1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1993 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 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 #include "opt_sctp.h" 36 #ifndef INET 37 #error "IPDIVERT requires INET" 38 #endif 39 40 #include <sys/param.h> 41 #include <sys/eventhandler.h> 42 #include <sys/kernel.h> 43 #include <sys/lock.h> 44 #include <sys/malloc.h> 45 #include <sys/mbuf.h> 46 #include <sys/module.h> 47 #include <sys/kernel.h> 48 #include <sys/priv.h> 49 #include <sys/proc.h> 50 #include <sys/protosw.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 #include <sys/sysctl.h> 54 #include <net/vnet.h> 55 56 #include <net/if.h> 57 #include <net/if_var.h> 58 #include <net/netisr.h> 59 60 #include <netinet/in.h> 61 #include <netinet/in_pcb.h> 62 #include <netinet/in_systm.h> 63 #include <netinet/in_var.h> 64 #include <netinet/ip.h> 65 #include <netinet/ip_var.h> 66 #ifdef INET6 67 #include <netinet/ip6.h> 68 #include <netinet6/ip6_var.h> 69 #endif 70 #ifdef SCTP 71 #include <netinet/sctp_crc32.h> 72 #endif 73 74 #include <security/mac/mac_framework.h> 75 76 /* 77 * Divert sockets 78 */ 79 80 /* 81 * Allocate enough space to hold a full IP packet 82 */ 83 #define DIVSNDQ (65536 + 100) 84 #define DIVRCVQ (65536 + 100) 85 86 /* 87 * Divert sockets work in conjunction with ipfw or other packet filters, 88 * see the divert(4) manpage for features. 89 * Packets are selected by the packet filter and tagged with an 90 * MTAG_IPFW_RULE tag carrying the 'divert port' number (as set by 91 * the packet filter) and information on the matching filter rule for 92 * subsequent reinjection. The divert_port is used to put the packet 93 * on the corresponding divert socket, while the rule number is passed 94 * up (at least partially) as the sin_port in the struct sockaddr. 95 * 96 * Packets written to the divert socket carry in sin_addr a 97 * destination address, and in sin_port the number of the filter rule 98 * after which to continue processing. 99 * If the destination address is INADDR_ANY, the packet is treated as 100 * as outgoing and sent to ip_output(); otherwise it is treated as 101 * incoming and sent to ip_input(). 102 * Further, sin_zero carries some information on the interface, 103 * which can be used in the reinject -- see comments in the code. 104 * 105 * On reinjection, processing in ip_input() and ip_output() 106 * will be exactly the same as for the original packet, except that 107 * packet filter processing will start at the rule number after the one 108 * written in the sin_port (ipfw does not allow a rule #0, so sin_port=0 109 * will apply the entire ruleset to the packet). 110 */ 111 112 /* Internal variables. */ 113 static VNET_DEFINE(struct inpcbhead, divcb); 114 static VNET_DEFINE(struct inpcbinfo, divcbinfo); 115 116 #define V_divcb VNET(divcb) 117 #define V_divcbinfo VNET(divcbinfo) 118 119 static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */ 120 static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */ 121 122 static eventhandler_tag ip_divert_event_tag; 123 124 /* 125 * Initialize divert connection block queue. 