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_ipfw.h" 36 #include "opt_mac.h" 37 #ifndef INET 38 #error "IPDIVERT requires INET." 39 #endif 40 #ifndef IPFIREWALL 41 #error "IPDIVERT requires IPFIREWALL" 42 #endif 43 #endif 44 45 #include <sys/param.h> 46 #include <sys/kernel.h> 47 #include <sys/lock.h> 48 #include <sys/malloc.h> 49 #include <sys/mbuf.h> 50 #include <sys/module.h> 51 #include <sys/kernel.h> 52 #include <sys/priv.h> 53 #include <sys/proc.h> 54 #include <sys/protosw.h> 55 #include <sys/signalvar.h> 56 #include <sys/socket.h> 57 #include <sys/socketvar.h> 58 #include <sys/sx.h> 59 #include <sys/sysctl.h> 60 #include <sys/systm.h> 61 62 #include <vm/uma.h> 63 64 #include <net/if.h> 65 #include <net/netisr.h> 66 #include <net/route.h> 67 68 #include <netinet/in.h> 69 #include <netinet/in_pcb.h> 70 #include <netinet/in_systm.h> 71 #include <netinet/in_var.h> 72 #include <netinet/ip.h> 73 #include <netinet/ip_divert.h> 74 #include <netinet/ip_var.h> 75 #include <netinet/ip_fw.h> 76 77 #include <security/mac/mac_framework.h> 78 79 /* 80 * Divert sockets 81 */ 82 83 /* 84 * Allocate enough space to hold a full IP packet 85 */ 86 #define DIVSNDQ (65536 + 100) 87 #define DIVRCVQ (65536 + 100) 88 89 /* 90 * Divert sockets work in conjunction with ipfw, see the divert(4) 91 * manpage for features. 92 * Internally, packets selected by ipfw in ip_input() or ip_output(), 93 * and never diverted before, are passed to the input queue of the 94 * divert socket with a given 'divert_port' number (as specified in 95 * the matching ipfw rule), and they are tagged with a 16 bit cookie 96 * (representing the rule number of the matching ipfw rule), which 97 * is passed to process reading from the socket. 98 * 99 * Packets written to the divert socket are again tagged with a cookie 100 * (usually the same as above) and a destination address. 101 * If the destination address is INADDR_ANY then the packet is 102 * treated as outgoing and sent to ip_output(), otherwise it is 103 * treated as incoming and sent to ip_input(). 104 * In both cases, the packet is tagged with the cookie. 105 * 106 * On reinjection, processing in ip_input() and ip_output() 107 * will be exactly the same as for the original packet, except that 108 * ipfw processing will start at the rule number after the one 109 * written in the cookie (so, tagging a packet with a cookie of 0 110 * will cause it to be effectively considered as a standard packet). 111 */ 112 113 /* Internal variables. */ 114 static struct inpcbhead divcb; 115 static struct inpcbinfo divcbinfo; 116 117 static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */ 118 static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */ 119 120 /* 121 * Initialize divert connection block queue. 122 */ 123 static void 124 div_zone_change(void *tag) 125 { 126 127 uma_zone_set_max(divcbinfo.ipi_zone, maxsockets); 128 } 129 130 static int 131 div_inpcb_init(void *mem, int size, int flags) 132 { 133 struct inpcb *inp = mem; 134 135 INP_LOCK_INIT(inp, "inp", "divinp"); 136 return (0); 137 } 138 139 static void 140 div_inpcb_fini(void *mem, int size) 141 { 142 struct inpcb *inp = mem; 143 144 INP_LOCK_DESTROY(inp); 145 } 146 147 void 148 div_init(void) 149 { 150 151 INP_INFO_LOCK_INIT(&divcbinfo, "div"); 152 LIST_INIT(&divcb); 153 divcbinfo.ipi_listhead = &divcb; 154 /* 155 * XXX We don't use the hash list for divert