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HAMMER 60I/Many: Mirroring
[dragonfly.git] / sys / netinet / ip_output.c
blobf7b0de58b58c03ad8f9f33ac4f2461240347cd49
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 1.46 2008/07/07 22:02:10 nant 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/sysctl.h>
54 #include <sys/thread2.h>
55 #include <sys/in_cksum.h>
56
57 #include <net/if.h>
58 #include <net/netisr.h>
59 #include <net/pfil.h>
60 #include <net/route.h>
61
62 #include <netinet/in.h>
63 #include <netinet/in_systm.h>
64 #include <netinet/ip.h>
65 #include <netinet/in_pcb.h>
66 #include <netinet/in_var.h>
67 #include <netinet/ip_var.h>
68
69 #include <netproto/mpls/mpls_var.h>
70
71 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options");
72
73 #ifdef IPSEC
74 #include <netinet6/ipsec.h>
75 #include <netproto/key/key.h>
76 #ifdef IPSEC_DEBUG
77 #include <netproto/key/key_debug.h>
78 #else
79 #define KEYDEBUG(lev,arg)
80 #endif
81 #endif /*IPSEC*/
82
83 #ifdef FAST_IPSEC
84 #include <netproto/ipsec/ipsec.h>
85 #include <netproto/ipsec/xform.h>
86 #include <netproto/ipsec/key.h>
87 #endif /*FAST_IPSEC*/
88
89 #include <net/ipfw/ip_fw.h>
90 #include <net/dummynet/ip_dummynet.h>
91
92 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\
93 x, (ntohl(a.s_addr)>>24)&0xFF,\
94 (ntohl(a.s_addr)>>16)&0xFF,\
95 (ntohl(a.s_addr)>>8)&0xFF,\
96 (ntohl(a.s_addr))&0xFF, y);
97
98 u_short ip_id;
99
100 #ifdef MBUF_STRESS_TEST
101 int mbuf_frag_size = 0;
102 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
103 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
104 #endif
105
106 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *);
107 static struct ifnet *ip_multicast_if(struct in_addr *, int *);
108 static void ip_mloopback
109 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int);
110 static int ip_getmoptions
111 (struct sockopt *, struct ip_moptions *);
112 static int ip_pcbopts(int, struct mbuf **, struct mbuf *);
113 static int ip_setmoptions
114 (struct sockopt *, struct ip_moptions **);
115
116 int ip_optcopy(struct ip *, struct ip *);
117
118
119 extern struct protosw inetsw[];
120
121 /*
122 * IP output. The packet in mbuf chain m contains a skeletal IP
123 * header (with len, off, ttl, proto, tos, src, dst).
124 * The mbuf chain containing the packet will be freed.
125 * The mbuf opt, if present, will not be freed.
126 */
127 int
128 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro,
129 int flags, struct ip_moptions *imo, struct inpcb *inp)
130 {
131 struct ip *ip;
132 struct ifnet *ifp = NULL; /* keep compiler happy */
133 struct mbuf *m;
134 int hlen = sizeof(struct ip);
135 int len, off, error = 0;
136 struct sockaddr_in *dst = NULL; /* keep compiler happy */
137 struct in_ifaddr *ia = NULL;
138 int isbroadcast, sw_csum;
139 struct in_addr pkt_dst;
140 struct route iproute;
141 struct m_tag *dn_mtag = NULL;
142 #ifdef IPSEC
143 struct secpolicy *sp = NULL;
144 struct socket *so = inp ? inp->inp_socket : NULL;
145 #endif
146 #ifdef FAST_IPSEC
147 struct m_tag *mtag;
148 struct secpolicy *sp = NULL;
149 struct tdb_ident *tdbi;
150 #endif /* FAST_IPSEC */
151 struct ip_fw_args args;
152 int src_was_INADDR_ANY = 0; /* as the name says... */
153
154 args.eh = NULL;
155 args.rule = NULL;
156 args.next_hop = NULL;
157
158 /* Grab info from MT_TAG mbufs prepended to the chain. */
159 while (m0 != NULL && m0->m_type == MT_TAG) {
160 switch(m0->_m_tag_id) {
161 case PACKET_TAG_IPFORWARD:
162 args.next_hop = (struct sockaddr_in *)m0->m_data;
163 break;
164 default:
165 kprintf("ip_output: unrecognised MT_TAG tag %d\n",
166 m0->_m_tag_id);
167 break;
168 }
169 m0 = m0->m_next;
170 }
171 m = m0;
172 M_ASSERTPKTHDR(m);
173
174 /* Extract info from dummynet tag */
175 dn_mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
176 if (dn_mtag != NULL) {
177 struct dn_pkt *dn_pkt = m_tag_data(dn_mtag);
178
179 /*
180 * The packet was already tagged, so part of the
181 * processing was already done, and we need to go down.
182 * Get parameters from the tag.
183 */
184 args.rule = dn_pkt->dn_priv;
185 opt = NULL;
186 ro = &dn_pkt->ro;
187 imo = NULL;
188 dst = dn_pkt->dn_dst;
189 ifp = dn_pkt->ifp;
190 flags = dn_pkt->flags;
191
192 /*
193 * Don't delete the dummynet tag here, just unlink it,
194 * since some local variables (like 'ro' and 'dst') are
195 * still referencing certain parts of it.
196 * The dummynet tag will be freed at the end of the
197 * output process.
198 */
199 m_tag_unlink(m, dn_mtag);
200 }
201
202 if (ro == NULL) {
203 ro = &iproute;
204 bzero(ro, sizeof *ro);
205 }
206
207 if (args.rule != NULL) { /* dummynet already saw us */
208 ip = mtod(m, struct ip *);
209 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ;
210 if (ro->ro_rt)
211 ia = ifatoia(ro->ro_rt->rt_ifa);
212 goto sendit;
213 }
214
215 if (opt) {
216 len = 0;
217 m = ip_insertoptions(m, opt, &len);
218 if (len != 0)
219 hlen = len;
220 }
221 ip = mtod(m, struct ip *);
222 pkt_dst = args.next_hop ? args.next_hop->sin_addr : ip->ip_dst;
223
224 /*
225 * Fill in IP header.
226 */
227 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) {
228 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2);
229 ip->ip_off &= IP_DF;
230 ip->ip_id = ip_newid();
231 ipstat.ips_localout++;
232 } else {
233 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
234 }
235
236 dst = (struct sockaddr_in *)&ro->ro_dst;
237 /*
238 * If there is a cached route,
239 * check that it is to the same destination
240 * and is still up. If not, free it and try again.
241 * The address family should also be checked in case of sharing the
242 * cache with IPv6.
243 */
244 if (ro->ro_rt &&
245 (!(ro->ro_rt->rt_flags & RTF_UP) ||
246 dst->sin_family != AF_INET ||
247 dst->sin_addr.s_addr != pkt_dst.s_addr)) {
248 rtfree(ro->ro_rt);
249 ro->ro_rt = (struct rtentry *)NULL;
250 }
251 if (ro->ro_rt == NULL) {
252 bzero(dst, sizeof *dst);
253 dst->sin_family = AF_INET;
254 dst->sin_len = sizeof *dst;
255 dst->sin_addr = pkt_dst;
256 }
257 /*
258 * If routing to interface only,
259 * short circuit routing lookup.
260 */
261 if (flags & IP_ROUTETOIF) {
262 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL &&
263 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) {
264 ipstat.ips_noroute++;
265 error = ENETUNREACH;
266 goto bad;
267 }
268 ifp = ia->ia_ifp;
269 ip->ip_ttl = 1;
270 isbroadcast = in_broadcast(dst->sin_addr, ifp);
271 } else if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
272 imo != NULL && imo->imo_multicast_ifp != NULL) {
273 /*
274 * Bypass the normal routing lookup for multicast
275 * packets if the interface is specified.
276 */
277 ifp = imo->imo_multicast_ifp;
278 ia = IFP_TO_IA(ifp);
279 isbroadcast = 0; /* fool gcc */
280 } else {
281 /*
282 * If this is the case, we probably don't want to allocate
283 * a protocol-cloned route since we didn't get one from the
284 * ULP. This lets TCP do its thing, while not burdening
285 * forwarding or ICMP with the overhead of cloning a route.
286 * Of course, we still want to do any cloning requested by
287 * the link layer, as this is probably required in all cases
288 * for correct operation (as it is for ARP).
289 */
290 if (ro->ro_rt == NULL)
291 rtalloc_ign(ro, RTF_PRCLONING);
292 if (ro->ro_rt == NULL) {
293 ipstat.ips_noroute++;
294 error = EHOSTUNREACH;
295 goto bad;
296 }
297 ia = ifatoia(ro->ro_rt->rt_ifa);
298 ifp = ro->ro_rt->rt_ifp;
299 ro->ro_rt->rt_use++;
300 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
301 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
302 if (ro->ro_rt->rt_flags & RTF_HOST)
303 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
304 else
305 isbroadcast = in_broadcast(dst->sin_addr, ifp);
306 }
307 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
308 struct in_multi *inm;
309
310 m->m_flags |= M_MCAST;
311 /*
312 * IP destination address is multicast. Make sure "dst"
313 * still points to the address in "ro". (It may have been
314 * changed to point to a gateway address, above.)
