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. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
34 * $FreeBSD: releng/5.0/sys/netinet/ip_output.c 107112 2002-11-20 18:56:25Z luigi $
35 */
36
37 #include "opt_ipfw.h"
38 #include "opt_ipdn.h"
39 #include "opt_ipdivert.h"
40 #include "opt_ipfilter.h"
41 #include "opt_ipsec.h"
42 #include "opt_mac.h"
43 #include "opt_pfil_hooks.h"
44 #include "opt_random_ip_id.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
49 #include <sys/mac.h>
50 #include <sys/malloc.h>
51 #include <sys/mbuf.h>
52 #include <sys/protosw.h>
53 #include <sys/socket.h>
54 #include <sys/socketvar.h>
55
56 #include <net/if.h>
57 #include <net/route.h>
58
59 #include <netinet/in.h>
60 #include <netinet/in_systm.h>
61 #include <netinet/ip.h>
62 #include <netinet/in_pcb.h>
63 #include <netinet/in_var.h>
64 #include <netinet/ip_var.h>
65
66 #include <machine/in_cksum.h>
67
68 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options");
69
70 #ifdef IPSEC
71 #include <netinet6/ipsec.h>
72 #include <netkey/key.h>
73 #ifdef IPSEC_DEBUG
74 #include <netkey/key_debug.h>
75 #else
76 #define KEYDEBUG(lev,arg)
77 #endif
78 #endif /*IPSEC*/
79
80 #ifdef FAST_IPSEC
81 #include <netipsec/ipsec.h>
82 #include <netipsec/xform.h>
83 #include <netipsec/key.h>
84 #endif /*FAST_IPSEC*/
85
86 #include <netinet/ip_fw.h>
87 #include <netinet/ip_dummynet.h>
88
89 #define print_ip(x, a, y) printf("%s %d.%d.%d.%d%s",\
90 x, (ntohl(a.s_addr)>>24)&0xFF,\
91 (ntohl(a.s_addr)>>16)&0xFF,\
92 (ntohl(a.s_addr)>>8)&0xFF,\
93 (ntohl(a.s_addr))&0xFF, y);
94
95 u_short ip_id;
96
97 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *);
98 static struct ifnet *ip_multicast_if(struct in_addr *, int *);
99 static void ip_mloopback
100 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int);
101 static int ip_getmoptions
102 (struct sockopt *, struct ip_moptions *);
103 static int ip_pcbopts(int, struct mbuf **, struct mbuf *);
104 static int ip_setmoptions
105 (struct sockopt *, struct ip_moptions **);
106
107 int ip_optcopy(struct ip *, struct ip *);
108
109
110 extern struct protosw inetsw[];
111
112 /*
113 * IP output. The packet in mbuf chain m contains a skeletal IP
114 * header (with len, off, ttl, proto, tos, src, dst).
115 * The mbuf chain containing the packet will be freed.
116 * The mbuf opt, if present, will not be freed.
117 */
118 int
119 ip_output(m0, opt, ro, flags, imo, inp)
120 struct mbuf *m0;
121 struct mbuf *opt;
122 struct route *ro;
123 int flags;
124 struct ip_moptions *imo;
125 struct inpcb *inp;
126 {
127 struct ip *ip, *mhip;
128 struct ifnet *ifp = NULL; /* keep compiler happy */
129 struct mbuf *m;
130 int hlen = sizeof (struct ip);
131 int len, off, error = 0;
132 struct sockaddr_in *dst = NULL; /* keep compiler happy */
133 struct in_ifaddr *ia = NULL;
134 int isbroadcast, sw_csum;
135 struct in_addr pkt_dst;
136 #ifdef IPSEC
137 struct route iproute;
138 struct secpolicy *sp = NULL;
139 struct socket *so = inp ? inp->inp_socket : NULL;
140 #endif
141 #ifdef FAST_IPSEC
142 struct route iproute;
143 struct m_tag *mtag;
144 struct secpolicy *sp = NULL;
145 struct tdb_ident *tdbi;
146 int s;
147 #endif /* FAST_IPSEC */
148 struct ip_fw_args args;
149 int src_was_INADDR_ANY = 0; /* as the name says... */
150 #ifdef PFIL_HOOKS
151 struct packet_filter_hook *pfh;
152 struct mbuf *m1;
153 int rv;
154 #endif /* PFIL_HOOKS */
155
156 args.eh = NULL;
157 args.rule = NULL;
158 args.next_hop = NULL;
159 args.divert_rule = 0; /* divert cookie */
160
161 /* Grab info from MT_TAG mbufs prepended to the chain. */
162 for (; m0 && m0->m_type == MT_TAG; m0 = m0->m_next) {
163 switch(m0->_m_tag_id) {
164 default:
165 printf("ip_output: unrecognised MT_TAG tag %d\n",
166 m0->_m_tag_id);
167 break;
168
169 case PACKET_TAG_DUMMYNET:
170 /*
171 * the packet was already tagged, so part of the
172 * processing was already done, and we need to go down.
173 * Get parameters from the header.
174 */
175 args.rule = ((struct dn_pkt *)m0)->rule;
176 opt = NULL ;
177 ro = & ( ((struct dn_pkt *)m0)->ro ) ;
178 imo = NULL ;
179 dst = ((struct dn_pkt *)m0)->dn_dst ;
180 ifp = ((struct dn_pkt *)m0)->ifp ;
181 flags = ((struct dn_pkt *)m0)->flags ;
182 break;
183
184 case PACKET_TAG_DIVERT:
185 args.divert_rule = (intptr_t)m0->m_data & 0xffff;
186 break;
187
188 case PACKET_TAG_IPFORWARD:
189 args.next_hop = (struct sockaddr_in *)m0->m_data;
190 break;
191 }
192 }
193 m = m0;
194
195 KASSERT(!m || (m->m_flags & M_PKTHDR) != 0, ("ip_output: no HDR"));
196 #ifndef FAST_IPSEC
197 KASSERT(ro != NULL, ("ip_output: no route, proto %d",
198 mtod(m, struct ip *)->ip_p));
199 #endif
200
201 if (args.rule != NULL) { /* dummynet already saw us */
202 ip = mtod(m, struct ip *);
203 hlen = ip->ip_hl << 2 ;
204 if (ro->ro_rt)
205 ia = ifatoia(ro->ro_rt->rt_ifa);
206 goto sendit;
207 }
208
209 if (opt) {
210 len = 0;
211 m = ip_insertoptions(m, opt, &len);
212 if (len != 0)
213 hlen = len;
214 }
215 ip = mtod(m, struct ip *);
216 pkt_dst = args.next_hop ? args.next_hop->sin_addr : ip->ip_dst;
217
218 /*
219 * Fill in IP header.
220 */
221 if ((flags & (IP_FORWARDING|IP_RAWOUTPUT)) == 0) {
222 ip->ip_v = IPVERSION;
223 ip->ip_hl = hlen >> 2;
224 ip->ip_off &= IP_DF;
225 #ifdef RANDOM_IP_ID
226 ip->ip_id = ip_randomid();
227 #else
228 ip->ip_id = htons(ip_id++);
229 #endif
230 ipstat.ips_localout++;
231 } else {
232 hlen = ip->ip_hl << 2;
233 }
234
235 #ifdef FAST_IPSEC
236 if (ro == NULL) {
237 ro = &iproute;
238 bzero(ro, sizeof (*ro));
239 }
240 #endif /* FAST_IPSEC */
241 dst = (struct sockaddr_in *)&ro->ro_dst;
242 /*
243 * If there is a cached route,
244 * check that it is to the same destination
245 * and is still up. If not, free it and try again.
246 * The address family should also be checked in case of sharing the
247 * cache with IPv6.
248 */
249 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 ||
250 dst->sin_family != AF_INET ||
251 dst->sin_addr.s_addr != pkt_dst.s_addr)) {
252 RTFREE(ro->ro_rt);
253 ro->ro_rt = (struct rtentry *)0;
254 }
255 if (ro->ro_rt == 0) {
256 bzero(dst, sizeof(*dst));
257 dst->sin_family = AF_INET;
258 dst->sin_len = sizeof(*dst);
259 dst->sin_addr = pkt_dst;
260 }
261 /*
262 * If routing to interface only,
263 * short circuit routing lookup.
264 */
265 if (flags & IP_ROUTETOIF) {
266 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == 0 &&
267 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == 0) {
268 ipstat.ips_noroute++;
269 error = ENETUNREACH;
270 goto bad;
271 }
272 ifp = ia->ia_ifp;
273 ip->ip_ttl = 1;
274 isbroadcast = in_broadcast(dst->sin_addr, ifp);
275 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
276 imo != NULL && imo->imo_multicast_ifp != NULL) {
277 /*
278 * Bypass the normal routing lookup for multicast
279 * packets if the interface is specified.
