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_ratelimit.h"
39 #include "opt_ipsec.h"
40 #include "opt_mbuf_stress_test.h"
41 #include "opt_mpath.h"
42 #include "opt_route.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
50 #include <sys/malloc.h>
54 #include <sys/protosw.h>
55 #include <sys/rmlock.h>
57 #include <sys/socket.h>
58 #include <sys/socketvar.h>
59 #include <sys/sysctl.h>
60 #include <sys/ucred.h>
63 #include <net/if_var.h>
64 #include <net/if_llatbl.h>
65 #include <net/netisr.h>
67 #include <net/route.h>
69 #include <net/radix_mpath.h>
71 #include <net/rss_config.h>
74 #include <netinet/in.h>
75 #include <netinet/in_kdtrace.h>
76 #include <netinet/in_systm.h>
77 #include <netinet/ip.h>
78 #include <netinet/in_pcb.h>
79 #include <netinet/in_rss.h>
80 #include <netinet/in_var.h>
81 #include <netinet/ip_var.h>
82 #include <netinet/ip_options.h>
84 #include <netinet/sctp.h>
85 #include <netinet/sctp_crc32.h>
88 #include <netipsec/ipsec_support.h>
90 #include <machine/in_cksum.h>
92 #include <security/mac/mac_framework.h>
94 #ifdef MBUF_STRESS_TEST
95 static int mbuf_frag_size = 0;
96 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
97 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
100 static void ip_mloopback(struct ifnet *, const struct mbuf *, int);
103 extern int in_mcast_loop;
104 extern struct protosw inetsw[];
107 ip_output_pfil(struct mbuf **mp, struct ifnet *ifp, struct inpcb *inp,
108 struct sockaddr_in *dst, int *fibnum, int *error)
110 struct m_tag *fwd_tag = NULL;
116 ip = mtod(m, struct ip *);
118 /* Run through list of hooks for output packets. */
119 odst.s_addr = ip->ip_dst.s_addr;
120 *error = pfil_run_hooks(&V_inet_pfil_hook, mp, ifp, PFIL_OUT, inp);
122 if ((*error) != 0 || m == NULL)
123 return 1; /* Finished */
125 ip = mtod(m, struct ip *);
127 /* See if destination IP address was changed by packet filter. */
128 if (odst.s_addr != ip->ip_dst.s_addr) {
129 m->m_flags |= M_SKIP_FIREWALL;
130 /* If destination is now ourself drop to ip_input(). */
131 if (in_localip(ip->ip_dst)) {
132 m->m_flags |= M_FASTFWD_OURS;
133 if (m->m_pkthdr.rcvif == NULL)
134 m->m_pkthdr.rcvif = V_loif;
135 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
136 m->m_pkthdr.csum_flags |=
137 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
138 m->m_pkthdr.csum_data = 0xffff;
140 m->m_pkthdr.csum_flags |=
141 CSUM_IP_CHECKED | CSUM_IP_VALID;
143 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
144 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
146 *error = netisr_queue(NETISR_IP, m);
147 return 1; /* Finished */
150 bzero(dst, sizeof(*dst));
151 dst->sin_family = AF_INET;
152 dst->sin_len = sizeof(*dst);
153 dst->sin_addr = ip->ip_dst;
155 return -1; /* Reloop */
157 /* See if fib was changed by packet filter. */
158 if ((*fibnum) != M_GETFIB(m)) {
159 m->m_flags |= M_SKIP_FIREWALL;
160 *fibnum = M_GETFIB(m);
161 return -1; /* Reloop for FIB change */
164 /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
165 if (m->m_flags & M_FASTFWD_OURS) {
166 if (m->m_pkthdr.rcvif == NULL)
167 m->m_pkthdr.rcvif = V_loif;
168 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
169 m->m_pkthdr.csum_flags |=
170 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
171 m->m_pkthdr.csum_data = 0xffff;
174 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
175 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
177 m->m_pkthdr.csum_flags |=
178 CSUM_IP_CHECKED | CSUM_IP_VALID;
180 *error = netisr_queue(NETISR_IP, m);
181 return 1; /* Finished */
183 /* Or forward to some other address? */
184 if ((m->m_flags & M_IP_NEXTHOP) &&
185 ((fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL)) {
186 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
187 m->m_flags |= M_SKIP_FIREWALL;
188 m->m_flags &= ~M_IP_NEXTHOP;
189 m_tag_delete(m, fwd_tag);
191 return -1; /* Reloop for CHANGE of dst */
198 * IP output. The packet in mbuf chain m contains a skeletal IP
199 * header (with len, off, ttl, proto, tos, src, dst).
