xref: /freebsd/sys/netinet/raw_ip.c (revision 681ce946f33e75c590e97c53076e86dff1fe8f4a)
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/rwlock.h>
54 #include <sys/signalvar.h>
55 #include <sys/socket.h>
56 #include <sys/socketvar.h>
57 #include <sys/sx.h>
58 #include <sys/sysctl.h>
59 #include <sys/systm.h>
60 
61 #include <vm/uma.h>
62 
63 #include <net/if.h>
64 #include <net/if_var.h>
65 #include <net/route.h>
66 #include <net/route/route_ctl.h>
67 #include <net/vnet.h>
68 
69 #include <netinet/in.h>
70 #include <netinet/in_systm.h>
71 #include <netinet/in_fib.h>
72 #include <netinet/in_pcb.h>
73 #include <netinet/in_var.h>
74 #include <netinet/if_ether.h>
75 #include <netinet/ip.h>
76 #include <netinet/ip_var.h>
77 #include <netinet/ip_mroute.h>
78 #include <netinet/ip_icmp.h>
79 
80 #include <netipsec/ipsec_support.h>
81 
82 #include <machine/stdarg.h>
83 #include <security/mac/mac_framework.h>
84 
85 VNET_DEFINE(int, ip_defttl) = IPDEFTTL;
86 SYSCTL_INT(_net_inet_ip, IPCTL_DEFTTL, ttl, CTLFLAG_VNET | CTLFLAG_RW,
87     &VNET_NAME(ip_defttl), 0,
88     "Maximum TTL on IP packets");
89 
90 VNET_DEFINE(struct inpcbinfo, ripcbinfo);
91 #define	V_ripcbinfo		VNET(ripcbinfo)
92 
93 /*
94  * Control and data hooks for ipfw, dummynet, divert and so on.
95  * The data hooks are not used here but it is convenient
96  * to keep them all in one place.
97  */
98 VNET_DEFINE(ip_fw_chk_ptr_t, ip_fw_chk_ptr) = NULL;
99 VNET_DEFINE(ip_fw_ctl_ptr_t, ip_fw_ctl_ptr) = NULL;
100 
101 int	(*ip_dn_ctl_ptr)(struct sockopt *);
102 int	(*ip_dn_io_ptr)(struct mbuf **, struct ip_fw_args *);
103 void	(*ip_divert_ptr)(struct mbuf *, bool);
104 int	(*ng_ipfw_input_p)(struct mbuf **, struct ip_fw_args *, bool);
105 
106 #ifdef INET
107 /*
108  * Hooks for multicast routing. They all default to NULL, so leave them not
109  * initialized and rely on BSS being set to 0.
110  */
111 
112 /*
113  * The socket used to communicate with the multicast routing daemon.
114  */
115 VNET_DEFINE(struct socket *, ip_mrouter);
116 
117 /*
118  * The various mrouter and rsvp functions.
119  */
120 int (*ip_mrouter_set)(struct socket *, struct sockopt *);
121 int (*ip_mrouter_get)(struct socket *, struct sockopt *);
122 int (*ip_mrouter_done)(void);
123 int (*ip_mforward)(struct ip *, struct ifnet *, struct mbuf *,
124 		   struct ip_moptions *);
125 int (*mrt_ioctl)(u_long, caddr_t, int);
126 int (*legal_vif_num)(int);
127 u_long (*ip_mcast_src)(int);
128 
129 int (*rsvp_input_p)(struct mbuf **, int *, int);
130 int (*ip_rsvp_vif)(struct socket *, struct sockopt *);
131 void (*ip_rsvp_force_done)(struct socket *);
132 #endif /* INET */
133 
134 extern	struct protosw inetsw[];
135 
136 u_long	rip_sendspace = 9216;
137 SYSCTL_ULONG(_net_inet_raw, OID_AUTO, maxdgram, CTLFLAG_RW,
138     &rip_sendspace, 0, "Maximum outgoing raw IP datagram size");
139 
140 u_long	rip_recvspace = 9216;
141 SYSCTL_ULONG(_net_inet_raw, OID_AUTO, recvspace, CTLFLAG_RW,
142     &rip_recvspace, 0, "Maximum space for incoming raw IP datagrams");
143 
144 /*
145  * Hash functions
146  */
147 
148 #define INP_PCBHASH_RAW_SIZE	256
149 #define INP_PCBHASH_RAW(proto, laddr, faddr, mask) \
150         (((proto) + (laddr) + (faddr)) % (mask) + 1)
151 
152 #ifdef INET
153 static void
154 rip_inshash(struct inpcb *inp)
155 {
156 	struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
157 	struct inpcbhead *pcbhash;
158 	int hash;
159 
160 	INP_HASH_WLOCK_ASSERT(pcbinfo);
161 	INP_WLOCK_ASSERT(inp);
162 
163 	if (inp->inp_ip_p != 0 &&
164 	    inp->inp_laddr.s_addr != INADDR_ANY &&
165 	    inp->inp_faddr.s_addr != INADDR_ANY) {
166 		hash = INP_PCBHASH_RAW(inp->inp_ip_p, inp->inp_laddr.s_addr,
167 		    inp->inp_faddr.s_addr, pcbinfo->ipi_hashmask);
168 	} else
169 		hash = 0;
170 	pcbhash = &pcbinfo->ipi_hashbase[hash];
171 	CK_LIST_INSERT_HEAD(pcbhash, inp, inp_hash);
172 }
173 
174 static void
175 rip_delhash(struct inpcb *inp)
176 {
177 
178 	INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);
179 	INP_WLOCK_ASSERT(inp);
180 
181 	CK_LIST_REMOVE(inp, inp_hash);
182 }
183 #endif /* INET */
184 
185 /*
186  * Raw interface to IP protocol.
