1 files changed, 33 insertions, 0 deletions
diff --git a/src/basic/chase-symlinks.h b/src/basic/chase-symlinks.h
new file mode 100644
index 0000000..a9ee58f
--- /dev/null
+++ b/src/basic/chase-symlinks.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <dirent.h>
+#include <stdio.h>
+
+#include "stat-util.h"
+
+typedef enum ChaseSymlinksFlags {
+        CHASE_PREFIX_ROOT = 1 << 0, /* The specified path will be prefixed by the specified root before beginning the iteration */
+        CHASE_NONEXISTENT = 1 << 1, /* It's OK if the path doesn't actually exist. */
+        CHASE_NO_AUTOFS   = 1 << 2, /* Return -EREMOTE if autofs mount point found */
+        CHASE_SAFE        = 1 << 3, /* Return -EPERM if we ever traverse from unprivileged to privileged files or directories */
+        CHASE_TRAIL_SLASH = 1 << 4, /* Any trailing slash will be preserved */
+        CHASE_STEP        = 1 << 5, /* Just execute a single step of the normalization */
+        CHASE_NOFOLLOW    = 1 << 6, /* Do not follow the path's right-most component. With ret_fd, when the path's
+                                     * right-most component refers to symlink, return O_PATH fd of the symlink. */
+        CHASE_WARN        = 1 << 7, /* Emit an appropriate warning when an error is encountered.
+                                     * Note: this may do an NSS lookup, hence this flag cannot be used in PID 1. */
+} ChaseSymlinksFlags;
+
+bool unsafe_transition(const struct stat *a, const struct stat *b);
+
+/* How many iterations to execute before returning -ELOOP */
+#define CHASE_SYMLINKS_MAX 32
+
+int chase_symlinks(const char *path_with_prefix, const char *root, ChaseSymlinksFlags chase_flags, char **ret_path, int *ret_fd);
+
+int chase_symlinks_and_open(const char *path, const char *root, ChaseSymlinksFlags chase_flags, int open_flags, char **ret_path);
+int chase_symlinks_and_opendir(const char *path, const char *root, ChaseSymlinksFlags chase_flags, char **ret_path, DIR **ret_dir);
+int chase_symlinks_and_stat(const char *path, const char *root, ChaseSymlinksFlags chase_flags, char **ret_path, struct stat *ret_stat, int *ret_fd);
+int chase_symlinks_and_access(const char *path, const char *root, ChaseSymlinksFlags chase_flags, int access_mode, char **ret_path, int *ret_fd);
+int chase_symlinks_and_fopen_unlocked(const char *path, const char *root, ChaseSymlinksFlags chase_flags, const char *open_flags, char **ret_path, FILE **ret_file);