diff options
Diffstat (limited to 'src/udev-node.c')
| -rw-r--r-- | src/udev-node.c | 636 |
1 files changed, 318 insertions, 318 deletions
diff --git a/src/udev-node.c b/src/udev-node.c index 31046bd713..8d7db7101b 100644 --- a/src/udev-node.c +++ b/src/udev-node.c @@ -31,355 +31,355 @@ #include "udev.h" -#define TMP_FILE_EXT ".udev-tmp" +#define TMP_FILE_EXT ".udev-tmp" static int node_symlink(struct udev *udev, const char *node, const char *slink) { - struct stat stats; - char target[UTIL_PATH_SIZE]; - char *s; - size_t l; - char slink_tmp[UTIL_PATH_SIZE + sizeof(TMP_FILE_EXT)]; - int i = 0; - int tail = 0; - int err = 0; - - /* use relative link */ - target[0] = '\0'; - while (node[i] && (node[i] == slink[i])) { - if (node[i] == '/') - tail = i+1; - i++; - } - s = target; - l = sizeof(target); - while (slink[i] != '\0') { - if (slink[i] == '/') - l = util_strpcpy(&s, l, "../"); - i++; - } - l = util_strscpy(s, l, &node[tail]); - if (l == 0) { - err = -EINVAL; - goto exit; - } - - /* 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(udev, "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 && stats.st_ino != stats2.st_ino) { - info(udev, "replace device node '%s' with symlink to our node '%s'\n", - slink, node); - } else { - err(udev, "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[UTIL_PATH_SIZE]; - int len; - - dbg(udev, "found existing symlink '%s'\n", slink); - len = readlink(slink, buf, sizeof(buf)); - if (len > 0 && len < (int)sizeof(buf)) { - buf[len] = '\0'; - if (strcmp(target, buf) == 0) { - info(udev, "preserve already existing symlink '%s' to '%s'\n", - slink, target); - udev_selinux_lsetfilecon(udev, slink, S_IFLNK); - utimensat(AT_FDCWD, slink, NULL, AT_SYMLINK_NOFOLLOW); - goto exit; - } - } - } - } else { - info(udev, "creating symlink '%s' to '%s'\n", slink, target); - do { - err = util_create_path_selinux(udev, slink); - if (err != 0 && err != -ENOENT) - break; - udev_selinux_setfscreatecon(udev, slink, S_IFLNK); - err = symlink(target, slink); - if (err != 0) - err = -errno; - udev_selinux_resetfscreatecon(udev); - } while (err == -ENOENT); - if (err == 0) - goto exit; - } - - info(udev, "atomically replace '%s'\n", slink); - util_strscpyl(slink_tmp, sizeof(slink_tmp), slink, TMP_FILE_EXT, NULL); - unlink(slink_tmp); - do { - err = util_create_path_selinux(udev, slink_tmp); - if (err != 0 && err != -ENOENT) - break; - udev_selinux_setfscreatecon(udev, slink_tmp, S_IFLNK); - err = symlink(target, slink_tmp); - if (err != 0) - err = -errno; - udev_selinux_resetfscreatecon(udev); - } while (err == -ENOENT); - if (err != 0) { - err(udev, "symlink '%s' '%s' failed: %m\n", target, slink_tmp); - goto exit; - } - err = rename(slink_tmp, slink); - if (err != 0) { - err(udev, "rename '%s' '%s' failed: %m\n", slink_tmp, slink); - unlink(slink_tmp); - } + struct stat stats; + char target[UTIL_PATH_SIZE]; + char *s; + size_t l; + char slink_tmp[UTIL_PATH_SIZE + sizeof(TMP_FILE_EXT)]; + int i = 0; + int tail = 0; + int err = 0; + + /* use relative link */ + target[0] = '\0'; + while (node[i] && (node[i] == slink[i])) { + if (node[i] == '/') + tail = i+1; + i++; + } + s = target; + l = sizeof(target); + while (slink[i] != '\0') { + if (slink[i] == '/') + l = util_strpcpy(&s, l, "../"); + i++; + } + l = util_strscpy(s, l, &node[tail]); + if (l == 0) { + err = -EINVAL; + goto exit; + } + + /* 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(udev, "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 && stats.st_ino != stats2.st_ino) { + info(udev, "replace device node '%s' with symlink to our node '%s'\n", + slink, node); + } else { + err(udev, "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[UTIL_PATH_SIZE]; + int len; + + dbg(udev, "found existing symlink '%s'\n", slink); + len = readlink(slink, buf, sizeof(buf)); + if (len > 0 && len < (int)sizeof(buf)) { + buf[len] = '\0'; + if (strcmp(target, buf) == 0) { + info(udev, "preserve already