2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1986, 1988, 1990, 1993
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31 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
38 #include "opt_ipsec.h"
39 #include "opt_kern_tls.h"
40 #include "opt_mbuf_stress_test.h"
41 #include "opt_ratelimit.h"
42 #include "opt_route.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
51 #include <sys/malloc.h>
55 #include <sys/protosw.h>
56 #include <sys/rmlock.h>
58 #include <sys/socket.h>
59 #include <sys/socketvar.h>
60 #include <sys/sysctl.h>
61 #include <sys/ucred.h>
64 #include <net/if_var.h>
65 #include <net/if_vlan_var.h>
66 #include <net/if_llatbl.h>
67 #include <net/ethernet.h>
68 #include <net/netisr.h>
70 #include <net/route.h>
71 #include <net/route/nhop.h>
72 #include <net/rss_config.h>
75 #include <netinet/in.h>
76 #include <netinet/in_fib.h>
77 #include <netinet/in_kdtrace.h>
78 #include <netinet/in_systm.h>
79 #include <netinet/ip.h>
80 #include <netinet/in_fib.h>
81 #include <netinet/in_pcb.h>
82 #include <netinet/in_rss.h>
83 #include <netinet/in_var.h>
84 #include <netinet/ip_var.h>
85 #include <netinet/ip_options.h>
87 #include <netinet/udp.h>
88 #include <netinet/udp_var.h>
90 #if defined(SCTP) || defined(SCTP_SUPPORT)
91 #include <netinet/sctp.h>
92 #include <netinet/sctp_crc32.h>
95 #include <netipsec/ipsec_support.h>
97 #include <machine/in_cksum.h>
99 #include <security/mac/mac_framework.h>
101 #ifdef MBUF_STRESS_TEST
102 static int mbuf_frag_size = 0;
103 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
104 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
107 static void ip_mloopback(struct ifnet *, const struct mbuf *, int);
109 extern int in_mcast_loop;
110 extern struct protosw inetsw[];
113 ip_output_pfil(struct mbuf **mp, struct ifnet *ifp, int flags,
114 struct inpcb *inp, struct sockaddr_in *dst, int *fibnum, int *error)
116 struct m_tag *fwd_tag = NULL;
120 int pflags = PFIL_OUT;
122 if (flags & IP_FORWARDING)
126 ip = mtod(m, struct ip *);
128 /* Run through list of hooks for output packets. */
129 odst.s_addr = ip->ip_dst.s_addr;
130 switch (pfil_run_hooks(V_inet_pfil_head, mp, ifp, pflags, inp)) {
135 return 1; /* Finished */
140 ip = mtod(m, struct ip *);
142 /* See if destination IP address was changed by packet filter. */
143 if (odst.s_addr != ip->ip_dst.s_addr) {
144 m->m_flags |= M_SKIP_FIREWALL;
145 /* If destination is now ourself drop to ip_input(). */
146 if (in_localip(ip->ip_dst)) {
147 m->m_flags |= M_FASTFWD_OURS;
148 if (m->m_pkthdr.rcvif == NULL)
149 m->m_pkthdr.rcvif = V_loif;
150 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
151 m->m_pkthdr.csum_flags |=
152 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
153 m->m_pkthdr.csum_data = 0xffff;
155 m->m_pkthdr.csum_flags |=
156 CSUM_IP_CHECKED | CSUM_IP_VALID;
157 #if defined(SCTP) || defined(SCTP_SUPPORT)
158 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
159 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
161 *error = netisr_queue(NETISR_IP, m);
162 return 1; /* Finished */
165 bzero(dst, sizeof(*dst));
166 dst->sin_family = AF_INET;
167 dst->sin_len = sizeof(*dst);
168 dst->sin_addr = ip->ip_dst;
170 return -1; /* Reloop */
172 /* See if fib was changed by packet filter. */
173 if ((*fibnum) != M_GETFIB(m)) {
174 m->m_flags |= M_SKIP_FIREWALL;
175 *fibnum = M_GETFIB(m);
176 return -1; /* Reloop for FIB change */
179 /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
180 if (m->m_flags & M_FASTFWD_OURS) {
181 if (m->m_pkthdr.rcvif == NULL)
182 m->m_pkthdr.rcvif = V_loif;
183 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
184 m->m_pkthdr.csum_flags |=
185 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
186 m->m_pkthdr.csum_data = 0xffff;
188 #if defined(SCTP) || defined(SCTP_SUPPORT)
189 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
190 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
192 m->m_pkthdr.csum_flags |=
193 CSUM_IP_CHECKED | CSUM_IP_VALID;
195 *error = netisr_queue(NETISR_IP, m);
196 return 1; /* Finished */
198 /* Or forward to some other address? */
199 if ((m->m_flags & M_IP_NEXTHOP) &&
200 ((fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL)) {
201 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
202 m->m_flags |= M_SKIP_FIREWALL;
203 m->m_flags &= ~M_IP_NEXTHOP;
204 m_tag_delete(m, fwd_tag);
206 return -1; /* Reloop for CHANGE of dst */
213 ip_output_send(struct inpcb *inp, struct ifnet *ifp, struct mbuf *m,
214 const struct sockaddr_in *gw, struct route *ro, bool stamp_tag)
217 struct ktls_session *tls = NULL;
219 struct m_snd_tag *mst;
222 MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
227 * If this is an unencrypted TLS record, save a reference to
228 * the record. This local reference is used to call
229 * ktls_output_eagain after the mbuf has been freed (thus
230 * dropping the mbuf's reference) in if_output.
