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 39 #include <sys/cdefs.h> 40 #include "opt_inet.h" 41 #include "opt_inet6.h" 42 #include "opt_ipsec.h" 43 #include "opt_route.h" 44 #include "opt_rss.h" 45 46 #include <sys/param.h> 47 #include <sys/domain.h> 48 #include <sys/eventhandler.h> 49 #include <sys/jail.h> 50 #include <sys/kernel.h> 51 #include <sys/lock.h> 52 #include <sys/malloc.h> 53 #include <sys/mbuf.h> 54 #include <sys/priv.h> 55 #include <sys/proc.h> 56 #include <sys/protosw.h> 57 #include <sys/sdt.h> 58 #include <sys/signalvar.h> 59 #include <sys/socket.h> 60 #include <sys/socketvar.h> 61 #include <sys/sx.h> 62 #include <sys/sysctl.h> 63 #include <sys/syslog.h> 64 #include <sys/systm.h> 65 66 #include <vm/uma.h> 67 68 #include <net/if.h> 69 #include <net/if_var.h> 70 #include <net/route.h> 71 #include <net/route/nhop.h> 72 #include <net/rss_config.h> 73 74 #include <netinet/in.h> 75 #include <netinet/in_kdtrace.h> 76 #include <netinet/in_fib.h> 77 #include <netinet/in_pcb.h> 78 #include <netinet/in_systm.h> 79 #include <netinet/in_var.h> 80 #include <netinet/ip.h> 81 #ifdef INET6 82 #include <netinet/ip6.h> 83 #endif 84 #include <netinet/ip_icmp.h> 85 #include <netinet/icmp_var.h> 86 #include <netinet/ip_var.h> 87 #include <netinet/ip_options.h> 88 #ifdef INET6 89 #include <netinet6/ip6_var.h> 90 #endif 91 #include <netinet/udp.h> 92 #include <netinet/udp_var.h> 93 #include <netinet/udplite.h> 94 #include <netinet/in_rss.h> 95 96 #include <netipsec/ipsec_support.h> 97 98 #include <machine/in_cksum.h> 99 100 #include <security/mac/mac_framework.h> 101 102 /* 103 * UDP and UDP-Lite protocols implementation. 104 * Per RFC 768, August, 1980. 105 * Per RFC 3828, July, 2004. 106 */ 107 108 /* 109 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums 110 * removes the only data integrity mechanism for packets and malformed 111 * packets that would otherwise be discarded due to bad checksums, and may 112 * cause problems (especially for NFS data blocks). 113 */ 114 VNET_DEFINE(int, udp_cksum) = 1; 115 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_VNET | CTLFLAG_RW, 116 &VNET_NAME(udp_cksum), 0, "compute udp checksum"); 117 118 VNET_DEFINE(int, udp_log_in_vain) = 0; 119 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_VNET | CTLFLAG_RW, 120 &VNET_NAME(udp_log_in_vain), 0, "Log all incoming UDP packets"); 121 122 VNET_DEFINE(int, udp_blackhole) = 0; 123 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_VNET | CTLFLAG_RW, 124 &VNET_NAME(udp_blackhole), 0, 125 "Do not send port unreachables for refused connects"); 126 VNET_DEFINE(bool, udp_blackhole_local) = false; 127 SYSCTL_BOOL(_net_inet_udp, OID_AUTO, blackhole_local, CTLFLAG_VNET | 128 CTLFLAG_RW, &VNET_NAME(udp_blackhole_local), false, 129 "Enforce net.inet.udp.blackhole for locally originated packets"); 130 131 u_long udp_sendspace = 9216; /* really max datagram size */ 132 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 133 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 134 135 u_long udp_recvspace = 40 * (1024 + 136 #ifdef INET6 137 sizeof(struct sockaddr_in6) 138 #else 139 sizeof(struct sockaddr_in) 140 #endif 141 ); /* 40 1K datagrams */ 142 143 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 144 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 145 146 VNET_DEFINE(struct inpcbinfo, udbinfo); 147 VNET_DEFINE(struct inpcbinfo, ulitecbinfo); 148 149 #ifndef UDBHASHSIZE 150 #define UDBHASHSIZE 128 151 #endif 152 153 VNET_PCPUSTAT_DEFINE(struct udpstat, udpstat); /* from udp_var.h */ 154 VNET_PCPUSTAT_SYSINIT(udpstat); 155 SYSCTL_VNET_PCPUSTAT(_net_inet_udp, UDPCTL_STATS, stats, struct udpstat, 156 udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)"); 157 158 #ifdef VIMAGE 159 VNET_PCPUSTAT_SYSUNINIT(udpstat); 160 #endif /* VIMAGE */ 161 #ifdef INET 162 static void udp_detach(struct socket *so); 163 #endif 164 165 INPCBSTORAGE_DEFINE(udpcbstor, udpcb, "udpinp", "udp_inpcb", "udp", "udphash"); 166 INPCBSTORAGE_DEFINE(udplitecbstor, udpcb, "udpliteinp", "udplite_inpcb", 167 "udplite", "udplitehash"); 168 169 static void 170 udp_vnet_init(void *arg __unused) 171 { 172 173 /* 174 * For now default to 2-tuple UDP hashing - until the fragment 175 * reassembly code can also update the flowid. 176 * 177 * Once we can calculate the flowid that way and re-establish 178 * a 4-tuple, flip this to 4-tuple. 179 */ 180 in_pcbinfo_init(&V_udbinfo, &udpcbstor, UDBHASHSIZE, UDBHASHSIZE); 181 /* Additional pcbinfo for UDP-Lite */ 182 in_pcbinfo_init(&V_ulitecbinfo, &udplitecbstor, UDBHASHSIZE, 183 UDBHASHSIZE); 184 } 185 VNET_SYSINIT(udp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, 186 udp_vnet_init, NULL); 187 188 /* 189 * Kernel module interface for updating udpstat. The argument is an index 190 * into udpstat treated as an array of u_long. While this encodes the 191 * general layout of udpstat into the caller, it doesn't encode its location, 192 * so that future changes to add, for example, per-CPU stats support won't 193 * cause binary compatibility problems for kernel modules. 194 */ 195 void 196 kmod_udpstat_inc(int statnum) 197 { 198 199 counter_u64_add(VNET(udpstat)[statnum], 1); 200 } 201 202 #ifdef VIMAGE 203 static void 204 udp_destroy(void *unused __unused) 205 { 206 207 in_pcbinfo_destroy(&V_udbinfo); 208 in_pcbinfo_destroy(&V_ulitecbinfo); 209 } 210 VNET_SYSUNINIT(udp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, udp_destroy, NULL); 211 #endif 212 213 #ifdef INET 214 /* 215 * Subroutine of udp_input(), which appends the provided mbuf chain to the 216 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 217 * contains the source address. If the socket ends up being an IPv6 socket, 218 * udp_append() will convert to a sockaddr_in6 before passing the address 219 * into the socket code. 220 * 221 * In the normal case udp_append() will return 0, indicating that you 222 * must unlock the inp. However if a tunneling protocol is in place we increment 223 * the inpcb refcnt and unlock the inp, on return from the tunneling protocol we 224 * then decrement the reference count. If the inp_rele returns 1, indicating the 225 * inp is gone, we return that to the caller to tell them *not* to unlock 226 * the inp. In the case of multi-cast this will cause the distribution 227 * to stop (though most tunneling protocols known currently do *not* use 228 * multicast). 