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kernel/extp{read,write}v: Change ioccnt from u_int to int.
[dragonfly.git] / sys / netinet / ip_output.c
blobc97538d52e284281bf49f9d2524759600258ab1e
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 int ip_do_rfc6864 = 1;
109 SYSCTL_INT(_net_inet_ip, OID_AUTO, rfc6864, CTLFLAG_RW, &ip_do_rfc6864, 0,
110 "Don't generate IP ID for DF IP datagrams");
111
112 static struct mbuf *ip_insertoptions(struct mbuf *, struct mbuf *, int *);
113 static struct ifnet *ip_multicast_if(struct in_addr *, int *);
114 static void ip_mloopback
115 (struct ifnet *, struct mbuf *, struct sockaddr_in *, int);
116 static int ip_getmoptions
117 (struct sockopt *, struct ip_moptions *);
118 static int ip_pcbopts(int, struct mbuf **, struct mbuf *);
119 static int ip_setmoptions
120 (struct sockopt *, struct ip_moptions **);
121
122 int ip_optcopy(struct ip *, struct ip *);
123
124 extern struct protosw inetsw[];
125
126 static int
127 ip_localforward(struct mbuf *m, const struct sockaddr_in *dst, int hlen)
128 {
129 struct in_ifaddr_container *iac;
130
131 /*
132 * We need to figure out if we have been forwarded to a local
133 * socket. If so, then we should somehow "loop back" to
134 * ip_input(), and get directed to the PCB as if we had received
135 * this packet. This is because it may be difficult to identify
136 * the packets you want to forward until they are being output
137 * and have selected an interface (e.g. locally initiated
138 * packets). If we used the loopback inteface, we would not be
139 * able to control what happens as the packet runs through
140 * ip_input() as it is done through a ISR.
141 */
142 LIST_FOREACH(iac, INADDR_HASH(dst->sin_addr.s_addr), ia_hash) {
143 /*
144 * If the addr to forward to is one of ours, we pretend
145 * to be the destination for this packet.
146 */
147 if (IA_SIN(iac->ia)->sin_addr.s_addr == dst->sin_addr.s_addr)
148 break;
149 }
150 if (iac != NULL) {
151 struct ip *ip;
152
153 if (m->m_pkthdr.rcvif == NULL)
154 m->m_pkthdr.rcvif = loif;
155 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
156 m->m_pkthdr.csum_flags |= CSUM_DATA_VALID |
157 CSUM_PSEUDO_HDR;
158 m->m_pkthdr.csum_data = 0xffff;
159 }
160 m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID;
161
162 /*
163 * Make sure that the IP header is in one mbuf,
164 * required by ip_input
165 */
166 if (m->m_len < hlen) {
167 m = m_pullup(m, hlen);
168 if (m == NULL) {
169 /* The packet was freed; we are done */
170 return 1;
171 }
172 }
173 ip = mtod(m, struct ip *);
174
175 ip->ip_len = htons(ip->ip_len);
176 ip->ip_off = htons(ip->ip_off);
177 ip_input(m);
178
179 return 1; /* The packet gets forwarded locally */
180 }
181 return 0;
182 }
183
184 /*
185 * IP output. The packet in mbuf chain m contains a skeletal IP
186 * header (with len, off, ttl, proto, tos, src, dst).
187 * The mbuf chain containing the packet will be freed.
188 * The mbuf opt, if present, will not be freed.
189 */
190 int
191 ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro,
192 int flags, struct ip_moptions *imo, struct inpcb *inp)
193 {
194 struct ip *ip;
195 struct ifnet *ifp = NULL; /* keep compiler happy */
196 struct mbuf *m;
197 int hlen = sizeof(struct ip);
198 int len, error = 0;
199 struct sockaddr_in *dst = NULL; /* keep compiler happy */
200 struct in_ifaddr *ia = NULL;
201 int isbroadcast, sw_csum;
202 struct in_addr pkt_dst;
203 struct route iproute;
204 struct m_tag *mtag;
205 #ifdef IPSEC
206 struct secpolicy *sp = NULL;
207 struct socket *so = inp ? inp->inp_socket : NULL;
208 #endif
209 #ifdef FAST_IPSEC
210 struct secpolicy *sp = NULL;
211 struct tdb_ident *tdbi;
212 #endif /* FAST_IPSEC */
213 struct sockaddr_in *next_hop = NULL;
214 int src_was_INADDR_ANY = 0; /* as the name says... */
215
216 ASSERT_NETISR_NCPUS(mycpuid);
217
218 m = m0;
219 M_ASSERTPKTHDR(m);
220
221 if (ro == NULL) {
222 ro = &iproute;
223 bzero(ro, sizeof *ro);
224 } else if (ro->ro_rt != NULL && ro->ro_rt->rt_cpuid != mycpuid) {
225 if (flags & IP_DEBUGROUTE) {
226 panic("ip_output: rt rt_cpuid %d accessed on cpu %d\n",
227 ro->ro_rt->rt_cpuid, mycpuid);
228 }
229
230 /*
231 * XXX
232 * If the cached rtentry's owner CPU is not the current CPU,
233 * then don't touch the cached rtentry (remote free is too
234 * expensive in this context); just relocate the route.
235 */
236 ro = &iproute;
237 bzero(ro, sizeof *ro);
238 }
239
240 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
241 /* Next hop */
242 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
243 KKASSERT(mtag != NULL);
244 next_hop = m_tag_data(mtag);
245 }
246
247 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
248 struct dn_pkt *dn_pkt;
249
250 /* Extract info from dummynet tag */
251 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
252 KKASSERT(mtag != NULL);
253 dn_pkt = m_tag_data(mtag);
254
255 /*
256 * The packet was already tagged, so part of the
257 * processing was already done, and we need to go down.
258 * Get the calculated parameters from the tag.
259 */
260 ifp = dn_pkt->ifp;
261
262 KKASSERT(ro == &iproute);
263 *ro = dn_pkt->ro; /* structure copy */
264 KKASSERT(ro->ro_rt == NULL || ro->ro_rt->rt_cpuid == mycpuid);
265
266 dst = dn_pkt->dn_dst;
267 if (dst == (struct sockaddr_in *)&(dn_pkt->ro.ro_dst)) {
268 /* If 'dst' points into dummynet tag, adjust it */
269 dst = (struct sockaddr_in *)&(ro->ro_dst);
270 }
271
272 ip = mtod(m, struct ip *);
273 hlen = IP_VHL_HL(ip->ip_vhl) << 2 ;
274 if (ro->ro_rt)
275 ia = ifatoia(ro->ro_rt->rt_ifa);
276 goto sendit;
277 }
278
279 if (opt) {
280 len = 0;
281 m = ip_insertoptions(m, opt, &len);
282 if (len != 0)
283 hlen = len;
284 }
285 ip = mtod(m, struct ip *);
286
287 /*
288 * Fill in IP header.
289 */
290 if (!(flags & (IP_FORWARDING|IP_RAWOUTPUT))) {
291 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, hlen >> 2);
292 ip->ip_off &= IP_DF;
293 if (ip_do_rfc6864 && (ip->ip_off & IP_DF))
294 ip->ip_id = 0;
295 else
296 ip->ip_id = ip_newid();
297 ipstat.ips_localout++;
298 } else {
299 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
300 }
301
302 reroute:
303 pkt_dst = next_hop ? next_hop->sin_addr : ip->ip_dst;
304
305 dst = (struct sockaddr_in *)&ro->ro_dst;
306 /*
307 * If there is a cached route,
308 * check that it is to the same destination
309 * and is still up. If not, free it and try again.
310 * The address family should also be checked in case of sharing the
311 * cache with IPv6.
312 */
313 if (ro->ro_rt &&
314 (!(ro->ro_rt->rt_flags & RTF_UP) ||
315 dst->sin_family != AF_INET ||
316 dst->sin_addr.s_addr != pkt_dst.s_addr)) {
317 rtfree(ro->ro_rt);
318 ro->ro_rt = NULL;
319 }
320 if (ro->ro_rt == NULL) {
321 bzero(dst, sizeof *dst);
322 dst->sin_family = AF_INET;
323 dst->sin_len = sizeof *dst;
324 dst->sin_addr = pkt_dst;
325 }
326 /*
327 * If routing to interface only,
328 * short circuit routing lookup.
329 */
330 if (flags & IP_ROUTETOIF) {
331 if ((ia = ifatoia(ifa_ifwithdstaddr(sintosa(dst)))) == NULL &&
332 (ia = ifatoia(ifa_ifwithnet(sintosa(dst)))) == NULL) {
333 ipstat.ips_noroute++;
334 error = ENETUNREACH;
335 goto bad;
336 }
337 ifp = ia->ia_ifp;
338 ip->ip_ttl = 1;
339 isbroadcast = in_broadcast(dst->sin_addr, ifp);
340 } else if (IN_MULTICAST(ntohl(pkt_dst.s_addr)) &&
341 imo != NULL && imo->imo_multicast_ifp != NULL) {
342 /*
343 * Bypass the normal routing lookup for multicast
344 * packets if the interface is specified.
