1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)udp_usrreq.c 8.6 (Berkeley) 5/23/95 30 * $FreeBSD$ 31 */ 32 33 #include "opt_ipfw.h" 34 #include "opt_ipsec.h" 35 #include "opt_inet6.h" 36 #include "opt_mac.h" 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/domain.h> 41 #include <sys/jail.h> 42 #include <sys/kernel.h> 43 #include <sys/lock.h> 44 #include <sys/mac.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/proc.h> 48 #include <sys/protosw.h> 49 #include <sys/signalvar.h> 50 #include <sys/socket.h> 51 #include <sys/socketvar.h> 52 #include <sys/sx.h> 53 #include <sys/sysctl.h> 54 #include <sys/syslog.h> 55 56 #include <vm/uma.h> 57 58 #include <net/if.h> 59 #include <net/route.h> 60 61 #include <netinet/in.h> 62 #include <netinet/in_systm.h> 63 #include <netinet/in_pcb.h> 64 #include <netinet/in_var.h> 65 #include <netinet/ip.h> 66 #ifdef INET6 67 #include <netinet/ip6.h> 68 #endif 69 #include <netinet/ip_icmp.h> 70 #include <netinet/icmp_var.h> 71 #include <netinet/ip_var.h> 72 #include <netinet/ip_options.h> 73 #ifdef INET6 74 #include <netinet6/ip6_var.h> 75 #endif 76 #include <netinet/udp.h> 77 #include <netinet/udp_var.h> 78 79 #ifdef FAST_IPSEC 80 #include <netipsec/ipsec.h> 81 #endif /*FAST_IPSEC*/ 82 83 #ifdef IPSEC 84 #include <netinet6/ipsec.h> 85 #endif /*IPSEC*/ 86 87 #include <machine/in_cksum.h> 88 89 /* 90 * UDP protocol implementation. 91 * Per RFC 768, August, 1980. 92 */ 93 #ifndef COMPAT_42 94 static int udpcksum = 1; 95 #else 96 static int udpcksum = 0; /* XXX */ 97 #endif 98 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, 99 &udpcksum, 0, ""); 100 101 int log_in_vain = 0; 102 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW, 103 &log_in_vain, 0, "Log all incoming UDP packets"); 104 105 static int blackhole = 0; 106 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW, 107 &blackhole, 0, "Do not send port unreachables for refused connects"); 108 109 static int strict_mcast_mship = 0; 110 SYSCTL_INT(_net_inet_udp, OID_AUTO, strict_mcast_mship, CTLFLAG_RW, 111 &strict_mcast_mship, 0, "Only send multicast to member sockets"); 112 113 struct inpcbhead udb; /* from udp_var.h */ 114 #define udb6 udb /* for KAME src sync over BSD*'s */ 115 struct inpcbinfo udbinfo; 116 117 #ifndef UDBHASHSIZE 118 #define UDBHASHSIZE 16 119 #endif 120 121 struct udpstat udpstat; /* from udp_var.h */ 122 SYSCTL_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW, 123 &udpstat, udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)"); 124 125 static void udp_append(struct inpcb *last, struct ip *ip, struct mbuf *n, 126 int off, struct sockaddr_in *udp_in); 127 128 static void udp_detach(struct socket *so); 129 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 130 struct mbuf *, struct thread *); 131 132 void 133 udp_init() 134 { 135 INP_INFO_LOCK_INIT(&udbinfo, "udp"); 136 LIST_INIT(&udb); 137 udbinfo.listhead = &udb; 138 udbinfo.hashbase = hashinit(UDBHASHSIZE, M_PCB, &udbinfo.hashmask); 139 udbinfo.porthashbase = hashinit(UDBHASHSIZE, M_PCB, 140 &udbinfo.porthashmask); 141 udbinfo.ipi_zone = uma_zcreate("udpcb", sizeof(struct inpcb), NULL, 142 NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 143 uma_zone_set_max(udbinfo.ipi_zone, maxsockets); 144 } 145 146 void 147 udp_input(m, off) 148 register struct mbuf *m; 149 int off; 150 { 151 int iphlen = off; 152 register struct ip *ip; 153 register struct udphdr *uh; 154 register struct inpcb *inp; 155 int len; 156 struct ip save_ip; 157 struct sockaddr_in udp_in; 158 #ifdef IPFIREWALL_FORWARD 159 struct m_tag *fwd_tag; 160 #endif 161 162 udpstat.udps_ipackets++; 163 164 /* 165 * Strip IP options, if any; should skip this, 166 * make available to user, and use on returned packets, 167 * but we don't yet have a way to check the checksum 168 * with options still present. 