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/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/priv.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 #include <security/mac/mac_framework.h> 91 92 /* 93 * UDP protocol implementation. 94 * Per RFC 768, August, 1980. 95 */ 96 #ifndef COMPAT_42 97 static int udpcksum = 1; 98 #else 99 static int udpcksum = 0; /* XXX */ 100 #endif 101 SYSCTL_INT(_net_inet_udp, UDPCTL_CHECKSUM, checksum, CTLFLAG_RW, 102 &udpcksum, 0, ""); 103 104 int log_in_vain = 0; 105 SYSCTL_INT(_net_inet_udp, OID_AUTO, log_in_vain, CTLFLAG_RW, 106 &log_in_vain, 0, "Log all incoming UDP packets"); 107 108 static int blackhole = 0; 109 SYSCTL_INT(_net_inet_udp, OID_AUTO, blackhole, CTLFLAG_RW, 110 &blackhole, 0, "Do not send port unreachables for refused connects"); 111 112 static int strict_mcast_mship = 0; 113 SYSCTL_INT(_net_inet_udp, OID_AUTO, strict_mcast_mship, CTLFLAG_RW, 114 &strict_mcast_mship, 0, "Only send multicast to member sockets"); 115 116 struct inpcbhead udb; /* from udp_var.h */ 117 #define udb6 udb /* for KAME src sync over BSD*'s */ 118 struct inpcbinfo udbinfo; 119 120 #ifndef UDBHASHSIZE 121 #define UDBHASHSIZE 16 122 #endif 123 124 struct udpstat udpstat; /* from udp_var.h */ 125 SYSCTL_STRUCT(_net_inet_udp, UDPCTL_STATS, stats, CTLFLAG_RW, 126 &udpstat, udpstat, "UDP statistics (struct udpstat, netinet/udp_var.h)"); 127 128 static void udp_append(struct inpcb *last, struct ip *ip, struct mbuf *n, 129 int off, struct sockaddr_in *udp_in); 130 131 static void udp_detach(struct socket *so); 132 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 133 struct mbuf *, struct thread *); 134 135 static void 136 udp_zone_change(void *tag) 137 { 138 139 uma_zone_set_max(udbinfo.ipi_zone, maxsockets); 140 } 141 142 static int 143 udp_inpcb_init(void *mem, int size, int flags) 144 { 145 struct inpcb *inp = (struct inpcb *) mem; 146 INP_LOCK_INIT(inp, "inp", "udpinp"); 147 return (0); 148 } 149 150 void 151 udp_init() 152 { 153 INP_INFO_LOCK_INIT(&udbinfo, "udp"); 154 LIST_INIT(&udb); 155 udbinfo.listhead = &udb; 156 udbinfo.hashbase = hashinit(UDBHASHSIZE, M_PCB, &udbinfo.hashmask); 157 udbinfo.porthashbase = hashinit(UDBHASHSIZE, M_PCB, 158 &udbinfo.porthashmask); 159 udbinfo.ipi_zone = uma_zcreate("udpcb", sizeof(struct inpcb), NULL, 160 NULL, udp_inpcb_init, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 161 uma_zone_set_max(udbinfo.ipi_zone, maxsockets); 162 EVENTHANDLER_REGISTER(maxsockets_change, udp_zone_change, NULL, 163 EVENTHANDLER_PRI_ANY); 164 } 165 166 void 167 udp_input(m, off) 168 register struct mbuf *m; 169 int off; 170 { 171 int iphlen = off; 172 register struct ip *ip; 173 register struct udphdr *uh; 174 register struct inpcb *inp; 175 int len; 176 struct ip save_ip; 177 struct sockaddr_in udp_in; 178 #ifdef IPFIREWALL_FORWARD 179 struct m_tag *fwd_tag; 180 #endif 181 182 udpstat.udps_ipackets++; 183 184 /* 185 * Strip IP options, if any; should skip this, 186 * make available to user, and use on returned packets, 187 * but we don't yet have a way to check the checksum 188 * with options still present. 189 */ 190 if (iphlen > sizeof (struct ip)) { 191 ip_stripoptions(m, (struct mbuf *)0); 192 iphlen = sizeof(struct ip); 193 } 194 195 /* 196 * Get IP and UDP header together in first mbuf. 197 */ 198 ip = mtod(m, struct ip *); 199 if (m->m_len < iphlen + sizeof(struct udphdr)) { 200 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 201 udpstat.udps_hdrops++; 202 return; 203 } 204 ip = mtod(m, struct ip *); 205 } 206 uh = (struct udphdr *)((caddr_t)ip + iphlen); 207 208 /* destination port of 0 is illegal, based on RFC768. */ 209 if (uh->uh_dport == 0) 210 goto badunlocked; 211 212 /* 213 * Construct sockaddr format source address. 