280 */
281 ifp = imo->imo_multicast_ifp;
282 IFP_TO_IA(ifp, ia);
283 isbroadcast = 0; /* fool gcc */
284 } else {
285 /*
286 * If this is the case, we probably don't want to allocate
287 * a protocol-cloned route since we didn't get one from the
288 * ULP. This lets TCP do its thing, while not burdening
289 * forwarding or ICMP with the overhead of cloning a route.
290 * Of course, we still want to do any cloning requested by
291 * the link layer, as this is probably required in all cases
292 * for correct operation (as it is for ARP).
293 */
294 if (ro->ro_rt == 0)
295 rtalloc_ign(ro, RTF_PRCLONING);
296 if (ro->ro_rt == 0) {
297 ipstat.ips_noroute++;
298 error = EHOSTUNREACH;
299 goto bad;
300 }
301 ia = ifatoia(ro->ro_rt->rt_ifa);
302 ifp = ro->ro_rt->rt_ifp;
303 ro->ro_rt->rt_use++;
304 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
305 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
306 if (ro->ro_rt->rt_flags & RTF_HOST)
307 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
308 else
309 isbroadcast = in_broadcast(dst->sin_addr, ifp);
310 }
311 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
312 struct in_multi *inm;
313
314 m->m_flags |= M_MCAST;
315 /*
316 * IP destination address is multicast. Make sure "dst"
317 * still points to the address in "ro". (It may have been
318 * changed to point to a gateway address, above.)
319 */
320 dst = (struct sockaddr_in *)&ro->ro_dst;
321 /*
322 * See if the caller provided any multicast options
323 */
324 if (imo != NULL) {
325 ip->ip_ttl = imo->imo_multicast_ttl;
326 if (imo->imo_multicast_vif != -1)
327 ip->ip_src.s_addr =
328 ip_mcast_src ?
329 ip_mcast_src(imo->imo_multicast_vif) :
330 INADDR_ANY;
331 } else
332 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
333 /*
334 * Confirm that the outgoing interface supports multicast.
335 */
336 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
337 if ((ifp->if_flags & IFF_MULTICAST) == 0) {
338 ipstat.ips_noroute++;
339 error = ENETUNREACH;
340 goto bad;
341 }
342 }
343 /*
344 * If source address not specified yet, use address
345 * of outgoing interface.
346 */
347 if (ip->ip_src.s_addr == INADDR_ANY) {
348 /* Interface may have no addresses. */
349 if (ia != NULL)
350 ip->ip_src = IA_SIN(ia)->sin_addr;
351 }
352
353 if (ip_mrouter && (flags & IP_FORWARDING) == 0) {
354 /*
355 * XXX
356 * delayed checksums are not currently
357 * compatible with IP multicast routing
358 */
359 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
360 in_delayed_cksum(m);
361 m->m_pkthdr.csum_flags &=
362 ~CSUM_DELAY_DATA;
363 }
364 }
365 IN_LOOKUP_MULTI(pkt_dst, ifp, inm);
366 if (inm != NULL &&
367 (imo == NULL || imo->imo_multicast_loop)) {
368 /*
369 * If we belong to the destination multicast group
370 * on the outgoing interface, and the caller did not
371 * forbid loopback, loop back a copy.
372 */
373 ip_mloopback(ifp, m, dst, hlen);
374 }
375 else {
376 /*
377 * If we are acting as a multicast router, perform
378 * multicast forwarding as if the packet had just
379 * arrived on the interface to which we are about
380 * to send. The multicast forwarding function
381 * recursively calls this function, using the
382 * IP_FORWARDING flag to prevent infinite recursion.
383 *
384 * Multicasts that are looped back by ip_mloopback(),
385 * above, will be forwarded by the ip_input() routine,
386 * if necessary.
387 */
388 if (ip_mrouter && (flags & IP_FORWARDING) == 0) {
389 /*
390 * If rsvp daemon is not running, do not
391 * set ip_moptions. This ensures that the packet
392 * is multicast and not just sent down one link
393 * as prescribed by rsvpd.
394 */
395 if (!rsvp_on)
396 imo = NULL;
397 if (ip_mforward &&
398 ip_mforward(ip, ifp, m, imo) != 0) {
399 m_freem(m);
400 goto done;
401 }
402 }
403 }
404
405 /*
406 * Multicasts with a time-to-live of zero may be looped-
407 * back, above, but must not be transmitted on a network.
408 * Also, multicasts addressed to the loopback interface
409 * are not sent -- the above call to ip_mloopback() will
410 * loop back a copy if this host actually belongs to the
411 * destination group on the loopback interface.
412 */
413 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
414 m_freem(m);
415 goto done;
416 }
417
418 goto sendit;
419 }
420 #ifndef notdef
421 /*
422 * If the source address is not specified yet, use the address
423 * of the outoing interface. In case, keep note we did that, so
424 * if the the firewall changes the next-hop causing the output
425 * interface to change, we can fix that.
426 */
427 if (ip->ip_src.s_addr == INADDR_ANY) {
428 /* Interface may have no addresses. */
429 if (ia != NULL) {
430 ip->ip_src = IA_SIN(ia)->sin_addr;
431 src_was_INADDR_ANY = 1;
432 }
433 }
434 #endif /* notdef */
435 /*
436 * Verify that we have any chance at all of being able to queue
437 * the packet or packet fragments
438 */
439 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >=
440 ifp->if_snd.ifq_maxlen) {
441 error = ENOBUFS;
442 ipstat.ips_odropped++;
443 goto bad;
444 }
445
446 /*
447 * Look for broadcast address and
448 * verify user is allowed to send
449 * such a packet.
450 */
451 if (isbroadcast) {
452 if ((ifp->if_flags & IFF_BROADCAST) == 0) {
453 error = EADDRNOTAVAIL;
454 goto bad;
455 }
456 if ((flags & IP_ALLOWBROADCAST) == 0) {
457 error = EACCES;
458 goto bad;
459 }
460 /* don't allow broadcast messages to be fragmented */
461 if ((u_short)ip->ip_len > ifp->if_mtu) {
462 error = EMSGSIZE;
463 goto bad;
464 }
465 m->m_flags |= M_BCAST;
466 } else {
467 m->m_flags &= ~M_BCAST;
468 }
469
470 sendit:
471 #ifdef IPSEC
472 /* get SP for this packet */
473 if (so == NULL)
474 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error);
475 else
476 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
477
478 if (sp == NULL) {
479 ipsecstat.out_inval++;
480 goto bad;
481 }
482
483 error = 0;
484
485 /* check policy */
486 switch (sp->policy) {
487 case IPSEC_POLICY_DISCARD:
488 /*
489 * This packet is just discarded.
490 */
491 ipsecstat.out_polvio++;
492 goto bad;
493
494 case IPSEC_POLICY_BYPASS:
495 case IPSEC_POLICY_NONE:
496 /* no need to do IPsec. */
497 goto skip_ipsec;
498
499 case IPSEC_POLICY_IPSEC:
500 if (sp->req == NULL) {
501 /* acquire a policy */
502 error = key_spdacquire(sp);
503 goto bad;
504 }
505 break;
506
507 case IPSEC_POLICY_ENTRUST:
508 default:
509 printf("ip_output: Invalid policy found. %d\n", sp->policy);
510 }
511 {
512 struct ipsec_output_state state;
513 bzero(&state, sizeof(state));
514 state.m = m;
515 if (flags & IP_ROUTETOIF) {
516 state.ro = &iproute;
517 bzero(&iproute, sizeof(iproute));
518 } else
519 state.ro = ro;
520 state.dst = (struct sockaddr *)dst;
521
522 ip->ip_sum = 0;
523
524 /*
525 * XXX
526 * delayed checksums are not currently compatible with IPsec
527 */
528 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
529 in_delayed_cksum(m);
530 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
531 }
532
533 ip->ip_len = htons(ip->ip_len);
534 ip->ip_off = htons(ip->ip_off);
535
536 error = ipsec4_output(&state, sp, flags);
537
538 m = state.m;
539 if (flags & IP_ROUTETOIF) {
540 /*
541 * if we have tunnel mode SA, we may need to ignore
542 * IP_ROUTETOIF.
