1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1988, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include "opt_bootp.h"
33 #include "opt_inet.h"
34 #include "opt_ipstealth.h"
35 #include "opt_ipsec.h"
36 #include "opt_route.h"
37 #include "opt_rss.h"
38 #include "opt_sctp.h"
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/hhook.h>
43 #include <sys/mbuf.h>
44 #include <sys/malloc.h>
45 #include <sys/domain.h>
46 #include <sys/protosw.h>
47 #include <sys/socket.h>
48 #include <sys/time.h>
49 #include <sys/kernel.h>
50 #include <sys/lock.h>
51 #include <sys/rmlock.h>
52 #include <sys/rwlock.h>
53 #include <sys/sdt.h>
54 #include <sys/syslog.h>
55 #include <sys/sysctl.h>
56
57 #include <net/if.h>
58 #include <net/if_types.h>
59 #include <net/if_var.h>
60 #include <net/if_dl.h>
61 #include <net/if_private.h>
62 #include <net/pfil.h>
63 #include <net/route.h>
64 #include <net/route/nhop.h>
65 #include <net/netisr.h>
66 #include <net/rss_config.h>
67 #include <net/vnet.h>
68
69 #include <netinet/in.h>
70 #include <netinet/in_kdtrace.h>
71 #include <netinet/in_systm.h>
72 #include <netinet/in_var.h>
73 #include <netinet/ip.h>
74 #include <netinet/in_fib.h>
75 #include <netinet/in_pcb.h>
76 #include <netinet/ip_var.h>
77 #include <netinet/ip_encap.h>
78 #include <netinet/ip_fw.h>
79 #include <netinet/ip_icmp.h>
80 #include <netinet/igmp_var.h>
81 #include <netinet/ip_options.h>
82 #include <machine/in_cksum.h>
83 #include <netinet/ip_carp.h>
84 #include <netinet/in_rss.h>
85 #include <netinet/ip_mroute.h>
86 #ifdef SCTP
87 #include <netinet/sctp_var.h>
88 #endif
89
90 #include <netipsec/ipsec_support.h>
91
92 #include <sys/socketvar.h>
93
94 #include <security/mac/mac_framework.h>
95
96 #ifdef CTASSERT
97 CTASSERT(sizeof(struct ip) == 20);
98 #endif
99
100 /* IP reassembly functions are defined in ip_reass.c. */
101 extern void ipreass_init(void);
102 extern void ipreass_vnet_init(void);
103 #ifdef VIMAGE
104 extern void ipreass_destroy(void);
105 #endif
106
107 VNET_DEFINE(int, rsvp_on);
108
109 VNET_DEFINE(int, ipforwarding);
110 SYSCTL_INT(_net_inet_ip, IPCTL_FORWARDING, forwarding, CTLFLAG_VNET | CTLFLAG_RW,
111 &VNET_NAME(ipforwarding), 0,
112 "Enable IP forwarding between interfaces");
113
114 /*
115 * Respond with an ICMP host redirect when we forward a packet out of
116 * the same interface on which it was received. See RFC 792.
117 */
118 VNET_DEFINE(int, ipsendredirects) = 1;
119 SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect, CTLFLAG_VNET | CTLFLAG_RW,
120 &VNET_NAME(ipsendredirects), 0,
121 "Enable sending IP redirects");
122
123 VNET_DEFINE_STATIC(bool, ip_strong_es) = false;
124 #define V_ip_strong_es VNET(ip_strong_es)
125 SYSCTL_BOOL(_net_inet_ip, OID_AUTO, rfc1122_strong_es,
126 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip_strong_es), false,
127 "Packet's IP destination address must match address on arrival interface");
128
129 VNET_DEFINE_STATIC(bool, ip_sav) = true;
130 #define V_ip_sav VNET(ip_sav)
131 SYSCTL_BOOL(_net_inet_ip, OID_AUTO, source_address_validation,
132 CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip_sav), true,
133 "Drop incoming packets with source address that is a local address");
134
135 /* Packet filter hooks */
136 VNET_DEFINE(pfil_head_t, inet_pfil_head);
137 VNET_DEFINE(pfil_head_t, inet_local_pfil_head);
138
139 static struct netisr_handler ip_nh = {
140 .nh_name = "ip",
141 .nh_handler = ip_input,
142 .nh_proto = NETISR_IP,
143 #ifdef RSS
144 .nh_m2cpuid = rss_soft_m2cpuid_v4,
145 .nh_policy = NETISR_POLICY_CPU,
146 .nh_dispatch = NETISR_DISPATCH_HYBRID,
147 #else
148 .nh_policy = NETISR_POLICY_FLOW,
149 #endif
150 };
151
152 #ifdef RSS
153 /*
154 * Directly dispatched frames are currently assumed
155 * to have a flowid already calculated.
156 *
157 * It should likely have something that assert it
158 * actually has valid flow details.
159 */
160 static struct netisr_handler ip_direct_nh = {
161 .nh_name = "ip_direct",
162 .nh_handler = ip_direct_input,
163 .nh_proto = NETISR_IP_DIRECT,
164 .nh_m2cpuid = rss_soft_m2cpuid_v4,
165 .nh_policy = NETISR_POLICY_CPU,
166 .nh_dispatch = NETISR_DISPATCH_HYBRID,
167 };
168 #endif
169
170 ipproto_input_t *ip_protox[IPPROTO_MAX] = {
171 [0 ... IPPROTO_MAX - 1] = rip_input };
172 ipproto_ctlinput_t *ip_ctlprotox[IPPROTO_MAX] = {
173 [0 ... IPPROTO_MAX - 1] = rip_ctlinput };
174
175 VNET_DEFINE(struct in_ifaddrhead, in_ifaddrhead); /* first inet address */
176 VNET_DEFINE(struct in_ifaddrhashhead *, in_ifaddrhashtbl); /* inet addr hash table */
177 VNET_DEFINE(u_long, in_ifaddrhmask); /* mask for hash table */
178
179 /* Make sure it is safe to use hashinit(9) on CK_LIST. */
180 CTASSERT(sizeof(struct in_ifaddrhashhead) == sizeof(LIST_HEAD(, in_addr)));
181
182 #ifdef IPCTL_DEFMTU
183 SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW,
184 &ip_mtu, 0, "Default MTU");
185 #endif
186
187 #ifdef IPSTEALTH
188 VNET_DEFINE(int, ipstealth);
189 SYSCTL_INT(_net_inet_ip, OID_AUTO, stealth, CTLFLAG_VNET | CTLFLAG_RW,
190 &VNET_NAME(ipstealth), 0,
191 "IP stealth mode, no TTL decrementation on forwarding");
192 #endif
193
194 /*
195 * IP statistics are stored in the "array" of counter(9)s.
