2 * Copyright (c) 1982, 1986, 1988, 1990, 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
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22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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29 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
36 #include "opt_ipsec.h"
37 #include "opt_mbuf_stress_test.h"
38 #include "opt_mpath.h"
39 #include "opt_route.h"
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/kernel.h>
47 #include <sys/malloc.h>
51 #include <sys/protosw.h>
52 #include <sys/rmlock.h>
54 #include <sys/socket.h>
55 #include <sys/socketvar.h>
56 #include <sys/sysctl.h>
57 #include <sys/ucred.h>
60 #include <net/if_var.h>
61 #include <net/if_llatbl.h>
62 #include <net/netisr.h>
64 #include <net/route.h>
65 #include <net/flowtable.h>
67 #include <net/radix_mpath.h>
69 #include <net/rss_config.h>
72 #include <netinet/in.h>
73 #include <netinet/in_kdtrace.h>
74 #include <netinet/in_systm.h>
75 #include <netinet/ip.h>
76 #include <netinet/in_pcb.h>
77 #include <netinet/in_rss.h>
78 #include <netinet/in_var.h>
79 #include <netinet/ip_var.h>
80 #include <netinet/ip_options.h>
82 #include <netinet/sctp.h>
83 #include <netinet/sctp_crc32.h>
87 #include <netinet/ip_ipsec.h>
88 #include <netipsec/ipsec.h>
91 #include <machine/in_cksum.h>
93 #include <security/mac/mac_framework.h>
95 #ifdef MBUF_STRESS_TEST
96 static int mbuf_frag_size = 0;
97 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
98 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
101 static void ip_mloopback(struct ifnet *, const struct mbuf *, int);
104 extern int in_mcast_loop;
105 extern struct protosw inetsw[];
108 ip_output_pfil(struct mbuf **mp, struct ifnet *ifp, struct inpcb *inp,
109 struct sockaddr_in *dst, int *fibnum, int *error)
111 struct m_tag *fwd_tag = NULL;
117 ip = mtod(m, struct ip *);
119 /* Run through list of hooks for output packets. */
120 odst.s_addr = ip->ip_dst.s_addr;
121 *error = pfil_run_hooks(&V_inet_pfil_hook, mp, ifp, PFIL_OUT, inp);
123 if ((*error) != 0 || m == NULL)
124 return 1; /* Finished */
126 ip = mtod(m, struct ip *);
128 /* See if destination IP address was changed by packet filter. */
129 if (odst.s_addr != ip->ip_dst.s_addr) {
130 m->m_flags |= M_SKIP_FIREWALL;
131 /* If destination is now ourself drop to ip_input(). */
132 if (in_localip(ip->ip_dst)) {
133 m->m_flags |= M_FASTFWD_OURS;
134 if (m->m_pkthdr.rcvif == NULL)
135 m->m_pkthdr.rcvif = V_loif;
136 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
137 m->m_pkthdr.csum_flags |=
138 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
139 m->m_pkthdr.csum_data = 0xffff;
141 m->m_pkthdr.csum_flags |=
142 CSUM_IP_CHECKED | CSUM_IP_VALID;
144 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
145 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
147 *error = netisr_queue(NETISR_IP, m);
148 return 1; /* Finished */
151 bzero(dst, sizeof(*dst));
152 dst->sin_family = AF_INET;
153 dst->sin_len = sizeof(*dst);
154 dst->sin_addr = ip->ip_dst;
156 return -1; /* Reloop */
158 /* See if fib was changed by packet filter. */
159 if ((*fibnum) != M_GETFIB(m)) {
160 m->m_flags |= M_SKIP_FIREWALL;
161 *fibnum = M_GETFIB(m);
162 return -1; /* Reloop for FIB change */
165 /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
166 if (m->m_flags & M_FASTFWD_OURS) {
167 if (m->m_pkthdr.rcvif == NULL)
168 m->m_pkthdr.rcvif = V_loif;
169 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
170 m->m_pkthdr.csum_flags |=
171 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
172 m->m_pkthdr.csum_data = 0xffff;
175 if (m->m_pkthdr.csum_flags & CSUM_SCTP)
176 m->m_pkthdr.csum_flags |= CSUM_SCTP_VALID;
178 m->m_pkthdr.csum_flags |=
179 CSUM_IP_CHECKED | CSUM_IP_VALID;
181 *error = netisr_queue(NETISR_IP, m);
182 return 1; /* Finished */
184 /* Or forward to some other address? */
185 if ((m->m_flags & M_IP_NEXTHOP) &&
186 ((fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL)) != NULL)) {
187 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
188 m->m_flags |= M_SKIP_FIREWALL;
189 m->m_flags &= ~M_IP_NEXTHOP;
190 m_tag_delete(m, fwd_tag);
192 return -1; /* Reloop for CHANGE of dst */
199 * IP output. The packet in mbuf chain m contains a skeletal IP
200 * header (with len, off, ttl, proto, tos, src, dst).