543 */
544 if (state.ro != &iproute || state.ro->ro_rt != NULL) {
545 flags &= ~IP_ROUTETOIF;
546 ro = state.ro;
547 }
548 } else
549 ro = state.ro;
550 dst = (struct sockaddr_in *)state.dst;
551 if (error) {
552 /* mbuf is already reclaimed in ipsec4_output. */
553 m0 = NULL;
554 switch (error) {
555 case EHOSTUNREACH:
556 case ENETUNREACH:
557 case EMSGSIZE:
558 case ENOBUFS:
559 case ENOMEM:
560 break;
561 default:
562 printf("ip4_output (ipsec): error code %d\n", error);
563 /*fall through*/
564 case ENOENT:
565 /* don't show these error codes to the user */
566 error = 0;
567 break;
568 }
569 goto bad;
570 }
571 }
572
573 /* be sure to update variables that are affected by ipsec4_output() */
574 ip = mtod(m, struct ip *);
575 hlen = ip->ip_hl << 2;
576 if (ro->ro_rt == NULL) {
577 if ((flags & IP_ROUTETOIF) == 0) {
578 printf("ip_output: "
579 "can't update route after IPsec processing\n");
580 error = EHOSTUNREACH; /*XXX*/
581 goto bad;
582 }
583 } else {
584 ia = ifatoia(ro->ro_rt->rt_ifa);
585 ifp = ro->ro_rt->rt_ifp;
586 }
587
588 /* make it flipped, again. */
589 ip->ip_len = ntohs(ip->ip_len);
590 ip->ip_off = ntohs(ip->ip_off);
591 skip_ipsec:
592 #endif /*IPSEC*/
593 #ifdef FAST_IPSEC
594 /*
595 * Check the security policy (SP) for the packet and, if
596 * required, do IPsec-related processing. There are two
597 * cases here; the first time a packet is sent through
598 * it will be untagged and handled by ipsec4_checkpolicy.
599 * If the packet is resubmitted to ip_output (e.g. after
600 * AH, ESP, etc. processing), there will be a tag to bypass
601 * the lookup and related policy checking.
602 */
603 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
604 s = splnet();
605 if (mtag != NULL) {
606 tdbi = (struct tdb_ident *)(mtag + 1);
607 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
608 if (sp == NULL)
609 error = -EINVAL; /* force silent drop */
610 m_tag_delete(m, mtag);
611 } else {
612 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags,
613 &error, inp);
614 }
615 /*
616 * There are four return cases:
617 * sp != NULL apply IPsec policy
618 * sp == NULL, error == 0 no IPsec handling needed
619 * sp == NULL, error == -EINVAL discard packet w/o error
620 * sp == NULL, error != 0 discard packet, report error
621 */
622 if (sp != NULL) {
623 /* Loop detection, check if ipsec processing already done */
624 KASSERT(sp->req != NULL, ("ip_output: no ipsec request"));
625 for (mtag = m_tag_first(m); mtag != NULL;
626 mtag = m_tag_next(m, mtag)) {
627 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
628 continue;
629 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
630 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
631 continue;
632 /*
633 * Check if policy has an SA associated with it.
634 * This can happen when an SP has yet to acquire
635 * an SA; e.g. on first reference. If it occurs,
636 * then we let ipsec4_process_packet do its thing.
637 */
638 if (sp->req->sav == NULL)
639 break;
640 tdbi = (struct tdb_ident *)(mtag + 1);
641 if (tdbi->spi == sp->req->sav->spi &&
642 tdbi->proto == sp->req->sav->sah->saidx.proto &&
643 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst,
644 sizeof (union sockaddr_union)) == 0) {
645 /*
646 * No IPsec processing is needed, free
647 * reference to SP.
648 *
649 * NB: null pointer to avoid free at
650 * done: below.
651 */
652 KEY_FREESP(&sp), sp = NULL;
653 splx(s);
654 goto spd_done;
655 }
656 }
657
658 /*
659 * Do delayed checksums now because we send before
660 * this is done in the normal processing path.
661 */
662 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
663 in_delayed_cksum(m);
664 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
665 }
666
667 ip->ip_len = htons(ip->ip_len);
668 ip->ip_off = htons(ip->ip_off);
669
670 /* NB: callee frees mbuf */
671 error = ipsec4_process_packet(m, sp->req, flags, 0);
672 splx(s);
673 goto done;
674 } else {
675 splx(s);
676
677 if (error != 0) {
678 /*
679 * Hack: -EINVAL is used to signal that a packet
680 * should be silently discarded. This is typically
681 * because we asked key management for an SA and
682 * it was delayed (e.g. kicked up to IKE).
683 */
684 if (error == -EINVAL)
685 error = 0;
686 goto bad;
687 } else {
688 /* No IPsec processing for this packet. */
689 }
690 #ifdef notyet
691 /*
692 * If deferred crypto processing is needed, check that
693 * the interface supports it.
694 */
695 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL);
696 if (mtag != NULL && (ifp->if_capenable & IFCAP_IPSEC) == 0) {
697 /* notify IPsec to do its own crypto */
698 ipsp_skipcrypto_unmark((struct tdb_ident *)(mtag + 1));
699 error = EHOSTUNREACH;
700 goto bad;
701 }
702 #endif
703 }
704 spd_done:
705 #endif /* FAST_IPSEC */
706
707 /*
708 * IpHack's section.
709 * - Xlate: translate packet's addr/port (NAT).
710 * - Firewall: deny/allow/etc.
711 * - Wrap: fake packet's addr/port <unimpl.>
712 * - Encapsulate: put it in another IP and send out. <unimp.>
713 */
714 #ifdef PFIL_HOOKS
715 /*
716 * Run through list of hooks for output packets.
717 */
718 m1 = m;
719 pfh = pfil_hook_get(PFIL_OUT, &inetsw[ip_protox[IPPROTO_IP]].pr_pfh);
720 for (; pfh; pfh = TAILQ_NEXT(pfh, pfil_link))
721 if (pfh->pfil_func) {
722 rv = pfh->pfil_func(ip, hlen, ifp, 1, &m1);
723 if (rv) {
724 error = EHOSTUNREACH;
725 goto done;
726 }
727 m = m1;
728 if (m == NULL)
729 goto done;
730 ip = mtod(m, struct ip *);
731 }
732 #endif /* PFIL_HOOKS */
733
734 /*
735 * Check with the firewall...
736 * but not if we are already being fwd'd from a firewall.
737 */
738 if (fw_enable && IPFW_LOADED && !args.next_hop) {
739 struct sockaddr_in *old = dst;
740
741 args.m = m;
742 args.next_hop = dst;
743 args.oif = ifp;
744 off = ip_fw_chk_ptr(&args);
745 m = args.m;
746 dst = args.next_hop;
747
748 /*
749 * On return we must do the following:
750 * m == NULL -> drop the pkt (old interface, deprecated)
751 * (off & IP_FW_PORT_DENY_FLAG) -> drop the pkt (new interface)
752 * 1<=off<= 0xffff -> DIVERT
753 * (off & IP_FW_PORT_DYNT_FLAG) -> send to a DUMMYNET pipe
754 * (off & IP_FW_PORT_TEE_FLAG) -> TEE the packet
755 * dst != old -> IPFIREWALL_FORWARD
756 * off==0, dst==old -> accept
757 * If some of the above modules are not compiled in, then
758 * we should't have to check the corresponding condition
759 * (because the ipfw control socket should not accept
760 * unsupported rules), but better play safe and drop
761 * packets in case of doubt.
762 */
763 if ( (off & IP_FW_PORT_DENY_FLAG) || m == NULL) {
764 if (m)
765 m_freem(m);
766 error = EACCES;
767 goto done;
768 }
769 ip = mtod(m, struct ip *);
770 if (off == 0 && dst == old) /* common case */
771 goto pass;
772 if (DUMMYNET_LOADED && (off & IP_FW_PORT_DYNT_FLAG) != 0) {
773 /*
774 * pass the pkt to dummynet. Need to include
775 * pipe number, m, ifp, ro, dst because these are
776 * not recomputed in the next pass.
777 * All other parameters have been already used and
778 * so they are not needed anymore.
779 * XXX note: if the ifp or ro entry are deleted
780 * while a pkt is in dummynet, we are in trouble!
781 */
782 args.ro = ro;
783 args.dst = dst;
784 args.flags = flags;
785
786 error = ip_dn_io_ptr(m, off & 0xffff, DN_TO_IP_OUT,
787 &args);
788 goto done;
789 }
790 #ifdef IPDIVERT
791 if (off != 0 && (off & IP_FW_PORT_DYNT_FLAG) == 0) {
792 struct mbuf *clone = NULL;
793
794 /* Clone packet if we're doing a 'tee' */
795 if ((off & IP_FW_PORT_TEE_FLAG) != 0)
796 clone = m_dup(m, M_DONTWAIT);
797
798 /*
799 * XXX
800 * delayed checksums are not currently compatible
801 * with divert sockets.