214 * Stuff source address and datagram in user buffer. 215 */ 216 bzero(&udp_in, sizeof(udp_in)); 217 udp_in.sin_len = sizeof(udp_in); 218 udp_in.sin_family = AF_INET; 219 udp_in.sin_port = uh->uh_sport; 220 udp_in.sin_addr = ip->ip_src; 221 222 /* 223 * Make mbuf data length reflect UDP length. 224 * If not enough data to reflect UDP length, drop. 225 */ 226 len = ntohs((u_short)uh->uh_ulen); 227 if (ip->ip_len != len) { 228 if (len > ip->ip_len || len < sizeof(struct udphdr)) { 229 udpstat.udps_badlen++; 230 goto badunlocked; 231 } 232 m_adj(m, len - ip->ip_len); 233 /* ip->ip_len = len; */ 234 } 235 /* 236 * Save a copy of the IP header in case we want restore it 237 * for sending an ICMP error message in response. 238 */ 239 if (!blackhole) 240 save_ip = *ip; 241 242 /* 243 * Checksum extended UDP header and data. 244 */ 245 if (uh->uh_sum) { 246 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 247 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 248 uh->uh_sum = m->m_pkthdr.csum_data; 249 else 250 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, 251 ip->ip_dst.s_addr, htonl((u_short)len + 252 m->m_pkthdr.csum_data + IPPROTO_UDP)); 253 uh->uh_sum ^= 0xffff; 254 } else { 255 char b[9]; 256 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 257 bzero(((struct ipovly *)ip)->ih_x1, 9); 258 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 259 uh->uh_sum = in_cksum(m, len + sizeof (struct ip)); 260 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 261 } 262 if (uh->uh_sum) { 263 udpstat.udps_badsum++; 264 m_freem(m); 265 return; 266 } 267 } else 268 udpstat.udps_nosum++; 269 270 #ifdef IPFIREWALL_FORWARD 271 /* Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. */ 272 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 273 274 if (fwd_tag != NULL) { 275 struct sockaddr_in *next_hop; 276 277 /* Do the hack. */ 278 next_hop = (struct sockaddr_in *)(fwd_tag + 1); 279 ip->ip_dst = next_hop->sin_addr; 280 uh->uh_dport = ntohs(next_hop->sin_port); 281 /* Remove the tag from the packet. We don't need it anymore. */ 282 m_tag_delete(m, fwd_tag); 283 } 284 #endif 285 286 INP_INFO_RLOCK(&udbinfo); 287 288 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 289 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 290 struct inpcb *last; 291 /* 292 * Deliver a multicast or broadcast datagram to *all* sockets 293 * for which the local and remote addresses and ports match 294 * those of the incoming datagram. This allows more than 295 * one process to receive multi/broadcasts on the same port. 296 * (This really ought to be done for unicast datagrams as 297 * well, but that would cause problems with existing 298 * applications that open both address-specific sockets and 299 * a wildcard socket listening to the same port -- they would 300 * end up receiving duplicates of every unicast datagram. 301 * Those applications open the multiple sockets to overcome an 302 * inadequacy of the UDP socket interface, but for backwards 303 * compatibility we avoid the problem here rather than 304 * fixing the interface. Maybe 4.5BSD will remedy this?) 305 */ 306 307 /* 308 * Locate pcb(s) for datagram. 309 * (Algorithm copied from raw_intr().) 