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 #include <sys/vimage.h> 62 63 #include <vm/uma.h> 64 65 #include <net/if.h> 66 #include <net/netisr.h> 67 #include <net/route.h> 68 69 #include <netinet/in.h> 70 #include <netinet/in_pcb.h> 71 #include <netinet/in_systm.h> 72 #include <netinet/in_var.h> 73 #include <netinet/ip.h> 74 #include <netinet/ip_divert.h> 75 #include <netinet/ip_var.h> 76 #include <netinet/ip_fw.h> 77 78 #include <security/mac/mac_framework.h> 79 80 /* 81 * Divert sockets 82 */ 83 84 /* 85 * Allocate enough space to hold a full IP packet 86 */ 87 #define DIVSNDQ (65536 + 100) 88 #define DIVRCVQ (65536 + 100) 89 90 /* 91 * Divert sockets work in conjunction with ipfw, see the divert(4) 92 * manpage for features. 93 * Internally, packets selected by ipfw in ip_input() or ip_output(), 94 * and never diverted before, are passed to the input queue of the 95 * divert socket with a given 'divert_port' number (as specified in 96 * the matching ipfw rule), and they are tagged with a 16 bit cookie 97 * (representing the rule number of the matching ipfw rule), which 98 * is passed to process reading from the socket. 99 * 100 * Packets written to the divert socket are again tagged with a cookie 101 * (usually the same as above) and a destination address. 102 * If the destination address is INADDR_ANY then the packet is 103 * treated as outgoing and sent to ip_output(), otherwise it is 104 * treated as incoming and sent to ip_input(). 105 * In both cases, the packet is tagged with the cookie. 106 * 107 * On reinjection, processing in ip_input() and ip_output() 108 * will be exactly the same as for the original packet, except that 109 * ipfw processing will start at the rule number after the one 110 * written in the cookie (so, tagging a packet with a cookie of 0 111 * will cause it to be effectively considered as a standard packet). 112 */ 113 114 /* Internal variables. */ 115 #ifdef VIMAGE_GLOBALS 116 static struct inpcbhead divcb; 117 static struct inpcbinfo divcbinfo; 118 #endif 119 120 static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */ 121 static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */ 122 123 /* 124 * Initialize divert connection block queue. 125 */ 126 static void 127 div_zone_change(void *tag) 128 { 129 130 uma_zone_set_max(V_divcbinfo.ipi_zone, maxsockets); 131 } 132 133 static int 134 div_inpcb_init(void *mem, int size, int flags) 135 { 136 struct inpcb *inp = mem; 137 138 INP_LOCK_INIT(inp, "inp", "divinp"); 139 return (0); 140 } 141 142 static void 143 div_inpcb_fini(void *mem, int size) 144 { 145 struct inpcb *inp = mem; 146 147 INP_LOCK_DESTROY(inp); 148 } 149 150 void 151 div_init(void) 152 { 153 INIT_VNET_INET(curvnet); 154 155 INP_INFO_LOCK_INIT(&V_divcbinfo, "div"); 156 LIST_INIT(&V_divcb); 157 V_divcbinfo.ipi_listhead = &V_divcb; 158 /* 159 * XXX We don't use the hash list for divert IP, but it's easier 160 * to allocate a one entry hash list than it is to check all 161 * over the place for hashbase == NULL. 162 */ 163 V_divcbinfo.ipi_hashbase = hashinit(1, M_PCB, &V_divcbinfo.ipi_hashmask); 164 V_divcbinfo.ipi_porthashbase = hashinit(1, M_PCB, 165 &V_divcbinfo.ipi_porthashmask); 166 V_divcbinfo.ipi_zone = uma_zcreate("divcb", sizeof(struct inpcb), 167 NULL, NULL, div_inpcb_init, div_inpcb_fini, UMA_ALIGN_PTR, 168 UMA_ZONE_NOFREE); 169 uma_zone_set_max(divcbinfo.ipi_zone, maxsockets); 170 EVENTHANDLER_REGISTER(maxsockets_change, div_zone_change, 171 NULL, EVENTHANDLER_PRI_ANY); 172 } 173 174 /* 175 * IPPROTO_DIVERT is not in the real IP protocol number space; this 176 * function should never be called. Just in case, drop any packets. 