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 struct sockaddr_in udp_in = { sizeof(udp_in), AF_INET }; 124 #ifdef INET6 125 struct udp_in6 { 126 struct sockaddr_in6 uin6_sin; 127 u_char uin6_init_done : 1; 128 } udp_in6 = { 129 { sizeof(udp_in6.uin6_sin), AF_INET6 }, 130 0 131 }; 132 struct udp_ip6 { 133 struct ip6_hdr uip6_ip6; 134 u_char uip6_init_done : 1; 135 } udp_ip6; 136 #endif /* INET6 */ 137 138 static void udp_append(struct inpcb *last, struct ip *ip, struct mbuf *n, 139 int off); 140 #ifdef INET6 141 static void ip_2_ip6_hdr(struct ip6_hdr *ip6, struct ip *ip); 142 #endif 143 144 static int udp_detach(struct socket *so); 145 static int udp_output(struct inpcb *, struct mbuf *, struct sockaddr *, 146 struct mbuf *, struct thread *); 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, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 159 uma_zone_set_max(udbinfo.ipi_zone, maxsockets); 160 } 161 162 void 163 udp_input(m, off) 164 register struct mbuf *m; 165 int off; 166 { 167 int iphlen = off; 168 register struct ip *ip; 169 register struct udphdr *uh; 170 register struct inpcb *inp; 171 struct mbuf *opts = 0; 172 int len; 173 struct ip save_ip; 174 175 udpstat.udps_ipackets++; 176 177 /* 178 * Strip IP options, if any; should skip this, 179 * make available to user, and use on returned packets, 180 * but we don't yet have a way to check the checksum 181 * with options still present. 182 */ 183 if (iphlen > sizeof (struct ip)) { 184 ip_stripoptions(m, (struct mbuf *)0); 185 iphlen = sizeof(struct ip); 186 } 187 188 /* 189 * Get IP and UDP header together in first mbuf. 190 */ 191 ip = mtod(m, struct ip *); 192 if (m->m_len < iphlen + sizeof(struct udphdr)) { 193 if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) { 194 udpstat.udps_hdrops++; 195 return; 196 } 197 ip = mtod(m, struct ip *); 198 } 199 uh = (struct udphdr *)((caddr_t)ip + iphlen); 200 201 /* destination port of 0 is illegal, based on RFC768. */ 202 if (uh->uh_dport == 0) 203 goto badunlocked; 204 205 /* 206 * Construct sockaddr format source address. 207 * Stuff source address and datagram in user buffer. 208 */ 209 udp_in.sin_port = uh->uh_sport; 210 udp_in.sin_addr = ip->ip_src; 211 #ifdef INET6 212 udp_in6.uin6_init_done = udp_ip6.uip6_init_done = 0; 213 #endif 214 215 /* 216 * Make mbuf data length reflect UDP length. 217 * If not enough data to reflect UDP length, drop. 218 */ 219 len = ntohs((u_short)uh->uh_ulen); 220 if (ip->ip_len != len) { 221 if (len > ip->ip_len || len < sizeof(struct udphdr)) { 222 udpstat.udps_badlen++; 223 goto badunlocked; 224 } 225 m_adj(m, len - ip->ip_len); 226 /* ip->ip_len = len; */ 227 } 228 /* 229 * Save a copy of the IP header in case we want restore it 230 * for sending an ICMP error message in response. 231 */ 232 if (!blackhole) 233 save_ip = *ip; 234 235 /* 236 * Checksum extended UDP header and data. 237 */ 238 if (uh->uh_sum) { 239 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { 240 if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) 241 uh->uh_sum = m->m_pkthdr.csum_data; 242 else 243 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, 244 ip->ip_dst.s_addr, htonl((u_short)len + 245 m->m_pkthdr.csum_data + IPPROTO_UDP)); 246 uh->uh_sum ^= 0xffff; 247 } else { 248 char b[9]; 249 bcopy(((struct ipovly *)ip)->ih_x1, b, 9); 250 bzero(((struct ipovly *)ip)->ih_x1, 9); 251 ((struct ipovly *)ip)->ih_len = uh->uh_ulen; 252 uh->uh_sum = in_cksum(m, len + sizeof (struct ip)); 253 bcopy(b, ((struct ipovly *)ip)->ih_x1, 9); 254 } 255 if (uh->uh_sum) { 256 udpstat.udps_badsum++; 257 m_freem(m); 258 return; 259 } 260 } else 261 udpstat.udps_nosum++; 262 263 INP_INFO_RLOCK(&udbinfo); 264 265 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || 266 in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { 267 struct inpcb *last; 268 /* 269 * Deliver a multicast or broadcast datagram to *all* sockets 270 * for which the local and remote addresses and ports match 271 * those of the incoming datagram. This allows more than 272 * one process to receive multi/broadcasts on the same port. 273 * (This really ought to be done for unicast datagrams as 274 * well, but that would cause problems with existing 275 * applications that open both address-specific sockets and 276 * a wildcard socket listening to the same port -- they would 277 * end up receiving duplicates of every unicast datagram. 278 * Those applications open the multiple sockets to overcome an 279 * inadequacy of the UDP socket interface, but for backwards 280 * compatibility we avoid the problem here rather than 281 * fixing the interface. Maybe 4.5BSD will remedy this?) 282 */ 283 284 /* 285 * Locate pcb(s) for datagram. 286 * (Algorithm copied from raw_intr().) 287 */ 288 last = NULL; 289 LIST_FOREACH(inp, &udb, inp_list) { 290 if (inp->inp_lport != uh->uh_dport) 291 continue; 292 #ifdef INET6 293 if ((inp->inp_vflag & INP_IPV4) == 0) 294 continue; 295 #endif 296 if (inp->inp_laddr.s_addr != INADDR_ANY) { 297 if (inp->inp_laddr.s_addr != ip->ip_dst.s_addr) 298 continue; 299 } 300 if (inp->inp_faddr.s_addr != INADDR_ANY) { 301 if (inp->inp_faddr.s_addr != 302 ip->ip_src.s_addr || 303 inp->inp_fport != uh->uh_sport) 304 continue; 305 } 306 INP_LOCK(inp); 307 308 /* 309 * Check multicast packets to make sure they are only 310 * sent to sockets with multicast memberships for the 311 * packet's destination address and arrival interface 312 */ 313 #define MSHIP(_inp, n) ((_inp)->inp_moptions->imo_membership[(n)]) 314 #define NMSHIPS(_inp) ((_inp)->inp_moptions->imo_num_memberships) 315 if (strict_mcast_mship && inp->inp_moptions != NULL) { 316 int mship, foundmship = 0; 317 318 for (mship = 0; mship < NMSHIPS(inp); mship++) { 319 if (MSHIP(inp, mship)->inm_addr.s_addr 320 == ip->ip_dst.s_addr && 321 MSHIP(inp, mship)->inm_ifp 322 == m->m_pkthdr.rcvif) { 323 foundmship = 1; 324 break; 325 } 326 } 327 if (foundmship == 0) { 328 INP_UNLOCK(inp); 329 continue; 330 } 331 } 332 #undef NMSHIPS 333 #undef MSHIP 334 if (last != NULL) { 335 struct mbuf *n; 336 337 n = m_copy(m, 0, M_COPYALL); 338 if (n != NULL) 339 udp_append(last, ip, n, 340 iphlen + 341 sizeof(struct udphdr)); 342 INP_UNLOCK(last); 343 } 344 last = inp; 345 /* 346 * Don't look for additional matches if this one does 347 * not have either the SO_REUSEPORT or SO_REUSEADDR 348 * socket options set. This heuristic avoids searching 349 * through all pcbs in the common case of a non-shared 350 * port. It * assumes that an application will never 351 * clear these options after setting them. 352 */ 353 if ((last->inp_socket->so_options&(SO_REUSEPORT|SO_REUSEADDR)) == 0) 354 break; 355 } 356 357 if (last == NULL) { 358 /* 359 * No matching pcb found; discard datagram. 