315 */
316 dst = (struct sockaddr_in *)&ro->ro_dst;
317 /*
318 * See if the caller provided any multicast options
319 */
320 if (imo != NULL) {
321 ip->ip_ttl = imo->imo_multicast_ttl;
322 if (imo->imo_multicast_vif != -1)
323 ip->ip_src.s_addr =
324 ip_mcast_src ?
325 ip_mcast_src(imo->imo_multicast_vif) :
326 INADDR_ANY;
327 } else
328 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
329 /*
330 * Confirm that the outgoing interface supports multicast.
331 */
332 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
333 if (!(ifp->if_flags & IFF_MULTICAST)) {
334 ipstat.ips_noroute++;
335 error = ENETUNREACH;
336 goto bad;
337 }
338 }
339 /*
340 * If source address not specified yet, use address
341 * of outgoing interface.
342 */
343 if (ip->ip_src.s_addr == INADDR_ANY) {
344 /* Interface may have no addresses. */
345 if (ia != NULL)
346 ip->ip_src = IA_SIN(ia)->sin_addr;
347 }
348
349 IN_LOOKUP_MULTI(pkt_dst, ifp, inm);
350 if (inm != NULL &&
351 (imo == NULL || imo->imo_multicast_loop)) {
352 /*
353 * If we belong to the destination multicast group
354 * on the outgoing interface, and the caller did not
355 * forbid loopback, loop back a copy.
356 */
357 ip_mloopback(ifp, m, dst, hlen);
358 }
359 else {
360 /*
361 * If we are acting as a multicast router, perform
362 * multicast forwarding as if the packet had just
363 * arrived on the interface to which we are about
364 * to send. The multicast forwarding function
365 * recursively calls this function, using the
366 * IP_FORWARDING flag to prevent infinite recursion.
367 *
368 * Multicasts that are looped back by ip_mloopback(),
369 * above, will be forwarded by the ip_input() routine,
370 * if necessary.
371 */
372 if (ip_mrouter && !(flags & IP_FORWARDING)) {
373 /*
374 * If rsvp daemon is not running, do not
375 * set ip_moptions. This ensures that the packet
376 * is multicast and not just sent down one link
377 * as prescribed by rsvpd.
378 */
379 if (!rsvp_on)
380 imo = NULL;
381 if (ip_mforward &&
382 ip_mforward(ip, ifp, m, imo) != 0) {
383 m_freem(m);
384 goto done;
385 }
386 }
387 }
388
389 /*
390 * Multicasts with a time-to-live of zero may be looped-
391 * back, above, but must not be transmitted on a network.
392 * Also, multicasts addressed to the loopback interface
393 * are not sent -- the above call to ip_mloopback() will
394 * loop back a copy if this host actually belongs to the
395 * destination group on the loopback interface.
396 */
397 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
398 m_freem(m);
399 goto done;
400 }
401
402 goto sendit;
403 }
404 #ifndef notdef
405 /*
406 * If the source address is not specified yet, use the address
407 * of the outoing interface. In case, keep note we did that, so
408 * if the the firewall changes the next-hop causing the output
409 * interface to change, we can fix that.
410 */
411 if (ip->ip_src.s_addr == INADDR_ANY) {
412 /* Interface may have no addresses. */
413 if (ia != NULL) {
414 ip->ip_src = IA_SIN(ia)->sin_addr;
415 src_was_INADDR_ANY = 1;
416 }
417 }
418 #endif /* notdef */
419 #ifdef ALTQ
420 /*
421 * Disable packet drop hack.
422 * Packetdrop should be done by queueing.
423 */
424 #else /* !ALTQ */
425 /*
426 * Verify that we have any chance at all of being able to queue
427 * the packet or packet fragments
428 */
429 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >=
430 ifp->if_snd.ifq_maxlen) {
431 error = ENOBUFS;
432 ipstat.ips_odropped++;
433 goto bad;
434 }
435 #endif /* !ALTQ */
436
437 /*
438 * Look for broadcast address and
439 * verify user is allowed to send
440 * such a packet.
441 */
442 if (isbroadcast) {
443 if (!(ifp->if_flags & IFF_BROADCAST)) {
444 error = EADDRNOTAVAIL;
445 goto bad;
446 }
447 if (!(flags & IP_ALLOWBROADCAST)) {
448 error = EACCES;
449 goto bad;
450 }
451 /* don't allow broadcast messages to be fragmented */
452 if (ip->ip_len > ifp->if_mtu) {
453 error = EMSGSIZE;
454 goto bad;
455 }
456 m->m_flags |= M_BCAST;
457 } else {
458 m->m_flags &= ~M_BCAST;
459 }
460
461 sendit:
462 #ifdef IPSEC
463 /* get SP for this packet */
464 if (so == NULL)
465 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error);
466 else
467 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
468
469 if (sp == NULL) {
470 ipsecstat.out_inval++;
471 goto bad;
472 }
473
474 error = 0;
475
476 /* check policy */
477 switch (sp->policy) {
478 case IPSEC_POLICY_DISCARD:
479 /*
480 * This packet is just discarded.
481 */
482 ipsecstat.out_polvio++;
483 goto bad;
484
485 case IPSEC_POLICY_BYPASS:
486 case IPSEC_POLICY_NONE:
487 /* no need to do IPsec. */
488 goto skip_ipsec;
489
490 case IPSEC_POLICY_IPSEC:
491 if (sp->req == NULL) {
492 /* acquire a policy */
493 error = key_spdacquire(sp);
494 goto bad;
495 }
496 break;
497
498 case IPSEC_POLICY_ENTRUST:
499 default:
500 kprintf("ip_output: Invalid policy found. %d\n", sp->policy);
501 }
502 {
503 struct ipsec_output_state state;
504 bzero(&state, sizeof state);
505 state.m = m;
506 if (flags & IP_ROUTETOIF) {
507 state.ro = &iproute;
508 bzero(&iproute, sizeof iproute);
509 } else
510 state.ro = ro;
511 state.dst = (struct sockaddr *)dst;
512
513 ip->ip_sum = 0;
514
515 /*
516 * XXX
517 * delayed checksums are not currently compatible with IPsec
518 */
519 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
520 in_delayed_cksum(m);
521 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
522 }
523
524 ip->ip_len = htons(ip->ip_len);
525 ip->ip_off = htons(ip->ip_off);
526
527 error = ipsec4_output(&state, sp, flags);
528
529 m = state.m;
530 if (flags & IP_ROUTETOIF) {
531 /*
532 * if we have tunnel mode SA, we may need to ignore
533 * IP_ROUTETOIF.
534 */
535 if (state.ro != &iproute || state.ro->ro_rt != NULL) {
536 flags &= ~IP_ROUTETOIF;
537 ro = state.ro;
538 }
539 } else
540 ro = state.ro;
541 dst = (struct sockaddr_in *)state.dst;
542 if (error) {
543 /* mbuf is already reclaimed in ipsec4_output. */
544 m0 = NULL;
545 switch (error) {
546 case EHOSTUNREACH:
547 case ENETUNREACH:
548 case EMSGSIZE:
549 case ENOBUFS:
550 case ENOMEM:
551 break;
552 default:
553 kprintf("ip4_output (ipsec): error code %d\n", error);
554 /*fall through*/
555 case ENOENT:
556 /* don't show these error codes to the user */
557 error = 0;
558 break;
559 }
560 goto bad;
561 }
562 }
563
564 /* be sure to update variables that are affected by ipsec4_output() */
565 ip = mtod(m, struct ip *);
566 #ifdef _IP_VHL
567 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
568 #else
569 hlen = ip->ip_hl << 2;
570 #endif
571 if (ro->ro_rt == NULL) {
572 if (!(flags & IP_ROUTETOIF)) {
573 kprintf("ip_output: "
574 "can't update route after IPsec processing\n");
575 error = EHOSTUNREACH; /*XXX*/
576 goto bad;
577 }
578 } else {
579 ia = ifatoia(ro->ro_rt->rt_ifa);
580 ifp = ro->ro_rt->rt_ifp;
581 }
582
583 /* make it flipped, again. */
584 ip->ip_len = ntohs(ip->ip_len);
585 ip->ip_off = ntohs(ip->ip_off);
586 skip_ipsec:
587 #endif /*IPSEC*/
588 #ifdef FAST_IPSEC
589 /*
590 * Check the security policy (SP) for the packet and, if
591 * required, do IPsec-related processing. There are two
592 * cases here; the first time a packet is sent through
593 * it will be untagged and handled by ipsec4_checkpolicy.