177 */ 178 void 179 div_input(struct mbuf *m, int off) 180 { 181 INIT_VNET_INET(curvnet); 182 183 V_ipstat.ips_noproto++; 184 m_freem(m); 185 } 186 187 /* 188 * Divert a packet by passing it up to the divert socket at port 'port'. 189 * 190 * Setup generic address and protocol structures for div_input routine, 191 * then pass them along with mbuf chain. 192 */ 193 static void 194 divert_packet(struct mbuf *m, int incoming) 195 { 196 INIT_VNET_INET(curvnet); 197 struct ip *ip; 198 struct inpcb *inp; 199 struct socket *sa; 200 u_int16_t nport; 201 struct sockaddr_in divsrc; 202 struct m_tag *mtag; 203 204 mtag = m_tag_find(m, PACKET_TAG_DIVERT, NULL); 205 if (mtag == NULL) { 206 printf("%s: no divert tag\n", __func__); 207 m_freem(m); 208 return; 209 } 210 /* Assure header */ 211 if (m->m_len < sizeof(struct ip) && 212 (m = m_pullup(m, sizeof(struct ip))) == 0) 213 return; 214 ip = mtod(m, struct ip *); 215 216 /* Delayed checksums are currently not compatible with divert. */ 217 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 218 ip->ip_len = ntohs(ip->ip_len); 219 in_delayed_cksum(m); 220 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 221 ip->ip_len = htons(ip->ip_len); 222 } 223 224 /* 225 * Record receive interface address, if any. 226 * But only for incoming packets. 227 */ 228 bzero(&divsrc, sizeof(divsrc)); 229 divsrc.sin_len = sizeof(divsrc); 230 divsrc.sin_family = AF_INET; 231 divsrc.sin_port = divert_cookie(mtag); /* record matching rule */ 232 if (incoming) { 233 struct ifaddr *ifa; 234 235 /* Sanity check */ 236 M_ASSERTPKTHDR(m); 237 238 /* Find IP address for receive interface */ 239 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->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 } 247 /* 248 * Record the incoming interface name whenever we have one. 249 */ 250 if (m->m_pkthdr.rcvif) { 251 /* 252 * Hide the actual interface name in there in the 253 * sin_zero array. XXX This needs to be moved to a 254 * different sockaddr type for divert, e.g. 255 * sockaddr_div with multiple fields like 256 * sockaddr_dl. Presently we have only 7 bytes 257 * but that will do for now as most interfaces 258 * are 4 or less + 2 or less bytes for unit. 259 * There is probably a faster way of doing this, 260 * possibly taking it from the sockaddr_dl on the iface. 261 * This solves the problem of a P2P link and a LAN interface 262 * having the same address, which can result in the wrong 263 * interface being assigned to the packet when fed back 264 * into the divert socket. Theoretically if the daemon saves 265 * and re-uses the sockaddr_in as suggested in the man pages, 266 * this iface name will come along for the ride. 267 * (see div_output for the other half of this.) 268 */ 269 strlcpy(divsrc.sin_zero, m->m_pkthdr.rcvif->if_xname, 270 sizeof(divsrc.sin_zero)); 