git.maemo.org Git - busybox4maemo/blob - 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  * Extended matching support 2008 by Nico Erfurth <masta@perlgolf.de>
   9  *
  10  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
  11  */
  12
  13 #include "libbb.h"
  14 #include <syslog.h>
  15 #include <net/if.h>
  16 #include <netinet/ether.h>
  17 #include <linux/sockios.h>
  18
  19 /* Older versions of net/if.h do not appear to define IF_NAMESIZE. */
  20 #ifndef IF_NAMESIZE
  21 #  ifdef IFNAMSIZ
  22 #    define IF_NAMESIZE IFNAMSIZ
  23 #  else
  24 #    define IF_NAMESIZE 16
  25 #  endif
  26 #endif
  27
  28 /* take from linux/sockios.h */
  29 #define SIOCSIFNAME     0x8923  /* set interface name */
  30
  31 /* Octets in one Ethernet addr, from <linux/if_ether.h> */
  32 #define ETH_ALEN        6
  33
  34 #ifndef ifr_newname
  35 #define ifr_newname ifr_ifru.ifru_slave
  36 #endif
  37
  38 typedef struct ethtable_s {
  39         struct ethtable_s *next;
  40         struct ethtable_s *prev;
  41         char *ifname;
  42         struct ether_addr *mac;
  43 #if ENABLE_FEATURE_NAMEIF_EXTENDED
  44         char *bus_info;
  45         char *driver;
  46 #endif
  47 } ethtable_t;
  48
  49 #if ENABLE_FEATURE_NAMEIF_EXTENDED
  50 /* Cut'n'paste from ethtool.h */
  51 #define ETHTOOL_BUSINFO_LEN 32
  52 /* these strings are set to whatever the driver author decides... */
  53 struct ethtool_drvinfo {
  54         uint32_t cmd;
  55         char  driver[32]; /* driver short name, "tulip", "eepro100" */
  56         char  version[32];  /* driver version string */
  57         char  fw_version[32]; /* firmware version string, if applicable */
  58         char  bus_info[ETHTOOL_BUSINFO_LEN];  /* Bus info for this IF. */
  59         /* For PCI devices, use pci_dev->slot_name. */
  60         char  reserved1[32];
  61         char  reserved2[16];
  62         uint32_t n_stats;  /* number of u64's from ETHTOOL_GSTATS */
  63         uint32_t testinfo_len;
  64         uint32_t eedump_len; /* Size of data from ETHTOOL_GEEPROM (bytes) */
  65         uint32_t regdump_len;  /* Size of data from ETHTOOL_GREGS (bytes) */
  66 };
  67 #define ETHTOOL_GDRVINFO  0x00000003 /* Get driver info. */
  68 #endif
  69
  70
  71 static void nameif_parse_selector(ethtable_t *ch, char *selector)
  72 {
  73         struct ether_addr *lmac;
  74 #if ENABLE_FEATURE_NAMEIF_EXTENDED
  75         int found_selector = 0;
  76
  77         while (*selector) {
  78                 char *next;
  79 #endif
  80                 selector = skip_whitespace(selector);
  81 #if ENABLE_FEATURE_NAMEIF_EXTENDED
  82                 if (*selector == '\0')
  83                         break;
  84                 /* Search for the end .... */
  85                 next = skip_non_whitespace(selector);
  86                 if (*next)
  87                         *next++ = '\0';
  88                 /* Check for selectors, mac= is assumed */
  89                 if (strncmp(selector, "bus=", 4) == 0) {
  90                         ch->bus_info = xstrdup(selector + 4);
  91                         found_selector++;
  92                 } else if (strncmp(selector, "driver=", 7) == 0) {
  93                         ch->driver = xstrdup(selector + 7);
  94                         found_selector++;
  95                 } else {
  96 #endif
  97                         lmac = xmalloc(ETH_ALEN);
  98                         ch->mac = ether_aton_r(selector + (strncmp(selector, "mac=", 4) ? 0 : 4), lmac);
  99                         if (ch->mac == NULL)
 100                                 bb_error_msg_and_die("cannot parse %s", selector);
 101 #if  ENABLE_FEATURE_NAMEIF_EXTENDED
 102                         found_selector++;
 103                 };
 104                 selector = next;
 105         }
 106         if (found_selector == 0)
 107                 bb_error_msg_and_die("no selectors found for %s", ch->ifname);
 108 #endif
 109 }
 110
 111 static void prepend_new_eth_table(ethtable_t **clist, char *ifname, char *selector)
 112 {
 113         ethtable_t *ch;
 114         if (strlen(ifname) >= IF_NAMESIZE)
 115                 bb_error_msg_and_die("interface name '%s' too long", ifname);
 116         ch = xzalloc(sizeof(*ch));
 117         ch->ifname = xstrdup(ifname);
 118         nameif_parse_selector(ch, selector);
 119         ch->next = *clist;
 120         if (*clist)
 121                 (*clist)->prev = ch;
 122         *clist = ch;
 123 }
 124
 125 #if ENABLE_FEATURE_CLEAN_UP
 126 static void delete_eth_table(ethtable_t *ch)
 127 {
 128         free(ch->ifname);
 129 #if ENABLE_FEATURE_NAMEIF_EXTENDED
 130         free(ch->bus_info);
 131         free(ch->driver);
 132 #endif
 133         free(ch->mac);
 134         free(ch);
 135 };
 136 #else
 137 void delete_eth_table(ethtable_t *ch);
 138 #endif
 139
 140 int nameif_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 141 int nameif_main(int argc, char **argv)
