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get mxge to build, stage 29/many
[dragonfly.git] / sys / netinet / ip_output.c
blobab53a0f73cf5b95f4dfc2e94a5465dcceb74834a
1 /*
2 * Copyright (c) 1982, 1986, 1988, 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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 * 3. 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.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
30 * $FreeBSD: src/sys/netinet/ip_output.c,v 1.99.2.37 2003/04/15 06:44:45 silby Exp $
31 * $DragonFly: src/sys/netinet/ip_output.c,v 1.67 2008/10/28 03:07:28 sephe Exp $
32 */
33
34 #define _IP_VHL
35
36 #include "opt_ipfw.h"
37 #include "opt_ipdn.h"
38 #include "opt_ipdivert.h"
39 #include "opt_ipfilter.h"
40 #include "opt_ipsec.h"
41 #include "opt_mbuf_stress_test.h"
42 #include "opt_mpls.h"
43
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/malloc.h>
48 #include <sys/mbuf.h>
49 #include <sys/protosw.h>
50 #include <sys/socket.h>
51 #include <sys/socketvar.h>
52 #include <sys/proc.h>
53 #include <sys/priv.h>
54 #include <sys/sysctl.h>
55 #include <sys/thread2.h>
56 #include <sys/in_cksum.h>
57 #include <sys/lock.h>
58
59 #include <net/if.h>
60 #include <net/netisr.h>
61 #include <net/pfil.h>
62 #include <net/route.h>
63
64 #include <netinet/in.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/ip.h>
67 #include <netinet/in_pcb.h>
68 #include <netinet/in_var.h>
69 #include <netinet/ip_var.h>
70
71 #include <netproto/mpls/mpls_var.h>
72
73 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options");
74
75 #ifdef IPSEC
76 #include <netinet6/ipsec.h>
77 #include <netproto/key/key.h>
78 #ifdef IPSEC_DEBUG
79 #include <netproto/key/key_debug.h>
80 #else
81 #define KEYDEBUG(lev,arg)
82 #endif
83 #endif /*IPSEC*/
84
85 #ifdef FAST_IPSEC
86 #include <netproto/ipsec/ipsec.h>
87 #include <netproto/ipsec/xform.h>
88 #include <netproto/ipsec/key.h>
89 #endif /*FAST_IPSEC*/
90
91 #include <net/ipfw/ip_fw.h>
92 #include <net/dummynet/ip_dummynet.h>
93
94 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\
95 x, (ntohl(a.s_addr)>>24)&0xFF,\
96 (ntohl(a.s_addr)>>16)&0xFF,\
97 (ntohl(a.s_addr)>>8)&0xFF,\
98 (ntohl(a.s_addr))&0xFF, y);
99
100 u_short ip_id;
101
102 #ifdef MBUF_STRESS_TEST
103 int mbuf_frag_size = 0;
104 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
105 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
106 #endif
107
108 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *);
109 static struct ifnet *ip_multicast_if(struct in_addr *, int *);
110 static void ip_mloopback
111 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int);
112 static int ip_getmoptions
113 (struct sockopt *, struct ip_moptions *);
114 static int ip_pcbopts(int, struct mbuf **, struct mbuf *);
115 static int ip_setmoptions
116 (struct sockopt *, struct ip_moptions **);
117
118 int ip_optcopy(struct ip *, struct ip *);
119
120 extern int route_assert_owner_access;
121
122 extern struct protosw inetsw[];
123
124 static int
125 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst, int hlen)
126 {
127 struct in_ifaddr_container *iac;
128
129 /*
130 * We need to figure out if we have been forwarded to a local
131 * socket. If so, then we should somehow "loop back" to
132 * ip_input(), and get directed to the PCB as if we had received
133 * this packet. This is because it may be difficult to identify
134 * the packets you want to forward until they are being output
135 * and have selected an interface (e.g. locally initiated
136 * packets). If we used the loopback inteface, we would not be
137 * able to control what happens as the packet runs through
138 * ip_input() as it is done through a ISR.
139 */
140 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) {
141 /*
142 * If the addr to forward to is one of ours, we pretend
143 * to be the destination for this packet.
144 */
145 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr)
146 break;
147 }
148 if (iac != NULL) {
149 struct ip *ip;
150
151 if (m->m_pkthdr.rcvif == NULL)
152 m->m_pkthdr.rcvif = ifunit("lo0");
153 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
154 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID |
155 CSUM_PSEUDO_HDR;
156 m->m_pkthdr.csum_data = 0xffff;
157 }
158 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID;
159
160 /*
161 * Make sure that the IP header is in one mbuf,
162 * required by ip_input
163 */
164 if (m->m_len < hlen) {
165 m = m_pullup(m, hlen);
166 if (m == NULL) {
167 /* The packet was freed; we are done */
168 return 1;
169 }
170 }
171 ip = mtod(m, struct ip *);
172
173 ip->ip_len = htons(ip->ip_len);
174 ip->ip_off = htons(ip->ip_off);
175 ip_input(m);
176
177 return 1; /* The packet gets forwarded locally */
178 }
179 return 0;
180 }
181
182 /*
183 * IP output. The packet in mbuf chain m contains a skeletal IP
184 * header (with len, off, ttl, proto, tos, src, dst).
185 * The mbuf chain containing the packet will be freed.
186 * The mbuf opt, if present, will not be freed.
187 */
188 int
189 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro,
190 int flags, struct ip_moptions *imo, struct inpcb *inp)
191 {
192 struct ip *ip;
193 struct ifnet *ifp = NULL; /* keep compiler happy */
194 struct mbuf *m;
195 int hlen = sizeof(struct ip);
196 int len, error = 0;
197 struct sockaddr_in *dst = NULL; /* keep compiler happy */
198 struct in_ifaddr *ia = NULL;
199 int isbroadcast, sw_csum;
200 struct in_addr pkt_dst;
201 struct route iproute;
202 struct m_tag *mtag;
203 #ifdef IPSEC
204 struct secpolicy *sp = NULL;
205 struct socket *so = inp ? inp->inp_socket : NULL;
206 #endif
207 #ifdef FAST_IPSEC
208 struct secpolicy *sp = NULL;
209 struct tdb_ident *tdbi;
210 #endif /* FAST_IPSEC */
211 struct sockaddr_in *next_hop = NULL;
212 int src_was_INADDR_ANY = 0; /* as the name says... */
213
214 m = m0;
215 M_ASSERTPKTHDR(m);
216
217 if (ro == NULL) {
218 ro = &iproute;
219 bzero(ro, sizeof *ro);
220 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) {
221 if (flags & IP_DEBUGROUTE) {
222 if (route_assert_owner_access) {
223 panic("ip_output: "
224 "rt rt_cpuid %d accessed on cpu %d\n",
225 ro->ro_rt->rt_cpuid, mycpuid);
226 } else {
227 kprintf("ip_output: "
228 "rt rt_cpuid %d accessed on cpu %d\n",
229 ro->ro_rt->rt_cpuid, mycpuid);
230 print_backtrace();
231 }
232 }
233
234 /*
235 * XXX
236 * If the cached rtentry's owner CPU is not the current CPU,
237 * then don't touch the cached rtentry (remote free is too
238 * expensive in this context); just relocate the route.
239 */
240 ro = &iproute;
241 bzero(ro, sizeof *ro);
242 }
243
244 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
245 /* Next hop */
246 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
247 KKASSERT(mtag != NULL);
248 next_hop = m_tag_data(mtag);
249 }
250
251 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
252 struct dn_pkt *dn_pkt;
253
254 /* Extract info from dummynet tag */
255 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
256 KKASSERT(mtag != NULL);
257 dn_pkt = m_tag_data(mtag);
258
259 /*
260 * The packet was already tagged, so part of the
261 * processing was already done, and we need to go down.
262 * Get the calculated parameters from the tag.
263 */
264 ifp = dn_pkt->ifp;
265
266 KKASSERT(ro == &iproute);
267 *ro = dn_pkt->ro; /* structure copy */
268 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid);
269
270 dst = dn_pkt->dn_dst;
271 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) {
272 /* If 'dst' points into dummynet tag, adjust it */
273 dst = (struct sockaddr_in *)&(ro->ro_dst);
274 }
275
276 ip = mtod(m, struct ip *);
277 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ;
278 if (ro->ro_rt)
279 ia = ifatoia(ro->ro_rt->rt_ifa);
280 goto sendit;
281 }
282
283 if (opt) {
284 len = 0;
285 m = ip_insertoptions(m, opt, &len);
286 if (len != 0)
287 hlen = len;
288 }
289 ip = mtod(m, struct ip *);
290
291 /*
292 * Fill in IP header.
