amxmodx/third_party/hashing/hashers/keccak.h

73 lines
1.9 KiB
C++

// //////////////////////////////////////////////////////////
// keccak.h
// Copyright (c) 2014 Stephan Brumme. All rights reserved.
// see http://create.stephan-brumme.com/disclaimer.html
//
#pragma once
#include "../hashing.h"
/// compute Keccak hash (designated SHA3)
/** Usage:
Keccak keccak;
std::string myHash = keccak("Hello World"); // std::string
std::string myHash2 = keccak("How are you", 11); // arbitrary data, 11 bytes
// or in a streaming fashion:
Keccak keccak;
while (more data available)
keccak.add(pointer to fresh data, number of new bytes);
std::string myHash3 = keccak.getHash();
*/
class Keccak //: public Hash
{
public:
/// algorithm variants
enum Bits { Keccak224 = 224, Keccak256 = 256, Keccak384 = 384, Keccak512 = 512 };
/// same as reset()
explicit Keccak(Bits bits = Keccak256);
/// compute hash of a memory block
const char* operator()(const void* data, size_t numBytes);
/// compute hash of a string, excluding final zero
const char* operator()(const char* text, size_t size);
/// add arbitrary number of bytes
void add(const void* data, size_t numBytes);
/// return latest hash as hex characters
const char* getHash();
/// same as reset()
void changeBits(Bits bits);
/// restart
void reset();
private:
/// process a full block
void processBlock(const void* data);
/// process everything left in the internal buffer
void processBuffer();
/// 1600 bits, stored as 25x64 bit, BlockSize is no more than 1152 bits (Keccak224)
enum { StateSize = 1600 / (8 * 8),
MaxBlockSize = 200 - 2 * (224 / 8) };
/// hash
uint64_t m_hash[StateSize];
/// size of processed data in bytes
uint64_t m_numBytes;
/// block size (less or equal to MaxBlockSize)
size_t m_blockSize;
/// valid bytes in m_buffer
size_t m_bufferSize;
/// bytes not processed yet
uint8_t m_buffer[MaxBlockSize];
/// variant
Bits m_bits;
};