////////////////////////////////////////////////////////////////////////////////
// Copyright 2016 Google LLC.
//
// This software is licensed under the terms defined in the Widevine Master
// License Agreement. For a copy of this agreement, please contact
// widevine-licensing@google.com.
////////////////////////////////////////////////////////////////////////////////

// Contains ecb crypto routines for widevine protocols. These routines are used
// as part of licensing and provisioning request handling.

#ifndef COMMON_ECB_UTIL_H_
#define COMMON_ECB_UTIL_H_

#include <string>

#include "absl/strings/string_view.h"

namespace widevine {
namespace crypto_util {

// Encrypts |src| into |dst| using 3DES ECB2 mode with the given key. This is
// used for protecting content keys on some older Widevine keyboxes, and is not
// intended for any other purpose. Returns false and sets *|dst|="" if
// unsuccessful. Key should be 16 bytes. The first 8 are key2 of the 3DES key
// bundle, and the last 8 bytes are key1 and key3. |src| must be a multiple of
// 8 bytes.
bool Encrypt3DesEcb(absl::string_view key, absl::string_view src, std::string* dst);

// Decrypts |src| into |dst| using 3DES ECB2 mode with the given (16-byte)
// key. This is used for protecting content keys on some older Widevine
// keyboxes, and is not intended for any other purpose.
// Returns false and sets *|dst|="" if unsuccessful. Note that it can only
// fail if invalid key or data sizes are passed in.
// Key should be 16 bytes. The first 8 are key2 of the 3DES key bundle,
// and the last 8 bytes are key1 and key3. |src| must be a multiple of
// 8 bytes.
bool Decrypt3DesEcb(absl::string_view key, absl::string_view src, std::string* dst);

// Encrypts |src| into |dst| using AES ECB mode with the given
// key. This is used for protecting content keys on Widevine devices,
// and is not intended for any other purpose.
// Returns false and sets *|dst|="" if unsuccessful. Note that it can only
// fail if invalid key or data sizes are passed in.
// Key must be 16 bytes, and src must be a multiple of 16 bytes.
bool EncryptAesEcb(absl::string_view key, absl::string_view src, std::string* dst);

// Decrypts |src| into |dst| using AES ECB mode with the given
// key. This is used for protecting content keys on Widevine devices,
// and is not intended for any other purpose.
// Returns false and sets *|dst|="" if unsuccessful. Note that it can only
// fail if invalid key or data sizes are passed in.
// Key must be 16 bytes, and src must be a multiple of 16 bytes.
bool DecryptAesEcb(absl::string_view key, absl::string_view src, std::string* dst);

}  // namespace crypto_util
}  // namespace widevine

#endif  // COMMON_ECB_UTIL_H_