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_rss.h"
37 #include "opt_sctp.h"
38
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/hhook.h>
42 #include <sys/mbuf.h>
43 #include <sys/malloc.h>
44 #include <sys/domain.h>
45 #include <sys/protosw.h>
46 #include <sys/socket.h>
47 #include <sys/time.h>
48 #include <sys/kernel.h>
49 #include <sys/lock.h>
50 #include <sys/rmlock.h>
51 #include <sys/rwlock.h>
52 #include <sys/sdt.h>
53 #include <sys/syslog.h>
54 #include <sys/sysctl.h>
55 #include <sys/hash.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 #ifdef IPCTL_DEFMTU
180 SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW,
181 &ip_mtu, 0, "Default MTU");
182 #endif
183
184 #ifdef IPSTEALTH
185 VNET_DEFINE(int, ipstealth);
186 SYSCTL_INT(_net_inet_ip, OID_AUTO, stealth, CTLFLAG_VNET | CTLFLAG_RW,
187 &VNET_NAME(ipstealth), 0,
188 "IP stealth mode, no TTL decrementation on forwarding");
189 #endif
190
191 /*
192 * IP statistics are stored in the "array" of counter(9)s.
193 */
194 VNET_PCPUSTAT_DEFINE(struct ipstat, ipstat);
195 VNET_PCPUSTAT_SYSINIT(ipstat);
196 SYSCTL_VNET_PCPUSTAT(_net_inet_ip, IPCTL_STATS, stats, struct ipstat, ipstat,
197 "IP statistics (struct ipstat, netinet/ip_var.h)");
198
199 #ifdef VIMAGE
200 VNET_PCPUSTAT_SYSUNINIT(ipstat);
201 #endif /* VIMAGE */
202
203 /*
204 * Kernel module interface for updating ipstat. The argument is an index
205 * into ipstat treated as an array.
206 */
207 void
kmod_ipstat_inc(int statnum)208 kmod_ipstat_inc(int statnum)
209 {
210
211 counter_u64_add(VNET(ipstat)[statnum], 1);
212 }
213
214 void
kmod_ipstat_dec(int statnum)215 kmod_ipstat_dec(int statnum)
216 {
217
218 counter_u64_add(VNET(ipstat)[statnum], -1);
219 }
220
221 static int
sysctl_netinet_intr_queue_maxlen(SYSCTL_HANDLER_ARGS)222 sysctl_netinet_intr_queue_maxlen(SYSCTL_HANDLER_ARGS)
223 {
224 int error, qlimit;
225
226 netisr_getqlimit(&ip_nh, &qlimit);
227 error = sysctl_handle_int(oidp, &qlimit, 0, req);
228 if (error || !req->newptr)
229 return (error);
230 if (qlimit < 1)
231 return (EINVAL);
232 return (netisr_setqlimit(&ip_nh, qlimit));
233 }
234 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen,
235 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0,
236 sysctl_netinet_intr_queue_maxlen, "I",
237 "Maximum size of the IP input queue");
238
239 static int
sysctl_netinet_intr_queue_drops(SYSCTL_HANDLER_ARGS)240 sysctl_netinet_intr_queue_drops(SYSCTL_HANDLER_ARGS)
241 {
242 u_int64_t qdrops_long;
243 int error, qdrops;
244
245 netisr_getqdrops(&ip_nh, &qdrops_long);
246 qdrops = qdrops_long;
247 error = sysctl_handle_int(oidp, &qdrops, 0, req);
248 if (error || !req->newptr)
249 return (error);
250 if (qdrops != 0)
251 return (EINVAL);
252 netisr_clearqdrops(&ip_nh);
253 return (0);
254 }
255
256 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops,
257 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
258 0, 0, sysctl_netinet_intr_queue_drops, "I",
259 "Number of packets dropped from the IP input queue");
260
261 #ifdef RSS
262 static int
sysctl_netinet_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS)263 sysctl_netinet_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS)
264 {
265 int error, qlimit;
266
267 netisr_getqlimit(&ip_direct_nh, &qlimit);
268 error = sysctl_handle_int(oidp, &qlimit, 0, req);
269 if (error || !req->newptr)
270 return (error);
271 if (qlimit < 1)
272 return (EINVAL);
273 return (netisr_setqlimit(&ip_direct_nh, qlimit));
274 }
275 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRDQMAXLEN, intr_direct_queue_maxlen,
276 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
277 0, 0, sysctl_netinet_intr_direct_queue_maxlen,
278 "I", "Maximum size of the IP direct input queue");
279
280 static int
sysctl_netinet_intr_direct_queue_drops(SYSCTL_HANDLER_ARGS)281 sysctl_netinet_intr_direct_queue_drops(SYSCTL_HANDLER_ARGS)
282 {
283 u_int64_t qdrops_long;
284 int error, qdrops;
285
286 netisr_getqdrops(&ip_direct_nh, &qdrops_long);
287 qdrops = qdrops_long;
288 error = sysctl_handle_int(oidp, &qdrops, 0, req);
289 if (error || !req->newptr)
290 return (error);
291 if (qdrops != 0)
292 return (EINVAL);
293 netisr_clearqdrops(&ip_direct_nh);
294 return (0);
295 }
296
297 SYSCTL_PROC(_net_inet_ip, IPCTL_INTRDQDROPS, intr_direct_queue_drops,
298 CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0,
299 sysctl_netinet_intr_direct_queue_drops, "I",
300 "Number of packets dropped from the IP direct input queue");
301 #endif /* RSS */
302
303 /*
304 * IP initialization: fill in IP protocol switch table.
305 * All protocols not implemented in kernel go to raw IP protocol handler.
