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/eventhandler.h> 42 #include <sys/jail.h> 43 #include <sys/kernel.h> 44 #include <sys/lock.h> 45 #include <sys/mac.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/proc.h> 49 #include <sys/protosw.h> 50 #include <sys/signalvar.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/sx.h> 54 #include <sys/sysctl.h> 55 #include <sys/syslog.h> 56 57 #include <vm/uma.h> 58 59 #include <net/if.h> 60 #include <net/route.h> 61 62 #include <netinet/in.h> 63 #include <netinet/in_systm.h> 64 #include <netinet/in_pcb.h> 65 #include <netinet/in_var.h> 66 #include <netinet/ip.h> 67 #ifdef INET6 68 #include <netinet/ip6.h> 69 #endif 70 #include <netinet/ip_icmp.h> 71 #include <netinet/icmp_var.h> 72 #include <netinet/ip_var.h> 73 #include <netinet/ip_options.h> 74 #ifdef INET6 75 #include <netinet6/ip6_var.h> 76 #endif 77 #include <netinet/udp.h> 78 #include <netinet/udp_var.h> 79 80 #ifdef FAST_IPSEC 81 #include <netipsec/ipsec.h> 82 #endif /*FAST_IPSEC*/ 83 84 #ifdef IPSEC 85 #include <netinet6/ipsec.h> 86 #endif /*IPSEC*/ 87 88 #include <machine/in_cksum.h> 89 90 /* 91 * UDP protocol implementation. 92 * Per RFC 768, August, 1980. 93 */ 94 #ifndef COMPAT_42 95 static int udpcksum = 1; 96 #else 97 static int udpcksum = 0; /* XXX */ 98 #endif 99 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, 100 &udpcksum, 0, ""); 101 102 int log_in_vain = 0; 103 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW, 104 &log_in_vain, 0, "Log all incoming UDP packets"); 105 106 static int blackhole = 0; 107 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW, 108 &blackhole, 0, "Do not send port unreachables for refused connects"); 109 110 static int strict_mcast_mship = 0; 111 SYSCTL_INT(_net_inet_udp, OID_AUTO, strict_mcast_mship, CTLFLAG_RW, 112 &strict_mcast_mship, 0, "Only send multicast to member sockets"); 113 114 struct inpcbhead udb; /* from udp_var.h */ 115 #define udb6 udb /* for KAME src sync over BSD*'s */ 116 struct inpcbinfo udbinfo; 117 118 #ifndef UDBHASHSIZE 119 #define UDBHASHSIZE 16 120 #endif 121 122 struct udpstat udpstat; /* from udp_var.h */ 123 SYSCTL_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW, 124 &udpstat, udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)"); 125 126 static void udp_append(struct inpcb *last, struct ip *ip, struct mbuf *n, 127 int off, struct sockaddr_in *udp_in); 128 129 static void udp_detach(struct socket *so); 130 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 131 struct mbuf *, struct thread *); 132 133 static void 134 udp_zone_change(void *tag) 135 { 136 137 uma_zone_set_max(udbinfo.ipi_zone, maxsockets); 138 } 139 140 void 141 udp_init() 142 { 143 INP_INFO_LOCK_INIT(&udbinfo, "udp"); 144 LIST_INIT(&udb); 145 udbinfo.listhead = &udb; 146 udbinfo.hashbase = hashinit(UDBHASHSIZE, M_PCB, &udbinfo.hashmask); 147 udbinfo.porthashbase = hashinit(UDBHASHSIZE, M_PCB, 148 &udbinfo.porthashmask); 149 udbinfo.ipi_zone = uma_zcreate("udpcb", sizeof(struct inpcb), NULL, 150 NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 151 uma_zone_set_max(udbinfo.ipi_zone, maxsockets); 152 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL, 153 EVENTHANDLER_PRI_ANY); 154 } 155 156 void 157 udp_input(m, off) 158 register struct mbuf *m; 159 int off; 160 { 161 int iphlen = off; 162 register struct ip *ip; 163 register struct udphdr *uh; 164 register struct inpcb *inp; 165 int len; 166 struct ip save_ip; 167 struct sockaddr_in udp_in; 168 #ifdef IPFIREWALL_FORWARD 169 struct m_tag *fwd_tag; 170 #endif 171 172 udpstat.udps_ipackets++; 173 174 /* 175 * Strip IP options, if any; should skip this, 176 * make available to user, and use on returned packets, 177 * but we don't yet have a way to check the checksum 178 * with options still present. 