1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1988, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_bootp.h" 38 #include "opt_inet.h" 39 #include "opt_ipstealth.h" 40 #include "opt_ipsec.h" 41 #include "opt_route.h" 42 #include "opt_rss.h" 43 #include "opt_sctp.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/hhook.h> 48 #include <sys/mbuf.h> 49 #include <sys/malloc.h> 50 #include <sys/domain.h> 51 #include <sys/protosw.h> 52 #include <sys/socket.h> 53 #include <sys/time.h> 54 #include <sys/kernel.h> 55 #include <sys/lock.h> 56 #include <sys/rmlock.h> 57 #include <sys/rwlock.h> 58 #include <sys/sdt.h> 59 #include <sys/syslog.h> 60 #include <sys/sysctl.h> 61 62 #include <net/if.h> 63 #include <net/if_types.h> 64 #include <net/if_var.h> 65 #include <net/if_dl.h> 66 #include <net/if_private.h> 67 #include <net/pfil.h> 68 #include <net/route.h> 69 #include <net/route/nhop.h> 70 #include <net/netisr.h> 71 #include <net/rss_config.h> 72 #include <net/vnet.h> 73 74 #include <netinet/in.h> 75 #include <netinet/in_kdtrace.h> 76 #include <netinet/in_systm.h> 77 #include <netinet/in_var.h> 78 #include <netinet/ip.h> 79 #include <netinet/in_fib.h> 80 #include <netinet/in_pcb.h> 81 #include <netinet/ip_var.h> 82 #include <netinet/ip_encap.h> 83 #include <netinet/ip_fw.h> 84 #include <netinet/ip_icmp.h> 85 #include <netinet/igmp_var.h> 86 #include <netinet/ip_options.h> 87 #include <machine/in_cksum.h> 88 #include <netinet/ip_carp.h> 89 #include <netinet/in_rss.h> 90 #ifdef SCTP 91 #include <netinet/sctp_var.h> 92 #endif 93 94 #include <netipsec/ipsec_support.h> 95 96 #include <sys/socketvar.h> 97 98 #include <security/mac/mac_framework.h> 99 100 #ifdef CTASSERT 101 CTASSERT(sizeof(struct ip) == 20); 102 #endif 103 104 /* IP reassembly functions are defined in ip_reass.c. */ 105 extern void ipreass_init(void); 106 extern void ipreass_vnet_init(void); 107 #ifdef VIMAGE 108 extern void ipreass_destroy(void); 109 #endif 110 111 VNET_DEFINE(int, rsvp_on); 112 113 VNET_DEFINE(int, ipforwarding); 114 SYSCTL_INT(_net_inet_ip, IPCTL_FORWARDING, forwarding, CTLFLAG_VNET | CTLFLAG_RW, 115 &VNET_NAME(ipforwarding), 0, 116 "Enable IP forwarding between interfaces"); 117 118 /* 119 * Respond with an ICMP host redirect when we forward a packet out of 120 * the same interface on which it was received. See RFC 792. 121 */ 122 VNET_DEFINE(int, ipsendredirects) = 1; 123 SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect, CTLFLAG_VNET | CTLFLAG_RW, 124 &VNET_NAME(ipsendredirects), 0, 125 "Enable sending IP redirects"); 126 127 VNET_DEFINE_STATIC(bool, ip_strong_es) = false; 128 #define V_ip_strong_es VNET(ip_strong_es) 129 SYSCTL_BOOL(_net_inet_ip, OID_AUTO, rfc1122_strong_es, 130 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip_strong_es), false, 131 "Packet's IP destination address must match address on arrival interface"); 132 133 VNET_DEFINE_STATIC(bool, ip_sav) = true; 134 #define V_ip_sav VNET(ip_sav) 135 SYSCTL_BOOL(_net_inet_ip, OID_AUTO, source_address_validation, 136 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip_sav), true, 137 "Drop incoming packets with source address that is a local address"); 138 139 VNET_DEFINE(pfil_head_t, inet_pfil_head); /* Packet filter hooks */ 140 141 static struct netisr_handler ip_nh = { 142 .nh_name = "ip", 143 .nh_handler = ip_input, 144 .nh_proto = NETISR_IP, 145 #ifdef RSS 146 .nh_m2cpuid = rss_soft_m2cpuid_v4, 147 .nh_policy = NETISR_POLICY_CPU, 148 .nh_dispatch = NETISR_DISPATCH_HYBRID, 149 #else 150 .nh_policy = NETISR_POLICY_FLOW, 151 #endif 152 }; 153 154 #ifdef RSS 155 /* 156 * Directly dispatched frames are currently assumed 157 * to have a flowid already calculated. 158 * 159 * It should likely have something that assert it 160 * actually has valid flow details. 161 */ 162 static struct netisr_handler ip_direct_nh = { 163 .nh_name = "ip_direct", 164 .nh_handler = ip_direct_input, 165 .nh_proto = NETISR_IP_DIRECT, 166 .nh_m2cpuid = rss_soft_m2cpuid_v4, 167 .nh_policy = NETISR_POLICY_CPU, 168 .nh_dispatch = NETISR_DISPATCH_HYBRID, 169 }; 170 #endif 171 172 ipproto_input_t *ip_protox[IPPROTO_MAX] = { 173 [0 ... IPPROTO_MAX - 1] = rip_input }; 174 ipproto_ctlinput_t *ip_ctlprotox[IPPROTO_MAX] = { 175 [0 ... IPPROTO_MAX - 1] = rip_ctlinput }; 176 177 VNET_DEFINE(struct in_ifaddrhead, in_ifaddrhead); /* first inet address */ 178 VNET_DEFINE(struct in_ifaddrhashhead *, in_ifaddrhashtbl); /* inet addr hash table */ 179 VNET_DEFINE(u_long, in_ifaddrhmask); /* mask for hash table */ 180 181 /* Make sure it is safe to use hashinit(9) on CK_LIST. */ 182 CTASSERT(sizeof(struct in_ifaddrhashhead) == sizeof(LIST_HEAD(, in_addr))); 183 184 #ifdef IPCTL_DEFMTU 185 SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW, 186 &ip_mtu, 0, "Default MTU"); 187 #endif 188 189 #ifdef IPSTEALTH 190 VNET_DEFINE(int, ipstealth); 191 SYSCTL_INT(_net_inet_ip, OID_AUTO, stealth, CTLFLAG_VNET | CTLFLAG_RW, 192 &VNET_NAME(ipstealth), 0, 193 "IP stealth mode, no TTL decrementation on forwarding"); 194 #endif 195 196 /* 197 * IP statistics are stored in the "array" of counter(9)s. 198 */ 199 VNET_PCPUSTAT_DEFINE(struct ipstat, ipstat); 200 VNET_PCPUSTAT_SYSINIT(ipstat); 201 SYSCTL_VNET_PCPUSTAT(_net_inet_ip, IPCTL_STATS, stats, struct ipstat, ipstat, 202 "IP statistics (struct ipstat, netinet/ip_var.h)"); 203 204 #ifdef VIMAGE 205 VNET_PCPUSTAT_SYSUNINIT(ipstat); 206 #endif /* VIMAGE */ 207 208 /* 209 * Kernel module interface for updating ipstat. The argument is an index 210 * into ipstat treated as an array. 