/*
- * udev-node.c - device node handling
- *
* Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
- * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2004-2006 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
*
* 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.,
- * 675 Mass Ave, Cambridge, MA 02139, USA.
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#include <unistd.h>
#include <errno.h>
#include <grp.h>
+#include <dirent.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "udev_rules.h"
#include "udev_selinux.h"
+#define TMP_FILE_EXT ".udev-tmp"
int udev_node_mknod(struct udevice *udev, const char *file, dev_t devt, mode_t mode, uid_t uid, gid_t gid)
{
+ char file_tmp[PATH_SIZE + sizeof(TMP_FILE_EXT)];
struct stat stats;
int retval = 0;
else
mode |= S_IFCHR;
- if (stat(file, &stats) != 0)
- goto create;
-
- /* preserve node with already correct numbers, to prevent changing the inode number */
- if ((stats.st_mode & S_IFMT) == (mode & S_IFMT) && (stats.st_rdev == devt)) {
- info("preserve file '%s', because it has correct dev_t", file);
- selinux_setfilecon(file, udev->dev->kernel_name, stats.st_mode);
- goto perms;
+ if (lstat(file, &stats) == 0) {
+ if ((stats.st_mode & S_IFMT) == (mode & S_IFMT) && (stats.st_rdev == devt)) {
+ info("preserve file '%s', because it has correct dev_t\n", file);
+ selinux_setfilecon(file, udev->dev->kernel, stats.st_mode);
+ goto perms;
+ }
+ } else {
+ selinux_setfscreatecon(file, udev->dev->kernel, mode);
+ retval = mknod(file, mode, devt);
+ selinux_resetfscreatecon();
+ if (retval == 0)
+ goto perms;
}
- if (unlink(file) != 0)
- err("unlink(%s) failed: %s", file, strerror(errno));
- else
- dbg("already present file '%s' unlinked", file);
-
-create:
- selinux_setfscreatecon(file, udev->dev->kernel_name, mode);
- retval = mknod(file, mode, devt);
+ info("atomically replace '%s'\n", file);
+ strlcpy(file_tmp, file, sizeof(file_tmp));
+ strlcat(file_tmp, TMP_FILE_EXT, sizeof(file_tmp));
+ unlink(file_tmp);
+ selinux_setfscreatecon(file_tmp, udev->dev->kernel, mode);
+ retval = mknod(file_tmp, mode, devt);
selinux_resetfscreatecon();
if (retval != 0) {
- err("mknod(%s, %#o, %u, %u) failed: %s",
- file, mode, major(devt), minor(devt), strerror(errno));
+ err("mknod(%s, %#o, %u, %u) failed: %s\n",
+ file_tmp, mode, major(devt), minor(devt), strerror(errno));
+ goto exit;
+ }
+ retval = rename(file_tmp, file);
+ if (retval != 0) {
+ err("rename(%s, %s) failed: %s\n",
+ file_tmp, file, strerror(errno));
+ unlink(file_tmp);
goto exit;
}
perms:
- dbg("chmod(%s, %#o)", file, mode);
+ dbg("chmod(%s, %#o)\n", file, mode);
if (chmod(file, mode) != 0) {
- err("chmod(%s, %#o) failed: %s", file, mode, strerror(errno));
+ err("chmod(%s, %#o) failed: %s\n", file, mode, strerror(errno));
goto exit;
}
if (uid != 0 || gid != 0) {
- dbg("chown(%s, %u, %u)", file, uid, gid);
+ dbg("chown(%s, %u, %u)\n", file, uid, gid);
if (chown(file, uid, gid) != 0) {
- err("chown(%s, %u, %u) failed: %s",
+ err("chown(%s, %u, %u) failed: %s\n",
file, uid, gid, strerror(errno));
goto exit;
}
}
+exit:
+ return retval;
+}
+static int node_symlink(const char *node, const char *slink)
+{
+ struct stat stats;
+ char target[PATH_SIZE] = "";
+ char slink_tmp[PATH_SIZE + sizeof(TMP_FILE_EXT)];
+ int i = 0;
+ int tail = 0;
+ int len;
+ int retval = 0;
+
+ /* use relative link */
+ while (node[i] && (node[i] == slink[i])) {
+ if (node[i] == '/')
+ tail = i+1;
+ i++;
+ }
+ while (slink[i] != '\0') {
+ if (slink[i] == '/')
+ strlcat(target, "../", sizeof(target));
+ i++;
+ }
+ strlcat(target, &node[tail], sizeof(target));
+
+ /* preserve link with correct target, do not replace node of other device */
+ if (lstat(slink, &stats) == 0) {
+ if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) {
