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
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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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_output.c 8.3 (Berkeley) 1/21/94
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
36 #include "opt_ipsec.h"
38 #include "opt_mbuf_stress_test.h"
39 #include "opt_mpath.h"
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/malloc.h>
48 #include <sys/protosw.h>
49 #include <sys/socket.h>
50 #include <sys/socketvar.h>
51 #include <sys/sysctl.h>
52 #include <sys/ucred.h>
53 #include <sys/vimage.h>
56 #include <net/netisr.h>
58 #include <net/route.h>
60 #include <net/radix_mpath.h>
63 #include <netinet/in.h>
64 #include <netinet/in_systm.h>
65 #include <netinet/ip.h>
66 #include <netinet/in_pcb.h>
67 #include <netinet/in_var.h>
68 #include <netinet/ip_var.h>
69 #include <netinet/ip_options.h>
72 #include <netinet/ip_ipsec.h>
73 #include <netipsec/ipsec.h>
76 #include <machine/in_cksum.h>
78 #include <security/mac/mac_framework.h>
80 #define print_ip(x, a, y) printf("%s %d.%d.%d.%d%s",\
81 x, (ntohl(a.s_addr)>>24)&0xFF,\
82 (ntohl(a.s_addr)>>16)&0xFF,\
83 (ntohl(a.s_addr)>>8)&0xFF,\
84 (ntohl(a.s_addr))&0xFF, y);
88 #ifdef MBUF_STRESS_TEST
89 int mbuf_frag_size = 0;
90 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
91 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
94 static void ip_mloopback
95 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int);
98 extern struct protosw inetsw[];
101 * IP output. The packet in mbuf chain m contains a skeletal IP
102 * header (with len, off, ttl, proto, tos, src, dst).
103 * The mbuf chain containing the packet will be freed.
104 * The mbuf opt, if present, will not be freed.
105 * In the IP forwarding case, the packet will arrive with options already
106 * inserted, so must have a NULL opt pointer.
109 ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
110 struct ip_moptions *imo, struct inpcb *inp)
112 INIT_VNET_NET(curvnet);
113 INIT_VNET_INET(curvnet);
115 struct ifnet *ifp = NULL; /* keep compiler happy */
117 int hlen = sizeof (struct ip);
120 struct sockaddr_in *dst = NULL; /* keep compiler happy */
121 struct in_ifaddr *ia = NULL;
122 int isbroadcast, sw_csum;
123 struct route iproute;
125 #ifdef IPFIREWALL_FORWARD
126 struct m_tag *fwd_tag = NULL;
132 bzero(ro, sizeof (*ro));
136 INP_LOCK_ASSERT(inp);
140 m = ip_insertoptions(m, opt, &len);
144 ip = mtod(m, struct ip *);
147 * Fill in IP header. If we are not allowing fragmentation,
148 * then the ip_id field is meaningless, but we don't set it
149 * to zero. Doing so causes various problems when devices along
150 * the path (routers, load balancers, firewalls, etc.) illegally
151 * disable DF on our packet. Note that a 16-bit counter
152 * will wrap around in less than 10 seconds at 100 Mbit/s on a
153 * medium with MTU 1500. See Steven M. Bellovin, "A Technique
154 * for Counting NATted Hosts", Proc. IMW'02, available at
155 * <http://www.cs.columbia.edu/~smb/papers/fnat.pdf>.
157 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
158 ip->ip_v = IPVERSION;
159 ip->ip_hl = hlen >> 2;
160 ip->ip_id = ip_newid();
161 V_ipstat.ips_localout++;
163 hlen = ip->ip_hl << 2;
166 dst = (struct sockaddr_in *)&ro->ro_dst;
169 * If there is a cached route,
170 * check that it is to the same destination
171 * and is still up. If not, free it and try again.