211 */ 212 void 213 kmod_ipstat_inc(int statnum) 214 { 215 216 counter_u64_add(VNET(ipstat)[statnum], 1); 217 } 218 219 void 220 kmod_ipstat_dec(int statnum) 221 { 222 223 counter_u64_add(VNET(ipstat)[statnum], -1); 224 } 225 226 static int 227 sysctl_netinet_intr_queue_maxlen(SYSCTL_HANDLER_ARGS) 228 { 229 int error, qlimit; 230 231 netisr_getqlimit(&ip_nh, &qlimit); 232 error = sysctl_handle_int(oidp, &qlimit, 0, req); 233 if (error || !req->newptr) 234 return (error); 235 if (qlimit < 1) 236 return (EINVAL); 237 return (netisr_setqlimit(&ip_nh, qlimit)); 238 } 239 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen, 240 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0, 241 sysctl_netinet_intr_queue_maxlen, "I", 242 "Maximum size of the IP input queue"); 243 244 static int 245 sysctl_netinet_intr_queue_drops(SYSCTL_HANDLER_ARGS) 246 { 247 u_int64_t qdrops_long; 248 int error, qdrops; 249 250 netisr_getqdrops(&ip_nh, &qdrops_long); 251 qdrops = qdrops_long; 252 error = sysctl_handle_int(oidp, &qdrops, 0, req); 253 if (error || !req->newptr) 254 return (error); 255 if (qdrops != 0) 256 return (EINVAL); 257 netisr_clearqdrops(&ip_nh); 258 return (0); 259 } 260 261 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops, 262 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, 263 0, 0, sysctl_netinet_intr_queue_drops, "I", 264 "Number of packets dropped from the IP input queue"); 265 266 #ifdef RSS 267 static int 268 sysctl_netinet_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS) 269 { 270 int error, qlimit; 271 272 netisr_getqlimit(&ip_direct_nh, &qlimit); 273 error = sysctl_handle_int(oidp, &qlimit, 0, req); 274 if (error || !req->newptr) 275 return (error); 276 if (qlimit < 1) 277 return (EINVAL); 278 return (netisr_setqlimit(&ip_direct_nh, qlimit)); 279 } 280 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRDQMAXLEN, intr_direct_queue_maxlen, 281 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 282 0, 0, sysctl_netinet_intr_direct_queue_maxlen, 283 "I", "Maximum size of the IP direct input queue"); 284 285 static int 286 sysctl_netinet_intr_direct_queue_drops(SYSCTL_HANDLER_ARGS) 287 { 288 u_int64_t qdrops_long; 289 int error, qdrops; 290 291 netisr_getqdrops(&ip_direct_nh, &qdrops_long); 292 qdrops = qdrops_long; 293 error = sysctl_handle_int(oidp, &qdrops, 0, req); 294 if (error || !req->newptr) 295 return (error); 296 if (qdrops != 0) 297 return (EINVAL); 298 netisr_clearqdrops(&ip_direct_nh); 299 return (0); 300 } 301 302 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRDQDROPS, intr_direct_queue_drops, 303 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0, 304 sysctl_netinet_intr_direct_queue_drops, "I", 305 "Number of packets dropped from the IP direct input queue"); 306 #endif /* RSS */ 307 308 /* 309 * IP initialization: fill in IP protocol switch table. 310 * All protocols not implemented in kernel go to raw IP protocol handler. 311 */ 312 static void 313 ip_vnet_init(void *arg __unused) 314 { 315 struct pfil_head_args args; 316 317 CK_STAILQ_INIT(&V_in_ifaddrhead); 318 V_in_ifaddrhashtbl = hashinit(INADDR_NHASH, M_IFADDR, &V_in_ifaddrhmask); 319 320 /* Initialize IP reassembly queue. */ 321 ipreass_vnet_init(); 322 323 /* Initialize packet filter hooks. */ 324 args.pa_version = PFIL_VERSION; 325 args.pa_flags = PFIL_IN | PFIL_OUT; 326 args.pa_type = PFIL_TYPE_IP4; 327 args.pa_headname = PFIL_INET_NAME; 328 V_inet_pfil_head = pfil_head_register(&args); 329 330 if (hhook_head_register(HHOOK_TYPE_IPSEC_IN, AF_INET, 331 &V_ipsec_hhh_in[HHOOK_IPSEC_INET], 332 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 333 printf("%s: WARNING: unable to register input helper hook\n", 334 __func__); 335 if (hhook_head_register(HHOOK_TYPE_IPSEC_OUT, AF_INET, 336 &V_ipsec_hhh_out[HHOOK_IPSEC_INET], 337 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0) 338 printf("%s: WARNING: unable to register output helper hook\n", 339 __func__); 340 341 #ifdef VIMAGE 342 netisr_register_vnet(&ip_nh); 343 #ifdef RSS 344 netisr_register_vnet(&ip_direct_nh); 345 #endif 346 #endif 347 } 348 VNET_SYSINIT(ip_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, 349 ip_vnet_init, NULL); 350 351 static void 352 ip_init(const void *unused __unused) 353 { 354 355 ipreass_init(); 356 357 /* 358 * Register statically compiled protocols, that are unlikely to 359 * ever become dynamic. 