200 * The mbuf chain containing the packet will be freed.
201 * The mbuf opt, if present, will not be freed.
202 * If route ro is present and has ro_rt initialized, route lookup would be
203 * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
204 * then result of route lookup is stored in ro->ro_rt.
206 * In the IP forwarding case, the packet will arrive with options already
207 * inserted, so must have a NULL opt pointer.
210 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
211 struct ip_moptions *imo, struct inpcb *inp)
213 struct rm_priotracker in_ifa_tracker;
215 struct ifnet *ifp = NULL; /* keep compiler happy */
217 int hlen = sizeof (struct ip);
220 struct sockaddr_in *dst;
221 const struct sockaddr_in *gw;
222 struct in_ifaddr *ia;
224 uint16_t ip_len, ip_off;
225 struct route iproute;
226 struct rtentry *rte; /* cache for ro->ro_rt */
229 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
230 int no_route_but_check_spd = 0;
235 INP_LOCK_ASSERT(inp);
236 M_SETFIB(m, inp->inp_inc.inc_fibnum);
237 if ((flags & IP_NODEFAULTFLOWID) == 0) {
238 m->m_pkthdr.flowid = inp->inp_flowid;
239 M_HASHTYPE_SET(m, inp->inp_flowtype);
245 bzero(ro, sizeof (*ro));
250 m = ip_insertoptions(m, opt, &len);
252 hlen = len; /* ip->ip_hl is updated above */
254 ip = mtod(m, struct ip *);
255 ip_len = ntohs(ip->ip_len);
256 ip_off = ntohs(ip->ip_off);
258 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
259 ip->ip_v = IPVERSION;
260 ip->ip_hl = hlen >> 2;
262 IPSTAT_INC(ips_localout);
264 /* Header already set, fetch hlen from there */
265 hlen = ip->ip_hl << 2;
271 * dst can be rewritten but always points to &ro->ro_dst.
272 * gw is readonly but can point either to dst OR rt_gateway,
273 * therefore we need restore gw if we're redoing lookup.
275 gw = dst = (struct sockaddr_in *)&ro->ro_dst;
276 fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
279 bzero(dst, sizeof(*dst));
280 dst->sin_family = AF_INET;
281 dst->sin_len = sizeof(*dst);
282 dst->sin_addr = ip->ip_dst;
286 * Validate route against routing table additions;
287 * a better/more specific route might have been added.
290 RT_VALIDATE(ro, &inp->inp_rt_cookie, fibnum);
292 * If there is a cached route,
293 * check that it is to the same destination
294 * and is still up. If not, free it and try again.
295 * The address family should also be checked in case of sharing the
297 * Also check whether routing cache needs invalidation.
300 if (rte && ((rte->rt_flags & RTF_UP) == 0 ||
301 rte->rt_ifp == NULL ||
302 !RT_LINK_IS_UP(rte->rt_ifp) ||
303 dst->sin_family != AF_INET ||
304 dst->sin_addr.s_addr != ip->ip_dst.s_addr)) {
305 RO_INVALIDATE_CACHE(ro);
311 * If routing to interface only, short circuit routing lookup.
312 * The use of an all-ones broadcast address implies this; an
313 * interface is specified by the broadcast address of an interface,
314 * or the destination address of a ptp interface.
316 if (flags & IP_SENDONES) {
317 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst),
318 M_GETFIB(m)))) == NULL &&
319 (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
320 M_GETFIB(m)))) == NULL) {
321 IPSTAT_INC(ips_noroute);
326 ip->ip_dst.s_addr = INADDR_BROADCAST;
327 dst->sin_addr = ip->ip_dst;
331 } else if (flags & IP_ROUTETOIF) {
332 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
333 M_GETFIB(m)))) == NULL &&
334 (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0,
335 M_GETFIB(m)))) == NULL) {
336 IPSTAT_INC(ips_noroute);
343 isbroadcast = ifp->if_flags & IFF_BROADCAST ?
