1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 5 * The Regents of the University of California. 6 * Copyright (c) 2008 Robert N. M. Watson 7 * Copyright (c) 2010-2011 Juniper Networks, Inc. 8 * Copyright (c) 2014 Kevin Lo 9 * All rights reserved. 10 * 11 * Portions of this software were developed by Robert N. M. Watson under 12 * contract to Juniper Networks, Inc. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include "opt_inet.h" 45 #include "opt_inet6.h" 46 #include "opt_ipsec.h" 47 #include "opt_rss.h" 48 49 #include <sys/param.h> 50 #include <sys/domain.h> 51 #include <sys/eventhandler.h> 52 #include <sys/jail.h> 53 #include <sys/kernel.h> 54 #include <sys/lock.h> 55 #include <sys/malloc.h> 56 #include <sys/mbuf.h> 57 #include <sys/priv.h> 58 #include <sys/proc.h> 59 #include <sys/protosw.h> 60 #include <sys/sdt.h> 61 #include <sys/signalvar.h> 62 #include <sys/socket.h> 63 #include <sys/socketvar.h> 64 #include <sys/sx.h> 65 #include <sys/sysctl.h> 66 #include <sys/syslog.h> 67 #include <sys/systm.h> 68 69 #include <vm/uma.h> 70 71 #include <net/if.h> 72 #include <net/if_var.h> 73 #include <net/route.h> 74 #include <net/route/nhop.h> 75 #include <net/rss_config.h> 76 77 #include <netinet/in.h> 78 #include <netinet/in_kdtrace.h> 79 #include <netinet/in_pcb.h> 80 #include <netinet/in_systm.h> 81 #include <netinet/in_var.h> 82 #include <netinet/ip.h> 83 #ifdef INET6 84 #include <netinet/ip6.h> 85 #endif 86 #include <netinet/ip_icmp.h> 87 #include <netinet/icmp_var.h> 88 #include <netinet/ip_var.h> 89 #include <netinet/ip_options.h> 90 #ifdef INET6 91 #include <netinet6/ip6_var.h> 92 #endif 93 #include <netinet/udp.h> 94 #include <netinet/udp_var.h> 95 #include <netinet/udplite.h> 96 #include <netinet/in_rss.h> 97 98 #include <netipsec/ipsec_support.h> 99 100 #include <machine/in_cksum.h> 101 102 #include <security/mac/mac_framework.h> 103 104 /* 105 * UDP and UDP-Lite protocols implementation. 106 * Per RFC 768, August, 1980. 107 * Per RFC 3828, July, 2004. 108 */ 109 110 /* 111 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums 112 * removes the only data integrity mechanism for packets and malformed 113 * packets that would otherwise be discarded due to bad checksums, and may 114 * cause problems (especially for NFS data blocks). 115 */ 116 VNET_DEFINE(int, udp_cksum) = 1; 117 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW, 118 &VNET_NAME(udp_cksum), 0, "compute udp checksum"); 119 120 VNET_DEFINE(int, udp_log_in_vain) = 0; 121 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW, 122 &VNET_NAME(udp_log_in_vain), 0, "Log all incoming UDP packets"); 123 124 VNET_DEFINE(int, udp_blackhole) = 0; 125 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW, 126 &VNET_NAME(udp_blackhole), 0, 127 "Do not send port unreachables for refused connects"); 128 129 u_long udp_sendspace = 9216; /* really max datagram size */ 130 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 131 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 132 133 u_long udp_recvspace = 40 * (1024 + 134 #ifdef INET6 135 sizeof(struct sockaddr_in6) 136 #else 137 sizeof(struct sockaddr_in) 138 #endif 139 ); /* 40 1K datagrams */ 140 141 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 142 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 143 144 VNET_DEFINE(struct inpcbhead, udb); /* from udp_var.h */ 145 VNET_DEFINE(struct inpcbinfo, udbinfo); 146 VNET_DEFINE(struct inpcbhead, ulitecb); 147 VNET_DEFINE(struct inpcbinfo, ulitecbinfo); 148 VNET_DEFINE_STATIC(uma_zone_t, udpcb_zone); 149 #define V_udpcb_zone VNET(udpcb_zone) 150 151 #ifndef UDBHASHSIZE 152 #define UDBHASHSIZE 128 153 #endif 154 155 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat); /* from udp_var.h */ 156 VNET_PCPUSTAT_SYSINIT(udpstat); 157 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat, 158 udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)"); 159 160 #ifdef VIMAGE 161 VNET_PCPUSTAT_SYSUNINIT(udpstat); 162 #endif /* VIMAGE */ 163 #ifdef INET 164 static void udp_detach(struct socket *so); 165 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 166 struct mbuf *, struct thread *, int); 167 #endif 168 169 static void 170 udp_zone_change(void *tag) 171 { 172 173 uma_zone_set_max(V_udbinfo.ipi_zone, maxsockets); 174 uma_zone_set_max(V_udpcb_zone, maxsockets); 175 } 176 177 static int 178 udp_inpcb_init(void *mem, int size, int flags) 179 { 180 struct inpcb *inp; 181 182 inp = mem; 183 INP_LOCK_INIT(inp, "inp", "udpinp"); 184 return (0); 185 } 186 187 static int 188 udplite_inpcb_init(void *mem, int size, int flags) 189 { 190 struct inpcb *inp; 191 192 inp = mem; 193 INP_LOCK_INIT(inp, "inp", "udpliteinp"); 194 return (0); 195 } 196 197 void 198 udp_init(void) 199 { 200 201 /* 202 * For now default to 2-tuple UDP hashing - until the fragment 203 * reassembly code can also update the flowid. 204 * 205 * Once we can calculate the flowid that way and re-establish 206 * a 4-tuple, flip this to 4-tuple. 207 */ 208 in_pcbinfo_init(&V_udbinfo, "udp", &V_udb, UDBHASHSIZE, UDBHASHSIZE, 209 "udp_inpcb", udp_inpcb_init, IPI_HASHFIELDS_2TUPLE); 210 V_udpcb_zone = uma_zcreate("udpcb", sizeof(struct udpcb), 211 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 212 uma_zone_set_max(V_udpcb_zone, maxsockets); 213 uma_zone_set_warning(V_udpcb_zone, "kern.ipc.maxsockets limit reached"); 214 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL, 215 EVENTHANDLER_PRI_ANY); 216 } 217 218 void 219 udplite_init(void) 220 { 221 222 in_pcbinfo_init(&V_ulitecbinfo, "udplite", &V_ulitecb, UDBHASHSIZE, 223 UDBHASHSIZE, "udplite_inpcb", udplite_inpcb_init, 224 IPI_HASHFIELDS_2TUPLE); 225 } 226 227 /* 228 * Kernel module interface for updating udpstat. The argument is an index 229 * into udpstat treated as an array of u_long. While this encodes the 230 * general layout of udpstat into the caller, it doesn't encode its location, 231 * so that future changes to add, for example, per-CPU stats support won't 232 * cause binary compatibility problems for kernel modules. 