raw_ip.c revision 205251
1/*-
2 * Copyright (c) 1982, 1986, 1988, 1993
3 *	The Regents of the University of California.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 4. Neither the name of the University nor the names of its contributors
15 *    may be used to endorse or promote products derived from this software
16 *    without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 *	@(#)raw_ip.c	8.7 (Berkeley) 5/15/95
31 */
32
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: head/sys/netinet/raw_ip.c 205251 2010-03-17 18:28:27Z bz $");
35
36#include "opt_inet6.h"
37#include "opt_ipsec.h"
38
39#include <sys/param.h>
40#include <sys/jail.h>
41#include <sys/kernel.h>
42#include <sys/lock.h>
43#include <sys/malloc.h>
44#include <sys/mbuf.h>
45#include <sys/priv.h>
46#include <sys/proc.h>
47#include <sys/protosw.h>
48#include <sys/rwlock.h>
49#include <sys/signalvar.h>
50#include <sys/socket.h>
51#include <sys/socketvar.h>
52#include <sys/sx.h>
53#include <sys/sysctl.h>
54#include <sys/systm.h>
55
56#include <vm/uma.h>
57
58#include <net/if.h>
59#include <net/route.h>
60#include <net/vnet.h>
61
62#include <netinet/in.h>
63#include <netinet/in_systm.h>
64#include <netinet/in_pcb.h>
65#include <netinet/in_var.h>
66#include <netinet/ip.h>
67#include <netinet/ip_var.h>
68#include <netinet/ip_mroute.h>
69
70#ifdef IPSEC
71#include <netipsec/ipsec.h>
72#endif /*IPSEC*/
73
74#include <security/mac/mac_framework.h>
75
76VNET_DEFINE(struct inpcbhead, ripcb);
77VNET_DEFINE(struct inpcbinfo, ripcbinfo);
78
79#define	V_ripcb			VNET(ripcb)
80#define	V_ripcbinfo		VNET(ripcbinfo)
81
82/*
83 * Control and data hooks for ipfw, dummynet, divert and so on.
84 * The data hooks are not used here but it is convenient
85 * to keep them all in one place.
86 */
87VNET_DEFINE(ip_fw_chk_ptr_t, ip_fw_chk_ptr) = NULL;
88VNET_DEFINE(ip_fw_ctl_ptr_t, ip_fw_ctl_ptr) = NULL;
89
90int	(*ip_dn_ctl_ptr)(struct sockopt *);
91int	(*ip_dn_io_ptr)(struct mbuf **, int, struct ip_fw_args *);
92void	(*ip_divert_ptr)(struct mbuf *, int);
93int	(*ng_ipfw_input_p)(struct mbuf **, int,
94			struct ip_fw_args *, int);
95
96/*
97 * Hooks for multicast routing. They all default to NULL, so leave them not
98 * initialized and rely on BSS being set to 0.
99 */
100
101/*
102 * The socket used to communicate with the multicast routing daemon.
103 */
104VNET_DEFINE(struct socket *, ip_mrouter);
105
106/*
107 * The various mrouter and rsvp functions.
108 */
109int (*ip_mrouter_set)(struct socket *, struct sockopt *);
110int (*ip_mrouter_get)(struct socket *, struct sockopt *);
111int (*ip_mrouter_done)(void);
112int (*ip_mforward)(struct ip *, struct ifnet *, struct mbuf *,
113		   struct ip_moptions *);
114int (*mrt_ioctl)(u_long, caddr_t, int);
115int (*legal_vif_num)(int);
116u_long (*ip_mcast_src)(int);
117
118void (*rsvp_input_p)(struct mbuf *m, int off);
119int (*ip_rsvp_vif)(struct socket *, struct sockopt *);
120void (*ip_rsvp_force_done)(struct socket *);
121
122/*
123 * Hash functions
124 */
125
126#define INP_PCBHASH_RAW_SIZE	256
127#define INP_PCBHASH_RAW(proto, laddr, faddr, mask) \
128        (((proto) + (laddr) + (faddr)) % (mask) + 1)
129
130static void
131rip_inshash(struct inpcb *inp)
132{
133	struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
134	struct inpcbhead *pcbhash;
135	int hash;
136
137	INP_INFO_WLOCK_ASSERT(pcbinfo);
138	INP_WLOCK_ASSERT(inp);
139
140	if (inp->inp_ip_p != 0 &&
141	    inp->inp_laddr.s_addr != INADDR_ANY &&
142	    inp->inp_faddr.s_addr != INADDR_ANY) {
143		hash = INP_PCBHASH_RAW(inp->inp_ip_p, inp->inp_laddr.s_addr,
144		    inp->inp_faddr.s_addr, pcbinfo->ipi_hashmask);
145	} else
146		hash = 0;
147	pcbhash = &pcbinfo->ipi_hashbase[hash];
148	LIST_INSERT_HEAD(pcbhash, inp, inp_hash);
149}
150
151static void
152rip_delhash(struct inpcb *inp)
153{
154
155	INP_INFO_WLOCK_ASSERT(inp->inp_pcbinfo);
156	INP_WLOCK_ASSERT(inp);
157
158	LIST_REMOVE(inp, inp_hash);
159}
160
161/*
162 * Raw interface to IP protocol.