594 * If the packet is resubmitted to ip_output (e.g. after
595 * AH, ESP, etc. processing), there will be a tag to bypass
596 * the lookup and related policy checking.
597 */
598 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
599 crit_enter();
600 if (mtag != NULL) {
601 tdbi = (struct tdb_ident *)m_tag_data(mtag);
602 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
603 if (sp == NULL)
604 error = -EINVAL; /* force silent drop */
605 m_tag_delete(m, mtag);
606 } else {
607 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags,
608 &error, inp);
609 }
610 /*
611 * There are four return cases:
612 * sp != NULL apply IPsec policy
613 * sp == NULL, error == 0 no IPsec handling needed
614 * sp == NULL, error == -EINVAL discard packet w/o error
615 * sp == NULL, error != 0 discard packet, report error
616 */
617 if (sp != NULL) {
618 /* Loop detection, check if ipsec processing already done */
619 KASSERT(sp->req != NULL, ("ip_output: no ipsec request"));
620 for (mtag = m_tag_first(m); mtag != NULL;
621 mtag = m_tag_next(m, mtag)) {
622 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
623 continue;
624 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
625 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
626 continue;
627 /*
628 * Check if policy has an SA associated with it.
629 * This can happen when an SP has yet to acquire
630 * an SA; e.g. on first reference. If it occurs,
631 * then we let ipsec4_process_packet do its thing.
632 */
633 if (sp->req->sav == NULL)
634 break;
635 tdbi = (struct tdb_ident *)m_tag_data(mtag);
636 if (tdbi->spi == sp->req->sav->spi &&
637 tdbi->proto == sp->req->sav->sah->saidx.proto &&
638 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst,
639 sizeof(union sockaddr_union)) == 0) {
640 /*
641 * No IPsec processing is needed, free
642 * reference to SP.
643 *
644 * NB: null pointer to avoid free at
645 * done: below.
646 */
647 KEY_FREESP(&sp), sp = NULL;
648 crit_exit();
649 goto spd_done;
650 }
651 }
652
653 /*
654 * Do delayed checksums now because we send before
655 * this is done in the normal processing path.
656 */
657 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
658 in_delayed_cksum(m);
659 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
660 }
661
662 ip->ip_len = htons(ip->ip_len);
663 ip->ip_off = htons(ip->ip_off);
664
665 /* NB: callee frees mbuf */
666 error = ipsec4_process_packet(m, sp->req, flags, 0);
667 /*
668 * Preserve KAME behaviour: ENOENT can be returned
669 * when an SA acquire is in progress. Don't propagate
670 * this to user-level; it confuses applications.
671 *
672 * XXX this will go away when the SADB is redone.
673 */
674 if (error == ENOENT)
675 error = 0;
676 crit_exit();
677 goto done;
678 } else {
679 crit_exit();
680
681 if (error != 0) {
682 /*
683 * Hack: -EINVAL is used to signal that a packet
684 * should be silently discarded. This is typically
685 * because we asked key management for an SA and
686 * it was delayed (e.g. kicked up to IKE).
687 */
688 if (error == -EINVAL)
689 error = 0;
690 goto bad;
691 } else {
692 /* No IPsec processing for this packet. */
693 }
694 #ifdef notyet
695 /*
696 * If deferred crypto processing is needed, check that
697 * the interface supports it.
698 */
699 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL);
700 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) {
701 /* notify IPsec to do its own crypto */
702 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag));
703 error = EHOSTUNREACH;
704 goto bad;
705 }
706 #endif
707 }
708 spd_done:
709 #endif /* FAST_IPSEC */
710 /*
711 * IpHack's section.
712 * - Xlate: translate packet's addr/port (NAT).
713 * - Firewall: deny/allow/etc.
714 * - Wrap: fake packet's addr/port <unimpl.>
715 * - Encapsulate: put it in another IP and send out. <unimp.>
716 */
717
718 /*
719 * Run through list of hooks for output packets.
720 */
721 if (pfil_has_hooks(&inet_pfil_hook)) {
722 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT);
723 if (error != 0 || m == NULL)
724 goto done;
725 ip = mtod(m, struct ip *);
726 }
727
728 /*
729 * Check with the firewall...
730 * but not if we are already being fwd'd from a firewall.
731 */
732 if (fw_enable && IPFW_LOADED && !args.next_hop) {
733 struct sockaddr_in *old = dst;
734
735 args.m = m;
736 args.next_hop = dst;
737 args.oif = ifp;
738 off = ip_fw_chk_ptr(&args);
739 m = args.m;
740 dst = args.next_hop;
741
742 /*
743 * On return we must do the following:
744 * m == NULL -> drop the pkt (old interface, deprecated)
745 * (off & IP_FW_PORT_DENY_FLAG) -> drop the pkt (new interface)
746 * 1<=off<= 0xffff -> DIVERT
747 * (off & IP_FW_PORT_DYNT_FLAG) -> send to a DUMMYNET pipe
748 * (off & IP_FW_PORT_TEE_FLAG) -> TEE the packet
749 * dst != old -> IPFIREWALL_FORWARD
750 * off==0, dst==old -> accept
751 * If some of the above modules are not compiled in, then
752 * we should't have to check the corresponding condition
753 * (because the ipfw control socket should not accept
754 * unsupported rules), but better play safe and drop
755 * packets in case of doubt.
756 */
757 if ( (off & IP_FW_PORT_DENY_FLAG) || m == NULL) {
758 if (m)
759 m_freem(m);
760 error = EACCES;
761 goto done;
762 }
763 ip = mtod(m, struct ip *);
764 if (off == 0 && dst == old) /* common case */
765 goto pass;
766 if (off & IP_FW_PORT_DYNT_FLAG) {
767 /*
768 * pass the pkt to dummynet. Need to include
769 * pipe number, m, ifp, ro, dst because these are
770 * not recomputed in the next pass.
771 * All other parameters have been already used and
772 * so they are not needed anymore.
773 * XXX note: if the ifp or ro entry are deleted
774 * while a pkt is in dummynet, we are in trouble!
775 */
776 args.ro = ro;
777 args.dst = dst;
778 args.flags = flags;
779
780 error = 0;
781 ip_fw_dn_io_ptr(m, off & 0xffff, DN_TO_IP_OUT, &args);
782 goto done;
783 }
784 #ifdef IPDIVERT
785 if (off != 0 && !(off & IP_FW_PORT_DYNT_FLAG)) {
786 struct mbuf *clone = NULL;
787
788 /* Clone packet if we're doing a 'tee' */
789 if ((off & IP_FW_PORT_TEE_FLAG))
790 clone = m_dup(m, MB_DONTWAIT);
791
792 /*
793 * XXX
794 * delayed checksums are not currently compatible
795 * with divert sockets.
796 */
797 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
798 in_delayed_cksum(m);
799 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
800 }
801
802 /* Restore packet header fields to original values */
803 ip->ip_len = htons(ip->ip_len);
804 ip->ip_off = htons(ip->ip_off);
805
806 /* Deliver packet to divert input routine */
807 divert_packet(m, 0, off & 0xffff);
808
809 /* If 'tee', continue with original packet */
810 if (clone != NULL) {
811 m = clone;
812 ip = mtod(m, struct ip *);
813 goto pass;
814 }
815 goto done;
816 }
817 #endif
818
819 /* IPFIREWALL_FORWARD */
820 /*
821 * Check dst to make sure it is directly reachable on the
822 * interface we previously thought it was.
823 * If it isn't (which may be likely in some situations) we have
824 * to re-route it (ie, find a route for the next-hop and the
825 * associated interface) and set them here. This is nested
826 * forwarding which in most cases is undesirable, except where
827 * such control is nigh impossible. So we do it here.
828 * And I'm babbling.
829 */
830 if (off == 0 && old != dst) { /* FORWARD, dst has changed */
831 #if 0
832 /*
833 * XXX To improve readability, this block should be
834 * changed into a function call as below:
835 */
836 error = ip_ipforward(&m, &dst, &ifp);
837 if (error)
838 goto bad;
839 if (m == NULL) /* ip_input consumed the mbuf */
840 goto done;
841 #else
842 struct in_ifaddr *ia;
843 struct in_ifaddr_container *iac;
844
845 /*
846 * XXX sro_fwd below is static, and a pointer
847 * to it gets passed to routines downstream.
848 * This could have surprisingly bad results in
849 * practice, because its content is overwritten
850 * by subsequent packets.
