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sys/netinet/ip_output.c
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1 /*- 2 * Copyright (c) 1982, 1986, 1988, 1990, 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 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD: releng/9.1/sys/netinet/ip_output.c 238713 2012-07-23 09:19:14Z glebius $"); 34 35 #include "opt_ipfw.h" 36 #include "opt_ipsec.h" 37 #include "opt_route.h" 38 #include "opt_mbuf_stress_test.h" 39 #include "opt_mpath.h" 40 #include "opt_sctp.h" 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/kernel.h> 45 #include <sys/malloc.h> 46 #include <sys/mbuf.h> 47 #include <sys/priv.h> 48 #include <sys/proc.h> 49 #include <sys/protosw.h> 50 #include <sys/socket.h> 51 #include <sys/socketvar.h> 52 #include <sys/sysctl.h> 53 #include <sys/ucred.h> 54 55 #include <net/if.h> 56 #include <net/if_llatbl.h> 57 #include <net/netisr.h> 58 #include <net/pfil.h> 59 #include <net/route.h> 60 #include <net/flowtable.h> 61 #ifdef RADIX_MPATH 62 #include <net/radix_mpath.h> 63 #endif 64 #include <net/vnet.h> 65 66 #include <netinet/in.h> 67 #include <netinet/in_systm.h> 68 #include <netinet/ip.h> 69 #include <netinet/in_pcb.h> 70 #include <netinet/in_var.h> 71 #include <netinet/ip_var.h> 72 #include <netinet/ip_options.h> 73 #ifdef SCTP 74 #include <netinet/sctp.h> 75 #include <netinet/sctp_crc32.h> 76 #endif 77 78 #ifdef IPSEC 79 #include <netinet/ip_ipsec.h> 80 #include <netipsec/ipsec.h> 81 #endif /* IPSEC*/ 82 83 #include <machine/in_cksum.h> 84 85 #include <security/mac/mac_framework.h> 86 87 VNET_DEFINE(u_short, ip_id); 88 89 #ifdef MBUF_STRESS_TEST 90 static int mbuf_frag_size = 0; 91 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW, 92 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size"); 93 #endif 94 95 static void ip_mloopback 96 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int); 97 98 99 extern int in_mcast_loop; 100 extern struct protosw inetsw[]; 101 102 /* 103 * IP output. The packet in mbuf chain m contains a skeletal IP 104 * header (with len, off, ttl, proto, tos, src, dst). 105 * ip_len and ip_off are in host format. 106 * The mbuf chain containing the packet will be freed. 107 * The mbuf opt, if present, will not be freed. 108 * In the IP forwarding case, the packet will arrive with options already 109 * inserted, so must have a NULL opt pointer. 110 */ 111 int 112 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags, 113 struct ip_moptions *imo, struct inpcb *inp) 114 { 115 struct ip *ip; 116 struct ifnet *ifp = NULL; /* keep compiler happy */ 117 struct mbuf *m0; 118 int hlen = sizeof (struct ip); 119 int mtu; 120 int n; /* scratchpad */ 121 int error = 0; 122 int nortfree = 0; 123 struct sockaddr_in *dst; 124 struct in_ifaddr *ia; 125 int isbroadcast, sw_csum; 126 struct route iproute; 127 struct rtentry *rte; /* cache for ro->ro_rt */ 128 struct in_addr odst; 129 #ifdef IPFIREWALL_FORWARD 130 struct m_tag *fwd_tag = NULL; 131 #endif 132 #ifdef IPSEC 133 int no_route_but_check_spd = 0; 134 #endif 135 M_ASSERTPKTHDR(m); 136 137 if (inp != NULL) { 138 INP_LOCK_ASSERT(inp); 139 M_SETFIB(m, inp->inp_inc.inc_fibnum); 140 if (inp->inp_flags & (INP_HW_FLOWID|INP_SW_FLOWID)) { 141 m->m_pkthdr.flowid = inp->inp_flowid; 142 m->m_flags |= M_FLOWID; 143 } 144 } 145 146 if (ro == NULL) { 147 ro = &iproute; 148 bzero(ro, sizeof (*ro)); 149 150 #ifdef FLOWTABLE 151 { 152 struct flentry *fle; 153 154 /* 155 * The flow table returns route entries valid for up to 30 156 * seconds; we rely on the remainder of ip_output() taking no 157 * longer than that long for the stability of ro_rt. The 158 * flow ID assignment must have happened before this point. 159 */ 160 if ((fle = flowtable_lookup_mbuf(V_ip_ft, m, AF_INET)) != NULL) { 161 flow_to_route(fle, ro); 162 nortfree = 1; 163 } 164 } 165 #endif 166 } 167 168 if (opt) { 169 int len = 0; 170 m = ip_insertoptions(m, opt, &len); 171 if (len != 0) 172 hlen = len; /* ip->ip_hl is updated above */ 173 } 174 ip = mtod(m, struct ip *); 175 176 /* 177 * Fill in IP header. If we are not allowing fragmentation, 178 * then the ip_id field is meaningless, but we don't set it 179 * to zero. Doing so causes various problems when devices along 180 * the path (routers, load balancers, firewalls, etc.) illegally 181 * disable DF on our packet. Note that a 16-bit counter 182 * will wrap around in less than 10 seconds at 100 Mbit/s on a 183 * medium with MTU 1500. See Steven M. Bellovin, "A Technique 184 * for Counting NATted Hosts", Proc. IMW'02, available at 185 * <http://www.cs.columbia.edu/~smb/papers/fnat.pdf>. 