1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 3 * The Regents of the University of California. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 4. Neither the name of the University nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95 31 * $FreeBSD$ 32 */ 33 34 #include "opt_ipfw.h" 35 #include "opt_ipsec.h" 36 #include "opt_inet6.h" 37 #include "opt_mac.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/domain.h> 42 #include <sys/eventhandler.h> 43 #include <sys/jail.h> 44 #include <sys/kernel.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/priv.h> 49 #include <sys/proc.h> 50 #include <sys/protosw.h> 51 #include <sys/signalvar.h> 52 #include <sys/socket.h> 53 #include <sys/socketvar.h> 54 #include <sys/sx.h> 55 #include <sys/sysctl.h> 56 #include <sys/syslog.h> 57 58 #include <vm/uma.h> 59 60 #include <net/if.h> 61 #include <net/route.h> 62 63 #include <netinet/in.h> 64 #include <netinet/in_systm.h> 65 #include <netinet/in_pcb.h> 66 #include <netinet/in_var.h> 67 #include <netinet/ip.h> 68 #ifdef INET6 69 #include <netinet/ip6.h> 70 #endif 71 #include <netinet/ip_icmp.h> 72 #include <netinet/icmp_var.h> 73 #include <netinet/ip_var.h> 74 #include <netinet/ip_options.h> 75 #ifdef INET6 76 #include <netinet6/ip6_var.h> 77 #endif 78 #include <netinet/udp.h> 79 #include <netinet/udp_var.h> 80 81 #ifdef FAST_IPSEC 82 #include <netipsec/ipsec.h> 83 #endif 84 85 #ifdef IPSEC 86 #include <netinet6/ipsec.h> 87 #endif 88 89 #include <machine/in_cksum.h> 90 91 #include <security/mac/mac_framework.h> 92 93 /* 94 * UDP protocol implementation. 95 * Per RFC 768, August, 1980. 96 */ 97 98 /* 99 * BSD 4.2 defaulted the udp checksum to be off. Turning off udp checksums 100 * removes the only data integrity mechanism for packets and malformed 101 * packets that would otherwise be discarded by bad checksums may cause 102 * problems (especially for NFS data blocks). 103 */ 104 static int udpcksum = 1; 105 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, &udpcksum, 106 0, ""); 107 108 int udp_log_in_vain = 0; 109 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW, 110 &udp_log_in_vain, 0, "Log all incoming UDP packets"); 111 112 static int blackhole = 0; 113 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW, &blackhole, 0, 114 "Do not send port unreachables for refused connects"); 115 116 static int strict_mcast_mship = 0; 117 SYSCTL_INT(_net_inet_udp, OID_AUTO, strict_mcast_mship, CTLFLAG_RW, 118 &strict_mcast_mship, 0, "Only send multicast to member sockets"); 119 120 struct inpcbhead udb; /* from udp_var.h */ 121 struct inpcbinfo udbinfo; 122 123 #ifndef UDBHASHSIZE 124 #define UDBHASHSIZE 16 125 #endif 126 127 struct udpstat udpstat; /* from udp_var.h */ 128 SYSCTL_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW, &udpstat, 129 udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)"); 130 131 static void udp_append(struct inpcb *last, struct ip *ip, struct mbuf *n, 132 int off, struct sockaddr_in *udp_in); 133 134 static void udp_detach(struct socket *so); 135 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 136 struct mbuf *, struct thread *); 137 138 static void 139 udp_zone_change(void *tag) 140 { 141 142 uma_zone_set_max(udbinfo.ipi_zone, maxsockets); 143 } 144 145 static int 146 udp_inpcb_init(void *mem, int size, int flags) 147 { 148 struct inpcb *inp = mem; 149 150 INP_LOCK_INIT(inp, "inp", "udpinp"); 151 return (0); 152 } 153 154 void 155 udp_init() 156 { 157 INP_INFO_LOCK_INIT(&udbinfo, "udp"); 158 LIST_INIT(&udb); 159 udbinfo.ipi_listhead = &udb; 160 udbinfo.ipi_hashbase = hashinit(UDBHASHSIZE, M_PCB, 161 &udbinfo.ipi_hashmask); 162 udbinfo.ipi_porthashbase = hashinit(UDBHASHSIZE, M_PCB, 163 &udbinfo.ipi_porthashmask); 164 udbinfo.ipi_zone = uma_zcreate("udpcb", sizeof(struct inpcb), NULL, 165 NULL, udp_inpcb_init, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 166 