IP, but it's easier 156 * to allocate a one entry hash list than it is to check all 157 * over the place for hashbase == NULL. 158 */ 159 divcbinfo.ipi_hashbase = hashinit(1, M_PCB, &divcbinfo.ipi_hashmask); 160 divcbinfo.ipi_porthashbase = hashinit(1, M_PCB, 161 &divcbinfo.ipi_porthashmask); 162 divcbinfo.ipi_zone = uma_zcreate("divcb", sizeof(struct inpcb), 163 NULL, NULL, div_inpcb_init, div_inpcb_fini, UMA_ALIGN_PTR, 164 UMA_ZONE_NOFREE); 165 uma_zone_set_max(divcbinfo.ipi_zone, maxsockets); 166 EVENTHANDLER_REGISTER(maxsockets_change, div_zone_change, 167 NULL, EVENTHANDLER_PRI_ANY); 168 } 169 170 /* 171 * IPPROTO_DIVERT is not in the real IP protocol number space; this 172 * function should never be called. Just in case, drop any packets. 173 */ 174 void 175 div_input(struct mbuf *m, int off) 176 { 177 ipstat.ips_noproto++; 178 m_freem(m); 179 } 180 181 /* 182 * Divert a packet by passing it up to the divert socket at port 'port'. 183 * 184 * Setup generic address and protocol structures for div_input routine, 185 * then pass them along with mbuf chain. 186 */ 187 static void 188 divert_packet(struct mbuf *m, int incoming) 189 { 190 struct ip *ip; 191 struct inpcb *inp; 192 struct socket *sa; 193 u_int16_t nport; 194 struct sockaddr_in divsrc; 195 struct m_tag *mtag; 196 197 mtag = m_tag_find(m, PACKET_TAG_DIVERT, NULL); 198 if (mtag == NULL) { 199 printf("%s: no divert tag\n", __func__); 200 m_freem(m); 201 return; 202 } 203 /* Assure header */ 204 if (m->m_len < sizeof(struct ip) && 205 (m = m_pullup(m, sizeof(struct ip))) == 0) 206 return; 207 ip = mtod(m, struct ip *); 208 209 /* Delayed checksums are currently not compatible with divert. */ 210 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 211 ip->ip_len = ntohs(ip->ip_len); 212 in_delayed_cksum(m); 213 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 214 ip->ip_len = htons(ip->ip_len); 215 } 216 217 /* 218 * Record receive interface address, if any. 219 * But only for incoming packets. 220 */ 221 bzero(&divsrc, sizeof(divsrc)); 222 divsrc.sin_len = sizeof(divsrc); 223 divsrc.sin_family = AF_INET; 224 divsrc.sin_port = divert_cookie(mtag); /* record matching rule */ 225 if (incoming) { 226 struct ifaddr *ifa; 227 228 /* Sanity check */ 229 M_ASSERTPKTHDR(m); 230 231 /* Find IP address for receive interface */ 232 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrhead, ifa_link) { 233 if (ifa->ifa_addr->sa_family != AF_INET) 234 continue; 235 divsrc.sin_addr = 236 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr; 237 break; 238 } 239 } 240 /* 241 * Record the incoming interface name whenever we have one. 242 */ 243 if (m->m_pkthdr.rcvif) { 244 /* 245 * Hide the actual interface name in there in the 246 * sin_zero array. XXX This needs to be moved to a 247 * different sockaddr type for divert, e.g. 248 * sockaddr_div with multiple fields like 249 * sockaddr_dl. Presently we have only 7 bytes 250 * but that will do for now as most interfaces 251 * are 4 or less + 2 or less bytes for unit. 252 * There is probably a faster way of doing this, 253 * possibly taking it from the sockaddr_dl on the iface. 