306 */
307 static void
ip_vnet_init(void * arg __unused)308 ip_vnet_init(void *arg __unused)
309 {
310 CK_STAILQ_INIT(&V_in_ifaddrhead);
311
312 struct hashalloc_args ha = {
313 .size = INADDR_NHASH,
314 .mtype = M_IFADDR,
315 .mflags = M_WAITOK,
316 .head = HASH_HEAD_CK_LIST,
317 };
318 V_in_ifaddrhashtbl = hashalloc(&ha);
319 V_in_ifaddrhmask = ha.size - 1;
320
321 /* Initialize IP reassembly queue. */
322 ipreass_vnet_init();
323
324 /* Initialize packet filter hooks. */
325 struct pfil_head_args pa = {
326 .pa_version = PFIL_VERSION,
327 .pa_flags = PFIL_IN | PFIL_OUT,
328 .pa_type = PFIL_TYPE_IP4,
329 .pa_headname = PFIL_INET_NAME,
330 };
331 V_inet_pfil_head = pfil_head_register(&pa);
332
333 pa.pa_flags = PFIL_OUT;
334 pa.pa_headname = PFIL_INET_LOCAL_NAME;
335 V_inet_local_pfil_head = pfil_head_register(&pa);
336
337 if (hhook_head_register(HHOOK_TYPE_IPSEC_IN, AF_INET,
338 &V_ipsec_hhh_in[HHOOK_IPSEC_INET],
339 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0)
340 printf("%s: WARNING: unable to register input helper hook\n",
341 __func__);
342 if (hhook_head_register(HHOOK_TYPE_IPSEC_OUT, AF_INET,
343 &V_ipsec_hhh_out[HHOOK_IPSEC_INET],
344 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0)
345 printf("%s: WARNING: unable to register output helper hook\n",
346 __func__);
347
348 #ifdef VIMAGE
349 netisr_register_vnet(&ip_nh);
350 #ifdef RSS
351 netisr_register_vnet(&ip_direct_nh);
352 #endif
353 #endif
354 }
355 VNET_SYSINIT(ip_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
356 ip_vnet_init, NULL);
357
358 static void
ip_init(const void * unused __unused)359 ip_init(const void *unused __unused)
360 {
361 struct ifnet *ifp;
362
363 ipreass_init();
364
365 /*
366 * Register statically compiled protocols, that are unlikely to
367 * ever become dynamic.
368 */
369 IPPROTO_REGISTER(IPPROTO_ICMP, icmp_input, NULL);
370 IPPROTO_REGISTER(IPPROTO_IGMP, igmp_input, NULL);
371 IPPROTO_REGISTER(IPPROTO_RSVP, rsvp_input, NULL);
372 IPPROTO_REGISTER(IPPROTO_IPV4, encap4_input, NULL);
373 IPPROTO_REGISTER(IPPROTO_MOBILE, encap4_input, NULL);
374 IPPROTO_REGISTER(IPPROTO_ETHERIP, encap4_input, NULL);
375 IPPROTO_REGISTER(IPPROTO_GRE, encap4_input, NULL);
376 IPPROTO_REGISTER(IPPROTO_IPV6, encap4_input, NULL);
377 IPPROTO_REGISTER(IPPROTO_PIM, encap4_input, NULL);
378 #ifdef SCTP /* XXX: has a loadable & static version */
379 IPPROTO_REGISTER(IPPROTO_SCTP, sctp_input, sctp_ctlinput);
380 #endif
381
382 netisr_register(&ip_nh);
383 #ifdef RSS
384 netisr_register(&ip_direct_nh);
385 #endif
386 /*
387 * XXXGL: we use SYSINIT() here, but go over V_ifnet. It was the same
388 * way before dom_ifattach removal. This worked because when any
389 * non-default vnet is created, there are no interfaces inside.
390 * Eventually this needs to be fixed.
391 */
392 CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link)
393 in_ifattach(NULL, ifp);
394 }
395 SYSINIT(ip_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip_init, NULL);
396
397 #ifdef VIMAGE
398 static void
ip_destroy(void * unused __unused)399 ip_destroy(void *unused __unused)
400 {
401 int error;
402
403 #ifdef RSS
404 netisr_unregister_vnet(&ip_direct_nh);
405 #endif
406 netisr_unregister_vnet(&ip_nh);
407
408 pfil_head_unregister(V_inet_pfil_head);
409 error = hhook_head_deregister(V_ipsec_hhh_in[HHOOK_IPSEC_INET]);
410 if (error != 0) {
411 printf("%s: WARNING: unable to deregister input helper hook "
412 "type HHOOK_TYPE_IPSEC_IN, id HHOOK_IPSEC_INET: "
413 "error %d returned\n", __func__, error);
414 }
415 error = hhook_head_deregister(V_ipsec_hhh_out[HHOOK_IPSEC_INET]);
416 if (error != 0) {
417 printf("%s: WARNING: unable to deregister output helper hook "
418 "type HHOOK_TYPE_IPSEC_OUT, id HHOOK_IPSEC_INET: "
419 "error %d returned\n", __func__, error);
420 }
421
422 /* Remove the IPv4 addresses from all interfaces. */
423 in_ifscrub_all();
424
425 /* Make sure the IPv4 routes are gone as well. */
426 rib_flush_routes_family(AF_INET);
427
428 /* Destroy IP reassembly queue. */
429 ipreass_destroy();
430
431 /* Cleanup in_ifaddr hash table; should be empty. */
432 struct hashalloc_args ha = {
433 .mtype = M_IFADDR,
434 .head = HASH_HEAD_CK_LIST,
435 .size = V_in_ifaddrhmask + 1,
436 };
437 hashfree(V_in_ifaddrhashtbl, &ha);
438 }
439
440 VNET_SYSUNINIT(ip, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip_destroy, NULL);
441 #endif
442
443 #ifdef RSS
444 /*
445 * IP direct input routine.
446 *
447 * This is called when reinjecting completed fragments where
448 * all of the previous checking and book-keeping has been done.
449 */
450 void
ip_direct_input(struct mbuf * m)451 ip_direct_input(struct mbuf *m)
452 {
453 struct ip *ip;
454 int hlen;
455
456 ip = mtod(m, struct ip *);
457 hlen = ip->ip_hl << 2;
458
459 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
460 if (IPSEC_ENABLED(ipv4)) {
461 if (IPSEC_INPUT(ipv4, m, hlen, ip->ip_p) != 0)
462 return;
463 }
464 #endif /* IPSEC */
465 IPSTAT_INC(ips_delivered);
466 ip_protox[ip->ip_p](&m, &hlen, ip->ip_p);
467 }
468 #endif
469
470 /*
471 * Ip input routine. Checksum and byte swap header. If fragmented
472 * try to reassemble. Process options. Pass to next level.
