glibc/elf/dl-tunable-types.h
Szabolcs Nagy 058308066c elf: Make the tunable struct definition internal only
The representation of the tunables including type information and
the tunable list structure are only used in the implementation not
in the tunables api that is exposed to usage within glibc.

This patch moves the representation related definitions into the
existing dl-tunable-types.h and uses that only for implementation.

The tunable callback and related types are moved to dl-tunables.h
because they are part of the tunables api.

This reduces the details exposed in the tunables api so the internals
are easier to change.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-01-21 14:05:15 +00:00

85 lines
2.6 KiB
C

/* Internal representation of tunables.
Copyright (C) 2016-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#ifndef _TUNABLE_TYPES_H_
#define _TUNABLE_TYPES_H_
/* Note: This header is included in the generated dl-tunables-list.h and
only used internally in the tunables implementation in dl-tunables.c. */
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
typedef enum
{
TUNABLE_TYPE_INT_32,
TUNABLE_TYPE_UINT_64,
TUNABLE_TYPE_SIZE_T,
TUNABLE_TYPE_STRING
} tunable_type_code_t;
typedef struct
{
tunable_type_code_t type_code;
int64_t min;
int64_t max;
} tunable_type_t;
/* Security level for tunables. This decides what to do with individual
tunables for AT_SECURE binaries. */
typedef enum
{
/* Erase the tunable for AT_SECURE binaries so that child processes don't
read it. */
TUNABLE_SECLEVEL_SXID_ERASE = 0,
/* Ignore the tunable for AT_SECURE binaries, but don't erase it, so that
child processes can read it. */
TUNABLE_SECLEVEL_SXID_IGNORE = 1,
/* Read the tunable. */
TUNABLE_SECLEVEL_NONE = 2,
} tunable_seclevel_t;
/* A tunable. */
struct _tunable
{
const char *name; /* Internal name of the tunable. */
tunable_type_t type; /* Data type of the tunable. */
tunable_val_t val; /* The value. */
bool initialized; /* Flag to indicate that the tunable is
initialized. */
tunable_seclevel_t security_level; /* Specify the security level for the
tunable with respect to AT_SECURE
programs. See description of
tunable_seclevel_t to see a
description of the values.
Note that even if the tunable is
read, it may not get used by the
target module if the value is
considered unsafe. */
/* Compatibility elements. */
const char *env_alias; /* The compatibility environment
variable name. */
};
typedef struct _tunable tunable_t;
#endif