293 */
294 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) {
295 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2);
296 ip->ip_off &= IP_DF;
297 ip->ip_id = ip_newid();
298 ipstat.ips_localout++;
299 } else {
300 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
301 }
302
303 reroute:
304 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst;
305
306 #ifdef INVARIANTS
307 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
308 /*
309 * XXX
310 * Multicast is not MPSAFE yet. Caller must hold
311 * BGL when output a multicast IP packet.
312 */
313 ASSERT_MP_LOCK_HELD(curthread);
314 }
315 #endif
316
317 dst = (struct sockaddr_in *)&ro->ro_dst;
318 /*
319 * If there is a cached route,
320 * check that it is to the same destination
321 * and is still up. If not, free it and try again.
322 * The address family should also be checked in case of sharing the
323 * cache with IPv6.
324 */
325 if (ro->ro_rt &&
326 (!(ro->ro_rt->rt_flags & RTF_UP) ||
327 dst->sin_family != AF_INET ||
328 dst->sin_addr.s_addr != pkt_dst.s_addr)) {
329 rtfree(ro->ro_rt);
330 ro->ro_rt = NULL;
331 }
332 if (ro->ro_rt == NULL) {
333 bzero(dst, sizeof *dst);
334 dst->sin_family = AF_INET;
335 dst->sin_len = sizeof *dst;
336 dst->sin_addr = pkt_dst;
337 }
338 /*
339 * If routing to interface only,
340 * short circuit routing lookup.
341 */
342 if (flags & IP_ROUTETOIF) {
343 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL &&
344 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) {
345 ipstat.ips_noroute++;
346 error = ENETUNREACH;
347 goto bad;
348 }
349 ifp = ia->ia_ifp;
350 ip->ip_ttl = 1;
351 isbroadcast = in_broadcast(dst->sin_addr, ifp);
352 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) &&
353 imo != NULL && imo->imo_multicast_ifp != NULL) {
354 /*
355 * Bypass the normal routing lookup for multicast
356 * packets if the interface is specified.
357 */
358 ifp = imo->imo_multicast_ifp;
359 ia = IFP_TO_IA(ifp);
360 isbroadcast = 0; /* fool gcc */
361 } else {
362 /*
363 * If this is the case, we probably don't want to allocate
364 * a protocol-cloned route since we didn't get one from the
365 * ULP. This lets TCP do its thing, while not burdening
366 * forwarding or ICMP with the overhead of cloning a route.
367 * Of course, we still want to do any cloning requested by
368 * the link layer, as this is probably required in all cases
369 * for correct operation (as it is for ARP).
370 */
371 if (ro->ro_rt == NULL)
372 rtalloc_ign(ro, RTF_PRCLONING);
373 if (ro->ro_rt == NULL) {
374 ipstat.ips_noroute++;
375 error = EHOSTUNREACH;
376 goto bad;
377 }
378 ia = ifatoia(ro->ro_rt->rt_ifa);
379 ifp = ro->ro_rt->rt_ifp;
380 ro->ro_rt->rt_use++;
381 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
382 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
383 if (ro->ro_rt->rt_flags & RTF_HOST)
384 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
385 else
386 isbroadcast = in_broadcast(dst->sin_addr, ifp);
387 }
388 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
389 struct in_multi *inm;
390
391 m->m_flags |= M_MCAST;
392 /*
393 * IP destination address is multicast. Make sure "dst"
394 * still points to the address in "ro". (It may have been
395 * changed to point to a gateway address, above.)
396 */
397 dst = (struct sockaddr_in *)&ro->ro_dst;
398 /*
399 * See if the caller provided any multicast options
400 */
401 if (imo != NULL) {
402 ip->ip_ttl = imo->imo_multicast_ttl;
403 if (imo->imo_multicast_vif != -1) {
404 ip->ip_src.s_addr =
405 ip_mcast_src ?
406 ip_mcast_src(imo->imo_multicast_vif) :
407 INADDR_ANY;
408 }
409 } else {
410 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
411 }
412 /*
413 * Confirm that the outgoing interface supports multicast.
414 */
415 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
416 if (!(ifp->if_flags & IFF_MULTICAST)) {
417 ipstat.ips_noroute++;
418 error = ENETUNREACH;
419 goto bad;
420 }
421 }
422 /*
423 * If source address not specified yet, use address
424 * of outgoing interface.
425 */
426 if (ip->ip_src.s_addr == INADDR_ANY) {
427 /* Interface may have no addresses. */
428 if (ia != NULL)
429 ip->ip_src = IA_SIN(ia)->sin_addr;
430 }
431
432 IN_LOOKUP_MULTI(pkt_dst, ifp, inm);
433 if (inm != NULL &&
434 (imo == NULL || imo->imo_multicast_loop)) {
435 /*
436 * If we belong to the destination multicast group
437 * on the outgoing interface, and the caller did not
438 * forbid loopback, loop back a copy.
439 */
440 ip_mloopback(ifp, m, dst, hlen);
441 } else {
442 /*
443 * If we are acting as a multicast router, perform
444 * multicast forwarding as if the packet had just
445 * arrived on the interface to which we are about
446 * to send. The multicast forwarding function
447 * recursively calls this function, using the
448 * IP_FORWARDING flag to prevent infinite recursion.
449 *
450 * Multicasts that are looped back by ip_mloopback(),
451 * above, will be forwarded by the ip_input() routine,
452 * if necessary.
453 */
454 if (ip_mrouter && !(flags & IP_FORWARDING)) {
455 /*
456 * If rsvp daemon is not running, do not
457 * set ip_moptions. This ensures that the packet
458 * is multicast and not just sent down one link
459 * as prescribed by rsvpd.
460 */
461 if (!rsvp_on)
462 imo = NULL;
463 if (ip_mforward &&
464 ip_mforward(ip, ifp, m, imo) != 0) {
465 m_freem(m);
466 goto done;
467 }
468 }
469 }
470
471 /*
472 * Multicasts with a time-to-live of zero may be looped-
473 * back, above, but must not be transmitted on a network.
474 * Also, multicasts addressed to the loopback interface
475 * are not sent -- the above call to ip_mloopback() will
476 * loop back a copy if this host actually belongs to the
477 * destination group on the loopback interface.
478 */
479 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
480 m_freem(m);
481 goto done;
482 }
483
484 goto sendit;
485 } else {
486 m->m_flags &= ~M_MCAST;
487 }
488
489 /*
490 * If the source address is not specified yet, use the address
491 * of the outoing interface. In case, keep note we did that, so
492 * if the the firewall changes the next-hop causing the output
493 * interface to change, we can fix that.
494 */
495 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
496 /* Interface may have no addresses. */
497 if (ia != NULL) {
498 ip->ip_src = IA_SIN(ia)->sin_addr;
499 src_was_INADDR_ANY = 1;
500 }
501 }
502
503 #ifdef ALTQ
504 /*
505 * Disable packet drop hack.
506 * Packetdrop should be done by queueing.
507 */
508 #else /* !ALTQ */
509 /*
510 * Verify that we have any chance at all of being able to queue
511 * the packet or packet fragments
512 */
513 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >=
514 ifp->if_snd.ifq_maxlen) {
515 error = ENOBUFS;
516 ipstat.ips_odropped++;
517 goto bad;
518 }
519 #endif /* !ALTQ */
520
521 /*
522 * Look for broadcast address and
523 * verify user is allowed to send
524 * such a packet.
525 */
526 if (isbroadcast) {
527 if (!(ifp->if_flags & IFF_BROADCAST)) {
528 error = EADDRNOTAVAIL;
529 goto bad;
530 }
531 if (!(flags & IP_ALLOWBROADCAST)) {
532 error = EACCES;
533 goto bad;
534 }
535 /* don't allow broadcast messages to be fragmented */
536 if (ip->ip_len > ifp->if_mtu) {
537 error = EMSGSIZE;
538 goto bad;
539 }
540 m->m_flags |= M_BCAST;
541 } else {
542 m->m_flags &= ~M_BCAST;
543 }
544
545 sendit:
546 #ifdef IPSEC
547 /* get SP for this packet */
548 if (so == NULL)
549 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error);
550 else
551 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
552
553 if (sp == NULL) {
554 ipsecstat.out_inval++;
555 goto bad;
556 }
557
558 error = 0;
559
560 /* check policy */
561 switch (sp->policy) {
562 case IPSEC_POLICY_DISCARD:
563 /*
564 * This packet is just discarded.
