1 /*
2 * dhcpcd - DHCP client daemon
3 * Copyright (c) 2006-2010 Roy Marples <roy@marples.name>
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 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include <sys/ioctl.h>
29 #include <sys/param.h>
30 #include <sys/socket.h>
31 #include <sys/stat.h>
32 #include <sys/sysctl.h>
33 #include <sys/types.h>
34
35 #include <arpa/inet.h>
36 #include <net/if.h>
37 #include <net/if_dl.h>
38 #include <net/route.h>
39 #include <netinet/in.h>
40 #ifdef __DragonFly__
41 # include <netproto/802_11/ieee80211_ioctl.h>
42 #elif __APPLE__
43 /* FIXME: Add apple includes so we can work out SSID */
44 #else
45 # include <net80211/ieee80211_ioctl.h>
46 #endif
47
48 #include <errno.h>
49 #include <fnmatch.h>
50 #include <stddef.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <syslog.h>
55 #include <unistd.h>
56
57 #include "config.h"
58 #include "common.h"
59 #include "configure.h"
60 #include "dhcp.h"
61 #include "if-options.h"
62 #include "net.h"
63
64 #define ROUNDUP(a) \
65 ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
66 #define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))
67
68 /* FIXME: Why do we need to check for sa_family 255 */
69 #define COPYOUT(sin, sa) \
70 sin.s_addr = ((sa) != NULL) ? \
71 (((struct sockaddr_in *)(void *)sa)->sin_addr).s_addr : 0
72
73 static int r_fd = -1;
74 static char *link_buf;
75 static ssize_t link_buflen;
76
77 int
if_init(_unused struct interface * iface)78 if_init(_unused struct interface *iface)
79 {
80 /* BSD promotes secondary address by default */
81 return 0;
82 }
83
84 int
if_conf(_unused struct interface * iface)85 if_conf(_unused struct interface *iface)
86 {
87 /* No extra checks needed on BSD */
88 return 0;
89 }
90
91 int
init_sockets(void)92 init_sockets(void)
93 {
94 if ((socket_afnet = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
95 return -1;
96 set_cloexec(socket_afnet);
97 if ((r_fd = socket(PF_ROUTE, SOCK_RAW, 0)) == -1)
98 return -1;
99 set_cloexec(r_fd);
100 return 0;
101 }
102
103 int
getifssid(const char * ifname,char * ssid)104 getifssid(const char *ifname, char *ssid)
105 {
106 int retval = -1;
107 #if defined(SIOCG80211NWID)
108 struct ifreq ifr;
109 struct ieee80211_nwid nwid;
110 #elif defined(IEEE80211_IOC_SSID)
111 struct ieee80211req ireq;
112 char nwid[IEEE80211_NWID_LEN + 1];
113 #endif
114
115 #if defined(SIOCG80211NWID) /* NetBSD */
116 memset(&ifr, 0, sizeof(ifr));
117 strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
118 memset(&nwid, 0, sizeof(nwid));
119 ifr.ifr_data = (void *)&nwid;
120 if (ioctl(socket_afnet, SIOCG80211NWID, &ifr) == 0) {
121 retval = nwid.i_len;
122 memcpy(ssid, nwid.i_nwid, nwid.i_len);
123 ssid[nwid.i_len] = '\0';
124 }
125 #elif defined(IEEE80211_IOC_SSID) /* FreeBSD */
126 memset(&ireq, 0, sizeof(ireq));
127 strlcpy(ireq.i_name, ifname, sizeof(ireq.i_name));
128 ireq.i_type = IEEE80211_IOC_SSID;
129 ireq.i_val = -1;
130 ireq.i_data = &nwid;
131 if (ioctl(socket_afnet, SIOCG80211, &ireq) == 0) {
132 retval = ireq.i_len;
133 memcpy(ssid, nwid, ireq.i_len);
134 ssid[ireq.i_len] = '\0';
135 }
136 #endif
137 return retval;
138 }
139
140 int
if_address(const struct interface * iface,const struct in_addr * address,const struct in_addr * netmask,const struct in_addr * broadcast,int action)141 if_address(const struct interface *iface, const struct in_addr *address,
142 const struct in_addr *netmask, const struct in_addr *broadcast,
143 int action)
144 {
145 int retval;
146 struct ifaliasreq ifa;
147 union {
148 struct sockaddr *sa;
149 struct sockaddr_in *sin;
150 } _s;
151
152 memset(&ifa, 0, sizeof(ifa));