+ struct stat stats2;
+
+ info("found existing node instead of symlink '%s'\n", slink);
+ if (lstat(node, &stats2) == 0) {
+ if ((stats.st_mode & S_IFMT) == (stats2.st_mode & S_IFMT) &&
+ stats.st_rdev == stats2.st_rdev) {
+ info("replace device node '%s' with symlink to our node '%s'\n", slink, node);
+ } else {
+ err("device node '%s' already exists, link to '%s' will not overwrite it\n", slink, node);
+ goto exit;
+ }
+ }
+ } else if (S_ISLNK(stats.st_mode)) {
+ char buf[PATH_SIZE];
+
+ info("found existing symlink '%s'\n", slink);
+ len = readlink(slink, buf, sizeof(buf));
+ if (len > 0) {
+ buf[len] = '\0';
+ if (strcmp(target, buf) == 0) {
+ info("preserve already existing symlink '%s' to '%s'\n", slink, target);
+ selinux_setfilecon(slink, NULL, S_IFLNK);
+ goto exit;
+ }
+ }
+ }
+ } else {
+ info("creating symlink '%s' to '%s'\n", slink, target);
+ selinux_setfscreatecon(slink, NULL, S_IFLNK);
+ retval = symlink(target, slink);
+ selinux_resetfscreatecon();
+ if (retval == 0)
+ goto exit;
+ }
+
+ info("atomically replace '%s'\n", slink);
+ strlcpy(slink_tmp, slink, sizeof(slink_tmp));
+ strlcat(slink_tmp, TMP_FILE_EXT, sizeof(slink_tmp));
+ unlink(slink_tmp);
+ selinux_setfscreatecon(slink, NULL, S_IFLNK);
+ retval = symlink(target, slink_tmp);
+ selinux_resetfscreatecon();
+ if (retval != 0) {
+ err("symlink(%s, %s) failed: %s\n", target, slink_tmp, strerror(errno));
+ goto exit;
+ }
+ retval = rename(slink_tmp, slink);
+ if (retval != 0) {
+ err("rename(%s, %s) failed: %s\n", slink_tmp, slink, strerror(errno));
+ unlink(slink_tmp);
+ goto exit;
+ }
exit:
return retval;
}
-int udev_node_add(struct udevice *udev, struct udevice *udev_old)
+static int update_link(struct udevice *udev, const char *name)
+{
+ LIST_HEAD(name_list);
+ char slink[PATH_SIZE];
+ char node[PATH_SIZE];
+ struct udevice *udev_db;
+ struct name_entry *device;
+ char target[PATH_MAX] = "";
+ int count;
+ int priority = 0;
+ int rc = 0;
+
+ strlcpy(slink, udev_root, sizeof(slink));
+ strlcat(slink, "/", sizeof(slink));
+ strlcat(slink, name, sizeof(slink));
+
+ count = udev_db_get_devices_by_name(name, &name_list);
+ info("found %i devices with name '%s'\n", count, name);
+
+ /* if we don't have a reference, delete it */
+ if (count <= 0) {
+ info("no reference left, remove '%s'\n", name);
+ if (!udev->test_run) {
+ unlink(slink);
+ delete_path(slink);
+ }
+ goto out;
+ }
+
+ /* find the device with the highest priority */
+ list_for_each_entry(device, &name_list, node) {
+ info("found '%s' for '%s'\n", device->name, name);
+
+ /* did we find ourself? we win, if we have the same priority */
+ if (strcmp(udev->dev->devpath, device->name) == 0) {
+ info("compare (our own) priority of '%s' %i >= %i\n",
+ udev->dev->devpath, udev->link_priority, priority);
+ if (strcmp(udev->name, name) == 0) {
+ info("'%s' is our device node, database inconsistent, skip link update\n", udev->name);
+ } else if (target[0] == '\0' || udev->link_priority >= priority) {
+ priority = udev->link_priority;
+ strlcpy(target, udev->name, sizeof(target));
+ }
+ continue;
+ }
+
+ /* another device, read priority from database */
+ udev_db = udev_device_init(NULL);
+ if (udev_db == NULL)
+ continue;
+ if (udev_db_get_device(udev_db, device->name) == 0) {
+ if (strcmp(udev_db->name, name) == 0) {
+ info("'%s' is a device node of '%s', skip link update\n", udev_db->name, device->name);
+ } else {
+ info("compare priority of '%s' %i > %i\n",
+ udev_db->dev->devpath, udev_db->link_priority, priority);
+ if (target[0] == '\0' || udev_db->link_priority > priority) {
+ priority = udev_db->link_priority;
+ strlcpy(target, udev_db->name, sizeof(target));
+ }
+ }
+ }
+ udev_device_cleanup(udev_db);
+ }
+ name_list_cleanup(&name_list);
+
+ if (target[0] == '\0') {