344 in_ifaddr_broadcast(dst->sin_addr, ia) : 0;
345 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
346 imo != NULL && imo->imo_multicast_ifp != NULL) {
348 * Bypass the normal routing lookup for multicast
349 * packets if the interface is specified.
351 ifp = imo->imo_multicast_ifp;
352 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
355 isbroadcast = 0; /* fool gcc */
358 * We want to do any cloning requested by the link layer,
359 * as this is probably required in all cases for correct
360 * operation (as it is for ARP).
364 rtalloc_mpath_fib(ro,
365 ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr),
368 in_rtalloc_ign(ro, 0, fibnum);
373 (rte->rt_flags & RTF_UP) == 0 ||
374 rte->rt_ifp == NULL ||
375 !RT_LINK_IS_UP(rte->rt_ifp)) {
376 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
378 * There is no route for this packet, but it is
379 * possible that a matching SPD entry exists.
381 no_route_but_check_spd = 1;
382 mtu = 0; /* Silence GCC warning. */
385 IPSTAT_INC(ips_noroute);
386 error = EHOSTUNREACH;
389 ia = ifatoia(rte->rt_ifa);
391 counter_u64_add(rte->rt_pksent, 1);
392 rt_update_ro_flags(ro);
393 if (rte->rt_flags & RTF_GATEWAY)
394 gw = (struct sockaddr_in *)rte->rt_gateway;
395 if (rte->rt_flags & RTF_HOST)
396 isbroadcast = (rte->rt_flags & RTF_BROADCAST);
397 else if (ifp->if_flags & IFF_BROADCAST)
398 isbroadcast = in_ifaddr_broadcast(gw->sin_addr, ia);
404 * Calculate MTU. If we have a route that is up, use that,
405 * otherwise use the interface's MTU.
407 if (rte != NULL && (rte->rt_flags & (RTF_UP|RTF_HOST)))
411 /* Catch a possible divide by zero later. */
412 KASSERT(mtu > 0, ("%s: mtu %d <= 0, rte=%p (rt_flags=0x%08x) ifp=%p",
413 __func__, mtu, rte, (rte != NULL) ? rte->rt_flags : 0, ifp));
415 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
416 m->m_flags |= M_MCAST;
418 * IP destination address is multicast. Make sure "gw"
419 * still points to the address in "ro". (It may have been
420 * changed to point to a gateway address, above.)
424 * See if the caller provided any multicast options
427 ip->ip_ttl = imo->imo_multicast_ttl;
428 if (imo->imo_multicast_vif != -1)
431 ip_mcast_src(imo->imo_multicast_vif) :
434 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
436 * Confirm that the outgoing interface supports multicast.
438 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
439 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
440 IPSTAT_INC(ips_noroute);
446 * If source address not specified yet, use address
447 * of outgoing interface.
449 if (ip->ip_src.s_addr == INADDR_ANY) {
450 /* Interface may have no addresses. */
452 ip->ip_src = IA_SIN(ia)->sin_addr;
455 if ((imo == NULL && in_mcast_loop) ||
456 (imo && imo->imo_multicast_loop)) {
458 * Loop back multicast datagram if not expressly
459 * forbidden to do so, even if we are not a member
460 * of the group; ip_input() will filter it later,
461 * thus deferring a hash lookup and mutex acquisition
462 * at the expense of a cheap copy using m_copym().
464 ip_mloopback(ifp, m, hlen);
467 * If we are acting as a multicast router, perform
468 * multicast forwarding as if the packet had just
469 * arrived on the interface to which we are about
470 * to send. The multicast forwarding function
471 * recursively calls this function, using the
472 * IP_FORWARDING flag to prevent infinite recursion.