310 */ 311 last = NULL; 312 LIST_FOREACH(inp, &udb, inp_list) { 313 if (inp->inp_lport != uh->uh_dport) 314 continue; 315 #ifdef INET6 316 if ((inp->inp_vflag & INP_IPV4) == 0) 317 continue; 318 #endif 319 if (inp->inp_laddr.s_addr != INADDR_ANY) { 320 if (inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 321 continue; 322 } 323 if (inp->inp_faddr.s_addr != INADDR_ANY) { 324 if (inp->inp_faddr.s_addr != 325 ip->ip_src.s_addr || 326 inp->inp_fport != uh->uh_sport) 327 continue; 328 } 329 INP_LOCK(inp); 330 331 /* 332 * Check multicast packets to make sure they are only 333 * sent to sockets with multicast memberships for the 334 * packet's destination address and arrival interface 335 */ 336 #define MSHIP(_inp, n) ((_inp)->inp_moptions->imo_membership[(n)]) 337 #define NMSHIPS(_inp) ((_inp)->inp_moptions->imo_num_memberships) 338 if (strict_mcast_mship && inp->inp_moptions != NULL) { 339 int mship, foundmship = 0; 340 341 for (mship = 0; mship < NMSHIPS(inp); mship++) { 342 if (MSHIP(inp, mship)->inm_addr.s_addr 343 == ip->ip_dst.s_addr && 344 MSHIP(inp, mship)->inm_ifp 345 == m->m_pkthdr.rcvif) { 346 foundmship = 1; 347 break; 348 } 349 } 350 if (foundmship == 0) { 351 INP_UNLOCK(inp); 352 continue; 353 } 354 } 355 #undef NMSHIPS 356 #undef MSHIP 357 if (last != NULL) { 358 struct mbuf *n; 359 360 n = m_copy(m, 0, M_COPYALL); 361 if (n != NULL) 362 udp_append(last, ip, n, 363 iphlen + 364 sizeof(struct udphdr), 365 &udp_in); 366 INP_UNLOCK(last); 367 } 368 last = inp; 369 /* 370 * Don't look for additional matches if this one does 371 * not have either the SO_REUSEPORT or SO_REUSEADDR 372 * socket options set. This heuristic avoids searching 373 * through all pcbs in the common case of a non-shared 374 * port. It assumes that an application will never 375 * clear these options after setting them. 376 */ 377 if ((last->inp_socket->so_options&(SO_REUSEPORT|SO_REUSEADDR)) == 0) 378 break; 379 } 380 381 if (last == NULL) { 382 /* 383 * No matching pcb found; discard datagram. 384 * (No need to send an ICMP Port Unreachable 385 * for a broadcast or multicast datgram.) 386 */ 387 udpstat.udps_noportbcast++; 388 goto badheadlocked; 389 } 390 udp_append(last, ip, m, iphlen + sizeof(struct udphdr), 391 &udp_in); 392 INP_UNLOCK(last); 393 INP_INFO_RUNLOCK(&udbinfo); 394 return; 395 } 396 /* 397 * Locate pcb for datagram. 398 */ 399 inp = in_pcblookup_hash(&udbinfo, ip->ip_src, uh->uh_sport, 400 ip->ip_dst, uh->uh_dport, 1, m->m_pkthdr.rcvif); 401 if (inp == NULL) { 402 if (log_in_vain) { 403 char buf[4*sizeof "123"]; 404 405 strcpy(buf, inet_ntoa(ip->ip_dst)); 406 log(LOG_INFO, 407 "Connection attempt to UDP %s:%d from %s:%d\n", 408 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 409 ntohs(uh->uh_sport)); 410 } 411 udpstat.udps_noport++; 412 if (m->m_flags & (M_BCAST | M_MCAST)) { 413 udpstat.udps_noportbcast++; 414 goto badheadlocked; 415 } 416 if (blackhole) 417 goto badheadlocked; 418 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 419 goto badheadlocked; 420 *ip = save_ip; 421 ip->ip_len += iphlen; 422 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 423 INP_INFO_RUNLOCK(&udbinfo); 424 return; 425 } 426 INP_LOCK(inp); 427 /* Check the minimum TTL for socket. */ 428 if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) 429 goto badheadlocked; 430 udp_append(inp, ip, m, iphlen + sizeof(struct udphdr), &udp_in); 431 INP_UNLOCK(inp); 432 INP_INFO_RUNLOCK(&udbinfo); 433 return; 434 435 badheadlocked: 436 if (inp) 437 INP_UNLOCK(inp); 438 INP_INFO_RUNLOCK(&udbinfo); 439 badunlocked: 440 m_freem(m); 441 return; 442 } 443 444 /* 445 * Subroutine of udp_input(), which appends the provided mbuf chain to the 446 * passed pcb/socket. The caller must provide a sockaddr_in via udp_in that 447 * contains the source address. If the socket ends up being an IPv6 socket, 448 * udp_append() will convert to a sockaddr_in6 before passing the address 449 * into the socket code. 450 */ 451 static void 452 udp_append(inp, ip, n, off, udp_in) 453 struct inpcb *inp; 454 struct ip *ip; 455 struct mbuf *n; 456 int off; 457 struct sockaddr_in *udp_in; 458 { 459 struct sockaddr *append_sa; 