uma_zone_set_max(udbinfo.ipi_zone, maxsockets); 167 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL, 168 EVENTHANDLER_PRI_ANY); 169 } 170 171 void 172 udp_input(struct mbuf *m, int off) 173 { 174 int iphlen = off; 175 struct ip *ip; 176 struct udphdr *uh; 177 struct inpcb *inp; 178 int len; 179 struct ip save_ip; 180 struct sockaddr_in udp_in; 181 #ifdef IPFIREWALL_FORWARD 182 struct m_tag *fwd_tag; 183 #endif 184 185 udpstat.udps_ipackets++; 186 187 /* 188 * Strip IP options, if any; should skip this, make available to 189 * user, and use on returned packets, but we don't yet have a way to 190 * check the checksum with options still present. 191 */ 192 if (iphlen > sizeof (struct ip)) { 193 ip_stripoptions(m, (struct mbuf *)0); 194 iphlen = sizeof(struct ip); 195 } 196 197 /* 198 * Get IP and UDP header together in first mbuf. 199 */ 200 ip = mtod(m, struct ip *); 201 if (m->m_len < iphlen + sizeof(struct udphdr)) { 202 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 203 udpstat.udps_hdrops++; 204 return; 205 } 206 ip = mtod(m, struct ip *); 207 } 208 uh = (struct udphdr *)((caddr_t)ip + iphlen); 209 210 /* 211 * Destination port of 0 is illegal, based on RFC768. 212 */ 213 if (uh->uh_dport == 0) 214 goto badunlocked; 215 216 /* 217 * Construct sockaddr format source address. Stuff source address 218 * and datagram in user buffer. 219 */ 220 bzero(&udp_in, sizeof(udp_in)); 221 udp_in.sin_len = sizeof(udp_in); 222 udp_in.sin_family = AF_INET; 223 udp_in.sin_port = uh->uh_sport; 224 udp_in.sin_addr = ip->ip_src; 225 226 /* 227 * Make mbuf data length reflect UDP length. 228 * If not enough data to reflect UDP length, drop. 229 */ 230 len = ntohs((u_short)uh->uh_ulen); 231 if (ip->ip_len != len) { 232 if (len > ip->ip_len || len < sizeof(struct udphdr)) { 233 udpstat.udps_badlen++; 234 goto badunlocked; 235 } 236 m_adj(m, len - ip->ip_len); 237 /* ip->ip_len = len; */ 238 } 239 240 /* 241 * Save a copy of the IP header in case we want restore it for 242 * sending an ICMP error message in response. 243 */ 244 if (!blackhole) 245 save_ip = *ip; 246 247 /* 248 * Checksum extended UDP header and data. 249 */ 250 if (uh->uh_sum) { 251 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 252 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 253 uh->uh_sum = m->m_pkthdr.csum_data; 254 else 255 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, 256 ip->ip_dst.s_addr, htonl((u_short)len + 257 m->m_pkthdr.csum_data + IPPROTO_UDP)); 258 uh->uh_sum ^= 0xffff; 259 } else { 260 char b[9]; 261 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 262 bzero(((struct ipovly *)ip)->ih_x1, 9); 263 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 264 uh->uh_sum = in_cksum(m, len + sizeof (struct ip)); 265 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 266 } 267 if (uh->uh_sum) { 268 udpstat.udps_badsum++; 269 m_freem(m); 270 return; 271 } 272 } else 273 udpstat.udps_nosum++; 274 275 #ifdef IPFIREWALL_FORWARD 276 /* 277 * Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. 278 */ 279 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 280 if (fwd_tag != NULL) { 281 struct sockaddr_in *next_hop; 282 283 /* 284 * Do the hack. 285 */ 286 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 287 ip->ip_dst = next_hop->sin_addr; 288 uh->uh_dport = ntohs(next_hop->sin_port); 289 290 /* 291 * Remove the tag from the packet. We don't need it anymore. 292 */ 293 m_tag_delete(m, fwd_tag); 294 } 295 #endif 296 297 INP_INFO_RLOCK(&udbinfo); 298 299 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 300 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 301 struct inpcb *last; 302 303 /* 304 * Deliver a multicast or broadcast datagram to *all* sockets 305 * for which the local and remote addresses and ports match 306 * those of the incoming datagram. This allows more than one 307 * process to receive multi/broadcasts on the same port. 308 * (This really ought to be done for unicast datagrams as 309 * well, but that would cause problems with existing 310 * applications that open both address-specific sockets and a 311 * wildcard socket listening to the same port -- they would 312 * end up receiving duplicates of every unicast datagram. 