1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1988, 1993
5 * The Regents of the University of California.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)raw_ip.c 8.7 (Berkeley) 5/15/95
33 */
34
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37
38 #include "opt_inet.h"
39 #include "opt_inet6.h"
40 #include "opt_ipsec.h"
41 #include "opt_route.h"
42
43 #include <sys/param.h>
44 #include <sys/jail.h>
45 #include <sys/kernel.h>
46 #include <sys/eventhandler.h>
47 #include <sys/lock.h>
48 #include <sys/malloc.h>
49 #include <sys/mbuf.h>
50 #include <sys/priv.h>
51 #include <sys/proc.h>
52 #include <sys/protosw.h>
53 #include <sys/rmlock.h>
54 #include <sys/rwlock.h>
55 #include <sys/signalvar.h>
56 #include <sys/socket.h>
57 #include <sys/socketvar.h>
58 #include <sys/sx.h>
59 #include <sys/sysctl.h>
60 #include <sys/systm.h>
61
62 #include <vm/uma.h>
63
64 #include <net/if.h>
65 #include <net/if_var.h>
66 #include <net/route.h>
67 #include <net/route/route_ctl.h>
68 #include <net/vnet.h>
69
70 #include <netinet/in.h>
71 #include <netinet/in_systm.h>
72 #include <netinet/in_fib.h>
73 #include <netinet/in_pcb.h>
74 #include <netinet/in_var.h>
75 #include <netinet/if_ether.h>
76 #include <netinet/ip.h>
77 #include <netinet/ip_var.h>
78 #include <netinet/ip_mroute.h>
79 #include <netinet/ip_icmp.h>
80
81 #include <netipsec/ipsec_support.h>
82
83 #include <machine/stdarg.h>
84 #include <security/mac/mac_framework.h>
85
86 VNET_DEFINE(int, ip_defttl) = IPDEFTTL;
87 SYSCTL_INT(_net_inet_ip, IPCTL_DEFTTL, ttl, CTLFLAG_VNET | CTLFLAG_RW,
88 &VNET_NAME(ip_defttl), 0,
89 "Maximum TTL on IP packets");
90
91 VNET_DEFINE(struct inpcbhead, ripcb);
92 VNET_DEFINE(struct inpcbinfo, ripcbinfo);
93
94 #define V_ripcb VNET(ripcb)
95 #define V_ripcbinfo VNET(ripcbinfo)
96
97 /*
98 * Control and data hooks for ipfw, dummynet, divert and so on.
99 * The data hooks are not used here but it is convenient
100 * to keep them all in one place.
101 */
102 VNET_DEFINE(ip_fw_chk_ptr_t, ip_fw_chk_ptr) = NULL;
103 VNET_DEFINE(ip_fw_ctl_ptr_t, ip_fw_ctl_ptr) = NULL;
104
105 int (*ip_dn_ctl_ptr)(struct sockopt *);
106 int (*ip_dn_io_ptr)(struct mbuf **, struct ip_fw_args *);
107 void (*ip_divert_ptr)(struct mbuf *, bool);
108 int (*ng_ipfw_input_p)(struct mbuf **, struct ip_fw_args *, bool);
109
110 #ifdef INET
111 /*
112 * Hooks for multicast routing. They all default to NULL, so leave them not
113 * initialized and rely on BSS being set to 0.
114 */
115
116 /*
117 * The socket used to communicate with the multicast routing daemon.
118 */
119 VNET_DEFINE(struct socket *, ip_mrouter);
120
121 /*
122 * The various mrouter and rsvp functions.
123 */
124 int (*ip_mrouter_set)(struct socket *, struct sockopt *);
125 int (*ip_mrouter_get)(struct socket *, struct sockopt *);
126 int (*ip_mrouter_done)(void);
127 int (*ip_mforward)(struct ip *, struct ifnet *, struct mbuf *,
128 struct ip_moptions *);
129 int (*mrt_ioctl)(u_long, caddr_t, int);
130 int (*legal_vif_num)(int);
131 u_long (*ip_mcast_src)(int);
132
133 int (*rsvp_input_p)(struct mbuf **, int *, int);
134 int (*ip_rsvp_vif)(struct socket *, struct sockopt *);
135 void (*ip_rsvp_force_done)(struct socket *);
136 #endif /* INET */
137
138 extern struct protosw inetsw[];
139
140 u_long rip_sendspace = 9216;
141 SYSCTL_ULONG(_net_inet_raw, OID_AUTO, maxdgram, CTLFLAG_RW,
142 &rip_sendspace, 0, "Maximum outgoing raw IP datagram size");
143
144 u_long rip_recvspace = 9216;
145 SYSCTL_ULONG(_net_inet_raw, OID_AUTO, recvspace, CTLFLAG_RW,
146 &rip_recvspace, 0, "Maximum space for incoming raw IP datagrams");
147
148 /*
149 * Hash functions
150 */
151
152 #define INP_PCBHASH_RAW_SIZE 256
153 #define INP_PCBHASH_RAW(proto, laddr, faddr, mask) \
154 (((proto) + (laddr) + (faddr)) % (mask) + 1)
155
156 #ifdef INET
157 static void
rip_inshash(struct inpcb * inp)158 rip_inshash(struct inpcb *inp)
159 {
160 struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
161 struct inpcbhead *pcbhash;
162 int hash;
163
164 INP_INFO_WLOCK_ASSERT(pcbinfo);
165 INP_WLOCK_ASSERT(inp);
166
167 if (inp->inp_ip_p != 0 &&
168 inp->inp_laddr.s_addr != INADDR_ANY &&
169 inp->inp_faddr.s_addr != INADDR_ANY) {
170 hash = INP_PCBHASH_RAW(inp->inp_ip_p, inp->inp_laddr.s_addr,
171 inp->inp_faddr.s_addr, pcbinfo->ipi_hashmask);
172 } else
173 hash = 0;
174 pcbhash = &pcbinfo->ipi_hashbase[hash];
175 CK_LIST_INSERT_HEAD(pcbhash, inp, inp_hash);
176 }
177
178 static void
rip_delhash(struct inpcb * inp)179 rip_delhash(struct inpcb *inp)
180 {
181
182 INP_INFO_WLOCK_ASSERT(inp->inp_pcbinfo);
183 INP_WLOCK_ASSERT(inp);
184
185 CK_LIST_REMOVE(inp, inp_hash);
186 }
187 #endif /* INET */
188
189 /*
190 * Raw interface to IP protocol.
