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)
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
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"
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/callout.h>
46 #include <sys/malloc.h>
47 #include <sys/domain.h>
48 #include <sys/protosw.h>
49 #include <sys/socket.h>
51 #include <sys/kernel.h>
52 #include <sys/syslog.h>
53 #include <sys/sysctl.h>
54 #include <sys/vimage.h>
58 #include <net/if_types.h>
59 #include <net/if_var.h>
60 #include <net/if_dl.h>
61 #include <net/route.h>
62 #include <net/netisr.h>
64 #include <netinet/in.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/in_var.h>
67 #include <netinet/ip.h>
68 #include <netinet/in_pcb.h>
69 #include <netinet/ip_var.h>
70 #include <netinet/ip_icmp.h>
71 #include <netinet/ip_options.h>
72 #include <machine/in_cksum.h>
74 #include <netinet/ip_carp.h>
77 #include <netinet/ip_ipsec.h>
80 #include <sys/socketvar.h>
82 /* XXX: Temporary until ipfw_ether and ipfw_bridge are converted. */
83 #include <netinet/ip_fw.h>
84 #include <netinet/ip_dummynet.h>
86 #include <security/mac/mac_framework.h>
89 CTASSERT(sizeof(struct ip) == 20);
93 static int ipsendredirects;
94 static int ip_checkinterface;
95 static int ip_keepfaith;
96 static int ip_sendsourcequench;
100 struct in_ifaddrhead in_ifaddrhead; /* first inet address */
101 struct in_ifaddrhashhead *in_ifaddrhashtbl; /* inet addr hash table */
102 u_long in_ifaddrhmask; /* mask for hash table */
103 struct ipstat ipstat;
104 static int ip_rsvp_on;
105 struct socket *ip_rsvpd;
107 static TAILQ_HEAD(ipqhead, ipq) ipq[IPREASS_NHASH];
108 static int maxnipq; /* Administrative limit on # reass queues. */
109 static int maxfragsperpacket;
111 static int nipq; /* Total # of reass queues */
114 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, IPCTL_FORWARDING,
115 forwarding, CTLFLAG_RW, ipforwarding, 0,
116 "Enable IP forwarding between interfaces");
118 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, IPCTL_SENDREDIRECTS,
119 redirect, CTLFLAG_RW, ipsendredirects, 0,
120 "Enable sending IP redirects");
122 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, IPCTL_DEFTTL,
123 ttl, CTLFLAG_RW, ip_defttl, 0, "Maximum TTL on IP packets");
125 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, IPCTL_KEEPFAITH,
126 keepfaith, CTLFLAG_RW, ip_keepfaith, 0,
127 "Enable packet capture for FAITH IPv4->IPv6 translater daemon");
129 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, OID_AUTO,
130 sendsourcequench, CTLFLAG_RW, ip_sendsourcequench, 0,
131 "Enable the transmission of source quench packets");
133 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, OID_AUTO, random_id,
134 CTLFLAG_RW, ip_do_randomid, 0, "Assign random ip_id values");
137 * XXX - Setting ip_checkinterface mostly implements the receive side of
138 * the Strong ES model described in RFC 1122, but since the routing table
139 * and transmit implementation do not implement the Strong ES model,
140 * setting this to 1 results in an odd hybrid.
142 * XXX - ip_checkinterface currently must be disabled if you use ipnat
143 * to translate the destination address to another local interface.
145 * XXX - ip_checkinterface must be disabled if you add IP aliases
146 * to the loopback interface instead of the interface where the
147 * packets for those addresses are received.
149 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, OID_AUTO,
150 check_interface, CTLFLAG_RW, ip_checkinterface, 0,
151 "Verify packet arrives on correct interface");
153 struct pfil_head inet_pfil_hook; /* Packet filter hooks */
155 static struct ifqueue ipintrq;
156 static int ipqmaxlen = IFQ_MAXLEN;
158 extern struct domain inetdomain;
159 extern struct protosw inetsw[];
160 u_char ip_protox[IPPROTO_MAX];
162 SYSCTL_INT(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen, CTLFLAG_RW,
163 &ipintrq.ifq_maxlen, 0, "Maximum size of the IP input queue");
164 SYSCTL_INT(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops, CTLFLAG_RD,
165 &ipintrq.ifq_drops, 0,
166 "Number of packets dropped from the IP input queue");
168 SYSCTL_V_STRUCT(V_NET, vnet_inet, _net_inet_ip, IPCTL_STATS, stats, CTLFLAG_RW,
169 ipstat, ipstat, "IP statistics (struct ipstat, netinet/ip_var.h)");
171 static uma_zone_t ipq_zone;
172 static struct mtx ipqlock;
174 #define IPQ_LOCK() mtx_lock(&ipqlock)
175 #define IPQ_UNLOCK() mtx_unlock(&ipqlock)
176 #define IPQ_LOCK_INIT() mtx_init(&ipqlock, "ipqlock", NULL, MTX_DEF)
177 #define IPQ_LOCK_ASSERT() mtx_assert(&ipqlock, MA_OWNED)
179 static void maxnipq_update(void);
180 static void ipq_zone_change(void *);
182 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, OID_AUTO, fragpackets,
184 "Current number of IPv4 fragment reassembly queue entries");
186 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, OID_AUTO, maxfragsperpacket,
187 CTLFLAG_RW, maxfragsperpacket, 0,
188 "Maximum number of IPv4 fragments allowed per packet");
190 struct callout ipport_tick_callout;
193 SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW,
194 &ip_mtu, 0, "Default MTU");
198 SYSCTL_V_INT(V_NET, vnet_inet, _net_inet_ip, OID_AUTO, stealth, CTLFLAG_RW,
199 ipstealth, 0, "IP stealth mode, no TTL decrementation on forwarding");
203 * ipfw_ether and ipfw_bridge hooks.