313 * Those applications open the multiple sockets to overcome 314 * an inadequacy of the UDP socket interface, but for 315 * backwards compatibility we avoid the problem here rather 316 * than fixing the interface. Maybe 4.5BSD will remedy 317 * this?) 318 */ 319 last = NULL; 320 LIST_FOREACH(inp, &udb, inp_list) { 321 if (inp->inp_lport != uh->uh_dport) 322 continue; 323 #ifdef INET6 324 if ((inp->inp_vflag & INP_IPV4) == 0) 325 continue; 326 #endif 327 if (inp->inp_laddr.s_addr != INADDR_ANY) { 328 if (inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 329 continue; 330 } 331 if (inp->inp_faddr.s_addr != INADDR_ANY) { 332 if (inp->inp_faddr.s_addr != 333 ip->ip_src.s_addr || 334 inp->inp_fport != uh->uh_sport) 335 continue; 336 } 337 338 /* 339 * Check multicast packets to make sure they are only 340 * sent to sockets with multicast memberships for the 341 * packet's destination address and arrival interface 342 */ 343 #define MSHIP(_inp, n) ((_inp)->inp_moptions->imo_membership[(n)]) 344 #define NMSHIPS(_inp) ((_inp)->inp_moptions->imo_num_memberships) 345 INP_LOCK(inp); 346 if (strict_mcast_mship && inp->inp_moptions != NULL) { 347 int mship, foundmship = 0; 348 349 for (mship = 0; mship < NMSHIPS(inp); 350 mship++) { 351 if (MSHIP(inp, mship)->inm_addr.s_addr 352 == ip->ip_dst.s_addr && 353 MSHIP(inp, mship)->inm_ifp 354 == m->m_pkthdr.rcvif) { 355 foundmship = 1; 356 break; 357 } 358 } 359 if (foundmship == 0) { 360 INP_UNLOCK(inp); 361 continue; 362 } 363 } 364 #undef NMSHIPS 365 #undef MSHIP 366 if (last != NULL) { 367 struct mbuf *n; 368 369 n = m_copy(m, 0, M_COPYALL); 370 if (n != NULL) 371 udp_append(last, ip, n, iphlen + 372 sizeof(struct udphdr), &udp_in); 373 INP_UNLOCK(last); 374 } 375 last = inp; 376 /* 377 * Don't look for additional matches if this one does 378 * not have either the SO_REUSEPORT or SO_REUSEADDR 379 * socket options set. This heuristic avoids 380 * searching through all pcbs in the common case of a 381 * non-shared port. It assumes that an application 382 * will never clear these options after setting them. 383 */ 384 if ((last->inp_socket->so_options & 385 (SO_REUSEPORT|SO_REUSEADDR)) == 0) 386 break; 387 } 388 389 if (last == NULL) { 390 /* 391 * No matching pcb found; discard datagram. (No need 392 * to send an ICMP Port Unreachable for a broadcast 393 * or multicast datgram.) 394 */ 395 udpstat.udps_noportbcast++; 396 goto badheadlocked; 397 } 398 udp_append(last, ip, m, iphlen + sizeof(struct udphdr), 399 &udp_in); 400 INP_UNLOCK(last); 401 INP_INFO_RUNLOCK(&udbinfo); 402 return; 403 } 404 405 /* 406 * Locate pcb for datagram. 407 */ 408 inp = in_pcblookup_hash(&udbinfo, ip->ip_src, uh->uh_sport, 409 ip->ip_dst, uh->uh_dport, 1, m->m_pkthdr.rcvif); 410 if (inp == NULL) { 411 if (udp_log_in_vain) { 412 char buf[4*sizeof "123"]; 413 414 strcpy(buf, inet_ntoa(ip->ip_dst)); 415 log(LOG_INFO, 416 "Connection attempt to UDP %s:%d from %s:%d\n", 417 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 418 ntohs(uh->uh_sport)); 419 } 420 udpstat.udps_noport++; 421 if (m->m_flags & (M_BCAST | M_MCAST)) { 422 udpstat.udps_noportbcast++; 423 goto badheadlocked; 424 } 425 if (blackhole) 426 goto badheadlocked; 427 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 428 goto badheadlocked; 429 *ip = save_ip; 430 ip->ip_len += iphlen; 431 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 432 INP_INFO_RUNLOCK(&udbinfo); 433 return; 434 } 435 436 /* 437 * Check the minimum TTL for socket. 