474 * Multicasts that are looped back by ip_mloopback(),
475 * above, will be forwarded by the ip_input() routine,
478 if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
480 * If rsvp daemon is not running, do not
481 * set ip_moptions. This ensures that the packet
482 * is multicast and not just sent down one link
483 * as prescribed by rsvpd.
488 ip_mforward(ip, ifp, m, imo) != 0) {
496 * Multicasts with a time-to-live of zero may be looped-
497 * back, above, but must not be transmitted on a network.
498 * Also, multicasts addressed to the loopback interface
499 * are not sent -- the above call to ip_mloopback() will
500 * loop back a copy. ip_input() will drop the copy if
501 * this host does not belong to the destination group on
502 * the loopback interface.
504 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
513 * If the source address is not specified yet, use the address
514 * of the outoing interface.
516 if (ip->ip_src.s_addr == INADDR_ANY) {
517 /* Interface may have no addresses. */
519 ip->ip_src = IA_SIN(ia)->sin_addr;
524 * Look for broadcast address and
525 * verify user is allowed to send
529 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
530 error = EADDRNOTAVAIL;
533 if ((flags & IP_ALLOWBROADCAST) == 0) {
537 /* don't allow broadcast messages to be fragmented */
542 m->m_flags |= M_BCAST;
544 m->m_flags &= ~M_BCAST;
548 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
549 if (IPSEC_ENABLED(ipv4)) {
550 if ((error = IPSEC_OUTPUT(ipv4, m, inp)) != 0) {
551 if (error == EINPROGRESS)
557 * Check if there was a route for this packet; return error if not.
559 if (no_route_but_check_spd) {
560 IPSTAT_INC(ips_noroute);
561 error = EHOSTUNREACH;
564 /* Update variables that are affected by ipsec4_output(). */
565 ip = mtod(m, struct ip *);
566 hlen = ip->ip_hl << 2;
569 /* Jump over all PFIL processing if hooks are not active. */
570 if (PFIL_HOOKED(&V_inet_pfil_hook)) {
571 switch (ip_output_pfil(&m, ifp, inp, dst, &fibnum, &error)) {
572 case 1: /* Finished */
575 case 0: /* Continue normally */
576 ip = mtod(m, struct ip *);
579 case -1: /* Need to try again */
580 /* Reset everything for a new round */
583 ifa_free(&ia->ia_ifa);
584 ro->ro_prepend = NULL;
587 ip = mtod(m, struct ip *);
593 /* 127/8 must not appear on wire - RFC1122. */
594 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
595 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
596 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
597 IPSTAT_INC(ips_badaddr);
598 error = EADDRNOTAVAIL;
603 m->m_pkthdr.csum_flags |= CSUM_IP;
604 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
606 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
609 if (m->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
610 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
611 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
616 * If small enough for interface, or the interface will take
617 * care of the fragmentation for us, we can just send directly.
620 (m->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
622 if (m->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
623 ip->ip_sum = in_cksum(m, hlen);
624 m->m_pkthdr.csum_flags &= ~CSUM_IP;
628 * Record statistics for this interface address.
629 * With CSUM_TSO the byte/packet count will be slightly
630 * incorrect because we count the IP+TCP headers only
631 * once instead of for every generated packet.
633 if (!(flags & IP_FORWARDING) && ia) {
634 if (m->m_pkthdr.csum_flags & CSUM_TSO)
635 counter_u64_add(ia->ia_ifa.ifa_opackets,
636 m->m_pkthdr.len / m->m_pkthdr.tso_segsz);
638 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
640 counter_u64_add(ia->ia_ifa.ifa_obytes, m->m_pkthdr.len);
642 #ifdef MBUF_STRESS_TEST
643 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
644 m = m_fragment(m, M_NOWAIT, mbuf_frag_size);
647 * Reset layer specific mbuf flags
648 * to avoid confusing lower layers.
