Crypto++ 8.9
Free C++ class library of cryptographic schemes
keccak.cpp
1// keccak.cpp - modified by Wei Dai from Ronny Van Keer's public domain
2// sha3-simple.c. All modifications here are placed in the
3// public domain by Wei Dai.
4// Keccack core function moved to keccakc.cpp in AUG 2018
5// by Jeffrey Walton. Separating the core file allows both
6// SHA3 and Keccack to share the core implementation.
7
8/*
9The Keccak sponge function, designed by Guido Bertoni, Joan Daemen,
10Michael Peeters and Gilles Van Assche. For more information, feedback or
11questions, please refer to our website: http://keccak.noekeon.org/
12
13Implementation by Ronny Van Keer, hereby denoted as "the implementer".
14
15To the extent possible under law, the implementer has waived all copyright
16and related or neighboring rights to the source code in this file.
17http://creativecommons.org/publicdomain/zero/1.0/
18*/
19
20#include "pch.h"
21#include "keccak.h"
22
23NAMESPACE_BEGIN(CryptoPP)
24
25// The Keccak core function
26extern void KeccakF1600(word64 *state);
27
28void Keccak::Update(const byte *input, size_t length)
29{
30 CRYPTOPP_ASSERT(!(input == NULLPTR && length != 0));
31 if (length == 0) { return; }
32
33 size_t spaceLeft;
34 while (length >= (spaceLeft = r() - m_counter))
35 {
36 if (spaceLeft)
37 xorbuf(m_state.BytePtr() + m_counter, input, spaceLeft);
38 KeccakF1600(m_state);
39 input += spaceLeft;
40 length -= spaceLeft;
41 m_counter = 0;
42 }
43
44 if (length)
45 xorbuf(m_state.BytePtr() + m_counter, input, length);
46 m_counter += (unsigned int)length;
47}
48
50{
51 std::memset(m_state, 0, m_state.SizeInBytes());
52 m_counter = 0;
53}
54
55void Keccak::TruncatedFinal(byte *hash, size_t size)
56{
57 CRYPTOPP_ASSERT(hash != NULLPTR);
58 ThrowIfInvalidTruncatedSize(size);
59
60 m_state.BytePtr()[m_counter] ^= 0x01;
61 m_state.BytePtr()[r()-1] ^= 0x80;
62 KeccakF1600(m_state);
63 std::memcpy(hash, m_state, size);
64 Restart();
65}
66
67NAMESPACE_END
void TruncatedFinal(byte *hash, size_t size)
Computes the hash of the current message.
Definition keccak.cpp:55
void Restart()
Restart the hash.
Definition keccak.cpp:49
void Update(const byte *input, size_t length)
Updates a hash with additional input.
Definition keccak.cpp:28
size_type SizeInBytes() const
Provides the number of bytes in the SecBlock.
Definition secblock.h:885
byte * BytePtr()
Provides a byte pointer to the first element in the memory block.
Definition secblock.h:876
unsigned long long word64
64-bit unsigned datatype
Definition config_int.h:101
Classes for Keccak message digests.
CRYPTOPP_DLL void xorbuf(byte *buf, const byte *mask, size_t count)
Performs an XOR of a buffer with a mask.
Crypto++ library namespace.
Precompiled header file.
#define CRYPTOPP_ASSERT(exp)
Debugging and diagnostic assertion.
Definition trap.h:68