179 */ 180 if (iphlen > sizeof (struct ip)) { 181 ip_stripoptions(m, (struct mbuf *)0); 182 iphlen = sizeof(struct ip); 183 } 184 185 /* 186 * Get IP and UDP header together in first mbuf. 187 */ 188 ip = mtod(m, struct ip *); 189 if (m->m_len < iphlen + sizeof(struct udphdr)) { 190 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 191 udpstat.udps_hdrops++; 192 return; 193 } 194 ip = mtod(m, struct ip *); 195 } 196 uh = (struct udphdr *)((caddr_t)ip + iphlen); 197 198 /* destination port of 0 is illegal, based on RFC768. */ 199 if (uh->uh_dport == 0) 200 goto badunlocked; 201 202 /* 203 * Construct sockaddr format source address. 204 * Stuff source address and datagram in user buffer. 205 */ 206 bzero(&udp_in, sizeof(udp_in)); 207 udp_in.sin_len = sizeof(udp_in); 208 udp_in.sin_family = AF_INET; 209 udp_in.sin_port = uh->uh_sport; 210 udp_in.sin_addr = ip->ip_src; 211 212 /* 213 * Make mbuf data length reflect UDP length. 214 * If not enough data to reflect UDP length, drop. 215 */ 216 len = ntohs((u_short)uh->uh_ulen); 217 if (ip->ip_len != len) { 218 if (len > ip->ip_len || len < sizeof(struct udphdr)) { 219 udpstat.udps_badlen++; 220 goto badunlocked; 221 } 222 m_adj(m, len - ip->ip_len); 223 /* ip->ip_len = len; */ 224 } 225 /* 226 * Save a copy of the IP header in case we want restore it 227 * for sending an ICMP error message in response. 228 */ 229 if (!blackhole) 230 save_ip = *ip; 231 232 /* 233 * Checksum extended UDP header and data. 234 */ 235 if (uh->uh_sum) { 236 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 237 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 238 uh->uh_sum = m->m_pkthdr.csum_data; 239 else 240 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, 241 ip->ip_dst.s_addr, htonl((u_short)len + 242 m->m_pkthdr.csum_data + IPPROTO_UDP)); 243 uh->uh_sum ^= 0xffff; 244 } else { 245 char b[9]; 246 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 247 bzero(((struct ipovly *)ip)->ih_x1, 9); 248 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 249 uh->uh_sum = in_cksum(m, len + sizeof (struct ip)); 250 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 251 } 252 if (uh->uh_sum) { 253 udpstat.udps_badsum++; 254 m_freem(m); 255 return; 256 } 257 } else 258 udpstat.udps_nosum++; 259 260 #ifdef IPFIREWALL_FORWARD 261 /* Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. */ 262 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 263 264 if (fwd_tag != NULL) { 265 struct sockaddr_in *next_hop; 266 267 /* Do the hack. */ 268 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 269 ip->ip_dst = next_hop->sin_addr; 270 uh->uh_dport = ntohs(next_hop->sin_port); 271 /* Remove the tag from the packet. We don't need it anymore. */ 272 m_tag_delete(m, fwd_tag); 273 } 274 #endif 275 276 INP_INFO_RLOCK(&udbinfo); 277 278 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 279 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 280 struct inpcb *last; 281 /* 282 * Deliver a multicast or broadcast datagram to *all* sockets 283 * for which the local and remote addresses and ports match 284 * those of the incoming datagram. This allows more than 285 * one process to receive multi/broadcasts on the same port. 286 * (This really ought to be done for unicast datagrams as 287 * well, but that would cause problems with existing 288 * applications that open both address-specific sockets and 289 * a wildcard socket listening to the same port -- they would 290 * end up receiving duplicates of every unicast datagram. 