233 */ 234 void 235 kmod_udpstat_inc(int statnum) 236 { 237 238 counter_u64_add(VNET(udpstat)[statnum], 1); 239 } 240 241 int 242 udp_newudpcb(struct inpcb *inp) 243 { 244 struct udpcb *up; 245 246 up = uma_zalloc(V_udpcb_zone, M_NOWAIT | M_ZERO); 247 if (up == NULL) 248 return (ENOBUFS); 249 inp->inp_ppcb = up; 250 return (0); 251 } 252 253 void 254 udp_discardcb(struct udpcb *up) 255 { 256 257 uma_zfree(V_udpcb_zone, up); 258 } 259 260 #ifdef VIMAGE 261 static void 262 udp_destroy(void *unused __unused) 263 { 264 265 in_pcbinfo_destroy(&V_udbinfo); 266 uma_zdestroy(V_udpcb_zone); 267 } 268 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL); 269 270 static void 271 udplite_destroy(void *unused __unused) 272 { 273 274 in_pcbinfo_destroy(&V_ulitecbinfo); 275 } 276 VNET_SYSUNINIT(udplite, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udplite_destroy, 277 NULL); 278 #endif 279 280 #ifdef INET 281 /* 282 * Subroutine of udp_input(), which appends the provided mbuf chain to the 283 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 284 * contains the source address. If the socket ends up being an IPv6 socket, 285 * udp_append() will convert to a sockaddr_in6 before passing the address 286 * into the socket code. 287 * 288 * In the normal case udp_append() will return 0, indicating that you 289 * must unlock the inp. However if a tunneling protocol is in place we increment 290 * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we 291 * then decrement the reference count. If the inp_rele returns 1, indicating the 292 * inp is gone, we return that to the caller to tell them *not* to unlock 293 * the inp. In the case of multi-cast this will cause the distribution 294 * to stop (though most tunneling protocols known currently do *not* use 295 * multicast). 296 */ 297 static int 298 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off, 299 struct sockaddr_in *udp_in) 300 { 301 struct sockaddr *append_sa; 302 struct socket *so; 303 struct mbuf *tmpopts, *opts = NULL; 304 #ifdef INET6 305 struct sockaddr_in6 udp_in6; 306 #endif 307 struct udpcb *up; 308 309 INP_LOCK_ASSERT(inp); 310 311 /* 312 * Engage the tunneling protocol. 313 */ 314 up = intoudpcb(inp); 315 if (up->u_tun_func != NULL) { 316 in_pcbref(inp); 317 INP_RUNLOCK(inp); 318 (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0], 319 up->u_tun_ctx); 320 INP_RLOCK(inp); 321 return (in_pcbrele_rlocked(inp)); 322 } 323 324 off += sizeof(struct udphdr); 325 326 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 327 /* Check AH/ESP integrity. */ 328 if (IPSEC_ENABLED(ipv4) && 329 IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) { 330 m_freem(n); 331 return (0); 332 } 333 if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */ 334 if (IPSEC_ENABLED(ipv4) && 335 UDPENCAP_INPUT(n, off, AF_INET) != 0) 336 return (0); /* Consumed. */ 337 } 338 #endif /* IPSEC */ 339 #ifdef MAC 340 if (mac_inpcb_check_deliver(inp, n) != 0) { 341 m_freem(n); 342 return (0); 343 } 344 #endif /* MAC */ 345 if (inp->inp_flags & INP_CONTROLOPTS || 346 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 347 #ifdef INET6 348 if (inp->inp_vflag & INP_IPV6) 349 (void)ip6_savecontrol_v4(inp, n, &opts, NULL); 350 else 351 #endif /* INET6 */ 352 ip_savecontrol(inp, &opts, ip, n); 353 } 354 if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) { 355 tmpopts = sbcreatecontrol((caddr_t)&udp_in[1], 356 sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP); 357 if (tmpopts) { 358 if (opts) { 359 tmpopts->m_next = opts; 360 opts = tmpopts; 361 } else 362 opts = tmpopts; 363 } 364 } 365 #ifdef INET6 366 if (inp->inp_vflag & INP_IPV6) { 367 bzero(&udp_in6, sizeof(udp_in6)); 368 udp_in6.sin6_len = sizeof(udp_in6); 369 udp_in6.sin6_family = AF_INET6; 370 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6); 371 append_sa = (struct sockaddr *)&udp_in6; 372 } else 373 #endif /* INET6 */ 374 append_sa = (struct sockaddr *)&udp_in[0]; 375 m_adj(n, off); 376 377 so = inp->inp_socket; 378 SOCKBUF_LOCK(&so->so_rcv); 379 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 380 SOCKBUF_UNLOCK(&so->so_rcv); 381 m_freem(n); 382 if (opts) 383 m_freem(opts); 384 UDPSTAT_INC(udps_fullsock); 385 } else 386 sorwakeup_locked(so); 387 return (0); 388 } 389 390 int 391 udp_input(struct mbuf **mp, int *offp, int proto) 392 { 393 struct ip *ip; 394 struct udphdr *uh; 395 struct ifnet *ifp; 396 struct inpcb *inp; 397 uint16_t len, ip_len; 398 struct inpcbinfo *pcbinfo; 399 struct ip save_ip; 400 struct sockaddr_in udp_in[2]; 401 struct mbuf *m; 402 struct m_tag *fwd_tag; 403 int cscov_partial, iphlen; 404 405 m = *mp; 406 iphlen = *offp; 407 ifp = m->m_pkthdr.rcvif; 408 *mp = NULL; 409 UDPSTAT_INC(udps_ipackets); 410 411 /* 412 * Strip IP options, if any; should skip this, make available to 413 * user, and use on returned packets, but we don't yet have a way to 414 * check the checksum with options still present. 415 */ 416 if (iphlen > sizeof (struct ip)) { 417 ip_stripoptions(m); 418 iphlen = sizeof(struct ip); 419 } 420 421 /* 422 * Get IP and UDP header together in first mbuf. 423 */ 424 if (m->m_len < iphlen + sizeof(struct udphdr)) { 425 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) { 426 UDPSTAT_INC(udps_hdrops); 427 return (IPPROTO_DONE); 428 } 429 } 430 ip = mtod(m, struct ip *); 431 uh = (struct udphdr *)((caddr_t)ip + iphlen); 432 cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0; 433 434 /* 435 * Destination port of 0 is illegal, based on RFC768. 436 */ 437 if (uh->uh_dport == 0) 438 goto badunlocked; 439 440 /* 441 * Construct sockaddr format source address. Stuff source address 442 * and datagram in user buffer. 