473 */
474 void
ip_input(struct mbuf * m)475 ip_input(struct mbuf *m)
476 {
477 struct ip *ip = NULL;
478 struct in_ifaddr *ia = NULL;
479 struct ifaddr *ifa;
480 struct ifnet *ifp;
481 int hlen = 0;
482 uint16_t sum, ip_len;
483 int dchg = 0; /* dest changed after fw */
484 struct in_addr odst; /* original dst address */
485 bool strong_es;
486
487 M_ASSERTPKTHDR(m);
488 NET_EPOCH_ASSERT();
489
490 if (m->m_flags & M_FASTFWD_OURS) {
491 m->m_flags &= ~M_FASTFWD_OURS;
492 /* Set up some basics that will be used later. */
493 ip = mtod(m, struct ip *);
494 hlen = ip->ip_hl << 2;
495 ip_len = ntohs(ip->ip_len);
496 goto ours;
497 }
498
499 IPSTAT_INC(ips_total);
500
501 if (__predict_false(m->m_pkthdr.len < sizeof(struct ip)))
502 goto tooshort;
503
504 if (m->m_len < sizeof(struct ip)) {
505 m = m_pullup(m, sizeof(struct ip));
506 if (__predict_false(m == NULL)) {
507 IPSTAT_INC(ips_toosmall);
508 return;
509 }
510 }
511 ip = mtod(m, struct ip *);
512
513 if (__predict_false(ip->ip_v != IPVERSION)) {
514 IPSTAT_INC(ips_badvers);
515 goto bad;
516 }
517
518 hlen = ip->ip_hl << 2;
519 if (__predict_false(hlen < sizeof(struct ip))) { /* minimum header length */
520 IPSTAT_INC(ips_badhlen);
521 goto bad;
522 }
523 if (hlen > m->m_len) {
524 m = m_pullup(m, hlen);
525 if (__predict_false(m == NULL)) {
526 IPSTAT_INC(ips_badhlen);
527 return;
528 }
529 ip = mtod(m, struct ip *);
530 }
531
532 IP_PROBE(receive, NULL, NULL, ip, m->m_pkthdr.rcvif, ip, NULL);
533
534 /* IN_LOOPBACK must not appear on the wire - RFC1122 */
535 ifp = m->m_pkthdr.rcvif;
536 if (IN_LOOPBACK(ntohl(ip->ip_dst.s_addr)) ||
537 IN_LOOPBACK(ntohl(ip->ip_src.s_addr))) {
538 if ((ifp->if_flags & IFF_LOOPBACK) == 0) {
539 IPSTAT_INC(ips_badaddr);
540 goto bad;
541 }
542 }
543
544 if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) {
545 sum = !(m->m_pkthdr.csum_flags & CSUM_IP_VALID);
546 } else if (m->m_pkthdr.csum_flags & CSUM_IP) {
547 /*
548 * Packet from local host that offloaded checksum computation.
549 * Checksum not required since the packet wasn't on the wire.
550 */
551 sum = 0;
552 } else {
553 if (hlen == sizeof(struct ip)) {
554 sum = in_cksum_hdr(ip);
555 } else {
556 sum = in_cksum(m, hlen);
557 }
558 }
559 if (__predict_false(sum)) {
560 IPSTAT_INC(ips_badsum);
561 goto bad;
562 }
563
564 ip_len = ntohs(ip->ip_len);
565 if (__predict_false(ip_len < hlen)) {
566 IPSTAT_INC(ips_badlen);
567 goto bad;
568 }
569
570 /*
571 * Check that the amount of data in the buffers
572 * is as at least much as the IP header would have us expect.
573 * Trim mbufs if longer than we expect.
574 * Drop packet if shorter than we expect.
575 */
576 if (__predict_false(m->m_pkthdr.len < ip_len)) {
577 tooshort:
578 IPSTAT_INC(ips_tooshort);
579 goto bad;
580 }
581 if (m->m_pkthdr.len > ip_len) {
582 if (m->m_len == m->m_pkthdr.len) {
583 m->m_len = ip_len;
584 m->m_pkthdr.len = ip_len;
585 } else
586 m_adj(m, ip_len - m->m_pkthdr.len);
587 }
588
589 /*
590 * Try to forward the packet, but if we fail continue.
591 * ip_tryforward() may generate redirects these days.
592 * XXX the logic below falling through to normal processing
593 * if redirects are required should be revisited as well.
594 * ip_tryforward() does inbound and outbound packet firewall
595 * processing. If firewall has decided that destination becomes
596 * our local address, it sets M_FASTFWD_OURS flag. In this
597 * case skip another inbound firewall processing and update
598 * ip pointer.
599 */
600 if (V_ipforwarding != 0
601 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
602 && (!IPSEC_ENABLED(ipv4) ||
603 IPSEC_CAPS(ipv4, m, IPSEC_CAP_OPERABLE) == 0)
604 #endif
605 ) {
606 /*
607 * ip_dooptions() was run so we can ignore the source route (or
608 * any IP options case) case for redirects in ip_tryforward().
609 */
610 if ((m = ip_tryforward(m)) == NULL)
611 return;
612 if (m->m_flags & M_FASTFWD_OURS) {
613 m->m_flags &= ~M_FASTFWD_OURS;
614 ip = mtod(m, struct ip *);
615 goto ours;
616 }
617 }
618
619 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
620 /*
621 * Bypass packet filtering for packets previously handled by IPsec.
622 */
623 if (IPSEC_ENABLED(ipv4) &&
624 IPSEC_CAPS(ipv4, m, IPSEC_CAP_BYPASS_FILTER) != 0)
625 goto passin;
626 #endif
627
628 /*
629 * Run through list of hooks for input packets.
630 *
631 * NB: Beware of the destination address changing (e.g.
632 * by NAT rewriting). When this happens, tell
633 * ip_forward to do the right thing.
