blob: e51d5c94a27380b2954705b53c60745d34d8c4cc [file] [log] [blame]
/* Copyright 2017 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef __CROS_EC_ROLLBACK_H
#define __CROS_EC_ROLLBACK_H
#define CROS_EC_ROLLBACK_COOKIE 0x0b112233
#ifndef __ASSEMBLER__
/**
* Get minimum version set by rollback protection blocks.
*
* @return Minimum rollback version, 0 if neither block is initialized,
* negative value on error.
*/
int rollback_get_minimum_version(void);
/**
* Get device secret from rollback protection block.
*
* @param secret CONFIG_ROLLBACK_SECRET_SIZE-long buffer to copy the secret to.
*
* @return EC_SUCCESS on success, EC_ERROR_* on error (e.g. secret is not
* initialized)
*/
int rollback_get_secret(uint8_t *secret);
/**
* Update rollback protection block to the version passed as parameter.
*
* @param next_min_version Minimum version to write in rollback block.
*
* @return EC_SUCCESS on success, EC_ERROR_* on error.
*/
int rollback_update_version(int32_t next_min_version);
/**
* Add entropy to the rollback block.
*
* @param data Data to be added to rollback block secret (after hashing)
* @param len data length
*
* @return EC_SUCCESS on success, EC_ERROR_* on error.
*/
int rollback_add_entropy(uint8_t *data, unsigned int len);
/**
* Lock rollback protection block, reboot if necessary.
*
* @return EC_SUCCESS if rollback was already protected.
*/
int rollback_lock(void);
/**
* Obtain some weak entropy (i.e. not guaranteed to be high quality), based on
* sensors or timing events.
*
* Must be defined if CONFIG_ROLLBACK_SECRET_SIZE is set. May sleep.
*
* @param buffer Buffer to fill with entropy.
* @param len Buffer length.
*
* @return true if the buffer was filled, false on error.
*/
int board_get_entropy(void *buffer, int len);
#endif
#endif /* __CROS_EC_ROLLBACK_H */