126 */ 127 static void 128 div_zone_change(void *tag) 129 { 130 131 uma_zone_set_max(V_divcbinfo.ipi_zone, maxsockets); 132 } 133 134 static int 135 div_inpcb_init(void *mem, int size, int flags) 136 { 137 struct inpcb *inp = mem; 138 139 INP_LOCK_INIT(inp, "inp", "divinp"); 140 return (0); 141 } 142 143 static void 144 div_inpcb_fini(void *mem, int size) 145 { 146 struct inpcb *inp = mem; 147 148 INP_LOCK_DESTROY(inp); 149 } 150 151 static void 152 div_init(void) 153 { 154 155 /* 156 * XXX We don't use the hash list for divert IP, but it's easier to 157 * allocate one-entry hash lists than it is to check all over the 158 * place for hashbase == NULL. 159 */ 160 in_pcbinfo_init(&V_divcbinfo, "div", &V_divcb, 1, 1, "divcb", 161 div_inpcb_init, div_inpcb_fini, UMA_ZONE_NOFREE, 162 IPI_HASHFIELDS_NONE); 163 } 164 165 static void 166 div_destroy(void) 167 { 168 169 in_pcbinfo_destroy(&V_divcbinfo); 170 } 171 172 /* 173 * IPPROTO_DIVERT is not in the real IP protocol number space; this 174 * function should never be called. Just in case, drop any packets. 175 */ 176 static int 177 div_input(struct mbuf **mp, int *offp, int proto) 178 { 179 struct mbuf *m = *mp; 180 181 KMOD_IPSTAT_INC(ips_noproto); 182 m_freem(m); 183 return (IPPROTO_DONE); 184 } 185 186 /* 187 * Divert a packet by passing it up to the divert socket at port 'port'. 188 * 189 * Setup generic address and protocol structures for div_input routine, 190 * then pass them along with mbuf chain. 191 */ 192 static void 193 divert_packet(struct mbuf *m, int incoming) 194 { 195 struct ip *ip; 196 struct inpcb *inp; 197 struct socket *sa; 198 u_int16_t nport; 199 struct sockaddr_in divsrc; 200 struct m_tag *mtag; 201 202 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL); 203 if (mtag == NULL) { 204 m_freem(m); 205 return; 206 } 207 /* Assure header */ 208 if (m->m_len < sizeof(struct ip) && 209 (m = m_pullup(m, sizeof(struct ip))) == 0) 210 return; 211 ip = mtod(m, struct ip *); 212 213 /* Delayed checksums are currently not compatible with divert. */ 214 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 215 in_delayed_cksum(m); 216 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 217 } 218 #ifdef SCTP 219 if (m->m_pkthdr.csum_flags & CSUM_SCTP) { 220 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2)); 221 m->m_pkthdr.csum_flags &= ~CSUM_SCTP; 222 } 223 #endif 224 bzero(&divsrc, sizeof(divsrc)); 225 divsrc.sin_len = sizeof(divsrc); 226 divsrc.sin_family = AF_INET; 227 /* record matching rule, in host format */ 228 divsrc.sin_port = ((struct ipfw_rule_ref *)(mtag+1))->rulenum; 229 /* 230 * Record receive interface address, if any. 231 * But only for incoming packets. 232 */ 233 if (incoming) { 234 struct ifaddr *ifa; 235 struct ifnet *ifp; 236 237 /* Sanity check */ 238 M_ASSERTPKTHDR(m); 239 240 /* Find IP address for receive interface */ 241 ifp = m->m_pkthdr.rcvif; 242 if_addr_rlock(ifp); 243 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 244 if (ifa->ifa_addr->sa_family != AF_INET) 245 continue; 246 divsrc.sin_addr = 247 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr; 248 break; 249 } 250 if_addr_runlock(ifp); 251 } 252 /* 253 * Record the incoming interface name whenever we have one. 254 */ 255 if (m->m_pkthdr.rcvif) { 256 /* 257 * Hide the actual interface name in there in the 258 * sin_zero array. XXX This needs to be moved to a 259 * different sockaddr type for divert, e.g. 260 * sockaddr_div with multiple fields like 261 * sockaddr_dl. Presently we have only 7 bytes 262 * but that will do for now as most interfaces 263 * are 4 or less + 2 or less bytes for unit. 264 * There is probably a faster way of doing this, 265 * possibly taking it from the sockaddr_dl on the iface. 