565 */
566 ipsecstat.out_polvio++;
567 goto bad;
568
569 case IPSEC_POLICY_BYPASS:
570 case IPSEC_POLICY_NONE:
571 /* no need to do IPsec. */
572 goto skip_ipsec;
573
574 case IPSEC_POLICY_IPSEC:
575 if (sp->req == NULL) {
576 /* acquire a policy */
577 error = key_spdacquire(sp);
578 goto bad;
579 }
580 break;
581
582 case IPSEC_POLICY_ENTRUST:
583 default:
584 kprintf("ip_output: Invalid policy found. %d\n", sp->policy);
585 }
586 {
587 struct ipsec_output_state state;
588 bzero(&state, sizeof state);
589 state.m = m;
590 if (flags & IP_ROUTETOIF) {
591 state.ro = &iproute;
592 bzero(&iproute, sizeof iproute);
593 } else
594 state.ro = ro;
595 state.dst = (struct sockaddr *)dst;
596
597 ip->ip_sum = 0;
598
599 /*
600 * XXX
601 * delayed checksums are not currently compatible with IPsec
602 */
603 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
604 in_delayed_cksum(m);
605 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
606 }
607
608 ip->ip_len = htons(ip->ip_len);
609 ip->ip_off = htons(ip->ip_off);
610
611 error = ipsec4_output(&state, sp, flags);
612
613 m = state.m;
614 if (flags & IP_ROUTETOIF) {
615 /*
616 * if we have tunnel mode SA, we may need to ignore
617 * IP_ROUTETOIF.
618 */
619 if (state.ro != &iproute || state.ro->ro_rt != NULL) {
620 flags &= ~IP_ROUTETOIF;
621 ro = state.ro;
622 }
623 } else
624 ro = state.ro;
625 dst = (struct sockaddr_in *)state.dst;
626 if (error) {
627 /* mbuf is already reclaimed in ipsec4_output. */
628 m0 = NULL;
629 switch (error) {
630 case EHOSTUNREACH:
631 case ENETUNREACH:
632 case EMSGSIZE:
633 case ENOBUFS:
634 case ENOMEM:
635 break;
636 default:
637 kprintf("ip4_output (ipsec): error code %d\n", error);
638 /*fall through*/
639 case ENOENT:
640 /* don't show these error codes to the user */
641 error = 0;
642 break;
643 }
644 goto bad;
645 }
646 }
647
648 /* be sure to update variables that are affected by ipsec4_output() */
649 ip = mtod(m, struct ip *);
650 #ifdef _IP_VHL
651 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
652 #else
653 hlen = ip->ip_hl << 2;
654 #endif
655 if (ro->ro_rt == NULL) {
656 if (!(flags & IP_ROUTETOIF)) {
657 kprintf("ip_output: "
658 "can't update route after IPsec processing\n");
659 error = EHOSTUNREACH; /*XXX*/
660 goto bad;
661 }
662 } else {
663 ia = ifatoia(ro->ro_rt->rt_ifa);
664 ifp = ro->ro_rt->rt_ifp;
665 }
666
667 /* make it flipped, again. */
668 ip->ip_len = ntohs(ip->ip_len);
669 ip->ip_off = ntohs(ip->ip_off);
670 skip_ipsec:
671 #endif /*IPSEC*/
672 #ifdef FAST_IPSEC
673 /*
674 * Check the security policy (SP) for the packet and, if
675 * required, do IPsec-related processing. There are two
676 * cases here; the first time a packet is sent through
677 * it will be untagged and handled by ipsec4_checkpolicy.
678 * If the packet is resubmitted to ip_output (e.g. after
679 * AH, ESP, etc. processing), there will be a tag to bypass
680 * the lookup and related policy checking.
681 */
682 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
683 crit_enter();
684 if (mtag != NULL) {
685 tdbi = (struct tdb_ident *)m_tag_data(mtag);
686 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
687 if (sp == NULL)
688 error = -EINVAL; /* force silent drop */
689 m_tag_delete(m, mtag);
690 } else {
691 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags,
692 &error, inp);
693 }
694 /*
695 * There are four return cases:
696 * sp != NULL apply IPsec policy
697 * sp == NULL, error == 0 no IPsec handling needed
698 * sp == NULL, error == -EINVAL discard packet w/o error
699 * sp == NULL, error != 0 discard packet, report error
700 */
701 if (sp != NULL) {
702 /* Loop detection, check if ipsec processing already done */
703 KASSERT(sp->req != NULL, ("ip_output: no ipsec request"));
704 for (mtag = m_tag_first(m); mtag != NULL;
705 mtag = m_tag_next(m, mtag)) {
706 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
707 continue;
708 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
709 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
710 continue;
711 /*
712 * Check if policy has an SA associated with it.
713 * This can happen when an SP has yet to acquire
714 * an SA; e.g. on first reference. If it occurs,
715 * then we let ipsec4_process_packet do its thing.
716 */
717 if (sp->req->sav == NULL)
718 break;
719 tdbi = (struct tdb_ident *)m_tag_data(mtag);
720 if (tdbi->spi == sp->req->sav->spi &&
721 tdbi->proto == sp->req->sav->sah->saidx.proto &&
722 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst,
723 sizeof(union sockaddr_union)) == 0) {
724 /*
725 * No IPsec processing is needed, free
726 * reference to SP.
727 *
728 * NB: null pointer to avoid free at
729 * done: below.
730 */
731 KEY_FREESP(&sp), sp = NULL;
732 crit_exit();
733 goto spd_done;
734 }
735 }
736
737 /*
738 * Do delayed checksums now because we send before
739 * this is done in the normal processing path.
740 */
741 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
742 in_delayed_cksum(m);
743 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
744 }
745
746 ip->ip_len = htons(ip->ip_len);
747 ip->ip_off = htons(ip->ip_off);
748
749 /* NB: callee frees mbuf */
750 error = ipsec4_process_packet(m, sp->req, flags, 0);
751 /*
752 * Preserve KAME behaviour: ENOENT can be returned
753 * when an SA acquire is in progress. Don't propagate
754 * this to user-level; it confuses applications.
755 *
756 * XXX this will go away when the SADB is redone.
757 */
758 if (error == ENOENT)
759 error = 0;
760 crit_exit();
761 goto done;
762 } else {
763 crit_exit();
764
765 if (error != 0) {
766 /*
767 * Hack: -EINVAL is used to signal that a packet
768 * should be silently discarded. This is typically
769 * because we asked key management for an SA and
770 * it was delayed (e.g. kicked up to IKE).
771 */
772 if (error == -EINVAL)
773 error = 0;
774 goto bad;
775 } else {
776 /* No IPsec processing for this packet. */
777 }
778 #ifdef notyet
779 /*
780 * If deferred crypto processing is needed, check that
781 * the interface supports it.
782 */
783 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL);
784 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) {
785 /* notify IPsec to do its own crypto */
786 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag));
787 error = EHOSTUNREACH;
788 goto bad;
789 }
790 #endif
791 }
792 spd_done:
793 #endif /* FAST_IPSEC */
794
795 /* We are already being fwd'd from a firewall. */
796 if (next_hop != NULL)
797 goto pass;
798
799 /* No pfil hooks */
800 if (!pfil_has_hooks(&inet_pfil_hook)) {
801 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
802 /*
803 * Strip dummynet tags from stranded packets
804 */
805 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
806 KKASSERT(mtag != NULL);
807 m_tag_delete(m, mtag);
808 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED;
809 }
810 goto pass;
811 }
812
813 /*
814 * IpHack's section.
815 * - Xlate: translate packet's addr/port (NAT).
816 * - Firewall: deny/allow/etc.
817 * - Wrap: fake packet's addr/port <unimpl.>
818 * - Encapsulate: put it in another IP and send out. <unimp.>
819 */
820
821 /*
822 * Run through list of hooks for output packets.
823 */
824 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT);
825 if (error != 0 || m == NULL)
826 goto done;
827 ip = mtod(m, struct ip *);
828
829 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
830 /*
831 * Check dst to make sure it is directly reachable on the
832 * interface we previously thought it was.
833 * If it isn't (which may be likely in some situations) we have
834 * to re-route it (ie, find a route for the next-hop and the
835 * associated interface) and set them here. This is nested
836 * forwarding which in most cases is undesirable, except where
837 * such control is nigh impossible. So we do it here.