201 * The mbuf chain containing the packet will be freed.
202 * The mbuf opt, if present, will not be freed.
203 * If route ro is present and has ro_rt initialized, route lookup would be
204 * skipped and ro->ro_rt would be used. If ro is present but ro->ro_rt is NULL,
205 * then result of route lookup is stored in ro->ro_rt.
207 * In the IP forwarding case, the packet will arrive with options already
208 * inserted, so must have a NULL opt pointer.
211 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
212 struct ip_moptions *imo, struct inpcb *inp)
214 struct rm_priotracker in_ifa_tracker;
216 struct ifnet *ifp = NULL; /* keep compiler happy */
218 int hlen = sizeof (struct ip);
221 struct sockaddr_in *dst;
222 const struct sockaddr_in *gw;
223 struct in_ifaddr *ia;
225 uint16_t ip_len, ip_off;
226 struct route iproute;
227 struct rtentry *rte; /* cache for ro->ro_rt */
231 int no_route_but_check_spd = 0;
236 INP_LOCK_ASSERT(inp);
237 M_SETFIB(m, inp->inp_inc.inc_fibnum);
238 if ((flags & IP_NODEFAULTFLOWID) == 0) {
239 m->m_pkthdr.flowid = inp->inp_flowid;
240 M_HASHTYPE_SET(m, inp->inp_flowtype);
246 bzero(ro, sizeof (*ro));
248 ro->ro_flags |= RT_LLE_CACHE;
251 if (ro->ro_rt == NULL)
252 (void )flowtable_lookup(AF_INET, m, ro);
257 m = ip_insertoptions(m, opt, &len);
259 hlen = len; /* ip->ip_hl is updated above */
261 ip = mtod(m, struct ip *);
262 ip_len = ntohs(ip->ip_len);
263 ip_off = ntohs(ip->ip_off);
265 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
266 ip->ip_v = IPVERSION;
267 ip->ip_hl = hlen >> 2;
269 IPSTAT_INC(ips_localout);
271 /* Header already set, fetch hlen from there */
272 hlen = ip->ip_hl << 2;
278 * dst can be rewritten but always points to &ro->ro_dst.
279 * gw is readonly but can point either to dst OR rt_gateway,
280 * therefore we need restore gw if we're redoing lookup.
282 gw = dst = (struct sockaddr_in *)&ro->ro_dst;
283 fibnum = (inp != NULL) ? inp->inp_inc.inc_fibnum : M_GETFIB(m);
286 bzero(dst, sizeof(*dst));
287 dst->sin_family = AF_INET;
288 dst->sin_len = sizeof(*dst);
289 dst->sin_addr = ip->ip_dst;
293 * Validate route against routing table additions;
294 * a better/more specific route might have been added.
297 RT_VALIDATE(ro, &inp->inp_rt_cookie, fibnum);
299 * If there is a cached route,
300 * check that it is to the same destination
301 * and is still up. If not, free it and try again.
302 * The address family should also be checked in case of sharing the
304 * Also check whether routing cache needs invalidation.
307 if (rte && ((rte->rt_flags & RTF_UP) == 0 ||
308 rte->rt_ifp == NULL ||
309 !RT_LINK_IS_UP(rte->rt_ifp) ||
310 dst->sin_family != AF_INET ||
311 dst->sin_addr.s_addr != ip->ip_dst.s_addr)) {
313 rte = ro->ro_rt = (struct rtentry *)NULL;
315 LLE_FREE(ro->ro_lle); /* zeros ro_lle */
316 ro->ro_lle = (struct llentry *)NULL;
321 * If routing to interface only, short circuit routing lookup.
