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If there are no pfil hooks, just remove the dummynet tag (for packets that
[dragonfly.git] / sys / netinet / ip_output.c
blob802fc305440e3fea80eb7d6d9d3b47b11535d49f
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 1.64 2008/09/18 11:19:42 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/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 extern int route_assert_owner_access;
119 extern void db_print_backtrace(void);
120
121 extern struct protosw inetsw[];
122
123 static int
124 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst)
125 {
126 struct in_ifaddr_container *iac;
127
128 /*
129 * We need to figure out if we have been forwarded to a local
130 * socket. If so, then we should somehow "loop back" to
131 * ip_input(), and get directed to the PCB as if we had received
132 * this packet. This is because it may be difficult to identify
133 * the packets you want to forward until they are being output
134 * and have selected an interface (e.g. locally initiated
135 * packets). If we used the loopback inteface, we would not be
136 * able to control what happens as the packet runs through
137 * ip_input() as it is done through a ISR.
138 */
139 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) {
140 /*
141 * If the addr to forward to is one of ours, we pretend
142 * to be the destination for this packet.
143 */
144 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr)
145 break;
146 }
147 if (iac != NULL) {
148 struct ip *ip = mtod(m, struct ip *);
149
150 if (m->m_pkthdr.rcvif == NULL)
151 m->m_pkthdr.rcvif = ifunit("lo0");
152 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
153 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID |
154 CSUM_PSEUDO_HDR;
155 m->m_pkthdr.csum_data = 0xffff;
156 }
157 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID;
158
159 ip->ip_len = htons(ip->ip_len);
160 ip->ip_off = htons(ip->ip_off);
161 ip_input(m);
162
163 return 1; /* Packet gets forwarded locally */
164 }
165 return 0;
166 }
167
168 /*
169 * IP output. The packet in mbuf chain m contains a skeletal IP
170 * header (with len, off, ttl, proto, tos, src, dst).
171 * The mbuf chain containing the packet will be freed.
172 * The mbuf opt, if present, will not be freed.
173 */
174 int
175 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro,
176 int flags, struct ip_moptions *imo, struct inpcb *inp)
177 {
178 struct ip *ip;
179 struct ifnet *ifp = NULL; /* keep compiler happy */
180 struct mbuf *m;
181 int hlen = sizeof(struct ip);
182 int len, error = 0;
183 struct sockaddr_in *dst = NULL; /* keep compiler happy */
184 struct in_ifaddr *ia = NULL;
185 int isbroadcast, sw_csum;
186 struct in_addr pkt_dst;
187 struct route iproute;
188 struct m_tag *mtag;
189 #ifdef IPSEC
190 struct secpolicy *sp = NULL;
191 struct socket *so = inp ? inp->inp_socket : NULL;
192 #endif
193 #ifdef FAST_IPSEC
194 struct secpolicy *sp = NULL;
195 struct tdb_ident *tdbi;
196 #endif /* FAST_IPSEC */
197 struct sockaddr_in *next_hop = NULL;
198 int src_was_INADDR_ANY = 0; /* as the name says... */
199
200 m = m0;
201 M_ASSERTPKTHDR(m);
202
203 if (ro == NULL) {
204 ro = &iproute;
205 bzero(ro, sizeof *ro);
206 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) {
207 if (flags & IP_DEBUGROUTE) {
208 if (route_assert_owner_access) {
209 panic("ip_output: "
210 "rt rt_cpuid %d accessed on cpu %d\n",
211 ro->ro_rt->rt_cpuid, mycpuid);
212 } else {
213 kprintf("ip_output: "
214 "rt rt_cpuid %d accessed on cpu %d\n",
215 ro->ro_rt->rt_cpuid, mycpuid);
216 db_print_backtrace();
217 }
218 }
219
220 /*
221 * XXX
222 * If the cached rtentry's owner CPU is not the current CPU,
223 * then don't touch the cached rtentry (remote free is too
224 * expensive in this context); just relocate the route.
225 */
226 ro = &iproute;
227 bzero(ro, sizeof *ro);
228 }
229
230 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
231 /* Next hop */
232 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
233 KKASSERT(mtag != NULL);
234 next_hop = m_tag_data(mtag);
235 }
236
237 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
238 struct dn_pkt *dn_pkt;
239
240 /* Extract info from dummynet tag */
241 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
242 KKASSERT(mtag != NULL);
243 dn_pkt = m_tag_data(mtag);
244
245 /*
246 * The packet was already tagged, so part of the
247 * processing was already done, and we need to go down.
248 * Get the calculated parameters from the tag.
249 */
250 ifp = dn_pkt->ifp;
251
252 KKASSERT(ro == &iproute);
253 *ro = dn_pkt->ro; /* structure copy */
254 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid);
255
256 dst = dn_pkt->dn_dst;
257 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) {
258 /* If 'dst' points into dummynet tag, adjust it */
259 dst = (struct sockaddr_in *)&(ro->ro_dst);
260 }
261
262 ip = mtod(m, struct ip *);
263 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ;
264 if (ro->ro_rt)
265 ia = ifatoia(ro->ro_rt->rt_ifa);
266 goto sendit;
267 }
268
269 if (opt) {
270 len = 0;
271 m = ip_insertoptions(m, opt, &len);
272 if (len != 0)
273 hlen = len;
274 }
275 ip = mtod(m, struct ip *);
276
277 /*
278 * Fill in IP header.
279 */
280 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) {
281 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2);
282 ip->ip_off &= IP_DF;
283 ip->ip_id = ip_newid();
284 ipstat.ips_localout++;
285 } else {
286 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
287 }
288
289 reroute:
290 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst;
291
292 dst = (struct sockaddr_in *)&ro->ro_dst;
293 /*
294 * If there is a cached route,
295 * check that it is to the same destination
296 * and is still up. If not, free it and try again.
297 * The address family should also be checked in case of sharing the
298 * cache with IPv6.
299 */
300 if (ro->ro_rt &&
301 (!(ro->ro_rt->rt_flags & RTF_UP) ||
302 dst->sin_family != AF_INET ||
303 dst->sin_addr.s_addr != pkt_dst.s_addr)) {
304 rtfree(ro->ro_rt);
305 ro->ro_rt = (struct rtentry *)NULL;
306 }
307 if (ro->ro_rt == NULL) {
308 bzero(dst, sizeof *dst);
309 dst->sin_family = AF_INET;
310 dst->sin_len = sizeof *dst;
311 dst->sin_addr = pkt_dst;
312 }
313 /*
314 * If routing to interface only,
315 * short circuit routing lookup.
316 */
317 if (flags & IP_ROUTETOIF) {
318 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL &&
319 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) {
320 ipstat.ips_noroute++;
321 error = ENETUNREACH;
322 goto bad;
323 }
324 ifp = ia->ia_ifp;
325 ip->ip_ttl = 1;
326 isbroadcast = in_broadcast(dst->sin_addr, ifp);
327 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) &&
328 imo != NULL && imo->imo_multicast_ifp != NULL) {
329 /*
330 * Bypass the normal routing lookup for multicast
331 * packets if the interface is specified.
332 */
333 ifp = imo->imo_multicast_ifp;
334 ia = IFP_TO_IA(ifp);
335 isbroadcast = 0; /* fool gcc */
336 } else {
337 /*
338 * If this is the case, we probably don't want to allocate
339 * a protocol-cloned route since we didn't get one from the
340 * ULP. This lets TCP do its thing, while not burdening
341 * forwarding or ICMP with the overhead of cloning a route.
342 * Of course, we still want to do any cloning requested by
343 * the link layer, as this is probably required in all cases
344 * for correct operation (as it is for ARP).