271 } 272 273 /* Put packet on socket queue, if any */ 274 sa = NULL; 275 nport = htons((u_int16_t)divert_info(mtag)); 276 INP_INFO_RLOCK(&V_divcbinfo); 277 LIST_FOREACH(inp, &V_divcb, inp_list) { 278 /* XXX why does only one socket match? */ 279 if (inp->inp_lport == nport) { 280 INP_RLOCK(inp); 281 sa = inp->inp_socket; 282 SOCKBUF_LOCK(&sa->so_rcv); 283 if (sbappendaddr_locked(&sa->so_rcv, 284 (struct sockaddr *)&divsrc, m, 285 (struct mbuf *)0) == 0) { 286 SOCKBUF_UNLOCK(&sa->so_rcv); 287 sa = NULL; /* force mbuf reclaim below */ 288 } else 289 sorwakeup_locked(sa); 290 INP_RUNLOCK(inp); 291 break; 292 } 293 } 294 INP_INFO_RUNLOCK(&V_divcbinfo); 295 if (sa == NULL) { 296 m_freem(m); 297 V_ipstat.ips_noproto++; 298 V_ipstat.ips_delivered--; 299 } 300 } 301 302 /* 303 * Deliver packet back into the IP processing machinery. 304 * 305 * If no address specified, or address is 0.0.0.0, send to ip_output(); 306 * otherwise, send to ip_input() and mark as having been received on 307 * the interface with that address. 308 */ 309 static int 310 div_output(struct socket *so, struct mbuf *m, struct sockaddr_in *sin, 311 struct mbuf *control) 312 { 313 INIT_VNET_INET(curvnet); 314 struct m_tag *mtag; 315 struct divert_tag *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 if ((mtag = m_tag_find(m, PACKET_TAG_DIVERT, NULL)) == NULL) { 331 mtag = m_tag_get(PACKET_TAG_DIVERT, sizeof(struct divert_tag), 332 M_NOWAIT | M_ZERO); 333 if (mtag == NULL) { 334 error = ENOBUFS; 335 goto cantsend; 336 } 337 dt = (struct divert_tag *)(mtag+1); 338 m_tag_prepend(m, mtag); 339 } else 340 dt = (struct divert_tag *)(mtag+1); 341 342 /* Loopback avoidance and state recovery */ 343 if (sin) { 344 int i; 345 346 dt->cookie = sin->sin_port; 347 /* 348 * Find receive interface with the given name, stuffed 349 * (if it exists) in the sin_zero[] field. 350 * The name is user supplied data so don't trust its size 351 * or that it is zero terminated. 352 */ 353 for (i = 0; i < sizeof(sin->sin_zero) && sin->sin_zero[i]; i++) 354 ; 355 if ( i > 0 && i < sizeof(sin->sin_zero)) 356 m->m_pkthdr.rcvif = ifunit(sin->sin_zero); 357 } 358 359 /* Reinject packet into the system as incoming or outgoing */ 360 if (!sin || sin->sin_addr.s_addr == 0) { 361 struct ip *const ip = mtod(m, struct ip *); 362 struct inpcb *inp; 363 364 dt->info |= IP_FW_DIVERT_OUTPUT_FLAG; 365 INP_INFO_WLOCK(&V_divcbinfo); 366 inp = sotoinpcb(so); 367 INP_RLOCK(inp); 368 /* 369 * Don't allow both user specified and setsockopt options, 370 * and don't allow packet length sizes that will crash 371 */ 372 if (((ip->ip_hl != (sizeof (*ip) >> 2)) && inp->inp_options) || 373 ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len)) { 374 error = EINVAL; 375 INP_RUNLOCK(inp); 376 INP_INFO_WUNLOCK(&V_divcbinfo); 377 m_freem(m); 378 } else { 379 /* Convert fields to host order for ip_output() */ 380 ip->ip_len = ntohs(ip->ip_len); 381 ip->ip_off = ntohs(ip->ip_off); 382 383 /* Send packet to output processing */ 384 V_ipstat.ips_rawout++; /* XXX */ 385 386 #ifdef MAC 387 mac_inpcb_create_mbuf(inp, m); 388 #endif 389 /* 390 * Get ready to inject the packet into ip_output(). 