345 */
346 ifp = imo->imo_multicast_ifp;
347 ia = IFP_TO_IA(ifp);
348 isbroadcast = 0; /* fool gcc */
349 } else {
350 /*
351 * If this is the case, we probably don't want to allocate
352 * a protocol-cloned route since we didn't get one from the
353 * ULP. This lets TCP do its thing, while not burdening
354 * forwarding or ICMP with the overhead of cloning a route.
355 * Of course, we still want to do any cloning requested by
356 * the link layer, as this is probably required in all cases
357 * for correct operation (as it is for ARP).
358 */
359 if (ro->ro_rt == NULL)
360 rtalloc_ign(ro, RTF_PRCLONING);
361 if (ro->ro_rt == NULL) {
362 ipstat.ips_noroute++;
363 error = EHOSTUNREACH;
364 goto bad;
365 }
366 ia = ifatoia(ro->ro_rt->rt_ifa);
367 ifp = ro->ro_rt->rt_ifp;
368 ro->ro_rt->rt_use++;
369 if (ro->ro_rt->rt_flags & RTF_GATEWAY)
370 dst = (struct sockaddr_in *)ro->ro_rt->rt_gateway;
371 if (ro->ro_rt->rt_flags & RTF_HOST)
372 isbroadcast = (ro->ro_rt->rt_flags & RTF_BROADCAST);
373 else
374 isbroadcast = in_broadcast(dst->sin_addr, ifp);
375 }
376 if (IN_MULTICAST(ntohl(pkt_dst.s_addr))) {
377 m->m_flags |= M_MCAST;
378 /*
379 * IP destination address is multicast. Make sure "dst"
380 * still points to the address in "ro". (It may have been
381 * changed to point to a gateway address, above.)
382 */
383 dst = (struct sockaddr_in *)&ro->ro_dst;
384 /*
385 * See if the caller provided any multicast options
386 */
387 if (imo != NULL) {
388 ip->ip_ttl = imo->imo_multicast_ttl;
389 if (imo->imo_multicast_vif != -1) {
390 ip->ip_src.s_addr =
391 ip_mcast_src ?
392 ip_mcast_src(imo->imo_multicast_vif) :
393 INADDR_ANY;
394 }
395 } else {
396 ip->ip_ttl = IP_DEFAULT_MULTICAST_TTL;
397 }
398 /*
399 * Confirm that the outgoing interface supports multicast.
400 */
401 if ((imo == NULL) || (imo->imo_multicast_vif == -1)) {
402 if (!(ifp->if_flags & IFF_MULTICAST)) {
403 ipstat.ips_noroute++;
404 error = ENETUNREACH;
405 goto bad;
406 }
407 }
408 /*
409 * If source address not specified yet, use address of the
410 * outgoing interface. In case, keep note we did that, so
411 * if the the firewall changes the next-hop causing the
412 * output interface to change, we can fix that.
413 */
414 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
415 /* Interface may have no addresses. */
416 if (ia != NULL) {
417 ip->ip_src = IA_SIN(ia)->sin_addr;
418 src_was_INADDR_ANY = 1;
419 }
420 }
421
422 if (ip->ip_src.s_addr != INADDR_ANY) {
423 struct in_multi *inm;
424
425 inm = IN_LOOKUP_MULTI(&pkt_dst, ifp);
426 if (inm != NULL &&
427 (imo == NULL || imo->imo_multicast_loop)) {
428 /*
429 * If we belong to the destination multicast
430 * group on the outgoing interface, and the
431 * caller did not forbid loopback, loop back
432 * a copy.
433 */
434 ip_mloopback(ifp, m, dst, hlen);
435 } else {
436 /*
437 * If we are acting as a multicast router,
438 * perform multicast forwarding as if the
439 * packet had just arrived on the interface
440 * to which we are about to send. The
441 * multicast forwarding function recursively
442 * calls this function, using the IP_FORWARDING
443 * flag to prevent infinite recursion.
444 *
445 * Multicasts that are looped back by
446 * ip_mloopback(), above, will be forwarded by
447 * the ip_input() routine, if necessary.
448 */
449 if (ip_mrouter && !(flags & IP_FORWARDING)) {
450 /*
451 * If rsvp daemon is not running, do
452 * not set ip_moptions. This ensures
453 * that the packet is multicast and
454 * not just sent down one link as
455 * prescribed by rsvpd.
456 */
457 if (!rsvp_on)
458 imo = NULL;
459 if (ip_mforward) {
460 get_mplock();
461 if (ip_mforward(ip, ifp,
462 m, imo) != 0) {
463 m_freem(m);
464 rel_mplock();
465 goto done;
466 }
467 rel_mplock();
468 }
469 }
470 }
471 }
472
473 /*
474 * Multicasts with a time-to-live of zero may be looped-
475 * back, above, but must not be transmitted on a network.
476 * Also, multicasts addressed to the loopback interface
477 * are not sent -- the above call to ip_mloopback() will
478 * loop back a copy if this host actually belongs to the
479 * destination group on the loopback interface.
480 */
481 if (ip->ip_ttl == 0 || ifp->if_flags & IFF_LOOPBACK) {
482 m_freem(m);
483 goto done;
484 }
485
486 goto sendit;
487 } else {
488 m->m_flags &= ~M_MCAST;
489 }
490
491 /*
492 * If the source address is not specified yet, use the address
493 * of the outgoing interface. In case, keep note we did that,
494 * so if the the firewall changes the next-hop causing the output
495 * interface to change, we can fix that.
496 */
497 if (ip->ip_src.s_addr == INADDR_ANY || src_was_INADDR_ANY) {
498 /* Interface may have no addresses. */
499 if (ia != NULL) {
500 ip->ip_src = IA_SIN(ia)->sin_addr;
501 src_was_INADDR_ANY = 1;
502 }
503 }
504
505 /*
506 * Look for broadcast address and
507 * verify user is allowed to send
508 * such a packet.
509 */
510 if (isbroadcast) {
511 if (!(ifp->if_flags & IFF_BROADCAST)) {
512 error = EADDRNOTAVAIL;
513 goto bad;
514 }
515 if (!(flags & IP_ALLOWBROADCAST)) {
516 error = EACCES;
517 goto bad;
518 }
519 /* don't allow broadcast messages to be fragmented */
520 if (ip->ip_len > ifp->if_mtu) {
521 error = EMSGSIZE;
522 goto bad;
523 }
524 m->m_flags |= M_BCAST;
525 } else {
526 m->m_flags &= ~M_BCAST;
527 }
528
529 sendit:
530 #ifdef IPSEC
531 /* get SP for this packet */
532 if (so == NULL)
533 sp = ipsec4_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, flags, &error);
534 else
535 sp = ipsec4_getpolicybysock(m, IPSEC_DIR_OUTBOUND, so, &error);
536
537 if (sp == NULL) {
538 ipsecstat.out_inval++;
539 goto bad;
540 }
541
542 error = 0;
543
544 /* check policy */
545 switch (sp->policy) {
546 case IPSEC_POLICY_DISCARD:
547 /*
548 * This packet is just discarded.
549 */
550 ipsecstat.out_polvio++;
551 goto bad;
552
553 case IPSEC_POLICY_BYPASS:
554 case IPSEC_POLICY_NONE:
555 case IPSEC_POLICY_TCP:
556 /* no need to do IPsec. */
557 goto skip_ipsec;
558
559 case IPSEC_POLICY_IPSEC:
560 if (sp->req == NULL) {
561 /* acquire a policy */
562 error = key_spdacquire(sp);
563 goto bad;
564 }
565 break;
566
567 case IPSEC_POLICY_ENTRUST:
568 default:
569 kprintf("ip_output: Invalid policy found. %d\n", sp->policy);
570 }
571 {
572 struct ipsec_output_state state;
573 bzero(&state, sizeof state);
574 state.m = m;
575 if (flags & IP_ROUTETOIF) {
576 state.ro = &iproute;
577 bzero(&iproute, sizeof iproute);
578 } else
579 state.ro = ro;
580 state.dst = (struct sockaddr *)dst;
581
582 ip->ip_sum = 0;
583
584 /*
585 * XXX
586 * delayed checksums are not currently compatible with IPsec
587 */
588 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
589 in_delayed_cksum(m);
590 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
591 }
592
593 ip->ip_len = htons(ip->ip_len);
594 ip->ip_off = htons(ip->ip_off);
595
596 error = ipsec4_output(&state, sp, flags);
597
598 m = state.m;
599 if (flags & IP_ROUTETOIF) {
600 /*
601 * if we have tunnel mode SA, we may need to ignore
602 * IP_ROUTETOIF.