634 */
635
636 /* Jump over all PFIL processing if hooks are not active. */
637 if (!PFIL_HOOKED_IN(V_inet_pfil_head))
638 goto passin;
639
640 odst = ip->ip_dst;
641 if (pfil_mbuf_in(V_inet_pfil_head, &m, ifp, NULL) !=
642 PFIL_PASS)
643 return;
644
645 ip = mtod(m, struct ip *);
646 dchg = (odst.s_addr != ip->ip_dst.s_addr);
647
648 if (m->m_flags & M_FASTFWD_OURS) {
649 m->m_flags &= ~M_FASTFWD_OURS;
650 goto ours;
651 }
652 if (m->m_flags & M_IP_NEXTHOP) {
653 if (m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) {
654 /*
655 * Directly ship the packet on. This allows
656 * forwarding packets originally destined to us
657 * to some other directly connected host.
658 */
659 ip_forward(m, 1);
660 return;
661 }
662 }
663 passin:
664 /*
665 * The unspecified address can appear only as a src address - RFC1122.
666 *
667 * The check is deferred to here to give firewalls a chance to block
668 * (and log) such packets. ip_tryforward() will not process such
669 * packets.
670 */
671 if (__predict_false(ntohl(ip->ip_dst.s_addr) == INADDR_ANY)) {
672 IPSTAT_INC(ips_badaddr);
673 goto bad;
674 }
675
676 /*
677 * Process options and, if not destined for us,
678 * ship it on. ip_dooptions returns 1 when an
679 * error was detected (causing an icmp message
680 * to be sent and the original packet to be freed).
681 */
682 if (hlen > sizeof (struct ip) && ip_dooptions(m, 0))
683 return;
684
685 /* greedy RSVP, snatches any PATH packet of the RSVP protocol and no
686 * matter if it is destined to another node, or whether it is
687 * a multicast one, RSVP wants it! and prevents it from being forwarded
688 * anywhere else. Also checks if the rsvp daemon is running before
689 * grabbing the packet.
690 */
691 if (ip->ip_p == IPPROTO_RSVP && V_rsvp_on)
692 goto ours;
693
694 /*
695 * Check our list of addresses, to see if the packet is for us.
696 * If we don't have any addresses, assume any unicast packet
697 * we receive might be for us (and let the upper layers deal
698 * with it).
699 */
700 if (CK_STAILQ_EMPTY(&V_in_ifaddrhead) &&
701 (m->m_flags & (M_MCAST|M_BCAST)) == 0)
702 goto ours;
703
704 /*
705 * Enable a consistency check between the destination address
706 * and the arrival interface for a unicast packet (the RFC 1122
707 * strong ES model) with a list of additional predicates:
708 * - if IP forwarding is disabled
709 * - the packet is not locally generated
710 * - the packet is not subject to 'ipfw fwd'
711 * - Interface is not running CARP. If the packet got here, we already
712 * checked it with carp_iamatch() and carp_forus().
713 */
714 strong_es = V_ip_strong_es && (V_ipforwarding == 0) &&
715 ((ifp->if_flags & IFF_LOOPBACK) == 0) &&
716 ifp->if_carp == NULL && (dchg == 0);
717
718 /*
719 * Check for exact addresses in the hash bucket.
720 */
721 CK_LIST_FOREACH(ia, INADDR_HASH(ip->ip_dst.s_addr), ia_hash) {
722 if (IA_SIN(ia)->sin_addr.s_addr != ip->ip_dst.s_addr)
723 continue;
724
725 /*
726 * net.inet.ip.rfc1122_strong_es: the address matches, verify
727 * that the packet arrived via the correct interface.
728 */
729 if (__predict_false(strong_es && ia->ia_ifp != ifp)) {
730 IPSTAT_INC(ips_badaddr);
731 goto bad;
732 }
733
734 /*
735 * net.inet.ip.source_address_validation: drop incoming
736 * packets that pretend to be ours.
737 */
738 if (V_ip_sav && !(ifp->if_flags & IFF_LOOPBACK) &&
739 __predict_false(in_localip_fib(ip->ip_src, ifp->if_fib))) {
740 IPSTAT_INC(ips_badaddr);
741 goto bad;
742 }
743
744 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
745 counter_u64_add(ia->ia_ifa.ifa_ibytes, m->m_pkthdr.len);
746 goto ours;
747 }
748
749 /*
750 * Check for broadcast addresses.
751 *
752 * Only accept broadcast packets that arrive via the matching
753 * interface. Reception of forwarded directed broadcasts would
754 * be handled via ip_forward() and ether_output() with the loopback
755 * into the stack for SIMPLEX interfaces handled by ether_output().
756 */
757 if (ifp->if_flags & IFF_BROADCAST) {
758 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
759 if (ifa->ifa_addr->sa_family != AF_INET)
760 continue;
761 ia = ifatoia(ifa);
762 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr ==
763 ip->ip_dst.s_addr) {
764 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
765 counter_u64_add(ia->ia_ifa.ifa_ibytes,
766 m->m_pkthdr.len);
767 goto ours;
768 }
769 #ifdef BOOTP_COMPAT
770 if (IA_SIN(ia)->sin_addr.s_addr == INADDR_ANY) {
771 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
772 counter_u64_add(ia->ia_ifa.ifa_ibytes,
773 m->m_pkthdr.len);
774 goto ours;
775 }
776 #endif
777 }
778 ia = NULL;
779 }
780 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
781 /*
782 * RFC 3927 2.7: Do not forward multicast packets from
783 * IN_LINKLOCAL.
784 */
785 if (V_ip_mrouting_enabled &&
786 !IN_LINKLOCAL(ntohl(ip->ip_src.s_addr))) {
787 /*
788 * If we are acting as a multicast router, all
789 * incoming multicast packets are passed to the
790 * kernel-level multicast forwarding function.
791 * The packet is returned (relatively) intact; if
792 * ip_mforward() returns a non-zero value, the packet
793 * must be discarded, else it may be accepted below.
794 */
795 if (ip_mforward && ip_mforward(ip, ifp, m, 0) != 0) {
796 IPSTAT_INC(ips_cantforward);
797 m_freem(m);
798 return;
799 }
800
801 /*
802 * The process-level routing daemon needs to receive
803 * all multicast IGMP packets, whether or not this
804 * host belongs to their destination groups.
