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Actually hook powernow.4 into the build.
[dragonfly.git] / sys / netinet / ip_output.c
blobc6d7995b416148f04a67adbf39b9d6a4aabbbeea
1 /*
2 * Copyright (c) 1982, 1986, 1988, 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)ip_output.c 8.3 (Berkeley) 1/21/94
30 * $FreeBSD: src/sys/netinet/ip_output.c,v 1.99.2.37 2003/04/15 06:44:45 silby Exp $
31 * $DragonFly: src/sys/netinet/ip_output.c,v 1.67 2008/10/28 03:07:28 sephe Exp $
32 */
33
34 #define _IP_VHL
35
36 #include "opt_ipfw.h"
37 #include "opt_ipdn.h"
38 #include "opt_ipdivert.h"
39 #include "opt_ipfilter.h"
40 #include "opt_ipsec.h"
41 #include "opt_mbuf_stress_test.h"
42 #include "opt_mpls.h"
43
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/malloc.h>
48 #include <sys/mbuf.h>
49 #include <sys/protosw.h>
50 #include <sys/socket.h>
51 #include <sys/socketvar.h>
52 #include <sys/proc.h>
53 #include <sys/priv.h>
54 #include <sys/sysctl.h>
55 #include <sys/in_cksum.h>
56 #include <sys/lock.h>
57
58 #include <sys/thread2.h>
59 #include <sys/mplock2.h>
60
61 #include <net/if.h>
62 #include <net/netisr.h>
63 #include <net/pfil.h>
64 #include <net/route.h>
65
66 #include <netinet/in.h>
67 #include <netinet/in_systm.h>
68 #include <netinet/ip.h>
69 #include <netinet/in_pcb.h>
70 #include <netinet/in_var.h>
71 #include <netinet/ip_var.h>
72
73 #include <netproto/mpls/mpls_var.h>
74
75 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options");
76
77 #ifdef IPSEC
78 #include <netinet6/ipsec.h>
79 #include <netproto/key/key.h>
80 #ifdef IPSEC_DEBUG
81 #include <netproto/key/key_debug.h>
82 #else
83 #define KEYDEBUG(lev,arg)
84 #endif
85 #endif /*IPSEC*/
86
87 #ifdef FAST_IPSEC
88 #include <netproto/ipsec/ipsec.h>
89 #include <netproto/ipsec/xform.h>
90 #include <netproto/ipsec/key.h>
91 #endif /*FAST_IPSEC*/
92
93 #include <net/ipfw/ip_fw.h>
94 #include <net/dummynet/ip_dummynet.h>
95
96 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\
97 x, (ntohl(a.s_addr)>>24)&0xFF,\
98 (ntohl(a.s_addr)>>16)&0xFF,\
99 (ntohl(a.s_addr)>>8)&0xFF,\
100 (ntohl(a.s_addr))&0xFF, y);
101
102 u_short ip_id;
103
104 #ifdef MBUF_STRESS_TEST
105 int mbuf_frag_size = 0;
106 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
107 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
108 #endif
109
110 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *);
111 static struct ifnet *ip_multicast_if(struct in_addr *, int *);
112 static void ip_mloopback
113 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int);
114 static int ip_getmoptions
115 (struct sockopt *, struct ip_moptions *);
116 static int ip_pcbopts(int, struct mbuf **, struct mbuf *);
117 static int ip_setmoptions
118 (struct sockopt *, struct ip_moptions **);
119
120 int ip_optcopy(struct ip *, struct ip *);
121
122 extern int route_assert_owner_access;
123
124 extern struct protosw inetsw[];
125
126 static int
127 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst, int hlen)
128 {
129 struct in_ifaddr_container *iac;
130
131 /*
132 * We need to figure out if we have been forwarded to a local
133 * socket. If so, then we should somehow "loop back" to
134 * ip_input(), and get directed to the PCB as if we had received
135 * this packet. This is because it may be difficult to identify
136 * the packets you want to forward until they are being output
137 * and have selected an interface (e.g. locally initiated
138 * packets). If we used the loopback inteface, we would not be
139 * able to control what happens as the packet runs through
140 * ip_input() as it is done through a ISR.
141 */
142 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) {
143 /*
144 * If the addr to forward to is one of ours, we pretend
145 * to be the destination for this packet.
146 */
147 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr)
148 break;
149 }
150 if (iac != NULL) {
151 struct ip *ip;
152
153 if (m->m_pkthdr.rcvif == NULL)
154 m->m_pkthdr.rcvif = ifunit("lo0");
155 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
156 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID |
157 CSUM_PSEUDO_HDR;
158 m->m_pkthdr.csum_data = 0xffff;
159 }
160 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID;
161
162 /*
163 * Make sure that the IP header is in one mbuf,
164 * required by ip_input
165 */
166 if (m->m_len < hlen) {
167 m = m_pullup(m, hlen);
168 if (m == NULL) {
169 /* The packet was freed; we are done */
170 return 1;
171 }
172 }
173 ip = mtod(m, struct ip *);
174
175 ip->ip_len = htons(ip->ip_len);
176 ip->ip_off = htons(ip->ip_off);
177 ip_input(m);
178
179 return 1; /* The packet gets forwarded locally */
180 }
181 return 0;
182 }
183
184 /*
185 * IP output. The packet in mbuf chain m contains a skeletal IP
186 * header (with len, off, ttl, proto, tos, src, dst).
187 * The mbuf chain containing the packet will be freed.
188 * The mbuf opt, if present, will not be freed.
189 */
190 int
191 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro,
192 int flags, struct ip_moptions *imo, struct inpcb *inp)
193 {
194 struct ip *ip;
195 struct ifnet *ifp = NULL; /* keep compiler happy */
196 struct mbuf *m;
197 int hlen = sizeof(struct ip);
198 int len, error = 0;
199 struct sockaddr_in *dst = NULL; /* keep compiler happy */
200 struct in_ifaddr *ia = NULL;
201 int isbroadcast, sw_csum;
202 struct in_addr pkt_dst;
203 struct route iproute;
204 struct m_tag *mtag;
205 #ifdef IPSEC
206 struct secpolicy *sp = NULL;
207 struct socket *so = inp ? inp->inp_socket : NULL;
208 #endif
209 #ifdef FAST_IPSEC
210 struct secpolicy *sp = NULL;
211 struct tdb_ident *tdbi;
212 #endif /* FAST_IPSEC */
213 struct sockaddr_in *next_hop = NULL;
214 int src_was_INADDR_ANY = 0; /* as the name says... */
215
216 m = m0;
217 M_ASSERTPKTHDR(m);
218
219 if (ro == NULL) {
220 ro = &iproute;
221 bzero(ro, sizeof *ro);
222 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) {
223 if (flags & IP_DEBUGROUTE) {
224 if (route_assert_owner_access) {
225 panic("ip_output: "
226 "rt rt_cpuid %d accessed on cpu %d\n",
227 ro->ro_rt->rt_cpuid, mycpuid);
228 } else {
229 kprintf("ip_output: "
230 "rt rt_cpuid %d accessed on cpu %d\n",
231 ro->ro_rt->rt_cpuid, mycpuid);
232 print_backtrace();
233 }
234 }
235
236 /*
237 * XXX
238 * If the cached rtentry's owner CPU is not the current CPU,
239 * then don't touch the cached rtentry (remote free is too
240 * expensive in this context); just relocate the route.
241 */
242 ro = &iproute;
243 bzero(ro, sizeof *ro);
244 }
245
246 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
247 /* Next hop */
248 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
249 KKASSERT(mtag != NULL);
250 next_hop = m_tag_data(mtag);
251 }
252
253 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
254 struct dn_pkt *dn_pkt;
255
256 /* Extract info from dummynet tag */
257 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
258 KKASSERT(mtag != NULL);
259 dn_pkt = m_tag_data(mtag);
260
261 /*
262 * The packet was already tagged, so part of the
263 * processing was already done, and we need to go down.
264 * Get the calculated parameters from the tag.
265 */
266 ifp = dn_pkt->ifp;
267
268 KKASSERT(ro == &iproute);
269 *ro = dn_pkt->ro; /* structure copy */
270 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid);
271
272 dst = dn_pkt->dn_dst;
273 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) {
274 /* If 'dst' points into dummynet tag, adjust it */
275 dst = (struct sockaddr_in *)&(ro->ro_dst);
276 }
277
278 ip = mtod(m, struct ip *);
279 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ;
280 if (ro->ro_rt)
281 ia = ifatoia(ro->ro_rt->rt_ifa);
282 goto sendit;
283 }
284
285 if (opt) {
286 len = 0;
287 m = ip_insertoptions(m, opt, &len);
288 if (len != 0)
289 hlen = len;
290 }
291 ip = mtod(m, struct ip *);
292
293 /*
294 * Fill in IP header.