802 */
803 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
804 in_delayed_cksum(m);
805 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
806 }
807
808 /* Restore packet header fields to original values */
809 ip->ip_len = htons(ip->ip_len);
810 ip->ip_off = htons(ip->ip_off);
811
812 /* Deliver packet to divert input routine */
813 divert_packet(m, 0, off & 0xffff, args.divert_rule);
814
815 /* If 'tee', continue with original packet */
816 if (clone != NULL) {
817 m = clone;
818 ip = mtod(m, struct ip *);
819 goto pass;
820 }
821 goto done;
822 }
823 #endif
824
825 /* IPFIREWALL_FORWARD */
826 /*
827 * Check dst to make sure it is directly reachable on the
828 * interface we previously thought it was.
829 * If it isn't (which may be likely in some situations) we have
830 * to re-route it (ie, find a route for the next-hop and the
831 * associated interface) and set them here. This is nested
832 * forwarding which in most cases is undesirable, except where
833 * such control is nigh impossible. So we do it here.
834 * And I'm babbling.
835 */
836 if (off == 0 && old != dst) { /* FORWARD, dst has changed */
837 #if 0
838 /*
839 * XXX To improve readability, this block should be
840 * changed into a function call as below:
841 */
842 error = ip_ipforward(&m, &dst, &ifp);
843 if (error)
844 goto bad;
845 if (m == NULL) /* ip_input consumed the mbuf */
846 goto done;
847 #else
848 struct in_ifaddr *ia;
849
850 /*
851 * XXX sro_fwd below is static, and a pointer
852 * to it gets passed to routines downstream.
853 * This could have surprisingly bad results in
854 * practice, because its content is overwritten
855 * by subsequent packets.
856 */
857 /* There must be a better way to do this next line... */
858 static struct route sro_fwd;
859 struct route *ro_fwd = &sro_fwd;
860
861 #if 0
862 print_ip("IPFIREWALL_FORWARD: New dst ip: ",
863 dst->sin_addr, "\n");
864 #endif
865
866 /*
867 * We need to figure out if we have been forwarded
868 * to a local socket. If so, then we should somehow
869 * "loop back" to ip_input, and get directed to the
870 * PCB as if we had received this packet. This is
871 * because it may be dificult to identify the packets
872 * you want to forward until they are being output
873 * and have selected an interface. (e.g. locally
874 * initiated packets) If we used the loopback inteface,
875 * we would not be able to control what happens
876 * as the packet runs through ip_input() as
877 * it is done through a ISR.
878 */
879 LIST_FOREACH(ia,
880 INADDR_HASH(dst->sin_addr.s_addr), ia_hash) {
881 /*
882 * If the addr to forward to is one
883 * of ours, we pretend to
884 * be the destination for this packet.
885 */
886 if (IA_SIN(ia)->sin_addr.s_addr ==
887 dst->sin_addr.s_addr)
888 break;
889 }
890 if (ia) { /* tell ip_input "dont filter" */
891 struct m_hdr tag;
892
893 tag.mh_type = MT_TAG;
894 tag.mh_flags = PACKET_TAG_IPFORWARD;
895 tag.mh_data = (caddr_t)args.next_hop;
896 tag.mh_next = m;
897
898 if (m->m_pkthdr.rcvif == NULL)
899 m->m_pkthdr.rcvif = ifunit("lo0");
900 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
901 m->m_pkthdr.csum_flags |=
902 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
903 m0->m_pkthdr.csum_data = 0xffff;
904 }
905 m->m_pkthdr.csum_flags |=
906 CSUM_IP_CHECKED | CSUM_IP_VALID;
907 ip->ip_len = htons(ip->ip_len);
908 ip->ip_off = htons(ip->ip_off);
909 ip_input((struct mbuf *)&tag);
910 goto done;
911 }
912 /* Some of the logic for this was
913 * nicked from above.
914 *
915 * This rewrites the cached route in a local PCB.
916 * Is this what we want to do?
917 */
918 bcopy(dst, &ro_fwd->ro_dst, sizeof(*dst));
919
920 ro_fwd->ro_rt = 0;
921 rtalloc_ign(ro_fwd, RTF_PRCLONING);
922
923 if (ro_fwd->ro_rt == 0) {
924 ipstat.ips_noroute++;
925 error = EHOSTUNREACH;
926 goto bad;
927 }
928
929 ia = ifatoia(ro_fwd->ro_rt->rt_ifa);
930 ifp = ro_fwd->ro_rt->rt_ifp;
931 ro_fwd->ro_rt->rt_use++;
932 if (ro_fwd->ro_rt->rt_flags & RTF_GATEWAY)
933 dst = (struct sockaddr_in *)
934 ro_fwd->ro_rt->rt_gateway;
935 if (ro_fwd->ro_rt->rt_flags & RTF_HOST)
936 isbroadcast =
937 (ro_fwd->ro_rt->rt_flags & RTF_BROADCAST);
938 else
939 isbroadcast = in_broadcast(dst->sin_addr, ifp);
940 if (ro->ro_rt)
941 RTFREE(ro->ro_rt);
942 ro->ro_rt = ro_fwd->ro_rt;
943 dst = (struct sockaddr_in *)&ro_fwd->ro_dst;
944
945 #endif /* ... block to be put into a function */
946 /*
947 * If we added a default src ip earlier,
948 * which would have been gotten from the-then
949 * interface, do it again, from the new one.
950 */
951 if (src_was_INADDR_ANY)
952 ip->ip_src = IA_SIN(ia)->sin_addr;
953 goto pass ;
954 }
955
956 /*
957 * if we get here, none of the above matches, and
958 * we have to drop the pkt
959 */
960 m_freem(m);
961 error = EACCES; /* not sure this is the right error msg */
962 goto done;
963 }
964
965 pass:
966 /* 127/8 must not appear on wire - RFC1122. */
967 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
968 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
969 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
970 ipstat.ips_badaddr++;
971 error = EADDRNOTAVAIL;
972 goto bad;
973 }
974 }
975
976 m->m_pkthdr.csum_flags |= CSUM_IP;
977 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
978 if (sw_csum & CSUM_DELAY_DATA) {
979 in_delayed_cksum(m);
980 sw_csum &= ~CSUM_DELAY_DATA;
981 }
982 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
983
984 /*
985 * If small enough for interface, or the interface will take
986 * care of the fragmentation for us, can just send directly.
987 */
988 if ((u_short)ip->ip_len <= ifp->if_mtu ||
989 ifp->if_hwassist & CSUM_FRAGMENT) {
990 ip->ip_len = htons(ip->ip_len);
991 ip->ip_off = htons(ip->ip_off);
992 ip->ip_sum = 0;
993 if (sw_csum & CSUM_DELAY_IP)
994 ip->ip_sum = in_cksum(m, hlen);
995
996 /* Record statistics for this interface address. */
997 if (!(flags & IP_FORWARDING) && ia) {
998 ia->ia_ifa.if_opackets++;
999 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1000 }
1001
1002 #ifdef IPSEC
1003 /* clean ipsec history once it goes out of the node */
1004 ipsec_delaux(m);
1005 #endif
1006
1007 error = (*ifp->if_output)(ifp, m,
1008 (struct sockaddr *)dst, ro->ro_rt);
1009 goto done;
1010 }
1011 /*
1012 * Too large for interface; fragment if possible.
1013 * Must be able to put at least 8 bytes per fragment.
1014 */
1015 if (ip->ip_off & IP_DF) {
1016 error = EMSGSIZE;
1017 /*
1018 * This case can happen if the user changed the MTU
1019 * of an interface after enabling IP on it. Because
1020 * most netifs don't keep track of routes pointing to
1021 * them, there is no way for one to update all its
1022 * routes when the MTU is changed.
1023 */
1024 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST))
1025 && !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU)
1026 && (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) {
1027 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
1028 }
1029 ipstat.ips_cantfrag++;
1030 goto bad;
1031 }
1032 len = (ifp->if_mtu - hlen) &~ 7;
1033 if (len < 8) {
1034 error = EMSGSIZE;
1035 goto bad;
1036 }
1037
1038 /*
1039 * if the interface will not calculate checksums on
1040 * fragmented packets, then do it here.
1041 */
1042 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA &&
1043 (ifp->if_hwassist & CSUM_IP_FRAGS) == 0) {
1044 in_delayed_cksum(m);
1045 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1046 }
1047
1048 if (len > PAGE_SIZE) {
1049 /*
1050 * Fragement large datagrams such that each segment
1051 * contains a multiple of PAGE_SIZE amount of data,
1052 * plus headers. This enables a receiver to perform
1053 * page-flipping zero-copy optimizations.