163 */
164
165/*
166 * Initialize raw connection block q.
167 */
168static void
169rip_zone_change(void *tag)
170{
171
172	uma_zone_set_max(V_ripcbinfo.ipi_zone, maxsockets);
173}
174
175static int
176rip_inpcb_init(void *mem, int size, int flags)
177{
178	struct inpcb *inp = mem;
179
180	INP_LOCK_INIT(inp, "inp", "rawinp");
181	return (0);
182}
183
184void
185rip_init(void)
186{
187
188	in_pcbinfo_init(&V_ripcbinfo, "rip", &V_ripcb, INP_PCBHASH_RAW_SIZE,
189	    1, "ripcb", rip_inpcb_init, NULL, UMA_ZONE_NOFREE);
190	EVENTHANDLER_REGISTER(maxsockets_change, rip_zone_change, NULL,
191	    EVENTHANDLER_PRI_ANY);
192}
193
194#ifdef VIMAGE
195void
196rip_destroy(void)
197{
198
199	in_pcbinfo_destroy(&V_ripcbinfo);
200}
201#endif
202
203static int
204rip_append(struct inpcb *last, struct ip *ip, struct mbuf *n,
205    struct sockaddr_in *ripsrc)
206{
207	int policyfail = 0;
208
209	INP_RLOCK_ASSERT(last);
210
211#ifdef IPSEC
212	/* check AH/ESP integrity. */
213	if (ipsec4_in_reject(n, last)) {
214		policyfail = 1;
215	}
216#endif /* IPSEC */
217#ifdef MAC
218	if (!policyfail && mac_inpcb_check_deliver(last, n) != 0)
219		policyfail = 1;
220#endif
221	/* Check the minimum TTL for socket. */
222	if (last->inp_ip_minttl && last->inp_ip_minttl > ip->ip_ttl)
223		policyfail = 1;
224	if (!policyfail) {
225		struct mbuf *opts = NULL;
226		struct socket *so;
227
228		so = last->inp_socket;
229		if ((last->inp_flags & INP_CONTROLOPTS) ||
230		    (so->so_options & (SO_TIMESTAMP | SO_BINTIME)))
231			ip_savecontrol(last, &opts, ip, n);
232		SOCKBUF_LOCK(&so->so_rcv);
233		if (sbappendaddr_locked(&so->so_rcv,
234		    (struct sockaddr *)ripsrc, n, opts) == 0) {
235			/* should notify about lost packet */
236			m_freem(n);
237			if (opts)
238				m_freem(opts);
239			SOCKBUF_UNLOCK(&so->so_rcv);
240		} else
241			sorwakeup_locked(so);
242	} else
243		m_freem(n);
244	return (policyfail);
245}
246
247/*
248 * Setup generic address and protocol structures for raw_input routine, then
249 * pass them along with mbuf chain.
250 */
251void
252rip_input(struct mbuf *m, int off)
253{
254	struct ifnet *ifp;
255	struct ip *ip = mtod(m, struct ip *);
256	int proto = ip->ip_p;
257	struct inpcb *inp, *last;
258	struct sockaddr_in ripsrc;
259	int hash;
260
261	bzero(&ripsrc, sizeof(ripsrc));
262	ripsrc.sin_len = sizeof(ripsrc);
263	ripsrc.sin_family = AF_INET;
264	ripsrc.sin_addr = ip->ip_src;
265	last = NULL;
266
267	ifp = m->m_pkthdr.rcvif;
268
269	hash = INP_PCBHASH_RAW(proto, ip->ip_src.s_addr,
270	    ip->ip_dst.s_addr, V_ripcbinfo.ipi_hashmask);
271	INP_INFO_RLOCK(&V_ripcbinfo);
272	LIST_FOREACH(inp, &V_ripcbinfo.ipi_hashbase[hash], inp_hash) {
273		if (inp->inp_ip_p != proto)
274			continue;
275#ifdef INET6
276		/* XXX inp locking */
277		if ((inp->inp_vflag & INP_IPV4) == 0)
278			continue;
279#endif
280		if (inp->inp_laddr.s_addr != ip->ip_dst.s_addr)
281			continue;
282		if (inp->inp_faddr.s_addr != ip->ip_src.s_addr)
283			continue;
284		if (jailed_without_vnet(inp->inp_cred)) {
285			/*
286			 * XXX: If faddr was bound to multicast group,
287			 * jailed raw socket will drop datagram.
