udev_device_event.c revision aa8734ffcb8a895fc8d66ff383cbcf8f4b78f562
/*
* Copyright (C) 2004-2008 Kay Sievers <kay.sievers@vrfy.org>
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <stdio.h>
#include <stddef.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <linux/sockios.h>
#include "udev.h"
#include "udev_rules.h"
struct udev_event *udev_event_new(struct udev_device *dev)
{
struct udev_event *event;
event = malloc(sizeof(struct udev_event));
if (event == NULL)
return NULL;
memset(event, 0x00, sizeof(struct udev_event));
event->dev = dev;
event->udev = udev_device_get_udev(dev);
udev_list_init(&event->run_list);
event->mode = 0660;
util_strlcpy(event->owner, "0", sizeof(event->owner));
util_strlcpy(event->group, "0", sizeof(event->group));
dbg(event->udev, "allocated event %p\n", event);
return event;
}
void udev_event_unref(struct udev_event *event)
{
udev_list_cleanup(event->udev, &event->run_list);
dbg(event->udev, "free event %p\n", event);
free(event);
}
static void kernel_log(struct ifreq ifr)
{
int klog;
FILE *f;
klog = open("/dev/kmsg", O_WRONLY);
if (klog < 0)
return;
f = fdopen(klog, "w");
if (f == NULL) {
close(klog);
return;
}
fprintf(f, "<6>udev: renamed network interface %s to %s\n",
ifr.ifr_name, ifr.ifr_newname);
fclose(f);
}
static int rename_netif(struct udev_event *event)
{
struct udev_device *dev = event->dev;
int sk;
struct ifreq ifr;
int err;
info(event->udev, "changing net interface name from '%s' to '%s'\n",
udev_device_get_sysname(dev), event->name);
if (event->test)
return 0;
sk = socket(PF_INET, SOCK_DGRAM, 0);
if (sk < 0) {
err(event->udev, "error opening socket: %m\n");
return -1;
}
memset(&ifr, 0x00, sizeof(struct ifreq));
util_strlcpy(ifr.ifr_name, udev_device_get_sysname(dev), IFNAMSIZ);
util_strlcpy(ifr.ifr_newname, event->name, IFNAMSIZ);
err = ioctl(sk, SIOCSIFNAME, &ifr);
if (err == 0)
kernel_log(ifr);
else {
int loop;
/* see if the destination interface name already exists */
if (errno != EEXIST) {
err(event->udev, "error changing netif name %s to %s: %m\n",
ifr.ifr_name, ifr.ifr_newname);
goto exit;
}
/* free our own name, another process may wait for us */
util_strlcpy(ifr.ifr_newname, udev_device_get_sysname(dev), IFNAMSIZ);
util_strlcat(ifr.ifr_newname, "_rename", IFNAMSIZ);
err = ioctl(sk, SIOCSIFNAME, &ifr);
if (err != 0) {
err(event->udev, "error changing netif name %s to %s: %m\n",
ifr.ifr_name, ifr.ifr_newname);
goto exit;
}
/* wait 30 seconds for our target to become available */
util_strlcpy(ifr.ifr_name, ifr.ifr_newname, IFNAMSIZ);
util_strlcpy(ifr.ifr_newname, udev_device_get_devnode(dev), IFNAMSIZ);
loop = 30 * 20;
while (loop--) {
err = ioctl(sk, SIOCSIFNAME, &ifr);
if (err == 0) {
kernel_log(ifr);
break;
}
if (errno != EEXIST) {
err(event->udev, "error changing net interface name %s to %s: %m\n",
ifr.ifr_name, ifr.ifr_newname);
break;
}
dbg(event->udev, "wait for netif '%s' to become free, loop=%i\n",
udev_device_get_devnode(dev), (30 * 20) - loop);
usleep(1000 * 1000 / 20);
}
}
exit:
close(sk);
return err;
}
int udev_event_run(struct udev_event *event, struct udev_rules *rules)
{
struct udev_device *dev = event->dev;
int err = 0;
if (udev_device_get_devpath_old(dev) != NULL) {
if (udev_device_rename_db(dev, udev_device_get_devpath(dev)) == 0)
info(event->udev, "moved database from '%s' to '%s'\n",
udev_device_get_devpath_old(dev), udev_device_get_devpath(dev));
}
/* add device node */
if (major(udev_device_get_devnum(dev)) != 0 &&
(strcmp(udev_device_get_action(dev), "add") == 0 || strcmp(udev_device_get_action(dev), "change") == 0)) {