603 */
604 if (state.ro != &iproute || state.ro->ro_rt != NULL) {
605 flags &= ~IP_ROUTETOIF;
606 ro = state.ro;
607 }
608 } else
609 ro = state.ro;
610 dst = (struct sockaddr_in *)state.dst;
611 if (error) {
612 /* mbuf is already reclaimed in ipsec4_output. */
613 m0 = NULL;
614 switch (error) {
615 case EHOSTUNREACH:
616 case ENETUNREACH:
617 case EMSGSIZE:
618 case ENOBUFS:
619 case ENOMEM:
620 break;
621 default:
622 kprintf("ip4_output (ipsec): error code %d\n", error);
623 /*fall through*/
624 case ENOENT:
625 /* don't show these error codes to the user */
626 error = 0;
627 break;
628 }
629 goto bad;
630 }
631 }
632
633 /* be sure to update variables that are affected by ipsec4_output() */
634 ip = mtod(m, struct ip *);
635 #ifdef _IP_VHL
636 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
637 #else
638 hlen = ip->ip_hl << 2;
639 #endif
640 if (ro->ro_rt == NULL) {
641 if (!(flags & IP_ROUTETOIF)) {
642 kprintf("ip_output: "
643 "can't update route after IPsec processing\n");
644 error = EHOSTUNREACH; /*XXX*/
645 goto bad;
646 }
647 } else {
648 ia = ifatoia(ro->ro_rt->rt_ifa);
649 ifp = ro->ro_rt->rt_ifp;
650 }
651
652 /* make it flipped, again. */
653 ip->ip_len = ntohs(ip->ip_len);
654 ip->ip_off = ntohs(ip->ip_off);
655 skip_ipsec:
656 #endif /*IPSEC*/
657 #ifdef FAST_IPSEC
658 /*
659 * Check the security policy (SP) for the packet and, if
660 * required, do IPsec-related processing. There are two
661 * cases here; the first time a packet is sent through
662 * it will be untagged and handled by ipsec4_checkpolicy.
663 * If the packet is resubmitted to ip_output (e.g. after
664 * AH, ESP, etc. processing), there will be a tag to bypass
665 * the lookup and related policy checking.
666 */
667 mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
668 crit_enter();
669 if (mtag != NULL) {
670 tdbi = (struct tdb_ident *)m_tag_data(mtag);
671 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
672 if (sp == NULL)
673 error = -EINVAL; /* force silent drop */
674 m_tag_delete(m, mtag);
675 } else {
676 sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags,
677 &error, inp);
678 }
679 /*
680 * There are four return cases:
681 * sp != NULL apply IPsec policy
682 * sp == NULL, error == 0 no IPsec handling needed
683 * sp == NULL, error == -EINVAL discard packet w/o error
684 * sp == NULL, error != 0 discard packet, report error
685 */
686 if (sp != NULL) {
687 /* Loop detection, check if ipsec processing already done */
688 KASSERT(sp->req != NULL, ("ip_output: no ipsec request"));
689 for (mtag = m_tag_first(m); mtag != NULL;
690 mtag = m_tag_next(m, mtag)) {
691 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
692 continue;
693 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
694 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
695 continue;
696 /*
697 * Check if policy has an SA associated with it.
698 * This can happen when an SP has yet to acquire
699 * an SA; e.g. on first reference. If it occurs,
700 * then we let ipsec4_process_packet do its thing.
701 */
702 if (sp->req->sav == NULL)
703 break;
704 tdbi = (struct tdb_ident *)m_tag_data(mtag);
705 if (tdbi->spi == sp->req->sav->spi &&
706 tdbi->proto == sp->req->sav->sah->saidx.proto &&
707 bcmp(&tdbi->dst, &sp->req->sav->sah->saidx.dst,
708 sizeof(union sockaddr_union)) == 0) {
709 /*
710 * No IPsec processing is needed, free
711 * reference to SP.
712 *
713 * NB: null pointer to avoid free at
714 * done: below.
715 */
716 KEY_FREESP(&sp), sp = NULL;
717 crit_exit();
718 goto spd_done;
719 }
720 }
721
722 /*
723 * Do delayed checksums now because we send before
724 * this is done in the normal processing path.
725 */
726 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
727 in_delayed_cksum(m);
728 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
729 }
730
731 ip->ip_len = htons(ip->ip_len);
732 ip->ip_off = htons(ip->ip_off);
733
734 /* NB: callee frees mbuf */
735 error = ipsec4_process_packet(m, sp->req, flags, 0);
736 /*
737 * Preserve KAME behaviour: ENOENT can be returned
738 * when an SA acquire is in progress. Don't propagate
739 * this to user-level; it confuses applications.
740 *
741 * XXX this will go away when the SADB is redone.
742 */
743 if (error == ENOENT)
744 error = 0;
745 crit_exit();
746 goto done;
747 } else {
748 crit_exit();
749
750 if (error != 0) {
751 /*
752 * Hack: -EINVAL is used to signal that a packet
753 * should be silently discarded. This is typically
754 * because we asked key management for an SA and
755 * it was delayed (e.g. kicked up to IKE).
756 */
757 if (error == -EINVAL)
758 error = 0;
759 goto bad;
760 } else {
761 /* No IPsec processing for this packet. */
762 }
763 #ifdef notyet
764 /*
765 * If deferred crypto processing is needed, check that
766 * the interface supports it.
767 */
768 mtag = m_tag_find(m, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL);
769 if (mtag != NULL && !(ifp->if_capenable & IFCAP_IPSEC)) {
770 /* notify IPsec to do its own crypto */
771 ipsp_skipcrypto_unmark((struct tdb_ident *)m_tag_data(mtag));
772 error = EHOSTUNREACH;
773 goto bad;
774 }
775 #endif
776 }
777 spd_done:
778 #endif /* FAST_IPSEC */
779
780 /* We are already being fwd'd from a firewall. */
781 if (next_hop != NULL)
782 goto pass;
783
784 /* No pfil hooks */
785 if (!pfil_has_hooks(&inet_pfil_hook)) {
786 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
787 /*
788 * Strip dummynet tags from stranded packets
789 */
790 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
791 KKASSERT(mtag != NULL);
792 m_tag_delete(m, mtag);
793 m->m_pkthdr.fw_flags &= ~DUMMYNET_MBUF_TAGGED;
794 }
795 goto pass;
796 }
797
798 /*
799 * IpHack's section.
800 * - Xlate: translate packet's addr/port (NAT).
801 * - Firewall: deny/allow/etc.
802 * - Wrap: fake packet's addr/port <unimpl.>
803 * - Encapsulate: put it in another IP and send out. <unimp.>
804 */
805
806 /*
807 * Run through list of hooks for output packets.
808 */
809 error = pfil_run_hooks(&inet_pfil_hook, &m, ifp, PFIL_OUT);
810 if (error != 0 || m == NULL)
811 goto done;
812 ip = mtod(m, struct ip *);
813
814 if (m->m_pkthdr.fw_flags & IPFORWARD_MBUF_TAGGED) {
815 /*
816 * Check dst to make sure it is directly reachable on the
817 * interface we previously thought it was.
818 * If it isn't (which may be likely in some situations) we have
819 * to re-route it (ie, find a route for the next-hop and the
820 * associated interface) and set them here. This is nested
821 * forwarding which in most cases is undesirable, except where
822 * such control is nigh impossible. So we do it here.
823 * And I'm babbling.
824 */
825 mtag = m_tag_find(m, PACKET_TAG_IPFORWARD, NULL);
826 KKASSERT(mtag != NULL);
827 next_hop = m_tag_data(mtag);
828
829 /*
830 * Try local forwarding first
831 */
832 if (ip_localforward(m, next_hop, hlen))
833 goto done;
834
835 /*
836 * Relocate the route based on next_hop.
837 * If the current route is inp's cache, keep it untouched.
838 */
839 if (ro == &iproute && ro->ro_rt != NULL) {
840 RTFREE(ro->ro_rt);
841 ro->ro_rt = NULL;
842 }
843 ro = &iproute;
844 bzero(ro, sizeof *ro);
845
846 /*
847 * Forwarding to broadcast address is not allowed.
848 * XXX Should we follow IP_ROUTETOIF?
849 */
850 flags &= ~(IP_ALLOWBROADCAST | IP_ROUTETOIF);
851
852 /* We are doing forwarding now */
853 flags |= IP_FORWARDING;
854
855 goto reroute;
856 }
857
858 if (m->m_pkthdr.fw_flags & DUMMYNET_MBUF_TAGGED) {
859 struct dn_pkt *dn_pkt;
860
861 mtag = m_tag_find(m, PACKET_TAG_DUMMYNET, NULL);
862 KKASSERT(mtag != NULL);
863 dn_pkt = m_tag_data(mtag);
864
865 /*
866 * Under certain cases it is not possible to recalculate
867 * 'ro' and 'dst', let alone 'flags', so just save them in
868 * dummynet tag and avoid the possible wrong reculcalation
869 * when we come back to ip_output() again.
870 *
871 * All other parameters have been already used and so they
872 * are not needed anymore.
873 * XXX if the ifp is deleted while a pkt is in dummynet,
874 * we are in trouble! (TODO use ifnet_detach_event)
875 *
876 * We need to copy *ro because for ICMP pkts (and maybe
877 * others) the caller passed a pointer into the stack;
878 * dst might also be a pointer into *ro so it needs to
879 * be updated.