360 */ 361 IPPROTO_REGISTER(IPPROTO_ICMP, icmp_input, NULL); 362 IPPROTO_REGISTER(IPPROTO_IGMP, igmp_input, NULL); 363 IPPROTO_REGISTER(IPPROTO_RSVP, rsvp_input, NULL); 364 IPPROTO_REGISTER(IPPROTO_IPV4, encap4_input, NULL); 365 IPPROTO_REGISTER(IPPROTO_MOBILE, encap4_input, NULL); 366 IPPROTO_REGISTER(IPPROTO_ETHERIP, encap4_input, NULL); 367 IPPROTO_REGISTER(IPPROTO_GRE, encap4_input, NULL); 368 IPPROTO_REGISTER(IPPROTO_IPV6, encap4_input, NULL); 369 IPPROTO_REGISTER(IPPROTO_PIM, encap4_input, NULL); 370 #ifdef SCTP /* XXX: has a loadable & static version */ 371 IPPROTO_REGISTER(IPPROTO_SCTP, sctp_input, sctp_ctlinput); 372 #endif 373 374 netisr_register(&ip_nh); 375 #ifdef RSS 376 netisr_register(&ip_direct_nh); 377 #endif 378 } 379 SYSINIT(ip_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip_init, NULL); 380 381 #ifdef VIMAGE 382 static void 383 ip_destroy(void *unused __unused) 384 { 385 int error; 386 387 #ifdef RSS 388 netisr_unregister_vnet(&ip_direct_nh); 389 #endif 390 netisr_unregister_vnet(&ip_nh); 391 392 pfil_head_unregister(V_inet_pfil_head); 393 error = hhook_head_deregister(V_ipsec_hhh_in[HHOOK_IPSEC_INET]); 394 if (error != 0) { 395 printf("%s: WARNING: unable to deregister input helper hook " 396 "type HHOOK_TYPE_IPSEC_IN, id HHOOK_IPSEC_INET: " 397 "error %d returned\n", __func__, error); 398 } 399 error = hhook_head_deregister(V_ipsec_hhh_out[HHOOK_IPSEC_INET]); 400 if (error != 0) { 401 printf("%s: WARNING: unable to deregister output helper hook " 402 "type HHOOK_TYPE_IPSEC_OUT, id HHOOK_IPSEC_INET: " 403 "error %d returned\n", __func__, error); 404 } 405 406 /* Remove the IPv4 addresses from all interfaces. */ 407 in_ifscrub_all(); 408 409 /* Make sure the IPv4 routes are gone as well. */ 410 rib_flush_routes_family(AF_INET); 411 412 /* Destroy IP reassembly queue. */ 413 ipreass_destroy(); 414 415 /* Cleanup in_ifaddr hash table; should be empty. */ 416 hashdestroy(V_in_ifaddrhashtbl, M_IFADDR, V_in_ifaddrhmask); 417 } 418 419 VNET_SYSUNINIT(ip, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip_destroy, NULL); 420 #endif 421 422 #ifdef RSS 423 /* 424 * IP direct input routine. 425 * 426 * This is called when reinjecting completed fragments where 427 * all of the previous checking and book-keeping has been done. 428 */ 429 void 430 ip_direct_input(struct mbuf *m) 431 { 432 struct ip *ip; 433 int hlen; 434 435 ip = mtod(m, struct ip *); 436 hlen = ip->ip_hl << 2; 437 438 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 439 if (IPSEC_ENABLED(ipv4)) { 440 if (IPSEC_INPUT(ipv4, m, hlen, ip->ip_p) != 0) 441 return; 442 } 443 #endif /* IPSEC */ 444 IPSTAT_INC(ips_delivered); 445 ip_protox[ip->ip_p](&m, &hlen, ip->ip_p); 446 } 447 #endif 448 449 /* 450 * Ip input routine. Checksum and byte swap header. If fragmented 451 * try to reassemble. Process options. Pass to next level. 452 */ 453 void 454 ip_input(struct mbuf *m) 455 { 456 struct ip *ip = NULL; 457 struct in_ifaddr *ia = NULL; 458 struct ifaddr *ifa; 459 struct ifnet *ifp; 460 int hlen = 0; 461 uint16_t sum, ip_len; 462 int dchg = 0; /* dest changed after fw */ 463 struct in_addr odst; /* original dst address */ 464 bool strong_es; 465 466 M_ASSERTPKTHDR(m); 467 NET_EPOCH_ASSERT(); 468 469 if (m->m_flags & M_FASTFWD_OURS) { 470 m->m_flags &= ~M_FASTFWD_OURS; 471 /* Set up some basics that will be used later. */ 472 ip = mtod(m, struct ip *); 473 hlen = ip->ip_hl << 2; 474 ip_len = ntohs(ip->ip_len); 475 goto ours; 476 } 477 478 IPSTAT_INC(ips_total); 479 480 if (__predict_false(m->m_pkthdr.len < sizeof(struct ip))) 481 goto tooshort; 482 483 if (m->m_len < sizeof(struct ip)) { 484 m = m_pullup(m, sizeof(struct ip)); 485 if (__predict_false(m == NULL)) { 486 IPSTAT_INC(ips_toosmall); 487 return; 488 } 489 } 490 ip = mtod(m, struct ip *); 491 492 if (__predict_false(ip->ip_v != IPVERSION)) { 493 IPSTAT_INC(ips_badvers); 494 goto bad; 495 } 496 497 hlen = ip->ip_hl << 2; 498 if (__predict_false(hlen < sizeof(struct ip))) { /* minimum header length */ 499 IPSTAT_INC(ips_badhlen); 500 goto bad; 501 } 502 if (hlen > m->m_len) { 503 m = m_pullup(m, hlen); 504 if (__predict_false(m == NULL)) { 505 IPSTAT_INC(ips_badhlen); 506 return; 507 } 508 ip = mtod(m, struct ip *); 509 } 510 511 IP_PROBE(receive, NULL, NULL, ip, m->m_pkthdr.rcvif, ip, NULL); 512 513 /* IN_LOOPBACK must not appear on the wire - RFC1122 */ 514 ifp = m->m_pkthdr.rcvif; 515 if (IN_LOOPBACK(ntohl(ip->ip_dst.s_addr)) || 516 IN_LOOPBACK(ntohl(ip->ip_src.s_addr))) { 517 if ((ifp->if_flags & IFF_LOOPBACK) == 0) { 518 IPSTAT_INC(ips_badaddr); 519 goto bad; 520 } 521 } 522 /* The unspecified address can appear only as a src address - RFC1122 */ 523 if (__predict_false(ntohl(ip->ip_dst.s_addr) == INADDR_ANY)) { 524 IPSTAT_INC(ips_badaddr); 525 goto bad; 526 } 527 528 if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) { 529 sum = !