345 */
346 if (ro->ro_rt == NULL)
347 rtalloc_ign(ro, RTF_PRCLONING);
348 if (ro->ro_rt == NULL) {
349 ipstat.ips_noroute++;
350 error = EHOSTUNREACH;
351 goto bad;
352 }
353 ia = ifatoia(ro->ro_rt->rt_ifa);
354 ifp = ro->ro_rt->rt_ifp;
355 ro->ro_rt->rt_use++;
356 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
357 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
358 if (ro->ro_rt->rt_flags & RTF_HOST)
359 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
360 else
361 isbroadcast = in_broadcast(dst->sin_addr, ifp);
362 }
363 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
364 struct in_multi *inm;
365
366 m->m_flags |= M_MCAST;
367 /*
368 * IP destination address is multicast. Make sure "dst"
369 * still points to the address in "ro". (It may have been
370 * changed to point to a gateway address, above.)
371 */
372 dst = (struct sockaddr_in *)&ro->ro_dst;
373 /*
374 * See if the caller provided any multicast options
375 */
376 if (imo != NULL) {
377 ip->ip_ttl = imo->imo_multicast_ttl;
378 if (imo->imo_multicast_vif != -1)
379 ip->ip_src.s_addr =
380 ip_mcast_src ?
381 ip_mcast_src(imo->imo_multicast_vif) :
382 INADDR_ANY;
383 } else
384 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
385 /*
386 * Confirm that the outgoing interface supports multicast.
387 */
388 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
389 if (!(ifp->if_flags & IFF_MULTICAST)) {
390 ipstat.ips_noroute++;
391 error = ENETUNREACH;
392 goto bad;
393 }
394 }
395 /*
396 * If source address not specified yet, use address
397 * of outgoing interface.
398 */
399 if (ip->ip_src.s_addr == INADDR_ANY) {
400 /* Interface may have no addresses. */
401 if (ia != NULL)
402 ip->ip_src = IA_SIN(ia)->sin_addr;
403 }
404
405 IN_LOOKUP_MULTI(pkt_dst, ifp, inm);
406 if (inm != NULL &&
407 (imo == NULL || imo->imo_multicast_loop)) {
408 /*
409 * If we belong to the destination multicast group
410 * on the outgoing interface, and the caller did not
411 * forbid loopback, loop back a copy.
412 */
413 ip_mloopback(ifp, m, dst, hlen);
414 }
415 else {
416 /*
417 * If we are acting as a multicast router, perform
418 * multicast forwarding as if the packet had just
419 * arrived on the interface to which we are about
420 * to send. The multicast forwarding function
421 * recursively calls this function, using the
422 * IP_FORWARDING flag to prevent infinite recursion.
423 *
424 * Multicasts that are looped back by ip_mloopback(),
425 * above, will be forwarded by the ip_input() routine,
426 * if necessary.
427 */
428 if (ip_mrouter && !(flags & IP_FORWARDING)) {
429 /*
430 * If rsvp daemon is not running, do not
431 * set ip_moptions. This ensures that the packet
432 * is multicast and not just sent down one link
433 * as prescribed by rsvpd.
434 */
435 if (!rsvp_on)
436 imo = NULL;
437 if (ip_mforward &&
438 ip_mforward(ip, ifp, m, imo) != 0) {
439 m_freem(m);
440 goto done;
441 }
442 }
443 }
444
445 /*
446 * Multicasts with a time-to-live of zero may be looped-
447 * back, above, but must not be transmitted on a network.
448 * Also, multicasts addressed to the loopback interface
449 * are not sent -- the above call to ip_mloopback() will
450 * loop back a copy if this host actually belongs to the
451 * destination group on the loopback interface.
452 */
453 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
454 m_freem(m);
455 goto done;
456 }
457
458 goto sendit;
459 } else {
460 m->m_flags &= ~M_MCAST;
461 }
462
463 /*
464 * If the source address is not specified yet, use the address
465 * of the outoing interface. In case, keep note we did that, so
466 * if the the firewall changes the next-hop causing the output
467 * interface to change, we can fix that.
468 */
469 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
470 /* Interface may have no addresses. */
471 if (ia != NULL) {
472 ip->ip_src = IA_SIN(ia)->sin_addr;
473 src_was_INADDR_ANY = 1;
474 }
475 }
476
477 #ifdef ALTQ
478 /*
479 * Disable packet drop hack.
480 * Packetdrop should be done by queueing.
481 */
482 #else /* !ALTQ */
483 /*
484 * Verify that we have any chance at all of being able to queue
485 * the packet or packet fragments
486 */
487 if ((ifp->if_snd.ifq_len + ip->ip_len / ifp->if_mtu + 1) >=
488 ifp->if_snd.ifq_maxlen) {
489 error = ENOBUFS;
490 ipstat.ips_odropped++;
491 goto bad;
492 }
493 #endif /* !ALTQ */
494
495 /*
496 * Look for broadcast address and
497 * verify user is allowed to send
498 * such a packet.
499 */
500 if (isbroadcast) {
501 if (!(ifp->if_flags & IFF_BROADCAST)) {
502 error = EADDRNOTAVAIL;
503 goto bad;
504 }
505 if (!(flags & IP_ALLOWBROADCAST)) {
506 error = EACCES;
507 goto bad;
508 }
509 /* don't allow broadcast messages to be fragmented */
510 if (ip->ip_len > ifp->if_mtu) {
511 error = EMSGSIZE;
512 goto bad;
513 }
514 m->m_flags |= M_BCAST;
515 } else {
516 m->m_flags &= ~M_BCAST;
517 }
518
519 sendit:
520 #ifdef IPSEC
521 /* get SP for this packet */
522 if (so == NULL)
523 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error);
524 else
525 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
526
527 if (sp == NULL) {
528 ipsecstat.out_inval++;
529 goto bad;
530 }
531
532 error = 0;
533
534 /* check policy */
535 switch (sp->policy) {
536 case IPSEC_POLICY_DISCARD:
537 /*
538 * This packet is just discarded.
539 */
540 ipsecstat.out_polvio++;
541 goto bad;
542
543 case IPSEC_POLICY_BYPASS:
544 case IPSEC_POLICY_NONE:
545 /* no need to do IPsec. */
546 goto skip_ipsec;
547
548 case IPSEC_POLICY_IPSEC:
549 if (sp->req == NULL) {
550 /* acquire a policy */
551 error = key_spdacquire(sp);
552 goto bad;
553 }
554 break;
555
556 case IPSEC_POLICY_ENTRUST:
557 default:
558 kprintf("ip_output: Invalid policy found. %d\n", sp->policy);
559 }
560 {
561 struct ipsec_output_state state;
562 bzero(&state, sizeof state);
563 state.m = m;
564 if (flags & IP_ROUTETOIF) {
565 state.ro = &iproute;
566 bzero(&iproute, sizeof iproute);
567 } else
568 state.ro = ro;
569 state.dst = (struct sockaddr *)dst;
570
571 ip->ip_sum = 0;
572
573 /*
574 * XXX
575 * delayed checksums are not currently compatible with IPsec
576 */
577 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
578 in_delayed_cksum(m);
579 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
580 }
581
582 ip->ip_len = htons(ip->ip_len);
583 ip->ip_off = htons(ip->ip_off);
584
585 error = ipsec4_output(&state, sp, flags);
586
587 m = state.m;
588 if (flags & IP_ROUTETOIF) {
589 /*
590 * if we have tunnel mode SA, we may need to ignore
591 * IP_ROUTETOIF.
