From 688cf014af12c33e2b1dc95834e31db3d3014899 Mon Sep 17 00:00:00 2001 From: Glenn L McGrath Date: Tue, 17 Dec 2002 12:43:43 +0000 Subject: [PATCH] Get interface names using ioctl rather than /proc, from Nick Fedchik --- networking/nameif.c | 132 +++++++++++++++++++++++--------------------- 1 file changed, 68 insertions(+), 64 deletions(-) diff --git a/networking/nameif.c b/networking/nameif.c index 4b2d090ca..a9d422110 100644 --- a/networking/nameif.c +++ b/networking/nameif.c @@ -22,21 +22,20 @@ * */ + #include #include #include - #include #include #include #include #include #include +#include #include "busybox.h" -/* set interface name, from */ -#define SIOCSIFNAME 0x8923 /* Octets in one ethernet addr, from */ #define ETH_ALEN 6 @@ -46,12 +45,12 @@ typedef struct mactable_s { struct mactable_s *next; - struct mactable_s **pprev; + struct mactable_s *prev; char *ifname; struct ether_addr *mac; } mactable_t; -static void serror_msg_and_die(const char use_syslog, const char *s, ...) +static void serror(const char use_syslog, const char *s, ...) { va_list ap; @@ -67,20 +66,35 @@ static void serror_msg_and_die(const char use_syslog, const char *s, ...) } va_end(ap); - + exit(EXIT_FAILURE); } +/* Check ascii str_macaddr, convert and copy to *mac */ +struct ether_addr *cc_macaddr(char *str_macaddr, unsigned char use_syslog) +{ + struct ether_addr *lmac, *mac; + + lmac = ether_aton(str_macaddr); + if (lmac == NULL) + serror(use_syslog, "cannot parse MAC %s", str_macaddr); + mac = xcalloc(1, ETH_ALEN); + memcpy(mac, lmac, ETH_ALEN); + + return mac; +} + int nameif_main(int argc, char **argv) { mactable_t *clist = NULL; FILE *ifh; char *fname = "/etc/mactab"; char *line; - unsigned short linenum = 0; unsigned char use_syslog = 0; int ctl_sk = -1; int opt; + int if_index = 1; + mactable_t *ch = NULL; static struct option opts[] = { {"syslog", 0, NULL, 's'}, @@ -101,40 +115,33 @@ int nameif_main(int argc, char **argv) } } - if ((argc - optind) & 1) { + if ((argc - optind) & 1) show_usage(); - } if (optind < argc) { while (optind < argc) { - struct ether_addr *mac; - mactable_t *ch; - if (strlen(argv[optind]) > IF_NAMESIZE) { - serror_msg_and_die(use_syslog, "interface name `%s' too long", argv[optind]); - } + if (strlen(argv[optind]) > IF_NAMESIZE) + serror(use_syslog, "interface name `%s' too long", + argv[optind]); optind++; - mac = ether_aton(argv[optind]); - if (mac == NULL) { - serror_msg_and_die(use_syslog, "cannot parse MAC %s", argv[optind]); - } + ch = xcalloc(1, sizeof(mactable_t)); + ch->next = NULL; + ch->prev = NULL; ch->ifname = strdup(argv[optind - 1]); - ch->mac = xcalloc(1, ETH_ALEN); - memcpy(ch->mac, mac, ETH_ALEN); + ch->mac = cc_macaddr(argv[optind], use_syslog); optind++; if (clist) - clist->pprev = &ch->next; + clist->prev = ch->next; ch->next = clist; - ch->pprev = &clist; + ch->prev = clist; clist = ch; } } else { ifh = xfopen(fname, "r"); while ((line = get_line_from_file(ifh)) != NULL) { - struct ether_addr *mac; - mactable_t *ch; char *line_ptr; unsigned short name_length; @@ -142,74 +149,71 @@ int nameif_main(int argc, char **argv) if ((line_ptr[0] == '#') || (line_ptr[0] == '\n')) continue; name_length = strcspn(line_ptr, " \t"); - if (name_length > IF_NAMESIZE) { - serror_msg_and_die(use_syslog, "interface name `%s' too long", argv[optind]); - } + if (name_length > IF_NAMESIZE) + serror(use_syslog, "interface name `%s' too long", + argv[optind]); ch = xcalloc(1, sizeof(mactable_t)); + ch->next = NULL; + ch->prev = NULL; ch->ifname = strndup(line_ptr, name_length); line_ptr += name_length; line_ptr += strspn(line_ptr, " \t"); name_length = strspn(line_ptr, "0123456789ABCDEFabcdef:"); line_ptr[name_length] = '\0'; - mac = ether_aton(line_ptr); - if (mac == NULL) { - serror_msg_and_die(use_syslog, "cannot parse MAC %s", argv[optind]); - } - ch->mac = xcalloc(1, ETH_ALEN); - memcpy(ch->mac, mac, ETH_ALEN); + ch->mac = cc_macaddr(line_ptr, use_syslog); if (clist) - clist->pprev = &ch->next; + clist->prev = ch; ch->next = clist; - ch->pprev = &clist; clist = ch; free(line); } fclose(ifh); } - ifh = xfopen("/proc/net/dev", "r"); - while ((line = get_line_from_file(ifh)) != NULL) { - char *line_ptr; - unsigned short iface_name_length; - struct ifreq ifr; - mactable_t *ch = NULL; + if ((ctl_sk = socket(PF_INET, SOCK_DGRAM, 0)) == -1) + serror(use_syslog, "socket: %s", strerror(errno)); - linenum++; - if (linenum < 3) + 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; - line_ptr = line + strspn(line, " \t"); - if (line_ptr[0] == '\n') - continue; - iface_name_length = strcspn(line_ptr, ":"); - if (ctl_sk < 0) - ctl_sk = socket(PF_INET, SOCK_DGRAM, 0); - memset(&ifr, 0, sizeof(struct ifreq)); - strncpy(ifr.ifr_name, line_ptr, iface_name_length); - if (ioctl(ctl_sk, SIOCGIFHWADDR, &ifr) < 0) { -// serror_msg(use_syslog, "cannot read hardware address of %s: %s", ifr.ifr_name, strerror(errno)); - 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; - if (ch == NULL) { + + /* 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(use_syslog, "cannot change ifname %s to %s: %s", + ifr.ifr_name, ch->ifname, strerror(errno)); - if (ioctl(ctl_sk, SIOCSIFNAME, &ifr) < 0) {; - serror_msg_and_die(use_syslog, "cannot change name of %s to %s: %s", ifr.ifr_name, ch->ifname, strerror(errno)); + /* Remove list entry of renamed interface */ + if (ch->prev != NULL) { + (ch->prev)->next = ch->next; + } else { + clist = ch->next; } - *ch->pprev = ch->next; + if (ch->next != NULL) + (ch->next)->prev = ch->prev; free(ch); - free(line); } - fclose(ifh); while (clist) { - mactable_t *ch; - ch = clist; clist = clist->next; free(ch);