(m->m_pkthdr.csum_flags & CSUM_IP_VALID); 530 } else { 531 if (hlen == sizeof(struct ip)) { 532 sum = in_cksum_hdr(ip); 533 } else { 534 sum = in_cksum(m, hlen); 535 } 536 } 537 if (__predict_false(sum)) { 538 IPSTAT_INC(ips_badsum); 539 goto bad; 540 } 541 542 ip_len = ntohs(ip->ip_len); 543 if (__predict_false(ip_len < hlen)) { 544 IPSTAT_INC(ips_badlen); 545 goto bad; 546 } 547 548 /* 549 * Check that the amount of data in the buffers 550 * is as at least much as the IP header would have us expect. 551 * Trim mbufs if longer than we expect. 552 * Drop packet if shorter than we expect. 553 */ 554 if (__predict_false(m->m_pkthdr.len < ip_len)) { 555 tooshort: 556 IPSTAT_INC(ips_tooshort); 557 goto bad; 558 } 559 if (m->m_pkthdr.len > ip_len) { 560 if (m->m_len == m->m_pkthdr.len) { 561 m->m_len = ip_len; 562 m->m_pkthdr.len = ip_len; 563 } else 564 m_adj(m, ip_len - m->m_pkthdr.len); 565 } 566 567 /* 568 * Try to forward the packet, but if we fail continue. 569 * ip_tryforward() may generate redirects these days. 570 * XXX the logic below falling through to normal processing 571 * if redirects are required should be revisited as well. 572 * ip_tryforward() does inbound and outbound packet firewall 573 * processing. If firewall has decided that destination becomes 574 * our local address, it sets M_FASTFWD_OURS flag. In this 575 * case skip another inbound firewall processing and update 576 * ip pointer. 577 */ 578 if (V_ipforwarding != 0 579 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 580 && (!IPSEC_ENABLED(ipv4) || 581 IPSEC_CAPS(ipv4, m, IPSEC_CAP_OPERABLE) == 0) 582 #endif 583 ) { 584 /* 585 * ip_dooptions() was run so we can ignore the source route (or 586 * any IP options case) case for redirects in ip_tryforward(). 587 */ 588 if ((m = ip_tryforward(m)) == NULL) 589 return; 590 if (m->m_flags & M_FASTFWD_OURS) { 591 m->m_flags &= ~M_FASTFWD_OURS; 592 ip = mtod(m, struct ip *); 593 goto ours; 594 } 595 } 596 597 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 598 /* 599 * Bypass packet filtering for packets previously handled by IPsec. 600 */ 601 if (IPSEC_ENABLED(ipv4) && 602 IPSEC_CAPS(ipv4, m, IPSEC_CAP_BYPASS_FILTER) != 0) 603 goto passin; 604 #endif 605 606 /* 607 * Run through list of hooks for input packets. 608 * 609 * NB: Beware of the destination address changing (e.g. 610 * by NAT rewriting). When this happens, tell 611 * ip_forward to do the right thing. 612 */ 613 614 /* Jump over all PFIL processing if hooks are not active. */ 615 if (!PFIL_HOOKED_IN(V_inet_pfil_head)) 616 goto passin; 617 618 odst = ip->ip_dst; 619 if (pfil_mbuf_in(V_inet_pfil_head, &m, ifp, NULL) != 620 PFIL_PASS) 621 return; 622 if (m == NULL) /* consumed by filter */ 623 return; 624 625 ip = mtod(m, struct ip *); 626 dchg = (odst.s_addr != ip->ip_dst.s_addr); 627 628 if (m->m_flags & M_FASTFWD_OURS) { 629 m->m_flags &= ~M_FASTFWD_OURS; 630 goto ours; 631 } 632 if (m->m_flags & M_IP_NEXTHOP) { 633 if (m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) { 634 /* 635 * Directly ship the packet on. This allows 636 * forwarding packets originally destined to us 637 * to some other directly connected host. 638 */ 639 ip_forward(m, 1); 640 return; 641 } 642 } 643 passin: 644 645 /* 646 * Process options and, if not destined for us, 647 * ship it on. ip_dooptions returns 1 when an 648 * error was detected (causing an icmp message 649 * to be sent and the original packet to be freed). 650 */ 651 if (hlen > sizeof (struct ip) && ip_dooptions(m, 0)) 652 return; 653 654 /* greedy RSVP, snatches any PATH packet of the RSVP protocol and no 655 * matter if it is destined to another node, or whether it is 656 * a multicast one, RSVP wants it! and prevents it from being forwarded 657 * anywhere else. Also checks if the rsvp daemon is running before 658 * grabbing the packet. 659 */ 660 if (ip->ip_p == IPPROTO_RSVP && V_rsvp_on) 661 goto ours; 662 663 /* 664 * Check our list of addresses, to see if the packet is for us. 665 * If we don't have any addresses, assume any unicast packet 666 * we receive might be for us (and let the upper layers deal 667 * with it). 668 */ 669 if (CK_STAILQ_EMPTY(&V_in_ifaddrhead) && 670 (m->m_flags & (M_MCAST|M_BCAST)) == 0) 671 goto ours; 672 673 /* 674 * Enable a consistency check between the destination address 675 * and the arrival interface for a unicast packet (the RFC 1122 676 * strong ES model) with a list of additional predicates: 677 * - if IP forwarding is disabled 678 * - the packet is not locally generated 679 * - the packet is not subject to 'ipfw fwd' 680 * - Interface is not running CARP. If the packet got here, we already 681 * checked it with carp_iamatch() and carp_forus(). 