838 * And I'm babbling.
839 */
840 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
841 KKASSERT(mtag != NULL);
842 next_hop = m_tag_data(mtag);
843
844 /*
845 * Try local forwarding first
846 */
847 if (ip_localforward(m, next_hop, hlen))
848 goto done;
849
850 /*
851 * Relocate the route based on next_hop.
852 * If the current route is inp's cache, keep it untouched.
853 */
854 if (ro == &iproute && ro->ro_rt != NULL) {
855 RTFREE(ro->ro_rt);
856 ro->ro_rt = NULL;
857 }
858 ro = &iproute;
859 bzero(ro, sizeof *ro);
860
861 /*
862 * Forwarding to broadcast address is not allowed.
863 * XXX Should we follow IP_ROUTETOIF?
864 */
865 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF);
866
867 /* We are doing forwarding now */
868 flags |= IP_FORWARDING;
869
870 goto reroute;
871 }
872
873 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
874 struct dn_pkt *dn_pkt;
875
876 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
877 KKASSERT(mtag != NULL);
878 dn_pkt = m_tag_data(mtag);
879
880 /*
881 * Under certain cases it is not possible to recalculate
882 * 'ro' and 'dst', let alone 'flags', so just save them in
883 * dummynet tag and avoid the possible wrong reculcalation
884 * when we come back to ip_output() again.
885 *
886 * All other parameters have been already used and so they
887 * are not needed anymore.
888 * XXX if the ifp is deleted while a pkt is in dummynet,
889 * we are in trouble! (TODO use ifnet_detach_event)
890 *
891 * We need to copy *ro because for ICMP pkts (and maybe
892 * others) the caller passed a pointer into the stack;
893 * dst might also be a pointer into *ro so it needs to
894 * be updated.
895 */
896 dn_pkt->ro = *ro;
897 if (ro->ro_rt)
898 ro->ro_rt->rt_refcnt++;
899 if (dst == (struct sockaddr_in *)&ro->ro_dst) {
900 /* 'dst' points into 'ro' */
901 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst);
902 }
903 dn_pkt->dn_dst = dst;
904 dn_pkt->flags = flags;
905
906 ip_dn_queue(m);
907 goto done;
908 }
909 pass:
910 /* 127/8 must not appear on wire - RFC1122. */
911 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
912 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
913 if (!(ifp->if_flags & IFF_LOOPBACK)) {
914 ipstat.ips_badaddr++;
915 error = EADDRNOTAVAIL;
916 goto bad;
917 }
918 }
919
920 m->m_pkthdr.csum_flags |= CSUM_IP;
921 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
922 if (sw_csum & CSUM_DELAY_DATA) {
923 in_delayed_cksum(m);
924 sw_csum &= ~CSUM_DELAY_DATA;
925 }
926 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
927
928 /*
929 * If small enough for interface, or the interface will take
930 * care of the fragmentation for us, can just send directly.
931 */
932 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) &&
933 !(ip->ip_off & IP_DF))) {
934 ip->ip_len = htons(ip->ip_len);
935 ip->ip_off = htons(ip->ip_off);
936 ip->ip_sum = 0;
937 if (sw_csum & CSUM_DELAY_IP) {
938 if (ip->ip_vhl == IP_VHL_BORING)
939 ip->ip_sum = in_cksum_hdr(ip);
940 else
941 ip->ip_sum = in_cksum(m, hlen);
942 }
943
944 /* Record statistics for this interface address. */
945 if (!(flags & IP_FORWARDING) && ia) {
946 ia->ia_ifa.if_opackets++;
947 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
948 }
949
950 #ifdef IPSEC
951 /* clean ipsec history once it goes out of the node */
952 ipsec_delaux(m);
953 #endif
954
955 #ifdef MBUF_STRESS_TEST
956 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) {
957 struct mbuf *m1, *m2;
958 int length, tmp;
959
960 tmp = length = m->m_pkthdr.len;
961
962 while ((length -= mbuf_frag_size) >= 1) {
963 m1 = m_split(m, length, MB_DONTWAIT);
964 if (m1 == NULL)
965 break;
966 m2 = m;
967 while (m2->m_next != NULL)
968 m2 = m2->m_next;
969 m2->m_next = m1;
970 }
971 m->m_pkthdr.len = tmp;
972 }
973 #endif
974
975 #ifdef MPLS
976 if (!mpls_output_process(m, ro->ro_rt))
977 goto done;
978 #endif
979 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
980 ro->ro_rt);
981 goto done;
982 }
983
984 if (ip->ip_off & IP_DF) {
985 error = EMSGSIZE;
986 /*
987 * This case can happen if the user changed the MTU
988 * of an interface after enabling IP on it. Because
989 * most netifs don't keep track of routes pointing to
990 * them, there is no way for one to update all its
991 * routes when the MTU is changed.
992 */
993 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) &&
994 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) &&
995 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) {
996 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
997 }
998 ipstat.ips_cantfrag++;
999 goto bad;
1000 }
1001
1002 /*
1003 * Too large for interface; fragment if possible. If successful,
1004 * on return, m will point to a list of packets to be sent.
1005 */
1006 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum);
1007 if (error)
1008 goto bad;
1009 for (; m; m = m0) {
1010 m0 = m->m_nextpkt;
1011 m->m_nextpkt = NULL;
1012 #ifdef IPSEC
1013 /* clean ipsec history once it goes out of the node */
1014 ipsec_delaux(m);
1015 #endif
1016 if (error == 0) {
1017 /* Record statistics for this interface address. */
1018 if (ia != NULL) {
1019 ia->ia_ifa.if_opackets++;
1020 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1021 }
1022 #ifdef MPLS
1023 if (!mpls_output_process(m, ro->ro_rt))
1024 continue;
1025 #endif
1026 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
1027 ro->ro_rt);
1028 } else {
1029 m_freem(m);
1030 }
1031 }
1032
1033 if (error == 0)
1034 ipstat.ips_fragmented++;
1035
1036 done:
1037 if (ro == &iproute && ro->ro_rt != NULL) {
1038 RTFREE(ro->ro_rt);
1039 ro->ro_rt = NULL;
1040 }
1041 #ifdef IPSEC
1042 if (sp != NULL) {
1043 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1044 kprintf("DP ip_output call free SP:%p\n", sp));
1045 key_freesp(sp);
1046 }
1047 #endif
1048 #ifdef FAST_IPSEC
1049 if (sp != NULL)
1050 KEY_FREESP(&sp);
1051 #endif
1052 return (error);
1053 bad:
1054 m_freem(m);
1055 goto done;
1056 }
1057
1058 /*
1059 * Create a chain of fragments which fit the given mtu. m_frag points to the
1060 * mbuf to be fragmented; on return it points to the chain with the fragments.
1061 * Return 0 if no error. If error, m_frag may contain a partially built
1062 * chain of fragments that should be freed by the caller.
1063 *
1064 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
1065 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
1066 */
1067 int
1068 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
1069 u_long if_hwassist_flags, int sw_csum)
1070 {
1071 int error = 0;
1072 int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
1073 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
1074 int off;
1075 struct mbuf *m0 = *m_frag; /* the original packet */
1076 int firstlen;
1077 struct mbuf **mnext;
1078 int nfrags;
1079
1080 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */
1081 ipstat.ips_cantfrag++;
1082 return EMSGSIZE;
1083 }
1084
1085 /*
1086 * Must be able to put at least 8 bytes per fragment.
1087 */
1088 if (len < 8)
1089 return EMSGSIZE;
1090
1091 /*
1092 * If the interface will not calculate checksums on
1093 * fragmented packets, then do it here.
1094 */
1095 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) &&
1096 !(if_hwassist_flags & CSUM_IP_FRAGS)) {
1097 in_delayed_cksum(m0);
1098 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1099 }
1100
1101 if (len > PAGE_SIZE) {
1102 /*
1103 * Fragment large datagrams such that each segment
1104 * contains a multiple of PAGE_SIZE amount of data,
1105 * plus headers. This enables a receiver to perform
1106 * page-flipping zero-copy optimizations.
1107 *
1108 * XXX When does this help given that sender and receiver
1109 * could have different page sizes, and also mtu could
1110 * be less than the receiver's page size ?
