remove trailing whitespace
[people/mcb30/busybox.git] / networking / nameif.c
1 /* vi: set sw=4 ts=4: */
2 /*
3  * nameif.c - Naming Interfaces based on MAC address for busybox.
4  *
5  * Written 2000 by Andi Kleen.
6  * Busybox port 2002 by Nick Fedchik <nick@fedchik.org.ua>
7  *                      Glenn McGrath
8  *
9  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
10  */
11
12 #include "libbb.h"
13 #include <syslog.h>
14 #include <net/if.h>
15 #include <netinet/ether.h>
16
17
18 /* Older versions of net/if.h do not appear to define IF_NAMESIZE. */
19 #ifndef IF_NAMESIZE
20 #  ifdef IFNAMSIZ
21 #    define IF_NAMESIZE IFNAMSIZ
22 #  else
23 #    define IF_NAMESIZE 16
24 #  endif
25 #endif
26
27 /* take from linux/sockios.h */
28 #define SIOCSIFNAME     0x8923  /* set interface name */
29
30 /* Octets in one Ethernet addr, from <linux/if_ether.h> */
31 #define ETH_ALEN        6
32
33 #ifndef ifr_newname
34 #define ifr_newname ifr_ifru.ifru_slave
35 #endif
36
37 typedef struct mactable_s {
38         struct mactable_s *next;
39         struct mactable_s *prev;
40         char *ifname;
41         struct ether_addr *mac;
42 } mactable_t;
43
44 /* Check ascii str_macaddr, convert and copy to *mac */
45 static struct ether_addr *cc_macaddr(const char *str_macaddr)
46 {
47         struct ether_addr *lmac, *mac;
48
49         lmac = ether_aton(str_macaddr);
50         if (lmac == NULL)
51                 bb_error_msg_and_die("cannot parse MAC %s", str_macaddr);
52         mac = xmalloc(ETH_ALEN);
53         memcpy(mac, lmac, ETH_ALEN);
54
55         return mac;
56 }
57
58 int nameif_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
59 int nameif_main(int argc, char **argv)
60 {
61         mactable_t *clist = NULL;
62         FILE *ifh;
63         const char *fname = "/etc/mactab";
64         char *line;
65         int ctl_sk;
66         int if_index = 1;
67         mactable_t *ch;
68
69         if (1 & getopt32(argv, "sc:", &fname)) {
70                 openlog(applet_name, 0, LOG_LOCAL0);
71                 logmode = LOGMODE_SYSLOG;
72         }
73
74         if ((argc - optind) & 1)
75                 bb_show_usage();
76
77         if (optind < argc) {
78                 char **a = argv + optind;
79
80                 while (*a) {
81                         if (strlen(*a) > IF_NAMESIZE)
82                                 bb_error_msg_and_die("interface name '%s' "
83                                             "too long", *a);
84                         ch = xzalloc(sizeof(mactable_t));
85                         ch->ifname = xstrdup(*a++);
86                         ch->mac = cc_macaddr(*a++);
87                         if (clist)
88                                 clist->prev = ch;
89                         ch->next = clist;
90                         clist = ch;
91                 }
92         } else {
93                 ifh = xfopen(fname, "r");
94
95                 while ((line = xmalloc_fgets(ifh)) != NULL) {
96                         char *line_ptr;
97                         size_t name_length;
98
99                         line_ptr = line + strspn(line, " \t");
100                         if ((line_ptr[0] == '#') || (line_ptr[0] == '\n')) {
101                                 free(line);
102                                 continue;
103                         }
104                         name_length = strcspn(line_ptr, " \t");
105                         ch = xzalloc(sizeof(mactable_t));
106                         ch->ifname = xstrndup(line_ptr, name_length);
107                         if (name_length > IF_NAMESIZE)
108                                 bb_error_msg_and_die("interface name '%s' "
109                                                 "too long", ch->ifname);
110                         line_ptr += name_length;
111                         line_ptr += strspn(line_ptr, " \t");
112                         name_length = strspn(line_ptr, "0123456789ABCDEFabcdef:");
113                         line_ptr[name_length] = '\0';
114                         ch->mac = cc_macaddr(line_ptr);
115                         if (clist)
116                                 clist->prev = ch;
117                         ch->next = clist;
118                         clist = ch;
119                         free(line);
120                 }
121                 fclose(ifh);
122         }
123
124         ctl_sk = xsocket(PF_INET, SOCK_DGRAM, 0);
125
126         while (clist) {
127                 struct ifreq ifr;
128
129                 memset(&ifr, 0, sizeof(struct ifreq));
130                 if_index++;
131                 ifr.ifr_ifindex = if_index;
132
133                 /* Get ifname by index or die */
134                 if (ioctl(ctl_sk, SIOCGIFNAME, &ifr))
135                         break;
136
137                 /* Has this device hwaddr? */
138                 if (ioctl(ctl_sk, SIOCGIFHWADDR, &ifr))
139                         continue;
140
141                 /* Search for mac like in ifr.ifr_hwaddr.sa_data */
142                 for (ch = clist; ch; ch = ch->next)
143                         if (!memcmp(ch->mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN))
144                                 break;
145
146                 /* Nothing found for current ifr.ifr_hwaddr.sa_data */
147                 if (ch == NULL)
148                         continue;
149
150                 strcpy(ifr.ifr_newname, ch->ifname);
151                 ioctl_or_perror_and_die(ctl_sk, SIOCSIFNAME, &ifr,
152                                         "cannot change ifname %s to %s",
153                                         ifr.ifr_name, ch->ifname);
154
155                 /* Remove list entry of renamed interface */
156                 if (ch->prev != NULL) {
157                         (ch->prev)->next = ch->next;
158                 } else {
159                         clist = ch->next;
160                 }
161                 if (ch->next != NULL)
162                         (ch->next)->prev = ch->prev;
163                 if (ENABLE_FEATURE_CLEAN_UP) {
164                         free(ch->ifname);
165                         free(ch->mac);
166                         free(ch);
167                 }
168         }
169
170         return 0;
171 }