232 if (m->m_next != NULL && mbuf_has_tls_session(m->m_next)) {
233 tls = ktls_hold(m->m_next->m_epg_tls);
237 * If a TLS session doesn't have a valid tag, it must
238 * have had an earlier ifp mismatch, so drop this
246 * Always stamp tags that include NIC ktls.
252 if (inp != NULL && mst == NULL) {
253 if ((inp->inp_flags2 & INP_RATE_LIMIT_CHANGED) != 0 ||
254 (inp->inp_snd_tag != NULL &&
255 inp->inp_snd_tag->ifp != ifp))
256 in_pcboutput_txrtlmt(inp, ifp, m);
258 if (inp->inp_snd_tag != NULL)
259 mst = inp->inp_snd_tag;
262 if (stamp_tag && mst != NULL) {
263 KASSERT(m->m_pkthdr.rcvif == NULL,
264 ("trying to add a send tag to a forwarded packet"));
265 if (mst->ifp != ifp) {
270 /* stamp send tag on mbuf */
271 m->m_pkthdr.snd_tag = m_snd_tag_ref(mst);
272 m->m_pkthdr.csum_flags |= CSUM_SND_TAG;
275 error = (*ifp->if_output)(ifp, m, (const struct sockaddr *)gw, ro);
278 /* Check for route change invalidating send tags. */
282 error = ktls_output_eagain(inp, tls);
288 in_pcboutput_eagain(inp);
293 /* rte<>ro_flags translation */
295 rt_update_ro_flags(struct route *ro)
297 int nh_flags = ro->ro_nh->nh_flags;
299 ro->ro_flags &= ~ (RT_REJECT|RT_BLACKHOLE|RT_HAS_GW);
301 ro->ro_flags |= (nh_flags & NHF_REJECT) ? RT_REJECT : 0;
302 ro->ro_flags |= (nh_flags & NHF_BLACKHOLE) ? RT_BLACKHOLE : 0;
303 ro->ro_flags |= (nh_flags & NHF_GATEWAY) ? RT_HAS_GW : 0;
307 * IP output. The packet in mbuf chain m contains a skeletal IP
308 * header (with len, off, ttl, proto, tos, src, dst).
309 * The mbuf chain containing the packet will be freed.
310 * The mbuf opt, if present, will not be freed.
311 * If route ro is present and has ro_rt initialized, route lookup would be
312 * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
313 * then result of route lookup is stored in ro->ro_rt.
315 * In the IP forwarding case, the packet will arrive with options already
316 * inserted, so must have a NULL opt pointer.
319 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
320 struct ip_moptions *imo, struct inpcb *inp)
322 struct rm_priotracker in_ifa_tracker;
324 struct ifnet *ifp = NULL; /* keep compiler happy */
326 int hlen = sizeof (struct ip);
330 struct sockaddr_in *dst, sin;
331 const struct sockaddr_in *gw;
332 struct in_ifaddr *ia = NULL;
335 uint16_t ip_len, ip_off;
337 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
338 int no_route_but_check_spd = 0;
345 INP_LOCK_ASSERT(inp);
346 M_SETFIB(m, inp->inp_inc.inc_fibnum);
347 if ((flags & IP_NODEFAULTFLOWID) == 0) {
348 m->m_pkthdr.flowid = inp->inp_flowid;
349 M_HASHTYPE_SET(m, inp->inp_flowtype);
351 if ((inp->inp_flags2 & INP_2PCP_SET) != 0)
352 vlan_pcp = (inp->inp_flags2 & INP_2PCP_MASK) >>
355 m->m_pkthdr.numa_domain = inp->inp_numa_domain;
361 m = ip_insertoptions(m, opt, &len);
363 hlen = len; /* ip->ip_hl is updated above */
365 ip = mtod(m, struct ip *);
366 ip_len = ntohs(ip->ip_len);
367 ip_off = ntohs(ip->ip_off);
369 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
370 ip->ip_v = IPVERSION;
371 ip->ip_hl = hlen >> 2;
374 /* Header already set, fetch hlen from there */
375 hlen = ip->ip_hl << 2;
377 if ((flags & IP_FORWARDING) == 0)
378 IPSTAT_INC(ips_localout);
383 * gw is readonly but can point either to dst OR rt_gateway,
384 * therefore we need restore gw if we're redoing lookup.