204 * XXX: Temporary until those are converted to pfil_hooks as well.
206 ip_fw_chk_t *ip_fw_chk_ptr = NULL;
207 ip_dn_io_t *ip_dn_io_ptr = NULL;
210 static void ip_freef(struct ipqhead *, struct ipq *);
213 * IP initialization: fill in IP protocol switch table.
214 * All protocols not implemented in kernel go to raw IP protocol handler.
219 INIT_VNET_INET(curvnet);
223 V_ipsendredirects = 1; /* XXX */
224 V_ip_checkinterface = 0;
226 V_ip_sendsourcequench = 0;
228 V_ip_defttl = IPDEFTTL;
229 V_ip_do_randomid = 0;
232 V_nipq = 0; /* Total # of reass queues */
234 V_ipport_lowfirstauto = IPPORT_RESERVED - 1; /* 1023 */
235 V_ipport_lowlastauto = IPPORT_RESERVEDSTART; /* 600 */
236 V_ipport_firstauto = IPPORT_EPHEMERALFIRST; /* 10000 */
237 V_ipport_lastauto = IPPORT_EPHEMERALLAST; /* 65535 */
238 V_ipport_hifirstauto = IPPORT_HIFIRSTAUTO; /* 49152 */
239 V_ipport_hilastauto = IPPORT_HILASTAUTO; /* 65535 */
240 V_ipport_reservedhigh = IPPORT_RESERVED - 1; /* 1023 */
241 V_ipport_reservedlow = 0;
242 V_ipport_randomized = 1; /* user controlled via sysctl */
243 V_ipport_randomcps = 10; /* user controlled via sysctl */
244 V_ipport_randomtime = 45; /* user controlled via sysctl */
245 V_ipport_stoprandom = 0; /* toggled by ipport_tick */
248 /* XXX global static but not instantiated in this file */
249 V_ipfastforward_active = 0;
250 V_subnetsarelocal = 0;
251 V_sameprefixcarponly = 0;
254 TAILQ_INIT(&V_in_ifaddrhead);
255 V_in_ifaddrhashtbl = hashinit(INADDR_NHASH, M_IFADDR, &V_in_ifaddrhmask);
256 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
258 panic("ip_init: PF_INET not found");
260 /* Initialize the entire ip_protox[] array to IPPROTO_RAW. */
261 for (i = 0; i < IPPROTO_MAX; i++)
262 ip_protox[i] = pr - inetsw;
264 * Cycle through IP protocols and put them into the appropriate place
267 for (pr = inetdomain.dom_protosw;
268 pr < inetdomain.dom_protoswNPROTOSW; pr++)
269 if (pr->pr_domain->dom_family == PF_INET &&
270 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) {
271 /* Be careful to only index valid IP protocols. */
272 if (pr->pr_protocol < IPPROTO_MAX)
273 ip_protox[pr->pr_protocol] = pr - inetsw;
276 /* Initialize packet filter hooks. */
277 inet_pfil_hook.ph_type = PFIL_TYPE_AF;
278 inet_pfil_hook.ph_af = AF_INET;
279 if ((i = pfil_head_register(&inet_pfil_hook)) != 0)
280 printf("%s: WARNING: unable to register pfil hook, "
281 "error %d\n", __func__, i);
283 /* Initialize IP reassembly queue. */
285 for (i = 0; i < IPREASS_NHASH; i++)
286 TAILQ_INIT(&V_ipq[i]);
287 V_maxnipq = nmbclusters / 32;
288 V_maxfragsperpacket = 16;
289 V_ipq_zone = uma_zcreate("ipq", sizeof(struct ipq), NULL, NULL, NULL,
290 NULL, UMA_ALIGN_PTR, 0);
293 /* Start ipport_tick. */
294 callout_init(&ipport_tick_callout, CALLOUT_MPSAFE);
296 EVENTHANDLER_REGISTER(shutdown_pre_sync, ip_fini, NULL,
297 SHUTDOWN_PRI_DEFAULT);
298 EVENTHANDLER_REGISTER(nmbclusters_change, ipq_zone_change,
299 NULL, EVENTHANDLER_PRI_ANY);
301 /* Initialize various other remaining things. */
302 V_ip_id = time_second & 0xffff;
303 ipintrq.ifq_maxlen = ipqmaxlen;
304 mtx_init(&ipintrq.ifq_mtx, "ip_inq", NULL, MTX_DEF);
305 netisr_register(NETISR_IP, ip_input, &ipintrq, 0);
312 callout_stop(&ipport_tick_callout);
316 * Ip input routine. Checksum and byte swap header. If fragmented
317 * try to reassemble. Process options. Pass to next level.
320 ip_input(struct mbuf *m)
322 INIT_VNET_INET(curvnet);
323 struct ip *ip = NULL;
324 struct in_ifaddr *ia = NULL;
326 int checkif, hlen = 0;
328 int dchg = 0; /* dest changed after fw */
329 struct in_addr odst; /* original dst address */
333 if (m->m_flags & M_FASTFWD_OURS) {
335 * Firewall or NAT changed destination to local.
336 * We expect ip_len and ip_off to be in host byte order.