291 * Those applications open the multiple sockets to overcome an 292 * inadequacy of the UDP socket interface, but for backwards 293 * compatibility we avoid the problem here rather than 294 * fixing the interface. Maybe 4.5BSD will remedy this?) 295 */ 296 297 /* 298 * Locate pcb(s) for datagram. 299 * (Algorithm copied from raw_intr().) 300 */ 301 last = NULL; 302 LIST_FOREACH(inp, &udb, inp_list) { 303 if (inp->inp_lport != uh->uh_dport) 304 continue; 305 #ifdef INET6 306 if ((inp->inp_vflag & INP_IPV4) == 0) 307 continue; 308 #endif 309 if (inp->inp_laddr.s_addr != INADDR_ANY) { 310 if (inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 311 continue; 312 } 313 if (inp->inp_faddr.s_addr != INADDR_ANY) { 314 if (inp->inp_faddr.s_addr != 315 ip->ip_src.s_addr || 316 inp->inp_fport != uh->uh_sport) 317 continue; 318 } 319 INP_LOCK(inp); 320 321 /* 322 * Check multicast packets to make sure they are only 323 * sent to sockets with multicast memberships for the 324 * packet's destination address and arrival interface 325 */ 326 #define MSHIP(_inp, n) ((_inp)->inp_moptions->imo_membership[(n)]) 327 #define NMSHIPS(_inp) ((_inp)->inp_moptions->imo_num_memberships) 328 if (strict_mcast_mship && inp->inp_moptions != NULL) { 329 int mship, foundmship = 0; 330 331 for (mship = 0; mship < NMSHIPS(inp); mship++) { 332 if (MSHIP(inp, mship)->inm_addr.s_addr 333 == ip->ip_dst.s_addr && 334 MSHIP(inp, mship)->inm_ifp 335 == m->m_pkthdr.rcvif) { 336 foundmship = 1; 337 break; 338 } 339 } 340 if (foundmship == 0) { 341 INP_UNLOCK(inp); 342 continue; 343 } 344 } 345 #undef NMSHIPS 346 #undef MSHIP 347 if (last != NULL) { 348 struct mbuf *n; 349 350 n = m_copy(m, 0, M_COPYALL); 351 if (n != NULL) 352 udp_append(last, ip, n, 353 iphlen + 354 sizeof(struct udphdr), 355 &udp_in); 356 INP_UNLOCK(last); 357 } 358 last = inp; 359 /* 360 * Don't look for additional matches if this one does 361 * not have either the SO_REUSEPORT or SO_REUSEADDR 362 * socket options set. This heuristic avoids searching 363 * through all pcbs in the common case of a non-shared 364 * port. It * assumes that an application will never 365 * clear these options after setting them. 366 */ 367 if ((last->inp_socket->so_options&(SO_REUSEPORT|SO_REUSEADDR)) == 0) 368 break; 369 } 370 371 if (last == NULL) { 372 /* 373 * No matching pcb found; discard datagram. 374 * (No need to send an ICMP Port Unreachable 375 * for a broadcast or multicast datgram.) 376 */ 377 udpstat.udps_noportbcast++; 378 goto badheadlocked; 379 } 380 udp_append(last, ip, m, iphlen + sizeof(struct udphdr), 381 &udp_in); 382 INP_UNLOCK(last); 383 INP_INFO_RUNLOCK(&udbinfo); 384 return; 385 } 386 /* 387 * Locate pcb for datagram. 388 */ 389 inp = in_pcblookup_hash(&udbinfo, ip->ip_src, uh->uh_sport, 390 ip->ip_dst, uh->uh_dport, 1, m->m_pkthdr.rcvif); 391 if (inp == NULL) { 392 if (log_in_vain) { 393 char buf[4*sizeof "123"]; 394 395 strcpy(buf, inet_ntoa(ip->ip_dst)); 396 log(LOG_INFO, 397 "Connection attempt to UDP %s:%d from %s:%d\n", 398 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 399 ntohs(uh->uh_sport)); 400 } 401 udpstat.udps_noport++; 402 if (m->m_flags & (M_BCAST | M_MCAST)) { 403 udpstat.udps_noportbcast++; 404 goto badheadlocked; 405 } 406 if (blackhole) 407 goto badheadlocked; 408 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 409 goto badheadlocked; 410 *ip = save_ip; 411 ip->ip_len += iphlen; 412 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 413 INP_INFO_RUNLOCK(&udbinfo); 414 return; 415 } 416 INP_LOCK(inp); 417 /* Check the minimum TTL for socket. */ 418 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) 419 goto badheadlocked; 420 udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in); 421 INP_UNLOCK(inp); 422 INP_INFO_RUNLOCK(&udbinfo); 