191 */
192
193 /*
194 * Initialize raw connection block q.
195 */
196 static void
rip_zone_change(void * tag)197 rip_zone_change(void *tag)
198 {
199
200 uma_zone_set_max(V_ripcbinfo.ipi_zone, maxsockets);
201 }
202
203 static int
rip_inpcb_init(void * mem,int size,int flags)204 rip_inpcb_init(void *mem, int size, int flags)
205 {
206 struct inpcb *inp = mem;
207
208 INP_LOCK_INIT(inp, "inp", "rawinp");
209 return (0);
210 }
211
212 void
rip_init(void)213 rip_init(void)
214 {
215
216 in_pcbinfo_init(&V_ripcbinfo, "rip", &V_ripcb, INP_PCBHASH_RAW_SIZE,
217 1, "ripcb", rip_inpcb_init, IPI_HASHFIELDS_NONE);
218 EVENTHANDLER_REGISTER(maxsockets_change, rip_zone_change, NULL,
219 EVENTHANDLER_PRI_ANY);
220 }
221
222 #ifdef VIMAGE
223 static void
rip_destroy(void * unused __unused)224 rip_destroy(void *unused __unused)
225 {
226
227 in_pcbinfo_destroy(&V_ripcbinfo);
228 }
229 VNET_SYSUNINIT(raw_ip, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, rip_destroy, NULL);
230 #endif
231
232 #ifdef INET
233 static int
rip_append(struct inpcb * last,struct ip * ip,struct mbuf * n,struct sockaddr_in * ripsrc)234 rip_append(struct inpcb *last, struct ip *ip, struct mbuf *n,
235 struct sockaddr_in *ripsrc)
236 {
237 int policyfail = 0;
238
239 INP_LOCK_ASSERT(last);
240
241 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
242 /* check AH/ESP integrity. */
243 if (IPSEC_ENABLED(ipv4)) {
244 if (IPSEC_CHECK_POLICY(ipv4, n, last) != 0)
245 policyfail = 1;
246 }
247 #endif /* IPSEC */
248 #ifdef MAC
249 if (!policyfail && mac_inpcb_check_deliver(last, n) != 0)
250 policyfail = 1;
251 #endif
252 /* Check the minimum TTL for socket. */
253 if (last->inp_ip_minttl && last->inp_ip_minttl > ip->ip_ttl)
254 policyfail = 1;
255 if (!policyfail) {
256 struct mbuf *opts = NULL;
257 struct socket *so;
258
259 so = last->inp_socket;
260 if ((last->inp_flags & INP_CONTROLOPTS) ||
261 (so->so_options & (SO_TIMESTAMP | SO_BINTIME)))
262 ip_savecontrol(last, &opts, ip, n);
263 SOCKBUF_LOCK(&so->so_rcv);
264 if (sbappendaddr_locked(&so->so_rcv,
265 (struct sockaddr *)ripsrc, n, opts) == 0) {
266 soroverflow_locked(so);
267 m_freem(n);
268 if (opts)
269 m_freem(opts);
270 } else
271 sorwakeup_locked(so);
272 } else
273 m_freem(n);
274 return (policyfail);
275 }
276
277 /*
278 * Setup generic address and protocol structures for raw_input routine, then
279 * pass them along with mbuf chain.
280 */
281 int
rip_input(struct mbuf ** mp,int * offp,int proto)282 rip_input(struct mbuf **mp, int *offp, int proto)
283 {
284 struct ifnet *ifp;
285 struct mbuf *m = *mp;
286 struct ip *ip = mtod(m, struct ip *);
287 struct inpcb *inp, *last;
288 struct sockaddr_in ripsrc;
289 int hash;
290
291 NET_EPOCH_ASSERT();
292
293 *mp = NULL;
294
295 bzero(&ripsrc, sizeof(ripsrc));
296 ripsrc.sin_len = sizeof(ripsrc);
297 ripsrc.sin_family = AF_INET;
298 ripsrc.sin_addr = ip->ip_src;
299 last = NULL;
300
301 ifp = m->m_pkthdr.rcvif;
302
303 hash = INP_PCBHASH_RAW(proto, ip->ip_src.s_addr,
304 ip->ip_dst.s_addr, V_ripcbinfo.ipi_hashmask);
305 CK_LIST_FOREACH(inp, &V_ripcbinfo.ipi_hashbase[hash], inp_hash) {
306 if (inp->inp_ip_p != proto)
307 continue;
308 #ifdef INET6
309 /* XXX inp locking */
310 if ((inp->inp_vflag & INP_IPV4) == 0)
311 continue;
312 #endif
313 if (inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
314 continue;
315 if (inp->inp_faddr.s_addr != ip->ip_src.s_addr)
316 continue;
317 if (last != NULL) {
318 struct mbuf *n;
319
320 n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
321 if (n != NULL)
322 (void) rip_append(last, ip, n, &ripsrc);
323 /* XXX count dropped packet */
324 INP_RUNLOCK(last);
325 last = NULL;
326 }
327 INP_RLOCK(inp);
328 if (__predict_false(inp->inp_flags2 & INP_FREED))
329 goto skip_1;
330 if (jailed_without_vnet(inp->inp_cred)) {
331 /*
332 * XXX: If faddr was bound to multicast group,
333 * jailed raw socket will drop datagram.
