2 * Copyright (c) 1982, 1986, 1988, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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)
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26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
35 #include "opt_bootp.h"
37 #include "opt_ipstealth.h"
38 #include "opt_ipsec.h"
39 #include "opt_route.h"
42 #include <sys/param.h>
43 #include <sys/systm.h>
45 #include <sys/malloc.h>
46 #include <sys/domain.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
50 #include <sys/kernel.h>
52 #include <sys/rwlock.h>
54 #include <sys/syslog.h>
55 #include <sys/sysctl.h>
59 #include <net/if_types.h>
60 #include <net/if_var.h>
61 #include <net/if_dl.h>
62 #include <net/route.h>
63 #include <net/netisr.h>
66 #include <netinet/in.h>
67 #include <netinet/in_kdtrace.h>
68 #include <netinet/in_systm.h>
69 #include <netinet/in_var.h>
70 #include <netinet/ip.h>
71 #include <netinet/in_pcb.h>
72 #include <netinet/ip_var.h>
73 #include <netinet/ip_fw.h>
74 #include <netinet/ip_icmp.h>
75 #include <netinet/ip_options.h>
76 #include <machine/in_cksum.h>
77 #include <netinet/ip_carp.h>
79 #include <netinet/ip_ipsec.h>
81 #include <netinet/in_rss.h>
83 #include <sys/socketvar.h>
85 #include <security/mac/mac_framework.h>
88 CTASSERT(sizeof(struct ip) == 20);
91 struct rwlock in_ifaddr_lock;
92 RW_SYSINIT(in_ifaddr_lock, &in_ifaddr_lock, "in_ifaddr_lock");
94 VNET_DEFINE(int, rsvp_on);
96 VNET_DEFINE(int, ipforwarding);
97 SYSCTL_INT(_net_inet_ip, IPCTL_FORWARDING, forwarding, CTLFLAG_VNET | CTLFLAG_RW,
98 &VNET_NAME(ipforwarding), 0,
99 "Enable IP forwarding between interfaces");
101 static VNET_DEFINE(int, ipsendredirects) = 1; /* XXX */
102 #define V_ipsendredirects VNET(ipsendredirects)
103 SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect, CTLFLAG_VNET | CTLFLAG_RW,
104 &VNET_NAME(ipsendredirects), 0,
105 "Enable sending IP redirects");
107 VNET_DEFINE(int, ip_do_randomid);
108 SYSCTL_INT(_net_inet_ip, OID_AUTO, random_id, CTLFLAG_VNET | CTLFLAG_RW,
109 &VNET_NAME(ip_do_randomid), 0,
110 "Assign random ip_id values");
113 * XXX - Setting ip_checkinterface mostly implements the receive side of
114 * the Strong ES model described in RFC 1122, but since the routing table
115 * and transmit implementation do not implement the Strong ES model,
116 * setting this to 1 results in an odd hybrid.
118 * XXX - ip_checkinterface currently must be disabled if you use ipnat
119 * to translate the destination address to another local interface.
121 * XXX - ip_checkinterface must be disabled if you add IP aliases
122 * to the loopback interface instead of the interface where the
123 * packets for those addresses are received.
125 static VNET_DEFINE(int, ip_checkinterface);
126 #define V_ip_checkinterface VNET(ip_checkinterface)
127 SYSCTL_INT(_net_inet_ip, OID_AUTO, check_interface, CTLFLAG_VNET | CTLFLAG_RW,
128 &VNET_NAME(ip_checkinterface), 0,
129 "Verify packet arrives on correct interface");
131 VNET_DEFINE(struct pfil_head, inet_pfil_hook); /* Packet filter hooks */
133 static struct netisr_handler ip_nh = {
135 .nh_handler = ip_input,
136 .nh_proto = NETISR_IP,
138 .nh_m2cpuid = rss_soft_m2cpuid,
139 .nh_policy = NETISR_POLICY_CPU,
140 .nh_dispatch = NETISR_DISPATCH_HYBRID,
142 .nh_policy = NETISR_POLICY_FLOW,
148 * Directly dispatched frames are currently assumed
149 * to have a flowid already calculated.
151 * It should likely have something that assert it
152 * actually has valid flow details.
154 static struct netisr_handler ip_direct_nh = {
155 .nh_name = "ip_direct",
156 .nh_handler = ip_direct_input,
157 .nh_proto = NETISR_IP_DIRECT,
158 .nh_m2cpuid = rss_m2cpuid,
159 .nh_policy = NETISR_POLICY_CPU,
160 .nh_dispatch = NETISR_DISPATCH_HYBRID,
164 extern struct domain inetdomain;
165 extern struct protosw inetsw[];
166 u_char ip_protox[IPPROTO_MAX];
167 VNET_DEFINE(struct in_ifaddrhead, in_ifaddrhead); /* first inet address */
168 VNET_DEFINE(struct in_ifaddrhashhead *, in_ifaddrhashtbl); /* inet addr hash table */
169 VNET_DEFINE(u_long, in_ifaddrhmask); /* mask for hash table */
171 static VNET_DEFINE(uma_zone_t, ipq_zone);
172 static VNET_DEFINE(TAILQ_HEAD(ipqhead, ipq), ipq[IPREASS_NHASH]);
173 static struct mtx ipqlock;
175 #define V_ipq_zone VNET(ipq_zone)
176 #define V_ipq VNET(ipq)
178 #define IPQ_LOCK() mtx_lock(&ipqlock)
179 #define IPQ_UNLOCK() mtx_unlock(&ipqlock)
180 #define IPQ_LOCK_INIT() mtx_init(&ipqlock, "ipqlock", NULL, MTX_DEF)
181 #define IPQ_LOCK_ASSERT() mtx_assert(&ipqlock, MA_OWNED)
183 static void maxnipq_update(void);
184 static void ipq_zone_change(void *);
185 static void ip_drain_locked(void);
187 static VNET_DEFINE(int, maxnipq); /* Administrative limit on # reass queues. */
188 static VNET_DEFINE(int, nipq); /* Total # of reass queues */
189 #define V_maxnipq VNET(maxnipq)
190 #define V_nipq VNET(nipq)
191 SYSCTL_INT(_net_inet_ip, OID_AUTO, fragpackets, CTLFLAG_VNET | CTLFLAG_RD,
193 "Current number of IPv4 fragment reassembly queue entries");
195 static VNET_DEFINE(int, maxfragsperpacket);
196 #define V_maxfragsperpacket VNET(maxfragsperpacket)
197 SYSCTL_INT(_net_inet_ip, OID_AUTO, maxfragsperpacket, CTLFLAG_VNET | CTLFLAG_RW,
198 &VNET_NAME(maxfragsperpacket), 0,
199 "Maximum number of IPv4 fragments allowed per packet");
202 SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW,
203 &ip_mtu, 0, "Default MTU");
207 VNET_DEFINE(int, ipstealth);
208 SYSCTL_INT(_net_inet_ip, OID_AUTO, stealth, CTLFLAG_VNET | CTLFLAG_RW,
209 &VNET_NAME(ipstealth), 0,
210 "IP stealth mode, no TTL decrementation on forwarding");
213 static void ip_freef(struct ipqhead *, struct ipq *);
216 * IP statistics are stored in the "array" of counter(9)s.