443 */ 444 bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2); 445 udp_in[0].sin_len = sizeof(struct sockaddr_in); 446 udp_in[0].sin_family = AF_INET; 447 udp_in[0].sin_port = uh->uh_sport; 448 udp_in[0].sin_addr = ip->ip_src; 449 udp_in[1].sin_len = sizeof(struct sockaddr_in); 450 udp_in[1].sin_family = AF_INET; 451 udp_in[1].sin_port = uh->uh_dport; 452 udp_in[1].sin_addr = ip->ip_dst; 453 454 /* 455 * Make mbuf data length reflect UDP length. If not enough data to 456 * reflect UDP length, drop. 457 */ 458 len = ntohs((u_short)uh->uh_ulen); 459 ip_len = ntohs(ip->ip_len) - iphlen; 460 if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) { 461 /* Zero means checksum over the complete packet. */ 462 if (len == 0) 463 len = ip_len; 464 cscov_partial = 0; 465 } 466 if (ip_len != len) { 467 if (len > ip_len || len < sizeof(struct udphdr)) { 468 UDPSTAT_INC(udps_badlen); 469 goto badunlocked; 470 } 471 if (proto == IPPROTO_UDP) 472 m_adj(m, len - ip_len); 473 } 474 475 /* 476 * Save a copy of the IP header in case we want restore it for 477 * sending an ICMP error message in response. 478 */ 479 if (!V_udp_blackhole) 480 save_ip = *ip; 481 else 482 memset(&save_ip, 0, sizeof(save_ip)); 483 484 /* 485 * Checksum extended UDP header and data. 486 */ 487 if (uh->uh_sum) { 488 u_short uh_sum; 489 490 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) && 491 !cscov_partial) { 492 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 493 uh_sum = m->m_pkthdr.csum_data; 494 else 495 uh_sum = in_pseudo(ip->ip_src.s_addr, 496 ip->ip_dst.s_addr, htonl((u_short)len + 497 m->m_pkthdr.csum_data + proto)); 498 uh_sum ^= 0xffff; 499 } else { 500 char b[9]; 501 502 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 503 bzero(((struct ipovly *)ip)->ih_x1, 9); 504 ((struct ipovly *)ip)->ih_len = (proto == IPPROTO_UDP) ? 505 uh->uh_ulen : htons(ip_len); 506 uh_sum = in_cksum(m, len + sizeof (struct ip)); 507 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 508 } 509 if (uh_sum) { 510 UDPSTAT_INC(udps_badsum); 511 m_freem(m); 512 return (IPPROTO_DONE); 513 } 514 } else { 515 if (proto == IPPROTO_UDP) { 516 UDPSTAT_INC(udps_nosum); 517 } else { 518 /* UDPLite requires a checksum */ 519 /* XXX: What is the right UDPLite MIB counter here? */ 520 m_freem(m); 521 return (IPPROTO_DONE); 522 } 523 } 524 525 pcbinfo = udp_get_inpcbinfo(proto); 526 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 527 in_broadcast(ip->ip_dst, ifp)) { 528 struct inpcb *last; 529 struct inpcbhead *pcblist; 530 531 NET_EPOCH_ASSERT(); 532 533 pcblist = udp_get_pcblist(proto); 534 last = NULL; 535 CK_LIST_FOREACH(inp, pcblist, inp_list) { 536 if (inp->inp_lport != uh->uh_dport) 537 continue; 538 #ifdef INET6 539 if ((inp->inp_vflag & INP_IPV4) == 0) 540 continue; 541 #endif 542 if (inp->inp_laddr.s_addr != INADDR_ANY && 543 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 544 continue; 545 if (inp->inp_faddr.s_addr != INADDR_ANY && 546 inp->inp_faddr.s_addr != ip->ip_src.s_addr) 547 continue; 548 if (inp->inp_fport != 0 && 549 inp->inp_fport != uh->uh_sport) 550 continue; 551 552 INP_RLOCK(inp); 553 554 if (__predict_false(inp->inp_flags2 & INP_FREED)) { 555 INP_RUNLOCK(inp); 556 continue; 557 } 558 559 /* 560 * XXXRW: Because we weren't holding either the inpcb 561 * or the hash lock when we checked for a match 562 * before, we should probably recheck now that the 563 * inpcb lock is held. 564 */ 565 566 /* 567 * Handle socket delivery policy for any-source 568 * and source-specific multicast. [RFC3678] 569 */ 570 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 571 struct ip_moptions *imo; 572 struct sockaddr_in group; 573 int blocked; 574 575 imo = inp->inp_moptions; 576 if (imo == NULL) { 577 INP_RUNLOCK(inp); 578 continue; 579 } 580 bzero(&group, sizeof(struct sockaddr_in)); 581 group.sin_len = sizeof(struct sockaddr_in); 582 group.sin_family = AF_INET; 583 group.sin_addr = ip->ip_dst; 584 585 blocked = imo_multi_filter(imo, ifp, 586 (struct sockaddr *)&group, 587 (struct sockaddr *)&udp_in[0]); 588 if (blocked != MCAST_PASS) { 589 if (blocked == MCAST_NOTGMEMBER) 590 IPSTAT_INC(ips_notmember); 591 if (blocked == MCAST_NOTSMEMBER || 592 blocked == MCAST_MUTED) 593 UDPSTAT_INC(udps_filtermcast); 594 INP_RUNLOCK(inp); 595 continue; 596 } 597 } 598 if (last != NULL) { 599 struct mbuf *n; 600 601 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != 602 NULL) { 603 if (proto == IPPROTO_UDPLITE) 604 UDPLITE_PROBE(receive, NULL, last, ip, 605 last, uh); 606 else 607 UDP_PROBE(receive, NULL, last, ip, last, 608 uh); 609 if (udp_append(last, ip, n, iphlen, 610 udp_in)) { 611 goto inp_lost; 612 } 613 } 614 INP_RUNLOCK(last); 615 } 616 last = inp; 617 /* 618 * Don't look for additional matches if this one does 619 * not have either the SO_REUSEPORT or SO_REUSEADDR 620 * socket options set. This heuristic avoids 621 * searching through all pcbs in the common case of a 622 * non-shared port. It assumes that an application 623 * will never clear these options after setting them. 624 */ 625 if ((last->inp_socket->so_options & 626 (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) 627 break; 628 } 629 630 if (last == NULL) { 631 /* 632 * No matching pcb found; discard datagram. (No need 633 * to send an ICMP Port Unreachable for a broadcast 634 * or multicast datgram.) 635 */ 636 UDPSTAT_INC(udps_noportbcast); 637 if (inp) 638 INP_RUNLOCK(inp); 639 goto badunlocked; 640 } 641 if (proto == IPPROTO_UDPLITE) 642 UDPLITE_PROBE(receive, NULL, last, ip, last, uh); 643 else 644 UDP_PROBE(receive, NULL, last, ip, last, uh); 645 if (udp_append(last, ip, m, iphlen, udp_in) == 0) 646 INP_RUNLOCK(last); 647 inp_lost: 648 return (IPPROTO_DONE); 649 } 650 651 /* 652 * Locate pcb for datagram. 653 */ 654 655 /* 656 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. 657 */ 658 if ((m->m_flags & M_IP_NEXTHOP) && 659 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) { 660 struct sockaddr_in *next_hop; 661 662 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 663 664 /* 665 * Transparently forwarded. Pretend to be the destination. 666 * Already got one like this? 667 */ 668 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport, 669 ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m); 670 if (!inp) { 671 /* 672 * It's new. Try to find the ambushing socket. 673 * Because we've rewritten the destination address, 674 * any hardware-generated hash is ignored. 