1054 */
1055
1056 int newlen;
1057 struct mbuf *mtmp;
1058
1059 for (mtmp = m, off = 0;
1060 mtmp && ((off + mtmp->m_len) <= ifp->if_mtu);
1061 mtmp = mtmp->m_next) {
1062 off += mtmp->m_len;
1063 }
1064 /*
1065 * firstlen (off - hlen) must be aligned on an
1066 * 8-byte boundary
1067 */
1068 if (off < hlen)
1069 goto smart_frag_failure;
1070 off = ((off - hlen) & ~7) + hlen;
1071 newlen = (~PAGE_MASK) & ifp->if_mtu;
1072 if ((newlen + sizeof (struct ip)) > ifp->if_mtu) {
1073 /* we failed, go back the default */
1074 smart_frag_failure:
1075 newlen = len;
1076 off = hlen + len;
1077 }
1078
1079 /* printf("ipfrag: len = %d, hlen = %d, mhlen = %d, newlen = %d, off = %d\n",
1080 len, hlen, sizeof (struct ip), newlen, off);*/
1081
1082 len = newlen;
1083
1084 } else {
1085 off = hlen + len;
1086 }
1087
1088
1089
1090 {
1091 int mhlen, firstlen = off - hlen;
1092 struct mbuf **mnext = &m->m_nextpkt;
1093 int nfrags = 1;
1094
1095 /*
1096 * Loop through length of segment after first fragment,
1097 * make new header and copy data of each part and link onto chain.
1098 */
1099 m0 = m;
1100 mhlen = sizeof (struct ip);
1101 for (; off < (u_short)ip->ip_len; off += len) {
1102 MGETHDR(m, M_DONTWAIT, MT_HEADER);
1103 if (m == 0) {
1104 error = ENOBUFS;
1105 ipstat.ips_odropped++;
1106 goto sendorfree;
1107 }
1108 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
1109 m->m_data += max_linkhdr;
1110 mhip = mtod(m, struct ip *);
1111 *mhip = *ip;
1112 if (hlen > sizeof (struct ip)) {
1113 mhlen = ip_optcopy(ip, mhip) + sizeof (struct ip);
1114 mhip->ip_v = IPVERSION;
1115 mhip->ip_hl = mhlen >> 2;
1116 }
1117 m->m_len = mhlen;
1118 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
1119 if (off + len >= (u_short)ip->ip_len)
1120 len = (u_short)ip->ip_len - off;
1121 else
1122 mhip->ip_off |= IP_MF;
1123 mhip->ip_len = htons((u_short)(len + mhlen));
1124 m->m_next = m_copy(m0, off, len);
1125 if (m->m_next == 0) {
1126 (void) m_free(m);
1127 error = ENOBUFS; /* ??? */
1128 ipstat.ips_odropped++;
1129 goto sendorfree;
1130 }
1131 m->m_pkthdr.len = mhlen + len;
1132 m->m_pkthdr.rcvif = (struct ifnet *)0;
1133 #ifdef MAC
1134 mac_create_fragment(m0, m);
1135 #endif
1136 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
1137 mhip->ip_off = htons(mhip->ip_off);
1138 mhip->ip_sum = 0;
1139 if (sw_csum & CSUM_DELAY_IP)
1140 mhip->ip_sum = in_cksum(m, mhlen);
1141 *mnext = m;
1142 mnext = &m->m_nextpkt;
1143 nfrags++;
1144 }
1145 ipstat.ips_ofragments += nfrags;
1146
1147 /* set first/last markers for fragment chain */
1148 m->m_flags |= M_LASTFRAG;
1149 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1150 m0->m_pkthdr.csum_data = nfrags;
1151
1152 /*
1153 * Update first fragment by trimming what's been copied out
1154 * and updating header, then send each fragment (in order).
1155 */
1156 m = m0;
1157 m_adj(m, hlen + firstlen - (u_short)ip->ip_len);
1158 m->m_pkthdr.len = hlen + firstlen;
1159 ip->ip_len = htons((u_short)m->m_pkthdr.len);
1160 ip->ip_off |= IP_MF;
1161 ip->ip_off = htons(ip->ip_off);
1162 ip->ip_sum = 0;
1163 if (sw_csum & CSUM_DELAY_IP)
1164 ip->ip_sum = in_cksum(m, hlen);
1165 sendorfree:
1166 for (m = m0; m; m = m0) {
1167 m0 = m->m_nextpkt;
1168 m->m_nextpkt = 0;
1169 #ifdef IPSEC
1170 /* clean ipsec history once it goes out of the node */
1171 ipsec_delaux(m);
1172 #endif
1173 if (error == 0) {
1174 /* Record statistics for this interface address. */
1175 if (ia != NULL) {
1176 ia->ia_ifa.if_opackets++;
1177 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1178 }
1179
1180 error = (*ifp->if_output)(ifp, m,
1181 (struct sockaddr *)dst, ro->ro_rt);
1182 } else
1183 m_freem(m);
1184 }
1185
1186 if (error == 0)
1187 ipstat.ips_fragmented++;
1188 }
1189 done:
1190 #ifdef IPSEC
1191 if (ro == &iproute && ro->ro_rt) {
1192 RTFREE(ro->ro_rt);
1193 ro->ro_rt = NULL;
1194 }
1195 if (sp != NULL) {
1196 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1197 printf("DP ip_output call free SP:%p\n", sp));
1198 key_freesp(sp);
1199 }
1200 #endif /* IPSEC */
1201 #ifdef FAST_IPSEC
1202 if (ro == &iproute && ro->ro_rt) {
1203 RTFREE(ro->ro_rt);
1204 ro->ro_rt = NULL;
1205 }
1206 if (sp != NULL)
1207 KEY_FREESP(&sp);
1208 #endif /* FAST_IPSEC */
1209 return (error);
1210 bad:
1211 m_freem(m);
1212 goto done;
1213 }
1214
1215 void
1216 in_delayed_cksum(struct mbuf *m)
1217 {
1218 struct ip *ip;
1219 u_short csum, offset;
1220
1221 ip = mtod(m, struct ip *);
1222 offset = ip->ip_hl << 2 ;
1223 csum = in_cksum_skip(m, ip->ip_len, offset);
1224 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
1225 csum = 0xffff;
1226 offset += m->m_pkthdr.csum_data; /* checksum offset */
1227
1228 if (offset + sizeof(u_short) > m->m_len) {
1229 printf("delayed m_pullup, m->len: %d off: %d p: %d\n",
1230 m->m_len, offset, ip->ip_p);
1231 /*
1232 * XXX
1233 * this shouldn't happen, but if it does, the
1234 * correct behavior may be to insert the checksum
1235 * in the existing chain instead of rearranging it.
1236 */
1237 m = m_pullup(m, offset + sizeof(u_short));
1238 }
1239 *(u_short *)(m->m_data + offset) = csum;
1240 }
1241
1242 /*
1243 * Insert IP options into preformed packet.
1244 * Adjust IP destination as required for IP source routing,
1245 * as indicated by a non-zero in_addr at the start of the options.
1246 *
1247 * XXX This routine assumes that the packet has no options in place.