334 */
335 if (prison_check_ip4(inp->inp_cred, &ip->ip_dst) != 0)
336 goto skip_1;
337 }
338 last = inp;
339 continue;
340 skip_1:
341 INP_RUNLOCK(inp);
342 }
343 CK_LIST_FOREACH(inp, &V_ripcbinfo.ipi_hashbase[0], inp_hash) {
344 if (inp->inp_ip_p && inp->inp_ip_p != proto)
345 continue;
346 #ifdef INET6
347 /* XXX inp locking */
348 if ((inp->inp_vflag & INP_IPV4) == 0)
349 continue;
350 #endif
351 if (!in_nullhost(inp->inp_laddr) &&
352 !in_hosteq(inp->inp_laddr, ip->ip_dst))
353 continue;
354 if (!in_nullhost(inp->inp_faddr) &&
355 !in_hosteq(inp->inp_faddr, ip->ip_src))
356 continue;
357 if (last != NULL) {
358 struct mbuf *n;
359
360 n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
361 if (n != NULL)
362 (void) rip_append(last, ip, n, &ripsrc);
363 /* XXX count dropped packet */
364 INP_RUNLOCK(last);
365 last = NULL;
366 }
367 INP_RLOCK(inp);
368 if (__predict_false(inp->inp_flags2 & INP_FREED))
369 goto skip_2;
370 if (jailed_without_vnet(inp->inp_cred)) {
371 /*
372 * Allow raw socket in jail to receive multicast;
373 * assume process had PRIV_NETINET_RAW at attach,
374 * and fall through into normal filter path if so.
375 */
376 if (!IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
377 prison_check_ip4(inp->inp_cred, &ip->ip_dst) != 0)
378 goto skip_2;
379 }
380 /*
381 * If this raw socket has multicast state, and we
382 * have received a multicast, check if this socket
383 * should receive it, as multicast filtering is now
384 * the responsibility of the transport layer.
385 */
386 if (inp->inp_moptions != NULL &&
387 IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
388 /*
389 * If the incoming datagram is for IGMP, allow it
390 * through unconditionally to the raw socket.
391 *
392 * In the case of IGMPv2, we may not have explicitly
393 * joined the group, and may have set IFF_ALLMULTI
394 * on the interface. imo_multi_filter() may discard
395 * control traffic we actually need to see.
396 *
397 * Userland multicast routing daemons should continue
398 * filter the control traffic appropriately.
399 */
400 int blocked;
401
402 blocked = MCAST_PASS;
403 if (proto != IPPROTO_IGMP) {
404 struct sockaddr_in group;
405
406 bzero(&group, sizeof(struct sockaddr_in));
407 group.sin_len = sizeof(struct sockaddr_in);
408 group.sin_family = AF_INET;
409 group.sin_addr = ip->ip_dst;
410
411 blocked = imo_multi_filter(inp->inp_moptions,
412 ifp,
413 (struct sockaddr *)&group,
414 (struct sockaddr *)&ripsrc);
415 }
416
417 if (blocked != MCAST_PASS) {
418 IPSTAT_INC(ips_notmember);
419 goto skip_2;
420 }
421 }
422 last = inp;
423 continue;
424 skip_2:
425 INP_RUNLOCK(inp);
426 }
427 if (last != NULL) {
428 if (rip_append(last, ip, m, &ripsrc) != 0)
429 IPSTAT_INC(ips_delivered);
430 INP_RUNLOCK(last);
431 } else {
432 if (inetsw[ip_protox[ip->ip_p]].pr_input == rip_input) {
433 IPSTAT_INC(ips_noproto);
434 IPSTAT_DEC(ips_delivered);
435 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PROTOCOL, 0, 0);
436 } else {
437 m_freem(m);
438 }
439 }
440 return (IPPROTO_DONE);
441 }
442
443 /*
444 * Generate IP header and pass packet to ip_output. Tack on options user may
445 * have setup with control call.
446 */
447 int
rip_output(struct mbuf * m,struct socket * so,...)448 rip_output(struct mbuf *m, struct socket *so, ...)
449 {
450 struct epoch_tracker et;
451 struct ip *ip;
452 int error;
453 struct inpcb *inp = sotoinpcb(so);
454 va_list ap;
455 u_long dst;
456 int flags = ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0) |
457 IP_ALLOWBROADCAST;
458 int cnt, hlen;
459 u_char opttype, optlen, *cp;
460
461 va_start(ap, so);
462 dst = va_arg(ap, u_long);
463 va_end(ap);
464
465 /*
466 * If the user handed us a complete IP packet, use it. Otherwise,
467 * allocate an mbuf for a header and fill it in.