186 */ 187 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) { 188 ip->ip_v = IPVERSION; 189 ip->ip_hl = hlen >> 2; 190 ip->ip_id = ip_newid(); 191 IPSTAT_INC(ips_localout); 192 } else { 193 /* Header already set, fetch hlen from there */ 194 hlen = ip->ip_hl << 2; 195 } 196 197 dst = (struct sockaddr_in *)&ro->ro_dst; 198 again: 199 ia = NULL; 200 /* 201 * If there is a cached route, 202 * check that it is to the same destination 203 * and is still up. If not, free it and try again. 204 * The address family should also be checked in case of sharing the 205 * cache with IPv6. 206 */ 207 rte = ro->ro_rt; 208 if (rte && ((rte->rt_flags & RTF_UP) == 0 || 209 rte->rt_ifp == NULL || 210 !RT_LINK_IS_UP(rte->rt_ifp) || 211 dst->sin_family != AF_INET || 212 dst->sin_addr.s_addr != ip->ip_dst.s_addr)) { 213 if (!nortfree) 214 RTFREE(rte); 215 rte = ro->ro_rt = (struct rtentry *)NULL; 216 ro->ro_lle = (struct llentry *)NULL; 217 } 218 #ifdef IPFIREWALL_FORWARD 219 if (rte == NULL && fwd_tag == NULL) { 220 #else 221 if (rte == NULL) { 222 #endif 223 bzero(dst, sizeof(*dst)); 224 dst->sin_family = AF_INET; 225 dst->sin_len = sizeof(*dst); 226 dst->sin_addr = ip->ip_dst; 227 } 228 /* 229 * If routing to interface only, short circuit routing lookup. 230 * The use of an all-ones broadcast address implies this; an 231 * interface is specified by the broadcast address of an interface, 232 * or the destination address of a ptp interface. 233 */ 234 if (flags & IP_SENDONES) { 235 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst)))) == NULL && 236 (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL) { 237 IPSTAT_INC(ips_noroute); 238 error = ENETUNREACH; 239 goto bad; 240 } 241 ip->ip_dst.s_addr = INADDR_BROADCAST; 242 dst->sin_addr = ip->ip_dst; 243 ifp = ia->ia_ifp; 244 ip->ip_ttl = 1; 245 isbroadcast = 1; 246 } else if (flags & IP_ROUTETOIF) { 247 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL && 248 (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0))) == NULL) { 249 IPSTAT_INC(ips_noroute); 250 error = ENETUNREACH; 251 goto bad; 252 } 253 ifp = ia->ia_ifp; 254 ip->ip_ttl = 1; 255 isbroadcast = in_broadcast(dst->sin_addr, ifp); 256 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) && 257 imo != NULL && imo->imo_multicast_ifp != NULL) { 258 /* 259 * Bypass the normal routing lookup for multicast 260 * packets if the interface is specified. 261 */ 262 ifp = imo->imo_multicast_ifp; 263 IFP_TO_IA(ifp, ia); 264 isbroadcast = 0; /* fool gcc */ 265 } else { 266 /* 267 * We want to do any cloning requested by the link layer, 268 * as this is probably required in all cases for correct 269 * operation (as it is for ARP). 270 */ 271 if (rte == NULL) { 272 #ifdef RADIX_MPATH 273 rtalloc_mpath_fib(ro, 274 ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr), 275 inp ? inp->inp_inc.inc_fibnum : M_GETFIB(m)); 276 #else 277 in_rtalloc_ign(ro, 0, 278 inp ? inp->inp_inc.inc_fibnum : M_GETFIB(m)); 279 #endif 280 rte = ro->ro_rt; 281 } 282 if (rte == NULL || 283 rte->rt_ifp == NULL || 284 !RT_LINK_IS_UP(rte->rt_ifp)) { 285 #ifdef IPSEC 286 /* 287 * There is no route for this packet, but it is 288 * possible that a matching SPD entry exists. 289 */ 290 no_route_but_check_spd = 1; 291 mtu = 0; /* Silence GCC warning. */ 292 goto sendit; 293 #endif 294 IPSTAT_INC(ips_noroute); 295 error = EHOSTUNREACH; 296 goto bad; 297 } 298 ia = ifatoia(rte->rt_ifa); 299 ifa_ref(&ia->ia_ifa); 300 ifp = rte->rt_ifp; 301 rte->rt_rmx.rmx_pksent++; 302 if (rte->rt_flags & RTF_GATEWAY) 303 dst = (struct sockaddr_in *)rte->rt_gateway; 304 if (rte->rt_flags & RTF_HOST) 305 isbroadcast = (rte->rt_flags & RTF_BROADCAST); 306 else 307 isbroadcast = in_broadcast(dst->sin_addr, ifp); 308 } 309 /* 310 * Calculate MTU. If we have a route that is up, use that, 311 * otherwise use the interface's MTU. 312 */ 313 if (rte != NULL && (rte->rt_flags & (RTF_UP|RTF_HOST))) { 314 /* 315 * This case can happen if the user changed the MTU 316 * of an interface after enabling IP on it. Because 317 * most netifs don't keep track of routes pointing to 318 * them, there is no way for one to update all its 319 * routes when the MTU is changed. 