675 */ 676 inp = in_pcblookup(pcbinfo, ip->ip_src, 677 uh->uh_sport, next_hop->sin_addr, 678 next_hop->sin_port ? htons(next_hop->sin_port) : 679 uh->uh_dport, INPLOOKUP_WILDCARD | 680 INPLOOKUP_RLOCKPCB, ifp); 681 } 682 /* Remove the tag from the packet. We don't need it anymore. */ 683 m_tag_delete(m, fwd_tag); 684 m->m_flags &= ~M_IP_NEXTHOP; 685 } else 686 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport, 687 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD | 688 INPLOOKUP_RLOCKPCB, ifp, m); 689 if (inp == NULL) { 690 if (V_udp_log_in_vain) { 691 char src[INET_ADDRSTRLEN]; 692 char dst[INET_ADDRSTRLEN]; 693 694 log(LOG_INFO, 695 "Connection attempt to UDP %s:%d from %s:%d\n", 696 inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport), 697 inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport)); 698 } 699 if (proto == IPPROTO_UDPLITE) 700 UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh); 701 else 702 UDP_PROBE(receive, NULL, NULL, ip, NULL, uh); 703 UDPSTAT_INC(udps_noport); 704 if (m->m_flags & (M_BCAST | M_MCAST)) { 705 UDPSTAT_INC(udps_noportbcast); 706 goto badunlocked; 707 } 708 if (V_udp_blackhole) 709 goto badunlocked; 710 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 711 goto badunlocked; 712 *ip = save_ip; 713 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 714 return (IPPROTO_DONE); 715 } 716 717 /* 718 * Check the minimum TTL for socket. 719 */ 720 INP_RLOCK_ASSERT(inp); 721 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) { 722 if (proto == IPPROTO_UDPLITE) 723 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh); 724 else 725 UDP_PROBE(receive, NULL, inp, ip, inp, uh); 726 INP_RUNLOCK(inp); 727 m_freem(m); 728 return (IPPROTO_DONE); 729 } 730 if (cscov_partial) { 731 struct udpcb *up; 732 733 up = intoudpcb(inp); 734 if (up->u_rxcslen == 0 || up->u_rxcslen > len) { 735 INP_RUNLOCK(inp); 736 m_freem(m); 737 return (IPPROTO_DONE); 738 } 739 } 740 741 if (proto == IPPROTO_UDPLITE) 742 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh); 743 else 744 UDP_PROBE(receive, NULL, inp, ip, inp, uh); 745 if (udp_append(inp, ip, m, iphlen, udp_in) == 0) 746 INP_RUNLOCK(inp); 747 return (IPPROTO_DONE); 748 749 badunlocked: 750 m_freem(m); 751 return (IPPROTO_DONE); 752 } 753 #endif /* INET */ 754 755 /* 756 * Notify a udp user of an asynchronous error; just wake up so that they can 757 * collect error status. 758 */ 759 struct inpcb * 760 udp_notify(struct inpcb *inp, int errno) 761 { 762 763 INP_WLOCK_ASSERT(inp); 764 if ((errno == EHOSTUNREACH || errno == ENETUNREACH || 765 errno == EHOSTDOWN) && inp->inp_route.ro_nh) { 766 NH_FREE(inp->inp_route.ro_nh); 767 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 768 } 769 770 inp->inp_socket->so_error = errno; 771 sorwakeup(inp->inp_socket); 772 sowwakeup(inp->inp_socket); 773 return (inp); 774 } 775 776 #ifdef INET 777 static void 778 udp_common_ctlinput(int cmd, struct sockaddr *sa, void *vip, 779 struct inpcbinfo *pcbinfo) 780 { 781 struct ip *ip = vip; 782 struct udphdr *uh; 783 struct in_addr faddr; 784 struct inpcb *inp; 785 786 faddr = ((struct sockaddr_in *)sa)->sin_addr; 787 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 788 return; 789 790 if (PRC_IS_REDIRECT(cmd)) { 791 /* signal EHOSTDOWN, as it flushes the cached route */ 792 in_pcbnotifyall(&V_udbinfo, faddr, EHOSTDOWN, udp_notify); 793 return; 794 } 795 796 /* 797 * Hostdead is ugly because it goes linearly through all PCBs. 798 * 799 * XXX: We never get this from ICMP, otherwise it makes an excellent 800 * DoS attack on machines with many connections. 801 */ 802 if (cmd == PRC_HOSTDEAD) 803 ip = NULL; 804 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 805 return; 806 if (ip != NULL) { 807 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 808 inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport, 809 ip->ip_src, uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL); 810 if (inp != NULL) { 811 INP_WLOCK_ASSERT(inp); 812 if (inp->inp_socket != NULL) { 813 udp_notify(inp, inetctlerrmap[cmd]); 814 } 815 INP_WUNLOCK(inp); 816 } else { 817 inp = in_pcblookup(pcbinfo, faddr, uh->uh_dport, 818 ip->ip_src, uh->uh_sport, 819 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL); 820 if (inp != NULL) { 821 struct udpcb *up; 822 void *ctx; 823 udp_tun_icmp_t func; 824 825 up = intoudpcb(inp); 826 ctx = up->u_tun_ctx; 827 func = up->u_icmp_func; 828 INP_RUNLOCK(inp); 829 if (func != NULL) 830 (*func)(cmd, sa, vip, ctx); 831 } 832 } 833 } else 834 in_pcbnotifyall(pcbinfo, faddr, inetctlerrmap[cmd], 835 udp_notify); 836 } 837 void 838 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 839 { 840 841 return (udp_common_ctlinput(cmd, sa, vip, &V_udbinfo)); 842 } 843 844 void 845 udplite_ctlinput(int cmd, struct sockaddr *sa, void *vip) 846 { 847 848 return (udp_common_ctlinput(cmd, sa, vip, &V_ulitecbinfo)); 849 } 850 #endif /* INET */ 851 852 static int 853 udp_pcblist(SYSCTL_HANDLER_ARGS) 854 { 855 struct xinpgen xig; 856 struct epoch_tracker et; 857 struct inpcb *inp; 858 int error; 859 860 if (req->newptr != 0) 861 return (EPERM); 862 863 if (req->oldptr == 0) { 864 int n; 865 866 n = V_udbinfo.ipi_count; 867 n += imax(n / 8, 10); 868 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb); 869 return (0); 870 } 871 872 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 873 return (error); 874 875 bzero(&xig, sizeof(xig)); 876 xig.xig_len = sizeof xig; 877 xig.xig_count = V_udbinfo.ipi_count; 878 xig.xig_gen = V_udbinfo.ipi_gencnt; 879 xig.xig_sogen = so_gencnt; 880 error = SYSCTL_OUT(req, &xig, sizeof xig); 881 if (error) 882 return (error); 883 884 NET_EPOCH_ENTER(et); 885 for (inp = CK_LIST_FIRST(V_udbinfo.ipi_listhead); 886 inp != NULL; 887 inp = CK_LIST_NEXT(inp, inp_list)) { 888 INP_RLOCK(inp); 889 if (inp->inp_gencnt <= xig.xig_gen && 890 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 891 struct xinpcb xi; 892 893 in_pcbtoxinpcb(inp, &xi); 894 INP_RUNLOCK(inp); 895 error = SYSCTL_OUT(req, &xi, sizeof xi); 896 if (error) 897 break; 898 } else 899 INP_RUNLOCK(inp); 900 } 901 NET_EPOCH_EXIT(et); 902 903 if (!error) { 904 /* 905 * Give the user an updated idea of our state. If the 906 * generation differs from what we told her before, she knows 907 * that something happened while we were processing this 908 * request, and it might be necessary to retry. 