266 * This solves the problem of a P2P link and a LAN interface 267 * having the same address, which can result in the wrong 268 * interface being assigned to the packet when fed back 269 * into the divert socket. Theoretically if the daemon saves 270 * and re-uses the sockaddr_in as suggested in the man pages, 271 * this iface name will come along for the ride. 272 * (see div_output for the other half of this.) 273 */ 274 strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname, 275 sizeof(divsrc.sin_zero)); 276 } 277 278 /* Put packet on socket queue, if any */ 279 sa = NULL; 280 nport = htons((u_int16_t)(((struct ipfw_rule_ref *)(mtag+1))->info)); 281 INP_INFO_RLOCK(&V_divcbinfo); 282 LIST_FOREACH(inp, &V_divcb, inp_list) { 283 /* XXX why does only one socket match? */ 284 if (inp->inp_lport == nport) { 285 INP_RLOCK(inp); 286 sa = inp->inp_socket; 287 SOCKBUF_LOCK(&sa->so_rcv); 288 if (sbappendaddr_locked(&sa->so_rcv, 289 (struct sockaddr *)&divsrc, m, 290 (struct mbuf *)0) == 0) { 291 SOCKBUF_UNLOCK(&sa->so_rcv); 292 sa = NULL; /* force mbuf reclaim below */ 293 } else 294 sorwakeup_locked(sa); 295 INP_RUNLOCK(inp); 296 break; 297 } 298 } 299 INP_INFO_RUNLOCK(&V_divcbinfo); 300 if (sa == NULL) { 301 m_freem(m); 302 KMOD_IPSTAT_INC(ips_noproto); 303 KMOD_IPSTAT_DEC(ips_delivered); 304 } 305 } 306 307 /* 308 * Deliver packet back into the IP processing machinery. 309 * 310 * If no address specified, or address is 0.0.0.0, send to ip_output(); 311 * otherwise, send to ip_input() and mark as having been received on 312 * the interface with that address. 313 */ 314 static int 315 div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin, 316 struct mbuf *control) 317 { 318 struct ip *const ip = mtod(m, struct ip *); 319 struct m_tag *mtag; 320 struct ipfw_rule_ref *dt; 321 int error = 0; 322 323 /* 324 * An mbuf may hasn't come from userland, but we pretend 325 * that it has. 326 */ 327 m->m_pkthdr.rcvif = NULL; 328 m->m_nextpkt = NULL; 329 M_SETFIB(m, so->so_fibnum); 330 331 if (control) 332 m_freem(control); /* XXX */ 333 334 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL); 335 if (mtag == NULL) { 336 /* this should be normal */ 337 mtag = m_tag_alloc(MTAG_IPFW_RULE, 0, 338 sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO); 339 if (mtag == NULL) { 340 error = ENOBUFS; 341 goto cantsend; 342 } 343 m_tag_prepend(m, mtag); 344 } 345 dt = (struct ipfw_rule_ref *)(mtag+1); 346 347 /* Loopback avoidance and state recovery */ 348 if (sin) { 349 int i; 350 351 /* set the starting point. We provide a non-zero slot, 352 * but a non_matching chain_id to skip that info and use 353 * the rulenum/rule_id. 354 */ 355 dt->slot = 1; /* dummy, chain_id is invalid */ 356 dt->chain_id = 0; 357 dt->rulenum = sin->sin_port+1; /* host format ? */ 358 dt->rule_id = 0; 359 /* 360 * Find receive interface with the given name, stuffed 361 * (if it exists) in the sin_zero[] field. 