592 */
593 if (state.ro != &iproute || state.ro->ro_rt != NULL) {
594 flags &= ~IP_ROUTETOIF;
595 ro = state.ro;
596 }
597 } else
598 ro = state.ro;
599 dst = (struct sockaddr_in *)state.dst;
600 if (error) {
601 /* mbuf is already reclaimed in ipsec4_output. */
602 m0 = NULL;
603 switch (error) {
604 case EHOSTUNREACH:
605 case ENETUNREACH:
606 case EMSGSIZE:
607 case ENOBUFS:
608 case ENOMEM:
609 break;
610 default:
611 kprintf("ip4_output (ipsec): error code %d\n", error);
612 /*fall through*/
613 case ENOENT:
614 /* don't show these error codes to the user */
615 error = 0;
616 break;
617 }
618 goto bad;
619 }
620 }
621
622 /* be sure to update variables that are affected by ipsec4_output() */
623 ip = mtod(m, struct ip *);
624 #ifdef _IP_VHL
625 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
626 #else
627 hlen = ip->ip_hl << 2;
628 #endif
629 if (ro->ro_rt == NULL) {
630 if (!(flags & IP_ROUTETOIF)) {
631 kprintf("ip_output: "
632 "can't update route after IPsec processing\n");
633 error = EHOSTUNREACH; /*XXX*/
634 goto bad;
635 }
636 } else {
637 ia = ifatoia(ro->ro_rt->rt_ifa);
638 ifp = ro->ro_rt->rt_ifp;
639 }
640
641 /* make it flipped, again. */
642 ip->ip_len = ntohs(ip->ip_len);
643 ip->ip_off = ntohs(ip->ip_off);
644 skip_ipsec:
645 #endif /*IPSEC*/
646 #ifdef FAST_IPSEC
647 /*
648 * Check the security policy (SP) for the packet and, if
649 * required, do IPsec-related processing. There are two
650 * cases here; the first time a packet is sent through
651 * it will be untagged and handled by ipsec4_checkpolicy.
652 * If the packet is resubmitted to ip_output (e.g. after
653 * AH, ESP, etc. processing), there will be a tag to bypass
654 * the lookup and related policy checking.
655 */
656 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
657 crit_enter();
658 if (mtag != NULL) {
659 tdbi = (struct tdb_ident *)m_tag_data(mtag);
660 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
661 if (sp == NULL)
662 error = -EINVAL; /* force silent drop */
663 m_tag_delete(m, mtag);
664 } else {
665 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags,
666 &error, inp);
667 }
668 /*
669 * There are four return cases:
670 * sp != NULL apply IPsec policy
671 * sp == NULL, error == 0 no IPsec handling needed
672 * sp == NULL, error == -EINVAL discard packet w/o error
673 * sp == NULL, error != 0 discard packet, report error
674 */
675 if (sp != NULL) {
676 /* Loop detection, check if ipsec processing already done */
677 KASSERT(sp->req != NULL, ("ip_output: no ipsec request"));
678 for (mtag = m_tag_first(m); mtag != NULL;
679 mtag = m_tag_next(m, mtag)) {
680 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
681 continue;
682 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
683 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
684 continue;
685 /*
686 * Check if policy has an SA associated with it.
687 * This can happen when an SP has yet to acquire
688 * an SA; e.g. on first reference. If it occurs,
689 * then we let ipsec4_process_packet do its thing.
690 */
691 if (sp->req->sav == NULL)
692 break;
693 tdbi = (struct tdb_ident *)m_tag_data(mtag);
694 if (tdbi->spi == sp->req->sav->spi &&
695 tdbi->proto == sp->req->sav->sah->saidx.proto &&
696 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst,
697 sizeof(union sockaddr_union)) == 0) {
698 /*
699 * No IPsec processing is needed, free
700 * reference to SP.
701 *
702 * NB: null pointer to avoid free at
703 * done: below.
704 */
705 KEY_FREESP(&sp), sp = NULL;
706 crit_exit();
707 goto spd_done;
708 }
709 }
710
711 /*
712 * Do delayed checksums now because we send before
713 * this is done in the normal processing path.
714 */
715 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
716 in_delayed_cksum(m);
717 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
718 }
719
720 ip->ip_len = htons(ip->ip_len);
721 ip->ip_off = htons(ip->ip_off);
722
723 /* NB: callee frees mbuf */
724 error = ipsec4_process_packet(m, sp->req, flags, 0);
725 /*
726 * Preserve KAME behaviour: ENOENT can be returned
727 * when an SA acquire is in progress. Don't propagate
728 * this to user-level; it confuses applications.
729 *
730 * XXX this will go away when the SADB is redone.
731 */
732 if (error == ENOENT)
733 error = 0;
734 crit_exit();
735 goto done;
736 } else {
737 crit_exit();
738
739 if (error != 0) {
740 /*
741 * Hack: -EINVAL is used to signal that a packet
742 * should be silently discarded. This is typically
743 * because we asked key management for an SA and
744 * it was delayed (e.g. kicked up to IKE).
745 */
746 if (error == -EINVAL)
747 error = 0;
748 goto bad;
749 } else {
750 /* No IPsec processing for this packet. */
751 }
752 #ifdef notyet
753 /*
754 * If deferred crypto processing is needed, check that
755 * the interface supports it.
756 */
757 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL);
758 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) {
759 /* notify IPsec to do its own crypto */
760 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag));
761 error = EHOSTUNREACH;
762 goto bad;
763 }
764 #endif
765 }
766 spd_done:
767 #endif /* FAST_IPSEC */
768
769 /* We are already being fwd'd from a firewall. */
770 if (next_hop != NULL)
771 goto pass;
772
773 /* No pfil hooks */
774 if (!pfil_has_hooks(&inet_pfil_hook)) {
775 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
776 /*
777 * Strip dummynet tags from stranded packets
778 */
779 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
780 KKASSERT(mtag != NULL);
781 m_tag_delete(m, mtag);
782 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED;
783 }
784 goto pass;
785 }
786
787 /*
788 * IpHack's section.
789 * - Xlate: translate packet's addr/port (NAT).
790 * - Firewall: deny/allow/etc.
791 * - Wrap: fake packet's addr/port <unimpl.>
792 * - Encapsulate: put it in another IP and send out. <unimp.>
793 */
794
795 /*
796 * Run through list of hooks for output packets.
797 */
798 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT);
799 if (error != 0 || m == NULL)
800 goto done;
801 ip = mtod(m, struct ip *);
802
803 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
804 /*
805 * Check dst to make sure it is directly reachable on the
806 * interface we previously thought it was.
807 * If it isn't (which may be likely in some situations) we have
808 * to re-route it (ie, find a route for the next-hop and the
809 * associated interface) and set them here. This is nested
810 * forwarding which in most cases is undesirable, except where
811 * such control is nigh impossible. So we do it here.
812 * And I'm babbling.
813 */
814 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
815 KKASSERT(mtag != NULL);
816 next_hop = m_tag_data(mtag);
817
818 /*
819 * Try local forwarding first
820 */
821 if (ip_localforward(m, next_hop))
822 goto done;
823
824 /*
825 * Relocate the route based on next_hop.
826 * If the current route is inp's cache, keep it untouched.
827 */
828 if (ro == &iproute && ro->ro_rt != NULL) {
829 RTFREE(ro->ro_rt);
830 ro->ro_rt = NULL;
831 }
832 ro = &iproute;
833 bzero(ro, sizeof *ro);
834
835 /*
836 * Forwarding to broadcast address is not allowed.
837 * XXX Should we follow IP_ROUTETOIF?
838 */
839 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF);
840
841 /* We are doing forwarding now */
842 flags |= IP_FORWARDING;
843
844 goto reroute;
845 }
846
847 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
848 struct dn_pkt *dn_pkt;
849
850 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
851 KKASSERT(mtag != NULL);
852 dn_pkt = m_tag_data(mtag);
853
854 /*
855 * Under certain cases it is not possible to recalculate
856 * 'ro' and 'dst', let alone 'flags', so just save them in
857 * dummynet tag and avoid the possible wrong reculcalation
858 * when we come back to ip_output() again.
859 *
860 * All other parameters have been already used and so they
861 * are not needed anymore.
862 * XXX if the ifp is deleted while a pkt is in dummynet,
863 * we are in trouble! (TODO use ifnet_detach_event)
864 *
865 * We need to copy *ro because for ICMP pkts (and maybe
866 * others) the caller passed a pointer into the stack;
867 * dst might also be a pointer into *ro so it needs to
868 * be updated.
