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 */
32
33 #define _IP_VHL
34
35 #include "opt_ipdn.h"
36 #include "opt_ipdivert.h"
37 #include "opt_ipsec.h"
38 #include "opt_mbuf_stress_test.h"
39 #include "opt_mpls.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/malloc.h>
45 #include <sys/mbuf.h>
46 #include <sys/protosw.h>
47 #include <sys/socket.h>
48 #include <sys/socketvar.h>
49 #include <sys/proc.h>
50 #include <sys/priv.h>
51 #include <sys/sysctl.h>
52 #include <sys/in_cksum.h>
53 #include <sys/lock.h>
54
55 #include <sys/thread2.h>
56 #include <sys/mplock2.h>
57 #include <sys/msgport2.h>
58
59 #include <net/if.h>
60 #include <net/netisr.h>
61 #include <net/pfil.h>
62 #include <net/route.h>
63
64 #include <netinet/in.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/ip.h>
67 #include <netinet/in_pcb.h>
68 #include <netinet/in_var.h>
69 #include <netinet/ip_var.h>
70
71 #include <netproto/mpls/mpls_var.h>
72
73 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "internet multicast options");
74
75 #ifdef IPSEC
76 #include <netinet6/ipsec.h>
77 #include <netproto/key/key.h>
78 #ifdef IPSEC_DEBUG
79 #include <netproto/key/key_debug.h>
80 #else
81 #define KEYDEBUG(lev,arg)
82 #endif
83 #endif /*IPSEC*/
84
85 #ifdef FAST_IPSEC
86 #include <netproto/ipsec/ipsec.h>
87 #include <netproto/ipsec/xform.h>
88 #include <netproto/ipsec/key.h>
89 #endif /*FAST_IPSEC*/
90
91 #include <net/ipfw/ip_fw.h>
92 #include <net/dummynet/ip_dummynet.h>
93
94 #define print_ip(x, a, y) kprintf("%s %d.%d.%d.%d%s",\
95 x, (ntohl(a.s_addr)>>24)&0xFF,\
96 (ntohl(a.s_addr)>>16)&0xFF,\
97 (ntohl(a.s_addr)>>8)&0xFF,\
98 (ntohl(a.s_addr))&0xFF, y);
99
100 u_short ip_id;
101
102 #ifdef MBUF_STRESS_TEST
103 int mbuf_frag_size = 0;
104 SYSCTL_INT(_net_inet_ip, OID_AUTO, mbuf_frag_size, CTLFLAG_RW,
105 &mbuf_frag_size, 0, "Fragment outgoing mbufs to this size");
106 #endif
107
108 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *);
109 static struct ifnet *ip_multicast_if(struct in_addr *, int *);
110 static void ip_mloopback
111 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int);
112 static int ip_getmoptions
113 (struct sockopt *, struct ip_moptions *);
114 static int ip_pcbopts(int, struct mbuf **, struct mbuf *);
115 static int ip_setmoptions
116 (struct sockopt *, struct ip_moptions **);
117
118 int ip_optcopy(struct ip *, struct ip *);
119
120 extern struct protosw inetsw[];
121
122 static int
123 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst, int hlen)
124 {
125 struct in_ifaddr_container *iac;
126
127 /*
128 * We need to figure out if we have been forwarded to a local
129 * socket. If so, then we should somehow "loop back" to
130 * ip_input(), and get directed to the PCB as if we had received
131 * this packet. This is because it may be difficult to identify
132 * the packets you want to forward until they are being output
133 * and have selected an interface (e.g. locally initiated
134 * packets). If we used the loopback inteface, we would not be
135 * able to control what happens as the packet runs through
136 * ip_input() as it is done through a ISR.
137 */
138 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) {
139 /*
140 * If the addr to forward to is one of ours, we pretend
141 * to be the destination for this packet.
142 */
143 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr)
144 break;
145 }
146 if (iac != NULL) {
147 struct ip *ip;
148
149 if (m->m_pkthdr.rcvif == NULL)
150 m->m_pkthdr.rcvif = ifunit("lo0");
151 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
152 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID |
153 CSUM_PSEUDO_HDR;
154 m->m_pkthdr.csum_data = 0xffff;
155 }
156 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID;
157
158 /*
159 * Make sure that the IP header is in one mbuf,
160 * required by ip_input
161 */
162 if (m->m_len < hlen) {
163 m = m_pullup(m, hlen);
164 if (m == NULL) {
165 /* The packet was freed; we are done */
166 return 1;
167 }
168 }
169 ip = mtod(m, struct ip *);
170
171 ip->ip_len = htons(ip->ip_len);
172 ip->ip_off = htons(ip->ip_off);
173 ip_input(m);
174
175 return 1; /* The packet gets forwarded locally */
176 }
177 return 0;
178 }
179
180 /*
181 * IP output. The packet in mbuf chain m contains a skeletal IP
182 * header (with len, off, ttl, proto, tos, src, dst).
183 * The mbuf chain containing the packet will be freed.
184 * The mbuf opt, if present, will not be freed.
185 */
186 int
187 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro,
188 int flags, struct ip_moptions *imo, struct inpcb *inp)
189 {
190 struct ip *ip;
191 struct ifnet *ifp = NULL; /* keep compiler happy */
192 struct mbuf *m;
193 int hlen = sizeof(struct ip);
194 int len, error = 0;
195 struct sockaddr_in *dst = NULL; /* keep compiler happy */
196 struct in_ifaddr *ia = NULL;
197 int isbroadcast, sw_csum;
198 struct in_addr pkt_dst;
199 struct route iproute;
200 struct m_tag *mtag;
201 #ifdef IPSEC
202 struct secpolicy *sp = NULL;
203 struct socket *so = inp ? inp->inp_socket : NULL;
204 #endif
205 #ifdef FAST_IPSEC
206 struct secpolicy *sp = NULL;
207 struct tdb_ident *tdbi;
208 #endif /* FAST_IPSEC */
209 struct sockaddr_in *next_hop = NULL;
210 int src_was_INADDR_ANY = 0; /* as the name says... */
211
212 m = m0;
213 M_ASSERTPKTHDR(m);
214
215 if (ro == NULL) {
216 ro = &iproute;
217 bzero(ro, sizeof *ro);
218 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) {
219 if (flags & IP_DEBUGROUTE) {
220 panic("ip_output: rt rt_cpuid %d accessed on cpu %d\n",
221 ro->ro_rt->rt_cpuid, mycpuid);
222 }
223
224 /*
225 * XXX
226 * If the cached rtentry's owner CPU is not the current CPU,
227 * then don't touch the cached rtentry (remote free is too
228 * expensive in this context); just relocate the route.
229 */
230 ro = &iproute;
231 bzero(ro, sizeof *ro);
232 }
233
234 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
235 /* Next hop */
236 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
237 KKASSERT(mtag != NULL);
238 next_hop = m_tag_data(mtag);
239 }
240
241 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
242 struct dn_pkt *dn_pkt;
243
244 /* Extract info from dummynet tag */
245 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
246 KKASSERT(mtag != NULL);
247 dn_pkt = m_tag_data(mtag);
248
249 /*
250 * The packet was already tagged, so part of the
251 * processing was already done, and we need to go down.
252 * Get the calculated parameters from the tag.
253 */
254 ifp = dn_pkt->ifp;
255
256 KKASSERT(ro == &iproute);
257 *ro = dn_pkt->ro; /* structure copy */
258 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid);
259
260 dst = dn_pkt->dn_dst;
261 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) {
262 /* If 'dst' points into dummynet tag, adjust it */
263 dst = (struct sockaddr_in *)&(ro->ro_dst);
264 }
265
266 ip = mtod(m, struct ip *);
267 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ;
268 if (ro->ro_rt)
269 ia = ifatoia(ro->ro_rt->rt_ifa);
270 goto sendit;
271 }
272
273 if (opt) {
274 len = 0;
275 m = ip_insertoptions(m, opt, &len);
276 if (len != 0)
277 hlen = len;
278 }
279 ip = mtod(m, struct ip *);
280
281 /*
282 * Fill in IP header.
283 */
284 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) {
285 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2);
286 ip->ip_off &= IP_DF;
287 ip->ip_id = ip_newid();
288 ipstat.ips_localout++;
289 } else {
290 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
291 }
292
293 reroute:
294 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst;
295
296 dst = (struct sockaddr_in *)&ro->ro_dst;
297 /*
298 * If there is a cached route,
299 * check that it is to the same destination
300 * and is still up. If not, free it and try again.