909 */ 910 xig.xig_gen = V_udbinfo.ipi_gencnt; 911 xig.xig_sogen = so_gencnt; 912 xig.xig_count = V_udbinfo.ipi_count; 913 error = SYSCTL_OUT(req, &xig, sizeof xig); 914 } 915 916 return (error); 917 } 918 919 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, 920 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 921 udp_pcblist, "S,xinpcb", 922 "List of active UDP sockets"); 923 924 #ifdef INET 925 static int 926 udp_getcred(SYSCTL_HANDLER_ARGS) 927 { 928 struct xucred xuc; 929 struct sockaddr_in addrs[2]; 930 struct epoch_tracker et; 931 struct inpcb *inp; 932 int error; 933 934 error = priv_check(req->td, PRIV_NETINET_GETCRED); 935 if (error) 936 return (error); 937 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 938 if (error) 939 return (error); 940 NET_EPOCH_ENTER(et); 941 inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 942 addrs[0].sin_addr, addrs[0].sin_port, 943 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL); 944 NET_EPOCH_EXIT(et); 945 if (inp != NULL) { 946 INP_RLOCK_ASSERT(inp); 947 if (inp->inp_socket == NULL) 948 error = ENOENT; 949 if (error == 0) 950 error = cr_canseeinpcb(req->td->td_ucred, inp); 951 if (error == 0) 952 cru2x(inp->inp_cred, &xuc); 953 INP_RUNLOCK(inp); 954 } else 955 error = ENOENT; 956 if (error == 0) 957 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 958 return (error); 959 } 960 961 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 962 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE, 963 0, 0, udp_getcred, "S,xucred", 964 "Get the xucred of a UDP connection"); 965 #endif /* INET */ 966 967 int 968 udp_ctloutput(struct socket *so, struct sockopt *sopt) 969 { 970 struct inpcb *inp; 971 struct udpcb *up; 972 int isudplite, error, optval; 973 974 error = 0; 975 isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0; 976 inp = sotoinpcb(so); 977 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 978 INP_WLOCK(inp); 979 if (sopt->sopt_level != so->so_proto->pr_protocol) { 980 #ifdef INET6 981 if (INP_CHECK_SOCKAF(so, AF_INET6)) { 982 INP_WUNLOCK(inp); 983 error = ip6_ctloutput(so, sopt); 984 } 985 #endif 986 #if defined(INET) && defined(INET6) 987 else 988 #endif 989 #ifdef INET 990 { 991 INP_WUNLOCK(inp); 992 error = ip_ctloutput(so, sopt); 993 } 994 #endif 995 return (error); 996 } 997 998 switch (sopt->sopt_dir) { 999 case SOPT_SET: 1000 switch (sopt->sopt_name) { 1001 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 1002 #ifdef INET 1003 case UDP_ENCAP: 1004 if (!IPSEC_ENABLED(ipv4)) { 1005 INP_WUNLOCK(inp); 1006 return (ENOPROTOOPT); 1007 } 1008 error = UDPENCAP_PCBCTL(inp, sopt); 1009 break; 1010 #endif /* INET */ 1011 #endif /* IPSEC */ 1012 case UDPLITE_SEND_CSCOV: 1013 case UDPLITE_RECV_CSCOV: 1014 if (!isudplite) { 1015 INP_WUNLOCK(inp); 1016 error = ENOPROTOOPT; 1017 break; 1018 } 1019 INP_WUNLOCK(inp); 1020 error = sooptcopyin(sopt, &optval, sizeof(optval), 1021 sizeof(optval)); 1022 if (error != 0) 1023 break; 1024 inp = sotoinpcb(so); 1025 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 1026 INP_WLOCK(inp); 1027 up = intoudpcb(inp); 1028 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 1029 if ((optval != 0 && optval < 8) || (optval > 65535)) { 1030 INP_WUNLOCK(inp); 1031 error = EINVAL; 1032 break; 1033 } 1034 if (sopt->sopt_name == UDPLITE_SEND_CSCOV) 1035 up->u_txcslen = optval; 1036 else 1037 up->u_rxcslen = optval; 1038 INP_WUNLOCK(inp); 1039 break; 1040 default: 1041 INP_WUNLOCK(inp); 1042 error = ENOPROTOOPT; 1043 break; 1044 } 1045 break; 1046 case SOPT_GET: 1047 switch (sopt->sopt_name) { 1048 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 1049 #ifdef INET 1050 case UDP_ENCAP: 1051 if (!IPSEC_ENABLED(ipv4)) { 1052 INP_WUNLOCK(inp); 1053 return (ENOPROTOOPT); 1054 } 1055 error = UDPENCAP_PCBCTL(inp, sopt); 1056 break; 1057 #endif /* INET */ 1058 #endif /* IPSEC */ 1059 case UDPLITE_SEND_CSCOV: 1060 case UDPLITE_RECV_CSCOV: 1061 if (!isudplite) { 1062 INP_WUNLOCK(inp); 1063 error = ENOPROTOOPT; 1064 break; 1065 } 1066 up = intoudpcb(inp); 1067 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 1068 if (sopt->sopt_name == UDPLITE_SEND_CSCOV) 1069 optval = up->u_txcslen; 1070 else 1071 optval = up->u_rxcslen; 1072 INP_WUNLOCK(inp); 1073 error = sooptcopyout(sopt, &optval, sizeof(optval)); 1074 break; 1075 default: 1076 INP_WUNLOCK(inp); 1077 error = ENOPROTOOPT; 1078 break; 1079 } 1080 break; 1081 } 1082 return (error); 1083 } 1084 1085 #ifdef INET 1086 #ifdef INET6 1087 /* The logic here is derived from ip6_setpktopt(). See comments there. */ 1088 static int 1089 udp_v4mapped_pktinfo(struct cmsghdr *cm, struct sockaddr_in * src, 1090 struct inpcb *inp, int flags) 1091 { 1092 struct ifnet *ifp; 1093 struct in6_pktinfo *pktinfo; 1094 struct in_addr ia; 1095 1096 if ((flags & PRUS_IPV6) == 0) 1097 return (0); 1098 1099 if (cm->cmsg_level != IPPROTO_IPV6) 1100 return (0); 1101 1102 if (cm->cmsg_type != IPV6_2292PKTINFO && 1103 cm->cmsg_type != IPV6_PKTINFO) 1104 return (0); 1105 1106 if (cm->cmsg_len != 1107 CMSG_LEN(sizeof(struct in6_pktinfo))) 1108 return (EINVAL); 1109 1110 pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm); 1111 if (!IN6_IS_ADDR_V4MAPPED(&pktinfo->ipi6_addr) && 1112 !