinfo); 135 static VNET_DEFINE(uma_zone_t, udpcb_zone); 136 VNET_DEFINE(struct udpstat, udpstat); /* from udp_var.h */ 137 138 #define V_udpcb_zone VNET(udpcb_zone) 139 140 #ifndef UDBHASHSIZE 141 #define UDBHASHSIZE 128 142 #endif 143 144 SYSCTL_VNET_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW, 145 &VNET_NAME(udpstat), udpstat, 146 "UDP statistics (struct udpstat, netinet/udp_var.h)"); 147 148 static void udp_detach(struct socket *so); 149 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 150 struct mbuf *, struct thread *); 151 #ifdef IPSEC 152 #ifdef IPSEC_NAT_T 153 #define UF_ESPINUDP_ALL (UF_ESPINUDP_NON_IKE|UF_ESPINUDP) 154 #ifdef INET 155 static struct mbuf *udp4_espdecap(struct inpcb *, struct mbuf *, int); 156 #endif 157 #endif /* IPSEC_NAT_T */ 158 #endif /* IPSEC */ 159 160 static void 161 udp_zone_change(void *tag) 162 { 163 164 uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets); 165 uma_zone_set_max(V_udpcb_zone, maxsockets); 166 } 167 168 static int 169 udp_inpcb_init(void *mem, int size, int flags) 170 { 171 struct inpcb *inp; 172 173 inp = mem; 174 INP_LOCK_INIT(inp, "inp", "udpinp"); 175 return (0); 176 } 177 178 void 179 udp_init(void) 180 { 181 182 V_udp_blackhole = 0; 183 184 INP_INFO_LOCK_INIT(&V_udbinfo, "udp"); 185 LIST_INIT(&V_udb); 186 #ifdef VIMAGE 187 V_udbinfo.ipi_vnet = curvnet; 188 #endif 189 V_udbinfo.ipi_listhead = &V_udb; 190 V_udbinfo.ipi_hashbase = hashinit(UDBHASHSIZE, M_PCB, 191 &V_udbinfo.ipi_hashmask); 192 V_udbinfo.ipi_porthashbase = hashinit(UDBHASHSIZE, M_PCB, 193 &V_udbinfo.ipi_porthashmask); 194 V_udbinfo.ipi_zone = uma_zcreate("udp_inpcb", sizeof(struct inpcb), 195 NULL, NULL, udp_inpcb_init, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 196 uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets); 197 198 V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb), 199 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 200 uma_zone_set_max(V_udpcb_zone, maxsockets); 201 202 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL, 203 EVENTHANDLER_PRI_ANY); 204 } 205 206 /* 207 * Kernel module interface for updating udpstat. The argument is an index 208 * into udpstat treated as an array of u_long. While this encodes the 209 * general layout of udpstat into the caller, it doesn't encode its location, 210 * so that future changes to add, for example, per-CPU stats support won't 211 * cause binary compatibility problems for kernel modules. 212 */ 213 void 214 kmod_udpstat_inc(int statnum) 215 { 216 217 (*((u_long *)&V_udpstat + statnum))++; 218 } 219 220 int 221 udp_newudpcb(struct inpcb *inp) 222 { 223 struct udpcb *up; 224 225 up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO); 226 if (up == NULL) 227 return (ENOBUFS); 228 inp->inp_ppcb = up; 229 return (0); 230 } 231 232 void 233 udp_discardcb(struct udpcb *up) 234 { 235 236 uma_zfree(V_udpcb_zone, up); 237 } 238 239 #ifdef VIMAGE 240 void 241 udp_destroy(void) 242 { 243 244 hashdestroy(V_udbinfo.ipi_hashbase, M_PCB, 245 V_udbinfo.ipi_hashmask); 246 hashdestroy(V_udbinfo.ipi_porthashbase, M_PCB, 247 V_udbinfo.ipi_porthashmask); 248 INP_INFO_LOCK_DESTROY(&V_udbinfo); 249 } 250 #endif 251 252 /* 253 * Subroutine of udp_input(), which appends the provided mbuf chain to the 254 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 255 * contains the source address. If the socket ends up being an IPv6 socket, 256 * udp_append() will convert to a sockaddr_in6 before passing the address 257 * into the socket code. 258 */ 259 static void 260 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off, 261 struct sockaddr_in *udp_in) 262 { 263 struct sockaddr *append_sa; 264 struct socket *so; 265 struct mbuf *opts = 0; 266 #ifdef INET6 267 struct sockaddr_in6 udp_in6; 268 #endif 269 #ifdef IPSEC 270 #ifdef IPSEC_NAT_T 271 #ifdef INET 272 struct udpcb *up; 273 #endif 274 #endif 275 #endif 276 277 INP_RLOCK_ASSERT(inp); 278 279 #ifdef IPSEC 280 /* Check AH/ESP integrity. */ 281 if (ipsec4_in_reject(n, inp)) { 282 m_freem(n); 283 V_ipsec4stat.in_polvio++; 284 return; 285 } 286 #ifdef IPSEC_NAT_T 287 #ifdef INET 288 up = intoudpcb(inp); 289 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 290 if (up->u_flags & UF_ESPINUDP_ALL) { /* IPSec UDP encaps. */ 291 n = udp4_espdecap(inp, n, off); 292 if (n == NULL) /* Consumed. */ 293 return; 294 } 295 #endif /* INET */ 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 