218 VNET_PCPUSTAT_DEFINE(struct ipstat, ipstat);
219 VNET_PCPUSTAT_SYSINIT(ipstat);
220 SYSCTL_VNET_PCPUSTAT(_net_inet_ip, IPCTL_STATS, stats, struct ipstat, ipstat,
221 "IP statistics (struct ipstat, netinet/ip_var.h)");
224 VNET_PCPUSTAT_SYSUNINIT(ipstat);
228 * Kernel module interface for updating ipstat. The argument is an index
229 * into ipstat treated as an array.
232 kmod_ipstat_inc(int statnum)
235 counter_u64_add(VNET(ipstat)[statnum], 1);
239 kmod_ipstat_dec(int statnum)
242 counter_u64_add(VNET(ipstat)[statnum], -1);
246 sysctl_netinet_intr_queue_maxlen(SYSCTL_HANDLER_ARGS)
250 netisr_getqlimit(&ip_nh, &qlimit);
251 error = sysctl_handle_int(oidp, &qlimit, 0, req);
252 if (error || !req->newptr)
256 return (netisr_setqlimit(&ip_nh, qlimit));
258 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen,
259 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_netinet_intr_queue_maxlen, "I",
260 "Maximum size of the IP input queue");
263 sysctl_netinet_intr_queue_drops(SYSCTL_HANDLER_ARGS)
265 u_int64_t qdrops_long;
268 netisr_getqdrops(&ip_nh, &qdrops_long);
269 qdrops = qdrops_long;
270 error = sysctl_handle_int(oidp, &qdrops, 0, req);
271 if (error || !req->newptr)
275 netisr_clearqdrops(&ip_nh);
279 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops,
280 CTLTYPE_INT|CTLFLAG_RD, 0, 0, sysctl_netinet_intr_queue_drops, "I",
281 "Number of packets dropped from the IP input queue");
285 sysctl_netinet_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS)
289 netisr_getqlimit(&ip_direct_nh, &qlimit);
290 error = sysctl_handle_int(oidp, &qlimit, 0, req);
291 if (error || !req->newptr)
295 return (netisr_setqlimit(&ip_direct_nh, qlimit));
297 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_direct_queue_maxlen,
298 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_netinet_intr_direct_queue_maxlen, "I",
299 "Maximum size of the IP direct input queue");
302 sysctl_netinet_intr_direct_queue_drops(SYSCTL_HANDLER_ARGS)
304 u_int64_t qdrops_long;
307 netisr_getqdrops(&ip_direct_nh, &qdrops_long);
308 qdrops = qdrops_long;
309 error = sysctl_handle_int(oidp, &qdrops, 0, req);
310 if (error || !req->newptr)
314 netisr_clearqdrops(&ip_direct_nh);
318 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQDROPS, intr_direct_queue_drops,
319 CTLTYPE_INT|CTLFLAG_RD, 0, 0, sysctl_netinet_intr_direct_queue_drops, "I",
320 "Number of packets dropped from the IP direct input queue");
324 * IP initialization: fill in IP protocol switch table.
325 * All protocols not implemented in kernel go to raw IP protocol handler.
333 V_ip_id = time_second & 0xffff;
335 TAILQ_INIT(&V_in_ifaddrhead);
336 V_in_ifaddrhashtbl = hashinit(INADDR_NHASH, M_IFADDR, &V_in_ifaddrhmask);
338 /* Initialize IP reassembly queue. */
339 for (i = 0; i < IPREASS_NHASH; i++)
340 TAILQ_INIT(&V_ipq[i]);
341 V_maxnipq = nmbclusters / 32;
342 V_maxfragsperpacket = 16;
343 V_ipq_zone = uma_zcreate("ipq", sizeof(struct ipq), NULL, NULL, NULL,
344 NULL, UMA_ALIGN_PTR, 0);
347 /* Initialize packet filter hooks. */
348 V_inet_pfil_hook.ph_type = PFIL_TYPE_AF;
349 V_inet_pfil_hook.ph_af = AF_INET;
350 if ((i = pfil_head_register(&V_inet_pfil_hook)) != 0)
351 printf("%s: WARNING: unable to register pfil hook, "
352 "error %d\n", __func__, i);
354 /* Skip initialization of globals for non-default instances. */
355 if (!IS_DEFAULT_VNET(curvnet))
358 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
360 panic("ip_init: PF_INET not found");
362 /* Initialize the entire ip_protox[] array to IPPROTO_RAW. */
363 for (i = 0; i < IPPROTO_MAX; i++)
364 ip_protox[i] = pr - inetsw;
366 * Cycle through IP protocols and put them into the appropriate place
369 for (pr = inetdomain.dom_protosw;
370 pr < inetdomain.dom_protoswNPROTOSW; pr++)
371 if (pr->pr_domain->dom_family == PF_INET &&
372 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) {
373 /* Be careful to only index valid IP protocols. */
374 if (pr->pr_protocol < IPPROTO_MAX)
375 ip_protox[pr->pr_protocol] = pr - inetsw;
378 EVENTHANDLER_REGISTER(nmbclusters_change, ipq_zone_change,
379 NULL, EVENTHANDLER_PRI_ANY);
381 /* Initialize various other remaining things. */
383 netisr_register(&ip_nh);
385 netisr_register(&ip_direct_nh);
395 if ((i = pfil_head_unregister(&V_inet_pfil_hook)) != 0)
396 printf("%s: WARNING: unable to unregister pfil hook, "
397 "error %d\n", __func__, i);
399 /* Cleanup in_ifaddr hash table; should be empty. */
400 hashdestroy(V_in_ifaddrhashtbl, M_IFADDR, V_in_ifaddrhmask);
406 uma_zdestroy(V_ipq_zone);
412 * IP direct input routine.
414 * This is called when reinjecting completed fragments where
415 * all of the previous checking and book-keeping has been done.