169 */ 170 if (iphlen > sizeof (struct ip)) { 171 ip_stripoptions(m, (struct mbuf *)0); 172 iphlen = sizeof(struct ip); 173 } 174 175 /* 176 * Get IP and UDP header together in first mbuf. 177 */ 178 ip = mtod(m, struct ip *); 179 if (m->m_len < iphlen + sizeof(struct udphdr)) { 180 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 181 udpstat.udps_hdrops++; 182 return; 183 } 184 ip = mtod(m, struct ip *); 185 } 186 uh = (struct udphdr *)((caddr_t)ip + iphlen); 187 188 /* destination port of 0 is illegal, based on RFC768. */ 189 if (uh->uh_dport == 0) 190 goto badunlocked; 191 192 /* 193 * Construct sockaddr format source address. 194 * Stuff source address and datagram in user buffer. 195 */ 196 bzero(&udp_in, sizeof(udp_in)); 197 udp_in.sin_len = sizeof(udp_in); 198 udp_in.sin_family = AF_INET; 199 udp_in.sin_port = uh->uh_sport; 200 udp_in.sin_addr = ip->ip_src; 201 202 /* 203 * Make mbuf data length reflect UDP length. 204 * If not enough data to reflect UDP length, drop. 205 */ 206 len = ntohs((u_short)uh->uh_ulen); 207 if (ip->ip_len != len) { 208 if (len > ip->ip_len || len < sizeof(struct udphdr)) { 209 udpstat.udps_badlen++; 210 goto badunlocked; 211 } 212 m_adj(m, len - ip->ip_len); 213 /* ip->ip_len = len; */ 214 } 215 /* 216 * Save a copy of the IP header in case we want restore it 217 * for sending an ICMP error message in response. 218 */ 219 if (!blackhole) 220 save_ip = *ip; 221 222 /* 223 * Checksum extended UDP header and data. 224 */ 225 if (uh->uh_sum) { 226 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 227 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 228 uh->uh_sum = m->m_pkthdr.csum_data; 229 else 230 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, 231 ip->ip_dst.s_addr, htonl((u_short)len + 232 m->m_pkthdr.csum_data + IPPROTO_UDP)); 233 uh->uh_sum ^= 0xffff; 234 } else { 235 char b[9]; 236 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 237 bzero(((struct ipovly *)ip)->ih_x1, 9); 238 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 239 uh->uh_sum = in_cksum(m, len + sizeof (struct ip)); 240 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 241 } 242 if (uh->uh_sum) { 243 udpstat.udps_badsum++; 244 m_freem(m); 245 return; 246 } 247 } else 248 udpstat.udps_nosum++; 249 250 #ifdef IPFIREWALL_FORWARD 251 /* Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. */ 252 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 253 254 if (fwd_tag != NULL) { 255 struct sockaddr_in *next_hop; 256 257 /* Do the hack. */ 258 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 259 ip->ip_dst = next_hop->sin_addr; 260 uh->uh_dport = ntohs(next_hop->sin_port); 261 /* Remove the tag from the packet. We don't need it anymore. */ 262 m_tag_delete(m, fwd_tag); 263 } 264 #endif 265 266 INP_INFO_RLOCK(&udbinfo); 267 268 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 269 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 270 struct inpcb *last; 271 /* 272 * Deliver a multicast or broadcast datagram to *all* sockets 273 * for which the local and remote addresses and ports match 274 * those of the incoming datagram. This allows more than 275 * one process to receive multi/broadcasts on the same port. 276 * (This really ought to be done for unicast datagrams as 277 * well, but that would cause problems with existing 278 * applications that open both address-specific sockets and 279 * a wildcard socket listening to the same port -- they would 280 * end up receiving duplicates of every unicast datagram. 