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 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 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 struct udpcb *up; 346 int len; 347 struct ip save_ip; 348 struct sockaddr_in udp_in; 349 #ifdef IPFIREWALL_FORWARD 350 struct m_tag *fwd_tag; 351 #endif 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, (struct mbuf *)0); 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 if (ip->ip_len != len) { 401 if (len > ip->ip_len || len < sizeof(struct udphdr)) { 402 UDPSTAT_INC(udps_badlen); 403 goto badunlocked; 404 } 405 m_adj(m, len - ip->ip_len); 406 /* ip->ip_len = 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 #ifdef IPFIREWALL_FORWARD 450 /* 451 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. 452 */ 453 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 454 if (fwd_tag != NULL) { 455 struct sockaddr_in *next_hop; 456 457 /* 458 * Do the hack. 459 */ 460 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 461 ip->ip_dst = next_hop->sin_addr; 462 uh->uh_dport = ntohs(next_hop->sin_port); 463 464 /* 465 * Remove the tag from the packet. We don't need it anymore. 466 */ 467 m_tag_delete(m, fwd_tag); 468 } 469 #endif 470 471 INP_INFO_RLOCK(&V_udbinfo); 472 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 473 in_broadcast(ip->ip_dst, ifp)) { 474 struct inpcb *last; 475 struct ip_moptions *imo; 476 477 last = NULL; 478 LIST_FOREACH(inp, &V_udb, inp_list) { 479 if (inp->inp_lport != uh->uh_dport) 480 continue; 481 #ifdef INET6 482 if ((inp->inp_vflag & INP_IPV4) == 0) 483 continue; 484 #endif 485 if (inp->inp_laddr.s_addr != INADDR_ANY && 486 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 487 continue; 488 if (inp->inp_faddr.s_addr != INADDR_ANY && 489 inp->inp_faddr.s_addr != ip->ip_src.s_addr) 490 continue; 491 if (inp->inp_fport != 0 && 492 inp->inp_fport != uh->uh_sport) 493 continue; 494 495 INP_RLOCK(inp); 496 497 /* 498 * Handle socket delivery policy for any-source 499 * and source-specific multicast. [RFC3678] 500 */ 501 imo = inp->inp_moptions; 502 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) && 503 imo != NULL) { 504 struct sockaddr_in group; 505 int blocked; 506 507 bzero(&group, sizeof(struct sockaddr_in)); 508 group.sin_len = sizeof(struct sockaddr_in); 509 group.sin_family = AF_INET; 510 group.sin_addr = ip->ip_dst; 511 512 blocked = imo_multi_filter(imo, ifp, 513 (struct sockaddr *)&group, 514 (struct sockaddr *)&udp_in); 515 if (blocked != MCAST_PASS) { 516 if (blocked == MCAST_NOTGMEMBER) 517 IPSTAT_INC(ips_notmember); 518 if (blocked == MCAST_NOTSMEMBER || 519 blocked == MCAST_MUTED) 520 UDPSTAT_INC(udps_filtermcast); 521 INP_RUNLOCK(inp); 522 continue; 523 } 524 } 525 if (last != NULL) { 526 struct mbuf *n; 527 528 n = m_copy(m, 0, M_COPYALL); 529 up = intoudpcb(last); 530 if (up->u_tun_func == NULL) { 531 if (n != NULL) 532 udp_append(last, 533 ip, n, 534 iphlen + 535 sizeof(struct udphdr), 536 &udp_in); 537 } else { 538 /* 539 * Engage the tunneling protocol we 540 * will have to leave the info_lock 541 * up, since we are hunting through 542 * multiple UDP's. 543 */ 544 545 (*up->u_tun_func)(n, iphlen, last); 546 } 547 INP_RUNLOCK(last); 548 } 549 last = inp; 550 /* 551 * Don't look for additional matches if this one does 552 * not have either the SO_REUSEPORT or SO_REUSEADDR 553 * socket options set. This heuristic avoids 554 * searching through all pcbs in the common case of a 555 * non-shared port. It assumes that an application 556 * will never clear these options after setting them. 557 */ 558 if ((last->inp_socket->so_options & 559 (SO_REUSEPORT|SO_REUSEADDR)) == 0) 560 break; 561 } 562 563 if (last == NULL) { 564 /* 565 * No matching pcb found; discard datagram. (No need 566 * to send an ICMP Port Unreachable for a broadcast 567 * or multicast datgram.) 568 */ 569 UDPSTAT_INC(udps_noportbcast); 570 goto badheadlocked; 571 } 572 up = intoudpcb(last); 573 if (up->u_tun_func == NULL) { 574 udp_append(last, ip, m, iphlen + sizeof(struct udphdr), 575 &udp_in); 576 } else { 577 /* 578 * Engage the tunneling protocol. 579 */ 580 (*up->u_tun_func)(m, iphlen, last); 581 } 582 INP_RUNLOCK(last); 583 INP_INFO_RUNLOCK(&V_udbinfo); 584 return; 585 } 586 587 /* 588 * Locate pcb for datagram. 