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) 1113 return (EINVAL); 1114 1115 /* Validate the interface index if specified. */ 1116 if (pktinfo->ipi6_ifindex > V_if_index) 1117 return (ENXIO); 1118 1119 ifp = NULL; 1120 if (pktinfo->ipi6_ifindex) { 1121 ifp = ifnet_byindex(pktinfo->ipi6_ifindex); 1122 if (ifp == NULL) 1123 return (ENXIO); 1124 } 1125 if (ifp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 1126 ia.s_addr = pktinfo->ipi6_addr.s6_addr32[3]; 1127 if (in_ifhasaddr(ifp, ia) == 0) 1128 return (EADDRNOTAVAIL); 1129 } 1130 1131 bzero(src, sizeof(*src)); 1132 src->sin_family = AF_INET; 1133 src->sin_len = sizeof(*src); 1134 src->sin_port = inp->inp_lport; 1135 src->sin_addr.s_addr = pktinfo->ipi6_addr.s6_addr32[3]; 1136 1137 return (0); 1138 } 1139 #endif 1140 1141 static int 1142 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr, 1143 struct mbuf *control, struct thread *td, int flags) 1144 { 1145 struct udpiphdr *ui; 1146 int len = m->m_pkthdr.len; 1147 struct in_addr faddr, laddr; 1148 struct cmsghdr *cm; 1149 struct inpcbinfo *pcbinfo; 1150 struct sockaddr_in *sin, src; 1151 struct epoch_tracker et; 1152 int cscov_partial = 0; 1153 int error = 0; 1154 int ipflags; 1155 u_short fport, lport; 1156 u_char tos; 1157 uint8_t pr; 1158 uint16_t cscov = 0; 1159 uint32_t flowid = 0; 1160 uint8_t flowtype = M_HASHTYPE_NONE; 1161 1162 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 1163 if (control) 1164 m_freem(control); 1165 m_freem(m); 1166 return (EMSGSIZE); 1167 } 1168 1169 src.sin_family = 0; 1170 sin = (struct sockaddr_in *)addr; 1171 1172 /* 1173 * udp_output() may need to temporarily bind or connect the current 1174 * inpcb. As such, we don't know up front whether we will need the 1175 * pcbinfo lock or not. Do any work to decide what is needed up 1176 * front before acquiring any locks. 1177 * 1178 * We will need network epoch in either case, to safely lookup into 1179 * pcb hash. 1180 */ 1181 if (sin == NULL || 1182 (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0)) 1183 INP_WLOCK(inp); 1184 else 1185 INP_RLOCK(inp); 1186 NET_EPOCH_ENTER(et); 1187 tos = inp->inp_ip_tos; 1188 if (control != NULL) { 1189 /* 1190 * XXX: Currently, we assume all the optional information is 1191 * stored in a single mbuf. 1192 */ 1193 if (control->m_next) { 1194 m_freem(control); 1195 error = EINVAL; 1196 goto release; 1197 } 1198 for (; control->m_len > 0; 1199 control->m_data += CMSG_ALIGN(cm->cmsg_len), 1200 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 1201 cm = mtod(control, struct cmsghdr *); 1202 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 1203 || cm->cmsg_len > control->m_len) { 1204 error = EINVAL; 1205 break; 1206 } 1207 #ifdef INET6 1208 error = udp_v4mapped_pktinfo(cm, &src, inp, flags); 1209 if (error != 0) 1210 break; 1211 #endif 1212 if (cm->cmsg_level != IPPROTO_IP) 1213 continue; 1214 1215 switch (cm->cmsg_type) { 1216 case IP_SENDSRCADDR: 1217 if (cm->cmsg_len != 1218 CMSG_LEN(sizeof(struct in_addr))) { 1219 error = EINVAL; 1220 break; 1221 } 1222 bzero(&src, sizeof(src)); 1223 src.sin_family = AF_INET; 1224 src.sin_len = sizeof(src); 1225 src.sin_port = inp->inp_lport; 1226 src.sin_addr = 1227 *(struct in_addr *)CMSG_DATA(cm); 1228 break; 1229 1230 case IP_TOS: 1231 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) { 1232 error = EINVAL; 1233 break; 1234 } 1235 tos = *(u_char *)CMSG_DATA(cm); 1236 break; 1237 1238 case IP_FLOWID: 1239 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) { 1240 error = EINVAL; 1241 break; 1242 } 1243 flowid = *(uint32_t *) CMSG_DATA(cm); 1244 break; 1245 1246 case IP_FLOWTYPE: 1247 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) { 1248 error = EINVAL; 1249 break; 1250 } 1251 flowtype = *(uint32_t *) CMSG_DATA(cm); 1252 break; 1253 1254 #ifdef RSS 1255 case IP_RSSBUCKETID: 1256 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) { 1257 error = EINVAL; 1258 break; 1259 } 1260 /* This is just a placeholder for now */ 1261 break; 1262 #endif /* RSS */ 1263 default: 1264 error = ENOPROTOOPT; 1265 break; 1266 } 1267 if (error) 1268 break; 1269 } 1270 m_freem(control); 1271 } 1272 if (error) 1273 goto release; 1274 1275 pr = inp->inp_socket->so_proto->pr_protocol; 1276 pcbinfo = udp_get_inpcbinfo(pr); 1277 1278 /* 1279 * If the IP_SENDSRCADDR control message was specified, override the 1280 * source address for this datagram. Its use is invalidated if the 1281 * address thus specified is incomplete or clobbers other inpcbs. 1282 */ 1283 laddr = inp->inp_laddr; 1284 lport = inp->inp_lport; 1285 if (src.sin_family == AF_INET) { 1286 INP_HASH_LOCK_ASSERT(pcbinfo); 1287 if ((lport == 0) || 1288 (laddr.s_addr == INADDR_ANY && 1289 src.sin_addr.s_addr == INADDR_ANY)) { 1290 error = EINVAL; 1291 goto release; 1292 } 1293 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 1294 &laddr.s_addr, &lport, td->td_ucred); 1295 if (error) 1296 goto release; 1297 } 1298 1299 /* 1300 * If a UDP socket has been connected, then a local address/port will 1301 * have been selected and bound. 1302 * 1303 * If a UDP socket has not been connected to, then an explicit 1304 * destination address must be used, in which case a local 1305 * address/port may not have been selected and bound. 1306 */ 1307 if (sin != NULL) { 1308 INP_LOCK_ASSERT(inp); 1309 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1310 error = EISCONN; 1311 goto release; 1312 } 1313 1314 /* 1315 * Jail may rewrite the destination address, so let it do 1316 * that before we use it. 1317 */ 1318 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1319 if (error) 1320 goto release; 1321 1322 /* 1323 * If a local address or port hasn't yet been selected, or if 1324 * the destination address needs to be rewritten due to using 1325 * a special INADDR_ constant, invoke in_pcbconnect_setup() 1326 * to do the heavy lifting. Once a port is selected, we 1327 * commit the binding back to the socket; we also commit the 1328 * binding of the address if in jail. 1329 * 1330 * If we already have a valid binding and we're not 1331 * requesting a destination address rewrite, use a fast path. 1332 */ 1333 if (inp->inp_laddr.s_addr == INADDR_ANY || 1334 inp->inp_lport == 0 || 1335 sin->sin_addr.s_addr == INADDR_ANY || 1336 sin->sin_addr.s_addr == INADDR_BROADCAST) { 1337 INP_HASH_LOCK_ASSERT(pcbinfo); 1338 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, 1339 &lport, &faddr.s_addr, &fport, NULL, 1340 td->td_ucred); 1341 if (error) 1342 goto release; 1343 1344 /* 1345 * XXXRW: Why not commit the port if the address is 1346 * !INADDR_ANY? 1347 */ 1348 /* Commit the local port if newly assigned. */ 1349 if (inp->inp_laddr.s_addr == INADDR_ANY && 1350 inp->inp_lport == 0) { 1351 INP_WLOCK_ASSERT(inp); 1352 /* 1353 * Remember addr if jailed, to prevent 1354 * rebinding. 