805 */
806 if (ip->ip_p == IPPROTO_IGMP) {
807 goto ours;
808 }
809 IPSTAT_INC(ips_forward);
810 }
811 /*
812 * Assume the packet is for us, to avoid prematurely taking
813 * a lock on the in_multi hash. Protocols must perform
814 * their own filtering and update statistics accordingly.
815 */
816 goto ours;
817 }
818 if (in_broadcast(ip->ip_dst))
819 goto ours;
820 /* RFC 3927 2.7: Do not forward packets to or from IN_LINKLOCAL. */
821 if (IN_LINKLOCAL(ntohl(ip->ip_dst.s_addr)) ||
822 IN_LINKLOCAL(ntohl(ip->ip_src.s_addr))) {
823 IPSTAT_INC(ips_cantforward);
824 m_freem(m);
825 return;
826 }
827
828 /*
829 * Not for us; forward if possible and desirable.
830 */
831 if (V_ipforwarding == 0) {
832 IPSTAT_INC(ips_cantforward);
833 m_freem(m);
834 } else {
835 ip_forward(m, dchg);
836 }
837 return;
838
839 ours:
840 #ifdef IPSTEALTH
841 /*
842 * IPSTEALTH: Process non-routing options only
843 * if the packet is destined for us.
844 */
845 if (V_ipstealth && hlen > sizeof (struct ip) && ip_dooptions(m, 1))
846 return;
847 #endif /* IPSTEALTH */
848
849 /*
850 * We are going to ship the packet to the local protocol stack. Call the
851 * filter again for this 'output' action, allowing redirect-like rules
852 * to adjust the source address.
853 */
854 if (PFIL_HOOKED_OUT(V_inet_local_pfil_head)) {
855 if (pfil_mbuf_out(V_inet_local_pfil_head, &m, V_loif, NULL) !=
856 PFIL_PASS)
857 return;
858 ip = mtod(m, struct ip *);
859 }
860
861 /*
862 * Attempt reassembly; if it succeeds, proceed.
863 * ip_reass() will return a different mbuf.
864 */
865 if (ip->ip_off & htons(IP_MF | IP_OFFMASK)) {
866 /* XXXGL: shouldn't we save & set m_flags? */
867 m = ip_reass(m);
868 if (m == NULL)
869 return;
870 ip = mtod(m, struct ip *);
871 /* Get the header length of the reassembled packet */
872 hlen = ip->ip_hl << 2;
873 }
874
875 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
876 if (IPSEC_ENABLED(ipv4)) {
877 if (IPSEC_INPUT(ipv4, m, hlen, ip->ip_p) != 0)
878 return;
879 }
880 #endif /* IPSEC */
881
882 /*
883 * Switch out to protocol's input routine.
884 */
885 IPSTAT_INC(ips_delivered);
886
887 ip_protox[ip->ip_p](&m, &hlen, ip->ip_p);
888 return;
889 bad:
890 m_freem(m);
891 }
892
893 int
ipproto_register(uint8_t proto,ipproto_input_t input,ipproto_ctlinput_t ctl)894 ipproto_register(uint8_t proto, ipproto_input_t input, ipproto_ctlinput_t ctl)
895 {
896
897 MPASS(proto > 0);
898
899 /*
900 * The protocol slot must not be occupied by another protocol
901 * already. An index pointing to rip_input() is unused.
902 */
903 if (ip_protox[proto] == rip_input) {
904 ip_protox[proto] = input;
905 ip_ctlprotox[proto] = ctl;
906 return (0);
907 } else
908 return (EEXIST);
909 }
910
911 int
ipproto_unregister(uint8_t proto)912 ipproto_unregister(uint8_t proto)
913 {
914
915 MPASS(proto > 0);
916
917 if (ip_protox[proto] != rip_input) {
918 ip_protox[proto] = rip_input;
919 ip_ctlprotox[proto] = rip_ctlinput;
920 return (0);
921 } else
922 return (ENOENT);
923 }
924
925 /*
926 * Forward a packet. If some error occurs return the sender
927 * an icmp packet. Note we can't always generate a meaningful
928 * icmp message because icmp doesn't have a large enough repertoire
929 * of codes and types.
930 *
931 * If not forwarding, just drop the packet. This could be confusing
932 * if ipforwarding was zero but some routing protocol was advancing
933 * us as a gateway to somewhere. However, we must let the routing
934 * protocol deal with that.
935 *
936 * The srcrt parameter indicates whether the packet is being forwarded
937 * via a source route.
938 */
939 void
ip_forward(struct mbuf * m,int srcrt)940 ip_forward(struct mbuf *m, int srcrt)
941 {
942 struct ip *ip = mtod(m, struct ip *);
943 struct in_ifaddr *ia;
944 struct mbuf *mcopy;
945 struct sockaddr_in *sin;
946 struct in_addr dest;
947 struct route ro;
948 uint32_t flowid;
949 int error, type = 0, code = 0, mtu = 0;
950
951 NET_EPOCH_ASSERT();
952
953 if (m->m_flags & (M_BCAST|M_MCAST) || !in_canforward(ip->ip_dst)) {
954 IPSTAT_INC(ips_cantforward);
955 m_freem(m);
956 return;
957 }
958 if (
959 #ifdef IPSTEALTH
960 V_ipstealth == 0 &&
961 #endif
962 ip->ip_ttl <= IPTTLDEC) {
963 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, 0, 0);
964 return;
965 }
966
967 bzero(&ro, sizeof(ro));
968 sin = (struct sockaddr_in *)&ro.ro_dst;
969 sin->sin_family = AF_INET;
970 sin->sin_len = sizeof(*sin);
971 sin->sin_addr = ip->ip_dst;
972 flowid = m->m_pkthdr.flowid;
973 ro.ro_nh = fib4_lookup(M_GETFIB(m), ip->ip_dst, 0, NHR_REF, flowid);
974 if (ro.ro_nh != NULL) {
975 if (ro.ro_nh->nh_flags & (NHF_BLACKHOLE | NHF_BROADCAST)) {
976 IPSTAT_INC(ips_cantforward);
977 m_freem(m);
978 NH_FREE(ro.ro_nh);
979 return;
980 }
981 if (ro.ro_nh->nh_flags & NHF_REJECT) {
982 IPSTAT_INC(ips_cantforward);
983 NH_FREE(ro.ro_nh);
984 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0);
985 return;
986 }
987 ia = ifatoia(ro.ro_nh->nh_ifa);
988 } else
989 ia = NULL;
990 /*
991 * Save the IP header and at most 8 bytes of the payload,
992 * in case we need to generate an ICMP message to the src.