438 */ 439 INP_LOCK(inp); 440 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) 441 goto badheadlocked; 442 udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in); 443 INP_UNLOCK(inp); 444 INP_INFO_RUNLOCK(&udbinfo); 445 return; 446 447 badheadlocked: 448 if (inp) 449 INP_UNLOCK(inp); 450 INP_INFO_RUNLOCK(&udbinfo); 451 badunlocked: 452 m_freem(m); 453 } 454 455 /* 456 * Subroutine of udp_input(), which appends the provided mbuf chain to the 457 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 458 * contains the source address. If the socket ends up being an IPv6 socket, 459 * udp_append() will convert to a sockaddr_in6 before passing the address 460 * into the socket code. 461 */ 462 static void 463 udp_append(struct inpcb *inp, struct ip *ip, struct mbuf *n, int off, 464 struct sockaddr_in *udp_in) 465 { 466 struct sockaddr *append_sa; 467 struct socket *so; 468 struct mbuf *opts = 0; 469 #ifdef INET6 470 struct sockaddr_in6 udp_in6; 471 #endif 472 473 INP_LOCK_ASSERT(inp); 474 475 #if defined(IPSEC) || defined(FAST_IPSEC) 476 /* check AH/ESP integrity. */ 477 if (ipsec4_in_reject(n, inp)) { 478 #ifdef IPSEC 479 ipsecstat.in_polvio++; 480 #endif 481 m_freem(n); 482 return; 483 } 484 #endif /*IPSEC || FAST_IPSEC*/ 485 #ifdef MAC 486 if (mac_check_inpcb_deliver(inp, n) != 0) { 487 m_freem(n); 488 return; 489 } 490 #endif 491 if (inp->inp_flags & INP_CONTROLOPTS || 492 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 493 #ifdef INET6 494 if (inp->inp_vflag & INP_IPV6) { 495 int savedflags; 496 497 savedflags = inp->inp_flags; 498 inp->inp_flags &= ~INP_UNMAPPABLEOPTS; 499 ip6_savecontrol(inp, n, &opts); 500 inp->inp_flags = savedflags; 501 } else 502 #endif 503 ip_savecontrol(inp, &opts, ip, n); 504 } 505 #ifdef INET6 506 if (inp->inp_vflag & INP_IPV6) { 507 bzero(&udp_in6, sizeof(udp_in6)); 508 udp_in6.sin6_len = sizeof(udp_in6); 509 udp_in6.sin6_family = AF_INET6; 510 in6_sin_2_v4mapsin6(udp_in, &udp_in6); 511 append_sa = (struct sockaddr *)&udp_in6; 512 } else 513 #endif 514 append_sa = (struct sockaddr *)udp_in; 515 m_adj(n, off); 516 517 so = inp->inp_socket; 518 SOCKBUF_LOCK(&so->so_rcv); 519 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 520 m_freem(n); 521 if (opts) 522 m_freem(opts); 523 udpstat.udps_fullsock++; 524 SOCKBUF_UNLOCK(&so->so_rcv); 525 } else 526 sorwakeup_locked(so); 527 } 528 529 /* 530 * Notify a udp user of an asynchronous error; just wake up so that they can 531 * collect error status. 532 */ 533 struct inpcb * 534 udp_notify(struct inpcb *inp, int errno) 535 { 536 537 inp->inp_socket->so_error = errno; 538 sorwakeup(inp->inp_socket); 539 sowwakeup(inp->inp_socket); 540 return (inp); 541 } 542 543 void 544 udp_ctlinput(int cmd, struct sockaddr *sa, void *vip) 545 { 546 struct ip *ip = vip; 547 struct udphdr *uh; 548 struct inpcb *(*notify)(struct inpcb *, int) = udp_notify; 549 struct in_addr faddr; 550 struct inpcb *inp; 551 552 faddr = ((struct sockaddr_in *)sa)->sin_addr; 553 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 554 return; 555 556 /* 557 * Redirects don't need to be handled up here. 558 */ 559 if (PRC_IS_REDIRECT(cmd)) 560 return; 561 562 /* 563 * Hostdead is ugly because it goes linearly through all PCBs. 564 * 565 * XXX: We never get this from ICMP, otherwise it makes an excellent 566 * DoS attack on machines with many connections. 567 */ 568 if (cmd == PRC_HOSTDEAD) 569 ip = 0; 570 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 571 return; 572 if (ip) { 573 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 574 INP_INFO_RLOCK(&udbinfo); 575 inp = in_pcblookup_hash(&udbinfo, faddr, uh->uh_dport, 576 ip->ip_src, uh->uh_sport, 0, NULL); 577 if (inp != NULL) { 578 INP_LOCK(inp); 579 if (inp->inp_socket != NULL) { 580 (*notify)(inp, inetctlerrmap[cmd]); 581 } 582 INP_UNLOCK(inp); 583 } 584 INP_INFO_RUNLOCK(&udbinfo); 585 } else 586 in_pcbnotifyall(&udbinfo, faddr, inetctlerrmap[cmd], notify); 587 } 588 589 static int 590 udp_pcblist(SYSCTL_HANDLER_ARGS) 591 { 592 int error, i, n; 593 struct inpcb *inp, **inp_list; 594 inp_gen_t gencnt; 595 struct xinpgen xig; 596 597 /* 598 * The process of preparing the TCB list is too time-consuming and 599 * resource-intensive to repeat twice on every request. 