423 return; 424 425 badheadlocked: 426 if (inp) 427 INP_UNLOCK(inp); 428 INP_INFO_RUNLOCK(&udbinfo); 429 badunlocked: 430 m_freem(m); 431 return; 432 } 433 434 /* 435 * Subroutine of udp_input(), which appends the provided mbuf chain to the 436 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 437 * contains the source address. If the socket ends up being an IPv6 socket, 438 * udp_append() will convert to a sockaddr_in6 before passing the address 439 * into the socket code. 440 */ 441 static void 442 udp_append(inp, ip, n, off, udp_in) 443 struct inpcb *inp; 444 struct ip *ip; 445 struct mbuf *n; 446 int off; 447 struct sockaddr_in *udp_in; 448 { 449 struct sockaddr *append_sa; 450 struct socket *so; 451 struct mbuf *opts = 0; 452 #ifdef INET6 453 struct sockaddr_in6 udp_in6; 454 #endif 455 456 INP_LOCK_ASSERT(inp); 457 458 #if defined(IPSEC) || defined(FAST_IPSEC) 459 /* check AH/ESP integrity. */ 460 if (ipsec4_in_reject(n, inp)) { 461 #ifdef IPSEC 462 ipsecstat.in_polvio++; 463 #endif /*IPSEC*/ 464 m_freem(n); 465 return; 466 } 467 #endif /*IPSEC || FAST_IPSEC*/ 468 #ifdef MAC 469 if (mac_check_inpcb_deliver(inp, n) != 0) { 470 m_freem(n); 471 return; 472 } 473 #endif 474 if (inp->inp_flags & INP_CONTROLOPTS || 475 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 476 #ifdef INET6 477 if (inp->inp_vflag & INP_IPV6) { 478 int savedflags; 479 480 savedflags = inp->inp_flags; 481 inp->inp_flags &= ~INP_UNMAPPABLEOPTS; 482 ip6_savecontrol(inp, n, &opts); 483 inp->inp_flags = savedflags; 484 } else 485 #endif 486 ip_savecontrol(inp, &opts, ip, n); 487 } 488 #ifdef INET6 489 if (inp->inp_vflag & INP_IPV6) { 490 bzero(&udp_in6, sizeof(udp_in6)); 491 udp_in6.sin6_len = sizeof(udp_in6); 492 udp_in6.sin6_family = AF_INET6; 493 in6_sin_2_v4mapsin6(udp_in, &udp_in6); 494 append_sa = (struct sockaddr *)&udp_in6; 495 } else 496 #endif 497 append_sa = (struct sockaddr *)udp_in; 498 m_adj(n, off); 499 500 so = inp->inp_socket; 501 SOCKBUF_LOCK(&so->so_rcv); 502 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 503 m_freem(n); 504 if (opts) 505 m_freem(opts); 506 udpstat.udps_fullsock++; 507 SOCKBUF_UNLOCK(&so->so_rcv); 508 } else 509 sorwakeup_locked(so); 510 } 511 512 /* 513 * Notify a udp user of an asynchronous error; 514 * just wake up so that he can collect error status. 515 */ 516 struct inpcb * 517 udp_notify(inp, errno) 518 register struct inpcb *inp; 519 int errno; 520 { 521 inp->inp_socket->so_error = errno; 522 sorwakeup(inp->inp_socket); 523 sowwakeup(inp->inp_socket); 524 return inp; 525 } 526 527 void 528 udp_ctlinput(cmd, sa, vip) 529 int cmd; 530 struct sockaddr *sa; 531 void *vip; 532 { 533 struct ip *ip = vip; 534 struct udphdr *uh; 535 struct inpcb *(*notify)(struct inpcb *, int) = udp_notify; 536 struct in_addr faddr; 537 struct inpcb *inp; 538 539 faddr = ((struct sockaddr_in *)sa)->sin_addr; 540 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 541 return; 542 543 /* 544 * Redirects don't need to be handled up here. 545 */ 546 if (PRC_IS_REDIRECT(cmd)) 547 return; 548 /* 549 * Hostdead is ugly because it goes linearly through all PCBs. 550 * XXX: We never get this from ICMP, otherwise it makes an 551 * excellent DoS attack on machines with many connections. 