460 struct socket *so; 461 struct mbuf *opts = 0; 462 #ifdef INET6 463 struct sockaddr_in6 udp_in6; 464 #endif 465 466 INP_LOCK_ASSERT(inp); 467 468 #if defined(IPSEC) || defined(FAST_IPSEC) 469 /* check AH/ESP integrity. */ 470 if (ipsec4_in_reject(n, inp)) { 471 #ifdef IPSEC 472 ipsecstat.in_polvio++; 473 #endif /*IPSEC*/ 474 m_freem(n); 475 return; 476 } 477 #endif /*IPSEC || FAST_IPSEC*/ 478 #ifdef MAC 479 if (mac_check_inpcb_deliver(inp, n) != 0) { 480 m_freem(n); 481 return; 482 } 483 #endif 484 if (inp->inp_flags & INP_CONTROLOPTS || 485 inp->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 486 #ifdef INET6 487 if (inp->inp_vflag & INP_IPV6) { 488 int savedflags; 489 490 savedflags = inp->inp_flags; 491 inp->inp_flags &= ~INP_UNMAPPABLEOPTS; 492 ip6_savecontrol(inp, n, &opts); 493 inp->inp_flags = savedflags; 494 } else 495 #endif 496 ip_savecontrol(inp, &opts, ip, n); 497 } 498 #ifdef INET6 499 if (inp->inp_vflag & INP_IPV6) { 500 bzero(&udp_in6, sizeof(udp_in6)); 501 udp_in6.sin6_len = sizeof(udp_in6); 502 udp_in6.sin6_family = AF_INET6; 503 in6_sin_2_v4mapsin6(udp_in, &udp_in6); 504 append_sa = (struct sockaddr *)&udp_in6; 505 } else 506 #endif 507 append_sa = (struct sockaddr *)udp_in; 508 m_adj(n, off); 509 510 so = inp->inp_socket; 511 SOCKBUF_LOCK(&so->so_rcv); 512 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 513 m_freem(n); 514 if (opts) 515 m_freem(opts); 516 udpstat.udps_fullsock++; 517 SOCKBUF_UNLOCK(&so->so_rcv); 518 } else 519 sorwakeup_locked(so); 520 } 521 522 /* 523 * Notify a udp user of an asynchronous error; 524 * just wake up so that he can collect error status. 525 */ 526 struct inpcb * 527 udp_notify(inp, errno) 528 register struct inpcb *inp; 529 int errno; 530 { 531 inp->inp_socket->so_error = errno; 532 sorwakeup(inp->inp_socket); 533 sowwakeup(inp->inp_socket); 534 return inp; 535 } 536 537 void 538 udp_ctlinput(cmd, sa, vip) 539 int cmd; 540 struct sockaddr *sa; 541 void *vip; 542 { 543 struct ip *ip = vip; 544 struct udphdr *uh; 545 struct inpcb *(*notify)(struct inpcb *, int) = udp_notify; 546 struct in_addr faddr; 547 struct inpcb *inp; 548 549 faddr = ((struct sockaddr_in *)sa)->sin_addr; 550 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 551 return; 552 553 /* 554 * Redirects don't need to be handled up here. 555 */ 556 if (PRC_IS_REDIRECT(cmd)) 557 return; 558 /* 559 * Hostdead is ugly because it goes linearly through all PCBs. 560 * XXX: We never get this from ICMP, otherwise it makes an 561 * excellent DoS attack on machines with many connections. 562 */ 563 if (cmd == PRC_HOSTDEAD) 564 ip = 0; 565 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 566 return; 567 if (ip) { 568 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 569 INP_INFO_RLOCK(&udbinfo); 570 inp = in_pcblookup_hash(&udbinfo, faddr, uh->uh_dport, 571 ip->ip_src, uh->uh_sport, 0, NULL); 572 if (inp != NULL) { 573 INP_LOCK(inp); 574 if (inp->inp_socket != NULL) { 575 (*notify)(inp, inetctlerrmap[cmd]); 576 } 577 INP_UNLOCK(inp); 578 } 579 INP_INFO_RUNLOCK(&udbinfo); 580 } else 581 in_pcbnotifyall(&udbinfo, faddr, inetctlerrmap[cmd], notify); 582 } 583 584 static int 585 udp_pcblist(SYSCTL_HANDLER_ARGS) 586 { 587 int error, i, n; 588 struct inpcb *inp, **inp_list; 589 inp_gen_t gencnt; 590 struct xinpgen xig; 591 592 /* 593 * The process of preparing the TCB list is too time-consuming and 594 * resource-intensive to repeat twice on every request. 595 */ 596 if (req->oldptr == 0) { 597 n = udbinfo.ipi_count; 598 req->oldidx = 2 * (sizeof xig) 599 + (n + n/8) * sizeof(struct xinpcb); 600 return 0; 601 } 602 603 if (req->newptr != 0) 604 return EPERM; 605 606 /* 607 * OK, now we're committed to doing something. 