600 */ 601 if (req->oldptr == 0) { 602 n = udbinfo.ipi_count; 603 req->oldidx = 2 * (sizeof xig) 604 + (n + n/8) * sizeof(struct xinpcb); 605 return (0); 606 } 607 608 if (req->newptr != 0) 609 return (EPERM); 610 611 /* 612 * OK, now we're committed to doing something. 613 */ 614 INP_INFO_RLOCK(&udbinfo); 615 gencnt = udbinfo.ipi_gencnt; 616 n = udbinfo.ipi_count; 617 INP_INFO_RUNLOCK(&udbinfo); 618 619 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 620 + n * sizeof(struct xinpcb)); 621 if (error != 0) 622 return (error); 623 624 xig.xig_len = sizeof xig; 625 xig.xig_count = n; 626 xig.xig_gen = gencnt; 627 xig.xig_sogen = so_gencnt; 628 error = SYSCTL_OUT(req, &xig, sizeof xig); 629 if (error) 630 return (error); 631 632 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 633 if (inp_list == 0) 634 return (ENOMEM); 635 636 INP_INFO_RLOCK(&udbinfo); 637 for (inp = LIST_FIRST(udbinfo.ipi_listhead), i = 0; inp && i < n; 638 inp = LIST_NEXT(inp, inp_list)) { 639 INP_LOCK(inp); 640 if (inp->inp_gencnt <= gencnt && 641 cr_canseesocket(req->td->td_ucred, inp->inp_socket) == 0) 642 inp_list[i++] = inp; 643 INP_UNLOCK(inp); 644 } 645 INP_INFO_RUNLOCK(&udbinfo); 646 n = i; 647 648 error = 0; 649 for (i = 0; i < n; i++) { 650 inp = inp_list[i]; 651 INP_LOCK(inp); 652 if (inp->inp_gencnt <= gencnt) { 653 struct xinpcb xi; 654 bzero(&xi, sizeof(xi)); 655 xi.xi_len = sizeof xi; 656 /* XXX should avoid extra copy */ 657 bcopy(inp, &xi.xi_inp, sizeof *inp); 658 if (inp->inp_socket) 659 sotoxsocket(inp->inp_socket, &xi.xi_socket); 660 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 661 INP_UNLOCK(inp); 662 error = SYSCTL_OUT(req, &xi, sizeof xi); 663 } else 664 INP_UNLOCK(inp); 665 } 666 if (!error) { 667 /* 668 * Give the user an updated idea of our state. If the 669 * generation differs from what we told her before, she knows 670 * that something happened while we were processing this 671 * request, and it might be necessary to retry. 672 */ 673 INP_INFO_RLOCK(&udbinfo); 674 xig.xig_gen = udbinfo.ipi_gencnt; 675 xig.xig_sogen = so_gencnt; 676 xig.xig_count = udbinfo.ipi_count; 677 INP_INFO_RUNLOCK(&udbinfo); 678 error = SYSCTL_OUT(req, &xig, sizeof xig); 679 } 680 free(inp_list, M_TEMP); 681 return (error); 682 } 683 684 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 685 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 686 687 static int 688 udp_getcred(SYSCTL_HANDLER_ARGS) 689 { 690 struct xucred xuc; 691 struct sockaddr_in addrs[2]; 692 struct inpcb *inp; 693 int error; 694 695 error = priv_check_cred(req->td->td_ucred, PRIV_NETINET_GETCRED, 696 SUSER_ALLOWJAIL); 697 if (error) 698 return (error); 699 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 700 if (error) 701 return (error); 702 INP_INFO_RLOCK(&udbinfo); 703 inp = in_pcblookup_hash(&udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 704 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL); 705 if (inp == NULL || inp->inp_socket == NULL) { 706 error = ENOENT; 707 goto out; 708 } 709 error = cr_canseesocket(req->td->td_ucred, inp->inp_socket); 710 if (error) 711 goto out; 712 cru2x(inp->inp_socket->so_cred, &xuc); 713 out: 714 INP_INFO_RUNLOCK(&udbinfo); 715 if (error == 0) 716 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 717 return (error); 718 } 719 720 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 721 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 722 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 723 724 static int 725 udp_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr, 726 struct mbuf *control, struct thread *td) 727 { 728 struct udpiphdr *ui; 729 int len = m->m_pkthdr.len; 730 struct in_addr faddr, laddr; 731 struct cmsghdr *cm; 732 struct sockaddr_in *sin, src; 733 int error = 0; 734 int ipflags; 735 u_short fport, lport; 736 int unlock_udbinfo; 737 738 /* 739 * udp_output() may need to temporarily bind or connect the current 740 * inpcb. As such, we don't know up front what inpcb locks we will 741 * need. Do any work to decide what is needed up front before 742 * acquiring locks. 