xref: /freebsd/usr.sbin/rtsold/rtsock.c (revision cab6a39d7b343596a5823e65c0f7b426551ec22d)
1 /*	$KAME: rtsock.c,v 1.3 2000/10/10 08:46:45 itojun Exp $	*/
2 /*	$FreeBSD$	*/
3 
4 /*-
5  * SPDX-License-Identifier: BSD-3-Clause
6  *
7  * Copyright (C) 2000 WIDE Project.
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the project nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/capsicum.h>
37 #include <sys/queue.h>
38 #include <sys/socket.h>
39 #include <sys/time.h>
40 #include <sys/uio.h>
41 
42 #include <net/if.h>
43 #include <net/route.h>
44 #include <net/if_dl.h>
45 
46 #include <netinet/in.h>
47 #include <netinet/ip6.h>
48 #include <netinet/icmp6.h>
49 
50 #include <capsicum_helpers.h>
51 #include <time.h>
52 #include <unistd.h>
53 #include <stdio.h>
54 #include <stddef.h>
55 #include <err.h>
56 #include <errno.h>
57 #include <string.h>
58 #include <stdlib.h>
59 #include <syslog.h>
60 #include "rtsold.h"
61 
62 static int rtsock_input_ifannounce(int, struct rt_msghdr *, char *);
63 
64 static struct {
65 	u_char type;
66 	size_t minlen;
67 	int (*func)(int, struct rt_msghdr *, char *);
68 } rtsock_dispatch[] = {
69 	{ RTM_IFANNOUNCE, sizeof(struct if_announcemsghdr),
70 	  rtsock_input_ifannounce },
71 	{ 0, 0, NULL },
72 };
73 
74 int
75 rtsock_open(void)
76 {
77 	cap_rights_t rights;
78 	int error, s;
79 
80 	s = socket(PF_ROUTE, SOCK_RAW, 0);
81 	if (s < 0)
82 		return (s);
83 	cap_rights_init(&rights, CAP_EVENT, CAP_READ);
84 	if (caph_rights_limit(s, &rights) != 0) {
85 		error = errno;
86 		(void)close(s);
87 		errno = error;
88 		return (-1);
89 	}
90 	return (s);
91 }
92 
93 int
94 rtsock_input(int s)
95 {
96 	ssize_t n;
97 	char msg[2048];
98 	char *lim, *next;
99 	struct rt_msghdr *rtm;
100 	int idx;
101 	ssize_t len;
102 	int ret = 0;
103 	const ssize_t lenlim =
104 	    offsetof(struct rt_msghdr, rtm_msglen) + sizeof(rtm->rtm_msglen);
105 
106 	n = read(s, msg, sizeof(msg));
107 
108 	lim = msg + n;
109 	for (next = msg; next < lim; next += len) {
110 		rtm = (struct rt_msghdr *)(void *)next;
111 		if (lim - next < lenlim)
112 			break;
113 		len = rtm->rtm_msglen;
114 		if (len < lenlim)
115 			break;
116 
117 		if (dflag > 1) {
118 			warnmsg(LOG_INFO, __func__,
119 			    "rtmsg type %d, len=%lu", rtm->rtm_type,
120 			    (u_long)len);
121 		}
122 
123 		for (idx = 0; rtsock_dispatch[idx].func; idx++) {
124 			if (rtm->rtm_type != rtsock_dispatch[idx].type)
125 				continue;
126 			if (rtm->rtm_msglen < rtsock_dispatch[idx].minlen) {
127 				warnmsg(LOG_INFO, __func__,
128 				    "rtmsg type %d too short!", rtm->rtm_type);
129 				continue;
130 			}
131 
132 			ret = (*rtsock_dispatch[idx].func)(s, rtm, lim);
133 			break;
134 		}
135 	}
136 
137 	return (ret);
138 }
139 
140 static int
141 rtsock_input_ifannounce(int s __unused, struct rt_msghdr *rtm, char *lim)
142 {
143 	struct if_announcemsghdr *ifan;
144 	struct ifinfo *ifi;
145 
146 	ifan = (struct if_announcemsghdr *)rtm;
147 	if ((char *)(ifan + 1) > lim)
148 		return (-1);
149 
150 	switch (ifan->ifan_what) {
151 	case IFAN_ARRIVAL:
152 		/*
153 		 * XXX for NetBSD 1.5, interface index will monotonically be
154 		 * increased as new pcmcia card gets inserted.
155 		 * we may be able to do a name-based interface match,
156 		 * and call ifreconfig() to enable the interface again.
157 		 */
158 		warnmsg(LOG_INFO, __func__,
159 		    "interface %s inserted", ifan->ifan_name);
160 		break;
161 	case IFAN_DEPARTURE:
162 		warnmsg(LOG_WARNING, __func__,
163 		    "interface %s removed", ifan->ifan_name);
164 		ifi = find_ifinfo(ifan->ifan_index);
165 		if (ifi) {
166 			if (dflag > 1) {
167 				warnmsg(LOG_INFO, __func__,
168 				    "bring interface %s to DOWN state",
169 				    ifan->ifan_name);
170 			}
171 			ifi->state = IFS_DOWN;
172 		}
173 		break;
174 	}
175 
176 	return (0);
177 }
178