338 m->m_flags &= ~M_FASTFWD_OURS;
339 /* Set up some basics that will be used later. */
340 ip = mtod(m, struct ip *);
341 hlen = ip->ip_hl << 2;
345 V_ipstat.ips_total++;
347 if (m->m_pkthdr.len < sizeof(struct ip))
350 if (m->m_len < sizeof (struct ip) &&
351 (m = m_pullup(m, sizeof (struct ip))) == NULL) {
352 V_ipstat.ips_toosmall++;
355 ip = mtod(m, struct ip *);
357 if (ip->ip_v != IPVERSION) {
358 V_ipstat.ips_badvers++;
362 hlen = ip->ip_hl << 2;
363 if (hlen < sizeof(struct ip)) { /* minimum header length */
364 V_ipstat.ips_badhlen++;
367 if (hlen > m->m_len) {
368 if ((m = m_pullup(m, hlen)) == NULL) {
369 V_ipstat.ips_badhlen++;
372 ip = mtod(m, struct ip *);
375 /* 127/8 must not appear on wire - RFC1122 */
376 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
377 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
378 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) {
379 V_ipstat.ips_badaddr++;
384 if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) {
385 sum = !(m->m_pkthdr.csum_flags & CSUM_IP_VALID);
387 if (hlen == sizeof(struct ip)) {
388 sum = in_cksum_hdr(ip);
390 sum = in_cksum(m, hlen);
394 V_ipstat.ips_badsum++;
399 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0)
400 /* packet is dropped by traffic conditioner */
405 * Convert fields to host representation.
407 ip->ip_len = ntohs(ip->ip_len);
408 if (ip->ip_len < hlen) {
409 V_ipstat.ips_badlen++;
412 ip->ip_off = ntohs(ip->ip_off);
415 * Check that the amount of data in the buffers
416 * is as at least much as the IP header would have us expect.
417 * Trim mbufs if longer than we expect.
418 * Drop packet if shorter than we expect.
420 if (m->m_pkthdr.len < ip->ip_len) {
422 V_ipstat.ips_tooshort++;
425 if (m->m_pkthdr.len > ip->ip_len) {
426 if (m->m_len == m->m_pkthdr.len) {
427 m->m_len = ip->ip_len;
428 m->m_pkthdr.len = ip->ip_len;
430 m_adj(m, ip->ip_len - m->m_pkthdr.len);
434 * Bypass packet filtering for packets from a tunnel (gif).
436 if (ip_ipsec_filtertunnel(m))
441 * Run through list of hooks for input packets.
443 * NB: Beware of the destination address changing (e.g.
444 * by NAT rewriting). When this happens, tell
445 * ip_forward to do the right thing.
448 /* Jump over all PFIL processing if hooks are not active. */
449 if (!PFIL_HOOKED(&inet_pfil_hook))
453 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif,
456 if (m == NULL) /* consumed by filter */
459 ip = mtod(m, struct ip *);
460 dchg = (odst.s_addr != ip->ip_dst.s_addr);
462 #ifdef IPFIREWALL_FORWARD
463 if (m->m_flags & M_FASTFWD_OURS) {
464 m->m_flags &= ~M_FASTFWD_OURS;
467 if ((dchg = (m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL)) != 0) {
469 * Directly ship on the packet. This allows to forward packets
470 * that were destined for us to some other directly connected
476 #endif /* IPFIREWALL_FORWARD */
480 * Process options and, if not destined for us,
481 * ship it on. ip_dooptions returns 1 when an
482 * error was detected (causing an icmp message
483 * to be sent and the original packet to be freed).
485 if (hlen > sizeof (struct ip) && ip_dooptions(m, 0))
488 /* greedy RSVP, snatches any PATH packet of the RSVP protocol and no
489 * matter if it is destined to another node, or whether it is
490 * a multicast one, RSVP wants it! and prevents it from being forwarded
491 * anywhere else. Also checks if the rsvp daemon is running before
492 * grabbing the packet.
494 if (V_rsvp_on && ip->ip_p==IPPROTO_RSVP)
498 * Check our list of addresses, to see if the packet is for us.
499 * If we don't have any addresses, assume any unicast packet
500 * we receive might be for us (and let the upper layers deal
503 if (TAILQ_EMPTY(&V_in_ifaddrhead) &&
504 (m->m_flags & (M_MCAST|M_BCAST)) == 0)
508 * Enable a consistency check between the destination address
509 * and the arrival interface for a unicast packet (the RFC 1122
510 * strong ES model) if IP forwarding is disabled and the packet
511 * is not locally generated and the packet is not subject to
514 * XXX - Checking also should be disabled if the destination
515 * address is ipnat'ed to a different interface.
517 * XXX - Checking is incompatible with IP aliases added
518 * to the loopback interface instead of the interface where
519 * the packets are received.
521 * XXX - This is the case for carp vhost IPs as well so we
522 * insert a workaround. If the packet got here, we already
523 * checked with carp_iamatch() and carp_forus().
525 checkif = V_ip_checkinterface && (V_ipforwarding == 0) &&
526 m->m_pkthdr.rcvif != NULL &&
527 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) &&
529 !m->m_pkthdr.rcvif->if_carp &&
534 * Check for exact addresses in the hash bucket.
536 LIST_FOREACH(ia, INADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
538 * If the address matches, verify that the packet
539 * arrived via the correct interface if checking is
542 if (IA_SIN(ia)->sin_addr.s_addr == ip->ip_dst.s_addr &&
543 (!checkif || ia->ia_ifp == m->m_pkthdr.rcvif))
547 * Check for broadcast addresses.
549 * Only accept broadcast packets that arrive via the matching
550 * interface. Reception of forwarded directed broadcasts would
551 * be handled via ip_forward() and ether_output() with the loopback
552 * into the stack for SIMPLEX interfaces handled by ether_output().