386 fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
388 dst = (struct sockaddr_in *)&ro->ro_dst;
391 if (ro == NULL || ro->ro_nh == NULL) {
392 bzero(dst, sizeof(*dst));
393 dst->sin_family = AF_INET;
394 dst->sin_len = sizeof(*dst);
395 dst->sin_addr = ip->ip_dst;
400 * Validate route against routing table additions;
401 * a better/more specific route might have been added.
403 if (inp != NULL && ro != NULL && ro->ro_nh != NULL)
404 NH_VALIDATE(ro, &inp->inp_rt_cookie, fibnum);
406 * If there is a cached route,
407 * check that it is to the same destination
408 * and is still up. If not, free it and try again.
409 * The address family should also be checked in case of sharing the
411 * Also check whether routing cache needs invalidation.
413 if (ro != NULL && ro->ro_nh != NULL &&
414 ((!NH_IS_VALID(ro->ro_nh)) || dst->sin_family != AF_INET ||
415 dst->sin_addr.s_addr != ip->ip_dst.s_addr))
416 RO_INVALIDATE_CACHE(ro);
419 * If routing to interface only, short circuit routing lookup.
420 * The use of an all-ones broadcast address implies this; an
421 * interface is specified by the broadcast address of an interface,
422 * or the destination address of a ptp interface.
424 if (flags & IP_SENDONES) {
425 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst),
426 M_GETFIB(m)))) == NULL &&
427 (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
428 M_GETFIB(m)))) == NULL) {
429 IPSTAT_INC(ips_noroute);
433 ip->ip_dst.s_addr = INADDR_BROADCAST;
434 dst->sin_addr = ip->ip_dst;
439 src = IA_SIN(ia)->sin_addr;
440 } else if (flags & IP_ROUTETOIF) {
441 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
442 M_GETFIB(m)))) == NULL &&
443 (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0,
444 M_GETFIB(m)))) == NULL) {
445 IPSTAT_INC(ips_noroute);
452 isbroadcast = ifp->if_flags & IFF_BROADCAST ?
453 in_ifaddr_broadcast(dst->sin_addr, ia) : 0;
454 src = IA_SIN(ia)->sin_addr;
455 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
456 imo != NULL && imo->imo_multicast_ifp != NULL) {
458 * Bypass the normal routing lookup for multicast
459 * packets if the interface is specified.
461 ifp = imo->imo_multicast_ifp;
463 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
464 isbroadcast = 0; /* fool gcc */
465 /* Interface may have no addresses. */
467 src = IA_SIN(ia)->sin_addr;
469 src.s_addr = INADDR_ANY;
470 } else if (ro != NULL) {
471 if (ro->ro_nh == NULL) {
473 * We want to do any cloning requested by the link
474 * layer, as this is probably required in all cases
475 * for correct operation (as it is for ARP).
478 flowid = m->m_pkthdr.flowid;
479 ro->ro_nh = fib4_lookup(fibnum, dst->sin_addr, 0,
482 if (ro->ro_nh == NULL || (!NH_IS_VALID(ro->ro_nh))) {
483 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
485 * There is no route for this packet, but it is
486 * possible that a matching SPD entry exists.
488 no_route_but_check_spd = 1;
491 IPSTAT_INC(ips_noroute);
492 error = EHOSTUNREACH;
496 ia = ifatoia(ro->ro_nh->nh_ifa);
497 ifp = ro->ro_nh->nh_ifp;
498 counter_u64_add(ro->ro_nh->nh_pksent, 1);
499 rt_update_ro_flags(ro);
500 if (ro->ro_nh->nh_flags & NHF_GATEWAY)
501 gw = &ro->ro_nh->gw4_sa;
502 if (ro->ro_nh->nh_flags & NHF_HOST)
503 isbroadcast = (ro->ro_nh->nh_flags & NHF_BROADCAST);
504 else if (ifp->if_flags & IFF_BROADCAST)
505 isbroadcast = in_ifaddr_broadcast(gw->sin_addr, ia);
508 if (ro->ro_nh->nh_flags & NHF_HOST)
509 mtu = ro->ro_nh->nh_mtu;
512 src = IA_SIN(ia)->sin_addr;
514 struct nhop_object *nh;
516 nh = fib4_lookup(M_GETFIB(m), ip->ip_dst, 0, NHR_NONE,
519 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
521 * There is no route for this packet, but it is
522 * possible that a matching SPD entry exists.
524 no_route_but_check_spd = 1;
527 IPSTAT_INC(ips_noroute);
528 error = EHOSTUNREACH;
534 * We are rewriting here dst to be gw actually, contradicting
535 * comment at the beginning of the function. However, in this
536 * case we are always dealing with on stack dst.
537 * In case if pfil(9) sends us back to beginning of the
538 * function, the dst would be rewritten by ip_output_pfil().