1111 */
1112 int newlen;
1113 struct mbuf *m;
1114
1115 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next)
1116 off += m->m_len;
1117
1118 /*
1119 * firstlen (off - hlen) must be aligned on an
1120 * 8-byte boundary
1121 */
1122 if (off < hlen)
1123 goto smart_frag_failure;
1124 off = ((off - hlen) & ~7) + hlen;
1125 newlen = (~PAGE_MASK) & mtu;
1126 if ((newlen + sizeof(struct ip)) > mtu) {
1127 /* we failed, go back the default */
1128 smart_frag_failure:
1129 newlen = len;
1130 off = hlen + len;
1131 }
1132 len = newlen;
1133
1134 } else {
1135 off = hlen + len;
1136 }
1137
1138 firstlen = off - hlen;
1139 mnext = &m0->m_nextpkt; /* pointer to next packet */
1140
1141 /*
1142 * Loop through length of segment after first fragment,
1143 * make new header and copy data of each part and link onto chain.
1144 * Here, m0 is the original packet, m is the fragment being created.
1145 * The fragments are linked off the m_nextpkt of the original
1146 * packet, which after processing serves as the first fragment.
1147 */
1148 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) {
1149 struct ip *mhip; /* ip header on the fragment */
1150 struct mbuf *m;
1151 int mhlen = sizeof(struct ip);
1152
1153 MGETHDR(m, MB_DONTWAIT, MT_HEADER);
1154 if (m == NULL) {
1155 error = ENOBUFS;
1156 ipstat.ips_odropped++;
1157 goto done;
1158 }
1159 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
1160 /*
1161 * In the first mbuf, leave room for the link header, then
1162 * copy the original IP header including options. The payload
1163 * goes into an additional mbuf chain returned by m_copy().
1164 */
1165 m->m_data += max_linkhdr;
1166 mhip = mtod(m, struct ip *);
1167 *mhip = *ip;
1168 if (hlen > sizeof(struct ip)) {
1169 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip);
1170 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2);
1171 }
1172 m->m_len = mhlen;
1173 /* XXX do we need to add ip->ip_off below ? */
1174 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
1175 if (off + len >= ip->ip_len) { /* last fragment */
1176 len = ip->ip_len - off;
1177 m->m_flags |= M_LASTFRAG;
1178 } else
1179 mhip->ip_off |= IP_MF;
1180 mhip->ip_len = htons((u_short)(len + mhlen));
1181 m->m_next = m_copy(m0, off, len);
1182 if (m->m_next == NULL) { /* copy failed */
1183 m_free(m);
1184 error = ENOBUFS; /* ??? */
1185 ipstat.ips_odropped++;
1186 goto done;
1187 }
1188 m->m_pkthdr.len = mhlen + len;
1189 m->m_pkthdr.rcvif = NULL;
1190 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
1191 mhip->ip_off = htons(mhip->ip_off);
1192 mhip->ip_sum = 0;
1193 if (sw_csum & CSUM_DELAY_IP)
1194 mhip->ip_sum = in_cksum(m, mhlen);
1195 *mnext = m;
1196 mnext = &m->m_nextpkt;
1197 }
1198 ipstat.ips_ofragments += nfrags;
1199
1200 /* set first marker for fragment chain */
1201 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1202 m0->m_pkthdr.csum_data = nfrags;
1203
1204 /*
1205 * Update first fragment by trimming what's been copied out
1206 * and updating header.
1207 */
1208 m_adj(m0, hlen + firstlen - ip->ip_len);
1209 m0->m_pkthdr.len = hlen + firstlen;
1210 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1211 ip->ip_off |= IP_MF;
1212 ip->ip_off = htons(ip->ip_off);
1213 ip->ip_sum = 0;
1214 if (sw_csum & CSUM_DELAY_IP)
1215 ip->ip_sum = in_cksum(m0, hlen);
1216
1217 done:
1218 *m_frag = m0;
1219 return error;
1220 }
1221
1222 void
1223 in_delayed_cksum(struct mbuf *m)
1224 {
1225 struct ip *ip;
1226 u_short csum, offset;
1227
1228 ip = mtod(m, struct ip *);
1229 offset = IP_VHL_HL(ip->ip_vhl) << 2 ;
1230 csum = in_cksum_skip(m, ip->ip_len, offset);
1231 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
1232 csum = 0xffff;
1233 offset += m->m_pkthdr.csum_data; /* checksum offset */
1234
1235 if (offset + sizeof(u_short) > m->m_len) {
1236 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n",
1237 m->m_len, offset, ip->ip_p);
1238 /*
1239 * XXX
1240 * this shouldn't happen, but if it does, the
1241 * correct behavior may be to insert the checksum
1242 * in the existing chain instead of rearranging it.
1243 */
1244 m = m_pullup(m, offset + sizeof(u_short));
1245 }
1246 *(u_short *)(m->m_data + offset) = csum;
1247 }
1248
1249 /*
1250 * Insert IP options into preformed packet.
1251 * Adjust IP destination as required for IP source routing,
1252 * as indicated by a non-zero in_addr at the start of the options.
1253 *
1254 * XXX This routine assumes that the packet has no options in place.
1255 */
1256 static struct mbuf *
1257 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen)
1258 {
1259 struct ipoption *p = mtod(opt, struct ipoption *);
1260 struct mbuf *n;
1261 struct ip *ip = mtod(m, struct ip *);
1262 unsigned optlen;
1263
1264 optlen = opt->m_len - sizeof p->ipopt_dst;
1265 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) {
1266 *phlen = 0;
1267 return (m); /* XXX should fail */
1268 }
1269 if (p->ipopt_dst.s_addr)
1270 ip->ip_dst = p->ipopt_dst;
1271 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
1272 MGETHDR(n, MB_DONTWAIT, MT_HEADER);
1273 if (n == NULL) {
1274 *phlen = 0;
1275 return (m);
1276 }
1277 n->m_pkthdr.rcvif = NULL;
1278 n->m_pkthdr.len = m->m_pkthdr.len + optlen;
1279 m->m_len -= sizeof(struct ip);
1280 m->m_data += sizeof(struct ip);
1281 n->m_next = m;
1282 m = n;
1283 m->m_len = optlen + sizeof(struct ip);
1284 m->m_data += max_linkhdr;
1285 memcpy(mtod(m, void *), ip, sizeof(struct ip));
1286 } else {
1287 m->m_data -= optlen;
1288 m->m_len += optlen;
1289 m->m_pkthdr.len += optlen;
1290 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip));
1291 }
1292 ip = mtod(m, struct ip *);
1293 bcopy(p->ipopt_list, ip + 1, optlen);
1294 *phlen = sizeof(struct ip) + optlen;
1295 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2);
1296 ip->ip_len += optlen;
1297 return (m);
1298 }
1299
1300 /*
1301 * Copy options from ip to jp,
1302 * omitting those not copied during fragmentation.
1303 */
1304 int
1305 ip_optcopy(struct ip *ip, struct ip *jp)
1306 {
1307 u_char *cp, *dp;
1308 int opt, optlen, cnt;
1309
1310 cp = (u_char *)(ip + 1);
1311 dp = (u_char *)(jp + 1);
1312 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
1313 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1314 opt = cp[0];
1315 if (opt == IPOPT_EOL)
1316 break;
1317 if (opt == IPOPT_NOP) {
1318 /* Preserve for IP mcast tunnel's LSRR alignment. */
1319 *dp++ = IPOPT_NOP;
1320 optlen = 1;
1321 continue;
1322 }
1323
1324 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp,
1325 ("ip_optcopy: malformed ipv4 option"));
1326 optlen = cp[IPOPT_OLEN];
1327 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt,
1328 ("ip_optcopy: malformed ipv4 option"));
1329
1330 /* bogus lengths should have been caught by ip_dooptions */
1331 if (optlen > cnt)
1332 optlen = cnt;
1333 if (IPOPT_COPIED(opt)) {
1334 bcopy(cp, dp, optlen);
1335 dp += optlen;
1336 }
1337 }
1338 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
1339 *dp++ = IPOPT_EOL;
1340 return (optlen);
1341 }
1342
1343 /*
1344 * IP socket option processing.