360 * (No need to send an ICMP Port Unreachable 361 * for a broadcast or multicast datgram.) 362 */ 363 udpstat.udps_noportbcast++; 364 goto badheadlocked; 365 } 366 INP_INFO_RUNLOCK(&udbinfo); 367 udp_append(last, ip, m, iphlen + sizeof(struct udphdr)); 368 INP_UNLOCK(last); 369 return; 370 } 371 /* 372 * Locate pcb for datagram. 373 */ 374 inp = in_pcblookup_hash(&udbinfo, ip->ip_src, uh->uh_sport, 375 ip->ip_dst, uh->uh_dport, 1, m->m_pkthdr.rcvif); 376 if (inp == NULL) { 377 if (log_in_vain) { 378 char buf[4*sizeof "123"]; 379 380 strcpy(buf, inet_ntoa(ip->ip_dst)); 381 log(LOG_INFO, 382 "Connection attempt to UDP %s:%d from %s:%d\n", 383 buf, ntohs(uh->uh_dport), inet_ntoa(ip->ip_src), 384 ntohs(uh->uh_sport)); 385 } 386 udpstat.udps_noport++; 387 if (m->m_flags & (M_BCAST | M_MCAST)) { 388 udpstat.udps_noportbcast++; 389 goto badheadlocked; 390 } 391 if (blackhole) 392 goto badheadlocked; 393 if (badport_bandlim(BANDLIM_ICMP_UNREACH) < 0) 394 goto badheadlocked; 395 *ip = save_ip; 396 ip->ip_len += iphlen; 397 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0); 398 INP_INFO_RUNLOCK(&udbinfo); 399 return; 400 } 401 INP_LOCK(inp); 402 INP_INFO_RUNLOCK(&udbinfo); 403 udp_append(inp, ip, m, iphlen + sizeof(struct udphdr)); 404 INP_UNLOCK(inp); 405 return; 406 407 badheadlocked: 408 INP_INFO_RUNLOCK(&udbinfo); 409 if (inp) 410 INP_UNLOCK(inp); 411 badunlocked: 412 m_freem(m); 413 if (opts) 414 m_freem(opts); 415 return; 416 } 417 418 #ifdef INET6 419 static void 420 ip_2_ip6_hdr(ip6, ip) 421 struct ip6_hdr *ip6; 422 struct ip *ip; 423 { 424 bzero(ip6, sizeof(*ip6)); 425 426 ip6->ip6_vfc = IPV6_VERSION; 427 ip6->ip6_plen = ip->ip_len; 428 ip6->ip6_nxt = ip->ip_p; 429 ip6->ip6_hlim = ip->ip_ttl; 430 ip6->ip6_src.s6_addr32[2] = ip6->ip6_dst.s6_addr32[2] = 431 IPV6_ADDR_INT32_SMP; 432 ip6->ip6_src.s6_addr32[3] = ip->ip_src.s_addr; 433 ip6->ip6_dst.s6_addr32[3] = ip->ip_dst.s_addr; 434 } 435 #endif 436 437 /* 438 * subroutine of udp_input(), mainly for source code readability. 439 * caller must properly init udp_ip6 and udp_in6 beforehand. 440 */ 441 static void 442 udp_append(last, ip, n, off) 443 struct inpcb *last; 444 struct ip *ip; 445 struct mbuf *n; 446 int off; 447 { 448 struct sockaddr *append_sa; 449 struct socket *so; 450 struct mbuf *opts = 0; 451 452 INP_LOCK_ASSERT(last); 453 454 #if defined(IPSEC) || defined(FAST_IPSEC) 455 /* check AH/ESP integrity. */ 456 if (ipsec4_in_reject(n, last)) { 457 #ifdef IPSEC 458 ipsecstat.in_polvio++; 459 #endif /*IPSEC*/ 460 m_freem(n); 461 return; 462 } 463 #endif /*IPSEC || FAST_IPSEC*/ 464 #ifdef MAC 465 if (mac_check_inpcb_deliver(last, n) != 0) { 466 m_freem(n); 467 return; 468 } 469 #endif 470 if (last->inp_flags & INP_CONTROLOPTS || 471 last->inp_socket->so_options & (SO_TIMESTAMP | SO_BINTIME)) { 472 #ifdef INET6 473 if (last->inp_vflag & INP_IPV6) { 474 int savedflags; 475 476 if (udp_ip6.uip6_init_done == 0) { 477 ip_2_ip6_hdr(&udp_ip6.uip6_ip6, ip); 478 udp_ip6.uip6_init_done = 1; 479 } 480 savedflags = last->inp_flags; 481 last->inp_flags &= ~INP_UNMAPPABLEOPTS; 482 ip6_savecontrol(last, n, &opts); 483 last->inp_flags = savedflags; 484 } else 485 #endif 486 ip_savecontrol(last, &opts, ip, n); 487 } 488 #ifdef INET6 489 if (last->inp_vflag & INP_IPV6) { 490 if (udp_in6.uin6_init_done == 0) { 491 