301 * The address family should also be checked in case of sharing the
302 * cache with IPv6.
303 */
304 if (ro->ro_rt &&
305 (!(ro->ro_rt->rt_flags & RTF_UP) ||
306 dst->sin_family != AF_INET ||
307 dst->sin_addr.s_addr != pkt_dst.s_addr)) {
308 rtfree(ro->ro_rt);
309 ro->ro_rt = NULL;
310 }
311 if (ro->ro_rt == NULL) {
312 bzero(dst, sizeof *dst);
313 dst->sin_family = AF_INET;
314 dst->sin_len = sizeof *dst;
315 dst->sin_addr = pkt_dst;
316 }
317 /*
318 * If routing to interface only,
319 * short circuit routing lookup.
320 */
321 if (flags & IP_ROUTETOIF) {
322 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL &&
323 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) {
324 ipstat.ips_noroute++;
325 error = ENETUNREACH;
326 goto bad;
327 }
328 ifp = ia->ia_ifp;
329 ip->ip_ttl = 1;
330 isbroadcast = in_broadcast(dst->sin_addr, ifp);
331 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) &&
332 imo != NULL && imo->imo_multicast_ifp != NULL) {
333 /*
334 * Bypass the normal routing lookup for multicast
335 * packets if the interface is specified.
336 */
337 ifp = imo->imo_multicast_ifp;
338 ia = IFP_TO_IA(ifp);
339 isbroadcast = 0; /* fool gcc */
340 } else {
341 /*
342 * If this is the case, we probably don't want to allocate
343 * a protocol-cloned route since we didn't get one from the
344 * ULP. This lets TCP do its thing, while not burdening
345 * forwarding or ICMP with the overhead of cloning a route.
346 * Of course, we still want to do any cloning requested by
347 * the link layer, as this is probably required in all cases
348 * for correct operation (as it is for ARP).
349 */
350 if (ro->ro_rt == NULL)
351 rtalloc_ign(ro, RTF_PRCLONING);
352 if (ro->ro_rt == NULL) {
353 ipstat.ips_noroute++;
354 error = EHOSTUNREACH;
355 goto bad;
356 }
357 ia = ifatoia(ro->ro_rt->rt_ifa);
358 ifp = ro->ro_rt->rt_ifp;
359 ro->ro_rt->rt_use++;
360 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
361 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
362 if (ro->ro_rt->rt_flags & RTF_HOST)
363 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
364 else
365 isbroadcast = in_broadcast(dst->sin_addr, ifp);
366 }
367 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
368 m->m_flags |= M_MCAST;
369 /*
370 * IP destination address is multicast. Make sure "dst"
371 * still points to the address in "ro". (It may have been
372 * changed to point to a gateway address, above.)
373 */
374 dst = (struct sockaddr_in *)&ro->ro_dst;
375 /*
376 * See if the caller provided any multicast options
377 */
378 if (imo != NULL) {
379 ip->ip_ttl = imo->imo_multicast_ttl;
380 if (imo->imo_multicast_vif != -1) {
381 ip->ip_src.s_addr =
382 ip_mcast_src ?
383 ip_mcast_src(imo->imo_multicast_vif) :
384 INADDR_ANY;
385 }
386 } else {
387 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
388 }
389 /*
390 * Confirm that the outgoing interface supports multicast.
391 */
392 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
393 if (!(ifp->if_flags & IFF_MULTICAST)) {
394 ipstat.ips_noroute++;
395 error = ENETUNREACH;
396 goto bad;
397 }
398 }
399 /*
400 * If source address not specified yet, use address of the
401 * outgoing interface. In case, keep note we did that, so
402 * if the the firewall changes the next-hop causing the
403 * output interface to change, we can fix that.
404 */
405 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
406 /* Interface may have no addresses. */
407 if (ia != NULL) {
408 ip->ip_src = IA_SIN(ia)->sin_addr;
409 src_was_INADDR_ANY = 1;
410 }
411 }
412
413 if (ip->ip_src.s_addr != INADDR_ANY) {
414 struct in_multi *inm;
415
416 IN_LOOKUP_MULTI(pkt_dst, ifp, inm);
417 if (inm != NULL &&
418 (imo == NULL || imo->imo_multicast_loop)) {
419 /*
420 * If we belong to the destination multicast
421 * group on the outgoing interface, and the
422 * caller did not forbid loopback, loop back
423 * a copy.
424 */
425 ip_mloopback(ifp, m, dst, hlen);
426 } else {
427 /*
428 * If we are acting as a multicast router,
429 * perform multicast forwarding as if the
430 * packet had just arrived on the interface
431 * to which we are about to send. The
432 * multicast forwarding function recursively
433 * calls this function, using the IP_FORWARDING
434 * flag to prevent infinite recursion.
435 *
436 * Multicasts that are looped back by
437 * ip_mloopback(), above, will be forwarded by
438 * the ip_input() routine, if necessary.
439 */
440 if (ip_mrouter && !(flags & IP_FORWARDING)) {
441 /*
442 * If rsvp daemon is not running, do
443 * not set ip_moptions. This ensures
444 * that the packet is multicast and
445 * not just sent down one link as
446 * prescribed by rsvpd.
447 */
448 if (!rsvp_on)
449 imo = NULL;
450 if (ip_mforward) {
451 get_mplock();
452 if (ip_mforward(ip, ifp,
453 m, imo) != 0) {
454 m_freem(m);
455 rel_mplock();
456 goto done;
457 }
458 rel_mplock();
459 }
460 }
461 }
462 }
463
464 /*
465 * Multicasts with a time-to-live of zero may be looped-
466 * back, above, but must not be transmitted on a network.
467 * Also, multicasts addressed to the loopback interface
468 * are not sent -- the above call to ip_mloopback() will
469 * loop back a copy if this host actually belongs to the
470 * destination group on the loopback interface.
471 */
472 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
473 m_freem(m);
474 goto done;
475 }
476
477 goto sendit;
478 } else {
479 m->m_flags &= ~M_MCAST;
480 }
481
482 /*
483 * If the source address is not specified yet, use the address
484 * of the outgoing interface. In case, keep note we did that,
485 * so if the the firewall changes the next-hop causing the output
486 * interface to change, we can fix that.
487 */
488 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
489 /* Interface may have no addresses. */
490 if (ia != NULL) {
491 ip->ip_src = IA_SIN(ia)->sin_addr;
492 src_was_INADDR_ANY = 1;
493 }
494 }
495
496 /*
497 * Look for broadcast address and
498 * verify user is allowed to send
499 * such a packet.
500 */
501 if (isbroadcast) {
502 if (!(ifp->if_flags & IFF_BROADCAST)) {
503 error = EADDRNOTAVAIL;
504 goto bad;
505 }
506 if (!(flags & IP_ALLOWBROADCAST)) {
507 error = EACCES;
508 goto bad;
509 }
510 /* don't allow broadcast messages to be fragmented */
511 if (ip->ip_len > ifp->if_mtu) {
512 error = EMSGSIZE;
513 goto bad;
514 }
515 m->m_flags |= M_BCAST;
516 } else {
517 m->m_flags &= ~M_BCAST;
518 }
519
520 sendit:
521 #ifdef IPSEC
522 /* get SP for this packet */
523 if (so == NULL)
524 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error);
525 else
526 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
527
528 if (sp == NULL) {
529 ipsecstat.out_inval++;
530 goto bad;
531 }
532
533 error = 0;
534
535 /* check policy */
536 switch (sp->policy) {
537 case IPSEC_POLICY_DISCARD:
538 /*
539 * This packet is just discarded.
540 */
541 ipsecstat.out_polvio++;
542 goto bad;
543
544 case IPSEC_POLICY_BYPASS:
545 case IPSEC_POLICY_NONE:
546 case IPSEC_POLICY_TCP:
547 /* no need to do IPsec. */
548 goto skip_ipsec;
549
550 case IPSEC_POLICY_IPSEC:
551 if (sp->req == NULL) {
552 /* acquire a policy */
553 error = key_spdacquire(sp);
554 goto bad;
555 }
556 break;
557
558 case IPSEC_POLICY_ENTRUST:
559 default:
560 kprintf("ip_output: Invalid policy found. %d\n", sp->policy);
561 }
562 {
563 struct ipsec_output_state state;
564 bzero(&state, sizeof state);
565 state.m = m;
566 if (flags & IP_ROUTETOIF) {
567 state.ro = &iproute;
568 bzero(&iproute, sizeof iproute);
569 } else
570 state.ro = ro;
571 state.dst = (struct sockaddr *)dst;
572
573 ip->ip_sum = 0;
574
575 /*
576 * XXX
577 * delayed checksums are not currently compatible with IPsec
578 */
579 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
580 in_delayed_cksum(m);
581 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
582 }
583
584 ip->ip_len = htons(ip->ip_len);
585 ip->ip_off = htons(ip->ip_off);
586
587 error = ipsec4_output(&state, sp, flags);
588
589 m = state.m;
590 if (flags & IP_ROUTETOIF) {
591 /*
592 * if we have tunnel mode SA, we may need to ignore
593 * IP_ROUTETOIF.
