ip_divert.c revision 204810
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: head/sys/netinet/ip_divert.c 204810 2010-03-06 22:04:45Z rwatson $"); 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. */ 108static VNET_DEFINE(struct inpcbhead, divcb); 109static VNET_DEFINE(struct inpcbinfo, divcbinfo); 110 111#define V_divcb VNET(divcb) 112#define V_divcbinfo VNET(divcbinfo) 113 114static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */ 115static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */ 116 117static eventhandler_tag ip_divert_event_tag; 118 119/* 120 * Initialize divert connection block queue. 121 */ 122static void 123div_zone_change(void *tag) 124{ 125 126 uma_zone_set_max(V_divcbinfo.ipi_zone, maxsockets); 127} 128 129static int 130div_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 138static void 139div_inpcb_fini(void *mem, int size) 140{ 141 struct inpcb *inp = mem; 142 143 INP_LOCK_DESTROY(inp); 144} 145 146static void 147div_init(void) 148{ 149 150 INP_INFO_LOCK_INIT(&V_divcbinfo, "div"); 151 LIST_INIT(&V_divcb); 152 V_divcbinfo.ipi_listhead = &V_divcb; 153#ifdef VIMAGE 154 V_divcbinfo.ipi_vnet = curvnet; 155#endif 156 /* 157 * XXX We don't use the hash list for divert IP, but it's easier 158 * to allocate a one entry hash list than it is to check all 159 * over the place for hashbase == NULL. 160 */ 161 V_divcbinfo.ipi_hashbase = hashinit(1, M_PCB, &V_divcbinfo.ipi_hashmask); 162 V_divcbinfo.ipi_porthashbase = hashinit(1, M_PCB, 163 &V_divcbinfo.ipi_porthashmask); 164 V_divcbinfo.ipi_zone = uma_zcreate("divcb", sizeof(struct inpcb), 165 NULL, NULL, div_inpcb_init, div_inpcb_fini, UMA_ALIGN_PTR, 166 UMA_ZONE_NOFREE); 167 uma_zone_set_max(V_divcbinfo.ipi_zone, maxsockets); 168} 169 170static void 171div_destroy(void) 172{ 173 174 INP_INFO_LOCK_DESTROY(&V_divcbinfo); 175 uma_zdestroy(V_divcbinfo.ipi_zone); 176 hashdestroy(V_divcbinfo.ipi_hashbase, M_PCB, V_divcbinfo.ipi_hashmask); 177 hashdestroy(V_divcbinfo.ipi_porthashbase, M_PCB, 178 V_divcbinfo.ipi_porthashmask); 179} 180 181/* 182 * IPPROTO_DIVERT is not in the real IP protocol number space; this 183 * function should never be called. Just in case, drop any packets. 184 */ 185static void 186div_input(struct mbuf *m, int off) 187{ 188 189 KMOD_IPSTAT_INC(ips_noproto); 190 m_freem(m); 191} 192 193/* 194 * Divert a packet by passing it up to the divert socket at port 'port'. 195 * 196 * Setup generic address and protocol structures for div_input routine, 197 * then pass them along with mbuf chain. 198 */ 199static void 200divert_packet(struct mbuf *m, int incoming) 201{ 202 struct ip *ip; 203 struct inpcb *inp; 204 struct socket *sa; 205 u_int16_t nport; 206 struct sockaddr_in divsrc; 207 struct m_tag *mtag; 208 209 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL); 210 if (mtag == NULL) { 211 m_freem(m); 212 return; 213 } 214 /* Assure header */ 215 if (m->m_len < sizeof(struct ip) && 216 (m = m_pullup(m, sizeof(struct ip))) == 0) 217 return; 218 ip = mtod(m, struct ip *); 219 220 /* Delayed checksums are currently not compatible with divert. */ 221 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 222 ip->ip_len = ntohs(ip->ip_len); 223 in_delayed_cksum(m); 224 