1345 */
1346 int
1347 ip_ctloutput(struct socket *so, struct sockopt *sopt)
1348 {
1349 struct inpcb *inp = so->so_pcb;
1350 int error, optval;
1351
1352 error = optval = 0;
1353 if (sopt->sopt_level != IPPROTO_IP) {
1354 return (EINVAL);
1355 }
1356
1357 switch (sopt->sopt_dir) {
1358 case SOPT_SET:
1359 switch (sopt->sopt_name) {
1360 case IP_OPTIONS:
1361 #ifdef notyet
1362 case IP_RETOPTS:
1363 #endif
1364 {
1365 struct mbuf *m;
1366 if (sopt->sopt_valsize > MLEN) {
1367 error = EMSGSIZE;
1368 break;
1369 }
1370 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER);
1371 if (m == NULL) {
1372 error = ENOBUFS;
1373 break;
1374 }
1375 m->m_len = sopt->sopt_valsize;
1376 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len,
1377 m->m_len);
1378 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options,
1379 m));
1380 }
1381
1382 case IP_TOS:
1383 case IP_TTL:
1384 case IP_MINTTL:
1385 case IP_RECVOPTS:
1386 case IP_RECVRETOPTS:
1387 case IP_RECVDSTADDR:
1388 case IP_RECVIF:
1389 case IP_RECVTTL:
1390 case IP_FAITH:
1391 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1392 sizeof optval);
1393 if (error)
1394 break;
1395 switch (sopt->sopt_name) {
1396 case IP_TOS:
1397 inp->inp_ip_tos = optval;
1398 break;
1399
1400 case IP_TTL:
1401 inp->inp_ip_ttl = optval;
1402 break;
1403 case IP_MINTTL:
1404 if (optval >= 0 && optval <= MAXTTL)
1405 inp->inp_ip_minttl = optval;
1406 else
1407 error = EINVAL;
1408 break;
1409 #define OPTSET(bit) \
1410 if (optval) \
1411 inp->inp_flags |= bit; \
1412 else \
1413 inp->inp_flags &= ~bit;
1414
1415 case IP_RECVOPTS:
1416 OPTSET(INP_RECVOPTS);
1417 break;
1418
1419 case IP_RECVRETOPTS:
1420 OPTSET(INP_RECVRETOPTS);
1421 break;
1422
1423 case IP_RECVDSTADDR:
1424 OPTSET(INP_RECVDSTADDR);
1425 break;
1426
1427 case IP_RECVIF:
1428 OPTSET(INP_RECVIF);
1429 break;
1430
1431 case IP_RECVTTL:
1432 OPTSET(INP_RECVTTL);
1433 break;
1434
1435 case IP_FAITH:
1436 OPTSET(INP_FAITH);
1437 break;
1438 }
1439 break;
1440 #undef OPTSET
1441
1442 case IP_MULTICAST_IF:
1443 case IP_MULTICAST_VIF:
1444 case IP_MULTICAST_TTL:
1445 case IP_MULTICAST_LOOP:
1446 case IP_ADD_MEMBERSHIP:
1447 case IP_DROP_MEMBERSHIP:
1448 error = ip_setmoptions(sopt, &inp->inp_moptions);
1449 break;
1450
1451 case IP_PORTRANGE:
1452 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1453 sizeof optval);
1454 if (error)
1455 break;
1456
1457 switch (optval) {
1458 case IP_PORTRANGE_DEFAULT:
1459 inp->inp_flags &= ~(INP_LOWPORT);
1460 inp->inp_flags &= ~(INP_HIGHPORT);
1461 break;
1462
1463 case IP_PORTRANGE_HIGH:
1464 inp->inp_flags &= ~(INP_LOWPORT);
1465 inp->inp_flags |= INP_HIGHPORT;
1466 break;
1467
1468 case IP_PORTRANGE_LOW:
1469 inp->inp_flags &= ~(INP_HIGHPORT);
1470 inp->inp_flags |= INP_LOWPORT;
1471 break;
1472
1473 default:
1474 error = EINVAL;
1475 break;
1476 }
1477 break;
1478
1479 #if defined(IPSEC) || defined(FAST_IPSEC)
1480 case IP_IPSEC_POLICY:
1481 {
1482 caddr_t req;
1483 size_t len = 0;
1484 int priv;
1485 struct mbuf *m;
1486 int optname;
1487
1488 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1489 break;
1490 soopt_to_mbuf(sopt, m);
1491 priv = (sopt->sopt_td != NULL &&
1492 priv_check(sopt->sopt_td, PRIV_ROOT) != 0) ? 0 : 1;
1493 req = mtod(m, caddr_t);
1494 len = m->m_len;
1495 optname = sopt->sopt_name;
1496 error = ipsec4_set_policy(inp, optname, req, len, priv);
1497 m_freem(m);
1498 break;
1499 }
1500 #endif /*IPSEC*/
1501
1502 default:
1503 error = ENOPROTOOPT;
1504 break;
1505 }
1506 break;
1507
1508 case SOPT_GET:
1509 switch (sopt->sopt_name) {
1510 case IP_OPTIONS:
1511 case IP_RETOPTS:
1512 if (inp->inp_options)
1513 soopt_from_kbuf(sopt, mtod(inp->inp_options,
1514 char *),
1515 inp->inp_options->m_len);
1516 else
1517 sopt->sopt_valsize = 0;
1518 break;
1519
1520 case IP_TOS:
1521 case IP_TTL:
1522 case IP_MINTTL:
1523 case IP_RECVOPTS:
1524 case IP_RECVRETOPTS:
1525 case IP_RECVDSTADDR:
1526 case IP_RECVTTL:
1527 case IP_RECVIF:
1528 case IP_PORTRANGE:
1529 case IP_FAITH:
1530 switch (sopt->sopt_name) {
1531
1532 case IP_TOS:
1533 optval = inp->inp_ip_tos;
1534 break;
1535
1536 case IP_TTL:
1537 optval = inp->inp_ip_ttl;
1538 break;
1539 case IP_MINTTL:
1540 optval = inp->inp_ip_minttl;
1541 break;
1542
1543 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1544
1545 case IP_RECVOPTS:
1546 optval = OPTBIT(INP_RECVOPTS);
1547 break;
1548
1549 case IP_RECVRETOPTS:
1550 optval = OPTBIT(INP_RECVRETOPTS);
1551 break;
1552
1553 case IP_RECVDSTADDR:
1554 optval = OPTBIT(INP_RECVDSTADDR);
1555 break;
1556
1557 case IP_RECVTTL:
1558 optval = OPTBIT(INP_RECVTTL);
1559 break;
1560
1561 case IP_RECVIF:
1562 optval = OPTBIT(INP_RECVIF);
1563 break;
1564
1565 case IP_PORTRANGE:
1566 if (inp->inp_flags & INP_HIGHPORT)
1567 optval = IP_PORTRANGE_HIGH;
1568 else if (inp->inp_flags & INP_LOWPORT)
1569 optval = IP_PORTRANGE_LOW;
1570 else
1571 optval = 0;
1572 break;
1573
1574 case IP_FAITH:
1575 optval = OPTBIT(INP_FAITH);
1576 break;
1577 }
1578 soopt_from_kbuf(sopt, &optval, sizeof optval);
1579 break;
1580
1581 case IP_MULTICAST_IF:
1582 case IP_MULTICAST_VIF:
1583 case IP_MULTICAST_TTL:
1584 case IP_MULTICAST_LOOP:
1585 case IP_ADD_MEMBERSHIP:
1586 case IP_DROP_MEMBERSHIP:
1587 error = ip_getmoptions(sopt, inp->inp_moptions);
1588 break;
1589
1590 #if defined(IPSEC) || defined(FAST_IPSEC)
1591 case IP_IPSEC_POLICY:
1592 {
1593 struct mbuf *m = NULL;
1594 caddr_t req = NULL;
1595 size_t len = 0;
1596
1597 if (m != NULL) {
1598 req = mtod(m, caddr_t);
1599 len = m->m_len;
1600 }
1601 error = ipsec4_get_policy(so->so_pcb, req, len, &m);
1602 if (error == 0)
1603 error = soopt_from_mbuf(sopt, m); /* XXX */
1604 if (error == 0)
1605 m_freem(m);
1606 break;
1607 }
1608 #endif /*IPSEC*/
1609
1610 default:
1611 error = ENOPROTOOPT;
1612 break;
1613 }
1614 break;
1615 }
1616 return (error);
1617 }
1618
1619 /*
1620 * Set up IP options in pcb for insertion in output packets.
1621 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1622 * with destination address if source routed.
1623 */
1624 static int
1625 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m)
1626 {
1627 int cnt, optlen;
1628 u_char *cp;
1629 u_char opt;
1630
1631 /* turn off any old options */
1632 if (*pcbopt)
1633 m_free(*pcbopt);
1634 *pcbopt = 0;
1635 if (m == NULL || m->m_len == 0) {
1636 /*
1637 * Only turning off any previous options.