651 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
654 if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
655 in_pcboutput_txrtlmt(inp, ifp, m);
656 /* stamp send tag on mbuf */
657 m->m_pkthdr.snd_tag = inp->inp_snd_tag;
659 m->m_pkthdr.snd_tag = NULL;
662 error = (*ifp->if_output)(ifp, m,
663 (const struct sockaddr *)gw, ro);
665 /* check for route change */
667 in_pcboutput_eagain(inp);
672 /* Balk when DF bit is set or the interface didn't support TSO. */
673 if ((ip_off & IP_DF) || (m->m_pkthdr.csum_flags & CSUM_TSO)) {
675 IPSTAT_INC(ips_cantfrag);
680 * Too large for interface; fragment if possible. If successful,
681 * on return, m will point to a list of packets to be sent.
683 error = ip_fragment(ip, &m, mtu, ifp->if_hwassist);
690 /* Record statistics for this interface address. */
692 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
693 counter_u64_add(ia->ia_ifa.ifa_obytes,
697 * Reset layer specific mbuf flags
698 * to avoid confusing upper layers.
702 IP_PROBE(send, NULL, NULL, mtod(m, struct ip *), ifp,
703 mtod(m, struct ip *), NULL);
706 if (inp->inp_flags2 & INP_RATE_LIMIT_CHANGED)
707 in_pcboutput_txrtlmt(inp, ifp, m);
708 /* stamp send tag on mbuf */
709 m->m_pkthdr.snd_tag = inp->inp_snd_tag;
711 m->m_pkthdr.snd_tag = NULL;
714 error = (*ifp->if_output)(ifp, m,
715 (const struct sockaddr *)gw, ro);
717 /* check for route change */
719 in_pcboutput_eagain(inp);
726 IPSTAT_INC(ips_fragmented);
731 else if (rte == NULL)
733 * If the caller supplied a route but somehow the reference
734 * to it has been released need to prevent the caller
735 * calling RTFREE on it again.
739 ifa_free(&ia->ia_ifa);
747 * Create a chain of fragments which fit the given mtu. m_frag points to the
748 * mbuf to be fragmented; on return it points to the chain with the fragments.
749 * Return 0 if no error. If error, m_frag may contain a partially built
750 * chain of fragments that should be freed by the caller.
752 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
755 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
756 u_long if_hwassist_flags)
759 int hlen = ip->ip_hl << 2;
760 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
762 struct mbuf *m0 = *m_frag; /* the original packet */
766 uint16_t ip_len, ip_off;
768 ip_len = ntohs(ip->ip_len);
769 ip_off = ntohs(ip->ip_off);
771 if (ip_off & IP_DF) { /* Fragmentation not allowed */
772 IPSTAT_INC(ips_cantfrag);
777 * Must be able to put at least 8 bytes per fragment.
783 * If the interface will not calculate checksums on
784 * fragmented packets, then do it here.
786 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
787 in_delayed_cksum(m0);
788 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
791 if (m0->m_pkthdr.csum_flags & CSUM_SCTP) {
792 sctp_delayed_cksum(m0, hlen);
793 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
796 if (len > PAGE_SIZE) {
798 * Fragment large datagrams such that each segment
799 * contains a multiple of PAGE_SIZE amount of data,
800 * plus headers. This enables a receiver to perform
801 * page-flipping zero-copy optimizations.
803 * XXX When does this help given that sender and receiver
804 * could have different page sizes, and also mtu could
805 * be less than the receiver's page size ?
809 off = MIN(mtu, m0->m_pkthdr.len);
812 * firstlen (off - hlen) must be aligned on an
816 goto smart_frag_failure;
817 off = ((off - hlen) & ~7) + hlen;
818 newlen = (~PAGE_MASK) & mtu;
819 if ((newlen + sizeof (struct ip)) > mtu) {
820 /* we failed, go back the default */
831 firstlen = off - hlen;
832 mnext = &m0->m_nextpkt; /* pointer to next packet */
835 * Loop through length of segment after first fragment,
836 * make new header and copy data of each part and link onto chain.
837 * Here, m0 is the original packet, m is the fragment being created.
838 * The fragments are linked off the m_nextpkt of the original
839 * packet, which after processing serves as the first fragment.