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 225 ip->ip_len = htons(ip->ip_len); 226 } 227#ifdef SCTP 228 if (m->m_pkthdr.csum_flags & CSUM_SCTP) { 229 ip->ip_len = ntohs(ip->ip_len); 230 sctp_delayed_cksum(m); 231 m->m_pkthdr.csum_flags &= ~CSUM_SCTP; 232 ip->ip_len = htons(ip->ip_len); 233 } 234#endif 235 bzero(&divsrc, sizeof(divsrc)); 236 divsrc.sin_len = sizeof(divsrc); 237 divsrc.sin_family = AF_INET; 238 /* record matching rule, in host format */ 239 divsrc.sin_port = ((struct ipfw_rule_ref *)(mtag+1))->rulenum; 240 /* 241 * Record receive interface address, if any. 242 * But only for incoming packets. 243 */ 244 if (incoming) { 245 struct ifaddr *ifa; 246 struct ifnet *ifp; 247 248 /* Sanity check */ 249 M_ASSERTPKTHDR(m); 250 251 /* Find IP address for receive interface */ 252 ifp = m->m_pkthdr.rcvif; 253 if_addr_rlock(ifp); 254 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 255 if (ifa->ifa_addr->sa_family != AF_INET) 256 continue; 257 divsrc.sin_addr = 258 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr; 259 break; 260 } 261 if_addr_runlock(ifp); 262 } 263 /* 264 * Record the incoming interface name whenever we have one. 265 */ 266 if (m->m_pkthdr.rcvif) { 267 /* 268 * Hide the actual interface name in there in the 269 * sin_zero array. XXX This needs to be moved to a 270 * different sockaddr type for divert, e.g. 271 * sockaddr_div with multiple fields like 272 * sockaddr_dl. Presently we have only 7 bytes 273 * but that will do for now as most interfaces 274 * are 4 or less + 2 or less bytes for unit. 275 * There is probably a faster way of doing this, 276 * possibly taking it from the sockaddr_dl on the iface. 277 * This solves the problem of a P2P link and a LAN interface 278 * having the same address, which can result in the wrong 279 * interface being assigned to the packet when fed back 280 * into the divert socket. Theoretically if the daemon saves 281 * and re-uses the sockaddr_in as suggested in the man pages, 282 * this iface name will come along for the ride. 283 * (see div_output for the other half of this.) 284 */ 285 strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname, 286 sizeof(divsrc.sin_zero)); 287 } 288 289 /* Put packet on socket queue, if any */ 290 sa = NULL; 291 nport = htons((u_int16_t)(((struct ipfw_rule_ref *)(mtag+1))->info)); 292 INP_INFO_RLOCK(&V_divcbinfo); 293 LIST_FOREACH(inp, &V_divcb, inp_list) { 294 /* XXX why does only one socket match? */ 295 if (inp->inp_lport == nport) { 296 INP_RLOCK(inp); 297 sa = inp->inp_socket; 298 SOCKBUF_LOCK(&sa->so_rcv); 299 if (sbappendaddr_locked(&sa->so_rcv, 300 (struct sockaddr *)&divsrc, m, 301 (struct mbuf *)0) == 0) { 302 SOCKBUF_UNLOCK(&sa->so_rcv); 303 sa = NULL; /* force mbuf reclaim below */ 304 } else 305 sorwakeup_locked(sa); 306 INP_RUNLOCK(inp); 307 break; 308 } 309 } 310 INP_INFO_RUNLOCK(&V_divcbinfo); 311 if (sa == NULL) { 312 m_freem(m); 313 KMOD_IPSTAT_INC(ips_noproto); 314 KMOD_IPSTAT_DEC(ips_delivered); 315 } 316} 317 318/* 319 * Deliver packet back into the IP processing machinery. 320 * 321 * If no address specified, or address is 0.0.0.0, send to ip_output(); 322 * otherwise, send to ip_input() and mark as having been received on 323 * the interface with that address. 