existing symlink '%s' to '%s'\n", + slink, target); + udev_selinux_lsetfilecon(udev, slink, S_IFLNK); + utimensat(AT_FDCWD, slink, NULL, AT_SYMLINK_NOFOLLOW); + goto exit; + } + } + } + } else { + info(udev, "creating symlink '%s' to '%s'\n", slink, target); + do { + err = util_create_path_selinux(udev, slink); + if (err != 0 && err != -ENOENT) + break; + udev_selinux_setfscreatecon(udev, slink, S_IFLNK); + err = symlink(target, slink); + if (err != 0) + err = -errno; + udev_selinux_resetfscreatecon(udev); + } while (err == -ENOENT); + if (err == 0) + goto exit; + } + + info(udev, "atomically replace '%s'\n", slink); + util_strscpyl(slink_tmp, sizeof(slink_tmp), slink, TMP_FILE_EXT, NULL); + unlink(slink_tmp); + do { + err = util_create_path_selinux(udev, slink_tmp); + if (err != 0 && err != -ENOENT) + break; + udev_selinux_setfscreatecon(udev, slink_tmp, S_IFLNK); + err = symlink(target, slink_tmp); + if (err != 0) + err = -errno; + udev_selinux_resetfscreatecon(udev); + } while (err == -ENOENT); + if (err != 0) { + err(udev, "symlink '%s' '%s' failed: %m\n", target, slink_tmp); + goto exit; + } + err = rename(slink_tmp, slink); + if (err != 0) { + err(udev, "rename '%s' '%s' failed: %m\n", slink_tmp, slink); + unlink(slink_tmp); + } exit: - return err; + return err; } /* find device node of device with highest priority */ static const char *link_find_prioritized(struct udev_device *dev, bool add, const char *stackdir, char *buf, size_t bufsize) { - struct udev *udev = udev_device_get_udev(dev); - DIR *dir; - int priority = 0; - const char *target = NULL; - - if (add) { - priority = udev_device_get_devlink_priority(dev); - util_strscpy(buf, bufsize, udev_device_get_devnode(dev)); - target = buf; - } - - dir = opendir(stackdir); - if (dir == NULL) - return target; - for (;;) { - struct udev_device *dev_db; - struct dirent *dent; - - dent = readdir(dir); - if (dent == NULL || dent->d_name[0] == '\0') - break; - if (dent->d_name[0] == '.') - continue; - - info(udev, "found '%s' claiming '%s'\n", dent->d_name, stackdir); - - /* did we find ourself? */ - if (strcmp(dent->d_name, udev_device_get_id_filename(dev)) == 0) - continue; - - dev_db = udev_device_new_from_id_filename(udev, dent->d_name); - if (dev_db != NULL) { - const char *devnode; - - devnode = udev_device_get_devnode(dev_db); - if (devnode != NULL) { - dbg(udev, "compare priority of '%s'(%i) > '%s'(%i)\n", target, priority, - udev_device_get_devnode(dev_db), udev_device_get_devlink_priority(dev_db)); - if (target == NULL || udev_device_get_devlink_priority(dev_db) > priority) { - info(udev, "'%s' claims priority %i for '%s'\n", - udev_device_get_syspath(dev_db), udev_device_get_devlink_priority(dev_db), stackdir); - priority = udev_device_get_devlink_priority(dev_db); - util_strscpy(buf, bufsize, devnode); - target = buf; - } - } - udev_device_unref(dev_db); - } - } - closedir(dir); - return target; + struct udev *udev = udev_device_get_udev(dev); + DIR *dir; + int priority = 0; + const char *target = NULL; + + if (add) { + priority = udev_device_get_devlink_priority(dev); + util_strscpy(buf, bufsize, udev_device_get_devnode(dev)); + target = buf; + } + + dir = opendir(stackdir); + if (dir == NULL) + return target; + for (;;) { + struct udev_device *dev_db; + struct dirent *dent; + + dent = readdir(dir); + if (dent == NULL || dent->d_name[0] == '\0') + break; + if (dent->d_name[0] == '.') + continue; + + info(udev, "found '%s' claiming '%s'\n", dent->d_name, stackdir); + + /* did we find ourself? */ + if (strcmp(dent->d_name, udev_device_get_id_filename(dev)) == 0) + continue; + + dev_db = udev_device_new_from_id_filename(udev, dent->d_name); + if (dev_db != NULL) { + const char *devnode; + + devnode = udev_device_get_devnode(dev_db); + if (devnode != NULL) { + dbg(udev, "compare priority of '%s'(%i) > '%s'(%i)\n", target, priority, + udev_device_get_devnode(dev_db), udev_device_get_devlink_priority(dev_db)); + if (target == NULL || udev_device_get_devlink_priority(dev_db) > priority) { + info(udev, "'%s' claims priority %i for '%s'\n", + udev_device_get_syspath(dev_db), udev_device_get_devlink_priority(dev_db), stackdir); + priority = udev_device_get_devlink_priority(dev_db); + util_strscpy(buf, bufsize, devnode); + target = buf; + } + } + udev_device_unref(dev_db); + } + } + closedir(dir); + return target; } /* manage "stack of names" with possibly specified device priorities */ static void link_update(struct udev_device *dev, const char *slink, bool add) { - struct udev *udev = udev_device_get_udev(dev); - char name_enc[UTIL_PATH_SIZE]; - char filename[UTIL_PATH_SIZE * 2]; - char dirname[UTIL_PATH_SIZE]; - const char *target; - char buf[UTIL_PATH_SIZE]; - - dbg(udev, "update symlink '%s' of '%s'\n", slink, udev_device_get_syspath(dev)); - - util_path_encode(&slink[strlen(udev_get_dev_path(udev))+1], name_enc, sizeof(name_enc)); - util_strscpyl(dirname, sizeof(dirname), udev_get_run_path(udev), "/links/", name_enc, NULL); - util_strscpyl(filename, sizeof(filename), dirname, "/", udev_device_get_id_filename(dev), NULL); - - if (!add) { - dbg(udev, "removing index: '%s'\n", filename); - if (unlink(filename) == 0) - rmdir(dirname); - } - - target = link_find_prioritized(dev, add, dirname, buf, sizeof(buf)); - if (target == NULL) { - info(udev, "no reference left, remove '%s'\n", slink); - if (unlink(slink) == 0) - util_delete_path(udev, slink); - } else { - info(udev, "creating link '%s' to '%s'\n", slink, target); - node_symlink(udev, target, slink); - } - - if (add) { - int err; - - dbg(udev, "creating index: '%s'\n", filename); - do { - int fd; - - err = util_create_path(udev, filename); - if (err != 0 && err != -ENOENT) - break; - fd = open(filename, O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444); - if (fd >= 0) - close(fd); - else - err = -errno; - } while (err == -ENOENT); - } + struct udev *udev = udev_device_get_udev(dev); + char name_enc[UTIL_PATH_SIZE]; + char filename[UTIL_PATH_SIZE * 2]; + char dirname[UTIL_PATH_SIZE]; + const char *target; + char buf[UTIL_PATH_SIZE]; + + dbg(udev, "update symlink '%s' of '%s'\n", slink, udev_device_get_syspath(dev)); + + util_path_encode(&slink[strlen(udev_get_dev_path(udev))+1], name_enc, sizeof(name_enc)); + util_strscpyl(dirname, sizeof(dirname), udev_get_run_path(udev), "/links/", name_enc, NULL); + util_strscpyl(filename, sizeof(filename), dirname, "/", udev_device_get_id_filename(dev), NULL); + + if (!add) { + dbg(udev, "removing index: '%s'\n", filename); + if (unlink(filename) == 0) + rmdir(dirname); + } + + target = link_find_prioritized(dev, add, dirname, buf, sizeof(buf)); + if (target == NULL) { + info(udev, "no reference left, remove '%s'\n", slink); + if (unlink(slink) == 0) + util_delete_path(udev, slink); + } else { + info(udev, "creating link '%s' to '%s'\n", slink, target); + node_symlink(udev, target, slink); + } + + if (add) { + int err; + + dbg(udev, "creating index: '%s'\n", filename); + do { + int fd; + + err = util_create_path(udev, filename); + if (err != 0 && err != -ENOENT) + break; + fd = open(filename, O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444); + if (fd >= 0) + close(fd); + else + err = -errno; + } while (err == -ENOENT); + } } void udev_node_update_old_links(struct udev_device *dev, struct udev_device *dev_old) { - struct udev *udev = udev_device_get_udev(dev); - struct udev_list_entry *list_entry; - - /* update possible left-over symlinks */ - udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev_old)) { - const char *name = udev_list_entry_get_name(list_entry); - struct udev_list_entry *list_entry_current; - int found; - - /* check if old link name still belongs to this device */ - found = 0; - udev_list_entry_foreach(list_entry_current, udev_device_get_devlinks_list_entry(dev)) { - const char *name_current = udev_list_entry_get_name(list_entry_current); - - if (strcmp(name, name_current) == 0) { - found = 1; - break; - } - } - if (found) - continue; - - info(udev, "update old name, '%s' no longer belonging to '%s'\n", - name, udev_device_get_devpath(dev)); - link_update(dev, name, 0); - } + struct udev *udev = udev_device_get_udev(dev); + struct udev_list_entry *list_entry; + + /* update possible left-over symlinks */ + udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev_old)) { + const char *name = udev_list_entry_get_name(list_entry); + struct udev_list_entry *list_entry_current; + int found; + + /* check if old link name still belongs to this device */ + found = 0; + udev_list_entry_foreach(list_entry_current, udev_device_get_devlinks_list_entry(dev)) { + const char *name_current = udev_list_entry_get_name(list_entry_current); + + if (strcmp(name, name_current) == 0) { + found = 1; + break; + } + } + if (found) + continue; + + info(udev, "update old name, '%s' no longer belonging to '%s'\n", + name, udev_device_get_devpath(dev)); + link_update(dev, name, 0); + } } static int node_fixup(struct udev_device *dev, mode_t mode, uid_t uid, gid_t gid) { - struct udev *udev = udev_device_get_udev(dev); - const char *devnode = udev_device_get_devnode(dev); - dev_t devnum = udev_device_get_devnum(dev); - struct stat stats; - int err = 0; - - if (strcmp(udev_device_get_subsystem(dev), "block") == 0) - mode |= S_IFBLK; - else - mode |= S_IFCHR; - - if (lstat(devnode, &stats) != 0) { - err = -errno; - info(udev, "can not stat() node '%s' (%m)\n", devnode); - goto out; - } - - if (((stats.st_mode & S_IFMT) != (mode & S_IFMT)) || (stats.st_rdev != devnum)) { - err = -EEXIST; - info(udev, "found node '%s' with non-matching devnum %s, skip handling\n", - udev_device_get_devnode(dev), udev_device_get_id_filename(dev)); - goto out; - } - - if ((stats.st_mode & 0777) != (mode & 0777) || stats.st_uid != uid || stats.st_gid != gid) { - info(udev, "set permissions %s, %#o, uid=%u, gid=%u\n", devnode, mode, uid, gid); - chmod(devnode, mode); - chown(devnode, uid, gid); - } else { - info(udev, "preserve permissions %s, %#o, uid=%u, gid=%u\n", devnode, mode, uid, gid); - } - - /* - * Set initial selinux file context only on add events. - * We set the proper context on bootup (triger) or for newly - * added devices, but we don't change it later, in case - * something else has set a custom context in the meantime. - */ - if (strcmp(udev_device_get_action(dev), "add") == 0) - udev_selinux_lsetfilecon(udev, devnode, mode); - - /* always update timestamp when we re-use the node, like on media change events */ - utimensat(AT_FDCWD, devnode, NULL, 0); + struct udev *udev = udev_device_get_udev(dev); + const char *devnode = udev_device_get_devnode(dev); + dev_t devnum = udev_device_get_devnum(dev); + struct stat stats; + int err = 0; + + if (strcmp(udev_device_get_subsystem(dev), "block") == 0) + mode |= S_IFBLK; + else + mode |= S_IFCHR; + + if (lstat(devnode, &stats) != 0) { + err = -errno; + info(udev, "can not stat() node '%s' (%m)\n", devnode); + goto out; + } + + if (((stats.st_mode & S_IFMT) != (mode & S_IFMT)) || (stats.st_rdev != devnum)) { + err = -EEXIST; + info(udev, "found node '%s' with non-matching devnum %s, skip handling\n", + udev_device_get_devnode(dev), udev_device_get_id_filename(dev)); + goto out; + } + + if ((stats.st_mode & 0777) != (mode & 0777) || stats.st_uid != uid || stats.st_gid != gid) { + info(udev, "set permissions %s, %#o, uid=%u, gid=%u\n", devnode, mode, uid, gid); + chmod(devnode, mode); + chown(devnode, uid, gid); + } else { + info(udev, "preserve permissions %s, %#o, uid=%u, gid=%u\n", devnode, mode, uid, gid); + } + + /* + * Set initial selinux file context only on add events. + * We set the proper context on bootup (triger) or for newly + * added devices, but we don't change it later, in case + * something else has set a custom context in the meantime. + */ + if (strcmp(udev_device_get_action(dev), "add") == 