196 */
197 VNET_PCPUSTAT_DEFINE(struct ipstat, ipstat);
198 VNET_PCPUSTAT_SYSINIT(ipstat);
199 SYSCTL_VNET_PCPUSTAT(_net_inet_ip, IPCTL_STATS, stats, struct ipstat, ipstat,
200 "IP statistics (struct ipstat, netinet/ip_var.h)");
201
202 #ifdef VIMAGE
203 VNET_PCPUSTAT_SYSUNINIT(ipstat);
204 #endif /* VIMAGE */
205
206 /*
207 * Kernel module interface for updating ipstat. The argument is an index
208 * into ipstat treated as an array.
209 */
210 void
kmod_ipstat_inc(int statnum)211 kmod_ipstat_inc(int statnum)
212 {
213
214 counter_u64_add(VNET(ipstat)[statnum], 1);
215 }
216
217 void
kmod_ipstat_dec(int statnum)218 kmod_ipstat_dec(int statnum)
219 {
220
221 counter_u64_add(VNET(ipstat)[statnum], -1);
222 }
223
224 static int
sysctl_netinet_intr_queue_maxlen(SYSCTL_HANDLER_ARGS)225 sysctl_netinet_intr_queue_maxlen(SYSCTL_HANDLER_ARGS)
226 {
227 int error, qlimit;
228
229 netisr_getqlimit(&ip_nh, &qlimit);
230 error = sysctl_handle_int(oidp, &qlimit, 0, req);
231 if (error || !req->newptr)
232 return (error);
233 if (qlimit < 1)
234 return (EINVAL);
235 return (netisr_setqlimit(&ip_nh, qlimit));
236 }
237 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen,
238 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0,
239 sysctl_netinet_intr_queue_maxlen, "I",
240 "Maximum size of the IP input queue");
241
242 static int
sysctl_netinet_intr_queue_drops(SYSCTL_HANDLER_ARGS)243 sysctl_netinet_intr_queue_drops(SYSCTL_HANDLER_ARGS)
244 {
245 u_int64_t qdrops_long;
246 int error, qdrops;
247
248 netisr_getqdrops(&ip_nh, &qdrops_long);
249 qdrops = qdrops_long;
250 error = sysctl_handle_int(oidp, &qdrops, 0, req);
251 if (error || !req->newptr)
252 return (error);
253 if (qdrops != 0)
254 return (EINVAL);
255 netisr_clearqdrops(&ip_nh);
256 return (0);
257 }
258
259 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops,
260 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
261 0, 0, sysctl_netinet_intr_queue_drops, "I",
262 "Number of packets dropped from the IP input queue");
263
264 #ifdef RSS
265 static int
sysctl_netinet_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS)266 sysctl_netinet_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS)
267 {
268 int error, qlimit;
269
270 netisr_getqlimit(&ip_direct_nh, &qlimit);
271 error = sysctl_handle_int(oidp, &qlimit, 0, req);
272 if (error || !req->newptr)
273 return (error);
274 if (qlimit < 1)
275 return (EINVAL);
276 return (netisr_setqlimit(&ip_direct_nh, qlimit));
277 }
278 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRDQMAXLEN, intr_direct_queue_maxlen,
279 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
280 0, 0, sysctl_netinet_intr_direct_queue_maxlen,
281 "I", "Maximum size of the IP direct input queue");
282
283 static int
sysctl_netinet_intr_direct_queue_drops(SYSCTL_HANDLER_ARGS)284 sysctl_netinet_intr_direct_queue_drops(SYSCTL_HANDLER_ARGS)
285 {
286 u_int64_t qdrops_long;
287 int error, qdrops;
288
289 netisr_getqdrops(&ip_direct_nh, &qdrops_long);
290 qdrops = qdrops_long;
291 error = sysctl_handle_int(oidp, &qdrops, 0, req);
292 if (error || !req->newptr)
293 return (error);
294 if (qdrops != 0)
295 return (EINVAL);
296 netisr_clearqdrops(&ip_direct_nh);
297 return (0);
298 }
299
300 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRDQDROPS, intr_direct_queue_drops,
301 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0,
302 sysctl_netinet_intr_direct_queue_drops, "I",
303 "Number of packets dropped from the IP direct input queue");
304 #endif /* RSS */
305
306 /*
307 * IP initialization: fill in IP protocol switch table.
308 * All protocols not implemented in kernel go to raw IP protocol handler.
309 */
310 static void
ip_vnet_init(void * arg __unused)311 ip_vnet_init(void *arg __unused)
312 {
313 struct pfil_head_args args;
314
315 CK_STAILQ_INIT(&V_in_ifaddrhead);
316 V_in_ifaddrhashtbl = hashinit(INADDR_NHASH, M_IFADDR, &V_in_ifaddrhmask);
317
318 /* Initialize IP reassembly queue. */
319 ipreass_vnet_init();
320
321 /* Initialize packet filter hooks. */
322 args.pa_version = PFIL_VERSION;
323 args.pa_flags = PFIL_IN | PFIL_OUT;
324 args.pa_type = PFIL_TYPE_IP4;
325 args.pa_headname = PFIL_INET_NAME;
326 V_inet_pfil_head = pfil_head_register(&args);
327
328 args.pa_flags = PFIL_OUT;
329 args.pa_headname = PFIL_INET_LOCAL_NAME;
330 V_inet_local_pfil_head = pfil_head_register(&args);
331
332 if (hhook_head_register(HHOOK_TYPE_IPSEC_IN, AF_INET,
333 &V_ipsec_hhh_in[HHOOK_IPSEC_INET],
334 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0)
335 printf("%s: WARNING: unable to register input helper hook\n",
336 __func__);
337 if (hhook_head_register(HHOOK_TYPE_IPSEC_OUT, AF_INET,
338 &V_ipsec_hhh_out[HHOOK_IPSEC_INET],
339 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0)
340 printf("%s: WARNING: unable to register output helper hook\n",
341 __func__);
342
343 #ifdef VIMAGE
344 netisr_register_vnet(&ip_nh);
345 #ifdef RSS
346 netisr_register_vnet(&ip_direct_nh);
347 #endif
348 #endif
349 }
350 VNET_SYSINIT(ip_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
351 ip_vnet_init, NULL);
352
353 static void
ip_init(const void * unused __unused)354 ip_init(const void *unused __unused)
355 {
356 struct ifnet *ifp;
357
358 ipreass_init();
359
360 /*
361 * Register statically compiled protocols, that are unlikely to
362 * ever become dynamic.
