1 /* external/dhcpcd/ifaddrs.c
2 **
3 ** Copyright 2011, The Android Open Source Project
4 **
5 ** Licensed under the Apache License, Version 2.0 (the "License");.
6 ** you may not use this file except in compliance with the License..
7 ** You may obtain a copy of the License at.
8 **
9 ** http://www.apache.org/licenses/LICENSE-2.0.
10 **
11 ** Unless required by applicable law or agreed to in writing, software.
12 ** distributed under the License is distributed on an "AS IS" BASIS,.
13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied..
14 ** See the License for the specific language governing permissions and.
15 ** limitations under the License.
16 */
17
18 #include <arpa/inet.h>
19 #include <sys/socket.h>
20 #include "ifaddrs.h"
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <unistd.h>
24 #include <sys/types.h>
25 #include <dirent.h>
26 #include <netinet/ether.h>
27 #include <netdb.h>
28 #include <linux/if_packet.h>
29 #include <netinet/if_ether.h>
30 #include <linux/if_arp.h>
31 #include <netutils/ifc.h>
32
get_interface(const char * name,sa_family_t family)33 struct ifaddrs *get_interface(const char *name, sa_family_t family)
34 {
35 unsigned addr, mask, flags;
36 struct ifaddrs *ifa;
37 struct sockaddr_in *saddr = NULL;
38 struct sockaddr_in *smask = NULL;
39 struct sockaddr_ll *hwaddr = NULL;
40 unsigned char hwbuf[ETH_ALEN];
41
42 if(ifc_get_info(name, &addr, &mask, &flags))
43 return NULL;
44
45 if ((family == AF_INET) && (addr == 0))
46 return NULL;
47
48 ifa = malloc(sizeof(struct ifaddrs));
49 if (!ifa)
50 return NULL;
51 memset(ifa, 0, sizeof(struct ifaddrs));
52
53 ifa->ifa_name = malloc(strlen(name)+1);
54 if (!ifa->ifa_name) {
55 free(ifa);
56 return NULL;
57 }
58 strcpy(ifa->ifa_name, name);
59 ifa->ifa_flags = flags;
60
61 if (family == AF_INET) {
62 saddr = malloc(sizeof(struct sockaddr_in));
63 if (saddr) {
64 saddr->sin_addr.s_addr = addr;
65 saddr->sin_family = family;
66 }
67 ifa->ifa_addr = (struct sockaddr *)saddr;
68
69 if (mask != 0) {
70 smask = malloc(sizeof(struct sockaddr_in));
71 if (smask) {
72 smask->sin_addr.s_addr = mask;
73 smask->sin_family = family;
74 }
75 }
76 ifa->ifa_netmask = (struct sockaddr *)smask;
77 } else if (family == AF_PACKET) {
78 if (!ifc_get_hwaddr(name, hwbuf)) {
79 hwaddr = malloc(sizeof(struct sockaddr_ll));
80 if (hwaddr) {
81 memset(hwaddr, 0, sizeof(struct sockaddr_ll));
82 hwaddr->sll_family = family;
83 /* hwaddr->sll_protocol = ETHERTYPE_IP; */
84 hwaddr->sll_hatype = ARPHRD_ETHER;
85 hwaddr->sll_halen = ETH_ALEN;
86 memcpy(hwaddr->sll_addr, hwbuf, ETH_ALEN);
87 }
88 }
89 ifa->ifa_addr = (struct sockaddr *)hwaddr;
90 ifa->ifa_netmask = (struct sockaddr *)smask;
91 }
92 return ifa;
93 }
94
getifaddrs(struct ifaddrs ** ifap)95 int getifaddrs(struct ifaddrs **ifap)
96 {
97 DIR *d;
98 struct dirent *de;
99 struct ifaddrs *ifa;
100 struct ifaddrs *ifah = NULL;
101
102 if (!ifap)
103 return -1;
104 *ifap = NULL;
105
106 if (ifc_init())
107 return -1;
108
109 d = opendir("/sys/class/net");
110 if (d == 0)
111 return -1;
112 while ((de = readdir(d))) {
113 if (de->d_name[0] == '.')
114 continue;
115 ifa = get_interface(de->d_name, AF_INET);
116 if (ifa != NULL) {
117 ifa->ifa_next = ifah;
118 ifah = ifa;
119 }
120 ifa = get_interface(de->d_name, AF_PACKET);
121 if (ifa != NULL) {
122 ifa->ifa_next = ifah;
123 ifah = ifa;
124 }
125 }
126 *ifap = ifah;
127 closedir(d);
128 ifc_close();
129 return 0;
130 }
131
freeifaddrs(struct ifaddrs * ifa)132 void freeifaddrs(struct ifaddrs *ifa)
133 {
134 struct ifaddrs *ifp;
135
136 while (ifa) {
137 ifp = ifa;
138 free(ifp->ifa_name);
139 if (ifp->ifa_addr)
140 free(ifp->ifa_addr);
141 if (ifp->ifa_netmask)
142 free(ifp->ifa_netmask);
143 ifa = ifa->ifa_next;
144 free(ifp);
145 }
146 }
147