320 */ 321 if (rte->rt_rmx.rmx_mtu > ifp->if_mtu) 322 rte->rt_rmx.rmx_mtu = ifp->if_mtu; 323 mtu = rte->rt_rmx.rmx_mtu; 324 } else { 325 mtu = ifp->if_mtu; 326 } 327 /* Catch a possible divide by zero later. */ 328 KASSERT(mtu > 0, ("%s: mtu %d <= 0, rte=%p (rt_flags=0x%08x) ifp=%p", 329 __func__, mtu, rte, (rte != NULL) ? rte->rt_flags : 0, ifp)); 330 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 331 m->m_flags |= M_MCAST; 332 /* 333 * IP destination address is multicast. Make sure "dst" 334 * still points to the address in "ro". (It may have been 335 * changed to point to a gateway address, above.) 336 */ 337 dst = (struct sockaddr_in *)&ro->ro_dst; 338 /* 339 * See if the caller provided any multicast options 340 */ 341 if (imo != NULL) { 342 ip->ip_ttl = imo->imo_multicast_ttl; 343 if (imo->imo_multicast_vif != -1) 344 ip->ip_src.s_addr = 345 ip_mcast_src ? 346 ip_mcast_src(imo->imo_multicast_vif) : 347 INADDR_ANY; 348 } else 349 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL; 350 /* 351 * Confirm that the outgoing interface supports multicast. 352 */ 353 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) { 354 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 355 IPSTAT_INC(ips_noroute); 356 error = ENETUNREACH; 357 goto bad; 358 } 359 } 360 /* 361 * If source address not specified yet, use address 362 * of outgoing interface. 363 */ 364 if (ip->ip_src.s_addr == INADDR_ANY) { 365 /* Interface may have no addresses. */ 366 if (ia != NULL) 367 ip->ip_src = IA_SIN(ia)->sin_addr; 368 } 369 370 if ((imo == NULL && in_mcast_loop) || 371 (imo && imo->imo_multicast_loop)) { 372 /* 373 * Loop back multicast datagram if not expressly 374 * forbidden to do so, even if we are not a member 375 * of the group; ip_input() will filter it later, 376 * thus deferring a hash lookup and mutex acquisition 377 * at the expense of a cheap copy using m_copym(). 378 */ 379 ip_mloopback(ifp, m, dst, hlen); 380 } else { 381 /* 382 * If we are acting as a multicast router, perform 383 * multicast forwarding as if the packet had just 384 * arrived on the interface to which we are about 385 * to send. The multicast forwarding function 386 * recursively calls this function, using the 387 * IP_FORWARDING flag to prevent infinite recursion. 388 * 389 * Multicasts that are looped back by ip_mloopback(), 390 * above, will be forwarded by the ip_input() routine, 391 * if necessary. 392 */ 393 if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) { 394 /* 395 * If rsvp daemon is not running, do not 396 * set ip_moptions. This ensures that the packet 397 * is multicast and not just sent down one link 398 * as prescribed by rsvpd. 399 */ 400 if (!V_rsvp_on) 401 imo = NULL; 402 if (ip_mforward && 403 ip_mforward(ip, ifp, m, imo) != 0) { 404 m_freem(m); 405 goto done; 406 } 407 } 408 } 409 410 /* 411 * Multicasts with a time-to-live of zero may be looped- 412 * back, above, but must not be transmitted on a network. 413 * Also, multicasts addressed to the loopback interface 414 * are not sent -- the above call to ip_mloopback() will 415 * loop back a copy. ip_input() will drop the copy if 416 * this host does not belong to the destination group on 417 * the loopback interface. 418 */ 419 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) { 420 m_freem(m); 421 goto done; 422 } 423 424 goto sendit; 425 } 426 427 /* 428 * If the source address is not specified yet, use the address 429 * of the outoing interface. 430 */ 431 if (ip->ip_src.s_addr == INADDR_ANY) { 432 /* Interface may have no addresses. */ 433 if (ia != NULL) { 434 ip->ip_src = IA_SIN(ia)->sin_addr; 435 } 436 } 437 438 /* 439 * Verify that we have any chance at all of being able to queue the 440 * packet or packet fragments, unless ALTQ is enabled on the given 441 * interface in which case packetdrop should be done by queueing. 442 */ 443 n = ip->ip_len / mtu + 1; /* how many fragments ? */ 444 if ( 445 #ifdef ALTQ 446 (!ALTQ_IS_ENABLED(&ifp->if_snd)) && 447 #endif /* ALTQ */ 448 (ifp->if_snd.ifq_len + n) >= ifp->if_snd.ifq_maxlen ) { 449 error = ENOBUFS; 450 IPSTAT_INC(ips_odropped); 451 ifp->if_snd.ifq_drops += n; 452 goto bad; 453 } 454 455 /* 456 * Look for broadcast address and 457 * verify user is allowed to send 458 * such a packet. 