362 * The name is user supplied data so don't trust its size 363 * or that it is zero terminated. 364 */ 365 for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++) 366 ; 367 if ( i > 0 && i < sizeof(sin->sin_zero)) 368 m->m_pkthdr.rcvif = ifunit(sin->sin_zero); 369 } 370 371 /* Reinject packet into the system as incoming or outgoing */ 372 if (!sin || sin->sin_addr.s_addr == 0) { 373 struct mbuf *options = NULL; 374 struct inpcb *inp; 375 376 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_OUT; 377 inp = sotoinpcb(so); 378 INP_RLOCK(inp); 379 switch (ip->ip_v) { 380 case IPVERSION: 381 /* 382 * Don't allow both user specified and setsockopt 383 * options, and don't allow packet length sizes that 384 * will crash. 385 */ 386 if ((((ip->ip_hl << 2) != sizeof(struct ip)) && 387 inp->inp_options != NULL) || 388 ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) { 389 error = EINVAL; 390 INP_RUNLOCK(inp); 391 goto cantsend; 392 } 393 break; 394 #ifdef INET6 395 case IPV6_VERSION >> 4: 396 { 397 struct ip6_hdr *const ip6 = mtod(m, struct ip6_hdr *); 398 399 /* Don't allow packet length sizes that will crash */ 400 if (((u_short)ntohs(ip6->ip6_plen) > m->m_pkthdr.len)) { 401 error = EINVAL; 402 INP_RUNLOCK(inp); 403 goto cantsend; 404 } 405 break; 406 } 407 #endif 408 default: 409 error = EINVAL; 410 INP_RUNLOCK(inp); 411 goto cantsend; 412 } 413 414 /* Send packet to output processing */ 415 KMOD_IPSTAT_INC(ips_rawout); /* XXX */ 416 417 #ifdef MAC 418 mac_inpcb_create_mbuf(inp, m); 419 #endif 420 /* 421 * Get ready to inject the packet into ip_output(). 422 * Just in case socket options were specified on the 423 * divert socket, we duplicate them. This is done 424 * to avoid having to hold the PCB locks over the call 425 * to ip_output(), as doing this results in a number of 426 * lock ordering complexities. 427 * 428 * Note that we set the multicast options argument for 429 * ip_output() to NULL since it should be invariant that 430 * they are not present. 431 */ 432 KASSERT(inp->inp_moptions == NULL, 433 ("multicast options set on a divert socket")); 434 /* 435 * XXXCSJP: It is unclear to me whether or not it makes 436 * sense for divert sockets to have options. However, 437 * for now we will duplicate them with the INP locks 438 * held so we can use them in ip_output() without 439 * requring a reference to the pcb. 440 */ 441 if (inp->inp_options != NULL) { 442 options = m_dup(inp->inp_options, M_NOWAIT); 443 if (options == NULL) { 444 INP_RUNLOCK(inp); 445 error = ENOBUFS; 446 goto cantsend; 447 } 448 } 449 INP_RUNLOCK(inp); 450 451 switch (ip->ip_v) { 452 case IPVERSION: 453 error = ip_output(m, options, NULL, 454 ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0) 455 | IP_ALLOWBROADCAST | IP_RAWOUTPUT, NULL, NULL); 456 break; 457 #ifdef INET6 458 case IPV6_VERSION >> 4: 459 error = ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL); 460 break; 461 #endif 462 } 463 if (options != NULL) 464 m_freem(options); 465 } else { 466 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_IN; 467 if (m->m_pkthdr.rcvif == NULL) { 468 /* 469 * No luck with the name, check by IP address. 