743 */ 744 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 745 if (control) 746 m_freem(control); 747 m_freem(m); 748 return (EMSGSIZE); 749 } 750 751 src.sin_family = 0; 752 if (control != NULL) { 753 /* 754 * XXX: Currently, we assume all the optional information is 755 * stored in a single mbuf. 756 */ 757 if (control->m_next) { 758 m_freem(control); 759 m_freem(m); 760 return (EINVAL); 761 } 762 for (; control->m_len > 0; 763 control->m_data += CMSG_ALIGN(cm->cmsg_len), 764 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 765 cm = mtod(control, struct cmsghdr *); 766 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 || 767 cm->cmsg_len > control->m_len) { 768 error = EINVAL; 769 break; 770 } 771 if (cm->cmsg_level != IPPROTO_IP) 772 continue; 773 774 switch (cm->cmsg_type) { 775 case IP_SENDSRCADDR: 776 if (cm->cmsg_len != 777 CMSG_LEN(sizeof(struct in_addr))) { 778 error = EINVAL; 779 break; 780 } 781 bzero(&src, sizeof(src)); 782 src.sin_family = AF_INET; 783 src.sin_len = sizeof(src); 784 src.sin_port = inp->inp_lport; 785 src.sin_addr = *(struct in_addr *)CMSG_DATA(cm); 786 break; 787 default: 788 error = ENOPROTOOPT; 789 break; 790 } 791 if (error) 792 break; 793 } 794 m_freem(control); 795 } 796 if (error) { 797 m_freem(m); 798 return (error); 799 } 800 801 if (src.sin_family == AF_INET || addr != NULL) { 802 INP_INFO_WLOCK(&udbinfo); 803 unlock_udbinfo = 1; 804 } else 805 unlock_udbinfo = 0; 806 INP_LOCK(inp); 807 808 #ifdef MAC 809 mac_create_mbuf_from_inpcb(inp, m); 810 #endif 811 812 /* 813 * If the IP_SENDSRCADDR control message was specified, override the 814 * source address for this datagram. Its use is invalidated if the 815 * address thus specified is incomplete or clobbers other inpcbs. 816 */ 817 laddr = inp->inp_laddr; 818 lport = inp->inp_lport; 819 if (src.sin_family == AF_INET) { 820 if ((lport == 0) || 821 (laddr.s_addr == INADDR_ANY && 822 src.sin_addr.s_addr == INADDR_ANY)) { 823 error = EINVAL; 824 goto release; 825 } 826 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 827 &laddr.s_addr, &lport, td->td_ucred); 828 if (error) 829 goto release; 830 } 831 832 if (addr) { 833 sin = (struct sockaddr_in *)addr; 834 if (jailed(td->td_ucred)) 835 prison_remote_ip(td->td_ucred, 0, 836 &sin->sin_addr.s_addr); 837 if (inp->inp_faddr.s_addr != INADDR_ANY) { 838 error = EISCONN; 839 goto release; 840 } 841 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, &lport, 842 &faddr.s_addr, &fport, NULL, td->td_ucred); 843 if (error) 844 goto release; 845 846 /* Commit the local port if newly assigned. */ 847 if (inp->inp_laddr.s_addr == INADDR_ANY && 848 inp->inp_lport == 0) { 849 /* 850 * Remember addr if jailed, to prevent rebinding. 851 */ 852 if (jailed(td->td_ucred)) 853 inp->inp_laddr = laddr; 854 inp->inp_lport = lport; 855 if (in_pcbinshash(inp) != 0) { 856 inp->inp_lport = 0; 857 error = EAGAIN; 858 goto release; 859 } 860 inp->inp_flags |= INP_ANONPORT; 861 } 862 } else { 863 faddr = inp->inp_faddr; 864 fport = inp->inp_fport; 865 if (faddr.s_addr == INADDR_ANY) { 866 error = ENOTCONN; 867 goto release; 868 } 869 } 870 871 /* 872 * Calculate data length and get a mbuf for UDP, IP, and possible 873 * link-layer headers. Immediate slide the data pointer back forward 874 * since we won't use that space at this layer. 