1 /* $KAME: getifaddrs.c,v 1.9 2001/08/20 02:31:20 itojun Exp $ */
4 * Copyright (c) 1995, 1999
5 * Berkeley Software Design, Inc. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * THIS SOFTWARE IS PROVIDED BY Berkeley Software Design, Inc. ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL Berkeley Software Design, Inc. BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * BSDI getifaddrs.c,v 2.12 2000/02/23 14:51:59 dab Exp
28 * NOTE: SIOCGIFCONF case is not LP64 friendly. it also does not perform
29 * try-and-error for region size.
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
35 #include "namespace.h"
36 #include <sys/types.h>
37 #include <sys/ioctl.h>
38 #include <sys/socket.h>
41 #include <sys/param.h>
42 #include <net/route.h>
43 #include <sys/sysctl.h>
44 #include <net/if_dl.h>
51 #include "un-namespace.h"
54 #define SA_LEN(sa) sizeof(struct sockaddr)
58 #define SA_LEN(sa) (sa)->sa_len
61 #define SALIGN (sizeof(long) - 1)
62 #define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : (SALIGN + 1))
66 * On systems with a routing socket, ALIGNBYTES should match the value
67 * that the kernel uses when building the messages.
69 #define ALIGNBYTES XXX
72 #define ALIGN(p) (((u_long)(p) + ALIGNBYTES) &~ ALIGNBYTES)
75 #define MAX_SYSCTL_TRY 5
78 getifaddrs(struct ifaddrs **pif)
88 struct ifaddrs *cif = 0;
90 struct rt_msghdr *rtm;
91 struct if_msghdrl *ifm;
92 struct ifa_msghdrl *ifam;
93 struct sockaddr_dl *dl;
95 struct ifaddrs *ifa, *ift;
96 struct if_data *if_data;
105 mib[2] = 0; /* protocol */
106 mib[3] = 0; /* wildcard address family */
107 mib[4] = NET_RT_IFLISTL;/* extra fields for extensible msghdr structs */
108 mib[5] = 0; /* no flags */
111 * We'll try to get addresses several times in case that
112 * the number of addresses is unexpectedly increased during
113 * the two sysctl calls. This should rarely happen, but we'll
114 * try to do our best for applications that assume success of
115 * this library (which should usually be the case).
116 * Portability note: since FreeBSD does not add margin of
117 * memory at the first sysctl, the possibility of failure on
118 * the second sysctl call is a bit higher.
121 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
123 if ((buf = malloc(needed)) == NULL)
125 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
126 if (errno != ENOMEM || ++ntry >= MAX_SYSCTL_TRY) {
133 } while (buf == NULL);
135 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
136 rtm = (struct rt_msghdr *)(void *)next;
137 if (rtm->rtm_version != RTM_VERSION)
139 switch (rtm->rtm_type) {
141 ifm = (struct if_msghdrl *)(void *)rtm;
142 if (ifm->ifm_addrs & RTA_IFP) {
143 idx = ifm->ifm_index;
145 if_data = IF_MSGHDRL_IFM_DATA(ifm);
146 dcnt += if_data->ifi_datalen;
147 dl = (struct sockaddr_dl *)IF_MSGHDRL_RTA(ifm);
148 dcnt += SA_RLEN((struct sockaddr *)(void*)dl) +
150 ncnt += dl->sdl_nlen + 1;
156 ifam = (struct ifa_msghdrl *)(void *)rtm;
157 if (idx && ifam->ifam_index != idx)
158 abort(); /* this cannot happen */
160 #define RTA_MASKS (RTA_NETMASK | RTA_IFA | RTA_BRD)
161 if (idx == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0)
163 p = (char *)IFA_MSGHDRL_RTA(ifam);
165 if_data = IFA_MSGHDRL_IFAM_DATA(ifam);
166 dcnt += if_data->ifi_datalen + ALIGNBYTES;
168 /* Scan to look for length of address */
170 for (p0 = p, i = 0; i < RTAX_MAX; i++) {
171 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
174 sa = (struct sockaddr *)(void *)p;
182 for (p = p0, i = 0; i < RTAX_MAX; i++) {
183 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
186 sa = (struct sockaddr *)(void *)p;
188 if (i == RTAX_NETMASK && SA_LEN(sa) == 0)
198 if (icnt + dcnt + ncnt == 1) {
203 data = malloc(sizeof(struct ifaddrs) * icnt + dcnt + ncnt);
209 ifa = (struct ifaddrs *)(void *)data;
210 data += sizeof(struct ifaddrs) * icnt;
213 memset(ifa, 0, sizeof(struct ifaddrs) * icnt);
217 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
218 rtm = (struct rt_msghdr *)(void *)next;
219 if (rtm->rtm_version != RTM_VERSION)
221 switch (rtm->rtm_type) {
223 ifm = (struct if_msghdrl *)(void *)rtm;
224 if ((ifm->ifm_addrs & RTA_IFP) == 0) {
229 idx = ifm->ifm_index;
230 dl = (struct sockaddr_dl *)IF_MSGHDRL_RTA(ifm);
233 ift->ifa_name = names;
234 ift->ifa_flags = (int)ifm->ifm_flags;
235 memcpy(names, dl->sdl_data, (size_t)dl->sdl_nlen);
236 names[dl->sdl_nlen] = 0;
237 names += dl->sdl_nlen + 1;
239 ift->ifa_addr = (struct sockaddr *)(void *)data;
240 memcpy(data, dl, (size_t)SA_LEN((struct sockaddr *)
242 data += SA_RLEN((struct sockaddr *)(void *)dl);
244 if_data = IF_MSGHDRL_IFM_DATA(ifm);
245 /* ifm_data needs to be aligned */
246 ift->ifa_data = data = (void *)ALIGN(data);
247 memcpy(data, if_data, if_data->ifi_datalen);
248 data += if_data->ifi_datalen;
250 ift = (ift->ifa_next = ift + 1);
254 ifam = (struct ifa_msghdrl *)(void *)rtm;
255 if (idx && ifam->ifam_index != idx)
256 abort(); /* this cannot happen */
258 if (idx == 0 || (ifam->ifam_addrs & RTA_MASKS) == 0)
260 ift->ifa_name = cif->ifa_name;
261 ift->ifa_flags = cif->ifa_flags;
262 ift->ifa_data = NULL;
264 p = (char *)IFA_MSGHDRL_RTA(ifam);
265 /* Scan to look for length of address */
267 for (p0 = p, i = 0; i < RTAX_MAX; i++) {
268 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
271 sa = (struct sockaddr *)(void *)p;
279 for (p = p0, i = 0; i < RTAX_MAX; i++) {
280 if ((RTA_MASKS & ifam->ifam_addrs & (1 << i))
283 sa = (struct sockaddr *)(void *)p;
288 (struct sockaddr *)(void *)data;
289 memcpy(data, p, len);
295 (struct sockaddr *)(void *)data;
296 if (SA_LEN(sa) == 0) {
297 memset(data, 0, alen);
301 memcpy(data, p, len);
307 (struct sockaddr *)(void *)data;
308 memcpy(data, p, len);
315 if_data = IFA_MSGHDRL_IFAM_DATA(ifam);
316 /* ifam_data needs to be aligned */
317 ift->ifa_data = data = (void *)ALIGN(data);
318 memcpy(data, if_data, if_data->ifi_datalen);
319 data += if_data->ifi_datalen;
321 ift = (ift->ifa_next = ift + 1);
329 ift->ifa_next = NULL;
339 freeifaddrs(struct ifaddrs *ifp)