459 */ 460 if (isbroadcast) { 461 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 462 error = EADDRNOTAVAIL; 463 goto bad; 464 } 465 if ((flags & IP_ALLOWBROADCAST) == 0) { 466 error = EACCES; 467 goto bad; 468 } 469 /* don't allow broadcast messages to be fragmented */ 470 if (ip->ip_len > mtu) { 471 error = EMSGSIZE; 472 goto bad; 473 } 474 m->m_flags |= M_BCAST; 475 } else { 476 m->m_flags &= ~M_BCAST; 477 } 478 479 sendit: 480 #ifdef IPSEC 481 switch(ip_ipsec_output(&m, inp, &flags, &error)) { 482 case 1: 483 goto bad; 484 case -1: 485 goto done; 486 case 0: 487 default: 488 break; /* Continue with packet processing. */ 489 } 490 /* 491 * Check if there was a route for this packet; return error if not. 492 */ 493 if (no_route_but_check_spd) { 494 IPSTAT_INC(ips_noroute); 495 error = EHOSTUNREACH; 496 goto bad; 497 } 498 /* Update variables that are affected by ipsec4_output(). */ 499 ip = mtod(m, struct ip *); 500 hlen = ip->ip_hl << 2; 501 #endif /* IPSEC */ 502 503 /* Jump over all PFIL processing if hooks are not active. */ 504 if (!PFIL_HOOKED(&V_inet_pfil_hook)) 505 goto passout; 506 507 /* Run through list of hooks for output packets. */ 508 odst.s_addr = ip->ip_dst.s_addr; 509 error = pfil_run_hooks(&V_inet_pfil_hook, &m, ifp, PFIL_OUT, inp); 510 if (error != 0 || m == NULL) 511 goto done; 512 513 ip = mtod(m, struct ip *); 514 515 /* See if destination IP address was changed by packet filter. */ 516 if (odst.s_addr != ip->ip_dst.s_addr) { 517 m->m_flags |= M_SKIP_FIREWALL; 518 /* If destination is now ourself drop to ip_input(). */ 519 if (in_localip(ip->ip_dst)) { 520 m->m_flags |= M_FASTFWD_OURS; 521 if (m->m_pkthdr.rcvif == NULL) 522 m->m_pkthdr.rcvif = V_loif; 523 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 524 m->m_pkthdr.csum_flags |= 525 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 526 m->m_pkthdr.csum_data = 0xffff; 527 } 528 m->m_pkthdr.csum_flags |= 529 CSUM_IP_CHECKED | CSUM_IP_VALID; 530 #ifdef SCTP 531 if (m->m_pkthdr.csum_flags & CSUM_SCTP) 532 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID; 533 #endif 534 error = netisr_queue(NETISR_IP, m); 535 goto done; 536 } else { 537 if (ia != NULL) 538 ifa_free(&ia->ia_ifa); 539 goto again; /* Redo the routing table lookup. */ 540 } 541 } 542 543 #ifdef IPFIREWALL_FORWARD 544 /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */ 545 if (m->m_flags & M_FASTFWD_OURS) { 546 if (m->m_pkthdr.rcvif == NULL) 547 m->m_pkthdr.rcvif = V_loif; 548 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 549 m->m_pkthdr.csum_flags |= 550 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 551 m->m_pkthdr.csum_data = 0xffff; 552 } 553 #ifdef SCTP 554 if (m->m_pkthdr.csum_flags & CSUM_SCTP) 555 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID; 556 #endif 557 m->m_pkthdr.csum_flags |= 558 CSUM_IP_CHECKED | CSUM_IP_VALID; 559 560 error = netisr_queue(NETISR_IP, m); 561 goto done; 562 } 563 /* Or forward to some other address? */ 564 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL); 565 if (fwd_tag) { 566 dst = (struct sockaddr_in *)&ro->ro_dst; 567 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in)); 568 m->m_flags |= M_SKIP_FIREWALL; 569 m_tag_delete(m, fwd_tag); 570 if (ia != NULL) 571 ifa_free(&ia->ia_ifa); 572 goto again; 573 } 574 #endif /* IPFIREWALL_FORWARD */ 575 576 passout: 577 /* 127/8 must not appear on wire - RFC1122. */ 578 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 579 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 580 if ((ifp->if_flags & IFF_LOOPBACK) == 0) { 581 IPSTAT_INC(ips_badaddr); 582 error = EADDRNOTAVAIL; 583 goto bad; 584 } 585 } 586 587 m->m_pkthdr.csum_flags |= CSUM_IP; 588 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist; 589 if (sw_csum & CSUM_DELAY_DATA) { 590 in_delayed_cksum(m); 591 sw_csum &= ~CSUM_DELAY_DATA; 592 } 593 #ifdef SCTP 594 if (sw_csum & CSUM_SCTP) { 595 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2)); 596 sw_csum &= ~CSUM_SCTP; 597 } 598 #endif 599 m->m_pkthdr.csum_flags &= ifp->if_hwassist; 600 601 /* 602 * If small enough for interface, or the interface will take 603 * care of the fragmentation for us, we can just send directly. 604 */ 605 if (ip->ip_len <= mtu || 606 (m->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0 || 607 ((ip->ip_off & IP_DF) == 0 && (ifp->if_hwassist & CSUM_FRAGMENT))) { 608 ip->ip_len = htons(ip->ip_len); 609 ip->ip_off = htons(ip->ip_off); 610 ip->ip_sum = 0; 611 if (sw_csum & CSUM_DELAY_IP) 612 ip->ip_sum = in_cksum(m, hlen); 613 614 /* 615 * Record statistics for this interface address. 616 * With CSUM_TSO the byte/packet count will be slightly 617 * incorrect because we count the IP+TCP headers only 618 * once instead of for every generated packet. 