594 */
595 if (state.ro != &iproute || state.ro->ro_rt != NULL) {
596 flags &= ~IP_ROUTETOIF;
597 ro = state.ro;
598 }
599 } else
600 ro = state.ro;
601 dst = (struct sockaddr_in *)state.dst;
602 if (error) {
603 /* mbuf is already reclaimed in ipsec4_output. */
604 m0 = NULL;
605 switch (error) {
606 case EHOSTUNREACH:
607 case ENETUNREACH:
608 case EMSGSIZE:
609 case ENOBUFS:
610 case ENOMEM:
611 break;
612 default:
613 kprintf("ip4_output (ipsec): error code %d\n", error);
614 /*fall through*/
615 case ENOENT:
616 /* don't show these error codes to the user */
617 error = 0;
618 break;
619 }
620 goto bad;
621 }
622 }
623
624 /* be sure to update variables that are affected by ipsec4_output() */
625 ip = mtod(m, struct ip *);
626 #ifdef _IP_VHL
627 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
628 #else
629 hlen = ip->ip_hl << 2;
630 #endif
631 if (ro->ro_rt == NULL) {
632 if (!(flags & IP_ROUTETOIF)) {
633 kprintf("ip_output: "
634 "can't update route after IPsec processing\n");
635 error = EHOSTUNREACH; /*XXX*/
636 goto bad;
637 }
638 } else {
639 ia = ifatoia(ro->ro_rt->rt_ifa);
640 ifp = ro->ro_rt->rt_ifp;
641 }
642
643 /* make it flipped, again. */
644 ip->ip_len = ntohs(ip->ip_len);
645 ip->ip_off = ntohs(ip->ip_off);
646 skip_ipsec:
647 #endif /*IPSEC*/
648 #ifdef FAST_IPSEC
649 /*
650 * Check the security policy (SP) for the packet and, if
651 * required, do IPsec-related processing. There are two
652 * cases here; the first time a packet is sent through
653 * it will be untagged and handled by ipsec4_checkpolicy.
654 * If the packet is resubmitted to ip_output (e.g. after
655 * AH, ESP, etc. processing), there will be a tag to bypass
656 * the lookup and related policy checking.
657 */
658 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
659 crit_enter();
660 if (mtag != NULL) {
661 tdbi = (struct tdb_ident *)m_tag_data(mtag);
662 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
663 if (sp == NULL)
664 error = -EINVAL; /* force silent drop */
665 m_tag_delete(m, mtag);
666 } else {
667 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags,
668 &error, inp);
669 }
670 /*
671 * There are four return cases:
672 * sp != NULL apply IPsec policy
673 * sp == NULL, error == 0 no IPsec handling needed
674 * sp == NULL, error == -EINVAL discard packet w/o error
675 * sp == NULL, error != 0 discard packet, report error
676 */
677 if (sp != NULL) {
678 /* Loop detection, check if ipsec processing already done */
679 KASSERT(sp->req != NULL, ("ip_output: no ipsec request"));
680 for (mtag = m_tag_first(m); mtag != NULL;
681 mtag = m_tag_next(m, mtag)) {
682 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
683 continue;
684 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
685 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
686 continue;
687 /*
688 * Check if policy has an SA associated with it.
689 * This can happen when an SP has yet to acquire
690 * an SA; e.g. on first reference. If it occurs,
691 * then we let ipsec4_process_packet do its thing.
692 */
693 if (sp->req->sav == NULL)
694 break;
695 tdbi = (struct tdb_ident *)m_tag_data(mtag);
696 if (tdbi->spi == sp->req->sav->spi &&
697 tdbi->proto == sp->req->sav->sah->saidx.proto &&
698 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst,
699 sizeof(union sockaddr_union)) == 0) {
700 /*
701 * No IPsec processing is needed, free
702 * reference to SP.
703 *
704 * NB: null pointer to avoid free at
705 * done: below.
706 */
707 KEY_FREESP(&sp), sp = NULL;
708 crit_exit();
709 goto spd_done;
710 }
711 }
712
713 /*
714 * Do delayed checksums now because we send before
715 * this is done in the normal processing path.
716 */
717 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
718 in_delayed_cksum(m);
719 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
720 }
721
722 ip->ip_len = htons(ip->ip_len);
723 ip->ip_off = htons(ip->ip_off);
724
725 /* NB: callee frees mbuf */
726 error = ipsec4_process_packet(m, sp->req, flags, 0);
727 /*
728 * Preserve KAME behaviour: ENOENT can be returned
729 * when an SA acquire is in progress. Don't propagate
730 * this to user-level; it confuses applications.
731 *
732 * XXX this will go away when the SADB is redone.
733 */
734 if (error == ENOENT)
735 error = 0;
736 crit_exit();
737 goto done;
738 } else {
739 crit_exit();
740
741 if (error != 0) {
742 /*
743 * Hack: -EINVAL is used to signal that a packet
744 * should be silently discarded. This is typically
745 * because we asked key management for an SA and
746 * it was delayed (e.g. kicked up to IKE).
747 */
748 if (error == -EINVAL)
749 error = 0;
750 goto bad;
751 } else {
752 /* No IPsec processing for this packet. */
753 }
754 #ifdef notyet
755 /*
756 * If deferred crypto processing is needed, check that
757 * the interface supports it.
758 */
759 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL);
760 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) {
761 /* notify IPsec to do its own crypto */
762 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag));
763 error = EHOSTUNREACH;
764 goto bad;
765 }
766 #endif
767 }
768 spd_done:
769 #endif /* FAST_IPSEC */
770
771 /* We are already being fwd'd from a firewall. */
772 if (next_hop != NULL)
773 goto pass;
774
775 /* No pfil hooks */
776 if (!pfil_has_hooks(&inet_pfil_hook)) {
777 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
778 /*
779 * Strip dummynet tags from stranded packets
780 */
781 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
782 KKASSERT(mtag != NULL);
783 m_tag_delete(m, mtag);
784 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED;
785 }
786 goto pass;
787 }
788
789 /*
790 * IpHack's section.
791 * - Xlate: translate packet's addr/port (NAT).
792 * - Firewall: deny/allow/etc.
793 * - Wrap: fake packet's addr/port <unimpl.>
794 * - Encapsulate: put it in another IP and send out. <unimp.>
795 */
796
797 /*
798 * Run through list of hooks for output packets.
799 */
800 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT);
801 if (error != 0 || m == NULL)
802 goto done;
803 ip = mtod(m, struct ip *);
804
805 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
806 /*
807 * Check dst to make sure it is directly reachable on the
808 * interface we previously thought it was.
809 * If it isn't (which may be likely in some situations) we have
810 * to re-route it (ie, find a route for the next-hop and the
811 * associated interface) and set them here. This is nested
812 * forwarding which in most cases is undesirable, except where
813 * such control is nigh impossible. So we do it here.
814 * And I'm babbling.
815 */
816 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
817 KKASSERT(mtag != NULL);
818 next_hop = m_tag_data(mtag);
819
820 /*
821 * Try local forwarding first
822 */
823 if (ip_localforward(m, next_hop, hlen))
824 goto done;
825
826 /*
827 * Relocate the route based on next_hop.
828 * If the current route is inp's cache, keep it untouched.
829 */
830 if (ro == &iproute && ro->ro_rt != NULL) {
831 RTFREE(ro->ro_rt);
832 ro->ro_rt = NULL;
833 }
834 ro = &iproute;
835 bzero(ro, sizeof *ro);
836
837 /*
838 * Forwarding to broadcast address is not allowed.
839 * XXX Should we follow IP_ROUTETOIF?
840 */
841 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF);
842
843 /* We are doing forwarding now */
844 flags |= IP_FORWARDING;
845
846 goto reroute;
847 }
848
849 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
850 struct dn_pkt *dn_pkt;
851
852 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
853 KKASSERT(mtag != NULL);
854 dn_pkt = m_tag_data(mtag);
855
856 /*
857 * Under certain cases it is not possible to recalculate
858 * 'ro' and 'dst', let alone 'flags', so just save them in
859 * dummynet tag and avoid the possible wrong reculcalation
860 * when we come back to ip_output() again.
