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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD: src/sys/netinet/ip_divert.c,v 1.42.2.6 2003/01/23 21:06:45 sam Exp $ 34 * $DragonFly: src/sys/netinet/ip_divert.c,v 1.40 2008/10/21 13:51:01 sephe Exp $ 35 */ 36 37 #define _IP_VHL 38 39 #include "opt_inet.h" 40 #include "opt_ipfw.h" 41 #include "opt_ipdivert.h" 42 #include "opt_ipsec.h" 43 44 #ifndef INET 45 #error "IPDIVERT requires INET." 46 #endif 47 48 #include <sys/param.h> 49 #include <sys/kernel.h> 50 #include <sys/malloc.h> 51 #include <sys/mbuf.h> 52 #include <sys/socket.h> 53 #include <sys/protosw.h> 54 #include <sys/socketvar.h> 55 #include <sys/sysctl.h> 56 #include <sys/systm.h> 57 #include <sys/proc.h> 58 #include <sys/priv.h> 59 #include <sys/thread2.h> 60 #include <sys/in_cksum.h> 61 #include <sys/lock.h> 62 #ifdef SMP 63 #include <sys/msgport.h> 64 #endif 65 66 #include <vm/vm_zone.h> 67 68 #include <net/if.h> 69 #include <net/route.h> 70 #ifdef SMP 71 #include <net/netmsg2.h> 72 #endif 73 74 #include <netinet/in.h> 75 #include <netinet/in_systm.h> 76 #include <netinet/ip.h> 77 #include <netinet/in_pcb.h> 78 #include <netinet/in_var.h> 79 #include <netinet/ip_var.h> 80 #include <netinet/ip_divert.h> 81 82 /* 83 * Divert sockets 84 */ 85 86 /* 87 * Allocate enough space to hold a full IP packet 88 */ 89 #define DIVSNDQ (65536 + 100) 90 #define DIVRCVQ (65536 + 100) 91 92 #define DIV_IS_OUTPUT(sin) ((sin) == NULL || (sin)->sin_addr.s_addr == 0) 93 94 #define DIV_OUTPUT 0x10000 95 #define DIV_INPUT 0x20000 96 97 /* 98 * Divert sockets work in conjunction with ipfw, see the divert(4) 99 * manpage for features. 100 * Internally, packets selected by ipfw in ip_input() or ip_output(), 101 * and never diverted before, are passed to the input queue of the 102 * divert socket with a given 'divert_port' number (as specified in 103 * the matching ipfw rule), and they are tagged with a 16 bit cookie 104 * (representing the rule number of the matching ipfw rule), which 105 * is passed to process reading from the socket. 106 * 107 * Packets written to the divert socket are again tagged with a cookie 108 * (usually the same as above) and a destination address. 109 * If the destination address is INADDR_ANY then the packet is 110 * treated as outgoing and sent to ip_output(), otherwise it is 111 * treated as incoming and sent to ip_input(). 112 * In both cases, the packet is tagged with the cookie. 113 * 114 * On reinjection, processing in ip_input() and ip_output() 115 * will be exactly the same as for the original packet, except that 116 * ipfw processing will start at the rule number after the one 117 * written in the cookie (so, tagging a packet with a cookie of 0 118 * will cause it to be effectively considered as a standard packet). 119 */ 120 121 /* Internal variables */ 122 static struct inpcbinfo divcbinfo; 123 124 static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */ 125 static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */ 126 127 static struct mbuf *ip_divert(struct mbuf *, int, int); 128 129 /* 130 * Initialize divert connection block queue. 