295 */
296 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) {
297 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2);
298 ip->ip_off &= IP_DF;
299 ip->ip_id = ip_newid();
300 ipstat.ips_localout++;
301 } else {
302 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
303 }
304
305 reroute:
306 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst;
307
308 #ifdef INVARIANTS
309 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
310 /*
311 * XXX
312 * Multicast is not MPSAFE yet. Caller must hold
313 * BGL when output a multicast IP packet.
314 */
315 ASSERT_MP_LOCK_HELD(curthread);
316 }
317 #endif
318
319 dst = (struct sockaddr_in *)&ro->ro_dst;
320 /*
321 * If there is a cached route,
322 * check that it is to the same destination
323 * and is still up. If not, free it and try again.
324 * The address family should also be checked in case of sharing the
325 * cache with IPv6.
326 */
327 if (ro->ro_rt &&
328 (!(ro->ro_rt->rt_flags & RTF_UP) ||
329 dst->sin_family != AF_INET ||
330 dst->sin_addr.s_addr != pkt_dst.s_addr)) {
331 rtfree(ro->ro_rt);
332 ro->ro_rt = NULL;
333 }
334 if (ro->ro_rt == NULL) {
335 bzero(dst, sizeof *dst);
336 dst->sin_family = AF_INET;
337 dst->sin_len = sizeof *dst;
338 dst->sin_addr = pkt_dst;
339 }
340 /*
341 * If routing to interface only,
342 * short circuit routing lookup.
343 */
344 if (flags & IP_ROUTETOIF) {
345 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL &&
346 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) {
347 ipstat.ips_noroute++;
348 error = ENETUNREACH;
349 goto bad;
350 }
351 ifp = ia->ia_ifp;
352 ip->ip_ttl = 1;
353 isbroadcast = in_broadcast(dst->sin_addr, ifp);
354 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) &&
355 imo != NULL && imo->imo_multicast_ifp != NULL) {
356 /*
357 * Bypass the normal routing lookup for multicast
358 * packets if the interface is specified.
359 */
360 ifp = imo->imo_multicast_ifp;
361 ia = IFP_TO_IA(ifp);
362 isbroadcast = 0; /* fool gcc */
363 } else {
364 /*
365 * If this is the case, we probably don't want to allocate
366 * a protocol-cloned route since we didn't get one from the
367 * ULP. This lets TCP do its thing, while not burdening
368 * forwarding or ICMP with the overhead of cloning a route.
369 * Of course, we still want to do any cloning requested by
370 * the link layer, as this is probably required in all cases
371 * for correct operation (as it is for ARP).
372 */
373 if (ro->ro_rt == NULL)
374 rtalloc_ign(ro, RTF_PRCLONING);
375 if (ro->ro_rt == NULL) {
376 ipstat.ips_noroute++;
377 error = EHOSTUNREACH;
378 goto bad;
379 }
380 ia = ifatoia(ro->ro_rt->rt_ifa);
381 ifp = ro->ro_rt->rt_ifp;
382 ro->ro_rt->rt_use++;
383 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
384 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
385 if (ro->ro_rt->rt_flags & RTF_HOST)
386 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
387 else
388 isbroadcast = in_broadcast(dst->sin_addr, ifp);
389 }
390 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
391 struct in_multi *inm;
392
393 m->m_flags |= M_MCAST;
394 /*
395 * IP destination address is multicast. Make sure "dst"
396 * still points to the address in "ro". (It may have been
397 * changed to point to a gateway address, above.)
398 */
399 dst = (struct sockaddr_in *)&ro->ro_dst;
400 /*
401 * See if the caller provided any multicast options
402 */
403 if (imo != NULL) {
404 ip->ip_ttl = imo->imo_multicast_ttl;
405 if (imo->imo_multicast_vif != -1) {
406 ip->ip_src.s_addr =
407 ip_mcast_src ?
408 ip_mcast_src(imo->imo_multicast_vif) :
409 INADDR_ANY;
410 }
411 } else {
412 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
413 }
414 /*
415 * Confirm that the outgoing interface supports multicast.
416 */
417 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
418 if (!(ifp->if_flags & IFF_MULTICAST)) {
419 ipstat.ips_noroute++;
420 error = ENETUNREACH;
421 goto bad;
422 }
423 }
424 /*
425 * If source address not specified yet, use address
426 * of outgoing interface.
427 */
428 if (ip->ip_src.s_addr == INADDR_ANY) {
429 /* Interface may have no addresses. */
430 if (ia != NULL)
431 ip->ip_src = IA_SIN(ia)->sin_addr;
432 }
433
434 IN_LOOKUP_MULTI(pkt_dst, ifp, inm);
435 if (inm != NULL &&
436 (imo == NULL || imo->imo_multicast_loop)) {
437 /*
438 * If we belong to the destination multicast group
439 * on the outgoing interface, and the caller did not
440 * forbid loopback, loop back a copy.
441 */
442 ip_mloopback(ifp, m, dst, hlen);
443 } else {
444 /*
445 * If we are acting as a multicast router, perform
446 * multicast forwarding as if the packet had just
447 * arrived on the interface to which we are about
448 * to send. The multicast forwarding function
449 * recursively calls this function, using the
450 * IP_FORWARDING flag to prevent infinite recursion.
451 *
452 * Multicasts that are looped back by ip_mloopback(),
453 * above, will be forwarded by the ip_input() routine,
454 * if necessary.
455 */
456 if (ip_mrouter && !(flags & IP_FORWARDING)) {
457 /*
458 * If rsvp daemon is not running, do not
459 * set ip_moptions. This ensures that the packet
460 * is multicast and not just sent down one link
461 * as prescribed by rsvpd.
462 */
463 if (!rsvp_on)
464 imo = NULL;
465 if (ip_mforward &&
466 ip_mforward(ip, ifp, m, imo) != 0) {
467 m_freem(m);
468 goto done;
469 }
470 }
471 }
472
473 /*
474 * Multicasts with a time-to-live of zero may be looped-
475 * back, above, but must not be transmitted on a network.
476 * Also, multicasts addressed to the loopback interface
477 * are not sent -- the above call to ip_mloopback() will
478 * loop back a copy if this host actually belongs to the
479 * destination group on the loopback interface.
480 */
481 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
482 m_freem(m);
483 goto done;
484 }
485
486 goto sendit;
487 } else {
488 m->m_flags &= ~M_MCAST;
489 }
490
491 /*
492 * If the source address is not specified yet, use the address
493 * of the outoing interface. In case, keep note we did that, so
494 * if the the firewall changes the next-hop causing the output
495 * interface to change, we can fix that.
496 */
497 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
498 /* Interface may have no addresses. */
499 if (ia != NULL) {
500 ip->ip_src = IA_SIN(ia)->sin_addr;
501 src_was_INADDR_ANY = 1;
502 }
503 }
504
505 #ifdef ALTQ
506 /*
507 * Disable packet drop hack.
508 * Packetdrop should be done by queueing.
509 */
510 #else /* !ALTQ */
511 /*
512 * Verify that we have any chance at all of being able to queue
513 * the packet or packet fragments
514 */
515 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >=
516 ifp->if_snd.ifq_maxlen) {
517 error = ENOBUFS;
518 ipstat.ips_odropped++;
519 goto bad;
520 }
521 #endif /* !ALTQ */
522
523 /*
524 * Look for broadcast address and
525 * verify user is allowed to send
526 * such a packet.
527 */
528 if (isbroadcast) {
529 if (!(ifp->if_flags & IFF_BROADCAST)) {
530 error = EADDRNOTAVAIL;
531 goto bad;
532 }
533 if (!(flags & IP_ALLOWBROADCAST)) {
534 error = EACCES;
535 goto bad;
536 }
537 /* don't allow broadcast messages to be fragmented */
538 if (ip->ip_len > ifp->if_mtu) {
539 error = EMSGSIZE;
540 goto bad;
541 }
542 m->m_flags |= M_BCAST;
543 } else {
544 m->m_flags &= ~M_BCAST;
545 }
546
547 sendit:
548 #ifdef IPSEC
549 /* get SP for this packet */
550 if (so == NULL)
551 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error);
552 else
553 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
554
555 if (sp == NULL) {
556 ipsecstat.out_inval++;
557 goto bad;
558 }
559
560 error = 0;
561
562 /* check policy */
563 switch (sp->policy) {
564 case IPSEC_POLICY_DISCARD:
565 /*
566 * This packet is just discarded.