619 */ 620 if (!(flags & IP_FORWARDING) && ia) { 621 if (m->m_pkthdr.csum_flags & CSUM_TSO) 622 ia->ia_ifa.if_opackets += 623 m->m_pkthdr.len / m->m_pkthdr.tso_segsz; 624 else 625 ia->ia_ifa.if_opackets++; 626 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 627 } 628 #ifdef MBUF_STRESS_TEST 629 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) 630 m = m_fragment(m, M_DONTWAIT, mbuf_frag_size); 631 #endif 632 /* 633 * Reset layer specific mbuf flags 634 * to avoid confusing lower layers. 635 */ 636 m->m_flags &= ~(M_PROTOFLAGS); 637 error = (*ifp->if_output)(ifp, m, 638 (struct sockaddr *)dst, ro); 639 goto done; 640 } 641 642 /* Balk when DF bit is set or the interface didn't support TSO. */ 643 if ((ip->ip_off & IP_DF) || (m->m_pkthdr.csum_flags & CSUM_TSO)) { 644 error = EMSGSIZE; 645 IPSTAT_INC(ips_cantfrag); 646 goto bad; 647 } 648 649 /* 650 * Too large for interface; fragment if possible. If successful, 651 * on return, m will point to a list of packets to be sent. 652 */ 653 error = ip_fragment(ip, &m, mtu, ifp->if_hwassist, sw_csum); 654 if (error) 655 goto bad; 656 for (; m; m = m0) { 657 m0 = m->m_nextpkt; 658 m->m_nextpkt = 0; 659 if (error == 0) { 660 /* Record statistics for this interface address. */ 661 if (ia != NULL) { 662 ia->ia_ifa.if_opackets++; 663 ia->ia_ifa.if_obytes += m->m_pkthdr.len; 664 } 665 /* 666 * Reset layer specific mbuf flags 667 * to avoid confusing upper layers. 668 */ 669 m->m_flags &= ~(M_PROTOFLAGS); 670 671 error = (*ifp->if_output)(ifp, m, 672 (struct sockaddr *)dst, ro); 673 } else 674 m_freem(m); 675 } 676 677 if (error == 0) 678 IPSTAT_INC(ips_fragmented); 679 680 done: 681 if (ro == &iproute && ro->ro_rt && !nortfree) { 682 RTFREE(ro->ro_rt); 683 } 684 if (ia != NULL) 685 ifa_free(&ia->ia_ifa); 686 return (error); 687 bad: 688 m_freem(m); 689 goto done; 690 } 691 692 /* 693 * Create a chain of fragments which fit the given mtu. m_frag points to the 694 * mbuf to be fragmented; on return it points to the chain with the fragments. 695 * Return 0 if no error. If error, m_frag may contain a partially built 696 * chain of fragments that should be freed by the caller. 697 * 698 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist) 699 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP). 700 */ 701 int 702 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu, 703 u_long if_hwassist_flags, int sw_csum) 704 { 705 int error = 0; 706 int hlen = ip->ip_hl << 2; 707 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */ 708 int off; 709 struct mbuf *m0 = *m_frag; /* the original packet */ 710 int firstlen; 711 struct mbuf **mnext; 712 int nfrags; 713 714 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */ 715 IPSTAT_INC(ips_cantfrag); 716 return EMSGSIZE; 717 } 718 719 /* 720 * Must be able to put at least 8 bytes per fragment. 721 */ 722 if (len < 8) 723 return EMSGSIZE; 724 725 /* 726 * If the interface will not calculate checksums on 727 * fragmented packets, then do it here. 728 */ 729 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA && 730 (if_hwassist_flags & CSUM_IP_FRAGS) == 0) { 731 in_delayed_cksum(m0); 732 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 733 } 734 #ifdef SCTP 735 if (m0->m_pkthdr.csum_flags & CSUM_SCTP && 736 (if_hwassist_flags & CSUM_IP_FRAGS) == 0) { 737 sctp_delayed_cksum(m0, hlen); 738 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP; 739 } 740 #endif 741 if (len > PAGE_SIZE) { 742 /* 743 * Fragment large datagrams such that each segment 744 * contains a multiple of PAGE_SIZE amount of data, 745 * plus headers. This enables a receiver to perform 746 * page-flipping zero-copy optimizations. 747 * 748 * XXX When does this help given that sender and receiver 749 * could have different page sizes, and also mtu could 750 * be less than the receiver's page size ? 751 */ 752 int newlen; 753 struct mbuf *m; 754 755 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next) 756 off += m->m_len; 757 758 /* 759 * firstlen (off - hlen) must be aligned on an 760 * 8-byte boundary 761 */ 762 if (off < hlen) 763 goto smart_frag_failure; 764 off = ((off - hlen) & ~7) + hlen; 765 newlen = (~PAGE_MASK) & mtu; 766 if ((newlen + sizeof (struct ip)) > mtu) { 767 /* we failed, go back the default */ 768 smart_frag_failure: 769 newlen = len; 770 off = hlen + len; 771 } 772 len = newlen; 773 774 } else { 775 off = hlen + len; 776 } 777 778 firstlen = off - hlen; 779 mnext = &m0->m_nextpkt; /* pointer to next packet */ 780 781 /* 782 * Loop through length of segment after first fragment, 783 * make new header and copy data of each part and link onto chain. 