172 * The address family should also be checked in case of sharing the
175 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
176 dst->sin_family != AF_INET ||
177 dst->sin_addr.s_addr != ip->ip_dst.s_addr)) {
179 ro->ro_rt = (struct rtentry *)NULL;
181 #ifdef IPFIREWALL_FORWARD
182 if (ro->ro_rt == NULL && fwd_tag == NULL) {
184 if (ro->ro_rt == NULL) {
186 bzero(dst, sizeof(*dst));
187 dst->sin_family = AF_INET;
188 dst->sin_len = sizeof(*dst);
189 dst->sin_addr = ip->ip_dst;
192 * If routing to interface only, short circuit routing lookup.
193 * The use of an all-ones broadcast address implies this; an
194 * interface is specified by the broadcast address of an interface,
195 * or the destination address of a ptp interface.
197 if (flags & IP_SENDONES) {
198 if ((ia = ifatoia(ifa_ifwithbroadaddr(sintosa(dst)))) == NULL &&
199 (ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL) {
200 V_ipstat.ips_noroute++;
204 ip->ip_dst.s_addr = INADDR_BROADCAST;
205 dst->sin_addr = ip->ip_dst;
209 } else if (flags & IP_ROUTETOIF) {
210 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL &&
211 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) {
212 V_ipstat.ips_noroute++;
218 isbroadcast = in_broadcast(dst->sin_addr, ifp);
219 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
220 imo != NULL && imo->imo_multicast_ifp != NULL) {
222 * Bypass the normal routing lookup for multicast
223 * packets if the interface is specified.
225 ifp = imo->imo_multicast_ifp;
227 isbroadcast = 0; /* fool gcc */
230 * We want to do any cloning requested by the link layer,
231 * as this is probably required in all cases for correct
232 * operation (as it is for ARP).
234 if (ro->ro_rt == NULL)
236 rtalloc_mpath_fib(ro,
237 ntohl(ip->ip_src.s_addr ^ ip->ip_dst.s_addr),
238 inp ? inp->inp_inc.inc_fibnum : M_GETFIB(m));
240 in_rtalloc_ign(ro, 0,
241 inp ? inp->inp_inc.inc_fibnum : M_GETFIB(m));
243 if (ro->ro_rt == NULL) {
244 V_ipstat.ips_noroute++;
245 error = EHOSTUNREACH;
248 ia = ifatoia(ro->ro_rt->rt_ifa);
249 ifp = ro->ro_rt->rt_ifp;
250 ro->ro_rt->rt_rmx.rmx_pksent++;
251 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
252 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
253 if (ro->ro_rt->rt_flags & RTF_HOST)
254 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
256 isbroadcast = in_broadcast(dst->sin_addr, ifp);
259 * Calculate MTU. If we have a route that is up, use that,
260 * otherwise use the interface's MTU.
262 if (ro->ro_rt != NULL && (ro->ro_rt->rt_flags & (RTF_UP|RTF_HOST))) {
264 * This case can happen if the user changed the MTU
265 * of an interface after enabling IP on it. Because
266 * most netifs don't keep track of routes pointing to
267 * them, there is no way for one to update all its
268 * routes when the MTU is changed.
270 if (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)
271 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
272 mtu = ro->ro_rt->rt_rmx.rmx_mtu;
276 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
277 struct in_multi *inm;
279 m->m_flags |= M_MCAST;
281 * IP destination address is multicast. Make sure "dst"
282 * still points to the address in "ro". (It may have been
283 * changed to point to a gateway address, above.)
285 dst = (struct sockaddr_in *)&ro->ro_dst;
287 * See if the caller provided any multicast options
290 ip->ip_ttl = imo->imo_multicast_ttl;
291 if (imo->imo_multicast_vif != -1)
294 ip_mcast_src(imo->imo_multicast_vif) :
297 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
299 * Confirm that the outgoing interface supports multicast.
301 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
302 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
303 V_ipstat.ips_noroute++;
309 * If source address not specified yet, use address
310 * of outgoing interface.