567 */
568 ipsecstat.out_polvio++;
569 goto bad;
570
571 case IPSEC_POLICY_BYPASS:
572 case IPSEC_POLICY_NONE:
573 /* no need to do IPsec. */
574 goto skip_ipsec;
575
576 case IPSEC_POLICY_IPSEC:
577 if (sp->req == NULL) {
578 /* acquire a policy */
579 error = key_spdacquire(sp);
580 goto bad;
581 }
582 break;
583
584 case IPSEC_POLICY_ENTRUST:
585 default:
586 kprintf("ip_output: Invalid policy found. %d\n", sp->policy);
587 }
588 {
589 struct ipsec_output_state state;
590 bzero(&state, sizeof state);
591 state.m = m;
592 if (flags & IP_ROUTETOIF) {
593 state.ro = &iproute;
594 bzero(&iproute, sizeof iproute);
595 } else
596 state.ro = ro;
597 state.dst = (struct sockaddr *)dst;
598
599 ip->ip_sum = 0;
600
601 /*
602 * XXX
603 * delayed checksums are not currently compatible with IPsec
604 */
605 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
606 in_delayed_cksum(m);
607 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
608 }
609
610 ip->ip_len = htons(ip->ip_len);
611 ip->ip_off = htons(ip->ip_off);
612
613 error = ipsec4_output(&state, sp, flags);
614
615 m = state.m;
616 if (flags & IP_ROUTETOIF) {
617 /*
618 * if we have tunnel mode SA, we may need to ignore
619 * IP_ROUTETOIF.
620 */
621 if (state.ro != &iproute || state.ro->ro_rt != NULL) {
622 flags &= ~IP_ROUTETOIF;
623 ro = state.ro;
624 }
625 } else
626 ro = state.ro;
627 dst = (struct sockaddr_in *)state.dst;
628 if (error) {
629 /* mbuf is already reclaimed in ipsec4_output. */
630 m0 = NULL;
631 switch (error) {
632 case EHOSTUNREACH:
633 case ENETUNREACH:
634 case EMSGSIZE:
635 case ENOBUFS:
636 case ENOMEM:
637 break;
638 default:
639 kprintf("ip4_output (ipsec): error code %d\n", error);
640 /*fall through*/
641 case ENOENT:
642 /* don't show these error codes to the user */
643 error = 0;
644 break;
645 }
646 goto bad;
647 }
648 }
649
650 /* be sure to update variables that are affected by ipsec4_output() */
651 ip = mtod(m, struct ip *);
652 #ifdef _IP_VHL
653 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
654 #else
655 hlen = ip->ip_hl << 2;
656 #endif
657 if (ro->ro_rt == NULL) {
658 if (!(flags & IP_ROUTETOIF)) {
659 kprintf("ip_output: "
660 "can't update route after IPsec processing\n");
661 error = EHOSTUNREACH; /*XXX*/
662 goto bad;
663 }
664 } else {
665 ia = ifatoia(ro->ro_rt->rt_ifa);
666 ifp = ro->ro_rt->rt_ifp;
667 }
668
669 /* make it flipped, again. */
670 ip->ip_len = ntohs(ip->ip_len);
671 ip->ip_off = ntohs(ip->ip_off);
672 skip_ipsec:
673 #endif /*IPSEC*/
674 #ifdef FAST_IPSEC
675 /*
676 * Check the security policy (SP) for the packet and, if
677 * required, do IPsec-related processing. There are two
678 * cases here; the first time a packet is sent through
679 * it will be untagged and handled by ipsec4_checkpolicy.
680 * If the packet is resubmitted to ip_output (e.g. after
681 * AH, ESP, etc. processing), there will be a tag to bypass
682 * the lookup and related policy checking.
683 */
684 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
685 crit_enter();
686 if (mtag != NULL) {
687 tdbi = (struct tdb_ident *)m_tag_data(mtag);
688 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
689 if (sp == NULL)
690 error = -EINVAL; /* force silent drop */
691 m_tag_delete(m, mtag);
692 } else {
693 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags,
694 &error, inp);
695 }
696 /*
697 * There are four return cases:
698 * sp != NULL apply IPsec policy
699 * sp == NULL, error == 0 no IPsec handling needed
700 * sp == NULL, error == -EINVAL discard packet w/o error
701 * sp == NULL, error != 0 discard packet, report error
702 */
703 if (sp != NULL) {
704 /* Loop detection, check if ipsec processing already done */
705 KASSERT(sp->req != NULL, ("ip_output: no ipsec request"));
706 for (mtag = m_tag_first(m); mtag != NULL;
707 mtag = m_tag_next(m, mtag)) {
708 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
709 continue;
710 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
711 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
712 continue;
713 /*
714 * Check if policy has an SA associated with it.
715 * This can happen when an SP has yet to acquire
716 * an SA; e.g. on first reference. If it occurs,
717 * then we let ipsec4_process_packet do its thing.
718 */
719 if (sp->req->sav == NULL)
720 break;
721 tdbi = (struct tdb_ident *)m_tag_data(mtag);
722 if (tdbi->spi == sp->req->sav->spi &&
723 tdbi->proto == sp->req->sav->sah->saidx.proto &&
724 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst,
725 sizeof(union sockaddr_union)) == 0) {
726 /*
727 * No IPsec processing is needed, free
728 * reference to SP.
729 *
730 * NB: null pointer to avoid free at
731 * done: below.
732 */
733 KEY_FREESP(&sp), sp = NULL;
734 crit_exit();
735 goto spd_done;
736 }
737 }
738
739 /*
740 * Do delayed checksums now because we send before
741 * this is done in the normal processing path.
742 */
743 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
744 in_delayed_cksum(m);
745 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
746 }
747
748 ip->ip_len = htons(ip->ip_len);
749 ip->ip_off = htons(ip->ip_off);
750
751 /* NB: callee frees mbuf */
752 error = ipsec4_process_packet(m, sp->req, flags, 0);
753 /*
754 * Preserve KAME behaviour: ENOENT can be returned
755 * when an SA acquire is in progress. Don't propagate
756 * this to user-level; it confuses applications.
757 *
758 * XXX this will go away when the SADB is redone.
759 */
760 if (error == ENOENT)
761 error = 0;
762 crit_exit();
763 goto done;
764 } else {
765 crit_exit();
766
767 if (error != 0) {
768 /*
769 * Hack: -EINVAL is used to signal that a packet
770 * should be silently discarded. This is typically
771 * because we asked key management for an SA and
772 * it was delayed (e.g. kicked up to IKE).
773 */
774 if (error == -EINVAL)
775 error = 0;
776 goto bad;
777 } else {
778 /* No IPsec processing for this packet. */
779 }
780 #ifdef notyet
781 /*
782 * If deferred crypto processing is needed, check that
783 * the interface supports it.
784 */
785 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL);
786 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) {
787 /* notify IPsec to do its own crypto */
788 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag));
789 error = EHOSTUNREACH;
790 goto bad;
791 }
792 #endif
793 }
794 spd_done:
795 #endif /* FAST_IPSEC */
796
797 /* We are already being fwd'd from a firewall. */
798 if (next_hop != NULL)
799 goto pass;
800
801 /* No pfil hooks */
802 if (!pfil_has_hooks(&inet_pfil_hook)) {
803 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
804 /*
805 * Strip dummynet tags from stranded packets
806 */
807 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
808 KKASSERT(mtag != NULL);
809 m_tag_delete(m, mtag);
810 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED;
811 }
812 goto pass;
813 }
814
815 /*
816 * IpHack's section.
817 * - Xlate: translate packet's addr/port (NAT).
818 * - Firewall: deny/allow/etc.
819 * - Wrap: fake packet's addr/port <unimpl.>
820 * - Encapsulate: put it in another IP and send out. <unimp.>
821 */
822
823 /*
824 * Run through list of hooks for output packets.
825 */
826 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT);
827 if (error != 0 || m == NULL)
828 goto done;
829 ip = mtod(m, struct ip *);
830
831 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
832 /*
833 * Check dst to make sure it is directly reachable on the
834 * interface we previously thought it was.