1355 */ 1356 if (prison_flag(td->td_ucred, PR_IP4)) 1357 inp->inp_laddr = laddr; 1358 inp->inp_lport = lport; 1359 INP_HASH_WLOCK(pcbinfo); 1360 error = in_pcbinshash(inp); 1361 INP_HASH_WUNLOCK(pcbinfo); 1362 if (error != 0) { 1363 inp->inp_lport = 0; 1364 error = EAGAIN; 1365 goto release; 1366 } 1367 inp->inp_flags |= INP_ANONPORT; 1368 } 1369 } else { 1370 faddr = sin->sin_addr; 1371 fport = sin->sin_port; 1372 } 1373 } else { 1374 INP_LOCK_ASSERT(inp); 1375 faddr = inp->inp_faddr; 1376 fport = inp->inp_fport; 1377 if (faddr.s_addr == INADDR_ANY) { 1378 error = ENOTCONN; 1379 goto release; 1380 } 1381 } 1382 1383 /* 1384 * Calculate data length and get a mbuf for UDP, IP, and possible 1385 * link-layer headers. Immediate slide the data pointer back forward 1386 * since we won't use that space at this layer. 1387 */ 1388 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT); 1389 if (m == NULL) { 1390 error = ENOBUFS; 1391 goto release; 1392 } 1393 m->m_data += max_linkhdr; 1394 m->m_len -= max_linkhdr; 1395 m->m_pkthdr.len -= max_linkhdr; 1396 1397 /* 1398 * Fill in mbuf with extended UDP header and addresses and length put 1399 * into network format. 1400 */ 1401 ui = mtod(m, struct udpiphdr *); 1402 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 1403 ui->ui_v = IPVERSION << 4; 1404 ui->ui_pr = pr; 1405 ui->ui_src = laddr; 1406 ui->ui_dst = faddr; 1407 ui->ui_sport = lport; 1408 ui->ui_dport = fport; 1409 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 1410 if (pr == IPPROTO_UDPLITE) { 1411 struct udpcb *up; 1412 uint16_t plen; 1413 1414 up = intoudpcb(inp); 1415 cscov = up->u_txcslen; 1416 plen = (u_short)len + sizeof(struct udphdr); 1417 if (cscov >= plen) 1418 cscov = 0; 1419 ui->ui_len = htons(plen); 1420 ui->ui_ulen = htons(cscov); 1421 /* 1422 * For UDP-Lite, checksum coverage length of zero means 1423 * the entire UDPLite packet is covered by the checksum. 1424 */ 1425 cscov_partial = (cscov == 0) ? 0 : 1; 1426 } 1427 1428 /* 1429 * Set the Don't Fragment bit in the IP header. 1430 */ 1431 if (inp->inp_flags & INP_DONTFRAG) { 1432 struct ip *ip; 1433 1434 ip = (struct ip *)&ui->ui_i; 1435 ip->ip_off |= htons(IP_DF); 1436 } 1437 1438 ipflags = 0; 1439 if (inp->inp_socket->so_options & SO_DONTROUTE) 1440 ipflags |= IP_ROUTETOIF; 1441 if (inp->inp_socket->so_options & SO_BROADCAST) 1442 ipflags |= IP_ALLOWBROADCAST; 1443 if (inp->inp_flags & INP_ONESBCAST) 1444 ipflags |= IP_SENDONES; 1445 1446 #ifdef MAC 1447 mac_inpcb_create_mbuf(inp, m); 1448 #endif 1449 1450 /* 1451 * Set up checksum and output datagram. 1452 */ 1453 ui->ui_sum = 0; 1454 if (pr == IPPROTO_UDPLITE) { 1455 if (inp->inp_flags & INP_ONESBCAST) 1456 faddr.s_addr = INADDR_BROADCAST; 1457 if (cscov_partial) { 1458 if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0) 1459 ui->ui_sum = 0xffff; 1460 } else { 1461 if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0) 1462 ui->ui_sum = 0xffff; 1463 } 1464 } else if (V_udp_cksum) { 1465 if (inp->inp_flags & INP_ONESBCAST) 1466 faddr.s_addr = INADDR_BROADCAST; 1467 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 1468 htons((u_short)len + sizeof(struct udphdr) + pr)); 1469 m->m_pkthdr.csum_flags = CSUM_UDP; 1470 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 1471 } 1472 ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len); 1473 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 1474 ((struct ip *)ui)->ip_tos = tos; /* XXX */ 1475 UDPSTAT_INC(udps_opackets); 1476 1477 /* 1478 * Setup flowid / RSS information for outbound socket. 1479 * 1480 * Once the UDP code decides to set a flowid some other way, 1481 * this allows the flowid to be overridden by userland. 1482 */ 1483 if (flowtype != M_HASHTYPE_NONE) { 1484 m->m_pkthdr.flowid = flowid; 1485 M_HASHTYPE_SET(m, flowtype); 1486 } 1487 #ifdef RSS 1488 else { 1489 uint32_t hash_val, hash_type; 1490 /* 1491 * Calculate an appropriate RSS hash for UDP and 1492 * UDP Lite. 1493 * 1494 * The called function will take care of figuring out 1495 * whether a 2-tuple or 4-tuple hash is required based 1496 * on the currently configured scheme. 1497 * 1498 * Later later on connected socket values should be 1499 * cached in the inpcb and reused, rather than constantly 1500 * re-calculating it. 1501 * 1502 * UDP Lite is a different protocol number and will 1503 * likely end up being hashed as a 2-tuple until 1504 * RSS / NICs grow UDP Lite protocol awareness. 1505 */ 1506 if (rss_proto_software_hash_v4(faddr, laddr, fport, lport, 1507 pr, &hash_val, &hash_type) == 0) { 1508 m->m_pkthdr.flowid = hash_val; 1509 M_HASHTYPE_SET(m, hash_type); 1510 } 1511 } 1512 1513 /* 1514 * Don't override with the inp cached flowid value. 1515 * 1516 * Depending upon the kind of send being done, the inp 1517 * flowid/flowtype values may actually not be appropriate 1518 * for this particular socket send. 1519 * 1520 * We should either leave the flowid at zero (which is what is 1521 * currently done) or set it to some software generated 1522 * hash value based on the packet contents. 1523 */ 1524 ipflags |= IP_NODEFAULTFLOWID; 1525 #endif /* RSS */ 1526 1527 if (pr == IPPROTO_UDPLITE) 1528 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u); 1529 else 1530 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u); 1531 error = ip_output(m, inp->inp_options, 1532 INP_WLOCKED(inp) ? &inp->inp_route : NULL, ipflags, 1533 inp->inp_moptions, inp); 1534 INP_UNLOCK(inp); 1535 NET_EPOCH_EXIT(et); 1536 return (error); 1537 1538 release: 1539 INP_UNLOCK(inp); 1540 NET_EPOCH_EXIT(et); 1541 m_freem(m); 1542 return (error); 1543 } 1544 1545 static void 1546 udp_abort(struct socket *so) 1547 { 1548 struct inpcb *inp; 1549 struct inpcbinfo *pcbinfo; 1550 1551 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1552 inp = sotoinpcb(so); 1553 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 1554 INP_WLOCK(inp); 1555 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1556 INP_HASH_WLOCK(pcbinfo); 1557 in_pcbdisconnect(inp); 1558 inp->inp_laddr.s_addr = INADDR_ANY; 1559 INP_HASH_WUNLOCK(pcbinfo); 1560 soisdisconnected(so); 1561 } 1562 INP_WUNLOCK(inp); 1563 } 1564 1565 static int 1566 udp_attach(struct socket *so, int