312 if (ip->ip_src.s_addr == INADDR_ANY) {
313 /* Interface may have no addresses. */
315 ip->ip_src = IA_SIN(ia)->sin_addr;
319 IN_LOOKUP_MULTI(ip->ip_dst, ifp, inm);
321 (imo == NULL || imo->imo_multicast_loop)) {
324 * If we belong to the destination multicast group
325 * on the outgoing interface, and the caller did not
326 * forbid loopback, loop back a copy.
328 ip_mloopback(ifp, m, dst, hlen);
333 * If we are acting as a multicast router, perform
334 * multicast forwarding as if the packet had just
335 * arrived on the interface to which we are about
336 * to send. The multicast forwarding function
337 * recursively calls this function, using the
338 * IP_FORWARDING flag to prevent infinite recursion.
340 * Multicasts that are looped back by ip_mloopback(),
341 * above, will be forwarded by the ip_input() routine,
344 if (V_ip_mrouter && (flags & IP_FORWARDING) == 0) {
346 * If rsvp daemon is not running, do not
347 * set ip_moptions. This ensures that the packet
348 * is multicast and not just sent down one link
349 * as prescribed by rsvpd.
354 ip_mforward(ip, ifp, m, imo) != 0) {
362 * Multicasts with a time-to-live of zero may be looped-
363 * back, above, but must not be transmitted on a network.
364 * Also, multicasts addressed to the loopback interface
365 * are not sent -- the above call to ip_mloopback() will
366 * loop back a copy if this host actually belongs to the
367 * destination group on the loopback interface.
369 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
378 * If the source address is not specified yet, use the address
379 * of the outoing interface.
381 if (ip->ip_src.s_addr == INADDR_ANY) {
382 /* Interface may have no addresses. */
384 ip->ip_src = IA_SIN(ia)->sin_addr;
389 * Verify that we have any chance at all of being able to queue the
390 * packet or packet fragments, unless ALTQ is enabled on the given
391 * interface in which case packetdrop should be done by queueing.
394 if ((!ALTQ_IS_ENABLED(&ifp->if_snd)) &&
395 ((ifp->if_snd.ifq_len + ip->ip_len / mtu + 1) >=
396 ifp->if_snd.ifq_maxlen))
398 if ((ifp->if_snd.ifq_len + ip->ip_len / mtu + 1) >=
399 ifp->if_snd.ifq_maxlen)
403 V_ipstat.ips_odropped++;
404 ifp->if_snd.ifq_drops += (ip->ip_len / ifp->if_mtu + 1);
409 * Look for broadcast address and
410 * verify user is allowed to send
414 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
415 error = EADDRNOTAVAIL;
418 if ((flags & IP_ALLOWBROADCAST) == 0) {
422 /* don't allow broadcast messages to be fragmented */
423 if (ip->ip_len > mtu) {
427 m->m_flags |= M_BCAST;
429 m->m_flags &= ~M_BCAST;
434 switch(ip_ipsec_output(&m, inp, &flags, &error, &ro, &iproute, &dst, &ia, &ifp)) {
441 break; /* Continue with packet processing. */
443 /* Update variables that are affected by ipsec4_output(). */
444 ip = mtod(m, struct ip *);
445 hlen = ip->ip_hl << 2;
448 /* Jump over all PFIL processing if hooks are not active. */
449 if (!PFIL_HOOKED(&inet_pfil_hook))
452 /* Run through list of hooks for output packets. */
453 odst.s_addr = ip->ip_dst.s_addr;
454 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT, inp);
455 if (error != 0 || m == NULL)
458 ip = mtod(m, struct ip *);
460 /* See if destination IP address was changed by packet filter. */
461 if (odst.s_addr != ip->ip_dst.s_addr) {
462 m->m_flags |= M_SKIP_FIREWALL;
463 /* If destination is now ourself drop to ip_input(). */
464 if (in_localip(ip->ip_dst)) {
465 m->m_flags |= M_FASTFWD_OURS;
466 if (m->m_pkthdr.rcvif == NULL)