468 */
469 if ((inp->inp_flags & INP_HDRINCL) == 0) {
470 if (m->m_pkthdr.len + sizeof(struct ip) > IP_MAXPACKET) {
471 m_freem(m);
472 return(EMSGSIZE);
473 }
474 M_PREPEND(m, sizeof(struct ip), M_NOWAIT);
475 if (m == NULL)
476 return(ENOBUFS);
477
478 INP_RLOCK(inp);
479 ip = mtod(m, struct ip *);
480 ip->ip_tos = inp->inp_ip_tos;
481 if (inp->inp_flags & INP_DONTFRAG)
482 ip->ip_off = htons(IP_DF);
483 else
484 ip->ip_off = htons(0);
485 ip->ip_p = inp->inp_ip_p;
486 ip->ip_len = htons(m->m_pkthdr.len);
487 ip->ip_src = inp->inp_laddr;
488 ip->ip_dst.s_addr = dst;
489 #ifdef ROUTE_MPATH
490 if (CALC_FLOWID_OUTBOUND) {
491 uint32_t hash_type, hash_val;
492
493 hash_val = fib4_calc_software_hash(ip->ip_src,
494 ip->ip_dst, 0, 0, ip->ip_p, &hash_type);
495 m->m_pkthdr.flowid = hash_val;
496 M_HASHTYPE_SET(m, hash_type);
497 flags |= IP_NODEFAULTFLOWID;
498 }
499 #endif
500 if (jailed(inp->inp_cred)) {
501 /*
502 * prison_local_ip4() would be good enough but would
503 * let a source of INADDR_ANY pass, which we do not
504 * want to see from jails.
505 */
506 if (ip->ip_src.s_addr == INADDR_ANY) {
507 NET_EPOCH_ENTER(et);
508 error = in_pcbladdr(inp, &ip->ip_dst,
509 &ip->ip_src, inp->inp_cred);
510 NET_EPOCH_EXIT(et);
511 } else {
512 error = prison_local_ip4(inp->inp_cred,
513 &ip->ip_src);
514 }
515 if (error != 0) {
516 INP_RUNLOCK(inp);
517 m_freem(m);
518 return (error);
519 }
520 }
521 ip->ip_ttl = inp->inp_ip_ttl;
522 } else {
523 if (m->m_pkthdr.len > IP_MAXPACKET) {
524 m_freem(m);
525 return (EMSGSIZE);
526 }
527 if (m->m_pkthdr.len < sizeof(*ip)) {
528 m_freem(m);
529 return (EINVAL);
530 }
531 m = m_pullup(m, sizeof(*ip));
532 if (m == NULL)
533 return (ENOMEM);
534 ip = mtod(m, struct ip *);
535 hlen = ip->ip_hl << 2;
536 if (m->m_len < hlen) {
537 m = m_pullup(m, hlen);
538 if (m == NULL)
539 return (EINVAL);
540 ip = mtod(m, struct ip *);
541 }
542 #ifdef ROUTE_MPATH
543 if (CALC_FLOWID_OUTBOUND) {
544 uint32_t hash_type, hash_val;
545
546 hash_val = fib4_calc_software_hash(ip->ip_dst,
547 ip->ip_src, 0, 0, ip->ip_p, &hash_type);
548 m->m_pkthdr.flowid = hash_val;
549 M_HASHTYPE_SET(m, hash_type);
550 flags |= IP_NODEFAULTFLOWID;
551 }
552 #endif
553 INP_RLOCK(inp);
554 /*
555 * Don't allow both user specified and setsockopt options,
556 * and don't allow packet length sizes that will crash.
557 */
558 if ((hlen < sizeof (*ip))
559 || ((hlen > sizeof (*ip)) && inp->inp_options)
560 || (ntohs(ip->ip_len) != m->m_pkthdr.len)) {
561 INP_RUNLOCK(inp);
562 m_freem(m);
563 return (EINVAL);
564 }
565 error = prison_check_ip4(inp->inp_cred, &ip->ip_src);
566 if (error != 0) {
567 INP_RUNLOCK(inp);
568 m_freem(m);
569 return (error);
570 }
571 /*
572 * Don't allow IP options which do not have the required
573 * structure as specified in section 3.1 of RFC 791 on
574 * pages 15-23.
575 */
576 cp = (u_char *)(ip + 1);
577 cnt = hlen - sizeof (struct ip);
578 for (; cnt > 0; cnt -= optlen, cp += optlen) {
579 opttype = cp[IPOPT_OPTVAL];
580 if (opttype == IPOPT_EOL)
581 break;
582 if (opttype == IPOPT_NOP) {
583 optlen = 1;
584 continue;
585 }
586 if (cnt < IPOPT_OLEN + sizeof(u_char)) {
587 INP_RUNLOCK(inp);
588 m_freem(m);
589 return (EINVAL);
590 }
591 optlen = cp[IPOPT_OLEN];
592 if (optlen < IPOPT_OLEN + sizeof(u_char) ||
593 optlen > cnt) {
594 INP_RUNLOCK(inp);
595 m_freem(m);
596 return (EINVAL);
597 }
598 }
599 /*
600 * This doesn't allow application to specify ID of zero,
601 * but we got this limitation from the beginning of history.
602 */
603 if (ip->ip_id == 0)
604 ip_fillid(ip);
605
606 /*
607 * XXX prevent ip_output from overwriting header fields.