554 if (m->m_pkthdr.rcvif != NULL &&
555 m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) {
556 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrhead, ifa_link) {
557 if (ifa->ifa_addr->sa_family != AF_INET)
560 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr ==
563 if (ia->ia_netbroadcast.s_addr == ip->ip_dst.s_addr)
566 if (IA_SIN(ia)->sin_addr.s_addr == INADDR_ANY)
571 /* RFC 3927 2.7: Do not forward datagrams for 169.254.0.0/16. */
572 if (IN_LINKLOCAL(ntohl(ip->ip_dst.s_addr))) {
573 V_ipstat.ips_cantforward++;
577 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
578 struct in_multi *inm;
581 * If we are acting as a multicast router, all
582 * incoming multicast packets are passed to the
583 * kernel-level multicast forwarding function.
584 * The packet is returned (relatively) intact; if
585 * ip_mforward() returns a non-zero value, the packet
586 * must be discarded, else it may be accepted below.
589 ip_mforward(ip, m->m_pkthdr.rcvif, m, 0) != 0) {
590 V_ipstat.ips_cantforward++;
596 * The process-level routing daemon needs to receive
597 * all multicast IGMP packets, whether or not this
598 * host belongs to their destination groups.
600 if (ip->ip_p == IPPROTO_IGMP)
602 V_ipstat.ips_forward++;
605 * See if we belong to the destination multicast group on the
609 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm);
612 V_ipstat.ips_notmember++;
618 if (ip->ip_dst.s_addr == (u_long)INADDR_BROADCAST)
620 if (ip->ip_dst.s_addr == INADDR_ANY)
624 * FAITH(Firewall Aided Internet Translator)
626 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) {
627 if (V_ip_keepfaith) {
628 if (ip->ip_p == IPPROTO_TCP || ip->ip_p == IPPROTO_ICMP)
636 * Not for us; forward if possible and desirable.
638 if (V_ipforwarding == 0) {
639 V_ipstat.ips_cantforward++;
653 * IPSTEALTH: Process non-routing options only
654 * if the packet is destined for us.
656 if (V_ipstealth && hlen > sizeof (struct ip) &&
659 #endif /* IPSTEALTH */
661 /* Count the packet in the ip address stats */
663 ia->ia_ifa.if_ipackets++;
664 ia->ia_ifa.if_ibytes += m->m_pkthdr.len;
668 * Attempt reassembly; if it succeeds, proceed.
669 * ip_reass() will return a different mbuf.
671 if (ip->ip_off & (IP_MF | IP_OFFMASK)) {
675 ip = mtod(m, struct ip *);
676 /* Get the header length of the reassembled packet */
677 hlen = ip->ip_hl << 2;
681 * Further protocols expect the packet length to be w/o the
688 * enforce IPsec policy checking if we are seeing last header.
689 * note that we do not visit this with protocols with pcb layer
690 * code - like udp/tcp/raw ip.
692 if (ip_ipsec_input(m))
697 * Switch out to protocol's input routine.
699 V_ipstat.ips_delivered++;
701 (*inetsw[ip_protox[ip->ip_p]].pr_input)(m, hlen);
708 * After maxnipq has been updated, propagate the change to UMA. The UMA zone
709 * max has slightly different semantics than the sysctl, for historical
715 INIT_VNET_INET(curvnet);
718 * -1 for unlimited allocation.
721 uma_zone_set_max(V_ipq_zone, 0);
723 * Positive number for specific bound.
726 uma_zone_set_max(V_ipq_zone, V_maxnipq);
728 * Zero specifies no further fragment queue allocation -- set the
729 * bound very low, but rely on implementation elsewhere to actually
730 * prevent allocation and reclaim current queues.
733 uma_zone_set_max(V_ipq_zone, 1);
737 ipq_zone_change(void *tag)
739 INIT_VNET_INET(curvnet);
741 if (V_maxnipq > 0 && V_maxnipq < (nmbclusters / 32)) {
742 V_maxnipq = nmbclusters / 32;
748 sysctl_maxnipq(SYSCTL_HANDLER_ARGS)
750 INIT_VNET_INET(curvnet);
754 error = sysctl_handle_int(oidp, &i, 0, req);
755 if (error || !req->newptr)
759 * XXXRW: Might be a good idea to sanity check the argument and place
760 * an extreme upper bound.
769 SYSCTL_PROC(_net_inet_ip, OID_AUTO, maxfragpackets, CTLTYPE_INT|CTLFLAG_RW,
770 NULL, 0, sysctl_maxnipq, "I",
771 "Maximum number of IPv4 fragment reassembly queue entries");
774 * Take incoming datagram fragment and try to reassemble it into
775 * whole datagram. If the argument is the first fragment or one
776 * in between the function will return NULL and store the mbuf
777 * in the fragment chain. If the argument is the last fragment
778 * the packet will be reassembled and the pointer to the new
779 * mbuf returned for further processing. Only m_tags attached
780 * to the first packet/fragment are preserved.
781 * The IP header is *NOT* adjusted out of iplen.
784 ip_reass(struct mbuf *m)
786 INIT_VNET_INET(curvnet);
788 struct mbuf *p, *q, *nq, *t;
789 struct ipq *fp = NULL;
790 struct ipqhead *head;
795 /* If maxnipq or maxfragsperpacket are 0, never accept fragments. */
796 if (V_maxnipq == 0 || V_maxfragsperpacket == 0) {
797 V_ipstat.ips_fragments++;
798 V_ipstat.ips_fragdropped++;
803 ip = mtod(m, struct ip *);
804 hlen = ip->ip_hl << 2;
806 hash = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id);
811 * Look for queue of fragments
814 TAILQ_FOREACH(fp, head, ipq_list)
815 if (ip->ip_id == fp->ipq_id &&
816 ip->ip_src.s_addr == fp->ipq_src.s_addr &&
817 ip->ip_dst.s_addr == fp->ipq_dst.s_addr &&
819 mac_ipq_match(m, fp) &&
821 ip->ip_p == fp->ipq_p)
827 * Attempt to trim the number of allocated fragment queues if it
828 * exceeds the administrative limit.