835 * If it isn't (which may be likely in some situations) we have
836 * to re-route it (ie, find a route for the next-hop and the
837 * associated interface) and set them here. This is nested
838 * forwarding which in most cases is undesirable, except where
839 * such control is nigh impossible. So we do it here.
840 * And I'm babbling.
841 */
842 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
843 KKASSERT(mtag != NULL);
844 next_hop = m_tag_data(mtag);
845
846 /*
847 * Try local forwarding first
848 */
849 if (ip_localforward(m, next_hop, hlen))
850 goto done;
851
852 /*
853 * Relocate the route based on next_hop.
854 * If the current route is inp's cache, keep it untouched.
855 */
856 if (ro == &iproute && ro->ro_rt != NULL) {
857 RTFREE(ro->ro_rt);
858 ro->ro_rt = NULL;
859 }
860 ro = &iproute;
861 bzero(ro, sizeof *ro);
862
863 /*
864 * Forwarding to broadcast address is not allowed.
865 * XXX Should we follow IP_ROUTETOIF?
866 */
867 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF);
868
869 /* We are doing forwarding now */
870 flags |= IP_FORWARDING;
871
872 goto reroute;
873 }
874
875 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
876 struct dn_pkt *dn_pkt;
877
878 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
879 KKASSERT(mtag != NULL);
880 dn_pkt = m_tag_data(mtag);
881
882 /*
883 * Under certain cases it is not possible to recalculate
884 * 'ro' and 'dst', let alone 'flags', so just save them in
885 * dummynet tag and avoid the possible wrong reculcalation
886 * when we come back to ip_output() again.
887 *
888 * All other parameters have been already used and so they
889 * are not needed anymore.
890 * XXX if the ifp is deleted while a pkt is in dummynet,
891 * we are in trouble! (TODO use ifnet_detach_event)
892 *
893 * We need to copy *ro because for ICMP pkts (and maybe
894 * others) the caller passed a pointer into the stack;
895 * dst might also be a pointer into *ro so it needs to
896 * be updated.
897 */
898 dn_pkt->ro = *ro;
899 if (ro->ro_rt)
900 ro->ro_rt->rt_refcnt++;
901 if (dst == (struct sockaddr_in *)&ro->ro_dst) {
902 /* 'dst' points into 'ro' */
903 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst);
904 }
905 dn_pkt->dn_dst = dst;
906 dn_pkt->flags = flags;
907
908 ip_dn_queue(m);
909 goto done;
910 }
911 pass:
912 /* 127/8 must not appear on wire - RFC1122. */
913 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
914 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
915 if (!(ifp->if_flags & IFF_LOOPBACK)) {
916 ipstat.ips_badaddr++;
917 error = EADDRNOTAVAIL;
918 goto bad;
919 }
920 }
921
922 m->m_pkthdr.csum_flags |= CSUM_IP;
923 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
924 if (sw_csum & CSUM_DELAY_DATA) {
925 in_delayed_cksum(m);
926 sw_csum &= ~CSUM_DELAY_DATA;
927 }
928 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
929
930 /*
931 * If small enough for interface, or the interface will take
932 * care of the fragmentation for us, can just send directly.
933 */
934 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) &&
935 !(ip->ip_off & IP_DF))) {
936 ip->ip_len = htons(ip->ip_len);
937 ip->ip_off = htons(ip->ip_off);
938 ip->ip_sum = 0;
939 if (sw_csum & CSUM_DELAY_IP) {
940 if (ip->ip_vhl == IP_VHL_BORING)
941 ip->ip_sum = in_cksum_hdr(ip);
942 else
943 ip->ip_sum = in_cksum(m, hlen);
944 }
945
946 /* Record statistics for this interface address. */
947 if (!(flags & IP_FORWARDING) && ia) {
948 ia->ia_ifa.if_opackets++;
949 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
950 }
951
952 #ifdef IPSEC
953 /* clean ipsec history once it goes out of the node */
954 ipsec_delaux(m);
955 #endif
956
957 #ifdef MBUF_STRESS_TEST
958 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) {
959 struct mbuf *m1, *m2;
960 int length, tmp;
961
962 tmp = length = m->m_pkthdr.len;
963
964 while ((length -= mbuf_frag_size) >= 1) {
965 m1 = m_split(m, length, MB_DONTWAIT);
966 if (m1 == NULL)
967 break;
968 m2 = m;
969 while (m2->m_next != NULL)
970 m2 = m2->m_next;
971 m2->m_next = m1;
972 }
973 m->m_pkthdr.len = tmp;
974 }
975 #endif
976
977 #ifdef MPLS
978 if (!mpls_output_process(m, ro->ro_rt))
979 goto done;
980 #endif
981 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
982 ro->ro_rt);
983 goto done;
984 }
985
986 if (ip->ip_off & IP_DF) {
987 error = EMSGSIZE;
988 /*
989 * This case can happen if the user changed the MTU
990 * of an interface after enabling IP on it. Because
991 * most netifs don't keep track of routes pointing to
992 * them, there is no way for one to update all its
993 * routes when the MTU is changed.
994 */
995 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) &&
996 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) &&
997 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) {
998 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
999 }
1000 ipstat.ips_cantfrag++;
1001 goto bad;
1002 }
1003
1004 /*
1005 * Too large for interface; fragment if possible. If successful,
1006 * on return, m will point to a list of packets to be sent.
1007 */
1008 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum);
1009 if (error)
1010 goto bad;
1011 for (; m; m = m0) {
1012 m0 = m->m_nextpkt;
1013 m->m_nextpkt = NULL;
1014 #ifdef IPSEC
1015 /* clean ipsec history once it goes out of the node */
1016 ipsec_delaux(m);
1017 #endif
1018 if (error == 0) {
1019 /* Record statistics for this interface address. */
1020 if (ia != NULL) {
1021 ia->ia_ifa.if_opackets++;
1022 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
1023 }
1024 #ifdef MPLS
1025 if (!mpls_output_process(m, ro->ro_rt))
1026 continue;
1027 #endif
1028 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
1029 ro->ro_rt);
1030 } else {
1031 m_freem(m);
1032 }
1033 }
1034
1035 if (error == 0)
1036 ipstat.ips_fragmented++;
1037
1038 done:
1039 if (ro == &iproute && ro->ro_rt != NULL) {
1040 RTFREE(ro->ro_rt);
1041 ro->ro_rt = NULL;
1042 }
1043 #ifdef IPSEC
1044 if (sp != NULL) {
1045 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1046 kprintf("DP ip_output call free SP:%p\n", sp));
1047 key_freesp(sp);
1048 }
1049 #endif
1050 #ifdef FAST_IPSEC
1051 if (sp != NULL)
1052 KEY_FREESP(&sp);
1053 #endif
1054 return (error);
1055 bad:
1056 m_freem(m);
1057 goto done;
1058 }
1059
1060 /*
1061 * Create a chain of fragments which fit the given mtu. m_frag points to the
1062 * mbuf to be fragmented; on return it points to the chain with the fragments.
1063 * Return 0 if no error. If error, m_frag may contain a partially built
1064 * chain of fragments that should be freed by the caller.
1065 *
1066 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
1067 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
1068 */
1069 int
1070 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
1071 u_long if_hwassist_flags, int sw_csum)
1072 {
1073 int error = 0;
1074 int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
1075 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
1076 int off;
1077 struct mbuf *m0 = *m_frag; /* the original packet */
1078 int firstlen;
1079 struct mbuf **mnext;
1080 int nfrags;
1081
1082 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */
1083 ipstat.ips_cantfrag++;
1084 return EMSGSIZE;
1085 }
1086
1087 /*
1088 * Must be able to put at least 8 bytes per fragment.
1089 */
1090 if (len < 8)
1091 return EMSGSIZE;
1092
1093 /*
1094 * If the interface will not calculate checksums on
1095 * fragmented packets, then do it here.
1096 */
1097 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) &&
1098 !(if_hwassist_flags & CSUM_IP_FRAGS)) {
1099 in_delayed_cksum(m0);
1100 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1101 }
1102
1103 if (len > PAGE_SIZE) {
1104 /*
1105 * Fragment large datagrams such that each segment
1106 * contains a multiple of PAGE_SIZE amount of data,
1107 * plus headers. This enables a receiver to perform
1108 * page-flipping zero-copy optimizations.
1109 *
1110 * XXX When does this help given that sender and receiver
1111 * could have different page sizes, and also mtu could
1112 * be less than the receiver's page size ?