608 */
609 flags |= IP_RAWOUTPUT;
610 IPSTAT_INC(ips_rawout);
611 }
612
613 if (inp->inp_flags & INP_ONESBCAST)
614 flags |= IP_SENDONES;
615
616 #ifdef MAC
617 mac_inpcb_create_mbuf(inp, m);
618 #endif
619
620 NET_EPOCH_ENTER(et);
621 error = ip_output(m, inp->inp_options, NULL, flags,
622 inp->inp_moptions, inp);
623 NET_EPOCH_EXIT(et);
624 INP_RUNLOCK(inp);
625 return (error);
626 }
627
628 /*
629 * Raw IP socket option processing.
630 *
631 * IMPORTANT NOTE regarding access control: Traditionally, raw sockets could
632 * only be created by a privileged process, and as such, socket option
633 * operations to manage system properties on any raw socket were allowed to
634 * take place without explicit additional access control checks. However,
635 * raw sockets can now also be created in jail(), and therefore explicit
636 * checks are now required. Likewise, raw sockets can be used by a process
637 * after it gives up privilege, so some caution is required. For options
638 * passed down to the IP layer via ip_ctloutput(), checks are assumed to be
639 * performed in ip_ctloutput() and therefore no check occurs here.
640 * Unilaterally checking priv_check() here breaks normal IP socket option
641 * operations on raw sockets.
642 *
643 * When adding new socket options here, make sure to add access control
644 * checks here as necessary.
645 *
646 * XXX-BZ inp locking?
647 */
648 int
rip_ctloutput(struct socket * so,struct sockopt * sopt)649 rip_ctloutput(struct socket *so, struct sockopt *sopt)
650 {
651 struct inpcb *inp = sotoinpcb(so);
652 int error, optval;
653
654 if (sopt->sopt_level != IPPROTO_IP) {
655 if ((sopt->sopt_level == SOL_SOCKET) &&
656 (sopt->sopt_name == SO_SETFIB)) {
657 inp->inp_inc.inc_fibnum = so->so_fibnum;
658 return (0);
659 }
660 return (EINVAL);
661 }
662
663 error = 0;
664 switch (sopt->sopt_dir) {
665 case SOPT_GET:
666 switch (sopt->sopt_name) {
667 case IP_HDRINCL:
668 optval = inp->inp_flags & INP_HDRINCL;
669 error = sooptcopyout(sopt, &optval, sizeof optval);
670 break;
671
672 case IP_FW3: /* generic ipfw v.3 functions */
673 case IP_FW_ADD: /* ADD actually returns the body... */
674 case IP_FW_GET:
675 case IP_FW_TABLE_GETSIZE:
676 case IP_FW_TABLE_LIST:
677 case IP_FW_NAT_GET_CONFIG:
678 case IP_FW_NAT_GET_LOG:
679 if (V_ip_fw_ctl_ptr != NULL)
680 error = V_ip_fw_ctl_ptr(sopt);
681 else
682 error = ENOPROTOOPT;
683 break;
684
685 case IP_DUMMYNET3: /* generic dummynet v.3 functions */
686 case IP_DUMMYNET_GET:
687 if (ip_dn_ctl_ptr != NULL)
688 error = ip_dn_ctl_ptr(sopt);
689 else
690 error = ENOPROTOOPT;
691 break ;
692
693 case MRT_INIT:
694 case MRT_DONE:
695 case MRT_ADD_VIF:
696 case MRT_DEL_VIF:
697 case MRT_ADD_MFC:
698 case MRT_DEL_MFC:
699 case MRT_VERSION:
700 case MRT_ASSERT:
701 case MRT_API_SUPPORT:
702 case MRT_API_CONFIG:
703 case MRT_ADD_BW_UPCALL:
704 case MRT_DEL_BW_UPCALL:
705 error = priv_check(curthread, PRIV_NETINET_MROUTE);
706 if (error != 0)
707 return (error);
708 error = ip_mrouter_get ? ip_mrouter_get(so, sopt) :
709 EOPNOTSUPP;
710 break;
711
712 default:
713 error = ip_ctloutput(so, sopt);
714 break;
715 }
716 break;
717
718 case SOPT_SET:
719 switch (sopt->sopt_name) {
720 case IP_HDRINCL:
721 error = sooptcopyin(sopt, &optval, sizeof optval,
722 sizeof optval);
723 if (error)
724 break;
725 if (optval)
726 inp->inp_flags |= INP_HDRINCL;
727 else
728 inp->inp_flags &= ~INP_HDRINCL;
729 break;
730
731 case IP_FW3: /* generic ipfw v.3 functions */
732 case IP_FW_ADD:
733 case IP_FW_DEL:
734 case IP_FW_FLUSH:
735 case IP_FW_ZERO:
736 case IP_FW_RESETLOG:
737 case IP_FW_TABLE_ADD:
738 case IP_FW_TABLE_DEL:
739 case IP_FW_TABLE_FLUSH:
740 case IP_FW_NAT_CFG:
741 case IP_FW_NAT_DEL:
742 if (V_ip_fw_ctl_ptr != NULL)
743 error = V_ip_fw_ctl_ptr(sopt);
744 else
745 error = ENOPROTOOPT;
746 break;
747
748 case IP_DUMMYNET3: /* generic dummynet v.3 functions */
749 case IP_DUMMYNET_CONFIGURE:
750 case IP_DUMMYNET_DEL:
751 case IP_DUMMYNET_FLUSH:
752 if (ip_dn_ctl_ptr != NULL)
753 error = ip_dn_ctl_ptr(sopt);
754 else
755 error = ENOPROTOOPT ;
756 break ;
757
758 case IP_RSVP_ON:
759 error = priv_check(curthread, PRIV_NETINET_MROUTE);
760 if (error != 0)
761 return (error);
762 error = ip_rsvp_init(so);
763 break;
764
765 case IP_RSVP_OFF:
766 error = priv_check(curthread, PRIV_NETINET_MROUTE);
767 if (error != 0)
768 return (error);
769 error = ip_rsvp_done();
770 break;
771
772 case IP_RSVP_VIF_ON:
773 case IP_RSVP_VIF_OFF:
774 error = priv_check(curthread, PRIV_NETINET_MROUTE);
775 if (error != 0)
776 return (error);
777 error = ip_rsvp_vif ?