391 * Just in case socket options were specified on the 392 * divert socket, we duplicate them. This is done 393 * to avoid having to hold the PCB locks over the call 394 * to ip_output(), as doing this results in a number of 395 * lock ordering complexities. 396 * 397 * Note that we set the multicast options argument for 398 * ip_output() to NULL since it should be invariant that 399 * they are not present. 400 */ 401 KASSERT(inp->inp_moptions == NULL, 402 ("multicast options set on a divert socket")); 403 options = NULL; 404 /* 405 * XXXCSJP: It is unclear to me whether or not it makes 406 * sense for divert sockets to have options. However, 407 * for now we will duplicate them with the INP locks 408 * held so we can use them in ip_output() without 409 * requring a reference to the pcb. 410 */ 411 if (inp->inp_options != NULL) { 412 options = m_dup(inp->inp_options, M_DONTWAIT); 413 if (options == NULL) 414 error = ENOBUFS; 415 } 416 INP_RUNLOCK(inp); 417 INP_INFO_WUNLOCK(&V_divcbinfo); 418 if (error == ENOBUFS) { 419 m_freem(m); 420 return (error); 421 } 422 error = ip_output(m, options, NULL, 423 ((so->so_options & SO_DONTROUTE) ? 424 IP_ROUTETOIF : 0) | IP_ALLOWBROADCAST | 425 IP_RAWOUTPUT, NULL, NULL); 426 if (options != NULL) 427 m_freem(options); 428 } 429 } else { 430 dt->info |= IP_FW_DIVERT_LOOPBACK_FLAG; 431 if (m->m_pkthdr.rcvif == NULL) { 432 /* 433 * No luck with the name, check by IP address. 434 * Clear the port and the ifname to make sure 435 * there are no distractions for ifa_ifwithaddr. 436 */ 437 struct ifaddr *ifa; 438 439 bzero(sin->sin_zero, sizeof(sin->sin_zero)); 440 sin->sin_port = 0; 441 ifa = ifa_ifwithaddr((struct sockaddr *) sin); 442 if (ifa == NULL) { 443 error = EADDRNOTAVAIL; 444 goto cantsend; 445 } 446 m->m_pkthdr.rcvif = ifa->ifa_ifp; 447 } 448 #ifdef MAC 449 SOCK_LOCK(so); 450 mac_socket_create_mbuf(so, m); 451 SOCK_UNLOCK(so); 452 #endif 453 /* Send packet to input processing via netisr */ 454 netisr_queue(NETISR_IP, m); 455 } 456 457 return error; 458 459 cantsend: 460 m_freem(m); 461 return error; 462 } 463 464 static int 465 div_attach(struct socket *so, int proto, struct thread *td) 466 { 467 INIT_VNET_INET(so->so_vnet); 468 struct inpcb *inp; 469 int error; 470 471 inp = sotoinpcb(so); 472 KASSERT(inp == NULL, ("div_attach: inp != NULL")); 473 if (td != NULL) { 474 error = priv_check(td, PRIV_NETINET_DIVERT); 475 if (error) 476 return (error); 477 } 478 error = soreserve(so, div_sendspace, div_recvspace); 479 if (error) 480 return error; 481 INP_INFO_WLOCK(&V_divcbinfo); 482 error = in_pcballoc(so, &V_divcbinfo); 483 if (error) { 484 INP_INFO_WUNLOCK(&V_divcbinfo); 485 return error; 486 } 487 inp = (struct inpcb *)so->so_pcb; 488 INP_INFO_WUNLOCK(&V_divcbinfo); 489 inp->inp_ip_p = proto; 490 inp->inp_vflag |= INP_IPV4; 491 inp->inp_flags |= INP_HDRINCL; 492 INP_WUNLOCK(inp); 493 return 0; 494 } 495 496 static void 497 div_detach(struct socket *so) 498 { 499 INIT_VNET_INET(so->so_vnet); 500 struct inpcb *inp; 501 502 inp = sotoinpcb(so); 503 KASSERT(inp != NULL, ("div_detach: inp == NULL")); 504 INP_INFO_WLOCK(&V_divcbinfo); 505 INP_WLOCK(inp); 506 in_pcbdetach(inp); 507 in_pcbfree(inp); 508 INP_INFO_WUNLOCK(&V_divcbinfo); 509 } 510 511 static int 512 div_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 513 { 514 INIT_VNET_INET(so->so_vnet); 515 struct inpcb *inp; 516 int error; 517 518 inp = sotoinpcb(so); 519 KASSERT(inp != NULL, ("div_bind: inp == NULL")); 520 /* in_pcbbind assumes that nam is a sockaddr_in 521 * and in_pcbbind requires a valid address. Since divert 522 * sockets don't we need to make sure the address is 523 * filled in properly. 