187  */
188 
189 /*
190  * Initialize raw connection block q.
191  */
192 static void
193 rip_zone_change(void *tag)
194 {
195 
196 	uma_zone_set_max(V_ripcbinfo.ipi_zone, maxsockets);
197 }
198 
199 static int
200 rip_inpcb_init(void *mem, int size, int flags)
201 {
202 	struct inpcb *inp = mem;
203 
204 	INP_LOCK_INIT(inp, "inp", "rawinp");
205 	return (0);
206 }
207 
208 void
209 rip_init(void)
210 {
211 
212 	in_pcbinfo_init(&V_ripcbinfo, "rip", INP_PCBHASH_RAW_SIZE, 1, "ripcb",
213 	    rip_inpcb_init);
214 	EVENTHANDLER_REGISTER(maxsockets_change, rip_zone_change, NULL,
215 	    EVENTHANDLER_PRI_ANY);
216 }
217 
218 #ifdef VIMAGE
219 static void
220 rip_destroy(void *unused __unused)
221 {
222 
223 	in_pcbinfo_destroy(&V_ripcbinfo);
224 }
225 VNET_SYSUNINIT(raw_ip, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, rip_destroy, NULL);
226 #endif
227 
228 #ifdef INET
229 static int
230 rip_append(struct inpcb *inp, struct ip *ip, struct mbuf *m,
231     struct sockaddr_in *ripsrc)
232 {
233 	struct socket *so = inp->inp_socket;
234 	struct mbuf *n, *opts = NULL;
235 
236 	INP_LOCK_ASSERT(inp);
237 
238 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
239 	/* check AH/ESP integrity. */
240 	if (IPSEC_ENABLED(ipv4) && IPSEC_CHECK_POLICY(ipv4, m, inp) != 0)
241 		return (0);
242 #endif /* IPSEC */
243 #ifdef MAC
244 	if (mac_inpcb_check_deliver(inp, m) != 0)
245 		return (0);
246 #endif
247 	/* Check the minimum TTL for socket. */
248 	if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl)
249 		return (0);
250 
251 	if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL)
252 		return (0);
253 
254 	if ((inp->inp_flags & INP_CONTROLOPTS) ||
255 	    (so->so_options & (SO_TIMESTAMP | SO_BINTIME)))
256 		ip_savecontrol(inp, &opts, ip, n);
257 	SOCKBUF_LOCK(&so->so_rcv);
258 	if (sbappendaddr_locked(&so->so_rcv,
259 	    (struct sockaddr *)ripsrc, n, opts) == 0) {
260 		soroverflow_locked(so);
261 		m_freem(n);
262 		if (opts)
263 			m_freem(opts);
264 		return (0);
265 	}
266 	sorwakeup_locked(so);
267 
268 	return (1);
269 }
270 
271 struct rip_inp_match_ctx {
272 	struct ip *ip;
273 	int proto;
274 };
275 
276 static bool
277 rip_inp_match1(const struct inpcb *inp, void *v)
278 {
279 	struct rip_inp_match_ctx *ctx = v;
280 
281 	if (inp->inp_ip_p != ctx->proto)
282 		return (false);
283 #ifdef INET6
284 	/* XXX inp locking */
285 	if ((inp->inp_vflag & INP_IPV4) == 0)
286 		return (false);
287 #endif
288 	if (inp->inp_laddr.s_addr != ctx->ip->ip_dst.s_addr)
289 		return (false);
290 	if (inp->inp_faddr.s_addr != ctx->ip->ip_src.s_addr)
291 		return (false);
292 	return (true);
293 }
294 
295 static bool
296 rip_inp_match2(const struct inpcb *inp, void *v)
297 {
298 	struct rip_inp_match_ctx *ctx = v;
299 
300 	if (inp->inp_ip_p && inp->inp_ip_p != ctx->proto)
301 		return (false);
302 #ifdef INET6
303 	/* XXX inp locking */
304 	if ((inp->inp_vflag & INP_IPV4) == 0)
305 		return (false);
306 #endif
307 	if (!in_nullhost(inp->inp_laddr) &&
308 	    !in_hosteq(inp->inp_laddr, ctx->ip->ip_dst))
309 		return (false);
310 	if (!in_nullhost(inp->inp_faddr) &&
311 	    !in_hosteq(inp->inp_faddr, ctx->ip->ip_src))
312 		return (false);
313 	return (true);
314 }
315 
316 /*
317  * Setup generic address and protocol structures for raw_input routine, then
318  * pass them along with mbuf chain.