869 */
870 dn_pkt->ro = *ro;
871 if (ro->ro_rt)
872 ro->ro_rt->rt_refcnt++;
873 if (dst == (struct sockaddr_in *)&ro->ro_dst) {
874 /* 'dst' points into 'ro' */
875 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst);
876 }
877 dn_pkt->dn_dst = dst;
878 dn_pkt->flags = flags;
879
880 ip_dn_queue(m);
881 goto done;
882 }
883 pass:
884 /* 127/8 must not appear on wire - RFC1122. */
885 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
886 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
887 if (!(ifp->if_flags & IFF_LOOPBACK)) {
888 ipstat.ips_badaddr++;
889 error = EADDRNOTAVAIL;
890 goto bad;
891 }
892 }
893
894 m->m_pkthdr.csum_flags |= CSUM_IP;
895 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
896 if (sw_csum & CSUM_DELAY_DATA) {
897 in_delayed_cksum(m);
898 sw_csum &= ~CSUM_DELAY_DATA;
899 }
900 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
901
902 /*
903 * If small enough for interface, or the interface will take
904 * care of the fragmentation for us, can just send directly.
905 */
906 if (ip->ip_len <= ifp->if_mtu || ((ifp->if_hwassist & CSUM_FRAGMENT) &&
907 !(ip->ip_off & IP_DF))) {
908 ip->ip_len = htons(ip->ip_len);
909 ip->ip_off = htons(ip->ip_off);
910 ip->ip_sum = 0;
911 if (sw_csum & CSUM_DELAY_IP) {
912 if (ip->ip_vhl == IP_VHL_BORING) {
913 ip->ip_sum = in_cksum_hdr(ip);
914 } else {
915 ip->ip_sum = in_cksum(m, hlen);
916 }
917 }
918
919 /* Record statistics for this interface address. */
920 if (!(flags & IP_FORWARDING) && ia) {
921 ia->ia_ifa.if_opackets++;
922 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
923 }
924
925 #ifdef IPSEC
926 /* clean ipsec history once it goes out of the node */
927 ipsec_delaux(m);
928 #endif
929
930 #ifdef MBUF_STRESS_TEST
931 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) {
932 struct mbuf *m1, *m2;
933 int length, tmp;
934
935 tmp = length = m->m_pkthdr.len;
936
937 while ((length -= mbuf_frag_size) >= 1) {
938 m1 = m_split(m, length, MB_DONTWAIT);
939 if (m1 == NULL)
940 break;
941 m2 = m;
942 while (m2->m_next != NULL)
943 m2 = m2->m_next;
944 m2->m_next = m1;
945 }
946 m->m_pkthdr.len = tmp;
947 }
948 #endif
949
950 #ifdef MPLS
951 if (!mpls_output_process(m, ro->ro_rt))
952 goto done;
953 #endif
954 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
955 ro->ro_rt);
956 goto done;
957 }
958
959 if (ip->ip_off & IP_DF) {
960 error = EMSGSIZE;
961 /*
962 * This case can happen if the user changed the MTU
963 * of an interface after enabling IP on it. Because
964 * most netifs don't keep track of routes pointing to
965 * them, there is no way for one to update all its
966 * routes when the MTU is changed.
967 */
968 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) &&
969 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) &&
970 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) {
971 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
972 }
973 ipstat.ips_cantfrag++;
974 goto bad;
975 }
976
977 /*
978 * Too large for interface; fragment if possible. If successful,
979 * on return, m will point to a list of packets to be sent.
980 */
981 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum);
982 if (error)
983 goto bad;
984 for (; m; m = m0) {
985 m0 = m->m_nextpkt;
986 m->m_nextpkt = NULL;
987 #ifdef IPSEC
988 /* clean ipsec history once it goes out of the node */
989 ipsec_delaux(m);
990 #endif
991 if (error == 0) {
992 /* Record statistics for this interface address. */
993 if (ia != NULL) {
994 ia->ia_ifa.if_opackets++;
995 ia->ia_ifa.if_obytes += m->m_pkthdr.len;
996 }
997 #ifdef MPLS
998 if (!mpls_output_process(m, ro->ro_rt))
999 continue;
1000 #endif
1001 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
1002 ro->ro_rt);
1003 } else {
1004 m_freem(m);
1005 }
1006 }
1007
1008 if (error == 0)
1009 ipstat.ips_fragmented++;
1010
1011 done:
1012 if (ro == &iproute && ro->ro_rt != NULL) {
1013 RTFREE(ro->ro_rt);
1014 ro->ro_rt = NULL;
1015 }
1016 #ifdef IPSEC
1017 if (sp != NULL) {
1018 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1019 kprintf("DP ip_output call free SP:%p\n", sp));
1020 key_freesp(sp);
1021 }
1022 #endif
1023 #ifdef FAST_IPSEC
1024 if (sp != NULL)
1025 KEY_FREESP(&sp);
1026 #endif
1027 return (error);
1028 bad:
1029 m_freem(m);
1030 goto done;
1031 }
1032
1033 /*
1034 * Create a chain of fragments which fit the given mtu. m_frag points to the
1035 * mbuf to be fragmented; on return it points to the chain with the fragments.
1036 * Return 0 if no error. If error, m_frag may contain a partially built
1037 * chain of fragments that should be freed by the caller.
1038 *
1039 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
1040 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
1041 */
1042 int
1043 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
1044 u_long if_hwassist_flags, int sw_csum)
1045 {
1046 int error = 0;
1047 int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
1048 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
1049 int off;
1050 struct mbuf *m0 = *m_frag; /* the original packet */
1051 int firstlen;
1052 struct mbuf **mnext;
1053 int nfrags;
1054
1055 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */
1056 ipstat.ips_cantfrag++;
1057 return EMSGSIZE;
1058 }
1059
1060 /*
1061 * Must be able to put at least 8 bytes per fragment.
1062 */
1063 if (len < 8)
1064 return EMSGSIZE;
1065
1066 /*
1067 * If the interface will not calculate checksums on
1068 * fragmented packets, then do it here.
1069 */
1070 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) &&
1071 !(if_hwassist_flags & CSUM_IP_FRAGS)) {
1072 in_delayed_cksum(m0);
1073 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1074 }
1075
1076 if (len > PAGE_SIZE) {
1077 /*
1078 * Fragment large datagrams such that each segment
1079 * contains a multiple of PAGE_SIZE amount of data,
1080 * plus headers. This enables a receiver to perform
1081 * page-flipping zero-copy optimizations.
1082 *
1083 * XXX When does this help given that sender and receiver
1084 * could have different page sizes, and also mtu could
1085 * be less than the receiver's page size ?
1086 */
1087 int newlen;
1088 struct mbuf *m;
1089
1090 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next)
1091 off += m->m_len;
1092
1093 /*
1094 * firstlen (off - hlen) must be aligned on an
1095 * 8-byte boundary
1096 */
1097 if (off < hlen)
1098 goto smart_frag_failure;
1099 off = ((off - hlen) & ~7) + hlen;
1100 newlen = (~PAGE_MASK) & mtu;
1101 if ((newlen + sizeof(struct ip)) > mtu) {
1102 /* we failed, go back the default */
1103 smart_frag_failure:
1104 newlen = len;
1105 off = hlen + len;
1106 }
1107 len = newlen;
1108
1109 } else {
1110 off = hlen + len;
1111 }
1112
1113 firstlen = off - hlen;
1114 mnext = &m0->m_nextpkt; /* pointer to next packet */
1115
1116 /*
1117 * Loop through length of segment after first fragment,
1118 * make new header and copy data of each part and link onto chain.
1119 * Here, m0 is the original packet, m is the fragment being created.
1120 * The fragments are linked off the m_nextpkt of the original
1121 * packet, which after processing serves as the first fragment.
1122 */
1123 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) {
1124 struct ip *mhip; /* ip header on the fragment */
1125 struct mbuf *m;
1126 int mhlen = sizeof(struct ip);
1127
1128 MGETHDR(m, MB_DONTWAIT, MT_HEADER);
1129 if (m == NULL) {
1130 error = ENOBUFS;
1131 ipstat.ips_odropped++;
1132 goto done;
1133 }
1134 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
1135 /*
1136 * In the first mbuf, leave room for the link header, then
1137 * copy the original IP header including options. The payload
1138 * goes into an additional mbuf chain returned by m_copy().