288			 */
289			if (prison_check_ip4(inp->inp_cred, &ip->ip_dst) != 0)
290				continue;
291		}
292		if (last != NULL) {
293			struct mbuf *n;
294
295			n = m_copy(m, 0, (int)M_COPYALL);
296			if (n != NULL)
297		    	    (void) rip_append(last, ip, n, &ripsrc);
298			/* XXX count dropped packet */
299			INP_RUNLOCK(last);
300		}
301		INP_RLOCK(inp);
302		last = inp;
303	}
304	LIST_FOREACH(inp, &V_ripcbinfo.ipi_hashbase[0], inp_hash) {
305		if (inp->inp_ip_p && inp->inp_ip_p != proto)
306			continue;
307#ifdef INET6
308		/* XXX inp locking */
309		if ((inp->inp_vflag & INP_IPV4) == 0)
310			continue;
311#endif
312		if (!in_nullhost(inp->inp_laddr) &&
313		    !in_hosteq(inp->inp_laddr, ip->ip_dst))
314			continue;
315		if (!in_nullhost(inp->inp_faddr) &&
316		    !in_hosteq(inp->inp_faddr, ip->ip_src))
317			continue;
318		if (jailed_without_vnet(inp->inp_cred)) {
319			/*
320			 * Allow raw socket in jail to receive multicast;
321			 * assume process had PRIV_NETINET_RAW at attach,
322			 * and fall through into normal filter path if so.
323			 */
324			if (!IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) &&
325			    prison_check_ip4(inp->inp_cred, &ip->ip_dst) != 0)
326				continue;
327		}
328		/*
329		 * If this raw socket has multicast state, and we
330		 * have received a multicast, check if this socket
331		 * should receive it, as multicast filtering is now
332		 * the responsibility of the transport layer.
333		 */
334		if (inp->inp_moptions != NULL &&
335		    IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) {
336			/*
337			 * If the incoming datagram is for IGMP, allow it
338			 * through unconditionally to the raw socket.
339			 *
340			 * In the case of IGMPv2, we may not have explicitly
341			 * joined the group, and may have set IFF_ALLMULTI
342			 * on the interface. imo_multi_filter() may discard
343			 * control traffic we actually need to see.
344			 *
345			 * Userland multicast routing daemons should continue
346			 * filter the control traffic appropriately.
347			 */
348			int blocked;
349
350			blocked = MCAST_PASS;
351			if (proto != IPPROTO_IGMP) {
352				struct sockaddr_in group;
353
354				bzero(&group, sizeof(struct sockaddr_in));
355				group.sin_len = sizeof(struct sockaddr_in);
356				group.sin_family = AF_INET;
357				group.sin_addr = ip->ip_dst;
358
359				blocked = imo_multi_filter(inp->inp_moptions,
360				    ifp,
361				    (struct sockaddr *)&group,
362				    (struct sockaddr *)&ripsrc);
363			}
364
365			if (blocked != MCAST_PASS) {
366				IPSTAT_INC(ips_notmember);
367				continue;
368			}
369		}
370		if (last != NULL) {
371			struct mbuf *n;
372
373			n = m_copy(m, 0, (int)M_COPYALL);
374			if (n != NULL)
375				(void) rip_append(last, ip, n, &ripsrc);
376			/* XXX count dropped packet */
377			INP_RUNLOCK(last);
378		}
379		INP_RLOCK(inp);
380		last = inp;
381	}
382	INP_INFO_RUNLOCK(&V_ripcbinfo);
383	if (last != NULL) {
384		if (rip_append(last, ip, m, &ripsrc) != 0)
385			IPSTAT_INC(ips_delivered);
386		INP_RUNLOCK(last);
387	} else {
388		m_freem(m);
389		IPSTAT_INC(ips_noproto);
390		IPSTAT_DEC(ips_delivered);
391	}
392}
393
394/*
395 * Generate IP header and pass packet to ip_output.  Tack on options user may
396 * have setup with control call.
397 */
398int
399rip_output(struct mbuf *m, struct socket *so, u_long dst)
400{
401	struct ip *ip;
402	int error;
403	struct inpcb *inp = sotoinpcb(so);
404	int flags = ((so->so_options & SO_DONTROUTE) ? IP_ROUTETOIF : 0) |
405	    IP_ALLOWBROADCAST;
406
407	/*
408	 * If the user handed us a complete IP packet, use it.  Otherwise,
409	 * allocate an mbuf for a header and fill it in.