319  */
320 int
321 rip_input(struct mbuf **mp, int *offp, int proto)
322 {
323 	struct rip_inp_match_ctx ctx = {
324 		.ip = mtod(*mp, struct ip *),
325 		.proto = proto,
326 	};
327 	struct inpcb_iterator inpi = INP_ITERATOR(&V_ripcbinfo,
328 	    INPLOOKUP_RLOCKPCB, rip_inp_match1, &ctx);
329 	struct ifnet *ifp;
330 	struct mbuf *m = *mp;
331 	struct inpcb *inp;
332 	struct sockaddr_in ripsrc;
333 	int appended;
334 
335 	*mp = NULL;
336 	appended = 0;
337 
338 	bzero(&ripsrc, sizeof(ripsrc));
339 	ripsrc.sin_len = sizeof(ripsrc);
340 	ripsrc.sin_family = AF_INET;
341 	ripsrc.sin_addr = ctx.ip->ip_src;
342 
343 	ifp = m->m_pkthdr.rcvif;
344 
345 	inpi.hash = INP_PCBHASH_RAW(proto, ctx.ip->ip_src.s_addr,
346 	    ctx.ip->ip_dst.s_addr, V_ripcbinfo.ipi_hashmask);
347 	while ((inp = inp_next(&inpi)) != NULL) {
348 		INP_RLOCK_ASSERT(inp);
349 		if (jailed_without_vnet(inp->inp_cred) &&
350 		    prison_check_ip4(inp->inp_cred, &ctx.ip->ip_dst) != 0) {
351 			/*
352 			 * XXX: If faddr was bound to multicast group,
353 			 * jailed raw socket will drop datagram.
354 			 */
355 			continue;
356 		}
357 		appended += rip_append(inp, ctx.ip, m, &ripsrc);
358 	}
359 
360 	inpi.hash = 0;
361 	inpi.match = rip_inp_match2;
362 	MPASS(inpi.inp == NULL);
363 	while ((inp = inp_next(&inpi)) != NULL) {
364 		INP_RLOCK_ASSERT(inp);
365 		if (jailed_without_vnet(inp->inp_cred) &&
366 		    !IN_MULTICAST(ntohl(ctx.ip->ip_dst.s_addr)) &&
367 		    prison_check_ip4(inp->inp_cred, &ctx.ip->ip_dst) != 0)
368 			/*
369 			 * Allow raw socket in jail to receive multicast;
370 			 * assume process had PRIV_NETINET_RAW at attach,
371 			 * and fall through into normal filter path if so.
372 			 */
373 			continue;
374 		/*
375 		 * If this raw socket has multicast state, and we
376 		 * have received a multicast, check if this socket
377 		 * should receive it, as multicast filtering is now
378 		 * the responsibility of the transport layer.
379 		 */
380 		if (inp->inp_moptions != NULL &&
381 		    IN_MULTICAST(ntohl(ctx.ip->ip_dst.s_addr))) {
382 			/*
383 			 * If the incoming datagram is for IGMP, allow it
384 			 * through unconditionally to the raw socket.
385 			 *
386 			 * In the case of IGMPv2, we may not have explicitly
387 			 * joined the group, and may have set IFF_ALLMULTI
388 			 * on the interface. imo_multi_filter() may discard
389 			 * control traffic we actually need to see.
390 			 *
391 			 * Userland multicast routing daemons should continue
392 			 * filter the control traffic appropriately.
393 			 */
394 			int blocked;
395 
396 			blocked = MCAST_PASS;
397 			if (proto != IPPROTO_IGMP) {
398 				struct sockaddr_in group;
399 
400 				bzero(&group, sizeof(struct sockaddr_in));
401 				group.sin_len = sizeof(struct sockaddr_in);
402 				group.sin_family = AF_INET;
403 				group.sin_addr = ctx.ip->ip_dst;
404 
405 				blocked = imo_multi_filter(inp->inp_moptions,
406 				    ifp,
407 				    (struct sockaddr *)&group,
408 				    (struct sockaddr *)&ripsrc);
409 			}
410 
411 			if (blocked != MCAST_PASS) {
412 				IPSTAT_INC(ips_notmember);
413 				continue;
414 			}
415 		}
416 		appended += rip_append(inp, ctx.ip, m, &ripsrc);
417 	}
418 	if (appended == 0 &&
419 	    inetsw[ip_protox[ctx.ip->ip_p]].pr_input == rip_input) {
420 		IPSTAT_INC(ips_noproto);
421 		IPSTAT_DEC(ips_delivered);
422 		icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PROTOCOL, 0, 0);
423 	} else
424 		m_freem(m);
425 	return (IPPROTO_DONE);
426 }
427 
428 /*
429  * Generate IP header and pass packet to ip_output.  Tack on options user may
430  * have setup with control call.
431  */
432 int
433 rip_output(struct mbuf *m, struct socket *so, ...)
434 {
435 	struct epoch_tracker et;
436 	struct ip *ip;
437 	int error;
438 	struct inpcb *inp = sotoinpcb(so);
439 	va_list ap;
440 	u_long dst;
441 	int flags = ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0) |
442 	    IP_ALLOWBROADCAST;
443 	int cnt, hlen;
444 	u_char opttype, optlen, *cp;
445 
446 	va_start(ap, so);
447 	dst = va_arg(ap, u_long);
448 	va_end(ap);
449 
450 	/*
451 	 * If the user handed us a complete IP packet, use it.  Otherwise,
452 	 * allocate an mbuf for a header and fill it in.
