1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2003 Bruce M. Simpson.
5 * All rights reserved
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include "namespace.h"
30 #include <sys/param.h>
31 #include <sys/sysctl.h>
32 #include <sys/ioctl.h>
33 #include <sys/socket.h>
34 #include <net/if.h>
35 #include <net/if_dl.h>
36 #include <net/route.h>
37
38 #include <errno.h>
39 #include <ifaddrs.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include "un-namespace.h"
43
44 #define SALIGN (sizeof(long) - 1)
45 #define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : \
46 (SALIGN + 1))
47 #define MAX_SYSCTL_TRY 5
48 #define RTA_MASKS (RTA_GATEWAY | RTA_IFP | RTA_IFA)
49
50 int
getifmaddrs(struct ifmaddrs ** pif)51 getifmaddrs(struct ifmaddrs **pif)
52 {
53 int icnt = 1;
54 int dcnt = 0;
55 int ntry = 0;
56 size_t len;
57 size_t needed;
58 int mib[6];
59 int i;
60 char *buf;
61 char *data;
62 char *next;
63 char *p;
64 struct ifma_msghdr *ifmam;
65 struct ifmaddrs *ifa, *ift;
66 struct rt_msghdr *rtm;
67 struct sockaddr *sa;
68
69 mib[0] = CTL_NET;
70 mib[1] = PF_ROUTE;
71 mib[2] = 0; /* protocol */
72 mib[3] = 0; /* wildcard address family */
73 mib[4] = NET_RT_IFMALIST;
74 mib[5] = 0; /* no flags */
75 do {
76 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
77 return (-1);
78 if ((buf = malloc(needed)) == NULL)
79 return (-1);
80 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
81 if (errno != ENOMEM || ++ntry >= MAX_SYSCTL_TRY) {
82 free(buf);
83 return (-1);
84 }
85 free(buf);
86 buf = NULL;
87 }
88 } while (buf == NULL);
89
90 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
91 rtm = (struct rt_msghdr *)(void *)next;
92 if (rtm->rtm_version != RTM_VERSION)
93 continue;
94 switch (rtm->rtm_type) {
95 case RTM_NEWMADDR:
96 ifmam = (struct ifma_msghdr *)(void *)rtm;
97 if ((ifmam->ifmam_addrs & RTA_IFA) == 0)
98 break;
99 icnt++;
100 p = (char *)(ifmam + 1);
101 for (i = 0; i < RTAX_MAX; i++) {
102 if ((RTA_MASKS & ifmam->ifmam_addrs &
103 (1 << i)) == 0)
104 continue;
105 sa = (struct sockaddr *)(void *)p;
106 len = SA_RLEN(sa);
107 dcnt += len;
108 p += len;
109 }
110 break;
111 }
112 }
113
114 data = malloc(sizeof(struct ifmaddrs) * icnt + dcnt);
115 if (data == NULL) {
116 free(buf);
117 return (-1);
118 }
119
120 ifa = (struct ifmaddrs *)(void *)data;
121 data += sizeof(struct ifmaddrs) * icnt;
122
123 memset(ifa, 0, sizeof(struct ifmaddrs) * icnt);
124 ift = ifa;
125
126 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
127 rtm = (struct rt_msghdr *)(void *)next;
128 if (rtm->rtm_version != RTM_VERSION)
129 continue;
130
131 switch (rtm->rtm_type) {
132 case RTM_NEWMADDR:
133 ifmam = (struct ifma_msghdr *)(void *)rtm;
134 if ((ifmam->ifmam_addrs & RTA_IFA) == 0)
135 break;
136
137 p = (char *)(ifmam + 1);
138 for (i = 0; i < RTAX_MAX; i++) {
139 if ((RTA_MASKS & ifmam->ifmam_addrs &
140 (1 << i)) == 0)
141 continue;
142 sa = (struct sockaddr *)(void *)p;
143 len = SA_RLEN(sa);
144 switch (i) {
145 case RTAX_GATEWAY:
146 ift->ifma_lladdr =
147 (struct sockaddr *)(void *)data;
148 memcpy(data, p, len);
149 data += len;
150 break;
151
152 case RTAX_IFP:
153 ift->ifma_name =
154 (struct sockaddr *)(void *)data;
155 memcpy(data, p, len);
156 data += len;
157 break;
158
159 case RTAX_IFA:
160 ift->ifma_addr =
161 (struct sockaddr *)(void *)data;
162 memcpy(data, p, len);
163 data += len;
164 break;
165
166 default:
167 data += len;
168 break;
169 }
170 p += len;
171 }
172 ift->ifma_next = ift + 1;
173 ift = ift->ifma_next;
174 break;
175 }
176 }
177
178 free(buf);
179
180 if (ift > ifa) {
181 ift--;
182 ift->ifma_next = NULL;
183 *pif = ifa;
184 } else {
185 *pif = NULL;
186 free(ifa);
187 }
188 return (0);
189 }
190
191 void
freeifmaddrs(struct ifmaddrs * ifmp)192 freeifmaddrs(struct ifmaddrs *ifmp)
193 {
194
195 free(ifmp);
196 }
197