131 */ 132 void 133 div_init(void) 134 { 135 in_pcbinfo_init(&divcbinfo); 136 /* 137 * XXX We don't use the hash list for divert IP, but it's easier 138 * to allocate a one entry hash list than it is to check all 139 * over the place for hashbase == NULL. 140 */ 141 divcbinfo.hashbase = hashinit(1, M_PCB, &divcbinfo.hashmask); 142 divcbinfo.porthashbase = hashinit(1, M_PCB, &divcbinfo.porthashmask); 143 divcbinfo.wildcardhashbase = hashinit(1, M_PCB, 144 &divcbinfo.wildcardhashmask); 145 divcbinfo.ipi_zone = zinit("divcb", sizeof(struct inpcb), 146 maxsockets, ZONE_INTERRUPT, 0); 147 ip_divert_p = ip_divert; 148 } 149 150 /* 151 * IPPROTO_DIVERT is not a real IP protocol; don't allow any packets 152 * with that protocol number to enter the system from the outside. 153 */ 154 void 155 div_input(struct mbuf *m, ...) 156 { 157 ipstat.ips_noproto++; 158 m_freem(m); 159 } 160 161 struct lwkt_port * 162 div_soport(struct socket *so, struct sockaddr *nam, 163 struct mbuf **mptr, int req) 164 { 165 struct sockaddr_in *sin; 166 struct mbuf *m; 167 int dir; 168 169 /* Except for send(), everything happens on CPU0 */ 170 if (req != PRU_SEND) 171 return cpu0_soport(so, nam, mptr, req); 172 173 sin = (struct sockaddr_in *)nam; 174 m = *mptr; 175 M_ASSERTPKTHDR(m); 176 177 m->m_pkthdr.rcvif = NULL; 178 dir = DIV_IS_OUTPUT(sin) ? IP_MPORT_OUT : IP_MPORT_IN; 179 180 if (sin != NULL) { 181 int i; 182 183 /* 184 * Try locating the interface, if we originally had one. 185 * This is done even for outgoing packets, since for a 186 * forwarded packet, there must be an interface attached. 187 * 188 * Find receive interface with the given name, stuffed 189 * (if it exists) in the sin_zero[] field. 190 * The name is user supplied data so don't trust its size 191 * or that it is zero terminated. 192 */ 193 for (i = 0; sin->sin_zero[i] && i < sizeof(sin->sin_zero); i++) 194 ; 195 if (i > 0 && i < sizeof(sin->sin_zero)) 196 m->m_pkthdr.rcvif = ifunit(sin->sin_zero); 197 } 198 199 if (dir == IP_MPORT_IN && m->m_pkthdr.rcvif == NULL) { 200 /* 201 * No luck with the name, check by IP address. 202 * Clear the port and the ifname to make sure 203 * there are no distractions for ifa_ifwithaddr. 204 * 205 * Be careful not to trash sin->sin_port; it will 206 * be used later in div_output(). 207 */ 208 struct ifaddr *ifa; 209 u_short sin_port; 210 211 bzero(sin->sin_zero, sizeof(sin->sin_zero)); 212 sin_port = sin->sin_port; /* save */ 213 sin->sin_port = 0; 214 ifa = ifa_ifwithaddr((struct sockaddr *)sin); 215 if (ifa == NULL) { 216 m_freem(m); 217 *mptr = NULL; 218 return NULL; 219 } 220 sin->sin_port = sin_port; /* restore */ 221 m->m_pkthdr.rcvif = ifa->ifa_ifp; 222 } 223 224 return ip_mport(mptr, dir); 225 } 226 227 /* 228 * Divert a packet by passing it up to the divert socket at port 'port'. 229 * 230 * Setup generic address and protocol structures for div_input routine, 231 * then pass them along with mbuf chain. 232 */ 233 static void 234 div_packet(struct mbuf *m, int incoming, int port) 235 { 236 struct sockaddr_in divsrc = { sizeof divsrc, AF_INET }; 237 struct inpcb *inp; 238 struct socket *sa; 239 struct m_tag *mtag; 240 struct divert_info *divinfo; 241 u_int16_t nport; 242 243 /* Locate the divert info */ 244 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL); 245 divinfo = m_tag_data(mtag); 246 divsrc.sin_port = divinfo->skipto; 247 248 /* 249 * Record receive interface address, if any. 250 * But only for incoming packets. 