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/* 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. */
CHASE_AT_RESOLVE_IN_ROOT = 1 << 8, /* Same as openat2()'s RESOLVE_IN_ROOT flag, symlinks are resolved
* relative to the given directory fd instead of root. */
CHASE_PROHIBIT_SYMLINKS = 1 << 9, /* Refuse all symlinks */
CHASE_PARENT = 1 << 10, /* Chase the parent directory of the given path. Note that the
* full path is still stored in ret_path and only the returned
* file descriptor will point to the parent directory. */
CHASE_MKDIR_0755 = 1 << 11, /* Create any missing parent directories in the given path. */
CHASE_EXTRACT_FILENAME = 1 << 12, /* Only return the last component of the resolved path */
} 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 chase_symlinks_and_access(const char *path, const char *root, ChaseSymlinksFlags chase_flags, int access_mode, char **ret_path);
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);
int chase_symlinks_and_unlink(const char *path, const char *root, ChaseSymlinksFlags chase_flags, int unlink_flags, char **ret_path);
int chase_symlinks_at(int dir_fd, const char *path, ChaseSymlinksFlags flags, char **ret_path, int *ret_fd);
int chase_symlinks_at_and_open(int dir_fd, const char *path, ChaseSymlinksFlags chase_flags, int open_flags, char **ret_path);
int chase_symlinks_at_and_opendir(int dir_fd, const char *path, ChaseSymlinksFlags chase_flags, char **ret_path, DIR **ret_dir);
int chase_symlinks_at_and_stat(int dir_fd, const char *path, ChaseSymlinksFlags chase_flags, char **ret_path, struct stat *ret_stat);
int chase_symlinks_at_and_access(int dir_fd, const char *path, ChaseSymlinksFlags chase_flags, int access_mode, char **ret_path);
int chase_symlinks_at_and_fopen_unlocked(int dir_fd, const char *path, ChaseSymlinksFlags chase_flags, const char *open_flags, char **ret_path, FILE **ret_file);
int chase_symlinks_at_and_unlink(int dir_fd, const char *path, ChaseSymlinksFlags chase_flags, int unlink_flags, char **ret_path);
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