keccak256.cpp File Reference

Keccak-256 (SHA3 variant) hash implementation for Ethereum. More...

#include "keccak256.h"
#include <string.h>

Include dependency graph for keccak256.cpp:

Go to the source code of this file.

Macros
#define	KECCAK_ROUNDS   24

Functions
static uint64_t	rol (uint64_t x, int s)
	Rotate a 64-bit integer left by s bits.
static void	keccakf (uint64_t st[25])
void	keccak256 (const uint8_t *in, size_t inlen, uint8_t out[32])
	Compute Keccak-256 hash of input data.

Variables
static const uint64_t	keccakf_rndc [24]
static const int8_t	keccakf_rotc [24]
	Keccak-f[1600] permutation on the state array.
static const int8_t	keccakf_piln [24]

Detailed Description

Keccak-256 (SHA3 variant) hash implementation for Ethereum.

Implements Keccak-256 hashing suitable for Ethereum-style hashing, producing a 32-byte digest. This file contains the internal permutation function and the main keccak256 API.

Definition in file keccak256.cpp.

Macro Definition Documentation

KECCAK_ROUNDS

#define KECCAK_ROUNDS   24

Definition at line 19 of file keccak256.cpp.

Referenced by keccakf().

Function Documentation

keccak256()

void keccak256	(	const uint8_t *	in,
		size_t	inlen,
		uint8_t	out[32] )

Compute Keccak-256 hash of input data.

Compute the Keccak-256 hash of a given input buffer.

Parameters

[in]	in	Pointer to input buffer.
[in]	inlen	Length of input buffer in bytes.
[out]	out	Pointer to a 32-byte buffer to store the hash.

Note

The output buffer must be at least 32 bytes long.

This is Ethereum's Keccak-256 (pre-SHA3 standard padding).

Examples

UsdcSigning.ino.

Definition at line 111 of file keccak256.cpp.

References keccakf().

Referenced by setup().

keccakf()

void keccakf ( uint64_t st[25] )

static

Definition at line 63 of file keccak256.cpp.

References KECCAK_ROUNDS, keccakf_piln, keccakf_rndc, keccakf_rotc, and rol().

Referenced by keccak256().

rol()

uint64_t rol ( uint64_t x, int s )

inlinestatic

Rotate a 64-bit integer left by s bits.

Parameters

x	Value to rotate.
s	Number of bits to rotate.

Returns

Rotated value.

Definition at line 44 of file keccak256.cpp.

Referenced by keccakf().

Variable Documentation

keccakf_piln

const int8_t keccakf_piln[24]

static

Initial value:

= {
  10, 7, 11, 17, 18, 3, 5, 16, 8, 21, 24, 4,
  15, 23, 19, 13, 12, 2, 20, 14, 22, 9, 6, 1
}

Definition at line 58 of file keccak256.cpp.

Referenced by keccakf().

keccakf_rndc

const uint64_t keccakf_rndc[24]

static

Initial value:

= {
  0x0000000000000001ULL, 0x0000000000008082ULL,
  0x800000000000808aULL, 0x8000000080008000ULL,
  0x000000000000808bULL, 0x0000000080000001ULL,
  0x8000000080008081ULL, 0x8000000000008009ULL,
  0x000000000000008aULL, 0x0000000000000088ULL,
  0x0000000080008009ULL, 0x000000008000000aULL,
  0x000000008000808bULL, 0x800000000000008bULL,
  0x8000000000008089ULL, 0x8000000000008003ULL,
  0x8000000000008002ULL, 0x8000000000000080ULL,
  0x000000000000800aULL, 0x800000008000000aULL,
  0x8000000080008081ULL, 0x8000000000008080ULL,
  0x0000000080000001ULL, 0x8000000080008008ULL
}

Definition at line 22 of file keccak256.cpp.

Referenced by keccakf().

keccakf_rotc

const int8_t keccakf_rotc[24]

static

Initial value:

= {
  1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 2, 14,
  27, 41, 56, 8, 25, 43, 62, 18, 39, 61, 20, 44
}

Keccak-f[1600] permutation on the state array.

Parameters

st	25-word state array (1600 bits).

This function applies the 24-round Keccak-f permutation on the input state array in-place.

Definition at line 54 of file keccak256.cpp.

Referenced by keccakf().