784 * Here, m0 is the original packet, m is the fragment being created. 785 * The fragments are linked off the m_nextpkt of the original 786 * packet, which after processing serves as the first fragment. 787 */ 788 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) { 789 struct ip *mhip; /* ip header on the fragment */ 790 struct mbuf *m; 791 int mhlen = sizeof (struct ip); 792 793 MGETHDR(m, M_DONTWAIT, MT_DATA); 794 if (m == NULL) { 795 error = ENOBUFS; 796 IPSTAT_INC(ips_odropped); 797 goto done; 798 } 799 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG; 800 /* 801 * In the first mbuf, leave room for the link header, then 802 * copy the original IP header including options. The payload 803 * goes into an additional mbuf chain returned by m_copym(). 804 */ 805 m->m_data += max_linkhdr; 806 mhip = mtod(m, struct ip *); 807 *mhip = *ip; 808 if (hlen > sizeof (struct ip)) { 809 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip); 810 mhip->ip_v = IPVERSION; 811 mhip->ip_hl = mhlen >> 2; 812 } 813 m->m_len = mhlen; 814 /* XXX do we need to add ip->ip_off below ? */ 815 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off; 816 if (off + len >= ip->ip_len) { /* last fragment */ 817 len = ip->ip_len - off; 818 m->m_flags |= M_LASTFRAG; 819 } else 820 mhip->ip_off |= IP_MF; 821 mhip->ip_len = htons((u_short)(len + mhlen)); 822 m->m_next = m_copym(m0, off, len, M_DONTWAIT); 823 if (m->m_next == NULL) { /* copy failed */ 824 m_free(m); 825 error = ENOBUFS; /* ??? */ 826 IPSTAT_INC(ips_odropped); 827 goto done; 828 } 829 m->m_pkthdr.len = mhlen + len; 830 m->m_pkthdr.rcvif = NULL; 831 #ifdef MAC 832 mac_netinet_fragment(m0, m); 833 #endif 834 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags; 835 mhip->ip_off = htons(mhip->ip_off); 836 mhip->ip_sum = 0; 837 if (sw_csum & CSUM_DELAY_IP) 838 mhip->ip_sum = in_cksum(m, mhlen); 839 *mnext = m; 840 mnext = &m->m_nextpkt; 841 } 842 IPSTAT_ADD(ips_ofragments, nfrags); 843 844 /* set first marker for fragment chain */ 845 m0->m_flags |= M_FIRSTFRAG | M_FRAG; 846 m0->m_pkthdr.csum_data = nfrags; 847 848 /* 849 * Update first fragment by trimming what's been copied out 850 * and updating header. 851 */ 852 m_adj(m0, hlen + firstlen - ip->ip_len); 853 m0->m_pkthdr.len = hlen + firstlen; 854 ip->ip_len = htons((u_short)m0->m_pkthdr.len); 855 ip->ip_off |= IP_MF; 856 ip->ip_off = htons(ip->ip_off); 857 ip->ip_sum = 0; 858 if (sw_csum & CSUM_DELAY_IP) 859 ip->ip_sum = in_cksum(m0, hlen); 860 861 done: 862 *m_frag = m0; 863 return error; 864 } 865 866 void 867 in_delayed_cksum(struct mbuf *m) 868 { 869 struct ip *ip; 870 u_short csum, offset; 871 872 ip = mtod(m, struct ip *); 873 offset = ip->ip_hl << 2 ; 874 csum = in_cksum_skip(m, ip->ip_len, offset); 875 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0) 876 csum = 0xffff; 877 offset += m->m_pkthdr.csum_data; /* checksum offset */ 878 879 if (offset + sizeof(u_short) > m->m_len) { 880 printf("delayed m_pullup, m->len: %d off: %d p: %d\n", 881 m->m_len, offset, ip->ip_p); 882 /* 883 * XXX 884 * this shouldn't happen, but if it does, the 885 * correct behavior may be to insert the checksum 886 * in the appropriate next mbuf in the chain. 887 */ 888 return; 889 } 890 *(u_short *)(m->m_data + offset) = csum; 891 } 892 893 /* 894 * IP socket option processing. 895 */ 896 int 897 ip_ctloutput(struct socket *so, struct sockopt *sopt) 898 { 899 struct inpcb *inp = sotoinpcb(so); 900 int error, optval; 901 902 error = optval = 0; 903 if (sopt->sopt_level != IPPROTO_IP) { 904 error = EINVAL; 905 906 if (sopt->sopt_level == SOL_SOCKET && 907 sopt->sopt_dir == SOPT_SET) { 908 switch (sopt->sopt_name) { 909 case SO_REUSEADDR: 910 INP_WLOCK(inp); 911 if (IN_MULTICAST(ntohl(inp->inp_laddr.s_addr))) { 912 if ((so->so_options & 913 (SO_REUSEADDR | SO_REUSEPORT)) != 0) 914 inp->inp_flags2 |= INP_REUSEPORT; 915 else 916 inp->inp_flags2 &= ~INP_REUSEPORT; 917 } 918 INP_WUNLOCK(inp); 919 error = 0; 920 break; 921 case SO_REUSEPORT: 922 INP_WLOCK(inp); 923 if ((so->so_options & SO_REUSEPORT) != 0) 924 inp->inp_flags2 |= INP_REUSEPORT; 925 else 926 inp->inp_flags2 &= ~INP_REUSEPORT; 927 INP_WUNLOCK(inp); 928 error = 0; 929 break; 930 case SO_SETFIB: 931 INP_WLOCK(inp); 932 inp->inp_inc.inc_fibnum = so->so_fibnum; 