254 * This solves the problem of a P2P link and a LAN interface 255 * having the same address, which can result in the wrong 256 * interface being assigned to the packet when fed back 257 * into the divert socket. Theoretically if the daemon saves 258 * and re-uses the sockaddr_in as suggested in the man pages, 259 * this iface name will come along for the ride. 260 * (see div_output for the other half of this.) 261 */ 262 strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname, 263 sizeof(divsrc.sin_zero)); 264 } 265 266 /* Put packet on socket queue, if any */ 267 sa = NULL; 268 nport = htons((u_int16_t)divert_info(mtag)); 269 INP_INFO_RLOCK(&divcbinfo); 270 LIST_FOREACH(inp, &divcb, inp_list) { 271 /* XXX why does only one socket match? */ 272 if (inp->inp_lport == nport) { 273 INP_RLOCK(inp); 274 sa = inp->inp_socket; 275 SOCKBUF_LOCK(&sa->so_rcv); 276 if (sbappendaddr_locked(&sa->so_rcv, 277 (struct sockaddr *)&divsrc, m, 278 (struct mbuf *)0) == 0) { 279 SOCKBUF_UNLOCK(&sa->so_rcv); 280 sa = NULL; /* force mbuf reclaim below */ 281 } else 282 sorwakeup_locked(sa); 283 INP_RUNLOCK(inp); 284 break; 285 } 286 } 287 INP_INFO_RUNLOCK(&divcbinfo); 288 if (sa == NULL) { 289 m_freem(m); 290 ipstat.ips_noproto++; 291 ipstat.ips_delivered--; 292 } 293 } 294 295 /* 296 * Deliver packet back into the IP processing machinery. 297 * 298 * If no address specified, or address is 0.0.0.0, send to ip_output(); 299 * otherwise, send to ip_input() and mark as having been received on 300 * the interface with that address. 301 */ 302 static int 303 div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin, 304 struct mbuf *control) 305 { 306 struct m_tag *mtag; 307 struct divert_tag *dt; 308 int error = 0; 309 struct mbuf *options; 310 311 /* 312 * An mbuf may hasn't come from userland, but we pretend 313 * that it has. 314 */ 315 m->m_pkthdr.rcvif = NULL; 316 m->m_nextpkt = NULL; 317 318 if (control) 319 m_freem(control); /* XXX */ 320 321 if ((mtag = m_tag_find(m, PACKET_TAG_DIVERT, NULL)) == NULL) { 322 mtag = m_tag_get(PACKET_TAG_DIVERT, sizeof(struct divert_tag), 323 M_NOWAIT | M_ZERO); 324 if (mtag == NULL) { 325 error = ENOBUFS; 326 goto cantsend; 327 } 328 dt = (struct divert_tag *)(mtag+1); 329 m_tag_prepend(m, mtag); 330 } else 331 dt = (struct divert_tag *)(mtag+1); 332 333 /* Loopback avoidance and state recovery */ 334 if (sin) { 335 int i; 336 337 dt->cookie = sin->sin_port; 338 /* 339 * Find receive interface with the given name, stuffed 340 * (if it exists) in the sin_zero[] field. 341 * The name is user supplied data so don't trust its size 342 * or that it is zero terminated. 343 */ 344 for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++) 345 ; 346 if ( i > 0 && i < sizeof(sin->sin_zero)) 347 m->m_pkthdr.rcvif = ifunit(sin->sin_zero); 348 } 349 350 /* Reinject packet into the system as incoming or outgoing */ 351 if (!sin || sin->sin_addr.s_addr == 0) { 352 struct ip *const ip = mtod(m, struct ip *); 353 struct inpcb *inp; 354 355 dt->info |= IP_FW_DIVERT_OUTPUT_FLAG; 356 INP_INFO_WLOCK(&divcbinfo); 357 inp = sotoinpcb(so); 358 INP_RLOCK(inp); 359 /* 360 * Don't allow both user specified and setsockopt options, 361 * and don't allow packet length sizes that will crash 362 */ 363 if (((ip->ip_hl != (sizeof (*ip) >> 2)) && inp->inp_options) || 364 ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) { 365 error = EINVAL; 366 INP_RUNLOCK(inp); 367 INP_INFO_WUNLOCK(&divcbinfo); 368 m_freem(m); 369 } else { 370 /* Convert fields to host order for ip_output() */ 371 ip->ip_len = ntohs(ip->ip_len); 372 ip->ip_off = ntohs(ip->ip_off); 373 374 /* Send packet to output processing */ 375 ipstat.ips_rawout++; /* XXX */ 376 377 #ifdef MAC 378 mac_inpcb_create_mbuf(inp, m); 379 #endif 380 /* 381 * Get ready to inject the packet into ip_output(). 