229 */ 230 static int 231 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off, 232 struct sockaddr_in *udp_in) 233 { 234 struct sockaddr *append_sa; 235 struct socket *so; 236 struct mbuf *tmpopts, *opts = NULL; 237 #ifdef INET6 238 struct sockaddr_in6 udp_in6; 239 #endif 240 struct udpcb *up; 241 bool filtered; 242 243 INP_LOCK_ASSERT(inp); 244 245 /* 246 * Engage the tunneling protocol. 247 */ 248 up = intoudpcb(inp); 249 if (up->u_tun_func != NULL) { 250 in_pcbref(inp); 251 INP_RUNLOCK(inp); 252 filtered = (*up->u_tun_func)(n, off, inp, (struct sockaddr *)&udp_in[0], 253 up->u_tun_ctx); 254 INP_RLOCK(inp); 255 if (filtered) 256 return (in_pcbrele_rlocked(inp)); 257 } 258 259 off += sizeof(struct udphdr); 260 261 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 262 /* Check AH/ESP integrity. */ 263 if (IPSEC_ENABLED(ipv4) && 264 IPSEC_CHECK_POLICY(ipv4, n, inp) != 0) { 265 m_freem(n); 266 return (0); 267 } 268 if (up->u_flags & UF_ESPINUDP) {/* IPSec UDP encaps. */ 269 if (IPSEC_ENABLED(ipv4) && 270 UDPENCAP_INPUT(ipv4, n, off, AF_INET) != 0) 271 return (0); /* Consumed. */ 272 } 273 #endif /* IPSEC */ 274 #ifdef MAC 275 if (mac_inpcb_check_deliver(inp, n) != 0) { 276 m_freem(n); 277 return (0); 278 } 279 #endif /* MAC */ 280 if (inp->inp_flags & INP_CONTROLOPTS || 281 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 282 #ifdef INET6 283 if (inp->inp_vflag & INP_IPV6) 284 (void)ip6_savecontrol_v4(inp, n, &opts, NULL); 285 else 286 #endif /* INET6 */ 287 ip_savecontrol(inp, &opts, ip, n); 288 } 289 if ((inp->inp_vflag & INP_IPV4) && (inp->inp_flags2 & INP_ORIGDSTADDR)) { 290 tmpopts = sbcreatecontrol(&udp_in[1], 291 sizeof(struct sockaddr_in), IP_ORIGDSTADDR, IPPROTO_IP, 292 M_NOWAIT); 293 if (tmpopts) { 294 if (opts) { 295 tmpopts->m_next = opts; 296 opts = tmpopts; 297 } else 298 opts = tmpopts; 299 } 300 } 301 #ifdef INET6 302 if (inp->inp_vflag & INP_IPV6) { 303 bzero(&udp_in6, sizeof(udp_in6)); 304 udp_in6.sin6_len = sizeof(udp_in6); 305 udp_in6.sin6_family = AF_INET6; 306 in6_sin_2_v4mapsin6(&udp_in[0], &udp_in6); 307 append_sa = (struct sockaddr *)&udp_in6; 308 } else 309 #endif /* INET6 */ 310 append_sa = (struct sockaddr *)&udp_in[0]; 311 m_adj(n, off); 312 313 so = inp->inp_socket; 314 SOCKBUF_LOCK(&so->so_rcv); 315 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 316 soroverflow_locked(so); 317 m_freem(n); 318 if (opts) 319 m_freem(opts); 320 UDPSTAT_INC(udps_fullsock); 321 } else 322 sorwakeup_locked(so); 323 return (0); 324 } 325 326 static bool 327 udp_multi_match(const struct inpcb *inp, void *v) 328 { 329 struct ip *ip = v; 330 struct udphdr *uh = (struct udphdr *)(ip + 1); 331 332 if (inp->inp_lport != uh->uh_dport) 333 return (false); 334 #ifdef INET6 335 if ((inp->inp_vflag & INP_IPV4) == 0) 336 return (false); 337 #endif 338 if (inp->inp_laddr.s_addr != INADDR_ANY && 339 inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 340 return (false); 341 if (inp->inp_faddr.s_addr != INADDR_ANY && 342 inp->inp_faddr.s_addr != ip->ip_src.s_addr) 343 return (false); 344 if (inp->inp_fport != 0 && 345 inp->inp_fport != uh->uh_sport) 346 return (false); 347 348 return (true); 349 } 350 351 static int 352 udp_multi_input(struct mbuf *m, int proto, struct sockaddr_in *udp_in) 353 { 354 struct ip *ip = mtod(m, struct ip *); 355 struct inpcb_iterator inpi = INP_ITERATOR(udp_get_inpcbinfo(proto), 356 INPLOOKUP_RLOCKPCB, udp_multi_match, ip); 357 #ifdef KDTRACE_HOOKS 358 struct udphdr *uh = (struct udphdr *)(ip + 1); 359 #endif 360 struct inpcb *inp; 361 struct mbuf *n; 362 int appends = 0; 363 364 MPASS(ip->ip_hl == sizeof(struct ip) >> 2); 365 366 while ((inp = inp_next(&inpi)) != NULL) { 367 /* 368 * XXXRW: Because we weren't holding either the inpcb 369 * or the hash lock when we checked for a match 370 * before, we should probably recheck now that the 371 * inpcb lock is held. 372 */ 373 /* 374 * Handle socket delivery policy for any-source 375 * and source-specific multicast. [RFC3678] 376 */ 377 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 378 struct ip_moptions *imo; 379 struct sockaddr_in group; 380 int blocked; 381 382 imo = inp->inp_moptions; 383 if (imo == NULL) 384 continue; 385 bzero(&group, sizeof(struct sockaddr_in)); 386 group.sin_len = sizeof(struct sockaddr_in); 387 group.sin_family = AF_INET; 388 group.sin_addr = ip->ip_dst; 389 390 blocked = imo_multi_filter(imo, m->m_pkthdr.rcvif, 391 (struct sockaddr *)&group, 392 (struct sockaddr *)&udp_in[0]); 393 if (blocked != MCAST_PASS) { 394 if (blocked == MCAST_NOTGMEMBER) 395 IPSTAT_INC(ips_notmember); 396 if (blocked == MCAST_NOTSMEMBER || 397 blocked == MCAST_MUTED) 398 UDPSTAT_INC(udps_filtermcast); 399 continue; 400 } 401 } 402 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) { 403 if (proto == IPPROTO_UDPLITE) 404 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh); 405 else 406 UDP_PROBE(receive, NULL, inp, ip, inp, uh); 407 if (udp_append(inp, ip, n, sizeof(struct ip), udp_in)) { 408 break; 409 } else 410 appends++; 411 } 412 /* 413 * Don't look for additional matches if this one does 414 * not have either the SO_REUSEPORT or SO_REUSEADDR 415 * socket options set. This heuristic avoids 416 * searching through all pcbs in the common case of a 417 * non-shared port. It assumes that an application 418 * will never clear these options after setting them. 419 */ 420 if ((inp->inp_socket->so_options & 421 (SO_REUSEPORT|SO_REUSEPORT_LB|SO_REUSEADDR)) == 0) { 422 INP_RUNLOCK(inp); 423 break; 424 } 425 } 426 427 if (appends == 0) { 428 /* 429 * No matching pcb found; discard datagram. (No need 430 * to send an ICMP Port Unreachable for a broadcast 431 * or multicast datgram.) 