541 if (nh->nh_flags & NHF_GATEWAY)
542 dst->sin_addr = nh->gw4_sa.sin_addr;
543 ia = ifatoia(nh->nh_ifa);
544 src = IA_SIN(ia)->sin_addr;
545 isbroadcast = (((nh->nh_flags & (NHF_HOST | NHF_BROADCAST)) ==
546 (NHF_HOST | NHF_BROADCAST)) ||
547 ((ifp->if_flags & IFF_BROADCAST) &&
548 in_ifaddr_broadcast(dst->sin_addr, ia)));
551 /* Catch a possible divide by zero later. */
552 KASSERT(mtu > 0, ("%s: mtu %d <= 0, ro=%p (nh_flags=0x%08x) ifp=%p",
554 (ro != NULL && ro->ro_nh != NULL) ? ro->ro_nh->nh_flags : 0, ifp));
556 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
557 m->m_flags |= M_MCAST;
559 * IP destination address is multicast. Make sure "gw"
560 * still points to the address in "ro". (It may have been
561 * changed to point to a gateway address, above.)
565 * See if the caller provided any multicast options
568 ip->ip_ttl = imo->imo_multicast_ttl;
569 if (imo->imo_multicast_vif != -1)
572 ip_mcast_src(imo->imo_multicast_vif) :
575 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
577 * Confirm that the outgoing interface supports multicast.
579 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
580 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
581 IPSTAT_INC(ips_noroute);
587 * If source address not specified yet, use address
588 * of outgoing interface.
590 if (ip->ip_src.s_addr == INADDR_ANY)
593 if ((imo == NULL && in_mcast_loop) ||
594 (imo && imo->imo_multicast_loop)) {
596 * Loop back multicast datagram if not expressly
597 * forbidden to do so, even if we are not a member
598 * of the group; ip_input() will filter it later,
599 * thus deferring a hash lookup and mutex acquisition
600 * at the expense of a cheap copy using m_copym().
602 ip_mloopback(ifp, m, hlen);
605 * If we are acting as a multicast router, perform
606 * multicast forwarding as if the packet had just
607 * arrived on the interface to which we are about
608 * to send. The multicast forwarding function
609 * recursively calls this function, using the
610 * IP_FORWARDING flag to prevent infinite recursion.
612 * Multicasts that are looped back by ip_mloopback(),
613 * above, will be forwarded by the ip_input() routine,
616 if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
618 * If rsvp daemon is not running, do not
619 * set ip_moptions. This ensures that the packet
620 * is multicast and not just sent down one link
621 * as prescribed by rsvpd.
626 ip_mforward(ip, ifp, m, imo) != 0) {
634 * Multicasts with a time-to-live of zero may be looped-
635 * back, above, but must not be transmitted on a network.
636 * Also, multicasts addressed to the loopback interface
637 * are not sent -- the above call to ip_mloopback() will
638 * loop back a copy. ip_input() will drop the copy if
639 * this host does not belong to the destination group on
640 * the loopback interface.
642 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
651 * If the source address is not specified yet, use the address
652 * of the outoing interface.
654 if (ip->ip_src.s_addr == INADDR_ANY)
658 * Look for broadcast address and
659 * verify user is allowed to send
663 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
664 error = EADDRNOTAVAIL;
667 if ((flags & IP_ALLOWBROADCAST) == 0) {
671 /* don't allow broadcast messages to be fragmented */
676 m->m_flags |= M_BCAST;
678 m->m_flags &= ~M_BCAST;
682 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
683 if (IPSEC_ENABLED(ipv4)) {
684 if ((error = IPSEC_OUTPUT(ipv4, m, inp)) != 0) {
685 if (error == EINPROGRESS)
691 * Check if there was a route for this packet; return error if not.
693 if (no_route_but_check_spd) {
694 IPSTAT_INC(ips_noroute);
695 error = EHOSTUNREACH;
698 /* Update variables that are affected by ipsec4_output(). */
699 ip = mtod(m, struct ip *);
700 hlen = ip->ip_hl << 2;
703 /* Jump over all PFIL processing if hooks are not active. */
704 if (PFIL_HOOKED_OUT(V_inet_pfil_head)) {
705 switch (ip_output_pfil(&m, ifp, flags, inp, dst, &fibnum,
707 case 1: /* Finished */
710 case 0: /* Continue normally */
711 ip = mtod(m, struct ip *);
714 case -1: /* Need to try again */
715 /* Reset everything for a new round */
718 ro->ro_prepend = NULL;
721 ip = mtod(m, struct ip *);
727 EVL_APPLY_PRI(m, vlan_pcp);
729 /* IN_LOOPBACK must not appear on the wire - RFC1122. */
730 if (IN_LOOPBACK(ntohl(ip->ip_dst.s_addr)) ||
731 IN_LOOPBACK(ntohl(ip->ip_src.s_addr))) {
732 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
733 IPSTAT_INC(ips_badaddr);
734 error = EADDRNOTAVAIL;
739 m->m_pkthdr.csum_flags |= CSUM_IP;
740 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
741 m = mb_unmapped_to_ext(m);
743 IPSTAT_INC(ips_odropped);
748 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
749 } else if ((ifp->if_capenable & IFCAP_NOMAP) == 0) {
750 m = mb_unmapped_to_ext(m);
752 IPSTAT_INC(ips_odropped);
757 #if defined(SCTP) || defined(SCTP_SUPPORT)
758 if (m->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
759 m = mb_unmapped_to_ext(m);
761 IPSTAT_INC(ips_odropped);
765 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
766 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
771 * If small enough for interface, or the interface will take
772 * care of the fragmentation for us, we can just send directly.