324 */ 325static int 326div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin, 327 struct mbuf *control) 328{ 329 struct m_tag *mtag; 330 struct ipfw_rule_ref *dt; 331 int error = 0; 332 struct mbuf *options; 333 334 /* 335 * An mbuf may hasn't come from userland, but we pretend 336 * that it has. 337 */ 338 m->m_pkthdr.rcvif = NULL; 339 m->m_nextpkt = NULL; 340 M_SETFIB(m, so->so_fibnum); 341 342 if (control) 343 m_freem(control); /* XXX */ 344 345 mtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL); 346 if (mtag == NULL) { 347 /* this should be normal */ 348 mtag = m_tag_alloc(MTAG_IPFW_RULE, 0, 349 sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO); 350 if (mtag == NULL) { 351 error = ENOBUFS; 352 goto cantsend; 353 } 354 m_tag_prepend(m, mtag); 355 } 356 dt = (struct ipfw_rule_ref *)(mtag+1); 357 358 /* Loopback avoidance and state recovery */ 359 if (sin) { 360 int i; 361 362 /* set the starting point. We provide a non-zero slot, 363 * but a non_matching chain_id to skip that info and use 364 * the rulenum/rule_id. 365 */ 366 dt->slot = 1; /* dummy, chain_id is invalid */ 367 dt->chain_id = 0; 368 dt->rulenum = sin->sin_port+1; /* host format ? */ 369 dt->rule_id = 0; 370 /* 371 * Find receive interface with the given name, stuffed 372 * (if it exists) in the sin_zero[] field. 373 * The name is user supplied data so don't trust its size 374 * or that it is zero terminated. 375 */ 376 for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++) 377 ; 378 if ( i > 0 && i < sizeof(sin->sin_zero)) 379 m->m_pkthdr.rcvif = ifunit(sin->sin_zero); 380 } 381 382 /* Reinject packet into the system as incoming or outgoing */ 383 if (!sin || sin->sin_addr.s_addr == 0) { 384 struct ip *const ip = mtod(m, struct ip *); 385 struct inpcb *inp; 386 387 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_OUT; 388 inp = sotoinpcb(so); 389 INP_RLOCK(inp); 390 /* 391 * Don't allow both user specified and setsockopt options, 392 * and don't allow packet length sizes that will crash 393 */ 394 if (((ip->ip_hl != (sizeof (*ip) >> 2)) && inp->inp_options) || 395 ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) { 396 error = EINVAL; 397 INP_RUNLOCK(inp); 398 m_freem(m); 399 } else { 400 /* Convert fields to host order for ip_output() */ 401 ip->ip_len = ntohs(ip->ip_len); 402 ip->ip_off = ntohs(ip->ip_off); 403 404 /* Send packet to output processing */ 405 KMOD_IPSTAT_INC(ips_rawout); /* XXX */ 406 407#ifdef MAC 408 mac_inpcb_create_mbuf(inp, m); 409#endif 410 /* 411 * Get ready to inject the packet into ip_output(). 412 * Just in case socket options were specified on the 413 * divert socket, we duplicate them. This is done 414 * to avoid having to hold the PCB locks over the call 415 * to ip_output(), as doing this results in a number of 416 * lock ordering complexities. 417 * 418 * Note that we set the multicast options argument for 419 * ip_output() to NULL since it should be invariant that 420 * they are not present. 