432 */ 433 UDPSTAT_INC(udps_noport); 434 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) 435 UDPSTAT_INC(udps_noportmcast); 436 else 437 UDPSTAT_INC(udps_noportbcast); 438 } 439 m_freem(m); 440 441 return (IPPROTO_DONE); 442 } 443 444 static int 445 udp_input(struct mbuf **mp, int *offp, int proto) 446 { 447 struct ip *ip; 448 struct udphdr *uh; 449 struct ifnet *ifp; 450 struct inpcb *inp; 451 uint16_t len, ip_len; 452 struct inpcbinfo *pcbinfo; 453 struct sockaddr_in udp_in[2]; 454 struct mbuf *m; 455 struct m_tag *fwd_tag; 456 int cscov_partial, iphlen; 457 458 m = *mp; 459 iphlen = *offp; 460 ifp = m->m_pkthdr.rcvif; 461 *mp = NULL; 462 UDPSTAT_INC(udps_ipackets); 463 464 /* 465 * Strip IP options, if any; should skip this, make available to 466 * user, and use on returned packets, but we don't yet have a way to 467 * check the checksum with options still present. 468 */ 469 if (iphlen > sizeof (struct ip)) { 470 ip_stripoptions(m); 471 iphlen = sizeof(struct ip); 472 } 473 474 /* 475 * Get IP and UDP header together in first mbuf. 476 */ 477 if (m->m_len < iphlen + sizeof(struct udphdr)) { 478 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == NULL) { 479 UDPSTAT_INC(udps_hdrops); 480 return (IPPROTO_DONE); 481 } 482 } 483 ip = mtod(m, struct ip *); 484 uh = (struct udphdr *)((caddr_t)ip + iphlen); 485 cscov_partial = (proto == IPPROTO_UDPLITE) ? 1 : 0; 486 487 /* 488 * Destination port of 0 is illegal, based on RFC768. 489 */ 490 if (uh->uh_dport == 0) 491 goto badunlocked; 492 493 /* 494 * Construct sockaddr format source address. Stuff source address 495 * and datagram in user buffer. 496 */ 497 bzero(&udp_in[0], sizeof(struct sockaddr_in) * 2); 498 udp_in[0].sin_len = sizeof(struct sockaddr_in); 499 udp_in[0].sin_family = AF_INET; 500 udp_in[0].sin_port = uh->uh_sport; 501 udp_in[0].sin_addr = ip->ip_src; 502 udp_in[1].sin_len = sizeof(struct sockaddr_in); 503 udp_in[1].sin_family = AF_INET; 504 udp_in[1].sin_port = uh->uh_dport; 505 udp_in[1].sin_addr = ip->ip_dst; 506 507 /* 508 * Make mbuf data length reflect UDP length. If not enough data to 509 * reflect UDP length, drop. 510 */ 511 len = ntohs((u_short)uh->uh_ulen); 512 ip_len = ntohs(ip->ip_len) - iphlen; 513 if (proto == IPPROTO_UDPLITE && (len == 0 || len == ip_len)) { 514 /* Zero means checksum over the complete packet. */ 515 if (len == 0) 516 len = ip_len; 517 cscov_partial = 0; 518 } 519 if (ip_len != len) { 520 if (len > ip_len || len < sizeof(struct udphdr)) { 521 UDPSTAT_INC(udps_badlen); 522 goto badunlocked; 523 } 524 if (proto == IPPROTO_UDP) 525 m_adj(m, len - ip_len); 526 } 527 528 /* 529 * Checksum extended UDP header and data. 530 */ 531 if (uh->uh_sum) { 532 u_short uh_sum; 533 534 if ((m->m_pkthdr.csum_flags & CSUM_DATA_VALID) && 535 !cscov_partial) { 536 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 537 uh_sum = m->m_pkthdr.csum_data; 538 else 539 uh_sum = in_pseudo(ip->ip_src.s_addr, 540 ip->ip_dst.s_addr, htonl((u_short)len + 541 m->m_pkthdr.csum_data + proto)); 542 uh_sum ^= 0xffff; 543 } else { 544 char b[offsetof(struct ipovly, ih_src)]; 545 struct ipovly *ipov = (struct ipovly *)ip; 546 547 bcopy(ipov, b, sizeof(b)); 548 bzero(ipov, sizeof(ipov->ih_x1)); 549 ipov->ih_len = (proto == IPPROTO_UDP) ? 550 uh->uh_ulen : htons(ip_len); 551 uh_sum = in_cksum(m, len + sizeof (struct ip)); 552 bcopy(b, ipov, sizeof(b)); 553 } 554 if (uh_sum) { 555 UDPSTAT_INC(udps_badsum); 556 m_freem(m); 557 return (IPPROTO_DONE); 558 } 559 } else { 560 if (proto == IPPROTO_UDP) { 561 UDPSTAT_INC(udps_nosum); 562 } else { 563 /* UDPLite requires a checksum */ 564 /* XXX: What is the right UDPLite MIB counter here? */ 565 m_freem(m); 566 return (IPPROTO_DONE); 567 } 568 } 569 570 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 571 in_broadcast(ip->ip_dst, ifp)) 572 return (udp_multi_input(m, proto, udp_in)); 573 574 pcbinfo = udp_get_inpcbinfo(proto); 575 576 /* 577 * Locate pcb for datagram. 578 * 579 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. 580 */ 581 if ((m->m_flags & M_IP_NEXTHOP) && 582 (fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL) { 583 struct sockaddr_in *next_hop; 584 585 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 586 587 /* 588 * Transparently forwarded. Pretend to be the destination. 589 * Already got one like this? 590 */ 591 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport, 592 ip->ip_dst, uh->uh_dport, INPLOOKUP_RLOCKPCB, ifp, m); 593 if (!inp) { 594 /* 595 * It's new. Try to find the ambushing socket. 596 * Because we've rewritten the destination address, 597 * any hardware-generated hash is ignored. 598 */ 599 inp = in_pcblookup(pcbinfo, ip->ip_src, 600 uh->uh_sport, next_hop->sin_addr, 601 next_hop->sin_port ? htons(next_hop->sin_port) : 602 uh->uh_dport, INPLOOKUP_WILDCARD | 603 INPLOOKUP_RLOCKPCB, ifp); 604 } 605 /* Remove the tag from the packet. We don't need it anymore. */ 606 m_tag_delete(m, fwd_tag); 607 m->m_flags &= ~M_IP_NEXTHOP; 608 } else 609 inp = in_pcblookup_mbuf(pcbinfo, ip->ip_src, uh->uh_sport, 610 ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD | 611 INPLOOKUP_RLOCKPCB, ifp, m); 612 if (inp == NULL) { 613 if (V_udp_log_in_vain) { 614 char src[INET_ADDRSTRLEN]; 615 char dst[INET_ADDRSTRLEN]; 616 617 log(LOG_INFO, 618 "Connection attempt to UDP %s:%d from %s:%d\n", 619 inet_ntoa_r(ip->ip_dst, dst), ntohs(uh->uh_dport), 620 inet_ntoa_r(ip->ip_src, src), ntohs(uh->uh_sport)); 621 } 622 if (proto == IPPROTO_UDPLITE) 623 UDPLITE_PROBE(receive, NULL, NULL, ip, NULL, uh); 624 else 625 UDP_PROBE(receive, NULL, NULL, ip, NULL, uh); 626 UDPSTAT_INC(udps_noport); 627 if (m->m_flags & (M_BCAST | M_MCAST)) { 628 UDPSTAT_INC(udps_noportbcast); 629 goto badunlocked; 630 } 631 if (V_udp_blackhole && (V_udp_blackhole_local || 632 !in_localip(ip->ip_src))) 633 goto badunlocked; 634 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 635 goto badunlocked; 636 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 637 return (IPPROTO_DONE); 638 } 639 640 /* 641 * Check the minimum TTL for socket. 