841 for (nfrags = 1; off < ip_len; off += len, nfrags++) {
842 struct ip *mhip; /* ip header on the fragment */
844 int mhlen = sizeof (struct ip);
846 m = m_gethdr(M_NOWAIT, MT_DATA);
849 IPSTAT_INC(ips_odropped);
853 * Make sure the complete packet header gets copied
854 * from the originating mbuf to the newly created
855 * mbuf. This also ensures that existing firewall
856 * classification(s), VLAN tags and so on get copied
857 * to the resulting fragmented packet(s):
859 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
862 IPSTAT_INC(ips_odropped);
866 * In the first mbuf, leave room for the link header, then
867 * copy the original IP header including options. The payload
868 * goes into an additional mbuf chain returned by m_copym().
870 m->m_data += max_linkhdr;
871 mhip = mtod(m, struct ip *);
873 if (hlen > sizeof (struct ip)) {
874 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
875 mhip->ip_v = IPVERSION;
876 mhip->ip_hl = mhlen >> 2;
879 /* XXX do we need to add ip_off below ? */
880 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
881 if (off + len >= ip_len)
884 mhip->ip_off |= IP_MF;
885 mhip->ip_len = htons((u_short)(len + mhlen));
886 m->m_next = m_copym(m0, off, len, M_NOWAIT);
887 if (m->m_next == NULL) { /* copy failed */
889 error = ENOBUFS; /* ??? */
890 IPSTAT_INC(ips_odropped);
893 m->m_pkthdr.len = mhlen + len;
895 mac_netinet_fragment(m0, m);
897 mhip->ip_off = htons(mhip->ip_off);
899 if (m->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
900 mhip->ip_sum = in_cksum(m, mhlen);
901 m->m_pkthdr.csum_flags &= ~CSUM_IP;
904 mnext = &m->m_nextpkt;
906 IPSTAT_ADD(ips_ofragments, nfrags);
909 * Update first fragment by trimming what's been copied out
910 * and updating header.
912 m_adj(m0, hlen + firstlen - ip_len);
913 m0->m_pkthdr.len = hlen + firstlen;
914 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
915 ip->ip_off = htons(ip_off | IP_MF);
917 if (m0->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
918 ip->ip_sum = in_cksum(m0, hlen);
919 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
928 in_delayed_cksum(struct mbuf *m)
931 uint16_t csum, offset, ip_len;
933 ip = mtod(m, struct ip *);
934 offset = ip->ip_hl << 2 ;
935 ip_len = ntohs(ip->ip_len);
936 csum = in_cksum_skip(m, ip_len, offset);
937 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
939 offset += m->m_pkthdr.csum_data; /* checksum offset */
941 /* find the mbuf in the chain where the checksum starts*/
942 while ((m != NULL) && (offset >= m->m_len)) {
946 KASSERT(m != NULL, ("in_delayed_cksum: checksum outside mbuf chain."));
947 KASSERT(offset + sizeof(u_short) <= m->m_len, ("in_delayed_cksum: checksum split between mbufs."));
948 *(u_short *)(m->m_data + offset) = csum;
952 * IP socket option processing.
955 ip_ctloutput(struct socket *so, struct sockopt *sopt)
957 struct inpcb *inp = sotoinpcb(so);
965 if (sopt->sopt_level != IPPROTO_IP) {
968 if (sopt->sopt_level == SOL_SOCKET &&
969 sopt->sopt_dir == SOPT_SET) {
970 switch (sopt->sopt_name) {
973 if ((so->so_options & SO_REUSEADDR) != 0)
974 inp->inp_flags2 |= INP_REUSEADDR;