682 */ 683 strong_es = V_ip_strong_es && (V_ipforwarding == 0) && 684 ((ifp->if_flags & IFF_LOOPBACK) == 0) && 685 ifp->if_carp == NULL && (dchg == 0); 686 687 /* 688 * Check for exact addresses in the hash bucket. 689 */ 690 CK_LIST_FOREACH(ia, INADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 691 if (IA_SIN(ia)->sin_addr.s_addr != ip->ip_dst.s_addr) 692 continue; 693 694 /* 695 * net.inet.ip.rfc1122_strong_es: the address matches, verify 696 * that the packet arrived via the correct interface. 697 */ 698 if (__predict_false(strong_es && ia->ia_ifp != ifp)) { 699 IPSTAT_INC(ips_badaddr); 700 goto bad; 701 } 702 703 /* 704 * net.inet.ip.source_address_validation: drop incoming 705 * packets that pretend to be ours. 706 */ 707 if (V_ip_sav && !(ifp->if_flags & IFF_LOOPBACK) && 708 __predict_false(in_localip_fib(ip->ip_src, ifp->if_fib))) { 709 IPSTAT_INC(ips_badaddr); 710 goto bad; 711 } 712 713 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1); 714 counter_u64_add(ia->ia_ifa.ifa_ibytes, m->m_pkthdr.len); 715 goto ours; 716 } 717 718 /* 719 * Check for broadcast addresses. 720 * 721 * Only accept broadcast packets that arrive via the matching 722 * interface. Reception of forwarded directed broadcasts would 723 * be handled via ip_forward() and ether_output() with the loopback 724 * into the stack for SIMPLEX interfaces handled by ether_output(). 725 */ 726 if (ifp->if_flags & IFF_BROADCAST) { 727 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 728 if (ifa->ifa_addr->sa_family != AF_INET) 729 continue; 730 ia = ifatoia(ifa); 731 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr == 732 ip->ip_dst.s_addr) { 733 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1); 734 counter_u64_add(ia->ia_ifa.ifa_ibytes, 735 m->m_pkthdr.len); 736 goto ours; 737 } 738 #ifdef BOOTP_COMPAT 739 if (IA_SIN(ia)->sin_addr.s_addr == INADDR_ANY) { 740 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1); 741 counter_u64_add(ia->ia_ifa.ifa_ibytes, 742 m->m_pkthdr.len); 743 goto ours; 744 } 745 #endif 746 } 747 ia = NULL; 748 } 749 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 750 /* 751 * RFC 3927 2.7: Do not forward multicast packets from 752 * IN_LINKLOCAL. 753 */ 754 if (V_ip_mrouter && !IN_LINKLOCAL(ntohl(ip->ip_src.s_addr))) { 755 /* 756 * If we are acting as a multicast router, all 757 * incoming multicast packets are passed to the 758 * kernel-level multicast forwarding function. 759 * The packet is returned (relatively) intact; if 760 * ip_mforward() returns a non-zero value, the packet 761 * must be discarded, else it may be accepted below. 762 */ 763 if (ip_mforward && ip_mforward(ip, ifp, m, 0) != 0) { 764 IPSTAT_INC(ips_cantforward); 765 m_freem(m); 766 return; 767 } 768 769 /* 770 * The process-level routing daemon needs to receive 771 * all multicast IGMP packets, whether or not this 772 * host belongs to their destination groups. 773 */ 774 if (ip->ip_p == IPPROTO_IGMP) { 775 goto ours; 776 } 777 IPSTAT_INC(ips_forward); 778 } 779 /* 780 * Assume the packet is for us, to avoid prematurely taking 781 * a lock on the in_multi hash. Protocols must perform 782 * their own filtering and update statistics accordingly. 783 */ 784 goto ours; 785 } 786 if (ip->ip_dst.s_addr == (u_long)INADDR_BROADCAST) 787 goto ours; 788 if (ip->ip_dst.s_addr == INADDR_ANY) 789 goto ours; 790 /* RFC 3927 2.7: Do not forward packets to or from IN_LINKLOCAL. */ 791 if (IN_LINKLOCAL(ntohl(ip->ip_dst.s_addr)) || 792 IN_LINKLOCAL(ntohl(ip->ip_src.s_addr))) { 793 IPSTAT_INC(ips_cantforward); 794 m_freem(m); 795 return; 796 } 797 798 /* 799 * Not for us; forward if possible and desirable. 800 */ 801 if (V_ipforwarding == 0) { 802 IPSTAT_INC(ips_cantforward); 803 m_freem(m); 804 } else { 805 ip_forward(m, dchg); 806 } 807 return; 808 809 ours: 810 #ifdef IPSTEALTH 811 /* 812 * IPSTEALTH: Process non-routing options only 813 * if the packet is destined for us. 814 */ 815 if (V_ipstealth && hlen > sizeof (struct ip) && ip_dooptions(m, 1)) 816 return; 817 #endif /* IPSTEALTH */ 818 819 /* 820 * Attempt reassembly; if it succeeds, proceed. 821 * ip_reass() will return a different mbuf. 822 */ 823 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) { 824 /* XXXGL: shouldn't we save & set m_flags? */ 825 m = ip_reass(m); 826 if (m == NULL) 827 return; 828 ip = mtod(m, struct ip *); 829 /* Get the header length of the reassembled packet */ 830 hlen = ip->ip_hl << 2; 831 } 832 833 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 834 if (IPSEC_ENABLED(ipv4)) { 835 if (IPSEC_INPUT(ipv4, m, hlen, ip->ip_p) != 0) 836 return; 837 } 838 #endif /* IPSEC */ 839 840 /* 841 * Switch out to protocol's input routine. 