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