453 	 */
454 	if ((inp->inp_flags & INP_HDRINCL) == 0) {
455 		if (m->m_pkthdr.len + sizeof(struct ip) > IP_MAXPACKET) {
456 			m_freem(m);
457 			return(EMSGSIZE);
458 		}
459 		M_PREPEND(m, sizeof(struct ip), M_NOWAIT);
460 		if (m == NULL)
461 			return(ENOBUFS);
462 
463 		INP_RLOCK(inp);
464 		ip = mtod(m, struct ip *);
465 		ip->ip_tos = inp->inp_ip_tos;
466 		if (inp->inp_flags & INP_DONTFRAG)
467 			ip->ip_off = htons(IP_DF);
468 		else
469 			ip->ip_off = htons(0);
470 		ip->ip_p = inp->inp_ip_p;
471 		ip->ip_len = htons(m->m_pkthdr.len);
472 		ip->ip_src = inp->inp_laddr;
473 		ip->ip_dst.s_addr = dst;
474 #ifdef ROUTE_MPATH
475 		if (CALC_FLOWID_OUTBOUND) {
476 			uint32_t hash_type, hash_val;
477 
478 			hash_val = fib4_calc_software_hash(ip->ip_src,
479 			    ip->ip_dst, 0, 0, ip->ip_p, &hash_type);
480 			m->m_pkthdr.flowid = hash_val;
481 			M_HASHTYPE_SET(m, hash_type);
482 			flags |= IP_NODEFAULTFLOWID;
483 		}
484 #endif
485 		if (jailed(inp->inp_cred)) {
486 			/*
487 			 * prison_local_ip4() would be good enough but would
488 			 * let a source of INADDR_ANY pass, which we do not
489 			 * want to see from jails.
490 			 */
491 			if (ip->ip_src.s_addr == INADDR_ANY) {
492 				NET_EPOCH_ENTER(et);
493 				error = in_pcbladdr(inp, &ip->ip_dst,
494 				    &ip->ip_src, inp->inp_cred);
495 				NET_EPOCH_EXIT(et);
496 			} else {
497 				error = prison_local_ip4(inp->inp_cred,
498 				    &ip->ip_src);
499 			}
500 			if (error != 0) {
501 				INP_RUNLOCK(inp);
502 				m_freem(m);
503 				return (error);
504 			}
505 		}
506 		ip->ip_ttl = inp->inp_ip_ttl;
507 	} else {
508 		if (m->m_pkthdr.len > IP_MAXPACKET) {
509 			m_freem(m);
510 			return (EMSGSIZE);
511 		}
512 		if (m->m_pkthdr.len < sizeof(*ip)) {
513 			m_freem(m);
514 			return (EINVAL);
515 		}
516 		m = m_pullup(m, sizeof(*ip));
517 		if (m == NULL)
518 			return (ENOMEM);
519 		ip = mtod(m, struct ip *);
520 		hlen = ip->ip_hl << 2;
521 		if (m->m_len < hlen) {
522 			m = m_pullup(m, hlen);
523 			if (m == NULL)
524 				return (EINVAL);
525 			ip = mtod(m, struct ip *);
526 		}
527 #ifdef ROUTE_MPATH
528 		if (CALC_FLOWID_OUTBOUND) {
529 			uint32_t hash_type, hash_val;
530 
531 			hash_val = fib4_calc_software_hash(ip->ip_dst,
532 			    ip->ip_src, 0, 0, ip->ip_p, &hash_type);
533 			m->m_pkthdr.flowid = hash_val;
534 			M_HASHTYPE_SET(m, hash_type);
535 			flags |= IP_NODEFAULTFLOWID;
536 		}
537 #endif
538 		INP_RLOCK(inp);
539 		/*
540 		 * Don't allow both user specified and setsockopt options,
541 		 * and don't allow packet length sizes that will crash.
542 		 */
543 		if ((hlen < sizeof (*ip))
544 		    || ((hlen > sizeof (*ip)) && inp->inp_options)
545 		    || (ntohs(ip->ip_len) != m->m_pkthdr.len)) {
546 			INP_RUNLOCK(inp);
547 			m_freem(m);
548 			return (EINVAL);
549 		}
550 		error = prison_check_ip4(inp->inp_cred, &ip->ip_src);
551 		if (error != 0) {
552 			INP_RUNLOCK(inp);
553 			m_freem(m);
554 			return (error);
555 		}
556 		/*
557 		 * Don't allow IP options which do not have the required
558 		 * structure as specified in section 3.1 of RFC 791 on
559 		 * pages 15-23.
560 		 */
561 		cp = (u_char *)(ip + 1);
562 		cnt = hlen - sizeof (struct ip);
563 		for (; cnt > 0; cnt -= optlen, cp += optlen) {
564 			opttype = cp[IPOPT_OPTVAL];
565 			if (opttype == IPOPT_EOL)
566 				break;
567 			if (opttype == IPOPT_NOP) {
568 				optlen = 1;
569 				continue;
570 			}
571 			if (cnt < IPOPT_OLEN + sizeof(u_char)) {
572 				INP_RUNLOCK(inp);
573 				m_freem(m);
574 				return (EINVAL);
575 			}
576 			optlen = cp[IPOPT_OLEN];
577 			if (optlen < IPOPT_OLEN + sizeof(u_char) ||
578 			    optlen > cnt) {
579 				INP_RUNLOCK(inp);
580 				m_freem(m);
581 				return (EINVAL);
582 			}
583 		}
584 		/*
585 		 * This doesn't allow application to specify ID of zero,
586 		 * but we got this limitation from the beginning of history.
587 		 */
588 		if (ip->ip_id == 0)
589 			ip_fillid(ip);
590 
591 		/*
592 		 * XXX prevent ip_output from overwriting header fields.
593 		 */
594 		flags |= IP_RAWOUTPUT;
595 		IPSTAT_INC(ips_rawout);
596 	}
597 
598 	if (inp->inp_flags & INP_ONESBCAST)
599 		flags |= IP_SENDONES;
600 
601 #ifdef MAC
602 	mac_inpcb_create_mbuf(inp, m);
603 #endif
604 
605 	NET_EPOCH_ENTER(et);
606 	error = ip_output(m, inp->inp_options, NULL, flags,
607 	    inp->inp_moptions, inp);
608 	NET_EPOCH_EXIT(et);
609 	INP_RUNLOCK(inp);
610 	return (error);
611 }
612 
613 /*
614  * Raw IP socket option processing.