589 */ 590 inp = in_pcblookup_hash(&V_udbinfo, ip->ip_src, uh->uh_sport, 591 ip->ip_dst, uh->uh_dport, 1, ifp); 592 if (inp == NULL) { 593 if (udp_log_in_vain) { 594 char buf[4*sizeof "123"]; 595 596 strcpy(buf, inet_ntoa(ip->ip_dst)); 597 log(LOG_INFO, 598 "Connection attempt to UDP %s:%d from %s:%d\n", 599 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 600 ntohs(uh->uh_sport)); 601 } 602 UDPSTAT_INC(udps_noport); 603 if (m->m_flags & (M_BCAST | M_MCAST)) { 604 UDPSTAT_INC(udps_noportbcast); 605 goto badheadlocked; 606 } 607 if (V_udp_blackhole) 608 goto badheadlocked; 609 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 610 goto badheadlocked; 611 *ip = save_ip; 612 ip->ip_len += iphlen; 613 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 614 INP_INFO_RUNLOCK(&V_udbinfo); 615 return; 616 } 617 618 /* 619 * Check the minimum TTL for socket. 620 */ 621 INP_RLOCK(inp); 622 INP_INFO_RUNLOCK(&V_udbinfo); 623 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) { 624 INP_RUNLOCK(inp); 625 goto badunlocked; 626 } 627 up = intoudpcb(inp); 628 if (up->u_tun_func == NULL) { 629 udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in); 630 } else { 631 /* 632 * Engage the tunneling protocol. 633 */ 634 635 (*up->u_tun_func)(m, iphlen, inp); 636 } 637 INP_RUNLOCK(inp); 638 return; 639 640 badheadlocked: 641 if (inp) 642 INP_RUNLOCK(inp); 643 INP_INFO_RUNLOCK(&V_udbinfo); 644 badunlocked: 645 m_freem(m); 646 } 647 648 /* 649 * Notify a udp user of an asynchronous error; just wake up so that they can 650 * collect error status. 651 */ 652 struct inpcb * 653 udp_notify(struct inpcb *inp, int errno) 654 { 655 656 /* 657 * While udp_ctlinput() always calls udp_notify() with a read lock 658 * when invoking it directly, in_pcbnotifyall() currently uses write 659 * locks due to sharing code with TCP. For now, accept either a read 660 * or a write lock, but a read lock is sufficient. 661 */ 662 INP_LOCK_ASSERT(inp); 663 664 inp->inp_socket->so_error = errno; 665 sorwakeup(inp->inp_socket); 666 sowwakeup(inp->inp_socket); 667 return (inp); 668 } 669 670 void 671 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 672 { 673 struct ip *ip = vip; 674 struct udphdr *uh; 675 struct in_addr faddr; 676 struct inpcb *inp; 677 678 faddr = ((struct sockaddr_in *)sa)->sin_addr; 679 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 680 return; 681 682 /* 683 * Redirects don't need to be handled up here. 684 */ 685 if (PRC_IS_REDIRECT(cmd)) 686 return; 687 688 /* 689 * Hostdead is ugly because it goes linearly through all PCBs. 690 * 691 * XXX: We never get this from ICMP, otherwise it makes an excellent 692 * DoS attack on machines with many connections. 693 */ 694 if (cmd == PRC_HOSTDEAD) 695 ip = NULL; 696 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 697 return; 698 if (ip != NULL) { 699 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 700 INP_INFO_RLOCK(&V_udbinfo); 701 inp = in_pcblookup_hash(&V_udbinfo, faddr, uh->uh_dport, 702 ip->ip_src, uh->uh_sport, 0, NULL); 703 if (inp != NULL) { 704 INP_RLOCK(inp); 705 if (inp->inp_socket != NULL) { 706 udp_notify(inp, inetctlerrmap[cmd]); 707 } 708 INP_RUNLOCK(inp); 709 } 710 INP_INFO_RUNLOCK(&V_udbinfo); 711 } else 712 in_pcbnotifyall(&V_udbinfo, faddr, inetctlerrmap[cmd], 713 udp_notify); 714 } 715 716 static int 717 udp_pcblist(SYSCTL_HANDLER_ARGS) 718 { 719 int error, i, n; 720 struct inpcb *inp, **inp_list; 721 inp_gen_t gencnt; 722 struct xinpgen xig; 723 724 /* 725 * The process of preparing the PCB list is too time-consuming and 726 * resource-intensive to repeat twice on every request. 727 */ 728 if (req->oldptr == 0) { 729 n = V_udbinfo.ipi_count; 730 req->oldidx = 2 * (sizeof xig) 731 + (n + n/8) * sizeof(struct xinpcb); 732 return (0); 733 } 734 735 if (req->newptr != 0) 736 return (EPERM); 737 738 /* 739 * OK, now we're committed to doing something. 