251 */ 252 divsrc.sin_addr.s_addr = 0; 253 if (incoming) { 254 struct ifaddr_container *ifac; 255 256 /* Find IP address for receive interface */ 257 TAILQ_FOREACH(ifac, &m->m_pkthdr.rcvif->if_addrheads[mycpuid], 258 ifa_link) { 259 struct ifaddr *ifa = ifac->ifa; 260 261 if (ifa->ifa_addr == NULL) 262 continue; 263 if (ifa->ifa_addr->sa_family != AF_INET) 264 continue; 265 divsrc.sin_addr = 266 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr; 267 break; 268 } 269 } 270 /* 271 * Record the incoming interface name whenever we have one. 272 */ 273 if (m->m_pkthdr.rcvif) { 274 /* 275 * Hide the actual interface name in there in the 276 * sin_zero array. XXX This needs to be moved to a 277 * different sockaddr type for divert, e.g. 278 * sockaddr_div with multiple fields like 279 * sockaddr_dl. Presently we have only 7 bytes 280 * but that will do for now as most interfaces 281 * are 4 or less + 2 or less bytes for unit. 282 * There is probably a faster way of doing this, 283 * possibly taking it from the sockaddr_dl on the iface. 284 * This solves the problem of a P2P link and a LAN interface 285 * having the same address, which can result in the wrong 286 * interface being assigned to the packet when fed back 287 * into the divert socket. Theoretically if the daemon saves 288 * and re-uses the sockaddr_in as suggested in the man pages, 289 * this iface name will come along for the ride. 290 * (see div_output for the other half of this.) 291 */ 292 ksnprintf(divsrc.sin_zero, sizeof divsrc.sin_zero, 293 m->m_pkthdr.rcvif->if_xname); 294 } 295 296 /* Put packet on socket queue, if any */ 297 sa = NULL; 298 nport = htons((u_int16_t)port); 299 300 /* 301 * XXX 302 * Following loop to locate the inpcb is MPSAFE since the inpcb 303 * insertion/removal happens on the same CPU (CPU0), however, 304 * saving/testing the socket pointer is not MPSAFE. So we still 305 * need to hold BGL here. 306 */ 307 get_mplock(); 308 LIST_FOREACH(inp, &divcbinfo.pcblisthead, inp_list) { 309 if (inp->inp_flags & INP_PLACEMARKER) 310 continue; 311 if (inp->inp_lport == nport) 312 sa = inp->inp_socket; 313 } 314 if (sa) { 315 if (ssb_appendaddr(&sa->so_rcv, (struct sockaddr *)&divsrc, m, 316 (struct mbuf *)NULL) == 0) 317 m_freem(m); 318 else 319 sorwakeup(sa); 320 rel_mplock(); 321 } else { 322 rel_mplock(); 323 m_freem(m); 324 ipstat.ips_noproto++; 325 ipstat.ips_delivered--; 326 } 327 } 328 329 #ifdef SMP 330 static void 331 div_packet_handler(struct netmsg *nmsg) 332 { 333 struct netmsg_packet *nmp; 334 struct lwkt_msg *msg; 335 struct mbuf *m; 336 int port, incoming = 0; 337 338 nmp = (struct netmsg_packet *)nmsg; 339 m = nmp->nm_packet; 340 341 msg = &nmsg->nm_lmsg; 342 port = msg->u.ms_result32 & 0xffff; 343 if (msg->u.ms_result32 & DIV_INPUT) 344 incoming = 1; 345 346 div_packet(m, incoming, port); 347 } 348 #endif /* SMP */ 349 350 static void 351 divert_packet(struct mbuf *m, int incoming) 352 { 353 struct m_tag *mtag; 354 struct divert_info *divinfo; 