615  *
616  * IMPORTANT NOTE regarding access control: Traditionally, raw sockets could
617  * only be created by a privileged process, and as such, socket option
618  * operations to manage system properties on any raw socket were allowed to
619  * take place without explicit additional access control checks.  However,
620  * raw sockets can now also be created in jail(), and therefore explicit
621  * checks are now required.  Likewise, raw sockets can be used by a process
622  * after it gives up privilege, so some caution is required.  For options
623  * passed down to the IP layer via ip_ctloutput(), checks are assumed to be
624  * performed in ip_ctloutput() and therefore no check occurs here.
625  * Unilaterally checking priv_check() here breaks normal IP socket option
626  * operations on raw sockets.
627  *
628  * When adding new socket options here, make sure to add access control
629  * checks here as necessary.
630  *
631  * XXX-BZ inp locking?
632  */
633 int
634 rip_ctloutput(struct socket *so, struct sockopt *sopt)
635 {
636 	struct	inpcb *inp = sotoinpcb(so);
637 	int	error, optval;
638 
639 	if (sopt->sopt_level != IPPROTO_IP) {
640 		if ((sopt->sopt_level == SOL_SOCKET) &&
641 		    (sopt->sopt_name == SO_SETFIB)) {
642 			inp->inp_inc.inc_fibnum = so->so_fibnum;
643 			return (0);
644 		}
645 		return (EINVAL);
646 	}
647 
648 	error = 0;
649 	switch (sopt->sopt_dir) {
650 	case SOPT_GET:
651 		switch (sopt->sopt_name) {
652 		case IP_HDRINCL:
653 			optval = inp->inp_flags & INP_HDRINCL;
654 			error = sooptcopyout(sopt, &optval, sizeof optval);
655 			break;
656 
657 		case IP_FW3:	/* generic ipfw v.3 functions */
658 		case IP_FW_ADD:	/* ADD actually returns the body... */
659 		case IP_FW_GET:
660 		case IP_FW_TABLE_GETSIZE:
661 		case IP_FW_TABLE_LIST:
662 		case IP_FW_NAT_GET_CONFIG:
663 		case IP_FW_NAT_GET_LOG:
664 			if (V_ip_fw_ctl_ptr != NULL)
665 				error = V_ip_fw_ctl_ptr(sopt);
666 			else
667 				error = ENOPROTOOPT;
668 			break;
669 
670 		case IP_DUMMYNET3:	/* generic dummynet v.3 functions */
671 		case IP_DUMMYNET_GET:
672 			if (ip_dn_ctl_ptr != NULL)
673 				error = ip_dn_ctl_ptr(sopt);
674 			else
675 				error = ENOPROTOOPT;
676 			break ;
677 
678 		case MRT_INIT:
679 		case MRT_DONE:
680 		case MRT_ADD_VIF:
681 		case MRT_DEL_VIF:
682 		case MRT_ADD_MFC:
683 		case MRT_DEL_MFC:
684 		case MRT_VERSION:
685 		case MRT_ASSERT:
686 		case MRT_API_SUPPORT:
687 		case MRT_API_CONFIG:
688 		case MRT_ADD_BW_UPCALL:
689 		case MRT_DEL_BW_UPCALL:
690 			error = priv_check(curthread, PRIV_NETINET_MROUTE);
691 			if (error != 0)
692 				return (error);
693 			error = ip_mrouter_get ? ip_mrouter_get(so, sopt) :
694 				EOPNOTSUPP;
695 			break;
696 
697 		default:
698 			error = ip_ctloutput(so, sopt);
699 			break;
700 		}
701 		break;
702 
703 	case SOPT_SET:
704 		switch (sopt->sopt_name) {
705 		case IP_HDRINCL:
706 			error = sooptcopyin(sopt, &optval, sizeof optval,
707 					    sizeof optval);
708 			if (error)
709 				break;
710 			if (optval)
711 				inp->inp_flags |= INP_HDRINCL;
712 			else
713 				inp->inp_flags &= ~INP_HDRINCL;
714 			break;
715 
716 		case IP_FW3:	/* generic ipfw v.3 functions */
717 		case IP_FW_ADD:
718 		case IP_FW_DEL:
719 		case IP_FW_FLUSH:
720 		case IP_FW_ZERO:
721 		case IP_FW_RESETLOG:
722 		case IP_FW_TABLE_ADD:
723 		case IP_FW_TABLE_DEL:
724 		case IP_FW_TABLE_FLUSH:
725 		case IP_FW_NAT_CFG:
726 		case IP_FW_NAT_DEL:
727 			if (V_ip_fw_ctl_ptr != NULL)
728 				error = V_ip_fw_ctl_ptr(sopt);
729 			else
730 				error = ENOPROTOOPT;
731 			break;
732 
733 		case IP_DUMMYNET3:	/* generic dummynet v.3 functions */
734 		case IP_DUMMYNET_CONFIGURE:
735 		case IP_DUMMYNET_DEL:
736 		case IP_DUMMYNET_FLUSH:
737 			if (ip_dn_ctl_ptr != NULL)
738 				error = ip_dn_ctl_ptr(sopt);
739 			else
740 				error = ENOPROTOOPT ;
741 			break ;
742 
743 		case IP_RSVP_ON:
744 			error = priv_check(curthread, PRIV_NETINET_MROUTE);
745 			if (error != 0)
746 				return (error);
747 			error = ip_rsvp_init(so);
748 			break;
749 
750 		case IP_RSVP_OFF:
751 			error = priv_check(curthread, PRIV_NETINET_MROUTE);
752 			if (error != 0)
753 				return (error);
754 			error = ip_rsvp_done();
755 			break;
756 
757 		case IP_RSVP_VIF_ON:
758 		case IP_RSVP_VIF_OFF:
759 			error = priv_check(curthread, PRIV_NETINET_MROUTE);
760 			if (error != 0)
761 				return (error);
762 			error = ip_rsvp_vif ?