552 */ 553 if (cmd == PRC_HOSTDEAD) 554 ip = 0; 555 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 556 return; 557 if (ip) { 558 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 559 INP_INFO_RLOCK(&udbinfo); 560 inp = in_pcblookup_hash(&udbinfo, faddr, uh->uh_dport, 561 ip->ip_src, uh->uh_sport, 0, NULL); 562 if (inp != NULL) { 563 INP_LOCK(inp); 564 if (inp->inp_socket != NULL) { 565 (*notify)(inp, inetctlerrmap[cmd]); 566 } 567 INP_UNLOCK(inp); 568 } 569 INP_INFO_RUNLOCK(&udbinfo); 570 } else 571 in_pcbnotifyall(&udbinfo, faddr, inetctlerrmap[cmd], notify); 572 } 573 574 static int 575 udp_pcblist(SYSCTL_HANDLER_ARGS) 576 { 577 int error, i, n; 578 struct inpcb *inp, **inp_list; 579 inp_gen_t gencnt; 580 struct xinpgen xig; 581 582 /* 583 * The process of preparing the TCB list is too time-consuming and 584 * resource-intensive to repeat twice on every request. 585 */ 586 if (req->oldptr == 0) { 587 n = udbinfo.ipi_count; 588 req->oldidx = 2 * (sizeof xig) 589 + (n + n/8) * sizeof(struct xinpcb); 590 return 0; 591 } 592 593 if (req->newptr != 0) 594 return EPERM; 595 596 /* 597 * OK, now we're committed to doing something. 598 */ 599 INP_INFO_RLOCK(&udbinfo); 600 gencnt = udbinfo.ipi_gencnt; 601 n = udbinfo.ipi_count; 602 INP_INFO_RUNLOCK(&udbinfo); 603 604 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 605 + n * sizeof(struct xinpcb)); 606 if (error != 0) 607 return (error); 608 609 xig.xig_len = sizeof xig; 610 xig.xig_count = n; 611 xig.xig_gen = gencnt; 612 xig.xig_sogen = so_gencnt; 613 error = SYSCTL_OUT(req, &xig, sizeof xig); 614 if (error) 615 return error; 616 617 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 618 if (inp_list == 0) 619 return ENOMEM; 620 621 INP_INFO_RLOCK(&udbinfo); 622 for (inp = LIST_FIRST(udbinfo.listhead), i = 0; inp && i < n; 623 inp = LIST_NEXT(inp, inp_list)) { 624 INP_LOCK(inp); 625 if (inp->inp_gencnt <= gencnt && 626 cr_canseesocket(req->td->td_ucred, inp->inp_socket) == 0) 627 inp_list[i++] = inp; 628 INP_UNLOCK(inp); 629 } 630 INP_INFO_RUNLOCK(&udbinfo); 631 n = i; 632 633 error = 0; 634 for (i = 0; i < n; i++) { 635 inp = inp_list[i]; 636 if (inp->inp_gencnt <= gencnt) { 637 struct xinpcb xi; 638 bzero(&xi, sizeof(xi)); 639 xi.xi_len = sizeof xi; 640 /* XXX should avoid extra copy */ 641 bcopy(inp, &xi.xi_inp, sizeof *inp); 642 if (inp->inp_socket) 643 sotoxsocket(inp->inp_socket, &xi.xi_socket); 644 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 645 error = SYSCTL_OUT(req, &xi, sizeof xi); 646 } 647 } 648 if (!error) { 649 /* 650 * Give the user an updated idea of our state. 651 * If the generation differs from what we told 652 * her before, she knows that something happened 653 * while we were processing this request, and it 654 * might be necessary to retry. 655 */ 656 INP_INFO_RLOCK(&udbinfo); 657 xig.xig_gen = udbinfo.ipi_gencnt; 658 xig.xig_sogen = so_gencnt; 659 xig.xig_count = udbinfo.ipi_count; 660 INP_INFO_RUNLOCK(&udbinfo); 661 error = SYSCTL_OUT(req, &xig, sizeof xig); 662 } 663 free(inp_list, M_TEMP); 664 return error; 665 } 666 667 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 668 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 669 670 static int 671 udp_getcred(SYSCTL_HANDLER_ARGS) 672 { 673 struct xucred xuc; 674 struct sockaddr_in addrs[2]; 675 struct inpcb *inp; 676 int error; 677 678 error = suser_cred(req->td->td_ucred, SUSER_ALLOWJAIL); 679 if (error) 680 return (error); 681 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 682 if (error) 683 return (error); 684 INP_INFO_RLOCK(&udbinfo); 685 inp = in_pcblookup_hash(&udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 686 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL); 687 if (inp == NULL || inp->inp_socket == NULL) { 688 error = ENOENT; 689 goto out; 690 } 691 error = cr_canseesocket(req->td->td_ucred, inp->inp_socket); 692 if (error) 693 goto out; 694 cru2x(inp->inp_socket->so_cred, &xuc); 695 out: 696 INP_INFO_RUNLOCK(&udbinfo); 697 if (error == 0) 698 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 699 return (error); 700 } 701 702 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 