467 m->m_pkthdr.rcvif = V_loif;
468 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
469 m->m_pkthdr.csum_flags |=
470 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
471 m->m_pkthdr.csum_data = 0xffff;
473 m->m_pkthdr.csum_flags |=
474 CSUM_IP_CHECKED | CSUM_IP_VALID;
476 error = netisr_queue(NETISR_IP, m);
479 goto again; /* Redo the routing table lookup. */
482 #ifdef IPFIREWALL_FORWARD
483 /* See if local, if yes, send it to netisr with IP_FASTFWD_OURS. */
484 if (m->m_flags & M_FASTFWD_OURS) {
485 if (m->m_pkthdr.rcvif == NULL)
486 m->m_pkthdr.rcvif = V_loif;
487 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
488 m->m_pkthdr.csum_flags |=
489 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
490 m->m_pkthdr.csum_data = 0xffff;
492 m->m_pkthdr.csum_flags |=
493 CSUM_IP_CHECKED | CSUM_IP_VALID;
495 error = netisr_queue(NETISR_IP, m);
498 /* Or forward to some other address? */
499 fwd_tag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
501 dst = (struct sockaddr_in *)&ro->ro_dst;
502 bcopy((fwd_tag+1), dst, sizeof(struct sockaddr_in));
503 m->m_flags |= M_SKIP_FIREWALL;
504 m_tag_delete(m, fwd_tag);
507 #endif /* IPFIREWALL_FORWARD */
510 /* 127/8 must not appear on wire - RFC1122. */
511 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
512 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
513 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
514 V_ipstat.ips_badaddr++;
515 error = EADDRNOTAVAIL;
520 m->m_pkthdr.csum_flags |= CSUM_IP;
521 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
522 if (sw_csum & CSUM_DELAY_DATA) {
524 sw_csum &= ~CSUM_DELAY_DATA;
526 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
529 * If small enough for interface, or the interface will take
530 * care of the fragmentation for us, we can just send directly.
532 if (ip->ip_len <= mtu ||
533 (m->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0 ||
534 ((ip->ip_off & IP_DF) == 0 && (ifp->if_hwassist & CSUM_FRAGMENT))) {
535 ip->ip_len = htons(ip->ip_len);
536 ip->ip_off = htons(ip->ip_off);
538 if (sw_csum & CSUM_DELAY_IP)
539 ip->ip_sum = in_cksum(m, hlen);
542 * Record statistics for this interface address.
543 * With CSUM_TSO the byte/packet count will be slightly
544 * incorrect because we count the IP+TCP headers only
545 * once instead of for every generated packet.
547 if (!(flags & IP_FORWARDING) && ia) {
548 if (m->m_pkthdr.csum_flags & CSUM_TSO)
549 ia->ia_ifa.if_opackets +=
550 m->m_pkthdr.len / m->m_pkthdr.tso_segsz;
552 ia->ia_ifa.if_opackets++;
553 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
555 #ifdef MBUF_STRESS_TEST
556 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size)
557 m = m_fragment(m, M_DONTWAIT, mbuf_frag_size);
560 * Reset layer specific mbuf flags
561 * to avoid confusing lower layers.
563 m->m_flags &= ~(M_PROTOFLAGS);
565 error = (*ifp->if_output)(ifp, m,
566 (struct sockaddr *)dst, ro->ro_rt);
570 /* Balk when DF bit is set or the interface didn't support TSO. */
571 if ((ip->ip_off & IP_DF) || (m->m_pkthdr.csum_flags & CSUM_TSO)) {
573 V_ipstat.ips_cantfrag++;
578 * Too large for interface; fragment if possible. If successful,
579 * on return, m will point to a list of packets to be sent.
581 error = ip_fragment(ip, &m, mtu, ifp->if_hwassist, sw_csum);
588 /* Record statistics for this interface address. */
590 ia->ia_ifa.if_opackets++;
591 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
594 * Reset layer specific mbuf flags
595 * to avoid confusing upper layers.