880 */
881 dn_pkt->ro = *ro;
882 if (ro->ro_rt)
883 ro->ro_rt->rt_refcnt++;
884 if (dst == (struct sockaddr_in *)&ro->ro_dst) {
885 /* 'dst' points into 'ro' */
886 dst = (struct sockaddr_in *)&(dn_pkt->ro.ro_dst);
887 }
888 dn_pkt->dn_dst = dst;
889 dn_pkt->flags = flags;
890
891 ip_dn_queue(m);
892 goto done;
893 }
894
895 if (m->m_pkthdr.fw_flags & IPFW_MBUF_CONTINUE) {
896 /* ipfw was disabled/unloaded. */
897 m_freem(m);
898 goto done;
899 }
900 pass:
901 /* 127/8 must not appear on wire - RFC1122. */
902 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET ||
903 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) {
904 if (!(ifp->if_flags & IFF_LOOPBACK)) {
905 ipstat.ips_badaddr++;
906 error = EADDRNOTAVAIL;
907 goto bad;
908 }
909 }
910 if (ip->ip_src.s_addr == INADDR_ANY ||
911 IN_MULTICAST(ntohl(ip->ip_src.s_addr))) {
912 ipstat.ips_badaddr++;
913 error = EADDRNOTAVAIL;
914 goto bad;
915 }
916
917 if ((m->m_pkthdr.csum_flags & CSUM_TSO) == 0) {
918 m->m_pkthdr.csum_flags |= CSUM_IP;
919 sw_csum = m->m_pkthdr.csum_flags & ~ifp->if_hwassist;
920 if (sw_csum & CSUM_DELAY_DATA) {
921 in_delayed_cksum(m);
922 sw_csum &= ~CSUM_DELAY_DATA;
923 }
924 m->m_pkthdr.csum_flags &= ifp->if_hwassist;
925 } else {
926 sw_csum = 0;
927 }
928 m->m_pkthdr.csum_iphlen = hlen;
929
930 /*
931 * If small enough for interface, or the interface will take
932 * care of the fragmentation or segmentation for us, can just
933 * send directly.
934 */
935 if (ip->ip_len <= ifp->if_mtu ||
936 ((ifp->if_hwassist & CSUM_FRAGMENT) && !(ip->ip_off & IP_DF)) ||
937 (m->m_pkthdr.csum_flags & CSUM_TSO)) {
938 ip->ip_len = htons(ip->ip_len);
939 ip->ip_off = htons(ip->ip_off);
940 ip->ip_sum = 0;
941 if (sw_csum & CSUM_DELAY_IP) {
942 if (ip->ip_vhl == IP_VHL_BORING)
943 ip->ip_sum = in_cksum_hdr(ip);
944 else
945 ip->ip_sum = in_cksum(m, hlen);
946 }
947
948 /* Record statistics for this interface address. */
949 if (!(flags & IP_FORWARDING) && ia) {
950 IFA_STAT_INC(&ia->ia_ifa, opackets, 1);
951 IFA_STAT_INC(&ia->ia_ifa, obytes, m->m_pkthdr.len);
952 }
953
954 #ifdef IPSEC
955 /* clean ipsec history once it goes out of the node */
956 ipsec_delaux(m);
957 #endif
958
959 #ifdef MBUF_STRESS_TEST
960 if (mbuf_frag_size && m->m_pkthdr.len > mbuf_frag_size) {
961 struct mbuf *m1, *m2;
962 int length, tmp;
963
964 tmp = length = m->m_pkthdr.len;
965
966 while ((length -= mbuf_frag_size) >= 1) {
967 m1 = m_split(m, length, M_NOWAIT);
968 if (m1 == NULL)
969 break;
970 m2 = m;
971 while (m2->m_next != NULL)
972 m2 = m2->m_next;
973 m2->m_next = m1;
974 }
975 m->m_pkthdr.len = tmp;
976 }
977 #endif
978
979 #ifdef MPLS
980 if (!mpls_output_process(m, ro->ro_rt))
981 goto done;
982 #endif
983 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
984 ro->ro_rt);
985 goto done;
986 }
987
988 if (ip->ip_off & IP_DF) {
989 error = EMSGSIZE;
990 /*
991 * This case can happen if the user changed the MTU
992 * of an interface after enabling IP on it. Because
993 * most netifs don't keep track of routes pointing to
994 * them, there is no way for one to update all its
995 * routes when the MTU is changed.
996 */
997 if ((ro->ro_rt->rt_flags & (RTF_UP | RTF_HOST)) &&
998 !(ro->ro_rt->rt_rmx.rmx_locks & RTV_MTU) &&
999 (ro->ro_rt->rt_rmx.rmx_mtu > ifp->if_mtu)) {
1000 ro->ro_rt->rt_rmx.rmx_mtu = ifp->if_mtu;
1001 }
1002 ipstat.ips_cantfrag++;
1003 goto bad;
1004 }
1005
1006 /*
1007 * Too large for interface; fragment if possible. If successful,
1008 * on return, m will point to a list of packets to be sent.
1009 */
1010 error = ip_fragment(ip, &m, ifp->if_mtu, ifp->if_hwassist, sw_csum);
1011 if (error)
1012 goto bad;
1013 for (; m; m = m0) {
1014 m0 = m->m_nextpkt;
1015 m->m_nextpkt = NULL;
1016 #ifdef IPSEC
1017 /* clean ipsec history once it goes out of the node */
1018 ipsec_delaux(m);
1019 #endif
1020 if (error == 0) {
1021 /* Record statistics for this interface address. */
1022 if (ia != NULL) {
1023 IFA_STAT_INC(&ia->ia_ifa, opackets, 1);
1024 IFA_STAT_INC(&ia->ia_ifa, obytes,
1025 m->m_pkthdr.len);
1026 }
1027 #ifdef MPLS
1028 if (!mpls_output_process(m, ro->ro_rt))
1029 continue;
1030 #endif
1031 error = ifp->if_output(ifp, m, (struct sockaddr *)dst,
1032 ro->ro_rt);
1033 } else {
1034 m_freem(m);
1035 }
1036 }
1037
1038 if (error == 0)
1039 ipstat.ips_fragmented++;
1040
1041 done:
1042 if (ro == &iproute && ro->ro_rt != NULL) {
1043 RTFREE(ro->ro_rt);
1044 ro->ro_rt = NULL;
1045 }
1046 #ifdef IPSEC
1047 if (sp != NULL) {
1048 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1049 kprintf("DP ip_output call free SP:%p\n", sp));
1050 key_freesp(sp);
1051 }
1052 #endif
1053 #ifdef FAST_IPSEC
1054 if (sp != NULL)
1055 KEY_FREESP(&sp);
1056 #endif
1057 return (error);
1058 bad:
1059 m_freem(m);
1060 goto done;
1061 }
1062
1063 /*
1064 * Create a chain of fragments which fit the given mtu. m_frag points to the
1065 * mbuf to be fragmented; on return it points to the chain with the fragments.
1066 * Return 0 if no error. If error, m_frag may contain a partially built
1067 * chain of fragments that should be freed by the caller.
1068 *
1069 * if_hwassist_flags is the hw offload capabilities (see if_data.ifi_hwassist)
1070 * sw_csum contains the delayed checksums flags (e.g., CSUM_DELAY_IP).
1071 */
1072 int
1073 ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
1074 u_long if_hwassist_flags, int sw_csum)
1075 {
1076 int error = 0;
1077 int hlen = IP_VHL_HL(ip->ip_vhl) << 2;
1078 int len = (mtu - hlen) & ~7; /* size of payload in each fragment */
1079 int off;
1080 struct mbuf *m0 = *m_frag; /* the original packet */
1081 int firstlen;
1082 struct mbuf **mnext;
1083 int nfrags;
1084
1085 if (ip->ip_off & IP_DF) { /* Fragmentation not allowed */
1086 ipstat.ips_cantfrag++;
1087 return EMSGSIZE;
1088 }
1089
1090 /*
1091 * Must be able to put at least 8 bytes per fragment.
1092 */
1093 if (len < 8)
1094 return EMSGSIZE;
1095
1096 /*
1097 * If the interface will not calculate checksums on
1098 * fragmented packets, then do it here.
1099 */
1100 if ((m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA) &&
1101 !(if_hwassist_flags & CSUM_IP_FRAGS)) {
1102 in_delayed_cksum(m0);
1103 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
1104 }
1105
1106 if (len > PAGE_SIZE) {
1107 /*
1108 * Fragment large datagrams such that each segment
1109 * contains a multiple of PAGE_SIZE amount of data,
1110 * plus headers. This enables a receiver to perform
1111 * page-flipping zero-copy optimizations.
1112 *
1113 * XXX When does this help given that sender and receiver
1114 * could have different page sizes, and also mtu could
1115 * be less than the receiver's page size ?
1116 */
1117 int newlen;
1118 struct mbuf *m;
1119
1120 for (m = m0, off = 0; m && (off+m->m_len) <= mtu; m = m->m_next)
1121 off += m->m_len;
1122
1123 /*
1124 * firstlen (off - hlen) must be aligned on an
1125 * 8-byte boundary
1126 */
1127 if (off < hlen)
1128 goto smart_frag_failure;
1129 off = ((off - hlen) & ~7) + hlen;
1130 newlen = (~PAGE_MASK) & mtu;
1131 if ((newlen + sizeof(struct ip)) > mtu) {
1132 /* we failed, go back the default */
1133 smart_frag_failure:
1134 newlen = len;
1135 off = hlen + len;
1136 }
1137 len = newlen;
1138
1139 } else {
1140 off = hlen + len;
1141 }
1142
1143 firstlen = off - hlen;
1144 mnext = &m0->m_nextpkt; /* pointer to next packet */
1145
1146 /*
1147 * Loop through length of segment after first fragment,
1148 * make new header and copy data of each part and link onto chain.
1149 * Here, m0 is the original packet, m is the fragment being created.
1150 * The fragments are linked off the m_nextpkt of the original
1151 * packet, which after processing serves as the first fragment.