363 */
364 IPPROTO_REGISTER(IPPROTO_ICMP, icmp_input, NULL);
365 IPPROTO_REGISTER(IPPROTO_IGMP, igmp_input, NULL);
366 IPPROTO_REGISTER(IPPROTO_RSVP, rsvp_input, NULL);
367 IPPROTO_REGISTER(IPPROTO_IPV4, encap4_input, NULL);
368 IPPROTO_REGISTER(IPPROTO_MOBILE, encap4_input, NULL);
369 IPPROTO_REGISTER(IPPROTO_ETHERIP, encap4_input, NULL);
370 IPPROTO_REGISTER(IPPROTO_GRE, encap4_input, NULL);
371 IPPROTO_REGISTER(IPPROTO_IPV6, encap4_input, NULL);
372 IPPROTO_REGISTER(IPPROTO_PIM, encap4_input, NULL);
373 #ifdef SCTP /* XXX: has a loadable & static version */
374 IPPROTO_REGISTER(IPPROTO_SCTP, sctp_input, sctp_ctlinput);
375 #endif
376
377 netisr_register(&ip_nh);
378 #ifdef RSS
379 netisr_register(&ip_direct_nh);
380 #endif
381 /*
382 * XXXGL: we use SYSINIT() here, but go over V_ifnet. It was the same
383 * way before dom_ifattach removal. This worked because when any
384 * non-default vnet is created, there are no interfaces inside.
385 * Eventually this needs to be fixed.
386 */
387 CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link)
388 in_ifattach(NULL, ifp);
389 }
390 SYSINIT(ip_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip_init, NULL);
391
392 #ifdef VIMAGE
393 static void
ip_destroy(void * unused __unused)394 ip_destroy(void *unused __unused)
395 {
396 int error;
397
398 #ifdef RSS
399 netisr_unregister_vnet(&ip_direct_nh);
400 #endif
401 netisr_unregister_vnet(&ip_nh);
402
403 pfil_head_unregister(V_inet_pfil_head);
404 error = hhook_head_deregister(V_ipsec_hhh_in[HHOOK_IPSEC_INET]);
405 if (error != 0) {
406 printf("%s: WARNING: unable to deregister input helper hook "
407 "type HHOOK_TYPE_IPSEC_IN, id HHOOK_IPSEC_INET: "
408 "error %d returned\n", __func__, error);
409 }
410 error = hhook_head_deregister(V_ipsec_hhh_out[HHOOK_IPSEC_INET]);
411 if (error != 0) {
412 printf("%s: WARNING: unable to deregister output helper hook "
413 "type HHOOK_TYPE_IPSEC_OUT, id HHOOK_IPSEC_INET: "
414 "error %d returned\n", __func__, error);
415 }
416
417 /* Remove the IPv4 addresses from all interfaces. */
418 in_ifscrub_all();
419
420 /* Make sure the IPv4 routes are gone as well. */
421 rib_flush_routes_family(AF_INET);
422
423 /* Destroy IP reassembly queue. */
424 ipreass_destroy();
425
426 /* Cleanup in_ifaddr hash table; should be empty. */
427 hashdestroy(V_in_ifaddrhashtbl, M_IFADDR, V_in_ifaddrhmask);
428 }
429
430 VNET_SYSUNINIT(ip, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip_destroy, NULL);
431 #endif
432
433 #ifdef RSS
434 /*
435 * IP direct input routine.
436 *
437 * This is called when reinjecting completed fragments where
438 * all of the previous checking and book-keeping has been done.
439 */
440 void
ip_direct_input(struct mbuf * m)441 ip_direct_input(struct mbuf *m)
442 {
443 struct ip *ip;
444 int hlen;
445
446 ip = mtod(m, struct ip *);
447 hlen = ip->ip_hl << 2;
448
449 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
450 if (IPSEC_ENABLED(ipv4)) {
451 if (IPSEC_INPUT(ipv4, m, hlen, ip->ip_p) != 0)
452 return;
453 }
454 #endif /* IPSEC */
455 IPSTAT_INC(ips_delivered);
456 ip_protox[ip->ip_p](&m, &hlen, ip->ip_p);
457 }
458 #endif
459
460 /*
461 * Ip input routine. Checksum and byte swap header. If fragmented
462 * try to reassemble. Process options. Pass to next level.
463 */
464 void
ip_input(struct mbuf * m)465 ip_input(struct mbuf *m)
466 {
467 struct ip *ip = NULL;
468 struct in_ifaddr *ia = NULL;
469 struct ifaddr *ifa;
470 struct ifnet *ifp;
471 int hlen = 0;
472 uint16_t sum, ip_len;
473 int dchg = 0; /* dest changed after fw */
474 struct in_addr odst; /* original dst address */
475 bool strong_es;
476
477 M_ASSERTPKTHDR(m);
478 NET_EPOCH_ASSERT();
479
480 if (m->m_flags & M_FASTFWD_OURS) {
481 m->m_flags &= ~M_FASTFWD_OURS;
482 /* Set up some basics that will be used later. */
483 ip = mtod(m, struct ip *);
484 hlen = ip->ip_hl << 2;
485 ip_len = ntohs(ip->ip_len);
486 goto ours;
487 }
488
489 IPSTAT_INC(ips_total);
490
491 if (__predict_false(m->m_pkthdr.len < sizeof(struct ip)))
492 goto tooshort;
493
494 if (m->m_len < sizeof(struct ip)) {
495 m = m_pullup(m, sizeof(struct ip));
496 if (__predict_false(m == NULL)) {
497 IPSTAT_INC(ips_toosmall);
498 return;
499 }
500 }
501 ip = mtod(m, struct ip *);
502
503 if (__predict_false(ip->ip_v != IPVERSION)) {
504 IPSTAT_INC(ips_badvers);
505 goto bad;
506 }
507
508 hlen = ip->ip_hl << 2;
509 if (__predict_false(hlen < sizeof(struct ip))) { /* minimum header length */
510 IPSTAT_INC(ips_badhlen);
511 goto bad;
512 }
513 if (hlen > m->m_len) {
514 m = m_pullup(m, hlen);
515 if (__predict_false(m == NULL)) {
516 IPSTAT_INC(ips_badhlen);
517 return;
518 }
519 ip = mtod(m, struct ip *);
520 }
521
522 IP_PROBE(receive, NULL, NULL, ip, m->m_pkthdr.rcvif, ip, NULL);
523
524 /* IN_LOOPBACK must not appear on the wire - RFC1122 */
525 ifp = m->m_pkthdr.rcvif;
526 if (IN_LOOPBACK(ntohl(ip->ip_dst.s_addr)) ||
527 IN_LOOPBACK(ntohl(ip->ip_src.s_addr))) {
528 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
529 IPSTAT_INC(ips_badaddr);
530 goto bad;
531 }
532 }
533
534 if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) {
535 sum = !(m->m_pkthdr.csum_flags & CSUM_IP_VALID);
536 } else if (m->m_pkthdr.csum_flags & CSUM_IP) {
537 /*
538 * Packet from local host that offloaded checksum computation.