355 int port; 356 357 M_ASSERTPKTHDR(m); 358 359 /* Assure header */ 360 if (m->m_len < sizeof(struct ip) && 361 (m = m_pullup(m, sizeof(struct ip))) == NULL) 362 return; 363 364 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL); 365 KASSERT(mtag != NULL, ("%s no divert tag!", __func__)); 366 divinfo = m_tag_data(mtag); 367 368 port = divinfo->port; 369 KASSERT(port != 0, ("%s: port=0", __func__)); 370 371 #ifdef SMP 372 if (mycpuid != 0) { 373 struct netmsg_packet *nmp; 374 struct lwkt_msg *msg; 375 376 nmp = &m->m_hdr.mh_netmsg; 377 netmsg_init(&nmp->nm_netmsg, &netisr_apanic_rport, MSGF_MPSAFE, 378 div_packet_handler); 379 nmp->nm_packet = m; 380 381 msg = &nmp->nm_netmsg.nm_lmsg; 382 msg->u.ms_result32 = port; /* port is 16bits */ 383 if (incoming) 384 msg->u.ms_result32 |= DIV_INPUT; 385 else 386 msg->u.ms_result32 |= DIV_OUTPUT; 387 388 lwkt_sendmsg(cpu_portfn(0), &nmp->nm_netmsg.nm_lmsg); 389 } else 390 #endif 391 div_packet(m, incoming, port); 392 } 393 394 /* 395 * Deliver packet back into the IP processing machinery. 396 * 397 * If no address specified, or address is 0.0.0.0, send to ip_output(); 398 * otherwise, send to ip_input() and mark as having been received on 399 * the interface with that address. 400 */ 401 static int 402 div_output(struct socket *so, struct mbuf *m, 403 struct sockaddr_in *sin, struct mbuf *control) 404 { 405 int error = 0; 406 struct m_tag *mtag; 407 struct divert_info *divinfo; 408 409 if (control) 410 m_freem(control); /* XXX */ 411 412 /* 413 * Prepare the tag for divert info. Note that a packet 414 * with a 0 tag in mh_data is effectively untagged, 415 * so we could optimize that case. 416 */ 417 mtag = m_tag_get(PACKET_TAG_IPFW_DIVERT, sizeof(*divinfo), MB_DONTWAIT); 418 if (mtag == NULL) { 419 error = ENOBUFS; 420 goto cantsend; 421 } 422 m_tag_prepend(m, mtag); 423 424 /* Loopback avoidance and state recovery */ 425 divinfo = m_tag_data(mtag); 426 if (sin) 427 divinfo->skipto = sin->sin_port; 428 else 429 divinfo->skipto = 0; 430 431 /* Reinject packet into the system as incoming or outgoing */ 432 if (DIV_IS_OUTPUT(sin)) { 433 struct ip *const ip = mtod(m, struct ip *); 434 435 /* Don't allow packet length sizes that will crash */ 436 if ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len) { 437 error = EINVAL; 438 goto cantsend; 439 } 440 441 /* Convert fields to host order for ip_output() */ 442 ip->ip_len = ntohs(ip->ip_len); 443 ip->ip_off = ntohs(ip->ip_off); 444 445 /* Send packet to output processing */ 446 ipstat.ips_rawout++; /* XXX */ 447 error = ip_output(m, NULL, NULL, 448 (so->so_options & SO_DONTROUTE) | 449 IP_ALLOWBROADCAST | IP_RAWOUTPUT, 450 NULL, NULL); 451 } else { 452 ip_input(m); 453 } 454 return error; 455 456 cantsend: 457 m_freem(m); 458 return error; 459 } 460 461 static int 462 div_attach(struct socket *so, int proto, struct pru_attach_info *ai) 463 { 464 struct inpcb *inp; 465 int error; 466 467 inp = so->so_pcb; 468 if (inp) 469 panic("div_attach"); 470 if ((error = priv_check_cred(ai->p_ucred, PRIV_ROOT, NULL_CRED_OKAY)) != 0) 471 return error; 472 473 error = soreserve(so, div_sendspace, div_recvspace, ai->sb_rlimit); 474 if (error) 475 return error; 476 error = in_pcballoc(so, &divcbinfo); 477 if (error) 478 return error; 479 inp = (struct inpcb *)so->so_pcb; 480 inp->inp_ip_p = proto; 481 inp->inp_vflag |= INP_IPV4; 482 inp->inp_flags |= INP_HDRINCL; 483 /* 484 * The socket is always "connected" because 485 * we always know "where" to send the packet. 