642 */ 643 INP_RLOCK_ASSERT(inp); 644 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) { 645 if (proto == IPPROTO_UDPLITE) 646 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh); 647 else 648 UDP_PROBE(receive, NULL, inp, ip, inp, uh); 649 INP_RUNLOCK(inp); 650 m_freem(m); 651 return (IPPROTO_DONE); 652 } 653 if (cscov_partial) { 654 struct udpcb *up; 655 656 up = intoudpcb(inp); 657 if (up->u_rxcslen == 0 || up->u_rxcslen > len) { 658 INP_RUNLOCK(inp); 659 m_freem(m); 660 return (IPPROTO_DONE); 661 } 662 } 663 664 if (proto == IPPROTO_UDPLITE) 665 UDPLITE_PROBE(receive, NULL, inp, ip, inp, uh); 666 else 667 UDP_PROBE(receive, NULL, inp, ip, inp, uh); 668 if (udp_append(inp, ip, m, iphlen, udp_in) == 0) 669 INP_RUNLOCK(inp); 670 return (IPPROTO_DONE); 671 672 badunlocked: 673 m_freem(m); 674 return (IPPROTO_DONE); 675 } 676 #endif /* INET */ 677 678 /* 679 * Notify a udp user of an asynchronous error; just wake up so that they can 680 * collect error status. 681 */ 682 struct inpcb * 683 udp_notify(struct inpcb *inp, int errno) 684 { 685 686 INP_WLOCK_ASSERT(inp); 687 if ((errno == EHOSTUNREACH || errno == ENETUNREACH || 688 errno == EHOSTDOWN) && inp->inp_route.ro_nh) { 689 NH_FREE(inp->inp_route.ro_nh); 690 inp->inp_route.ro_nh = (struct nhop_object *)NULL; 691 } 692 693 inp->inp_socket->so_error = errno; 694 sorwakeup(inp->inp_socket); 695 sowwakeup(inp->inp_socket); 696 return (inp); 697 } 698 699 #ifdef INET 700 static void 701 udp_common_ctlinput(struct icmp *icmp, struct inpcbinfo *pcbinfo) 702 { 703 struct ip *ip = &icmp->icmp_ip; 704 struct udphdr *uh; 705 struct inpcb *inp; 706 707 if (icmp_errmap(icmp) == 0) 708 return; 709 710 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 711 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport, ip->ip_src, 712 uh->uh_sport, INPLOOKUP_WLOCKPCB, NULL); 713 if (inp != NULL) { 714 INP_WLOCK_ASSERT(inp); 715 if (inp->inp_socket != NULL) 716 udp_notify(inp, icmp_errmap(icmp)); 717 INP_WUNLOCK(inp); 718 } else { 719 inp = in_pcblookup(pcbinfo, ip->ip_dst, uh->uh_dport, 720 ip->ip_src, uh->uh_sport, 721 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL); 722 if (inp != NULL) { 723 struct udpcb *up; 724 udp_tun_icmp_t *func; 725 726 up = intoudpcb(inp); 727 func = up->u_icmp_func; 728 INP_RUNLOCK(inp); 729 if (func != NULL) 730 func(icmp); 731 } 732 } 733 } 734 735 static void 736 udp_ctlinput(struct icmp *icmp) 737 { 738 739 return (udp_common_ctlinput(icmp, &V_udbinfo)); 740 } 741 742 static void 743 udplite_ctlinput(struct icmp *icmp) 744 { 745 746 return (udp_common_ctlinput(icmp, &V_ulitecbinfo)); 747 } 748 #endif /* INET */ 749 750 static int 751 udp_pcblist(SYSCTL_HANDLER_ARGS) 752 { 753 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_udbinfo, 754 INPLOOKUP_RLOCKPCB); 755 struct xinpgen xig; 756 struct inpcb *inp; 757 int error; 758 759 if (req->newptr != 0) 760 return (EPERM); 761 762 if (req->oldptr == 0) { 763 int n; 764 765 n = V_udbinfo.ipi_count; 766 n += imax(n / 8, 10); 767 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb); 768 return (0); 769 } 770 771 if ((error = sysctl_wire_old_buffer(req, 0)) != 0) 772 return (error); 773 774 bzero(&xig, sizeof(xig)); 775 xig.xig_len = sizeof xig; 776 xig.xig_count = V_udbinfo.ipi_count; 777 xig.xig_gen = V_udbinfo.ipi_gencnt; 778 xig.xig_sogen = so_gencnt; 779 error = SYSCTL_OUT(req, &xig, sizeof xig); 780 if (error) 781 return (error); 782 783 while ((inp = inp_next(&inpi)) != NULL) { 784 if (inp->inp_gencnt <= xig.xig_gen && 785 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 786 struct xinpcb xi; 787 788 in_pcbtoxinpcb(inp, &xi); 789 error = SYSCTL_OUT(req, &xi, sizeof xi); 790 if (error) { 791 INP_RUNLOCK(inp); 792 break; 793 } 794 } 795 } 796 797 if (!error) { 798 /* 799 * Give the user an updated idea of our state. If the 800 * generation differs from what we told her before, she knows 801 * that something happened while we were processing this 802 * request, and it might be necessary to retry. 803 */ 804 xig.xig_gen = V_udbinfo.ipi_gencnt; 805 xig.xig_sogen = so_gencnt; 806 xig.xig_count = V_udbinfo.ipi_count; 807 error = SYSCTL_OUT(req, &xig, sizeof xig); 808 } 809 810 return (error); 811 } 812 813 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, 814 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 815 udp_pcblist, "S,xinpcb", 816 "List of active UDP sockets"); 817 818 #ifdef INET 819 static int 820 udp_getcred(SYSCTL_HANDLER_ARGS) 821 { 822 struct xucred xuc; 823 struct sockaddr_in addrs[2]; 824 struct epoch_tracker et; 825 struct inpcb *inp; 826 int error; 827 828 error = priv_check(req->td, PRIV_NETINET_GETCRED); 829 if (error) 830 return (error); 831 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 832 if (error) 833 return (error); 834 NET_EPOCH_ENTER(et); 835 inp = in_pcblookup(&V_udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 836 addrs[0].sin_addr, addrs[0].sin_port, 837 INPLOOKUP_WILDCARD | INPLOOKUP_RLOCKPCB, NULL); 838 NET_EPOCH_EXIT(et); 839 if (inp != NULL) { 840 INP_RLOCK_ASSERT(inp); 841 if (inp->inp_socket == NULL) 842 error = ENOENT; 843 if (error == 0) 844 error = cr_canseeinpcb(req->td->td_ucred, inp); 845 if (error == 0) 846 cru2x(inp->inp_cred, &xuc); 847 INP_RUNLOCK(inp); 848 } else 849 error = ENOENT; 850 if (error == 0) 851 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 852 return (error); 853 } 854 855 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 856 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE, 857 0, 0, udp_getcred, "S,xucred", 858 "Get the xucred of a UDP connection"); 859 #endif /* INET */ 860 861 int 862 udp_ctloutput(struct socket *so, struct sockopt *sopt) 863 { 864 struct inpcb *inp; 865 struct udpcb *up; 866 int isudplite, error, optval; 867 868 error = 0; 869 isudplite = (so->so_proto->pr_protocol == IPPROTO_UDPLITE) ? 