740 */ 741 INP_INFO_RLOCK(&V_udbinfo); 742 gencnt = V_udbinfo.ipi_gencnt; 743 n = V_udbinfo.ipi_count; 744 INP_INFO_RUNLOCK(&V_udbinfo); 745 746 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 747 + n * sizeof(struct xinpcb)); 748 if (error != 0) 749 return (error); 750 751 xig.xig_len = sizeof xig; 752 xig.xig_count = n; 753 xig.xig_gen = gencnt; 754 xig.xig_sogen = so_gencnt; 755 error = SYSCTL_OUT(req, &xig, sizeof xig); 756 if (error) 757 return (error); 758 759 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 760 if (inp_list == 0) 761 return (ENOMEM); 762 763 INP_INFO_RLOCK(&V_udbinfo); 764 for (inp = LIST_FIRST(V_udbinfo.ipi_listhead), i = 0; inp && i < n; 765 inp = LIST_NEXT(inp, inp_list)) { 766 INP_RLOCK(inp); 767 if (inp->inp_gencnt <= gencnt && 768 cr_canseeinpcb(req->td->td_ucred, inp) == 0) 769 inp_list[i++] = inp; 770 INP_RUNLOCK(inp); 771 } 772 INP_INFO_RUNLOCK(&V_udbinfo); 773 n = i; 774 775 error = 0; 776 for (i = 0; i < n; i++) { 777 inp = inp_list[i]; 778 INP_RLOCK(inp); 779 if (inp->inp_gencnt <= gencnt) { 780 struct xinpcb xi; 781 bzero(&xi, sizeof(xi)); 782 xi.xi_len = sizeof xi; 783 /* XXX should avoid extra copy */ 784 bcopy(inp, &xi.xi_inp, sizeof *inp); 785 if (inp->inp_socket) 786 sotoxsocket(inp->inp_socket, &xi.xi_socket); 787 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 788 INP_RUNLOCK(inp); 789 error = SYSCTL_OUT(req, &xi, sizeof xi); 790 } else 791 INP_RUNLOCK(inp); 792 } 793 if (!error) { 794 /* 795 * Give the user an updated idea of our state. If the 796 * generation differs from what we told her before, she knows 797 * that something happened while we were processing this 798 * request, and it might be necessary to retry. 799 */ 800 INP_INFO_RLOCK(&V_udbinfo); 801 xig.xig_gen = V_udbinfo.ipi_gencnt; 802 xig.xig_sogen = so_gencnt; 803 xig.xig_count = V_udbinfo.ipi_count; 804 INP_INFO_RUNLOCK(&V_udbinfo); 805 error = SYSCTL_OUT(req, &xig, sizeof xig); 806 } 807 free(inp_list, M_TEMP); 808 return (error); 809 } 810 811 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 812 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 813 814 static int 815 udp_getcred(SYSCTL_HANDLER_ARGS) 816 { 817 struct xucred xuc; 818 struct sockaddr_in addrs[2]; 819 struct inpcb *inp; 820 int error; 821 822 error = priv_check(req->td, PRIV_NETINET_GETCRED); 823 if (error) 824 return (error); 825 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 826 if (error) 827 return (error); 828 INP_INFO_RLOCK(&V_udbinfo); 829 inp = in_pcblookup_hash(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 830 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL); 831 if (inp != NULL) { 832 INP_RLOCK(inp); 833 INP_INFO_RUNLOCK(&V_udbinfo); 834 if (inp->inp_socket == NULL) 835 error = ENOENT; 836 if (error == 0) 837 error = cr_canseeinpcb(req->td->td_ucred, inp); 838 if (error == 0) 839 cru2x(inp->inp_cred, &xuc); 840 INP_RUNLOCK(inp); 841 } else { 842 INP_INFO_RUNLOCK(&V_udbinfo); 843 error = ENOENT; 844 } 845 if (error == 0) 846 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 847 return (error); 848 } 849 850 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 851 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 852 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 853 854 int 855 udp_ctloutput(struct socket *so, struct sockopt *sopt) 856 { 857 int error = 0, optval; 858 struct inpcb *inp; 859 #ifdef IPSEC_NAT_T 860 struct udpcb *up; 861 #endif 862 863 inp = sotoinpcb(so); 864 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 865 INP_WLOCK(inp); 866 if (sopt->sopt_level != IPPROTO_UDP) { 867 #ifdef INET6 868 if (INP_CHECK_SOCKAF(so, AF_INET6)) { 869 INP_WUNLOCK(inp); 870 error = ip6_ctloutput(so, sopt); 871 } else { 872 #endif 873 INP_WUNLOCK(inp); 874 error = ip_ctloutput(so, sopt); 875 #ifdef INET6 876 } 877 #endif 878 return (error); 879 } 880 881 switch (sopt->sopt_dir) { 882 case SOPT_SET: 883 switch (sopt->sopt_name) { 884 case UDP_ENCAP: 885 INP_WUNLOCK(inp); 886 error = sooptcopyin(sopt, &optval, sizeof optval, 887 sizeof optval); 888 if (error) 889 break; 890 inp = sotoinpcb(so); 891 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 892 INP_WLOCK(inp); 893 #ifdef IPSEC_NAT_T 894 up = intoudpcb(inp); 895 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 896 #endif 897 switch (optval) { 898 case 0: 899 /* Clear all UDP encap. */ 900 #ifdef IPSEC_NAT_T 901 up->u_flags &= ~UF_ESPINUDP_ALL; 902 #endif 903 break; 904 #ifdef IPSEC_NAT_T 905 case UDP_ENCAP_ESPINUDP: 906 case UDP_ENCAP_ESPINUDP_NON_IKE: 907 up->u_flags &= ~UF_ESPINUDP_ALL; 908 if (optval == UDP_ENCAP_ESPINUDP) 909 up->u_flags |= UF_ESPINUDP; 910 else if (optval == UDP_ENCAP_ESPINUDP_NON_IKE) 911 up->u_flags |= UF_ESPINUDP_NON_IKE; 912 break; 913 #endif 914 default: 915 error = EINVAL; 916 break; 917 } 918 INP_WUNLOCK(inp); 919 break; 920 default: 921 INP_WUNLOCK(inp); 922 error = ENOPROTOOPT; 923 break; 924 } 925 break; 926 case SOPT_GET: 927 switch (sopt->sopt_name) { 928 #ifdef