xref: /freebsd/usr.sbin/rtsold/if.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*	$KAME: if.c,v 1.27 2003/10/05 00:09:36 itojun Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  * Copyright (C) 1995, 1996, 1997, and 1998 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/ioctl.h>
37 #include <sys/queue.h>
38 #include <sys/socket.h>
39 #include <sys/sysctl.h>
40 
41 #include <net/if.h>
42 #include <net/if_types.h>
43 #include <net/route.h>
44 #include <net/if_dl.h>
45 #include <net/if_media.h>
46 #include <net/ethernet.h>
47 #include <netinet/in.h>
48 #include <netinet/icmp6.h>
49 
50 #include <netinet6/in6_var.h>
51 #include <netinet6/nd6.h>
52 
53 #include <capsicum_helpers.h>
54 #include <stdio.h>
55 #include <unistd.h>
56 #include <stdlib.h>
57 #include <syslog.h>
58 #include <string.h>
59 #include <fcntl.h>
60 #include <errno.h>
61 #include <limits.h>
62 #include <ifaddrs.h>
63 #include "rtsold.h"
64 
65 static int ifsock;
66 static void get_rtaddrs(int, struct sockaddr *, struct sockaddr **);
67 
68 int
69 ifinit(void)
70 {
71 	cap_rights_t rights;
72 	int sock;
73 
74 	sock = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
75 	if (sock < 0) {
76 		warnmsg(LOG_ERR, __func__, "socket(): %s",
77 		    strerror(errno));
78 		return (-1);
79 	}
80 	if (caph_rights_limit(sock, cap_rights_init(&rights, CAP_IOCTL)) < 0) {
81 		warnmsg(LOG_ERR, __func__, "caph_rights_limit(): %s",
82 		    strerror(errno));
83 		(void)close(sock);
84 		return (-1);
85 	}
86 	ifsock = sock;
87 	return (0);
88 }
89 
90 int
91 interface_up(char *name)
92 {
93 	struct ifreq ifr;
94 	struct in6_ndireq nd;
95 	int llflag;
96 	int s;
97 
98 	memset(&ifr, 0, sizeof(ifr));
99 	strlcpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
100 	memset(&nd, 0, sizeof(nd));
101 	strlcpy(nd.ifname, name, sizeof(nd.ifname));
102 
103 	if (ioctl(ifsock, SIOCGIFFLAGS, (caddr_t)&ifr) < 0) {
104 		warnmsg(LOG_WARNING, __func__, "ioctl(SIOCGIFFLAGS): %s",
105 		    strerror(errno));
106 		return (-1);
107 	}
108 	if (!(ifr.ifr_flags & IFF_UP)) {
109 		ifr.ifr_flags |= IFF_UP;
110 		if (ioctl(ifsock, SIOCSIFFLAGS, (caddr_t)&ifr) < 0)
111 			warnmsg(LOG_ERR, __func__,
112 			    "ioctl(SIOCSIFFLAGS): %s", strerror(errno));
113 		return (-1);
114 	}
115 	if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
116 		warnmsg(LOG_WARNING, __func__, "socket(AF_INET6, SOCK_DGRAM): %s",
117 		    strerror(errno));
118 		return (-1);
119 	}
120 	if (ioctl(s, SIOCGIFINFO_IN6, (caddr_t)&nd) < 0) {
121 		warnmsg(LOG_WARNING, __func__, "ioctl(SIOCGIFINFO_IN6): %s",
122 		    strerror(errno));
123 		close(s);
124 		return (-1);
125 	}
126 
127 	warnmsg(LOG_DEBUG, __func__, "checking if %s is ready...", name);
128 
129 	if (nd.ndi.flags & ND6_IFF_IFDISABLED) {
130 		if (Fflag) {