1152 */
1153 for (nfrags = 1; off < ip->ip_len; off += len, nfrags++) {
1154 struct ip *mhip; /* ip header on the fragment */
1155 struct mbuf *m;
1156 int mhlen = sizeof(struct ip);
1157
1158 MGETHDR(m, M_NOWAIT, MT_HEADER);
1159 if (m == NULL) {
1160 error = ENOBUFS;
1161 ipstat.ips_odropped++;
1162 goto done;
1163 }
1164 m->m_flags |= (m0->m_flags & M_MCAST) | M_FRAG;
1165 /*
1166 * In the first mbuf, leave room for the link header, then
1167 * copy the original IP header including options. The payload
1168 * goes into an additional mbuf chain returned by m_copy().
1169 */
1170 m->m_data += max_linkhdr;
1171 mhip = mtod(m, struct ip *);
1172 *mhip = *ip;
1173 if (hlen > sizeof(struct ip)) {
1174 mhlen = ip_optcopy(ip, mhip) + sizeof(struct ip);
1175 mhip->ip_vhl = IP_MAKE_VHL(IPVERSION, mhlen >> 2);
1176 }
1177 m->m_len = mhlen;
1178 /* XXX do we need to add ip->ip_off below ? */
1179 mhip->ip_off = ((off - hlen) >> 3) + ip->ip_off;
1180 if (off + len >= ip->ip_len) { /* last fragment */
1181 len = ip->ip_len - off;
1182 m->m_flags |= M_LASTFRAG;
1183 } else
1184 mhip->ip_off |= IP_MF;
1185 mhip->ip_len = htons((u_short)(len + mhlen));
1186 m->m_next = m_copy(m0, off, len);
1187 if (m->m_next == NULL) { /* copy failed */
1188 m_free(m);
1189 error = ENOBUFS; /* ??? */
1190 ipstat.ips_odropped++;
1191 goto done;
1192 }
1193 m->m_pkthdr.len = mhlen + len;
1194 m->m_pkthdr.rcvif = NULL;
1195 m->m_pkthdr.csum_flags = m0->m_pkthdr.csum_flags;
1196 m->m_pkthdr.csum_iphlen = mhlen;
1197 mhip->ip_off = htons(mhip->ip_off);
1198 mhip->ip_sum = 0;
1199 if (sw_csum & CSUM_DELAY_IP)
1200 mhip->ip_sum = in_cksum(m, mhlen);
1201 *mnext = m;
1202 mnext = &m->m_nextpkt;
1203 }
1204 ipstat.ips_ofragments += nfrags;
1205
1206 /* set first marker for fragment chain */
1207 m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1208 m0->m_pkthdr.csum_data = nfrags;
1209
1210 /*
1211 * Update first fragment by trimming what's been copied out
1212 * and updating header.
1213 */
1214 m_adj(m0, hlen + firstlen - ip->ip_len);
1215 m0->m_pkthdr.len = hlen + firstlen;
1216 ip->ip_len = htons((u_short)m0->m_pkthdr.len);
1217 ip->ip_off |= IP_MF;
1218 ip->ip_off = htons(ip->ip_off);
1219 ip->ip_sum = 0;
1220 if (sw_csum & CSUM_DELAY_IP)
1221 ip->ip_sum = in_cksum(m0, hlen);
1222
1223 done:
1224 *m_frag = m0;
1225 return error;
1226 }
1227
1228 void
1229 in_delayed_cksum(struct mbuf *m)
1230 {
1231 struct ip *ip;
1232 u_short csum, offset;
1233
1234 ip = mtod(m, struct ip *);
1235 offset = IP_VHL_HL(ip->ip_vhl) << 2 ;
1236 csum = in_cksum_skip(m, ip->ip_len, offset);
1237 if (m->m_pkthdr.csum_flags & CSUM_UDP && csum == 0)
1238 csum = 0xffff;
1239 offset += m->m_pkthdr.csum_data; /* checksum offset */
1240
1241 if (offset + sizeof(u_short) > m->m_len) {
1242 kprintf("delayed m_pullup, m->len: %d off: %d p: %d\n",
1243 m->m_len, offset, ip->ip_p);
1244 /*
1245 * XXX
1246 * this shouldn't happen, but if it does, the
1247 * correct behavior may be to insert the checksum
1248 * in the existing chain instead of rearranging it.
1249 */
1250 m = m_pullup(m, offset + sizeof(u_short));
1251 }
1252 *(u_short *)(m->m_data + offset) = csum;
1253 }
1254
1255 /*
1256 * Insert IP options into preformed packet.
1257 * Adjust IP destination as required for IP source routing,
1258 * as indicated by a non-zero in_addr at the start of the options.
1259 *
1260 * XXX This routine assumes that the packet has no options in place.
1261 */
1262 static struct mbuf *
1263 ip_insertoptions(struct mbuf *m, struct mbuf *opt, int *phlen)
1264 {
1265 struct ipoption *p = mtod(opt, struct ipoption *);
1266 struct mbuf *n;
1267 struct ip *ip = mtod(m, struct ip *);
1268 unsigned optlen;
1269
1270 optlen = opt->m_len - sizeof p->ipopt_dst;
1271 if (optlen + (u_short)ip->ip_len > IP_MAXPACKET) {
1272 *phlen = 0;
1273 return (m); /* XXX should fail */
1274 }
1275 if (p->ipopt_dst.s_addr)
1276 ip->ip_dst = p->ipopt_dst;
1277 if (m->m_flags & M_EXT || m->m_data - optlen < m->m_pktdat) {
1278 MGETHDR(n, M_NOWAIT, MT_HEADER);
1279 if (n == NULL) {
1280 *phlen = 0;
1281 return (m);
1282 }
1283 n->m_pkthdr.rcvif = NULL;
1284 n->m_pkthdr.len = m->m_pkthdr.len + optlen;
1285 m->m_len -= sizeof(struct ip);
1286 m->m_data += sizeof(struct ip);
1287 n->m_next = m;
1288 m = n;
1289 m->m_len = optlen + sizeof(struct ip);
1290 m->m_data += max_linkhdr;
1291 memcpy(mtod(m, void *), ip, sizeof(struct ip));
1292 } else {
1293 m->m_data -= optlen;
1294 m->m_len += optlen;
1295 m->m_pkthdr.len += optlen;
1296 bcopy(ip, mtod(m, caddr_t), sizeof(struct ip));
1297 }
1298 ip = mtod(m, struct ip *);
1299 bcopy(p->ipopt_list, ip + 1, optlen);
1300 *phlen = sizeof(struct ip) + optlen;
1301 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, *phlen >> 2);
1302 ip->ip_len += optlen;
1303 return (m);
1304 }
1305
1306 /*
1307 * Copy options from ip to jp,
1308 * omitting those not copied during fragmentation.
1309 */
1310 int
1311 ip_optcopy(struct ip *ip, struct ip *jp)
1312 {
1313 u_char *cp, *dp;
1314 int opt, optlen, cnt;
1315
1316 cp = (u_char *)(ip + 1);
1317 dp = (u_char *)(jp + 1);
1318 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof(struct ip);
1319 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1320 opt = cp[0];
1321 if (opt == IPOPT_EOL)
1322 break;
1323 if (opt == IPOPT_NOP) {
1324 /* Preserve for IP mcast tunnel's LSRR alignment. */
1325 *dp++ = IPOPT_NOP;
1326 optlen = 1;
1327 continue;
1328 }
1329
1330 KASSERT(cnt >= IPOPT_OLEN + sizeof *cp,
1331 ("ip_optcopy: malformed ipv4 option"));
1332 optlen = cp[IPOPT_OLEN];
1333 KASSERT(optlen >= IPOPT_OLEN + sizeof *cp && optlen <= cnt,
1334 ("ip_optcopy: malformed ipv4 option"));
1335
1336 /* bogus lengths should have been caught by ip_dooptions */
1337 if (optlen > cnt)
1338 optlen = cnt;
1339 if (IPOPT_COPIED(opt)) {
1340 bcopy(cp, dp, optlen);
1341 dp += optlen;
1342 }
1343 }
1344 for (optlen = dp - (u_char *)(jp+1); optlen & 0x3; optlen++)
1345 *dp++ = IPOPT_EOL;
1346 return (optlen);
1347 }
1348
1349 /*
1350 * IP socket option processing.