539 * Checksum not required since the packet wasn't on the wire.
540 */
541 sum = 0;
542 } else {
543 if (hlen == sizeof(struct ip)) {
544 sum = in_cksum_hdr(ip);
545 } else {
546 sum = in_cksum(m, hlen);
547 }
548 }
549 if (__predict_false(sum)) {
550 IPSTAT_INC(ips_badsum);
551 goto bad;
552 }
553
554 ip_len = ntohs(ip->ip_len);
555 if (__predict_false(ip_len < hlen)) {
556 IPSTAT_INC(ips_badlen);
557 goto bad;
558 }
559
560 /*
561 * Check that the amount of data in the buffers
562 * is as at least much as the IP header would have us expect.
563 * Trim mbufs if longer than we expect.
564 * Drop packet if shorter than we expect.
565 */
566 if (__predict_false(m->m_pkthdr.len < ip_len)) {
567 tooshort:
568 IPSTAT_INC(ips_tooshort);
569 goto bad;
570 }
571 if (m->m_pkthdr.len > ip_len) {
572 if (m->m_len == m->m_pkthdr.len) {
573 m->m_len = ip_len;
574 m->m_pkthdr.len = ip_len;
575 } else
576 m_adj(m, ip_len - m->m_pkthdr.len);
577 }
578
579 /*
580 * Try to forward the packet, but if we fail continue.
581 * ip_tryforward() may generate redirects these days.
582 * XXX the logic below falling through to normal processing
583 * if redirects are required should be revisited as well.
584 * ip_tryforward() does inbound and outbound packet firewall
585 * processing. If firewall has decided that destination becomes
586 * our local address, it sets M_FASTFWD_OURS flag. In this
587 * case skip another inbound firewall processing and update
588 * ip pointer.
589 */
590 if (V_ipforwarding != 0
591 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
592 && (!IPSEC_ENABLED(ipv4) ||
593 IPSEC_CAPS(ipv4, m, IPSEC_CAP_OPERABLE) == 0)
594 #endif
595 ) {
596 /*
597 * ip_dooptions() was run so we can ignore the source route (or
598 * any IP options case) case for redirects in ip_tryforward().
599 */
600 if ((m = ip_tryforward(m)) == NULL)
601 return;
602 if (m->m_flags & M_FASTFWD_OURS) {
603 m->m_flags &= ~M_FASTFWD_OURS;
604 ip = mtod(m, struct ip *);
605 goto ours;
606 }
607 }
608
609 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
610 /*
611 * Bypass packet filtering for packets previously handled by IPsec.
612 */
613 if (IPSEC_ENABLED(ipv4) &&
614 IPSEC_CAPS(ipv4, m, IPSEC_CAP_BYPASS_FILTER) != 0)
615 goto passin;
616 #endif
617
618 /*
619 * Run through list of hooks for input packets.
620 *
621 * NB: Beware of the destination address changing (e.g.
622 * by NAT rewriting). When this happens, tell
623 * ip_forward to do the right thing.
624 */
625
626 /* Jump over all PFIL processing if hooks are not active. */
627 if (!PFIL_HOOKED_IN(V_inet_pfil_head))
628 goto passin;
629
630 odst = ip->ip_dst;
631 if (pfil_mbuf_in(V_inet_pfil_head, &m, ifp, NULL) !=
632 PFIL_PASS)
633 return;
634
635 ip = mtod(m, struct ip *);
636 dchg = (odst.s_addr != ip->ip_dst.s_addr);
637
638 if (m->m_flags & M_FASTFWD_OURS) {
639 m->m_flags &= ~M_FASTFWD_OURS;
640 goto ours;
641 }
642 if (m->m_flags & M_IP_NEXTHOP) {
643 if (m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) {
644 /*
645 * Directly ship the packet on. This allows
646 * forwarding packets originally destined to us
647 * to some other directly connected host.
648 */
649 ip_forward(m, 1);
650 return;
651 }
652 }
653 passin:
654 /*
655 * The unspecified address can appear only as a src address - RFC1122.
656 *
657 * The check is deferred to here to give firewalls a chance to block
658 * (and log) such packets. ip_tryforward() will not process such
659 * packets.
660 */
661 if (__predict_false(ntohl(ip->ip_dst.s_addr) == INADDR_ANY)) {
662 IPSTAT_INC(ips_badaddr);
663 goto bad;
664 }
665
666 /*
667 * Process options and, if not destined for us,
668 * ship it on. ip_dooptions returns 1 when an
669 * error was detected (causing an icmp message
670 * to be sent and the original packet to be freed).
671 */
672 if (hlen > sizeof (struct ip) && ip_dooptions(m, 0))
673 return;
674
675 /* greedy RSVP, snatches any PATH packet of the RSVP protocol and no
676 * matter if it is destined to another node, or whether it is
677 * a multicast one, RSVP wants it! and prevents it from being forwarded
678 * anywhere else. Also checks if the rsvp daemon is running before
679 * grabbing the packet.
680 */
681 if (ip->ip_p == IPPROTO_RSVP && V_rsvp_on)
682 goto ours;
683
684 /*
685 * Check our list of addresses, to see if the packet is for us.
686 * If we don't have any addresses, assume any unicast packet
687 * we receive might be for us (and let the upper layers deal
688 * with it).
689 */
690 if (CK_STAILQ_EMPTY(&V_in_ifaddrhead) &&
691 (m->m_flags & (M_MCAST|M_BCAST)) == 0)
692 goto ours;
693
694 /*
695 * Enable a consistency check between the destination address
696 * and the arrival interface for a unicast packet (the RFC 1122
697 * strong ES model) with a list of additional predicates:
698 * - if IP forwarding is disabled
699 * - the packet is not locally generated
700 * - the packet is not subject to 'ipfw fwd'
701 * - Interface is not running CARP. If the packet got here, we already
702 * checked it with carp_iamatch() and carp_forus().
703 */
704 strong_es = V_ip_strong_es && (V_ipforwarding == 0) &&
705 ((ifp->if_flags & IFF_LOOPBACK) == 0) &&
706 ifp->if_carp == NULL && (dchg == 0);
707
708 /*
709 * Check for exact addresses in the hash bucket.
710 */
711 CK_LIST_FOREACH(ia, INADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
712 if (IA_SIN(ia)->sin_addr.s_addr != ip->ip_dst.s_addr)
713 continue;
714
715 /*
716 * net.inet.ip.rfc1122_strong_es: the address matches, verify
717 * that the packet arrived via the correct interface.
