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