842 */ 843 IPSTAT_INC(ips_delivered); 844 845 ip_protox[ip->ip_p](&m, &hlen, ip->ip_p); 846 return; 847 bad: 848 m_freem(m); 849 } 850 851 int 852 ipproto_register(uint8_t proto, ipproto_input_t input, ipproto_ctlinput_t ctl) 853 { 854 855 MPASS(proto > 0); 856 857 /* 858 * The protocol slot must not be occupied by another protocol 859 * already. An index pointing to rip_input() is unused. 860 */ 861 if (ip_protox[proto] == rip_input) { 862 ip_protox[proto] = input; 863 ip_ctlprotox[proto] = ctl; 864 return (0); 865 } else 866 return (EEXIST); 867 } 868 869 int 870 ipproto_unregister(uint8_t proto) 871 { 872 873 MPASS(proto > 0); 874 875 if (ip_protox[proto] != rip_input) { 876 ip_protox[proto] = rip_input; 877 ip_ctlprotox[proto] = rip_ctlinput; 878 return (0); 879 } else 880 return (ENOENT); 881 } 882 883 /* 884 * Forward a packet. If some error occurs return the sender 885 * an icmp packet. Note we can't always generate a meaningful 886 * icmp message because icmp doesn't have a large enough repertoire 887 * of codes and types. 888 * 889 * If not forwarding, just drop the packet. This could be confusing 890 * if ipforwarding was zero but some routing protocol was advancing 891 * us as a gateway to somewhere. However, we must let the routing 892 * protocol deal with that. 893 * 894 * The srcrt parameter indicates whether the packet is being forwarded 895 * via a source route. 896 */ 897 void 898 ip_forward(struct mbuf *m, int srcrt) 899 { 900 struct ip *ip = mtod(m, struct ip *); 901 struct in_ifaddr *ia; 902 struct mbuf *mcopy; 903 struct sockaddr_in *sin; 904 struct in_addr dest; 905 struct route ro; 906 uint32_t flowid; 907 int error, type = 0, code = 0, mtu = 0; 908 909 NET_EPOCH_ASSERT(); 910 911 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 912 IPSTAT_INC(ips_cantforward); 913 m_freem(m); 914 return; 915 } 916 if ( 917 #ifdef IPSTEALTH 918 V_ipstealth == 0 && 919 #endif 920 ip->ip_ttl <= IPTTLDEC) { 921 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, 0, 0); 922 return; 923 } 924 925 bzero(&ro, sizeof(ro)); 926 sin = (struct sockaddr_in *)&ro.ro_dst; 927 sin->sin_family = AF_INET; 928 sin->sin_len = sizeof(*sin); 929 sin->sin_addr = ip->ip_dst; 930 flowid = m->m_pkthdr.flowid; 931 ro.ro_nh = fib4_lookup(M_GETFIB(m), ip->ip_dst, 0, NHR_REF, flowid); 932 if (ro.ro_nh != NULL) { 933 ia = ifatoia(ro.ro_nh->nh_ifa); 934 } else 935 ia = NULL; 936 /* 937 * Save the IP header and at most 8 bytes of the payload, 938 * in case we need to generate an ICMP message to the src. 939 * 940 * XXX this can be optimized a lot by saving the data in a local 941 * buffer on the stack (72 bytes at most), and only allocating the 942 * mbuf if really necessary. The vast majority of the packets 943 * are forwarded without having to send an ICMP back (either 944 * because unnecessary, or because rate limited), so we are 945 * really we are wasting a lot of work here. 946 * 947 * We don't use m_copym() because it might return a reference 948 * to a shared cluster. Both this function and ip_output() 949 * assume exclusive access to the IP header in `m', so any 950 * data in a cluster may change before we reach icmp_error(). 951 */ 952 mcopy = m_gethdr(M_NOWAIT, m->m_type); 953 if (mcopy != NULL && !m_dup_pkthdr(mcopy, m, M_NOWAIT)) { 954 /* 955 * It's probably ok if the pkthdr dup fails (because 956 * the deep copy of the tag chain failed), but for now 957 * be conservative and just discard the copy since 958 * code below may some day want the tags. 959 */ 960 m_free(mcopy); 961 mcopy = NULL; 962 } 963 if (mcopy != NULL) { 964 mcopy->m_len = min(ntohs(ip->ip_len), M_TRAILINGSPACE(mcopy)); 965 mcopy->m_pkthdr.len = mcopy->m_len; 966 m_copydata(m, 0, mcopy->m_len, mtod(mcopy, caddr_t)); 967 } 968 #ifdef IPSTEALTH 969 if (V_ipstealth == 0) 970 #endif 971 ip->ip_ttl -= IPTTLDEC; 972 #if defined(IPSEC) || defined(IPSEC_SUPPORT) 973 if (IPSEC_ENABLED(ipv4)) { 974 if ((error = IPSEC_FORWARD(ipv4, m)) != 0) { 975 /* mbuf consumed by IPsec */ 976 RO_NHFREE(&ro); 977 m_freem(mcopy); 978 if (error != EINPROGRESS) 979 IPSTAT_INC(ips_cantforward); 980 return; 981 } 982 /* No IPsec processing required */ 983 } 984 #endif /* IPSEC */ 985 /* 986 * If forwarding packet using same interface that it came in on, 987 * perhaps should send a redirect to sender to shortcut a hop. 988 * Only send redirect if source is sending directly to us, 989 * and if packet was not source routed (or has any options). 990 * Also, don't send redirect if forwarding using a default route 991 * or a route modified by a redirect. 