597 m->m_flags &= ~(M_PROTOFLAGS);
599 error = (*ifp->if_output)(ifp, m,
600 (struct sockaddr *)dst, ro->ro_rt);
606 V_ipstat.ips_fragmented++;
609 if (ro == &iproute && ro->ro_rt) {
619 * Create a chain of fragments which fit the given mtu. m_frag points to the
620 * mbuf to be fragmented; on return it points to the chain with the fragments.
621 * Return 0 if no error. If error, m_frag may contain a partially built
622 * chain of fragments that should be freed by the caller.
624 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
625 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
628 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
629 u_long if_hwassist_flags, int sw_csum)
631 INIT_VNET_INET(curvnet);
633 int hlen = ip->ip_hl << 2;
634 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
636 struct mbuf *m0 = *m_frag; /* the original packet */
641 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */
642 V_ipstat.ips_cantfrag++;
647 * Must be able to put at least 8 bytes per fragment.
653 * If the interface will not calculate checksums on
654 * fragmented packets, then do it here.
656 if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA &&
657 (if_hwassist_flags & CSUM_IP_FRAGS) == 0) {
658 in_delayed_cksum(m0);
659 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
662 if (len > PAGE_SIZE) {
664 * Fragment large datagrams such that each segment
665 * contains a multiple of PAGE_SIZE amount of data,
666 * plus headers. This enables a receiver to perform
667 * page-flipping zero-copy optimizations.
669 * XXX When does this help given that sender and receiver
670 * could have different page sizes, and also mtu could
671 * be less than the receiver's page size ?
676 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next)
680 * firstlen (off - hlen) must be aligned on an
684 goto smart_frag_failure;
685 off = ((off - hlen) & ~7) + hlen;
686 newlen = (~PAGE_MASK) & mtu;
687 if ((newlen + sizeof (struct ip)) > mtu) {
688 /* we failed, go back the default */
699 firstlen = off - hlen;
700 mnext = &m0->m_nextpkt; /* pointer to next packet */
703 * Loop through length of segment after first fragment,
704 * make new header and copy data of each part and link onto chain.
705 * Here, m0 is the original packet, m is the fragment being created.
706 * The fragments are linked off the m_nextpkt of the original
707 * packet, which after processing serves as the first fragment.
709 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) {
710 struct ip *mhip; /* ip header on the fragment */
712 int mhlen = sizeof (struct ip);
714 MGETHDR(m, M_DONTWAIT, MT_DATA);
717 V_ipstat.ips_odropped++;
720 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
722 * In the first mbuf, leave room for the link header, then
723 * copy the original IP header including options. The payload
724 * goes into an additional mbuf chain returned by m_copy().
726 m->m_data += max_linkhdr;
727 mhip = mtod(m, struct ip *);
729 if (hlen > sizeof (struct ip)) {
730 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
731 mhip->ip_v = IPVERSION;
732 mhip->ip_hl = mhlen >> 2;
735 /* XXX do we need to add ip->ip_off below ? */
736 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
737 if (off + len >= ip->ip_len) { /* last fragment */
738 len = ip->ip_len - off;
739 m->m_flags |= M_LASTFRAG;
741 mhip->ip_off |= IP_MF;
742 mhip->ip_len = htons((u_short)(len + mhlen));
743 m->m_next = m_copy(m0, off, len);
744 if (m->m_next == NULL) { /* copy failed */
746 error = ENOBUFS; /* ??? */
747 V_ipstat.ips_odropped++;
750 m->m_pkthdr.len = mhlen + len;
751 m->m_pkthdr.rcvif = NULL;
753 mac_netinet_fragment(m0, m);
755 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
756 mhip->ip_off = htons(mhip->ip_off);
758 if (sw_csum & CSUM_DELAY_IP)
759 mhip->ip_sum = in_cksum(m, mhlen);
761 mnext = &m->m_nextpkt;
763 V_ipstat.ips_ofragments += nfrags;
765 /* set first marker for fragment chain */
766 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
767 m0->m_pkthdr.csum_data = nfrags;
770 * Update first fragment by trimming what's been copied out
771 * and updating header.