1351 */
1352 void
1353 ip_ctloutput(netmsg_t msg)
1354 {
1355 struct socket *so = msg->base.nm_so;
1356 struct sockopt *sopt = msg->ctloutput.nm_sopt;
1357 struct inpcb *inp = so->so_pcb;
1358 int error, optval;
1359
1360 error = optval = 0;
1361
1362 /* Get socket's owner cpuid hint */
1363 if (sopt->sopt_level == SOL_SOCKET &&
1364 sopt->sopt_dir == SOPT_GET &&
1365 sopt->sopt_name == SO_CPUHINT) {
1366 optval = mycpuid;
1367 soopt_from_kbuf(sopt, &optval, sizeof(optval));
1368 goto done;
1369 }
1370
1371 if (sopt->sopt_level != IPPROTO_IP) {
1372 error = EINVAL;
1373 goto done;
1374 }
1375
1376 switch (sopt->sopt_name) {
1377 case IP_MULTICAST_IF:
1378 case IP_MULTICAST_VIF:
1379 case IP_MULTICAST_TTL:
1380 case IP_MULTICAST_LOOP:
1381 case IP_ADD_MEMBERSHIP:
1382 case IP_DROP_MEMBERSHIP:
1383 /*
1384 * Handle multicast options in netisr0
1385 */
1386 if (&curthread->td_msgport != netisr_cpuport(0)) {
1387 /* NOTE: so_port MUST NOT be checked in netisr0 */
1388 msg->lmsg.ms_flags |= MSGF_IGNSOPORT;
1389 lwkt_forwardmsg(netisr_cpuport(0), &msg->lmsg);
1390 return;
1391 }
1392 break;
1393 }
1394
1395 switch (sopt->sopt_dir) {
1396 case SOPT_SET:
1397 switch (sopt->sopt_name) {
1398 case IP_OPTIONS:
1399 #ifdef notyet
1400 case IP_RETOPTS:
1401 #endif
1402 {
1403 struct mbuf *m;
1404 if (sopt->sopt_valsize > MLEN) {
1405 error = EMSGSIZE;
1406 break;
1407 }
1408 MGET(m, sopt->sopt_td ? M_WAITOK : M_NOWAIT, MT_HEADER);
1409 if (m == NULL) {
1410 error = ENOBUFS;
1411 break;
1412 }
1413 m->m_len = sopt->sopt_valsize;
1414 error = soopt_to_kbuf(sopt, mtod(m, void *), m->m_len,
1415 m->m_len);
1416 error = ip_pcbopts(sopt->sopt_name,
1417 &inp->inp_options, m);
1418 goto done;
1419 }
1420
1421 case IP_TOS:
1422 case IP_TTL:
1423 case IP_MINTTL:
1424 case IP_RECVOPTS:
1425 case IP_RECVRETOPTS:
1426 case IP_RECVDSTADDR:
1427 case IP_RECVIF:
1428 case IP_RECVTTL:
1429 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1430 sizeof optval);
1431 if (error)
1432 break;
1433 switch (sopt->sopt_name) {
1434 case IP_TOS:
1435 inp->inp_ip_tos = optval;
1436 break;
1437
1438 case IP_TTL:
1439 inp->inp_ip_ttl = optval;
1440 break;
1441 case IP_MINTTL:
1442 if (optval >= 0 && optval <= MAXTTL)
1443 inp->inp_ip_minttl = optval;
1444 else
1445 error = EINVAL;
1446 break;
1447 #define OPTSET(bit) \
1448 if (optval) \
1449 inp->inp_flags |= bit; \
1450 else \
1451 inp->inp_flags &= ~bit;
1452
1453 case IP_RECVOPTS:
1454 OPTSET(INP_RECVOPTS);
1455 break;
1456
1457 case IP_RECVRETOPTS:
1458 OPTSET(INP_RECVRETOPTS);
1459 break;
1460
1461 case IP_RECVDSTADDR:
1462 OPTSET(INP_RECVDSTADDR);
1463 break;
1464
1465 case IP_RECVIF:
1466 OPTSET(INP_RECVIF);
1467 break;
1468
1469 case IP_RECVTTL:
1470 OPTSET(INP_RECVTTL);
1471 break;
1472 }
1473 break;
1474 #undef OPTSET
1475
1476 case IP_MULTICAST_IF:
1477 case IP_MULTICAST_VIF:
1478 case IP_MULTICAST_TTL:
1479 case IP_MULTICAST_LOOP:
1480 case IP_ADD_MEMBERSHIP:
1481 case IP_DROP_MEMBERSHIP:
1482 error = ip_setmoptions(sopt, &inp->inp_moptions);
1483 break;
1484
1485 case IP_PORTRANGE:
1486 error = soopt_to_kbuf(sopt, &optval, sizeof optval,
1487 sizeof optval);
1488 if (error)
1489 break;
1490
1491 switch (optval) {
1492 case IP_PORTRANGE_DEFAULT:
1493 inp->inp_flags &= ~(INP_LOWPORT);
1494 inp->inp_flags &= ~(INP_HIGHPORT);
1495 break;
1496
1497 case IP_PORTRANGE_HIGH:
1498 inp->inp_flags &= ~(INP_LOWPORT);
1499 inp->inp_flags |= INP_HIGHPORT;
1500 break;
1501
1502 case IP_PORTRANGE_LOW:
1503 inp->inp_flags &= ~(INP_HIGHPORT);
1504 inp->inp_flags |= INP_LOWPORT;
1505 break;
1506
1507 default:
1508 error = EINVAL;
1509 break;
1510 }
1511 break;
1512
1513 #if defined(IPSEC) || defined(FAST_IPSEC)
1514 case IP_IPSEC_POLICY:
1515 {
1516 caddr_t req;
1517 size_t len = 0;
1518 int priv;
1519 struct mbuf *m;
1520 int optname;
1521
1522 if ((error = soopt_getm(sopt, &m)) != 0) /* XXX */
1523 break;
1524 soopt_to_mbuf(sopt, m);
1525 priv = (sopt->sopt_td != NULL &&
1526 priv_check(sopt->sopt_td, PRIV_ROOT) != 0) ? 0 : 1;
1527 req = mtod(m, caddr_t);
1528 len = m->m_len;
1529 optname = sopt->sopt_name;
1530 error = ipsec4_set_policy(inp, optname, req, len, priv);
1531 m_freem(m);
1532 break;
1533 }
1534 #endif /*IPSEC*/
1535
1536 default:
1537 error = ENOPROTOOPT;
1538 break;
1539 }
1540 break;
1541
1542 case SOPT_GET:
1543 switch (sopt->sopt_name) {
1544 case IP_OPTIONS:
1545 case IP_RETOPTS:
1546 if (inp->inp_options)
1547 soopt_from_kbuf(sopt, mtod(inp->inp_options,
1548 char *),
1549 inp->inp_options->m_len);
1550 else
1551 sopt->sopt_valsize = 0;
1552 break;
1553
1554 case IP_TOS:
1555 case IP_TTL:
1556 case IP_MINTTL:
1557 case IP_RECVOPTS:
1558 case IP_RECVRETOPTS:
1559 case IP_RECVDSTADDR:
1560 case IP_RECVTTL:
1561 case IP_RECVIF:
1562 case IP_PORTRANGE:
1563 switch (sopt->sopt_name) {
1564
1565 case IP_TOS:
1566 optval = inp->inp_ip_tos;
1567 break;
1568
1569 case IP_TTL:
1570 optval = inp->inp_ip_ttl;
1571 break;
1572 case IP_MINTTL:
1573 optval = inp->inp_ip_minttl;
1574 break;
1575
1576 #define OPTBIT(bit) (inp->inp_flags & bit ? 1 : 0)
1577
1578 case IP_RECVOPTS:
1579 optval = OPTBIT(INP_RECVOPTS);
1580 break;
1581
1582 case IP_RECVRETOPTS:
1583 optval = OPTBIT(INP_RECVRETOPTS);
1584 break;
1585
1586 case IP_RECVDSTADDR:
1587 optval = OPTBIT(INP_RECVDSTADDR);
1588 break;
1589
1590 case IP_RECVTTL:
1591 optval = OPTBIT(INP_RECVTTL);
1592 break;
1593
1594 case IP_RECVIF:
1595 optval = OPTBIT(INP_RECVIF);
1596 break;
1597
1598 case IP_PORTRANGE:
1599 if (inp->inp_flags & INP_HIGHPORT)
1600 optval = IP_PORTRANGE_HIGH;
1601 else if (inp->inp_flags & INP_LOWPORT)
1602 optval = IP_PORTRANGE_LOW;
1603 else
1604 optval = 0;
1605 break;
1606 }
1607 soopt_from_kbuf(sopt, &optval, sizeof optval);
1608 break;
1609
1610 case IP_MULTICAST_IF:
1611 case IP_MULTICAST_VIF:
1612 case IP_MULTICAST_TTL:
1613 case IP_MULTICAST_LOOP:
1614 case IP_ADD_MEMBERSHIP:
1615 case IP_DROP_MEMBERSHIP:
1616 error = ip_getmoptions(sopt, inp->inp_moptions);
1617 break;
1618
1619 #if defined(IPSEC) || defined(FAST_IPSEC)
1620 case IP_IPSEC_POLICY:
1621 {
1622 struct mbuf *m = NULL;
1623 caddr_t req = NULL;
1624 size_t len = 0;
1625
1626 if (m != NULL) {
1627 req = mtod(m, caddr_t);
1628 len = m->m_len;
1629 }
1630 error = ipsec4_get_policy(so->so_pcb, req, len, &m);
1631 if (error == 0)
1632 error = soopt_from_mbuf(sopt, m); /* XXX */
1633 if (error == 0)
1634 m_freem(m);
1635 break;
1636 }
1637 #endif /*IPSEC*/
1638
1639 default:
1640 error = ENOPROTOOPT;
1641 break;
1642 }
1643 break;
1644 }
1645 done:
1646 lwkt_replymsg(&msg->lmsg, error);
1647 }
1648
1649 /*
1650 * Set up IP options in pcb for insertion in output packets.
1651 * Store in mbuf with pointer in pcbopt, adding pseudo-option
1652 * with destination address if source routed.