1 : 0; 870 inp = sotoinpcb(so); 871 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 872 INP_WLOCK(inp); 873 if (sopt->sopt_level != so->so_proto->pr_protocol) { 874 #ifdef INET6 875 if (INP_CHECK_SOCKAF(so, AF_INET6)) { 876 INP_WUNLOCK(inp); 877 error = ip6_ctloutput(so, sopt); 878 } 879 #endif 880 #if defined(INET) && defined(INET6) 881 else 882 #endif 883 #ifdef INET 884 { 885 INP_WUNLOCK(inp); 886 error = ip_ctloutput(so, sopt); 887 } 888 #endif 889 return (error); 890 } 891 892 switch (sopt->sopt_dir) { 893 case SOPT_SET: 894 switch (sopt->sopt_name) { 895 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 896 #if defined(INET) || defined(INET6) 897 case UDP_ENCAP: 898 #ifdef INET 899 if (INP_SOCKAF(so) == AF_INET) { 900 if (!IPSEC_ENABLED(ipv4)) { 901 INP_WUNLOCK(inp); 902 return (ENOPROTOOPT); 903 } 904 error = UDPENCAP_PCBCTL(ipv4, inp, sopt); 905 break; 906 } 907 #endif /* INET */ 908 #ifdef INET6 909 if (INP_SOCKAF(so) == AF_INET6) { 910 if (!IPSEC_ENABLED(ipv6)) { 911 INP_WUNLOCK(inp); 912 return (ENOPROTOOPT); 913 } 914 error = UDPENCAP_PCBCTL(ipv6, inp, sopt); 915 break; 916 } 917 #endif /* INET6 */ 918 INP_WUNLOCK(inp); 919 return (EINVAL); 920 #endif /* INET || INET6 */ 921 922 #endif /* IPSEC */ 923 case UDPLITE_SEND_CSCOV: 924 case UDPLITE_RECV_CSCOV: 925 if (!isudplite) { 926 INP_WUNLOCK(inp); 927 error = ENOPROTOOPT; 928 break; 929 } 930 INP_WUNLOCK(inp); 931 error = sooptcopyin(sopt, &optval, sizeof(optval), 932 sizeof(optval)); 933 if (error != 0) 934 break; 935 inp = sotoinpcb(so); 936 KASSERT(inp != NULL, ("%s: inp == NULL", __func__)); 937 INP_WLOCK(inp); 938 up = intoudpcb(inp); 939 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 940 if ((optval != 0 && optval < 8) || (optval > 65535)) { 941 INP_WUNLOCK(inp); 942 error = EINVAL; 943 break; 944 } 945 if (sopt->sopt_name == UDPLITE_SEND_CSCOV) 946 up->u_txcslen = optval; 947 else 948 up->u_rxcslen = optval; 949 INP_WUNLOCK(inp); 950 break; 951 default: 952 INP_WUNLOCK(inp); 953 error = ENOPROTOOPT; 954 break; 955 } 956 break; 957 case SOPT_GET: 958 switch (sopt->sopt_name) { 959 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 960 #if defined(INET) || defined(INET6) 961 case UDP_ENCAP: 962 #ifdef INET 963 if (INP_SOCKAF(so) == AF_INET) { 964 if (!IPSEC_ENABLED(ipv4)) { 965 INP_WUNLOCK(inp); 966 return (ENOPROTOOPT); 967 } 968 error = UDPENCAP_PCBCTL(ipv4, inp, sopt); 969 break; 970 } 971 #endif /* INET */ 972 #ifdef INET6 973 if (INP_SOCKAF(so) == AF_INET6) { 974 if (!IPSEC_ENABLED(ipv6)) { 975 INP_WUNLOCK(inp); 976 return (ENOPROTOOPT); 977 } 978 error = UDPENCAP_PCBCTL(ipv6, inp, sopt); 979 break; 980 } 981 #endif /* INET6 */ 982 INP_WUNLOCK(inp); 983 return (EINVAL); 984 #endif /* INET || INET6 */ 985 986 #endif /* IPSEC */ 987 case UDPLITE_SEND_CSCOV: 988 case UDPLITE_RECV_CSCOV: 989 if (!isudplite) { 990 INP_WUNLOCK(inp); 991 error = ENOPROTOOPT; 992 break; 993 } 994 up = intoudpcb(inp); 995 KASSERT(up != NULL, ("%s: up == NULL", __func__)); 996 if (sopt->sopt_name == UDPLITE_SEND_CSCOV) 997 optval = up->u_txcslen; 998 else 999 optval = up->u_rxcslen; 1000 INP_WUNLOCK(inp); 1001 error = sooptcopyout(sopt, &optval, sizeof(optval)); 1002 break; 1003 default: 1004 INP_WUNLOCK(inp); 1005 error = ENOPROTOOPT; 1006 break; 1007 } 1008 break; 1009 } 1010 return (error); 1011 } 1012 1013 #ifdef INET 1014 #ifdef INET6 1015 /* The logic here is derived from ip6_setpktopt(). See comments there. */ 1016 static int 1017 udp_v4mapped_pktinfo(struct cmsghdr *cm, struct sockaddr_in * src, 1018 struct inpcb *inp, int flags) 1019 { 1020 struct ifnet *ifp; 1021 struct in6_pktinfo *pktinfo; 1022 struct in_addr ia; 1023 1024 if ((flags & PRUS_IPV6) == 0) 1025 return (0); 1026 1027 if (cm->cmsg_level != IPPROTO_IPV6) 1028 return (0); 1029 1030 if (cm->cmsg_type != IPV6_2292PKTINFO && 1031 cm->cmsg_type != IPV6_PKTINFO) 1032 return (0); 1033 1034 if (cm->cmsg_len != 1035 CMSG_LEN(sizeof(struct in6_pktinfo))) 1036 return (EINVAL); 1037 1038 pktinfo = (struct in6_pktinfo *)CMSG_DATA(cm); 1039 if (!IN6_IS_ADDR_V4MAPPED(&pktinfo->ipi6_addr) && 1040 !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) 1041 return (EINVAL); 1042 1043 /* Validate the interface index if specified. */ 1044 if (pktinfo->ipi6_ifindex) { 1045 struct epoch_tracker et; 1046 1047 NET_EPOCH_ENTER(et); 1048 ifp = ifnet_byindex(pktinfo->ipi6_ifindex); 1049 NET_EPOCH_EXIT(et); /* XXXGL: unsafe ifp */ 1050 if (ifp == NULL) 1051 return (ENXIO); 1052 } else 1053 ifp = NULL; 1054 if (ifp != NULL && !IN6_IS_ADDR_UNSPECIFIED(&pktinfo->ipi6_addr)) { 1055 ia.s_addr = pktinfo->ipi6_addr.s6_addr32[3]; 1056 if (in_ifhasaddr(ifp, ia) == 0) 1057 return (EADDRNOTAVAIL); 1058 } 1059 1060 bzero(src, sizeof(*src)); 1061 src->sin_family = AF_INET; 1062 src->sin_len = sizeof(*src); 1063 src->sin_port = inp->inp_lport; 1064 src->sin_addr.s_addr = pktinfo->ipi6_addr.s6_addr32[3]; 1065 1066 return (0); 1067 } 1068 #endif /* INET6 */ 1069 1070 int 1071 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1072 struct mbuf *control, struct thread *td) 1073 { 1074 struct inpcb *inp; 1075 struct udpiphdr *ui; 1076 int len, error = 0; 1077 struct in_addr faddr, laddr; 1078 struct cmsghdr *cm; 1079 struct inpcbinfo *pcbinfo; 1080 struct sockaddr_in *sin, src; 1081 struct epoch_tracker et; 1082 int cscov_partial = 0; 1083 int ipflags = 0; 1084 u_short fport, lport; 1085 u_char tos, vflagsav; 1086 uint8_t pr; 1087 uint16_t cscov = 0; 1088 uint32_t flowid = 0; 1089 uint8_t flowtype = M_HASHTYPE_NONE; 1090 bool use_cached_route; 1091 1092 inp = sotoinpcb(so); 1093 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1094 1095 if (addr != NULL) { 1096 if (addr->sa_family != AF_INET) 1097 error = EAFNOSUPPORT; 1098 else if (addr->sa_len != sizeof(struct sockaddr_in)) 1099 error = EINVAL; 1100 if (__predict_false(error != 0)) { 1101 m_freem(control); 1102 m_freem(m); 1103 return (error); 1104 } 1105 } 1106 1107 len = m->m_pkthdr.len; 1108 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 1109 if (control) 1110 m_freem(control); 1111 m_freem(m); 1112 return (EMSGSIZE); 1113 } 1114 1115 src.sin_family = 0; 1116 sin = (struct sockaddr_in *)addr; 1117 1118 /* 1119 * udp_send() may need to temporarily bind or connect the current 1120 * inpcb. As such, we don't know up front whether we will need the 1121 * pcbinfo lock or not. Do any work to decide what is needed up 1122 * front before acquiring any locks. 