486 */ 487 so->so_state |= SS_ISCONNECTED; 488 return 0; 489 } 490 491 static int 492 div_detach(struct socket *so) 493 { 494 struct inpcb *inp; 495 496 inp = so->so_pcb; 497 if (inp == NULL) 498 panic("div_detach"); 499 in_pcbdetach(inp); 500 return 0; 501 } 502 503 static int 504 div_abort(struct socket *so) 505 { 506 soisdisconnected(so); 507 return div_detach(so); 508 } 509 510 static int 511 div_disconnect(struct socket *so) 512 { 513 if (!(so->so_state & SS_ISCONNECTED)) 514 return ENOTCONN; 515 return div_abort(so); 516 } 517 518 static int 519 div_bind(struct socket *so, struct sockaddr *nam, struct thread *td) 520 { 521 int error; 522 523 /* 524 * in_pcbbind assumes that nam is a sockaddr_in 525 * and in_pcbbind requires a valid address. Since divert 526 * sockets don't we need to make sure the address is 527 * filled in properly. 528 * XXX -- divert should not be abusing in_pcbind 529 * and should probably have its own family. 530 */ 531 if (nam->sa_family != AF_INET) { 532 error = EAFNOSUPPORT; 533 } else { 534 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY; 535 error = in_pcbbind(so->so_pcb, nam, td); 536 } 537 return error; 538 } 539 540 static int 541 div_shutdown(struct socket *so) 542 { 543 socantsendmore(so); 544 return 0; 545 } 546 547 static int 548 div_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam, 549 struct mbuf *control, struct thread *td) 550 { 551 /* Length check already done in ip_mport() */ 552 KASSERT(m->m_len >= sizeof(struct ip), ("IP header not in one mbuf")); 553 554 /* Send packet */ 555 return div_output(so, m, (struct sockaddr_in *)nam, control); 556 } 557 558 SYSCTL_DECL(_net_inet_divert); 559 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLFLAG_RD, &divcbinfo, 0, 560 in_pcblist_global, "S,xinpcb", "List of active divert sockets"); 561 562 struct pr_usrreqs div_usrreqs = { 563 .pru_abort = div_abort, 564 .pru_accept = pru_accept_notsupp, 565 .pru_attach = div_attach, 566 .pru_bind = div_bind, 567 .pru_connect = pru_connect_notsupp, 568 .pru_connect2 = pru_connect2_notsupp, 569 .pru_control = in_control, 570 .pru_detach = div_detach, 571 .pru_disconnect = div_disconnect, 572 .pru_listen = pru_listen_notsupp, 573 .pru_peeraddr = in_setpeeraddr, 574 .pru_rcvd = pru_rcvd_notsupp, 575 .pru_rcvoob = pru_rcvoob_notsupp, 576 .pru_send = div_send, 577 .pru_sense = pru_sense_null, 578 .pru_shutdown = div_shutdown, 579 .pru_sockaddr = in_setsockaddr, 580 .pru_sosend = sosend, 581 .pru_soreceive = soreceive, 582 .pru_sopoll = sopoll 583 }; 584 585 static struct mbuf * 586 ip_divert_out(struct mbuf *m, int tee) 587 { 588 struct mbuf *clone = NULL; 589 struct ip *ip = mtod(m, struct ip *); 590 591 /* Clone packet if we're doing a 'tee' */ 592 if (tee) 593 clone = m_dup(m, MB_DONTWAIT); 594 595 /* 596 * XXX 597 * delayed checksums are not currently compatible 598 * with divert sockets. 