1113 */
1114 int newlen;
1115 struct mbuf *m;
1116
1117 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next)
1118 off += m->m_len;
1119
1120 /*
1121 * firstlen (off - hlen) must be aligned on an
1122 * 8-byte boundary
1123 */
1124 if (off < hlen)
1125 goto smart_frag_failure;
1126 off = ((off - hlen) & ~7) + hlen;
1127 newlen = (~PAGE_MASK) & mtu;
1128 if ((newlen + sizeof(struct ip)) > mtu) {
1129 /* we failed, go back the default */
1130 smart_frag_failure:
1131 newlen = len;
1132 off = hlen + len;
1133 }
1134 len = newlen;
1135
1136 } else {
1137 off = hlen + len;
1138 }
1139
1140 firstlen = off - hlen;
1141 mnext = &m0->m_nextpkt; /* pointer to next packet */
1142
1143 /*
1144 * Loop through length of segment after first fragment,
1145 * make new header and copy data of each part and link onto chain.
1146 * Here, m0 is the original packet, m is the fragment being created.
1147 * The fragments are linked off the m_nextpkt of the original
1148 * packet, which after processing serves as the first fragment.
1149 */
1150 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) {
1151 struct ip *mhip; /* ip header on the fragment */
1152 struct mbuf *m;
1153 int mhlen = sizeof(struct ip);
1154
1155 MGETHDR(m, MB_DONTWAIT, MT_HEADER);
1156 if (m == NULL) {
1157 error = ENOBUFS;
1158 ipstat.ips_odropped++;
1159 goto done;
1160 }
1161 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
1162 /*
1163 * In the first mbuf, leave room for the link header, then
1164 * copy the original IP header including options. The payload
1165 * goes into an additional mbuf chain returned by m_copy().
1166 */
1167 m->m_data += max_linkhdr;
1168 mhip = mtod(m, struct ip *);
1169 *mhip = *ip;
1170 if (hlen > sizeof(struct ip)) {
1171 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip);
1172 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2);
1173 }
1174 m->m_len = mhlen;
1175 /* XXX do we need to add ip->ip_off below ? */
1176 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
1177 if (off + len >= ip->ip_len) { /* last fragment */
1178 len = ip->ip_len - off;
1179 m->m_flags |= M_LASTFRAG;
1180 } else
1181 mhip->ip_off |= IP_MF;
1182 mhip->ip_len = htons((u_short)(len + mhlen));
1183 m->m_next = m_copy(m0, off, len);
1184 if (m->m_next == NULL) { /* copy failed */
1185 m_free(m);
1186 error = ENOBUFS; /* ??? */
1187 ipstat.ips_odropped++;
1188 goto done;
1189 }
1190 m->m_pkthdr.len = mhlen + len;
1191 m->m_pkthdr.rcvif = NULL;
1192 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
1193 mhip->ip_off = htons(mhip->ip_off);
1194 mhip->ip_sum = 0;
1195 if (sw_csum & CSUM_DELAY_IP)
1196 mhip->ip_sum = in_cksum(m, mhlen);
1197 *mnext = m;
1198 mnext = &m->m_nextpkt;
1199 }
1200 ipstat.ips_ofragments += nfrags;
1201
1202 /* set first marker for fragment chain */
1203 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1204 m0->m_pkthdr.csum_data = nfrags;
1205
1206 /*
1207 * Update first fragment by trimming what's been copied out
1208 * and updating header.
1209 */
1210 m_adj(m0, hlen + firstlen - ip->ip_len);
1211 m0->m_pkthdr.len = hlen + firstlen;
1212 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1213 ip->ip_off |= IP_MF;
1214 ip->ip_off = htons(ip->ip_off);
1215 ip->ip_sum = 0;
1216 if (sw_csum & CSUM_DELAY_IP)
1217 ip->ip_sum = in_cksum(m0, hlen);
1218
1219 done:
1220 *m_frag = m0;
1221 return error;
1222 }
1223
1224 void
1225 in_delayed_cksum(struct mbuf *m)
1226 {
1227 struct ip *ip;
1228 u_short csum, offset;
1229
1230 ip = mtod(m, struct ip *);
1231 offset = IP_VHL_HL(ip->ip_vhl) << 2 ;
1232 csum = in_cksum_skip(m, ip->ip_len, offset);
1233 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
1234 csum = 0xffff;
1235 offset += m->m_pkthdr.csum_data; /* checksum offset */
1236
1237 if (offset + sizeof(u_short) > m->m_len) {
1238 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n",
1239 m->m_len, offset, ip->ip_p);
1240 /*
1241 * XXX
1242 * this shouldn't happen, but if it does, the
1243 * correct behavior may be to insert the checksum
1244 * in the existing chain instead of rearranging it.
1245 */
1246 m = m_pullup(m, offset + sizeof(u_short));
1247 }
1248 *(u_short *)(m->m_data + offset) = csum;
1249 }
1250
1251 /*
1252 * Insert IP options into preformed packet.
1253 * Adjust IP destination as required for IP source routing,
1254 * as indicated by a non-zero in_addr at the start of the options.
1255 *
1256 * XXX This routine assumes that the packet has no options in place.
1257 */
1258 static struct mbuf *
1259 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen)
1260 {
1261 struct ipoption *p = mtod(opt, struct ipoption *);
1262 struct mbuf *n;
1263 struct ip *ip = mtod(m, struct ip *);
1264 unsigned optlen;
1265
1266 optlen = opt->m_len - sizeof p->ipopt_dst;
1267 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) {
1268 *phlen = 0;
1269 return (m); /* XXX should fail */
1270 }
1271 if (p->ipopt_dst.s_addr)
1272 ip->ip_dst = p->ipopt_dst;
1273 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
1274 MGETHDR(n, MB_DONTWAIT, MT_HEADER);
1275 if (n == NULL) {
1276 *phlen = 0;
1277 return (m);
1278 }
1279 n->m_pkthdr.rcvif = NULL;
1280 n->m_pkthdr.len = m->m_pkthdr.len + optlen;
1281 m->m_len -= sizeof(struct ip);
1282 m->m_data += sizeof(struct ip);
1283 n->m_next = m;
1284 m = n;
1285 m->m_len = optlen + sizeof(struct ip);
1286 m->m_data += max_linkhdr;
1287 memcpy(mtod(m, void *), ip, sizeof(struct ip));
1288 } else {
1289 m->m_data -= optlen;
1290 m->m_len += optlen;
1291 m->m_pkthdr.len += optlen;
1292 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip));
1293 }
1294 ip = mtod(m, struct ip *);
1295 bcopy(p->ipopt_list, ip + 1, optlen);
1296 *phlen = sizeof(struct ip) + optlen;
1297 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2);
1298 ip->ip_len += optlen;
1299 return (m);
1300 }
1301
1302 /*
1303 * Copy options from ip to jp,
1304 * omitting those not copied during fragmentation.
1305 */
1306 int
1307 ip_optcopy(struct ip *ip, struct ip *jp)
1308 {
1309 u_char *cp, *dp;
1310 int opt, optlen, cnt;
1311
1312 cp = (u_char *)(ip + 1);
1313 dp = (u_char *)(jp + 1);
1314 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
1315 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1316 opt = cp[0];
1317 if (opt == IPOPT_EOL)
1318 break;
1319 if (opt == IPOPT_NOP) {
1320 /* Preserve for IP mcast tunnel's LSRR alignment. */
1321 *dp++ = IPOPT_NOP;
1322 optlen = 1;
1323 continue;
1324 }
1325
1326 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp,
1327 ("ip_optcopy: malformed ipv4 option"));
1328 optlen = cp[IPOPT_OLEN];
1329 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt,
1330 ("ip_optcopy: malformed ipv4 option"));
1331
1332 /* bogus lengths should have been caught by ip_dooptions */
1333 if (optlen > cnt)
1334 optlen = cnt;
1335 if (IPOPT_COPIED(opt)) {
1336 bcopy(cp, dp, optlen);
1337 dp += optlen;
1338 }
1339 }
1340 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
1341 *dp++ = IPOPT_EOL;
1342 return (optlen);
1343 }
1344
1345 /*
1346 * IP socket option processing.