470 * Clear the port and the ifname to make sure 471 * there are no distractions for ifa_ifwithaddr. 472 */ 473 struct ifaddr *ifa; 474 475 bzero(sin->sin_zero, sizeof(sin->sin_zero)); 476 sin->sin_port = 0; 477 ifa = ifa_ifwithaddr((struct sockaddr *) sin); 478 if (ifa == NULL) { 479 error = EADDRNOTAVAIL; 480 goto cantsend; 481 } 482 m->m_pkthdr.rcvif = ifa->ifa_ifp; 483 ifa_free(ifa); 484 } 485 #ifdef MAC 486 mac_socket_create_mbuf(so, m); 487 #endif 488 /* Send packet to input processing via netisr */ 489 switch (ip->ip_v) { 490 case IPVERSION: 491 netisr_queue_src(NETISR_IP, (uintptr_t)so, m); 492 break; 493 #ifdef INET6 494 case IPV6_VERSION >> 4: 495 netisr_queue_src(NETISR_IPV6, (uintptr_t)so, m); 496 break; 497 #endif 498 default: 499 error = EINVAL; 500 goto cantsend; 501 } 502 } 503 504 return (error); 505 506 cantsend: 507 m_freem(m); 508 return (error); 509 } 510 511 static int 512 div_attach(struct socket *so, int proto, struct thread *td) 513 { 514 struct inpcb *inp; 515 int error; 516 517 inp = sotoinpcb(so); 518 KASSERT(inp == NULL, ("div_attach: inp != NULL")); 519 if (td != NULL) { 520 error = priv_check(td, PRIV_NETINET_DIVERT); 521 if (error) 522 return (error); 523 } 524 error = soreserve(so, div_sendspace, div_recvspace); 525 if (error) 526 return error; 527 INP_INFO_WLOCK(&V_divcbinfo); 528 error = in_pcballoc(so, &V_divcbinfo); 529 if (error) { 530 INP_INFO_WUNLOCK(&V_divcbinfo); 531 return error; 532 } 533 inp = (struct inpcb *)so->so_pcb; 534 INP_INFO_WUNLOCK(&V_divcbinfo); 535 inp->inp_ip_p = proto; 536 inp->inp_vflag |= INP_IPV4; 537 inp->inp_flags |= INP_HDRINCL; 538 INP_WUNLOCK(inp); 539 return 0; 540 } 541 542 static void 543 div_detach(struct socket *so) 544 { 545 struct inpcb *inp; 546 547 inp = sotoinpcb(so); 548 KASSERT(inp != NULL, ("div_detach: inp == NULL")); 549 INP_INFO_WLOCK(&V_divcbinfo); 550 INP_WLOCK(inp); 551 in_pcbdetach(inp); 552 in_pcbfree(inp); 553 INP_INFO_WUNLOCK(&V_divcbinfo); 554 } 555 556 static int 557 div_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 558 { 559 struct inpcb *inp; 560 int error; 561 562 inp = sotoinpcb(so); 563 KASSERT(inp != NULL, ("div_bind: inp == NULL")); 564 /* in_pcbbind assumes that nam is a sockaddr_in 565 * and in_pcbbind requires a valid address. Since divert 566 * sockets don't we need to make sure the address is 567 * filled in properly. 568 * XXX -- divert should not be abusing in_pcbind 569 * and should probably have its own family. 570 */ 571 if (nam->sa_family != AF_INET) 572 return EAFNOSUPPORT; 573 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY; 574 INP_INFO_WLOCK(&V_divcbinfo); 575 INP_WLOCK(inp); 576 INP_HASH_WLOCK(&V_divcbinfo); 577 error = in_pcbbind(inp, nam, td->td_ucred); 578 INP_HASH_WUNLOCK(&V_divcbinfo); 579 INP_WUNLOCK(inp); 580 INP_INFO_WUNLOCK(&V_divcbinfo); 581 return error; 582 } 583 584 static int 585 div_shutdown(struct socket *so) 586 { 587 struct inpcb *inp; 588 589 inp = sotoinpcb(so); 590 KASSERT(inp != NULL, ("div_shutdown: inp == NULL")); 591 INP_WLOCK(inp); 592 socantsendmore(so); 593 INP_WUNLOCK(inp); 594 return 0; 595 } 596 597 static int 598 