1 /* $NetBSD: interfaceiter.c,v 1.5 2014/12/10 04:38:01 christos Exp $ */
2
3 /*
4 * Copyright (C) 2004, 2005, 2007, 2008, 2014 Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (C) 1999-2003 Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
12 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17 * PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 /* Id: interfaceiter.c,v 1.45 2008/12/01 03:51:47 marka Exp */
21
22 /*! \file */
23
24 #include <config.h>
25
26 #include <sys/types.h>
27 #include <sys/ioctl.h>
28 #ifdef HAVE_SYS_SOCKIO_H
29 #include <sys/sockio.h> /* Required for ifiter_ioctl.c. */
30 #endif
31
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <unistd.h>
35 #include <errno.h>
36
37 #include <isc/interfaceiter.h>
38 #include <isc/log.h>
39 #include <isc/magic.h>
40 #include <isc/mem.h>
41 #include <isc/msgs.h>
42 #include <isc/net.h>
43 #include <isc/print.h>
44 #include <isc/result.h>
45 #include <isc/strerror.h>
46 #include <isc/string.h>
47 #include <isc/types.h>
48 #include <isc/util.h>
49
50 /* Must follow <isc/net.h>. */
51 #ifdef HAVE_NET_IF6_H
52 #include <net/if6.h>
53 #endif
54 #include <net/if.h>
55
56 /* Common utility functions */
57
58 /*%
59 * Extract the network address part from a "struct sockaddr".
60 * \brief
61 * The address family is given explicitly
62 * instead of using src->sa_family, because the latter does not work
63 * for copying a network mask obtained by SIOCGIFNETMASK (it does
64 * not have a valid address family).
65 */
66
67 static void
get_addr(unsigned int family,isc_netaddr_t * dst,struct sockaddr * src,char * ifname)68 get_addr(unsigned int family, isc_netaddr_t *dst, struct sockaddr *src,
69 char *ifname)
70 {
71 struct sockaddr_in6 *sa6;
72
73 #if !defined(ISC_PLATFORM_HAVEIFNAMETOINDEX) || \
74 !defined(ISC_PLATFORM_HAVESCOPEID)
75 UNUSED(ifname);
76 #endif
77
78 /* clear any remaining value for safety */
79 memset(dst, 0, sizeof(*dst));
80
81 dst->family = family;
82 switch (family) {
83 case AF_INET:
84 memmove(&dst->type.in,
85 &((struct sockaddr_in *) src)->sin_addr,
86 sizeof(struct in_addr));
87 break;
88 case AF_INET6:
89 sa6 = (struct sockaddr_in6 *)src;
90 memmove(&dst->type.in6, &sa6->sin6_addr,
91 sizeof(struct in6_addr));
92 #ifdef ISC_PLATFORM_HAVESCOPEID
93 if (sa6->sin6_scope_id != 0)
94 isc_netaddr_setzone(dst, sa6->sin6_scope_id);
95 else {
96 /*
97 * BSD variants embed scope zone IDs in the 128bit
98 * address as a kernel internal form. Unfortunately,
99 * the embedded IDs are not hidden from applications
100 * when getting access to them by sysctl or ioctl.
101 * We convert the internal format to the pure address
102 * part and the zone ID part.
103 * Since multicast addresses should not appear here
104 * and they cannot be distinguished from netmasks,
105 * we only consider unicast link-local addresses.
106 */
107 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) {
108 isc_uint16_t zone16;
109
110 memmove(&zone16, &sa6->sin6_addr.s6_addr[2],
111 sizeof(zone16));
112 zone16 = ntohs(zone16);
113 if (zone16 != 0) {
114 /* the zone ID is embedded */
115 isc_netaddr_setzone(dst,
116 (isc_uint32_t)zone16);
117 dst->type.in6.s6_addr[2] = 0;
118 dst->type.in6.s6_addr[3] = 0;
119 #ifdef ISC_PLATFORM_HAVEIFNAMETOINDEX
120 } else if (ifname != NULL) {
121 unsigned int zone;
122
123 /*
124 * sin6_scope_id is still not provided,
125 * but the corresponding interface name
126 * is know. Use the interface ID as
127 * the link ID.
128 */
129 zone = if_nametoindex(ifname);
130 if (zone != 0) {
131 isc_netaddr_setzone(dst,
132 (isc_uint32_t)zone);
133 }
134 #endif
135 }
136 }
137 }
138 #endif
139 break;
140 default:
141 INSIST(0);
142 break;
143 }
144 }
145
146 /*
147 * Include system-dependent code.
