76 lines
1.9 KiB
C++
76 lines
1.9 KiB
C++
/* Copyright 2015 OpenMarket Ltd
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
#include <cstddef>
|
|
#include <cstdint>
|
|
|
|
|
|
namespace axolotl {
|
|
|
|
/**
|
|
* The length of the buffer needed to hold a message.
|
|
*/
|
|
std::size_t encode_message_length(
|
|
std::uint32_t counter,
|
|
std::size_t ratchet_key_length,
|
|
std::size_t ciphertext_length,
|
|
std::size_t mac_length
|
|
);
|
|
|
|
|
|
struct MessageWriter {
|
|
std::size_t body_length;
|
|
std::uint8_t * ratchet_key;
|
|
std::uint8_t * ciphertext;
|
|
std::uint8_t * mac;
|
|
};
|
|
|
|
|
|
struct MessageReader {
|
|
std::size_t body_length;
|
|
std::uint8_t version;
|
|
std::uint32_t counter;
|
|
std::size_t ratchet_key_length;
|
|
std::size_t ciphertext_length;
|
|
std::uint8_t const * ratchet_key;
|
|
std::uint8_t const * ciphertext;
|
|
std::uint8_t const * mac;
|
|
};
|
|
|
|
|
|
/**
|
|
* Writes the message headers into the output buffer.
|
|
* Returns a writer struct populated with pointers into the output buffer.
|
|
*/
|
|
MessageWriter encode_message(
|
|
std::uint8_t version,
|
|
std::uint32_t counter,
|
|
std::size_t ratchet_key_length,
|
|
std::size_t ciphertext_length,
|
|
std::uint8_t * output
|
|
);
|
|
|
|
|
|
/**
|
|
* Reads the message headers from the input buffer.
|
|
* Returns a reader struct populated with pointers into the input buffer.
|
|
* On failure the returned body_length will be 0.
|
|
*/
|
|
MessageReader decode_message(
|
|
std::uint8_t const * input, std::size_t input_length,
|
|
std::size_t mac_length
|
|
);
|
|
|
|
|
|
} // namespace axolotl
|