410	 */
411	if ((inp->inp_flags & INP_HDRINCL) == 0) {
412		if (m->m_pkthdr.len + sizeof(struct ip) > IP_MAXPACKET) {
413			m_freem(m);
414			return(EMSGSIZE);
415		}
416		M_PREPEND(m, sizeof(struct ip), M_DONTWAIT);
417		if (m == NULL)
418			return(ENOBUFS);
419
420		INP_RLOCK(inp);
421		ip = mtod(m, struct ip *);
422		ip->ip_tos = inp->inp_ip_tos;
423		if (inp->inp_flags & INP_DONTFRAG)
424			ip->ip_off = IP_DF;
425		else
426			ip->ip_off = 0;
427		ip->ip_p = inp->inp_ip_p;
428		ip->ip_len = m->m_pkthdr.len;
429		ip->ip_src = inp->inp_laddr;
430		error = prison_get_ip4(inp->inp_cred, &ip->ip_src);
431		if (error != 0) {
432			INP_RUNLOCK(inp);
433			m_freem(m);
434			return (error);
435		}
436		ip->ip_dst.s_addr = dst;
437		ip->ip_ttl = inp->inp_ip_ttl;
438	} else {
439		if (m->m_pkthdr.len > IP_MAXPACKET) {
440			m_freem(m);
441			return(EMSGSIZE);
442		}
443		INP_RLOCK(inp);
444		ip = mtod(m, struct ip *);
445		error = prison_check_ip4(inp->inp_cred, &ip->ip_src);
446		if (error != 0) {
447			INP_RUNLOCK(inp);
448			m_freem(m);
449			return (error);
450		}
451
452		/*
453		 * Don't allow both user specified and setsockopt options,
454		 * and don't allow packet length sizes that will crash.
455		 */
456		if (((ip->ip_hl != (sizeof (*ip) >> 2)) && inp->inp_options)
457		    || (ip->ip_len > m->m_pkthdr.len)
458		    || (ip->ip_len < (ip->ip_hl << 2))) {
459			INP_RUNLOCK(inp);
460			m_freem(m);
461			return (EINVAL);
462		}
463		if (ip->ip_id == 0)
464			ip->ip_id = ip_newid();
465
466		/*
467		 * XXX prevent ip_output from overwriting header fields.
468		 */
469		flags |= IP_RAWOUTPUT;
470		IPSTAT_INC(ips_rawout);
471	}
472
473	if (inp->inp_flags & INP_ONESBCAST)
474		flags |= IP_SENDONES;
475
476#ifdef MAC
477	mac_inpcb_create_mbuf(inp, m);
478#endif
479
480	error = ip_output(m, inp->inp_options, NULL, flags,
481	    inp->inp_moptions, inp);
482	INP_RUNLOCK(inp);
483	return (error);
484}
485
486/*
487 * Raw IP socket option processing.
488 *
489 * IMPORTANT NOTE regarding access control: Traditionally, raw sockets could
490 * only be created by a privileged process, and as such, socket option
491 * operations to manage system properties on any raw socket were allowed to
492 * take place without explicit additional access control checks.  However,
493 * raw sockets can now also be created in jail(), and therefore explicit
494 * checks are now required.  Likewise, raw sockets can be used by a process
495 * after it gives up privilege, so some caution is required.  For options
496 * passed down to the IP layer via ip_ctloutput(), checks are assumed to be
497 * performed in ip_ctloutput() and therefore no check occurs here.
498 * Unilaterally checking priv_check() here breaks normal IP socket option
499 * operations on raw sockets.
500 *
501 * When adding new socket options here, make sure to add access control
502 * checks here as necessary.
503 */
504int
505rip_ctloutput(struct socket *so, struct sockopt *sopt)
506{
507	struct	inpcb *inp = sotoinpcb(so);
508	int	error, optval;
509
510	if (sopt->sopt_level != IPPROTO_IP) {
511		if ((sopt->sopt_level == SOL_SOCKET) &&
512		    (sopt->sopt_name == SO_SETFIB)) {
513			inp->inp_inc.inc_fibnum = so->so_fibnum;
514			return (0);
515		}
516		return (EINVAL);
517	}
518
519	error = 0;
520	switch (sopt->sopt_dir) {
521	case SOPT_GET:
522		switch (sopt->sopt_name) {
523		case IP_HDRINCL:
524			optval = inp->inp_flags & INP_HDRINCL;
525			error = sooptcopyout(sopt, &optval, sizeof optval);
526			break;
527
528		case IP_FW3:	/* generic ipfw v.3 functions */
529		case IP_FW_ADD:	/* ADD actually returns the body... */
530		case IP_FW_GET:
531		case IP_FW_TABLE_GETSIZE:
532		case IP_FW_TABLE_LIST:
533		case IP_FW_NAT_GET_CONFIG:
534		case IP_FW_NAT_GET_LOG:
535			if (V_ip_fw_ctl_ptr != NULL)
536				error = V_ip_fw_ctl_ptr(sopt);
537			else