778 ip_rsvp_vif(so, sopt) : EINVAL;
779 break;
780
781 case MRT_INIT:
782 case MRT_DONE:
783 case MRT_ADD_VIF:
784 case MRT_DEL_VIF:
785 case MRT_ADD_MFC:
786 case MRT_DEL_MFC:
787 case MRT_VERSION:
788 case MRT_ASSERT:
789 case MRT_API_SUPPORT:
790 case MRT_API_CONFIG:
791 case MRT_ADD_BW_UPCALL:
792 case MRT_DEL_BW_UPCALL:
793 error = priv_check(curthread, PRIV_NETINET_MROUTE);
794 if (error != 0)
795 return (error);
796 error = ip_mrouter_set ? ip_mrouter_set(so, sopt) :
797 EOPNOTSUPP;
798 break;
799
800 default:
801 error = ip_ctloutput(so, sopt);
802 break;
803 }
804 break;
805 }
806
807 return (error);
808 }
809
810 /*
811 * This function exists solely to receive the PRC_IFDOWN messages which are
812 * sent by if_down(). It looks for an ifaddr whose ifa_addr is sa, and calls
813 * in_ifadown() to remove all routes corresponding to that address. It also
814 * receives the PRC_IFUP messages from if_up() and reinstalls the interface
815 * routes.
816 */
817 void
rip_ctlinput(int cmd,struct sockaddr * sa,void * vip)818 rip_ctlinput(int cmd, struct sockaddr *sa, void *vip)
819 {
820 struct rm_priotracker in_ifa_tracker;
821 struct in_ifaddr *ia;
822 struct ifnet *ifp;
823 int err;
824 int flags;
825
826 switch (cmd) {
827 case PRC_IFDOWN:
828 IN_IFADDR_RLOCK(&in_ifa_tracker);
829 CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
830 if (ia->ia_ifa.ifa_addr == sa
831 && (ia->ia_flags & IFA_ROUTE)) {
832 ifa_ref(&ia->ia_ifa);
833 IN_IFADDR_RUNLOCK(&in_ifa_tracker);
834 /*
835 * in_scrubprefix() kills the interface route.
836 */
837 in_scrubprefix(ia, 0);
838 /*
839 * in_ifadown gets rid of all the rest of the
840 * routes. This is not quite the right thing
841 * to do, but at least if we are running a
842 * routing process they will come back.
843 */
844 in_ifadown(&ia->ia_ifa, 0);
845 ifa_free(&ia->ia_ifa);
846 break;
847 }
848 }
849 if (ia == NULL) /* If ia matched, already unlocked. */
850 IN_IFADDR_RUNLOCK(&in_ifa_tracker);
851 break;
852
853 case PRC_IFUP:
854 IN_IFADDR_RLOCK(&in_ifa_tracker);
855 CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
856 if (ia->ia_ifa.ifa_addr == sa)
857 break;
858 }
859 if (ia == NULL || (ia->ia_flags & IFA_ROUTE)) {
860 IN_IFADDR_RUNLOCK(&in_ifa_tracker);
861 return;
862 }
863 ifa_ref(&ia->ia_ifa);
864 IN_IFADDR_RUNLOCK(&in_ifa_tracker);
865 flags = RTF_UP;
866 ifp = ia->ia_ifa.ifa_ifp;
867
868 if ((ifp->if_flags & IFF_LOOPBACK)
869 || (ifp->if_flags & IFF_POINTOPOINT))
870 flags |= RTF_HOST;
871
872 err = ifa_del_loopback_route((struct ifaddr *)ia, sa);
873
874 rt_addrmsg(RTM_ADD, &ia->ia_ifa, ia->ia_ifp->if_fib);
875 err = in_handle_ifaddr_route(RTM_ADD, ia);
876 if (err == 0)
877 ia->ia_flags |= IFA_ROUTE;
878
879 err = ifa_add_loopback_route((struct ifaddr *)ia, sa);
880
881 ifa_free(&ia->ia_ifa);
882 break;
883 }
884 }
885
886 static int
rip_attach(struct socket * so,int proto,struct thread * td)887 rip_attach(struct socket *so, int proto, struct thread *td)
888 {
889 struct inpcb *inp;
890 int error;
891
892 inp = sotoinpcb(so);
893 KASSERT(inp == NULL, ("rip_attach: inp != NULL"));
894
895 error = priv_check(td, PRIV_NETINET_RAW);
896 if (error)
897 return (error);
898 if (proto >= IPPROTO_MAX || proto < 0)
899 return EPROTONOSUPPORT;
900 error = soreserve(so, rip_sendspace, rip_recvspace);
901 if (error)
902 return (error);
903 INP_INFO_WLOCK(&V_ripcbinfo);
904 error = in_pcballoc(so, &V_ripcbinfo);
905 if (error) {
906 INP_INFO_WUNLOCK(&V_ripcbinfo);
907 return (error);
908 }
909 inp = (struct inpcb *)so->so_pcb;
910 inp->inp_vflag |= INP_IPV4;
911 inp->inp_ip_p = proto;
912 inp->inp_ip_ttl = V_ip_defttl;
913 rip_inshash(inp);
914 INP_INFO_WUNLOCK(&V_ripcbinfo);
915 INP_WUNLOCK(inp);
916 return (0);
917 }
918
919 static void
rip_detach(struct socket * so)920 rip_detach(struct socket *so)
921 {
922 struct inpcb *inp;
923
924 inp = sotoinpcb(so);
925 KASSERT(inp != NULL, ("rip_detach: inp == NULL"));
926 KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
927 ("rip_detach: not closed"));
928
929 INP_INFO_WLOCK(&V_ripcbinfo);
930 INP_WLOCK(inp);
931 rip_delhash(inp);
932 if (so == V_ip_mrouter && ip_mrouter_done)
933 ip_mrouter_done();
934 if (ip_rsvp_force_done)
