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/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
#include <fcntl.h>
#include <linux/fs.h>
#include <stdbool.h>
#include <stddef.h>
#include "missing_fs.h"
/* The chattr() flags to apply when creating a new file *before* writing to it. In particular, flags such as
* FS_NOCOW_FL don't work if applied a-posteriori. All other flags are fine (or even necessary, think
* FS_IMMUTABLE_FL!) to apply after writing to the files. */
#define CHATTR_EARLY_FL \
(FS_NOATIME_FL | \
FS_COMPR_FL | \
FS_NOCOW_FL | \
FS_NOCOMP_FL | \
FS_PROJINHERIT_FL)
#define CHATTR_ALL_FL \
(FS_NOATIME_FL | \
FS_SYNC_FL | \
FS_DIRSYNC_FL | \
FS_APPEND_FL | \
FS_COMPR_FL | \
FS_NODUMP_FL | \
FS_EXTENT_FL | \
FS_IMMUTABLE_FL | \
FS_JOURNAL_DATA_FL | \
FS_SECRM_FL | \
FS_UNRM_FL | \
FS_NOTAIL_FL | \
FS_TOPDIR_FL | \
FS_NOCOW_FL | \
FS_PROJINHERIT_FL)
typedef enum ChattrApplyFlags {
CHATTR_FALLBACK_BITWISE = 1 << 0,
CHATTR_WARN_UNSUPPORTED_FLAGS = 1 << 1,
} ChattrApplyFlags;
int chattr_full(int dir_fd, const char *path, unsigned value, unsigned mask, unsigned *ret_previous, unsigned *ret_final, ChattrApplyFlags flags);
static inline int chattr_at(int dir_fd, const char *path, unsigned value, unsigned mask, unsigned *previous) {
return chattr_full(dir_fd, path, value, mask, previous, NULL, 0);
}
static inline int chattr_fd(int fd, unsigned value, unsigned mask, unsigned *previous) {
return chattr_full(fd, NULL, value, mask, previous, NULL, 0);
}
static inline int chattr_path(const char *path, unsigned value, unsigned mask, unsigned *previous) {
return chattr_full(AT_FDCWD, path, value, mask, previous, NULL, 0);
}
int read_attr_fd(int fd, unsigned *ret);
int read_attr_path(const char *p, unsigned *ret);
/* Combination of chattr flags, that should be appropriate for secrets stored on disk: Secure Remove +
* Exclusion from Dumping + Synchronous Writing (i.e. not caching in memory) + In-Place Updating (i.e. not
* spurious copies). */
#define CHATTR_SECRET_FLAGS (FS_SECRM_FL|FS_NODUMP_FL|FS_SYNC_FL|FS_NOCOW_FL)
static inline int chattr_secret(int fd, ChattrApplyFlags flags) {
return chattr_full(fd, NULL, CHATTR_SECRET_FLAGS, CHATTR_SECRET_FLAGS, NULL, NULL, flags|CHATTR_FALLBACK_BITWISE);
}
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