summaryrefslogtreecommitdiff
path: root/udev/udev_node.c
diff options
context:
space:
mode:
authorKay Sievers <kay.sievers@vrfy.org>2008-07-30 00:39:15 +0200
committerKay Sievers <kay.sievers@vrfy.org>2008-07-30 00:39:15 +0200
commit726687ad48bdececed1e7e44387c50e009e28208 (patch)
tree0a0084555d2362e87a8942dd630a72d3ef41d9fc /udev/udev_node.c
parentaa5e29a58112aa838be8d04f9e6c994af056f1d1 (diff)
delete all Makefiles and move udev source to udev/
Diffstat (limited to 'udev/udev_node.c')
-rw-r--r--udev/udev_node.c448
1 files changed, 448 insertions, 0 deletions
diff --git a/udev/udev_node.c b/udev/udev_node.c
new file mode 100644
index 0000000000..78b6747043
--- /dev/null
+++ b/udev/udev_node.c
@@ -0,0 +1,448 @@
+/*
+ * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
+ * 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
+ * Free Software Foundation version 2 of the License.
+ *
+ * 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 <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <grp.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "udev.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 preserve = 0;
+ int err = 0;
+
+ if (major(devt) != 0 && strcmp(udev->dev->subsystem, "block") == 0)
+ mode |= S_IFBLK;
+ else
+ mode |= S_IFCHR;
+
+ 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);
+ preserve = 1;
+ selinux_setfilecon(file, udev->dev->kernel, mode);
+ } else {
+ info("atomically replace existing file '%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);
+ err = mknod(file_tmp, mode, devt);
+ selinux_resetfscreatecon();
+ if (err != 0) {
+ err("mknod(%s, %#o, %u, %u) failed: %s\n",
+ file_tmp, mode, major(devt), minor(devt), strerror(errno));
+ goto exit;
+ }
+ err = rename(file_tmp, file);
+ if (err != 0) {
+ err("rename(%s, %s) failed: %s\n",
+ file_tmp, file, strerror(errno));
+ unlink(file_tmp);
+ }
+ }
+ } else {
+ info("mknod(%s, %#o, (%u,%u))\n", file, mode, major(devt), minor(devt));
+ selinux_setfscreatecon(file, udev->dev->kernel, mode);
+ err = mknod(file, mode, devt);
+ selinux_resetfscreatecon();
+ if (err != 0) {
+ err("mknod(%s, %#o, (%u,%u) failed: %s\n",
+ file, mode, major(devt), minor(devt), strerror(errno));
+ goto exit;
+ }
+ }
+
+ if (!preserve || stats.st_mode != mode) {
+ info("chmod(%s, %#o)\n", file, mode);
+ err = chmod(file, mode);
+ if (err != 0) {
+ err("chmod(%s, %#o) failed: %s\n", file, mode, strerror(errno));
+ goto exit;
+ }
+ }
+
+ if (!preserve || stats.st_uid != uid || stats.st_gid != gid) {
+ info("chown(%s, %u, %u)\n", file, uid, gid);
+ err = chown(file, uid, gid);
+ if (err != 0) {
+ err("chown(%s, %u, %u) failed: %s\n", file, uid, gid, strerror(errno));
+ goto exit;
+ }
+ }
+exit:
+ return err;
+}
+
+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;
+}
+
+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)
+{
+ 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 i;
+ int retval = 0;
+
+ 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;
+ else {
+ char *endptr;
+ unsigned long id;
+
+ id = strtoul(udev->owner, &endptr, 10);
+ if (endptr[0] == '\0')
+ uid = (uid_t) id;
+ else
+ uid = lookup_user(udev->owner);
+ }
+
+ if (strcmp(udev->group, "root") == 0)
+ gid = 0;
+ else {
+ char *endptr;
+ unsigned long id;
+
+ id = strtoul(udev->group, &endptr, 10);
+ if (endptr[0] == '\0')
+ gid = (gid_t) id;
+ else
+ gid = lookup_group(udev->group);
+ }
+
+ 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)
+ if (udev_node_mknod(udev, filename, udev->devt, udev->mode, uid, gid) != 0) {
+ retval = -1;
+ goto exit;
+ }
+
+ setenv("DEVNAME", filename, 1);
+
+ /* create all_partitions if requested */
+ if (udev->partitions) {
+ char partitionname[PATH_SIZE];
+ char *attr;
+ int range;
+
+ /* take the maximum registered minor range */
+ attr = sysfs_attr_get_value(udev->dev->devpath, "range");
+ if (attr != NULL) {
+ range = atoi(attr);
+ if (range > 1)
+ udev->partitions = range-1;
+ }
+ 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;
+
+ snprintf(partitionname, sizeof(partitionname), "%s%d", filename, i);
+ partitionname[sizeof(partitionname)-1] = '\0';
+ part_devt = makedev(major(udev->devt), minor(udev->devt) + i);
+ udev_node_mknod(udev, partitionname, part_devt, udev->mode, uid, gid);
+ }
+ }
+ }
+exit:
+ return retval;
+}
+
+int udev_node_remove(struct udevice *udev)
+{
+ char filename[PATH_SIZE];
+ char partitionname[PATH_SIZE];
+ struct stat stats;
+ int retval = 0;
+ int num;
+
+ strlcpy(filename, udev_root, sizeof(filename));
+ strlcat(filename, "/", sizeof(filename));
+ strlcat(filename, udev->name, sizeof(filename));
+ if (stat(filename, &stats) != 0) {
+ 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\n", filename);
+ return -1;
+ }
+
+ 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]'\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';
+ if (!udev->test_run)
+ unlink_secure(partitionname);
+ }
+ }
+ delete_path(filename);
+ return retval;
+}