281 * Those applications open the multiple sockets to overcome an 282 * inadequacy of the UDP socket interface, but for backwards 283 * compatibility we avoid the problem here rather than 284 * fixing the interface. Maybe 4.5BSD will remedy this?) 285 */ 286 287 /* 288 * Locate pcb(s) for datagram. 289 * (Algorithm copied from raw_intr().) 290 */ 291 last = NULL; 292 LIST_FOREACH(inp, &udb, inp_list) { 293 if (inp->inp_lport != uh->uh_dport) 294 continue; 295 #ifdef INET6 296 if ((inp->inp_vflag & INP_IPV4) == 0) 297 continue; 298 #endif 299 if (inp->inp_laddr.s_addr != INADDR_ANY) { 300 if (inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 301 continue; 302 } 303 if (inp->inp_faddr.s_addr != INADDR_ANY) { 304 if (inp->inp_faddr.s_addr != 305 ip->ip_src.s_addr || 306 inp->inp_fport != uh->uh_sport) 307 continue; 308 } 309 INP_LOCK(inp); 310 311 /* 312 * Check multicast packets to make sure they are only 313 * sent to sockets with multicast memberships for the 314 * packet's destination address and arrival interface 315 */ 316 #define MSHIP(_inp, n) ((_inp)->inp_moptions->imo_membership[(n)]) 317 #define NMSHIPS(_inp) ((_inp)->inp_moptions->imo_num_memberships) 318 if (strict_mcast_mship && inp->inp_moptions != NULL) { 319 int mship, foundmship = 0; 320 321 for (mship = 0; mship < NMSHIPS(inp); mship++) { 322 if (MSHIP(inp, mship)->inm_addr.s_addr 323 == ip->ip_dst.s_addr && 324 MSHIP(inp, mship)->inm_ifp 325 == m->m_pkthdr.rcvif) { 326 foundmship = 1; 327 break; 328 } 329 } 330 if (foundmship == 0) { 331 INP_UNLOCK(inp); 332 continue; 333 } 334 } 335 #undef NMSHIPS 336 #undef MSHIP 337 if (last != NULL) { 338 struct mbuf *n; 339 340 n = m_copy(m, 0, M_COPYALL); 341 if (n != NULL) 342 udp_append(last, ip, n, 343 iphlen + 344 sizeof(struct udphdr), 345 &udp_in); 346 INP_UNLOCK(last); 347 } 348 last = inp; 349 /* 350 * Don't look for additional matches if this one does 351 * not have either the SO_REUSEPORT or SO_REUSEADDR 352 * socket options set. This heuristic avoids searching 353 * through all pcbs in the common case of a non-shared 354 * port. It * assumes that an application will never 355 * clear these options after setting them. 356 */ 357 if ((last->inp_socket->so_options&(SO_REUSEPORT|SO_REUSEADDR)) == 0) 358 break; 359 } 360 361 if (last == NULL) { 362 /* 363 * No matching pcb found; discard datagram. 364 * (No need to send an ICMP Port Unreachable 365 * for a broadcast or multicast datgram.) 366 */ 367 udpstat.udps_noportbcast++; 368 goto badheadlocked; 369 } 370 udp_append(last, ip, m, iphlen + sizeof(struct udphdr), 371 &udp_in); 372 INP_UNLOCK(last); 373 INP_INFO_RUNLOCK(&udbinfo); 374 return; 375 } 376 /* 377 * Locate pcb for datagram. 378 */ 379 inp = in_pcblookup_hash(&udbinfo, ip->ip_src, uh->uh_sport, 380 ip->ip_dst, uh->uh_dport, 1, m->m_pkthdr.rcvif); 381 if (inp == NULL) { 382 if (log_in_vain) { 383 char buf[4*sizeof "123"]; 384 385 strcpy(buf, inet_ntoa(ip->ip_dst)); 386 log(LOG_INFO, 387 "Connection attempt to UDP %s:%d from %s:%d\n", 388 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 389 ntohs(uh->uh_sport)); 390 } 391 udpstat.udps_noport++; 392 if (m->m_flags & (M_BCAST | M_MCAST)) { 393 udpstat.udps_noportbcast++; 394 goto badheadlocked; 395 } 396 if (blackhole) 397 goto badheadlocked; 398 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 399 goto badheadlocked; 400 *ip = save_ip; 401 ip->ip_len += iphlen; 402 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 403 INP_INFO_RUNLOCK(&udbinfo); 404 return; 405 } 406 INP_LOCK(inp); 407 /* Check the minimum TTL for socket. */ 408 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) 409 goto badheadlocked; 410 udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in); 411 INP_UNLOCK(inp); 