608 */ 609 INP_INFO_RLOCK(&udbinfo); 610 gencnt = udbinfo.ipi_gencnt; 611 n = udbinfo.ipi_count; 612 INP_INFO_RUNLOCK(&udbinfo); 613 614 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 615 + n * sizeof(struct xinpcb)); 616 if (error != 0) 617 return (error); 618 619 xig.xig_len = sizeof xig; 620 xig.xig_count = n; 621 xig.xig_gen = gencnt; 622 xig.xig_sogen = so_gencnt; 623 error = SYSCTL_OUT(req, &xig, sizeof xig); 624 if (error) 625 return error; 626 627 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 628 if (inp_list == 0) 629 return ENOMEM; 630 631 INP_INFO_RLOCK(&udbinfo); 632 for (inp = LIST_FIRST(udbinfo.listhead), i = 0; inp && i < n; 633 inp = LIST_NEXT(inp, inp_list)) { 634 INP_LOCK(inp); 635 if (inp->inp_gencnt <= gencnt && 636 cr_canseesocket(req->td->td_ucred, inp->inp_socket) == 0) 637 inp_list[i++] = inp; 638 INP_UNLOCK(inp); 639 } 640 INP_INFO_RUNLOCK(&udbinfo); 641 n = i; 642 643 error = 0; 644 for (i = 0; i < n; i++) { 645 inp = inp_list[i]; 646 INP_LOCK(inp); 647 if (inp->inp_gencnt <= gencnt) { 648 struct xinpcb xi; 649 bzero(&xi, sizeof(xi)); 650 xi.xi_len = sizeof xi; 651 /* XXX should avoid extra copy */ 652 bcopy(inp, &xi.xi_inp, sizeof *inp); 653 if (inp->inp_socket) 654 sotoxsocket(inp->inp_socket, &xi.xi_socket); 655 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 656 INP_UNLOCK(inp); 657 error = SYSCTL_OUT(req, &xi, sizeof xi); 658 } else 659 INP_UNLOCK(inp); 660 } 661 if (!error) { 662 /* 663 * Give the user an updated idea of our state. 664 * If the generation differs from what we told 665 * her before, she knows that something happened 666 * while we were processing this request, and it 667 * might be necessary to retry. 668 */ 669 INP_INFO_RLOCK(&udbinfo); 670 xig.xig_gen = udbinfo.ipi_gencnt; 671 xig.xig_sogen = so_gencnt; 672 xig.xig_count = udbinfo.ipi_count; 673 INP_INFO_RUNLOCK(&udbinfo); 674 error = SYSCTL_OUT(req, &xig, sizeof xig); 675 } 676 free(inp_list, M_TEMP); 677 return error; 678 } 679 680 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 681 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 682 683 static int 684 udp_getcred(SYSCTL_HANDLER_ARGS) 685 { 686 struct xucred xuc; 687 struct sockaddr_in addrs[2]; 688 struct inpcb *inp; 689 int error; 690 691 error = priv_check_cred(req->td->td_ucred, PRIV_NETINET_GETCRED, 692 SUSER_ALLOWJAIL); 693 if (error) 694 return (error); 695 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 696 if (error) 697 return (error); 698 INP_INFO_RLOCK(&udbinfo); 699 inp = in_pcblookup_hash(&udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 700 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL); 701 if (inp == NULL || inp->inp_socket == NULL) { 702 error = ENOENT; 703 goto out; 704 } 705 error = cr_canseesocket(req->td->td_ucred, inp->inp_socket); 706 if (error) 707 goto out; 708 cru2x(inp->inp_socket->so_cred, &xuc); 709 out: 710 INP_INFO_RUNLOCK(&udbinfo); 711 if (error == 0) 712 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 713 return (error); 714 } 715 716 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 717 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 718 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 719 720 static int 721 udp_output(inp, m, addr, control, td) 722 register struct inpcb *inp; 723 struct mbuf *m; 724 struct sockaddr *addr; 725 struct mbuf *control; 726 struct thread *td; 727 { 728 register struct udpiphdr *ui; 729 register int len = m->m_pkthdr.len; 730 struct in_addr faddr, laddr; 731 struct cmsghdr *cm; 732 struct sockaddr_in *sin, src; 733 int error = 0; 734 int ipflags; 735 u_short fport, lport; 736 int unlock_udbinfo; 737 738 /* 739 * udp_output() may need to temporarily bind or connect the current 740 * inpcb. As such, we don't know up front what inpcb locks we will 741 * need. Do any work to decide what is needed up front before 742 * acquiring locks. 