773 * Note that if_vxlan could have requested TSO even though the outer
774 * frame is UDP. It is correct to not fragment such datagrams and
775 * instead just pass them on to the driver.
778 (m->m_pkthdr.csum_flags & ifp->if_hwassist &
779 (CSUM_TSO | CSUM_INNER_TSO)) != 0) {
781 if (m->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
782 ip->ip_sum = in_cksum(m, hlen);
783 m->m_pkthdr.csum_flags &= ~CSUM_IP;
787 * Record statistics for this interface address.
788 * With CSUM_TSO the byte/packet count will be slightly
789 * incorrect because we count the IP+TCP headers only
790 * once instead of for every generated packet.
792 if (!(flags & IP_FORWARDING) && ia) {
793 if (m->m_pkthdr.csum_flags &
794 (CSUM_TSO | CSUM_INNER_TSO))
795 counter_u64_add(ia->ia_ifa.ifa_opackets,
796 m->m_pkthdr.len / m->m_pkthdr.tso_segsz);
798 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
800 counter_u64_add(ia->ia_ifa.ifa_obytes, m->m_pkthdr.len);
802 #ifdef MBUF_STRESS_TEST
803 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
804 m = m_fragment(m, M_NOWAIT, mbuf_frag_size);
807 * Reset layer specific mbuf flags
808 * to avoid confusing lower layers.
811 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
812 error = ip_output_send(inp, ifp, m, gw, ro,
813 (flags & IP_NO_SND_TAG_RL) ? false : true);
817 /* Balk when DF bit is set or the interface didn't support TSO. */
818 if ((ip_off & IP_DF) ||
819 (m->m_pkthdr.csum_flags & (CSUM_TSO | CSUM_INNER_TSO))) {
821 IPSTAT_INC(ips_cantfrag);
826 * Too large for interface; fragment if possible. If successful,
827 * on return, m will point to a list of packets to be sent.
829 error = ip_fragment(ip, &m, mtu, ifp->if_hwassist);
836 /* Record statistics for this interface address. */
838 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
839 counter_u64_add(ia->ia_ifa.ifa_obytes,
843 * Reset layer specific mbuf flags
844 * to avoid confusing upper layers.
848 IP_PROBE(send, NULL, NULL, mtod(m, struct ip *), ifp,
849 mtod(m, struct ip *), NULL);
850 error = ip_output_send(inp, ifp, m, gw, ro, true);
856 IPSTAT_INC(ips_fragmented);
866 * Create a chain of fragments which fit the given mtu. m_frag points to the
867 * mbuf to be fragmented; on return it points to the chain with the fragments.
868 * Return 0 if no error. If error, m_frag may contain a partially built
869 * chain of fragments that should be freed by the caller.
871 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
874 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
875 u_long if_hwassist_flags)
878 int hlen = ip->ip_hl << 2;
879 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
881 struct mbuf *m0 = *m_frag; /* the original packet */
885 uint16_t ip_len, ip_off;
887 ip_len = ntohs(ip->ip_len);
888 ip_off = ntohs(ip->ip_off);
890 if (ip_off & IP_DF) { /* Fragmentation not allowed */
891 IPSTAT_INC(ips_cantfrag);
896 * Must be able to put at least 8 bytes per fragment.
902 * If the interface will not calculate checksums on
903 * fragmented packets, then do it here.
905 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
906 m0 = mb_unmapped_to_ext(m0);
909 IPSTAT_INC(ips_odropped);
912 in_delayed_cksum(m0);
913 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
915 #if defined(SCTP) || defined(SCTP_SUPPORT)
916 if (m0->m_pkthdr.csum_flags & CSUM_SCTP) {
917 m0 = mb_unmapped_to_ext(m0);
920 IPSTAT_INC(ips_odropped);
923 sctp_delayed_cksum(m0, hlen);
924 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
927 if (len > PAGE_SIZE) {
929 * Fragment large datagrams such that each segment
930 * contains a multiple of PAGE_SIZE amount of data,
931 * plus headers. This enables a receiver to perform
932 * page-flipping zero-copy optimizations.