935 ip_rsvp_force_done(so);
936 if (so == V_ip_rsvpd)
937 ip_rsvp_done();
938 in_pcbdetach(inp);
939 in_pcbfree(inp);
940 INP_INFO_WUNLOCK(&V_ripcbinfo);
941 }
942
943 static void
rip_dodisconnect(struct socket * so,struct inpcb * inp)944 rip_dodisconnect(struct socket *so, struct inpcb *inp)
945 {
946 struct inpcbinfo *pcbinfo;
947
948 pcbinfo = inp->inp_pcbinfo;
949 INP_INFO_WLOCK(pcbinfo);
950 INP_WLOCK(inp);
951 rip_delhash(inp);
952 inp->inp_faddr.s_addr = INADDR_ANY;
953 rip_inshash(inp);
954 SOCK_LOCK(so);
955 so->so_state &= ~SS_ISCONNECTED;
956 SOCK_UNLOCK(so);
957 INP_WUNLOCK(inp);
958 INP_INFO_WUNLOCK(pcbinfo);
959 }
960
961 static void
rip_abort(struct socket * so)962 rip_abort(struct socket *so)
963 {
964 struct inpcb *inp;
965
966 inp = sotoinpcb(so);
967 KASSERT(inp != NULL, ("rip_abort: inp == NULL"));
968
969 rip_dodisconnect(so, inp);
970 }
971
972 static void
rip_close(struct socket * so)973 rip_close(struct socket *so)
974 {
975 struct inpcb *inp;
976
977 inp = sotoinpcb(so);
978 KASSERT(inp != NULL, ("rip_close: inp == NULL"));
979
980 rip_dodisconnect(so, inp);
981 }
982
983 static int
rip_disconnect(struct socket * so)984 rip_disconnect(struct socket *so)
985 {
986 struct inpcb *inp;
987
988 if ((so->so_state & SS_ISCONNECTED) == 0)
989 return (ENOTCONN);
990
991 inp = sotoinpcb(so);
992 KASSERT(inp != NULL, ("rip_disconnect: inp == NULL"));
993
994 rip_dodisconnect(so, inp);
995 return (0);
996 }
997
998 static int
rip_bind(struct socket * so,struct sockaddr * nam,struct thread * td)999 rip_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1000 {
1001 struct sockaddr_in *addr = (struct sockaddr_in *)nam;
1002 struct inpcb *inp;
1003 int error;
1004
1005 if (nam->sa_family != AF_INET)
1006 return (EAFNOSUPPORT);
1007 if (nam->sa_len != sizeof(*addr))
1008 return (EINVAL);
1009
1010 error = prison_check_ip4(td->td_ucred, &addr->sin_addr);
1011 if (error != 0)
1012 return (error);
1013
1014 inp = sotoinpcb(so);
1015 KASSERT(inp != NULL, ("rip_bind: inp == NULL"));
1016
1017 if (CK_STAILQ_EMPTY(&V_ifnet) ||
1018 (addr->sin_family != AF_INET && addr->sin_family != AF_IMPLINK) ||
1019 (addr->sin_addr.s_addr &&
1020 (inp->inp_flags & INP_BINDANY) == 0 &&
1021 ifa_ifwithaddr_check((struct sockaddr *)addr) == 0))
1022 return (EADDRNOTAVAIL);
1023
1024 INP_INFO_WLOCK(&V_ripcbinfo);
1025 INP_WLOCK(inp);
1026 rip_delhash(inp);
1027 inp->inp_laddr = addr->sin_addr;
1028 rip_inshash(inp);
1029 INP_WUNLOCK(inp);
1030 INP_INFO_WUNLOCK(&V_ripcbinfo);
1031 return (0);
1032 }
1033
1034 static int
rip_connect(struct socket * so,struct sockaddr * nam,struct thread * td)1035 rip_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1036 {
1037 struct sockaddr_in *addr = (struct sockaddr_in *)nam;
1038 struct inpcb *inp;
1039
1040 if (nam->sa_len != sizeof(*addr))
1041 return (EINVAL);
1042 if (CK_STAILQ_EMPTY(&V_ifnet))
1043 return (EADDRNOTAVAIL);
1044 if (addr->sin_family != AF_INET && addr->sin_family != AF_IMPLINK)
1045 return (EAFNOSUPPORT);
1046
1047 inp = sotoinpcb(so);
1048 KASSERT(inp != NULL, ("rip_connect: inp == NULL"));
1049
1050 INP_INFO_WLOCK(&V_ripcbinfo);
1051 INP_WLOCK(inp);
1052 rip_delhash(inp);
1053 inp->inp_faddr = addr->sin_addr;
1054 rip_inshash(inp);
1055 soisconnected(so);
1056 INP_WUNLOCK(inp);
1057 INP_INFO_WUNLOCK(&V_ripcbinfo);
1058 return (0);
1059 }
1060
1061 static int
rip_shutdown(struct socket * so)1062 rip_shutdown(struct socket *so)
1063 {
1064 struct inpcb *inp;
1065
1066 inp = sotoinpcb(so);
1067 KASSERT(inp != NULL, ("rip_shutdown: inp == NULL"));
1068
1069 INP_WLOCK(inp);
1070 socantsendmore(so);
1071 INP_WUNLOCK(inp);
1072 return (0);
1073 }
1074
1075 static int
rip_send(struct socket * so,int flags,struct mbuf * m,struct sockaddr * nam,struct mbuf * control,struct thread * td)1076 rip_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
1077 struct mbuf *control, struct thread *td)
1078 {
1079 struct inpcb *inp;
1080 u_long dst;
1081 int error;
1082
1083 inp = sotoinpcb(so);
1084 KASSERT(inp != NULL, ("rip_send: inp == NULL"));
1085
1086 if (control != NULL) {
1087 m_freem(control);
1088 control = NULL;
1089 }
1090
1091 /*
1092 * Note: 'dst' reads below are unlocked.