538				error = ENOPROTOOPT;
539			break;
540
541		case IP_DUMMYNET3:	/* generic dummynet v.3 functions */
542		case IP_DUMMYNET_GET:
543			if (ip_dn_ctl_ptr != NULL)
544				error = ip_dn_ctl_ptr(sopt);
545			else
546				error = ENOPROTOOPT;
547			break ;
548
549		case MRT_INIT:
550		case MRT_DONE:
551		case MRT_ADD_VIF:
552		case MRT_DEL_VIF:
553		case MRT_ADD_MFC:
554		case MRT_DEL_MFC:
555		case MRT_VERSION:
556		case MRT_ASSERT:
557		case MRT_API_SUPPORT:
558		case MRT_API_CONFIG:
559		case MRT_ADD_BW_UPCALL:
560		case MRT_DEL_BW_UPCALL:
561			error = priv_check(curthread, PRIV_NETINET_MROUTE);
562			if (error != 0)
563				return (error);
564			error = ip_mrouter_get ? ip_mrouter_get(so, sopt) :
565				EOPNOTSUPP;
566			break;
567
568		default:
569			error = ip_ctloutput(so, sopt);
570			break;
571		}
572		break;
573
574	case SOPT_SET:
575		switch (sopt->sopt_name) {
576		case IP_HDRINCL:
577			error = sooptcopyin(sopt, &optval, sizeof optval,
578					    sizeof optval);
579			if (error)
580				break;
581			if (optval)
582				inp->inp_flags |= INP_HDRINCL;
583			else
584				inp->inp_flags &= ~INP_HDRINCL;
585			break;
586
587		case IP_FW3:	/* generic ipfw v.3 functions */
588		case IP_FW_ADD:
589		case IP_FW_DEL:
590		case IP_FW_FLUSH:
591		case IP_FW_ZERO:
592		case IP_FW_RESETLOG:
593		case IP_FW_TABLE_ADD:
594		case IP_FW_TABLE_DEL:
595		case IP_FW_TABLE_FLUSH:
596		case IP_FW_NAT_CFG:
597		case IP_FW_NAT_DEL:
598			if (V_ip_fw_ctl_ptr != NULL)
599				error = V_ip_fw_ctl_ptr(sopt);
600			else
601				error = ENOPROTOOPT;
602			break;
603
604		case IP_DUMMYNET3:	/* generic dummynet v.3 functions */
605		case IP_DUMMYNET_CONFIGURE:
606		case IP_DUMMYNET_DEL:
607		case IP_DUMMYNET_FLUSH:
608			if (ip_dn_ctl_ptr != NULL)
609				error = ip_dn_ctl_ptr(sopt);
610			else
611				error = ENOPROTOOPT ;
612			break ;
613
614		case IP_RSVP_ON:
615			error = priv_check(curthread, PRIV_NETINET_MROUTE);
616			if (error != 0)
617				return (error);
618			error = ip_rsvp_init(so);
619			break;
620
621		case IP_RSVP_OFF:
622			error = priv_check(curthread, PRIV_NETINET_MROUTE);
623			if (error != 0)
624				return (error);
625			error = ip_rsvp_done();
626			break;
627
628		case IP_RSVP_VIF_ON:
629		case IP_RSVP_VIF_OFF:
630			error = priv_check(curthread, PRIV_NETINET_MROUTE);
631			if (error != 0)
632				return (error);
633			error = ip_rsvp_vif ?
634				ip_rsvp_vif(so, sopt) : EINVAL;
635			break;
636
637		case MRT_INIT:
638		case MRT_DONE:
639		case MRT_ADD_VIF:
640		case MRT_DEL_VIF:
641		case MRT_ADD_MFC:
642		case MRT_DEL_MFC:
643		case MRT_VERSION:
644		case MRT_ASSERT:
645		case MRT_API_SUPPORT:
646		case MRT_API_CONFIG:
647		case MRT_ADD_BW_UPCALL:
648		case MRT_DEL_BW_UPCALL:
649			error = priv_check(curthread, PRIV_NETINET_MROUTE);
650			if (error != 0)
651				return (error);
652			error = ip_mrouter_set ? ip_mrouter_set(so, sopt) :
653					EOPNOTSUPP;
654			break;
655
656		default:
657			error = ip_ctloutput(so, sopt);
658			break;
659		}
660		break;
661	}
662
663	return (error);
664}
665
666/*
667 * This function exists solely to receive the PRC_IFDOWN messages which are
668 * sent by if_down().  It looks for an ifaddr whose ifa_addr is sa, and calls
669 * in_ifadown() to remove all routes corresponding to that address.  It also
670 * receives the PRC_IFUP messages from if_up() and reinstalls the interface
671 * routes.
672 */
673void
674rip_ctlinput(int cmd, struct sockaddr *sa, void *vip)
675{
676	struct in_ifaddr *ia;
677	struct ifnet *ifp;
678	int err;
679	int flags;
680
681	switch (cmd) {
682	case PRC_IFDOWN:
683		IN_IFADDR_RLOCK();
684		TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
685			if (ia->ia_ifa.ifa_addr == sa
686			    && (ia->ia_flags & IFA_ROUTE)) {
687				ifa_ref(&ia->ia_ifa);
688				IN_IFADDR_RUNLOCK();
689				/*
690				 * in_ifscrub kills the interface route.