131 			nd.ndi.flags &= ~ND6_IFF_IFDISABLED;
132 			if (ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&nd)) {
133 				warnmsg(LOG_WARNING, __func__,
134 				    "ioctl(SIOCSIFINFO_IN6): %s",
135 		    		    strerror(errno));
136 				close(s);
137 				return (-1);
138 			}
139 		} else {
140 			warnmsg(LOG_WARNING, __func__,
141 			    "%s is disabled.", name);
142 			close(s);
143 			return (-1);
144 		}
145 	}
146 	if (!(nd.ndi.flags & ND6_IFF_ACCEPT_RTADV)) {
147 		if (Fflag) {
148 			nd.ndi.flags |= ND6_IFF_ACCEPT_RTADV;
149 			if (ioctl(s, SIOCSIFINFO_IN6, (caddr_t)&nd)) {
150 				warnmsg(LOG_WARNING, __func__,
151 				    "ioctl(SIOCSIFINFO_IN6): %s",
152 		    		    strerror(errno));
153 				close(s);
154 				return (-1);
155 			}
156 		} else {
157 			warnmsg(LOG_WARNING, __func__,
158 			    "%s does not accept Router Advertisement.", name);
159 			close(s);
160 			return (-1);
161 		}
162 	}
163 	close(s);
164 
165 	if (cap_llflags_get(capllflags, name, &llflag) != 0) {
166 		warnmsg(LOG_WARNING, __func__,
167 		    "cap_llflags_get() failed, anyway I'll try");
168 		return (0);
169 	}
170 
171 	if (!(llflag & IN6_IFF_NOTREADY)) {
172 		warnmsg(LOG_DEBUG, __func__, "%s is ready", name);
173 		return (0);
174 	} else {
175 		if (llflag & IN6_IFF_TENTATIVE) {
176 			warnmsg(LOG_DEBUG, __func__, "%s is tentative",
177 			    name);
178 			return (IFS_TENTATIVE);
179 		}
180 		if (llflag & IN6_IFF_DUPLICATED)
181 			warnmsg(LOG_DEBUG, __func__, "%s is duplicated",
182 			    name);
183 		return (-1);
184 	}
185 }
186 
187 int
188 interface_status(struct ifinfo *ifinfo)
189 {
190 	char *ifname = ifinfo->ifname;
191 	struct ifreq ifr;
192 	struct ifmediareq ifmr;
193 
194 	/* get interface flags */
195 	memset(&ifr, 0, sizeof(ifr));
196 	strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
197 	if (ioctl(ifsock, SIOCGIFFLAGS, &ifr) < 0) {
198 		warnmsg(LOG_ERR, __func__, "ioctl(SIOCGIFFLAGS) on %s: %s",
199 		    ifname, strerror(errno));
200 		return (-1);
201 	}
202 	/*
203 	 * if one of UP and RUNNING flags is dropped,
204 	 * the interface is not active.
205 	 */
206 	if ((ifr.ifr_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
207 		goto inactive;
208 	/* Next, check carrier on the interface, if possible */
209 	if (!ifinfo->mediareqok)
210 		goto active;
211 	memset(&ifmr, 0, sizeof(ifmr));
212 	strlcpy(ifmr.ifm_name, ifname, sizeof(ifmr.ifm_name));
213 
214 	if (ioctl(ifsock, SIOCGIFMEDIA, (caddr_t)&ifmr) < 0) {
215 		if (errno != EINVAL) {
216 			warnmsg(LOG_DEBUG, __func__,
217 			    "ioctl(SIOCGIFMEDIA) on %s: %s",
218 			    ifname, strerror(errno));
219 			return(-1);
220 		}
221 		/*
222 		 * EINVAL simply means that the interface does not support
223 		 * the SIOCGIFMEDIA ioctl. We regard it alive.