in6_sin_2_v4mapsin6(&udp_in, &udp_in6.uin6_sin); 492 udp_in6.uin6_init_done = 1; 493 } 494 append_sa = (struct sockaddr *)&udp_in6.uin6_sin; 495 } else 496 #endif 497 append_sa = (struct sockaddr *)&udp_in; 498 m_adj(n, off); 499 500 so = last->inp_socket; 501 SOCKBUF_LOCK(&so->so_rcv); 502 if (sbappendaddr_locked(&so->so_rcv, append_sa, n, opts) == 0) { 503 m_freem(n); 504 if (opts) 505 m_freem(opts); 506 udpstat.udps_fullsock++; 507 SOCKBUF_UNLOCK(&so->so_rcv); 508 } else 509 sorwakeup_locked(so); 510 } 511 512 /* 513 * Notify a udp user of an asynchronous error; 514 * just wake up so that he can collect error status. 515 */ 516 struct inpcb * 517 udp_notify(inp, errno) 518 register struct inpcb *inp; 519 int errno; 520 { 521 inp->inp_socket->so_error = errno; 522 sorwakeup(inp->inp_socket); 523 sowwakeup(inp->inp_socket); 524 return inp; 525 } 526 527 void 528 udp_ctlinput(cmd, sa, vip) 529 int cmd; 530 struct sockaddr *sa; 531 void *vip; 532 { 533 struct ip *ip = vip; 534 struct udphdr *uh; 535 struct inpcb *(*notify)(struct inpcb *, int) = udp_notify; 536 struct in_addr faddr; 537 struct inpcb *inp; 538 int s; 539 540 faddr = ((struct sockaddr_in *)sa)->sin_addr; 541 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 542 return; 543 544 /* 545 * Redirects don't need to be handled up here. 546 */ 547 if (PRC_IS_REDIRECT(cmd)) 548 return; 549 /* 550 * Hostdead is ugly because it goes linearly through all PCBs. 551 * XXX: We never get this from ICMP, otherwise it makes an 552 * excellent DoS attack on machines with many connections. 553 */ 554 if (cmd == PRC_HOSTDEAD) 555 ip = 0; 556 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) 557 return; 558 if (ip) { 559 s = splnet(); 560 uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2)); 561 INP_INFO_RLOCK(&udbinfo); 562 inp = in_pcblookup_hash(&udbinfo, faddr, uh->uh_dport, 563 ip->ip_src, uh->uh_sport, 0, NULL); 564 if (inp != NULL) { 565 INP_LOCK(inp); 566 if (inp->inp_socket != NULL) { 567 (*notify)(inp, inetctlerrmap[cmd]); 568 } 569 INP_UNLOCK(inp); 570 } 571 INP_INFO_RUNLOCK(&udbinfo); 572 splx(s); 573 } else 574 in_pcbnotifyall(&udbinfo, faddr, inetctlerrmap[cmd], notify); 575 } 576 577 static int 578 udp_pcblist(SYSCTL_HANDLER_ARGS) 579 { 580 int error, i, n, s; 581 struct inpcb *inp, **inp_list; 582 inp_gen_t gencnt; 583 struct xinpgen xig; 584 585 /* 586 * The process of preparing the TCB list is too time-consuming and 587 * resource-intensive to repeat twice on every request. 588 */ 589 if (req->oldptr == 0) { 590 n = udbinfo.ipi_count; 591 req->oldidx = 2 * (sizeof xig) 592 + (n + n/8) * sizeof(struct xinpcb); 593 return 0; 594 } 595 596 if (req->newptr != 0) 597 return EPERM; 598 599 /* 600 * OK, now we're committed to doing something. 601 */ 602 s = splnet(); 603 INP_INFO_RLOCK(&udbinfo); 604 gencnt = udbinfo.ipi_gencnt; 605 n = udbinfo.ipi_count; 606 INP_INFO_RUNLOCK(&udbinfo); 607 splx(s); 608 609 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig) 610 + n * sizeof(struct xinpcb)); 611 if (error != 0) 612 return (error); 613 614 xig.xig_len = sizeof xig; 615 xig.xig_count = n; 616 xig.xig_gen = gencnt; 617 xig.xig_sogen = so_gencnt; 618 error = SYSCTL_OUT(req, &xig, sizeof xig); 619 if (error) 620 return error; 621 622 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 623 if (inp_list == 0) 624 return ENOMEM; 625 626 s = splnet(); 627 