763 				ip_rsvp_vif(so, sopt) : EINVAL;
764 			break;
765 
766 		case MRT_INIT:
767 		case MRT_DONE:
768 		case MRT_ADD_VIF:
769 		case MRT_DEL_VIF:
770 		case MRT_ADD_MFC:
771 		case MRT_DEL_MFC:
772 		case MRT_VERSION:
773 		case MRT_ASSERT:
774 		case MRT_API_SUPPORT:
775 		case MRT_API_CONFIG:
776 		case MRT_ADD_BW_UPCALL:
777 		case MRT_DEL_BW_UPCALL:
778 			error = priv_check(curthread, PRIV_NETINET_MROUTE);
779 			if (error != 0)
780 				return (error);
781 			error = ip_mrouter_set ? ip_mrouter_set(so, sopt) :
782 					EOPNOTSUPP;
783 			break;
784 
785 		default:
786 			error = ip_ctloutput(so, sopt);
787 			break;
788 		}
789 		break;
790 	}
791 
792 	return (error);
793 }
794 
795 /*
796  * This function exists solely to receive the PRC_IFDOWN messages which are
797  * sent by if_down().  It looks for an ifaddr whose ifa_addr is sa, and calls
798  * in_ifadown() to remove all routes corresponding to that address.  It also
799  * receives the PRC_IFUP messages from if_up() and reinstalls the interface
800  * routes.
801  */
802 void
803 rip_ctlinput(int cmd, struct sockaddr *sa, void *vip)
804 {
805 	struct in_ifaddr *ia;
806 	struct ifnet *ifp;
807 	int err;
808 	int flags;
809 
810 	NET_EPOCH_ASSERT();
811 
812 	switch (cmd) {
813 	case PRC_IFDOWN:
814 		CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
815 			if (ia->ia_ifa.ifa_addr == sa
816 			    && (ia->ia_flags & IFA_ROUTE)) {
817 				ifa_ref(&ia->ia_ifa);
818 				/*
819 				 * in_scrubprefix() kills the interface route.
820 				 */
821 				in_scrubprefix(ia, 0);
822 				/*
823 				 * in_ifadown gets rid of all the rest of the
824 				 * routes.  This is not quite the right thing
825 				 * to do, but at least if we are running a
826 				 * routing process they will come back.
827 				 */
828 				in_ifadown(&ia->ia_ifa, 0);
829 				ifa_free(&ia->ia_ifa);
830 				break;
831 			}
832 		}
833 		break;
834 
835 	case PRC_IFUP:
836 		CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
837 			if (ia->ia_ifa.ifa_addr == sa)
838 				break;
839 		}
840 		if (ia == NULL || (ia->ia_flags & IFA_ROUTE))
841 			return;
842 		ifa_ref(&ia->ia_ifa);
843 		flags = RTF_UP;
844 		ifp = ia->ia_ifa.ifa_ifp;
845 
846 		if ((ifp->if_flags & IFF_LOOPBACK)
847 		    || (ifp->if_flags & IFF_POINTOPOINT))
848 			flags |= RTF_HOST;
849 
850 		err = ifa_del_loopback_route((struct ifaddr *)ia, sa);
851 
852 		rt_addrmsg(RTM_ADD, &ia->ia_ifa, ia->ia_ifp->if_fib);
853 		err = in_handle_ifaddr_route(RTM_ADD, ia);
854 		if (err == 0)
855 			ia->ia_flags |= IFA_ROUTE;
856 
857 		err = ifa_add_loopback_route((struct ifaddr *)ia, sa);
858 
859 		ifa_free(&ia->ia_ifa);
860 		break;
861 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
862 	case PRC_MSGSIZE:
863 		if (IPSEC_ENABLED(ipv4))
864 			IPSEC_CTLINPUT(ipv4, cmd, sa, vip);
865 		break;
866 #endif
867 	}
868 }
869 
870 static int
871 rip_attach(struct socket *so, int proto, struct thread *td)
872 {
873 	struct inpcb *inp;
874 	int error;
875 
876 	inp = sotoinpcb(so);
877 	KASSERT(inp == NULL, ("rip_attach: inp != NULL"));
878 
879 	error = priv_check(td, PRIV_NETINET_RAW);
880 	if (error)
881 		return (error);
882 	if (proto >= IPPROTO_MAX || proto < 0)
883 		return EPROTONOSUPPORT;
884 	error = soreserve(so, rip_sendspace, rip_recvspace);
885 	if (error)
886 		return (error);
887 	error = in_pcballoc(so, &V_ripcbinfo);
888 	if (error)
889 		return (error);
890 	inp = (struct inpcb *)so->so_pcb;
891 	inp->inp_vflag |= INP_IPV4;
892 	inp->inp_ip_p = proto;
893 	inp->inp_ip_ttl = V_ip_defttl;
894 	INP_HASH_WLOCK(&V_ripcbinfo);
895 	rip_inshash(inp);
896 	INP_HASH_WUNLOCK(&V_ripcbinfo);
897 	INP_WUNLOCK(inp);
898 	return (0);
899 }
900 
901 static void
902 rip_detach(struct socket *so)
903 {
904 	struct inpcb *inp;
905 
906 	inp = sotoinpcb(so);
907 	KASSERT(inp != NULL, ("rip_detach: inp == NULL"));
908 	KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
909 	    ("rip_detach: not closed"));
910 
911 	INP_WLOCK(inp);
912 	INP_HASH_WLOCK(&V_ripcbinfo);