524 * XXX -- divert should not be abusing in_pcbind 525 * and should probably have its own family. 526 */ 527 if (nam->sa_family != AF_INET) 528 return EAFNOSUPPORT; 529 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY; 530 INP_INFO_WLOCK(&V_divcbinfo); 531 INP_WLOCK(inp); 532 error = in_pcbbind(inp, nam, td->td_ucred); 533 INP_WUNLOCK(inp); 534 INP_INFO_WUNLOCK(&V_divcbinfo); 535 return error; 536 } 537 538 static int 539 div_shutdown(struct socket *so) 540 { 541 struct inpcb *inp; 542 543 inp = sotoinpcb(so); 544 KASSERT(inp != NULL, ("div_shutdown: inp == NULL")); 545 INP_WLOCK(inp); 546 socantsendmore(so); 547 INP_WUNLOCK(inp); 548 return 0; 549 } 550 551 static int 552 div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, 553 struct mbuf *control, struct thread *td) 554 { 555 INIT_VNET_INET(so->so_vnet); 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 V_ipstat.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 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 INIT_VNET_INET(curvnet); 585 int error, i, n; 586 struct inpcb *inp, **inp_list; 587 inp_gen_t gencnt; 588 struct xinpgen xig; 589 590 /* 591 * The process of preparing the TCB list is too time-consuming and 592 * resource-intensive to repeat twice on every request. 593 */ 594 if (req->oldptr == 0) { 595 n = V_divcbinfo.ipi_count; 596 req->oldidx = 2 * (sizeof xig) 597 + (n + n/8) * sizeof(struct xinpcb); 598 return 0; 599 } 600 601 if (req->newptr != 0) 602 return EPERM; 603 604 /* 605 * OK, now we're committed to doing something. 606 */ 607 INP_INFO_RLOCK(&V_divcbinfo); 608 gencnt = V_divcbinfo.ipi_gencnt; 609 n = V_divcbinfo.ipi_count; 610 INP_INFO_RUNLOCK(&V_divcbinfo); 611 612 error = sysctl_wire_old_buffer(req, 613 2 * sizeof(xig) + n*sizeof(struct xinpcb)); 614 if (error != 0) 615 return (error); 616 617 xig.xig_len = sizeof xig; 618 xig.xig_count = n; 619 xig.xig_gen = gencnt; 620 xig.xig_sogen = so_gencnt; 621 error = SYSCTL_OUT(req, &xig, sizeof xig); 622 if (error) 623 return error; 624 625 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK); 626 if (inp_list == 0) 627 return ENOMEM; 628 629 INP_INFO_RLOCK(&V_divcbinfo); 630 for (inp = LIST_FIRST(V_divcbinfo.ipi_listhead), i = 0; inp && i < n; 631 inp = LIST_NEXT(inp, inp_list)) { 632 INP_RLOCK(inp); 633 if (inp->inp_gencnt <= gencnt && 634 cr_canseeinpcb(req->td->td_ucred, inp) == 0) 635 inp_list[i++] = inp; 636 INP_RUNLOCK(inp); 637 } 638 INP_INFO_RUNLOCK(&V_divcbinfo); 639 n = i; 640 641 error = 0; 642 for (i = 0; i < n; i++) { 643 inp = inp_list[i]; 644 INP_RLOCK(inp); 645 if (inp->inp_gencnt <= gencnt) { 646 struct xinpcb xi; 647 bzero(&xi, sizeof(xi)); 648 xi.xi_len = sizeof xi; 649 /* XXX should avoid extra copy */ 650 bcopy(inp, &xi.xi_inp, sizeof *inp); 651 if (inp->inp_socket) 652 sotoxsocket(inp->inp_socket, &xi.xi_socket); 653 INP_RUNLOCK(inp); 654 error = SYSCTL_OUT(req, &xi, sizeof xi); 655 } else 656 INP_RUNLOCK(inp); 657 } 658 if (!error) { 659 /* 660 * Give the user an updated idea of our state. 