INP_INFO_RLOCK(&udbinfo); 628 for (inp = LIST_FIRST(udbinfo.listhead), i = 0; inp && i < n; 629 inp = LIST_NEXT(inp, inp_list)) { 630 INP_LOCK(inp); 631 if (inp->inp_gencnt <= gencnt && 632 cr_canseesocket(req->td->td_ucred, inp->inp_socket) == 0) 633 inp_list[i++] = inp; 634 INP_UNLOCK(inp); 635 } 636 INP_INFO_RUNLOCK(&udbinfo); 637 splx(s); 638 n = i; 639 640 error = 0; 641 for (i = 0; i < n; i++) { 642 inp = inp_list[i]; 643 if (inp->inp_gencnt <= gencnt) { 644 struct xinpcb xi; 645 xi.xi_len = sizeof xi; 646 /* XXX should avoid extra copy */ 647 bcopy(inp, &xi.xi_inp, sizeof *inp); 648 if (inp->inp_socket) 649 sotoxsocket(inp->inp_socket, &xi.xi_socket); 650 xi.xi_inp.inp_gencnt = inp->inp_gencnt; 651 error = SYSCTL_OUT(req, &xi, sizeof xi); 652 } 653 } 654 if (!error) { 655 /* 656 * Give the user an updated idea of our state. 657 * If the generation differs from what we told 658 * her before, she knows that something happened 659 * while we were processing this request, and it 660 * might be necessary to retry. 661 */ 662 s = splnet(); 663 INP_INFO_RLOCK(&udbinfo); 664 xig.xig_gen = udbinfo.ipi_gencnt; 665 xig.xig_sogen = so_gencnt; 666 xig.xig_count = udbinfo.ipi_count; 667 INP_INFO_RUNLOCK(&udbinfo); 668 splx(s); 669 error = SYSCTL_OUT(req, &xig, sizeof xig); 670 } 671 free(inp_list, M_TEMP); 672 return error; 673 } 674 675 SYSCTL_PROC(_net_inet_udp, UDPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, 676 udp_pcblist, "S,xinpcb", "List of active UDP sockets"); 677 678 static int 679 udp_getcred(SYSCTL_HANDLER_ARGS) 680 { 681 struct xucred xuc; 682 struct sockaddr_in addrs[2]; 683 struct inpcb *inp; 684 int error, s; 685 686 error = suser_cred(req->td->td_ucred, SUSER_ALLOWJAIL); 687 if (error) 688 return (error); 689 error = SYSCTL_IN(req, addrs, sizeof(addrs)); 690 if (error) 691 return (error); 692 s = splnet(); 693 INP_INFO_RLOCK(&udbinfo); 694 inp = in_pcblookup_hash(&udbinfo, addrs[1].sin_addr, addrs[1].sin_port, 695 addrs[0].sin_addr, addrs[0].sin_port, 1, NULL); 696 if (inp == NULL || inp->inp_socket == NULL) { 697 error = ENOENT; 698 goto out; 699 } 700 error = cr_canseesocket(req->td->td_ucred, inp->inp_socket); 701 if (error) 702 goto out; 703 cru2x(inp->inp_socket->so_cred, &xuc); 704 out: 705 INP_INFO_RUNLOCK(&udbinfo); 706 splx(s); 707 if (error == 0) 708 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred)); 709 return (error); 710 } 711 712 SYSCTL_PROC(_net_inet_udp, OID_AUTO, getcred, 713 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, 714 udp_getcred, "S,xucred", "Get the xucred of a UDP connection"); 715 716 static int 717 udp_output(inp, m, addr, control, td) 718 register struct inpcb *inp; 719 struct mbuf *m; 720 struct sockaddr *addr; 721 struct mbuf *control; 722 struct thread *td; 723 { 724 register struct udpiphdr *ui; 725 register int len = m->m_pkthdr.len; 726 struct in_addr faddr, laddr; 727 struct cmsghdr *cm; 728 struct sockaddr_in *sin, src; 729 int error = 0; 730 int ipflags; 731 u_short fport, lport; 732 int unlock_udbinfo; 733 734 /* 735 * udp_output() may need to temporarily bind or connect the current 736 * inpcb. As such, we don't know up front what inpcb locks we will 737 * need. Do any work to decide what is needed up front before 738 * acquiring locks. 