418 ip_direct_input(struct mbuf *m)
423 ip = mtod(m, struct ip *);
424 hlen = ip->ip_hl << 2;
426 IPSTAT_INC(ips_delivered);
427 (*inetsw[ip_protox[ip->ip_p]].pr_input)(&m, &hlen, ip->ip_p);
433 * Ip input routine. Checksum and byte swap header. If fragmented
434 * try to reassemble. Process options. Pass to next level.
437 ip_input(struct mbuf *m)
439 struct ip *ip = NULL;
440 struct in_ifaddr *ia = NULL;
443 int checkif, hlen = 0;
444 uint16_t sum, ip_len;
445 int dchg = 0; /* dest changed after fw */
446 struct in_addr odst; /* original dst address */
450 if (m->m_flags & M_FASTFWD_OURS) {
451 m->m_flags &= ~M_FASTFWD_OURS;
452 /* Set up some basics that will be used later. */
453 ip = mtod(m, struct ip *);
454 hlen = ip->ip_hl << 2;
455 ip_len = ntohs(ip->ip_len);
459 IPSTAT_INC(ips_total);
461 if (m->m_pkthdr.len < sizeof(struct ip))
464 if (m->m_len < sizeof (struct ip) &&
465 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
466 IPSTAT_INC(ips_toosmall);
469 ip = mtod(m, struct ip *);
471 if (ip->ip_v != IPVERSION) {
472 IPSTAT_INC(ips_badvers);
476 hlen = ip->ip_hl << 2;
477 if (hlen < sizeof(struct ip)) { /* minimum header length */
478 IPSTAT_INC(ips_badhlen);
481 if (hlen > m->m_len) {
482 if ((m = m_pullup(m, hlen)) == NULL) {
483 IPSTAT_INC(ips_badhlen);
486 ip = mtod(m, struct ip *);
489 IP_PROBE(receive, NULL, NULL, ip, m->m_pkthdr.rcvif, ip, NULL);
491 /* 127/8 must not appear on wire - RFC1122 */
492 ifp = m->m_pkthdr.rcvif;
493 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
494 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
495 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
496 IPSTAT_INC(ips_badaddr);
501 if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) {
502 sum = !(m->m_pkthdr.csum_flags & CSUM_IP_VALID);
504 if (hlen == sizeof(struct ip)) {
505 sum = in_cksum_hdr(ip);
507 sum = in_cksum(m, hlen);
511 IPSTAT_INC(ips_badsum);
516 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0)
517 /* packet is dropped by traffic conditioner */
521 ip_len = ntohs(ip->ip_len);
523 IPSTAT_INC(ips_badlen);
528 * Check that the amount of data in the buffers
529 * is as at least much as the IP header would have us expect.
530 * Trim mbufs if longer than we expect.
531 * Drop packet if shorter than we expect.
533 if (m->m_pkthdr.len < ip_len) {
535 IPSTAT_INC(ips_tooshort);
538 if (m->m_pkthdr.len > ip_len) {
539 if (m->m_len == m->m_pkthdr.len) {
541 m->m_pkthdr.len = ip_len;
543 m_adj(m, ip_len - m->m_pkthdr.len);
548 * Bypass packet filtering for packets previously handled by IPsec.
550 if (ip_ipsec_filtertunnel(m))
555 * Run through list of hooks for input packets.
557 * NB: Beware of the destination address changing (e.g.
558 * by NAT rewriting). When this happens, tell
559 * ip_forward to do the right thing.
562 /* Jump over all PFIL processing if hooks are not active. */
563 if (!PFIL_HOOKED(&V_inet_pfil_hook))
567 if (pfil_run_hooks(&V_inet_pfil_hook, &m, ifp, PFIL_IN, NULL) != 0)
569 if (m == NULL) /* consumed by filter */
572 ip = mtod(m, struct ip *);
573 dchg = (odst.s_addr != ip->ip_dst.s_addr);
574 ifp = m->m_pkthdr.rcvif;
576 if (m->m_flags & M_FASTFWD_OURS) {
577 m->m_flags &= ~M_FASTFWD_OURS;
580 if (m->m_flags & M_IP_NEXTHOP) {
581 dchg = (m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL);
584 * Directly ship the packet on. This allows
585 * forwarding packets originally destined to us
586 * to some other directly connected host.
595 * Process options and, if not destined for us,
596 * ship it on. ip_dooptions returns 1 when an
597 * error was detected (causing an icmp message
598 * to be sent and the original packet to be freed).
600 if (hlen > sizeof (struct ip) && ip_dooptions(m, 0))
603 /* greedy RSVP, snatches any PATH packet of the RSVP protocol and no
604 * matter if it is destined to another node, or whether it is
605 * a multicast one, RSVP wants it! and prevents it from being forwarded
606 * anywhere else. Also checks if the rsvp daemon is running before
607 * grabbing the packet.
609 if (V_rsvp_on && ip->ip_p==IPPROTO_RSVP)
613 * Check our list of addresses, to see if the packet is for us.
614 * If we don't have any addresses, assume any unicast packet
615 * we receive might be for us (and let the upper layers deal
618 if (TAILQ_EMPTY(&V_in_ifaddrhead) &&
619 (m->m_flags & (M_MCAST|M_BCAST)) == 0)
623 * Enable a consistency check between the destination address
624 * and the arrival interface for a unicast packet (the RFC 1122
625 * strong ES model) if IP forwarding is disabled and the packet
626 * is not locally generated and the packet is not subject to
629 * XXX - Checking also should be disabled if the destination
630 * address is ipnat'ed to a different interface.
632 * XXX - Checking is incompatible with IP aliases added
633 * to the loopback interface instead of the interface where
634 * the packets are received.
636 * XXX - This is the case for carp vhost IPs as well so we
637 * insert a workaround. If the packet got here, we already
638 * checked with carp_iamatch() and carp_forus().
640 checkif = V_ip_checkinterface && (V_ipforwarding == 0) &&
641 ifp != NULL && ((ifp->if_flags & IFF_LOOPBACK) == 0) &&
642 ifp->if_carp == NULL && (dchg == 0);
645 * Check for exact addresses in the hash bucket.
647 /* IN_IFADDR_RLOCK(); */
648 LIST_FOREACH(ia, INADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
650 * If the address matches, verify that the packet
651 * arrived via the correct interface if checking is
654 if (IA_SIN(ia)->sin_addr.s_addr == ip->ip_dst.s_addr &&
655 (!checkif || ia->ia_ifp == ifp)) {
656 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
657 counter_u64_add(ia->ia_ifa.ifa_ibytes,
659 /* IN_IFADDR_RUNLOCK(); */
663 /* IN_IFADDR_RUNLOCK(); */
666 * Check for broadcast addresses.