1347 */
1348 int
1349 ip_ctloutput(struct socket *so, struct sockopt *sopt)
1350 {
1351 struct inpcb *inp = so->so_pcb;
1352 int error, optval;
1353
1354 error = optval = 0;
1355 if (sopt->sopt_level != IPPROTO_IP) {
1356 return (EINVAL);
1357 }
1358
1359 switch (sopt->sopt_dir) {
1360 case SOPT_SET:
1361 switch (sopt->sopt_name) {
1362 case IP_OPTIONS:
1363 #ifdef notyet
1364 case IP_RETOPTS:
1365 #endif
1366 {
1367 struct mbuf *m;
1368 if (sopt->sopt_valsize > MLEN) {
1369 error = EMSGSIZE;
1370 break;
1371 }
1372 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER);
1373 if (m == NULL) {
1374 error = ENOBUFS;
1375 break;
1376 }
1377 m->m_len = sopt->sopt_valsize;
1378 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len,
1379 m->m_len);
1380 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options,
1381 m));
1382 }
1383
1384 case IP_TOS:
1385 case IP_TTL:
1386 case IP_MINTTL:
1387 case IP_RECVOPTS:
1388 case IP_RECVRETOPTS:
1389 case IP_RECVDSTADDR:
1390 case IP_RECVIF:
1391 case IP_RECVTTL:
1392 case IP_FAITH:
1393 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1394 sizeof optval);
1395 if (error)
1396 break;
1397 switch (sopt->sopt_name) {
1398 case IP_TOS:
1399 inp->inp_ip_tos = optval;
1400 break;
1401
1402 case IP_TTL:
1403 inp->inp_ip_ttl = optval;
1404 break;
1405 case IP_MINTTL:
1406 if (optval >= 0 && optval <= MAXTTL)
1407 inp->inp_ip_minttl = optval;
1408 else
1409 error = EINVAL;
1410 break;
1411 #define OPTSET(bit) \
1412 if (optval) \
1413 inp->inp_flags |= bit; \
1414 else \
1415 inp->inp_flags &= ~bit;
1416
1417 case IP_RECVOPTS:
1418 OPTSET(INP_RECVOPTS);
1419 break;
1420
1421 case IP_RECVRETOPTS:
1422 OPTSET(INP_RECVRETOPTS);
1423 break;
1424
1425 case IP_RECVDSTADDR:
1426 OPTSET(INP_RECVDSTADDR);
1427 break;
1428
1429 case IP_RECVIF:
1430 OPTSET(INP_RECVIF);
1431 break;
1432
1433 case IP_RECVTTL:
1434 OPTSET(INP_RECVTTL);
1435 break;
1436
1437 case IP_FAITH:
1438 OPTSET(INP_FAITH);
1439 break;
1440 }
1441 break;
1442 #undef OPTSET
1443
1444 case IP_MULTICAST_IF:
1445 case IP_MULTICAST_VIF:
1446 case IP_MULTICAST_TTL:
1447 case IP_MULTICAST_LOOP:
1448 case IP_ADD_MEMBERSHIP:
1449 case IP_DROP_MEMBERSHIP:
1450 error = ip_setmoptions(sopt, &inp->inp_moptions);
1451 break;
1452
1453 case IP_PORTRANGE:
1454 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1455 sizeof optval);
1456 if (error)
1457 break;
1458
1459 switch (optval) {
1460 case IP_PORTRANGE_DEFAULT:
1461 inp->inp_flags &= ~(INP_LOWPORT);
1462 inp->inp_flags &= ~(INP_HIGHPORT);
1463 break;
1464
1465 case IP_PORTRANGE_HIGH:
1466 inp->inp_flags &= ~(INP_LOWPORT);
1467 inp->inp_flags |= INP_HIGHPORT;
1468 break;
1469
1470 case IP_PORTRANGE_LOW:
1471 inp->inp_flags &= ~(INP_HIGHPORT);
1472 inp->inp_flags |= INP_LOWPORT;
1473 break;
1474
1475 default:
1476 error = EINVAL;
1477 break;
1478 }
1479 break;
1480
1481 #if defined(IPSEC) || defined(FAST_IPSEC)
1482 case IP_IPSEC_POLICY:
1483 {
1484 caddr_t req;
1485 size_t len = 0;
1486 int priv;
1487 struct mbuf *m;
1488 int optname;
1489
1490 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1491 break;
1492 soopt_to_mbuf(sopt, m);
1493 priv = (sopt->sopt_td != NULL &&
1494 priv_check(sopt->sopt_td, PRIV_ROOT) != 0) ? 0 : 1;
1495 req = mtod(m, caddr_t);
1496 len = m->m_len;
1497 optname = sopt->sopt_name;
1498 error = ipsec4_set_policy(inp, optname, req, len, priv);
1499 m_freem(m);
1500 break;
1501 }
1502 #endif /*IPSEC*/
1503
1504 default:
1505 error = ENOPROTOOPT;
1506 break;
1507 }
1508 break;
1509
1510 case SOPT_GET:
1511 switch (sopt->sopt_name) {
1512 case IP_OPTIONS:
1513 case IP_RETOPTS:
1514 if (inp->inp_options)
1515 soopt_from_kbuf(sopt, mtod(inp->inp_options,
1516 char *),
1517 inp->inp_options->m_len);
1518 else
1519 sopt->sopt_valsize = 0;
1520 break;
1521
1522 case IP_TOS:
1523 case IP_TTL:
1524 case IP_MINTTL:
1525 case IP_RECVOPTS:
1526 case IP_RECVRETOPTS:
1527 case IP_RECVDSTADDR:
1528 case IP_RECVTTL:
1529 case IP_RECVIF:
1530 case IP_PORTRANGE:
1531 case IP_FAITH:
1532 switch (sopt->sopt_name) {
1533
1534 case IP_TOS:
1535 optval = inp->inp_ip_tos;
1536 break;
1537
1538 case IP_TTL:
1539 optval = inp->inp_ip_ttl;
1540 break;
1541 case IP_MINTTL:
1542 optval = inp->inp_ip_minttl;
1543 break;
1544
1545 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1546
1547 case IP_RECVOPTS:
1548 optval = OPTBIT(INP_RECVOPTS);
1549 break;
1550
1551 case IP_RECVRETOPTS:
1552 optval = OPTBIT(INP_RECVRETOPTS);
1553 break;
1554
1555 case IP_RECVDSTADDR:
1556 optval = OPTBIT(INP_RECVDSTADDR);
1557 break;
1558
1559 case IP_RECVTTL:
1560 optval = OPTBIT(INP_RECVTTL);
1561 break;
1562
1563 case IP_RECVIF:
1564 optval = OPTBIT(INP_RECVIF);
1565 break;
1566
1567 case IP_PORTRANGE:
1568 if (inp->inp_flags & INP_HIGHPORT)
1569 optval = IP_PORTRANGE_HIGH;
1570 else if (inp->inp_flags & INP_LOWPORT)
1571 optval = IP_PORTRANGE_LOW;
1572 else
1573 optval = 0;
1574 break;
1575
1576 case IP_FAITH:
1577 optval = OPTBIT(INP_FAITH);
1578 break;
1579 }
1580 soopt_from_kbuf(sopt, &optval, sizeof optval);
1581 break;
1582
1583 case IP_MULTICAST_IF:
1584 case IP_MULTICAST_VIF:
1585 case IP_MULTICAST_TTL:
1586 case IP_MULTICAST_LOOP:
1587 case IP_ADD_MEMBERSHIP:
1588 case IP_DROP_MEMBERSHIP:
1589 error = ip_getmoptions(sopt, inp->inp_moptions);
1590 break;
1591
1592 #if defined(IPSEC) || defined(FAST_IPSEC)
1593 case IP_IPSEC_POLICY:
1594 {
1595 struct mbuf *m = NULL;
1596 caddr_t req = NULL;
1597 size_t len = 0;
1598
1599 if (m != NULL) {
1600 req = mtod(m, caddr_t);
1601 len = m->m_len;
1602 }
1603 error = ipsec4_get_policy(so->so_pcb, req, len, &m);
1604 if (error == 0)
1605 error = soopt_from_mbuf(sopt, m); /* XXX */
1606 if (error == 0)
1607 m_freem(m);
1608 break;
1609 }
1610 #endif /*IPSEC*/
1611
1612 default:
1613 error = ENOPROTOOPT;
1614 break;
1615 }
1616 break;
1617 }
1618 return (error);
1619 }
1620
1621 /*
1622 * Set up IP options in pcb for insertion in output packets.
1623 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1624 * with destination address if source routed.
1625 */
1626 static int
1627 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m)
1628 {
1629 int cnt, optlen;
1630 u_char *cp;
1631 u_char opt;
1632
1633 /* turn off any old options */
1634 if (*pcbopt)
1635 m_free(*pcbopt);
1636 *pcbopt = 0;
1637 if (m == NULL || m->m_len == 0) {
1638 /*
1639 * Only turning off any previous options.