1139 */
1140 m->m_data += max_linkhdr;
1141 mhip = mtod(m, struct ip *);
1142 *mhip = *ip;
1143 if (hlen > sizeof(struct ip)) {
1144 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip);
1145 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2);
1146 }
1147 m->m_len = mhlen;
1148 /* XXX do we need to add ip->ip_off below ? */
1149 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
1150 if (off + len >= ip->ip_len) { /* last fragment */
1151 len = ip->ip_len - off;
1152 m->m_flags |= M_LASTFRAG;
1153 } else
1154 mhip->ip_off |= IP_MF;
1155 mhip->ip_len = htons((u_short)(len + mhlen));
1156 m->m_next = m_copy(m0, off, len);
1157 if (m->m_next == NULL) { /* copy failed */
1158 m_free(m);
1159 error = ENOBUFS; /* ??? */
1160 ipstat.ips_odropped++;
1161 goto done;
1162 }
1163 m->m_pkthdr.len = mhlen + len;
1164 m->m_pkthdr.rcvif = (struct ifnet *)NULL;
1165 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
1166 mhip->ip_off = htons(mhip->ip_off);
1167 mhip->ip_sum = 0;
1168 if (sw_csum & CSUM_DELAY_IP)
1169 mhip->ip_sum = in_cksum(m, mhlen);
1170 *mnext = m;
1171 mnext = &m->m_nextpkt;
1172 }
1173 ipstat.ips_ofragments += nfrags;
1174
1175 /* set first marker for fragment chain */
1176 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1177 m0->m_pkthdr.csum_data = nfrags;
1178
1179 /*
1180 * Update first fragment by trimming what's been copied out
1181 * and updating header.
1182 */
1183 m_adj(m0, hlen + firstlen - ip->ip_len);
1184 m0->m_pkthdr.len = hlen + firstlen;
1185 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1186 ip->ip_off |= IP_MF;
1187 ip->ip_off = htons(ip->ip_off);
1188 ip->ip_sum = 0;
1189 if (sw_csum & CSUM_DELAY_IP)
1190 ip->ip_sum = in_cksum(m0, hlen);
1191
1192 done:
1193 *m_frag = m0;
1194 return error;
1195 }
1196
1197 void
1198 in_delayed_cksum(struct mbuf *m)
1199 {
1200 struct ip *ip;
1201 u_short csum, offset;
1202
1203 ip = mtod(m, struct ip *);
1204 offset = IP_VHL_HL(ip->ip_vhl) << 2 ;
1205 csum = in_cksum_skip(m, ip->ip_len, offset);
1206 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
1207 csum = 0xffff;
1208 offset += m->m_pkthdr.csum_data; /* checksum offset */
1209
1210 if (offset + sizeof(u_short) > m->m_len) {
1211 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n",
1212 m->m_len, offset, ip->ip_p);
1213 /*
1214 * XXX
1215 * this shouldn't happen, but if it does, the
1216 * correct behavior may be to insert the checksum
1217 * in the existing chain instead of rearranging it.
1218 */
1219 m = m_pullup(m, offset + sizeof(u_short));
1220 }
1221 *(u_short *)(m->m_data + offset) = csum;
1222 }
1223
1224 /*
1225 * Insert IP options into preformed packet.
1226 * Adjust IP destination as required for IP source routing,
1227 * as indicated by a non-zero in_addr at the start of the options.
1228 *
1229 * XXX This routine assumes that the packet has no options in place.
1230 */
1231 static struct mbuf *
1232 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen)
1233 {
1234 struct ipoption *p = mtod(opt, struct ipoption *);
1235 struct mbuf *n;
1236 struct ip *ip = mtod(m, struct ip *);
1237 unsigned optlen;
1238
1239 optlen = opt->m_len - sizeof p->ipopt_dst;
1240 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) {
1241 *phlen = 0;
1242 return (m); /* XXX should fail */
1243 }
1244 if (p->ipopt_dst.s_addr)
1245 ip->ip_dst = p->ipopt_dst;
1246 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
1247 MGETHDR(n, MB_DONTWAIT, MT_HEADER);
1248 if (n == NULL) {
1249 *phlen = 0;
1250 return (m);
1251 }
1252 n->m_pkthdr.rcvif = (struct ifnet *)NULL;
1253 n->m_pkthdr.len = m->m_pkthdr.len + optlen;
1254 m->m_len -= sizeof(struct ip);
1255 m->m_data += sizeof(struct ip);
1256 n->m_next = m;
1257 m = n;
1258 m->m_len = optlen + sizeof(struct ip);
1259 m->m_data += max_linkhdr;
1260 memcpy(mtod(m, void *), ip, sizeof(struct ip));
1261 } else {
1262 m->m_data -= optlen;
1263 m->m_len += optlen;
1264 m->m_pkthdr.len += optlen;
1265 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip));
1266 }
1267 ip = mtod(m, struct ip *);
1268 bcopy(p->ipopt_list, ip + 1, optlen);
1269 *phlen = sizeof(struct ip) + optlen;
1270 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2);
1271 ip->ip_len += optlen;
1272 return (m);
1273 }
1274
1275 /*
1276 * Copy options from ip to jp,
1277 * omitting those not copied during fragmentation.
1278 */
1279 int
1280 ip_optcopy(struct ip *ip, struct ip *jp)
1281 {
1282 u_char *cp, *dp;
1283 int opt, optlen, cnt;
1284
1285 cp = (u_char *)(ip + 1);
1286 dp = (u_char *)(jp + 1);
1287 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
1288 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1289 opt = cp[0];
1290 if (opt == IPOPT_EOL)
1291 break;
1292 if (opt == IPOPT_NOP) {
1293 /* Preserve for IP mcast tunnel's LSRR alignment. */
1294 *dp++ = IPOPT_NOP;
1295 optlen = 1;
1296 continue;
1297 }
1298
1299 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp,
1300 ("ip_optcopy: malformed ipv4 option"));
1301 optlen = cp[IPOPT_OLEN];
1302 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt,
1303 ("ip_optcopy: malformed ipv4 option"));
1304
1305 /* bogus lengths should have been caught by ip_dooptions */
1306 if (optlen > cnt)
1307 optlen = cnt;
1308 if (IPOPT_COPIED(opt)) {
1309 bcopy(cp, dp, optlen);
1310 dp += optlen;
1311 }
1312 }
1313 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
1314 *dp++ = IPOPT_EOL;
1315 return (optlen);
1316 }
1317
1318 /*
1319 * IP socket option processing.