0) + udev_selinux_lsetfilecon(udev, devnode, mode); + + /* always update timestamp when we re-use the node, like on media change events */ + utimensat(AT_FDCWD, devnode, NULL, 0); out: - return err; + return err; } int udev_node_add(struct udev_device *dev, mode_t mode, uid_t uid, gid_t gid) { - struct udev *udev = udev_device_get_udev(dev); - char filename[UTIL_PATH_SIZE]; - struct udev_list_entry *list_entry; - int err = 0; - - info(udev, "handling device node '%s', devnum=%s, mode=%#o, uid=%d, gid=%d\n", - udev_device_get_devnode(dev), udev_device_get_id_filename(dev), mode, uid, gid); - - err = node_fixup(dev, mode, uid, gid); - if (err < 0) - goto exit; - - /* always add /dev/{block,char}/$major:$minor */ - snprintf(filename, sizeof(filename), "%s/%s/%u:%u", - udev_get_dev_path(udev), - strcmp(udev_device_get_subsystem(dev), "block") == 0 ? "block" : "char", - major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev))); - node_symlink(udev, udev_device_get_devnode(dev), filename); - - /* create/update symlinks, add symlinks to name index */ - udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) { - if (udev_list_entry_get_num(list_entry)) - /* simple unmanaged link name */ - node_symlink(udev, udev_device_get_devnode(dev), udev_list_entry_get_name(list_entry)); - else - link_update(dev, udev_list_entry_get_name(list_entry), 1); - } + struct udev *udev = udev_device_get_udev(dev); + char filename[UTIL_PATH_SIZE]; + struct udev_list_entry *list_entry; + int err = 0; + + info(udev, "handling device node '%s', devnum=%s, mode=%#o, uid=%d, gid=%d\n", + udev_device_get_devnode(dev), udev_device_get_id_filename(dev), mode, uid, gid); + + err = node_fixup(dev, mode, uid, gid); + if (err < 0) + goto exit; + + /* always add /dev/{block,char}/$major:$minor */ + snprintf(filename, sizeof(filename), "%s/%s/%u:%u", + udev_get_dev_path(udev), + strcmp(udev_device_get_subsystem(dev), "block") == 0 ? "block" : "char", + major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev))); + node_symlink(udev, udev_device_get_devnode(dev), filename); + + /* create/update symlinks, add symlinks to name index */ + udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) { + if (udev_list_entry_get_num(list_entry)) + /* simple unmanaged link name */ + node_symlink(udev, udev_device_get_devnode(dev), udev_list_entry_get_name(list_entry)); + else + link_update(dev, udev_list_entry_get_name(list_entry), 1); + } exit: - return err; + return err; } int udev_node_remove(struct udev_device *dev) { - struct udev *udev = udev_device_get_udev(dev); - struct udev_list_entry *list_entry; - const char *devnode; - struct stat stats; - struct udev_device *dev_check; - char filename[UTIL_PATH_SIZE]; - int err = 0; - - /* remove/update symlinks, remove symlinks from name index */ - udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) - link_update(dev, udev_list_entry_get_name(list_entry), 0); - - /* remove /dev/{block,char}/$major:$minor */ - snprintf(filename, sizeof(filename), "%s/%s/%u:%u", - udev_get_dev_path(udev), - strcmp(udev_device_get_subsystem(dev), "block") == 0 ? "block" : "char", - major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev))); - unlink(filename); + struct udev *udev = udev_device_get_udev(dev); + struct udev_list_entry *list_entry; + const char *devnode; + struct stat stats; + struct udev_device *dev_check; + char filename[UTIL_PATH_SIZE]; + int err = 0; + + /* remove/update symlinks, remove symlinks from name index */ + udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) + link_update(dev, udev_list_entry_get_name(list_entry), 0); + + /* remove /dev/{block,char}/$major:$minor */ + snprintf(filename, sizeof(filename), "%s/%s/%u:%u", + udev_get_dev_path(udev), + strcmp(udev_device_get_subsystem(dev), "block") == 0 ? "block" : "char", + major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev))); + unlink(filename); out: - return err; + return err; } |