1638 */
1639 if (m != NULL)
1640 m_free(m);
1641 return (0);
1642 }
1643
1644 if (m->m_len % sizeof(int32_t))
1645 goto bad;
1646 /*
1647 * IP first-hop destination address will be stored before
1648 * actual options; move other options back
1649 * and clear it when none present.
1650 */
1651 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
1652 goto bad;
1653 cnt = m->m_len;
1654 m->m_len += sizeof(struct in_addr);
1655 cp = mtod(m, u_char *) + sizeof(struct in_addr);
1656 ovbcopy(mtod(m, caddr_t), cp, cnt);
1657 bzero(mtod(m, caddr_t), sizeof(struct in_addr));
1658
1659 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1660 opt = cp[IPOPT_OPTVAL];
1661 if (opt == IPOPT_EOL)
1662 break;
1663 if (opt == IPOPT_NOP)
1664 optlen = 1;
1665 else {
1666 if (cnt < IPOPT_OLEN + sizeof *cp)
1667 goto bad;
1668 optlen = cp[IPOPT_OLEN];
1669 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt)
1670 goto bad;
1671 }
1672 switch (opt) {
1673
1674 default:
1675 break;
1676
1677 case IPOPT_LSRR:
1678 case IPOPT_SSRR:
1679 /*
1680 * user process specifies route as:
1681 * ->A->B->C->D
1682 * D must be our final destination (but we can't
1683 * check that since we may not have connected yet).
1684 * A is first hop destination, which doesn't appear in
1685 * actual IP option, but is stored before the options.
1686 */
1687 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
1688 goto bad;
1689 m->m_len -= sizeof(struct in_addr);
1690 cnt -= sizeof(struct in_addr);
1691 optlen -= sizeof(struct in_addr);
1692 cp[IPOPT_OLEN] = optlen;
1693 /*
1694 * Move first hop before start of options.
1695 */
1696 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
1697 sizeof(struct in_addr));
1698 /*
1699 * Then copy rest of options back
1700 * to close up the deleted entry.
1701 */
1702 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr),
1703 &cp[IPOPT_OFFSET+1],
1704 cnt - (IPOPT_MINOFF - 1));
1705 break;
1706 }
1707 }
1708 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
1709 goto bad;
1710 *pcbopt = m;
1711 return (0);
1712
1713 bad:
1714 m_free(m);
1715 return (EINVAL);
1716 }
1717
1718 /*
1719 * XXX
1720 * The whole multicast option thing needs to be re-thought.
1721 * Several of these options are equally applicable to non-multicast
1722 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1723 * standard option (IP_TTL).
1724 */
1725
1726 /*
1727 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1728 */
1729 static struct ifnet *
1730 ip_multicast_if(struct in_addr *a, int *ifindexp)
1731 {
1732 int ifindex;
1733 struct ifnet *ifp;
1734
1735 if (ifindexp)
1736 *ifindexp = 0;
1737 if (ntohl(a->s_addr) >> 24 == 0) {
1738 ifindex = ntohl(a->s_addr) & 0xffffff;
1739 if (ifindex < 0 || if_index < ifindex)
1740 return NULL;
1741 ifp = ifindex2ifnet[ifindex];
1742 if (ifindexp)
1743 *ifindexp = ifindex;
1744 } else {
1745 ifp = INADDR_TO_IFP(a);
1746 }
1747 return ifp;
1748 }
1749
1750 /*
1751 * Set the IP multicast options in response to user setsockopt().
1752 */
1753 static int
1754 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop)
1755 {
1756 int error = 0;
1757 int i;
1758 struct in_addr addr;
1759 struct ip_mreq mreq;
1760 struct ifnet *ifp;
1761 struct ip_moptions *imo = *imop;
1762 int ifindex;
1763
1764 if (imo == NULL) {
1765 /*
1766 * No multicast option buffer attached to the pcb;
1767 * allocate one and initialize to default values.
1768 */
1769 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK);
1770
1771 *imop = imo;
1772 imo->imo_multicast_ifp = NULL;
1773 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1774 imo->imo_multicast_vif = -1;
1775 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1776 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
1777 imo->imo_num_memberships = 0;
1778 }
1779 switch (sopt->sopt_name) {
1780 /* store an index number for the vif you wanna use in the send */
1781 case IP_MULTICAST_VIF:
1782 if (legal_vif_num == 0) {
1783 error = EOPNOTSUPP;
1784 break;
1785 }
1786 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i);
1787 if (error)
1788 break;
1789 if (!legal_vif_num(i) && (i != -1)) {
1790 error = EINVAL;
1791 break;
1792 }
1793 imo->imo_multicast_vif = i;
1794 break;
1795
1796 case IP_MULTICAST_IF:
1797 /*
1798 * Select the interface for outgoing multicast packets.
1799 */
1800 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr);
1801 if (error)
1802 break;
1803
1804 /*
1805 * INADDR_ANY is used to remove a previous selection.
1806 * When no interface is selected, a default one is
1807 * chosen every time a multicast packet is sent.
1808 */
1809 if (addr.s_addr == INADDR_ANY) {
1810 imo->imo_multicast_ifp = NULL;
1811 break;
1812 }
1813 /*
1814 * The selected interface is identified by its local
1815 * IP address. Find the interface and confirm that
1816 * it supports multicasting.
1817 */
1818 crit_enter();
1819 ifp = ip_multicast_if(&addr, &ifindex);
1820 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1821 crit_exit();
1822 error = EADDRNOTAVAIL;
1823 break;
1824 }
1825 imo->imo_multicast_ifp = ifp;
1826 if (ifindex)
1827 imo->imo_multicast_addr = addr;
1828 else
1829 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1830 crit_exit();
1831 break;
1832
1833 case IP_MULTICAST_TTL:
1834 /*
1835 * Set the IP time-to-live for outgoing multicast packets.
1836 * The original multicast API required a char argument,
1837 * which is inconsistent with the rest of the socket API.
1838 * We allow either a char or an int.
1839 */
1840 if (sopt->sopt_valsize == 1) {
1841 u_char ttl;
1842 error = soopt_to_kbuf(sopt, &ttl, 1, 1);
1843 if (error)
1844 break;
1845 imo->imo_multicast_ttl = ttl;
1846 } else {
1847 u_int ttl;
1848 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl);
1849 if (error)
1850 break;
1851 if (ttl > 255)
1852 error = EINVAL;
1853 else
1854 imo->imo_multicast_ttl = ttl;
1855 }
1856 break;
1857
1858 case IP_MULTICAST_LOOP:
1859 /*
1860 * Set the loopback flag for outgoing multicast packets.
1861 * Must be zero or one. The original multicast API required a
1862 * char argument, which is inconsistent with the rest
1863 * of the socket API. We allow either a char or an int.
1864 */
1865 if (sopt->sopt_valsize == 1) {
1866 u_char loop;
1867
1868 error = soopt_to_kbuf(sopt, &loop, 1, 1);
1869 if (error)
1870 break;
1871 imo->imo_multicast_loop = !!loop;
1872 } else {
1873 u_int loop;
1874
1875 error = soopt_to_kbuf(sopt, &loop, sizeof loop,
1876 sizeof loop);
1877 if (error)
1878 break;
1879 imo->imo_multicast_loop = !!loop;
1880 }
1881 break;
1882
1883 case IP_ADD_MEMBERSHIP:
1884 /*
1885 * Add a multicast group membership.
1886 * Group must be a valid IP multicast address.
1887 */
1888 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1889 if (error)
1890 break;
1891
1892 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1893 error = EINVAL;
1894 break;
1895 }
1896 crit_enter();
1897 /*
1898 * If no interface address was provided, use the interface of
1899 * the route to the given multicast address.
1900 */
1901 if (mreq.imr_interface.s_addr == INADDR_ANY) {
1902 struct sockaddr_in dst;
1903 struct rtentry *rt;
1904
1905 bzero(&dst, sizeof(struct sockaddr_in));
1906 dst.sin_len = sizeof(struct sockaddr_in);
1907 dst.sin_family = AF_INET;
1908 dst.sin_addr = mreq.imr_multiaddr;
1909 rt = rtlookup((struct sockaddr *)&dst);
1910 if (rt == NULL) {
1911 error = EADDRNOTAVAIL;
1912 crit_exit();
1913 break;
1914 }
1915 --rt->rt_refcnt;
1916 ifp = rt->rt_ifp;
1917 } else {
1918 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1919 }
1920
1921 /*
1922 * See if we found an interface, and confirm that it
1923 * supports multicast.
