/* Copyright (c) 2014 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.
*
* Common functions between firmware and kernel verified boot.
*/
#ifndef VBOOT_REFERENCE_VB2_COMMON_H_
#define VBOOT_REFERENCE_VB2_COMMON_H_
#include "2api.h"
#include "2common.h"
#include "2return_codes.h"
#include "2sha.h"
#include "2struct.h"
#include "vb2_struct.h"
/*
* Helper functions to get data pointed to by a public key or signature.
*/
const uint8_t *vb2_packed_key_data(const struct vb2_packed_key *key);
uint8_t *vb2_signature_data(struct vb2_signature *sig);
/**
* Verify the data pointed to by a subfield is inside the parent data.
*
* The subfield has a header pointed to by member, and a separate data
* field at an offset relative to the header. That is:
*
* struct parent {
* (possibly other parent fields)
* struct member {
* (member header fields)
* };
* (possibly other parent fields)
* };
* (possibly some other parent data)
* (member data)
* (possibly some other parent data)
*
* @param parent Parent data
* @param parent_size Parent size in bytes
* @param member Subfield header
* @param member_size Size of subfield header in bytes
* @param member_data_offset Offset of member data from start of member
* @param member_data_size Size of member data in bytes
* @return VB2_SUCCESS, or non-zero if error.
*/
int vb2_verify_member_inside(const void *parent, size_t parent_size,
const void *member, size_t member_size,
ptrdiff_t member_data_offset,
size_t member_data_size);
/**
* Verify a signature is fully contained in its parent data
*
* @param parent Parent data
* @param parent_size Parent size in bytes
* @param sig Signature pointer
* @return VB2_SUCCESS, or non-zero if error.
*/
int vb2_verify_signature_inside(const void *parent,
uint32_t parent_size,
const struct vb2_signature *sig);
/**
* Verify a packed key is fully contained in its parent data
*
* @param parent Parent data
* @param parent_size Parent size in bytes
* @param key Packed key pointer
* @return VB2_SUCCESS, or non-zero if error.
*/
int vb2_verify_packed_key_inside(const void *parent,
uint32_t parent_size,
const struct vb2_packed_key *key);
/**
* Unpack a vboot1-format key for use in verification
*
* The elements of the unpacked key will point into the source buffer, so don't
* free the source buffer until you're done with the key.
*
* @param key Destintion for unpacked key
* @param buf Source buffer containing packed key
* @param size Size of buffer in bytes
* @return VB2_SUCCESS, or non-zero error code if error.
*/
int vb2_unpack_key(struct vb2_public_key *key,
const uint8_t *buf,
uint32_t size);
/**
* Verify a signature against an expected hash digest.
*
* @param key Key to use in signature verification
* @param sig Signature to verify (may be destroyed in process)
* @param digest Digest of signed data
* @param wb Work buffer
* @return VB2_SUCCESS, or non-zero if error.
*/
int vb2_verify_digest(const struct vb2_public_key *key,
struct vb2_signature *sig,
const uint8_t *digest,
const struct vb2_workbuf *wb);
/**
* Verify data matches signature.
*
* @param data Data to verify
* @param size Size of data buffer. Note that amount of data to
* actually validate is contained in sig->data_size.
* @param sig Signature of data (destroyed in process)
* @param key Key to use to validate signature
* @param wb Work buffer
* @return VB2_SUCCESS, or non-zero error code if error.
*/
int vb2_verify_data(const uint8_t *data,
uint32_t size,
struct vb2_signature *sig,
const struct vb2_public_key *key,
const struct vb2_workbuf *wb);
/**
* Check the sanity of a key block using a public key.
*
* Header fields are also checked for sanity. Does not verify key index or key
* block flags. Signature inside block is destroyed during check.
*
* @param block Key block to verify
* @param size Size of key block buffer
* @param key Key to use to verify block
* @param wb Work buffer
* @return VB2_SUCCESS, or non-zero error code if error.
*/
int vb2_verify_keyblock(struct vb2_keyblock *block,
uint32_t size,
const struct vb2_public_key *key,
const struct vb2_workbuf *wb);
/**
* Check the sanity of a firmware preamble using a public key.
*
* The signature in the preamble is destroyed during the check.
*
* @param preamble Preamble to verify
* @param size Size of preamble buffer
* @param key Key to use to verify preamble
* @param wb Work buffer
* @return VB2_SUCCESS, or non-zero error code if error.
*/
int vb2_verify_fw_preamble(struct vb2_fw_preamble *preamble,
uint32_t size,
const struct vb2_public_key *key,
const struct vb2_workbuf *wb);
#endif /* VBOOT_REFERENCE_VB2_COMMON_H_ */