1653 */
1654 static int
1655 ip_pcbopts(int optname, struct mbuf **pcbopt, struct mbuf *m)
1656 {
1657 int cnt, optlen;
1658 u_char *cp;
1659 u_char opt;
1660
1661 /* turn off any old options */
1662 if (*pcbopt)
1663 m_free(*pcbopt);
1664 *pcbopt = NULL;
1665 if (m == NULL || m->m_len == 0) {
1666 /*
1667 * Only turning off any previous options.
1668 */
1669 if (m != NULL)
1670 m_free(m);
1671 return (0);
1672 }
1673
1674 if (m->m_len % sizeof(int32_t))
1675 goto bad;
1676 /*
1677 * IP first-hop destination address will be stored before
1678 * actual options; move other options back
1679 * and clear it when none present.
1680 */
1681 if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
1682 goto bad;
1683 cnt = m->m_len;
1684 m->m_len += sizeof(struct in_addr);
1685 cp = mtod(m, u_char *) + sizeof(struct in_addr);
1686 bcopy(mtod(m, caddr_t), cp, cnt);
1687 bzero(mtod(m, caddr_t), sizeof(struct in_addr));
1688
1689 for (; cnt > 0; cnt -= optlen, cp += optlen) {
1690 opt = cp[IPOPT_OPTVAL];
1691 if (opt == IPOPT_EOL)
1692 break;
1693 if (opt == IPOPT_NOP)
1694 optlen = 1;
1695 else {
1696 if (cnt < IPOPT_OLEN + sizeof *cp)
1697 goto bad;
1698 optlen = cp[IPOPT_OLEN];
1699 if (optlen < IPOPT_OLEN + sizeof *cp || optlen > cnt)
1700 goto bad;
1701 }
1702 switch (opt) {
1703
1704 default:
1705 break;
1706
1707 case IPOPT_LSRR:
1708 case IPOPT_SSRR:
1709 /*
1710 * user process specifies route as:
1711 * ->A->B->C->D
1712 * D must be our final destination (but we can't
1713 * check that since we may not have connected yet).
1714 * A is first hop destination, which doesn't appear in
1715 * actual IP option, but is stored before the options.
1716 */
1717 if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
1718 goto bad;
1719 m->m_len -= sizeof(struct in_addr);
1720 cnt -= sizeof(struct in_addr);
1721 optlen -= sizeof(struct in_addr);
1722 cp[IPOPT_OLEN] = optlen;
1723 /*
1724 * Move first hop before start of options.
1725 */
1726 bcopy(&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
1727 sizeof(struct in_addr));
1728 /*
1729 * Then copy rest of options back
1730 * to close up the deleted entry.
1731 */
1732 bcopy(&cp[IPOPT_OFFSET+1] + sizeof(struct in_addr),
1733 &cp[IPOPT_OFFSET+1],
1734 cnt - (IPOPT_MINOFF - 1));
1735 break;
1736 }
1737 }
1738 if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
1739 goto bad;
1740 *pcbopt = m;
1741 return (0);
1742
1743 bad:
1744 m_free(m);
1745 return (EINVAL);
1746 }
1747
1748 /*
1749 * XXX
1750 * The whole multicast option thing needs to be re-thought.
1751 * Several of these options are equally applicable to non-multicast
1752 * transmission, and one (IP_MULTICAST_TTL) totally duplicates a
1753 * standard option (IP_TTL).
1754 */
1755
1756 /*
1757 * following RFC1724 section 3.3, 0.0.0.0/8 is interpreted as interface index.
1758 */
1759 static struct ifnet *
1760 ip_multicast_if(struct in_addr *a, int *ifindexp)
1761 {
1762 int ifindex;
1763 struct ifnet *ifp;
1764
1765 if (ifindexp)
1766 *ifindexp = 0;
1767 if (ntohl(a->s_addr) >> 24 == 0) {
1768 ifindex = ntohl(a->s_addr) & 0xffffff;
1769 if (ifindex < 0 || if_index < ifindex)
1770 return NULL;
1771 ifp = ifindex2ifnet[ifindex];
1772 if (ifindexp)
1773 *ifindexp = ifindex;
1774 } else {
1775 ifp = INADDR_TO_IFP(a);
1776 }
1777 return ifp;
1778 }
1779
1780 /*
1781 * Set the IP multicast options in response to user setsockopt().
1782 */
1783 static int
1784 ip_setmoptions(struct sockopt *sopt, struct ip_moptions **imop)
1785 {
1786 int error = 0;
1787 int i;
1788 struct in_addr addr;
1789 struct ip_mreq mreq;
1790 struct ifnet *ifp;
1791 struct ip_moptions *imo = *imop;
1792 int ifindex;
1793
1794 if (imo == NULL) {
1795 /*
1796 * No multicast option buffer attached to the pcb;
1797 * allocate one and initialize to default values.
1798 */
1799 imo = kmalloc(sizeof *imo, M_IPMOPTS, M_WAITOK);
1800
1801 imo->imo_multicast_ifp = NULL;
1802 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1803 imo->imo_multicast_vif = -1;
1804 imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1805 imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
1806 imo->imo_num_memberships = 0;
1807 /* Assign imo to imop after all fields are setup */
1808 cpu_sfence();
1809 *imop = imo;
1810 }
1811 switch (sopt->sopt_name) {
1812 /* store an index number for the vif you wanna use in the send */
1813 case IP_MULTICAST_VIF:
1814 if (legal_vif_num == 0) {
1815 error = EOPNOTSUPP;
1816 break;
1817 }
1818 error = soopt_to_kbuf(sopt, &i, sizeof i, sizeof i);
1819 if (error)
1820 break;
1821 if (!legal_vif_num(i) && (i != -1)) {
1822 error = EINVAL;
1823 break;
1824 }
1825 imo->imo_multicast_vif = i;
1826 break;
1827
1828 case IP_MULTICAST_IF:
1829 /*
1830 * Select the interface for outgoing multicast packets.
1831 */
1832 error = soopt_to_kbuf(sopt, &addr, sizeof addr, sizeof addr);
1833 if (error)
1834 break;
1835
1836 /*
1837 * INADDR_ANY is used to remove a previous selection.
1838 * When no interface is selected, a default one is
1839 * chosen every time a multicast packet is sent.
1840 */
1841 if (addr.s_addr == INADDR_ANY) {
1842 imo->imo_multicast_ifp = NULL;
1843 break;
1844 }
1845 /*
1846 * The selected interface is identified by its local
1847 * IP address. Find the interface and confirm that
1848 * it supports multicasting.
1849 */
1850 crit_enter();
1851 ifp = ip_multicast_if(&addr, &ifindex);
1852 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1853 crit_exit();
1854 error = EADDRNOTAVAIL;
1855 break;
1856 }
1857 imo->imo_multicast_ifp = ifp;
1858 if (ifindex)
1859 imo->imo_multicast_addr = addr;
1860 else
1861 imo->imo_multicast_addr.s_addr = INADDR_ANY;
1862 crit_exit();
1863 break;
1864
1865 case IP_MULTICAST_TTL:
1866 /*
1867 * Set the IP time-to-live for outgoing multicast packets.
1868 * The original multicast API required a char argument,
1869 * which is inconsistent with the rest of the socket API.
1870 * We allow either a char or an int.
1871 */
1872 if (sopt->sopt_valsize == 1) {
1873 u_char ttl;
1874 error = soopt_to_kbuf(sopt, &ttl, 1, 1);
1875 if (error)
1876 break;
1877 imo->imo_multicast_ttl = ttl;
1878 } else {
1879 u_int ttl;
1880 error = soopt_to_kbuf(sopt, &ttl, sizeof ttl, sizeof ttl);
1881 if (error)
1882 break;
1883 if (ttl > 255)
1884 error = EINVAL;
1885 else
1886 imo->imo_multicast_ttl = ttl;
1887 }
1888 break;
1889
1890 case IP_MULTICAST_LOOP:
1891 /*
1892 * Set the loopback flag for outgoing multicast packets.
1893 * Must be zero or one. The original multicast API required a
1894 * char argument, which is inconsistent with the rest
1895 * of the socket API. We allow either a char or an int.
1896 */
1897 if (sopt->sopt_valsize == 1) {
1898 u_char loop;
1899
1900 error = soopt_to_kbuf(sopt, &loop, 1, 1);
1901 if (error)
1902 break;
1903 imo->imo_multicast_loop = !!loop;
1904 } else {
1905 u_int loop;
1906
1907 error = soopt_to_kbuf(sopt, &loop, sizeof loop,
1908 sizeof loop);
1909 if (error)
1910 break;
1911 imo->imo_multicast_loop = !!loop;
1912 }
1913 break;
1914
1915 case IP_ADD_MEMBERSHIP:
1916 /*
1917 * Add a multicast group membership.
1918 * Group must be a valid IP multicast address.
1919 */
1920 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
1921 if (error)
1922 break;
1923
1924 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
1925 error = EINVAL;
1926 break;
1927 }
1928 crit_enter();
1929 /*
1930 * If no interface address was provided, use the interface of
1931 * the route to the given multicast address.