153 strlcpy(ifa.ifra_name, iface->name, sizeof(ifa.ifra_name));
154
155 #define ADDADDR(_var, _addr) { \
156 _s.sa = &_var; \
157 _s.sin->sin_family = AF_INET; \
158 _s.sin->sin_len = sizeof(*_s.sin); \
159 memcpy(&_s.sin->sin_addr, _addr, sizeof(_s.sin->sin_addr)); \
160 }
161
162 ADDADDR(ifa.ifra_addr, address);
163 ADDADDR(ifa.ifra_mask, netmask);
164 if (action >= 0 && broadcast) {
165 ADDADDR(ifa.ifra_broadaddr, broadcast);
166 }
167 #undef ADDADDR
168
169 if (action < 0)
170 retval = ioctl(socket_afnet, SIOCDIFADDR, &ifa);
171 else
172 retval = ioctl(socket_afnet, SIOCAIFADDR, &ifa);
173 return retval;
174 }
175
176 /* ARGSUSED4 */
177 int
if_route(const struct interface * iface,const struct in_addr * dest,const struct in_addr * net,const struct in_addr * gate,_unused int metric,int action)178 if_route(const struct interface *iface, const struct in_addr *dest,
179 const struct in_addr *net, const struct in_addr *gate,
180 _unused int metric, int action)
181 {
182 union sockunion {
183 struct sockaddr sa;
184 struct sockaddr_in sin;
185 #ifdef INET6
186 struct sockaddr_in6 sin6;
187 #endif
188 struct sockaddr_dl sdl;
189 struct sockaddr_storage ss;
190 } su;
191 struct rtm
192 {
193 struct rt_msghdr hdr;
194 char buffer[sizeof(su) * 4];
195 } rtm;
196 char *bp = rtm.buffer, *p;
197 size_t l;
198 int retval = 0;
199
200 #define ADDSU(_su) { \
201 l = ROUNDUP(_su.sa.sa_len); \
202 memcpy(bp, &(_su), l); \
203 bp += l; \
204 }
205 #define ADDADDR(_a) { \
206 memset (&su, 0, sizeof(su)); \
207 su.sin.sin_family = AF_INET; \
208 su.sin.sin_len = sizeof(su.sin); \
209 memcpy (&su.sin.sin_addr, _a, sizeof(su.sin.sin_addr)); \
210 ADDSU(su); \
211 }
212
213 memset(&rtm, 0, sizeof(rtm));
214 rtm.hdr.rtm_version = RTM_VERSION;
215 rtm.hdr.rtm_seq = 1;
216 if (action == 0)
217 rtm.hdr.rtm_type = RTM_CHANGE;
218 else if (action > 0)
219 rtm.hdr.rtm_type = RTM_ADD;
220 else
221 rtm.hdr.rtm_type = RTM_DELETE;
222 rtm.hdr.rtm_flags = RTF_UP;
223 /* None interface subnet routes are static. */
224 if (gate->s_addr != INADDR_ANY ||
225 net->s_addr != iface->net.s_addr ||
226 dest->s_addr != (iface->addr.s_addr & iface->net.s_addr))
227 rtm.hdr.rtm_flags |= RTF_STATIC;
228 rtm.hdr.rtm_addrs = RTA_DST | RTA_GATEWAY;
229 if (dest->s_addr == gate->s_addr && net->s_addr == INADDR_BROADCAST)
230 rtm.hdr.rtm_flags |= RTF_HOST;
231 else {
232 rtm.hdr.rtm_addrs |= RTA_NETMASK;
233 if (rtm.hdr.rtm_flags & RTF_STATIC)
234 rtm.hdr.rtm_flags |= RTF_GATEWAY;
235 if (action >= 0)
236 rtm.hdr.rtm_addrs |= RTA_IFA;
237 }
238
239 ADDADDR(dest);
240 if (rtm.hdr.rtm_flags & RTF_HOST ||
241 !(rtm.hdr.rtm_flags & RTF_STATIC))
242 {
243 /* Make us a link layer socket for the host gateway */
244 memset(&su, 0, sizeof(su));
245 su.sdl.sdl_len = sizeof(struct sockaddr_dl);
246 link_addr(iface->name, &su.sdl);
247 ADDSU(su);
248 } else
249 ADDADDR(gate);
250
251 if (rtm.hdr.rtm_addrs & RTA_NETMASK) {
252 /* Ensure that netmask is set correctly */
253 memset(&su, 0, sizeof(su));
254 su.sin.sin_family = AF_INET;
255 su.sin.sin_len = sizeof(su.sin);
256 memcpy(&su.sin.sin_addr, &net->s_addr, sizeof(su.sin.sin_addr));
257 p = su.sa.sa_len + (char *)&su;
258 for (su.sa.sa_len = 0; p > (char *)&su;)
259 if (*--p != 0) {
260 su.sa.sa_len = 1 + p - (char *)&su;
261 break;
262 }
263 ADDSU(su);
264 }
265
266 if (rtm.hdr.rtm_addrs & RTA_IFA)
267 ADDADDR(&iface->addr);
268
269 rtm.hdr.rtm_msglen = l = bp - (char *)&rtm;
270 if (write(r_fd, &rtm, l) == -1)
271 retval = -1;
272 return retval;
273 }
274
275 int
open_link_socket(void)276 open_link_socket(void)
277 {
278 int fd;
279
280 fd = socket(PF_ROUTE, SOCK_RAW, 0);