718 */
719 if (__predict_false(strong_es && ia->ia_ifp != ifp)) {
720 IPSTAT_INC(ips_badaddr);
721 goto bad;
722 }
723
724 /*
725 * net.inet.ip.source_address_validation: drop incoming
726 * packets that pretend to be ours.
727 */
728 if (V_ip_sav && !(ifp->if_flags & IFF_LOOPBACK) &&
729 __predict_false(in_localip_fib(ip->ip_src, ifp->if_fib))) {
730 IPSTAT_INC(ips_badaddr);
731 goto bad;
732 }
733
734 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
735 counter_u64_add(ia->ia_ifa.ifa_ibytes, m->m_pkthdr.len);
736 goto ours;
737 }
738
739 /*
740 * Check for broadcast addresses.
741 *
742 * Only accept broadcast packets that arrive via the matching
743 * interface. Reception of forwarded directed broadcasts would
744 * be handled via ip_forward() and ether_output() with the loopback
745 * into the stack for SIMPLEX interfaces handled by ether_output().
746 */
747 if (ifp->if_flags & IFF_BROADCAST) {
748 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
749 if (ifa->ifa_addr->sa_family != AF_INET)
750 continue;
751 ia = ifatoia(ifa);
752 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr ==
753 ip->ip_dst.s_addr) {
754 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
755 counter_u64_add(ia->ia_ifa.ifa_ibytes,
756 m->m_pkthdr.len);
757 goto ours;
758 }
759 #ifdef BOOTP_COMPAT
760 if (IA_SIN(ia)->sin_addr.s_addr == INADDR_ANY) {
761 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
762 counter_u64_add(ia->ia_ifa.ifa_ibytes,
763 m->m_pkthdr.len);
764 goto ours;
765 }
766 #endif
767 }
768 ia = NULL;
769 }
770 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
771 /*
772 * RFC 3927 2.7: Do not forward multicast packets from
773 * IN_LINKLOCAL.
774 */
775 if (V_ip_mrouting_enabled &&
776 !IN_LINKLOCAL(ntohl(ip->ip_src.s_addr))) {
777 /*
778 * If we are acting as a multicast router, all
779 * incoming multicast packets are passed to the
780 * kernel-level multicast forwarding function.
781 * The packet is returned (relatively) intact; if
782 * ip_mforward() returns a non-zero value, the packet
783 * must be discarded, else it may be accepted below.
784 */
785 if (ip_mforward && ip_mforward(ip, ifp, m, 0) != 0) {
786 IPSTAT_INC(ips_cantforward);
787 m_freem(m);
788 return;
789 }
790
791 /*
792 * The process-level routing daemon needs to receive
793 * all multicast IGMP packets, whether or not this
794 * host belongs to their destination groups.
795 */
796 if (ip->ip_p == IPPROTO_IGMP) {
797 goto ours;
798 }
799 IPSTAT_INC(ips_forward);
800 }
801 /*
802 * Assume the packet is for us, to avoid prematurely taking
803 * a lock on the in_multi hash. Protocols must perform
804 * their own filtering and update statistics accordingly.
805 */
806 goto ours;
807 }
808 if (in_broadcast(ip->ip_dst))
809 goto ours;
810 /* RFC 3927 2.7: Do not forward packets to or from IN_LINKLOCAL. */
811 if (IN_LINKLOCAL(ntohl(ip->ip_dst.s_addr)) ||
812 IN_LINKLOCAL(ntohl(ip->ip_src.s_addr))) {
813 IPSTAT_INC(ips_cantforward);
814 m_freem(m);
815 return;
816 }
817
818 /*
819 * Not for us; forward if possible and desirable.
820 */
821 if (V_ipforwarding == 0) {
822 IPSTAT_INC(ips_cantforward);
823 m_freem(m);
824 } else {
825 ip_forward(m, dchg);
826 }
827 return;
828
829 ours:
830 #ifdef IPSTEALTH
831 /*
832 * IPSTEALTH: Process non-routing options only
833 * if the packet is destined for us.
834 */
835 if (V_ipstealth && hlen > sizeof (struct ip) && ip_dooptions(m, 1))
836 return;
837 #endif /* IPSTEALTH */
838
839 /*
840 * We are going to ship the packet to the local protocol stack. Call the
841 * filter again for this 'output' action, allowing redirect-like rules
842 * to adjust the source address.
843 */
844 if (PFIL_HOOKED_OUT(V_inet_local_pfil_head)) {
845 if (pfil_mbuf_out(V_inet_local_pfil_head, &m, V_loif, NULL) !=
846 PFIL_PASS)
847 return;
848 ip = mtod(m, struct ip *);
849 }
850
851 /*
852 * Attempt reassembly; if it succeeds, proceed.
853 * ip_reass() will return a different mbuf.
854 */
855 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) {
856 /* XXXGL: shouldn't we save & set m_flags? */
857 m = ip_reass(m);
858 if (m == NULL)
859 return;
860 ip = mtod(m, struct ip *);
861 /* Get the header length of the reassembled packet */
862 hlen = ip->ip_hl << 2;
863 }
864
865 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
866 if (IPSEC_ENABLED(ipv4)) {
867 if (IPSEC_INPUT(ipv4, m, hlen, ip->ip_p) != 0)
868 return;
869 }
870 #endif /* IPSEC */
871
872 /*
873 * Switch out to protocol's input routine.
874 */
875 IPSTAT_INC(ips_delivered);
876
877 ip_protox[ip->ip_p](&m, &hlen, ip->ip_p);
878 return;
879 bad:
880 m_freem(m);
881 }
882
883 int
ipproto_register(uint8_t proto,ipproto_input_t input,ipproto_ctlinput_t ctl)884 ipproto_register(uint8_t proto, ipproto_input_t input, ipproto_ctlinput_t ctl)
885 {
886
887 MPASS(proto > 0);
888
889 /*
890 * The protocol slot must not be occupied by another protocol
891 * already. An index pointing to rip_input() is unused.
892 */
893 if (ip_protox[proto] == rip_input) {
894 ip_protox[proto] = input;
895 ip_ctlprotox[proto] = ctl;
896 return (0);
897 } else
898 return (EEXIST);
899 }
900
901 int
ipproto_unregister(uint8_t proto)902 ipproto_unregister(uint8_t proto)
903 {
904
905 MPASS(proto > 0);
906
907 if (ip_protox[proto] != rip_input) {
908 ip_protox[proto] = rip_input;
909 ip_ctlprotox[proto] = rip_ctlinput;
910 return (0);
911 } else
912 return (ENOENT);
913 }
914
915 /*
916 * Forward a packet. If some error occurs return the sender
917 * an icmp packet. Note we can't always generate a meaningful
918 * icmp message because icmp doesn't have a large enough repertoire
919 * of codes and types.