913 	rip_delhash(inp);
914 	INP_HASH_WUNLOCK(&V_ripcbinfo);
915 	if (so == V_ip_mrouter && ip_mrouter_done)
916 		ip_mrouter_done();
917 	if (ip_rsvp_force_done)
918 		ip_rsvp_force_done(so);
919 	if (so == V_ip_rsvpd)
920 		ip_rsvp_done();
921 	in_pcbdetach(inp);
922 	in_pcbfree(inp);
923 }
924 
925 static void
926 rip_dodisconnect(struct socket *so, struct inpcb *inp)
927 {
928 	struct inpcbinfo *pcbinfo;
929 
930 	pcbinfo = inp->inp_pcbinfo;
931 	INP_WLOCK(inp);
932 	INP_HASH_WLOCK(pcbinfo);
933 	rip_delhash(inp);
934 	inp->inp_faddr.s_addr = INADDR_ANY;
935 	rip_inshash(inp);
936 	INP_HASH_WUNLOCK(pcbinfo);
937 	SOCK_LOCK(so);
938 	so->so_state &= ~SS_ISCONNECTED;
939 	SOCK_UNLOCK(so);
940 	INP_WUNLOCK(inp);
941 }
942 
943 static void
944 rip_abort(struct socket *so)
945 {
946 	struct inpcb *inp;
947 
948 	inp = sotoinpcb(so);
949 	KASSERT(inp != NULL, ("rip_abort: inp == NULL"));
950 
951 	rip_dodisconnect(so, inp);
952 }
953 
954 static void
955 rip_close(struct socket *so)
956 {
957 	struct inpcb *inp;
958 
959 	inp = sotoinpcb(so);
960 	KASSERT(inp != NULL, ("rip_close: inp == NULL"));
961 
962 	rip_dodisconnect(so, inp);
963 }
964 
965 static int
966 rip_disconnect(struct socket *so)
967 {
968 	struct inpcb *inp;
969 
970 	if ((so->so_state & SS_ISCONNECTED) == 0)
971 		return (ENOTCONN);
972 
973 	inp = sotoinpcb(so);
974 	KASSERT(inp != NULL, ("rip_disconnect: inp == NULL"));
975 
976 	rip_dodisconnect(so, inp);
977 	return (0);
978 }
979 
980 static int
981 rip_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
982 {
983 	struct sockaddr_in *addr = (struct sockaddr_in *)nam;
984 	struct inpcb *inp;
985 	int error;
986 
987 	if (nam->sa_family != AF_INET)
988 		return (EAFNOSUPPORT);
989 	if (nam->sa_len != sizeof(*addr))
990 		return (EINVAL);
991 
992 	error = prison_check_ip4(td->td_ucred, &addr->sin_addr);
993 	if (error != 0)
994 		return (error);
995 
996 	inp = sotoinpcb(so);
997 	KASSERT(inp != NULL, ("rip_bind: inp == NULL"));
998 
999 	if (CK_STAILQ_EMPTY(&V_ifnet) ||
1000 	    (addr->sin_family != AF_INET && addr->sin_family != AF_IMPLINK) ||
1001 	    (addr->sin_addr.s_addr &&
1002 	     (inp->inp_flags & INP_BINDANY) == 0 &&
1003 	     ifa_ifwithaddr_check((struct sockaddr *)addr) == 0))
1004 		return (EADDRNOTAVAIL);
1005 
1006 	INP_WLOCK(inp);
1007 	INP_HASH_WLOCK(&V_ripcbinfo);
1008 	rip_delhash(inp);
1009 	inp->inp_laddr = addr->sin_addr;
1010 	rip_inshash(inp);
1011 	INP_HASH_WUNLOCK(&V_ripcbinfo);
1012 	INP_WUNLOCK(inp);
1013 	return (0);
1014 }
1015 
1016 static int
1017 rip_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1018 {
1019 	struct sockaddr_in *addr = (struct sockaddr_in *)nam;
1020 	struct inpcb *inp;
1021 
1022 	if (nam->sa_len != sizeof(*addr))
1023 		return (EINVAL);
1024 	if (CK_STAILQ_EMPTY(&V_ifnet))
1025 		return (EADDRNOTAVAIL);
1026 	if (addr->sin_family != AF_INET && addr->sin_family != AF_IMPLINK)
1027 		return (EAFNOSUPPORT);
1028 
1029 	inp = sotoinpcb(so);
1030 	KASSERT(inp != NULL, ("rip_connect: inp == NULL"));
1031 
1032 	INP_WLOCK(inp);
1033 	INP_HASH_WLOCK(&V_ripcbinfo);
1034 	rip_delhash(inp);
1035 	inp->inp_faddr = addr->sin_addr;
1036 	rip_inshash(inp);
1037 	INP_HASH_WUNLOCK(&V_ripcbinfo);
1038 	soisconnected(so);
1039 	INP_WUNLOCK(inp);
1040 	return (0);
1041 }
1042 
1043 static int
1044 rip_shutdown(struct socket *so)
1045 {
1046 	struct inpcb *inp;
1047 
1048 	inp = sotoinpcb(so);
1049 	KASSERT(inp != NULL, ("rip_shutdown: inp == NULL"));
1050 
1051 	INP_WLOCK(inp);
1052 	socantsendmore(so);
1053 	INP_WUNLOCK(inp);
1054 	return (0);
1055 }
1056 
1057 static int
1058 rip_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
1059     struct mbuf *control, struct thread *td)
1060 {
1061 	struct inpcb *inp;
1062 	u_long dst;
1063 	int error;
1064 
1065 	inp = sotoinpcb(so);
1066 	KASSERT(inp != NULL, ("rip_send: inp == NULL"));
1067 
1068 	if (control != NULL) {
1069 		m_freem(control);
1070 		control = NULL;
1071 	}
1072 
1073 	/*
1074 	 * Note: 'dst' reads below are unlocked.