1123 * 1124 * We will need network epoch in either case, to safely lookup into 1125 * pcb hash. 1126 */ 1127 use_cached_route = sin == NULL || (inp->inp_laddr.s_addr == INADDR_ANY && inp->inp_lport == 0); 1128 if (use_cached_route || (flags & PRUS_IPV6) != 0) 1129 INP_WLOCK(inp); 1130 else 1131 INP_RLOCK(inp); 1132 NET_EPOCH_ENTER(et); 1133 tos = inp->inp_ip_tos; 1134 if (control != NULL) { 1135 /* 1136 * XXX: Currently, we assume all the optional information is 1137 * stored in a single mbuf. 1138 */ 1139 if (control->m_next) { 1140 m_freem(control); 1141 error = EINVAL; 1142 goto release; 1143 } 1144 for (; control->m_len > 0; 1145 control->m_data += CMSG_ALIGN(cm->cmsg_len), 1146 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 1147 cm = mtod(control, struct cmsghdr *); 1148 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 1149 || cm->cmsg_len > control->m_len) { 1150 error = EINVAL; 1151 break; 1152 } 1153 #ifdef INET6 1154 error = udp_v4mapped_pktinfo(cm, &src, inp, flags); 1155 if (error != 0) 1156 break; 1157 #endif 1158 if (cm->cmsg_level != IPPROTO_IP) 1159 continue; 1160 1161 switch (cm->cmsg_type) { 1162 case IP_SENDSRCADDR: 1163 if (cm->cmsg_len != 1164 CMSG_LEN(sizeof(struct in_addr))) { 1165 error = EINVAL; 1166 break; 1167 } 1168 bzero(&src, sizeof(src)); 1169 src.sin_family = AF_INET; 1170 src.sin_len = sizeof(src); 1171 src.sin_port = inp->inp_lport; 1172 src.sin_addr = 1173 *(struct in_addr *)CMSG_DATA(cm); 1174 break; 1175 1176 case IP_TOS: 1177 if (cm->cmsg_len != CMSG_LEN(sizeof(u_char))) { 1178 error = EINVAL; 1179 break; 1180 } 1181 tos = *(u_char *)CMSG_DATA(cm); 1182 break; 1183 1184 case IP_FLOWID: 1185 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) { 1186 error = EINVAL; 1187 break; 1188 } 1189 flowid = *(uint32_t *) CMSG_DATA(cm); 1190 break; 1191 1192 case IP_FLOWTYPE: 1193 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) { 1194 error = EINVAL; 1195 break; 1196 } 1197 flowtype = *(uint32_t *) CMSG_DATA(cm); 1198 break; 1199 1200 #ifdef RSS 1201 case IP_RSSBUCKETID: 1202 if (cm->cmsg_len != CMSG_LEN(sizeof(uint32_t))) { 1203 error = EINVAL; 1204 break; 1205 } 1206 /* This is just a placeholder for now */ 1207 break; 1208 #endif /* RSS */ 1209 default: 1210 error = ENOPROTOOPT; 1211 break; 1212 } 1213 if (error) 1214 break; 1215 } 1216 m_freem(control); 1217 control = NULL; 1218 } 1219 if (error) 1220 goto release; 1221 1222 pr = inp->inp_socket->so_proto->pr_protocol; 1223 pcbinfo = udp_get_inpcbinfo(pr); 1224 1225 /* 1226 * If the IP_SENDSRCADDR control message was specified, override the 1227 * source address for this datagram. Its use is invalidated if the 1228 * address thus specified is incomplete or clobbers other inpcbs. 1229 */ 1230 laddr = inp->inp_laddr; 1231 lport = inp->inp_lport; 1232 if (src.sin_family == AF_INET) { 1233 if ((lport == 0) || 1234 (laddr.s_addr == INADDR_ANY && 1235 src.sin_addr.s_addr == INADDR_ANY)) { 1236 error = EINVAL; 1237 goto release; 1238 } 1239 if ((flags & PRUS_IPV6) != 0) { 1240 vflagsav = inp->inp_vflag; 1241 inp->inp_vflag |= INP_IPV4; 1242 inp->inp_vflag &= ~INP_IPV6; 1243 } 1244 INP_HASH_WLOCK(pcbinfo); 1245 error = in_pcbbind_setup(inp, &src, &laddr.s_addr, &lport, 1246 td->td_ucred); 1247 INP_HASH_WUNLOCK(pcbinfo); 1248 if ((flags & PRUS_IPV6) != 0) 1249 inp->inp_vflag = vflagsav; 1250 if (error) 1251 goto release; 1252 } 1253 1254 /* 1255 * If a UDP socket has been connected, then a local address/port will 1256 * have been selected and bound. 1257 * 1258 * If a UDP socket has not been connected to, then an explicit 1259 * destination address must be used, in which case a local 1260 * address/port may not have been selected and bound. 1261 */ 1262 if (sin != NULL) { 1263 INP_LOCK_ASSERT(inp); 1264 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1265 error = EISCONN; 1266 goto release; 1267 } 1268 1269 /* 1270 * Jail may rewrite the destination address, so let it do 1271 * that before we use it. 1272 */ 1273 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1274 if (error) 1275 goto release; 1276 1277 /* 1278 * If a local address or port hasn't yet been selected, or if 1279 * the destination address needs to be rewritten due to using 1280 * a special INADDR_ constant, invoke in_pcbconnect_setup() 1281 * to do the heavy lifting. Once a port is selected, we 1282 * commit the binding back to the socket; we also commit the 1283 * binding of the address if in jail. 1284 * 1285 * If we already have a valid binding and we're not 1286 * requesting a destination address rewrite, use a fast path. 1287 */ 1288 if (inp->inp_laddr.s_addr == INADDR_ANY || 1289 inp->inp_lport == 0 || 1290 sin->sin_addr.s_addr == INADDR_ANY || 1291 sin->sin_addr.s_addr == INADDR_BROADCAST) { 1292 if ((flags & PRUS_IPV6) != 0) { 1293 vflagsav = inp->inp_vflag; 1294 inp->inp_vflag |= INP_IPV4; 1295 inp->inp_vflag &= ~INP_IPV6; 1296 } 1297 INP_HASH_WLOCK(pcbinfo); 1298 error = in_pcbconnect_setup(inp, sin, &laddr.s_addr, 1299 &lport, &faddr.s_addr, &fport, td->td_ucred); 1300 if ((flags & PRUS_IPV6) != 0) 1301 inp->inp_vflag = vflagsav; 1302 if (error) { 1303 INP_HASH_WUNLOCK(pcbinfo); 1304 goto release; 1305 } 1306 1307 /* 1308 * XXXRW: Why not commit the port if the address is 1309 * !INADDR_ANY? 1310 */ 1311 /* Commit the local port if newly assigned. */ 1312 if (inp->inp_laddr.s_addr == INADDR_ANY && 1313 inp->inp_lport == 0) { 1314 INP_WLOCK_ASSERT(inp); 1315 /* 1316 * Remember addr if jailed, to prevent 1317 * rebinding. 1318 */ 1319 if (prison_flag(td->td_ucred, PR_IP4)) 1320 inp->inp_laddr = laddr; 1321 inp->inp_lport = lport; 1322 error = in_pcbinshash(inp); 1323 INP_HASH_WUNLOCK(pcbinfo); 1324 if (error != 0) { 1325 inp->inp_lport = 0; 1326 error = EAGAIN; 1327 goto release; 1328 } 1329 inp->inp_flags |= INP_ANONPORT; 1330 } else 1331 INP_HASH_WUNLOCK(pcbinfo); 1332 } else { 1333 faddr = sin->sin_addr; 1334 fport = sin->sin_port; 1335 } 1336 } else { 1337 INP_LOCK_ASSERT(inp); 1338 faddr = inp->inp_faddr; 1339 fport = inp->inp_fport; 1340 if (faddr.s_addr == INADDR_ANY) { 1341 error = ENOTCONN; 1342 goto release; 1343 } 1344 } 1345 1346 /* 1347 * Calculate data length and get a mbuf for UDP, IP, and possible 1348 * link-layer headers. Immediate slide the data pointer back forward 1349 * since we won't use that space at this layer. 