920 *
921 * If not forwarding, just drop the packet. This could be confusing
922 * if ipforwarding was zero but some routing protocol was advancing
923 * us as a gateway to somewhere. However, we must let the routing
924 * protocol deal with that.
925 *
926 * The srcrt parameter indicates whether the packet is being forwarded
927 * via a source route.
928 */
929 void
ip_forward(struct mbuf * m,int srcrt)930 ip_forward(struct mbuf *m, int srcrt)
931 {
932 struct ip *ip = mtod(m, struct ip *);
933 struct in_ifaddr *ia;
934 struct mbuf *mcopy;
935 struct sockaddr_in *sin;
936 struct in_addr dest;
937 struct route ro;
938 uint32_t flowid;
939 int error, type = 0, code = 0, mtu = 0;
940
941 NET_EPOCH_ASSERT();
942
943 if (m->m_flags & (M_BCAST|M_MCAST) || !in_canforward(ip->ip_dst)) {
944 IPSTAT_INC(ips_cantforward);
945 m_freem(m);
946 return;
947 }
948 if (
949 #ifdef IPSTEALTH
950 V_ipstealth == 0 &&
951 #endif
952 ip->ip_ttl <= IPTTLDEC) {
953 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, 0, 0);
954 return;
955 }
956
957 bzero(&ro, sizeof(ro));
958 sin = (struct sockaddr_in *)&ro.ro_dst;
959 sin->sin_family = AF_INET;
960 sin->sin_len = sizeof(*sin);
961 sin->sin_addr = ip->ip_dst;
962 flowid = m->m_pkthdr.flowid;
963 ro.ro_nh = fib4_lookup(M_GETFIB(m), ip->ip_dst, 0, NHR_REF, flowid);
964 if (ro.ro_nh != NULL) {
965 if (ro.ro_nh->nh_flags & (NHF_BLACKHOLE | NHF_BROADCAST)) {
966 IPSTAT_INC(ips_cantforward);
967 m_freem(m);
968 NH_FREE(ro.ro_nh);
969 return;
970 }
971 if (ro.ro_nh->nh_flags & NHF_REJECT) {
972 IPSTAT_INC(ips_cantforward);
973 NH_FREE(ro.ro_nh);
974 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
975 return;
976 }
977 ia = ifatoia(ro.ro_nh->nh_ifa);
978 } else
979 ia = NULL;
980 /*
981 * Save the IP header and at most 8 bytes of the payload,
982 * in case we need to generate an ICMP message to the src.
983 *
984 * XXX this can be optimized a lot by saving the data in a local
985 * buffer on the stack (72 bytes at most), and only allocating the
986 * mbuf if really necessary. The vast majority of the packets
987 * are forwarded without having to send an ICMP back (either
988 * because unnecessary, or because rate limited), so we are
989 * really we are wasting a lot of work here.
990 *
991 * We don't use m_copym() because it might return a reference
992 * to a shared cluster. Both this function and ip_output()
993 * assume exclusive access to the IP header in `m', so any
994 * data in a cluster may change before we reach icmp_error().
995 */
996 mcopy = m_gethdr(M_NOWAIT, m->m_type);
997 if (mcopy != NULL && !m_dup_pkthdr(mcopy, m, M_NOWAIT)) {
998 /*
999 * It's probably ok if the pkthdr dup fails (because
1000 * the deep copy of the tag chain failed), but for now
1001 * be conservative and just discard the copy since
1002 * code below may some day want the tags.
1003 */
1004 m_free(mcopy);
1005 mcopy = NULL;
1006 }
1007 if (mcopy != NULL) {
1008 mcopy->m_len = min(ntohs(ip->ip_len), M_TRAILINGSPACE(mcopy));
1009 mcopy->m_pkthdr.len = mcopy->m_len;
1010 m_copydata(m, 0, mcopy->m_len, mtod(mcopy, caddr_t));
1011 }
1012 #ifdef IPSTEALTH
1013 if (V_ipstealth == 0)
1014 #endif
1015 ip->ip_ttl -= IPTTLDEC;
1016 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1017 if (IPSEC_ENABLED(ipv4)) {
1018 if ((error = IPSEC_FORWARD(ipv4, m)) != 0) {
1019 /* mbuf consumed by IPsec */
1020 RO_NHFREE(&ro);
1021 m_freem(mcopy);
1022 if (error != EINPROGRESS)
1023 IPSTAT_INC(ips_cantforward);
1024 return;
1025 }
1026 /* No IPsec processing required */
1027 }
1028 #endif /* IPSEC */
1029 /*
1030 * If forwarding packet using same interface that it came in on,
1031 * perhaps should send a redirect to sender to shortcut a hop.
1032 * Only send redirect if source is sending directly to us,
1033 * and if packet was not source routed (or has any options).
1034 * Also, don't send redirect if forwarding using a default route
1035 * or a route modified by a redirect.
1036 */
1037 dest.s_addr = 0;
1038 if (!srcrt && V_ipsendredirects &&
1039 ia != NULL && ia->ia_ifp == m->m_pkthdr.rcvif) {
1040 struct nhop_object *nh;
1041
1042 nh = ro.ro_nh;
1043
1044 if (nh != NULL && ((nh->nh_flags & (NHF_REDIRECT|NHF_DEFAULT)) == 0)) {
1045 struct in_ifaddr *nh_ia = (struct in_ifaddr *)(nh->nh_ifa);
1046 u_long src = ntohl(ip->ip_src.s_addr);
1047
1048 if (nh_ia != NULL &&
1049 (src & nh_ia->ia_subnetmask) == nh_ia->ia_subnet) {
1050 /* Router requirements says to only send host redirects */
1051 type = ICMP_REDIRECT;
1052 code = ICMP_REDIRECT_HOST;
1053 if (nh->nh_flags & NHF_GATEWAY) {
1054 if (nh->gw_sa.sa_family == AF_INET)
1055 dest.s_addr = nh->gw4_sa.sin_addr.s_addr;
1056 else /* Do not redirect in case gw is AF_INET6 */
1057 type = 0;
1058 } else
1059 dest.s_addr = ip->ip_dst.s_addr;
1060 }
1061 }
1062 }
1063
1064 error = ip_output(m, NULL, &ro, IP_FORWARDING, NULL, NULL);
1065
1066 if (error == EMSGSIZE && ro.ro_nh)
1067 mtu = ro.ro_nh->nh_mtu;
1068 RO_NHFREE(&ro);
1069
1070 if (error)
1071 IPSTAT_INC(ips_cantforward);
1072 else {
1073 IPSTAT_INC(ips_forward);
1074 if (type)
1075 IPSTAT_INC(ips_redirectsent);
1076 else {
1077 if (mcopy)
1078 m_freem(mcopy);
1079 return;
1080 }
1081 }
1082 if (mcopy == NULL)
1083 return;
1084
1085 switch (error) {
1086 case 0: /* forwarded, but need redirect */
1087 /* type, code set above */
1088 break;
1089
1090 case ENETUNREACH:
1091 case EHOSTUNREACH:
1092 case ENETDOWN:
1093 case EHOSTDOWN:
1094 default:
1095 type = ICMP_UNREACH;
1096 code = ICMP_UNREACH_HOST;
1097 break;
1098
1099 case EMSGSIZE:
1100 type = ICMP_UNREACH;
1101 code = ICMP_UNREACH_NEEDFRAG;
1102 /*
1103 * If the MTU was set before make sure we are below the
1104 * interface MTU.