933 INP_WUNLOCK(inp); 934 error = 0; 935 break; 936 default: 937 break; 938 } 939 } 940 return (error); 941 } 942 943 switch (sopt->sopt_dir) { 944 case SOPT_SET: 945 switch (sopt->sopt_name) { 946 case IP_OPTIONS: 947 #ifdef notyet 948 case IP_RETOPTS: 949 #endif 950 { 951 struct mbuf *m; 952 if (sopt->sopt_valsize > MLEN) { 953 error = EMSGSIZE; 954 break; 955 } 956 MGET(m, sopt->sopt_td ? M_WAIT : M_DONTWAIT, MT_DATA); 957 if (m == NULL) { 958 error = ENOBUFS; 959 break; 960 } 961 m->m_len = sopt->sopt_valsize; 962 error = sooptcopyin(sopt, mtod(m, char *), m->m_len, 963 m->m_len); 964 if (error) { 965 m_free(m); 966 break; 967 } 968 INP_WLOCK(inp); 969 error = ip_pcbopts(inp, sopt->sopt_name, m); 970 INP_WUNLOCK(inp); 971 return (error); 972 } 973 974 case IP_BINDANY: 975 if (sopt->sopt_td != NULL) { 976 error = priv_check(sopt->sopt_td, 977 PRIV_NETINET_BINDANY); 978 if (error) 979 break; 980 } 981 /* FALLTHROUGH */ 982 case IP_TOS: 983 case IP_TTL: 984 case IP_MINTTL: 985 case IP_RECVOPTS: 986 case IP_RECVRETOPTS: 987 case IP_RECVDSTADDR: 988 case IP_RECVTTL: 989 case IP_RECVIF: 990 case IP_FAITH: 991 case IP_ONESBCAST: 992 case IP_DONTFRAG: 993 case IP_RECVTOS: 994 error = sooptcopyin(sopt, &optval, sizeof optval, 995 sizeof optval); 996 if (error) 997 break; 998 999 switch (sopt->sopt_name) { 1000 case IP_TOS: 1001 inp->inp_ip_tos = optval; 1002 break; 1003 1004 case IP_TTL: 1005 inp->inp_ip_ttl = optval; 1006 break; 1007 1008 case IP_MINTTL: 1009 if (optval >= 0 && optval <= MAXTTL) 1010 inp->inp_ip_minttl = optval; 1011 else 1012 error = EINVAL; 1013 break; 1014 1015 #define OPTSET(bit) do { \ 1016 INP_WLOCK(inp); \ 1017 if (optval) \ 1018 inp->inp_flags |= bit; \ 1019 else \ 1020 inp->inp_flags &= ~bit; \ 1021 INP_WUNLOCK(inp); \ 1022 } while (0) 1023 1024 case IP_RECVOPTS: 1025 OPTSET(INP_RECVOPTS); 1026 break; 1027 1028 case IP_RECVRETOPTS: 1029 OPTSET(INP_RECVRETOPTS); 1030 break; 1031 1032 case IP_RECVDSTADDR: 1033 OPTSET(INP_RECVDSTADDR); 1034 break; 1035 1036 case IP_RECVTTL: 1037 OPTSET(INP_RECVTTL); 1038 break; 1039 1040 case IP_RECVIF: 1041 OPTSET(INP_RECVIF); 1042 break; 1043 1044 case IP_FAITH: 1045 OPTSET(INP_FAITH); 1046 break; 1047 1048 case IP_ONESBCAST: 1049 OPTSET(INP_ONESBCAST); 1050 break; 1051 case IP_DONTFRAG: 1052 OPTSET(INP_DONTFRAG); 1053 break; 1054 case IP_BINDANY: 1055 OPTSET(INP_BINDANY); 1056 break; 1057 case IP_RECVTOS: 1058 OPTSET(INP_RECVTOS); 1059 break; 1060 } 1061 break; 1062 #undef OPTSET 1063 1064 /* 1065 * Multicast socket options are processed by the in_mcast 1066 * module. 1067 */ 1068 case IP_MULTICAST_IF: 1069 case IP_MULTICAST_VIF: 1070 case IP_MULTICAST_TTL: 1071 case IP_MULTICAST_LOOP: 1072 case IP_ADD_MEMBERSHIP: 1073 case IP_DROP_MEMBERSHIP: 1074 case IP_ADD_SOURCE_MEMBERSHIP: 1075 case IP_DROP_SOURCE_MEMBERSHIP: 1076 case IP_BLOCK_SOURCE: 1077 case IP_UNBLOCK_SOURCE: 1078 case IP_MSFILTER: 1079 case MCAST_JOIN_GROUP: 1080 case MCAST_LEAVE_GROUP: 1081 case MCAST_JOIN_SOURCE_GROUP: 1082 case MCAST_LEAVE_SOURCE_GROUP: 1083 case MCAST_BLOCK_SOURCE: 1084 case MCAST_UNBLOCK_SOURCE: 1085 error = inp_setmoptions(inp, sopt); 1086 break; 1087 1088 case IP_PORTRANGE: 1089 error = sooptcopyin(sopt, &optval, sizeof optval, 1090 sizeof optval); 1091 if (error) 1092 break; 1093 1094 INP_WLOCK(inp); 1095 switch (optval) { 1096 case IP_PORTRANGE_DEFAULT: 1097 inp->inp_flags &= ~(INP_LOWPORT); 1098 inp->inp_flags &= ~(INP_HIGHPORT); 1099 break; 1100 1101 case IP_PORTRANGE_HIGH: 1102 inp->inp_flags &= ~(INP_LOWPORT); 1103 inp->inp_flags |= INP_HIGHPORT; 1104 break; 1105 1106 case IP_PORTRANGE_LOW: 1107 inp->inp_flags &= ~(INP_HIGHPORT); 1108 inp->inp_flags |= INP_LOWPORT; 1109 break; 1110 1111 default: 1112 error = EINVAL; 1113 break; 1114 } 1115 INP_WUNLOCK(inp); 1116 break; 1117 1118 #ifdef IPSEC 1119 case IP_IPSEC_POLICY: 1120 { 1121 caddr_t req; 1122 struct mbuf *m; 1123 1124 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */ 1125 break; 1126 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */ 1127 break; 1128 req = mtod(m, caddr_t); 1129 error = ipsec_set_policy(inp, sopt->sopt_name, req, 1130 m->m_len, (sopt->sopt_td != NULL) ? 