1924 */
1925 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1926 error = EADDRNOTAVAIL;
1927 crit_exit();
1928 break;
1929 }
1930 /*
1931 * See if the membership already exists or if all the
1932 * membership slots are full.
1933 */
1934 for (i = 0; i < imo->imo_num_memberships; ++i) {
1935 if (imo->imo_membership[i]->inm_ifp == ifp &&
1936 imo->imo_membership[i]->inm_addr.s_addr
1937 == mreq.imr_multiaddr.s_addr)
1938 break;
1939 }
1940 if (i < imo->imo_num_memberships) {
1941 error = EADDRINUSE;
1942 crit_exit();
1943 break;
1944 }
1945 if (i == IP_MAX_MEMBERSHIPS) {
1946 error = ETOOMANYREFS;
1947 crit_exit();
1948 break;
1949 }
1950 /*
1951 * Everything looks good; add a new record to the multicast
1952 * address list for the given interface.
1953 */
1954 if ((imo->imo_membership[i] =
1955 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) {
1956 error = ENOBUFS;
1957 crit_exit();
1958 break;
1959 }
1960 ++imo->imo_num_memberships;
1961 crit_exit();
1962 break;
1963
1964 case IP_DROP_MEMBERSHIP:
1965 /*
1966 * Drop a multicast group membership.
1967 * Group must be a valid IP multicast address.
1968 */
1969 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1970 if (error)
1971 break;
1972
1973 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1974 error = EINVAL;
1975 break;
1976 }
1977
1978 crit_enter();
1979 /*
1980 * If an interface address was specified, get a pointer
1981 * to its ifnet structure.
1982 */
1983 if (mreq.imr_interface.s_addr == INADDR_ANY)
1984 ifp = NULL;
1985 else {
1986 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1987 if (ifp == NULL) {
1988 error = EADDRNOTAVAIL;
1989 crit_exit();
1990 break;
1991 }
1992 }
1993 /*
1994 * Find the membership in the membership array.
1995 */
1996 for (i = 0; i < imo->imo_num_memberships; ++i) {
1997 if ((ifp == NULL ||
1998 imo->imo_membership[i]->inm_ifp == ifp) &&
1999 imo->imo_membership[i]->inm_addr.s_addr ==
2000 mreq.imr_multiaddr.s_addr)
2001 break;
2002 }
2003 if (i == imo->imo_num_memberships) {
2004 error = EADDRNOTAVAIL;
2005 crit_exit();
2006 break;
2007 }
2008 /*
2009 * Give up the multicast address record to which the
2010 * membership points.
2011 */
2012 in_delmulti(imo->imo_membership[i]);
2013 /*
2014 * Remove the gap in the membership array.
2015 */
2016 for (++i; i < imo->imo_num_memberships; ++i)
2017 imo->imo_membership[i-1] = imo->imo_membership[i];
2018 --imo->imo_num_memberships;
2019 crit_exit();
2020 break;
2021
2022 default:
2023 error = EOPNOTSUPP;
2024 break;
2025 }
2026
2027 /*
2028 * If all options have default values, no need to keep the mbuf.
2029 */
2030 if (imo->imo_multicast_ifp == NULL &&
2031 imo->imo_multicast_vif == -1 &&
2032 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
2033 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
2034 imo->imo_num_memberships == 0) {
2035 kfree(*imop, M_IPMOPTS);
2036 *imop = NULL;
2037 }
2038
2039 return (error);
2040 }
2041
2042 /*
2043 * Return the IP multicast options in response to user getsockopt().
2044 */
2045 static int
2046 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo)
2047 {
2048 struct in_addr addr;
2049 struct in_ifaddr *ia;
2050 int error, optval;
2051 u_char coptval;
2052
2053 error = 0;
2054 switch (sopt->sopt_name) {
2055 case IP_MULTICAST_VIF:
2056 if (imo != NULL)
2057 optval = imo->imo_multicast_vif;
2058 else
2059 optval = -1;
2060 soopt_from_kbuf(sopt, &optval, sizeof optval);
2061 break;
2062
2063 case IP_MULTICAST_IF:
2064 if (imo == NULL || imo->imo_multicast_ifp == NULL)
2065 addr.s_addr = INADDR_ANY;
2066 else if (imo->imo_multicast_addr.s_addr) {
2067 /* return the value user has set */
2068 addr = imo->imo_multicast_addr;
2069 } else {
2070 ia = IFP_TO_IA(imo->imo_multicast_ifp);
2071 addr.s_addr = (ia == NULL) ? INADDR_ANY
2072 : IA_SIN(ia)->sin_addr.s_addr;
2073 }
2074 soopt_from_kbuf(sopt, &addr, sizeof addr);
2075 break;
2076
2077 case IP_MULTICAST_TTL:
2078 if (imo == NULL)
2079 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
2080 else
2081 optval = coptval = imo->imo_multicast_ttl;
2082 if (sopt->sopt_valsize == 1)
2083 soopt_from_kbuf(sopt, &coptval, 1);
2084 else
2085 soopt_from_kbuf(sopt, &optval, sizeof optval);
2086 break;
2087
2088 case IP_MULTICAST_LOOP:
2089 if (imo == NULL)
2090 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
2091 else
2092 optval = coptval = imo->imo_multicast_loop;
2093 if (sopt->sopt_valsize == 1)
2094 soopt_from_kbuf(sopt, &coptval, 1);
2095 else
2096 soopt_from_kbuf(sopt, &optval, sizeof optval);
2097 break;
2098
2099 default:
2100 error = ENOPROTOOPT;
2101 break;
2102 }
2103 return (error);
2104 }
2105
2106 /*
2107 * Discard the IP multicast options.
2108 */
2109 void
2110 ip_freemoptions(struct ip_moptions *imo)
2111 {
2112 int i;
2113
2114 if (imo != NULL) {
2115 for (i = 0; i < imo->imo_num_memberships; ++i)
2116 in_delmulti(imo->imo_membership[i]);
2117 kfree(imo, M_IPMOPTS);
2118 }
2119 }
2120
2121 /*
2122 * Routine called from ip_output() to loop back a copy of an IP multicast
2123 * packet to the input queue of a specified interface. Note that this
2124 * calls the output routine of the loopback "driver", but with an interface
2125 * pointer that might NOT be a loopback interface -- evil, but easier than
2126 * replicating that code here.
2127 */
2128 static void
2129 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst,
2130 int hlen)
2131 {
2132 struct ip *ip;
2133 struct mbuf *copym;
2134
2135 copym = m_copypacket(m, MB_DONTWAIT);
2136 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
2137 copym = m_pullup(copym, hlen);
2138 if (copym != NULL) {
2139 /*
2140 * if the checksum hasn't been computed, mark it as valid
2141 */
2142 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2143 in_delayed_cksum(copym);
2144 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
2145 copym->m_pkthdr.csum_flags |=
2146 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2147 copym->m_pkthdr.csum_data = 0xffff;
2148 }
2149 /*
2150 * We don't bother to fragment if the IP length is greater
2151 * than the interface's MTU. Can this possibly matter?
2152 */
2153 ip = mtod(copym, struct ip *);
2154 ip->ip_len = htons(ip->ip_len);
2155 ip->ip_off = htons(ip->ip_off);
2156 ip->ip_sum = 0;
2157 if (ip->ip_vhl == IP_VHL_BORING) {
2158 ip->ip_sum = in_cksum_hdr(ip);
2159 } else {
2160 ip->ip_sum = in_cksum(copym, hlen);
2161 }
2162 /*
2163 * NB:
2164 * It's not clear whether there are any lingering
2165 * reentrancy problems in other areas which might
2166 * be exposed by using ip_input directly (in
2167 * particular, everything which modifies the packet
2168 * in-place). Yet another option is using the
2169 * protosw directly to deliver the looped back
2170 * packet. For the moment, we'll err on the side
2171 * of safety by using if_simloop().
2172 */
2173 #if 1 /* XXX */
2174 if (dst->sin_family != AF_INET) {
2175 kprintf("ip_mloopback: bad address family %d\n",
2176 dst->sin_family);
2177 dst->sin_family = AF_INET;
2178 }
2179 #endif
2180 if_simloop(ifp, copym, dst->sin_family, 0);
2181 }
2182 }
DragonFly BSD