851 */
852 /* There must be a better way to do this next line... */
853 static struct route sro_fwd;
854 struct route *ro_fwd = &sro_fwd;
855
856 #if 0
857 print_ip("IPFIREWALL_FORWARD: New dst ip: ",
858 dst->sin_addr, "\n");
859 #endif
860
861 /*
862 * We need to figure out if we have been forwarded
863 * to a local socket. If so, then we should somehow
864 * "loop back" to ip_input, and get directed to the
865 * PCB as if we had received this packet. This is
866 * because it may be dificult to identify the packets
867 * you want to forward until they are being output
868 * and have selected an interface. (e.g. locally
869 * initiated packets) If we used the loopback inteface,
870 * we would not be able to control what happens
871 * as the packet runs through ip_input() as
872 * it is done through a ISR.
873 */
874 ia = NULL;
875 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr),
876 ia_hash) {
877 /*
878 * If the addr to forward to is one
879 * of ours, we pretend to
880 * be the destination for this packet.
881 */
882 if (IA_SIN(iac->ia)->sin_addr.s_addr ==
883 dst->sin_addr.s_addr) {
884 ia = iac->ia;
885 break;
886 }
887 }
888 if (ia != NULL) { /* tell ip_input "dont filter" */
889 struct m_hdr tag;
890
891 tag.mh_type = MT_TAG;
892 tag.mh_flags = PACKET_TAG_IPFORWARD;
893 tag.mh_data = (caddr_t)args.next_hop;
894 tag.mh_next = m;
895
896 if (m->m_pkthdr.rcvif == NULL)
897 m->m_pkthdr.rcvif = ifunit("lo0");
898 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
899 m->m_pkthdr.csum_flags |=
900 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
901 m->m_pkthdr.csum_data = 0xffff;
902 }
903 m->m_pkthdr.csum_flags |=
904 CSUM_IP_CHECKED | CSUM_IP_VALID;
905 ip->ip_len = htons(ip->ip_len);
906 ip->ip_off = htons(ip->ip_off);
907 ip_input((struct mbuf *)&tag);
908 goto done;
909 }
910 /* Some of the logic for this was nicked from above.
911 *
912 * This rewrites the cached route in a local PCB.
913 * Is this what we want to do?
914 */
915 bcopy(dst, &ro_fwd->ro_dst, sizeof *dst);
916 ro_fwd->ro_rt = NULL;
917
918 rtalloc_ign(ro_fwd, RTF_PRCLONING);
919 if (ro_fwd->ro_rt == NULL) {
920 ipstat.ips_noroute++;
921 error = EHOSTUNREACH;
922 goto bad;
923 }
924
925 ia = ifatoia(ro_fwd->ro_rt->rt_ifa);
926 ifp = ro_fwd->ro_rt->rt_ifp;
927 ro_fwd->ro_rt->rt_use++;
928 if (ro_fwd->ro_rt->rt_flags & RTF_GATEWAY)
929 dst = (struct sockaddr_in *)
930 ro_fwd->ro_rt->rt_gateway;
931 if (ro_fwd->ro_rt->rt_flags & RTF_HOST)
932 isbroadcast =
933 (ro_fwd->ro_rt->rt_flags & RTF_BROADCAST);
934 else
935 isbroadcast = in_broadcast(dst->sin_addr, ifp);
936 if (ro->ro_rt != NULL)
937 rtfree(ro->ro_rt);
938 ro->ro_rt = ro_fwd->ro_rt;
939 dst = (struct sockaddr_in *)&ro_fwd->ro_dst;
940
941 #endif /* ... block to be put into a function */
942 /*
943 * If we added a default src ip earlier,
944 * which would have been gotten from the-then
945 * interface, do it again, from the new one.
946 */
947 if (src_was_INADDR_ANY)
948 ip->ip_src = IA_SIN(ia)->sin_addr;
949 goto pass ;
950 }
951
952 /*
953 * if we get here, none of the above matches, and
954 * we have to drop the pkt
955 */
956 m_freem(m);
957 error = EACCES; /* not sure this is the right error msg */
958 goto done;
959 }
960
961 pass:
962 /* 127/8 must not appear on wire - RFC1122. */
963 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
964 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
965 if (!(ifp->if_flags & IFF_LOOPBACK)) {
966 ipstat.ips_badaddr++;
967 error = EADDRNOTAVAIL;
968 goto bad;
969 }
970 }
971
972 m->m_pkthdr.csum_flags |= CSUM_IP;
973 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
974 if (sw_csum & CSUM_DELAY_DATA) {
975 in_delayed_cksum(m);
976 sw_csum &= ~CSUM_DELAY_DATA;
977 }
978 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
979
980 /*
981 * If small enough for interface, or the interface will take
982 * care of the fragmentation for us, can just send directly.
983 */
984 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) &&
985 !(ip->ip_off & IP_DF))) {
986 ip->ip_len = htons(ip->ip_len);
987 ip->ip_off = htons(ip->ip_off);
988 ip->ip_sum = 0;
989 if (sw_csum & CSUM_DELAY_IP) {
990 if (ip->ip_vhl == IP_VHL_BORING) {
991 ip->ip_sum = in_cksum_hdr(ip);
992 } else {
993 ip->ip_sum = in_cksum(m, hlen);
994 }
995 }
996
997 /* Record statistics for this interface address. */
998 if (!(flags & IP_FORWARDING) && ia) {
999 ia->ia_ifa.if_opackets++;
1000 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1001 }
1002
1003 #ifdef IPSEC
1004 /* clean ipsec history once it goes out of the node */
1005 ipsec_delaux(m);
1006 #endif
1007
1008 #ifdef MBUF_STRESS_TEST
1009 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) {
1010 struct mbuf *m1, *m2;
1011 int length, tmp;
1012
1013 tmp = length = m->m_pkthdr.len;
1014
1015 while ((length -= mbuf_frag_size) >= 1) {
1016 m1 = m_split(m, length, MB_DONTWAIT);
1017 if (m1 == NULL)
1018 break;
1019 m2 = m;
1020 while (m2->m_next != NULL)
1021 m2 = m2->m_next;
1022 m2->m_next = m1;
1023 }
1024 m->m_pkthdr.len = tmp;
1025 }
1026 #endif
1027
1028 #ifdef MPLS
1029 struct rtentry *send_route = ro->ro_rt; /* copy-in/copy-out parameter */
1030
1031 if (!mpls_output_process(ifp, m, &dst, send_route))
1032 goto done;
1033 #endif
1034 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
1035 ro->ro_rt);
1036 goto done;
1037 }
1038
1039 if (ip->ip_off & IP_DF) {
1040 error = EMSGSIZE;
1041 /*
1042 * This case can happen if the user changed the MTU
1043 * of an interface after enabling IP on it. Because
1044 * most netifs don't keep track of routes pointing to
1045 * them, there is no way for one to update all its
1046 * routes when the MTU is changed.
1047 */
1048 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) &&
1049 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) &&
1050 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) {
1051 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
1052 }
1053 ipstat.ips_cantfrag++;
1054 goto bad;
1055 }
1056
1057 /*
1058 * Too large for interface; fragment if possible. If successful,
1059 * on return, m will point to a list of packets to be sent.
1060 */
1061 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum);
1062 if (error)
1063 goto bad;
1064 for (; m; m = m0) {
1065 m0 = m->m_nextpkt;
1066 m->m_nextpkt = NULL;
1067 #ifdef IPSEC
1068 /* clean ipsec history once it goes out of the node */
1069 ipsec_delaux(m);
1070 #endif
1071 if (error == 0) {
1072 /* Record statistics for this interface address. */
1073 if (ia != NULL) {
1074 ia->ia_ifa.if_opackets++;
1075 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1076 }
1077 #ifdef MPLS
1078 struct rtentry *send_route = ro->ro_rt; /* copy-in/copy-out parameter */
1079
1080 if (!mpls_output_process(ifp, m, &dst, send_route))
1081 goto done;
1082 #endif
1083 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
1084 ro->ro_rt);
1085 } else {
1086 m_freem(m);
1087 }
1088 }
1089
1090 if (error == 0)
1091 ipstat.ips_fragmented++;
1092
1093 done:
1094 if (ro == &iproute && ro->ro_rt != NULL) {
1095 RTFREE(ro->ro_rt);
1096 ro->ro_rt = NULL;
1097 }
1098 #ifdef IPSEC
1099 if (sp != NULL) {
1100 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1101 kprintf("DP ip_output call free SP:%p\n", sp));
1102 key_freesp(sp);
1103 }
1104 #endif
1105 #ifdef FAST_IPSEC
1106 if (sp != NULL)
1107 KEY_FREESP(&sp);
1108 #endif
1109 if (dn_mtag != NULL)
1110 m_tag_free(dn_mtag);
1111
1112 return (error);
1113 bad:
1114 m_freem(m);
1115 goto done;
1116 }
1117
1118 /*
1119 * Create a chain of fragments which fit the given mtu. m_frag points to the
1120 * mbuf to be fragmented; on return it points to the chain with the fragments.
1121 * Return 0 if no error. If error, m_frag may contain a partially built
1122 * chain of fragments that should be freed by the caller.