668 * Only accept broadcast packets that arrive via the matching
669 * interface. Reception of forwarded directed broadcasts would
670 * be handled via ip_forward() and ether_output() with the loopback
671 * into the stack for SIMPLEX interfaces handled by ether_output().
673 if (ifp != NULL && ifp->if_flags & IFF_BROADCAST) {
675 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
676 if (ifa->ifa_addr->sa_family != AF_INET)
679 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr ==
681 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
682 counter_u64_add(ia->ia_ifa.ifa_ibytes,
684 IF_ADDR_RUNLOCK(ifp);
688 if (IA_SIN(ia)->sin_addr.s_addr == INADDR_ANY) {
689 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
690 counter_u64_add(ia->ia_ifa.ifa_ibytes,
692 IF_ADDR_RUNLOCK(ifp);
697 IF_ADDR_RUNLOCK(ifp);
700 /* RFC 3927 2.7: Do not forward datagrams for 169.254.0.0/16. */
701 if (IN_LINKLOCAL(ntohl(ip->ip_dst.s_addr))) {
702 IPSTAT_INC(ips_cantforward);
706 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
709 * If we are acting as a multicast router, all
710 * incoming multicast packets are passed to the
711 * kernel-level multicast forwarding function.
712 * The packet is returned (relatively) intact; if
713 * ip_mforward() returns a non-zero value, the packet
714 * must be discarded, else it may be accepted below.
716 if (ip_mforward && ip_mforward(ip, ifp, m, 0) != 0) {
717 IPSTAT_INC(ips_cantforward);
723 * The process-level routing daemon needs to receive
724 * all multicast IGMP packets, whether or not this
725 * host belongs to their destination groups.
727 if (ip->ip_p == IPPROTO_IGMP)
729 IPSTAT_INC(ips_forward);
732 * Assume the packet is for us, to avoid prematurely taking
733 * a lock on the in_multi hash. Protocols must perform
734 * their own filtering and update statistics accordingly.
738 if (ip->ip_dst.s_addr == (u_long)INADDR_BROADCAST)
740 if (ip->ip_dst.s_addr == INADDR_ANY)
744 * Not for us; forward if possible and desirable.
746 if (V_ipforwarding == 0) {
747 IPSTAT_INC(ips_cantforward);
761 * IPSTEALTH: Process non-routing options only
762 * if the packet is destined for us.
764 if (V_ipstealth && hlen > sizeof (struct ip) && ip_dooptions(m, 1))
766 #endif /* IPSTEALTH */
769 * Attempt reassembly; if it succeeds, proceed.
770 * ip_reass() will return a different mbuf.
772 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) {
773 /* XXXGL: shouldn't we save & set m_flags? */
777 ip = mtod(m, struct ip *);
778 /* Get the header length of the reassembled packet */
779 hlen = ip->ip_hl << 2;
784 * enforce IPsec policy checking if we are seeing last header.
785 * note that we do not visit this with protocols with pcb layer
786 * code - like udp/tcp/raw ip.
788 if (ip_ipsec_input(m))
793 * Switch out to protocol's input routine.
795 IPSTAT_INC(ips_delivered);
797 (*inetsw[ip_protox[ip->ip_p]].pr_input)(&m, &hlen, ip->ip_p);
804 * After maxnipq has been updated, propagate the change to UMA. The UMA zone
805 * max has slightly different semantics than the sysctl, for historical
813 * -1 for unlimited allocation.
816 uma_zone_set_max(V_ipq_zone, 0);
818 * Positive number for specific bound.
821 uma_zone_set_max(V_ipq_zone, V_maxnipq);
823 * Zero specifies no further fragment queue allocation -- set the
824 * bound very low, but rely on implementation elsewhere to actually
825 * prevent allocation and reclaim current queues.
828 uma_zone_set_max(V_ipq_zone, 1);
832 ipq_zone_change(void *tag)
835 if (V_maxnipq > 0 && V_maxnipq < (nmbclusters / 32)) {
836 V_maxnipq = nmbclusters / 32;
842 sysctl_maxnipq(SYSCTL_HANDLER_ARGS)
847 error = sysctl_handle_int(oidp, &i, 0, req);
848 if (error || !req->newptr)
852 * XXXRW: Might be a good idea to sanity check the argument and place
853 * an extreme upper bound.
862 SYSCTL_PROC(_net_inet_ip, OID_AUTO, maxfragpackets, CTLTYPE_INT|CTLFLAG_RW,
863 NULL, 0, sysctl_maxnipq, "I",
864 "Maximum number of IPv4 fragment reassembly queue entries");
866 #define M_IP_FRAG M_PROTO9
869 * Take incoming datagram fragment and try to reassemble it into
870 * whole datagram. If the argument is the first fragment or one
871 * in between the function will return NULL and store the mbuf
872 * in the fragment chain. If the argument is the last fragment
873 * the packet will be reassembled and the pointer to the new
874 * mbuf returned for further processing. Only m_tags attached
875 * to the first packet/fragment are preserved.
876 * The IP header is *NOT* adjusted out of iplen.
879 ip_reass(struct mbuf *m)
882 struct mbuf *p, *q, *nq, *t;
883 struct ipq *fp = NULL;
884 struct ipqhead *head;
889 uint32_t rss_hash, rss_type;
892 /* If maxnipq or maxfragsperpacket are 0, never accept fragments. */
893 if (V_maxnipq == 0 || V_maxfragsperpacket == 0) {
894 IPSTAT_INC(ips_fragments);
895 IPSTAT_INC(ips_fragdropped);
900 ip = mtod(m, struct ip *);
901 hlen = ip->ip_hl << 2;
903 hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id);
908 * Look for queue of fragments
911 TAILQ_FOREACH(fp, head, ipq_list)
912 if (ip->ip_id == fp->ipq_id &&
913 ip->ip_src.s_addr == fp->ipq_src.s_addr &&
914 ip->ip_dst.s_addr == fp->ipq_dst.s_addr &&
916 mac_ipq_match(m, fp) &&
918 ip->ip_p == fp->ipq_p)
924 * Attempt to trim the number of allocated fragment queues if it
925 * exceeds the administrative limit.