976 inp->inp_flags2 &= ~INP_REUSEADDR;
982 if ((so->so_options & SO_REUSEPORT) != 0)
983 inp->inp_flags2 |= INP_REUSEPORT;
985 inp->inp_flags2 &= ~INP_REUSEPORT;
991 inp->inp_inc.inc_fibnum = so->so_fibnum;
995 case SO_MAX_PACING_RATE:
998 inp->inp_flags2 |= INP_RATE_LIMIT_CHANGED;
1012 switch (sopt->sopt_dir) {
1014 switch (sopt->sopt_name) {
1021 if (sopt->sopt_valsize > MLEN) {
1025 m = m_get(sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
1030 m->m_len = sopt->sopt_valsize;
1031 error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1038 error = ip_pcbopts(inp, sopt->sopt_name, m);
1044 if (sopt->sopt_td != NULL) {
1045 error = priv_check(sopt->sopt_td,
1046 PRIV_NETINET_BINDANY);
1053 case IP_RSS_LISTEN_BUCKET:
1059 case IP_RECVRETOPTS:
1060 case IP_ORIGDSTADDR:
1061 case IP_RECVDSTADDR:
1069 case IP_RECVRSSBUCKETID:
1071 error = sooptcopyin(sopt, &optval, sizeof optval,
1076 switch (sopt->sopt_name) {
1078 inp->inp_ip_tos = optval;
1082 inp->inp_ip_ttl = optval;
1086 if (optval >= 0 && optval <= MAXTTL)
1087 inp->inp_ip_minttl = optval;
1092 #define OPTSET(bit) do { \
1095 inp->inp_flags |= bit; \
1097 inp->inp_flags &= ~bit; \
1101 #define OPTSET2(bit, val) do { \
1104 inp->inp_flags2 |= bit; \
1106 inp->inp_flags2 &= ~bit; \
1111 OPTSET(INP_RECVOPTS);
1114 case IP_RECVRETOPTS:
1115 OPTSET(INP_RECVRETOPTS);
1118 case IP_RECVDSTADDR:
1119 OPTSET(INP_RECVDSTADDR);
1122 case IP_ORIGDSTADDR:
1123 OPTSET2(INP_ORIGDSTADDR, optval);
1127 OPTSET(INP_RECVTTL);
1135 OPTSET(INP_ONESBCAST);
1138 OPTSET(INP_DONTFRAG);
1141 OPTSET(INP_BINDANY);
1144 OPTSET(INP_RECVTOS);
1147 OPTSET2(INP_BINDMULTI, optval);
1150 OPTSET2(INP_RECVFLOWID, optval);
1153 case IP_RSS_LISTEN_BUCKET:
1154 if ((optval >= 0) &&
1155 (optval < rss_getnumbuckets())) {
1156 inp->inp_rss_listen_bucket = optval;
1157 OPTSET2(INP_RSS_BUCKET_SET, 1);
1162 case IP_RECVRSSBUCKETID:
1163 OPTSET2(INP_RECVRSSBUCKETID, optval);
1172 * Multicast socket options are processed by the in_mcast
1175 case IP_MULTICAST_IF:
1176 case IP_MULTICAST_VIF:
1177 case IP_MULTICAST_TTL:
1178 case IP_MULTICAST_LOOP:
1179 case IP_ADD_MEMBERSHIP:
1180 case IP_DROP_MEMBERSHIP:
1181 case IP_ADD_SOURCE_MEMBERSHIP:
1182 case IP_DROP_SOURCE_MEMBERSHIP:
1183 case IP_BLOCK_SOURCE:
1184 case IP_UNBLOCK_SOURCE:
1186 case MCAST_JOIN_GROUP:
1187 case MCAST_LEAVE_GROUP:
1188 case MCAST_JOIN_SOURCE_GROUP:
1189 case MCAST_LEAVE_SOURCE_GROUP:
1190 case MCAST_BLOCK_SOURCE:
1191 case MCAST_UNBLOCK_SOURCE:
1192 error = inp_setmoptions(inp, sopt);
1196 error = sooptcopyin(sopt, &optval, sizeof optval,
1203 case IP_PORTRANGE_DEFAULT:
1204 inp->inp_flags &= ~(INP_LOWPORT);
1205 inp->inp_flags &= ~(INP_HIGHPORT);
1208 case IP_PORTRANGE_HIGH:
1209 inp->inp_flags &= ~(INP_LOWPORT);
1210 inp->inp_flags |= INP_HIGHPORT;
1213 case IP_PORTRANGE_LOW:
1214 inp->inp_flags &= ~(INP_HIGHPORT);
1215 inp->inp_flags |= INP_LOWPORT;
1225 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1226 case IP_IPSEC_POLICY:
1227 if (IPSEC_ENABLED(ipv4)) {
1228 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1235 error = ENOPROTOOPT;
1241 switch (sopt->sopt_name) {
1244 if (inp->inp_options)