IPSEC_NAT_T 929 case UDP_ENCAP: 930 up = intoudpcb(inp); 931 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 932 optval = up->u_flags & UF_ESPINUDP_ALL; 933 INP_WUNLOCK(inp); 934 error = sooptcopyout(sopt, &optval, sizeof optval); 935 break; 936 #endif 937 default: 938 INP_WUNLOCK(inp); 939 error = ENOPROTOOPT; 940 break; 941 } 942 break; 943 } 944 return (error); 945 } 946 947 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; 960 961 /* 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 if (control != NULL) { 976 /* 977 * XXX: Currently, we assume all the optional information is 978 * stored in a single mbuf. 979 */ 980 if (control->m_next) { 981 m_freem(control); 982 m_freem(m); 983 return (EINVAL); 984 } 985 for (; control->m_len > 0; 986 control->m_data += CMSG_ALIGN(cm->cmsg_len), 987 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 988 cm = mtod(control, struct cmsghdr *); 989 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 990 || cm->cmsg_len > control->m_len) { 991 error = EINVAL; 992 break; 993 } 994 if (cm->cmsg_level != IPPROTO_IP) 995 continue; 996 997 switch (cm->cmsg_type) { 998 case IP_SENDSRCADDR: 999 if (cm->cmsg_len != 1000 CMSG_LEN(sizeof(struct in_addr))) { 1001 error = EINVAL; 1002 break; 1003 } 1004 bzero(&src, sizeof(src)); 1005 src.sin_family = AF_INET; 1006 src.sin_len = sizeof(src); 1007 src.sin_port = inp->inp_lport; 1008 src.sin_addr = 1009 *(struct in_addr *)CMSG_DATA(cm); 1010 break; 1011 1012 default: 1013 error = ENOPROTOOPT; 1014 break; 1015 } 1016 if (error) 1017 break; 1018 } 1019 m_freem(control); 1020 } 1021 if (error) { 1022 m_freem(m); 1023 return (error); 1024 } 1025 1026 /* 1027 * Depending on whether or not the application has bound or connected 1028 * the socket, we may have to do varying levels of work. The optimal 1029 * case is for a connected UDP socket, as a global lock isn't 1030 * required at all. 1031 * 1032 * In order to decide which we need, we require stability of the 1033 * inpcb binding, which we ensure by acquiring a read lock on the 1034 * inpcb. This doesn't strictly follow the lock order, so we play 1035 * the trylock and retry game; note that we may end up with more 1036 * conservative locks than required the second time around, so later 1037 * assertions have to accept that. Further analysis of the number of 1038 * misses under contention is required. 1039 */ 1040 sin = (struct sockaddr_in *)addr; 1041 INP_RLOCK(inp); 1042 if (sin != NULL && 1043 (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) { 1044 INP_RUNLOCK(inp); 1045 INP_INFO_WLOCK(&V_udbinfo); 1046 INP_WLOCK(inp); 1047 unlock_udbinfo = 2; 1048 } else if ((sin != NULL && ( 1049 (sin->sin_addr.s_addr == INADDR_ANY) || 1050 (sin->sin_addr.s_addr == INADDR_BROADCAST) || 1051 (inp->inp_laddr.s_addr == INADDR_ANY) || 1052 (inp->inp_lport == 0))) || 1053 (src.sin_family == AF_INET)) { 1054 if (!INP_INFO_TRY_RLOCK(&V_udbinfo)) { 1055 INP_RUNLOCK(inp); 1056 INP_INFO_RLOCK(&V_udbinfo); 1057 INP_RLOCK(inp); 1058 } 1059 unlock_udbinfo = 1; 1060 } else 1061 unlock_udbinfo = 0; 1062 1063 /* 1064 * If the IP_SENDSRCADDR control message was specified, override the 1065 * source address for this datagram. Its use is invalidated if the 1066 * address thus specified is incomplete or clobbers other inpcbs. 1067 */ 1068 laddr = inp->inp_laddr; 1069 lport = inp->inp_lport; 1070 if (src.sin_family == AF_INET) { 1071 INP_INFO_LOCK_ASSERT(&V_udbinfo); 1072 if ((lport == 0) || 1073 (laddr.s_addr == INADDR_ANY && 1074 src.sin_addr.s_addr == INADDR_ANY)) { 1075 error = EINVAL; 1076 goto release; 1077 } 1078 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 1079 &laddr.s_addr, &lport, td->td_ucred); 1080 if (error) 1081 goto release; 1082 } 1083 1084 /* 1085 * If a UDP socket has been connected, then a local address/port will 1086 * have been selected and bound. 1087 * 1088 * If a UDP socket has not been connected to, then an explicit 1089 * destination address must be used, in which case a local 1090 * address/port may not have been selected and bound. 