412 INP_INFO_RUNLOCK(&udbinfo); 413 return; 414 415 badheadlocked: 416 if (inp) 417 INP_UNLOCK(inp); 418 INP_INFO_RUNLOCK(&udbinfo); 419 badunlocked: 420 m_freem(m); 421 return; 422 } 423 424 /* 425 * Subroutine of udp_input(), which appends the provided mbuf chain to the 426 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 427 * contains the source address. If the socket ends up being an IPv6 socket, 428 * udp_append() will convert to a sockaddr_in6 before passing the address 429 * into the socket code. 430 */ 431 static void 432 udp_append(last, ip, n, off, udp_in) 433 struct inpcb *last; 434 struct ip *ip; 435 struct mbuf *n; 436 int off; 437 struct sockaddr_in *udp_in; 438 { 439 struct sockaddr *append_sa; 440 struct socket *so; 441 struct mbuf *opts = 0; 442 #ifdef INET6 443 struct sockaddr_in6 udp_in6; 444 #endif 445 446 INP_LOCK_ASSERT(last); 447 448 #if defined(IPSEC) || defined(FAST_IPSEC) 449 /* check AH/ESP integrity. */ 450 if (ipsec4_in_reject(n, last)) { 451 #ifdef IPSEC 452 ipsecstat.in_polvio++; 453 #endif /*IPSEC*/ 454 m_freem(n); 455 return; 456 } 457 #endif /*IPSEC || FAST_IPSEC*/ 458 #ifdef MAC 459 if (mac_check_inpcb_deliver(last, n) != 0) { 460 m_freem(n); 461 return; 462 } 463 #endif 464 if (last->inp_flags & INP_CONTROLOPTS || 465 last->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 466 #ifdef INET6 467 if (last->inp_vflag & INP_IPV6) { 468 int savedflags; 469 470 savedflags = last->inp_flags; 471 last->inp_flags &= ~INP_UNMAPPABLEOPTS; 472 ip6_savecontrol(last, n, &opts); 473 last->inp_flags = savedflags; 474 } else 475 #endif 476 ip_savecontrol(last, &opts, ip, n); 477 } 478 #ifdef INET6 479 if (last->inp_vflag & INP_IPV6) { 480 bzero(&udp_in6, sizeof(udp_in6)); 481 udp_in6.sin6_len = sizeof(udp_in6); 482 udp_in6.sin6_family = AF_INET6; 483 in6_sin_2_v4mapsin6(udp_in, &udp_in6); 484 append_sa = (struct sockaddr *)&udp_in6; 485 } else 486 #endif 487 append_sa = (struct sockaddr *)udp_in; 488 m_adj(n, off); 489 490 so = last->inp_socket; 491 SOCKBUF_LOCK(&so->so_rcv); 492 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 493 m_freem(n); 494 if (opts) 495 m_freem(opts); 496 udpstat.udps_fullsock++; 497 SOCKBUF_UNLOCK(&so->so_rcv); 498 } else 499 sorwakeup_locked(so); 500 } 501 502 /* 503 * Notify a udp user of an asynchronous error; 504 * just wake up so that he can collect error status. 505 */ 506 struct inpcb * 507 udp_notify(inp, errno) 508 register struct inpcb *inp; 509 int errno; 510 { 511 inp->inp_socket->so_error = errno; 512 sorwakeup(inp->inp_socket); 513 sowwakeup(inp->inp_socket); 514 return inp; 515 } 516 517 void 518 udp_ctlinput(cmd, sa, vip) 519 int cmd; 520 struct sockaddr *sa; 521 void *vip; 522 { 523 struct ip *ip = vip; 524 struct udphdr *uh; 525 struct inpcb *(*notify)(struct inpcb *, int) = udp_notify; 526 struct in_addr faddr; 527 struct inpcb *inp; 528 529 faddr = ((struct sockaddr_in *)sa)->sin_addr; 530 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 531 return; 532 533 /* 534 * Redirects don't need to be handled up here. 535 */ 536 if (PRC_IS_REDIRECT(cmd)) 537 return; 538 /* 539 * Hostdead is ugly because it goes linearly through all PCBs. 540 * XXX: We never get this from ICMP, otherwise it makes an 541 * excellent DoS attack on machines with many connections. 