743 */ 744 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 745 if (control) 746 m_freem(control); 747 m_freem(m); 748 return EMSGSIZE; 749 } 750 751 src.sin_addr.s_addr = INADDR_ANY; 752 if (control != NULL) { 753 /* 754 * XXX: Currently, we assume all the optional information 755 * is stored in a single mbuf. 756 */ 757 if (control->m_next) { 758 m_freem(control); 759 m_freem(m); 760 return EINVAL; 761 } 762 for (; control->m_len > 0; 763 control->m_data += CMSG_ALIGN(cm->cmsg_len), 764 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 765 cm = mtod(control, struct cmsghdr *); 766 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 || 767 cm->cmsg_len > control->m_len) { 768 error = EINVAL; 769 break; 770 } 771 if (cm->cmsg_level != IPPROTO_IP) 772 continue; 773 774 switch (cm->cmsg_type) { 775 case IP_SENDSRCADDR: 776 if (cm->cmsg_len != 777 CMSG_LEN(sizeof(struct in_addr))) { 778 error = EINVAL; 779 break; 780 } 781 bzero(&src, sizeof(src)); 782 src.sin_family = AF_INET; 783 src.sin_len = sizeof(src); 784 src.sin_port = inp->inp_lport; 785 src.sin_addr = *(struct in_addr *)CMSG_DATA(cm); 786 break; 787 default: 788 error = ENOPROTOOPT; 789 break; 790 } 791 if (error) 792 break; 793 } 794 m_freem(control); 795 } 796 if (error) { 797 m_freem(m); 798 return error; 799 } 800 801 if (src.sin_addr.s_addr != INADDR_ANY || 802 addr != NULL) { 803 INP_INFO_WLOCK(&udbinfo); 804 unlock_udbinfo = 1; 805 } else 806 unlock_udbinfo = 0; 807 INP_LOCK(inp); 808 809 #ifdef MAC 810 mac_create_mbuf_from_inpcb(inp, m); 811 #endif 812 813 laddr = inp->inp_laddr; 814 lport = inp->inp_lport; 815 if (src.sin_addr.s_addr != INADDR_ANY) { 816 if (lport == 0) { 817 error = EINVAL; 818 goto release; 819 } 820 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 821 &laddr.s_addr, &lport, td->td_ucred); 822 if (error) 823 goto release; 824 } 825 826 if (addr) { 827 sin = (struct sockaddr_in *)addr; 828 if (jailed(td->td_ucred)) 829 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr); 830 if (inp->inp_faddr.s_addr != INADDR_ANY) { 831 error = EISCONN; 832 goto release; 833 } 834 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, &lport, 835 &faddr.s_addr, &fport, NULL, td->td_ucred); 836 if (error) 837 goto release; 838 839 /* Commit the local port if newly assigned. */ 840 if (inp->inp_laddr.s_addr == INADDR_ANY && 841 inp->inp_lport == 0) { 842 /* 843 * Remember addr if jailed, to prevent rebinding. 844 */ 845 if (jailed(td->td_ucred)) 846 inp->inp_laddr = laddr; 847 inp->inp_lport = lport; 848 if (in_pcbinshash(inp) != 0) { 849 inp->inp_lport = 0; 850 error = EAGAIN; 851 goto release; 852 } 853 inp->inp_flags |= INP_ANONPORT; 854 } 855 } else { 856 faddr = inp->inp_faddr; 857 fport = inp->inp_fport; 858 if (faddr.s_addr == INADDR_ANY) { 859 error = ENOTCONN; 860 goto release; 861 } 862 } 863 864 /* 865 * Calculate data length and get a mbuf for UDP, IP, and possible 866 * link-layer headers. Immediate slide the data pointer back forward 867 * since we won't use that space at this layer. 868 */ 869 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT); 870 if (m == NULL) { 871 error = ENOBUFS; 872 goto release; 873 } 874 m->m_data += max_linkhdr; 875 m->m_len -= max_linkhdr; 876 m->m_pkthdr.len -= max_linkhdr; 877 878 /* 879 * Fill in mbuf with extended UDP header 880 * and addresses and length put into network format. 