773 m_adj(m0, hlen + firstlen - ip->ip_len);
774 m0->m_pkthdr.len = hlen + firstlen;
775 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
777 ip->ip_off = htons(ip->ip_off);
779 if (sw_csum & CSUM_DELAY_IP)
780 ip->ip_sum = in_cksum(m0, hlen);
788 in_delayed_cksum(struct mbuf *m)
791 u_short csum, offset;
793 ip = mtod(m, struct ip *);
794 offset = ip->ip_hl << 2 ;
795 csum = in_cksum_skip(m, ip->ip_len, offset);
796 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
798 offset += m->m_pkthdr.csum_data; /* checksum offset */
800 if (offset + sizeof(u_short) > m->m_len) {
801 printf("delayed m_pullup, m->len: %d off: %d p: %d\n",
802 m->m_len, offset, ip->ip_p);
805 * this shouldn't happen, but if it does, the
806 * correct behavior may be to insert the checksum
807 * in the appropriate next mbuf in the chain.
811 *(u_short *)(m->m_data + offset) = csum;
815 * IP socket option processing.
818 ip_ctloutput(struct socket *so, struct sockopt *sopt)
820 struct inpcb *inp = sotoinpcb(so);
824 if (sopt->sopt_level != IPPROTO_IP) {
828 switch (sopt->sopt_dir) {
830 switch (sopt->sopt_name) {
837 if (sopt->sopt_valsize > MLEN) {
841 MGET(m, sopt->sopt_td ? M_WAIT : M_DONTWAIT, MT_DATA);
846 m->m_len = sopt->sopt_valsize;
847 error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
854 error = ip_pcbopts(inp, sopt->sopt_name, m);
870 error = sooptcopyin(sopt, &optval, sizeof optval,
875 switch (sopt->sopt_name) {
877 inp->inp_ip_tos = optval;
881 inp->inp_ip_ttl = optval;
885 if (optval > 0 && optval <= MAXTTL)
886 inp->inp_ip_minttl = optval;
891 #define OPTSET(bit) do { \
894 inp->inp_flags |= bit; \
896 inp->inp_flags &= ~bit; \
901 OPTSET(INP_RECVOPTS);
905 OPTSET(INP_RECVRETOPTS);
909 OPTSET(INP_RECVDSTADDR);
925 OPTSET(INP_ONESBCAST);
928 OPTSET(INP_DONTFRAG);
935 * Multicast socket options are processed by the in_mcast
938 case IP_MULTICAST_IF:
939 case IP_MULTICAST_VIF:
940 case IP_MULTICAST_TTL:
941 case IP_MULTICAST_LOOP:
942 case IP_ADD_MEMBERSHIP:
943 case IP_DROP_MEMBERSHIP:
944 case IP_ADD_SOURCE_MEMBERSHIP:
945 case IP_DROP_SOURCE_MEMBERSHIP:
946 case IP_BLOCK_SOURCE:
947 case IP_UNBLOCK_SOURCE:
949 case MCAST_JOIN_GROUP:
950 case MCAST_LEAVE_GROUP:
951 case MCAST_JOIN_SOURCE_GROUP:
952 case MCAST_LEAVE_SOURCE_GROUP:
953 case MCAST_BLOCK_SOURCE:
954 case MCAST_UNBLOCK_SOURCE:
955 error = inp_setmoptions(inp, sopt);
959 error = sooptcopyin(sopt, &optval, sizeof optval,
966 case IP_PORTRANGE_DEFAULT:
967 inp->inp_flags &= ~(INP_LOWPORT);
968 inp->inp_flags &= ~(INP_HIGHPORT);
971 case IP_PORTRANGE_HIGH:
972 inp->inp_flags &= ~(INP_LOWPORT);
973 inp->inp_flags |= INP_HIGHPORT;
976 case IP_PORTRANGE_LOW:
977 inp->inp_flags &= ~(INP_HIGHPORT);
978 inp->inp_flags |= INP_LOWPORT;
989 case IP_IPSEC_POLICY:
994 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
996 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
998 req = mtod(m, caddr_t);
999 error = ipsec4_set_policy(inp, sopt->sopt_name, req,
1000 m->m_len, (sopt->sopt_td != NULL) ?