+ info("no current target for '%s' found\n", name);
+ rc = 1;
+ goto out;
+ }
+
+ /* create symlink to the target with the highest priority */
+ strlcpy(node, udev_root, sizeof(node));
+ strlcat(node, "/", sizeof(node));
+ strlcat(node, target, sizeof(node));
+ info("'%s' with target '%s' has the highest priority %i, create it\n", name, target, priority);
+ if (!udev->test_run) {
+ create_path(slink);
+ node_symlink(node, slink);
+ }
+out:
+ return rc;
+}
+
+void udev_node_update_symlinks(struct udevice *udev, struct udevice *udev_old)
{
- char filename[PATH_SIZE];
struct name_entry *name_loop;
+ char symlinks[PATH_SIZE] = "";
+
+ list_for_each_entry(name_loop, &udev->symlink_list, node) {
+ info("update symlink '%s' of '%s'\n", name_loop->name, udev->dev->devpath);
+ update_link(udev, name_loop->name);
+ strlcat(symlinks, udev_root, sizeof(symlinks));
+ strlcat(symlinks, "/", sizeof(symlinks));
+ strlcat(symlinks, name_loop->name, sizeof(symlinks));
+ strlcat(symlinks, " ", sizeof(symlinks));
+ }
+
+ /* export symlinks to environment */
+ remove_trailing_chars(symlinks, ' ');
+ if (symlinks[0] != '\0')
+ setenv("DEVLINKS", symlinks, 1);
+
+ /* update possible left-over symlinks (device metadata changed) */
+ if (udev_old != NULL) {
+ struct name_entry *link_loop;
+ struct name_entry *link_old_loop;
+ int found;
+
+ /* remove current symlinks from old list */
+ list_for_each_entry(link_old_loop, &udev_old->symlink_list, node) {
+ found = 0;
+ list_for_each_entry(link_loop, &udev->symlink_list, node) {
+ if (strcmp(link_old_loop->name, link_loop->name) == 0) {
+ found = 1;
+ break;
+ }
+ }
+ if (!found) {
+ /* link does no longer belong to this device */
+ info("update old symlink '%s' no longer belonging to '%s'\n",
+ link_old_loop->name, udev->dev->devpath);
+ update_link(udev, link_old_loop->name);
+ }
+ }
+
+ /*
+ * if the node name has changed, delete the node,
+ * or possibly restore a symlink of another device
+ */
+ if (strcmp(udev->name, udev_old->name) != 0)
+ update_link(udev, udev_old->name);
+ }
+}
+
+int udev_node_add(struct udevice *udev)
+{
+ char filename[PATH_SIZE];
uid_t uid;
gid_t gid;
- int tail;
int i;
int retval = 0;
- selinux_init();
-
- snprintf(filename, sizeof(filename), "%s/%s", udev_root, udev->name);
- filename[sizeof(filename)-1] = '\0';
-
- /* create parent directories if needed */
- if (strchr(udev->name, '/'))
- create_path(filename);
+ strlcpy(filename, udev_root, sizeof(filename));
+ strlcat(filename, "/", sizeof(filename));
+ strlcat(filename, udev->name, sizeof(filename));
+ create_path(filename);
if (strcmp(udev->owner, "root") == 0)
uid = 0;
gid = lookup_group(udev->group);
}
- info("creating device node '%s', major = '%d', minor = '%d', " "mode = '%#o', uid = '%d', gid = '%d'",
+ info("creating device node '%s', major=%d, minor=%d, mode=%#o, uid=%d, gid=%d\n",
filename, major(udev->devt), minor(udev->devt), udev->mode, uid, gid);
if (!udev->test_run)
/* take the maximum registered minor range */
attr = sysfs_attr_get_value(udev->dev->devpath, "range");
- if (attr) {
+ if (attr != NULL) {
range = atoi(attr);
if (range > 1)
udev->partitions = range-1;
}
- info("creating device partition nodes '%s[1-%i]'", filename, udev->partitions);
+ info("creating device partition nodes '%s[1-%i]'\n", filename, udev->partitions);
if (!udev->test_run) {
for (i = 1; i <= udev->partitions; i++) {
dev_t part_devt;
}
}
}
-
- /* create symlink(s) if requested */
- if (!list_empty(&udev->symlink_list)) {
- char symlinks[512] = "";
-
- list_for_each_entry(name_loop, &udev->symlink_list, node) {
- char linktarget[PATH_SIZE];
-
- snprintf(filename, sizeof(filename), "%s/%s", udev_root, name_loop->name);
- filename[sizeof(filename)-1] = '\0';
-