992 */ 993 dest.s_addr = 0; 994 if (!srcrt && V_ipsendredirects && 995 ia != NULL && ia->ia_ifp == m->m_pkthdr.rcvif) { 996 struct nhop_object *nh; 997 998 nh = ro.ro_nh; 999 1000 if (nh != NULL && ((nh->nh_flags & (NHF_REDIRECT|NHF_DEFAULT)) == 0)) { 1001 struct in_ifaddr *nh_ia = (struct in_ifaddr *)(nh->nh_ifa); 1002 u_long src = ntohl(ip->ip_src.s_addr); 1003 1004 if (nh_ia != NULL && 1005 (src & nh_ia->ia_subnetmask) == nh_ia->ia_subnet) { 1006 /* Router requirements says to only send host redirects */ 1007 type = ICMP_REDIRECT; 1008 code = ICMP_REDIRECT_HOST; 1009 if (nh->nh_flags & NHF_GATEWAY) { 1010 if (nh->gw_sa.sa_family == AF_INET) 1011 dest.s_addr = nh->gw4_sa.sin_addr.s_addr; 1012 else /* Do not redirect in case gw is AF_INET6 */ 1013 type = 0; 1014 } else 1015 dest.s_addr = ip->ip_dst.s_addr; 1016 } 1017 } 1018 } 1019 1020 error = ip_output(m, NULL, &ro, IP_FORWARDING, NULL, NULL); 1021 1022 if (error == EMSGSIZE && ro.ro_nh) 1023 mtu = ro.ro_nh->nh_mtu; 1024 RO_NHFREE(&ro); 1025 1026 if (error) 1027 IPSTAT_INC(ips_cantforward); 1028 else { 1029 IPSTAT_INC(ips_forward); 1030 if (type) 1031 IPSTAT_INC(ips_redirectsent); 1032 else { 1033 if (mcopy) 1034 m_freem(mcopy); 1035 return; 1036 } 1037 } 1038 if (mcopy == NULL) 1039 return; 1040 1041 switch (error) { 1042 case 0: /* forwarded, but need redirect */ 1043 /* type, code set above */ 1044 break; 1045 1046 case ENETUNREACH: 1047 case EHOSTUNREACH: 1048 case ENETDOWN: 1049 case EHOSTDOWN: 1050 default: 1051 type = ICMP_UNREACH; 1052 code = ICMP_UNREACH_HOST; 1053 break; 1054 1055 case EMSGSIZE: 1056 type = ICMP_UNREACH; 1057 code = ICMP_UNREACH_NEEDFRAG; 1058 /* 1059 * If the MTU was set before make sure we are below the 1060 * interface MTU. 1061 * If the MTU wasn't set before use the interface mtu or 1062 * fall back to the next smaller mtu step compared to the 1063 * current packet size. 1064 */ 1065 if (mtu != 0) { 1066 if (ia != NULL) 1067 mtu = min(mtu, ia->ia_ifp->if_mtu); 1068 } else { 1069 if (ia != NULL) 1070 mtu = ia->ia_ifp->if_mtu; 1071 else 1072 mtu = ip_next_mtu(ntohs(ip->ip_len), 0); 1073 } 1074 IPSTAT_INC(ips_cantfrag); 1075 break; 1076 1077 case ENOBUFS: 1078 case EACCES: /* ipfw denied packet */ 1079 m_freem(mcopy); 1080 return; 1081 } 1082 icmp_error(mcopy, type, code, dest.s_addr, mtu); 1083 } 1084 1085 #define CHECK_SO_CT(sp, ct) \ 1086 (((sp->so_options & SO_TIMESTAMP) && (sp->so_ts_clock == ct)) ? 1 : 0) 1087 1088 void 1089 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip, 1090 struct mbuf *m) 1091 { 1092 bool stamped; 1093 1094 stamped = false; 1095 if ((inp->inp_socket->so_options & SO_BINTIME) || 1096 CHECK_SO_CT(inp->inp_socket, SO_TS_BINTIME)) { 1097 struct bintime boottimebin, bt; 1098 struct timespec ts1; 1099 1100 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR | 1101 M_TSTMP)) { 1102 mbuf_tstmp2timespec(m, &ts1); 1103 timespec2bintime(&ts1, &bt); 1104 getboottimebin(&boottimebin); 1105 bintime_add(&bt, &boottimebin); 1106 } else { 1107 bintime(&bt); 1108 } 1109 *mp = sbcreatecontrol(&bt, sizeof(bt), SCM_BINTIME, 1110 SOL_SOCKET, M_NOWAIT); 1111 if (*mp != NULL) { 1112 mp = &(*mp)->m_next; 1113 stamped = true; 1114 } 1115 } 1116 if (CHECK_SO_CT(inp->inp_socket, SO_TS_REALTIME_MICRO)) { 1117 struct bintime boottimebin, bt1; 1118 struct timespec ts1; 1119 struct timeval tv; 1120 1121 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR | 1122 M_TSTMP)) { 1123 mbuf_tstmp2timespec(m, &ts1); 1124 timespec2bintime(&ts1, &bt1); 1125 getboottimebin(&boottimebin); 1126 bintime_add(&bt1, &boottimebin); 1127 bintime2timeval(&bt1, &tv); 1128 } else { 1129 microtime(&tv); 1130 } 1131 *mp = sbcreatecontrol((caddr_t)&tv, sizeof(tv), SCM_TIMESTAMP, 1132 SOL_SOCKET, M_NOWAIT); 1133 if (*mp != NULL) { 1134 mp = &(*mp)->m_next; 1135 stamped = true; 1136 } 1137 } else if (CHECK_SO_CT(inp->inp_socket, SO_TS_REALTIME)) { 1138 struct bintime boottimebin; 1139 struct timespec ts, ts1; 1140 1141 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR | 1142 M_TSTMP)) { 1143 mbuf_tstmp2timespec(m, &ts); 1144 getboottimebin(&boottimebin); 1145 bintime2timespec(&boottimebin, &ts1); 1146 timespecadd(&ts, &ts1, &ts); 1147 } else { 1148 nanotime(&ts); 1149 } 1150 *mp = sbcreatecontrol(&ts, sizeof(ts), SCM_REALTIME, 1151 SOL_SOCKET, M_NOWAIT); 1152 if (*mp != NULL) { 1153 mp = &(*mp)->m_next; 1154 stamped = true; 1155 } 1156 } else if (CHECK_SO_CT(inp->inp_socket, SO_TS_MONOTONIC)) { 1157 struct timespec ts; 1158 1159 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR | 1160 M_TSTMP)) 1161 mbuf_tstmp2timespec(m, &ts); 1162 else 1163 nanouptime(&ts); 1164 *mp = sbcreatecontrol(&ts, sizeof(ts), SCM_MONOTONIC, 1165 SOL_SOCKET, M_NOWAIT); 1166 if (*mp != NULL) { 1167 mp = &(*mp)->m_next; 1168 stamped = true; 1169 } 1170 } 1171 if (stamped && (m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR | 1172 M_TSTMP)) { 1173 struct sock_timestamp_info sti; 1174 1175 bzero(&sti, sizeof(sti)); 1176 sti.st_info_flags = ST_INFO_HW; 1177 if ((m->m_flags & M_TSTMP_HPREC) != 0) 1178 sti.st_info_flags |= ST_INFO_HW_HPREC; 1179 *mp = sbcreatecontrol(&sti, sizeof(sti), SCM_TIME_INFO, 1180 SOL_SOCKET, M_NOWAIT); 1181 if (*mp != NULL) 1182 mp = &(*mp)->m_next; 1183 } 1184 if (inp->inp_flags & INP_RECVDSTADDR) { 1185 *mp = sbcreatecontrol(&ip->ip_dst, sizeof(struct in_addr), 1186 