1091 */ 1092 if (sin != NULL) { 1093 INP_LOCK_ASSERT(inp); 1094 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1095 error = EISCONN; 1096 goto release; 1097 } 1098 1099 /* 1100 * Jail may rewrite the destination address, so let it do 1101 * that before we use it. 1102 */ 1103 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1104 if (error) 1105 goto release; 1106 1107 /* 1108 * If a local address or port hasn't yet been selected, or if 1109 * the destination address needs to be rewritten due to using 1110 * a special INADDR_ constant, invoke in_pcbconnect_setup() 1111 * to do the heavy lifting. Once a port is selected, we 1112 * commit the binding back to the socket; we also commit the 1113 * binding of the address if in jail. 1114 * 1115 * If we already have a valid binding and we're not 1116 * requesting a destination address rewrite, use a fast path. 1117 */ 1118 if (inp->inp_laddr.s_addr == INADDR_ANY || 1119 inp->inp_lport == 0 || 1120 sin->sin_addr.s_addr == INADDR_ANY || 1121 sin->sin_addr.s_addr == INADDR_BROADCAST) { 1122 INP_INFO_LOCK_ASSERT(&V_udbinfo); 1123 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, 1124 &lport, &faddr.s_addr, &fport, NULL, 1125 td->td_ucred); 1126 if (error) 1127 goto release; 1128 1129 /* 1130 * XXXRW: Why not commit the port if the address is 1131 * !INADDR_ANY? 1132 */ 1133 /* Commit the local port if newly assigned. */ 1134 if (inp->inp_laddr.s_addr == INADDR_ANY && 1135 inp->inp_lport == 0) { 1136 INP_INFO_WLOCK_ASSERT(&V_udbinfo); 1137 INP_WLOCK_ASSERT(inp); 1138 /* 1139 * Remember addr if jailed, to prevent 1140 * rebinding. 1141 */ 1142 if (prison_flag(td->td_ucred, PR_IP4)) 1143 inp->inp_laddr = laddr; 1144 inp->inp_lport = lport; 1145 if (in_pcbinshash(inp) != 0) { 1146 inp->inp_lport = 0; 1147 error = EAGAIN; 1148 goto release; 1149 } 1150 inp->inp_flags |= INP_ANONPORT; 1151 } 1152 } else { 1153 faddr = sin->sin_addr; 1154 fport = sin->sin_port; 1155 } 1156 } else { 1157 INP_LOCK_ASSERT(inp); 1158 faddr = inp->inp_faddr; 1159 fport = inp->inp_fport; 1160 if (faddr.s_addr == INADDR_ANY) { 1161 error = ENOTCONN; 1162 goto release; 1163 } 1164 } 1165 1166 /* 1167 * Calculate data length and get a mbuf for UDP, IP, and possible 1168 * link-layer headers. Immediate slide the data pointer back forward 1169 * since we won't use that space at this layer. 1170 */ 1171 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT); 1172 if (m == NULL) { 1173 error = ENOBUFS; 1174 goto release; 1175 } 1176 m->m_data += max_linkhdr; 1177 m->m_len -= max_linkhdr; 1178 m->m_pkthdr.len -= max_linkhdr; 1179 1180 /* 1181 * Fill in mbuf with extended UDP header and addresses and length put 1182 * into network format. 1183 */ 1184 ui = mtod(m, struct udpiphdr *); 1185 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 1186 ui->ui_pr = IPPROTO_UDP; 1187 ui->ui_src = laddr; 1188 ui->ui_dst = faddr; 1189 ui->ui_sport = lport; 1190 ui->ui_dport = fport; 1191 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 1192 1193 /* 1194 * Set the Don't Fragment bit in the IP header. 1195 */ 1196 if (inp->inp_flags & INP_DONTFRAG) { 1197 struct ip *ip; 1198 1199 ip = (struct ip *)&ui->ui_i; 1200 ip->ip_off |= IP_DF; 1201 } 1202 1203 ipflags = 0; 1204 if (inp->inp_socket->so_options & SO_DONTROUTE) 1205 ipflags |= IP_ROUTETOIF; 1206 if (inp->inp_socket->so_options & SO_BROADCAST) 1207 ipflags |= IP_ALLOWBROADCAST; 1208 if (inp->inp_flags & INP_ONESBCAST) 1209 ipflags |= IP_SENDONES; 1210 1211 #ifdef MAC 1212 mac_inpcb_create_mbuf(inp, m); 1213 #endif 1214 1215 /* 1216 * Set up checksum and output datagram. 1217 */ 1218 if (udp_cksum) { 1219 if (inp->inp_flags & INP_ONESBCAST) 1220 faddr.s_addr = INADDR_BROADCAST; 1221 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 1222 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 1223 m->m_pkthdr.csum_flags = CSUM_UDP; 1224 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 1225 } else 1226 ui->ui_sum = 0; 1227 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 1228 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 1229 ((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */ 1230 UDPSTAT_INC(udps_opackets); 1231 1232 if (unlock_udbinfo == 2) 1233 INP_INFO_WUNLOCK(&V_udbinfo); 1234 else if (unlock_udbinfo == 1) 1235 INP_INFO_RUNLOCK(&V_udbinfo); 1236 error = ip_output(m, inp->inp_options, NULL, ipflags, 1237 inp->inp_moptions, inp); 1238 if (unlock_udbinfo == 2) 1239 INP_WUNLOCK(inp); 1240 else 1241 INP_RUNLOCK(inp); 1242 return (error); 1243 1244 release: 1245 if (unlock_udbinfo == 2) { 1246 INP_WUNLOCK(inp); 1247 INP_INFO_WUNLOCK(&V_udbinfo); 1248 } else if (unlock_udbinfo == 1) { 1249 INP_RUNLOCK(inp); 1250 INP_INFO_RUNLOCK(&V_udbinfo); 1251 } else 1252 INP_RUNLOCK(inp); 1253 m_freem(m); 1254 return (error); 1255 } 1256 1257 1258 #if defined(IPSEC) && defined(IPSEC_NAT_T) 1259 #ifdef INET 1260 /* 1261 * Potentially decap ESP in UDP frame. Check for an ESP header 1262 * and optional marker; if present, strip the UDP header and 1263 * push the result through IPSec. 