xref: /freebsd/usr.sbin/rtsold/rtsock.c (revision 61ba55bcf70f2340f9c943c9571113b3fd8eda69)
1 /*	$KAME: rtsock.c,v 1.3 2000/10/10 08:46:45 itojun Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  * Copyright (C) 2000 WIDE Project.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the project nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/param.h>
35 #include <sys/capsicum.h>
36 #include <sys/queue.h>
37 #include <sys/socket.h>
38 #include <sys/time.h>
39 #include <sys/uio.h>
40 
41 #include <net/if.h>
42 #include <net/route.h>
43 #include <net/if_dl.h>
44 
45 #include <netinet/in.h>
46 #include <netinet/ip6.h>
47 #include <netinet/icmp6.h>
48 
49 #include <capsicum_helpers.h>
50 #include <time.h>
51 #include <unistd.h>
52 #include <stdio.h>
53 #include <stddef.h>
54 #include <err.h>
55 #include <errno.h>
56 #include <string.h>
57 #include <stdlib.h>
58 #include <syslog.h>
59 #include "rtsold.h"
60 
61 static int rtsock_input_ifannounce(int, struct rt_msghdr *, char *);
62 
63 static struct {
64 	u_char type;
65 	size_t minlen;
66 	int (*func)(int, struct rt_msghdr *, char *);
67 } rtsock_dispatch[] = {
68 	{ RTM_IFANNOUNCE, sizeof(struct if_announcemsghdr),
69 	  rtsock_input_ifannounce },
70 	{ 0, 0, NULL },
71 };
72 
73 int
74 rtsock_open(void)
75 {
76 	cap_rights_t rights;
77 	int error, s;
78 
79 	s = socket(PF_ROUTE, SOCK_RAW, 0);
80 	if (s < 0)
81 		return (s);
82 	cap_rights_init(&rights, CAP_EVENT, CAP_READ);
83 	if (caph_rights_limit(s, &rights) != 0) {
84 		error = errno;
85 		(void)close(s);
86 		errno = error;
87 		return (-1);
88 	}
89 	return (s);
90 }
91 
92 int
93 rtsock_input(int s)
94 {
95 	ssize_t n;
96 	char msg[2048];
97 	char *lim, *next;
98 	struct rt_msghdr *rtm;
99 	int idx;
100 	ssize_t len;
101 	int ret = 0;
102 	const ssize_t lenlim =
103 	    offsetof(struct rt_msghdr, rtm_msglen) + sizeof(rtm->rtm_msglen);
104 
105 	n = read(s, msg, sizeof(msg));
106 
107 	lim = msg + n;
108 	for (next = msg; next < lim; next += len) {
109 		rtm = (struct rt_msghdr *)(void *)next;
110 		if (lim - next < lenlim)
111 			break;
112 		len = rtm->rtm_msglen;
113 		if (len < lenlim)
114 			break;
115 
116 		if (dflag > 1) {
117 			warnmsg(LOG_INFO, __func__,
118 			    "rtmsg type %d, len=%lu", rtm->rtm_type,
119 			    (u_long)len);
120 		}
121 
122 		for (idx = 0; rtsock_dispatch[idx].func; idx++) {
123 			if (rtm->rtm_type != rtsock_dispatch[idx].type)
124 				continue;
125 			if (rtm->rtm_msglen < rtsock_dispatch[idx].minlen) {
126 				warnmsg(LOG_INFO, __func__,
127 				    "rtmsg type %d too short!", rtm->rtm_type);
128 				continue;
129 			}
130 
131 			ret = (*rtsock_dispatch[idx].func)(s, rtm, lim);
132 			break;
133 		}
134 	}
135 
136 	return (ret);
137 }
138 
139 static int
140 rtsock_input_ifannounce(int s __unused, struct rt_msghdr *rtm, char *lim)
141 {
142 	struct if_announcemsghdr *ifan;
143 	struct ifinfo *ifi;
144 
145 	ifan = (struct if_announcemsghdr *)rtm;
146 	if ((char *)(ifan + 1) > lim)
147 		return (-1);
148 
149 	switch (ifan->ifan_what) {
150 	case IFAN_ARRIVAL:
151 		/*
152 		 * XXX for NetBSD 1.5, interface index will monotonically be
153 		 * increased as new pcmcia card gets inserted.
154 		 * we may be able to do a name-based interface match,
155 		 * and call ifreconfig() to enable the interface again.
156 		 */
157 		warnmsg(LOG_INFO, __func__,
158 		    "interface %s inserted", ifan->ifan_name);
159 		break;
160 	case IFAN_DEPARTURE:
161 		warnmsg(LOG_WARNING, __func__,
162 		    "interface %s removed", ifan->ifan_name);
163 		ifi = find_ifinfo(ifan->ifan_index);
164 		if (ifi) {
165 			if (dflag > 1) {
166 				warnmsg(LOG_INFO, __func__,
167 				    "bring interface %s to DOWN state",
168 				    ifan->ifan_name);
169 			}
170 			ifi->state = IFS_DOWN;
171 		}
172 		break;
173 	}
174 
175 	return (0);
176 }
177