542 */ 543 if (cmd == PRC_HOSTDEAD) 544 ip = 0; 545 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 546 return; 547 if (ip) { 548 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 549 INP_INFO_RLOCK(&udbinfo); 550 inp = in_pcblookup_hash(&udbinfo, faddr, uh->uh_dport, 551 ip->ip_src, uh->uh_sport, 0, NULL); 552 if (inp != NULL) { 553 INP_LOCK(inp); 554 if (inp->inp_socket != NULL) { 555 (*notify)(inp, inetctlerrmap[cmd]); 556 } 557 INP_UNLOCK(inp); 558 } 559 INP_INFO_RUNLOCK(&udbinfo); 560 } else 561 in_pcbnotifyall(&udbinfo, faddr, inetctlerrmap[cmd], notify); 562 } 563 564 static int 565 udp_pcblist(SYSCTL_HANDLER_ARGS) 566 { 567 int error, i, n; 568 struct inpcb *inp, **inp_list; 569 inp_gen_t gencnt; 570 struct xinpgen xig; 571 572 /* 573 * The process of preparing the TCB list is too time-consuming and 574 * resource-intensive to repeat twice on every request. 575 */ 576 if (req->oldptr == 0) { 577 n = udbinfo.ipi_count; 578 req->oldidx = 2 * (sizeof xig) 579 + (n + n/8) * sizeof(struct xinpcb); 580 return 0; 581 } 582 583 if (req->newptr != 0) 584 return EPERM; 585 586 /* 587 * OK, now we're committed to doing something. 588 */ 589 INP_INFO_RLOCK(&udbinfo); 590 gencnt = udbinfo.ipi_gencnt; 591 n = udbinfo.ipi_count; 592 INP_INFO_RUNLOCK(&udbinfo); 593 594 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 595 + n * sizeof(struct xinpcb)); 596 if (error != 0) 597 return (error); 598 599 xig.xig_len = sizeof xig; 600 xig.xig_count = n; 601 xig.xig_gen = gencnt; 602 xig.xig_sogen = so_gencnt; 603 error = SYSCTL_OUT(req, &xig, sizeof xig); 604 if (error) 605 return error; 606 607 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 608 if (inp_list == 0) 609 return ENOMEM; 610 611 INP_INFO_RLOCK(&udbinfo); 612 for (inp = LIST_FIRST(udbinfo.listhead), i = 0; inp && i < n; 613 inp = LIST_NEXT(inp, inp_list)) { 614 INP_LOCK(inp); 615 if (inp->inp_gencnt <= gencnt && 616 cr_canseesocket(req->td->td_ucred, inp->inp_socket) == 0) 617 inp_list[i++] = inp; 618 INP_UNLOCK(inp); 619 } 620 INP_INFO_RUNLOCK(&udbinfo); 621 n = i; 622 623 error = 0; 624 for (i = 0; i < n; i++) { 625 inp = inp_list[i]; 626 if (inp->inp_gencnt <= gencnt) { 627 struct xinpcb xi; 628 bzero(&xi, sizeof(xi)); 629 xi.xi_len = sizeof xi; 630 /* XXX should avoid extra copy */ 631 bcopy(inp, &xi.xi_inp, sizeof *inp); 632 if (inp->inp_socket) 633 sotoxsocket(inp->inp_socket, &xi.xi_socket); 634 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 635 error = SYSCTL_OUT(req, &xi, sizeof xi); 636 } 637 } 638 if (!error) { 639 /* 640 * Give the user an updated idea of our state. 641 * If the generation differs from what we told 642 * her before, she knows that something happened 643 * while we were processing this request, and it 644 * might be necessary to retry. 645 */ 646 INP_INFO_RLOCK(&udbinfo); 647 xig.xig_gen = udbinfo.ipi_gencnt; 648 xig.xig_sogen = so_gencnt; 649 xig.xig_count = udbinfo.ipi_count; 650 INP_INFO_RUNLOCK(&udbinfo); 651 error = SYSCTL_OUT(req, &xig, sizeof xig); 652 } 653 free(inp_list, M_TEMP); 654 return error; 655 } 656 657 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 658 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 659 660 static int 661 udp_getcred(SYSCTL_HANDLER_ARGS) 662 { 663 struct xucred xuc; 664 struct sockaddr_in addrs[2]; 665 struct inpcb *inp; 666 int error; 667 668 error = suser_cred(req->td->td_ucred, SUSER_ALLOWJAIL); 669 if (error) 670 return (error); 671 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 672 if (error) 673 return (error); 674 INP_INFO_RLOCK(&udbinfo); 675 inp = in_pcblookup_hash(&udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 676 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL); 677 if (inp == NULL || inp->inp_socket == NULL) { 678 error = ENOENT; 679 goto out; 680 } 681 error = cr_canseesocket(req->td->td_ucred, inp->inp_socket); 682 if (error) 683 goto out; 684 cru2x(inp->inp_socket->so_cred, &xuc); 685 out: 686 INP_INFO_RUNLOCK(&udbinfo); 687 if (error == 0) 688 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 689 return (error); 690 } 691 692 