1640 */
1641 if (m != NULL)
1642 m_free(m);
1643 return (0);
1644 }
1645
1646 if (m->m_len % sizeof(int32_t))
1647 goto bad;
1648 /*
1649 * IP first-hop destination address will be stored before
1650 * actual options; move other options back
1651 * and clear it when none present.
1652 */
1653 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
1654 goto bad;
1655 cnt = m->m_len;
1656 m->m_len += sizeof(struct in_addr);
1657 cp = mtod(m, u_char *) + sizeof(struct in_addr);
1658 ovbcopy(mtod(m, caddr_t), cp, cnt);
1659 bzero(mtod(m, caddr_t), sizeof(struct in_addr));
1660
1661 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1662 opt = cp[IPOPT_OPTVAL];
1663 if (opt == IPOPT_EOL)
1664 break;
1665 if (opt == IPOPT_NOP)
1666 optlen = 1;
1667 else {
1668 if (cnt < IPOPT_OLEN + sizeof *cp)
1669 goto bad;
1670 optlen = cp[IPOPT_OLEN];
1671 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt)
1672 goto bad;
1673 }
1674 switch (opt) {
1675
1676 default:
1677 break;
1678
1679 case IPOPT_LSRR:
1680 case IPOPT_SSRR:
1681 /*
1682 * user process specifies route as:
1683 * ->A->B->C->D
1684 * D must be our final destination (but we can't
1685 * check that since we may not have connected yet).
1686 * A is first hop destination, which doesn't appear in
1687 * actual IP option, but is stored before the options.
1688 */
1689 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
1690 goto bad;
1691 m->m_len -= sizeof(struct in_addr);
1692 cnt -= sizeof(struct in_addr);
1693 optlen -= sizeof(struct in_addr);
1694 cp[IPOPT_OLEN] = optlen;
1695 /*
1696 * Move first hop before start of options.
1697 */
1698 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
1699 sizeof(struct in_addr));
1700 /*
1701 * Then copy rest of options back
1702 * to close up the deleted entry.
1703 */
1704 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr),
1705 &cp[IPOPT_OFFSET+1],
1706 cnt - (IPOPT_MINOFF - 1));
1707 break;
1708 }
1709 }
1710 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
1711 goto bad;
1712 *pcbopt = m;
1713 return (0);
1714
1715 bad:
1716 m_free(m);
1717 return (EINVAL);
1718 }
1719
1720 /*
1721 * XXX
1722 * The whole multicast option thing needs to be re-thought.
1723 * Several of these options are equally applicable to non-multicast
1724 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1725 * standard option (IP_TTL).
1726 */
1727
1728 /*
1729 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1730 */
1731 static struct ifnet *
1732 ip_multicast_if(struct in_addr *a, int *ifindexp)
1733 {
1734 int ifindex;
1735 struct ifnet *ifp;
1736
1737 if (ifindexp)
1738 *ifindexp = 0;
1739 if (ntohl(a->s_addr) >> 24 == 0) {
1740 ifindex = ntohl(a->s_addr) & 0xffffff;
1741 if (ifindex < 0 || if_index < ifindex)
1742 return NULL;
1743 ifp = ifindex2ifnet[ifindex];
1744 if (ifindexp)
1745 *ifindexp = ifindex;
1746 } else {
1747 ifp = INADDR_TO_IFP(a);
1748 }
1749 return ifp;
1750 }
1751
1752 /*
1753 * Set the IP multicast options in response to user setsockopt().
1754 */
1755 static int
1756 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop)
1757 {
1758 int error = 0;
1759 int i;
1760 struct in_addr addr;
1761 struct ip_mreq mreq;
1762 struct ifnet *ifp;
1763 struct ip_moptions *imo = *imop;
1764 int ifindex;
1765
1766 if (imo == NULL) {
1767 /*
1768 * No multicast option buffer attached to the pcb;
1769 * allocate one and initialize to default values.
1770 */
1771 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK);
1772
1773 *imop = imo;
1774 imo->imo_multicast_ifp = NULL;
1775 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1776 imo->imo_multicast_vif = -1;
1777 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1778 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
1779 imo->imo_num_memberships = 0;
1780 }
1781 switch (sopt->sopt_name) {
1782 /* store an index number for the vif you wanna use in the send */
1783 case IP_MULTICAST_VIF:
1784 if (legal_vif_num == 0) {
1785 error = EOPNOTSUPP;
1786 break;
1787 }
1788 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i);
1789 if (error)
1790 break;
1791 if (!legal_vif_num(i) && (i != -1)) {
1792 error = EINVAL;
1793 break;
1794 }
1795 imo->imo_multicast_vif = i;
1796 break;
1797
1798 case IP_MULTICAST_IF:
1799 /*
1800 * Select the interface for outgoing multicast packets.
1801 */
1802 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr);
1803 if (error)
1804 break;
1805
1806 /*
1807 * INADDR_ANY is used to remove a previous selection.
1808 * When no interface is selected, a default one is
1809 * chosen every time a multicast packet is sent.
1810 */
1811 if (addr.s_addr == INADDR_ANY) {
1812 imo->imo_multicast_ifp = NULL;
1813 break;
1814 }
1815 /*
1816 * The selected interface is identified by its local
1817 * IP address. Find the interface and confirm that
1818 * it supports multicasting.
1819 */
1820 crit_enter();
1821 ifp = ip_multicast_if(&addr, &ifindex);
1822 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1823 crit_exit();
1824 error = EADDRNOTAVAIL;
1825 break;
1826 }
1827 imo->imo_multicast_ifp = ifp;
1828 if (ifindex)
1829 imo->imo_multicast_addr = addr;
1830 else
1831 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1832 crit_exit();
1833 break;
1834
1835 case IP_MULTICAST_TTL:
1836 /*
1837 * Set the IP time-to-live for outgoing multicast packets.
1838 * The original multicast API required a char argument,
1839 * which is inconsistent with the rest of the socket API.
1840 * We allow either a char or an int.
1841 */
1842 if (sopt->sopt_valsize == 1) {
1843 u_char ttl;
1844 error = soopt_to_kbuf(sopt, &ttl, 1, 1);
1845 if (error)
1846 break;
1847 imo->imo_multicast_ttl = ttl;
1848 } else {
1849 u_int ttl;
1850 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl);
1851 if (error)
1852 break;
1853 if (ttl > 255)
1854 error = EINVAL;
1855 else
1856 imo->imo_multicast_ttl = ttl;
1857 }
1858 break;
1859
1860 case IP_MULTICAST_LOOP:
1861 /*
1862 * Set the loopback flag for outgoing multicast packets.
1863 * Must be zero or one. The original multicast API required a
1864 * char argument, which is inconsistent with the rest
1865 * of the socket API. We allow either a char or an int.
1866 */
1867 if (sopt->sopt_valsize == 1) {
1868 u_char loop;
1869
1870 error = soopt_to_kbuf(sopt, &loop, 1, 1);
1871 if (error)
1872 break;
1873 imo->imo_multicast_loop = !!loop;
1874 } else {
1875 u_int loop;
1876
1877 error = soopt_to_kbuf(sopt, &loop, sizeof loop,
1878 sizeof loop);
1879 if (error)
1880 break;
1881 imo->imo_multicast_loop = !!loop;
1882 }
1883 break;
1884
1885 case IP_ADD_MEMBERSHIP:
1886 /*
1887 * Add a multicast group membership.
1888 * Group must be a valid IP multicast address.
1889 */
1890 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1891 if (error)
1892 break;
1893
1894 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1895 error = EINVAL;
1896 break;
1897 }
1898 crit_enter();
1899 /*
1900 * If no interface address was provided, use the interface of
1901 * the route to the given multicast address.
1902 */
1903 if (mreq.imr_interface.s_addr == INADDR_ANY) {
1904 struct sockaddr_in dst;
1905 struct rtentry *rt;
1906
1907 bzero(&dst, sizeof(struct sockaddr_in));
1908 dst.sin_len = sizeof(struct sockaddr_in);
1909 dst.sin_family = AF_INET;
1910 dst.sin_addr = mreq.imr_multiaddr;
1911 rt = rtlookup((struct sockaddr *)&dst);
1912 if (rt == NULL) {
1913 error = EADDRNOTAVAIL;
1914 crit_exit();
1915 break;
1916 }
1917 --rt->rt_refcnt;
1918 ifp = rt->rt_ifp;
1919 } else {
1920 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1921 }
1922
1923 /*
1924 * See if we found an interface, and confirm that it
1925 * supports multicast.