322 * The use of an all-ones broadcast address implies this; an
323 * interface is specified by the broadcast address of an interface,
324 * or the destination address of a ptp interface.
326 if (flags & IP_SENDONES) {
327 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst),
328 M_GETFIB(m)))) == NULL &&
329 (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
330 M_GETFIB(m)))) == NULL) {
331 IPSTAT_INC(ips_noroute);
336 ip->ip_dst.s_addr = INADDR_BROADCAST;
337 dst->sin_addr = ip->ip_dst;
341 } else if (flags & IP_ROUTETOIF) {
342 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst),
343 M_GETFIB(m)))) == NULL &&
344 (ia = ifatoia(ifa_ifwithnet(sintosa(dst), 0,
345 M_GETFIB(m)))) == NULL) {
346 IPSTAT_INC(ips_noroute);
353 isbroadcast = in_ifaddr_broadcast(dst->sin_addr, ia);
354 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
355 imo != NULL && imo->imo_multicast_ifp != NULL) {
357 * Bypass the normal routing lookup for multicast
358 * packets if the interface is specified.
360 ifp = imo->imo_multicast_ifp;
361 IFP_TO_IA(ifp, ia, &in_ifa_tracker);
364 isbroadcast = 0; /* fool gcc */
367 * We want to do any cloning requested by the link layer,
368 * as this is probably required in all cases for correct
369 * operation (as it is for ARP).
373 rtalloc_mpath_fib(ro,
374 ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr),
377 in_rtalloc_ign(ro, 0, fibnum);
382 (rte->rt_flags & RTF_UP) == 0 ||
383 rte->rt_ifp == NULL ||
384 !RT_LINK_IS_UP(rte->rt_ifp)) {
387 * There is no route for this packet, but it is
388 * possible that a matching SPD entry exists.
390 no_route_but_check_spd = 1;
391 mtu = 0; /* Silence GCC warning. */
394 IPSTAT_INC(ips_noroute);
395 error = EHOSTUNREACH;
398 ia = ifatoia(rte->rt_ifa);
400 counter_u64_add(rte->rt_pksent, 1);
401 rt_update_ro_flags(ro);
402 if (rte->rt_flags & RTF_GATEWAY)
403 gw = (struct sockaddr_in *)rte->rt_gateway;
404 if (rte->rt_flags & RTF_HOST)
405 isbroadcast = (rte->rt_flags & RTF_BROADCAST);
407 isbroadcast = in_ifaddr_broadcast(gw->sin_addr, ia);
411 * Calculate MTU. If we have a route that is up, use that,
412 * otherwise use the interface's MTU.
414 if (rte != NULL && (rte->rt_flags & (RTF_UP|RTF_HOST)))
418 /* Catch a possible divide by zero later. */
419 KASSERT(mtu > 0, ("%s: mtu %d <= 0, rte=%p (rt_flags=0x%08x) ifp=%p",
420 __func__, mtu, rte, (rte != NULL) ? rte->rt_flags : 0, ifp));
422 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
423 m->m_flags |= M_MCAST;
425 * IP destination address is multicast. Make sure "gw"
426 * still points to the address in "ro". (It may have been
427 * changed to point to a gateway address, above.)
431 * See if the caller provided any multicast options
434 ip->ip_ttl = imo->imo_multicast_ttl;
435 if (imo->imo_multicast_vif != -1)
438 ip_mcast_src(imo->imo_multicast_vif) :
441 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
443 * Confirm that the outgoing interface supports multicast.
445 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
446 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
447 IPSTAT_INC(ips_noroute);
453 * If source address not specified yet, use address
454 * of outgoing interface.
456 if (ip->ip_src.s_addr == INADDR_ANY) {
457 /* Interface may have no addresses. */
459 ip->ip_src = IA_SIN(ia)->sin_addr;
462 if ((imo == NULL && in_mcast_loop) ||
463 (imo && imo->imo_multicast_loop)) {
465 * Loop back multicast datagram if not expressly
466 * forbidden to do so, even if we are not a member
467 * of the group; ip_input() will filter it later,
468 * thus deferring a hash lookup and mutex acquisition
469 * at the expense of a cheap copy using m_copym().
