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