1123 *
1124 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
1125 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
1126 */
1127 int
1128 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
1129 u_long if_hwassist_flags, int sw_csum)
1130 {
1131 int error = 0;
1132 int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
1133 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
1134 int off;
1135 struct mbuf *m0 = *m_frag; /* the original packet */
1136 int firstlen;
1137 struct mbuf **mnext;
1138 int nfrags;
1139
1140 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */
1141 ipstat.ips_cantfrag++;
1142 return EMSGSIZE;
1143 }
1144
1145 /*
1146 * Must be able to put at least 8 bytes per fragment.
1147 */
1148 if (len < 8)
1149 return EMSGSIZE;
1150
1151 /*
1152 * If the interface will not calculate checksums on
1153 * fragmented packets, then do it here.
1154 */
1155 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) &&
1156 !(if_hwassist_flags & CSUM_IP_FRAGS)) {
1157 in_delayed_cksum(m0);
1158 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1159 }
1160
1161 if (len > PAGE_SIZE) {
1162 /*
1163 * Fragment large datagrams such that each segment
1164 * contains a multiple of PAGE_SIZE amount of data,
1165 * plus headers. This enables a receiver to perform
1166 * page-flipping zero-copy optimizations.
1167 *
1168 * XXX When does this help given that sender and receiver
1169 * could have different page sizes, and also mtu could
1170 * be less than the receiver's page size ?
1171 */
1172 int newlen;
1173 struct mbuf *m;
1174
1175 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next)
1176 off += m->m_len;
1177
1178 /*
1179 * firstlen (off - hlen) must be aligned on an
1180 * 8-byte boundary
1181 */
1182 if (off < hlen)
1183 goto smart_frag_failure;
1184 off = ((off - hlen) & ~7) + hlen;
1185 newlen = (~PAGE_MASK) & mtu;
1186 if ((newlen + sizeof(struct ip)) > mtu) {
1187 /* we failed, go back the default */
1188 smart_frag_failure:
1189 newlen = len;
1190 off = hlen + len;
1191 }
1192 len = newlen;
1193
1194 } else {
1195 off = hlen + len;
1196 }
1197
1198 firstlen = off - hlen;
1199 mnext = &m0->m_nextpkt; /* pointer to next packet */
1200
1201 /*
1202 * Loop through length of segment after first fragment,
1203 * make new header and copy data of each part and link onto chain.
1204 * Here, m0 is the original packet, m is the fragment being created.
1205 * The fragments are linked off the m_nextpkt of the original
1206 * packet, which after processing serves as the first fragment.
1207 */
1208 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) {
1209 struct ip *mhip; /* ip header on the fragment */
1210 struct mbuf *m;
1211 int mhlen = sizeof(struct ip);
1212
1213 MGETHDR(m, MB_DONTWAIT, MT_HEADER);
1214 if (m == NULL) {
1215 error = ENOBUFS;
1216 ipstat.ips_odropped++;
1217 goto done;
1218 }
1219 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
1220 /*
1221 * In the first mbuf, leave room for the link header, then
1222 * copy the original IP header including options. The payload
1223 * goes into an additional mbuf chain returned by m_copy().
1224 */
1225 m->m_data += max_linkhdr;
1226 mhip = mtod(m, struct ip *);
1227 *mhip = *ip;
1228 if (hlen > sizeof(struct ip)) {
1229 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip);
1230 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2);
1231 }
1232 m->m_len = mhlen;
1233 /* XXX do we need to add ip->ip_off below ? */
1234 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
1235 if (off + len >= ip->ip_len) { /* last fragment */
1236 len = ip->ip_len - off;
1237 m->m_flags |= M_LASTFRAG;
1238 } else
1239 mhip->ip_off |= IP_MF;
1240 mhip->ip_len = htons((u_short)(len + mhlen));
1241 m->m_next = m_copy(m0, off, len);
1242 if (m->m_next == NULL) { /* copy failed */
1243 m_free(m);
1244 error = ENOBUFS; /* ??? */
1245 ipstat.ips_odropped++;
1246 goto done;
1247 }
1248 m->m_pkthdr.len = mhlen + len;
1249 m->m_pkthdr.rcvif = (struct ifnet *)NULL;
1250 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
1251 mhip->ip_off = htons(mhip->ip_off);
1252 mhip->ip_sum = 0;
1253 if (sw_csum & CSUM_DELAY_IP)
1254 mhip->ip_sum = in_cksum(m, mhlen);
1255 *mnext = m;
1256 mnext = &m->m_nextpkt;
1257 }
1258 ipstat.ips_ofragments += nfrags;
1259
1260 /* set first marker for fragment chain */
1261 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1262 m0->m_pkthdr.csum_data = nfrags;
1263
1264 /*
1265 * Update first fragment by trimming what's been copied out
1266 * and updating header.
1267 */
1268 m_adj(m0, hlen + firstlen - ip->ip_len);
1269 m0->m_pkthdr.len = hlen + firstlen;
1270 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1271 ip->ip_off |= IP_MF;
1272 ip->ip_off = htons(ip->ip_off);
1273 ip->ip_sum = 0;
1274 if (sw_csum & CSUM_DELAY_IP)
1275 ip->ip_sum = in_cksum(m0, hlen);
1276
1277 done:
1278 *m_frag = m0;
1279 return error;
1280 }
1281
1282 void
1283 in_delayed_cksum(struct mbuf *m)
1284 {
1285 struct ip *ip;
1286 u_short csum, offset;
1287
1288 ip = mtod(m, struct ip *);
1289 offset = IP_VHL_HL(ip->ip_vhl) << 2 ;
1290 csum = in_cksum_skip(m, ip->ip_len, offset);
1291 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
1292 csum = 0xffff;
1293 offset += m->m_pkthdr.csum_data; /* checksum offset */
1294
1295 if (offset + sizeof(u_short) > m->m_len) {
1296 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n",
1297 m->m_len, offset, ip->ip_p);
1298 /*
1299 * XXX
1300 * this shouldn't happen, but if it does, the
1301 * correct behavior may be to insert the checksum
1302 * in the existing chain instead of rearranging it.
1303 */
1304 m = m_pullup(m, offset + sizeof(u_short));
1305 }
1306 *(u_short *)(m->m_data + offset) = csum;
1307 }
1308
1309 /*
1310 * Insert IP options into preformed packet.
1311 * Adjust IP destination as required for IP source routing,
1312 * as indicated by a non-zero in_addr at the start of the options.
1313 *
1314 * XXX This routine assumes that the packet has no options in place.
1315 */
1316 static struct mbuf *
1317 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen)
1318 {
1319 struct ipoption *p = mtod(opt, struct ipoption *);
1320 struct mbuf *n;
1321 struct ip *ip = mtod(m, struct ip *);
1322 unsigned optlen;
1323
1324 optlen = opt->m_len - sizeof p->ipopt_dst;
1325 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) {
1326 *phlen = 0;
1327 return (m); /* XXX should fail */
1328 }
1329 if (p->ipopt_dst.s_addr)
1330 ip->ip_dst = p->ipopt_dst;
1331 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
1332 MGETHDR(n, MB_DONTWAIT, MT_HEADER);
1333 if (n == NULL) {
1334 *phlen = 0;
1335 return (m);
1336 }
1337 n->m_pkthdr.rcvif = (struct ifnet *)NULL;
1338 n->m_pkthdr.len = m->m_pkthdr.len + optlen;
1339 m->m_len -= sizeof(struct ip);
1340 m->m_data += sizeof(struct ip);
1341 n->m_next = m;
1342 m = n;
1343 m->m_len = optlen + sizeof(struct ip);
1344 m->m_data += max_linkhdr;
1345 memcpy(mtod(m, void *), ip, sizeof(struct ip));
1346 } else {
1347 m->m_data -= optlen;
1348 m->m_len += optlen;
1349 m->m_pkthdr.len += optlen;
1350 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip));
1351 }
1352 ip = mtod(m, struct ip *);
1353 bcopy(p->ipopt_list, ip + 1, optlen);
1354 *phlen = sizeof(struct ip) + optlen;
1355 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2);
1356 ip->ip_len += optlen;
1357 return (m);
1358 }
1359
1360 /*
1361 * Copy options from ip to jp,
1362 * omitting those not copied during fragmentation.