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 693 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 694 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 695 696 static int 697 udp_output(inp, m, addr, control, td) 698 register struct inpcb *inp; 699 struct mbuf *m; 700 struct sockaddr *addr; 701 struct mbuf *control; 702 struct thread *td; 703 { 704 register struct udpiphdr *ui; 705 register int len = m->m_pkthdr.len; 706 struct in_addr faddr, laddr; 707 struct cmsghdr *cm; 708 struct sockaddr_in *sin, src; 709 int error = 0; 710 int ipflags; 711 u_short fport, lport; 712 int unlock_udbinfo; 713 714 /* 715 * udp_output() may need to temporarily bind or connect the current 716 * inpcb. As such, we don't know up front what inpcb locks we will 717 * need. Do any work to decide what is needed up front before 718 * acquiring locks. 719 */ 720 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 721 if (control) 722 m_freem(control); 723 m_freem(m); 724 return EMSGSIZE; 725 } 726 727 src.sin_addr.s_addr = INADDR_ANY; 728 if (control != NULL) { 729 /* 730 * XXX: Currently, we assume all the optional information 731 * is stored in a single mbuf. 732 */ 733 if (control->m_next) { 734 m_freem(control); 735 m_freem(m); 736 return EINVAL; 737 } 738 for (; control->m_len > 0; 739 control->m_data += CMSG_ALIGN(cm->cmsg_len), 740 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 741 cm = mtod(control, struct cmsghdr *); 742 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 || 743 cm->cmsg_len > control->m_len) { 744 error = EINVAL; 745 break; 746 } 747 if (cm->cmsg_level != IPPROTO_IP) 748 continue; 749 750 switch (cm->cmsg_type) { 751 case IP_SENDSRCADDR: 752 if (cm->cmsg_len != 753 CMSG_LEN(sizeof(struct in_addr))) { 754 error = EINVAL; 755 break; 756 } 757 bzero(&src, sizeof(src)); 758 src.sin_family = AF_INET; 759 src.sin_len = sizeof(src); 760 src.sin_port = inp->inp_lport; 761 src.sin_addr = *(struct in_addr *)CMSG_DATA(cm); 762 break; 763 default: 764 error = ENOPROTOOPT; 765 break; 766 } 767 if (error) 768 break; 769 } 770 m_freem(control); 771 } 772 if (error) { 773 m_freem(m); 774 return error; 775 } 776 777 if (src.sin_addr.s_addr != INADDR_ANY || 778 addr != NULL) { 779 INP_INFO_WLOCK(&udbinfo); 780 unlock_udbinfo = 1; 781 } else 782 unlock_udbinfo = 0; 783 INP_LOCK(inp); 784 785 #ifdef MAC 786 mac_create_mbuf_from_inpcb(inp, m); 787 #endif 788 789 laddr = inp->inp_laddr; 790 lport = inp->inp_lport; 791 if (src.sin_addr.s_addr != INADDR_ANY) { 792 if (lport == 0) { 793 error = EINVAL; 794 goto release; 795 } 796 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 797 &laddr.s_addr, &lport, td->td_ucred); 798 if (error) 799 goto release; 800 } 801 802 if (addr) { 803 sin = (struct sockaddr_in *)addr; 804 if (jailed(td->td_ucred)) 805 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr); 806 if (inp->inp_faddr.s_addr != INADDR_ANY) { 807 error = EISCONN; 808 goto release; 809 } 810 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, &lport, 811 &faddr.s_addr, &fport, NULL, td->td_ucred); 812 if (error) 813 goto release; 814 815 /* Commit the local port if newly assigned. */ 816 if (inp->inp_laddr.s_addr == INADDR_ANY && 817 inp->inp_lport == 0) { 818 /* 819 * Remember addr if jailed, to prevent rebinding. 820 */ 821 if (jailed(td->td_ucred)) 822 inp->inp_laddr = laddr; 823 inp->inp_lport = lport; 824 if (in_pcbinshash(inp) != 0) { 825 inp->inp_lport = 0; 826 error = EAGAIN; 827 goto release; 828 } 829 inp->inp_flags |= INP_ANONPORT; 830 } 831 } else { 832 faddr = inp->inp_faddr; 833 fport = inp->inp_fport; 834 if (faddr.s_addr == INADDR_ANY) { 835 error = ENOTCONN; 836 goto release; 837 } 838 } 839 840 /* 841 * Calculate data length and get a mbuf for UDP, IP, and possible 842 * link-layer headers. Immediate slide the data pointer back forward 843 * since we won't use that space at this layer. 