739 */ 740 if (len + sizeof(struct udpiphdr) > IP_MAXPACKET) { 741 if (control) 742 m_freem(control); 743 m_freem(m); 744 return EMSGSIZE; 745 } 746 747 src.sin_addr.s_addr = INADDR_ANY; 748 if (control != NULL) { 749 /* 750 * XXX: Currently, we assume all the optional information 751 * is stored in a single mbuf. 752 */ 753 if (control->m_next) { 754 m_freem(control); 755 m_freem(m); 756 return EINVAL; 757 } 758 for (; control->m_len > 0; 759 control->m_data += CMSG_ALIGN(cm->cmsg_len), 760 control->m_len -= CMSG_ALIGN(cm->cmsg_len)) { 761 cm = mtod(control, struct cmsghdr *); 762 if (control->m_len < sizeof(*cm) || cm->cmsg_len == 0 || 763 cm->cmsg_len > control->m_len) { 764 error = EINVAL; 765 break; 766 } 767 if (cm->cmsg_level != IPPROTO_IP) 768 continue; 769 770 switch (cm->cmsg_type) { 771 case IP_SENDSRCADDR: 772 if (cm->cmsg_len != 773 CMSG_LEN(sizeof(struct in_addr))) { 774 error = EINVAL; 775 break; 776 } 777 bzero(&src, sizeof(src)); 778 src.sin_family = AF_INET; 779 src.sin_len = sizeof(src); 780 src.sin_port = inp->inp_lport; 781 src.sin_addr = *(struct in_addr *)CMSG_DATA(cm); 782 break; 783 default: 784 error = ENOPROTOOPT; 785 break; 786 } 787 if (error) 788 break; 789 } 790 m_freem(control); 791 } 792 if (error) { 793 m_freem(m); 794 return error; 795 } 796 797 if (src.sin_addr.s_addr != INADDR_ANY || 798 addr != NULL) { 799 INP_INFO_WLOCK(&udbinfo); 800 unlock_udbinfo = 1; 801 } else 802 unlock_udbinfo = 0; 803 INP_LOCK(inp); 804 805 #ifdef MAC 806 mac_create_mbuf_from_inpcb(inp, m); 807 #endif 808 809 laddr = inp->inp_laddr; 810 lport = inp->inp_lport; 811 if (src.sin_addr.s_addr != INADDR_ANY) { 812 if (lport == 0) { 813 error = EINVAL; 814 goto release; 815 } 816 error = in_pcbbind_setup(inp, (struct sockaddr *)&src, 817 &laddr.s_addr, &lport, td->td_ucred); 818 if (error) 819 goto release; 820 } 821 822 if (addr) { 823 sin = (struct sockaddr_in *)addr; 824 if (td && jailed(td->td_ucred)) 825 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr); 826 if (inp->inp_faddr.s_addr != INADDR_ANY) { 827 error = EISCONN; 828 goto release; 829 } 830 error = in_pcbconnect_setup(inp, addr, &laddr.s_addr, &lport, 831 &faddr.s_addr, &fport, NULL, td->td_ucred); 832 if (error) 833 goto release; 834 835 /* Commit the local port if newly assigned. */ 836 if (inp->inp_laddr.s_addr == INADDR_ANY && 837 inp->inp_lport == 0) { 838 inp->inp_lport = lport; 839 if (in_pcbinshash(inp) != 0) { 840 inp->inp_lport = 0; 841 error = EAGAIN; 842 goto release; 843 } 844 inp->inp_flags |= INP_ANONPORT; 845 } 846 } else { 847 faddr = inp->inp_faddr; 848 fport = inp->inp_fport; 849 if (faddr.s_addr == INADDR_ANY) { 850 error = ENOTCONN; 851 goto release; 852 } 853 } 854 855 /* 856 * Calculate data length and get a mbuf for UDP, IP, and possible 857 * link-layer headers. Immediate slide the data pointer back forward 858 * since we won't use that space at this layer. 859 */ 860 M_PREPEND(m, sizeof(struct udpiphdr) + max_linkhdr, M_DONTWAIT); 861 if (m == NULL) { 862 error = ENOBUFS; 863 goto release; 864 } 865 m->m_data += max_linkhdr; 866 m->m_len -= max_linkhdr; 867 m->m_pkthdr.len -= max_linkhdr; 868 869 /* 870 * Fill in mbuf with extended UDP header 871 * and addresses and length put into network format. 