927 if ((V_nipq > V_maxnipq) && (V_maxnipq > 0)) {
929 * drop something from the tail of the current queue
930 * before proceeding further
932 struct ipq *q = TAILQ_LAST(head, ipqhead);
933 if (q == NULL) { /* gak */
934 for (i = 0; i < IPREASS_NHASH; i++) {
935 struct ipq *r = TAILQ_LAST(&V_ipq[i], ipqhead);
937 IPSTAT_ADD(ips_fragtimeout,
939 ip_freef(&V_ipq[i], r);
944 IPSTAT_ADD(ips_fragtimeout, q->ipq_nfrags);
951 * Adjust ip_len to not reflect header,
952 * convert offset of this to bytes.
954 ip->ip_len = htons(ntohs(ip->ip_len) - hlen);
955 if (ip->ip_off & htons(IP_MF)) {
957 * Make sure that fragments have a data length
958 * that's a non-zero multiple of 8 bytes.
960 if (ip->ip_len == htons(0) || (ntohs(ip->ip_len) & 0x7) != 0) {
961 IPSTAT_INC(ips_toosmall); /* XXX */
964 m->m_flags |= M_IP_FRAG;
966 m->m_flags &= ~M_IP_FRAG;
967 ip->ip_off = htons(ntohs(ip->ip_off) << 3);
970 * Attempt reassembly; if it succeeds, proceed.
971 * ip_reass() will return a different mbuf.
973 IPSTAT_INC(ips_fragments);
974 m->m_pkthdr.PH_loc.ptr = ip;
976 /* Previous ip_reass() started here. */
978 * Presence of header sizes in mbufs
979 * would confuse code below.
985 * If first fragment to arrive, create a reassembly queue.
988 fp = uma_zalloc(V_ipq_zone, M_NOWAIT);
992 if (mac_ipq_init(fp, M_NOWAIT) != 0) {
993 uma_zfree(V_ipq_zone, fp);
997 mac_ipq_create(m, fp);
999 TAILQ_INSERT_HEAD(head, fp, ipq_list);
1002 fp->ipq_ttl = IPFRAGTTL;
1003 fp->ipq_p = ip->ip_p;
1004 fp->ipq_id = ip->ip_id;
1005 fp->ipq_src = ip->ip_src;
1006 fp->ipq_dst = ip->ip_dst;
1008 m->m_nextpkt = NULL;
1013 mac_ipq_update(m, fp);
1017 #define GETIP(m) ((struct ip*)((m)->m_pkthdr.PH_loc.ptr))
1020 * Handle ECN by comparing this segment with the first one;
1021 * if CE is set, do not lose CE.
1022 * drop if CE and not-ECT are mixed for the same packet.
1024 ecn = ip->ip_tos & IPTOS_ECN_MASK;
1025 ecn0 = GETIP(fp->ipq_frags)->ip_tos & IPTOS_ECN_MASK;
1026 if (ecn == IPTOS_ECN_CE) {
1027 if (ecn0 == IPTOS_ECN_NOTECT)
1029 if (ecn0 != IPTOS_ECN_CE)
1030 GETIP(fp->ipq_frags)->ip_tos |= IPTOS_ECN_CE;
1032 if (ecn == IPTOS_ECN_NOTECT && ecn0 != IPTOS_ECN_NOTECT)
1036 * Find a segment which begins after this one does.
1038 for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt)
1039 if (ntohs(GETIP(q)->ip_off) > ntohs(ip->ip_off))
1043 * If there is a preceding segment, it may provide some of
1044 * our data already. If so, drop the data from the incoming
1045 * segment. If it provides all of our data, drop us, otherwise
1046 * stick new segment in the proper place.
1048 * If some of the data is dropped from the preceding
1049 * segment, then it's checksum is invalidated.
1052 i = ntohs(GETIP(p)->ip_off) + ntohs(GETIP(p)->ip_len) -
1055 if (i >= ntohs(ip->ip_len))
1058 m->m_pkthdr.csum_flags = 0;
1059 ip->ip_off = htons(ntohs(ip->ip_off) + i);
1060 ip->ip_len = htons(ntohs(ip->ip_len) - i);
1062 m->m_nextpkt = p->m_nextpkt;
1065 m->m_nextpkt = fp->ipq_frags;
1070 * While we overlap succeeding segments trim them or,
1071 * if they are completely covered, dequeue them.
1073 for (; q != NULL && ntohs(ip->ip_off) + ntohs(ip->ip_len) >
1074 ntohs(GETIP(q)->ip_off); q = nq) {
1075 i = (ntohs(ip->ip_off) + ntohs(ip->ip_len)) -
1076 ntohs(GETIP(q)->ip_off);
1077 if (i < ntohs(GETIP(q)->ip_len)) {
1078 GETIP(q)->ip_len = htons(ntohs(GETIP(q)->ip_len) - i);
1079 GETIP(q)->ip_off = htons(ntohs(GETIP(q)->ip_off) + i);
1081 q->m_pkthdr.csum_flags = 0;
1086 IPSTAT_INC(ips_fragdropped);
1092 * Check for complete reassembly and perform frag per packet
1095 * Frag limiting is performed here so that the nth frag has
1096 * a chance to complete the packet before we drop the packet.
1097 * As a result, n+1 frags are actually allowed per packet, but
1098 * only n will ever be stored. (n = maxfragsperpacket.)
1102 for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt) {
1103 if (ntohs(GETIP(q)->ip_off) != next) {
1104 if (fp->ipq_nfrags > V_maxfragsperpacket) {
1105 IPSTAT_ADD(ips_fragdropped, fp->ipq_nfrags);
1110 next += ntohs(GETIP(q)->ip_len);
1112 /* Make sure the last packet didn't have the IP_MF flag */
1113 if (p->m_flags & M_IP_FRAG) {
1114 if (fp->ipq_nfrags > V_maxfragsperpacket) {
1115 IPSTAT_ADD(ips_fragdropped, fp->ipq_nfrags);
1122 * Reassembly is complete. Make sure the packet is a sane size.
1126 if (next + (ip->ip_hl << 2) > IP_MAXPACKET) {
1127 IPSTAT_INC(ips_toolong);
1128 IPSTAT_ADD(ips_fragdropped, fp->ipq_nfrags);
1134 * Concatenate fragments.
1141 q->m_nextpkt = NULL;
1142 for (q = nq; q != NULL; q = nq) {
1144 q->m_nextpkt = NULL;
1145 m->m_pkthdr.csum_flags &= q->m_pkthdr.csum_flags;
1146 m->m_pkthdr.csum_data += q->m_pkthdr.csum_data;
1150 * In order to do checksumming faster we do 'end-around carry' here
1151 * (and not in for{} loop), though it implies we are not going to
1152 * reassemble more than 64k fragments.