844 */ 845 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT); 846 if (m == NULL) { 847 error = ENOBUFS; 848 goto release; 849 } 850 m->m_data += max_linkhdr; 851 m->m_len -= max_linkhdr; 852 m->m_pkthdr.len -= max_linkhdr; 853 854 /* 855 * Fill in mbuf with extended UDP header 856 * and addresses and length put into network format. 857 */ 858 ui = mtod(m, struct udpiphdr *); 859 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 860 ui->ui_pr = IPPROTO_UDP; 861 ui->ui_src = laddr; 862 ui->ui_dst = faddr; 863 ui->ui_sport = lport; 864 ui->ui_dport = fport; 865 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 866 867 /* 868 * Set the Don't Fragment bit in the IP header. 869 */ 870 if (inp->inp_flags & INP_DONTFRAG) { 871 struct ip *ip; 872 ip = (struct ip *)&ui->ui_i; 873 ip->ip_off |= IP_DF; 874 } 875 876 ipflags = 0; 877 if (inp->inp_socket->so_options & SO_DONTROUTE) 878 ipflags |= IP_ROUTETOIF; 879 if (inp->inp_socket->so_options & SO_BROADCAST) 880 ipflags |= IP_ALLOWBROADCAST; 881 if (inp->inp_vflag & INP_ONESBCAST) 882 ipflags |= IP_SENDONES; 883 884 /* 885 * Set up checksum and output datagram. 886 */ 887 if (udpcksum) { 888 if (inp->inp_vflag & INP_ONESBCAST) 889 faddr.s_addr = INADDR_BROADCAST; 890 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 891 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 892 m->m_pkthdr.csum_flags = CSUM_UDP; 893 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 894 } else { 895 ui->ui_sum = 0; 896 } 897 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 898 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 899 ((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */ 900 udpstat.udps_opackets++; 901 902 if (unlock_udbinfo) 903 INP_INFO_WUNLOCK(&udbinfo); 904 error = ip_output(m, inp->inp_options, NULL, ipflags, 905 inp->inp_moptions, inp); 906 INP_UNLOCK(inp); 907 return (error); 908 909 release: 910 INP_UNLOCK(inp); 911 if (unlock_udbinfo) 912 INP_INFO_WUNLOCK(&udbinfo); 913 m_freem(m); 914 return (error); 915 } 916 917 u_long udp_sendspace = 9216; /* really max datagram size */ 918 /* 40 1K datagrams */ 919 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 920 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 921 922 u_long udp_recvspace = 40 * (1024 + 923 #ifdef INET6 924 sizeof(struct sockaddr_in6) 925 #else 926 sizeof(struct sockaddr_in) 927 #endif 928 ); 929 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 930 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 931 932 static void 933 udp_abort(struct socket *so) 934 { 935 struct inpcb *inp; 936 937 inp = sotoinpcb(so); 938 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 939 INP_INFO_WLOCK(&udbinfo); 940 INP_LOCK(inp); 941 soisdisconnected(so); 942 in_pcbdetach(inp); 943 in_pcbfree(inp); 944 INP_INFO_WUNLOCK(&udbinfo); 945 } 946 947 static int 948 udp_attach(struct socket *so, int proto, struct thread *td) 949 { 950 struct inpcb *inp; 951 int error; 952 953 inp = sotoinpcb(so); 954 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 955 INP_INFO_WLOCK(&udbinfo); 956 error = soreserve(so, udp_sendspace, udp_recvspace); 957 if (error) { 958 INP_INFO_WUNLOCK(&udbinfo); 959 return error; 960 } 961 error = in_pcballoc(so, &udbinfo, "udpinp"); 962 if (error) { 963 INP_INFO_WUNLOCK(&udbinfo); 964 return error; 965 } 966 967 inp = (struct inpcb *)so->so_pcb; 968 INP_LOCK(inp); 969 INP_INFO_WUNLOCK(&udbinfo); 970 inp->inp_vflag |= INP_IPV4; 971 inp->inp_ip_ttl = ip_defttl; 972 INP_UNLOCK(inp); 