691				 */
692				in_ifscrub(ia->ia_ifp, ia);
693				/*
694				 * in_ifadown gets rid of all the rest of the
695				 * routes.  This is not quite the right thing
696				 * to do, but at least if we are running a
697				 * routing process they will come back.
698				 */
699				in_ifadown(&ia->ia_ifa, 0);
700				ifa_free(&ia->ia_ifa);
701				break;
702			}
703		}
704		if (ia == NULL)		/* If ia matched, already unlocked. */
705			IN_IFADDR_RUNLOCK();
706		break;
707
708	case PRC_IFUP:
709		IN_IFADDR_RLOCK();
710		TAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
711			if (ia->ia_ifa.ifa_addr == sa)
712				break;
713		}
714		if (ia == NULL || (ia->ia_flags & IFA_ROUTE)) {
715			IN_IFADDR_RUNLOCK();
716			return;
717		}
718		ifa_ref(&ia->ia_ifa);
719		IN_IFADDR_RUNLOCK();
720		flags = RTF_UP;
721		ifp = ia->ia_ifa.ifa_ifp;
722
723		if ((ifp->if_flags & IFF_LOOPBACK)
724		    || (ifp->if_flags & IFF_POINTOPOINT))
725			flags |= RTF_HOST;
726
727		err = rtinit(&ia->ia_ifa, RTM_ADD, flags);
728		if (err == 0)
729			ia->ia_flags |= IFA_ROUTE;
730		err = ifa_add_loopback_route((struct ifaddr *)ia, sa);
731		ifa_free(&ia->ia_ifa);
732		break;
733	}
734}
735
736u_long	rip_sendspace = 9216;
737u_long	rip_recvspace = 9216;
738
739SYSCTL_ULONG(_net_inet_raw, OID_AUTO, maxdgram, CTLFLAG_RW,
740    &rip_sendspace, 0, "Maximum outgoing raw IP datagram size");
741SYSCTL_ULONG(_net_inet_raw, OID_AUTO, recvspace, CTLFLAG_RW,
742    &rip_recvspace, 0, "Maximum space for incoming raw IP datagrams");
743
744static int
745rip_attach(struct socket *so, int proto, struct thread *td)
746{
747	struct inpcb *inp;
748	int error;
749
750	inp = sotoinpcb(so);
751	KASSERT(inp == NULL, ("rip_attach: inp != NULL"));
752
753	error = priv_check(td, PRIV_NETINET_RAW);
754	if (error)
755		return (error);
756	if (proto >= IPPROTO_MAX || proto < 0)
757		return EPROTONOSUPPORT;
758	error = soreserve(so, rip_sendspace, rip_recvspace);
759	if (error)
760		return (error);
761	INP_INFO_WLOCK(&V_ripcbinfo);
762	error = in_pcballoc(so, &V_ripcbinfo);
763	if (error) {
764		INP_INFO_WUNLOCK(&V_ripcbinfo);
765		return (error);
766	}
767	inp = (struct inpcb *)so->so_pcb;
768	inp->inp_vflag |= INP_IPV4;
769	inp->inp_ip_p = proto;
770	inp->inp_ip_ttl = V_ip_defttl;
771	rip_inshash(inp);
772	INP_INFO_WUNLOCK(&V_ripcbinfo);
773	INP_WUNLOCK(inp);
774	return (0);
775}
776
777static void
778rip_detach(struct socket *so)
779{
780	struct inpcb *inp;
781
782	inp = sotoinpcb(so);
783	KASSERT(inp != NULL, ("rip_detach: inp == NULL"));
784	KASSERT(inp->inp_faddr.s_addr == INADDR_ANY,
785	    ("rip_detach: not closed"));
786
787	INP_INFO_WLOCK(&V_ripcbinfo);
788	INP_WLOCK(inp);
789	rip_delhash(inp);
790	if (so == V_ip_mrouter && ip_mrouter_done)
791		ip_mrouter_done();
792	if (ip_rsvp_force_done)
793		ip_rsvp_force_done(so);
794	if (so == V_ip_rsvpd)
795		ip_rsvp_done();
796	in_pcbdetach(inp);
797	in_pcbfree(inp);
798	INP_INFO_WUNLOCK(&V_ripcbinfo);
799}
800
801static void
802rip_dodisconnect(struct socket *so, struct inpcb *inp)
803{
804
805	INP_INFO_WLOCK_ASSERT(inp->inp_pcbinfo);
806	INP_WLOCK_ASSERT(inp);
807
808	rip_delhash(inp);
809	inp->inp_faddr.s_addr = INADDR_ANY;
810	rip_inshash(inp);
811	SOCK_LOCK(so);
812	so->so_state &= ~SS_ISCONNECTED;
813	SOCK_UNLOCK(so);
814}
815
816static void
817rip_abort(struct socket *so)
818{
819	struct inpcb *inp;
820
821	inp = sotoinpcb(so);
822	KASSERT(inp != NULL, ("rip_abort: inp == NULL"));
823
824	INP_INFO_WLOCK(&V_ripcbinfo);
825	INP_WLOCK(inp);
826	rip_dodisconnect(so, inp);
827	INP_WUNLOCK(inp);
828	INP_INFO_WUNLOCK(&V_ripcbinfo);
829}
830