1320 */
1321 int
1322 ip_ctloutput(struct socket *so, struct sockopt *sopt)
1323 {
1324 struct inpcb *inp = so->so_pcb;
1325 int error, optval;
1326
1327 error = optval = 0;
1328 if (sopt->sopt_level != IPPROTO_IP) {
1329 return (EINVAL);
1330 }
1331
1332 switch (sopt->sopt_dir) {
1333 case SOPT_SET:
1334 switch (sopt->sopt_name) {
1335 case IP_OPTIONS:
1336 #ifdef notyet
1337 case IP_RETOPTS:
1338 #endif
1339 {
1340 struct mbuf *m;
1341 if (sopt->sopt_valsize > MLEN) {
1342 error = EMSGSIZE;
1343 break;
1344 }
1345 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER);
1346 if (m == NULL) {
1347 error = ENOBUFS;
1348 break;
1349 }
1350 m->m_len = sopt->sopt_valsize;
1351 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len,
1352 m->m_len);
1353 return (ip_pcbopts(sopt->sopt_name, &inp->inp_options,
1354 m));
1355 }
1356
1357 case IP_TOS:
1358 case IP_TTL:
1359 case IP_MINTTL:
1360 case IP_RECVOPTS:
1361 case IP_RECVRETOPTS:
1362 case IP_RECVDSTADDR:
1363 case IP_RECVIF:
1364 case IP_RECVTTL:
1365 case IP_FAITH:
1366 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1367 sizeof optval);
1368 if (error)
1369 break;
1370 switch (sopt->sopt_name) {
1371 case IP_TOS:
1372 inp->inp_ip_tos = optval;
1373 break;
1374
1375 case IP_TTL:
1376 inp->inp_ip_ttl = optval;
1377 break;
1378 case IP_MINTTL:
1379 if (optval > 0 && optval <= MAXTTL)
1380 inp->inp_ip_minttl = optval;
1381 else
1382 error = EINVAL;
1383 break;
1384 #define OPTSET(bit) \
1385 if (optval) \
1386 inp->inp_flags |= bit; \
1387 else \
1388 inp->inp_flags &= ~bit;
1389
1390 case IP_RECVOPTS:
1391 OPTSET(INP_RECVOPTS);
1392 break;
1393
1394 case IP_RECVRETOPTS:
1395 OPTSET(INP_RECVRETOPTS);
1396 break;
1397
1398 case IP_RECVDSTADDR:
1399 OPTSET(INP_RECVDSTADDR);
1400 break;
1401
1402 case IP_RECVIF:
1403 OPTSET(INP_RECVIF);
1404 break;
1405
1406 case IP_RECVTTL:
1407 OPTSET(INP_RECVTTL);
1408 break;
1409
1410 case IP_FAITH:
1411 OPTSET(INP_FAITH);
1412 break;
1413 }
1414 break;
1415 #undef OPTSET
1416
1417 case IP_MULTICAST_IF:
1418 case IP_MULTICAST_VIF:
1419 case IP_MULTICAST_TTL:
1420 case IP_MULTICAST_LOOP:
1421 case IP_ADD_MEMBERSHIP:
1422 case IP_DROP_MEMBERSHIP:
1423 error = ip_setmoptions(sopt, &inp->inp_moptions);
1424 break;
1425
1426 case IP_PORTRANGE:
1427 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1428 sizeof optval);
1429 if (error)
1430 break;
1431
1432 switch (optval) {
1433 case IP_PORTRANGE_DEFAULT:
1434 inp->inp_flags &= ~(INP_LOWPORT);
1435 inp->inp_flags &= ~(INP_HIGHPORT);
1436 break;
1437
1438 case IP_PORTRANGE_HIGH:
1439 inp->inp_flags &= ~(INP_LOWPORT);
1440 inp->inp_flags |= INP_HIGHPORT;
1441 break;
1442
1443 case IP_PORTRANGE_LOW:
1444 inp->inp_flags &= ~(INP_HIGHPORT);
1445 inp->inp_flags |= INP_LOWPORT;
1446 break;
1447
1448 default:
1449 error = EINVAL;
1450 break;
1451 }
1452 break;
1453
1454 #if defined(IPSEC) || defined(FAST_IPSEC)
1455 case IP_IPSEC_POLICY:
1456 {
1457 caddr_t req;
1458 size_t len = 0;
1459 int priv;
1460 struct mbuf *m;
1461 int optname;
1462
1463 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1464 break;
1465 soopt_to_mbuf(sopt, m);
1466 priv = (sopt->sopt_td != NULL &&
1467 suser(sopt->sopt_td) != 0) ? 0 : 1;
1468 req = mtod(m, caddr_t);
1469 len = m->m_len;
1470 optname = sopt->sopt_name;
1471 error = ipsec4_set_policy(inp, optname, req, len, priv);
1472 m_freem(m);
1473 break;
1474 }
1475 #endif /*IPSEC*/
1476
1477 default:
1478 error = ENOPROTOOPT;
1479 break;
1480 }
1481 break;
1482
1483 case SOPT_GET:
1484 switch (sopt->sopt_name) {
1485 case IP_OPTIONS:
1486 case IP_RETOPTS:
1487 if (inp->inp_options)
1488 soopt_from_kbuf(sopt, mtod(inp->inp_options,
1489 char *),
1490 inp->inp_options->m_len);
1491 else
1492 sopt->sopt_valsize = 0;
1493 break;
1494
1495 case IP_TOS:
1496 case IP_TTL:
1497 case IP_MINTTL:
1498 case IP_RECVOPTS:
1499 case IP_RECVRETOPTS:
1500 case IP_RECVDSTADDR:
1501 case IP_RECVTTL:
1502 case IP_RECVIF:
1503 case IP_PORTRANGE:
1504 case IP_FAITH:
1505 switch (sopt->sopt_name) {
1506
1507 case IP_TOS:
1508 optval = inp->inp_ip_tos;
1509 break;
1510
1511 case IP_TTL:
1512 optval = inp->inp_ip_ttl;
1513 break;
1514 case IP_MINTTL:
1515 optval = inp->inp_ip_minttl;
1516 break;
1517
1518 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1519
1520 case IP_RECVOPTS:
1521 optval = OPTBIT(INP_RECVOPTS);
1522 break;
1523
1524 case IP_RECVRETOPTS:
1525 optval = OPTBIT(INP_RECVRETOPTS);
1526 break;
1527
1528 case IP_RECVDSTADDR:
1529 optval = OPTBIT(INP_RECVDSTADDR);
1530 break;
1531
1532 case IP_RECVTTL:
1533 optval = OPTBIT(INP_RECVTTL);
1534 break;
1535
1536 case IP_RECVIF:
1537 optval = OPTBIT(INP_RECVIF);
1538 break;
1539
1540 case IP_PORTRANGE:
1541 if (inp->inp_flags & INP_HIGHPORT)
1542 optval = IP_PORTRANGE_HIGH;
1543 else if (inp->inp_flags & INP_LOWPORT)
1544 optval = IP_PORTRANGE_LOW;
1545 else
1546 optval = 0;
1547 break;
1548
1549 case IP_FAITH:
1550 optval = OPTBIT(INP_FAITH);
1551 break;
1552 }
1553 soopt_from_kbuf(sopt, &optval, sizeof optval);
1554 break;
1555
1556 case IP_MULTICAST_IF:
1557 case IP_MULTICAST_VIF:
1558 case IP_MULTICAST_TTL:
1559 case IP_MULTICAST_LOOP:
1560 case IP_ADD_MEMBERSHIP:
1561 case IP_DROP_MEMBERSHIP:
1562 error = ip_getmoptions(sopt, inp->inp_moptions);
1563 break;
1564
1565 #if defined(IPSEC) || defined(FAST_IPSEC)
1566 case IP_IPSEC_POLICY:
1567 {
1568 struct mbuf *m = NULL;
1569 caddr_t req = NULL;
1570 size_t len = 0;
1571
1572 if (m != NULL) {
1573 req = mtod(m, caddr_t);
1574 len = m->m_len;
1575 }
1576 error = ipsec4_get_policy(so->so_pcb, req, len, &m);
1577 if (error == 0)
1578 error = soopt_from_mbuf(sopt, m); /* XXX */
1579 if (error == 0)
1580 m_freem(m);
1581 break;
1582 }
1583 #endif /*IPSEC*/
1584
1585 default:
1586 error = ENOPROTOOPT;
1587 break;
1588 }
1589 break;
1590 }
1591 return (error);
1592 }
1593
1594 /*
1595 * Set up IP options in pcb for insertion in output packets.
1596 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1597 * with destination address if source routed.
1598 */
1599 static int
1600 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m)
1601 {
1602 int cnt, optlen;
1603 u_char *cp;
1604 u_char opt;
1605
1606 /* turn off any old options */
1607 if (*pcbopt)
1608 m_free(*pcbopt);
1609 *pcbopt = 0;
1610 if (m == NULL || m->m_len == 0) {
1611 /*
1612 * Only turning off any previous options.
1613 */
1614 if (m != NULL)
1615 m_free(m);
1616 return (0);
1617 }
1618
1619 if (m->m_len % sizeof(int32_t))
1620 goto bad;
1621 /*
1622 * IP first-hop destination address will be stored before
1623 * actual options; move other options back
1624 * and clear it when none present.