- dbg("symlink '%s' to node '%s' requested", filename, udev->name);
- if (!udev->test_run)
- if (strchr(filename, '/'))
- create_path(filename);
-
- /* optimize relative link */
- linktarget[0] = '\0';
- i = 0;
- tail = 0;
- while (udev->name[i] && (udev->name[i] == name_loop->name[i])) {
- if (udev->name[i] == '/')
- tail = i+1;
- i++;
- }
- while (name_loop->name[i] != '\0') {
- if (name_loop->name[i] == '/')
- strlcat(linktarget, "../", sizeof(linktarget));
- i++;
- }
-
- strlcat(linktarget, &udev->name[tail], sizeof(linktarget));
-
- info("creating symlink '%s' to '%s'", filename, linktarget);
- if (!udev->test_run) {
- unlink(filename);
- selinux_setfscreatecon(filename, NULL, S_IFLNK);
- if (symlink(linktarget, filename) != 0)
- err("symlink(%s, %s) failed: %s", linktarget, filename, strerror(errno));
- selinux_resetfscreatecon();
- }
-
- strlcat(symlinks, filename, sizeof(symlinks));
- strlcat(symlinks, " ", sizeof(symlinks));
- }
-
- remove_trailing_chars(symlinks, ' ');
- setenv("DEVLINKS", symlinks, 1);
- }
-
exit:
- selinux_exit();
return retval;
}
-void udev_node_remove_symlinks(struct udevice *udev)
-{
- char filename[PATH_SIZE];
- struct name_entry *name_loop;
- struct stat stats;
-
- if (!list_empty(&udev->symlink_list)) {
- char symlinks[512] = "";
-
- list_for_each_entry(name_loop, &udev->symlink_list, node) {
- snprintf(filename, sizeof(filename), "%s/%s", udev_root, name_loop->name);
- filename[sizeof(filename)-1] = '\0';
-
- if (stat(filename, &stats) != 0) {
- dbg("symlink '%s' not found", filename);
- continue;
- }
- if (udev->devt && stats.st_rdev != udev->devt) {
- info("symlink '%s' points to a different device, skip removal", filename);
- continue;
- }
-
- info("removing symlink '%s'", filename);
- unlink(filename);
-
- if (strchr(filename, '/'))
- delete_path(filename);
-
- strlcat(symlinks, filename, sizeof(symlinks));
- strlcat(symlinks, " ", sizeof(symlinks));
- }
-
- remove_trailing_chars(symlinks, ' ');
- if (symlinks[0] != '\0')
- setenv("DEVLINKS", symlinks, 1);
- }
-}
-
int udev_node_remove(struct udevice *udev)
{
char filename[PATH_SIZE];
char partitionname[PATH_SIZE];
struct stat stats;
- int retval;
+ int retval = 0;
int num;
- udev_node_remove_symlinks(udev);
-
- snprintf(filename, sizeof(filename), "%s/%s", udev_root, udev->name);
- filename[sizeof(filename)-1] = '\0';
-
+ strlcpy(filename, udev_root, sizeof(filename));
+ strlcat(filename, "/", sizeof(filename));
+ strlcat(filename, udev->name, sizeof(filename));
if (stat(filename, &stats) != 0) {
- dbg("device node '%s' not found", filename);
- return -1;
+ info("device node '%s' not found\n", filename);
+ return 0;
}
if (udev->devt && stats.st_rdev != udev->devt) {
- info("device node '%s' points to a different device, skip removal", filename);
+ info("device node '%s' points to a different device, skip removal\n", filename);
return -1;
}
- info("removing device node '%s'", filename);
- retval = unlink_secure(filename);
+ info("removing device node '%s'\n", filename);
+ if (!udev->test_run)
+ retval = unlink_secure(filename);
if (retval)
return retval;
setenv("DEVNAME", filename, 1);
-
num = udev->partitions;
if (num > 0) {
int i;
- info("removing all_partitions '%s[1-%i]'", filename, num);
- if (num > 255) {
- info("garbage from udev database, skip all_partitions removal");
+ info("removing all_partitions '%s[1-%i]'\n", filename, num);
+ if (num > 255)
return -1;
- }
for (i = 1; i <= num; i++) {
snprintf(partitionname, sizeof(partitionname), "%s%d", filename, i);
partitionname[sizeof(partitionname)-1] = '\0';
- unlink_secure(partitionname);
+ if (!udev->test_run)
+ unlink_secure(partitionname);
}
}
-
- if (strchr(udev->name, '/'))
- delete_path(filename);
-
+ delete_path(filename);
return retval;
}
~ianmdlvl / elogind.git / blobdiff