1363 */
1364 int
1365 ip_optcopy(struct ip *ip, struct ip *jp)
1366 {
1367 u_char *cp, *dp;
1368 int opt, optlen, cnt;
1369
1370 cp = (u_char *)(ip + 1);
1371 dp = (u_char *)(jp + 1);
1372 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
1373 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1374 opt = cp[0];
1375 if (opt == IPOPT_EOL)
1376 break;
1377 if (opt == IPOPT_NOP) {
1378 /* Preserve for IP mcast tunnel's LSRR alignment. */
1379 *dp++ = IPOPT_NOP;
1380 optlen = 1;
1381 continue;
1382 }
1383
1384 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp,
1385 ("ip_optcopy: malformed ipv4 option"));
1386 optlen = cp[IPOPT_OLEN];
1387 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt,
1388 ("ip_optcopy: malformed ipv4 option"));
1389
1390 /* bogus lengths should have been caught by ip_dooptions */
1391 if (optlen > cnt)
1392 optlen = cnt;
1393 if (IPOPT_COPIED(opt)) {
1394 bcopy(cp, dp, optlen);
1395 dp += optlen;
1396 }
1397 }
1398 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
1399 *dp++ = IPOPT_EOL;
1400 return (optlen);
1401 }
1402
1403 /*
1404 * IP socket option processing.
1405 */
1406 int
1407 ip_ctloutput(struct socket *so, struct sockopt *sopt)
1408 {
1409 struct inpcb *inp = so->so_pcb;
1410 int error, optval;
1411
1412 error = optval = 0;
1413 if (sopt->sopt_level != IPPROTO_IP) {
1414 return (EINVAL);
1415 }
1416
1417 switch (sopt->sopt_dir) {
1418 case SOPT_SET:
1419 switch (sopt->sopt_name) {
1420 case IP_OPTIONS:
1421 #ifdef notyet
1422 case IP_RETOPTS:
1423 #endif
1424 {
1425 struct mbuf *m;
1426 if (sopt->sopt_valsize > MLEN) {
1427 error = EMSGSIZE;
1428 break;
1429 }
1430 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER);
1431 if (m == NULL) {
1432 error = ENOBUFS;
1433 break;
1434 }
1435 m->m_len = sopt->sopt_valsize;
1436 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len,
1437 m->m_len);
1438 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options,
1439 m));
1440 }
1441
1442 case IP_TOS:
1443 case IP_TTL:
1444 case IP_MINTTL:
1445 case IP_RECVOPTS:
1446 case IP_RECVRETOPTS:
1447 case IP_RECVDSTADDR:
1448 case IP_RECVIF:
1449 case IP_RECVTTL:
1450 case IP_FAITH:
1451 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1452 sizeof optval);
1453 if (error)
1454 break;
1455 switch (sopt->sopt_name) {
1456 case IP_TOS:
1457 inp->inp_ip_tos = optval;
1458 break;
1459
1460 case IP_TTL:
1461 inp->inp_ip_ttl = optval;
1462 break;
1463 case IP_MINTTL:
1464 if (optval > 0 && optval <= MAXTTL)
1465 inp->inp_ip_minttl = optval;
1466 else
1467 error = EINVAL;
1468 break;
1469 #define OPTSET(bit) \
1470 if (optval) \
1471 inp->inp_flags |= bit; \
1472 else \
1473 inp->inp_flags &= ~bit;
1474
1475 case IP_RECVOPTS:
1476 OPTSET(INP_RECVOPTS);
1477 break;
1478
1479 case IP_RECVRETOPTS:
1480 OPTSET(INP_RECVRETOPTS);
1481 break;
1482
1483 case IP_RECVDSTADDR:
1484 OPTSET(INP_RECVDSTADDR);
1485 break;
1486
1487 case IP_RECVIF:
1488 OPTSET(INP_RECVIF);
1489 break;
1490
1491 case IP_RECVTTL:
1492 OPTSET(INP_RECVTTL);
1493 break;
1494
1495 case IP_FAITH:
1496 OPTSET(INP_FAITH);
1497 break;
1498 }
1499 break;
1500 #undef OPTSET
1501
1502 case IP_MULTICAST_IF:
1503 case IP_MULTICAST_VIF:
1504 case IP_MULTICAST_TTL:
1505 case IP_MULTICAST_LOOP:
1506 case IP_ADD_MEMBERSHIP:
1507 case IP_DROP_MEMBERSHIP:
1508 error = ip_setmoptions(sopt, &inp->inp_moptions);
1509 break;
1510
1511 case IP_PORTRANGE:
1512 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1513 sizeof optval);
1514 if (error)
1515 break;
1516
1517 switch (optval) {
1518 case IP_PORTRANGE_DEFAULT:
1519 inp->inp_flags &= ~(INP_LOWPORT);
1520 inp->inp_flags &= ~(INP_HIGHPORT);
1521 break;
1522
1523 case IP_PORTRANGE_HIGH:
1524 inp->inp_flags &= ~(INP_LOWPORT);
1525 inp->inp_flags |= INP_HIGHPORT;
1526 break;
1527
1528 case IP_PORTRANGE_LOW:
1529 inp->inp_flags &= ~(INP_HIGHPORT);
1530 inp->inp_flags |= INP_LOWPORT;
1531 break;
1532
1533 default:
1534 error = EINVAL;
1535 break;
1536 }
1537 break;
1538
1539 #if defined(IPSEC) || defined(FAST_IPSEC)
1540 case IP_IPSEC_POLICY:
1541 {
1542 caddr_t req;
1543 size_t len = 0;
1544 int priv;
1545 struct mbuf *m;
1546 int optname;
1547
1548 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1549 break;
1550 soopt_to_mbuf(sopt, m);
1551 priv = (sopt->sopt_td != NULL &&
1552 suser(sopt->sopt_td) != 0) ? 0 : 1;
1553 req = mtod(m, caddr_t);
1554 len = m->m_len;
1555 optname = sopt->sopt_name;
1556 error = ipsec4_set_policy(inp, optname, req, len, priv);
1557 m_freem(m);
1558 break;
1559 }
1560 #endif /*IPSEC*/
1561
1562 default:
1563 error = ENOPROTOOPT;
1564 break;
1565 }
1566 break;
1567
1568 case SOPT_GET:
1569 switch (sopt->sopt_name) {
1570 case IP_OPTIONS:
1571 case IP_RETOPTS:
1572 if (inp->inp_options)
1573 soopt_from_kbuf(sopt, mtod(inp->inp_options,
1574 char *),
1575 inp->inp_options->m_len);
1576 else
1577 sopt->sopt_valsize = 0;
1578 break;
1579
1580 case IP_TOS:
1581 case IP_TTL:
1582 case IP_MINTTL:
1583 case IP_RECVOPTS:
1584 case IP_RECVRETOPTS:
1585 case IP_RECVDSTADDR:
1586 case IP_RECVTTL:
1587 case IP_RECVIF:
1588 case IP_PORTRANGE:
1589 case IP_FAITH:
1590 switch (sopt->sopt_name) {
1591
1592 case IP_TOS:
1593 optval = inp->inp_ip_tos;
1594 break;
1595
1596 case IP_TTL:
1597 optval = inp->inp_ip_ttl;
1598 break;
1599 case IP_MINTTL:
1600 optval = inp->inp_ip_minttl;
1601 break;
1602
1603 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1604
1605 case IP_RECVOPTS:
1606 optval = OPTBIT(INP_RECVOPTS);
1607 break;
1608
1609 case IP_RECVRETOPTS:
1610 optval = OPTBIT(INP_RECVRETOPTS);
1611 break;
1612
1613 case IP_RECVDSTADDR:
1614 optval = OPTBIT(INP_RECVDSTADDR);
1615 break;
1616
1617 case IP_RECVTTL:
1618 optval = OPTBIT(INP_RECVTTL);
1619 break;
1620
1621 case IP_RECVIF:
1622 optval = OPTBIT(INP_RECVIF);
1623 break;
1624
1625 case IP_PORTRANGE:
1626 if (inp->inp_flags & INP_HIGHPORT)
1627 optval = IP_PORTRANGE_HIGH;
1628 else if (inp->inp_flags & INP_LOWPORT)
1629 optval = IP_PORTRANGE_LOW;
1630 else
1631 optval = 0;
1632 break;
1633
1634 case IP_FAITH:
1635 optval = OPTBIT(INP_FAITH);
1636 break;
1637 }
1638 soopt_from_kbuf(sopt, &optval, sizeof optval);
1639 break;
1640
1641 case IP_MULTICAST_IF:
1642 case IP_MULTICAST_VIF:
1643 case IP_MULTICAST_TTL:
1644 case IP_MULTICAST_LOOP:
1645 case IP_ADD_MEMBERSHIP:
1646 case IP_DROP_MEMBERSHIP:
1647 error = ip_getmoptions(sopt, inp->inp_moptions);
1648 break;
1649
1650 #if defined(IPSEC) || defined(FAST_IPSEC)
1651 case IP_IPSEC_POLICY:
1652 {
1653 struct mbuf *m = NULL;
1654 caddr_t req = NULL;
1655 size_t len = 0;
1656
1657 if (m != NULL) {
1658 req = mtod(m, caddr_t);
1659 len = m->m_len;
1660 }
1661 error = ipsec4_get_policy(so->so_pcb, req, len, &m);
1662 if (error == 0)
1663 error = soopt_from_mbuf(sopt, m); /* XXX */
1664 if (error == 0)
1665 m_freem(m);
1666 break;
1667 }
1668 #endif /*IPSEC*/
1669
1670 default:
1671 error = ENOPROTOOPT;
1672 break;
1673 }
1674 break;
1675 }
1676 return (error);
1677 }
1678
1679 /*
1680 * Set up IP options in pcb for insertion in output packets.