div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, 599 struct mbuf *control, struct thread *td) 600 { 601 602 /* Packet must have a header (but that's about it) */ 603 if (m->m_len < sizeof (struct ip) && 604 (m = m_pullup(m, sizeof (struct ip))) == 0) { 605 KMOD_IPSTAT_INC(ips_toosmall); 606 m_freem(m); 607 return EINVAL; 608 } 609 610 /* Send packet */ 611 return div_output(so, m, (struct sockaddr_in *)nam, control); 612 } 613 614 static void 615 div_ctlinput(int cmd, struct sockaddr *sa, void *vip) 616 { 617 struct in_addr faddr; 618 619 faddr = ((struct sockaddr_in *)sa)->sin_addr; 620 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 621 return; 622 if (PRC_IS_REDIRECT(cmd)) 623 return; 624 } 625 626 static int 627 div_pcblist(SYSCTL_HANDLER_ARGS) 628 { 629 int error, i, n; 630 struct inpcb *inp, **inp_list; 631 inp_gen_t gencnt; 632 struct xinpgen xig; 633 634 /* 635 * The process of preparing the TCB list is too time-consuming and 636 * resource-intensive to repeat twice on every request. 637 */ 638 if (req->oldptr == 0) { 639 n = V_divcbinfo.ipi_count; 640 n += imax(n / 8, 10); 641 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb); 642 return 0; 643 } 644 645 if (req->newptr != 0) 646 return EPERM; 647 648 /* 649 * OK, now we're committed to doing something. 650 */ 651 INP_INFO_RLOCK(&V_divcbinfo); 652 gencnt = V_divcbinfo.ipi_gencnt; 653 n = V_divcbinfo.ipi_count; 654 INP_INFO_RUNLOCK(&V_divcbinfo); 655 656 error = sysctl_wire_old_buffer(req, 657 2 * sizeof(xig) + n*sizeof(struct xinpcb)); 658 if (error != 0) 659 return (error); 660 661 xig.xig_len = sizeof xig; 662 xig.xig_count = n; 663 xig.xig_gen = gencnt; 664 xig.xig_sogen = so_gencnt; 665 error = SYSCTL_OUT(req, &xig, sizeof xig); 666 if (error) 667 return error; 668 669 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 670 if (inp_list == 0) 671 return ENOMEM; 672 673 INP_INFO_RLOCK(&V_divcbinfo); 674 for (inp = LIST_FIRST(V_divcbinfo.ipi_listhead), i = 0; inp && i < n; 675 inp = LIST_NEXT(inp, inp_list)) { 676 INP_WLOCK(inp); 677 if (inp->inp_gencnt <= gencnt && 678 cr_canseeinpcb(req->td->td_ucred, inp) == 0) { 679 in_pcbref(inp); 680 inp_list[i++] = inp; 681 } 682 INP_WUNLOCK(inp); 683 } 684 INP_INFO_RUNLOCK(&V_divcbinfo); 685 n = i; 686 687 error = 0; 688 for (i = 0; i < n; i++) { 689 inp = inp_list[i]; 690 INP_RLOCK(inp); 691 if (inp->inp_gencnt <= gencnt) { 692 struct xinpcb xi; 693 bzero(&xi, sizeof(xi)); 694 xi.xi_len = sizeof xi; 695 /* XXX should avoid extra copy */ 696 bcopy(inp, &xi.xi_inp, sizeof *inp); 697 if (inp->inp_socket) 698 sotoxsocket(inp->inp_socket, &xi.xi_socket); 699 INP_RUNLOCK(inp); 700 error = SYSCTL_OUT(req, &xi, sizeof xi); 701 } else 702 INP_RUNLOCK(inp); 703 } 704 INP_INFO_WLOCK(&V_divcbinfo); 705 for (i = 0; i < n; i++) { 706 inp = inp_list[i]; 707 INP_RLOCK(inp); 708 if (!in_pcbrele_rlocked(inp)) 709 INP_RUNLOCK(inp); 710 } 711 INP_INFO_WUNLOCK(&V_divcbinfo); 712 713 if (!error) { 714 /* 715 * Give the user an updated idea of our state. 716 * If the generation differs from what we told 717 * her before, she knows that something happened 718 * while we were processing this request, and it 719 * might be necessary to retry. 