861 *
862 * All other parameters have been already used and so they
863 * are not needed anymore.
864 * XXX if the ifp is deleted while a pkt is in dummynet,
865 * we are in trouble! (TODO use ifnet_detach_event)
866 *
867 * We need to copy *ro because for ICMP pkts (and maybe
868 * others) the caller passed a pointer into the stack;
869 * dst might also be a pointer into *ro so it needs to
870 * be updated.
871 */
872 dn_pkt->ro = *ro;
873 if (ro->ro_rt)
874 ro->ro_rt->rt_refcnt++;
875 if (dst == (struct sockaddr_in *)&ro->ro_dst) {
876 /* 'dst' points into 'ro' */
877 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst);
878 }
879 dn_pkt->dn_dst = dst;
880 dn_pkt->flags = flags;
881
882 ip_dn_queue(m);
883 goto done;
884 }
885 pass:
886 /* 127/8 must not appear on wire - RFC1122. */
887 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
888 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
889 if (!(ifp->if_flags & IFF_LOOPBACK)) {
890 ipstat.ips_badaddr++;
891 error = EADDRNOTAVAIL;
892 goto bad;
893 }
894 }
895 if (ip->ip_src.s_addr == INADDR_ANY ||
896 IN_MULTICAST(ntohl(ip->ip_src.s_addr))) {
897 ipstat.ips_badaddr++;
898 error = EADDRNOTAVAIL;
899 goto bad;
900 }
901
902 if ((m->m_pkthdr.csum_flags & CSUM_TSO) == 0) {
903 m->m_pkthdr.csum_flags |= CSUM_IP;
904 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
905 if (sw_csum & CSUM_DELAY_DATA) {
906 in_delayed_cksum(m);
907 sw_csum &= ~CSUM_DELAY_DATA;
908 }
909 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
910 } else {
911 sw_csum = 0;
912 }
913 m->m_pkthdr.csum_iphlen = hlen;
914
915 /*
916 * If small enough for interface, or the interface will take
917 * care of the fragmentation or segmentation for us, can just
918 * send directly.
919 */
920 if (ip->ip_len <= ifp->if_mtu ||
921 ((ifp->if_hwassist & CSUM_FRAGMENT) && !(ip->ip_off & IP_DF)) ||
922 (m->m_pkthdr.csum_flags & CSUM_TSO)) {
923 ip->ip_len = htons(ip->ip_len);
924 ip->ip_off = htons(ip->ip_off);
925 ip->ip_sum = 0;
926 if (sw_csum & CSUM_DELAY_IP) {
927 if (ip->ip_vhl == IP_VHL_BORING)
928 ip->ip_sum = in_cksum_hdr(ip);
929 else
930 ip->ip_sum = in_cksum(m, hlen);
931 }
932
933 /* Record statistics for this interface address. */
934 if (!(flags & IP_FORWARDING) && ia) {
935 IFA_STAT_INC(&ia->ia_ifa, opackets, 1);
936 IFA_STAT_INC(&ia->ia_ifa, obytes, m->m_pkthdr.len);
937 }
938
939 #ifdef IPSEC
940 /* clean ipsec history once it goes out of the node */
941 ipsec_delaux(m);
942 #endif
943
944 #ifdef MBUF_STRESS_TEST
945 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) {
946 struct mbuf *m1, *m2;
947 int length, tmp;
948
949 tmp = length = m->m_pkthdr.len;
950
951 while ((length -= mbuf_frag_size) >= 1) {
952 m1 = m_split(m, length, MB_DONTWAIT);
953 if (m1 == NULL)
954 break;
955 m2 = m;
956 while (m2->m_next != NULL)
957 m2 = m2->m_next;
958 m2->m_next = m1;
959 }
960 m->m_pkthdr.len = tmp;
961 }
962 #endif
963
964 #ifdef MPLS
965 if (!mpls_output_process(m, ro->ro_rt))
966 goto done;
967 #endif
968 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
969 ro->ro_rt);
970 goto done;
971 }
972
973 if (ip->ip_off & IP_DF) {
974 error = EMSGSIZE;
975 /*
976 * This case can happen if the user changed the MTU
977 * of an interface after enabling IP on it. Because
978 * most netifs don't keep track of routes pointing to
979 * them, there is no way for one to update all its
980 * routes when the MTU is changed.
981 */
982 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) &&
983 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) &&
984 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) {
985 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
986 }
987 ipstat.ips_cantfrag++;
988 goto bad;
989 }
990
991 /*
992 * Too large for interface; fragment if possible. If successful,
993 * on return, m will point to a list of packets to be sent.
994 */
995 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum);
996 if (error)
997 goto bad;
998 for (; m; m = m0) {
999 m0 = m->m_nextpkt;
1000 m->m_nextpkt = NULL;
1001 #ifdef IPSEC
1002 /* clean ipsec history once it goes out of the node */
1003 ipsec_delaux(m);
1004 #endif
1005 if (error == 0) {
1006 /* Record statistics for this interface address. */
1007 if (ia != NULL) {
1008 IFA_STAT_INC(&ia->ia_ifa, opackets, 1);
1009 IFA_STAT_INC(&ia->ia_ifa, obytes,
1010 m->m_pkthdr.len);
1011 }
1012 #ifdef MPLS
1013 if (!mpls_output_process(m, ro->ro_rt))
1014 continue;
1015 #endif
1016 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
1017 ro->ro_rt);
1018 } else {
1019 m_freem(m);
1020 }
1021 }
1022
1023 if (error == 0)
1024 ipstat.ips_fragmented++;
1025
1026 done:
1027 if (ro == &iproute && ro->ro_rt != NULL) {
1028 RTFREE(ro->ro_rt);
1029 ro->ro_rt = NULL;
1030 }
1031 #ifdef IPSEC
1032 if (sp != NULL) {
1033 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1034 kprintf("DP ip_output call free SP:%p\n", sp));
1035 key_freesp(sp);
1036 }
1037 #endif
1038 #ifdef FAST_IPSEC
1039 if (sp != NULL)
1040 KEY_FREESP(&sp);
1041 #endif
1042 return (error);
1043 bad:
1044 m_freem(m);
1045 goto done;
1046 }
1047
1048 /*
1049 * Create a chain of fragments which fit the given mtu. m_frag points to the
1050 * mbuf to be fragmented; on return it points to the chain with the fragments.
1051 * Return 0 if no error. If error, m_frag may contain a partially built
1052 * chain of fragments that should be freed by the caller.
1053 *
1054 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
1055 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
1056 */
1057 int
1058 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
1059 u_long if_hwassist_flags, int sw_csum)
1060 {
1061 int error = 0;
1062 int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
1063 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
1064 int off;
1065 struct mbuf *m0 = *m_frag; /* the original packet */
1066 int firstlen;
1067 struct mbuf **mnext;
1068 int nfrags;
1069
1070 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */
1071 ipstat.ips_cantfrag++;
1072 return EMSGSIZE;
1073 }
1074
1075 /*
1076 * Must be able to put at least 8 bytes per fragment.
1077 */
1078 if (len < 8)
1079 return EMSGSIZE;
1080
1081 /*
1082 * If the interface will not calculate checksums on
1083 * fragmented packets, then do it here.
1084 */
1085 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) &&
1086 !(if_hwassist_flags & CSUM_IP_FRAGS)) {
1087 in_delayed_cksum(m0);
1088 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1089 }
1090
1091 if (len > PAGE_SIZE) {
1092 /*
1093 * Fragment large datagrams such that each segment
1094 * contains a multiple of PAGE_SIZE amount of data,
1095 * plus headers. This enables a receiver to perform
1096 * page-flipping zero-copy optimizations.
1097 *
1098 * XXX When does this help given that sender and receiver
1099 * could have different page sizes, and also mtu could
1100 * be less than the receiver's page size ?
1101 */
1102 int newlen;
1103 struct mbuf *m;
1104
1105 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next)
1106 off += m->m_len;
1107
1108 /*
1109 * firstlen (off - hlen) must be aligned on an
1110 * 8-byte boundary
1111 */
1112 if (off < hlen)
1113 goto smart_frag_failure;
1114 off = ((off - hlen) & ~7) + hlen;
1115 newlen = (~PAGE_MASK) & mtu;
1116 if ((newlen + sizeof(struct ip)) > mtu) {
1117 /* we failed, go back the default */
1118 smart_frag_failure:
1119 newlen = len;
1120 off = hlen + len;
1121 }
1122 len = newlen;
1123
1124 } else {
1125 off = hlen + len;
1126 }
1127
1128 firstlen = off - hlen;
1129 mnext = &m0->m_nextpkt; /* pointer to next packet */
1130
1131 /*
1132 * Loop through length of segment after first fragment,
1133 * make new header and copy data of each part and link onto chain.
