diff options
Diffstat (limited to 'udev_node.c')
| -rw-r--r-- | udev_node.c | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/udev_node.c b/udev_node.c new file mode 100644 index 0000000000..9d6e89cfa1 --- /dev/null +++ b/udev_node.c @@ -0,0 +1,307 @@ +/* + * udev-node.c - device node handling + * + * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com> + * Copyright (C) 2004 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., + * 675 Mass Ave, Cambridge, MA 02139, 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 <sys/stat.h> +#include <sys/types.h> + +#include "udev.h" +#include "udev_rules.h" +#include "udev_selinux.h" + + +int udev_node_mknod(struct udevice *udev, const char *file, dev_t devt, mode_t mode, uid_t uid, gid_t gid) +{ + struct stat stats; + int retval = 0; + + if (major(devt) != 0 && strcmp(udev->dev->subsystem, "block") == 0) + mode |= S_IFBLK; + 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 (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); + selinux_resetfscreatecon(); + if (retval != 0) { + err("mknod(%s, %#o, %u, %u) failed: %s", + file, mode, major(devt), minor(devt), strerror(errno)); + goto exit; + } + +perms: + dbg("chmod(%s, %#o)", file, mode); + if (chmod(file, mode) != 0) { + err("chmod(%s, %#o) failed: %s", file, mode, strerror(errno)); + goto exit; + } + + if (uid != 0 || gid != 0) { + dbg("chown(%s, %u, %u)", file, uid, gid); + if (chown(file, uid, gid) != 0) { + err("chown(%s, %u, %u) failed: %s", + file, uid, gid, strerror(errno)); + goto exit; + } + } + +exit: + return retval; +} + +int udev_node_add(struct udevice *udev) +{ + char filename[PATH_SIZE]; + struct name_entry *name_loop; + 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); + + 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'", + 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) { + range = atoi(attr); + if (range > 1) + udev->partitions = range-1; + } + info("creating device partition nodes '%s[1-%i]'", 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); + } + } + } + + /* 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; +} + +int udev_node_remove(struct udevice *udev) +{ + char filename[PATH_SIZE]; + char partitionname[PATH_SIZE]; + struct name_entry *name_loop; + struct stat stats; + int retval; + int i; + int num; + + 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); + } + + snprintf(filename, sizeof(filename), "%s/%s", udev_root, udev->name); + filename[sizeof(filename)-1] = '\0'; + + if (stat(filename, &stats) != 0) { + dbg("device node '%s' not found", filename); + return -1; + } + if (udev->devt && stats.st_rdev != udev->devt) { + info("device node '%s' points to a different device, skip removal", filename); + return -1; + } + + info("removing device node '%s'", filename); + retval = unlink_secure(filename); + if (retval) + return retval; + + setenv("DEVNAME", filename, 1); + + num = udev->partitions; + if (num > 0) { + info("removing all_partitions '%s[1-%i]'", filename, num); + if (num > 255) { + info("garbage from udev database, skip all_partitions removal"); + 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 (strchr(udev->name, '/')) + delete_path(filename); + + return retval; +} |