703 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 704 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 705 706 static int 707 udp_output(inp, m, addr, control, td) 708 register struct inpcb *inp; 709 struct mbuf *m; 710 struct sockaddr *addr; 711 struct mbuf *control; 712 struct thread *td; 713 { 714 register struct udpiphdr *ui; 715 register int len = m->m_pkthdr.len; 716 struct in_addr faddr, laddr; 717 struct cmsghdr *cm; 718 struct sockaddr_in *sin, src; 719 int error = 0; 720 int ipflags; 721 u_short fport, lport; 722 int unlock_udbinfo; 723 724 /* 725 * udp_output() may need to temporarily bind or connect the current 726 * inpcb. As such, we don't know up front what inpcb locks we will 727 * need. Do any work to decide what is needed up front before 728 * acquiring locks. 729 */ 730 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 731 if (control) 732 m_freem(control); 733 m_freem(m); 734 return EMSGSIZE; 735 } 736 737 src.sin_addr.s_addr = INADDR_ANY; 738 if (control != NULL) { 739 /* 740 * XXX: Currently, we assume all the optional information 741 * is stored in a single mbuf. 742 */ 743 if (control->m_next) { 744 m_freem(control); 745 m_freem(m); 746 return EINVAL; 747 } 748 for (; control->m_len > 0; 749 control->m_data += CMSG_ALIGN(cm->cmsg_len), 750 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 751 cm = mtod(control, struct cmsghdr *); 752 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 || 753 cm->cmsg_len > control->m_len) { 754 error = EINVAL; 755 break; 756 } 757 if (cm->cmsg_level != IPPROTO_IP) 758 continue; 759 760 switch (cm->cmsg_type) { 761 case IP_SENDSRCADDR: 762 if (cm->cmsg_len != 763 CMSG_LEN(sizeof(struct in_addr))) { 764 error = EINVAL; 765 break; 766 } 767 bzero(&src, sizeof(src)); 768 src.sin_family = AF_INET; 769 src.sin_len = sizeof(src); 770 src.sin_port = inp->inp_lport; 771 src.sin_addr = *(struct in_addr *)CMSG_DATA(cm); 772 break; 773 default: 774 error = ENOPROTOOPT; 775 break; 776 } 777 if (error) 778 break; 779 } 780 m_freem(control); 781 } 782 if (error) { 783 m_freem(m); 784 return error; 785 } 786 787 if (src.sin_addr.s_addr != INADDR_ANY || 788 addr != NULL) { 789 INP_INFO_WLOCK(&udbinfo); 790 unlock_udbinfo = 1; 791 } else 792 unlock_udbinfo = 0; 793 INP_LOCK(inp); 794 795 #ifdef MAC 796 mac_create_mbuf_from_inpcb(inp, m); 797 #endif 798 799 laddr = inp->inp_laddr; 800 lport = inp->inp_lport; 801 if (src.sin_addr.s_addr != INADDR_ANY) { 802 if (lport == 0) { 803 error = EINVAL; 804 goto release; 805 } 806 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 807 &laddr.s_addr, &lport, td->td_ucred); 808 if (error) 809 goto release; 810 } 811 812 if (addr) { 813 sin = (struct sockaddr_in *)addr; 814 if (jailed(td->td_ucred)) 815 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr); 816 if (inp->inp_faddr.s_addr != INADDR_ANY) { 817 error = EISCONN; 818 goto release; 819 } 820 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, &lport, 821 &faddr.s_addr, &fport, NULL, td->td_ucred); 822 if (error) 823 goto release; 824 825 /* Commit the local port if newly assigned. */ 826 if (inp->inp_laddr.s_addr == INADDR_ANY && 827 inp->inp_lport == 0) { 828 /* 829 * Remember addr if jailed, to prevent rebinding. 830 */ 831 if (jailed(td->td_ucred)) 832 inp->inp_laddr = laddr; 833 inp->inp_lport = lport; 834 if (in_pcbinshash(inp) != 0) { 835 inp->inp_lport = 0; 836 error = EAGAIN; 837 goto release; 838 } 839 inp->inp_flags |= INP_ANONPORT; 840 } 841 } else { 842 faddr = inp->inp_faddr; 843 fport = inp->inp_fport; 844 if (faddr.s_addr == INADDR_ANY) { 845 error = ENOTCONN; 846 goto release; 847 } 848 } 849 850 /* 851 * Calculate data length and get a mbuf for UDP, IP, and possible 852 * link-layer headers. Immediate slide the data pointer back forward 853 * since we won't use that space at this layer. 