1926 */
1927 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1928 error = EADDRNOTAVAIL;
1929 crit_exit();
1930 break;
1931 }
1932 /*
1933 * See if the membership already exists or if all the
1934 * membership slots are full.
1935 */
1936 for (i = 0; i < imo->imo_num_memberships; ++i) {
1937 if (imo->imo_membership[i]->inm_ifp == ifp &&
1938 imo->imo_membership[i]->inm_addr.s_addr
1939 == mreq.imr_multiaddr.s_addr)
1940 break;
1941 }
1942 if (i < imo->imo_num_memberships) {
1943 error = EADDRINUSE;
1944 crit_exit();
1945 break;
1946 }
1947 if (i == IP_MAX_MEMBERSHIPS) {
1948 error = ETOOMANYREFS;
1949 crit_exit();
1950 break;
1951 }
1952 /*
1953 * Everything looks good; add a new record to the multicast
1954 * address list for the given interface.
1955 */
1956 if ((imo->imo_membership[i] =
1957 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) {
1958 error = ENOBUFS;
1959 crit_exit();
1960 break;
1961 }
1962 ++imo->imo_num_memberships;
1963 crit_exit();
1964 break;
1965
1966 case IP_DROP_MEMBERSHIP:
1967 /*
1968 * Drop a multicast group membership.
1969 * Group must be a valid IP multicast address.
1970 */
1971 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1972 if (error)
1973 break;
1974
1975 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1976 error = EINVAL;
1977 break;
1978 }
1979
1980 crit_enter();
1981 /*
1982 * If an interface address was specified, get a pointer
1983 * to its ifnet structure.
1984 */
1985 if (mreq.imr_interface.s_addr == INADDR_ANY)
1986 ifp = NULL;
1987 else {
1988 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1989 if (ifp == NULL) {
1990 error = EADDRNOTAVAIL;
1991 crit_exit();
1992 break;
1993 }
1994 }
1995 /*
1996 * Find the membership in the membership array.
1997 */
1998 for (i = 0; i < imo->imo_num_memberships; ++i) {
1999 if ((ifp == NULL ||
2000 imo->imo_membership[i]->inm_ifp == ifp) &&
2001 imo->imo_membership[i]->inm_addr.s_addr ==
2002 mreq.imr_multiaddr.s_addr)
2003 break;
2004 }
2005 if (i == imo->imo_num_memberships) {
2006 error = EADDRNOTAVAIL;
2007 crit_exit();
2008 break;
2009 }
2010 /*
2011 * Give up the multicast address record to which the
2012 * membership points.
2013 */
2014 in_delmulti(imo->imo_membership[i]);
2015 /*
2016 * Remove the gap in the membership array.
2017 */
2018 for (++i; i < imo->imo_num_memberships; ++i)
2019 imo->imo_membership[i-1] = imo->imo_membership[i];
2020 --imo->imo_num_memberships;
2021 crit_exit();
2022 break;
2023
2024 default:
2025 error = EOPNOTSUPP;
2026 break;
2027 }
2028
2029 /*
2030 * If all options have default values, no need to keep the mbuf.
2031 */
2032 if (imo->imo_multicast_ifp == NULL &&
2033 imo->imo_multicast_vif == -1 &&
2034 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
2035 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
2036 imo->imo_num_memberships == 0) {
2037 kfree(*imop, M_IPMOPTS);
2038 *imop = NULL;
2039 }
2040
2041 return (error);
2042 }
2043
2044 /*
2045 * Return the IP multicast options in response to user getsockopt().
2046 */
2047 static int
2048 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo)
2049 {
2050 struct in_addr addr;
2051 struct in_ifaddr *ia;
2052 int error, optval;
2053 u_char coptval;
2054
2055 error = 0;
2056 switch (sopt->sopt_name) {
2057 case IP_MULTICAST_VIF:
2058 if (imo != NULL)
2059 optval = imo->imo_multicast_vif;
2060 else
2061 optval = -1;
2062 soopt_from_kbuf(sopt, &optval, sizeof optval);
2063 break;
2064
2065 case IP_MULTICAST_IF:
2066 if (imo == NULL || imo->imo_multicast_ifp == NULL)
2067 addr.s_addr = INADDR_ANY;
2068 else if (imo->imo_multicast_addr.s_addr) {
2069 /* return the value user has set */
2070 addr = imo->imo_multicast_addr;
2071 } else {
2072 ia = IFP_TO_IA(imo->imo_multicast_ifp);
2073 addr.s_addr = (ia == NULL) ? INADDR_ANY
2074 : IA_SIN(ia)->sin_addr.s_addr;
2075 }
2076 soopt_from_kbuf(sopt, &addr, sizeof addr);
2077 break;
2078
2079 case IP_MULTICAST_TTL:
2080 if (imo == NULL)
2081 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
2082 else
2083 optval = coptval = imo->imo_multicast_ttl;
2084 if (sopt->sopt_valsize == 1)
2085 soopt_from_kbuf(sopt, &coptval, 1);
2086 else
2087 soopt_from_kbuf(sopt, &optval, sizeof optval);
2088 break;
2089
2090 case IP_MULTICAST_LOOP:
2091 if (imo == NULL)
2092 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
2093 else
2094 optval = coptval = imo->imo_multicast_loop;
2095 if (sopt->sopt_valsize == 1)
2096 soopt_from_kbuf(sopt, &coptval, 1);
2097 else
2098 soopt_from_kbuf(sopt, &optval, sizeof optval);
2099 break;
2100
2101 default:
2102 error = ENOPROTOOPT;
2103 break;
2104 }
2105 return (error);
2106 }
2107
2108 /*
2109 * Discard the IP multicast options.
2110 */
2111 void
2112 ip_freemoptions(struct ip_moptions *imo)
2113 {
2114 int i;
2115
2116 if (imo != NULL) {
2117 for (i = 0; i < imo->imo_num_memberships; ++i)
2118 in_delmulti(imo->imo_membership[i]);
2119 kfree(imo, M_IPMOPTS);
2120 }
2121 }
2122
2123 /*
2124 * Routine called from ip_output() to loop back a copy of an IP multicast
2125 * packet to the input queue of a specified interface. Note that this
2126 * calls the output routine of the loopback "driver", but with an interface
2127 * pointer that might NOT be a loopback interface -- evil, but easier than
2128 * replicating that code here.
2129 */
2130 static void
2131 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst,
2132 int hlen)
2133 {
2134 struct ip *ip;
2135 struct mbuf *copym;
2136
2137 copym = m_copypacket(m, MB_DONTWAIT);
2138 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
2139 copym = m_pullup(copym, hlen);
2140 if (copym != NULL) {
2141 /*
2142 * if the checksum hasn't been computed, mark it as valid
2143 */
2144 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2145 in_delayed_cksum(copym);
2146 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
2147 copym->m_pkthdr.csum_flags |=
2148 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2149 copym->m_pkthdr.csum_data = 0xffff;
2150 }
2151 /*
2152 * We don't bother to fragment if the IP length is greater
2153 * than the interface's MTU. Can this possibly matter?
2154 */
2155 ip = mtod(copym, struct ip *);
2156 ip->ip_len = htons(ip->ip_len);
2157 ip->ip_off = htons(ip->ip_off);
2158 ip->ip_sum = 0;
2159 if (ip->ip_vhl == IP_VHL_BORING) {
2160 ip->ip_sum = in_cksum_hdr(ip);
2161 } else {
2162 ip->ip_sum = in_cksum(copym, hlen);
2163 }
2164 /*
2165 * NB:
2166 * It's not clear whether there are any lingering
2167 * reentrancy problems in other areas which might
2168 * be exposed by using ip_input directly (in
2169 * particular, everything which modifies the packet
2170 * in-place). Yet another option is using the
2171 * protosw directly to deliver the looped back
2172 * packet. For the moment, we'll err on the side
2173 * of safety by using if_simloop().
2174 */
2175 #if 1 /* XXX */
2176 if (dst->sin_family != AF_INET) {
2177 kprintf("ip_mloopback: bad address family %d\n",
2178 dst->sin_family);
2179 dst->sin_family = AF_INET;
2180 }
2181 #endif
2182 if_simloop(ifp, copym, dst->sin_family, 0);
2183 }
2184 }
DragonFly BSD