934 * XXX When does this help given that sender and receiver
935 * could have different page sizes, and also mtu could
936 * be less than the receiver's page size ?
940 off = MIN(mtu, m0->m_pkthdr.len);
943 * firstlen (off - hlen) must be aligned on an
947 goto smart_frag_failure;
948 off = ((off - hlen) & ~7) + hlen;
949 newlen = (~PAGE_MASK) & mtu;
950 if ((newlen + sizeof (struct ip)) > mtu) {
951 /* we failed, go back the default */
962 firstlen = off - hlen;
963 mnext = &m0->m_nextpkt; /* pointer to next packet */
966 * Loop through length of segment after first fragment,
967 * make new header and copy data of each part and link onto chain.
968 * Here, m0 is the original packet, m is the fragment being created.
969 * The fragments are linked off the m_nextpkt of the original
970 * packet, which after processing serves as the first fragment.
972 for (nfrags = 1; off < ip_len; off += len, nfrags++) {
973 struct ip *mhip; /* ip header on the fragment */
975 int mhlen = sizeof (struct ip);
977 m = m_gethdr(M_NOWAIT, MT_DATA);
980 IPSTAT_INC(ips_odropped);
984 * Make sure the complete packet header gets copied
985 * from the originating mbuf to the newly created
986 * mbuf. This also ensures that existing firewall
987 * classification(s), VLAN tags and so on get copied
988 * to the resulting fragmented packet(s):
990 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
993 IPSTAT_INC(ips_odropped);
997 * In the first mbuf, leave room for the link header, then
998 * copy the original IP header including options. The payload
999 * goes into an additional mbuf chain returned by m_copym().
1001 m->m_data += max_linkhdr;
1002 mhip = mtod(m, struct ip *);
1004 if (hlen > sizeof (struct ip)) {
1005 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
1006 mhip->ip_v = IPVERSION;
1007 mhip->ip_hl = mhlen >> 2;
1010 /* XXX do we need to add ip_off below ? */
1011 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
1012 if (off + len >= ip_len)
1015 mhip->ip_off |= IP_MF;
1016 mhip->ip_len = htons((u_short)(len + mhlen));
1017 m->m_next = m_copym(m0, off, len, M_NOWAIT);
1018 if (m->m_next == NULL) { /* copy failed */
1020 error = ENOBUFS; /* ??? */
1021 IPSTAT_INC(ips_odropped);
1024 m->m_pkthdr.len = mhlen + len;
1026 mac_netinet_fragment(m0, m);
1028 mhip->ip_off = htons(mhip->ip_off);
1030 if (m->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
1031 mhip->ip_sum = in_cksum(m, mhlen);
1032 m->m_pkthdr.csum_flags &= ~CSUM_IP;
1035 mnext = &m->m_nextpkt;
1037 IPSTAT_ADD(ips_ofragments, nfrags);
1040 * Update first fragment by trimming what's been copied out
1041 * and updating header.
1043 m_adj(m0, hlen + firstlen - ip_len);
1044 m0->m_pkthdr.len = hlen + firstlen;
1045 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1046 ip->ip_off = htons(ip_off | IP_MF);
1048 if (m0->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
1049 ip->ip_sum = in_cksum(m0, hlen);
1050 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
1059 in_delayed_cksum(struct mbuf *m)
1063 uint16_t cklen, csum, offset;
1065 ip = mtod(m, struct ip *);
1066 offset = ip->ip_hl << 2 ;
1068 if (m->m_pkthdr.csum_flags & CSUM_UDP) {
1069 /* if udp header is not in the first mbuf copy udplen */
1070 if (offset + sizeof(struct udphdr) > m->m_len) {
1071 m_copydata(m, offset + offsetof(struct udphdr,
1072 uh_ulen), sizeof(cklen), (caddr_t)&cklen);
1073 cklen = ntohs(cklen);
1075 uh = (struct udphdr *)mtodo(m, offset);
1076 cklen = ntohs(uh->uh_ulen);
1078 csum = in_cksum_skip(m, cklen + offset, offset);
1082 cklen = ntohs(ip->ip_len);
1083 csum = in_cksum_skip(m, cklen, offset);
1085 offset += m->m_pkthdr.csum_data; /* checksum offset */
1087 if (offset + sizeof(csum) > m->m_len)
1088 m_copyback(m, offset, sizeof(csum), (caddr_t)&csum);
1090 *(u_short *)mtodo(m, offset) = csum;
1094 * IP socket option processing.
