monero/src/crypto/chacha.h
2019-03-05 22:05:34 +01:00

97 lines
4.3 KiB
C++

// Copyright (c) 2014-2019, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
#pragma once
#include <stdint.h>
#include <stddef.h>
#define CHACHA_KEY_SIZE 32
#define CHACHA_IV_SIZE 8
#if defined(__cplusplus)
#include <memory.h>
#include "memwipe.h"
#include "mlocker.h"
#include "hash.h"
namespace crypto {
extern "C" {
#endif
void chacha8(const void* data, size_t length, const uint8_t* key, const uint8_t* iv, char* cipher);
void chacha20(const void* data, size_t length, const uint8_t* key, const uint8_t* iv, char* cipher);
#if defined(__cplusplus)
}
using chacha_key = epee::mlocked<tools::scrubbed_arr<uint8_t, CHACHA_KEY_SIZE>>;
#pragma pack(push, 1)
// MS VC 2012 doesn't interpret `class chacha_iv` as POD in spite of [9.0.10], so it is a struct
struct chacha_iv {
uint8_t data[CHACHA_IV_SIZE];
};
#pragma pack(pop)
static_assert(sizeof(chacha_key) == CHACHA_KEY_SIZE && sizeof(chacha_iv) == CHACHA_IV_SIZE, "Invalid structure size");
inline void chacha8(const void* data, std::size_t length, const chacha_key& key, const chacha_iv& iv, char* cipher) {
chacha8(data, length, key.data(), reinterpret_cast<const uint8_t*>(&iv), cipher);
}
inline void chacha20(const void* data, std::size_t length, const chacha_key& key, const chacha_iv& iv, char* cipher) {
chacha20(data, length, key.data(), reinterpret_cast<const uint8_t*>(&iv), cipher);
}
inline void generate_chacha_key(const void *data, size_t size, chacha_key& key, uint64_t kdf_rounds) {
static_assert(sizeof(chacha_key) <= sizeof(hash), "Size of hash must be at least that of chacha_key");
epee::mlocked<tools::scrubbed_arr<char, HASH_SIZE>> pwd_hash;
crypto::cn_slow_hash(data, size, pwd_hash.data(), 0/*variant*/, 0/*prehashed*/, 0/*height*/);
for (uint64_t n = 1; n < kdf_rounds; ++n)
crypto::cn_slow_hash(pwd_hash.data(), pwd_hash.size(), pwd_hash.data(), 0/*variant*/, 0/*prehashed*/, 0/*height*/);
memcpy(&unwrap(unwrap(key)), pwd_hash.data(), sizeof(key));
}
inline void generate_chacha_key_prehashed(const void *data, size_t size, chacha_key& key, uint64_t kdf_rounds) {
static_assert(sizeof(chacha_key) <= sizeof(hash), "Size of hash must be at least that of chacha_key");
epee::mlocked<tools::scrubbed_arr<char, HASH_SIZE>> pwd_hash;
crypto::cn_slow_hash(data, size, pwd_hash.data(), 0/*variant*/, 1/*prehashed*/, 0/*height*/);
for (uint64_t n = 1; n < kdf_rounds; ++n)
crypto::cn_slow_hash(pwd_hash.data(), pwd_hash.size(), pwd_hash.data(), 0/*variant*/, 0/*prehashed*/, 0/*height*/);
memcpy(&unwrap(unwrap(key)), pwd_hash.data(), sizeof(key));
}
inline void generate_chacha_key(std::string password, chacha_key& key, uint64_t kdf_rounds) {
return generate_chacha_key(password.data(), password.size(), key, kdf_rounds);
}
}
#endif