util: rework rm_rf() logic

- Move to its own file rm-rf.c

- Change parameters into a single flags parameter

- Remove "honour sticky" logic, it's unused these days

1 files changed, 2 insertions, 197 deletions

diff --git a/src/shared/util.c b/src/shared/util.c
index 392c42ba2..973f1070b 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -3009,101 +3009,14 @@ int get_ctty(pid_t pid, dev_t *_devnr, char **r) {
         return 0;
 }
 
-int rm_rf_children_dangerous(int fd, bool only_dirs, bool honour_sticky, struct stat *root_dev) {
-        _cleanup_closedir_ DIR *d = NULL;
-        int ret = 0;
-
-        assert(fd >= 0);
-
-        /* This returns the first error we run into, but nevertheless
-         * tries to go on. This closes the passed fd. */
-
-        d = fdopendir(fd);
-        if (!d) {
-                safe_close(fd);
-
-                return errno == ENOENT ? 0 : -errno;
-        }
-
-        for (;;) {
-                struct dirent *de;
-                bool is_dir, keep_around;
-                struct stat st;
-                int r;
-
-                errno = 0;
-                de = readdir(d);
-                if (!de) {
-                        if (errno != 0 && ret == 0)
-                                ret = -errno;
-                        return ret;
-                }
-
-                if (streq(de->d_name, ".") || streq(de->d_name, ".."))
-                        continue;
-
-                if (de->d_type == DT_UNKNOWN ||
-                    honour_sticky ||
-                    (de->d_type == DT_DIR && root_dev)) {
-                        if (fstatat(fd, de->d_name, &st, AT_SYMLINK_NOFOLLOW) < 0) {
-                                if (ret == 0 && errno != ENOENT)
-                                        ret = -errno;
-                                continue;
-                        }
-
-                        is_dir = S_ISDIR(st.st_mode);
-                        keep_around =
-                                honour_sticky &&
-                                (st.st_uid == 0 || st.st_uid == getuid()) &&
-                                (st.st_mode & S_ISVTX);
-                } else {
-                        is_dir = de->d_type == DT_DIR;
-                        keep_around = false;
-                }
-
-                if (is_dir) {
-                        int subdir_fd;
-
-                        /* if root_dev is set, remove subdirectories only, if device is same as dir */
-                        if (root_dev && st.st_dev != root_dev->st_dev)
-                                continue;
-
-                        subdir_fd = openat(fd, de->d_name,
-                                           O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME);
-                        if (subdir_fd < 0) {
-                                if (ret == 0 && errno != ENOENT)
-                                        ret = -errno;
-                                continue;
-                        }
-
-                        r = rm_rf_children_dangerous(subdir_fd, only_dirs, honour_sticky, root_dev);
-                        if (r < 0 && ret == 0)
-                                ret = r;
-
-                        if (!keep_around)
-                                if (unlinkat(fd, de->d_name, AT_REMOVEDIR) < 0) {
-                                        if (ret == 0 && errno != ENOENT)
-                                                ret = -errno;
-                                }
-
-                } else if (!only_dirs && !keep_around) {
-
-                        if (unlinkat(fd, de->d_name, 0) < 0) {
-                                if (ret == 0 && errno != ENOENT)
-                                        ret = -errno;
-                        }
-                }
-        }
-}
-
-_pure_ static int is_temporary_fs(struct statfs *s) {
+bool is_temporary_fs(const struct statfs *s) {
         assert(s);
 
         return F_TYPE_EQUAL(s->f_type, TMPFS_MAGIC) ||
                F_TYPE_EQUAL(s->f_type, RAMFS_MAGIC);
 }
 
-int is_fd_on_temporary_fs(int fd) {
+int fd_is_temporary_fs(int fd) {
         struct statfs s;
 
         if (fstatfs(fd, &s) < 0)
@@ -3112,114 +3025,6 @@ int is_fd_on_temporary_fs(int fd) {
         return is_temporary_fs(&s);
 }
 
-int rm_rf_children(int fd, bool only_dirs, bool honour_sticky, struct stat *root_dev) {
-        struct statfs s;
-
-        assert(fd >= 0);
-
-        if (fstatfs(fd, &s) < 0) {
-                safe_close(fd);
-                return -errno;
-        }
-
-        /* We refuse to clean disk file systems with this call. This
-         * is extra paranoia just to be sure we never ever remove
-         * non-state data */
-        if (!is_temporary_fs(&s)) {
-                log_error("Attempted to remove disk file system, and we can't allow that.");
-                safe_close(fd);
-                return -EPERM;
-        }
-
-        return rm_rf_children_dangerous(fd, only_dirs, honour_sticky, root_dev);
-}
-
-static int file_is_priv_sticky(const char *p) {
-        struct stat st;
-
-        assert(p);
-
-        if (lstat(p, &st) < 0)
-                return -errno;
-
-        return
-                (st.st_uid == 0 || st.st_uid == getuid()) &&
-                (st.st_mode & S_ISVTX);
-}
-
-static int rm_rf_internal(const char *path, bool only_dirs, bool delete_root, bool honour_sticky, bool dangerous) {
-        int fd, r;
-        struct statfs s;
-
-        assert(path);
-
-        /* We refuse to clean the root file system with this
-         * call. This is extra paranoia to never cause a really
-         * seriously broken system. */
-        if (path_equal(path, "/")) {
-                log_error("Attempted to remove entire root file system, and we can't allow that.");
-                return -EPERM;
-        }
-
-        fd = open(path, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME);
-        if (fd < 0) {
-
-                if (errno != ENOTDIR && errno != ELOOP)
-                        return -errno;
-
-                if (!dangerous) {
-                        if (statfs(path, &s) < 0)
-                                return -errno;
-
-                        if (!is_temporary_fs(&s)) {
-                                log_error("Attempted to remove disk file system, and we can't allow that.");
-                                return -EPERM;
-                        }
-                }
-
-                if (delete_root && !only_dirs)
-                        if (unlink(path) < 0 && errno != ENOENT)
-                                return -errno;
-
-                return 0;
-        }
-
-        if (!dangerous) {
-                if (fstatfs(fd, &s) < 0) {
-                        safe_close(fd);
-                        return -errno;
-                }
-
-                if (!is_temporary_fs(&s)) {
-                        log_error("Attempted to remove disk file system, and we can't allow that.");
-                        safe_close(fd);
-                        return -EPERM;
-                }
-        }
-
-        r = rm_rf_children_dangerous(fd, only_dirs, honour_sticky, NULL);
-        if (delete_root) {
-
-                if (honour_sticky && file_is_priv_sticky(path) > 0)
-                        return r;
-
-                if (rmdir(path) < 0 && errno != ENOENT) {
-                        if (r == 0)
-                                r = -errno;
-                }
-        }
-
-        return r;
-}
-
-int rm_rf(const char *path, bool only_dirs, bool delete_root, bool honour_sticky) {
-        return rm_rf_internal(path, only_dirs, delete_root, honour_sticky, false);
-}
-
-int rm_rf_dangerous(const char *path, bool only_dirs, bool delete_root, bool honour_sticky) {
-        return rm_rf_internal(path, only_dirs, delete_root, honour_sticky, true);
-}
-
 int chmod_and_chown(const char *path, mode_t mode, uid_t uid, gid_t gid) {
         assert(path);