831static void
832rip_close(struct socket *so)
833{
834	struct inpcb *inp;
835
836	inp = sotoinpcb(so);
837	KASSERT(inp != NULL, ("rip_close: inp == NULL"));
838
839	INP_INFO_WLOCK(&V_ripcbinfo);
840	INP_WLOCK(inp);
841	rip_dodisconnect(so, inp);
842	INP_WUNLOCK(inp);
843	INP_INFO_WUNLOCK(&V_ripcbinfo);
844}
845
846static int
847rip_disconnect(struct socket *so)
848{
849	struct inpcb *inp;
850
851	if ((so->so_state & SS_ISCONNECTED) == 0)
852		return (ENOTCONN);
853
854	inp = sotoinpcb(so);
855	KASSERT(inp != NULL, ("rip_disconnect: inp == NULL"));
856
857	INP_INFO_WLOCK(&V_ripcbinfo);
858	INP_WLOCK(inp);
859	rip_dodisconnect(so, inp);
860	INP_WUNLOCK(inp);
861	INP_INFO_WUNLOCK(&V_ripcbinfo);
862	return (0);
863}
864
865static int
866rip_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
867{
868	struct sockaddr_in *addr = (struct sockaddr_in *)nam;
869	struct inpcb *inp;
870	int error;
871
872	if (nam->sa_len != sizeof(*addr))
873		return (EINVAL);
874
875	error = prison_check_ip4(td->td_ucred, &addr->sin_addr);
876	if (error != 0)
877		return (error);
878
879	inp = sotoinpcb(so);
880	KASSERT(inp != NULL, ("rip_bind: inp == NULL"));
881
882	if (TAILQ_EMPTY(&V_ifnet) ||
883	    (addr->sin_family != AF_INET && addr->sin_family != AF_IMPLINK) ||
884	    (addr->sin_addr.s_addr &&
885	     (inp->inp_flags & INP_BINDANY) == 0 &&
886	     ifa_ifwithaddr_check((struct sockaddr *)addr) == 0))
887		return (EADDRNOTAVAIL);
888
889	INP_INFO_WLOCK(&V_ripcbinfo);
890	INP_WLOCK(inp);
891	rip_delhash(inp);
892	inp->inp_laddr = addr->sin_addr;
893	rip_inshash(inp);
894	INP_WUNLOCK(inp);
895	INP_INFO_WUNLOCK(&V_ripcbinfo);
896	return (0);
897}
898
899static int
900rip_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
901{
902	struct sockaddr_in *addr = (struct sockaddr_in *)nam;
903	struct inpcb *inp;
904
905	if (nam->sa_len != sizeof(*addr))
906		return (EINVAL);
907	if (TAILQ_EMPTY(&V_ifnet))
908		return (EADDRNOTAVAIL);
909	if (addr->sin_family != AF_INET && addr->sin_family != AF_IMPLINK)
910		return (EAFNOSUPPORT);
911
912	inp = sotoinpcb(so);
913	KASSERT(inp != NULL, ("rip_connect: inp == NULL"));
914
915	INP_INFO_WLOCK(&V_ripcbinfo);
916	INP_WLOCK(inp);
917	rip_delhash(inp);
918	inp->inp_faddr = addr->sin_addr;
919	rip_inshash(inp);
920	soisconnected(so);
921	INP_WUNLOCK(inp);
922	INP_INFO_WUNLOCK(&V_ripcbinfo);
923	return (0);
924}
925
926static int
927rip_shutdown(struct socket *so)
928{
929	struct inpcb *inp;
930
931	inp = sotoinpcb(so);
932	KASSERT(inp != NULL, ("rip_shutdown: inp == NULL"));
933
934	INP_WLOCK(inp);
935	socantsendmore(so);
936	INP_WUNLOCK(inp);
937	return (0);
938}
939
940static int
941rip_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
942    struct mbuf *control, struct thread *td)
943{
944	struct inpcb *inp;
945	u_long dst;
946
947	inp = sotoinpcb(so);
948	KASSERT(inp != NULL, ("rip_send: inp == NULL"));
949
950	/*
951	 * Note: 'dst' reads below are unlocked.
952	 */
953	if (so->so_state & SS_ISCONNECTED) {
954		if (nam) {
955			m_freem(m);
956			return (EISCONN);
957		}
958		dst = inp->inp_faddr.s_addr;	/* Unlocked read. */
959	} else {
960		if (nam == NULL) {
961			m_freem(m);
962			return (ENOTCONN);
963		}
964		dst = ((struct sockaddr_in *)nam)->sin_addr.s_addr;
965	}
966	return (rip_output(m, so, dst));
967}
968
969static int
970rip_pcblist(SYSCTL_HANDLER_ARGS)
971{
972	int error, i, n;
973	struct inpcb *inp, **inp_list;
974	inp_gen_t gencnt;
975	struct xinpgen xig;
976
977	/*
978	 * The process of preparing the TCB list is too time-consuming and
979	 * resource-intensive to repeat twice on every request.