1248 */
1249 static struct mbuf *
1250 ip_insertoptions(m, opt, phlen)
1251 register struct mbuf *m;
1252 struct mbuf *opt;
1253 int *phlen;
1254 {
1255 register struct ipoption *p = mtod(opt, struct ipoption *);
1256 struct mbuf *n;
1257 register struct ip *ip = mtod(m, struct ip *);
1258 unsigned optlen;
1259
1260 optlen = opt->m_len - sizeof(p->ipopt_dst);
1261 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) {
1262 *phlen = 0;
1263 return (m); /* XXX should fail */
1264 }
1265 if (p->ipopt_dst.s_addr)
1266 ip->ip_dst = p->ipopt_dst;
1267 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
1268 MGETHDR(n, M_DONTWAIT, MT_HEADER);
1269 if (n == 0) {
1270 *phlen = 0;
1271 return (m);
1272 }
1273 n->m_pkthdr.rcvif = (struct ifnet *)0;
1274 #ifdef MAC
1275 mac_create_mbuf_from_mbuf(m, n);
1276 #endif
1277 n->m_pkthdr.len = m->m_pkthdr.len + optlen;
1278 m->m_len -= sizeof(struct ip);
1279 m->m_data += sizeof(struct ip);
1280 n->m_next = m;
1281 m = n;
1282 m->m_len = optlen + sizeof(struct ip);
1283 m->m_data += max_linkhdr;
1284 (void)memcpy(mtod(m, void *), ip, sizeof(struct ip));
1285 } else {
1286 m->m_data -= optlen;
1287 m->m_len += optlen;
1288 m->m_pkthdr.len += optlen;
1289 ovbcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
1290 }
1291 ip = mtod(m, struct ip *);
1292 bcopy(p->ipopt_list, ip + 1, optlen);
1293 *phlen = sizeof(struct ip) + optlen;
1294 ip->ip_v = IPVERSION;
1295 ip->ip_hl = *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(ip, jp)
1306 struct ip *ip, *jp;
1307 {
1308 register u_char *cp, *dp;
1309 int opt, optlen, cnt;
1310
1311 cp = (u_char *)(ip + 1);
1312 dp = (u_char *)(jp + 1);
1313 cnt = (ip->ip_hl << 2) - sizeof (struct ip);
1314 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1315 opt = cp[0];
1316 if (opt == IPOPT_EOL)
1317 break;
1318 if (opt == IPOPT_NOP) {
1319 /* Preserve for IP mcast tunnel's LSRR alignment. */
1320 *dp++ = IPOPT_NOP;
1321 optlen = 1;
1322 continue;
1323 }
1324
1325 KASSERT(cnt >= IPOPT_OLEN + sizeof(*cp),
1326 ("ip_optcopy: malformed ipv4 option"));
1327 optlen = cp[IPOPT_OLEN];
1328 KASSERT(optlen >= IPOPT_OLEN + sizeof(*cp) && optlen <= cnt,
1329 ("ip_optcopy: malformed ipv4 option"));
1330
1331 /* bogus lengths should have been caught by ip_dooptions */
1332 if (optlen > cnt)
1333 optlen = cnt;
1334 if (IPOPT_COPIED(opt)) {
1335 bcopy(cp, dp, optlen);
1336 dp += optlen;
1337 }
1338 }
1339 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
1340 *dp++ = IPOPT_EOL;
1341 return (optlen);
1342 }
1343
1344 /*
1345 * IP socket option processing.
1346 */
1347 int
1348 ip_ctloutput(so, sopt)
1349 struct socket *so;
1350 struct sockopt *sopt;
1351 {
1352 struct inpcb *inp = sotoinpcb(so);
1353 int error, optval;
1354
1355 error = optval = 0;
1356 if (sopt->sopt_level != IPPROTO_IP) {
1357 return (EINVAL);
1358 }
1359
1360 switch (sopt->sopt_dir) {
1361 case SOPT_SET:
1362 switch (sopt->sopt_name) {
1363 case IP_OPTIONS:
1364 #ifdef notyet
1365 case IP_RETOPTS:
1366 #endif
1367 {
1368 struct mbuf *m;
1369 if (sopt->sopt_valsize > MLEN) {
1370 error = EMSGSIZE;
1371 break;
1372 }
1373 MGET(m, sopt->sopt_td ? M_TRYWAIT : M_DONTWAIT, MT_HEADER);
1374 if (m == 0) {
1375 error = ENOBUFS;
1376 break;
1377 }
1378 m->m_len = sopt->sopt_valsize;
1379 error = sooptcopyin(sopt, mtod(m, char *), m->m_len,
1380 m->m_len);
1381
1382 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options,
1383 m));
1384 }
1385
1386 case IP_TOS:
1387 case IP_TTL:
1388 case IP_RECVOPTS:
1389 case IP_RECVRETOPTS:
1390 case IP_RECVDSTADDR:
1391 case IP_RECVIF:
1392 case IP_FAITH:
1393 error = sooptcopyin(sopt, &optval, sizeof optval,
1394 sizeof optval);
1395 if (error)
1396 break;
1397
1398 switch (sopt->sopt_name) {
1399 case IP_TOS:
1400 inp->inp_ip_tos = optval;
1401 break;
1402
1403 case IP_TTL:
1404 inp->inp_ip_ttl = optval;
1405 break;
1406 #define OPTSET(bit) \
1407 if (optval) \
1408 inp->inp_flags |= bit; \
1409 else \
1410 inp->inp_flags &= ~bit;
1411
1412 case IP_RECVOPTS:
1413 OPTSET(INP_RECVOPTS);
1414 break;
1415
1416 case IP_RECVRETOPTS:
1417 OPTSET(INP_RECVRETOPTS);
1418 break;
1419
1420 case IP_RECVDSTADDR:
1421 OPTSET(INP_RECVDSTADDR);
1422 break;
1423
1424 case IP_RECVIF:
1425 OPTSET(INP_RECVIF);
1426 break;
1427
1428 case IP_FAITH:
1429 OPTSET(INP_FAITH);
1430 break;
1431 }
1432 break;
1433 #undef OPTSET
1434
1435 case IP_MULTICAST_IF:
1436 case IP_MULTICAST_VIF:
1437 case IP_MULTICAST_TTL:
1438 case IP_MULTICAST_LOOP:
1439 case IP_ADD_MEMBERSHIP:
1440 case IP_DROP_MEMBERSHIP:
1441 error = ip_setmoptions(sopt, &inp->inp_moptions);
1442 break;
1443
1444 case IP_PORTRANGE:
1445 error = sooptcopyin(sopt, &optval, sizeof optval,
1446 sizeof optval);
1447 if (error)
1448 break;
1449
1450 switch (optval) {
1451 case IP_PORTRANGE_DEFAULT:
1452 inp->inp_flags &= ~(INP_LOWPORT);
1453 inp->inp_flags &= ~(INP_HIGHPORT);
1454 break;
1455
1456 case IP_PORTRANGE_HIGH:
1457 inp->inp_flags &= ~(INP_LOWPORT);
1458 inp->inp_flags |= INP_HIGHPORT;
1459 break;
1460
1461 case IP_PORTRANGE_LOW:
1462 inp->inp_flags &= ~(INP_HIGHPORT);
1463 inp->inp_flags |= INP_LOWPORT;
1464 break;
1465
1466 default:
1467 error = EINVAL;
1468 break;
1469 }
1470 break;
1471
1472 #if defined(IPSEC) || defined(FAST_IPSEC)
1473 case IP_IPSEC_POLICY:
1474 {
1475 caddr_t req;
1476 size_t len = 0;
1477 int priv;
1478 struct mbuf *m;
1479 int optname;
1480
1481 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1482 break;
1483 if ((error = soopt_mcopyin(sopt, m)) != 0) /* XXX */
1484 break;
1485 priv = (sopt->sopt_td != NULL &&
1486 suser(sopt->sopt_td) != 0) ? 0 : 1;
1487 req = mtod(m, caddr_t);
1488 len = m->m_len;
1489 optname = sopt->sopt_name;
1490 error = ipsec4_set_policy(inp, optname, req, len, priv);
1491 m_freem(m);
1492 break;
1493 }
1494 #endif /*IPSEC*/
1495
1496 default:
1497 error = ENOPROTOOPT;
1498 break;
1499 }
1500 break;
1501
1502 case SOPT_GET:
1503 switch (sopt->sopt_name) {
1504 case IP_OPTIONS:
1505 case IP_RETOPTS:
1506 if (inp->inp_options)
1507 error = sooptcopyout(sopt,
1508 mtod(inp->inp_options,
1509 char *),
1510 inp->inp_options->m_len);
1511 else
1512 sopt->sopt_valsize = 0;
1513 break;
1514
1515 case IP_TOS:
1516 case IP_TTL:
1517 case IP_RECVOPTS:
1518 case IP_RECVRETOPTS:
1519 case IP_RECVDSTADDR:
1520 case IP_RECVIF:
1521 case IP_PORTRANGE:
1522 case IP_FAITH:
1523 switch (sopt->sopt_name) {
1524
1525 case IP_TOS:
1526 optval = inp->inp_ip_tos;
1527 break;
1528
1529 case IP_TTL:
1530 optval = inp->inp_ip_ttl;
1531 break;
1532
1533 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1534
1535 case IP_RECVOPTS:
1536 optval = OPTBIT(INP_RECVOPTS);
1537 break;
1538
1539 case IP_RECVRETOPTS:
1540 optval = OPTBIT(INP_RECVRETOPTS);
1541 break;
1542
1543 case IP_RECVDSTADDR:
1544 optval = OPTBIT(INP_RECVDSTADDR);
1545 break;
1546
1547 case IP_RECVIF:
1548 optval = OPTBIT(INP_RECVIF);
1549 break;
1550
1551 case IP_PORTRANGE:
1552 if (inp->inp_flags & INP_HIGHPORT)
1553 optval = IP_PORTRANGE_HIGH;
1554 else if (inp->inp_flags & INP_LOWPORT)
1555 optval = IP_PORTRANGE_LOW;
1556 else
1557 optval = 0;
1558 break;
1559
1560 case IP_FAITH:
1561 optval = OPTBIT(INP_FAITH);
1562 break;
1563 }
1564 error = sooptcopyout(sopt, &optval, sizeof optval);
1565 break;
1566
1567 case IP_MULTICAST_IF:
1568 case IP_MULTICAST_VIF:
1569 case IP_MULTICAST_TTL:
1570 case IP_MULTICAST_LOOP:
1571 case IP_ADD_MEMBERSHIP:
1572 case IP_DROP_MEMBERSHIP:
1573 error = ip_getmoptions(sopt, inp->inp_moptions);
1574 break;
1575
1576 #if defined(IPSEC) || defined(FAST_IPSEC)
1577 case IP_IPSEC_POLICY:
1578 {
1579 struct mbuf *m = NULL;
1580 caddr_t req = NULL;
1581 size_t len = 0;
1582
1583 if (m != 0) {
1584 req = mtod(m, caddr_t);
1585 len = m->m_len;
1586 }
1587 error = ipsec4_get_policy(sotoinpcb(so), req, len, &m);
1588 if (error == 0)
1589 error = soopt_mcopyout(sopt, m); /* XXX */
1590 if (error == 0)
1591 m_freem(m);
1592 break;
1593 }
1594 #endif /*IPSEC*/
1595
1596 default:
1597 error = ENOPROTOOPT;
1598 break;
1599 }
1600 break;
1601 }
1602 return (error);
1603 }
1604
1605 /*
1606 * Set up IP options in pcb for insertion in output packets.