1075 	 */
1076 	if (so->so_state & SS_ISCONNECTED) {
1077 		if (nam) {
1078 			error = EISCONN;
1079 			goto release;
1080 		}
1081 		dst = inp->inp_faddr.s_addr;	/* Unlocked read. */
1082 	} else {
1083 		error = 0;
1084 		if (nam == NULL)
1085 			error = ENOTCONN;
1086 		else if (nam->sa_family != AF_INET)
1087 			error = EAFNOSUPPORT;
1088 		else if (nam->sa_len != sizeof(struct sockaddr_in))
1089 			error = EINVAL;
1090 		if (error != 0)
1091 			goto release;
1092 		dst = ((struct sockaddr_in *)nam)->sin_addr.s_addr;
1093 	}
1094 	return (rip_output(m, so, dst));
1095 
1096 release:
1097 	m_freem(m);
1098 	return (error);
1099 }
1100 #endif /* INET */
1101 
1102 static int
1103 rip_pcblist(SYSCTL_HANDLER_ARGS)
1104 {
1105 	struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_ripcbinfo,
1106 	    INPLOOKUP_RLOCKPCB);
1107 	struct xinpgen xig;
1108 	struct inpcb *inp;
1109 	int error;
1110 
1111 	if (req->newptr != 0)
1112 		return (EPERM);
1113 
1114 	if (req->oldptr == 0) {
1115 		int n;
1116 
1117 		n = V_ripcbinfo.ipi_count;
1118 		n += imax(n / 8, 10);
1119 		req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xinpcb);
1120 		return (0);
1121 	}
1122 
1123 	if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
1124 		return (error);
1125 
1126 	bzero(&xig, sizeof(xig));
1127 	xig.xig_len = sizeof xig;
1128 	xig.xig_count = V_ripcbinfo.ipi_count;
1129 	xig.xig_gen = V_ripcbinfo.ipi_gencnt;
1130 	xig.xig_sogen = so_gencnt;
1131 	error = SYSCTL_OUT(req, &xig, sizeof xig);
1132 	if (error)
1133 		return (error);
1134 
1135 	while ((inp = inp_next(&inpi)) != NULL) {
1136 		if (inp->inp_gencnt <= xig.xig_gen &&
1137 		    cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
1138 			struct xinpcb xi;
1139 
1140 			in_pcbtoxinpcb(inp, &xi);
1141 			error = SYSCTL_OUT(req, &xi, sizeof xi);
1142 			if (error) {
1143 				INP_RUNLOCK(inp);
1144 				break;
1145 			}
1146 		}
1147 	}
1148 
1149 	if (!error) {
1150 		/*
1151 		 * Give the user an updated idea of our state.  If the
1152 		 * generation differs from what we told her before, she knows
1153 		 * that something happened while we were processing this
1154 		 * request, and it might be necessary to retry.
1155 		 */
1156 		xig.xig_gen = V_ripcbinfo.ipi_gencnt;
1157 		xig.xig_sogen = so_gencnt;
1158 		xig.xig_count = V_ripcbinfo.ipi_count;
1159 		error = SYSCTL_OUT(req, &xig, sizeof xig);
1160 	}
1161 
1162 	return (error);
1163 }
1164 
1165 SYSCTL_PROC(_net_inet_raw, OID_AUTO/*XXX*/, pcblist,
1166     CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0,
1167     rip_pcblist, "S,xinpcb",
1168     "List of active raw IP sockets");
1169 
1170 #ifdef INET
1171 struct pr_usrreqs rip_usrreqs = {
1172 	.pru_abort =		rip_abort,
1173 	.pru_attach =		rip_attach,
1174 	.pru_bind =		rip_bind,
1175 	.pru_connect =		rip_connect,
1176 	.pru_control =		in_control,
1177 	.pru_detach =		rip_detach,
1178 	.pru_disconnect =	rip_disconnect,
1179 	.pru_peeraddr =		in_getpeeraddr,
1180 	.pru_send =		rip_send,
1181 	.pru_shutdown =		rip_shutdown,
1182 	.pru_sockaddr =		in_getsockaddr,
1183 	.pru_sosetlabel =	in_pcbsosetlabel,
1184 	.pru_close =		rip_close,
1185 };
1186 #endif /* INET */
1187