diff options
Diffstat (limited to 'libdevcore/Keccak256.cpp')
| -rw-r--r-- | libdevcore/Keccak256.cpp | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/libdevcore/Keccak256.cpp b/libdevcore/Keccak256.cpp new file mode 100644 index 00000000..7933fc7e --- /dev/null +++ b/libdevcore/Keccak256.cpp @@ -0,0 +1,186 @@ +/* + This file is part of solidity. + + solidity is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + solidity is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with solidity. If not, see <http://www.gnu.org/licenses/>. +*/ +/** @file SHA3.cpp + * @author Gav Wood <i@gavwood.com> + * @date 2014 + */ + +#include <libdevcore/Keccak256.h> + +#include <cstdint> +#include <cstdio> +#include <cstdlib> +#include <cstring> + +using namespace std; +using namespace dev; + +namespace dev +{ + +namespace +{ + +/** libkeccak-tiny + * + * A single-file implementation of SHA-3 and SHAKE. + * + * Implementor: David Leon Gil + * License: CC0, attribution kindly requested. Blame taken too, + * but not liability. + */ + +/******** The Keccak-f[1600] permutation ********/ + +/*** Constants. ***/ +static const uint8_t rho[24] = \ + { 1, 3, 6, 10, 15, 21, + 28, 36, 45, 55, 2, 14, + 27, 41, 56, 8, 25, 43, + 62, 18, 39, 61, 20, 44}; +static const uint8_t pi[24] = \ + {10, 7, 11, 17, 18, 3, + 5, 16, 8, 21, 24, 4, + 15, 23, 19, 13, 12, 2, + 20, 14, 22, 9, 6, 1}; +static const uint64_t RC[24] = \ + {1ULL, 0x8082ULL, 0x800000000000808aULL, 0x8000000080008000ULL, + 0x808bULL, 0x80000001ULL, 0x8000000080008081ULL, 0x8000000000008009ULL, + 0x8aULL, 0x88ULL, 0x80008009ULL, 0x8000000aULL, + 0x8000808bULL, 0x800000000000008bULL, 0x8000000000008089ULL, 0x8000000000008003ULL, + 0x8000000000008002ULL, 0x8000000000000080ULL, 0x800aULL, 0x800000008000000aULL, + 0x8000000080008081ULL, 0x8000000000008080ULL, 0x80000001ULL, 0x8000000080008008ULL}; + +/*** Helper macros to unroll the permutation. ***/ +#define rol(x, s) (((x) << s) | ((x) >> (64 - s))) +#define REPEAT6(e) e e e e e e +#define REPEAT24(e) REPEAT6(e e e e) +#define REPEAT5(e) e e e e e +#define FOR5(v, s, e) \ + v = 0; \ + REPEAT5(e; v += s;) + +/*** Keccak-f[1600] ***/ +static inline void keccakf(void* state) { + uint64_t* a = (uint64_t*)state; + uint64_t b[5] = {0}; + + for (int i = 0; i < 24; i++) + { + uint8_t x, y; + // Theta + FOR5(x, 1, + b[x] = 0; + FOR5(y, 5, + b[x] ^= a[x + y]; )) + FOR5(x, 1, + FOR5(y, 5, + a[y + x] ^= b[(x + 4) % 5] ^ rol(b[(x + 1) % 5], 1); )) + // Rho and pi + uint64_t t = a[1]; + x = 0; + REPEAT24(b[0] = a[pi[x]]; + a[pi[x]] = rol(t, rho[x]); + t = b[0]; + x++; ) + // Chi + FOR5(y, + 5, + FOR5(x, 1, + b[x] = a[y + x];) + FOR5(x, 1, + a[y + x] = b[x] ^ ((~b[(x + 1) % 5]) & b[(x + 2) % 5]); )) + // Iota + a[0] ^= RC[i]; + } +} + +/******** The FIPS202-defined functions. ********/ + +/*** Some helper macros. ***/ + +#define _(S) do { S } while (0) +#define FOR(i, ST, L, S) \ + _(for (size_t i = 0; i < L; i += ST) { S; }) +#define mkapply_ds(NAME, S) \ + static inline void NAME(uint8_t* dst, \ + const uint8_t* src, \ + size_t len) { \ + FOR(i, 1, len, S); \ + } +#define mkapply_sd(NAME, S) \ + static inline void NAME(const uint8_t* src, \ + uint8_t* dst, \ + size_t len) { \ + FOR(i, 1, len, S); \ + } + +mkapply_ds(xorin, dst[i] ^= src[i]) // xorin +mkapply_sd(setout, dst[i] = src[i]) // setout + +#define P keccakf +#define Plen 200 + +// Fold P*F over the full blocks of an input. +#define foldP(I, L, F) \ + while (L >= rate) { \ + F(a, I, rate); \ + P(a); \ + I += rate; \ + L -= rate; \ + } + +/** The sponge-based hash construction. **/ +inline void hash( + uint8_t* out, + size_t outlen, + const uint8_t* in, + size_t inlen, + size_t rate, + uint8_t delim +) +{ + uint8_t a[Plen] = {0}; + // Absorb input. + foldP(in, inlen, xorin); + // Xor in the DS and pad frame. + a[inlen] ^= delim; + a[rate - 1] ^= 0x80; + // Xor in the last block. + xorin(a, in, inlen); + // Apply P + P(a); + // Squeeze output. + foldP(out, outlen, setout); + setout(a, out, outlen); + memset(a, 0, 200); +} + +} + +h256 keccak256(bytesConstRef _input) +{ + h256 output; + // Parameters used: + // The 0x01 is the specific padding for keccak (sha3 uses 0x06) and + // the way the round size (or window or whatever it was) is calculated. + // 200 - (256 / 4) is the "rate" + hash(output.data(), output.size, _input.data(), _input.size(), 200 - (256 / 4), 0x01); + return output; +} + +} |