1607 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1608 * with destination address if source routed.
1609 */
1610 static int
1611 ip_pcbopts(optname, pcbopt, m)
1612 int optname;
1613 struct mbuf **pcbopt;
1614 register struct mbuf *m;
1615 {
1616 register int cnt, optlen;
1617 register u_char *cp;
1618 u_char opt;
1619
1620 /* turn off any old options */
1621 if (*pcbopt)
1622 (void)m_free(*pcbopt);
1623 *pcbopt = 0;
1624 if (m == (struct mbuf *)0 || m->m_len == 0) {
1625 /*
1626 * Only turning off any previous options.
1627 */
1628 if (m)
1629 (void)m_free(m);
1630 return (0);
1631 }
1632
1633 if (m->m_len % sizeof(int32_t))
1634 goto bad;
1635 /*
1636 * IP first-hop destination address will be stored before
1637 * actual options; move other options back
1638 * and clear it when none present.
1639 */
1640 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
1641 goto bad;
1642 cnt = m->m_len;
1643 m->m_len += sizeof(struct in_addr);
1644 cp = mtod(m, u_char *) + sizeof(struct in_addr);
1645 ovbcopy(mtod(m, caddr_t), (caddr_t)cp, (unsigned)cnt);
1646 bzero(mtod(m, caddr_t), sizeof(struct in_addr));
1647
1648 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1649 opt = cp[IPOPT_OPTVAL];
1650 if (opt == IPOPT_EOL)
1651 break;
1652 if (opt == IPOPT_NOP)
1653 optlen = 1;
1654 else {
1655 if (cnt < IPOPT_OLEN + sizeof(*cp))
1656 goto bad;
1657 optlen = cp[IPOPT_OLEN];
1658 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt)
1659 goto bad;
1660 }
1661 switch (opt) {
1662
1663 default:
1664 break;
1665
1666 case IPOPT_LSRR:
1667 case IPOPT_SSRR:
1668 /*
1669 * user process specifies route as:
1670 * ->A->B->C->D
1671 * D must be our final destination (but we can't
1672 * check that since we may not have connected yet).
1673 * A is first hop destination, which doesn't appear in
1674 * actual IP option, but is stored before the options.
1675 */
1676 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
1677 goto bad;
1678 m->m_len -= sizeof(struct in_addr);
1679 cnt -= sizeof(struct in_addr);
1680 optlen -= sizeof(struct in_addr);
1681 cp[IPOPT_OLEN] = optlen;
1682 /*
1683 * Move first hop before start of options.
1684 */
1685 bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
1686 sizeof(struct in_addr));
1687 /*
1688 * Then copy rest of options back
1689 * to close up the deleted entry.
1690 */
1691 ovbcopy((caddr_t)(&cp[IPOPT_OFFSET+1] +
1692 sizeof(struct in_addr)),
1693 (caddr_t)&cp[IPOPT_OFFSET+1],
1694 (unsigned)cnt + sizeof(struct in_addr));
1695 break;
1696 }
1697 }
1698 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
1699 goto bad;
1700 *pcbopt = m;
1701 return (0);
1702
1703 bad:
1704 (void)m_free(m);
1705 return (EINVAL);
1706 }
1707
1708 /*
1709 * XXX
1710 * The whole multicast option thing needs to be re-thought.
1711 * Several of these options are equally applicable to non-multicast
1712 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1713 * standard option (IP_TTL).
1714 */
1715
1716 /*
1717 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1718 */
1719 static struct ifnet *
1720 ip_multicast_if(a, ifindexp)
1721 struct in_addr *a;
1722 int *ifindexp;
1723 {
1724 int ifindex;
1725 struct ifnet *ifp;
1726
1727 if (ifindexp)
1728 *ifindexp = 0;
1729 if (ntohl(a->s_addr) >> 24 == 0) {
1730 ifindex = ntohl(a->s_addr) & 0xffffff;
1731 if (ifindex < 0 || if_index < ifindex)
1732 return NULL;
1733 ifp = ifnet_byindex(ifindex);
1734 if (ifindexp)
1735 *ifindexp = ifindex;
1736 } else {
1737 INADDR_TO_IFP(*a, ifp);
1738 }
1739 return ifp;
1740 }
1741
1742 /*
1743 * Set the IP multicast options in response to user setsockopt().
1744 */
1745 static int
1746 ip_setmoptions(sopt, imop)
1747 struct sockopt *sopt;
1748 struct ip_moptions **imop;
1749 {
1750 int error = 0;
1751 int i;
1752 struct in_addr addr;
1753 struct ip_mreq mreq;
1754 struct ifnet *ifp;
1755 struct ip_moptions *imo = *imop;
1756 struct route ro;
1757 struct sockaddr_in *dst;
1758 int ifindex;
1759 int s;
1760
1761 if (imo == NULL) {
1762 /*
1763 * No multicast option buffer attached to the pcb;
1764 * allocate one and initialize to default values.
1765 */
1766 imo = (struct ip_moptions*)malloc(sizeof(*imo), M_IPMOPTS,
1767 M_WAITOK);
1768
1769 if (imo == NULL)
1770 return (ENOBUFS);
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
1780 switch (sopt->sopt_name) {
1781 /* store an index number for the vif you wanna use in the send */
1782 case IP_MULTICAST_VIF:
1783 if (legal_vif_num == 0) {
1784 error = EOPNOTSUPP;
1785 break;
1786 }
1787 error = sooptcopyin(sopt, &i, sizeof i, sizeof i);
1788 if (error)
1789 break;
1790 if (!legal_vif_num(i) && (i != -1)) {
1791 error = EINVAL;
1792 break;
1793 }
1794 imo->imo_multicast_vif = i;
1795 break;
1796
1797 case IP_MULTICAST_IF:
1798 /*
1799 * Select the interface for outgoing multicast packets.
1800 */
1801 error = sooptcopyin(sopt, &addr, sizeof addr, sizeof addr);
1802 if (error)
1803 break;
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 s = splimp();
1819 ifp = ip_multicast_if(&addr, &ifindex);
1820 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
1821 splx(s);
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 splx(s);
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 = sooptcopyin(sopt, &ttl, 1, 1);
1843 if (error)
1844 break;
1845 imo->imo_multicast_ttl = ttl;
1846 } else {
1847 u_int ttl;
1848 error = sooptcopyin(sopt, &ttl, sizeof ttl,
1849 sizeof ttl);
1850 if (error)
1851 break;
1852 if (ttl > 255)
1853 error = EINVAL;
1854 else
1855 imo->imo_multicast_ttl = ttl;
1856 }
1857 break;
1858
1859 case IP_MULTICAST_LOOP:
1860 /*
1861 * Set the loopback flag for outgoing multicast packets.
1862 * Must be zero or one. The original multicast API required a
1863 * char argument, which is inconsistent with the rest
1864 * of the socket API. We allow either a char or an int.
1865 */
1866 if (sopt->sopt_valsize == 1) {
1867 u_char loop;
1868 error = sooptcopyin(sopt, &loop, 1, 1);
1869 if (error)
1870 break;
1871 imo->imo_multicast_loop = !!loop;
1872 } else {
1873 u_int loop;
1874 error = sooptcopyin(sopt, &loop, sizeof loop,
1875 sizeof loop);
1876 if (error)
1877 break;
1878 imo->imo_multicast_loop = !!loop;
1879 }
1880 break;
1881
1882 case IP_ADD_MEMBERSHIP:
1883 /*
1884 * Add a multicast group membership.