1134 * Here, m0 is the original packet, m is the fragment being created.
1135 * The fragments are linked off the m_nextpkt of the original
1136 * packet, which after processing serves as the first fragment.
1137 */
1138 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) {
1139 struct ip *mhip; /* ip header on the fragment */
1140 struct mbuf *m;
1141 int mhlen = sizeof(struct ip);
1142
1143 MGETHDR(m, MB_DONTWAIT, MT_HEADER);
1144 if (m == NULL) {
1145 error = ENOBUFS;
1146 ipstat.ips_odropped++;
1147 goto done;
1148 }
1149 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
1150 /*
1151 * In the first mbuf, leave room for the link header, then
1152 * copy the original IP header including options. The payload
1153 * goes into an additional mbuf chain returned by m_copy().
1154 */
1155 m->m_data += max_linkhdr;
1156 mhip = mtod(m, struct ip *);
1157 *mhip = *ip;
1158 if (hlen > sizeof(struct ip)) {
1159 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip);
1160 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2);
1161 }
1162 m->m_len = mhlen;
1163 /* XXX do we need to add ip->ip_off below ? */
1164 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
1165 if (off + len >= ip->ip_len) { /* last fragment */
1166 len = ip->ip_len - off;
1167 m->m_flags |= M_LASTFRAG;
1168 } else
1169 mhip->ip_off |= IP_MF;
1170 mhip->ip_len = htons((u_short)(len + mhlen));
1171 m->m_next = m_copy(m0, off, len);
1172 if (m->m_next == NULL) { /* copy failed */
1173 m_free(m);
1174 error = ENOBUFS; /* ??? */
1175 ipstat.ips_odropped++;
1176 goto done;
1177 }
1178 m->m_pkthdr.len = mhlen + len;
1179 m->m_pkthdr.rcvif = NULL;
1180 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
1181 m->m_pkthdr.csum_iphlen = mhlen;
1182 mhip->ip_off = htons(mhip->ip_off);
1183 mhip->ip_sum = 0;
1184 if (sw_csum & CSUM_DELAY_IP)
1185 mhip->ip_sum = in_cksum(m, mhlen);
1186 *mnext = m;
1187 mnext = &m->m_nextpkt;
1188 }
1189 ipstat.ips_ofragments += nfrags;
1190
1191 /* set first marker for fragment chain */
1192 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1193 m0->m_pkthdr.csum_data = nfrags;
1194
1195 /*
1196 * Update first fragment by trimming what's been copied out
1197 * and updating header.
1198 */
1199 m_adj(m0, hlen + firstlen - ip->ip_len);
1200 m0->m_pkthdr.len = hlen + firstlen;
1201 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1202 ip->ip_off |= IP_MF;
1203 ip->ip_off = htons(ip->ip_off);
1204 ip->ip_sum = 0;
1205 if (sw_csum & CSUM_DELAY_IP)
1206 ip->ip_sum = in_cksum(m0, hlen);
1207
1208 done:
1209 *m_frag = m0;
1210 return error;
1211 }
1212
1213 void
1214 in_delayed_cksum(struct mbuf *m)
1215 {
1216 struct ip *ip;
1217 u_short csum, offset;
1218
1219 ip = mtod(m, struct ip *);
1220 offset = IP_VHL_HL(ip->ip_vhl) << 2 ;
1221 csum = in_cksum_skip(m, ip->ip_len, offset);
1222 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
1223 csum = 0xffff;
1224 offset += m->m_pkthdr.csum_data; /* checksum offset */
1225
1226 if (offset + sizeof(u_short) > m->m_len) {
1227 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n",
1228 m->m_len, offset, ip->ip_p);
1229 /*
1230 * XXX
1231 * this shouldn't happen, but if it does, the
1232 * correct behavior may be to insert the checksum
1233 * in the existing chain instead of rearranging it.
1234 */
1235 m = m_pullup(m, offset + sizeof(u_short));
1236 }
1237 *(u_short *)(m->m_data + offset) = csum;
1238 }
1239
1240 /*
1241 * Insert IP options into preformed packet.
1242 * Adjust IP destination as required for IP source routing,
1243 * as indicated by a non-zero in_addr at the start of the options.
1244 *
1245 * XXX This routine assumes that the packet has no options in place.
1246 */
1247 static struct mbuf *
1248 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen)
1249 {
1250 struct ipoption *p = mtod(opt, struct ipoption *);
1251 struct mbuf *n;
1252 struct ip *ip = mtod(m, struct ip *);
1253 unsigned optlen;
1254
1255 optlen = opt->m_len - sizeof p->ipopt_dst;
1256 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) {
1257 *phlen = 0;
1258 return (m); /* XXX should fail */
1259 }
1260 if (p->ipopt_dst.s_addr)
1261 ip->ip_dst = p->ipopt_dst;
1262 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
1263 MGETHDR(n, MB_DONTWAIT, MT_HEADER);
1264 if (n == NULL) {
1265 *phlen = 0;
1266 return (m);
1267 }
1268 n->m_pkthdr.rcvif = NULL;
1269 n->m_pkthdr.len = m->m_pkthdr.len + optlen;
1270 m->m_len -= sizeof(struct ip);
1271 m->m_data += sizeof(struct ip);
1272 n->m_next = m;
1273 m = n;
1274 m->m_len = optlen + sizeof(struct ip);
1275 m->m_data += max_linkhdr;
1276 memcpy(mtod(m, void *), ip, sizeof(struct ip));
1277 } else {
1278 m->m_data -= optlen;
1279 m->m_len += optlen;
1280 m->m_pkthdr.len += optlen;
1281 ovbcopy(ip, mtod(m, caddr_t), sizeof(struct ip));
1282 }
1283 ip = mtod(m, struct ip *);
1284 bcopy(p->ipopt_list, ip + 1, optlen);
1285 *phlen = sizeof(struct ip) + optlen;
1286 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2);
1287 ip->ip_len += optlen;
1288 return (m);
1289 }
1290
1291 /*
1292 * Copy options from ip to jp,
1293 * omitting those not copied during fragmentation.
1294 */
1295 int
1296 ip_optcopy(struct ip *ip, struct ip *jp)
1297 {
1298 u_char *cp, *dp;
1299 int opt, optlen, cnt;
1300
1301 cp = (u_char *)(ip + 1);
1302 dp = (u_char *)(jp + 1);
1303 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
1304 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1305 opt = cp[0];
1306 if (opt == IPOPT_EOL)
1307 break;
1308 if (opt == IPOPT_NOP) {
1309 /* Preserve for IP mcast tunnel's LSRR alignment. */
1310 *dp++ = IPOPT_NOP;
1311 optlen = 1;
1312 continue;
1313 }
1314
1315 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp,
1316 ("ip_optcopy: malformed ipv4 option"));
1317 optlen = cp[IPOPT_OLEN];
1318 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt,
1319 ("ip_optcopy: malformed ipv4 option"));
1320
1321 /* bogus lengths should have been caught by ip_dooptions */
1322 if (optlen > cnt)
1323 optlen = cnt;
1324 if (IPOPT_COPIED(opt)) {
1325 bcopy(cp, dp, optlen);
1326 dp += optlen;
1327 }
1328 }
1329 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
1330 *dp++ = IPOPT_EOL;
1331 return (optlen);
1332 }
1333
1334 /*
1335 * IP socket option processing.
