Get interface names using ioctl rather than /proc, from Nick Fedchik

This commit is contained in:
Glenn L McGrath 2002-12-17 12:43:43 +00:00
parent cf1fee06a5
commit 688cf014af

View File

@ -22,21 +22,20 @@
* *
*/ */
#include <sys/syslog.h> #include <sys/syslog.h>
#include <sys/socket.h> #include <sys/socket.h>
#include <sys/ioctl.h> #include <sys/ioctl.h>
#include <errno.h> #include <errno.h>
#include <getopt.h> #include <getopt.h>
#include <stdlib.h> #include <stdlib.h>
#include <string.h> #include <string.h>
#include <net/if.h> #include <net/if.h>
#include <netinet/ether.h> #include <netinet/ether.h>
#include <linux/sockios.h>
#include "busybox.h" #include "busybox.h"
/* set interface name, from <linux/sockios.h> */
#define SIOCSIFNAME 0x8923
/* Octets in one ethernet addr, from <linux/if_ether.h> */ /* Octets in one ethernet addr, from <linux/if_ether.h> */
#define ETH_ALEN 6 #define ETH_ALEN 6
@ -46,12 +45,12 @@
typedef struct mactable_s { typedef struct mactable_s {
struct mactable_s *next; struct mactable_s *next;
struct mactable_s **pprev; struct mactable_s *prev;
char *ifname; char *ifname;
struct ether_addr *mac; struct ether_addr *mac;
} mactable_t; } 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; va_list ap;
@ -71,16 +70,31 @@ static void serror_msg_and_die(const char use_syslog, const char *s, ...)
exit(EXIT_FAILURE); 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) int nameif_main(int argc, char **argv)
{ {
mactable_t *clist = NULL; mactable_t *clist = NULL;
FILE *ifh; FILE *ifh;
char *fname = "/etc/mactab"; char *fname = "/etc/mactab";
char *line; char *line;
unsigned short linenum = 0;
unsigned char use_syslog = 0; unsigned char use_syslog = 0;
int ctl_sk = -1; int ctl_sk = -1;
int opt; int opt;
int if_index = 1;
mactable_t *ch = NULL;
static struct option opts[] = { static struct option opts[] = {
{"syslog", 0, NULL, 's'}, {"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(); show_usage();
}
if (optind < argc) { if (optind < argc) {
while (optind < argc) { while (optind < argc) {
struct ether_addr *mac;
mactable_t *ch;
if (strlen(argv[optind]) > IF_NAMESIZE) { if (strlen(argv[optind]) > IF_NAMESIZE)
serror_msg_and_die(use_syslog, "interface name `%s' too long", argv[optind]); serror(use_syslog, "interface name `%s' too long",
} argv[optind]);
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 = xcalloc(1, sizeof(mactable_t));
ch->next = NULL;
ch->prev = NULL;
ch->ifname = strdup(argv[optind - 1]); ch->ifname = strdup(argv[optind - 1]);
ch->mac = xcalloc(1, ETH_ALEN); ch->mac = cc_macaddr(argv[optind], use_syslog);
memcpy(ch->mac, mac, ETH_ALEN);
optind++; optind++;
if (clist) if (clist)
clist->pprev = &ch->next; clist->prev = ch->next;
ch->next = clist; ch->next = clist;
ch->pprev = &clist; ch->prev = clist;
clist = ch; clist = ch;
} }
} else { } else {
ifh = xfopen(fname, "r"); ifh = xfopen(fname, "r");
while ((line = get_line_from_file(ifh)) != NULL) { while ((line = get_line_from_file(ifh)) != NULL) {
struct ether_addr *mac;
mactable_t *ch;
char *line_ptr; char *line_ptr;
unsigned short name_length; unsigned short name_length;
@ -142,74 +149,71 @@ int nameif_main(int argc, char **argv)
if ((line_ptr[0] == '#') || (line_ptr[0] == '\n')) if ((line_ptr[0] == '#') || (line_ptr[0] == '\n'))
continue; continue;
name_length = strcspn(line_ptr, " \t"); name_length = strcspn(line_ptr, " \t");
if (name_length > IF_NAMESIZE) { if (name_length > IF_NAMESIZE)
serror_msg_and_die(use_syslog, "interface name `%s' too long", argv[optind]); serror(use_syslog, "interface name `%s' too long",
} argv[optind]);
ch = xcalloc(1, sizeof(mactable_t)); ch = xcalloc(1, sizeof(mactable_t));
ch->next = NULL;
ch->prev = NULL;
ch->ifname = strndup(line_ptr, name_length); ch->ifname = strndup(line_ptr, name_length);
line_ptr += name_length; line_ptr += name_length;
line_ptr += strspn(line_ptr, " \t"); line_ptr += strspn(line_ptr, " \t");
name_length = strspn(line_ptr, "0123456789ABCDEFabcdef:"); name_length = strspn(line_ptr, "0123456789ABCDEFabcdef:");
line_ptr[name_length] = '\0'; line_ptr[name_length] = '\0';
mac = ether_aton(line_ptr); ch->mac = cc_macaddr(line_ptr, use_syslog);
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);
if (clist) if (clist)
clist->pprev = &ch->next; clist->prev = ch;
ch->next = clist; ch->next = clist;
ch->pprev = &clist;
clist = ch; clist = ch;
free(line); free(line);
} }
fclose(ifh); fclose(ifh);
} }
ifh = xfopen("/proc/net/dev", "r"); if ((ctl_sk = socket(PF_INET, SOCK_DGRAM, 0)) == -1)
while ((line = get_line_from_file(ifh)) != NULL) { serror(use_syslog, "socket: %s", strerror(errno));
char *line_ptr;
unsigned short iface_name_length;
struct ifreq ifr;
mactable_t *ch = NULL;
linenum++; while (clist) {
if (linenum < 3) 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; continue;
line_ptr = line + strspn(line, " \t");
if (line_ptr[0] == '\n') /* Search for mac like in ifr.ifr_hwaddr.sa_data */
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;
}
for (ch = clist; ch; ch = ch->next) for (ch = clist; ch; ch = ch->next)
if (!memcmp(ch->mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN)) if (!memcmp(ch->mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN))
break; break;
if (ch == NULL) {
/* Nothing found for current ifr.ifr_hwaddr.sa_data */
if (ch == NULL)
continue; continue;
}
strcpy(ifr.ifr_newname, ch->ifname); 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) {; /* Remove list entry of renamed interface */
serror_msg_and_die(use_syslog, "cannot change name of %s to %s: %s", ifr.ifr_name, ch->ifname, strerror(errno)); 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(ch);
free(line);
} }
fclose(ifh);
while (clist) { while (clist) {
mactable_t *ch;
ch = clist; ch = clist;
clist = clist->next; clist = clist->next;
free(ch); free(ch);