382 * Just in case socket options were specified on the 383 * divert socket, we duplicate them. This is done 384 * to avoid having to hold the PCB locks over the call 385 * to ip_output(), as doing this results in a number of 386 * lock ordering complexities. 387 * 388 * Note that we set the multicast options argument for 389 * ip_output() to NULL since it should be invariant that 390 * they are not present. 391 */ 392 KASSERT(inp->inp_moptions == NULL, 393 ("multicast options set on a divert socket")); 394 options = NULL; 395 /* 396 * XXXCSJP: It is unclear to me whether or not it makes 397 * sense for divert sockets to have options. However, 398 * for now we will duplicate them with the INP locks 399 * held so we can use them in ip_output() without 400 * requring a reference to the pcb. 401 */ 402 if (inp->inp_options != NULL) { 403 options = m_dup(inp->inp_options, M_DONTWAIT); 404 if (options == NULL) 405 error = ENOBUFS; 406 } 407 INP_RUNLOCK(inp); 408 INP_INFO_WUNLOCK(&divcbinfo); 409 if (error == ENOBUFS) { 410 m_freem(m); 411 return (error); 412 } 413 error = ip_output(m, options, NULL, 414 ((so->so_options & SO_DONTROUTE) ? 415 IP_ROUTETOIF : 0) | IP_ALLOWBROADCAST | 416 IP_RAWOUTPUT, NULL, NULL); 417 if (options != NULL) 418 m_freem(options); 419 } 420 } else { 421 dt->info |= IP_FW_DIVERT_LOOPBACK_FLAG; 422 if (m->m_pkthdr.rcvif == NULL) { 423 /* 424 * No luck with the name, check by IP address. 425 * Clear the port and the ifname to make sure 426 * there are no distractions for ifa_ifwithaddr. 427 */ 428 struct ifaddr *ifa; 429 430 bzero(sin->sin_zero, sizeof(sin->sin_zero)); 431 sin->sin_port = 0; 432 ifa = ifa_ifwithaddr((struct sockaddr *) sin); 433 if (ifa == NULL) { 434 error = EADDRNOTAVAIL; 435 goto cantsend; 436 } 437 m->m_pkthdr.rcvif = ifa->ifa_ifp; 438 } 439 #ifdef MAC 440 SOCK_LOCK(so); 441 mac_socket_create_mbuf(so, m); 442 SOCK_UNLOCK(so); 443 #endif 444 /* Send packet to input processing via netisr */ 445 netisr_queue(NETISR_IP, m); 446 } 447 448 return error; 449 450 cantsend: 451 m_freem(m); 452 return error; 453 } 454 455 static int 456 div_attach(struct socket *so, int proto, struct thread *td) 457 { 458 struct inpcb *inp; 459 int error; 460 461 inp = sotoinpcb(so); 462 KASSERT(inp == NULL, ("div_attach: inp != NULL")); 463 if (td != NULL) { 464 error = priv_check(td, PRIV_NETINET_DIVERT); 465 if (error) 466 return (error); 467 } 468 error = soreserve(so, div_sendspace, div_recvspace); 469 if (error) 470 return error; 471 INP_INFO_WLOCK(&divcbinfo); 472 error = in_pcballoc(so, &divcbinfo); 473 if (error) { 474 INP_INFO_WUNLOCK(&divcbinfo); 475 return error; 476 } 477 inp = (struct inpcb *)so->so_pcb; 478 INP_INFO_WUNLOCK(&divcbinfo); 479 inp->inp_ip_p = proto; 480 inp->inp_vflag |= INP_IPV4; 481 inp->inp_flags |= INP_HDRINCL; 482 INP_WUNLOCK(inp); 483 return 0; 484 } 485 486 static void 487 div_detach(struct socket *so) 488 { 489 struct inpcb *inp; 490 491 inp = sotoinpcb(so); 492 KASSERT(inp != NULL, ("div_detach: inp == NULL")); 493 INP_INFO_WLOCK(&divcbinfo); 494 INP_WLOCK(inp); 495 in_pcbdetach(inp); 496 in_pcbfree(inp); 497 INP_INFO_WUNLOCK(&divcbinfo); 498 } 499 500 static int 501 div_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 502 { 503 struct inpcb *inp; 504 int error; 505 506 inp = sotoinpcb(so); 507 KASSERT(inp != NULL, ("div_bind: inp == NULL")); 508 /* in_pcbbind assumes that nam is a sockaddr_in 509 * and in_pcbbind requires a valid address. Since divert 510 * sockets don't we need to make sure the address is 511 * filled in properly. 