281 if (fd != -1) {
282 set_cloexec(fd);
283 set_nonblock(fd);
284 }
285 return fd;
286 }
287
288 static void
get_addrs(int type,char * cp,struct sockaddr ** sa)289 get_addrs(int type, char *cp, struct sockaddr **sa)
290 {
291 int i;
292
293 for (i = 0; i < RTAX_MAX; i++) {
294 if (type & (1 << i)) {
295 sa[i] = (struct sockaddr *)cp;
296 #ifdef DEBUG
297 printf ("got %d %d %s\n", i, sa[i]->sa_family,
298 inet_ntoa(((struct sockaddr_in *)sa[i])->
299 sin_addr));
300 #endif
301 ADVANCE(cp, sa[i]);
302 } else
303 sa[i] = NULL;
304 }
305 }
306
307 int
manage_link(int fd)308 manage_link(int fd)
309 {
310 char *p, *e, *cp;
311 char ifname[IF_NAMESIZE];
312 ssize_t bytes;
313 struct rt_msghdr *rtm;
314 struct if_announcemsghdr *ifan;
315 struct if_msghdr *ifm;
316 struct ifa_msghdr *ifam;
317 struct rt rt;
318 struct sockaddr *sa, *rti_info[RTAX_MAX];
319 int len;
320 #ifdef RTM_CHGADDR
321 struct sockaddr_dl sdl;
322 unsigned char *hwaddr;
323 #endif
324
325 for (;;) {
326 if (ioctl(fd, FIONREAD, &len) == -1)
327 return -1;
328 if (link_buflen < len) {
329 p = realloc(link_buf, len);
330 if (p == NULL)
331 return -1;
332 link_buf = p;
333 link_buflen = len;
334 }
335 bytes = read(fd, link_buf, link_buflen);
336 if (bytes == -1) {
337 if (errno == EAGAIN)
338 return 0;
339 if (errno == EINTR)
340 continue;
341 return -1;
342 }
343 e = link_buf + bytes;
344 for (p = link_buf; p < e; p += rtm->rtm_msglen) {
345 rtm = (struct rt_msghdr *)(void *)p;
346 switch(rtm->rtm_type) {
347 #ifdef RTM_IFANNOUNCE
348 case RTM_IFANNOUNCE:
349 ifan = (struct if_announcemsghdr *)(void *)p;
350 switch(ifan->ifan_what) {
351 case IFAN_ARRIVAL:
352 handle_interface(1, ifan->ifan_name);
353 break;
354 case IFAN_DEPARTURE:
355 handle_interface(-1, ifan->ifan_name);
356 break;
357 }
358 break;
359 #endif
360 case RTM_IFINFO:
361 ifm = (struct if_msghdr *)(void *)p;
362 memset(ifname, 0, sizeof(ifname));
363 if (if_indextoname(ifm->ifm_index, ifname))
364 handle_interface(0, ifname);
365 break;
366 case RTM_DELETE:
367 if (!(rtm->rtm_addrs & RTA_DST) ||
368 !(rtm->rtm_addrs & RTA_GATEWAY) ||
369 !(rtm->rtm_addrs & RTA_NETMASK))
370 break;
371 if (rtm->rtm_pid == getpid())
372 break;
373 cp = (char *)(void *)(rtm + 1);
374 sa = (struct sockaddr *)(void *)cp;
375 if (sa->sa_family != AF_INET)
376 break;
377 get_addrs(rtm->rtm_addrs, cp, rti_info);
378 rt.iface = NULL;
379 rt.next = NULL;
380 COPYOUT(rt.dest, rti_info[RTAX_DST]);
381 COPYOUT(rt.net, rti_info[RTAX_NETMASK]);
382 COPYOUT(rt.gate, rti_info[RTAX_GATEWAY]);
383 route_deleted(&rt);
384 break;
385 #ifdef RTM_CHGADDR
386 case RTM_CHGADDR: /* FALLTHROUGH */
387 #endif
388 case RTM_DELADDR: /* FALLTHROUGH */
389 case RTM_NEWADDR:
390 ifam = (struct ifa_msghdr *)(void *)p;
391 if (!if_indextoname(ifam->ifam_index, ifname))
392 break;
393 cp = (char *)(void *)(ifam + 1);
394 get_addrs(ifam->ifam_addrs, cp, rti_info);
395 if (rti_info[RTAX_IFA] == NULL)
396 break;
397 switch (rti_info[RTAX_IFA]->sa_family) {
398 #ifdef RTM_CHGADDR
399 case AF_LINK:
400 if (rtm->rtm_type != RTM_CHGADDR)
401 break;
402 memcpy(&sdl, rti_info[RTAX_IFA],
403 rti_info[RTAX_IFA]->sa_len);
404 hwaddr = xmalloc(sdl.sdl_alen);
405 memcpy(hwaddr, LLADDR(&sdl),
406 sdl.sdl_alen);
407 handle_hwaddr(ifname, hwaddr,
408 sdl.sdl_alen);
409 break;
410 #endif
411 case AF_INET:
412 case 255: /* FIXME: Why 255? */
413 COPYOUT(rt.dest, rti_info[RTAX_IFA]);
414 COPYOUT(rt.net, rti_info[RTAX_NETMASK]);
415 COPYOUT(rt.gate, rti_info[RTAX_BRD]);
416 handle_ifa(rtm->rtm_type, ifname,
417 &rt.dest, &rt.net, &rt.gate);
418 break;
419 }
420 break;
421 }
422 }
423 }
424 }
425