993 *
994 * XXX this can be optimized a lot by saving the data in a local
995 * buffer on the stack (72 bytes at most), and only allocating the
996 * mbuf if really necessary. The vast majority of the packets
997 * are forwarded without having to send an ICMP back (either
998 * because unnecessary, or because rate limited), so we are
999 * really we are wasting a lot of work here.
1000 *
1001 * We don't use m_copym() because it might return a reference
1002 * to a shared cluster. Both this function and ip_output()
1003 * assume exclusive access to the IP header in `m', so any
1004 * data in a cluster may change before we reach icmp_error().
1005 */
1006 mcopy = m_gethdr(M_NOWAIT, m->m_type);
1007 if (mcopy != NULL && !m_dup_pkthdr(mcopy, m, M_NOWAIT)) {
1008 /*
1009 * It's probably ok if the pkthdr dup fails (because
1010 * the deep copy of the tag chain failed), but for now
1011 * be conservative and just discard the copy since
1012 * code below may some day want the tags.
1013 */
1014 m_free(mcopy);
1015 mcopy = NULL;
1016 }
1017 if (mcopy != NULL) {
1018 mcopy->m_len = min(ntohs(ip->ip_len), M_TRAILINGSPACE(mcopy));
1019 mcopy->m_pkthdr.len = mcopy->m_len;
1020 m_copydata(m, 0, mcopy->m_len, mtod(mcopy, caddr_t));
1021 }
1022 #ifdef IPSTEALTH
1023 if (V_ipstealth == 0)
1024 #endif
1025 ip->ip_ttl -= IPTTLDEC;
1026 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
1027 if (IPSEC_ENABLED(ipv4)) {
1028 if ((error = IPSEC_FORWARD(ipv4, m)) != 0) {
1029 /* mbuf consumed by IPsec */
1030 RO_NHFREE(&ro);
1031 m_freem(mcopy);
1032 if (error != EINPROGRESS)
1033 IPSTAT_INC(ips_cantforward);
1034 return;
1035 }
1036 /* No IPsec processing required */
1037 }
1038 #endif /* IPSEC */
1039 /*
1040 * If forwarding packet using same interface that it came in on,
1041 * perhaps should send a redirect to sender to shortcut a hop.
1042 * Only send redirect if source is sending directly to us,
1043 * and if packet was not source routed (or has any options).
1044 * Also, don't send redirect if forwarding using a default route
1045 * or a route modified by a redirect.
1046 */
1047 dest.s_addr = 0;
1048 if (!srcrt && V_ipsendredirects &&
1049 ia != NULL && ia->ia_ifp == m->m_pkthdr.rcvif) {
1050 struct nhop_object *nh;
1051
1052 nh = ro.ro_nh;
1053
1054 if (nh != NULL && ((nh->nh_flags & (NHF_REDIRECT|NHF_DEFAULT)) == 0)) {
1055 struct in_ifaddr *nh_ia = (struct in_ifaddr *)(nh->nh_ifa);
1056 u_long src = ntohl(ip->ip_src.s_addr);
1057
1058 if (nh_ia != NULL &&
1059 (src & nh_ia->ia_subnetmask) == nh_ia->ia_subnet) {
1060 /* Router requirements says to only send host redirects */
1061 type = ICMP_REDIRECT;
1062 code = ICMP_REDIRECT_HOST;
1063 if (nh->nh_flags & NHF_GATEWAY) {
1064 if (nh->gw_sa.sa_family == AF_INET)
1065 dest.s_addr = nh->gw4_sa.sin_addr.s_addr;
1066 else /* Do not redirect in case gw is AF_INET6 */
1067 type = 0;
1068 } else
1069 dest.s_addr = ip->ip_dst.s_addr;
1070 }
1071 }
1072 }
1073
1074 error = ip_output(m, NULL, &ro, IP_FORWARDING, NULL, NULL);
1075
1076 if (error == EMSGSIZE && ro.ro_nh)
1077 mtu = ro.ro_nh->nh_mtu;
1078 RO_NHFREE(&ro);
1079
1080 if (error)
1081 IPSTAT_INC(ips_cantforward);
1082 else {
1083 IPSTAT_INC(ips_forward);
1084 if (type)
1085 IPSTAT_INC(ips_redirectsent);
1086 else {
1087 if (mcopy)
1088 m_freem(mcopy);
1089 return;
1090 }
1091 }
1092 if (mcopy == NULL)
1093 return;
1094
1095 switch (error) {
1096 case 0: /* forwarded, but need redirect */
1097 /* type, code set above */
1098 break;
1099
1100 case ENETUNREACH:
1101 case EHOSTUNREACH:
1102 case ENETDOWN:
1103 case EHOSTDOWN:
1104 default:
1105 type = ICMP_UNREACH;
1106 code = ICMP_UNREACH_HOST;
1107 break;
1108
1109 case EMSGSIZE:
1110 type = ICMP_UNREACH;
1111 code = ICMP_UNREACH_NEEDFRAG;
1112 /*
1113 * If the MTU was set before make sure we are below the
1114 * interface MTU.
1115 * If the MTU wasn't set before use the interface mtu or
1116 * fall back to the next smaller mtu step compared to the
1117 * current packet size.