421 */ 422 KASSERT(inp->inp_moptions == NULL, 423 ("multicast options set on a divert socket")); 424 options = NULL; 425 /* 426 * XXXCSJP: It is unclear to me whether or not it makes 427 * sense for divert sockets to have options. However, 428 * for now we will duplicate them with the INP locks 429 * held so we can use them in ip_output() without 430 * requring a reference to the pcb. 431 */ 432 if (inp->inp_options != NULL) { 433 options = m_dup(inp->inp_options, M_DONTWAIT); 434 if (options == NULL) 435 error = ENOBUFS; 436 } 437 INP_RUNLOCK(inp); 438 if (error == ENOBUFS) { 439 m_freem(m); 440 return (error); 441 } 442 error = ip_output(m, options, NULL, 443 ((so->so_options & SO_DONTROUTE) ? 444 IP_ROUTETOIF : 0) | IP_ALLOWBROADCAST | 445 IP_RAWOUTPUT, NULL, NULL); 446 if (options != NULL) 447 m_freem(options); 448 } 449 } else { 450 dt->info |= IPFW_IS_DIVERT | IPFW_INFO_IN; 451 if (m->m_pkthdr.rcvif == NULL) { 452 /* 453 * No luck with the name, check by IP address. 454 * Clear the port and the ifname to make sure 455 * there are no distractions for ifa_ifwithaddr. 456 */ 457 struct ifaddr *ifa; 458 459 bzero(sin->sin_zero, sizeof(sin->sin_zero)); 460 sin->sin_port = 0; 461 ifa = ifa_ifwithaddr((struct sockaddr *) sin); 462 if (ifa == NULL) { 463 error = EADDRNOTAVAIL; 464 goto cantsend; 465 } 466 m->m_pkthdr.rcvif = ifa->ifa_ifp; 467 ifa_free(ifa); 468 } 469#ifdef MAC 470 mac_socket_create_mbuf(so, m); 471#endif 472 /* Send packet to input processing via netisr */ 473 netisr_queue_src(NETISR_IP, (uintptr_t)so, m); 474 } 475 476 return error; 477 478cantsend: 479 m_freem(m); 480 return error; 481} 482 483static int 484div_attach(struct socket *so, int proto, struct thread *td) 485{ 486 struct inpcb *inp; 487 int error; 488 489 inp = sotoinpcb(so); 490 KASSERT(inp == NULL, ("div_attach: inp != NULL")); 491 if (td != NULL) { 492 error = priv_check(td, PRIV_NETINET_DIVERT); 493 if (error) 494 return (error); 495 } 496 error = soreserve(so, div_sendspace, div_recvspace); 497 if (error) 498 return error; 499 INP_INFO_WLOCK(&V_divcbinfo); 500 error = in_pcballoc(so, &V_divcbinfo); 501 if (error) { 502 INP_INFO_WUNLOCK(&V_divcbinfo); 503 return error; 504 } 505 inp = (struct inpcb *)so->so_pcb; 506 INP_INFO_WUNLOCK(&V_divcbinfo); 507 inp->inp_ip_p = proto; 508 inp->inp_vflag |= INP_IPV4; 509 inp->inp_flags |= INP_HDRINCL; 510 INP_WUNLOCK(inp); 511 return 0; 512} 513 514static void 515div_detach(struct socket *so) 516{ 517 struct inpcb *inp; 518 519 inp = sotoinpcb(so); 520 KASSERT(inp != NULL, ("div_detach: inp == NULL")); 521 INP_INFO_WLOCK(&V_divcbinfo); 522 INP_WLOCK(inp); 523 in_pcbdetach(inp); 524 in_pcbfree(inp); 525 INP_INFO_WUNLOCK(&V_divcbinfo); 526} 527 528static int 529div_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 530{ 531 struct inpcb *inp; 532 int error; 533 534 inp = sotoinpcb(so); 535 KASSERT(inp != NULL, ("div_bind: inp == NULL")); 536 /* in_pcbbind assumes that nam is a sockaddr_in 537 * and in_pcbbind requires a valid address. Since divert 538 * sockets don't we need to make sure the address is 539 * filled in properly. 540 * XXX -- divert should not be abusing in_pcbind 541 * and should probably have its own family. 