1264 * 1265 * Returns mbuf to be processed (potentially re-allocated) or 1266 * NULL if consumed and/or processed. 1267 */ 1268 static struct mbuf * 1269 udp4_espdecap(struct inpcb *inp, struct mbuf *m, int off) 1270 { 1271 size_t minlen, payload, skip, iphlen; 1272 caddr_t data; 1273 struct udpcb *up; 1274 struct m_tag *tag; 1275 struct udphdr *udphdr; 1276 struct ip *ip; 1277 1278 INP_RLOCK_ASSERT(inp); 1279 1280 /* 1281 * Pull up data so the longest case is contiguous: 1282 * IP/UDP hdr + non ESP marker + ESP hdr. 1283 */ 1284 minlen = off + sizeof(uint64_t) + sizeof(struct esp); 1285 if (minlen > m->m_pkthdr.len) 1286 minlen = m->m_pkthdr.len; 1287 if ((m = m_pullup(m, minlen)) == NULL) { 1288 V_ipsec4stat.in_inval++; 1289 return (NULL); /* Bypass caller processing. */ 1290 } 1291 data = mtod(m, caddr_t); /* Points to ip header. */ 1292 payload = m->m_len - off; /* Size of payload. */ 1293 1294 if (payload == 1 && data[off] == '\xff') 1295 return (m); /* NB: keepalive packet, no decap. */ 1296 1297 up = intoudpcb(inp); 1298 KASSERT(up != NULL, ("%s: udpcb NULL", __func__)); 1299 KASSERT((up->u_flags & UF_ESPINUDP_ALL) != 0, 1300 ("u_flags 0x%x", up->u_flags)); 1301 1302 /* 1303 * Check that the payload is large enough to hold an 1304 * ESP header and compute the amount of data to remove. 1305 * 1306 * NB: the caller has already done a pullup for us. 1307 * XXX can we assume alignment and eliminate bcopys? 1308 */ 1309 if (up->u_flags & UF_ESPINUDP_NON_IKE) { 1310 /* 1311 * draft-ietf-ipsec-nat-t-ike-0[01].txt and 1312 * draft-ietf-ipsec-udp-encaps-(00/)01.txt, ignoring 1313 * possible AH mode non-IKE marker+non-ESP marker 1314 * from draft-ietf-ipsec-udp-encaps-00.txt. 1315 */ 1316 uint64_t marker; 1317 1318 if (payload <= sizeof(uint64_t) + sizeof(struct esp)) 1319 return (m); /* NB: no decap. */ 1320 bcopy(data + off, &marker, sizeof(uint64_t)); 1321 if (marker != 0) /* Non-IKE marker. */ 1322 return (m); /* NB: no decap. */ 1323 skip = sizeof(uint64_t) + sizeof(struct udphdr); 1324 } else { 1325 uint32_t spi; 1326 1327 if (payload <= sizeof(struct esp)) { 1328 V_ipsec4stat.in_inval++; 1329 m_freem(m); 1330 return (NULL); /* Discard. */ 1331 } 1332 bcopy(data + off, &spi, sizeof(uint32_t)); 1333 if (spi == 0) /* Non-ESP marker. */ 1334 return (m); /* NB: no decap. */ 1335 skip = sizeof(struct udphdr); 1336 } 1337 1338 /* 1339 * Setup a PACKET_TAG_IPSEC_NAT_T_PORT tag to remember 1340 * the UDP ports. This is required if we want to select 1341 * the right SPD for multiple hosts behind same NAT. 1342 * 1343 * NB: ports are maintained in network byte order everywhere 1344 * in the NAT-T code. 1345 */ 1346 tag = m_tag_get(PACKET_TAG_IPSEC_NAT_T_PORTS, 1347 2 * sizeof(uint16_t), M_NOWAIT); 1348 if (tag == NULL) { 1349 V_ipsec4stat.in_nomem++; 1350 m_freem(m); 1351 return (NULL); /* Discard. */ 1352 } 1353 iphlen = off - sizeof(struct udphdr); 1354 udphdr = (struct udphdr *)(data + iphlen); 1355 ((uint16_t *)(tag + 1))[0] = udphdr->uh_sport; 1356 ((uint16_t *)(tag + 1))[1] = udphdr->uh_dport; 1357 m_tag_prepend(m, tag); 1358 1359 /* 1360 * Remove the UDP header (and possibly the non ESP marker) 1361 * IP header length is iphlen 1362 * Before: 1363 * <--- off ---> 1364 * +----+------+-----+ 1365 * | IP | UDP | ESP | 1366 * +----+------+-----+ 1367 * <-skip-> 1368 * After: 1369 * +----+-----+ 1370 * | IP | ESP | 1371 * +----+-----+ 1372 * <-skip-> 1373 */ 1374 ovbcopy(data, data + skip, iphlen); 1375 m_adj(m, skip); 1376 1377 ip = mtod(m, struct ip *); 1378 ip->ip_len -= skip; 1379 ip->ip_p = IPPROTO_ESP; 1380 1381 /* 1382 * We cannot yet update the cksums so clear any 1383 * h/w cksum flags as they are no longer valid. 