1336 */
1337 void
1338 ip_ctloutput(netmsg_t msg)
1339 {
1340 struct socket *so = msg->base.nm_so;
1341 struct sockopt *sopt = msg->ctloutput.nm_sopt;
1342 struct inpcb *inp = so->so_pcb;
1343 int error, optval;
1344
1345 error = optval = 0;
1346 if (sopt->sopt_level != IPPROTO_IP) {
1347 error = EINVAL;
1348 goto done;
1349 }
1350
1351 switch (sopt->sopt_dir) {
1352 case SOPT_SET:
1353 switch (sopt->sopt_name) {
1354 case IP_OPTIONS:
1355 #ifdef notyet
1356 case IP_RETOPTS:
1357 #endif
1358 {
1359 struct mbuf *m;
1360 if (sopt->sopt_valsize > MLEN) {
1361 error = EMSGSIZE;
1362 break;
1363 }
1364 MGET(m, sopt->sopt_td ? MB_WAIT : MB_DONTWAIT, MT_HEADER);
1365 if (m == NULL) {
1366 error = ENOBUFS;
1367 break;
1368 }
1369 m->m_len = sopt->sopt_valsize;
1370 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len,
1371 m->m_len);
1372 error = ip_pcbopts(sopt->sopt_name,
1373 &inp->inp_options, m);
1374 goto done;
1375 }
1376
1377 case IP_TOS:
1378 case IP_TTL:
1379 case IP_MINTTL:
1380 case IP_RECVOPTS:
1381 case IP_RECVRETOPTS:
1382 case IP_RECVDSTADDR:
1383 case IP_RECVIF:
1384 case IP_RECVTTL:
1385 case IP_FAITH:
1386 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1387 sizeof optval);
1388 if (error)
1389 break;
1390 switch (sopt->sopt_name) {
1391 case IP_TOS:
1392 inp->inp_ip_tos = optval;
1393 break;
1394
1395 case IP_TTL:
1396 inp->inp_ip_ttl = optval;
1397 break;
1398 case IP_MINTTL:
1399 if (optval >= 0 && optval <= MAXTTL)
1400 inp->inp_ip_minttl = optval;
1401 else
1402 error = EINVAL;
1403 break;
1404 #define OPTSET(bit) \
1405 if (optval) \
1406 inp->inp_flags |= bit; \
1407 else \
1408 inp->inp_flags &= ~bit;
1409
1410 case IP_RECVOPTS:
1411 OPTSET(INP_RECVOPTS);
1412 break;
1413
1414 case IP_RECVRETOPTS:
1415 OPTSET(INP_RECVRETOPTS);
1416 break;
1417
1418 case IP_RECVDSTADDR:
1419 OPTSET(INP_RECVDSTADDR);
1420 break;
1421
1422 case IP_RECVIF:
1423 OPTSET(INP_RECVIF);
1424 break;
1425
1426 case IP_RECVTTL:
1427 OPTSET(INP_RECVTTL);
1428 break;
1429
1430 case IP_FAITH:
1431 OPTSET(INP_FAITH);
1432 break;
1433 }
1434 break;
1435 #undef OPTSET
1436
1437 case IP_MULTICAST_IF:
1438 case IP_MULTICAST_VIF:
1439 case IP_MULTICAST_TTL:
1440 case IP_MULTICAST_LOOP:
1441 case IP_ADD_MEMBERSHIP:
1442 case IP_DROP_MEMBERSHIP:
1443 error = ip_setmoptions(sopt, &inp->inp_moptions);
1444 break;
1445
1446 case IP_PORTRANGE:
1447 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1448 sizeof optval);
1449 if (error)
1450 break;
1451
1452 switch (optval) {
1453 case IP_PORTRANGE_DEFAULT:
1454 inp->inp_flags &= ~(INP_LOWPORT);
1455 inp->inp_flags &= ~(INP_HIGHPORT);
1456 break;
1457
1458 case IP_PORTRANGE_HIGH:
1459 inp->inp_flags &= ~(INP_LOWPORT);
1460 inp->inp_flags |= INP_HIGHPORT;
1461 break;
1462
1463 case IP_PORTRANGE_LOW:
1464 inp->inp_flags &= ~(INP_HIGHPORT);
1465 inp->inp_flags |= INP_LOWPORT;
1466 break;
1467
1468 default:
1469 error = EINVAL;
1470 break;
1471 }
1472 break;
1473
1474 #if defined(IPSEC) || defined(FAST_IPSEC)
1475 case IP_IPSEC_POLICY:
1476 {
1477 caddr_t req;
1478 size_t len = 0;
1479 int priv;
1480 struct mbuf *m;
1481 int optname;
1482
1483 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1484 break;
1485 soopt_to_mbuf(sopt, m);
1486 priv = (sopt->sopt_td != NULL &&
1487 priv_check(sopt->sopt_td, PRIV_ROOT) != 0) ? 0 : 1;
1488 req = mtod(m, caddr_t);
1489 len = m->m_len;
1490 optname = sopt->sopt_name;
1491 error = ipsec4_set_policy(inp, optname, req, len, priv);
1492 m_freem(m);
1493 break;
1494 }
1495 #endif /*IPSEC*/
1496
1497 default:
1498 error = ENOPROTOOPT;
1499 break;
1500 }
1501 break;
1502
1503 case SOPT_GET:
1504 switch (sopt->sopt_name) {
1505 case IP_OPTIONS:
1506 case IP_RETOPTS:
1507 if (inp->inp_options)
1508 soopt_from_kbuf(sopt, mtod(inp->inp_options,
1509 char *),
1510 inp->inp_options->m_len);
1511 else
1512 sopt->sopt_valsize = 0;
1513 break;
1514
1515 case IP_TOS:
1516 case IP_TTL:
1517 case IP_MINTTL:
1518 case IP_RECVOPTS:
1519 case IP_RECVRETOPTS:
1520 case IP_RECVDSTADDR:
1521 case IP_RECVTTL:
1522 case IP_RECVIF:
1523 case IP_PORTRANGE:
1524 case IP_FAITH:
1525 switch (sopt->sopt_name) {
1526
1527 case IP_TOS:
1528 optval = inp->inp_ip_tos;
1529 break;
1530
1531 case IP_TTL:
1532 optval = inp->inp_ip_ttl;
1533 break;
1534 case IP_MINTTL:
1535 optval = inp->inp_ip_minttl;
1536 break;
1537
1538 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1539
1540 case IP_RECVOPTS:
1541 optval = OPTBIT(INP_RECVOPTS);
1542 break;
1543
1544 case IP_RECVRETOPTS:
1545 optval = OPTBIT(INP_RECVRETOPTS);
1546 break;
1547
1548 case IP_RECVDSTADDR:
1549 optval = OPTBIT(INP_RECVDSTADDR);
1550 break;
1551
1552 case IP_RECVTTL:
1553 optval = OPTBIT(INP_RECVTTL);
1554 break;
1555
1556 case IP_RECVIF:
1557 optval = OPTBIT(INP_RECVIF);
1558 break;
1559
1560 case IP_PORTRANGE:
1561 if (inp->inp_flags & INP_HIGHPORT)
1562 optval = IP_PORTRANGE_HIGH;
1563 else if (inp->inp_flags & INP_LOWPORT)
1564 optval = IP_PORTRANGE_LOW;
1565 else
1566 optval = 0;
1567 break;
1568
1569 case IP_FAITH:
1570 optval = OPTBIT(INP_FAITH);
1571 break;
1572 }
1573 soopt_from_kbuf(sopt, &optval, sizeof optval);
1574 break;
1575
1576 case IP_MULTICAST_IF:
1577 case IP_MULTICAST_VIF:
1578 case IP_MULTICAST_TTL:
1579 case IP_MULTICAST_LOOP:
1580 case IP_ADD_MEMBERSHIP:
1581 case IP_DROP_MEMBERSHIP:
1582 error = ip_getmoptions(sopt, inp->inp_moptions);
1583 break;
1584
1585 #if defined(IPSEC) || defined(FAST_IPSEC)
1586 case IP_IPSEC_POLICY:
1587 {
1588 struct mbuf *m = NULL;
1589 caddr_t req = NULL;
1590 size_t len = 0;
1591
1592 if (m != NULL) {
1593 req = mtod(m, caddr_t);
1594 len = m->m_len;
1595 }
1596 error = ipsec4_get_policy(so->so_pcb, req, len, &m);
1597 if (error == 0)
1598 error = soopt_from_mbuf(sopt, m); /* XXX */
1599 if (error == 0)
1600 m_freem(m);
1601 break;
1602 }
1603 #endif /*IPSEC*/
1604
1605 default:
1606 error = ENOPROTOOPT;
1607 break;
1608 }
1609 break;
1610 }
1611 done:
1612 lwkt_replymsg(&msg->lmsg, error);
1613 }
1614
1615 /*
1616 * Set up IP options in pcb for insertion in output packets.
1617 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1618 * with destination address if source routed.
1619 */
1620 static int
1621 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m)
1622 {
1623 int cnt, optlen;
1624 u_char *cp;
1625 u_char opt;
1626
1627 /* turn off any old options */
1628 if (*pcbopt)
1629 m_free(*pcbopt);
1630 *pcbopt = NULL;
1631 if (m == NULL || m->m_len == 0) {
1632 /*
1633 * Only turning off any previous options.