875 */ 876 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT); 877 if (m == NULL) { 878 error = ENOBUFS; 879 goto release; 880 } 881 m->m_data += max_linkhdr; 882 m->m_len -= max_linkhdr; 883 m->m_pkthdr.len -= max_linkhdr; 884 885 /* 886 * Fill in mbuf with extended UDP header and addresses and length put 887 * into network format. 888 */ 889 ui = mtod(m, struct udpiphdr *); 890 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 891 ui->ui_pr = IPPROTO_UDP; 892 ui->ui_src = laddr; 893 ui->ui_dst = faddr; 894 ui->ui_sport = lport; 895 ui->ui_dport = fport; 896 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 897 898 /* 899 * Set the Don't Fragment bit in the IP header. 900 */ 901 if (inp->inp_flags & INP_DONTFRAG) { 902 struct ip *ip; 903 904 ip = (struct ip *)&ui->ui_i; 905 ip->ip_off |= IP_DF; 906 } 907 908 ipflags = 0; 909 if (inp->inp_socket->so_options & SO_DONTROUTE) 910 ipflags |= IP_ROUTETOIF; 911 if (inp->inp_socket->so_options & SO_BROADCAST) 912 ipflags |= IP_ALLOWBROADCAST; 913 if (inp->inp_flags & INP_ONESBCAST) 914 ipflags |= IP_SENDONES; 915 916 /* 917 * Set up checksum and output datagram. 918 */ 919 if (udpcksum) { 920 if (inp->inp_flags & INP_ONESBCAST) 921 faddr.s_addr = INADDR_BROADCAST; 922 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 923 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 924 m->m_pkthdr.csum_flags = CSUM_UDP; 925 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 926 } else 927 ui->ui_sum = 0; 928 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 929 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 930 ((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */ 931 udpstat.udps_opackets++; 932 933 if (unlock_udbinfo) 934 INP_INFO_WUNLOCK(&udbinfo); 935 error = ip_output(m, inp->inp_options, NULL, ipflags, 936 inp->inp_moptions, inp); 937 INP_UNLOCK(inp); 938 return (error); 939 940 release: 941 INP_UNLOCK(inp); 942 if (unlock_udbinfo) 943 INP_INFO_WUNLOCK(&udbinfo); 944 m_freem(m); 945 return (error); 946 } 947 948 u_long udp_sendspace = 9216; /* really max datagram size */ 949 /* 40 1K datagrams */ 950 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 951 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 952 953 u_long udp_recvspace = 40 * (1024 + 954 #ifdef INET6 955 sizeof(struct sockaddr_in6) 956 #else 957 sizeof(struct sockaddr_in) 958 #endif 959 ); 960 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 961 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 962 963 static void 964 udp_abort(struct socket *so) 965 { 966 struct inpcb *inp; 967 968 inp = sotoinpcb(so); 969 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 970 INP_INFO_WLOCK(&udbinfo); 971 INP_LOCK(inp); 972 if (inp->inp_faddr.s_addr != INADDR_ANY) { 973 in_pcbdisconnect(inp); 974 inp->inp_laddr.s_addr = INADDR_ANY; 975 soisdisconnected(so); 976 } 977 INP_UNLOCK(inp); 978 INP_INFO_WUNLOCK(&udbinfo); 979 } 980 981 static int 982 udp_attach(struct socket *so, int proto, struct thread *td) 983 { 984 struct inpcb *inp; 985 int error; 986 987 inp = sotoinpcb(so); 988 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 989 error = soreserve(so, udp_sendspace, udp_recvspace); 990 if (error) 991 return (error); 992 INP_INFO_WLOCK(&udbinfo); 993 error = in_pcballoc(so, &udbinfo); 994 if (error) { 995 INP_INFO_WUNLOCK(&udbinfo); 996 return (error); 997 } 998 999 inp = (struct inpcb *)so->so_pcb; 1000 INP_INFO_WUNLOCK(&udbinfo); 1001 inp->inp_vflag |= INP_IPV4; 1002 inp->inp_ip_ttl = ip_defttl; 1003 INP_UNLOCK(inp); 1004 return (0); 1005 } 1006 1007 static int 1008 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1009 { 1010 struct inpcb *inp; 1011 int error; 1012 1013 inp = sotoinpcb(so); 1014 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1015 INP_INFO_WLOCK(&udbinfo); 1016 INP_LOCK(inp); 1017 error = in_pcbbind(inp, nam, td->td_ucred); 1018 INP_UNLOCK(inp); 1019 INP_INFO_WUNLOCK(&udbinfo); 1020 return (error); 1021 } 1022 1023 static void 1024 udp_close(struct socket *so) 1025 { 1026 struct inpcb *inp; 