1105 * If the MTU wasn't set before use the interface mtu or
1106 * fall back to the next smaller mtu step compared to the
1107 * current packet size.
1108 */
1109 if (mtu != 0) {
1110 if (ia != NULL)
1111 mtu = min(mtu, ia->ia_ifp->if_mtu);
1112 } else {
1113 if (ia != NULL)
1114 mtu = ia->ia_ifp->if_mtu;
1115 else
1116 mtu = ip_next_mtu(ntohs(ip->ip_len), 0);
1117 }
1118 IPSTAT_INC(ips_cantfrag);
1119 break;
1120
1121 case ENOBUFS:
1122 case EACCES: /* ipfw denied packet */
1123 m_freem(mcopy);
1124 return;
1125 }
1126 icmp_error(mcopy, type, code, dest.s_addr, mtu);
1127 }
1128
1129 #define CHECK_SO_CT(sp, ct) \
1130 (((sp->so_options & SO_TIMESTAMP) && (sp->so_ts_clock == ct)) ? 1 : 0)
1131
1132 void
ip_savecontrol(struct inpcb * inp,struct mbuf ** mp,struct ip * ip,struct mbuf * m)1133 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
1134 struct mbuf *m)
1135 {
1136 bool stamped;
1137
1138 stamped = false;
1139 if ((inp->inp_socket->so_options & SO_BINTIME) ||
1140 CHECK_SO_CT(inp->inp_socket, SO_TS_BINTIME)) {
1141 struct bintime boottimebin, bt;
1142 struct timespec ts1;
1143
1144 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1145 M_TSTMP)) {
1146 mbuf_tstmp2timespec(m, &ts1);
1147 timespec2bintime(&ts1, &bt);
1148 getboottimebin(&boottimebin);
1149 bintime_add(&bt, &boottimebin);
1150 } else {
1151 bintime(&bt);
1152 }
1153 *mp = sbcreatecontrol(&bt, sizeof(bt), SCM_BINTIME,
1154 SOL_SOCKET, M_NOWAIT);
1155 if (*mp != NULL) {
1156 mp = &(*mp)->m_next;
1157 stamped = true;
1158 }
1159 }
1160 if (CHECK_SO_CT(inp->inp_socket, SO_TS_REALTIME_MICRO)) {
1161 struct bintime boottimebin, bt1;
1162 struct timespec ts1;
1163 struct timeval tv;
1164
1165 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1166 M_TSTMP)) {
1167 mbuf_tstmp2timespec(m, &ts1);
1168 timespec2bintime(&ts1, &bt1);
1169 getboottimebin(&boottimebin);
1170 bintime_add(&bt1, &boottimebin);
1171 bintime2timeval(&bt1, &tv);
1172 } else {
1173 microtime(&tv);
1174 }
1175 *mp = sbcreatecontrol((caddr_t)&tv, sizeof(tv), SCM_TIMESTAMP,
1176 SOL_SOCKET, M_NOWAIT);
1177 if (*mp != NULL) {
1178 mp = &(*mp)->m_next;
1179 stamped = true;
1180 }
1181 } else if (CHECK_SO_CT(inp->inp_socket, SO_TS_REALTIME)) {
1182 struct bintime boottimebin;
1183 struct timespec ts, ts1;
1184
1185 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1186 M_TSTMP)) {
1187 mbuf_tstmp2timespec(m, &ts);
1188 getboottimebin(&boottimebin);
1189 bintime2timespec(&boottimebin, &ts1);
1190 timespecadd(&ts, &ts1, &ts);
1191 } else {
1192 nanotime(&ts);
1193 }
1194 *mp = sbcreatecontrol(&ts, sizeof(ts), SCM_REALTIME,
1195 SOL_SOCKET, M_NOWAIT);
1196 if (*mp != NULL) {
1197 mp = &(*mp)->m_next;
1198 stamped = true;
1199 }
1200 } else if (CHECK_SO_CT(inp->inp_socket, SO_TS_MONOTONIC)) {
1201 struct timespec ts;
1202
1203 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1204 M_TSTMP))
1205 mbuf_tstmp2timespec(m, &ts);
1206 else
1207 nanouptime(&ts);
1208 *mp = sbcreatecontrol(&ts, sizeof(ts), SCM_MONOTONIC,
1209 SOL_SOCKET, M_NOWAIT);
1210 if (*mp != NULL) {
1211 mp = &(*mp)->m_next;
1212 stamped = true;
1213 }
1214 }
1215 if (stamped && (m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1216 M_TSTMP)) {
1217 struct sock_timestamp_info sti;
1218
1219 bzero(&sti, sizeof(sti));
1220 sti.st_info_flags = ST_INFO_HW;
1221 if ((m->m_flags & M_TSTMP_HPREC) != 0)
1222 sti.st_info_flags |= ST_INFO_HW_HPREC;
1223 *mp = sbcreatecontrol(&sti, sizeof(sti), SCM_TIME_INFO,
1224 SOL_SOCKET, M_NOWAIT);
1225 if (*mp != NULL)
1226 mp = &(*mp)->m_next;
1227 }
1228 if (inp->inp_flags & INP_RECVDSTADDR) {
1229 *mp = sbcreatecontrol(&ip->ip_dst, sizeof(struct in_addr),
1230 IP_RECVDSTADDR, IPPROTO_IP, M_NOWAIT);
1231 if (*mp)
1232 mp = &(*mp)->m_next;
1233 }
1234 if (inp->inp_flags & INP_RECVTTL) {
1235 *mp = sbcreatecontrol(&ip->ip_ttl, sizeof(u_char), IP_RECVTTL,
1236 IPPROTO_IP, M_NOWAIT);
1237 if (*mp)
1238 mp = &(*mp)->m_next;
1239 }
1240 #ifdef notyet
1241 /* XXX
1242 * Moving these out of udp_input() made them even more broken
1243 * than they already were.