661 * If the generation differs from what we told 662 * her before, she knows that something happened 663 * while we were processing this request, and it 664 * might be necessary to retry. 665 */ 666 INP_INFO_RLOCK(&V_divcbinfo); 667 xig.xig_gen = V_divcbinfo.ipi_gencnt; 668 xig.xig_sogen = so_gencnt; 669 xig.xig_count = V_divcbinfo.ipi_count; 670 INP_INFO_RUNLOCK(&V_divcbinfo); 671 error = SYSCTL_OUT(req, &xig, sizeof xig); 672 } 673 free(inp_list, M_TEMP); 674 return error; 675 } 676 677 #ifdef SYSCTL_NODE 678 SYSCTL_NODE(_net_inet, IPPROTO_DIVERT, divert, CTLFLAG_RW, 0, "IPDIVERT"); 679 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLFLAG_RD, 0, 0, 680 div_pcblist, "S,xinpcb", "List of active divert sockets"); 681 #endif 682 683 struct pr_usrreqs div_usrreqs = { 684 .pru_attach = div_attach, 685 .pru_bind = div_bind, 686 .pru_control = in_control, 687 .pru_detach = div_detach, 688 .pru_peeraddr = in_getpeeraddr, 689 .pru_send = div_send, 690 .pru_shutdown = div_shutdown, 691 .pru_sockaddr = in_getsockaddr, 692 .pru_sosetlabel = in_pcbsosetlabel 693 }; 694 695 struct protosw div_protosw = { 696 .pr_type = SOCK_RAW, 697 .pr_protocol = IPPROTO_DIVERT, 698 .pr_flags = PR_ATOMIC|PR_ADDR, 699 .pr_input = div_input, 700 .pr_ctlinput = div_ctlinput, 701 .pr_ctloutput = ip_ctloutput, 702 .pr_init = div_init, 703 .pr_usrreqs = &div_usrreqs 704 }; 705 706 static int 707 div_modevent(module_t mod, int type, void *unused) 708 { 709 int err = 0; 710 int n; 711 712 switch (type) { 713 case MOD_LOAD: 714 /* 715 * Protocol will be initialized by pf_proto_register(). 716 * We don't have to register ip_protox because we are not 717 * a true IP protocol that goes over the wire. 718 */ 719 err = pf_proto_register(PF_INET, &div_protosw); 720 ip_divert_ptr = divert_packet; 721 break; 722 case MOD_QUIESCE: 723 /* 724 * IPDIVERT may normally not be unloaded because of the 725 * potential race conditions. Tell kldunload we can't be 726 * unloaded unless the unload is forced. 727 */ 728 err = EPERM; 729 break; 730 case MOD_UNLOAD: 731 /* 732 * Forced unload. 733 * 734 * Module ipdivert can only be unloaded if no sockets are 735 * connected. Maybe this can be changed later to forcefully 736 * disconnect any open sockets. 737 * 738 * XXXRW: Note that there is a slight race here, as a new 739 * socket open request could be spinning on the lock and then 740 * we destroy the lock. 741 */ 742 INP_INFO_WLOCK(&V_divcbinfo); 743 n = V_divcbinfo.ipi_count; 744 if (n != 0) { 745 err = EBUSY; 746 INP_INFO_WUNLOCK(&V_divcbinfo); 747 break; 748 } 749 ip_divert_ptr = NULL; 750 err = pf_proto_unregister(PF_INET, IPPROTO_DIVERT, SOCK_RAW); 751 INP_INFO_WUNLOCK(&V_divcbinfo); 752 INP_INFO_LOCK_DESTROY(&V_divcbinfo); 753 uma_zdestroy(V_divcbinfo.ipi_zone); 754 break; 755 default: 756 err = EOPNOTSUPP; 757 break; 758 } 759 return err; 760 } 761 762 static moduledata_t ipdivertmod = { 763 "ipdivert", 764 div_modevent, 765 0 766 }; 767 768 DECLARE_MODULE(ipdivert, ipdivertmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); 769 MODULE_DEPEND(dummynet, ipfw, 2, 2, 2); 770 MODULE_VERSION(ipdivert, 1); 771