1625 */
1626 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
1627 goto bad;
1628 cnt = m->m_len;
1629 m->m_len += sizeof(struct in_addr);
1630 cp = mtod(m, u_char *) + sizeof(struct in_addr);
1631 ovbcopy(mtod(m, caddr_t), cp, cnt);
1632 bzero(mtod(m, caddr_t), sizeof(struct in_addr));
1633
1634 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1635 opt = cp[IPOPT_OPTVAL];
1636 if (opt == IPOPT_EOL)
1637 break;
1638 if (opt == IPOPT_NOP)
1639 optlen = 1;
1640 else {
1641 if (cnt < IPOPT_OLEN + sizeof *cp)
1642 goto bad;
1643 optlen = cp[IPOPT_OLEN];
1644 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt)
1645 goto bad;
1646 }
1647 switch (opt) {
1648
1649 default:
1650 break;
1651
1652 case IPOPT_LSRR:
1653 case IPOPT_SSRR:
1654 /*
1655 * user process specifies route as:
1656 * ->A->B->C->D
1657 * D must be our final destination (but we can't
1658 * check that since we may not have connected yet).
1659 * A is first hop destination, which doesn't appear in
1660 * actual IP option, but is stored before the options.
1661 */
1662 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
1663 goto bad;
1664 m->m_len -= sizeof(struct in_addr);
1665 cnt -= sizeof(struct in_addr);
1666 optlen -= sizeof(struct in_addr);
1667 cp[IPOPT_OLEN] = optlen;
1668 /*
1669 * Move first hop before start of options.
1670 */
1671 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
1672 sizeof(struct in_addr));
1673 /*
1674 * Then copy rest of options back
1675 * to close up the deleted entry.
1676 */
1677 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr),
1678 &cp[IPOPT_OFFSET+1],
1679 cnt - (IPOPT_MINOFF - 1));
1680 break;
1681 }
1682 }
1683 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
1684 goto bad;
1685 *pcbopt = m;
1686 return (0);
1687
1688 bad:
1689 m_free(m);
1690 return (EINVAL);
1691 }
1692
1693 /*
1694 * XXX
1695 * The whole multicast option thing needs to be re-thought.
1696 * Several of these options are equally applicable to non-multicast
1697 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1698 * standard option (IP_TTL).
1699 */
1700
1701 /*
1702 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1703 */
1704 static struct ifnet *
1705 ip_multicast_if(struct in_addr *a, int *ifindexp)
1706 {
1707 int ifindex;
1708 struct ifnet *ifp;
1709
1710 if (ifindexp)
1711 *ifindexp = 0;
1712 if (ntohl(a->s_addr) >> 24 == 0) {
1713 ifindex = ntohl(a->s_addr) & 0xffffff;
1714 if (ifindex < 0 || if_index < ifindex)
1715 return NULL;
1716 ifp = ifindex2ifnet[ifindex];
1717 if (ifindexp)
1718 *ifindexp = ifindex;
1719 } else {
1720 ifp = INADDR_TO_IFP(a);
1721 }
1722 return ifp;
1723 }
1724
1725 /*
1726 * Set the IP multicast options in response to user setsockopt().
1727 */
1728 static int
1729 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop)
1730 {
1731 int error = 0;
1732 int i;
1733 struct in_addr addr;
1734 struct ip_mreq mreq;
1735 struct ifnet *ifp;
1736 struct ip_moptions *imo = *imop;
1737 int ifindex;
1738
1739 if (imo == NULL) {
1740 /*
1741 * No multicast option buffer attached to the pcb;
1742 * allocate one and initialize to default values.
1743 */
1744 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK);
1745
1746 *imop = imo;
1747 imo->imo_multicast_ifp = NULL;
1748 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1749 imo->imo_multicast_vif = -1;
1750 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1751 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
1752 imo->imo_num_memberships = 0;
1753 }
1754 switch (sopt->sopt_name) {
1755 /* store an index number for the vif you wanna use in the send */
1756 case IP_MULTICAST_VIF:
1757 if (legal_vif_num == 0) {
1758 error = EOPNOTSUPP;
1759 break;
1760 }
1761 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i);
1762 if (error)
1763 break;
1764 if (!legal_vif_num(i) && (i != -1)) {
1765 error = EINVAL;
1766 break;
1767 }
1768 imo->imo_multicast_vif = i;
1769 break;
1770
1771 case IP_MULTICAST_IF:
1772 /*
1773 * Select the interface for outgoing multicast packets.
1774 */
1775 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr);
1776 if (error)
1777 break;
1778
1779 /*
1780 * INADDR_ANY is used to remove a previous selection.
1781 * When no interface is selected, a default one is
1782 * chosen every time a multicast packet is sent.
1783 */
1784 if (addr.s_addr == INADDR_ANY) {
1785 imo->imo_multicast_ifp = NULL;
1786 break;
1787 }
1788 /*
1789 * The selected interface is identified by its local
1790 * IP address. Find the interface and confirm that
1791 * it supports multicasting.
1792 */
1793 crit_enter();
1794 ifp = ip_multicast_if(&addr, &ifindex);
1795 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1796 crit_exit();
1797 error = EADDRNOTAVAIL;
1798 break;
1799 }
1800 imo->imo_multicast_ifp = ifp;
1801 if (ifindex)
1802 imo->imo_multicast_addr = addr;
1803 else
1804 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1805 crit_exit();
1806 break;
1807
1808 case IP_MULTICAST_TTL:
1809 /*
1810 * Set the IP time-to-live for outgoing multicast packets.
1811 * The original multicast API required a char argument,
1812 * which is inconsistent with the rest of the socket API.
1813 * We allow either a char or an int.
1814 */
1815 if (sopt->sopt_valsize == 1) {
1816 u_char ttl;
1817 error = soopt_to_kbuf(sopt, &ttl, 1, 1);
1818 if (error)
1819 break;
1820 imo->imo_multicast_ttl = ttl;
1821 } else {
1822 u_int ttl;
1823 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl);
1824 if (error)
1825 break;
1826 if (ttl > 255)
1827 error = EINVAL;
1828 else
1829 imo->imo_multicast_ttl = ttl;
1830 }
1831 break;
1832
1833 case IP_MULTICAST_LOOP:
1834 /*
1835 * Set the loopback flag for outgoing multicast packets.
1836 * Must be zero or one. The original multicast API required a
1837 * char argument, which is inconsistent with the rest
1838 * of the socket API. We allow either a char or an int.
1839 */
1840 if (sopt->sopt_valsize == 1) {
1841 u_char loop;
1842
1843 error = soopt_to_kbuf(sopt, &loop, 1, 1);
1844 if (error)
1845 break;
1846 imo->imo_multicast_loop = !!loop;
1847 } else {
1848 u_int loop;
1849
1850 error = soopt_to_kbuf(sopt, &loop, sizeof loop,
1851 sizeof loop);
1852 if (error)
1853 break;
1854 imo->imo_multicast_loop = !!loop;
1855 }
1856 break;
1857
1858 case IP_ADD_MEMBERSHIP:
1859 /*
1860 * Add a multicast group membership.
1861 * Group must be a valid IP multicast address.
1862 */
1863 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1864 if (error)
1865 break;
1866
1867 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1868 error = EINVAL;
1869 break;
1870 }
1871 crit_enter();
1872 /*
1873 * If no interface address was provided, use the interface of
1874 * the route to the given multicast address.
1875 */
1876 if (mreq.imr_interface.s_addr == INADDR_ANY) {
1877 struct sockaddr_in dst;
1878 struct rtentry *rt;
1879
1880 bzero(&dst, sizeof(struct sockaddr_in));
1881 dst.sin_len = sizeof(struct sockaddr_in);
1882 dst.sin_family = AF_INET;
1883 dst.sin_addr = mreq.imr_multiaddr;
1884 rt = rtlookup((struct sockaddr *)&dst);
1885 if (rt == NULL) {
1886 error = EADDRNOTAVAIL;
1887 crit_exit();
1888 break;
1889 }
1890 --rt->rt_refcnt;
1891 ifp = rt->rt_ifp;
1892 } else {
1893 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1894 }
1895
1896 /*
1897 * See if we found an interface, and confirm that it
1898 * supports multicast.
1899 */
1900 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1901 error = EADDRNOTAVAIL;
1902 crit_exit();
1903 break;
1904 }
1905 /*
1906 * See if the membership already exists or if all the
1907 * membership slots are full.