542 */ 543 if (nam->sa_family != AF_INET) 544 return EAFNOSUPPORT; 545 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY; 546 INP_INFO_WLOCK(&V_divcbinfo); 547 INP_WLOCK(inp); 548 error = in_pcbbind(inp, nam, td->td_ucred); 549 INP_WUNLOCK(inp); 550 INP_INFO_WUNLOCK(&V_divcbinfo); 551 return error; 552} 553 554static int 555div_shutdown(struct socket *so) 556{ 557 struct inpcb *inp; 558 559 inp = sotoinpcb(so); 560 KASSERT(inp != NULL, ("div_shutdown: inp == NULL")); 561 INP_WLOCK(inp); 562 socantsendmore(so); 563 INP_WUNLOCK(inp); 564 return 0; 565} 566 567static int 568div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, 569 struct mbuf *control, struct thread *td) 570{ 571 572 /* Packet must have a header (but that's about it) */ 573 if (m->m_len < sizeof (struct ip) && 574 (m = m_pullup(m, sizeof (struct ip))) == 0) { 575 KMOD_IPSTAT_INC(ips_toosmall); 576 m_freem(m); 577 return EINVAL; 578 } 579 580 /* Send packet */ 581 return div_output(so, m, (struct sockaddr_in *)nam, control); 582} 583 584static void 585div_ctlinput(int cmd, struct sockaddr *sa, void *vip) 586{ 587 struct in_addr faddr; 588 589 faddr = ((struct sockaddr_in *)sa)->sin_addr; 590 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 591 return; 592 if (PRC_IS_REDIRECT(cmd)) 593 return; 594} 595 596static int 597div_pcblist(SYSCTL_HANDLER_ARGS) 598{ 599 int error, i, n; 600 struct inpcb *inp, **inp_list; 601 inp_gen_t gencnt; 602 struct xinpgen xig; 603 604 /* 605 * The process of preparing the TCB list is too time-consuming and 606 * resource-intensive to repeat twice on every request. 607 */ 608 if (req->oldptr == 0) { 609 n = V_divcbinfo.ipi_count; 610 req->oldidx = 2 * (sizeof xig) 611 + (n + n/8) * sizeof(struct xinpcb); 612 return 0; 613 } 614 615 if (req->newptr != 0) 616 return EPERM; 617 618 /* 619 * OK, now we're committed to doing something. 620 */ 621 INP_INFO_RLOCK(&V_divcbinfo); 622 gencnt = V_divcbinfo.ipi_gencnt; 623 n = V_divcbinfo.ipi_count; 624 INP_INFO_RUNLOCK(&V_divcbinfo); 625 626 error = sysctl_wire_old_buffer(req, 627 2 * sizeof(xig) + n*sizeof(struct xinpcb)); 628 if (error != 0) 629 return (error); 630 631 xig.xig_len = sizeof xig; 632 xig.xig_count = n; 633 xig.xig_gen = gencnt; 634 xig.xig_sogen = so_gencnt; 635 error = SYSCTL_OUT(req, &xig, sizeof xig); 636 if (error) 637 return error; 638 639 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 640 if (inp_list == 0) 641 return ENOMEM; 642 643 INP_INFO_RLOCK(&V_divcbinfo); 644 for (inp = LIST_FIRST(V_divcbinfo.ipi_listhead), i = 0; inp && i < n; 645 inp = LIST_NEXT(inp, inp_list)) { 646 INP_RLOCK(inp); 647 if (inp->inp_gencnt <= gencnt && 648 cr_canseeinpcb(req->td->td_ucred, inp) == 0) 649 inp_list[i++] = inp; 650 INP_RUNLOCK(inp); 651 } 652 INP_INFO_RUNLOCK(&V_divcbinfo); 653 n = i; 654 655 error = 0; 656 for (i = 0; i < n; i++) { 657 inp = inp_list[i]; 658 INP_RLOCK(inp); 659 if (inp->inp_gencnt <= gencnt) { 660 struct xinpcb xi; 661 bzero(&xi, sizeof(xi)); 662 xi.xi_len = sizeof xi; 663 /* XXX should avoid extra copy */ 664 bcopy(inp, &xi.xi_inp, sizeof *inp); 665 if (inp->inp_socket) 666 sotoxsocket(inp->inp_socket, &xi.xi_socket); 667 INP_RUNLOCK(inp); 668 error = SYSCTL_OUT(req, &xi, sizeof xi); 669 } else 670 INP_RUNLOCK(inp); 671 } 672 if (!error) { 673 /* 674 * Give the user an updated idea of our state. 675 * If the generation differs from what we told 676 * her before, she knows that something happened 677 * while we were processing this request, and it 678 * might be necessary to retry. 