720 */ 721 INP_INFO_RLOCK(&V_divcbinfo); 722 xig.xig_gen = V_divcbinfo.ipi_gencnt; 723 xig.xig_sogen = so_gencnt; 724 xig.xig_count = V_divcbinfo.ipi_count; 725 INP_INFO_RUNLOCK(&V_divcbinfo); 726 error = SYSCTL_OUT(req, &xig, sizeof xig); 727 } 728 free(inp_list, M_TEMP); 729 return error; 730 } 731 732 #ifdef SYSCTL_NODE 733 static SYSCTL_NODE(_net_inet, IPPROTO_DIVERT, divert, CTLFLAG_RW, 0, 734 "IPDIVERT"); 735 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLTYPE_OPAQUE | CTLFLAG_RD, 736 NULL, 0, div_pcblist, "S,xinpcb", "List of active divert sockets"); 737 #endif 738 739 struct pr_usrreqs div_usrreqs = { 740 .pru_attach = div_attach, 741 .pru_bind = div_bind, 742 .pru_control = in_control, 743 .pru_detach = div_detach, 744 .pru_peeraddr = in_getpeeraddr, 745 .pru_send = div_send, 746 .pru_shutdown = div_shutdown, 747 .pru_sockaddr = in_getsockaddr, 748 .pru_sosetlabel = in_pcbsosetlabel 749 }; 750 751 struct protosw div_protosw = { 752 .pr_type = SOCK_RAW, 753 .pr_protocol = IPPROTO_DIVERT, 754 .pr_flags = PR_ATOMIC|PR_ADDR, 755 .pr_input = div_input, 756 .pr_ctlinput = div_ctlinput, 757 .pr_ctloutput = ip_ctloutput, 758 .pr_init = div_init, 759 #ifdef VIMAGE 760 .pr_destroy = div_destroy, 761 #endif 762 .pr_usrreqs = &div_usrreqs 763 }; 764 765 static int 766 div_modevent(module_t mod, int type, void *unused) 767 { 768 int err = 0; 769 #ifndef VIMAGE 770 int n; 771 #endif 772 773 switch (type) { 774 case MOD_LOAD: 775 /* 776 * Protocol will be initialized by pf_proto_register(). 777 * We don't have to register ip_protox because we are not 778 * a true IP protocol that goes over the wire. 779 */ 780 err = pf_proto_register(PF_INET, &div_protosw); 781 if (err != 0) 782 return (err); 783 ip_divert_ptr = divert_packet; 784 ip_divert_event_tag = EVENTHANDLER_REGISTER(maxsockets_change, 785 div_zone_change, NULL, EVENTHANDLER_PRI_ANY); 786 break; 787 case MOD_QUIESCE: 788 /* 789 * IPDIVERT may normally not be unloaded because of the 790 * potential race conditions. Tell kldunload we can't be 791 * unloaded unless the unload is forced. 792 */ 793 err = EPERM; 794 break; 795 case MOD_UNLOAD: 796 #ifdef VIMAGE 797 err = EPERM; 798 break; 799 #else 800 /* 801 * Forced unload. 802 * 803 * Module ipdivert can only be unloaded if no sockets are 804 * connected. Maybe this can be changed later to forcefully 805 * disconnect any open sockets. 806 * 807 * XXXRW: Note that there is a slight race here, as a new 808 * socket open request could be spinning on the lock and then 809 * we destroy the lock. 810 */ 811 INP_INFO_WLOCK(&V_divcbinfo); 812 n = V_divcbinfo.ipi_count; 813 if (n != 0) { 814 err = EBUSY; 815 INP_INFO_WUNLOCK(&V_divcbinfo); 816 break; 817 } 818 ip_divert_ptr = NULL; 819 err = pf_proto_unregister(PF_INET, IPPROTO_DIVERT, SOCK_RAW); 820 INP_INFO_WUNLOCK(&V_divcbinfo); 821 div_destroy(); 822 EVENTHANDLER_DEREGISTER(maxsockets_change, ip_divert_event_tag); 823 break; 824 #endif /* !VIMAGE */ 825 default: 826 err = EOPNOTSUPP; 827 break; 828 } 829 return err; 830 } 831 832 static moduledata_t ipdivertmod = { 833 "ipdivert", 834 div_modevent, 835 0 836 }; 837 838 DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); 839 MODULE_DEPEND(ipdivert, ipfw, 3, 3, 3); 840 MODULE_VERSION(ipdivert, 1); 841