add a udev helper to do device renames on module load. Essentially,

it's network-functions rename_device ported to C, with locking added.

5 files changed, 380 insertions, 2 deletions

diff --git a/initscripts.spec b/initscripts.spec
index 4a15f207..bab84c2e 100644
--- a/initscripts.spec
+++ b/initscripts.spec
@@ -1,6 +1,6 @@
 Summary: The inittab file and the /etc/init.d scripts.
 Name: initscripts
-Version: 8.31.1
+Version: 8.31.2
 License: GPL
 Group: System Environment/Base
 Release: 1
@@ -189,6 +189,7 @@ rm -rf $RPM_BUILD_ROOT
 /sbin/getkey
 %attr(2755,root,root) /sbin/netreport
 /sbin/initlog
+/sbin/rename_device
 /sbin/service
 /sbin/ppp-watch
 %{_mandir}/man*/*
@@ -208,6 +209,9 @@ rm -rf $RPM_BUILD_ROOT
 %ghost %attr(0664,root,utmp) /var/run/utmp
 
 %changelog
+* Fri Mar 17 2006 Bill Nottingham <notting@redhat.com> 8.31.2-1
+- add udev helper to rename network devices on device creation
+
 * Tue Mar 14 2006 Bill Nottingham <notting@redhat.com> 8.31.1-1
 - fix context of /dev/pts (#185436)
 - translation updates
diff --git a/src/Makefile b/src/Makefile
index c691870b..dacc44bd 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,7 +1,7 @@
 CFLAGS+=$(RPM_OPT_FLAGS) -Wall -D_GNU_SOURCE
 
 PROGS=usernetctl doexec netreport testd usleep ipcalc initlog \
-	getkey ppp-watch consoletype genhostid
+	getkey ppp-watch consoletype genhostid rename_device
 PPPWATCH_OBJS=ppp-watch.o shvar.o
 INITLOG_OBJS=initlog.o process.o
 USLEEP_OBJS=usleep.o
@@ -25,6 +25,7 @@ install:
 	install -m 755 getkey $(ROOT)/sbin/getkey
 	install -m 755 ppp-watch $(ROOT)/sbin/ppp-watch
 	install -m 755 consoletype $(ROOT)/sbin/consoletype
+	install -m 755 rename_device $(ROOT)/sbin/rename_device
 	install -m 644 initlog.1 $(ROOT)$(mandir)/man1
 	install -m 644 genhostid.1 $(ROOT)$(mandir)/man1
 	install -m 644 doexec.1 $(ROOT)$(mandir)/man1
@@ -35,6 +36,7 @@ install:
 	install -m 644 ppp-watch.8 $(ROOT)$(mandir)/man8
 	install -m 644 ipcalc.1 $(ROOT)$(mandir)/man1
 	install -m 644 consoletype.1 $(ROOT)$(mandir)/man1
+	install -m 644 rename_device.1 $(ROOT)$(mandir)/man1
 	install -m 644 initlog.conf $(ROOT)/etc
 
 # this daemon and initscript are useful for testing the up/down/status stuff
@@ -70,5 +72,8 @@ shvar.o: shvar.c
 ppp-watch.o: ppp-watch.c
 	$(CC) $(CFLAGS) `pkg-config glib-2.0 --cflags` -c ppp-watch.c -o ppp-watch.o
 
