New applet, nameif by Nick Fedchik and myself.
diff --git a/networking/nameif.c b/networking/nameif.c
new file mode 100644
index 0000000..1edd641
--- /dev/null
+++ b/networking/nameif.c
@@ -0,0 +1,217 @@
+/* 
+ * nameif.c - Naming Interfaces based on MAC address for busybox.
+ *
+ * Writen 2000 by Andi Kleen.
+ * Busybox port 2002 by Nick Fedchik <nick@fedchik.org.ua>
+ *			Glenn McGrath <bug1@optushome.com.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"
+
+/* set interface name, from <linux/sockios.h> */
+#define SIOCSIFNAME	0x8923
+/* 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 **pprev;
+	char *ifname;
+	struct ether_addr *mac;
+} mactable_t;
+
+static void serror_msg_and_die(const char use_syslog, const char *s, ...)
+{
+	va_list ap;
+
+	va_start(ap, s);
+
+	if (use_syslog) {
+		openlog("nameif", 0, LOG_LOCAL0);
+		syslog(LOG_ERR, s, ap);
+		closelog();
+	} else {
+		vfprintf(stderr, s, ap);
+		putc('\n', stderr);
+	}
+
+	va_end(ap);
+
+	exit(EXIT_FAILURE);
+}
+
+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;
+
+	static struct option opts[] = {
+		{"syslog", 0, NULL, 's'},
+		{"configfile", 1, NULL, 'c'},
+		{NULL},
+	};
+
+	while ((opt = getopt_long(argc, argv, "c:s", opts, NULL)) != -1) {
+		switch (opt) {
+		case 'c':
+			fname = optarg;
+			break;
+		case 's':
+			use_syslog = 1;
+			break;
+		default:
+			show_usage();
+		}
+	}
+
+	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]);
+			}
+			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->ifname = strdup(argv[optind - 1]);
+			ch->mac = xcalloc(1, ETH_ALEN);
+			memcpy(ch->mac, &mac, ETH_ALEN);
+			optind++;
+			if (clist)
+				clist->pprev = &ch->next;
+			ch->next = clist;
+			ch->pprev = &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;
+
+			line_ptr = line + strspn(line, " \t");
+			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]); 
+			}
+			ch = xcalloc(1, sizeof(mactable_t));
+			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);
+			if (clist)
+				clist->pprev = &ch->next;
+			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;
+
+		linenum++;
+		if (linenum < 3)
+			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_and_die(use_syslog, "cannot change name of %s to %s: %s", ifr.ifr_name, ch->ifname, strerror(errno));
+		}
+		for (ch = clist; ch; ch = ch->next)
+			if (!memcmp(ch->mac, ifr.ifr_hwaddr.sa_data, ETH_ALEN))
+				break;
+		if (ch == NULL) {
+			continue;
+		}
+		strcpy(ifr.ifr_newname, ch->ifname);
+
+		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));
+		}
+		*ch->pprev = ch->next;
+		free(ch);
+		free(line);
+	}
+	fclose(ifh);
+
+	while (clist) {
+		mactable_t *ch;
+
+		ch = clist;
+		clist = clist->next;
+		free(ch);
+	}
+
+	return 0;
+}