1681 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1682 * with destination address if source routed.
1683 */
1684 static int
1685 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m)
1686 {
1687 int cnt, optlen;
1688 u_char *cp;
1689 u_char opt;
1690
1691 /* turn off any old options */
1692 if (*pcbopt)
1693 m_free(*pcbopt);
1694 *pcbopt = 0;
1695 if (m == NULL || m->m_len == 0) {
1696 /*
1697 * Only turning off any previous options.
1698 */
1699 if (m != NULL)
1700 m_free(m);
1701 return (0);
1702 }
1703
1704 if (m->m_len % sizeof(int32_t))
1705 goto bad;
1706 /*
1707 * IP first-hop destination address will be stored before
1708 * actual options; move other options back
1709 * and clear it when none present.
1710 */
1711 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
1712 goto bad;
1713 cnt = m->m_len;
1714 m->m_len += sizeof(struct in_addr);
1715 cp = mtod(m, u_char *) + sizeof(struct in_addr);
1716 ovbcopy(mtod(m, caddr_t), cp, cnt);
1717 bzero(mtod(m, caddr_t), sizeof(struct in_addr));
1718
1719 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1720 opt = cp[IPOPT_OPTVAL];
1721 if (opt == IPOPT_EOL)
1722 break;
1723 if (opt == IPOPT_NOP)
1724 optlen = 1;
1725 else {
1726 if (cnt < IPOPT_OLEN + sizeof *cp)
1727 goto bad;
1728 optlen = cp[IPOPT_OLEN];
1729 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt)
1730 goto bad;
1731 }
1732 switch (opt) {
1733
1734 default:
1735 break;
1736
1737 case IPOPT_LSRR:
1738 case IPOPT_SSRR:
1739 /*
1740 * user process specifies route as:
1741 * ->A->B->C->D
1742 * D must be our final destination (but we can't
1743 * check that since we may not have connected yet).
1744 * A is first hop destination, which doesn't appear in
1745 * actual IP option, but is stored before the options.
1746 */
1747 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
1748 goto bad;
1749 m->m_len -= sizeof(struct in_addr);
1750 cnt -= sizeof(struct in_addr);
1751 optlen -= sizeof(struct in_addr);
1752 cp[IPOPT_OLEN] = optlen;
1753 /*
1754 * Move first hop before start of options.
1755 */
1756 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
1757 sizeof(struct in_addr));
1758 /*
1759 * Then copy rest of options back
1760 * to close up the deleted entry.
1761 */
1762 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr),
1763 &cp[IPOPT_OFFSET+1],
1764 cnt - (IPOPT_MINOFF - 1));
1765 break;
1766 }
1767 }
1768 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
1769 goto bad;
1770 *pcbopt = m;
1771 return (0);
1772
1773 bad:
1774 m_free(m);
1775 return (EINVAL);
1776 }
1777
1778 /*
1779 * XXX
1780 * The whole multicast option thing needs to be re-thought.
1781 * Several of these options are equally applicable to non-multicast
1782 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1783 * standard option (IP_TTL).
1784 */
1785
1786 /*
1787 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1788 */
1789 static struct ifnet *
1790 ip_multicast_if(struct in_addr *a, int *ifindexp)
1791 {
1792 int ifindex;
1793 struct ifnet *ifp;
1794
1795 if (ifindexp)
1796 *ifindexp = 0;
1797 if (ntohl(a->s_addr) >> 24 == 0) {
1798 ifindex = ntohl(a->s_addr) & 0xffffff;
1799 if (ifindex < 0 || if_index < ifindex)
1800 return NULL;
1801 ifp = ifindex2ifnet[ifindex];
1802 if (ifindexp)
1803 *ifindexp = ifindex;
1804 } else {
1805 ifp = INADDR_TO_IFP(a);
1806 }
1807 return ifp;
1808 }
1809
1810 /*
1811 * Set the IP multicast options in response to user setsockopt().
1812 */
1813 static int
1814 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop)
1815 {
1816 int error = 0;
1817 int i;
1818 struct in_addr addr;
1819 struct ip_mreq mreq;
1820 struct ifnet *ifp;
1821 struct ip_moptions *imo = *imop;
1822 int ifindex;
1823
1824 if (imo == NULL) {
1825 /*
1826 * No multicast option buffer attached to the pcb;
1827 * allocate one and initialize to default values.
1828 */
1829 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK);
1830
1831 *imop = imo;
1832 imo->imo_multicast_ifp = NULL;
1833 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1834 imo->imo_multicast_vif = -1;
1835 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1836 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
1837 imo->imo_num_memberships = 0;
1838 }
1839 switch (sopt->sopt_name) {
1840 /* store an index number for the vif you wanna use in the send */
1841 case IP_MULTICAST_VIF:
1842 if (legal_vif_num == 0) {
1843 error = EOPNOTSUPP;
1844 break;
1845 }
1846 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i);
1847 if (error)
1848 break;
1849 if (!legal_vif_num(i) && (i != -1)) {
1850 error = EINVAL;
1851 break;
1852 }
1853 imo->imo_multicast_vif = i;
1854 break;
1855
1856 case IP_MULTICAST_IF:
1857 /*
1858 * Select the interface for outgoing multicast packets.
1859 */
1860 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr);
1861 if (error)
1862 break;
1863
1864 /*
1865 * INADDR_ANY is used to remove a previous selection.
1866 * When no interface is selected, a default one is
1867 * chosen every time a multicast packet is sent.
1868 */
1869 if (addr.s_addr == INADDR_ANY) {
1870 imo->imo_multicast_ifp = NULL;
1871 break;
1872 }
1873 /*
1874 * The selected interface is identified by its local
1875 * IP address. Find the interface and confirm that
1876 * it supports multicasting.
1877 */
1878 crit_enter();
1879 ifp = ip_multicast_if(&addr, &ifindex);
1880 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1881 crit_exit();
1882 error = EADDRNOTAVAIL;
1883 break;
1884 }
1885 imo->imo_multicast_ifp = ifp;
1886 if (ifindex)
1887 imo->imo_multicast_addr = addr;
1888 else
1889 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1890 crit_exit();
1891 break;
1892
1893 case IP_MULTICAST_TTL:
1894 /*
1895 * Set the IP time-to-live for outgoing multicast packets.
1896 * The original multicast API required a char argument,
1897 * which is inconsistent with the rest of the socket API.
1898 * We allow either a char or an int.
1899 */
1900 if (sopt->sopt_valsize == 1) {
1901 u_char ttl;
1902 error = soopt_to_kbuf(sopt, &ttl, 1, 1);
1903 if (error)
1904 break;
1905 imo->imo_multicast_ttl = ttl;
1906 } else {
1907 u_int ttl;
1908 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl);
1909 if (error)
1910 break;
1911 if (ttl > 255)
1912 error = EINVAL;
1913 else
1914 imo->imo_multicast_ttl = ttl;
1915 }
1916 break;
1917
1918 case IP_MULTICAST_LOOP:
1919 /*
1920 * Set the loopback flag for outgoing multicast packets.
1921 * Must be zero or one. The original multicast API required a
1922 * char argument, which is inconsistent with the rest
1923 * of the socket API. We allow either a char or an int.
1924 */
1925 if (sopt->sopt_valsize == 1) {
1926 u_char loop;
1927
1928 error = soopt_to_kbuf(sopt, &loop, 1, 1);
1929 if (error)
1930 break;
1931 imo->imo_multicast_loop = !!loop;
1932 } else {
1933 u_int loop;
1934
1935 error = soopt_to_kbuf(sopt, &loop, sizeof loop,
1936 sizeof loop);
1937 if (error)
1938 break;
1939 imo->imo_multicast_loop = !!loop;
1940 }
1941 break;
1942
1943 case IP_ADD_MEMBERSHIP:
1944 /*
1945 * Add a multicast group membership.
1946 * Group must be a valid IP multicast address.
1947 */
1948 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1949 if (error)
1950 break;
1951
1952 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1953 error = EINVAL;
1954 break;
1955 }
1956 crit_enter();
1957 /*
1958 * If no interface address was provided, use the interface of
1959 * the route to the given multicast address.