1118 */
1119 if (mtu != 0) {
1120 if (ia != NULL)
1121 mtu = min(mtu, ia->ia_ifp->if_mtu);
1122 } else {
1123 if (ia != NULL)
1124 mtu = ia->ia_ifp->if_mtu;
1125 else
1126 mtu = ip_next_mtu(ntohs(ip->ip_len), 0);
1127 }
1128 IPSTAT_INC(ips_cantfrag);
1129 break;
1130
1131 case ENOBUFS:
1132 case EACCES: /* ipfw denied packet */
1133 m_freem(mcopy);
1134 return;
1135 }
1136 icmp_error(mcopy, type, code, dest.s_addr, mtu);
1137 }
1138
1139 #define CHECK_SO_CT(sp, ct) \
1140 (((sp->so_options & SO_TIMESTAMP) && (sp->so_ts_clock == ct)) ? 1 : 0)
1141
1142 void
ip_savecontrol(struct inpcb * inp,struct mbuf ** mp,struct ip * ip,struct mbuf * m)1143 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
1144 struct mbuf *m)
1145 {
1146 bool stamped;
1147
1148 stamped = false;
1149 if ((inp->inp_socket->so_options & SO_BINTIME) ||
1150 CHECK_SO_CT(inp->inp_socket, SO_TS_BINTIME)) {
1151 struct bintime boottimebin, bt;
1152 struct timespec ts1;
1153
1154 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1155 M_TSTMP)) {
1156 mbuf_tstmp2timespec(m, &ts1);
1157 timespec2bintime(&ts1, &bt);
1158 getboottimebin(&boottimebin);
1159 bintime_add(&bt, &boottimebin);
1160 } else {
1161 bintime(&bt);
1162 }
1163 *mp = sbcreatecontrol(&bt, sizeof(bt), SCM_BINTIME,
1164 SOL_SOCKET, M_NOWAIT);
1165 if (*mp != NULL) {
1166 mp = &(*mp)->m_next;
1167 stamped = true;
1168 }
1169 }
1170 if (CHECK_SO_CT(inp->inp_socket, SO_TS_REALTIME_MICRO)) {
1171 struct bintime boottimebin, bt1;
1172 struct timespec ts1;
1173 struct timeval tv;
1174
1175 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1176 M_TSTMP)) {
1177 mbuf_tstmp2timespec(m, &ts1);
1178 timespec2bintime(&ts1, &bt1);
1179 getboottimebin(&boottimebin);
1180 bintime_add(&bt1, &boottimebin);
1181 bintime2timeval(&bt1, &tv);
1182 } else {
1183 microtime(&tv);
1184 }
1185 *mp = sbcreatecontrol((caddr_t)&tv, sizeof(tv), SCM_TIMESTAMP,
1186 SOL_SOCKET, M_NOWAIT);
1187 if (*mp != NULL) {
1188 mp = &(*mp)->m_next;
1189 stamped = true;
1190 }
1191 } else if (CHECK_SO_CT(inp->inp_socket, SO_TS_REALTIME)) {
1192 struct bintime boottimebin;
1193 struct timespec ts, ts1;
1194
1195 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1196 M_TSTMP)) {
1197 mbuf_tstmp2timespec(m, &ts);
1198 getboottimebin(&boottimebin);
1199 bintime2timespec(&boottimebin, &ts1);
1200 timespecadd(&ts, &ts1, &ts);
1201 } else {
1202 nanotime(&ts);
1203 }
1204 *mp = sbcreatecontrol(&ts, sizeof(ts), SCM_REALTIME,
1205 SOL_SOCKET, M_NOWAIT);
1206 if (*mp != NULL) {
1207 mp = &(*mp)->m_next;
1208 stamped = true;
1209 }
1210 } else if (CHECK_SO_CT(inp->inp_socket, SO_TS_MONOTONIC)) {
1211 struct timespec ts;
1212
1213 if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1214 M_TSTMP))
1215 mbuf_tstmp2timespec(m, &ts);
1216 else
1217 nanouptime(&ts);
1218 *mp = sbcreatecontrol(&ts, sizeof(ts), SCM_MONOTONIC,
1219 SOL_SOCKET, M_NOWAIT);
1220 if (*mp != NULL) {
1221 mp = &(*mp)->m_next;
1222 stamped = true;
1223 }
1224 }
1225 if (stamped && (m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1226 M_TSTMP)) {
1227 struct sock_timestamp_info sti;
1228
1229 bzero(&sti, sizeof(sti));
1230 sti.st_info_flags = ST_INFO_HW;
1231 if ((m->m_flags & M_TSTMP_HPREC) != 0)
1232 sti.st_info_flags |= ST_INFO_HW_HPREC;
1233 *mp = sbcreatecontrol(&sti, sizeof(sti), SCM_TIME_INFO,
1234 SOL_SOCKET, M_NOWAIT);
1235 if (*mp != NULL)
1236 mp = &(*mp)->m_next;
1237 }
1238 if (inp->inp_flags & INP_RECVDSTADDR) {
1239 *mp = sbcreatecontrol(&ip->ip_dst, sizeof(struct in_addr),
1240 IP_RECVDSTADDR, IPPROTO_IP, M_NOWAIT);
1241 if (*mp)
1242 mp = &(*mp)->m_next;
1243 }
1244 if (inp->inp_flags & INP_RECVTTL) {
1245 *mp = sbcreatecontrol(&ip->ip_ttl, sizeof(u_char), IP_RECVTTL,
1246 IPPROTO_IP, M_NOWAIT);
1247 if (*mp)
1248 mp = &(*mp)->m_next;
1249 }
1250 #ifdef notyet
1251 /* XXX
1252 * Moving these out of udp_input() made them even more broken
1253 * than they already were.
1254 */
1255 /* options were tossed already */
1256 if (inp->inp_flags & INP_RECVOPTS) {
1257 *mp = sbcreatecontrol(opts_deleted_above,
1258 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP, M_NOWAIT);
1259 if (*mp)
1260 mp = &(*mp)->m_next;
1261 }
1262 /* ip_srcroute doesn't do what we want here, need to fix */
1263 if (inp->inp_flags & INP_RECVRETOPTS) {
1264 *mp = sbcreatecontrol(ip_srcroute(m), sizeof(struct in_addr),
1265 IP_RECVRETOPTS, IPPROTO_IP, M_NOWAIT);
1266 if (*mp)
1267 mp = &(*mp)->m_next;
1268 }
1269 #endif
1270 if (inp->inp_flags & INP_RECVIF) {
1271 struct ifnet *ifp;
1272 struct sdlbuf {
1273 struct sockaddr_dl sdl;
1274 u_char pad[32];
1275 } sdlbuf;
1276 struct sockaddr_dl *sdp;
1277 struct sockaddr_dl *sdl2 = &sdlbuf.sdl;
1278
1279 if ((ifp = m->m_pkthdr.rcvif)) {
1280 sdp = (struct sockaddr_dl *)ifp->if_addr->ifa_addr;
1281 /*
1282 * Change our mind and don't try copy.