IP_RECVDSTADDR, IPPROTO_IP, M_NOWAIT); 1187 if (*mp) 1188 mp = &(*mp)->m_next; 1189 } 1190 if (inp->inp_flags & INP_RECVTTL) { 1191 *mp = sbcreatecontrol(&ip->ip_ttl, sizeof(u_char), IP_RECVTTL, 1192 IPPROTO_IP, M_NOWAIT); 1193 if (*mp) 1194 mp = &(*mp)->m_next; 1195 } 1196 #ifdef notyet 1197 /* XXX 1198 * Moving these out of udp_input() made them even more broken 1199 * than they already were. 1200 */ 1201 /* options were tossed already */ 1202 if (inp->inp_flags & INP_RECVOPTS) { 1203 *mp = sbcreatecontrol(opts_deleted_above, 1204 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP, M_NOWAIT); 1205 if (*mp) 1206 mp = &(*mp)->m_next; 1207 } 1208 /* ip_srcroute doesn't do what we want here, need to fix */ 1209 if (inp->inp_flags & INP_RECVRETOPTS) { 1210 *mp = sbcreatecontrol(ip_srcroute(m), sizeof(struct in_addr), 1211 IP_RECVRETOPTS, IPPROTO_IP, M_NOWAIT); 1212 if (*mp) 1213 mp = &(*mp)->m_next; 1214 } 1215 #endif 1216 if (inp->inp_flags & INP_RECVIF) { 1217 struct ifnet *ifp; 1218 struct sdlbuf { 1219 struct sockaddr_dl sdl; 1220 u_char pad[32]; 1221 } sdlbuf; 1222 struct sockaddr_dl *sdp; 1223 struct sockaddr_dl *sdl2 = &sdlbuf.sdl; 1224 1225 if ((ifp = m->m_pkthdr.rcvif)) { 1226 sdp = (struct sockaddr_dl *)ifp->if_addr->ifa_addr; 1227 /* 1228 * Change our mind and don't try copy. 1229 */ 1230 if (sdp->sdl_family != AF_LINK || 1231 sdp->sdl_len > sizeof(sdlbuf)) { 1232 goto makedummy; 1233 } 1234 bcopy(sdp, sdl2, sdp->sdl_len); 1235 } else { 1236 makedummy: 1237 sdl2->sdl_len = 1238 offsetof(struct sockaddr_dl, sdl_data[0]); 1239 sdl2->sdl_family = AF_LINK; 1240 sdl2->sdl_index = 0; 1241 sdl2->sdl_nlen = sdl2->sdl_alen = sdl2->sdl_slen = 0; 1242 } 1243 *mp = sbcreatecontrol(sdl2, sdl2->sdl_len, IP_RECVIF, 1244 IPPROTO_IP, M_NOWAIT); 1245 if (*mp) 1246 mp = &(*mp)->m_next; 1247 } 1248 if (inp->inp_flags & INP_RECVTOS) { 1249 *mp = sbcreatecontrol(&ip->ip_tos, sizeof(u_char), IP_RECVTOS, 1250 IPPROTO_IP, M_NOWAIT); 1251 if (*mp) 1252 mp = &(*mp)->m_next; 1253 } 1254 1255 if (inp->inp_flags2 & INP_RECVFLOWID) { 1256 uint32_t flowid, flow_type; 1257 1258 flowid = m->m_pkthdr.flowid; 1259 flow_type = M_HASHTYPE_GET(m); 1260 1261 /* 1262 * XXX should handle the failure of one or the 1263 * other - don't populate both? 1264 */ 1265 *mp = sbcreatecontrol(&flowid, sizeof(uint32_t), IP_FLOWID, 1266 IPPROTO_IP, M_NOWAIT); 1267 if (*mp) 1268 mp = &(*mp)->m_next; 1269 *mp = sbcreatecontrol(&flow_type, sizeof(uint32_t), 1270 IP_FLOWTYPE, IPPROTO_IP, M_NOWAIT); 1271 if (*mp) 1272 mp = &(*mp)->m_next; 1273 } 1274 1275 #ifdef RSS 1276 if (inp->inp_flags2 & INP_RECVRSSBUCKETID) { 1277 uint32_t flowid, flow_type; 1278 uint32_t rss_bucketid; 1279 1280 flowid = m->m_pkthdr.flowid; 1281 flow_type = M_HASHTYPE_GET(m); 1282 1283 if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) { 1284 *mp = sbcreatecontrol(&rss_bucketid, sizeof(uint32_t), 1285 IP_RSSBUCKETID, IPPROTO_IP, M_NOWAIT); 1286 if (*mp) 1287 mp = &(*mp)->m_next; 1288 } 1289 } 1290 #endif 1291 } 1292 1293 /* 1294 * XXXRW: Multicast routing code in ip_mroute.c is generally MPSAFE, but the 1295 * ip_rsvp and ip_rsvp_on variables need to be interlocked with rsvp_on 1296 * locking. This code remains in ip_input.c as ip_mroute.c is optionally 1297 * compiled. 1298 */ 1299 VNET_DEFINE_STATIC(int, ip_rsvp_on); 1300 VNET_DEFINE(struct socket *, ip_rsvpd); 1301 1302 #define V_ip_rsvp_on VNET(ip_rsvp_on) 1303 1304 int 1305 ip_rsvp_init(struct socket *so) 1306 { 1307 1308 if (V_ip_rsvpd != NULL) 1309 return EADDRINUSE; 1310 1311 V_ip_rsvpd = so; 1312 /* 1313 * This may seem silly, but we need to be sure we don't over-increment 1314 * the RSVP counter, in case something slips up. 1315 */ 1316 if (!V_ip_rsvp_on) { 1317 V_ip_rsvp_on = 1; 1318 V_rsvp_on++; 1319 } 1320 1321 return 0; 1322 } 1323 1324 int 1325 ip_rsvp_done(void) 1326 { 1327 1328 V_ip_rsvpd = NULL; 1329 /* 1330 * This may seem silly, but we need to be sure we don't over-decrement 1331 * the RSVP counter, in case something slips up. 1332 */ 1333 if (V_ip_rsvp_on) { 1334 V_ip_rsvp_on = 0; 1335 V_rsvp_on--; 1336 } 1337 return 0; 1338 } 1339 1340 int 1341 rsvp_input(struct mbuf **mp, int *offp, int proto) 1342 { 1343 struct mbuf *m; 1344 1345 m = *mp; 1346 *mp = NULL; 1347 1348 if (rsvp_input_p) { /* call the real one if loaded */ 1349 *mp = m; 1350 rsvp_input_p(mp, offp, proto); 1351 return (IPPROTO_DONE); 1352 } 1353 1354 /* Can still get packets with rsvp_on = 0 if there is a local member 1355 * of the group to which the RSVP packet is addressed. But in this 1356 * case we want to throw the packet away. 1357 */ 1358 1359 if (!V_rsvp_on) { 1360 m_freem(m); 1361 return (IPPROTO_DONE); 1362 } 1363 1364 if (V_ip_rsvpd != NULL) { 1365 *mp = m; 1366 rip_input(mp, offp, proto); 1367 return (IPPROTO_DONE); 1368 } 1369 /* Drop the packet */ 1370 m_freem(m); 1371 return (IPPROTO_DONE); 1372 } 1373