1001 sopt->sopt_td->td_ucred : NULL);
1008 error = ENOPROTOOPT;
1014 switch (sopt->sopt_name) {
1017 if (inp->inp_options)
1018 error = sooptcopyout(sopt,
1019 mtod(inp->inp_options,
1021 inp->inp_options->m_len);
1023 sopt->sopt_valsize = 0;
1030 case IP_RECVRETOPTS:
1031 case IP_RECVDSTADDR:
1038 switch (sopt->sopt_name) {
1041 optval = inp->inp_ip_tos;
1045 optval = inp->inp_ip_ttl;
1049 optval = inp->inp_ip_minttl;
1052 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1055 optval = OPTBIT(INP_RECVOPTS);
1058 case IP_RECVRETOPTS:
1059 optval = OPTBIT(INP_RECVRETOPTS);
1062 case IP_RECVDSTADDR:
1063 optval = OPTBIT(INP_RECVDSTADDR);
1067 optval = OPTBIT(INP_RECVTTL);
1071 optval = OPTBIT(INP_RECVIF);
1075 if (inp->inp_flags & INP_HIGHPORT)
1076 optval = IP_PORTRANGE_HIGH;
1077 else if (inp->inp_flags & INP_LOWPORT)
1078 optval = IP_PORTRANGE_LOW;
1084 optval = OPTBIT(INP_FAITH);
1088 optval = OPTBIT(INP_ONESBCAST);
1091 optval = OPTBIT(INP_DONTFRAG);
1094 error = sooptcopyout(sopt, &optval, sizeof optval);
1098 * Multicast socket options are processed by the in_mcast
1101 case IP_MULTICAST_IF:
1102 case IP_MULTICAST_VIF:
1103 case IP_MULTICAST_TTL:
1104 case IP_MULTICAST_LOOP:
1106 error = inp_getmoptions(inp, sopt);
1110 case IP_IPSEC_POLICY:
1112 struct mbuf *m = NULL;
1117 req = mtod(m, caddr_t);
1120 error = ipsec4_get_policy(sotoinpcb(so), req, len, &m);
1122 error = soopt_mcopyout(sopt, m); /* XXX */
1130 error = ENOPROTOOPT;
1139 * Routine called from ip_output() to loop back a copy of an IP multicast
1140 * packet to the input queue of a specified interface. Note that this
1141 * calls the output routine of the loopback "driver", but with an interface
1142 * pointer that might NOT be a loopback interface -- evil, but easier than
1143 * replicating that code here.
1146 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst,
1149 register struct ip *ip;
1153 * Make a deep copy of the packet because we're going to
1154 * modify the pack in order to generate checksums.
1156 copym = m_dup(m, M_DONTWAIT);
1157 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
1158 copym = m_pullup(copym, hlen);
1159 if (copym != NULL) {
1160 /* If needed, compute the checksum and mark it as valid. */
1161 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
1162 in_delayed_cksum(copym);
1163 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1164 copym->m_pkthdr.csum_flags |=
1165 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1166 copym->m_pkthdr.csum_data = 0xffff;
1169 * We don't bother to fragment if the IP length is greater
1170 * than the interface's MTU. Can this possibly matter?
1172 ip = mtod(copym, struct ip *);
1173 ip->ip_len = htons(ip->ip_len);
1174 ip->ip_off = htons(ip->ip_off);
1176 ip->ip_sum = in_cksum(copym, hlen);
1178 if (dst->sin_family != AF_INET) {
1179 printf("ip_mloopback: bad address family %d\n",
1181 dst->sin_family = AF_INET;
1184 if_simloop(ifp, copym, dst->sin_family, 0);