1350 */ 1351 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_NOWAIT); 1352 if (m == NULL) { 1353 error = ENOBUFS; 1354 goto release; 1355 } 1356 m->m_data += max_linkhdr; 1357 m->m_len -= max_linkhdr; 1358 m->m_pkthdr.len -= max_linkhdr; 1359 1360 /* 1361 * Fill in mbuf with extended UDP header and addresses and length put 1362 * into network format. 1363 */ 1364 ui = mtod(m, struct udpiphdr *); 1365 /* 1366 * Filling only those fields of udpiphdr that participate in the 1367 * checksum calculation. The rest must be zeroed and will be filled 1368 * later. 1369 */ 1370 bzero(ui->ui_x1, sizeof(ui->ui_x1)); 1371 ui->ui_pr = pr; 1372 ui->ui_src = laddr; 1373 ui->ui_dst = faddr; 1374 ui->ui_sport = lport; 1375 ui->ui_dport = fport; 1376 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 1377 if (pr == IPPROTO_UDPLITE) { 1378 struct udpcb *up; 1379 uint16_t plen; 1380 1381 up = intoudpcb(inp); 1382 cscov = up->u_txcslen; 1383 plen = (u_short)len + sizeof(struct udphdr); 1384 if (cscov >= plen) 1385 cscov = 0; 1386 ui->ui_len = htons(plen); 1387 ui->ui_ulen = htons(cscov); 1388 /* 1389 * For UDP-Lite, checksum coverage length of zero means 1390 * the entire UDPLite packet is covered by the checksum. 1391 */ 1392 cscov_partial = (cscov == 0) ? 0 : 1; 1393 } 1394 1395 if (inp->inp_socket->so_options & SO_DONTROUTE) 1396 ipflags |= IP_ROUTETOIF; 1397 if (inp->inp_socket->so_options & SO_BROADCAST) 1398 ipflags |= IP_ALLOWBROADCAST; 1399 if (inp->inp_flags & INP_ONESBCAST) 1400 ipflags |= IP_SENDONES; 1401 1402 #ifdef MAC 1403 mac_inpcb_create_mbuf(inp, m); 1404 #endif 1405 1406 /* 1407 * Set up checksum and output datagram. 1408 */ 1409 ui->ui_sum = 0; 1410 if (pr == IPPROTO_UDPLITE) { 1411 if (inp->inp_flags & INP_ONESBCAST) 1412 faddr.s_addr = INADDR_BROADCAST; 1413 if (cscov_partial) { 1414 if ((ui->ui_sum = in_cksum(m, sizeof(struct ip) + cscov)) == 0) 1415 ui->ui_sum = 0xffff; 1416 } else { 1417 if ((ui->ui_sum = in_cksum(m, sizeof(struct udpiphdr) + len)) == 0) 1418 ui->ui_sum = 0xffff; 1419 } 1420 } else if (V_udp_cksum) { 1421 if (inp->inp_flags & INP_ONESBCAST) 1422 faddr.s_addr = INADDR_BROADCAST; 1423 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 1424 htons((u_short)len + sizeof(struct udphdr) + pr)); 1425 m->m_pkthdr.csum_flags = CSUM_UDP; 1426 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 1427 } 1428 /* 1429 * After finishing the checksum computation, fill the remaining fields 1430 * of udpiphdr. 1431 */ 1432 ((struct ip *)ui)->ip_v = IPVERSION; 1433 ((struct ip *)ui)->ip_tos = tos; 1434 ((struct ip *)ui)->ip_len = htons(sizeof(struct udpiphdr) + len); 1435 if (inp->inp_flags & INP_DONTFRAG) 1436 ((struct ip *)ui)->ip_off |= htons(IP_DF); 1437 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; 1438 UDPSTAT_INC(udps_opackets); 1439 1440 /* 1441 * Setup flowid / RSS information for outbound socket. 1442 * 1443 * Once the UDP code decides to set a flowid some other way, 1444 * this allows the flowid to be overridden by userland. 1445 */ 1446 if (flowtype != M_HASHTYPE_NONE) { 1447 m->m_pkthdr.flowid = flowid; 1448 M_HASHTYPE_SET(m, flowtype); 1449 } 1450 #if defined(ROUTE_MPATH) || defined(RSS) 1451 else if (CALC_FLOWID_OUTBOUND_SENDTO) { 1452 uint32_t hash_val, hash_type; 1453 1454 hash_val = fib4_calc_packet_hash(laddr, faddr, 1455 lport, fport, pr, &hash_type); 1456 m->m_pkthdr.flowid = hash_val; 1457 M_HASHTYPE_SET(m, hash_type); 1458 } 1459 1460 /* 1461 * Don't override with the inp cached flowid value. 1462 * 1463 * Depending upon the kind of send being done, the inp 1464 * flowid/flowtype values may actually not be appropriate 1465 * for this particular socket send. 1466 * 1467 * We should either leave the flowid at zero (which is what is 1468 * currently done) or set it to some software generated 1469 * hash value based on the packet contents. 1470 */ 1471 ipflags |= IP_NODEFAULTFLOWID; 1472 #endif /* RSS */ 1473 1474 if (pr == IPPROTO_UDPLITE) 1475 UDPLITE_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u); 1476 else 1477 UDP_PROBE(send, NULL, inp, &ui->ui_i, inp, &ui->ui_u); 1478 error = ip_output(m, inp->inp_options, 1479 use_cached_route ? &inp->inp_route : NULL, ipflags, 1480 inp->inp_moptions, inp); 1481 INP_UNLOCK(inp); 1482 NET_EPOCH_EXIT(et); 1483 return (error); 1484 1485 release: 1486 INP_UNLOCK(inp); 1487 NET_EPOCH_EXIT(et); 1488 m_freem(m); 1489 return (error); 1490 } 1491 1492 void 1493 udp_abort(struct socket *so) 1494 { 1495 struct inpcb *inp; 1496 struct inpcbinfo *pcbinfo; 1497 1498 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1499 inp = sotoinpcb(so); 1500 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 1501 INP_WLOCK(inp); 1502 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1503 INP_HASH_WLOCK(pcbinfo); 1504 in_pcbdisconnect(inp); 1505 INP_HASH_WUNLOCK(pcbinfo); 1506 soisdisconnected(so); 1507 } 1508 INP_WUNLOCK(inp); 1509 } 1510 1511 static int 1512 udp_attach(struct socket *so, int proto, struct thread *td) 1513 { 1514 static uint32_t udp_flowid; 1515 struct inpcbinfo *pcbinfo; 1516 struct inpcb *inp; 1517 struct udpcb *up; 1518 int error; 1519 1520 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1521 inp = sotoinpcb(so); 1522 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 1523 error = soreserve(so, udp_sendspace, udp_recvspace); 1524 if (error) 1525 return (error); 1526 error = in_pcballoc(so, pcbinfo); 1527 if (error) 1528 return (error); 1529 1530 inp = sotoinpcb(so); 1531 inp->inp_ip_ttl = V_ip_defttl; 1532 inp->inp_flowid = atomic_fetchadd_int(&udp_flowid, 1); 1533 inp->inp_flowtype = M_HASHTYPE_OPAQUE; 1534 up = intoudpcb(inp); 1535 bzero(&up->u_start_zero, u_zero_size); 1536 INP_WUNLOCK(inp); 1537 1538 return (0); 1539 } 1540 #endif /* INET */ 1541 1542 int 1543 udp_set_kernel_tunneling(struct socket *so, udp_tun_func_t f, udp_tun_icmp_t i, void *ctx) 1544 { 1545 struct inpcb *inp; 1546 struct udpcb *up; 1547 1548 KASSERT(so->so_type == SOCK_DGRAM, 1549 ("udp_set_kernel_tunneling: !dgram")); 1550 inp = sotoinpcb(so); 1551 KASSERT(inp != NULL, ("udp_set_kernel_tunneling: inp == NULL")); 1552 INP_WLOCK(inp); 1553 up = intoudpcb(inp); 1554 if ((f != NULL || i != NULL) && ((up->u_tun_func != NULL) || 1555 (up->u_icmp_func != NULL))) { 1556 INP_WUNLOCK(inp); 1557 return (EBUSY); 1558 } 1559 up->u_tun_func = f; 1560 up->u_icmp_func = i; 1561 up->u_tun_ctx = ctx; 1562 INP_WUNLOCK(inp); 1563 return (0); 1564 } 1565 1566 #ifdef INET 1567 static int 1568 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1569 { 1570 struct inpcb *inp; 1571 struct inpcbinfo *pcbinfo; 1572 struct sockaddr_in *sinp; 1573 int error; 1574 1575 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1576 inp = sotoinpcb(so); 1577 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1578 1579 sinp = (struct sockaddr_in *)nam; 1580 if (nam->sa_family != AF_INET) { 1581 /* 1582 * Preserve compatibility with old programs. 