830 if ((V_nipq > V_maxnipq) && (V_maxnipq > 0)) {
832 * drop something from the tail of the current queue
833 * before proceeding further
835 struct ipq *q = TAILQ_LAST(head, ipqhead);
836 if (q == NULL) { /* gak */
837 for (i = 0; i < IPREASS_NHASH; i++) {
838 struct ipq *r = TAILQ_LAST(&V_ipq[i], ipqhead);
840 V_ipstat.ips_fragtimeout +=
842 ip_freef(&V_ipq[i], r);
847 V_ipstat.ips_fragtimeout += q->ipq_nfrags;
854 * Adjust ip_len to not reflect header,
855 * convert offset of this to bytes.
858 if (ip->ip_off & IP_MF) {
860 * Make sure that fragments have a data length
861 * that's a non-zero multiple of 8 bytes.
863 if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) {
864 V_ipstat.ips_toosmall++; /* XXX */
867 m->m_flags |= M_FRAG;
869 m->m_flags &= ~M_FRAG;
874 * Attempt reassembly; if it succeeds, proceed.
875 * ip_reass() will return a different mbuf.
877 V_ipstat.ips_fragments++;
878 m->m_pkthdr.header = ip;
880 /* Previous ip_reass() started here. */
882 * Presence of header sizes in mbufs
883 * would confuse code below.
889 * If first fragment to arrive, create a reassembly queue.
892 fp = uma_zalloc(V_ipq_zone, M_NOWAIT);
896 if (mac_ipq_init(fp, M_NOWAIT) != 0) {
897 uma_zfree(V_ipq_zone, fp);
901 mac_ipq_create(m, fp);
903 TAILQ_INSERT_HEAD(head, fp, ipq_list);
906 fp->ipq_ttl = IPFRAGTTL;
907 fp->ipq_p = ip->ip_p;
908 fp->ipq_id = ip->ip_id;
909 fp->ipq_src = ip->ip_src;
910 fp->ipq_dst = ip->ip_dst;
917 mac_ipq_update(m, fp);
921 #define GETIP(m) ((struct ip*)((m)->m_pkthdr.header))
924 * Handle ECN by comparing this segment with the first one;
925 * if CE is set, do not lose CE.
926 * drop if CE and not-ECT are mixed for the same packet.
928 ecn = ip->ip_tos & IPTOS_ECN_MASK;
929 ecn0 = GETIP(fp->ipq_frags)->ip_tos & IPTOS_ECN_MASK;
930 if (ecn == IPTOS_ECN_CE) {
931 if (ecn0 == IPTOS_ECN_NOTECT)
933 if (ecn0 != IPTOS_ECN_CE)
934 GETIP(fp->ipq_frags)->ip_tos |= IPTOS_ECN_CE;
936 if (ecn == IPTOS_ECN_NOTECT && ecn0 != IPTOS_ECN_NOTECT)
940 * Find a segment which begins after this one does.
942 for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt)
943 if (GETIP(q)->ip_off > ip->ip_off)
947 * If there is a preceding segment, it may provide some of
948 * our data already. If so, drop the data from the incoming
949 * segment. If it provides all of our data, drop us, otherwise
950 * stick new segment in the proper place.
952 * If some of the data is dropped from the the preceding
953 * segment, then it's checksum is invalidated.
956 i = GETIP(p)->ip_off + GETIP(p)->ip_len - ip->ip_off;
961 m->m_pkthdr.csum_flags = 0;
965 m->m_nextpkt = p->m_nextpkt;
968 m->m_nextpkt = fp->ipq_frags;
973 * While we overlap succeeding segments trim them or,
974 * if they are completely covered, dequeue them.
976 for (; q != NULL && ip->ip_off + ip->ip_len > GETIP(q)->ip_off;
978 i = (ip->ip_off + ip->ip_len) - GETIP(q)->ip_off;
979 if (i < GETIP(q)->ip_len) {
980 GETIP(q)->ip_len -= i;
981 GETIP(q)->ip_off += i;
983 q->m_pkthdr.csum_flags = 0;
988 V_ipstat.ips_fragdropped++;
994 * Check for complete reassembly and perform frag per packet
997 * Frag limiting is performed here so that the nth frag has
998 * a chance to complete the packet before we drop the packet.
999 * As a result, n+1 frags are actually allowed per packet, but
1000 * only n will ever be stored. (n = maxfragsperpacket.)
1004 for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt) {
1005 if (GETIP(q)->ip_off != next) {
1006 if (fp->ipq_nfrags > V_maxfragsperpacket) {
1007 V_ipstat.ips_fragdropped += fp->ipq_nfrags;
1012 next += GETIP(q)->ip_len;
1014 /* Make sure the last packet didn't have the IP_MF flag */
1015 if (p->m_flags & M_FRAG) {
1016 if (fp->ipq_nfrags > V_maxfragsperpacket) {
1017 V_ipstat.ips_fragdropped += fp->ipq_nfrags;
1024 * Reassembly is complete. Make sure the packet is a sane size.
1028 if (next + (ip->ip_hl << 2) > IP_MAXPACKET) {
1029 V_ipstat.ips_toolong++;
1030 V_ipstat.ips_fragdropped += fp->ipq_nfrags;
1036 * Concatenate fragments.
1043 q->m_nextpkt = NULL;
1044 for (q = nq; q != NULL; q = nq) {
1046 q->m_nextpkt = NULL;
1047 m->m_pkthdr.csum_flags &= q->m_pkthdr.csum_flags;
1048 m->m_pkthdr.csum_data += q->m_pkthdr.csum_data;
1052 * In order to do checksumming faster we do 'end-around carry' here
1053 * (and not in for{} loop), though it implies we are not going to
1054 * reassemble more than 64k fragments.