471 ip_mloopback(ifp, m, hlen);
474 * If we are acting as a multicast router, perform
475 * multicast forwarding as if the packet had just
476 * arrived on the interface to which we are about
477 * to send. The multicast forwarding function
478 * recursively calls this function, using the
479 * IP_FORWARDING flag to prevent infinite recursion.
481 * Multicasts that are looped back by ip_mloopback(),
482 * above, will be forwarded by the ip_input() routine,
485 if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
487 * If rsvp daemon is not running, do not
488 * set ip_moptions. This ensures that the packet
489 * is multicast and not just sent down one link
490 * as prescribed by rsvpd.
495 ip_mforward(ip, ifp, m, imo) != 0) {
503 * Multicasts with a time-to-live of zero may be looped-
504 * back, above, but must not be transmitted on a network.
505 * Also, multicasts addressed to the loopback interface
506 * are not sent -- the above call to ip_mloopback() will
507 * loop back a copy. ip_input() will drop the copy if
508 * this host does not belong to the destination group on
509 * the loopback interface.
511 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
520 * If the source address is not specified yet, use the address
521 * of the outoing interface.
523 if (ip->ip_src.s_addr == INADDR_ANY) {
524 /* Interface may have no addresses. */
526 ip->ip_src = IA_SIN(ia)->sin_addr;
531 * Look for broadcast address and
532 * verify user is allowed to send
536 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
537 error = EADDRNOTAVAIL;
540 if ((flags & IP_ALLOWBROADCAST) == 0) {
544 /* don't allow broadcast messages to be fragmented */
549 m->m_flags |= M_BCAST;
551 m->m_flags &= ~M_BCAST;
556 switch(ip_ipsec_output(&m, inp, &error)) {
563 break; /* Continue with packet processing. */
566 * Check if there was a route for this packet; return error if not.
568 if (no_route_but_check_spd) {
569 IPSTAT_INC(ips_noroute);
570 error = EHOSTUNREACH;
573 /* Update variables that are affected by ipsec4_output(). */
574 ip = mtod(m, struct ip *);
575 hlen = ip->ip_hl << 2;
578 /* Jump over all PFIL processing if hooks are not active. */
579 if (PFIL_HOOKED(&V_inet_pfil_hook)) {
580 switch (ip_output_pfil(&m, ifp, inp, dst, &fibnum, &error)) {
581 case 1: /* Finished */
584 case 0: /* Continue normally */
585 ip = mtod(m, struct ip *);
588 case -1: /* Need to try again */
589 /* Reset everything for a new round */
592 ifa_free(&ia->ia_ifa);
593 ro->ro_prepend = NULL;
596 ip = mtod(m, struct ip *);
602 /* 127/8 must not appear on wire - RFC1122. */
603 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
604 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
605 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
606 IPSTAT_INC(ips_badaddr);
607 error = EADDRNOTAVAIL;
612 m->m_pkthdr.csum_flags |= CSUM_IP;
613 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
615 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
618 if (m->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
619 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
620 m->m_pkthdr.csum_flags &= ~CSUM_SCTP;
625 * If small enough for interface, or the interface will take
626 * care of the fragmentation for us, we can just send directly.
629 (m->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
631 if (m->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
632 ip->ip_sum = in_cksum(m, hlen);
633 m->m_pkthdr.csum_flags &= ~CSUM_IP;
637 * Record statistics for this interface address.
638 * With CSUM_TSO the byte/packet count will be slightly
639 * incorrect because we count the IP+TCP headers only
640 * once instead of for every generated packet.
642 if (!(flags & IP_FORWARDING) && ia) {
643 if (m->m_pkthdr.csum_flags & CSUM_TSO)
644 counter_u64_add(ia->ia_ifa.ifa_opackets,
645 m->m_pkthdr.len / m->m_pkthdr.tso_segsz);
647 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
649 counter_u64_add(ia->ia_ifa.ifa_obytes, m->m_pkthdr.len);
651 #ifdef MBUF_STRESS_TEST
652 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
653 m = m_fragment(m, M_NOWAIT, mbuf_frag_size);
656 * Reset layer specific mbuf flags
657 * to avoid confusing lower layers.