+rename_device: rename_device.c
+	$(CC) $(CFLAGS) `pkg-config glib-2.0 --cflags` -o $@ $< -Wl,-Bstatic `pkg-config glib-2.0 --libs` -Wl,-Bdynamic
+
 kmodule: kmodule.o
 	$(CC) $(LDFLAGS) -o $@ $< -Wl,-Bstatic -lpopt -Wl,-Bdynamic -lkudzu -lpci
diff --git a/src/rename_device.1 b/src/rename_device.1
new file mode 100644
index 00000000..faaaf5e0
--- /dev/null
+++ b/src/rename_device.1
@@ -0,0 +1,43 @@
+.\" A man page for rename_device(1). -*- nroff -*-
+.\"
+.\" Copyright (C) 2006 Red Hat, Inc. All rights reserved.
+.\"
+.\" This copyrighted material is made available to anyone wishing to use,
+.\" modify, copy, or redistribute it subject to the terms and conditions of the
+.\" GNU General Public License v.2.
+.\"
+.\" 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.,
+.\" 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+.\"
+.\" Author: Bill Nottingham <notting@redhat.com>
+.TH rename_device 1 "Mar 2006"
+
+.SH NAME
+rename_device \- rename ethernet devices
+
+.SH SYNOPSIS
+\fBrename_device\fR
+
+.SH DESCRIPTION
+.B rename_device
+renames ethernet devices, based on configuration in
+\fI/etc/sysconfig/network-scripts\fR. It is meant to be run as a udev
+helper; do not run it directly.
+
+.SH FILES
+
+\fI/etc/sysconfig/network-scripts\fR
+.br
+\fI/etc/udev/rules.d/60-net.rules\fR
+.br
+
+.SH BUGS
+Probably, but let's hope not.  If you find any, please file them in the
+bug database at http://bugzilla.redhat.com/ against the "initscripts"
+component.
diff --git a/src/rename_device.c b/src/rename_device.c
new file mode 100644
index 00000000..9db4d41f
--- /dev/null
+++ b/src/rename_device.c
@@ -0,0 +1,325 @@
+
+/* 
+ * rename_device.c: udev helper to rename ethernet devices.
+ *
+ * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions of the
+ * GNU General Public License v.2.
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/ioctl.h>
+#include <sys/types.h>
+
+#include <linux/sockios.h>
+
+#include <net/if.h>
+
+#include <glib.h>
+
+#define LOCKFILE "/dev/.rename_device.lock"
+
+void sighandler(int dummy) {
+	unlink(LOCKFILE);
+	_exit(1);
+}
+
+struct netdev {
+	char *hwaddr;
+	char *dev;
+	struct netdev *next;
+};
+
+struct netdev *configs = NULL;
+struct netdev *devs = NULL;
+
+struct netdev *get_devs() {
+	DIR *dir;
+	struct dirent *entry;
+	struct netdev *ret = NULL, *tmpdev;
+	
+	dir = opendir("/sys/class/net");
+	if (!dir)
+		return NULL;
+	while ((entry = readdir(dir))) {
+		char *path;
+		gchar *contents;
+		
+		contents = NULL;
+		
+		if (!strcmp(entry->d_name,".") || !strcmp(entry->d_name,"..")) {
+			continue;
+		}
+		if (asprintf(&path,"/sys/class/net/%s/type",entry->d_name) == -1)
+			continue;
+		g_file_get_contents(path, &contents, NULL, NULL);
+		if (!contents) continue;
+		if (atoi(contents) >= 256) {
+			g_free(contents);
+			continue;
+		}
+		g_free(contents);
+		contents = NULL;
+		if (asprintf(&path,"/sys/class/net/%s/address",entry->d_name) == -1)
+			continue;
+		g_file_get_contents(path, &contents, NULL, NULL);
+		if (!contents) continue;
+		contents = g_strstrip(contents);
+		tmpdev = calloc(1, sizeof(struct netdev));
+		tmpdev->dev = g_strstrip(g_strdup(entry->d_name));
+		tmpdev->hwaddr = g_strstrip(g_strdup(contents));
+		if (ret)
+			tmpdev->next = ret;
+		ret = tmpdev;
+		g_free(contents);
+	}
+	return ret;
+}
+
+int isCfg(const struct dirent *dent) {
+	int len = strlen(dent->d_name);
+	
+	if (strncmp(dent->d_name,"ifcfg-",6))
+		return 0;
+	if (strstr(dent->d_name,"rpmnew") ||
+	    strstr(dent->d_name,"rpmsave") ||
+	    strstr(dent->d_name,"rpmorig"))
+		return 0;
+	if (dent->d_name[len-1] == '~')
+		return 0;
+	if (!strncmp(dent->d_name+len-5,".bak",4))
+		return 0;
+	return 1;
+}
+
+struct netdev *get_configs() {
+	int ncfgs = 0;
+	struct netdev *ret, *tmpdev;
+	struct dirent **cfgs;
+	int x;
+	
+	ret = NULL;
+	
+	if ((ncfgs = scandir("/etc/sysconfig/network-scripts",&cfgs,
+			     isCfg, alphasort)) == -1) {
+		return ret;
+	}
+	for (x = 0; x < ncfgs; x++ ) {
+		char *path;
+		char *devname, *hwaddr;
+		gchar *contents, **lines;
+		int i;
+		
+		devname = hwaddr = contents = NULL;
+		lines = NULL;
+		if (asprintf(&path,"/etc/sysconfig/network-scripts/%s",