1634 */
1635 if (m != NULL)
1636 m_free(m);
1637 return (0);
1638 }
1639
1640 if (m->m_len % sizeof(int32_t))
1641 goto bad;
1642 /*
1643 * IP first-hop destination address will be stored before
1644 * actual options; move other options back
1645 * and clear it when none present.
1646 */
1647 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
1648 goto bad;
1649 cnt = m->m_len;
1650 m->m_len += sizeof(struct in_addr);
1651 cp = mtod(m, u_char *) + sizeof(struct in_addr);
1652 ovbcopy(mtod(m, caddr_t), cp, cnt);
1653 bzero(mtod(m, caddr_t), sizeof(struct in_addr));
1654
1655 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1656 opt = cp[IPOPT_OPTVAL];
1657 if (opt == IPOPT_EOL)
1658 break;
1659 if (opt == IPOPT_NOP)
1660 optlen = 1;
1661 else {
1662 if (cnt < IPOPT_OLEN + sizeof *cp)
1663 goto bad;
1664 optlen = cp[IPOPT_OLEN];
1665 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt)
1666 goto bad;
1667 }
1668 switch (opt) {
1669
1670 default:
1671 break;
1672
1673 case IPOPT_LSRR:
1674 case IPOPT_SSRR:
1675 /*
1676 * user process specifies route as:
1677 * ->A->B->C->D
1678 * D must be our final destination (but we can't
1679 * check that since we may not have connected yet).
1680 * A is first hop destination, which doesn't appear in
1681 * actual IP option, but is stored before the options.
1682 */
1683 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
1684 goto bad;
1685 m->m_len -= sizeof(struct in_addr);
1686 cnt -= sizeof(struct in_addr);
1687 optlen -= sizeof(struct in_addr);
1688 cp[IPOPT_OLEN] = optlen;
1689 /*
1690 * Move first hop before start of options.
1691 */
1692 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
1693 sizeof(struct in_addr));
1694 /*
1695 * Then copy rest of options back
1696 * to close up the deleted entry.
1697 */
1698 ovbcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr),
1699 &cp[IPOPT_OFFSET+1],
1700 cnt - (IPOPT_MINOFF - 1));
1701 break;
1702 }
1703 }
1704 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
1705 goto bad;
1706 *pcbopt = m;
1707 return (0);
1708
1709 bad:
1710 m_free(m);
1711 return (EINVAL);
1712 }
1713
1714 /*
1715 * XXX
1716 * The whole multicast option thing needs to be re-thought.
1717 * Several of these options are equally applicable to non-multicast
1718 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1719 * standard option (IP_TTL).
1720 */
1721
1722 /*
1723 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1724 */
1725 static struct ifnet *
1726 ip_multicast_if(struct in_addr *a, int *ifindexp)
1727 {
1728 int ifindex;
1729 struct ifnet *ifp;
1730
1731 if (ifindexp)
1732 *ifindexp = 0;
1733 if (ntohl(a->s_addr) >> 24 == 0) {
1734 ifindex = ntohl(a->s_addr) & 0xffffff;
1735 if (ifindex < 0 || if_index < ifindex)
1736 return NULL;
1737 ifp = ifindex2ifnet[ifindex];
1738 if (ifindexp)
1739 *ifindexp = ifindex;
1740 } else {
1741 ifp = INADDR_TO_IFP(a);
1742 }
1743 return ifp;
1744 }
1745
1746 /*
1747 * Set the IP multicast options in response to user setsockopt().
1748 */
1749 static int
1750 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop)
1751 {
1752 int error = 0;
1753 int i;
1754 struct in_addr addr;
1755 struct ip_mreq mreq;
1756 struct ifnet *ifp;
1757 struct ip_moptions *imo = *imop;
1758 int ifindex;
1759
1760 if (imo == NULL) {
1761 /*
1762 * No multicast option buffer attached to the pcb;
1763 * allocate one and initialize to default values.
1764 */
1765 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK);
1766
1767 *imop = imo;
1768 imo->imo_multicast_ifp = NULL;
1769 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1770 imo->imo_multicast_vif = -1;
1771 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1772 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
1773 imo->imo_num_memberships = 0;
1774 }
1775 switch (sopt->sopt_name) {
1776 /* store an index number for the vif you wanna use in the send */
1777 case IP_MULTICAST_VIF:
1778 if (legal_vif_num == 0) {
1779 error = EOPNOTSUPP;
1780 break;
1781 }
1782 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i);
1783 if (error)
1784 break;
1785 if (!legal_vif_num(i) && (i != -1)) {
1786 error = EINVAL;
1787 break;
1788 }
1789 imo->imo_multicast_vif = i;
1790 break;
1791
1792 case IP_MULTICAST_IF:
1793 /*
1794 * Select the interface for outgoing multicast packets.
1795 */
1796 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr);
1797 if (error)
1798 break;
1799
1800 /*
1801 * INADDR_ANY is used to remove a previous selection.
1802 * When no interface is selected, a default one is
1803 * chosen every time a multicast packet is sent.
1804 */
1805 if (addr.s_addr == INADDR_ANY) {
1806 imo->imo_multicast_ifp = NULL;
1807 break;
1808 }
1809 /*
1810 * The selected interface is identified by its local
1811 * IP address. Find the interface and confirm that
1812 * it supports multicasting.
1813 */
1814 crit_enter();
1815 ifp = ip_multicast_if(&addr, &ifindex);
1816 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1817 crit_exit();
1818 error = EADDRNOTAVAIL;
1819 break;
1820 }
1821 imo->imo_multicast_ifp = ifp;
1822 if (ifindex)
1823 imo->imo_multicast_addr = addr;
1824 else
1825 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1826 crit_exit();
1827 break;
1828
1829 case IP_MULTICAST_TTL:
1830 /*
1831 * Set the IP time-to-live for outgoing multicast packets.
1832 * The original multicast API required a char argument,
1833 * which is inconsistent with the rest of the socket API.
1834 * We allow either a char or an int.
1835 */
1836 if (sopt->sopt_valsize == 1) {
1837 u_char ttl;
1838 error = soopt_to_kbuf(sopt, &ttl, 1, 1);
1839 if (error)
1840 break;
1841 imo->imo_multicast_ttl = ttl;
1842 } else {
1843 u_int ttl;
1844 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl);
1845 if (error)
1846 break;
1847 if (ttl > 255)
1848 error = EINVAL;
1849 else
1850 imo->imo_multicast_ttl = ttl;
1851 }
1852 break;
1853
1854 case IP_MULTICAST_LOOP:
1855 /*
1856 * Set the loopback flag for outgoing multicast packets.
1857 * Must be zero or one. The original multicast API required a
1858 * char argument, which is inconsistent with the rest
1859 * of the socket API. We allow either a char or an int.
1860 */
1861 if (sopt->sopt_valsize == 1) {
1862 u_char loop;
1863
1864 error = soopt_to_kbuf(sopt, &loop, 1, 1);
1865 if (error)
1866 break;
1867 imo->imo_multicast_loop = !!loop;
1868 } else {
1869 u_int loop;
1870
1871 error = soopt_to_kbuf(sopt, &loop, sizeof loop,
1872 sizeof loop);
1873 if (error)
1874 break;
1875 imo->imo_multicast_loop = !!loop;
1876 }
1877 break;
1878
1879 case IP_ADD_MEMBERSHIP:
1880 /*
1881 * Add a multicast group membership.
1882 * Group must be a valid IP multicast address.
1883 */
1884 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1885 if (error)
1886 break;
1887
1888 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1889 error = EINVAL;
1890 break;
1891 }
1892 crit_enter();
1893 /*
1894 * If no interface address was provided, use the interface of
1895 * the route to the given multicast address.
1896 */
1897 if (mreq.imr_interface.s_addr == INADDR_ANY) {
1898 struct sockaddr_in dst;
1899 struct rtentry *rt;
1900
1901 bzero(&dst, sizeof(struct sockaddr_in));
1902 dst.sin_len = sizeof(struct sockaddr_in);
1903 dst.sin_family = AF_INET;
1904 dst.sin_addr = mreq.imr_multiaddr;
1905 rt = rtlookup((struct sockaddr *)&dst);
1906 if (rt == NULL) {
1907 error = EADDRNOTAVAIL;
1908 crit_exit();
1909 break;
1910 }
1911 --rt->rt_refcnt;
1912 ifp = rt->rt_ifp;
1913 } else {
1914 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1915 }
1916
1917 /*
1918 * See if we found an interface, and confirm that it
1919 * supports multicast.