660 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
661 error = (*ifp->if_output)(ifp, m,
662 (const struct sockaddr *)gw, ro);
666 /* Balk when DF bit is set or the interface didn't support TSO. */
667 if ((ip_off & IP_DF) || (m->m_pkthdr.csum_flags & CSUM_TSO)) {
669 IPSTAT_INC(ips_cantfrag);
674 * Too large for interface; fragment if possible. If successful,
675 * on return, m will point to a list of packets to be sent.
677 error = ip_fragment(ip, &m, mtu, ifp->if_hwassist);
684 /* Record statistics for this interface address. */
686 counter_u64_add(ia->ia_ifa.ifa_opackets, 1);
687 counter_u64_add(ia->ia_ifa.ifa_obytes,
691 * Reset layer specific mbuf flags
692 * to avoid confusing upper layers.
696 IP_PROBE(send, NULL, NULL, ip, ifp, ip, NULL);
697 error = (*ifp->if_output)(ifp, m,
698 (const struct sockaddr *)gw, ro);
704 IPSTAT_INC(ips_fragmented);
708 * Release the route if using our private route, or if
709 * (with flowtable) we don't have our own reference.
711 if (ro == &iproute || ro->ro_flags & RT_NORTREF)
713 else if (rte == NULL)
715 * If the caller supplied a route but somehow the reference
716 * to it has been released need to prevent the caller
717 * calling RTFREE on it again.
721 ifa_free(&ia->ia_ifa);
729 * Create a chain of fragments which fit the given mtu. m_frag points to the
730 * mbuf to be fragmented; on return it points to the chain with the fragments.
731 * Return 0 if no error. If error, m_frag may contain a partially built
732 * chain of fragments that should be freed by the caller.
734 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
737 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
738 u_long if_hwassist_flags)
741 int hlen = ip->ip_hl << 2;
742 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
744 struct mbuf *m0 = *m_frag; /* the original packet */
748 uint16_t ip_len, ip_off;
750 ip_len = ntohs(ip->ip_len);
751 ip_off = ntohs(ip->ip_off);
753 if (ip_off & IP_DF) { /* Fragmentation not allowed */
754 IPSTAT_INC(ips_cantfrag);
759 * Must be able to put at least 8 bytes per fragment.
765 * If the interface will not calculate checksums on
766 * fragmented packets, then do it here.
768 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
769 in_delayed_cksum(m0);
770 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
773 if (m0->m_pkthdr.csum_flags & CSUM_SCTP) {
774 sctp_delayed_cksum(m0, hlen);
775 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
778 if (len > PAGE_SIZE) {
780 * Fragment large datagrams such that each segment
781 * contains a multiple of PAGE_SIZE amount of data,
782 * plus headers. This enables a receiver to perform
783 * page-flipping zero-copy optimizations.
785 * XXX When does this help given that sender and receiver
786 * could have different page sizes, and also mtu could
787 * be less than the receiver's page size ?
791 off = MIN(mtu, m0->m_pkthdr.len);
794 * firstlen (off - hlen) must be aligned on an
798 goto smart_frag_failure;
799 off = ((off - hlen) & ~7) + hlen;
800 newlen = (~PAGE_MASK) & mtu;
801 if ((newlen + sizeof (struct ip)) > mtu) {
802 /* we failed, go back the default */
813 firstlen = off - hlen;
814 mnext = &m0->m_nextpkt; /* pointer to next packet */
817 * Loop through length of segment after first fragment,
818 * make new header and copy data of each part and link onto chain.
819 * Here, m0 is the original packet, m is the fragment being created.
820 * The fragments are linked off the m_nextpkt of the original
821 * packet, which after processing serves as the first fragment.