char filename[UTIL_PATH_SIZE];
struct udev_device *dev_old;
dbg(event->udev, "device node add '%s'\n", udev_device_get_devpath(dev));
udev_rules_get_name(rules, event);
if (event->ignore_device) {
info(event->udev, "device event will be ignored\n");
goto exit;
}
if (event->name[0] == '\0') {
info(event->udev, "device node creation supressed\n");
goto exit;
}
/* set device node name */
util_strlcpy(filename, udev_get_dev_path(event->udev), sizeof(filename));
util_strlcat(filename, "/", sizeof(filename));
util_strlcat(filename, event->name, sizeof(filename));
udev_device_set_devnode(dev, filename);
/* read current database entry; cleanup, if it is known device */
dev_old = udev_device_new_from_syspath(event->udev, udev_device_get_syspath(dev));
if (dev_old != NULL) {
info(event->udev, "device '%s' already in database, updating\n",
udev_device_get_devpath(dev));
udev_node_update_old_links(dev, dev_old, event->test);
udev_device_unref(dev_old);
}
udev_device_update_db(dev);
err = udev_node_add(dev, event->mode, event->owner, event->group, event->test);
if (err != 0)
goto exit;
goto exit;
}
/* add netif */
if (strcmp(udev_device_get_subsystem(dev), "net") == 0 && strcmp(udev_device_get_action(dev), "add") == 0) {
dbg(event->udev, "netif add '%s'\n", udev_device_get_devpath(dev));
udev_rules_get_name(rules, event);
if (event->ignore_device) {
info(event->udev, "device event will be ignored\n");
goto exit;
}
if (event->name[0] == '\0') {
info(event->udev, "device renaming supressed\n");
goto exit;
}
/* look if we want to change the name of the netif */
if (strcmp(event->name, udev_device_get_sysname(dev)) != 0) {
char syspath[UTIL_PATH_SIZE];
char *pos;
err = rename_netif(event);
if (err != 0)
goto exit;
info(event->udev, "renamed netif to '%s'\n", event->name);
/* remember old name */
udev_device_add_property(dev, "INTERFACE_OLD", udev_device_get_sysname(dev));
/* now change the devpath, because the kernel device name has changed */
util_strlcpy(syspath, udev_device_get_syspath(dev), sizeof(syspath));
pos = strrchr(syspath, '/');
if (pos != NULL) {
pos[1] = '\0';
util_strlcat(syspath, event->name, sizeof(syspath));
udev_device_set_syspath(event->dev, syspath);
udev_device_add_property(dev, "INTERFACE", udev_device_get_sysname(dev));
info(event->udev, "changed devpath to '%s'\n", udev_device_get_devpath(dev));
}
}
goto exit;
}
/* remove device node */
if (major(udev_device_get_devnum(dev)) != 0 && strcmp(udev_device_get_action(dev), "remove") == 0) {
/* import database entry and delete it */
udev_device_read_db(dev);
if (!event->test)
udev_device_delete_db(dev);
if (udev_device_get_devnode(dev) == NULL) {
char devnode[UTIL_PATH_SIZE];
info(event->udev, "'%s' not found in database, using kernel name '%s'\n",
udev_device_get_syspath(dev), udev_device_get_sysname(dev));
util_strlcpy(devnode, udev_get_dev_path(event->udev), sizeof(devnode));
util_strlcat(devnode, "/", sizeof(devnode));
util_strlcat(devnode, udev_device_get_sysname(dev), sizeof(devnode));
udev_device_set_devnode(dev, devnode);
}
udev_rules_get_run(rules, event);
if (event->ignore_device) {
info(event->udev, "device event will be ignored\n");
goto exit;
}
if (udev_device_get_ignore_remove(dev)) {
info(event->udev, "ignore_remove for '%s'\n", udev_device_get_devnode(dev));
goto exit;
}
err = udev_node_remove(dev, event->test);
goto exit;
}
/* default devices */
udev_rules_get_run(rules, event);
if (event->ignore_device)
info(event->udev, "device event will be ignored\n");
exit:
return err;
}