1283 */
1284 if (sdp->sdl_family != AF_LINK ||
1285 sdp->sdl_len > sizeof(sdlbuf)) {
1286 goto makedummy;
1287 }
1288 bcopy(sdp, sdl2, sdp->sdl_len);
1289 } else {
1290 makedummy:
1291 sdl2->sdl_len =
1292 offsetof(struct sockaddr_dl, sdl_data[0]);
1293 sdl2->sdl_family = AF_LINK;
1294 sdl2->sdl_index = 0;
1295 sdl2->sdl_nlen = sdl2->sdl_alen = sdl2->sdl_slen = 0;
1296 }
1297 *mp = sbcreatecontrol(sdl2, sdl2->sdl_len, IP_RECVIF,
1298 IPPROTO_IP, M_NOWAIT);
1299 if (*mp)
1300 mp = &(*mp)->m_next;
1301 }
1302 if (inp->inp_flags & INP_RECVTOS) {
1303 *mp = sbcreatecontrol(&ip->ip_tos, sizeof(u_char), IP_RECVTOS,
1304 IPPROTO_IP, M_NOWAIT);
1305 if (*mp)
1306 mp = &(*mp)->m_next;
1307 }
1308
1309 if (inp->inp_flags2 & INP_RECVFLOWID) {
1310 uint32_t flowid, flow_type;
1311
1312 flowid = m->m_pkthdr.flowid;
1313 flow_type = M_HASHTYPE_GET(m);
1314
1315 /*
1316 * XXX should handle the failure of one or the
1317 * other - don't populate both?
1318 */
1319 *mp = sbcreatecontrol(&flowid, sizeof(uint32_t), IP_FLOWID,
1320 IPPROTO_IP, M_NOWAIT);
1321 if (*mp)
1322 mp = &(*mp)->m_next;
1323 *mp = sbcreatecontrol(&flow_type, sizeof(uint32_t),
1324 IP_FLOWTYPE, IPPROTO_IP, M_NOWAIT);
1325 if (*mp)
1326 mp = &(*mp)->m_next;
1327 }
1328
1329 #ifdef RSS
1330 if (inp->inp_flags2 & INP_RECVRSSBUCKETID) {
1331 uint32_t flowid, flow_type;
1332 uint32_t rss_bucketid;
1333
1334 flowid = m->m_pkthdr.flowid;
1335 flow_type = M_HASHTYPE_GET(m);
1336
1337 if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) {
1338 *mp = sbcreatecontrol(&rss_bucketid, sizeof(uint32_t),
1339 IP_RSSBUCKETID, IPPROTO_IP, M_NOWAIT);
1340 if (*mp)
1341 mp = &(*mp)->m_next;
1342 }
1343 }
1344 #endif
1345 }
1346
1347 /*
1348 * XXXRW: Multicast routing code in ip_mroute.c is generally MPSAFE, but the
1349 * ip_rsvp and ip_rsvp_on variables need to be interlocked with rsvp_on
1350 * locking. This code remains in ip_input.c as ip_mroute.c is optionally
1351 * compiled.
1352 */
1353 VNET_DEFINE_STATIC(int, ip_rsvp_on);
1354 VNET_DEFINE(struct socket *, ip_rsvpd);
1355
1356 #define V_ip_rsvp_on VNET(ip_rsvp_on)
1357
1358 int
ip_rsvp_init(struct socket * so)1359 ip_rsvp_init(struct socket *so)
1360 {
1361
1362 if (V_ip_rsvpd != NULL)
1363 return EADDRINUSE;
1364
1365 V_ip_rsvpd = so;
1366 /*
1367 * This may seem silly, but we need to be sure we don't over-increment
1368 * the RSVP counter, in case something slips up.
1369 */
1370 if (!V_ip_rsvp_on) {
1371 V_ip_rsvp_on = 1;
1372 V_rsvp_on++;
1373 }
1374
1375 return 0;
1376 }
1377
1378 int
ip_rsvp_done(void)1379 ip_rsvp_done(void)
1380 {
1381
1382 V_ip_rsvpd = NULL;
1383 /*
1384 * This may seem silly, but we need to be sure we don't over-decrement
1385 * the RSVP counter, in case something slips up.
1386 */
1387 if (V_ip_rsvp_on) {
1388 V_ip_rsvp_on = 0;
1389 V_rsvp_on--;
1390 }
1391 return 0;
1392 }
1393
1394 int
rsvp_input(struct mbuf ** mp,int * offp,int proto)1395 rsvp_input(struct mbuf **mp, int *offp, int proto)
1396 {
1397 struct mbuf *m;
1398
1399 m = *mp;
1400 *mp = NULL;
1401
1402 if (rsvp_input_p) { /* call the real one if loaded */
1403 *mp = m;
1404 rsvp_input_p(mp, offp, proto);
1405 return (IPPROTO_DONE);
1406 }
1407
1408 /* Can still get packets with rsvp_on = 0 if there is a local member
1409 * of the group to which the RSVP packet is addressed. But in this
1410 * case we want to throw the packet away.
1411 */
1412
1413 if (!V_rsvp_on) {
1414 m_freem(m);
1415 return (IPPROTO_DONE);
1416 }
1417
1418 if (V_ip_rsvpd != NULL) {
1419 *mp = m;
1420 rip_input(mp, offp, proto);
1421 return (IPPROTO_DONE);
1422 }
1423 /* Drop the packet */
1424 m_freem(m);
1425 return (IPPROTO_DONE);
1426 }
1427