823 for (nfrags = 1; off < ip_len; off += len, nfrags++) {
824 struct ip *mhip; /* ip header on the fragment */
826 int mhlen = sizeof (struct ip);
828 m = m_gethdr(M_NOWAIT, MT_DATA);
831 IPSTAT_INC(ips_odropped);
835 * Make sure the complete packet header gets copied
836 * from the originating mbuf to the newly created
837 * mbuf. This also ensures that existing firewall
838 * classification(s), VLAN tags and so on get copied
839 * to the resulting fragmented packet(s):
841 if (m_dup_pkthdr(m, m0, M_NOWAIT) == 0) {
844 IPSTAT_INC(ips_odropped);
848 * In the first mbuf, leave room for the link header, then
849 * copy the original IP header including options. The payload
850 * goes into an additional mbuf chain returned by m_copym().
852 m->m_data += max_linkhdr;
853 mhip = mtod(m, struct ip *);
855 if (hlen > sizeof (struct ip)) {
856 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
857 mhip->ip_v = IPVERSION;
858 mhip->ip_hl = mhlen >> 2;
861 /* XXX do we need to add ip_off below ? */
862 mhip->ip_off = ((off - hlen) >> 3) + ip_off;
863 if (off + len >= ip_len)
866 mhip->ip_off |= IP_MF;
867 mhip->ip_len = htons((u_short)(len + mhlen));
868 m->m_next = m_copym(m0, off, len, M_NOWAIT);
869 if (m->m_next == NULL) { /* copy failed */
871 error = ENOBUFS; /* ??? */
872 IPSTAT_INC(ips_odropped);
875 m->m_pkthdr.len = mhlen + len;
877 mac_netinet_fragment(m0, m);
879 mhip->ip_off = htons(mhip->ip_off);
881 if (m->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
882 mhip->ip_sum = in_cksum(m, mhlen);
883 m->m_pkthdr.csum_flags &= ~CSUM_IP;
886 mnext = &m->m_nextpkt;
888 IPSTAT_ADD(ips_ofragments, nfrags);
891 * Update first fragment by trimming what's been copied out
892 * and updating header.
894 m_adj(m0, hlen + firstlen - ip_len);
895 m0->m_pkthdr.len = hlen + firstlen;
896 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
897 ip->ip_off = htons(ip_off | IP_MF);
899 if (m0->m_pkthdr.csum_flags & CSUM_IP & ~if_hwassist_flags) {
900 ip->ip_sum = in_cksum(m0, hlen);
901 m0->m_pkthdr.csum_flags &= ~CSUM_IP;
910 in_delayed_cksum(struct mbuf *m)
913 uint16_t csum, offset, ip_len;
915 ip = mtod(m, struct ip *);
916 offset = ip->ip_hl << 2 ;
917 ip_len = ntohs(ip->ip_len);
918 csum = in_cksum_skip(m, ip_len, offset);
919 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
921 offset += m->m_pkthdr.csum_data; /* checksum offset */
923 /* find the mbuf in the chain where the checksum starts*/
924 while ((m != NULL) && (offset >= m->m_len)) {
928 KASSERT(m != NULL, ("in_delayed_cksum: checksum outside mbuf chain."));
929 KASSERT(offset + sizeof(u_short) <= m->m_len, ("in_delayed_cksum: checksum split between mbufs."));
930 *(u_short *)(m->m_data + offset) = csum;
934 * IP socket option processing.