1056 m->m_pkthdr.csum_data =
1057 (m->m_pkthdr.csum_data & 0xffff) + (m->m_pkthdr.csum_data >> 16);
1059 mac_ipq_reassemble(fp, m);
1060 mac_ipq_destroy(fp);
1064 * Create header for new ip packet by modifying header of first
1065 * packet; dequeue and discard fragment reassembly header.
1066 * Make header visible.
1068 ip->ip_len = (ip->ip_hl << 2) + next;
1069 ip->ip_src = fp->ipq_src;
1070 ip->ip_dst = fp->ipq_dst;
1071 TAILQ_REMOVE(head, fp, ipq_list);
1073 uma_zfree(V_ipq_zone, fp);
1074 m->m_len += (ip->ip_hl << 2);
1075 m->m_data -= (ip->ip_hl << 2);
1076 /* some debugging cruft by sklower, below, will go away soon */
1077 if (m->m_flags & M_PKTHDR) /* XXX this should be done elsewhere */
1079 V_ipstat.ips_reassembled++;
1084 V_ipstat.ips_fragdropped++;
1096 * Free a fragment reassembly header and all
1097 * associated datagrams.
1100 ip_freef(struct ipqhead *fhp, struct ipq *fp)
1102 INIT_VNET_INET(curvnet);
1107 while (fp->ipq_frags) {
1109 fp->ipq_frags = q->m_nextpkt;
1112 TAILQ_REMOVE(fhp, fp, ipq_list);
1113 uma_zfree(V_ipq_zone, fp);
1118 * IP timer processing;
1119 * if a timer expires on a reassembly
1120 * queue, discard it.
1125 VNET_ITERATOR_DECL(vnet_iter);
1131 VNET_FOREACH(vnet_iter) {
1132 CURVNET_SET(vnet_iter);
1133 INIT_VNET_INET(vnet_iter);
1134 for (i = 0; i < IPREASS_NHASH; i++) {
1135 for(fp = TAILQ_FIRST(&V_ipq[i]); fp;) {
1139 fp = TAILQ_NEXT(fp, ipq_list);
1140 if(--fpp->ipq_ttl == 0) {
1141 V_ipstat.ips_fragtimeout +=
1143 ip_freef(&V_ipq[i], fpp);
1148 * If we are over the maximum number of fragments
1149 * (due to the limit being lowered), drain off
1150 * enough to get down to the new limit.
1152 if (V_maxnipq >= 0 && V_nipq > V_maxnipq) {
1153 for (i = 0; i < IPREASS_NHASH; i++) {
1154 while (V_nipq > V_maxnipq &&
1155 !TAILQ_EMPTY(&V_ipq[i])) {
1156 V_ipstat.ips_fragdropped +=
1157 TAILQ_FIRST(&V_ipq[i])->ipq_nfrags;
1159 TAILQ_FIRST(&V_ipq[i]));
1165 VNET_LIST_RUNLOCK();
1170 * Drain off all datagram fragments.
1175 VNET_ITERATOR_DECL(vnet_iter);
1180 VNET_FOREACH(vnet_iter) {
1181 CURVNET_SET(vnet_iter);
1182 INIT_VNET_INET(vnet_iter);
1183 for (i = 0; i < IPREASS_NHASH; i++) {
1184 while(!TAILQ_EMPTY(&V_ipq[i])) {
1185 V_ipstat.ips_fragdropped +=
1186 TAILQ_FIRST(&V_ipq[i])->ipq_nfrags;
1187 ip_freef(&V_ipq[i], TAILQ_FIRST(&V_ipq[i]));
1192 VNET_LIST_RUNLOCK();
1198 * The protocol to be inserted into ip_protox[] must be already registered
1199 * in inetsw[], either statically or through pf_proto_register().
1202 ipproto_register(u_char ipproto)
1206 /* Sanity checks. */
1208 return (EPROTONOSUPPORT);
1211 * The protocol slot must not be occupied by another protocol
1212 * already. An index pointing to IPPROTO_RAW is unused.
1214 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
1216 return (EPFNOSUPPORT);
1217 if (ip_protox[ipproto] != pr - inetsw) /* IPPROTO_RAW */
1220 /* Find the protocol position in inetsw[] and set the index. */
1221 for (pr = inetdomain.dom_protosw;
1222 pr < inetdomain.dom_protoswNPROTOSW; pr++) {
1223 if (pr->pr_domain->dom_family == PF_INET &&
1224 pr->pr_protocol && pr->pr_protocol == ipproto) {
1225 /* Be careful to only index valid IP protocols. */
1226 if (pr->pr_protocol < IPPROTO_MAX) {
1227 ip_protox[pr->pr_protocol] = pr - inetsw;
1233 return (EPROTONOSUPPORT);
1237 ipproto_unregister(u_char ipproto)
1241 /* Sanity checks. */
1243 return (EPROTONOSUPPORT);
1245 /* Check if the protocol was indeed registered. */
1246 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW);
1248 return (EPFNOSUPPORT);
1249 if (ip_protox[ipproto] == pr - inetsw) /* IPPROTO_RAW */
1252 /* Reset the protocol slot to IPPROTO_RAW. */
1253 ip_protox[ipproto] = pr - inetsw;
1258 * Given address of next destination (final or next hop),
1259 * return internet address info of interface to be used to get there.
