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