1920 */
1921 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1922 error = EADDRNOTAVAIL;
1923 crit_exit();
1924 break;
1925 }
1926 /*
1927 * See if the membership already exists or if all the
1928 * membership slots are full.
1929 */
1930 for (i = 0; i < imo->imo_num_memberships; ++i) {
1931 if (imo->imo_membership[i]->inm_ifp == ifp &&
1932 imo->imo_membership[i]->inm_addr.s_addr
1933 == mreq.imr_multiaddr.s_addr)
1934 break;
1935 }
1936 if (i < imo->imo_num_memberships) {
1937 error = EADDRINUSE;
1938 crit_exit();
1939 break;
1940 }
1941 if (i == IP_MAX_MEMBERSHIPS) {
1942 error = ETOOMANYREFS;
1943 crit_exit();
1944 break;
1945 }
1946 /*
1947 * Everything looks good; add a new record to the multicast
1948 * address list for the given interface.
1949 */
1950 if ((imo->imo_membership[i] =
1951 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) {
1952 error = ENOBUFS;
1953 crit_exit();
1954 break;
1955 }
1956 ++imo->imo_num_memberships;
1957 crit_exit();
1958 break;
1959
1960 case IP_DROP_MEMBERSHIP:
1961 /*
1962 * Drop a multicast group membership.
1963 * Group must be a valid IP multicast address.
1964 */
1965 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1966 if (error)
1967 break;
1968
1969 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1970 error = EINVAL;
1971 break;
1972 }
1973
1974 crit_enter();
1975 /*
1976 * If an interface address was specified, get a pointer
1977 * to its ifnet structure.
1978 */
1979 if (mreq.imr_interface.s_addr == INADDR_ANY)
1980 ifp = NULL;
1981 else {
1982 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1983 if (ifp == NULL) {
1984 error = EADDRNOTAVAIL;
1985 crit_exit();
1986 break;
1987 }
1988 }
1989 /*
1990 * Find the membership in the membership array.
1991 */
1992 for (i = 0; i < imo->imo_num_memberships; ++i) {
1993 if ((ifp == NULL ||
1994 imo->imo_membership[i]->inm_ifp == ifp) &&
1995 imo->imo_membership[i]->inm_addr.s_addr ==
1996 mreq.imr_multiaddr.s_addr)
1997 break;
1998 }
1999 if (i == imo->imo_num_memberships) {
2000 error = EADDRNOTAVAIL;
2001 crit_exit();
2002 break;
2003 }
2004 /*
2005 * Give up the multicast address record to which the
2006 * membership points.
2007 */
2008 in_delmulti(imo->imo_membership[i]);
2009 /*
2010 * Remove the gap in the membership array.
2011 */
2012 for (++i; i < imo->imo_num_memberships; ++i)
2013 imo->imo_membership[i-1] = imo->imo_membership[i];
2014 --imo->imo_num_memberships;
2015 crit_exit();
2016 break;
2017
2018 default:
2019 error = EOPNOTSUPP;
2020 break;
2021 }
2022
2023 /*
2024 * If all options have default values, no need to keep the mbuf.
2025 */
2026 if (imo->imo_multicast_ifp == NULL &&
2027 imo->imo_multicast_vif == -1 &&
2028 imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
2029 imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
2030 imo->imo_num_memberships == 0) {
2031 kfree(*imop, M_IPMOPTS);
2032 *imop = NULL;
2033 }
2034
2035 return (error);
2036 }
2037
2038 /*
2039 * Return the IP multicast options in response to user getsockopt().
2040 */
2041 static int
2042 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo)
2043 {
2044 struct in_addr addr;
2045 struct in_ifaddr *ia;
2046 int error, optval;
2047 u_char coptval;
2048
2049 error = 0;
2050 switch (sopt->sopt_name) {
2051 case IP_MULTICAST_VIF:
2052 if (imo != NULL)
2053 optval = imo->imo_multicast_vif;
2054 else
2055 optval = -1;
2056 soopt_from_kbuf(sopt, &optval, sizeof optval);
2057 break;
2058
2059 case IP_MULTICAST_IF:
2060 if (imo == NULL || imo->imo_multicast_ifp == NULL)
2061 addr.s_addr = INADDR_ANY;
2062 else if (imo->imo_multicast_addr.s_addr) {
2063 /* return the value user has set */
2064 addr = imo->imo_multicast_addr;
2065 } else {
2066 ia = IFP_TO_IA(imo->imo_multicast_ifp);
2067 addr.s_addr = (ia == NULL) ? INADDR_ANY
2068 : IA_SIN(ia)->sin_addr.s_addr;
2069 }
2070 soopt_from_kbuf(sopt, &addr, sizeof addr);
2071 break;
2072
2073 case IP_MULTICAST_TTL:
2074 if (imo == NULL)
2075 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
2076 else
2077 optval = coptval = imo->imo_multicast_ttl;
2078 if (sopt->sopt_valsize == 1)
2079 soopt_from_kbuf(sopt, &coptval, 1);
2080 else
2081 soopt_from_kbuf(sopt, &optval, sizeof optval);
2082 break;
2083
2084 case IP_MULTICAST_LOOP:
2085 if (imo == NULL)
2086 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
2087 else
2088 optval = coptval = imo->imo_multicast_loop;
2089 if (sopt->sopt_valsize == 1)
2090 soopt_from_kbuf(sopt, &coptval, 1);
2091 else
2092 soopt_from_kbuf(sopt, &optval, sizeof optval);
2093 break;
2094
2095 default:
2096 error = ENOPROTOOPT;
2097 break;
2098 }
2099 return (error);
2100 }
2101
2102 /*
2103 * Discard the IP multicast options.
2104 */
2105 void
2106 ip_freemoptions(struct ip_moptions *imo)
2107 {
2108 int i;
2109
2110 if (imo != NULL) {
2111 for (i = 0; i < imo->imo_num_memberships; ++i)
2112 in_delmulti(imo->imo_membership[i]);
2113 kfree(imo, M_IPMOPTS);
2114 }
2115 }
2116
2117 /*
2118 * Routine called from ip_output() to loop back a copy of an IP multicast
2119 * packet to the input queue of a specified interface. Note that this
2120 * calls the output routine of the loopback "driver", but with an interface
2121 * pointer that might NOT be a loopback interface -- evil, but easier than
2122 * replicating that code here.
2123 */
2124 static void
2125 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst,
2126 int hlen)
2127 {
2128 struct ip *ip;
2129 struct mbuf *copym;
2130
2131 copym = m_copypacket(m, MB_DONTWAIT);
2132 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
2133 copym = m_pullup(copym, hlen);
2134 if (copym != NULL) {
2135 /*
2136 * if the checksum hasn't been computed, mark it as valid
2137 */
2138 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2139 in_delayed_cksum(copym);
2140 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
2141 copym->m_pkthdr.csum_flags |=
2142 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2143 copym->m_pkthdr.csum_data = 0xffff;
2144 }
2145 /*
2146 * We don't bother to fragment if the IP length is greater
2147 * than the interface's MTU. Can this possibly matter?
2148 */
2149 ip = mtod(copym, struct ip *);
2150 ip->ip_len = htons(ip->ip_len);
2151 ip->ip_off = htons(ip->ip_off);
2152 ip->ip_sum = 0;
2153 if (ip->ip_vhl == IP_VHL_BORING) {
2154 ip->ip_sum = in_cksum_hdr(ip);
2155 } else {
2156 ip->ip_sum = in_cksum(copym, hlen);
2157 }
2158 /*
2159 * NB:
2160 * It's not clear whether there are any lingering
2161 * reentrancy problems in other areas which might
2162 * be exposed by using ip_input directly (in
2163 * particular, everything which modifies the packet
2164 * in-place). Yet another option is using the
2165 * protosw directly to deliver the looped back
2166 * packet. For the moment, we'll err on the side
2167 * of safety by using if_simloop().
2168 */
2169 #if 1 /* XXX */
2170 if (dst->sin_family != AF_INET) {
2171 kprintf("ip_mloopback: bad address family %d\n",
2172 dst->sin_family);
2173 dst->sin_family = AF_INET;
2174 }
2175 #endif
2176 get_mplock(); /* is if_simloop() mpsafe yet? */
2177 if_simloop(ifp, copym, dst->sin_family, 0);
2178 rel_mplock();
2179 }
2180 }
Cache object: eda4dc40ce3ec8366949831ddaf9c19a
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