1908 */
1909 for (i = 0; i < imo->imo_num_memberships; ++i) {
1910 if (imo->imo_membership[i]->inm_ifp == ifp &&
1911 imo->imo_membership[i]->inm_addr.s_addr
1912 == mreq.imr_multiaddr.s_addr)
1913 break;
1914 }
1915 if (i < imo->imo_num_memberships) {
1916 error = EADDRINUSE;
1917 crit_exit();
1918 break;
1919 }
1920 if (i == IP_MAX_MEMBERSHIPS) {
1921 error = ETOOMANYREFS;
1922 crit_exit();
1923 break;
1924 }
1925 /*
1926 * Everything looks good; add a new record to the multicast
1927 * address list for the given interface.
1928 */
1929 if ((imo->imo_membership[i] =
1930 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) {
1931 error = ENOBUFS;
1932 crit_exit();
1933 break;
1934 }
1935 ++imo->imo_num_memberships;
1936 crit_exit();
1937 break;
1938
1939 case IP_DROP_MEMBERSHIP:
1940 /*
1941 * Drop a multicast group membership.
1942 * Group must be a valid IP multicast address.
1943 */
1944 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1945 if (error)
1946 break;
1947
1948 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1949 error = EINVAL;
1950 break;
1951 }
1952
1953 crit_enter();
1954 /*
1955 * If an interface address was specified, get a pointer
1956 * to its ifnet structure.
1957 */
1958 if (mreq.imr_interface.s_addr == INADDR_ANY)
1959 ifp = NULL;
1960 else {
1961 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1962 if (ifp == NULL) {
1963 error = EADDRNOTAVAIL;
1964 crit_exit();
1965 break;
1966 }
1967 }
1968 /*
1969 * Find the membership in the membership array.
1970 */
1971 for (i = 0; i < imo->imo_num_memberships; ++i) {
1972 if ((ifp == NULL ||
1973 imo->imo_membership[i]->inm_ifp == ifp) &&
1974 imo->imo_membership[i]->inm_addr.s_addr ==
1975 mreq.imr_multiaddr.s_addr)
1976 break;
1977 }
1978 if (i == imo->imo_num_memberships) {
1979 error = EADDRNOTAVAIL;
1980 crit_exit();
1981 break;
1982 }
1983 /*
1984 * Give up the multicast address record to which the
1985 * membership points.
1986 */
1987 in_delmulti(imo->imo_membership[i]);
1988 /*
1989 * Remove the gap in the membership array.
1990 */
1991 for (++i; i < imo->imo_num_memberships; ++i)
1992 imo->imo_membership[i-1] = imo->imo_membership[i];
1993 --imo->imo_num_memberships;
1994 crit_exit();
1995 break;
1996
1997 default:
1998 error = EOPNOTSUPP;
1999 break;
2000 }
2001
2002 /*
2003 * If all options have default values, no need to keep the mbuf.
2004 */
2005 if (imo->imo_multicast_ifp == NULL &&
2006 imo->imo_multicast_vif == -1 &&
2007 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
2008 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
2009 imo->imo_num_memberships == 0) {
2010 kfree(*imop, M_IPMOPTS);
2011 *imop = NULL;
2012 }
2013
2014 return (error);
2015 }
2016
2017 /*
2018 * Return the IP multicast options in response to user getsockopt().
2019 */
2020 static int
2021 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo)
2022 {
2023 struct in_addr addr;
2024 struct in_ifaddr *ia;
2025 int error, optval;
2026 u_char coptval;
2027
2028 error = 0;
2029 switch (sopt->sopt_name) {
2030 case IP_MULTICAST_VIF:
2031 if (imo != NULL)
2032 optval = imo->imo_multicast_vif;
2033 else
2034 optval = -1;
2035 soopt_from_kbuf(sopt, &optval, sizeof optval);
2036 break;
2037
2038 case IP_MULTICAST_IF:
2039 if (imo == NULL || imo->imo_multicast_ifp == NULL)
2040 addr.s_addr = INADDR_ANY;
2041 else if (imo->imo_multicast_addr.s_addr) {
2042 /* return the value user has set */
2043 addr = imo->imo_multicast_addr;
2044 } else {
2045 ia = IFP_TO_IA(imo->imo_multicast_ifp);
2046 addr.s_addr = (ia == NULL) ? INADDR_ANY
2047 : IA_SIN(ia)->sin_addr.s_addr;
2048 }
2049 soopt_from_kbuf(sopt, &addr, sizeof addr);
2050 break;
2051
2052 case IP_MULTICAST_TTL:
2053 if (imo == NULL)
2054 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
2055 else
2056 optval = coptval = imo->imo_multicast_ttl;
2057 if (sopt->sopt_valsize == 1)
2058 soopt_from_kbuf(sopt, &coptval, 1);
2059 else
2060 soopt_from_kbuf(sopt, &optval, sizeof optval);
2061 break;
2062
2063 case IP_MULTICAST_LOOP:
2064 if (imo == NULL)
2065 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
2066 else
2067 optval = coptval = imo->imo_multicast_loop;
2068 if (sopt->sopt_valsize == 1)
2069 soopt_from_kbuf(sopt, &coptval, 1);
2070 else
2071 soopt_from_kbuf(sopt, &optval, sizeof optval);
2072 break;
2073
2074 default:
2075 error = ENOPROTOOPT;
2076 break;
2077 }
2078 return (error);
2079 }
2080
2081 /*
2082 * Discard the IP multicast options.
2083 */
2084 void
2085 ip_freemoptions(struct ip_moptions *imo)
2086 {
2087 int i;
2088
2089 if (imo != NULL) {
2090 for (i = 0; i < imo->imo_num_memberships; ++i)
2091 in_delmulti(imo->imo_membership[i]);
2092 kfree(imo, M_IPMOPTS);
2093 }
2094 }
2095
2096 /*
2097 * Routine called from ip_output() to loop back a copy of an IP multicast
2098 * packet to the input queue of a specified interface. Note that this
2099 * calls the output routine of the loopback "driver", but with an interface
2100 * pointer that might NOT be a loopback interface -- evil, but easier than
2101 * replicating that code here.
2102 */
2103 static void
2104 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst,
2105 int hlen)
2106 {
2107 struct ip *ip;
2108 struct mbuf *copym;
2109
2110 copym = m_copypacket(m, MB_DONTWAIT);
2111 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
2112 copym = m_pullup(copym, hlen);
2113 if (copym != NULL) {
2114 /*
2115 * if the checksum hasn't been computed, mark it as valid
2116 */
2117 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2118 in_delayed_cksum(copym);
2119 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
2120 copym->m_pkthdr.csum_flags |=
2121 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2122 copym->m_pkthdr.csum_data = 0xffff;
2123 }
2124 /*
2125 * We don't bother to fragment if the IP length is greater
2126 * than the interface's MTU. Can this possibly matter?
2127 */
2128 ip = mtod(copym, struct ip *);
2129 ip->ip_len = htons(ip->ip_len);
2130 ip->ip_off = htons(ip->ip_off);
2131 ip->ip_sum = 0;
2132 if (ip->ip_vhl == IP_VHL_BORING) {
2133 ip->ip_sum = in_cksum_hdr(ip);
2134 } else {
2135 ip->ip_sum = in_cksum(copym, hlen);
2136 }
2137 /*
2138 * NB:
2139 * It's not clear whether there are any lingering
2140 * reentrancy problems in other areas which might
2141 * be exposed by using ip_input directly (in
2142 * particular, everything which modifies the packet
2143 * in-place). Yet another option is using the
2144 * protosw directly to deliver the looped back
2145 * packet. For the moment, we'll err on the side
2146 * of safety by using if_simloop().
2147 */
2148 #if 1 /* XXX */
2149 if (dst->sin_family != AF_INET) {
2150 kprintf("ip_mloopback: bad address family %d\n",
2151 dst->sin_family);
2152 dst->sin_family = AF_INET;
2153 }
2154 #endif
2155
2156 #ifdef notdef
2157 copym->m_pkthdr.rcvif = ifp;
2158 ip_input(copym);
2159 #else
2160 if_simloop(ifp, copym, dst->sin_family, 0);
2161 #endif
2162 }
2163 }
DragonFly BSD