1583 */ 1584 if (nam->sa_family != AF_UNSPEC || 1585 nam->sa_len < offsetof(struct sockaddr_in, sin_zero) || 1586 sinp->sin_addr.s_addr != INADDR_ANY) 1587 return (EAFNOSUPPORT); 1588 nam->sa_family = AF_INET; 1589 } 1590 if (nam->sa_len != sizeof(struct sockaddr_in)) 1591 return (EINVAL); 1592 1593 INP_WLOCK(inp); 1594 INP_HASH_WLOCK(pcbinfo); 1595 error = in_pcbbind(inp, sinp, td->td_ucred); 1596 INP_HASH_WUNLOCK(pcbinfo); 1597 INP_WUNLOCK(inp); 1598 return (error); 1599 } 1600 1601 static void 1602 udp_close(struct socket *so) 1603 { 1604 struct inpcb *inp; 1605 struct inpcbinfo *pcbinfo; 1606 1607 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1608 inp = sotoinpcb(so); 1609 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1610 INP_WLOCK(inp); 1611 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1612 INP_HASH_WLOCK(pcbinfo); 1613 in_pcbdisconnect(inp); 1614 INP_HASH_WUNLOCK(pcbinfo); 1615 soisdisconnected(so); 1616 } 1617 INP_WUNLOCK(inp); 1618 } 1619 1620 static int 1621 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1622 { 1623 struct epoch_tracker et; 1624 struct inpcb *inp; 1625 struct inpcbinfo *pcbinfo; 1626 struct sockaddr_in *sin; 1627 int error; 1628 1629 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1630 inp = sotoinpcb(so); 1631 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1632 1633 sin = (struct sockaddr_in *)nam; 1634 if (sin->sin_family != AF_INET) 1635 return (EAFNOSUPPORT); 1636 if (sin->sin_len != sizeof(*sin)) 1637 return (EINVAL); 1638 1639 INP_WLOCK(inp); 1640 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1641 INP_WUNLOCK(inp); 1642 return (EISCONN); 1643 } 1644 error = prison_remote_ip4(td->td_ucred, &sin->sin_addr); 1645 if (error != 0) { 1646 INP_WUNLOCK(inp); 1647 return (error); 1648 } 1649 NET_EPOCH_ENTER(et); 1650 INP_HASH_WLOCK(pcbinfo); 1651 error = in_pcbconnect(inp, sin, td->td_ucred, true); 1652 INP_HASH_WUNLOCK(pcbinfo); 1653 NET_EPOCH_EXIT(et); 1654 if (error == 0) 1655 soisconnected(so); 1656 INP_WUNLOCK(inp); 1657 return (error); 1658 } 1659 1660 static void 1661 udp_detach(struct socket *so) 1662 { 1663 struct inpcb *inp; 1664 1665 inp = sotoinpcb(so); 1666 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1667 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY, 1668 ("udp_detach: not disconnected")); 1669 INP_WLOCK(inp); 1670 in_pcbfree(inp); 1671 } 1672 1673 int 1674 udp_disconnect(struct socket *so) 1675 { 1676 struct inpcb *inp; 1677 struct inpcbinfo *pcbinfo; 1678 1679 pcbinfo = udp_get_inpcbinfo(so->so_proto->pr_protocol); 1680 inp = sotoinpcb(so); 1681 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1682 INP_WLOCK(inp); 1683 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1684 INP_WUNLOCK(inp); 1685 return (ENOTCONN); 1686 } 1687 INP_HASH_WLOCK(pcbinfo); 1688 in_pcbdisconnect(inp); 1689 INP_HASH_WUNLOCK(pcbinfo); 1690 SOCK_LOCK(so); 1691 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1692 SOCK_UNLOCK(so); 1693 INP_WUNLOCK(inp); 1694 return (0); 1695 } 1696 #endif /* INET */ 1697 1698 int 1699 udp_shutdown(struct socket *so, enum shutdown_how how) 1700 { 1701 int error; 1702 1703 SOCK_LOCK(so); 1704 if (!(so->so_state & SS_ISCONNECTED)) 1705 /* 1706 * POSIX mandates us to just return ENOTCONN when shutdown(2) is 1707 * invoked on a datagram sockets, however historically we would 1708 * actually tear socket down. This is known to be leveraged by 1709 * some applications to unblock process waiting in recv(2) by 1710 * other process that it shares that socket with. Try to meet 1711 * both backward-compatibility and POSIX requirements by forcing 1712 * ENOTCONN but still flushing buffers and performing wakeup(9). 1713 * 1714 * XXXGL: it remains unknown what applications expect this 1715 * behavior and is this isolated to unix/dgram or inet/dgram or 1716 * both. See: D10351, D3039. 1717 */ 1718 error = ENOTCONN; 1719 else 1720 error = 0; 1721 SOCK_UNLOCK(so); 1722 1723 switch (how) { 1724 case SHUT_RD: 1725 socantrcvmore(so); 1726 sbrelease(so, SO_RCV); 1727 break; 1728 case SHUT_RDWR: 1729 socantrcvmore(so); 1730 sbrelease(so, SO_RCV); 1731 /* FALLTHROUGH */ 1732 case SHUT_WR: 1733 socantsendmore(so); 1734 } 1735 1736 return (error); 1737 } 1738 1739 #ifdef INET 1740 #define UDP_PROTOSW \ 1741 .pr_type = SOCK_DGRAM, \ 1742 .pr_flags = PR_ATOMIC | PR_ADDR | PR_CAPATTACH, \ 1743 .pr_ctloutput = udp_ctloutput, \ 1744 .pr_abort = udp_abort, \ 1745 .pr_attach = udp_attach, \ 1746 .pr_bind = udp_bind, \ 1747 .pr_connect = udp_connect, \ 1748 .pr_control = in_control, \ 1749 .pr_detach = udp_detach, \ 1750 .pr_disconnect = udp_disconnect, \ 1751 .pr_peeraddr = in_getpeeraddr, \ 1752 .pr_send = udp_send, \ 1753 .pr_soreceive = soreceive_dgram, \ 1754 .pr_sosend = sosend_dgram, \ 1755 .pr_shutdown = udp_shutdown, \ 1756 .pr_sockaddr = in_getsockaddr, \ 1757 .pr_sosetlabel = in_pcbsosetlabel, \ 1758 .pr_close = udp_close 1759 1760 struct protosw udp_protosw = { 1761 .pr_protocol = IPPROTO_UDP, 1762 UDP_PROTOSW 1763 }; 1764 1765 struct protosw udplite_protosw = { 1766 .pr_protocol = IPPROTO_UDPLITE, 1767 UDP_PROTOSW 1768 }; 1769 1770 static void 1771 udp_init(void *arg __unused) 1772 { 1773 1774 IPPROTO_REGISTER(IPPROTO_UDP, udp_input, udp_ctlinput); 1775 IPPROTO_REGISTER(IPPROTO_UDPLITE, udp_input, udplite_ctlinput); 1776 } 1777 SYSINIT(udp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, udp_init, NULL); 1778 #endif /* INET */ 1779