148 */
149
150 #ifdef __linux
151 #define ISC_IF_INET6_SZ \
152 sizeof("00000000000000000000000000000001 01 80 10 80 XXXXXXloXXXXXXXX\n")
153 static isc_result_t linux_if_inet6_next(isc_interfaceiter_t *);
154 static isc_result_t linux_if_inet6_current(isc_interfaceiter_t *);
155 static void linux_if_inet6_first(isc_interfaceiter_t *iter);
156 #endif
157
158 #if HAVE_GETIFADDRS
159 #include "ifiter_getifaddrs.c"
160 #elif HAVE_IFLIST_SYSCTL
161 #include "ifiter_sysctl.c"
162 #else
163 #include "ifiter_ioctl.c"
164 #endif
165
166 #ifdef __linux
167 static void
linux_if_inet6_first(isc_interfaceiter_t * iter)168 linux_if_inet6_first(isc_interfaceiter_t *iter) {
169 if (iter->proc != NULL) {
170 rewind(iter->proc);
171 (void)linux_if_inet6_next(iter);
172 } else
173 iter->valid = ISC_R_NOMORE;
174 }
175
176 static isc_result_t
linux_if_inet6_next(isc_interfaceiter_t * iter)177 linux_if_inet6_next(isc_interfaceiter_t *iter) {
178 if (iter->proc != NULL &&
179 fgets(iter->entry, sizeof(iter->entry), iter->proc) != NULL)
180 iter->valid = ISC_R_SUCCESS;
181 else
182 iter->valid = ISC_R_NOMORE;
183 return (iter->valid);
184 }
185
186 static isc_result_t
linux_if_inet6_current(isc_interfaceiter_t * iter)187 linux_if_inet6_current(isc_interfaceiter_t *iter) {
188 char address[33];
189 char name[IF_NAMESIZE+1];
190 struct in6_addr addr6;
191 int ifindex, prefix, flag3, flag4;
192 int res;
193 unsigned int i;
194
195 if (iter->valid != ISC_R_SUCCESS)
196 return (iter->valid);
197 if (iter->proc == NULL) {
198 isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
199 ISC_LOGMODULE_INTERFACE, ISC_LOG_ERROR,
200 "/proc/net/if_inet6:iter->proc == NULL");
201 return (ISC_R_FAILURE);
202 }
203
204 res = sscanf(iter->entry, "%32[a-f0-9] %x %x %x %x %16s\n",
205 address, &ifindex, &prefix, &flag3, &flag4, name);
206 if (res != 6) {
207 isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
208 ISC_LOGMODULE_INTERFACE, ISC_LOG_ERROR,
209 "/proc/net/if_inet6:sscanf() -> %d (expected 6)",
210 res);
211 return (ISC_R_FAILURE);
212 }
213 if (strlen(address) != 32) {
214 isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
215 ISC_LOGMODULE_INTERFACE, ISC_LOG_ERROR,
216 "/proc/net/if_inet6:strlen(%s) != 32", address);
217 return (ISC_R_FAILURE);
218 }
219 for (i = 0; i < 16; i++) {
220 unsigned char byte;
221 static const char hex[] = "0123456789abcdef";
222 byte = ((strchr(hex, address[i * 2]) - hex) << 4) |
223 (strchr(hex, address[i * 2 + 1]) - hex);
224 addr6.s6_addr[i] = byte;
225 }
226 iter->current.af = AF_INET6;
227 iter->current.flags = INTERFACE_F_UP;
228 isc_netaddr_fromin6(&iter->current.address, &addr6);
229 if (isc_netaddr_islinklocal(&iter->current.address)) {
230 isc_netaddr_setzone(&iter->current.address,
231 (isc_uint32_t)ifindex);
232 }
233 for (i = 0; i < 16; i++) {
234 if (prefix > 8) {
235 addr6.s6_addr[i] = 0xff;
236 prefix -= 8;
237 } else {
238 addr6.s6_addr[i] = (0xff << (8 - prefix)) & 0xff;
239 prefix = 0;
240 }
241 }
242 isc_netaddr_fromin6(&iter->current.netmask, &addr6);
243 strncpy(iter->current.name, name, sizeof(iter->current.name));
244 return (ISC_R_SUCCESS);
245 }
246 #endif
247
248 /*
249 * The remaining code is common to the sysctl and ioctl case.
250 */
251
252 isc_result_t
isc_interfaceiter_current(isc_interfaceiter_t * iter,isc_interface_t * ifdata)253 isc_interfaceiter_current(isc_interfaceiter_t *iter,
254 isc_interface_t *ifdata)
255 {
256 REQUIRE(iter->result == ISC_R_SUCCESS);
257 memmove(ifdata, &iter->current, sizeof(*ifdata));
258 return (ISC_R_SUCCESS);
259 }
260
261 isc_result_t
isc_interfaceiter_first(isc_interfaceiter_t * iter)262 isc_interfaceiter_first(isc_interfaceiter_t *iter) {
263 isc_result_t result;
264
265 REQUIRE(VALID_IFITER(iter));
266
267 internal_first(iter);
268 for (;;) {
269 result = internal_current(iter);
270 if (result != ISC_R_IGNORE)
271 break;
272 result = internal_next(iter);
273 if (result != ISC_R_SUCCESS)
274 break;
275 }
276 iter->result = result;
277 return (result);
278 }
279
280 isc_result_t
isc_interfaceiter_next(isc_interfaceiter_t * iter)281 isc_interfaceiter_next(isc_interfaceiter_t *iter) {
282 isc_result_t result;
283
284 REQUIRE(VALID_IFITER(iter));
285 REQUIRE(iter->result == ISC_R_SUCCESS);
286
287 for (;;) {
288 result = internal_next(iter);
289 if (result != ISC_R_SUCCESS)
290 break;
291 result = internal_current(iter);
292 if (result != ISC_R_IGNORE)
293 break;
294 }
295 iter->result = result;
296 return (result);
297 }
298
299 void
isc_interfaceiter_destroy(isc_interfaceiter_t ** iterp)300 isc_interfaceiter_destroy(isc_interfaceiter_t **iterp)
301 {
302 isc_interfaceiter_t *iter;
303 REQUIRE(iterp != NULL);
304 iter = *iterp;
305 REQUIRE(VALID_IFITER(iter));
306
307 internal_destroy(iter);
308 if (iter->buf != NULL)
309 isc_mem_put(iter->mctx, iter->buf, iter->bufsize);
310
311 iter->magic = 0;
312 isc_mem_put(iter->mctx, iter, sizeof(*iter));
313 *iterp = NULL;
314 }
315