854 */ 855 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT); 856 if (m == NULL) { 857 error = ENOBUFS; 858 goto release; 859 } 860 m->m_data += max_linkhdr; 861 m->m_len -= max_linkhdr; 862 m->m_pkthdr.len -= max_linkhdr; 863 864 /* 865 * Fill in mbuf with extended UDP header 866 * and addresses and length put into network format. 867 */ 868 ui = mtod(m, struct udpiphdr *); 869 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 870 ui->ui_pr = IPPROTO_UDP; 871 ui->ui_src = laddr; 872 ui->ui_dst = faddr; 873 ui->ui_sport = lport; 874 ui->ui_dport = fport; 875 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 876 877 /* 878 * Set the Don't Fragment bit in the IP header. 879 */ 880 if (inp->inp_flags & INP_DONTFRAG) { 881 struct ip *ip; 882 ip = (struct ip *)&ui->ui_i; 883 ip->ip_off |= IP_DF; 884 } 885 886 ipflags = 0; 887 if (inp->inp_socket->so_options & SO_DONTROUTE) 888 ipflags |= IP_ROUTETOIF; 889 if (inp->inp_socket->so_options & SO_BROADCAST) 890 ipflags |= IP_ALLOWBROADCAST; 891 if (inp->inp_vflag & INP_ONESBCAST) 892 ipflags |= IP_SENDONES; 893 894 /* 895 * Set up checksum and output datagram. 896 */ 897 if (udpcksum) { 898 if (inp->inp_vflag & INP_ONESBCAST) 899 faddr.s_addr = INADDR_BROADCAST; 900 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 901 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 902 m->m_pkthdr.csum_flags = CSUM_UDP; 903 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 904 } else { 905 ui->ui_sum = 0; 906 } 907 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 908 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 909 ((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */ 910 udpstat.udps_opackets++; 911 912 if (unlock_udbinfo) 913 INP_INFO_WUNLOCK(&udbinfo); 914 error = ip_output(m, inp->inp_options, NULL, ipflags, 915 inp->inp_moptions, inp); 916 INP_UNLOCK(inp); 917 return (error); 918 919 release: 920 INP_UNLOCK(inp); 921 if (unlock_udbinfo) 922 INP_INFO_WUNLOCK(&udbinfo); 923 m_freem(m); 924 return (error); 925 } 926 927 u_long udp_sendspace = 9216; /* really max datagram size */ 928 /* 40 1K datagrams */ 929 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 930 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 931 932 u_long udp_recvspace = 40 * (1024 + 933 #ifdef INET6 934 sizeof(struct sockaddr_in6) 935 #else 936 sizeof(struct sockaddr_in) 937 #endif 938 ); 939 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 940 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 941 942 static void 943 udp_abort(struct socket *so) 944 { 945 struct inpcb *inp; 946 947 inp = sotoinpcb(so); 948 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 949 INP_INFO_WLOCK(&udbinfo); 950 INP_LOCK(inp); 951 soisdisconnected(so); 952 in_pcbdetach(inp); 953 in_pcbfree(inp); 954 INP_INFO_WUNLOCK(&udbinfo); 955 } 956 957 static int 958 udp_attach(struct socket *so, int proto, struct thread *td) 959 { 960 struct inpcb *inp; 961 int error; 962 963 inp = sotoinpcb(so); 964 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 965 error = soreserve(so, udp_sendspace, udp_recvspace); 966 if (error) 967 return error; 968 INP_INFO_WLOCK(&udbinfo); 969 error = in_pcballoc(so, &udbinfo, "udpinp"); 970 if (error) { 971 INP_INFO_WUNLOCK(&udbinfo); 972 return error; 973 } 974 975 inp = (struct inpcb *)so->so_pcb; 976 INP_LOCK(inp); 977 INP_INFO_WUNLOCK(&udbinfo); 978 inp->inp_vflag |= INP_IPV4; 979 inp->inp_ip_ttl = ip_defttl; 980 INP_UNLOCK(inp); 981 return 0; 982 } 983 984 static int 985 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 