881 */ 882 ui = mtod(m, struct udpiphdr *); 883 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 884 ui->ui_pr = IPPROTO_UDP; 885 ui->ui_src = laddr; 886 ui->ui_dst = faddr; 887 ui->ui_sport = lport; 888 ui->ui_dport = fport; 889 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 890 891 /* 892 * Set the Don't Fragment bit in the IP header. 893 */ 894 if (inp->inp_flags & INP_DONTFRAG) { 895 struct ip *ip; 896 ip = (struct ip *)&ui->ui_i; 897 ip->ip_off |= IP_DF; 898 } 899 900 ipflags = 0; 901 if (inp->inp_socket->so_options & SO_DONTROUTE) 902 ipflags |= IP_ROUTETOIF; 903 if (inp->inp_socket->so_options & SO_BROADCAST) 904 ipflags |= IP_ALLOWBROADCAST; 905 if (inp->inp_flags & INP_ONESBCAST) 906 ipflags |= IP_SENDONES; 907 908 /* 909 * Set up checksum and output datagram. 910 */ 911 if (udpcksum) { 912 if (inp->inp_flags & INP_ONESBCAST) 913 faddr.s_addr = INADDR_BROADCAST; 914 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 915 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 916 m->m_pkthdr.csum_flags = CSUM_UDP; 917 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 918 } else { 919 ui->ui_sum = 0; 920 } 921 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 922 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 923 ((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */ 924 udpstat.udps_opackets++; 925 926 if (unlock_udbinfo) 927 INP_INFO_WUNLOCK(&udbinfo); 928 error = ip_output(m, inp->inp_options, NULL, ipflags, 929 inp->inp_moptions, inp); 930 INP_UNLOCK(inp); 931 return (error); 932 933 release: 934 INP_UNLOCK(inp); 935 if (unlock_udbinfo) 936 INP_INFO_WUNLOCK(&udbinfo); 937 m_freem(m); 938 return (error); 939 } 940 941 u_long udp_sendspace = 9216; /* really max datagram size */ 942 /* 40 1K datagrams */ 943 SYSCTL_ULONG(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 944 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 945 946 u_long udp_recvspace = 40 * (1024 + 947 #ifdef INET6 948 sizeof(struct sockaddr_in6) 949 #else 950 sizeof(struct sockaddr_in) 951 #endif 952 ); 953 SYSCTL_ULONG(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 954 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 955 956 static void 957 udp_abort(struct socket *so) 958 { 959 struct inpcb *inp; 960 961 inp = sotoinpcb(so); 962 KASSERT(inp != NULL, ("udp_abort: inp == NULL")); 963 INP_INFO_WLOCK(&udbinfo); 964 INP_LOCK(inp); 965 if (inp->inp_faddr.s_addr != INADDR_ANY) { 966 in_pcbdisconnect(inp); 967 inp->inp_laddr.s_addr = INADDR_ANY; 968 soisdisconnected(so); 969 } 970 INP_UNLOCK(inp); 971 INP_INFO_WUNLOCK(&udbinfo); 972 } 973 974 static int 975 udp_attach(struct socket *so, int proto, struct thread *td) 976 { 977 struct inpcb *inp; 978 int error; 979 980 inp = sotoinpcb(so); 981 KASSERT(inp == NULL, ("udp_attach: inp != NULL")); 982 error = soreserve(so, udp_sendspace, udp_recvspace); 983 if (error) 984 return error; 985 INP_INFO_WLOCK(&udbinfo); 986 error = in_pcballoc(so, &udbinfo); 987 if (error) { 988 INP_INFO_WUNLOCK(&udbinfo); 989 return error; 990 } 991 992 inp = (struct inpcb *)so->so_pcb; 993 INP_INFO_WUNLOCK(&udbinfo); 994 inp->inp_vflag |= INP_IPV4; 995 inp->inp_ip_ttl = ip_defttl; 996 INP_UNLOCK(inp); 997 return 0; 998 } 999 1000 static int 1001 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 1002 { 1003 struct inpcb *inp; 1004 int error; 1005 1006 inp = sotoinpcb(so); 1007 KASSERT(inp != NULL, ("udp_bind: inp == NULL")); 1008 INP_INFO_WLOCK(&udbinfo); 1009 INP_LOCK(inp); 1010 error = in_pcbbind(inp, nam, td->td_ucred); 1011 INP_UNLOCK(inp); 1012 INP_INFO_WUNLOCK(&udbinfo); 1013 return error; 1014 } 1015 1016 static void 1017 udp_close(struct socket *so) 1018 { 1019 struct inpcb *inp; 1020 1021 inp = sotoinpcb(so); 1022 KASSERT(inp != NULL, ("udp_close: inp == NULL")); 1023 INP_INFO_WLOCK(&udbinfo); 1024 INP_LOCK(inp); 1025 