 142 {
 143         ethtable_t *clist = NULL;
 144         FILE *ifh;
 145         const char *fname = "/etc/mactab";
 146         char *line;
 147         char *line_ptr;
 148         int linenum;
 149         int ctl_sk;
 150         ethtable_t *ch;
 151
 152         if (1 & getopt32(argv, "sc:", &fname)) {
 153                 openlog(applet_name, 0, LOG_LOCAL0);
 154                 logmode = LOGMODE_SYSLOG;
 155         }
 156         argc -= optind;
 157         argv += optind;
 158
 159         if (argc & 1)
 160                 bb_show_usage();
 161
 162         if (argc) {
 163                 while (*argv) {
 164                         char *ifname = xstrdup(*argv++);
 165                         prepend_new_eth_table(&clist, ifname, *argv++);
 166                 }
 167         } else {
 168                 ifh = xfopen(fname, "r");
 169                 while ((line = xmalloc_fgets(ifh)) != NULL) {
 170                         char *next;
 171
 172                         line_ptr = skip_whitespace(line);
 173                         if ((line_ptr[0] == '#') || (line_ptr[0] == '\n'))
 174                                 goto read_next_line;
 175                         next = skip_non_whitespace(line_ptr);
 176                         if (*next)
 177                                 *next++ = '\0';
 178                         prepend_new_eth_table(&clist, line_ptr, next);
 179                         read_next_line:
 180                         free(line);
 181                 }
 182                 fclose(ifh);
 183         }
 184
 185         ctl_sk = xsocket(PF_INET, SOCK_DGRAM, 0);
 186         ifh = xfopen("/proc/net/dev", "r");
 187
 188         linenum = 0;
 189         while (clist) {
 190                 struct ifreq ifr;
 191 #if  ENABLE_FEATURE_NAMEIF_EXTENDED
 192                 struct ethtool_drvinfo drvinfo;
 193 #endif
 194
 195                 line = xmalloc_fgets(ifh);
 196                 if (line == NULL)
 197                         break; /* Seems like we're done */
 198                 if (linenum++ < 2 )
 199                         goto next_line; /* Skip the first two lines */
 200
 201                 /* Find the current interface name and copy it to ifr.ifr_name */
 202                 line_ptr = skip_whitespace(line);
 203                 *strpbrk(line_ptr, " \t\n:") = '\0';
 204
 205                 memset(&ifr, 0, sizeof(struct ifreq));
 206                 strncpy(ifr.ifr_name, line_ptr, sizeof(ifr.ifr_name));
 207
 208 #if ENABLE_FEATURE_NAMEIF_EXTENDED
 209                 /* Check for driver etc. */
 210                 memset(&drvinfo, 0, sizeof(struct ethtool_drvinfo));
 211                 drvinfo.cmd = ETHTOOL_GDRVINFO;
 212                 ifr.ifr_data = (caddr_t) &drvinfo;
 213                 /* Get driver and businfo first, so we have it in drvinfo */
 214                 ioctl(ctl_sk, SIOCETHTOOL, &ifr);
 215 #endif
 216                 ioctl(ctl_sk, SIOCGIFHWADDR, &ifr);
 217
 218                 /* Search the list for a matching device */
 219                 for (ch = clist; ch; ch = ch->next) {
 220 #if ENABLE_FEATURE_NAMEIF_EXTENDED
 221                         if (ch->bus_info && strcmp(ch->bus_info, drvinfo.bus_info) != 0)
 222                                 continue;
 223                         if (ch->driver && strcmp(ch->driver, drvinfo.driver) != 0)
 224                                 continue;
 225 #endif
 226                         if (ch->mac && memcmp(ch->mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN) != 0)
 227                                 continue;
 228                         /* if we came here, all selectors have matched */
 229                         goto found;
 230                 }
 231                 /* Nothing found for current interface */
 232                 goto next_line;
 233  found:
 234                 if (strcmp(ifr.ifr_name, ch->ifname) != 0) {
 235                         strcpy(ifr.ifr_newname, ch->ifname);
 236                         ioctl_or_perror_and_die(ctl_sk, SIOCSIFNAME, &ifr,
 237                                         "cannot change ifname %s to %s",
 238                                         ifr.ifr_name, ch->ifname);
 239                 }
 240                 /* Remove list entry of renamed interface */
 241                 if (ch->prev != NULL)
 242                         ch->prev->next = ch->next;
 243                 else
 244                         clist = ch->next;
 245                 if (ch->next != NULL)
 246                 ch->next->prev = ch->prev;
 247                 if (ENABLE_FEATURE_CLEAN_UP)
 248                         delete_eth_table(ch);
 249  next_line:
 250                 free(line);
 251         }
 252         if (ENABLE_FEATURE_CLEAN_UP) {
 253                 for (ch = clist; ch; ch = ch->next)
 254                         delete_eth_table(ch);
 255                 fclose(ifh);
 256         };
 257
 258         return 0;
 259 }