proto, struct thread *td) 1567 { 1568 static uint32_t udp_flowid; 1569 struct inpcb *inp; 1570 struct inpcbinfo *pcbinfo; 1571 int error; 1572 1573 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1574 inp = sotoinpcb(so); 1575 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 1576 error = soreserve(so, udp_sendspace, udp_recvspace); 1577 if (error) 1578 return (error); 1579 INP_INFO_WLOCK(pcbinfo); 1580 error = in_pcballoc(so, pcbinfo); 1581 if (error) { 1582 INP_INFO_WUNLOCK(pcbinfo); 1583 return (error); 1584 } 1585 1586 inp = sotoinpcb(so); 1587 inp->inp_vflag |= INP_IPV4; 1588 inp->inp_ip_ttl = V_ip_defttl; 1589 inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1); 1590 inp->inp_flowtype = M_HASHTYPE_OPAQUE; 1591 1592 error = udp_newudpcb(inp); 1593 if (error) { 1594 in_pcbdetach(inp); 1595 in_pcbfree(inp); 1596 INP_INFO_WUNLOCK(pcbinfo); 1597 return (error); 1598 } 1599 1600 INP_WUNLOCK(inp); 1601 INP_INFO_WUNLOCK(pcbinfo); 1602 return (0); 1603 } 1604 #endif /* INET */ 1605 1606 int 1607 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx) 1608 { 1609 struct inpcb *inp; 1610 struct udpcb *up; 1611 1612 KASSERT(so->so_type == SOCK_DGRAM, 1613 ("udp_set_kernel_tunneling: !dgram")); 1614 inp = sotoinpcb(so); 1615 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL")); 1616 INP_WLOCK(inp); 1617 up = intoudpcb(inp); 1618 if ((up->u_tun_func != NULL) || 1619 (up->u_icmp_func != NULL)) { 1620 INP_WUNLOCK(inp); 1621 return (EBUSY); 1622 } 1623 up->u_tun_func = f; 1624 up->u_icmp_func = i; 1625 up->u_tun_ctx = ctx; 1626 INP_WUNLOCK(inp); 1627 return (0); 1628 } 1629 1630 #ifdef INET 1631 static int 1632 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1633 { 1634 struct inpcb *inp; 1635 struct inpcbinfo *pcbinfo; 1636 int error; 1637 1638 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1639 inp = sotoinpcb(so); 1640 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1641 INP_WLOCK(inp); 1642 INP_HASH_WLOCK(pcbinfo); 1643 error = in_pcbbind(inp, nam, td->td_ucred); 1644 INP_HASH_WUNLOCK(pcbinfo); 1645 INP_WUNLOCK(inp); 1646 return (error); 1647 } 1648 1649 static void 1650 udp_close(struct socket *so) 1651 { 1652 struct inpcb *inp; 1653 struct inpcbinfo *pcbinfo; 1654 1655 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1656 inp = sotoinpcb(so); 1657 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1658 INP_WLOCK(inp); 1659 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1660 INP_HASH_WLOCK(pcbinfo); 1661 in_pcbdisconnect(inp); 1662 inp->inp_laddr.s_addr = INADDR_ANY; 1663 INP_HASH_WUNLOCK(pcbinfo); 1664 soisdisconnected(so); 1665 } 1666 INP_WUNLOCK(inp); 1667 } 1668 1669 static int 1670 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1671 { 1672 struct epoch_tracker et; 1673 struct inpcb *inp; 1674 struct inpcbinfo *pcbinfo; 1675 struct sockaddr_in *sin; 1676 int error; 1677 1678 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1679 inp = sotoinpcb(so); 1680 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1681 INP_WLOCK(inp); 1682 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1683 INP_WUNLOCK(inp); 1684 return (EISCONN); 1685 } 1686 sin = (struct sockaddr_in *)nam; 1687 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1688 if (error != 0) { 1689 INP_WUNLOCK(inp); 1690 return (error); 1691 } 1692 NET_EPOCH_ENTER(et); 1693 INP_HASH_WLOCK(pcbinfo); 1694 error = in_pcbconnect(inp, nam, td->td_ucred); 1695 INP_HASH_WUNLOCK(pcbinfo); 1696 NET_EPOCH_EXIT(et); 1697 if (error == 0) 1698 soisconnected(so); 1699 INP_WUNLOCK(inp); 1700 return (error); 1701 } 1702 1703 static void 1704 udp_detach(struct socket *so) 1705 { 1706 struct inpcb *inp; 1707 struct inpcbinfo *pcbinfo; 1708 struct udpcb *up; 1709 1710 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1711 inp = sotoinpcb(so); 1712 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1713 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY, 1714 ("udp_detach: not disconnected")); 1715 INP_INFO_WLOCK(pcbinfo); 1716 INP_WLOCK(inp); 1717 up = intoudpcb(inp); 1718 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 1719 inp->inp_ppcb = NULL; 1720 in_pcbdetach(inp); 1721 in_pcbfree(inp); 1722 INP_INFO_WUNLOCK(pcbinfo); 1723 udp_discardcb(up); 1724 } 1725 1726 static int 1727 udp_disconnect(struct socket *so) 1728 { 1729 struct inpcb *inp; 1730 struct inpcbinfo *pcbinfo; 1731 1732 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1733 inp = sotoinpcb(so); 1734 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1735 INP_WLOCK(inp); 1736 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1737 INP_WUNLOCK(inp); 1738 return (ENOTCONN); 1739 } 1740 INP_HASH_WLOCK(pcbinfo); 1741 in_pcbdisconnect(inp); 1742 inp->inp_laddr.s_addr = INADDR_ANY; 1743 INP_HASH_WUNLOCK(pcbinfo); 1744 SOCK_LOCK(so); 1745 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1746 SOCK_UNLOCK(so); 1747 INP_WUNLOCK(inp); 1748 return (0); 1749 } 1750 1751 static int 1752 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1753 struct mbuf *control, struct thread *td) 1754 { 1755 struct inpcb *inp; 1756 1757 inp = sotoinpcb(so); 1758 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1759 return (udp_output(inp, m, addr, control, td, flags)); 1760 } 1761 #endif /* INET */ 1762 1763 int 1764 udp_shutdown(struct socket *so) 1765 { 1766 struct inpcb *inp; 1767 1768 inp = sotoinpcb(so); 1769 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1770 INP_WLOCK(inp); 1771 socantsendmore(so); 1772 INP_WUNLOCK(inp); 1773 return (0); 1774 } 1775 1776 #ifdef INET 1777 struct pr_usrreqs udp_usrreqs = { 1778 .pru_abort = udp_abort, 1779 .pru_attach = udp_attach, 1780 .pru_bind = udp_bind, 1781 .pru_connect = udp_connect, 1782 .pru_control = in_control, 1783 .pru_detach = udp_detach, 1784 .pru_disconnect = udp_disconnect, 1785 .pru_peeraddr = in_getpeeraddr, 1786 .pru_send = udp_send, 1787 .pru_soreceive = soreceive_dgram, 1788 .pru_sosend = sosend_dgram, 1789 .pru_shutdown = udp_shutdown, 1790 .pru_sockaddr = in_getsockaddr, 1791 .pru_sosetlabel = in_pcbsosetlabel, 1792 .pru_close = udp_close, 1793 }; 1794 #endif /* INET */ 1795