1885 * Group must be a valid IP multicast address.
1886 */
1887 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq);
1888 if (error)
1889 break;
1890
1891 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1892 error = EINVAL;
1893 break;
1894 }
1895 s = splimp();
1896 /*
1897 * If no interface address was provided, use the interface of
1898 * the route to the given multicast address.
1899 */
1900 if (mreq.imr_interface.s_addr == INADDR_ANY) {
1901 bzero((caddr_t)&ro, sizeof(ro));
1902 dst = (struct sockaddr_in *)&ro.ro_dst;
1903 dst->sin_len = sizeof(*dst);
1904 dst->sin_family = AF_INET;
1905 dst->sin_addr = mreq.imr_multiaddr;
1906 rtalloc(&ro);
1907 if (ro.ro_rt == NULL) {
1908 error = EADDRNOTAVAIL;
1909 splx(s);
1910 break;
1911 }
1912 ifp = ro.ro_rt->rt_ifp;
1913 rtfree(ro.ro_rt);
1914 }
1915 else {
1916 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1917 }
1918
1919 /*
1920 * See if we found an interface, and confirm that it
1921 * supports multicast.
1922 */
1923 if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
1924 error = EADDRNOTAVAIL;
1925 splx(s);
1926 break;
1927 }
1928 /*
1929 * See if the membership already exists or if all the
1930 * membership slots are full.
1931 */
1932 for (i = 0; i < imo->imo_num_memberships; ++i) {
1933 if (imo->imo_membership[i]->inm_ifp == ifp &&
1934 imo->imo_membership[i]->inm_addr.s_addr
1935 == mreq.imr_multiaddr.s_addr)
1936 break;
1937 }
1938 if (i < imo->imo_num_memberships) {
1939 error = EADDRINUSE;
1940 splx(s);
1941 break;
1942 }
1943 if (i == IP_MAX_MEMBERSHIPS) {
1944 error = ETOOMANYREFS;
1945 splx(s);
1946 break;
1947 }
1948 /*
1949 * Everything looks good; add a new record to the multicast
1950 * address list for the given interface.
1951 */
1952 if ((imo->imo_membership[i] =
1953 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) {
1954 error = ENOBUFS;
1955 splx(s);
1956 break;
1957 }
1958 ++imo->imo_num_memberships;
1959 splx(s);
1960 break;
1961
1962 case IP_DROP_MEMBERSHIP:
1963 /*
1964 * Drop a multicast group membership.
1965 * Group must be a valid IP multicast address.
1966 */
1967 error = sooptcopyin(sopt, &mreq, sizeof mreq, sizeof mreq);
1968 if (error)
1969 break;
1970
1971 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1972 error = EINVAL;
1973 break;
1974 }
1975
1976 s = splimp();
1977 /*
1978 * If an interface address was specified, get a pointer
1979 * to its ifnet structure.
1980 */
1981 if (mreq.imr_interface.s_addr == INADDR_ANY)
1982 ifp = NULL;
1983 else {
1984 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1985 if (ifp == NULL) {
1986 error = EADDRNOTAVAIL;
1987 splx(s);
1988 break;
1989 }
1990 }
1991 /*
1992 * Find the membership in the membership array.
1993 */
1994 for (i = 0; i < imo->imo_num_memberships; ++i) {
1995 if ((ifp == NULL ||
1996 imo->imo_membership[i]->inm_ifp == ifp) &&
1997 imo->imo_membership[i]->inm_addr.s_addr ==
1998 mreq.imr_multiaddr.s_addr)
1999 break;
2000 }
2001 if (i == imo->imo_num_memberships) {
2002 error = EADDRNOTAVAIL;
2003 splx(s);
2004 break;
2005 }
2006 /*
2007 * Give up the multicast address record to which the
2008 * membership points.
2009 */
2010 in_delmulti(imo->imo_membership[i]);
2011 /*
2012 * Remove the gap in the membership array.
2013 */
2014 for (++i; i < imo->imo_num_memberships; ++i)
2015 imo->imo_membership[i-1] = imo->imo_membership[i];
2016 --imo->imo_num_memberships;
2017 splx(s);
2018 break;
2019
2020 default:
2021 error = EOPNOTSUPP;
2022 break;
2023 }
2024
2025 /*
2026 * If all options have default values, no need to keep the mbuf.
2027 */
2028 if (imo->imo_multicast_ifp == NULL &&
2029 imo->imo_multicast_vif == -1 &&
2030 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
2031 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
2032 imo->imo_num_memberships == 0) {
2033 free(*imop, M_IPMOPTS);
2034 *imop = NULL;
2035 }
2036
2037 return (error);
2038 }
2039
2040 /*
2041 * Return the IP multicast options in response to user getsockopt().
2042 */
2043 static int
2044 ip_getmoptions(sopt, imo)
2045 struct sockopt *sopt;
2046 register 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 error = sooptcopyout(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 IFP_TO_IA(imo->imo_multicast_ifp, ia);
2071 addr.s_addr = (ia == NULL) ? INADDR_ANY
2072 : IA_SIN(ia)->sin_addr.s_addr;
2073 }
2074 error = sooptcopyout(sopt, &addr, sizeof addr);
2075 break;
2076
2077 case IP_MULTICAST_TTL:
2078 if (imo == 0)
2079 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
2080 else
2081 optval = coptval = imo->imo_multicast_ttl;
2082 if (sopt->sopt_valsize == 1)
2083 error = sooptcopyout(sopt, &coptval, 1);
2084 else
2085 error = sooptcopyout(sopt, &optval, sizeof optval);
2086 break;
2087
2088 case IP_MULTICAST_LOOP:
2089 if (imo == 0)
2090 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
2091 else
2092 optval = coptval = imo->imo_multicast_loop;
2093 if (sopt->sopt_valsize == 1)
2094 error = sooptcopyout(sopt, &coptval, 1);
2095 else
2096 error = sooptcopyout(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(imo)
2111 register struct ip_moptions *imo;
2112 {
2113 register int i;
2114
2115 if (imo != NULL) {
2116 for (i = 0; i < imo->imo_num_memberships; ++i)
2117 in_delmulti(imo->imo_membership[i]);
2118 free(imo, M_IPMOPTS);
2119 }
2120 }
2121
2122 /*
2123 * Routine called from ip_output() to loop back a copy of an IP multicast
2124 * packet to the input queue of a specified interface. Note that this
2125 * calls the output routine of the loopback "driver", but with an interface
2126 * pointer that might NOT be a loopback interface -- evil, but easier than
2127 * replicating that code here.
2128 */
2129 static void
2130 ip_mloopback(ifp, m, dst, hlen)
2131 struct ifnet *ifp;
2132 register struct mbuf *m;
2133 register struct sockaddr_in *dst;
2134 int hlen;
2135 {
2136 register struct ip *ip;
2137 struct mbuf *copym;
2138
2139 copym = m_copy(m, 0, M_COPYALL);
2140 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
2141 copym = m_pullup(copym, hlen);
2142 if (copym != NULL) {
2143 /*
2144 * We don't bother to fragment if the IP length is greater
2145 * than the interface's MTU. Can this possibly matter?
2146 */
2147 ip = mtod(copym, struct ip *);
2148 ip->ip_len = htons(ip->ip_len);
2149 ip->ip_off = htons(ip->ip_off);
2150 ip->ip_sum = 0;
2151 ip->ip_sum = in_cksum(copym, hlen);
2152 /*
2153 * NB:
2154 * It's not clear whether there are any lingering
2155 * reentrancy problems in other areas which might
2156 * be exposed by using ip_input directly (in
2157 * particular, everything which modifies the packet
2158 * in-place). Yet another option is using the
2159 * protosw directly to deliver the looped back
2160 * packet. For the moment, we'll err on the side
2161 * of safety by using if_simloop().
2162 */
2163 #if 1 /* XXX */
2164 if (dst->sin_family != AF_INET) {
2165 printf("ip_mloopback: bad address family %d\n",
2166 dst->sin_family);
2167 dst->sin_family = AF_INET;
2168 }
2169 #endif
2170
2171 #ifdef notdef
2172 copym->m_pkthdr.rcvif = ifp;
2173 ip_input(copym);
2174 #else
2175 /* if the checksum hasn't been computed, mark it as valid */
2176 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2177 copym->m_pkthdr.csum_flags |=
2178 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2179 copym->m_pkthdr.csum_data = 0xffff;
2180 }
2181 if_simloop(ifp, copym, dst->sin_family, 0);
2182 #endif
2183 }
2184 }
Cache object: a6bb0b179d23030421ac84f262b37d95
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