973 return 0; 974 } 975 976 static int 977 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 978 { 979 struct inpcb *inp; 980 int error; 981 982 inp = sotoinpcb(so); 983 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 984 INP_INFO_WLOCK(&udbinfo); 985 INP_LOCK(inp); 986 error = in_pcbbind(inp, nam, td->td_ucred); 987 INP_UNLOCK(inp); 988 INP_INFO_WUNLOCK(&udbinfo); 989 return error; 990 } 991 992 static int 993 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 994 { 995 struct inpcb *inp; 996 int error; 997 struct sockaddr_in *sin; 998 999 inp = sotoinpcb(so); 1000 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1001 INP_INFO_WLOCK(&udbinfo); 1002 INP_LOCK(inp); 1003 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1004 INP_UNLOCK(inp); 1005 INP_INFO_WUNLOCK(&udbinfo); 1006 return EISCONN; 1007 } 1008 sin = (struct sockaddr_in *)nam; 1009 if (jailed(td->td_ucred)) 1010 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr); 1011 error = in_pcbconnect(inp, nam, td->td_ucred); 1012 if (error == 0) 1013 soisconnected(so); 1014 INP_UNLOCK(inp); 1015 INP_INFO_WUNLOCK(&udbinfo); 1016 return error; 1017 } 1018 1019 static void 1020 udp_detach(struct socket *so) 1021 { 1022 struct inpcb *inp; 1023 1024 inp = sotoinpcb(so); 1025 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1026 INP_INFO_WLOCK(&udbinfo); 1027 INP_LOCK(inp); 1028 in_pcbdetach(inp); 1029 in_pcbfree(inp); 1030 INP_INFO_WUNLOCK(&udbinfo); 1031 } 1032 1033 static int 1034 udp_disconnect(struct socket *so) 1035 { 1036 struct inpcb *inp; 1037 1038 inp = sotoinpcb(so); 1039 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1040 INP_INFO_WLOCK(&udbinfo); 1041 INP_LOCK(inp); 1042 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1043 INP_INFO_WUNLOCK(&udbinfo); 1044 INP_UNLOCK(inp); 1045 return ENOTCONN; 1046 } 1047 1048 in_pcbdisconnect(inp); 1049 inp->inp_laddr.s_addr = INADDR_ANY; 1050 INP_UNLOCK(inp); 1051 INP_INFO_WUNLOCK(&udbinfo); 1052 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1053 return 0; 1054 } 1055 1056 static int 1057 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1058 struct mbuf *control, struct thread *td) 1059 { 1060 struct inpcb *inp; 1061 1062 inp = sotoinpcb(so); 1063 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1064 return udp_output(inp, m, addr, control, td); 1065 } 1066 1067 int 1068 udp_shutdown(struct socket *so) 1069 { 1070 struct inpcb *inp; 1071 1072 inp = sotoinpcb(so); 1073 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1074 INP_LOCK(inp); 1075 socantsendmore(so); 1076 INP_UNLOCK(inp); 1077 return 0; 1078 } 1079 1080 /* 1081 * This is the wrapper function for in_setsockaddr. We just pass down 1082 * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking 1083 * here because in_setsockaddr will call malloc and might block. 1084 */ 1085 static int 1086 udp_sockaddr(struct socket *so, struct sockaddr **nam) 1087 { 1088 return (in_setsockaddr(so, nam, &udbinfo)); 1089 } 1090 1091 /* 1092 * This is the wrapper function for in_setpeeraddr. We just pass down 1093 * the pcbinfo for in_setpeeraddr to lock. 1094 */ 1095 static int 1096 udp_peeraddr(struct socket *so, struct sockaddr **nam) 1097 { 1098 return (in_setpeeraddr(so, nam, &udbinfo)); 1099 } 1100 1101 struct pr_usrreqs udp_usrreqs = { 1102 .pru_abort = udp_abort, 1103 .pru_attach = udp_attach, 1104 .pru_bind = udp_bind, 1105 .pru_connect = udp_connect, 1106 .pru_control = in_control, 1107 .pru_detach = udp_detach, 1108 .pru_disconnect = udp_disconnect, 1109 .pru_peeraddr = udp_peeraddr, 1110 .pru_send = udp_send, 1111 .pru_shutdown = udp_shutdown, 1112 .pru_sockaddr = udp_sockaddr, 1113 .pru_sosetlabel = in_pcbsosetlabel 1114 }; 1115