1262 ip_rtaddr(struct in_addr dst, u_int fibnum)
1265 struct sockaddr_in *sin;
1266 struct in_ifaddr *ifa;
1268 bzero(&sro, sizeof(sro));
1269 sin = (struct sockaddr_in *)&sro.ro_dst;
1270 sin->sin_family = AF_INET;
1271 sin->sin_len = sizeof(*sin);
1272 sin->sin_addr = dst;
1273 in_rtalloc_ign(&sro, RTF_CLONING, fibnum);
1275 if (sro.ro_rt == NULL)
1278 ifa = ifatoia(sro.ro_rt->rt_ifa);
1283 u_char inetctlerrmap[PRC_NCMDS] = {
1285 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
1286 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
1287 EMSGSIZE, EHOSTUNREACH, 0, 0,
1288 0, 0, EHOSTUNREACH, 0,
1289 ENOPROTOOPT, ECONNREFUSED
1293 * Forward a packet. If some error occurs return the sender
1294 * an icmp packet. Note we can't always generate a meaningful
1295 * icmp message because icmp doesn't have a large enough repertoire
1296 * of codes and types.
1298 * If not forwarding, just drop the packet. This could be confusing
1299 * if ipforwarding was zero but some routing protocol was advancing
1300 * us as a gateway to somewhere. However, we must let the routing
1301 * protocol deal with that.
1303 * The srcrt parameter indicates whether the packet is being forwarded
1304 * via a source route.
1307 ip_forward(struct mbuf *m, int srcrt)
1309 INIT_VNET_INET(curvnet);
1310 struct ip *ip = mtod(m, struct ip *);
1311 struct in_ifaddr *ia = NULL;
1313 struct in_addr dest;
1315 int error, type = 0, code = 0, mtu = 0;
1317 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) {
1318 V_ipstat.ips_cantforward++;
1325 if (ip->ip_ttl <= IPTTLDEC) {
1326 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS,
1334 ia = ip_rtaddr(ip->ip_dst, M_GETFIB(m));
1335 if (!srcrt && ia == NULL) {
1336 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
1341 * Save the IP header and at most 8 bytes of the payload,
1342 * in case we need to generate an ICMP message to the src.
1344 * XXX this can be optimized a lot by saving the data in a local
1345 * buffer on the stack (72 bytes at most), and only allocating the
1346 * mbuf if really necessary. The vast majority of the packets
1347 * are forwarded without having to send an ICMP back (either
1348 * because unnecessary, or because rate limited), so we are
1349 * really we are wasting a lot of work here.
1351 * We don't use m_copy() because it might return a reference
1352 * to a shared cluster. Both this function and ip_output()
1353 * assume exclusive access to the IP header in `m', so any
1354 * data in a cluster may change before we reach icmp_error().
1356 MGETHDR(mcopy, M_DONTWAIT, m->m_type);
1357 if (mcopy != NULL && !m_dup_pkthdr(mcopy, m, M_DONTWAIT)) {
1359 * It's probably ok if the pkthdr dup fails (because
1360 * the deep copy of the tag chain failed), but for now
1361 * be conservative and just discard the copy since
1362 * code below may some day want the tags.
1367 if (mcopy != NULL) {
1368 mcopy->m_len = min(ip->ip_len, M_TRAILINGSPACE(mcopy));
1369 mcopy->m_pkthdr.len = mcopy->m_len;
1370 m_copydata(m, 0, mcopy->m_len, mtod(mcopy, caddr_t));
1376 ip->ip_ttl -= IPTTLDEC;
1382 * If forwarding packet using same interface that it came in on,
1383 * perhaps should send a redirect to sender to shortcut a hop.
1384 * Only send redirect if source is sending directly to us,
1385 * and if packet was not source routed (or has any options).
1386 * Also, don't send redirect if forwarding using a default route
1387 * or a route modified by a redirect.
1390 if (!srcrt && V_ipsendredirects && ia->ia_ifp == m->m_pkthdr.rcvif) {
1391 struct sockaddr_in *sin;
1394 bzero(&ro, sizeof(ro));
1395 sin = (struct sockaddr_in *)&ro.ro_dst;
1396 sin->sin_family = AF_INET;
1397 sin->sin_len = sizeof(*sin);
1398 sin->sin_addr = ip->ip_dst;
1399 in_rtalloc_ign(&ro, RTF_CLONING, M_GETFIB(m));
1403 if (rt && (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 &&
1404 satosin(rt_key(rt))->sin_addr.s_addr != 0) {
1405 #define RTA(rt) ((struct in_ifaddr *)(rt->rt_ifa))
1406 u_long src = ntohl(ip->ip_src.s_addr);
1409 (src & RTA(rt)->ia_subnetmask) == RTA(rt)->ia_subnet) {
1410 if (rt->rt_flags & RTF_GATEWAY)
1411 dest.s_addr = satosin(rt->rt_gateway)->sin_addr.s_addr;
1413 dest.s_addr = ip->ip_dst.s_addr;
1414 /* Router requirements says to only send host redirects */
1415 type = ICMP_REDIRECT;
1416 code = ICMP_REDIRECT_HOST;
1424 * Try to cache the route MTU from ip_output so we can consider it for
1425 * the ICMP_UNREACH_NEEDFRAG "Next-Hop MTU" field described in RFC1191.
1427 bzero(&ro, sizeof(ro));
1429 error = ip_output(m, NULL, &ro, IP_FORWARDING, NULL, NULL);
1431 if (error == EMSGSIZE && ro.ro_rt)
1432 mtu = ro.ro_rt->rt_rmx.rmx_mtu;
1437 V_ipstat.ips_cantforward++;
1439 V_ipstat.ips_forward++;
1441 V_ipstat.ips_redirectsent++;
1453 case 0: /* forwarded, but need redirect */
1454 /* type, code set above */
1457 case ENETUNREACH: /* shouldn't happen, checked above */
1462 type = ICMP_UNREACH;
1463 code = ICMP_UNREACH_HOST;
1467 type = ICMP_UNREACH;
1468 code = ICMP_UNREACH_NEEDFRAG;
1472 * If IPsec is configured for this path,
1473 * override any possibly mtu value set by ip_output.