937 ip_ctloutput(struct socket *so, struct sockopt *sopt)
939 struct inpcb *inp = sotoinpcb(so);
947 if (sopt->sopt_level != IPPROTO_IP) {
950 if (sopt->sopt_level == SOL_SOCKET &&
951 sopt->sopt_dir == SOPT_SET) {
952 switch (sopt->sopt_name) {
955 if ((so->so_options & SO_REUSEADDR) != 0)
956 inp->inp_flags2 |= INP_REUSEADDR;
958 inp->inp_flags2 &= ~INP_REUSEADDR;
964 if ((so->so_options & SO_REUSEPORT) != 0)
965 inp->inp_flags2 |= INP_REUSEPORT;
967 inp->inp_flags2 &= ~INP_REUSEPORT;
973 inp->inp_inc.inc_fibnum = so->so_fibnum;
984 switch (sopt->sopt_dir) {
986 switch (sopt->sopt_name) {
993 if (sopt->sopt_valsize > MLEN) {
997 m = m_get(sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_DATA);
1002 m->m_len = sopt->sopt_valsize;
1003 error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1010 error = ip_pcbopts(inp, sopt->sopt_name, m);
1016 if (sopt->sopt_td != NULL) {
1017 error = priv_check(sopt->sopt_td,
1018 PRIV_NETINET_BINDANY);
1025 case IP_RSS_LISTEN_BUCKET:
1031 case IP_RECVRETOPTS:
1032 case IP_RECVDSTADDR:
1040 case IP_RECVRSSBUCKETID:
1042 error = sooptcopyin(sopt, &optval, sizeof optval,
1047 switch (sopt->sopt_name) {
1049 inp->inp_ip_tos = optval;
1053 inp->inp_ip_ttl = optval;
1057 if (optval >= 0 && optval <= MAXTTL)
1058 inp->inp_ip_minttl = optval;
1063 #define OPTSET(bit) do { \
1066 inp->inp_flags |= bit; \
1068 inp->inp_flags &= ~bit; \
1072 #define OPTSET2(bit, val) do { \
1075 inp->inp_flags2 |= bit; \
1077 inp->inp_flags2 &= ~bit; \
1082 OPTSET(INP_RECVOPTS);
1085 case IP_RECVRETOPTS:
1086 OPTSET(INP_RECVRETOPTS);
1089 case IP_RECVDSTADDR:
1090 OPTSET(INP_RECVDSTADDR);
1094 OPTSET(INP_RECVTTL);
1102 OPTSET(INP_ONESBCAST);
1105 OPTSET(INP_DONTFRAG);
1108 OPTSET(INP_BINDANY);
1111 OPTSET(INP_RECVTOS);
1114 OPTSET2(INP_BINDMULTI, optval);
1117 OPTSET2(INP_RECVFLOWID, optval);
1120 case IP_RSS_LISTEN_BUCKET:
1121 if ((optval >= 0) &&
1122 (optval < rss_getnumbuckets())) {
1123 inp->inp_rss_listen_bucket = optval;
1124 OPTSET2(INP_RSS_BUCKET_SET, 1);
1129 case IP_RECVRSSBUCKETID:
1130 OPTSET2(INP_RECVRSSBUCKETID, optval);
1139 * Multicast socket options are processed by the in_mcast
1142 case IP_MULTICAST_IF:
1143 case IP_MULTICAST_VIF:
1144 case IP_MULTICAST_TTL:
1145 case IP_MULTICAST_LOOP:
1146 case IP_ADD_MEMBERSHIP:
1147 case IP_DROP_MEMBERSHIP:
1148 case IP_ADD_SOURCE_MEMBERSHIP:
1149 case IP_DROP_SOURCE_MEMBERSHIP:
1150 case IP_BLOCK_SOURCE:
1151 case IP_UNBLOCK_SOURCE:
1153 case MCAST_JOIN_GROUP:
1154 case MCAST_LEAVE_GROUP:
1155 case MCAST_JOIN_SOURCE_GROUP:
1156 case MCAST_LEAVE_SOURCE_GROUP:
1157 case MCAST_BLOCK_SOURCE:
1158 case MCAST_UNBLOCK_SOURCE:
1159 error = inp_setmoptions(inp, sopt);
1163 error = sooptcopyin(sopt, &optval, sizeof optval,
1170 case IP_PORTRANGE_DEFAULT:
1171 inp->inp_flags &= ~(INP_LOWPORT);
1172 inp->inp_flags &= ~(INP_HIGHPORT);
1175 case IP_PORTRANGE_HIGH:
1176 inp->inp_flags &= ~(INP_LOWPORT);
1177 inp->inp_flags |= INP_HIGHPORT;
1180 case IP_PORTRANGE_LOW:
1181 inp->inp_flags &= ~(INP_HIGHPORT);
1182 inp->inp_flags |= INP_LOWPORT;
1193 case IP_IPSEC_POLICY:
1198 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1200 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1202 req = mtod(m, caddr_t);
1203 error = ipsec_set_policy(inp, sopt->sopt_name, req,
1204 m->m_len, (sopt->sopt_td != NULL) ?