980	 */
981	if (req->oldptr == 0) {
982		n = V_ripcbinfo.ipi_count;
983		req->oldidx = 2 * (sizeof xig)
984		    + (n + n/8) * sizeof(struct xinpcb);
985		return (0);
986	}
987
988	if (req->newptr != 0)
989		return (EPERM);
990
991	/*
992	 * OK, now we're committed to doing something.
993	 */
994	INP_INFO_RLOCK(&V_ripcbinfo);
995	gencnt = V_ripcbinfo.ipi_gencnt;
996	n = V_ripcbinfo.ipi_count;
997	INP_INFO_RUNLOCK(&V_ripcbinfo);
998
999	xig.xig_len = sizeof xig;
1000	xig.xig_count = n;
1001	xig.xig_gen = gencnt;
1002	xig.xig_sogen = so_gencnt;
1003	error = SYSCTL_OUT(req, &xig, sizeof xig);
1004	if (error)
1005		return (error);
1006
1007	inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
1008	if (inp_list == 0)
1009		return (ENOMEM);
1010
1011	INP_INFO_RLOCK(&V_ripcbinfo);
1012	for (inp = LIST_FIRST(V_ripcbinfo.ipi_listhead), i = 0; inp && i < n;
1013	     inp = LIST_NEXT(inp, inp_list)) {
1014		INP_WLOCK(inp);
1015		if (inp->inp_gencnt <= gencnt &&
1016		    cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
1017			in_pcbref(inp);
1018			inp_list[i++] = inp;
1019		}
1020		INP_WUNLOCK(inp);
1021	}
1022	INP_INFO_RUNLOCK(&V_ripcbinfo);
1023	n = i;
1024
1025	error = 0;
1026	for (i = 0; i < n; i++) {
1027		inp = inp_list[i];
1028		INP_RLOCK(inp);
1029		if (inp->inp_gencnt <= gencnt) {
1030			struct xinpcb xi;
1031
1032			bzero(&xi, sizeof(xi));
1033			xi.xi_len = sizeof xi;
1034			/* XXX should avoid extra copy */
1035			bcopy(inp, &xi.xi_inp, sizeof *inp);
1036			if (inp->inp_socket)
1037				sotoxsocket(inp->inp_socket, &xi.xi_socket);
1038			INP_RUNLOCK(inp);
1039			error = SYSCTL_OUT(req, &xi, sizeof xi);
1040		} else
1041			INP_RUNLOCK(inp);
1042	}
1043	INP_INFO_WLOCK(&V_ripcbinfo);
1044	for (i = 0; i < n; i++) {
1045		inp = inp_list[i];
1046		INP_WLOCK(inp);
1047		if (!in_pcbrele(inp))
1048			INP_WUNLOCK(inp);
1049	}
1050	INP_INFO_WUNLOCK(&V_ripcbinfo);
1051
1052	if (!error) {
1053		/*
1054		 * Give the user an updated idea of our state.  If the
1055		 * generation differs from what we told her before, she knows
1056		 * that something happened while we were processing this
1057		 * request, and it might be necessary to retry.
1058		 */
1059		INP_INFO_RLOCK(&V_ripcbinfo);
1060		xig.xig_gen = V_ripcbinfo.ipi_gencnt;
1061		xig.xig_sogen = so_gencnt;
1062		xig.xig_count = V_ripcbinfo.ipi_count;
1063		INP_INFO_RUNLOCK(&V_ripcbinfo);
1064		error = SYSCTL_OUT(req, &xig, sizeof xig);
1065	}
1066	free(inp_list, M_TEMP);
1067	return (error);
1068}
1069
1070SYSCTL_PROC(_net_inet_raw, OID_AUTO/*XXX*/, pcblist, CTLFLAG_RD, 0, 0,
1071    rip_pcblist, "S,xinpcb", "List of active raw IP sockets");
1072
1073struct pr_usrreqs rip_usrreqs = {
1074	.pru_abort =		rip_abort,
1075	.pru_attach =		rip_attach,
1076	.pru_bind =		rip_bind,
1077	.pru_connect =		rip_connect,
1078	.pru_control =		in_control,
1079	.pru_detach =		rip_detach,
1080	.pru_disconnect =	rip_disconnect,
1081	.pru_peeraddr =		in_getpeeraddr,
1082	.pru_send =		rip_send,
1083	.pru_shutdown =		rip_shutdown,
1084	.pru_sockaddr =		in_getsockaddr,
1085	.pru_sosetlabel =	in_pcbsosetlabel,
1086	.pru_close =		rip_close,
1087};
1088