1097 ip_ctloutput(struct socket *so, struct sockopt *sopt)
1099 struct inpcb *inp = sotoinpcb(so);
1102 uint32_t rss_bucket;
1107 if (sopt->sopt_level != IPPROTO_IP) {
1110 if (sopt->sopt_level == SOL_SOCKET &&
1111 sopt->sopt_dir == SOPT_SET) {
1112 switch (sopt->sopt_name) {
1115 if ((so->so_options & SO_REUSEADDR) != 0)
1116 inp->inp_flags2 |= INP_REUSEADDR;
1118 inp->inp_flags2 &= ~INP_REUSEADDR;
1124 if ((so->so_options & SO_REUSEPORT) != 0)
1125 inp->inp_flags2 |= INP_REUSEPORT;
1127 inp->inp_flags2 &= ~INP_REUSEPORT;
1131 case SO_REUSEPORT_LB:
1133 if ((so->so_options & SO_REUSEPORT_LB) != 0)
1134 inp->inp_flags2 |= INP_REUSEPORT_LB;
1136 inp->inp_flags2 &= ~INP_REUSEPORT_LB;
1142 inp->inp_inc.inc_fibnum = so->so_fibnum;
1146 case SO_MAX_PACING_RATE:
1149 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1163 switch (sopt->sopt_dir) {
1165 switch (sopt->sopt_name) {
1172 if (sopt->sopt_valsize > MLEN) {
1176 m = m_get(sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
1181 m->m_len = sopt->sopt_valsize;
1182 error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1189 error = ip_pcbopts(inp, sopt->sopt_name, m);
1195 if (sopt->sopt_td != NULL) {
1196 error = priv_check(sopt->sopt_td,
1197 PRIV_NETINET_BINDANY);
1204 case IP_RSS_LISTEN_BUCKET:
1210 case IP_RECVRETOPTS:
1211 case IP_ORIGDSTADDR:
1212 case IP_RECVDSTADDR:
1220 case IP_RECVRSSBUCKETID:
1223 error = sooptcopyin(sopt, &optval, sizeof optval,
1228 switch (sopt->sopt_name) {
1230 inp->inp_ip_tos = optval;
1234 inp->inp_ip_ttl = optval;
1238 if (optval >= 0 && optval <= MAXTTL)
1239 inp->inp_ip_minttl = optval;
1244 #define OPTSET(bit) do { \
1247 inp->inp_flags |= bit; \
1249 inp->inp_flags &= ~bit; \
1253 #define OPTSET2(bit, val) do { \
1256 inp->inp_flags2 |= bit; \
1258 inp->inp_flags2 &= ~bit; \
1263 OPTSET(INP_RECVOPTS);
1266 case IP_RECVRETOPTS:
1267 OPTSET(INP_RECVRETOPTS);
1270 case IP_RECVDSTADDR:
1271 OPTSET(INP_RECVDSTADDR);
1274 case IP_ORIGDSTADDR:
1275 OPTSET2(INP_ORIGDSTADDR, optval);
1279 OPTSET(INP_RECVTTL);
1287 OPTSET(INP_ONESBCAST);
1290 OPTSET(INP_DONTFRAG);
1293 OPTSET(INP_BINDANY);
1296 OPTSET(INP_RECVTOS);
1299 OPTSET2(INP_BINDMULTI, optval);
1302 OPTSET2(INP_RECVFLOWID, optval);
1305 case IP_RSS_LISTEN_BUCKET:
1306 if ((optval >= 0) &&
1307 (optval < rss_getnumbuckets())) {
1308 inp->inp_rss_listen_bucket = optval;
1309 OPTSET2(INP_RSS_BUCKET_SET, 1);
1314 case IP_RECVRSSBUCKETID:
1315 OPTSET2(INP_RECVRSSBUCKETID, optval);
1319 if ((optval >= -1) && (optval <=
1320 (INP_2PCP_MASK >> INP_2PCP_SHIFT))) {
1334 optval << INP_2PCP_SHIFT;
1346 * Multicast socket options are processed by the in_mcast
1349 case IP_MULTICAST_IF:
1350 case IP_MULTICAST_VIF:
1351 case IP_MULTICAST_TTL:
1352 case IP_MULTICAST_LOOP:
1353 case IP_ADD_MEMBERSHIP:
1354 case IP_DROP_MEMBERSHIP:
1355 case IP_ADD_SOURCE_MEMBERSHIP:
1356 case IP_DROP_SOURCE_MEMBERSHIP:
1357 case IP_BLOCK_SOURCE:
1358 case IP_UNBLOCK_SOURCE:
1360 case MCAST_JOIN_GROUP:
1361 case MCAST_LEAVE_GROUP:
1362 case MCAST_JOIN_SOURCE_GROUP:
1363 case MCAST_LEAVE_SOURCE_GROUP:
1364 case MCAST_BLOCK_SOURCE:
1365 case MCAST_UNBLOCK_SOURCE:
1366 error = inp_setmoptions(inp, sopt);
1370 error = sooptcopyin(sopt, &optval, sizeof optval,
1377 case IP_PORTRANGE_DEFAULT:
1378 inp->inp_flags &= ~(INP_LOWPORT);
1379 inp->inp_flags &= ~(INP_HIGHPORT);
1382 case IP_PORTRANGE_HIGH:
1383 inp->inp_flags &= ~(INP_LOWPORT);
1384 inp->inp_flags |= INP_HIGHPORT;
1387 case IP_PORTRANGE_LOW:
1388 inp->inp_flags &= ~(INP_HIGHPORT);
1389 inp->inp_flags |= INP_LOWPORT;