1154 while (m->m_pkthdr.csum_data & 0xffff0000)
1155 m->m_pkthdr.csum_data = (m->m_pkthdr.csum_data & 0xffff) +
1156 (m->m_pkthdr.csum_data >> 16);
1158 mac_ipq_reassemble(fp, m);
1159 mac_ipq_destroy(fp);
1163 * Create header for new ip packet by modifying header of first
1164 * packet; dequeue and discard fragment reassembly header.
1165 * Make header visible.
1167 ip->ip_len = htons((ip->ip_hl << 2) + next);
1168 ip->ip_src = fp->ipq_src;
1169 ip->ip_dst = fp->ipq_dst;
1170 TAILQ_REMOVE(head, fp, ipq_list);
1172 uma_zfree(V_ipq_zone, fp);
1173 m->m_len += (ip->ip_hl << 2);
1174 m->m_data -= (ip->ip_hl << 2);
1175 /* some debugging cruft by sklower, below, will go away soon */
1176 if (m->m_flags & M_PKTHDR) /* XXX this should be done elsewhere */
1178 IPSTAT_INC(ips_reassembled);
1183 * Query the RSS layer for the flowid / flowtype for the
1186 * For now, just assume we have to calculate a new one.
1187 * Later on we should check to see if the assigned flowid matches
1188 * what RSS wants for the given IP protocol and if so, just keep it.
1190 * We then queue into the relevant netisr so it can be dispatched
1191 * to the correct CPU.
1193 * Note - this may return 1, which means the flowid in the mbuf
1194 * is correct for the configured RSS hash types and can be used.
1196 if (rss_mbuf_software_hash_v4(m, 0, &rss_hash, &rss_type) == 0) {
1197 m->m_pkthdr.flowid = rss_hash;
1198 M_HASHTYPE_SET(m, rss_type);
1202 * Queue/dispatch for reprocessing.
1204 * Note: this is much slower than just handling the frame in the
1205 * current receive context. It's likely worth investigating
1208 netisr_dispatch(NETISR_IP_DIRECT, m);
1212 /* Handle in-line */
1216 IPSTAT_INC(ips_fragdropped);
1228 * Free a fragment reassembly header and all
1229 * associated datagrams.
1232 ip_freef(struct ipqhead *fhp, struct ipq *fp)
1238 while (fp->ipq_frags) {
1240 fp->ipq_frags = q->m_nextpkt;
1243 TAILQ_REMOVE(fhp, fp, ipq_list);
1244 uma_zfree(V_ipq_zone, fp);
1249 * IP timer processing;
1250 * if a timer expires on a reassembly
1251 * queue, discard it.
1256 VNET_ITERATOR_DECL(vnet_iter);
1260 VNET_LIST_RLOCK_NOSLEEP();
1262 VNET_FOREACH(vnet_iter) {
1263 CURVNET_SET(vnet_iter);
1264 for (i = 0; i < IPREASS_NHASH; i++) {
1265 for(fp = TAILQ_FIRST(&V_ipq[i]); fp;) {
1269 fp = TAILQ_NEXT(fp, ipq_list);
1270 if(--fpp->ipq_ttl == 0) {
1271 IPSTAT_ADD(ips_fragtimeout,
1273 ip_freef(&V_ipq[i], fpp);
1278 * If we are over the maximum number of fragments
1279 * (due to the limit being lowered), drain off
1280 * enough to get down to the new limit.
1282 if (V_maxnipq >= 0 && V_nipq > V_maxnipq) {
1283 for (i = 0; i < IPREASS_NHASH; i++) {
1284 while (V_nipq > V_maxnipq &&
1285 !TAILQ_EMPTY(&V_ipq[i])) {
1286 IPSTAT_ADD(ips_fragdropped,
1287 TAILQ_FIRST(&V_ipq[i])->ipq_nfrags);
1289 TAILQ_FIRST(&V_ipq[i]));
1296 VNET_LIST_RUNLOCK_NOSLEEP();
1300 * Drain off all datagram fragments.
1303 ip_drain_locked(void)
1309 for (i = 0; i < IPREASS_NHASH; i++) {
1310 while(!TAILQ_EMPTY(&V_ipq[i])) {
1311 IPSTAT_ADD(ips_fragdropped,
1312 TAILQ_FIRST(&V_ipq[i])->ipq_nfrags);
1313 ip_freef(&V_ipq[i], TAILQ_FIRST(&V_ipq[i]));
1321 VNET_ITERATOR_DECL(vnet_iter);
1323 VNET_LIST_RLOCK_NOSLEEP();
1325 VNET_FOREACH(vnet_iter) {
1326 CURVNET_SET(vnet_iter);
1331 VNET_LIST_RUNLOCK_NOSLEEP();
1335 * The protocol to be inserted into ip_protox[] must be already registered
1336 * in inetsw[], either statically or through pf_proto_register().
1339 ipproto_register(short ipproto)
1343 /* Sanity checks. */
1344 if (ipproto <= 0 || ipproto >= IPPROTO_MAX)
1345 return (EPROTONOSUPPORT);
1348 * The protocol slot must not be occupied by another protocol
1349 * already. An index pointing to IPPROTO_RAW is unused.
1351 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
1353 return (EPFNOSUPPORT);
1354 if (ip_protox[ipproto] != pr - inetsw) /* IPPROTO_RAW */
1357 /* Find the protocol position in inetsw[] and set the index. */
1358 for (pr = inetdomain.dom_protosw;
1359 pr < inetdomain.dom_protoswNPROTOSW; pr++) {
1360 if (pr->pr_domain->dom_family == PF_INET &&
1361 pr->pr_protocol && pr->pr_protocol == ipproto) {
1362 ip_protox[pr->pr_protocol] = pr - inetsw;
1366 return (EPROTONOSUPPORT);
1370 ipproto_unregister(short ipproto)
1374 /* Sanity checks. */
1375 if (ipproto <= 0 || ipproto >= IPPROTO_MAX)
1376 return (EPROTONOSUPPORT);
1378 /* Check if the protocol was indeed registered. */
1379 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
1381 return (EPFNOSUPPORT);
1382 if (ip_protox[ipproto] == pr - inetsw) /* IPPROTO_RAW */
1385 /* Reset the protocol slot to IPPROTO_RAW. */
1386 ip_protox[ipproto] = pr - inetsw;
1391 * Given address of next destination (final or next hop), return (referenced)
1392 * internet address info of interface to be used to get there.
