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 <sys/cdefs.h>
30 #include "namespace.h"
31 #include <sys/param.h>
32 #include <sys/sysctl.h>
33 #include <sys/ioctl.h>
34 #include <sys/socket.h>
35 #include <net/if.h>
36 #include <net/if_dl.h>
37 #include <net/route.h>
38
39 #include <errno.h>
40 #include <ifaddrs.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include "un-namespace.h"
44
45 #define SALIGN (sizeof(long) - 1)
46 #define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : \
47 (SALIGN + 1))
48 #define MAX_SYSCTL_TRY 5
49 #define RTA_MASKS (RTA_GATEWAY | RTA_IFP | RTA_IFA)
50
51 int
getifmaddrs(struct ifmaddrs ** pif)52 getifmaddrs(struct ifmaddrs **pif)
53 {
54 int icnt = 1;
55 int dcnt = 0;
56 int ntry = 0;
57 size_t len;
58 size_t needed;
59 int mib[6];
60 int i;
61 char *buf;
62 char *data;
63 char *next;
64 char *p;
65 struct ifma_msghdr *ifmam;
66 struct ifmaddrs *ifa, *ift;
67 struct rt_msghdr *rtm;
68 struct sockaddr *sa;
69
70 mib[0] = CTL_NET;
71 mib[1] = PF_ROUTE;
72 mib[2] = 0; /* protocol */
73 mib[3] = 0; /* wildcard address family */
74 mib[4] = NET_RT_IFMALIST;
75 mib[5] = 0; /* no flags */
76 do {
77 if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
78 return (-1);
79 if ((buf = malloc(needed)) == NULL)
80 return (-1);
81 if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
82 if (errno != ENOMEM || ++ntry >= MAX_SYSCTL_TRY) {
83 free(buf);
84 return (-1);
85 }
86 free(buf);
87 buf = NULL;
88 }
89 } while (buf == NULL);
90
91 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
92 rtm = (struct rt_msghdr *)(void *)next;
93 if (rtm->rtm_version != RTM_VERSION)
94 continue;
95 switch (rtm->rtm_type) {
96 case RTM_NEWMADDR:
97 ifmam = (struct ifma_msghdr *)(void *)rtm;
98 if ((ifmam->ifmam_addrs & RTA_IFA) == 0)
99 break;
100 icnt++;
101 p = (char *)(ifmam + 1);
102 for (i = 0; i < RTAX_MAX; i++) {
103 if ((RTA_MASKS & ifmam->ifmam_addrs &
104 (1 << i)) == 0)
105 continue;
106 sa = (struct sockaddr *)(void *)p;
107 len = SA_RLEN(sa);
108 dcnt += len;
109 p += len;
110 }
111 break;
112 }
113 }
114
115 data = malloc(sizeof(struct ifmaddrs) * icnt + dcnt);
116 if (data == NULL) {
117 free(buf);
118 return (-1);
119 }
120
121 ifa = (struct ifmaddrs *)(void *)data;
122 data += sizeof(struct ifmaddrs) * icnt;
123
124 memset(ifa, 0, sizeof(struct ifmaddrs) * icnt);
125 ift = ifa;
126
127 for (next = buf; next < buf + needed; next += rtm->rtm_msglen) {
128 rtm = (struct rt_msghdr *)(void *)next;
129 if (rtm->rtm_version != RTM_VERSION)
130 continue;
131
132 switch (rtm->rtm_type) {
133 case RTM_NEWMADDR:
134 ifmam = (struct ifma_msghdr *)(void *)rtm;
135 if ((ifmam->ifmam_addrs & RTA_IFA) == 0)
136 break;
137
138 p = (char *)(ifmam + 1);
139 for (i = 0; i < RTAX_MAX; i++) {
140 if ((RTA_MASKS & ifmam->ifmam_addrs &
141 (1 << i)) == 0)
142 continue;
143 sa = (struct sockaddr *)(void *)p;
144 len = SA_RLEN(sa);
145 switch (i) {
146 case RTAX_GATEWAY:
147 ift->ifma_lladdr =
148 (struct sockaddr *)(void *)data;
149 memcpy(data, p, len);
150 data += len;
151 break;
152
153 case RTAX_IFP:
154 ift->ifma_name =
155 (struct sockaddr *)(void *)data;
156 memcpy(data, p, len);
157 data += len;
158 break;
159
160 case RTAX_IFA:
161 ift->ifma_addr =
162 (struct sockaddr *)(void *)data;
163 memcpy(data, p, len);
164 data += len;
165 break;
166
167 default:
168 data += len;
169 break;
170 }
171 p += len;
172 }
173 ift->ifma_next = ift + 1;
174 ift = ift->ifma_next;
175 break;
176 }
177 }
178
179 free(buf);
180
181 if (ift > ifa) {
182 ift--;
183 ift->ifma_next = NULL;
184 *pif = ifa;
185 } else {
186 *pif = NULL;
187 free(ifa);
188 }
189 return (0);
190 }
191
192 void
freeifmaddrs(struct ifmaddrs * ifmp)193 freeifmaddrs(struct ifmaddrs *ifmp)
194 {
195
196 free(ifmp);
197 }
198