512 * XXX -- divert should not be abusing in_pcbind 513 * and should probably have its own family. 514 */ 515 if (nam->sa_family != AF_INET) 516 return EAFNOSUPPORT; 517 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY; 518 INP_INFO_WLOCK(&divcbinfo); 519 INP_WLOCK(inp); 520 error = in_pcbbind(inp, nam, td->td_ucred); 521 INP_WUNLOCK(inp); 522 INP_INFO_WUNLOCK(&divcbinfo); 523 return error; 524 } 525 526 static int 527 div_shutdown(struct socket *so) 528 { 529 struct inpcb *inp; 530 531 inp = sotoinpcb(so); 532 KASSERT(inp != NULL, ("div_shutdown: inp == NULL")); 533 INP_WLOCK(inp); 534 socantsendmore(so); 535 INP_WUNLOCK(inp); 536 return 0; 537 } 538 539 static int 540 div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, 541 struct mbuf *control, struct thread *td) 542 { 543 /* Packet must have a header (but that's about it) */ 544 if (m->m_len < sizeof (struct ip) && 545 (m = m_pullup(m, sizeof (struct ip))) == 0) { 546 ipstat.ips_toosmall++; 547 m_freem(m); 548 return EINVAL; 549 } 550 551 /* Send packet */ 552 return div_output(so, m, (struct sockaddr_in *)nam, control); 553 } 554 555 void 556 div_ctlinput(int cmd, struct sockaddr *sa, void *vip) 557 { 558 struct in_addr faddr; 559 560 faddr = ((struct sockaddr_in *)sa)->sin_addr; 561 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) 562 return; 563 if (PRC_IS_REDIRECT(cmd)) 564 return; 565 } 566 567 static int 568 div_pcblist(SYSCTL_HANDLER_ARGS) 569 { 570 int error, i, n; 571 struct inpcb *inp, **inp_list; 572 inp_gen_t gencnt; 573 struct xinpgen xig; 574 575 /* 576 * The process of preparing the TCB list is too time-consuming and 577 * resource-intensive to repeat twice on every request. 578 */ 579 if (req->oldptr == 0) { 580 n = divcbinfo.ipi_count; 581 req->oldidx = 2 * (sizeof xig) 582 + (n + n/8) * sizeof(struct xinpcb); 583 return 0; 584 } 585 586 if (req->newptr != 0) 587 return EPERM; 588 589 /* 590 * OK, now we're committed to doing something. 591 */ 592 INP_INFO_RLOCK(&divcbinfo); 593 gencnt = divcbinfo.ipi_gencnt; 594 n = divcbinfo.ipi_count; 595 INP_INFO_RUNLOCK(&divcbinfo); 596 597 error = sysctl_wire_old_buffer(req, 598 2 * sizeof(xig) + n*sizeof(struct xinpcb)); 599 if (error != 0) 600 return (error); 601 602 xig.xig_len = sizeof xig; 603 xig.xig_count = n; 604 xig.xig_gen = gencnt; 605 xig.xig_sogen = so_gencnt; 606 error = SYSCTL_OUT(req, &xig, sizeof xig); 607 if (error) 608 return error; 609 610 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 611 if (inp_list == 0) 612 return ENOMEM; 613 614 INP_INFO_RLOCK(&divcbinfo); 615 for (inp = LIST_FIRST(divcbinfo.ipi_listhead), i = 0; inp && i < n; 616 inp = LIST_NEXT(inp, inp_list)) { 617 INP_RLOCK(inp); 618 if (inp->inp_gencnt <= gencnt && 619 cr_canseesocket(req->td->td_ucred, inp->inp_socket) == 0) 620 inp_list[i++] = inp; 621 INP_RUNLOCK(inp); 622 } 623 INP_INFO_RUNLOCK(&divcbinfo); 624 n = i; 625 626 error = 0; 627 for (i = 0; i < n; i++) { 628 inp = inp_list[i]; 629 INP_RLOCK(inp); 630 if (inp->inp_gencnt <= gencnt) { 631 struct xinpcb xi; 632 bzero(&xi, sizeof(xi)); 633 xi.xi_len = sizeof xi; 634 /* XXX should avoid extra copy */ 635 bcopy(inp, &xi.xi_inp, sizeof *inp); 636 if (inp->inp_socket) 637 sotoxsocket(inp->inp_socket, &xi.xi_socket); 638 INP_RUNLOCK(inp); 639 error = SYSCTL_OUT(req, &xi, sizeof xi); 640 } else 641 INP_RUNLOCK(inp); 642 } 643 if (!error) { 644 /* 645 * Give the user an updated idea of our state. 