224 		 */
225 		ifinfo->mediareqok = 0;
226 		goto active;
227 	}
228 
229 	if (ifmr.ifm_status & IFM_AVALID) {
230 		switch (ifmr.ifm_active & IFM_NMASK) {
231 		case IFM_ETHER:
232 		case IFM_IEEE80211:
233 			if (ifmr.ifm_status & IFM_ACTIVE)
234 				goto active;
235 			else
236 				goto inactive;
237 			break;
238 		default:
239 			goto inactive;
240 		}
241 	}
242 
243   inactive:
244 	return (0);
245 
246   active:
247 	return (1);
248 }
249 
250 #define ROUNDUP(a, size) \
251 	(((a) & ((size)-1)) ? (1 + ((a) | ((size)-1))) : (a))
252 
253 #define NEXT_SA(ap) (ap) = (struct sockaddr *) \
254 	((caddr_t)(ap) + ((ap)->sa_len ? ROUNDUP((ap)->sa_len,\
255 	sizeof(u_long)) : sizeof(u_long)))
256 #define ROUNDUP8(a) (1 + (((a) - 1) | 7))
257 
258 int
259 lladdropt_length(struct sockaddr_dl *sdl)
260 {
261 	switch (sdl->sdl_type) {
262 	case IFT_ETHER:
263 	case IFT_L2VLAN:
264 		return (ROUNDUP8(ETHER_ADDR_LEN + 2));
265 	default:
266 		return (0);
267 	}
268 }
269 
270 void
271 lladdropt_fill(struct sockaddr_dl *sdl, struct nd_opt_hdr *ndopt)
272 {
273 	char *addr;
274 
275 	ndopt->nd_opt_type = ND_OPT_SOURCE_LINKADDR; /* fixed */
276 
277 	switch (sdl->sdl_type) {
278 	case IFT_ETHER:
279 	case IFT_L2VLAN:
280 		ndopt->nd_opt_len = (ROUNDUP8(ETHER_ADDR_LEN + 2)) >> 3;
281 		addr = (char *)(ndopt + 1);
282 		memcpy(addr, LLADDR(sdl), ETHER_ADDR_LEN);
283 		break;
284 	default:
285 		warnmsg(LOG_ERR, __func__,
286 		    "unsupported link type(%d)", sdl->sdl_type);
287 		exit(1);
288 	}
289 }
290 
291 struct sockaddr_dl *
292 if_nametosdl(char *name)
293 {
294 	int mib[] = {CTL_NET, AF_ROUTE, 0, 0, NET_RT_IFLIST, 0};
295 	char *buf, *next, *lim;
296 	size_t len;
297 	struct if_msghdr *ifm;
298 	struct sockaddr *sa, *rti_info[RTAX_MAX];
299 	struct sockaddr_dl *sdl = NULL, *ret_sdl;
300 
301 	if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) < 0)
302 		return(NULL);
303 	if ((buf = malloc(len)) == NULL)
304 		return(NULL);
305 	if (sysctl(mib, nitems(mib), buf, &len, NULL, 0) < 0) {
306 		free(buf);
307 		return (NULL);
308 	}
309 
310 	lim = buf + len;
311 	for (next = buf; next < lim; next += ifm->ifm_msglen) {
312 		ifm = (struct if_msghdr *)(void *)next;
313 		if (ifm->ifm_type == RTM_IFINFO) {
314 			sa = (struct sockaddr *)(ifm + 1);
315 			get_rtaddrs(ifm->ifm_addrs, sa, rti_info);
316 			if ((sa = rti_info[RTAX_IFP]) != NULL) {
317 				if (sa->sa_family == AF_LINK) {
318 					sdl = (struct sockaddr_dl *)(void *)sa;
319 					if (strlen(name) != sdl->sdl_nlen)
320 						continue; /* not same len */
321 					if (strncmp(&sdl->sdl_data[0],
322 						    name,
323 						    sdl->sdl_nlen) == 0) {
324 						break;
325 					}
326 				}
327 			}
328 		}
329 	}
330 	if (next >= lim) {
331 		/* search failed */
332 		free(buf);
333 		return (NULL);
334 	}
335 
336 	if ((ret_sdl = malloc(sdl->sdl_len)) == NULL) {
337 		free(buf);
338 		return (NULL);
339 	}
340 	memcpy((caddr_t)ret_sdl, (caddr_t)sdl, sdl->sdl_len);
341 
342 	free(buf);
343 	return (ret_sdl);
344 }
345 
346 static void
347 get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info)
348 {
349 	int i;
350 
351 	for (i = 0; i < RTAX_MAX; i++) {
352 		if (addrs & (1 << i)) {
353 			rti_info[i] = sa;
354 			NEXT_SA(sa);
355 		} else
356 			rti_info[i] = NULL;
357 	}
358 }
359