1932 */
1933 if (mreq.imr_interface.s_addr == INADDR_ANY) {
1934 struct sockaddr_in dst;
1935 struct rtentry *rt;
1936
1937 bzero(&dst, sizeof(struct sockaddr_in));
1938 dst.sin_len = sizeof(struct sockaddr_in);
1939 dst.sin_family = AF_INET;
1940 dst.sin_addr = mreq.imr_multiaddr;
1941 rt = rtlookup((struct sockaddr *)&dst);
1942 if (rt == NULL) {
1943 error = EADDRNOTAVAIL;
1944 crit_exit();
1945 break;
1946 }
1947 --rt->rt_refcnt;
1948 ifp = rt->rt_ifp;
1949 } else {
1950 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
1951 }
1952
1953 /*
1954 * See if we found an interface, and confirm that it
1955 * supports multicast.
1956 */
1957 if (ifp == NULL || !(ifp->if_flags & IFF_MULTICAST)) {
1958 error = EADDRNOTAVAIL;
1959 crit_exit();
1960 break;
1961 }
1962 /*
1963 * See if the membership already exists or if all the
1964 * membership slots are full.
1965 */
1966 for (i = 0; i < imo->imo_num_memberships; ++i) {
1967 if (imo->imo_membership[i]->inm_ifp == ifp &&
1968 imo->imo_membership[i]->inm_addr.s_addr
1969 == mreq.imr_multiaddr.s_addr)
1970 break;
1971 }
1972 if (i < imo->imo_num_memberships) {
1973 error = EADDRINUSE;
1974 crit_exit();
1975 break;
1976 }
1977 if (i == IP_MAX_MEMBERSHIPS) {
1978 error = ETOOMANYREFS;
1979 crit_exit();
1980 break;
1981 }
1982 /*
1983 * Everything looks good; add a new record to the multicast
1984 * address list for the given interface.
1985 */
1986 if ((imo->imo_membership[i] =
1987 in_addmulti(&mreq.imr_multiaddr, ifp)) == NULL) {
1988 error = ENOBUFS;
1989 crit_exit();
1990 break;
1991 }
1992 ++imo->imo_num_memberships;
1993 crit_exit();
1994 break;
1995
1996 case IP_DROP_MEMBERSHIP:
1997 /*
1998 * Drop a multicast group membership.
1999 * Group must be a valid IP multicast address.
2000 */
2001 error = soopt_to_kbuf(sopt, &mreq, sizeof mreq, sizeof mreq);
2002 if (error)
2003 break;
2004
2005 if (!IN_MULTICAST(ntohl(mreq.imr_multiaddr.s_addr))) {
2006 error = EINVAL;
2007 break;
2008 }
2009
2010 crit_enter();
2011 /*
2012 * If an interface address was specified, get a pointer
2013 * to its ifnet structure.
2014 */
2015 if (mreq.imr_interface.s_addr == INADDR_ANY)
2016 ifp = NULL;
2017 else {
2018 ifp = ip_multicast_if(&mreq.imr_interface, NULL);
2019 if (ifp == NULL) {
2020 error = EADDRNOTAVAIL;
2021 crit_exit();
2022 break;
2023 }
2024 }
2025 /*
2026 * Find the membership in the membership array.
2027 */
2028 for (i = 0; i < imo->imo_num_memberships; ++i) {
2029 if ((ifp == NULL ||
2030 imo->imo_membership[i]->inm_ifp == ifp) &&
2031 imo->imo_membership[i]->inm_addr.s_addr ==
2032 mreq.imr_multiaddr.s_addr)
2033 break;
2034 }
2035 if (i == imo->imo_num_memberships) {
2036 error = EADDRNOTAVAIL;
2037 crit_exit();
2038 break;
2039 }
2040 /*
2041 * Give up the multicast address record to which the
2042 * membership points.
2043 */
2044 in_delmulti(imo->imo_membership[i]);
2045 /*
2046 * Remove the gap in the membership array.
2047 */
2048 for (++i; i < imo->imo_num_memberships; ++i)
2049 imo->imo_membership[i-1] = imo->imo_membership[i];
2050 --imo->imo_num_memberships;
2051 crit_exit();
2052 break;
2053
2054 default:
2055 error = EOPNOTSUPP;
2056 break;
2057 }
2058
2059 return (error);
2060 }
2061
2062 /*
2063 * Return the IP multicast options in response to user getsockopt().
2064 */
2065 static int
2066 ip_getmoptions(struct sockopt *sopt, struct ip_moptions *imo)
2067 {
2068 struct in_addr addr;
2069 struct in_ifaddr *ia;
2070 int error, optval;
2071 u_char coptval;
2072
2073 error = 0;
2074 switch (sopt->sopt_name) {
2075 case IP_MULTICAST_VIF:
2076 if (imo != NULL)
2077 optval = imo->imo_multicast_vif;
2078 else
2079 optval = -1;
2080 soopt_from_kbuf(sopt, &optval, sizeof optval);
2081 break;
2082
2083 case IP_MULTICAST_IF:
2084 if (imo == NULL || imo->imo_multicast_ifp == NULL)
2085 addr.s_addr = INADDR_ANY;
2086 else if (imo->imo_multicast_addr.s_addr) {
2087 /* return the value user has set */
2088 addr = imo->imo_multicast_addr;
2089 } else {
2090 ia = IFP_TO_IA(imo->imo_multicast_ifp);
2091 addr.s_addr = (ia == NULL) ? INADDR_ANY
2092 : IA_SIN(ia)->sin_addr.s_addr;
2093 }
2094 soopt_from_kbuf(sopt, &addr, sizeof addr);
2095 break;
2096
2097 case IP_MULTICAST_TTL:
2098 if (imo == NULL)
2099 optval = coptval = IP_DEFAULT_MULTICAST_TTL;
2100 else
2101 optval = coptval = imo->imo_multicast_ttl;
2102 if (sopt->sopt_valsize == 1)
2103 soopt_from_kbuf(sopt, &coptval, 1);
2104 else
2105 soopt_from_kbuf(sopt, &optval, sizeof optval);
2106 break;
2107
2108 case IP_MULTICAST_LOOP:
2109 if (imo == NULL)
2110 optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
2111 else
2112 optval = coptval = imo->imo_multicast_loop;
2113 if (sopt->sopt_valsize == 1)
2114 soopt_from_kbuf(sopt, &coptval, 1);
2115 else
2116 soopt_from_kbuf(sopt, &optval, sizeof optval);
2117 break;
2118
2119 default:
2120 error = ENOPROTOOPT;
2121 break;
2122 }
2123 return (error);
2124 }
2125
2126 /*
2127 * Discard the IP multicast options.
2128 */
2129 void
2130 ip_freemoptions(struct ip_moptions *imo)
2131 {
2132 int i;
2133
2134 if (imo != NULL) {
2135 for (i = 0; i < imo->imo_num_memberships; ++i)
2136 in_delmulti(imo->imo_membership[i]);
2137 kfree(imo, M_IPMOPTS);
2138 }
2139 }
2140
2141 /*
2142 * Routine called from ip_output() to loop back a copy of an IP multicast
2143 * packet to the input queue of a specified interface. Note that this
2144 * calls the output routine of the loopback "driver", but with an interface
2145 * pointer that might NOT be a loopback interface -- evil, but easier than
2146 * replicating that code here.
2147 */
2148 static void
2149 ip_mloopback(struct ifnet *ifp, struct mbuf *m, struct sockaddr_in *dst,
2150 int hlen)
2151 {
2152 struct ip *ip;
2153 struct mbuf *copym;
2154
2155 copym = m_copypacket(m, M_NOWAIT);
2156 if (copym != NULL && (copym->m_flags & M_EXT || copym->m_len < hlen))
2157 copym = m_pullup(copym, hlen);
2158 if (copym != NULL) {
2159 /*
2160 * if the checksum hasn't been computed, mark it as valid
2161 */
2162 if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
2163 in_delayed_cksum(copym);
2164 copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
2165 copym->m_pkthdr.csum_flags |=
2166 CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
2167 copym->m_pkthdr.csum_data = 0xffff;
2168 }
2169 /*
2170 * We don't bother to fragment if the IP length is greater
2171 * than the interface's MTU. Can this possibly matter?
2172 */
2173 ip = mtod(copym, struct ip *);
2174 ip->ip_len = htons(ip->ip_len);
2175 ip->ip_off = htons(ip->ip_off);
2176 ip->ip_sum = 0;
2177 if (ip->ip_vhl == IP_VHL_BORING) {
2178 ip->ip_sum = in_cksum_hdr(ip);
2179 } else {
2180 ip->ip_sum = in_cksum(copym, hlen);
2181 }
2182 /*
2183 * NB:
2184 * It's not clear whether there are any lingering
2185 * reentrancy problems in other areas which might
2186 * be exposed by using ip_input directly (in
2187 * particular, everything which modifies the packet
2188 * in-place). Yet another option is using the
2189 * protosw directly to deliver the looped back
2190 * packet. For the moment, we'll err on the side
2191 * of safety by using if_simloop().
2192 */
2193 #if 1 /* XXX */
2194 if (dst->sin_family != AF_INET) {
2195 kprintf("ip_mloopback: bad address family %d\n",
2196 dst->sin_family);
2197 dst->sin_family = AF_INET;
2198 }
2199 #endif
2200 if_simloop(ifp, copym, dst->sin_family, 0);
2201 }
2202 }
DragonFly BSD