1205 sopt->sopt_td->td_ucred : NULL);
1212 error = ENOPROTOOPT;
1218 switch (sopt->sopt_name) {
1221 if (inp->inp_options)
1222 error = sooptcopyout(sopt,
1223 mtod(inp->inp_options,
1225 inp->inp_options->m_len);
1227 sopt->sopt_valsize = 0;
1234 case IP_RECVRETOPTS:
1235 case IP_RECVDSTADDR:
1248 case IP_RSSBUCKETID:
1249 case IP_RECVRSSBUCKETID:
1251 switch (sopt->sopt_name) {
1254 optval = inp->inp_ip_tos;
1258 optval = inp->inp_ip_ttl;
1262 optval = inp->inp_ip_minttl;
1265 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1266 #define OPTBIT2(bit) (inp->inp_flags2 & bit ? 1 : 0)
1269 optval = OPTBIT(INP_RECVOPTS);
1272 case IP_RECVRETOPTS:
1273 optval = OPTBIT(INP_RECVRETOPTS);
1276 case IP_RECVDSTADDR:
1277 optval = OPTBIT(INP_RECVDSTADDR);
1281 optval = OPTBIT(INP_RECVTTL);
1285 optval = OPTBIT(INP_RECVIF);
1289 if (inp->inp_flags & INP_HIGHPORT)
1290 optval = IP_PORTRANGE_HIGH;
1291 else if (inp->inp_flags & INP_LOWPORT)
1292 optval = IP_PORTRANGE_LOW;
1298 optval = OPTBIT(INP_ONESBCAST);
1301 optval = OPTBIT(INP_DONTFRAG);
1304 optval = OPTBIT(INP_BINDANY);
1307 optval = OPTBIT(INP_RECVTOS);
1310 optval = inp->inp_flowid;
1313 optval = inp->inp_flowtype;
1316 optval = OPTBIT2(INP_RECVFLOWID);
1319 case IP_RSSBUCKETID:
1320 retval = rss_hash2bucket(inp->inp_flowid,
1324 optval = rss_bucket;
1328 case IP_RECVRSSBUCKETID:
1329 optval = OPTBIT2(INP_RECVRSSBUCKETID);
1333 optval = OPTBIT2(INP_BINDMULTI);
1336 error = sooptcopyout(sopt, &optval, sizeof optval);
1340 * Multicast socket options are processed by the in_mcast
1343 case IP_MULTICAST_IF:
1344 case IP_MULTICAST_VIF:
1345 case IP_MULTICAST_TTL:
1346 case IP_MULTICAST_LOOP:
1348 error = inp_getmoptions(inp, sopt);
1352 case IP_IPSEC_POLICY:
1354 struct mbuf *m = NULL;
1359 req = mtod(m, caddr_t);
1362 error = ipsec_get_policy(sotoinpcb(so), req, len, &m);
1364 error = soopt_mcopyout(sopt, m); /* XXX */
1372 error = ENOPROTOOPT;
1381 * Routine called from ip_output() to loop back a copy of an IP multicast
1382 * packet to the input queue of a specified interface. Note that this
1383 * calls the output routine of the loopback "driver", but with an interface
1384 * pointer that might NOT be a loopback interface -- evil, but easier than
1385 * replicating that code here.
1388 ip_mloopback(struct ifnet *ifp, const struct mbuf *m, int hlen)
1394 * Make a deep copy of the packet because we're going to
1395 * modify the pack in order to generate checksums.
1397 copym = m_dup(m, M_NOWAIT);
1398 if (copym != NULL && (!M_WRITABLE(copym) || copym->m_len < hlen))
1399 copym = m_pullup(copym, hlen);
1400 if (copym != NULL) {
1401 /* If needed, compute the checksum and mark it as valid. */
1402 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1403 in_delayed_cksum(copym);
1404 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1405 copym->m_pkthdr.csum_flags |=
1406 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1407 copym->m_pkthdr.csum_data = 0xffff;
1410 * We don't bother to fragment if the IP length is greater
1411 * than the interface's MTU. Can this possibly matter?
1413 ip = mtod(copym, struct ip *);
1415 ip->ip_sum = in_cksum(copym, hlen);
1416 if_simloop(ifp, copym, AF_INET, 0);