1960 */
1961 if (mreq.imr_interface.s_addr == INADDR_ANY) {
1962 struct sockaddr_in dst;
1963 struct rtentry *rt;
1964
1965 bzero(&dst, sizeof(struct sockaddr_in));
1966 dst.sin_len = sizeof(struct sockaddr_in);
1967 dst.sin_family = AF_INET;
1968 dst.sin_addr = mreq.imr_multiaddr;
1969 rt = rtlookup((struct sockaddr *)&dst);
1970 if (rt == NULL) {
1971 error = EADDRNOTAVAIL;
1972 crit_exit();
1973 break;
1974 }
1975 --rt->rt_refcnt;
1976 ifp = rt->rt_ifp;
1977 } else {
1978 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1979 }
1980
1981 /*
1982 * See if we found an interface, and confirm that it
1983 * supports multicast.
1984 */
1985 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1986 error = EADDRNOTAVAIL;
1987 crit_exit();
1988 break;
1989 }
1990 /*
1991 * See if the membership already exists or if all the
1992 * membership slots are full.
1993 */
1994 for (i = 0; i < imo->imo_num_memberships; ++i) {
1995 if (imo->imo_membership[i]->inm_ifp == ifp &&
1996 imo->imo_membership[i]->inm_addr.s_addr
1997 == mreq.imr_multiaddr.s_addr)
1998 break;
1999 }
2000 if (i < imo->imo_num_memberships) {
2001 error = EADDRINUSE;
2002 crit_exit();
2003 break;
2004 }
2005 if (i == IP_MAX_MEMBERSHIPS) {
2006 error = ETOOMANYREFS;
2007 crit_exit();
2008 break;
2009 }
2010 /*
2011 * Everything looks good; add a new record to the multicast
2012 * address list for the given interface.
2013 */
2014 if ((imo->imo_membership[i] =
2015 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) {
2016 error = ENOBUFS;
2017 crit_exit();
2018 break;
2019 }
2020 ++imo->imo_num_memberships;
2021 crit_exit();
2022 break;
2023
2024 case IP_DROP_MEMBERSHIP:
2025 /*
2026 * Drop a multicast group membership.
2027 * Group must be a valid IP multicast address.
2028 */
2029 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
2030 if (error)
2031 break;
2032
2033 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
2034 error = EINVAL;
2035 break;
2036 }
2037
2038 crit_enter();
2039 /*
2040 * If an interface address was specified, get a pointer
2041 * to its ifnet structure.
2042 */
2043 if (mreq.imr_interface.s_addr == INADDR_ANY)
2044 ifp = NULL;
2045 else {
2046 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
2047 if (ifp == NULL) {
2048 error = EADDRNOTAVAIL;
2049 crit_exit();
2050 break;
2051 }
2052 }
2053 /*
2054 * Find the membership in the membership array.
2055 */
2056 for (i = 0; i < imo->imo_num_memberships; ++i) {
2057 if ((ifp == NULL ||
2058 imo->imo_membership[i]->inm_ifp == ifp) &&
2059 imo->imo_membership[i]->inm_addr.s_addr ==
2060 mreq.imr_multiaddr.s_addr)
2061 break;
2062 }
2063 if (i == imo->imo_num_memberships) {
2064 error = EADDRNOTAVAIL;
2065 crit_exit();
2066 break;
2067 }
2068 /*
2069 * Give up the multicast address record to which the
2070 * membership points.
2071 */
2072 in_delmulti(imo->imo_membership[i]);
2073 /*
2074 * Remove the gap in the membership array.
2075 */
2076 for (++i; i < imo->imo_num_memberships; ++i)
2077 imo->imo_membership[i-1] = imo->imo_membership[i];
2078 --imo->imo_num_memberships;
2079 crit_exit();
2080 break;
2081
2082 default:
2083 error = EOPNOTSUPP;
2084 break;
2085 }
2086
2087 /*
2088 * If all options have default values, no need to keep the mbuf.
2089 */
2090 if (imo->imo_multicast_ifp == NULL &&
2091 imo->imo_multicast_vif == -1 &&
2092 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
2093 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
2094 imo->imo_num_memberships == 0) {
2095 kfree(*imop, M_IPMOPTS);
2096 *imop = NULL;
2097 }
2098
2099 return (error);
2100 }
2101
2102 /*
2103 * Return the IP multicast options in response to user getsockopt().
2104 */
2105 static int
2106 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo)
2107 {
2108 struct in_addr addr;
2109 struct in_ifaddr *ia;
2110 int error, optval;
2111 u_char coptval;
2112
2113 error = 0;
2114 switch (sopt->sopt_name) {
2115 case IP_MULTICAST_VIF:
2116 if (imo != NULL)
2117 optval = imo->imo_multicast_vif;
2118 else
2119 optval = -1;
2120 soopt_from_kbuf(sopt, &optval, sizeof optval);
2121 break;
2122
2123 case IP_MULTICAST_IF:
2124 if (imo == NULL || imo->imo_multicast_ifp == NULL)
2125 addr.s_addr = INADDR_ANY;
2126 else if (imo->imo_multicast_addr.s_addr) {
2127 /* return the value user has set */
2128 addr = imo->imo_multicast_addr;
2129 } else {
2130 ia = IFP_TO_IA(imo->imo_multicast_ifp);
2131 addr.s_addr = (ia == NULL) ? INADDR_ANY
2132 : IA_SIN(ia)->sin_addr.s_addr;
2133 }
2134 soopt_from_kbuf(sopt, &addr, sizeof addr);
2135 break;
2136
2137 case IP_MULTICAST_TTL:
2138 if (imo == NULL)
2139 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
2140 else
2141 optval = coptval = imo->imo_multicast_ttl;
2142 if (sopt->sopt_valsize == 1)
2143 soopt_from_kbuf(sopt, &coptval, 1);
2144 else
2145 soopt_from_kbuf(sopt, &optval, sizeof optval);
2146 break;
2147
2148 case IP_MULTICAST_LOOP:
2149 if (imo == NULL)
2150 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
2151 else
2152 optval = coptval = imo->imo_multicast_loop;
2153 if (sopt->sopt_valsize == 1)
2154 soopt_from_kbuf(sopt, &coptval, 1);
2155 else
2156 soopt_from_kbuf(sopt, &optval, sizeof optval);
2157 break;
2158
2159 default:
2160 error = ENOPROTOOPT;
2161 break;
2162 }
2163 return (error);
2164 }
2165
2166 /*
2167 * Discard the IP multicast options.
2168 */
2169 void
2170 ip_freemoptions(struct ip_moptions *imo)
2171 {
2172 int i;
2173
2174 if (imo != NULL) {
2175 for (i = 0; i < imo->imo_num_memberships; ++i)
2176 in_delmulti(imo->imo_membership[i]);
2177 kfree(imo, M_IPMOPTS);
2178 }
2179 }
2180
2181 /*
2182 * Routine called from ip_output() to loop back a copy of an IP multicast
2183 * packet to the input queue of a specified interface. Note that this
2184 * calls the output routine of the loopback "driver", but with an interface
2185 * pointer that might NOT be a loopback interface -- evil, but easier than
2186 * replicating that code here.
2187 */
2188 static void
2189 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst,
2190 int hlen)
2191 {
2192 struct ip *ip;
2193 struct mbuf *copym;
2194
2195 copym = m_copypacket(m, MB_DONTWAIT);
2196 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
2197 copym = m_pullup(copym, hlen);
2198 if (copym != NULL) {
2199 /*
2200 * if the checksum hasn't been computed, mark it as valid
2201 */
2202 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2203 in_delayed_cksum(copym);
2204 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
2205 copym->m_pkthdr.csum_flags |=
2206 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2207 copym->m_pkthdr.csum_data = 0xffff;
2208 }
2209 /*
2210 * We don't bother to fragment if the IP length is greater
2211 * than the interface's MTU. Can this possibly matter?
2212 */
2213 ip = mtod(copym, struct ip *);
2214 ip->ip_len = htons(ip->ip_len);
2215 ip->ip_off = htons(ip->ip_off);
2216 ip->ip_sum = 0;
2217 if (ip->ip_vhl == IP_VHL_BORING) {
2218 ip->ip_sum = in_cksum_hdr(ip);
2219 } else {
2220 ip->ip_sum = in_cksum(copym, hlen);
2221 }
2222 /*
2223 * NB:
2224 * It's not clear whether there are any lingering
2225 * reentrancy problems in other areas which might
2226 * be exposed by using ip_input directly (in
2227 * particular, everything which modifies the packet
2228 * in-place). Yet another option is using the
2229 * protosw directly to deliver the looped back
2230 * packet. For the moment, we'll err on the side
2231 * of safety by using if_simloop().
2232 */
2233 #if 1 /* XXX */
2234 if (dst->sin_family != AF_INET) {
2235 kprintf("ip_mloopback: bad address family %d\n",
2236 dst->sin_family);
2237 dst->sin_family = AF_INET;
2238 }
2239 #endif
2240
2241 #ifdef notdef
2242 copym->m_pkthdr.rcvif = ifp;
2243 ip_input(copym);
2244 #else
2245 if_simloop(ifp, copym, dst->sin_family, 0);
2246 #endif
2247 }
2248 }
DragonFly BSD