1244 */
1245 /* options were tossed already */
1246 if (inp->inp_flags & INP_RECVOPTS) {
1247 *mp = sbcreatecontrol(opts_deleted_above,
1248 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP, M_NOWAIT);
1249 if (*mp)
1250 mp = &(*mp)->m_next;
1251 }
1252 /* ip_srcroute doesn't do what we want here, need to fix */
1253 if (inp->inp_flags & INP_RECVRETOPTS) {
1254 *mp = sbcreatecontrol(ip_srcroute(m), sizeof(struct in_addr),
1255 IP_RECVRETOPTS, IPPROTO_IP, M_NOWAIT);
1256 if (*mp)
1257 mp = &(*mp)->m_next;
1258 }
1259 #endif
1260 if (inp->inp_flags & INP_RECVIF) {
1261 struct ifnet *ifp;
1262 struct sdlbuf {
1263 struct sockaddr_dl sdl;
1264 u_char pad[32];
1265 } sdlbuf;
1266 struct sockaddr_dl *sdp;
1267 struct sockaddr_dl *sdl2 = &sdlbuf.sdl;
1268
1269 if ((ifp = m->m_pkthdr.rcvif)) {
1270 sdp = (struct sockaddr_dl *)ifp->if_addr->ifa_addr;
1271 /*
1272 * Change our mind and don't try copy.
1273 */
1274 if (sdp->sdl_family != AF_LINK ||
1275 sdp->sdl_len > sizeof(sdlbuf)) {
1276 goto makedummy;
1277 }
1278 bcopy(sdp, sdl2, sdp->sdl_len);
1279 } else {
1280 makedummy:
1281 sdl2->sdl_len =
1282 offsetof(struct sockaddr_dl, sdl_data[0]);
1283 sdl2->sdl_family = AF_LINK;
1284 sdl2->sdl_index = 0;
1285 sdl2->sdl_nlen = sdl2->sdl_alen = sdl2->sdl_slen = 0;
1286 }
1287 *mp = sbcreatecontrol(sdl2, sdl2->sdl_len, IP_RECVIF,
1288 IPPROTO_IP, M_NOWAIT);
1289 if (*mp)
1290 mp = &(*mp)->m_next;
1291 }
1292 if (inp->inp_flags & INP_RECVTOS) {
1293 *mp = sbcreatecontrol(&ip->ip_tos, sizeof(u_char), IP_RECVTOS,
1294 IPPROTO_IP, M_NOWAIT);
1295 if (*mp)
1296 mp = &(*mp)->m_next;
1297 }
1298
1299 if (inp->inp_flags2 & INP_RECVFLOWID) {
1300 uint32_t flowid, flow_type;
1301
1302 flowid = m->m_pkthdr.flowid;
1303 flow_type = M_HASHTYPE_GET(m);
1304
1305 /*
1306 * XXX should handle the failure of one or the
1307 * other - don't populate both?
1308 */
1309 *mp = sbcreatecontrol(&flowid, sizeof(uint32_t), IP_FLOWID,
1310 IPPROTO_IP, M_NOWAIT);
1311 if (*mp)
1312 mp = &(*mp)->m_next;
1313 *mp = sbcreatecontrol(&flow_type, sizeof(uint32_t),
1314 IP_FLOWTYPE, IPPROTO_IP, M_NOWAIT);
1315 if (*mp)
1316 mp = &(*mp)->m_next;
1317 }
1318
1319 #ifdef RSS
1320 if (inp->inp_flags2 & INP_RECVRSSBUCKETID) {
1321 uint32_t flowid, flow_type;
1322 uint32_t rss_bucketid;
1323
1324 flowid = m->m_pkthdr.flowid;
1325 flow_type = M_HASHTYPE_GET(m);
1326
1327 if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) {
1328 *mp = sbcreatecontrol(&rss_bucketid, sizeof(uint32_t),
1329 IP_RSSBUCKETID, IPPROTO_IP, M_NOWAIT);
1330 if (*mp)
1331 mp = &(*mp)->m_next;
1332 }
1333 }
1334 #endif
1335 }
1336
1337 /*
1338 * XXXRW: Multicast routing code in ip_mroute.c is generally MPSAFE, but the
1339 * ip_rsvp and ip_rsvp_on variables need to be interlocked with rsvp_on
1340 * locking. This code remains in ip_input.c as ip_mroute.c is optionally
1341 * compiled.
1342 */
1343 VNET_DEFINE_STATIC(int, ip_rsvp_on);
1344 VNET_DEFINE(struct socket *, ip_rsvpd);
1345
1346 #define V_ip_rsvp_on VNET(ip_rsvp_on)
1347
1348 int
ip_rsvp_init(struct socket * so)1349 ip_rsvp_init(struct socket *so)
1350 {
1351
1352 if (V_ip_rsvpd != NULL)
1353 return EADDRINUSE;
1354
1355 V_ip_rsvpd = so;
1356 /*
1357 * This may seem silly, but we need to be sure we don't over-increment
1358 * the RSVP counter, in case something slips up.
1359 */
1360 if (!V_ip_rsvp_on) {
1361 V_ip_rsvp_on = 1;
1362 V_rsvp_on++;
1363 }
1364
1365 return 0;
1366 }
1367
1368 int
ip_rsvp_done(void)1369 ip_rsvp_done(void)
1370 {
1371
1372 V_ip_rsvpd = NULL;
1373 /*
1374 * This may seem silly, but we need to be sure we don't over-decrement
1375 * the RSVP counter, in case something slips up.
1376 */
1377 if (V_ip_rsvp_on) {
1378 V_ip_rsvp_on = 0;
1379 V_rsvp_on--;
1380 }
1381 return 0;
1382 }
1383
1384 int
rsvp_input(struct mbuf ** mp,int * offp,int proto)1385 rsvp_input(struct mbuf **mp, int *offp, int proto)
1386 {
1387 struct mbuf *m;
1388
1389 m = *mp;
1390 *mp = NULL;
1391
1392 if (rsvp_input_p) { /* call the real one if loaded */
1393 *mp = m;
1394 rsvp_input_p(mp, offp, proto);
1395 return (IPPROTO_DONE);
1396 }
1397
1398 /* Can still get packets with rsvp_on = 0 if there is a local member
1399 * of the group to which the RSVP packet is addressed. But in this
1400 * case we want to throw the packet away.
1401 */
1402
1403 if (!V_rsvp_on) {
1404 m_freem(m);
1405 return (IPPROTO_DONE);
1406 }
1407
1408 if (V_ip_rsvpd != NULL) {
1409 *mp = m;
1410 rip_input(mp, offp, proto);
1411 return (IPPROTO_DONE);
1412 }
1413 /* Drop the packet */
1414 m_freem(m);
1415 return (IPPROTO_DONE);
1416 }
1417