1027 1028 inp = sotoinpcb(so); 1029 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1030 INP_INFO_WLOCK(&udbinfo); 1031 INP_LOCK(inp); 1032 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1033 in_pcbdisconnect(inp); 1034 inp->inp_laddr.s_addr = INADDR_ANY; 1035 soisdisconnected(so); 1036 } 1037 INP_UNLOCK(inp); 1038 INP_INFO_WUNLOCK(&udbinfo); 1039 } 1040 1041 static int 1042 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1043 { 1044 struct inpcb *inp; 1045 int error; 1046 struct sockaddr_in *sin; 1047 1048 inp = sotoinpcb(so); 1049 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1050 INP_INFO_WLOCK(&udbinfo); 1051 INP_LOCK(inp); 1052 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1053 INP_UNLOCK(inp); 1054 INP_INFO_WUNLOCK(&udbinfo); 1055 return (EISCONN); 1056 } 1057 sin = (struct sockaddr_in *)nam; 1058 if (jailed(td->td_ucred)) 1059 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr); 1060 error = in_pcbconnect(inp, nam, td->td_ucred); 1061 if (error == 0) 1062 soisconnected(so); 1063 INP_UNLOCK(inp); 1064 INP_INFO_WUNLOCK(&udbinfo); 1065 return (error); 1066 } 1067 1068 static void 1069 udp_detach(struct socket *so) 1070 { 1071 struct inpcb *inp; 1072 1073 inp = sotoinpcb(so); 1074 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1075 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY, 1076 ("udp_detach: not disconnected")); 1077 INP_INFO_WLOCK(&udbinfo); 1078 INP_LOCK(inp); 1079 in_pcbdetach(inp); 1080 in_pcbfree(inp); 1081 INP_INFO_WUNLOCK(&udbinfo); 1082 } 1083 1084 static int 1085 udp_disconnect(struct socket *so) 1086 { 1087 struct inpcb *inp; 1088 1089 inp = sotoinpcb(so); 1090 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1091 INP_INFO_WLOCK(&udbinfo); 1092 INP_LOCK(inp); 1093 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1094 INP_INFO_WUNLOCK(&udbinfo); 1095 INP_UNLOCK(inp); 1096 return (ENOTCONN); 1097 } 1098 1099 in_pcbdisconnect(inp); 1100 inp->inp_laddr.s_addr = INADDR_ANY; 1101 SOCK_LOCK(so); 1102 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1103 SOCK_UNLOCK(so); 1104 INP_UNLOCK(inp); 1105 INP_INFO_WUNLOCK(&udbinfo); 1106 return (0); 1107 } 1108 1109 static int 1110 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1111 struct mbuf *control, struct thread *td) 1112 { 1113 struct inpcb *inp; 1114 1115 inp = sotoinpcb(so); 1116 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1117 return (udp_output(inp, m, addr, control, td)); 1118 } 1119 1120 int 1121 udp_shutdown(struct socket *so) 1122 { 1123 struct inpcb *inp; 1124 1125 inp = sotoinpcb(so); 1126 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1127 INP_LOCK(inp); 1128 socantsendmore(so); 1129 INP_UNLOCK(inp); 1130 return (0); 1131 } 1132 1133 /* 1134 * This is the wrapper function for in_setsockaddr. We just pass down the 1135 * pcbinfo for in_setsockaddr() to lock. We don't want to do the locking 1136 * here because in_setsockaddr() will call malloc and might block. 1137 */ 1138 static int 1139 udp_sockaddr(struct socket *so, struct sockaddr **nam) 1140 { 1141 1142 return (in_setsockaddr(so, nam)); 1143 } 1144 1145 /* 1146 * This is the wrapper function for in_setpeeraddr(). We just pass down the 1147 * pcbinfo for in_setpeeraddr() to lock. 1148 */ 1149 static int 1150 udp_peeraddr(struct socket *so, struct sockaddr **nam) 1151 { 1152 1153 return (in_setpeeraddr(so, nam)); 1154 } 1155 1156 struct pr_usrreqs udp_usrreqs = { 1157 .pru_abort = udp_abort, 1158 .pru_attach = udp_attach, 1159 .pru_bind = udp_bind, 1160 .pru_connect = udp_connect, 1161 .pru_control = in_control, 1162 .pru_detach = udp_detach, 1163 .pru_disconnect = udp_disconnect, 1164 .pru_peeraddr = udp_peeraddr, 1165 .pru_send = udp_send, 1166 .pru_sosend = sosend_dgram, 1167 .pru_shutdown = udp_shutdown, 1168 .pru_sockaddr = udp_sockaddr, 1169 .pru_sosetlabel = in_pcbsosetlabel, 1170 .pru_close = udp_close, 1171 }; 1172