1245 error = sooptcopyout(sopt,
1246 mtod(inp->inp_options,
1248 inp->inp_options->m_len);
1250 sopt->sopt_valsize = 0;
1257 case IP_RECVRETOPTS:
1258 case IP_ORIGDSTADDR:
1259 case IP_RECVDSTADDR:
1272 case IP_RSSBUCKETID:
1273 case IP_RECVRSSBUCKETID:
1275 switch (sopt->sopt_name) {
1278 optval = inp->inp_ip_tos;
1282 optval = inp->inp_ip_ttl;
1286 optval = inp->inp_ip_minttl;
1289 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1290 #define OPTBIT2(bit) (inp->inp_flags2 & bit ? 1 : 0)
1293 optval = OPTBIT(INP_RECVOPTS);
1296 case IP_RECVRETOPTS:
1297 optval = OPTBIT(INP_RECVRETOPTS);
1300 case IP_RECVDSTADDR:
1301 optval = OPTBIT(INP_RECVDSTADDR);
1304 case IP_ORIGDSTADDR:
1305 optval = OPTBIT2(INP_ORIGDSTADDR);
1309 optval = OPTBIT(INP_RECVTTL);
1313 optval = OPTBIT(INP_RECVIF);
1317 if (inp->inp_flags & INP_HIGHPORT)
1318 optval = IP_PORTRANGE_HIGH;
1319 else if (inp->inp_flags & INP_LOWPORT)
1320 optval = IP_PORTRANGE_LOW;
1326 optval = OPTBIT(INP_ONESBCAST);
1329 optval = OPTBIT(INP_DONTFRAG);
1332 optval = OPTBIT(INP_BINDANY);
1335 optval = OPTBIT(INP_RECVTOS);
1338 optval = inp->inp_flowid;
1341 optval = inp->inp_flowtype;
1344 optval = OPTBIT2(INP_RECVFLOWID);
1347 case IP_RSSBUCKETID:
1348 retval = rss_hash2bucket(inp->inp_flowid,
1352 optval = rss_bucket;
1356 case IP_RECVRSSBUCKETID:
1357 optval = OPTBIT2(INP_RECVRSSBUCKETID);
1361 optval = OPTBIT2(INP_BINDMULTI);
1364 error = sooptcopyout(sopt, &optval, sizeof optval);
1368 * Multicast socket options are processed by the in_mcast
1371 case IP_MULTICAST_IF:
1372 case IP_MULTICAST_VIF:
1373 case IP_MULTICAST_TTL:
1374 case IP_MULTICAST_LOOP:
1376 error = inp_getmoptions(inp, sopt);
1379 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1380 case IP_IPSEC_POLICY:
1381 if (IPSEC_ENABLED(ipv4)) {
1382 error = IPSEC_PCBCTL(ipv4, inp, sopt);
1389 error = ENOPROTOOPT;
1398 * Routine called from ip_output() to loop back a copy of an IP multicast
1399 * packet to the input queue of a specified interface. Note that this
1400 * calls the output routine of the loopback "driver", but with an interface
1401 * pointer that might NOT be a loopback interface -- evil, but easier than
1402 * replicating that code here.
1405 ip_mloopback(struct ifnet *ifp, const struct mbuf *m, int hlen)
1411 * Make a deep copy of the packet because we're going to
1412 * modify the pack in order to generate checksums.
1414 copym = m_dup(m, M_NOWAIT);
1415 if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen))
1416 copym = m_pullup(copym, hlen);
1417 if (copym != NULL) {
1418 /* If needed, compute the checksum and mark it as valid. */
1419 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1420 in_delayed_cksum(copym);
1421 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1422 copym->m_pkthdr.csum_flags |=
1423 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1424 copym->m_pkthdr.csum_data = 0xffff;
1427 * We don't bother to fragment if the IP length is greater
1428 * than the interface's MTU. Can this possibly matter?
1430 ip = mtod(copym, struct ip *);
1432 ip->ip_sum = in_cksum(copym, hlen);
1433 if_simloop(ifp, copym, AF_INET, 0);