679 */ 680 INP_INFO_RLOCK(&V_divcbinfo); 681 xig.xig_gen = V_divcbinfo.ipi_gencnt; 682 xig.xig_sogen = so_gencnt; 683 xig.xig_count = V_divcbinfo.ipi_count; 684 INP_INFO_RUNLOCK(&V_divcbinfo); 685 error = SYSCTL_OUT(req, &xig, sizeof xig); 686 } 687 free(inp_list, M_TEMP); 688 return error; 689} 690 691#ifdef SYSCTL_NODE 692SYSCTL_NODE(_net_inet, IPPROTO_DIVERT, divert, CTLFLAG_RW, 0, "IPDIVERT"); 693SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLFLAG_RD, 0, 0, 694 div_pcblist, "S,xinpcb", "List of active divert sockets"); 695#endif 696 697struct pr_usrreqs div_usrreqs = { 698 .pru_attach = div_attach, 699 .pru_bind = div_bind, 700 .pru_control = in_control, 701 .pru_detach = div_detach, 702 .pru_peeraddr = in_getpeeraddr, 703 .pru_send = div_send, 704 .pru_shutdown = div_shutdown, 705 .pru_sockaddr = in_getsockaddr, 706 .pru_sosetlabel = in_pcbsosetlabel 707}; 708 709struct protosw div_protosw = { 710 .pr_type = SOCK_RAW, 711 .pr_protocol = IPPROTO_DIVERT, 712 .pr_flags = PR_ATOMIC|PR_ADDR, 713 .pr_input = div_input, 714 .pr_ctlinput = div_ctlinput, 715 .pr_ctloutput = ip_ctloutput, 716 .pr_init = div_init, 717#ifdef VIMAGE 718 .pr_destroy = div_destroy, 719#endif 720 .pr_usrreqs = &div_usrreqs 721}; 722 723static int 724div_modevent(module_t mod, int type, void *unused) 725{ 726 int err = 0; 727#ifndef VIMAGE 728 int n; 729#endif 730 731 switch (type) { 732 case MOD_LOAD: 733 /* 734 * Protocol will be initialized by pf_proto_register(). 735 * We don't have to register ip_protox because we are not 736 * a true IP protocol that goes over the wire. 737 */ 738 err = pf_proto_register(PF_INET, &div_protosw); 739 if (err != 0) 740 return (err); 741 ip_divert_ptr = divert_packet; 742 ip_divert_event_tag = EVENTHANDLER_REGISTER(maxsockets_change, 743 div_zone_change, NULL, EVENTHANDLER_PRI_ANY); 744 break; 745 case MOD_QUIESCE: 746 /* 747 * IPDIVERT may normally not be unloaded because of the 748 * potential race conditions. Tell kldunload we can't be 749 * unloaded unless the unload is forced. 750 */ 751 err = EPERM; 752 break; 753 case MOD_UNLOAD: 754#ifdef VIMAGE 755 err = EPERM; 756 break; 757#else 758 /* 759 * Forced unload. 760 * 761 * Module ipdivert can only be unloaded if no sockets are 762 * connected. Maybe this can be changed later to forcefully 763 * disconnect any open sockets. 764 * 765 * XXXRW: Note that there is a slight race here, as a new 766 * socket open request could be spinning on the lock and then 767 * we destroy the lock. 768 */ 769 INP_INFO_WLOCK(&V_divcbinfo); 770 n = V_divcbinfo.ipi_count; 771 if (n != 0) { 772 err = EBUSY; 773 INP_INFO_WUNLOCK(&V_divcbinfo); 774 break; 775 } 776 ip_divert_ptr = NULL; 777 err = pf_proto_unregister(PF_INET, IPPROTO_DIVERT, SOCK_RAW); 778 INP_INFO_WUNLOCK(&V_divcbinfo); 779 div_destroy(); 780 EVENTHANDLER_DEREGISTER(maxsockets_change, ip_divert_event_tag); 781 break; 782#endif /* !VIMAGE */ 783 default: 784 err = EOPNOTSUPP; 785 break; 786 } 787 return err; 788} 789 790static moduledata_t ipdivertmod = { 791 "ipdivert", 792 div_modevent, 793 0 794}; 795 796DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); 797MODULE_DEPEND(ipdivert, ipfw, 2, 2, 2); 798MODULE_VERSION(ipdivert, 1); 799