/* * nameif.c - Naming Interfaces based on MAC address for busybox. * * Written 2000 by Andi Kleen. * Busybox port 2002 by Nick Fedchik <nick@fedchik.org.ua> * Glenn McGrath <bug1@iinet.net.au> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA * 02111-1307 USA * */ #include <sys/syslog.h> #include <sys/socket.h> #include <sys/ioctl.h> #include <errno.h> #include <getopt.h> #include <stdlib.h> #include <string.h> #include <net/if.h> #include <netinet/ether.h> #include "busybox.h" /* Older versions of net/if.h do not appear to define IF_NAMESIZE. */ #ifndef IF_NAMESIZE # ifdef IFNAMSIZ # define IF_NAMESIZE IFNAMSIZ # else # define IF_NAMESIZE 16 # endif #endif /* take from linux/sockios.h */ #define SIOCSIFNAME 0x8923 /* set interface name */ /* Octets in one Ethernet addr, from <linux/if_ether.h> */ #define ETH_ALEN 6 #ifndef ifr_newname #define ifr_newname ifr_ifru.ifru_slave #endif typedef struct mactable_s { struct mactable_s *next; struct mactable_s *prev; char *ifname; struct ether_addr *mac; } mactable_t; static unsigned char use_syslog; static void serror(const char *s, ...) __attribute__ ((noreturn)); static void serror(const char *s, ...) { va_list ap; va_start(ap, s); if (use_syslog) { openlog(bb_applet_name, 0, LOG_LOCAL0); vsyslog(LOG_ERR, s, ap); closelog(); } else { bb_verror_msg(s, ap); putc('\n', stderr); } va_end(ap); exit(EXIT_FAILURE); } /* Check ascii str_macaddr, convert and copy to *mac */ static struct ether_addr *cc_macaddr(char *str_macaddr) { struct ether_addr *lmac, *mac; lmac = ether_aton(str_macaddr); if (lmac == NULL) serror("cannot parse MAC %s", str_macaddr); mac = xmalloc(ETH_ALEN); memcpy(mac, lmac, ETH_ALEN); return mac; } int nameif_main(int argc, char **argv) { mactable_t *clist = NULL; FILE *ifh; const char *fname = "/etc/mactab"; char *line; int ctl_sk; int opt; int if_index = 1; mactable_t *ch; while ((opt = getopt(argc, argv, "c:s")) != -1) { switch (opt) { case 'c': fname = optarg; break; case 's': use_syslog = 1; break; default: bb_show_usage(); } } if ((argc - optind) & 1) bb_show_usage(); if (optind < argc) { char **a = argv + optind; while (*a) { if (strlen(*a) > IF_NAMESIZE) serror("interface name `%s' too long", *a); ch = xcalloc(1, sizeof(mactable_t)); ch->ifname = bb_xstrdup(*a++); ch->mac = cc_macaddr(*a++); if (clist) clist->prev = ch; ch->next = clist; clist = ch; } } else { ifh = bb_xfopen(fname, "r"); while ((line = bb_get_line_from_file(ifh)) != NULL) { char *line_ptr; size_t name_length; line_ptr = line + strspn(line, " \t"); if ((line_ptr[0] == '#') || (line_ptr[0] == '\n')) continue; name_length = strcspn(line_ptr, " \t"); ch = xcalloc(1, sizeof(mactable_t)); ch->ifname = bb_xstrndup(line_ptr, name_length); if (name_length > IF_NAMESIZE) serror("interface name `%s' too long", ch->ifname); line_ptr += name_length; line_ptr += strspn(line_ptr, " \t"); name_length = strspn(line_ptr, "0123456789ABCDEFabcdef:"); line_ptr[name_length] = '\0'; ch->mac = cc_macaddr(line_ptr); if (clist) clist->prev = ch; ch->next = clist; clist = ch; free(line); } fclose(ifh); } if ((ctl_sk = socket(PF_INET, SOCK_DGRAM, 0)) == -1) serror("socket: %m"); while (clist) { struct ifreq ifr; bzero(&ifr, sizeof(struct ifreq)); if_index++; ifr.ifr_ifindex = if_index; /* Get ifname by index or die */ if (ioctl(ctl_sk, SIOCGIFNAME, &ifr)) break; /* Has this device hwaddr? */ if (ioctl(ctl_sk, SIOCGIFHWADDR, &ifr)) continue; /* Search for mac like in ifr.ifr_hwaddr.sa_data */ for (ch = clist; ch; ch = ch->next) if (!memcmp(ch->mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN)) break; /* Nothing found for current ifr.ifr_hwaddr.sa_data */ if (ch == NULL) continue; strcpy(ifr.ifr_newname, ch->ifname); if (ioctl(ctl_sk, SIOCSIFNAME, &ifr) < 0) serror("cannot change ifname %s to %s: %m", ifr.ifr_name, ch->ifname); /* Remove list entry of renamed interface */ if (ch->prev != NULL) { (ch->prev)->next = ch->next; } else { clist = ch->next; } if (ch->next != NULL) (ch->next)->prev = ch->prev; #ifdef CONFIG_FEATURE_CLEAN_UP free(ch->ifname); free(ch->mac); free(ch); #endif } return 0; }