1093 */
1094 if (so->so_state & SS_ISCONNECTED) {
1095 if (nam) {
1096 error = EISCONN;
1097 goto release;
1098 }
1099 dst = inp->inp_faddr.s_addr; /* Unlocked read. */
1100 } else {
1101 error = 0;
1102 if (nam == NULL)
1103 error = ENOTCONN;
1104 else if (nam->sa_family != AF_INET)
1105 error = EAFNOSUPPORT;
1106 else if (nam->sa_len != sizeof(struct sockaddr_in))
1107 error = EINVAL;
1108 if (error != 0)
1109 goto release;
1110 dst = ((struct sockaddr_in *)nam)->sin_addr.s_addr;
1111 }
1112 return (rip_output(m, so, dst));
1113
1114 release:
1115 m_freem(m);
1116 return (error);
1117 }
1118 #endif /* INET */
1119
1120 static int
rip_pcblist(SYSCTL_HANDLER_ARGS)1121 rip_pcblist(SYSCTL_HANDLER_ARGS)
1122 {
1123 struct xinpgen xig;
1124 struct epoch_tracker et;
1125 struct inpcb *inp;
1126 int error;
1127
1128 if (req->newptr != 0)
1129 return (EPERM);
1130
1131 if (req->oldptr == 0) {
1132 int n;
1133
1134 n = V_ripcbinfo.ipi_count;
1135 n += imax(n / 8, 10);
1136 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
1137 return (0);
1138 }
1139
1140 if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
1141 return (error);
1142
1143 bzero(&xig, sizeof(xig));
1144 xig.xig_len = sizeof xig;
1145 xig.xig_count = V_ripcbinfo.ipi_count;
1146 xig.xig_gen = V_ripcbinfo.ipi_gencnt;
1147 xig.xig_sogen = so_gencnt;
1148 error = SYSCTL_OUT(req, &xig, sizeof xig);
1149 if (error)
1150 return (error);
1151
1152 NET_EPOCH_ENTER(et);
1153 for (inp = CK_LIST_FIRST(V_ripcbinfo.ipi_listhead);
1154 inp != NULL;
1155 inp = CK_LIST_NEXT(inp, inp_list)) {
1156 INP_RLOCK(inp);
1157 if (inp->inp_gencnt <= xig.xig_gen &&
1158 cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
1159 struct xinpcb xi;
1160
1161 in_pcbtoxinpcb(inp, &xi);
1162 INP_RUNLOCK(inp);
1163 error = SYSCTL_OUT(req, &xi, sizeof xi);
1164 if (error)
1165 break;
1166 } else
1167 INP_RUNLOCK(inp);
1168 }
1169 NET_EPOCH_EXIT(et);
1170
1171 if (!error) {
1172 /*
1173 * Give the user an updated idea of our state. If the
1174 * generation differs from what we told her before, she knows
1175 * that something happened while we were processing this
1176 * request, and it might be necessary to retry.
1177 */
1178 xig.xig_gen = V_ripcbinfo.ipi_gencnt;
1179 xig.xig_sogen = so_gencnt;
1180 xig.xig_count = V_ripcbinfo.ipi_count;
1181 error = SYSCTL_OUT(req, &xig, sizeof xig);
1182 }
1183
1184 return (error);
1185 }
1186
1187 SYSCTL_PROC(_net_inet_raw, OID_AUTO/*XXX*/, pcblist,
1188 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
1189 rip_pcblist, "S,xinpcb",
1190 "List of active raw IP sockets");
1191
1192 #ifdef INET
1193 struct pr_usrreqs rip_usrreqs = {
1194 .pru_abort = rip_abort,
1195 .pru_attach = rip_attach,
1196 .pru_bind = rip_bind,
1197 .pru_connect = rip_connect,
1198 .pru_control = in_control,
1199 .pru_detach = rip_detach,
1200 .pru_disconnect = rip_disconnect,
1201 .pru_peeraddr = in_getpeeraddr,
1202 .pru_send = rip_send,
1203 .pru_shutdown = rip_shutdown,
1204 .pru_sockaddr = in_getsockaddr,
1205 .pru_sosetlabel = in_pcbsosetlabel,
1206 .pru_close = rip_close,
1207 };
1208 #endif /* INET */
1209