986 { 987 struct inpcb *inp; 988 int error; 989 990 inp = sotoinpcb(so); 991 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 992 INP_INFO_WLOCK(&udbinfo); 993 INP_LOCK(inp); 994 error = in_pcbbind(inp, nam, td->td_ucred); 995 INP_UNLOCK(inp); 996 INP_INFO_WUNLOCK(&udbinfo); 997 return error; 998 } 999 1000 static int 1001 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1002 { 1003 struct inpcb *inp; 1004 int error; 1005 struct sockaddr_in *sin; 1006 1007 inp = sotoinpcb(so); 1008 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1009 INP_INFO_WLOCK(&udbinfo); 1010 INP_LOCK(inp); 1011 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1012 INP_UNLOCK(inp); 1013 INP_INFO_WUNLOCK(&udbinfo); 1014 return EISCONN; 1015 } 1016 sin = (struct sockaddr_in *)nam; 1017 if (jailed(td->td_ucred)) 1018 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr); 1019 error = in_pcbconnect(inp, nam, td->td_ucred); 1020 if (error == 0) 1021 soisconnected(so); 1022 INP_UNLOCK(inp); 1023 INP_INFO_WUNLOCK(&udbinfo); 1024 return error; 1025 } 1026 1027 static void 1028 udp_detach(struct socket *so) 1029 { 1030 struct inpcb *inp; 1031 1032 inp = sotoinpcb(so); 1033 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1034 INP_INFO_WLOCK(&udbinfo); 1035 INP_LOCK(inp); 1036 in_pcbdetach(inp); 1037 in_pcbfree(inp); 1038 INP_INFO_WUNLOCK(&udbinfo); 1039 } 1040 1041 static int 1042 udp_disconnect(struct socket *so) 1043 { 1044 struct inpcb *inp; 1045 1046 inp = sotoinpcb(so); 1047 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1048 INP_INFO_WLOCK(&udbinfo); 1049 INP_LOCK(inp); 1050 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1051 INP_INFO_WUNLOCK(&udbinfo); 1052 INP_UNLOCK(inp); 1053 return ENOTCONN; 1054 } 1055 1056 in_pcbdisconnect(inp); 1057 inp->inp_laddr.s_addr = INADDR_ANY; 1058 SOCK_LOCK(so); 1059 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1060 SOCK_UNLOCK(so); 1061 INP_UNLOCK(inp); 1062 INP_INFO_WUNLOCK(&udbinfo); 1063 return 0; 1064 } 1065 1066 static int 1067 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1068 struct mbuf *control, struct thread *td) 1069 { 1070 struct inpcb *inp; 1071 1072 inp = sotoinpcb(so); 1073 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1074 return udp_output(inp, m, addr, control, td); 1075 } 1076 1077 int 1078 udp_shutdown(struct socket *so) 1079 { 1080 struct inpcb *inp; 1081 1082 inp = sotoinpcb(so); 1083 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1084 INP_LOCK(inp); 1085 socantsendmore(so); 1086 INP_UNLOCK(inp); 1087 return 0; 1088 } 1089 1090 /* 1091 * This is the wrapper function for in_setsockaddr. We just pass down 1092 * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking 1093 * here because in_setsockaddr will call malloc and might block. 1094 */ 1095 static int 1096 udp_sockaddr(struct socket *so, struct sockaddr **nam) 1097 { 1098 return (in_setsockaddr(so, nam, &udbinfo)); 1099 } 1100 1101 /* 1102 * This is the wrapper function for in_setpeeraddr. We just pass down 1103 * the pcbinfo for in_setpeeraddr to lock. 1104 */ 1105 static int 1106 udp_peeraddr(struct socket *so, struct sockaddr **nam) 1107 { 1108 return (in_setpeeraddr(so, nam, &udbinfo)); 1109 } 1110 1111 struct pr_usrreqs udp_usrreqs = { 1112 .pru_abort = udp_abort, 1113 .pru_attach = udp_attach, 1114 .pru_bind = udp_bind, 1115 .pru_connect = udp_connect, 1116 .pru_control = in_control, 1117 .pru_detach = udp_detach, 1118 .pru_disconnect = udp_disconnect, 1119 .pru_peeraddr = udp_peeraddr, 1120 .pru_send = udp_send, 1121 .pru_sosend = sosend_dgram, 1122 .pru_shutdown = udp_shutdown, 1123 .pru_sockaddr = udp_sockaddr, 1124 .pru_sosetlabel = in_pcbsosetlabel 1125 }; 1126