646 * If the generation differs from what we told 647 * her before, she knows that something happened 648 * while we were processing this request, and it 649 * might be necessary to retry. 650 */ 651 INP_INFO_RLOCK(&divcbinfo); 652 xig.xig_gen = divcbinfo.ipi_gencnt; 653 xig.xig_sogen = so_gencnt; 654 xig.xig_count = divcbinfo.ipi_count; 655 INP_INFO_RUNLOCK(&divcbinfo); 656 error = SYSCTL_OUT(req, &xig, sizeof xig); 657 } 658 free(inp_list, M_TEMP); 659 return error; 660 } 661 662 #ifdef SYSCTL_NODE 663 SYSCTL_NODE(_net_inet, IPPROTO_DIVERT, divert, CTLFLAG_RW, 0, "IPDIVERT"); 664 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLFLAG_RD, 0, 0, 665 div_pcblist, "S,xinpcb", "List of active divert sockets"); 666 #endif 667 668 struct pr_usrreqs div_usrreqs = { 669 .pru_attach = div_attach, 670 .pru_bind = div_bind, 671 .pru_control = in_control, 672 .pru_detach = div_detach, 673 .pru_peeraddr = in_getpeeraddr, 674 .pru_send = div_send, 675 .pru_shutdown = div_shutdown, 676 .pru_sockaddr = in_getsockaddr, 677 .pru_sosetlabel = in_pcbsosetlabel 678 }; 679 680 struct protosw div_protosw = { 681 .pr_type = SOCK_RAW, 682 .pr_protocol = IPPROTO_DIVERT, 683 .pr_flags = PR_ATOMIC|PR_ADDR, 684 .pr_input = div_input, 685 .pr_ctlinput = div_ctlinput, 686 .pr_ctloutput = ip_ctloutput, 687 .pr_init = div_init, 688 .pr_usrreqs = &div_usrreqs 689 }; 690 691 static int 692 div_modevent(module_t mod, int type, void *unused) 693 { 694 int err = 0; 695 int n; 696 697 switch (type) { 698 case MOD_LOAD: 699 /* 700 * Protocol will be initialized by pf_proto_register(). 701 * We don't have to register ip_protox because we are not 702 * a true IP protocol that goes over the wire. 703 */ 704 err = pf_proto_register(PF_INET, &div_protosw); 705 ip_divert_ptr = divert_packet; 706 break; 707 case MOD_QUIESCE: 708 /* 709 * IPDIVERT may normally not be unloaded because of the 710 * potential race conditions. Tell kldunload we can't be 711 * unloaded unless the unload is forced. 712 */ 713 err = EPERM; 714 break; 715 case MOD_UNLOAD: 716 /* 717 * Forced unload. 718 * 719 * Module ipdivert can only be unloaded if no sockets are 720 * connected. Maybe this can be changed later to forcefully 721 * disconnect any open sockets. 722 * 723 * XXXRW: Note that there is a slight race here, as a new 724 * socket open request could be spinning on the lock and then 725 * we destroy the lock. 726 */ 727 INP_INFO_WLOCK(&divcbinfo); 728 n = divcbinfo.ipi_count; 729 if (n != 0) { 730 err = EBUSY; 731 INP_INFO_WUNLOCK(&divcbinfo); 732 break; 733 } 734 ip_divert_ptr = NULL; 735 err = pf_proto_unregister(PF_INET, IPPROTO_DIVERT, SOCK_RAW); 736 INP_INFO_WUNLOCK(&divcbinfo); 737 INP_INFO_LOCK_DESTROY(&divcbinfo); 738 uma_zdestroy(divcbinfo.ipi_zone); 739 break; 740 default: 741 err = EOPNOTSUPP; 742 break; 743 } 744 return err; 745 } 746 747 static moduledata_t ipdivertmod = { 748 "ipdivert", 749 div_modevent, 750 0 751 }; 752 753 DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); 754 MODULE_DEPEND(dummynet, ipfw, 2, 2, 2); 755 MODULE_VERSION(ipdivert, 1); 756