1475 mtu = ip_ipsec_mtu(m, mtu);
1478 * If the MTU was set before make sure we are below the
1480 * If the MTU wasn't set before use the interface mtu or
1481 * fall back to the next smaller mtu step compared to the
1482 * current packet size.
1486 mtu = min(mtu, ia->ia_ifp->if_mtu);
1489 mtu = ia->ia_ifp->if_mtu;
1491 mtu = ip_next_mtu(ip->ip_len, 0);
1493 V_ipstat.ips_cantfrag++;
1498 * A router should not generate ICMP_SOURCEQUENCH as
1499 * required in RFC1812 Requirements for IP Version 4 Routers.
1500 * Source quench could be a big problem under DoS attacks,
1501 * or if the underlying interface is rate-limited.
1502 * Those who need source quench packets may re-enable them
1503 * via the net.inet.ip.sendsourcequench sysctl.
1505 if (V_ip_sendsourcequench == 0) {
1509 type = ICMP_SOURCEQUENCH;
1514 case EACCES: /* ipfw denied packet */
1518 icmp_error(mcopy, type, code, dest.s_addr, mtu);
1522 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
1525 INIT_VNET_NET(inp->inp_vnet);
1527 if (inp->inp_socket->so_options & (SO_BINTIME | SO_TIMESTAMP)) {
1531 if (inp->inp_socket->so_options & SO_BINTIME) {
1532 *mp = sbcreatecontrol((caddr_t) &bt, sizeof(bt),
1533 SCM_BINTIME, SOL_SOCKET);
1535 mp = &(*mp)->m_next;
1537 if (inp->inp_socket->so_options & SO_TIMESTAMP) {
1540 bintime2timeval(&bt, &tv);
1541 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
1542 SCM_TIMESTAMP, SOL_SOCKET);
1544 mp = &(*mp)->m_next;
1547 if (inp->inp_flags & INP_RECVDSTADDR) {
1548 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst,
1549 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP);
1551 mp = &(*mp)->m_next;
1553 if (inp->inp_flags & INP_RECVTTL) {
1554 *mp = sbcreatecontrol((caddr_t) &ip->ip_ttl,
1555 sizeof(u_char), IP_RECVTTL, IPPROTO_IP);
1557 mp = &(*mp)->m_next;
1561 * Moving these out of udp_input() made them even more broken
1562 * than they already were.
1564 /* options were tossed already */
1565 if (inp->inp_flags & INP_RECVOPTS) {
1566 *mp = sbcreatecontrol((caddr_t) opts_deleted_above,
1567 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP);
1569 mp = &(*mp)->m_next;
1571 /* ip_srcroute doesn't do what we want here, need to fix */
1572 if (inp->inp_flags & INP_RECVRETOPTS) {
1573 *mp = sbcreatecontrol((caddr_t) ip_srcroute(m),
1574 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP);
1576 mp = &(*mp)->m_next;
1579 if (inp->inp_flags & INP_RECVIF) {
1582 struct sockaddr_dl sdl;
1585 struct sockaddr_dl *sdp;
1586 struct sockaddr_dl *sdl2 = &sdlbuf.sdl;
1588 if (((ifp = m->m_pkthdr.rcvif))
1589 && ( ifp->if_index && (ifp->if_index <= V_if_index))) {
1590 sdp = (struct sockaddr_dl *)ifp->if_addr->ifa_addr;
1592 * Change our mind and don't try copy.
1594 if ((sdp->sdl_family != AF_LINK)
1595 || (sdp->sdl_len > sizeof(sdlbuf))) {
1598 bcopy(sdp, sdl2, sdp->sdl_len);
1602 = offsetof(struct sockaddr_dl, sdl_data[0]);
1603 sdl2->sdl_family = AF_LINK;
1604 sdl2->sdl_index = 0;
1605 sdl2->sdl_nlen = sdl2->sdl_alen = sdl2->sdl_slen = 0;
1607 *mp = sbcreatecontrol((caddr_t) sdl2, sdl2->sdl_len,
1608 IP_RECVIF, IPPROTO_IP);
1610 mp = &(*mp)->m_next;
1615 * XXXRW: Multicast routing code in ip_mroute.c is generally MPSAFE, but the
1616 * ip_rsvp and ip_rsvp_on variables need to be interlocked with rsvp_on
1617 * locking. This code remains in ip_input.c as ip_mroute.c is optionally
1621 ip_rsvp_init(struct socket *so)
1623 INIT_VNET_INET(so->so_vnet);
1625 if (so->so_type != SOCK_RAW ||
1626 so->so_proto->pr_protocol != IPPROTO_RSVP)
1629 if (V_ip_rsvpd != NULL)
1634 * This may seem silly, but we need to be sure we don't over-increment
1635 * the RSVP counter, in case something slips up.
1637 if (!V_ip_rsvp_on) {
1648 INIT_VNET_INET(curvnet);
1652 * This may seem silly, but we need to be sure we don't over-decrement
1653 * the RSVP counter, in case something slips up.
1663 rsvp_input(struct mbuf *m, int off) /* XXX must fixup manually */
1665 INIT_VNET_INET(curvnet);
1667 if (rsvp_input_p) { /* call the real one if loaded */
1668 rsvp_input_p(m, off);
1672 /* Can still get packets with rsvp_on = 0 if there is a local member
1673 * of the group to which the RSVP packet is addressed. But in this
1674 * case we want to throw the packet away.
1682 if (V_ip_rsvpd != NULL) {
1686 /* Drop the packet */