872 */ 873 ui = mtod(m, struct udpiphdr *); 874 bzero(ui->ui_x1, sizeof(ui->ui_x1)); /* XXX still needed? */ 875 ui->ui_pr = IPPROTO_UDP; 876 ui->ui_src = laddr; 877 ui->ui_dst = faddr; 878 ui->ui_sport = lport; 879 ui->ui_dport = fport; 880 ui->ui_ulen = htons((u_short)len + sizeof(struct udphdr)); 881 882 ipflags = inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST); 883 if (inp->inp_flags & INP_ONESBCAST) 884 ipflags |= IP_SENDONES; 885 886 /* 887 * Set up checksum and output datagram. 888 */ 889 if (udpcksum) { 890 if (inp->inp_flags & INP_ONESBCAST) 891 faddr.s_addr = INADDR_BROADCAST; 892 ui->ui_sum = in_pseudo(ui->ui_src.s_addr, faddr.s_addr, 893 htons((u_short)len + sizeof(struct udphdr) + IPPROTO_UDP)); 894 m->m_pkthdr.csum_flags = CSUM_UDP; 895 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); 896 } else { 897 ui->ui_sum = 0; 898 } 899 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 900 ((struct ip *)ui)->ip_ttl = inp->inp_ip_ttl; /* XXX */ 901 ((struct ip *)ui)->ip_tos = inp->inp_ip_tos; /* XXX */ 902 udpstat.udps_opackets++; 903 904 if (unlock_udbinfo) 905 INP_INFO_WUNLOCK(&udbinfo); 906 error = ip_output(m, inp->inp_options, NULL, ipflags, 907 inp->inp_moptions, inp); 908 INP_UNLOCK(inp); 909 return (error); 910 911 release: 912 INP_UNLOCK(inp); 913 if (unlock_udbinfo) 914 INP_INFO_WUNLOCK(&udbinfo); 915 m_freem(m); 916 return (error); 917 } 918 919 u_long udp_sendspace = 9216; /* really max datagram size */ 920 /* 40 1K datagrams */ 921 SYSCTL_INT(_net_inet_udp, UDPCTL_MAXDGRAM, maxdgram, CTLFLAG_RW, 922 &udp_sendspace, 0, "Maximum outgoing UDP datagram size"); 923 924 u_long udp_recvspace = 40 * (1024 + 925 #ifdef INET6 926 sizeof(struct sockaddr_in6) 927 #else 928 sizeof(struct sockaddr_in) 929 #endif 930 ); 931 SYSCTL_INT(_net_inet_udp, UDPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 932 &udp_recvspace, 0, "Maximum space for incoming UDP datagrams"); 933 934 static int 935 udp_abort(struct socket *so) 936 { 937 struct inpcb *inp; 938 int s; 939 940 INP_INFO_WLOCK(&udbinfo); 941 inp = sotoinpcb(so); 942 if (inp == 0) { 943 INP_INFO_WUNLOCK(&udbinfo); 944 return EINVAL; /* ??? possible? panic instead? */ 945 } 946 INP_LOCK(inp); 947 soisdisconnected(so); 948 s = splnet(); 949 in_pcbdetach(inp); 950 INP_INFO_WUNLOCK(&udbinfo); 951 splx(s); 952 return 0; 953 } 954 955 static int 956 udp_attach(struct socket *so, int proto, struct thread *td) 957 { 958 struct inpcb *inp; 959 int s, 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 error = soreserve(so, udp_sendspace, udp_recvspace); 968 if (error) { 969 INP_INFO_WUNLOCK(&udbinfo); 970 return error; 971 } 972 s = splnet(); 973 error = in_pcballoc(so, &udbinfo, "udpinp"); 974 splx(s); 975 if (error) { 976 INP_INFO_WUNLOCK(&udbinfo); 977 return error; 978 } 979 980 inp = (struct inpcb *)so->so_pcb; 981 INP_LOCK(inp); 982 INP_INFO_WUNLOCK(&udbinfo); 983 inp->inp_vflag |= INP_IPV4; 984 inp->inp_ip_ttl = ip_defttl; 985 INP_UNLOCK(inp); 986 return 0; 987 } 988 989 static int 990 udp_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 991 { 992 struct inpcb *inp; 993 int s, error; 994 995 INP_INFO_WLOCK(&udbinfo); 996 inp = sotoinpcb(so); 997 if (inp == 0) { 998 INP_INFO_WUNLOCK(&udbinfo); 999 return EINVAL; 1000 } 1001 INP_LOCK(inp); 1002 s = splnet(); 1003 error = in_pcbbind(inp, nam, td->td_ucred); 1004 splx(s); 1005 INP_UNLOCK(inp); 1006 INP_INFO_WUNLOCK(&udbinfo); 1007 return error; 1008 } 1009 1010 static int 1011 udp_connect(struct socket *so, struct sockaddr *nam, struct thread *td) 