1399 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1400 case IP_IPSEC_POLICY:
1401 if (IPSEC_ENABLED(ipv4)) {
1402 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1409 error = ENOPROTOOPT;
1415 switch (sopt->sopt_name) {
1419 if (inp->inp_options) {
1420 struct mbuf *options;
1422 options = m_copym(inp->inp_options, 0,
1423 M_COPYALL, M_NOWAIT);
1425 if (options != NULL) {
1426 error = sooptcopyout(sopt,
1427 mtod(options, char *),
1434 sopt->sopt_valsize = 0;
1442 case IP_RECVRETOPTS:
1443 case IP_ORIGDSTADDR:
1444 case IP_RECVDSTADDR:
1457 case IP_RSSBUCKETID:
1458 case IP_RECVRSSBUCKETID:
1461 switch (sopt->sopt_name) {
1463 optval = inp->inp_ip_tos;
1467 optval = inp->inp_ip_ttl;
1471 optval = inp->inp_ip_minttl;
1474 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1475 #define OPTBIT2(bit) (inp->inp_flags2 & bit ? 1 : 0)
1478 optval = OPTBIT(INP_RECVOPTS);
1481 case IP_RECVRETOPTS:
1482 optval = OPTBIT(INP_RECVRETOPTS);
1485 case IP_RECVDSTADDR:
1486 optval = OPTBIT(INP_RECVDSTADDR);
1489 case IP_ORIGDSTADDR:
1490 optval = OPTBIT2(INP_ORIGDSTADDR);
1494 optval = OPTBIT(INP_RECVTTL);
1498 optval = OPTBIT(INP_RECVIF);
1502 if (inp->inp_flags & INP_HIGHPORT)
1503 optval = IP_PORTRANGE_HIGH;
1504 else if (inp->inp_flags & INP_LOWPORT)
1505 optval = IP_PORTRANGE_LOW;
1511 optval = OPTBIT(INP_ONESBCAST);
1514 optval = OPTBIT(INP_DONTFRAG);
1517 optval = OPTBIT(INP_BINDANY);
1520 optval = OPTBIT(INP_RECVTOS);
1523 optval = inp->inp_flowid;
1526 optval = inp->inp_flowtype;
1529 optval = OPTBIT2(INP_RECVFLOWID);
1532 case IP_RSSBUCKETID:
1533 retval = rss_hash2bucket(inp->inp_flowid,
1537 optval = rss_bucket;
1541 case IP_RECVRSSBUCKETID:
1542 optval = OPTBIT2(INP_RECVRSSBUCKETID);
1546 optval = OPTBIT2(INP_BINDMULTI);
1549 if (OPTBIT2(INP_2PCP_SET)) {
1550 optval = (inp->inp_flags2 &
1551 INP_2PCP_MASK) >> INP_2PCP_SHIFT;
1557 error = sooptcopyout(sopt, &optval, sizeof optval);
1561 * Multicast socket options are processed by the in_mcast
1564 case IP_MULTICAST_IF:
1565 case IP_MULTICAST_VIF:
1566 case IP_MULTICAST_TTL:
1567 case IP_MULTICAST_LOOP:
1569 error = inp_getmoptions(inp, sopt);
1572 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1573 case IP_IPSEC_POLICY:
1574 if (IPSEC_ENABLED(ipv4)) {
1575 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1582 error = ENOPROTOOPT;
1591 * Routine called from ip_output() to loop back a copy of an IP multicast
1592 * packet to the input queue of a specified interface. Note that this
1593 * calls the output routine of the loopback "driver", but with an interface
1594 * pointer that might NOT be a loopback interface -- evil, but easier than
1595 * replicating that code here.
1598 ip_mloopback(struct ifnet *ifp, const struct mbuf *m, int hlen)
1604 * Make a deep copy of the packet because we're going to
1605 * modify the pack in order to generate checksums.
1607 copym = m_dup(m, M_NOWAIT);
1608 if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen))
1609 copym = m_pullup(copym, hlen);
1610 if (copym != NULL) {
1611 /* If needed, compute the checksum and mark it as valid. */
1612 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1613 in_delayed_cksum(copym);
1614 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1615 copym->m_pkthdr.csum_flags |=
1616 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1617 copym->m_pkthdr.csum_data = 0xffff;
1620 * We don't bother to fragment if the IP length is greater
1621 * than the interface's MTU. Can this possibly matter?
1623 ip = mtod(copym, struct ip *);
1625 ip->ip_sum = in_cksum(copym, hlen);
1626 if_simloop(ifp, copym, AF_INET, 0);