599 */ 600 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 601 in_delayed_cksum(m); 602 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 603 } 604 605 /* Restore packet header fields to original values */ 606 ip->ip_len = htons(ip->ip_len); 607 ip->ip_off = htons(ip->ip_off); 608 609 /* Deliver packet to divert input routine */ 610 divert_packet(m, 0); 611 612 /* If 'tee', continue with original packet */ 613 return clone; 614 } 615 616 static struct mbuf * 617 ip_divert_in(struct mbuf *m, int tee) 618 { 619 struct mbuf *clone = NULL; 620 struct ip *ip = mtod(m, struct ip *); 621 struct m_tag *mtag; 622 623 if (ip->ip_off & (IP_MF | IP_OFFMASK)) { 624 const struct divert_info *divinfo; 625 u_short frag_off; 626 int hlen; 627 628 /* 629 * Only trust divert info in the fragment 630 * at offset 0. 631 */ 632 frag_off = ip->ip_off << 3; 633 if (frag_off != 0) { 634 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL); 635 m_tag_delete(m, mtag); 636 } 637 638 /* 639 * Attempt reassembly; if it succeeds, proceed. 640 * ip_reass() will return a different mbuf. 641 */ 642 m = ip_reass(m); 643 if (m == NULL) 644 return NULL; 645 ip = mtod(m, struct ip *); 646 647 /* Caller need to redispatch the packet, if it is for us */ 648 m->m_pkthdr.fw_flags |= FW_MBUF_REDISPATCH; 649 650 /* 651 * Get the header length of the reassembled 652 * packet 653 */ 654 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 655 656 /* 657 * Restore original checksum before diverting 658 * packet 659 */ 660 ip->ip_len += hlen; 661 ip->ip_len = htons(ip->ip_len); 662 ip->ip_off = htons(ip->ip_off); 663 ip->ip_sum = 0; 664 if (hlen == sizeof(struct ip)) 665 ip->ip_sum = in_cksum_hdr(ip); 666 else 667 ip->ip_sum = in_cksum(m, hlen); 668 ip->ip_off = ntohs(ip->ip_off); 669 ip->ip_len = ntohs(ip->ip_len); 670 671 /* 672 * Only use the saved divert info 673 */ 674 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL); 675 if (mtag == NULL) { 676 /* Wrongly configured ipfw */ 677 kprintf("ip_input no divert info\n"); 678 m_freem(m); 679 return NULL; 680 } 681 divinfo = m_tag_data(mtag); 682 tee = divinfo->tee; 683 } 684 685 /* 686 * Divert or tee packet to the divert protocol if 687 * required. 688 */ 689 690 /* Clone packet if we're doing a 'tee' */ 691 if (tee) 692 clone = m_dup(m, MB_DONTWAIT); 693 694 /* 695 * Restore packet header fields to original 696 * values 697 */ 698 ip->ip_len = htons(ip->ip_len); 699 ip->ip_off = htons(ip->ip_off); 700 701 /* Deliver packet to divert input routine */ 702 divert_packet(m, 1); 703 704 /* Catch invalid reference */ 705 m = NULL; 706 ip = NULL; 707 708 ipstat.ips_delivered++; 709 710 /* If 'tee', continue with original packet */ 711 if (clone != NULL) { 712 /* 713 * Complete processing of the packet. 714 * XXX Better safe than sorry, remove the DIVERT tag. 715 */ 716 mtag = m_tag_find(clone, PACKET_TAG_IPFW_DIVERT, NULL); 717 KKASSERT(mtag != NULL); 718 m_tag_delete(clone, mtag); 719 } 720 return clone; 721 } 722 723 static struct mbuf * 724 ip_divert(struct mbuf *m, int tee, int incoming) 725 { 726 struct mbuf *ret; 727 728 if (incoming) 729 ret = ip_divert_in(m, tee); 730 else 731 ret = ip_divert_out(m, tee); 732 return ret; 733 } 734