1012 { 1013 struct inpcb *inp; 1014 int s, error; 1015 struct sockaddr_in *sin; 1016 1017 INP_INFO_WLOCK(&udbinfo); 1018 inp = sotoinpcb(so); 1019 if (inp == 0) { 1020 INP_INFO_WUNLOCK(&udbinfo); 1021 return EINVAL; 1022 } 1023 INP_LOCK(inp); 1024 if (inp->inp_faddr.s_addr != INADDR_ANY) { 1025 INP_UNLOCK(inp); 1026 INP_INFO_WUNLOCK(&udbinfo); 1027 return EISCONN; 1028 } 1029 s = splnet(); 1030 sin = (struct sockaddr_in *)nam; 1031 if (td && jailed(td->td_ucred)) 1032 prison_remote_ip(td->td_ucred, 0, &sin->sin_addr.s_addr); 1033 error = in_pcbconnect(inp, nam, td->td_ucred); 1034 splx(s); 1035 if (error == 0) 1036 soisconnected(so); 1037 INP_UNLOCK(inp); 1038 INP_INFO_WUNLOCK(&udbinfo); 1039 return error; 1040 } 1041 1042 static int 1043 udp_detach(struct socket *so) 1044 { 1045 struct inpcb *inp; 1046 int s; 1047 1048 INP_INFO_WLOCK(&udbinfo); 1049 inp = sotoinpcb(so); 1050 if (inp == 0) { 1051 INP_INFO_WUNLOCK(&udbinfo); 1052 return EINVAL; 1053 } 1054 INP_LOCK(inp); 1055 s = splnet(); 1056 in_pcbdetach(inp); 1057 INP_INFO_WUNLOCK(&udbinfo); 1058 splx(s); 1059 return 0; 1060 } 1061 1062 static int 1063 udp_disconnect(struct socket *so) 1064 { 1065 struct inpcb *inp; 1066 int s; 1067 1068 INP_INFO_WLOCK(&udbinfo); 1069 inp = sotoinpcb(so); 1070 if (inp == 0) { 1071 INP_INFO_WUNLOCK(&udbinfo); 1072 return EINVAL; 1073 } 1074 INP_LOCK(inp); 1075 if (inp->inp_faddr.s_addr == INADDR_ANY) { 1076 INP_INFO_WUNLOCK(&udbinfo); 1077 INP_UNLOCK(inp); 1078 return ENOTCONN; 1079 } 1080 1081 s = splnet(); 1082 in_pcbdisconnect(inp); 1083 inp->inp_laddr.s_addr = INADDR_ANY; 1084 INP_UNLOCK(inp); 1085 INP_INFO_WUNLOCK(&udbinfo); 1086 splx(s); 1087 so->so_state &= ~SS_ISCONNECTED; /* XXX */ 1088 return 0; 1089 } 1090 1091 static int 1092 udp_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *addr, 1093 struct mbuf *control, struct thread *td) 1094 { 1095 struct inpcb *inp; 1096 1097 inp = sotoinpcb(so); 1098 return udp_output(inp, m, addr, control, td); 1099 } 1100 1101 int 1102 udp_shutdown(struct socket *so) 1103 { 1104 struct inpcb *inp; 1105 1106 INP_INFO_RLOCK(&udbinfo); 1107 inp = sotoinpcb(so); 1108 if (inp == 0) { 1109 INP_INFO_RUNLOCK(&udbinfo); 1110 return EINVAL; 1111 } 1112 INP_LOCK(inp); 1113 INP_INFO_RUNLOCK(&udbinfo); 1114 socantsendmore(so); 1115 INP_UNLOCK(inp); 1116 return 0; 1117 } 1118 1119 /* 1120 * This is the wrapper function for in_setsockaddr. We just pass down 1121 * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking 1122 * here because in_setsockaddr will call malloc and might block. 1123 */ 1124 static int 1125 udp_sockaddr(struct socket *so, struct sockaddr **nam) 1126 { 1127 return (in_setsockaddr(so, nam, &udbinfo)); 1128 } 1129 1130 /* 1131 * This is the wrapper function for in_setpeeraddr. We just pass down 1132 * the pcbinfo for in_setpeeraddr to lock. 1133 */ 1134 static int 1135 udp_peeraddr(struct socket *so, struct sockaddr **nam) 1136 { 1137 return (in_setpeeraddr(so, nam, &udbinfo)); 1138 } 1139 1140 struct pr_usrreqs udp_usrreqs = { 1141 udp_abort, pru_accept_notsupp, udp_attach, udp_bind, udp_connect, 1142 pru_connect2_notsupp, in_control, udp_detach, udp_disconnect, 1143 pru_listen_notsupp, udp_peeraddr, pru_rcvd_notsupp, 1144 pru_rcvoob_notsupp, udp_send, pru_sense_null, udp_shutdown, 1145 udp_sockaddr, sosend, soreceive, sopoll, in_pcbsosetlabel 1146 }; 1147