1384 */ 1385 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) 1386 m->m_pkthdr.csum_flags &= ~(CSUM_DATA_VALID|CSUM_PSEUDO_HDR); 1387 1388 (void) ipsec4_common_input(m, iphlen, ip->ip_p); 1389 return (NULL); /* NB: consumed, bypass processing. */ 1390 } 1391 #endif /* INET */ 1392 #endif /* defined(IPSEC) && defined(IPSEC_NAT_T) */ 1393 1394 static void 1395 udp_abort(struct socket *so) 1396 { 1397 struct inpcb *inp; 1398 1399 inp = sotoinpcb(so); 1400 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 1401 INP_INFO_WLOCK(&V_udbinfo); 1402 INP_WLOCK(inp); 1403 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1404 in_pcbdisconnect(inp); 1405 inp->inp_laddr.s_addr = INADDR_ANY; 1406 soisdisconnected(so); 1407 } 1408 INP_WUNLOCK(inp); 1409 INP_INFO_WUNLOCK(&V_udbinfo); 1410 } 1411 1412 static int 1413 udp_attach(struct socket *so, int proto, struct thread *td) 1414 { 1415 struct inpcb *inp; 1416 int error; 1417 1418 inp = sotoinpcb(so); 1419 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 1420 error = soreserve(so, udp_sendspace, udp_recvspace); 1421 if (error) 1422 return (error); 1423 INP_INFO_WLOCK(&V_udbinfo); 1424 error = in_pcballoc(so, &V_udbinfo); 1425 if (error) { 1426 INP_INFO_WUNLOCK(&V_udbinfo); 1427 return (error); 1428 } 1429 1430 inp = (struct inpcb *)so->so_pcb; 1431 inp->inp_vflag |= INP_IPV4; 1432 inp->inp_ip_ttl = V_ip_defttl; 1433 1434 error = udp_newudpcb(inp); 1435 if (error) { 1436 in_pcbdetach(inp); 1437 in_pcbfree(inp); 1438 INP_INFO_WUNLOCK(&V_udbinfo); 1439 return (error); 1440 } 1441 1442 INP_WUNLOCK(inp); 1443 INP_INFO_WUNLOCK(&V_udbinfo); 1444 return (0); 1445 } 1446 1447 int 1448 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f) 1449 { 1450 struct inpcb *inp; 1451 struct udpcb *up; 1452 1453 KASSERT(so->so_type == SOCK_DGRAM, ("udp_set_kernel_tunneling: !dgram")); 1454 KASSERT(so->so_pcb != NULL, ("udp_set_kernel_tunneling: NULL inp")); 1455 if (so->so_type != SOCK_DGRAM) { 1456 /* Not UDP socket... sorry! */ 1457 return (ENOTSUP); 1458 } 1459 inp = (struct inpcb *)so->so_pcb; 1460 if (inp == NULL) { 1461 /* NULL INP? */ 1462 return (EINVAL); 1463 } 1464 INP_WLOCK(inp); 1465 up = intoudpcb(inp); 1466 if (up->u_tun_func != NULL) { 1467 INP_WUNLOCK(inp); 1468 return (EBUSY); 1469 } 1470 up->u_tun_func = f; 1471 INP_WUNLOCK(inp); 1472 return (0); 1473 } 1474 1475 static int 1476 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1477 { 1478 struct inpcb *inp; 1479 int error; 1480 1481 inp = sotoinpcb(so); 1482 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1483 INP_INFO_WLOCK(&V_udbinfo); 1484 INP_WLOCK(inp); 1485 error = in_pcbbind(inp, nam, td->td_ucred); 1486 INP_WUNLOCK(inp); 1487 INP_INFO_WUNLOCK(&V_udbinfo); 1488 return (error); 1489 } 1490 1491 static void 1492 udp_close(struct socket *so) 1493 { 1494 struct inpcb *inp; 1495 1496 inp = sotoinpcb(so); 1497 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1498 INP_INFO_WLOCK(&V_udbinfo); 1499 INP_WLOCK(inp); 1500 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1501 in_pcbdisconnect(inp); 1502 inp->inp_laddr.s_addr = INADDR_ANY; 1503 soisdisconnected(so); 1504 } 1505 INP_WUNLOCK(inp); 1506 INP_INFO_WUNLOCK(&V_udbinfo); 1507 } 1508 1509 static int 1510 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1511 { 1512 struct inpcb *inp; 1513 int error; 1514 struct sockaddr_in *sin; 1515 1516 inp = sotoinpcb(so); 1517 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1518 INP_INFO_WLOCK(&V_udbinfo); 1519 INP_WLOCK(inp); 1520 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1521 INP_WUNLOCK(inp); 1522 INP_INFO_WUNLOCK(&V_udbinfo); 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 INP_INFO_WUNLOCK(&V_udbinfo); 1530 return (error); 1531 } 1532 error = in_pcbconnect(inp, nam, td->td_ucred); 1533 if (error == 0) 1534 soisconnected(so); 1535 INP_WUNLOCK(inp); 1536 INP_INFO_WUNLOCK(&V_udbinfo); 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_INFO_WLOCK(&V_udbinfo); 1569 INP_WLOCK(inp); 1570 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1571 INP_WUNLOCK(inp); 1572 INP_INFO_WUNLOCK(&V_udbinfo); 1573 return (ENOTCONN); 1574 } 1575 1576 in_pcbdisconnect(inp); 1577 inp->inp_laddr.s_addr = INADDR_ANY; 1578 SOCK_LOCK(so); 1579 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1580 SOCK_UNLOCK(so); 1581 INP_WUNLOCK(inp); 1582 INP_INFO_WUNLOCK(&V_udbinfo); 1583 return (0); 1584 } 1585 1586 static int 1587 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1588 struct mbuf *control, struct thread *td) 1589 { 1590 struct inpcb *inp; 1591 1592 inp = sotoinpcb(so); 1593 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1594 return (udp_output(inp, m, addr, control, td)); 1595 } 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 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