1395 ip_rtaddr(struct in_addr dst, u_int fibnum)
1398 struct sockaddr_in *sin;
1399 struct in_ifaddr *ia;
1401 bzero(&sro, sizeof(sro));
1402 sin = (struct sockaddr_in *)&sro.ro_dst;
1403 sin->sin_family = AF_INET;
1404 sin->sin_len = sizeof(*sin);
1405 sin->sin_addr = dst;
1406 in_rtalloc_ign(&sro, 0, fibnum);
1408 if (sro.ro_rt == NULL)
1411 ia = ifatoia(sro.ro_rt->rt_ifa);
1412 ifa_ref(&ia->ia_ifa);
1417 u_char inetctlerrmap[PRC_NCMDS] = {
1419 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
1420 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
1421 EMSGSIZE, EHOSTUNREACH, 0, 0,
1422 0, 0, EHOSTUNREACH, 0,
1423 ENOPROTOOPT, ECONNREFUSED
1427 * Forward a packet. If some error occurs return the sender
1428 * an icmp packet. Note we can't always generate a meaningful
1429 * icmp message because icmp doesn't have a large enough repertoire
1430 * of codes and types.
1432 * If not forwarding, just drop the packet. This could be confusing
1433 * if ipforwarding was zero but some routing protocol was advancing
1434 * us as a gateway to somewhere. However, we must let the routing
1435 * protocol deal with that.
1437 * The srcrt parameter indicates whether the packet is being forwarded
1438 * via a source route.
1441 ip_forward(struct mbuf *m, int srcrt)
1443 struct ip *ip = mtod(m, struct ip *);
1444 struct in_ifaddr *ia;
1446 struct in_addr dest;
1448 int error, type = 0, code = 0, mtu = 0;
1450 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
1451 IPSTAT_INC(ips_cantforward);
1458 if (ip->ip_ttl <= IPTTLDEC) {
1459 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS,
1467 ia = ip_rtaddr(ip->ip_dst, M_GETFIB(m));
1470 * 'ia' may be NULL if there is no route for this destination.
1471 * In case of IPsec, Don't discard it just yet, but pass it to
1472 * ip_output in case of outgoing IPsec policy.
1474 if (!srcrt && ia == NULL) {
1475 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
1481 * Save the IP header and at most 8 bytes of the payload,
1482 * in case we need to generate an ICMP message to the src.
1484 * XXX this can be optimized a lot by saving the data in a local
1485 * buffer on the stack (72 bytes at most), and only allocating the
1486 * mbuf if really necessary. The vast majority of the packets
1487 * are forwarded without having to send an ICMP back (either
1488 * because unnecessary, or because rate limited), so we are
1489 * really we are wasting a lot of work here.
1491 * We don't use m_copy() because it might return a reference
1492 * to a shared cluster. Both this function and ip_output()
1493 * assume exclusive access to the IP header in `m', so any
1494 * data in a cluster may change before we reach icmp_error().
1496 mcopy = m_gethdr(M_NOWAIT, m->m_type);
1497 if (mcopy != NULL && !m_dup_pkthdr(mcopy, m, M_NOWAIT)) {
1499 * It's probably ok if the pkthdr dup fails (because
1500 * the deep copy of the tag chain failed), but for now
1501 * be conservative and just discard the copy since
1502 * code below may some day want the tags.
1507 if (mcopy != NULL) {
1508 mcopy->m_len = min(ntohs(ip->ip_len), M_TRAILINGSPACE(mcopy));
1509 mcopy->m_pkthdr.len = mcopy->m_len;
1510 m_copydata(m, 0, mcopy->m_len, mtod(mcopy, caddr_t));
1516 ip->ip_ttl -= IPTTLDEC;
1522 * If forwarding packet using same interface that it came in on,
1523 * perhaps should send a redirect to sender to shortcut a hop.
1524 * Only send redirect if source is sending directly to us,
1525 * and if packet was not source routed (or has any options).
1526 * Also, don't send redirect if forwarding using a default route
1527 * or a route modified by a redirect.
1530 if (!srcrt && V_ipsendredirects &&
1531 ia != NULL && ia->ia_ifp == m->m_pkthdr.rcvif) {
1532 struct sockaddr_in *sin;
1535 bzero(&ro, sizeof(ro));
1536 sin = (struct sockaddr_in *)&ro.ro_dst;
1537 sin->sin_family = AF_INET;
1538 sin->sin_len = sizeof(*sin);
1539 sin->sin_addr = ip->ip_dst;
1540 in_rtalloc_ign(&ro, 0, M_GETFIB(m));
1544 if (rt && (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
1545 satosin(rt_key(rt))->sin_addr.s_addr != 0) {
1546 #define RTA(rt) ((struct in_ifaddr *)(rt->rt_ifa))
1547 u_long src = ntohl(ip->ip_src.s_addr);
1550 (src & RTA(rt)->ia_subnetmask) == RTA(rt)->ia_subnet) {
1551 if (rt->rt_flags & RTF_GATEWAY)
1552 dest.s_addr = satosin(rt->rt_gateway)->sin_addr.s_addr;
1554 dest.s_addr = ip->ip_dst.s_addr;
1555 /* Router requirements says to only send host redirects */
1556 type = ICMP_REDIRECT;
1557 code = ICMP_REDIRECT_HOST;
1565 * Try to cache the route MTU from ip_output so we can consider it for
1566 * the ICMP_UNREACH_NEEDFRAG "Next-Hop MTU" field described in RFC1191.
1568 bzero(&ro, sizeof(ro));
1570 error = ip_output(m, NULL, &ro, IP_FORWARDING, NULL, NULL);
1572 if (error == EMSGSIZE && ro.ro_rt)
1573 mtu = ro.ro_rt->rt_mtu;
1577 IPSTAT_INC(ips_cantforward);
1579 IPSTAT_INC(ips_forward);
1581 IPSTAT_INC(ips_redirectsent);
1586 ifa_free(&ia->ia_ifa);
1590 if (mcopy == NULL) {
1592 ifa_free(&ia->ia_ifa);
1598 case 0: /* forwarded, but need redirect */
1599 /* type, code set above */
1607 type = ICMP_UNREACH;
1608 code = ICMP_UNREACH_HOST;
1612 type = ICMP_UNREACH;
1613 code = ICMP_UNREACH_NEEDFRAG;
1617 * If IPsec is configured for this path,
1618 * override any possibly mtu value set by ip_output.
1620 mtu = ip_ipsec_mtu(mcopy, mtu);
1623 * If the MTU was set before make sure we are below the
1625 * If the MTU wasn't set before use the interface mtu or
1626 * fall back to the next smaller mtu step compared to the
1627 * current packet size.