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1026 in_pcbdisconnect(inp); 1027 inp->inp_laddr.s_addr = INADDR_ANY; 1028 soisdisconnected(so); 1029 } 1030 INP_UNLOCK(inp); 1031 INP_INFO_WUNLOCK(&udbinfo); 1032 } 1033 1034 static int 1035 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1036 { 1037 struct inpcb *inp; 1038 int error; 1039 struct sockaddr_in *sin; 1040 1041 inp = sotoinpcb(so); 1042 KASSERT(inp != NULL, ("udp_connect: inp == NULL")); 1043 INP_INFO_WLOCK(&udbinfo); 1044 INP_LOCK(inp); 1045 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1046 INP_UNLOCK(inp); 1047 INP_INFO_WUNLOCK(&udbinfo); 1048 return EISCONN; 1049 } 1050 sin = (struct sockaddr_in *)nam; 1051 if (jailed(td->td_ucred)) 1052 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr); 1053 error = in_pcbconnect(inp, nam, td->td_ucred); 1054 if (error == 0) 1055 soisconnected(so); 1056 INP_UNLOCK(inp); 1057 INP_INFO_WUNLOCK(&udbinfo); 1058 return error; 1059 } 1060 1061 static void 1062 udp_detach(struct socket *so) 1063 { 1064 struct inpcb *inp; 1065 1066 inp = sotoinpcb(so); 1067 KASSERT(inp != NULL, ("udp_detach: inp == NULL")); 1068 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY, 1069 ("udp_detach: not disconnected")); 1070 INP_INFO_WLOCK(&udbinfo); 1071 INP_LOCK(inp); 1072 in_pcbdetach(inp); 1073 in_pcbfree(inp); 1074 INP_INFO_WUNLOCK(&udbinfo); 1075 } 1076 1077 static int 1078 udp_disconnect(struct socket *so) 1079 { 1080 struct inpcb *inp; 1081 1082 inp = sotoinpcb(so); 1083 KASSERT(inp != NULL, ("udp_disconnect: inp == NULL")); 1084 INP_INFO_WLOCK(&udbinfo); 1085 INP_LOCK(inp); 1086 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1087 INP_INFO_WUNLOCK(&udbinfo); 1088 INP_UNLOCK(inp); 1089 return ENOTCONN; 1090 } 1091 1092 in_pcbdisconnect(inp); 1093 inp->inp_laddr.s_addr = INADDR_ANY; 1094 SOCK_LOCK(so); 1095 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1096 SOCK_UNLOCK(so); 1097 INP_UNLOCK(inp); 1098 INP_INFO_WUNLOCK(&udbinfo); 1099 return 0; 1100 } 1101 1102 static int 1103 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1104 struct mbuf *control, struct thread *td) 1105 { 1106 struct inpcb *inp; 1107 1108 inp = sotoinpcb(so); 1109 KASSERT(inp != NULL, ("udp_send: inp == NULL")); 1110 return udp_output(inp, m, addr, control, td); 1111 } 1112 1113 int 1114 udp_shutdown(struct socket *so) 1115 { 1116 struct inpcb *inp; 1117 1118 inp = sotoinpcb(so); 1119 KASSERT(inp != NULL, ("udp_shutdown: inp == NULL")); 1120 INP_LOCK(inp); 1121 socantsendmore(so); 1122 INP_UNLOCK(inp); 1123 return 0; 1124 } 1125 1126 /* 1127 * This is the wrapper function for in_setsockaddr. We just pass down 1128 * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking 1129 * here because in_setsockaddr will call malloc and might block. 1130 */ 1131 static int 1132 udp_sockaddr(struct socket *so, struct sockaddr **nam) 1133 { 1134 return (in_setsockaddr(so, nam, &udbinfo)); 1135 } 1136 1137 /* 1138 * This is the wrapper function for in_setpeeraddr. We just pass down 1139 * the pcbinfo for in_setpeeraddr to lock. 1140 */ 1141 static int 1142 udp_peeraddr(struct socket *so, struct sockaddr **nam) 1143 { 1144 return (in_setpeeraddr(so, nam, &udbinfo)); 1145 } 1146 1147 struct pr_usrreqs udp_usrreqs = { 1148 .pru_abort = udp_abort, 1149 .pru_attach = udp_attach, 1150 .pru_bind = udp_bind, 1151 .pru_connect = udp_connect, 1152 .pru_control = in_control, 1153 .pru_detach = udp_detach, 1154 .pru_disconnect = udp_disconnect, 1155 .pru_peeraddr = udp_peeraddr, 1156 .pru_send = udp_send, 1157 .pru_sosend = sosend_dgram, 1158 .pru_shutdown = udp_shutdown, 1159 .pru_sockaddr = udp_sockaddr, 1160 .pru_sosetlabel = in_pcbsosetlabel, 1161 .pru_close = udp_close, 1162 }; 1163