// Copyright 2022 Google LLC. All Rights Reserved. This file and proprietary
// source code may only be used and distributed under the Widevine License
// Agreement.
//
//  Reference implementation utilities of OEMCrypto APIs
//
#ifndef WVOEC_UTIL_HMAC_H_
#define WVOEC_UTIL_HMAC_H_

#include <stddef.h>
#include <stdint.h>

#include <string>
#include <vector>

#include "OEMCryptoCENCCommon.h"

namespace wvoec {
namespace util {
// Size of an HMAC-SHA-1 signature.  Same size as a SHA-1 digest.
static constexpr size_t kHmacSha1SignatureSize = 20;
// Size of an HMAC-SHA-256 signature.  Same size as a SHA-256 digest.
static constexpr size_t kHmacSha256SignatureSize = 32;

// == Signature Generate ==

// Generates a HMAC-SHA-1 signature using the provided |key| and
// |message|.  Both |key| and |message| must be non-zero length.
// The input/output |signature_length| should initially contain the
// size of the |signature| buffer, and the function will assign
// the final length of the signature.
//
// Return values:
//    OEMCrypto_SUCCESS if signature is generated successfully;
//        |signature_length| may be updated with the actual
//        signature size
//    OEMCrypto_ERROR_SHORT_BUFFER if the provided |signature| buffer
//        is too small to fit an HMAC-SHA-1 signature;
//        |signature_length| is updated with the require size
//    OEMCrypto_ERROR_INVALID_CONTEXT if any the parameters are
//        incorrect
//    OEMCrypto_ERROR_UNKNOWN_FAILURE otherwise
OEMCryptoResult HmacSha1(const uint8_t* key, size_t key_length,
                         const uint8_t* message, size_t message_length,
                         uint8_t* signature, size_t* signature_length);
OEMCryptoResult HmacSha1(const std::vector<uint8_t>& key,
                         const uint8_t* message, size_t message_length,
                         uint8_t* signature, size_t* signature_length);

std::vector<uint8_t> HmacSha1(const std::vector<uint8_t>& key,
                              const std::vector<uint8_t>& message);

// Generates a HMAC-SHA-256 signature using the provided |key| and
// |message|.  Both |key| and |message| must be non-zero length.
// The input/output |signature_length| should initially contain the
// size of the |signature| buffer, and the function will assign
// the final length of the signature.
//
// Return values:
//    OEMCrypto_SUCCESS if signature is generated successfully;
//        |signature_length| may be updated with the actual
//        signature size
//    OEMCrypto_ERROR_SHORT_BUFFER if the provided |signature| buffer
//        is too small to fit an HMAC-SHA-256 signature;
//        |signature_length| is updated with the require size
//    OEMCrypto_ERROR_INVALID_CONTEXT if any the parameters are
//        incorrect
//    OEMCrypto_ERROR_UNKNOWN_FAILURE otherwise
OEMCryptoResult HmacSha256(const uint8_t* key, size_t key_length,
                           const uint8_t* message, size_t message_length,
                           uint8_t* signature, size_t* signature_length);
OEMCryptoResult HmacSha256(const std::vector<uint8_t>& key,
                           const uint8_t* message, size_t message_length,
                           uint8_t* signature, size_t* signature_length);

bool HmacSha256(const std::vector<uint8_t>& key,
                const std::vector<uint8_t>& message,
                std::vector<uint8_t>* signature);

bool HmacSha256(const std::vector<uint8_t>& key, const std::string& message,
                std::vector<uint8_t>* signature);

std::vector<uint8_t> HmacSha256(const std::vector<uint8_t>& key,
                                const uint8_t* message, size_t message_length);
std::vector<uint8_t> HmacSha256(const std::vector<uint8_t>& key,
                                const std::vector<uint8_t>& message);
std::vector<uint8_t> HmacSha256(const std::vector<uint8_t>& key,
                                const std::string& message);

// == Signature Verification ==

// Verifies an HMAC-SHA-1 signature using the provided |key| and
// |message| against the provided |signature|.
//
// Return values:
//    OEMCrypto_SUCCESS if signature is valid
//    OEMCrypto_ERROR_SIGNATURE_FAILURE if signature is invalid
//    OEMCrypto_ERROR_INVALID_CONTEXT if any the parameters are
//        incorrect
//    OEMCrypto_ERROR_UNKNOWN_FAILURE otherwise
OEMCryptoResult HmacSha1Verify(const uint8_t* key, size_t key_length,
                               const uint8_t* message, size_t message_length,
                               const uint8_t* signature,
                               size_t signature_length);
OEMCryptoResult HmacSha1Verify(const std::vector<uint8_t>& key,
                               const uint8_t* message, size_t message_length,
                               const uint8_t* signature,
                               size_t signature_length);

OEMCryptoResult HmacSha1Verify(const std::vector<uint8_t>& key,
                               const std::vector<uint8_t>& message,
                               const std::vector<uint8_t>& signature);

// Verifies an HMAC-SHA-256 signature using the provided |key| and
// |message| against the provided |signature|.
//
// Return values:
//    OEMCrypto_SUCCESS if signature is valid
//    OEMCrypto_ERROR_SIGNATURE_FAILURE if signature is invalid
//    OEMCrypto_ERROR_INVALID_CONTEXT if any the parameters are
//        incorrect
//    OEMCrypto_ERROR_UNKNOWN_FAILURE otherwise
OEMCryptoResult HmacSha256Verify(const uint8_t* key, size_t key_length,
                                 const uint8_t* message, size_t message_length,
                                 const uint8_t* signature,
                                 size_t signature_length);
OEMCryptoResult HmacSha256Verify(const std::vector<uint8_t>& key,
                                 const uint8_t* message, size_t message_length,
                                 const uint8_t* signature,
                                 size_t signature_length);
OEMCryptoResult HmacSha256Verify(const std::vector<uint8_t>& key,
                                 const std::vector<uint8_t>& message,
                                 const std::vector<uint8_t>& signature);
OEMCryptoResult HmacSha256Verify(const std::vector<uint8_t>& key,
                                 const std::string& message,
                                 const std::vector<uint8_t>& signature);
}  // namespace util
}  // namespace wvoec
#endif  // WVOEC_UTIL_HMAC_H_