1131 sopt->sopt_td->td_ucred : NULL); 1132 m_freem(m); 1133 break; 1134 } 1135 #endif /* IPSEC */ 1136 1137 default: 1138 error = ENOPROTOOPT; 1139 break; 1140 } 1141 break; 1142 1143 case SOPT_GET: 1144 switch (sopt->sopt_name) { 1145 case IP_OPTIONS: 1146 case IP_RETOPTS: 1147 if (inp->inp_options) 1148 error = sooptcopyout(sopt, 1149 mtod(inp->inp_options, 1150 char *), 1151 inp->inp_options->m_len); 1152 else 1153 sopt->sopt_valsize = 0; 1154 break; 1155 1156 case IP_TOS: 1157 case IP_TTL: 1158 case IP_MINTTL: 1159 case IP_RECVOPTS: 1160 case IP_RECVRETOPTS: 1161 case IP_RECVDSTADDR: 1162 case IP_RECVTTL: 1163 case IP_RECVIF: 1164 case IP_PORTRANGE: 1165 case IP_FAITH: 1166 case IP_ONESBCAST: 1167 case IP_DONTFRAG: 1168 case IP_BINDANY: 1169 case IP_RECVTOS: 1170 switch (sopt->sopt_name) { 1171 1172 case IP_TOS: 1173 optval = inp->inp_ip_tos; 1174 break; 1175 1176 case IP_TTL: 1177 optval = inp->inp_ip_ttl; 1178 break; 1179 1180 case IP_MINTTL: 1181 optval = inp->inp_ip_minttl; 1182 break; 1183 1184 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0) 1185 1186 case IP_RECVOPTS: 1187 optval = OPTBIT(INP_RECVOPTS); 1188 break; 1189 1190 case IP_RECVRETOPTS: 1191 optval = OPTBIT(INP_RECVRETOPTS); 1192 break; 1193 1194 case IP_RECVDSTADDR: 1195 optval = OPTBIT(INP_RECVDSTADDR); 1196 break; 1197 1198 case IP_RECVTTL: 1199 optval = OPTBIT(INP_RECVTTL); 1200 break; 1201 1202 case IP_RECVIF: 1203 optval = OPTBIT(INP_RECVIF); 1204 break; 1205 1206 case IP_PORTRANGE: 1207 if (inp->inp_flags & INP_HIGHPORT) 1208 optval = IP_PORTRANGE_HIGH; 1209 else if (inp->inp_flags & INP_LOWPORT) 1210 optval = IP_PORTRANGE_LOW; 1211 else 1212 optval = 0; 1213 break; 1214 1215 case IP_FAITH: 1216 optval = OPTBIT(INP_FAITH); 1217 break; 1218 1219 case IP_ONESBCAST: 1220 optval = OPTBIT(INP_ONESBCAST); 1221 break; 1222 case IP_DONTFRAG: 1223 optval = OPTBIT(INP_DONTFRAG); 1224 break; 1225 case IP_BINDANY: 1226 optval = OPTBIT(INP_BINDANY); 1227 break; 1228 case IP_RECVTOS: 1229 optval = OPTBIT(INP_RECVTOS); 1230 break; 1231 } 1232 error = sooptcopyout(sopt, &optval, sizeof optval); 1233 break; 1234 1235 /* 1236 * Multicast socket options are processed by the in_mcast 1237 * module. 1238 */ 1239 case IP_MULTICAST_IF: 1240 case IP_MULTICAST_VIF: 1241 case IP_MULTICAST_TTL: 1242 case IP_MULTICAST_LOOP: 1243 case IP_MSFILTER: 1244 error = inp_getmoptions(inp, sopt); 1245 break; 1246 1247 #ifdef IPSEC 1248 case IP_IPSEC_POLICY: 1249 { 1250 struct mbuf *m = NULL; 1251 caddr_t req = NULL; 1252 size_t len = 0; 1253 1254 if (m != 0) { 1255 req = mtod(m, caddr_t); 1256 len = m->m_len; 1257 } 1258 error = ipsec_get_policy(sotoinpcb(so), req, len, &m); 1259 if (error == 0) 1260 error = soopt_mcopyout(sopt, m); /* XXX */ 1261 if (error == 0) 1262 m_freem(m); 1263 break; 1264 } 1265 #endif /* IPSEC */ 1266 1267 default: 1268 error = ENOPROTOOPT; 1269 break; 1270 } 1271 break; 1272 } 1273 return (error); 1274 } 1275 1276 /* 1277 * Routine called from ip_output() to loop back a copy of an IP multicast 1278 * packet to the input queue of a specified interface. Note that this 1279 * calls the output routine of the loopback "driver", but with an interface 1280 * pointer that might NOT be a loopback interface -- evil, but easier than 1281 * replicating that code here. 1282 */ 1283 static void 1284 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst, 1285 int hlen) 1286 { 1287 register struct ip *ip; 1288 struct mbuf *copym; 1289 1290 /* 1291 * Make a deep copy of the packet because we're going to 1292 * modify the pack in order to generate checksums. 1293 */ 1294 copym = m_dup(m, M_DONTWAIT); 1295 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen)) 1296 copym = m_pullup(copym, hlen); 1297 if (copym != NULL) { 1298 /* If needed, compute the checksum and mark it as valid. */ 1299 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 1300 in_delayed_cksum(copym); 1301 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 1302 copym->m_pkthdr.csum_flags |= 1303 CSUM_DATA_VALID | CSUM_PSEUDO_HDR; 1304 copym->m_pkthdr.csum_data = 0xffff; 1305 } 1306 /* 1307 * We don't bother to fragment if the IP length is greater 1308 * than the interface's MTU. Can this possibly matter? 1309 */ 1310 ip = mtod(copym, struct ip *); 1311 ip->ip_len = htons(ip->ip_len); 1312 ip->ip_off = htons(ip->ip_off); 1313 ip->ip_sum = 0; 1314 ip->ip_sum = in_cksum(copym, hlen); 1315 #if 1 /* XXX */ 1316 if (dst->sin_family != AF_INET) { 1317 printf("ip_mloopback: bad address family %d\n", 1318 dst->sin_family); 1319 dst->sin_family = AF_INET; 1320 } 1321 #endif 1322 if_simloop(ifp, copym, dst->sin_family, 0); 1323 } 1324 }
Cache object: a03ecd3255914c99cf08f873597f7d05
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