1631 mtu = min(mtu, ia->ia_ifp->if_mtu);
1634 mtu = ia->ia_ifp->if_mtu;
1636 mtu = ip_next_mtu(ntohs(ip->ip_len), 0);
1638 IPSTAT_INC(ips_cantfrag);
1642 case EACCES: /* ipfw denied packet */
1645 ifa_free(&ia->ia_ifa);
1649 ifa_free(&ia->ia_ifa);
1650 icmp_error(mcopy, type, code, dest.s_addr, mtu);
1654 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
1658 if (inp->inp_socket->so_options & (SO_BINTIME | SO_TIMESTAMP)) {
1662 if (inp->inp_socket->so_options & SO_BINTIME) {
1663 *mp = sbcreatecontrol((caddr_t)&bt, sizeof(bt),
1664 SCM_BINTIME, SOL_SOCKET);
1666 mp = &(*mp)->m_next;
1668 if (inp->inp_socket->so_options & SO_TIMESTAMP) {
1671 bintime2timeval(&bt, &tv);
1672 *mp = sbcreatecontrol((caddr_t)&tv, sizeof(tv),
1673 SCM_TIMESTAMP, SOL_SOCKET);
1675 mp = &(*mp)->m_next;
1678 if (inp->inp_flags & INP_RECVDSTADDR) {
1679 *mp = sbcreatecontrol((caddr_t)&ip->ip_dst,
1680 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
1682 mp = &(*mp)->m_next;
1684 if (inp->inp_flags & INP_RECVTTL) {
1685 *mp = sbcreatecontrol((caddr_t)&ip->ip_ttl,
1686 sizeof(u_char), IP_RECVTTL, IPPROTO_IP);
1688 mp = &(*mp)->m_next;
1692 * Moving these out of udp_input() made them even more broken
1693 * than they already were.
1695 /* options were tossed already */
1696 if (inp->inp_flags & INP_RECVOPTS) {
1697 *mp = sbcreatecontrol((caddr_t)opts_deleted_above,
1698 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP);
1700 mp = &(*mp)->m_next;
1702 /* ip_srcroute doesn't do what we want here, need to fix */
1703 if (inp->inp_flags & INP_RECVRETOPTS) {
1704 *mp = sbcreatecontrol((caddr_t)ip_srcroute(m),
1705 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP);
1707 mp = &(*mp)->m_next;
1710 if (inp->inp_flags & INP_RECVIF) {
1713 struct sockaddr_dl sdl;
1716 struct sockaddr_dl *sdp;
1717 struct sockaddr_dl *sdl2 = &sdlbuf.sdl;
1719 if ((ifp = m->m_pkthdr.rcvif) &&
1720 ifp->if_index && ifp->if_index <= V_if_index) {
1721 sdp = (struct sockaddr_dl *)ifp->if_addr->ifa_addr;
1723 * Change our mind and don't try copy.
1725 if (sdp->sdl_family != AF_LINK ||
1726 sdp->sdl_len > sizeof(sdlbuf)) {
1729 bcopy(sdp, sdl2, sdp->sdl_len);
1733 offsetof(struct sockaddr_dl, sdl_data[0]);
1734 sdl2->sdl_family = AF_LINK;
1735 sdl2->sdl_index = 0;
1736 sdl2->sdl_nlen = sdl2->sdl_alen = sdl2->sdl_slen = 0;
1738 *mp = sbcreatecontrol((caddr_t)sdl2, sdl2->sdl_len,
1739 IP_RECVIF, IPPROTO_IP);
1741 mp = &(*mp)->m_next;
1743 if (inp->inp_flags & INP_RECVTOS) {
1744 *mp = sbcreatecontrol((caddr_t)&ip->ip_tos,
1745 sizeof(u_char), IP_RECVTOS, IPPROTO_IP);
1747 mp = &(*mp)->m_next;
1750 if (inp->inp_flags2 & INP_RECVFLOWID) {
1751 uint32_t flowid, flow_type;
1753 flowid = m->m_pkthdr.flowid;
1754 flow_type = M_HASHTYPE_GET(m);
1757 * XXX should handle the failure of one or the
1758 * other - don't populate both?
1760 *mp = sbcreatecontrol((caddr_t) &flowid,
1761 sizeof(uint32_t), IP_FLOWID, IPPROTO_IP);
1763 mp = &(*mp)->m_next;
1764 *mp = sbcreatecontrol((caddr_t) &flow_type,
1765 sizeof(uint32_t), IP_FLOWTYPE, IPPROTO_IP);
1767 mp = &(*mp)->m_next;
1771 if (inp->inp_flags2 & INP_RECVRSSBUCKETID) {
1772 uint32_t flowid, flow_type;
1773 uint32_t rss_bucketid;
1775 flowid = m->m_pkthdr.flowid;
1776 flow_type = M_HASHTYPE_GET(m);
1778 if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) {
1779 *mp = sbcreatecontrol((caddr_t) &rss_bucketid,
1780 sizeof(uint32_t), IP_RSSBUCKETID, IPPROTO_IP);
1782 mp = &(*mp)->m_next;
1789 * XXXRW: Multicast routing code in ip_mroute.c is generally MPSAFE, but the
1790 * ip_rsvp and ip_rsvp_on variables need to be interlocked with rsvp_on
1791 * locking. This code remains in ip_input.c as ip_mroute.c is optionally
1794 static VNET_DEFINE(int, ip_rsvp_on);
1795 VNET_DEFINE(struct socket *, ip_rsvpd);
1797 #define V_ip_rsvp_on VNET(ip_rsvp_on)
1800 ip_rsvp_init(struct socket *so)
1803 if (so->so_type != SOCK_RAW ||
1804 so->so_proto->pr_protocol != IPPROTO_RSVP)
1807 if (V_ip_rsvpd != NULL)
1812 * This may seem silly, but we need to be sure we don't over-increment
1813 * the RSVP counter, in case something slips up.
1815 if (!V_ip_rsvp_on) {
1829 * This may seem silly, but we need to be sure we don't over-decrement
1830 * the RSVP counter, in case something slips up.
1840 rsvp_input(struct mbuf **mp, int *offp, int proto)
1847 if (rsvp_input_p) { /* call the real one if loaded */
1849 rsvp_input_p(mp, offp, proto);
1850 return (IPPROTO_DONE);
1853 /* Can still get packets with rsvp_on = 0 if there is a local member
1854 * of the group to which the RSVP packet is addressed. But in this
1855 * case we want to throw the packet away.
1860 return (IPPROTO_DONE);
1863 if (V_ip_rsvpd != NULL) {
1865 rip_input(mp, offp, proto);
1866 return (IPPROTO_DONE);
1868 /* Drop the packet */
1870 return (IPPROTO_DONE);