+			     cfgs[x]->d_name) == -1)
+			continue;
+		g_file_get_contents(path, &contents, NULL, NULL);
+		if (!contents)
+			continue;
+		lines = g_strsplit(contents,"\n", 0);
+		for (i = 0; lines[i]; i++) {
+			if (g_str_has_prefix(lines[i],"DEVICE=")) {
+				devname = lines[i] + 7;
+			}
+			if (g_str_has_prefix(lines[i],"HWADDR=")) {
+				hwaddr = lines[i] + 7;
+			}
+		}
+		if (!devname || !hwaddr) {
+			g_free(contents);
+			g_strfreev(lines);
+			continue;
+		}
+		tmpdev = calloc(1, sizeof(struct netdev));
+		tmpdev->dev = g_strstrip(g_strdup(devname));
+		tmpdev->hwaddr = g_strstrip(g_strdup(hwaddr));
+		if (ret)
+			tmpdev->next = ret;
+		ret = tmpdev;
+		g_free(contents);
+		g_strfreev(lines);
+	}
+	free(cfgs);
+	return ret;
+}
+		
+char *get_hwaddr(char *device) {
+	struct netdev *dev;
+	
+	for (dev = devs; dev; dev = dev->next)
+		if (!strcmp(dev->dev, device))
+			return dev->hwaddr;
+	return NULL;
+}
+		
+char *get_config_by_hwaddr(char *hwaddr) {
+	struct netdev *config;
+	
+	if (!hwaddr) return NULL;
+	
+	for (config = configs; config; config = config->next)
+		if (!strcasecmp(config->hwaddr, hwaddr))
+			return config->dev;
+	return NULL;
+}
+
+char *get_device_by_hwaddr(char *hwaddr) {
+	struct netdev *dev;
+	
+	if (!hwaddr) return NULL;
+	
+	for (dev = devs; dev; dev = dev->next)
+		if (!strcasecmp(dev->hwaddr, hwaddr))
+			return dev->dev;
+	return NULL;
+}
+
+int do_rename(char *src, char *target) {
+	int sock;
+	struct ifreq ifr;
+	int ret;
+	
+	sock = socket(PF_INET, SOCK_DGRAM, 0);
+	if (sock == -1)
+		return 1;
+	
+	memset(&ifr,'\0', sizeof(struct ifreq));
+	g_strlcpy(ifr.ifr_name, src, IFNAMSIZ);
+	g_strlcpy(ifr.ifr_newname, target, IFNAMSIZ);
+	ret = ioctl(sock, SIOCSIFNAME, &ifr);
+	return ret;
+}
+	
+
+void rename_device(char *src, char *target, struct netdev *current) {
+	int rc;
+	
+	if (!current) {
+		current = calloc(1, sizeof(struct netdev));
+		current->dev = src;
+	}
+	
+	rc = do_rename(src, target);
+	if (rc && errno != ENODEV) {
+		char *hw;
+		char *nconfig;
+		char *curdev;
+		char *dev = NULL;
+		struct netdev *i, *tmpdev;
+		
+		hw = get_hwaddr(target);
+		if (!hw)
+			return;
+		
+		nconfig = get_config_by_hwaddr(hw);
+		curdev = get_device_by_hwaddr(hw);
+
+		if (nconfig) {
+			dev = nconfig;
+			for (i = current; i; i = i->next) {
+				if (!strcmp(i->dev,dev))
+					dev = NULL;
+			}
+		}
+		if (!dev)
+			asprintf(&dev,"dev%d",rand());
+		if (!dev)
+			return;
+		tmpdev = calloc(1,sizeof(struct netdev));
+		tmpdev->dev = curdev;
+		if (current)
+			tmpdev->next = current;
+		current = tmpdev;
+		rename_device(curdev, dev, current);
+		do_rename(src,target);
+	}
+}
+
+void take_lock() {
+	int count = 0;
+	int lockfd;
+	
+	while (1) {
+		lockfd = open(LOCKFILE, O_RDWR|O_CREAT|O_EXCL);
+		if (lockfd != -1) {
+			write(lockfd,"%d\n",getpid());
+			close(lockfd);
+			break;
+		}
+		count++;
+		/* If we've slept for 20 seconds, break the lock. */
+		if (count >= 200) {
+			int fd;
+			char buf[32];
+			int pid;
+				
+			fd = open(LOCKFILE, O_RDONLY);
+			if (fd == -1)
+				break;
+			read(fd,buf,32);
+			close(fd);
+			pid = atoi(buf);
+			if (pid && pid != 1) {
+				kill(pid,SIGKILL);
+			}
+		}
+		usleep(100000);
+		continue;
+
+	}
+	return;
+}
+
+int main(int argc, char **argv) {
+	char *src, *target, *hw;
+		
+	take_lock();
+	
+	signal(SIGSEGV,sighandler);
+	signal(SIGKILL,sighandler);
+	signal(SIGTERM,sighandler);
+	signal(SIGSEGV,sighandler);
+	signal(SIGALRM,sighandler);
+	alarm(10);
+	
+	configs = get_configs();
+	devs = get_devs();
+	
+	src = getenv("INTERFACE");
+	if (!src)
+		goto out_unlock;
+	hw = get_hwaddr(src);
+	if (!hw)
+		goto out_unlock;
+	target = get_config_by_hwaddr(hw);
+	if (!target || !strcmp(src,target))
+		goto out_unlock;
+	
+	rename_device(src, target, NULL);
+	printf("INTERFACE=%s\n",target);
+out_unlock:
+	unlink(LOCKFILE);
+	exit(0);
+}
diff --git a/udev/rules.d/60-net.rules b/udev/rules.d/60-net.rules
index ca0b3967..872c7eed 100644
--- a/udev/rules.d/60-net.rules
+++ b/udev/rules.d/60-net.rules
@@ -1 +1,2 @@
+ACTION="add", SUBSYSTEM=="net", IMPORT{program}="/sbin/rename_device"
 SUBSYSTEM=="net", RUN+="/etc/sysconfig/network-scripts/net.hotplug"