RetroArch/sha256.c
2012-01-08 01:12:05 +01:00

198 lines
5.5 KiB
C

/* SSNES - A Super Nintendo Entertainment System (SNES) Emulator frontend for libsnes.
* Copyright (C) 2010-2012 - Hans-Kristian Arntzen
*
* Some code herein may be based on code found in BSNES.
*
* SSNES 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 Found-
* ation, either version 3 of the License, or (at your option) any later version.
*
* SSNES 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 SSNES.
* If not, see <http://www.gnu.org/licenses/>.
*/
// SHA256 implementation from bSNES. Written by valditx.
//
#include "general.h"
#include "sha256.h"
#include <string.h>
#include <stdio.h>
#define SWAP32(x) ((uint32_t)( \
(((uint32_t)(x) & 0x000000ff) << 24) | \
(((uint32_t)(x) & 0x0000ff00) << 8) | \
(((uint32_t)(x) & 0x00ff0000) >> 8) | \
(((uint32_t)(x) & 0xff000000) >> 24) \
))
static inline void store32le(uint32_t *addr, uint32_t data)
{
*addr = is_little_endian() ? data : SWAP32(data);
}
static inline void store32be(uint32_t *addr, uint32_t data)
{
*addr = is_little_endian() ? SWAP32(data) : data;
}
static inline uint32_t load32le(const uint32_t *addr)
{
return is_little_endian() ? *addr : SWAP32(*addr);
}
static inline uint32_t load32be(const uint32_t *addr)
{
return is_little_endian() ? SWAP32(*addr) : *addr;
}
#define LSL32(x, n) ((uint32_t)(x) << (n))
#define LSR32(x, n) ((uint32_t)(x) >> (n))
#define ROR32(x, n) (LSR32(x, n) | LSL32(x, 32 - (n)))
// First 32 bits of the fractional parts of the square roots of the first 8 primes 2..19
static const uint32_t T_H[8] = {
0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19,
};
// First 32 bits of the fractional parts of the cube roots of the first 64 primes 2..311
static const uint32_t T_K[64] = {
0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
};
struct sha256_ctx
{
union
{
uint8_t u8[64];
uint32_t u32[16];
} in;
unsigned inlen;
uint32_t w[64];
uint32_t h[8];
uint64_t len;
};
static void sha256_init(struct sha256_ctx *p)
{
memset(p, 0, sizeof(struct sha256_ctx));
memcpy(p->h, T_H, sizeof(T_H));
}
static void sha256_block(struct sha256_ctx *p)
{
unsigned i;
uint32_t s0, s1;
uint32_t a, b, c, d, e, f, g, h;
uint32_t t1, t2, maj, ch;
for (i = 0; i < 16; i++)
p->w[i] = load32be(p->in.u32 + i);
for (i = 16; i < 64; i++)
{
s0 = ROR32(p->w[i - 15], 7) ^ ROR32(p->w[i - 15], 18) ^ LSR32(p->w[i - 15], 3);
s1 = ROR32(p->w[i - 2], 17) ^ ROR32(p->w[i - 2], 19) ^ LSR32(p->w[i - 2], 10);
p->w[i] = p->w[i - 16] + s0 + p->w[i - 7] + s1;
}
a = p->h[0]; b = p->h[1]; c = p->h[2]; d = p->h[3];
e = p->h[4]; f = p->h[5]; g = p->h[6]; h = p->h[7];
for (i = 0; i < 64; i++)
{
s0 = ROR32(a, 2) ^ ROR32(a, 13) ^ ROR32(a, 22);
maj = (a & b) ^ (a & c) ^ (b & c);
t2 = s0 + maj;
s1 = ROR32(e, 6) ^ ROR32(e, 11) ^ ROR32(e, 25);
ch = (e & f) ^ (~e & g);
t1 = h + s1 + ch + T_K[i] + p->w[i];
h = g; g = f; f = e; e = d + t1;
d = c; c = b; b = a; a = t1 + t2;
}
p->h[0] += a; p->h[1] += b; p->h[2] += c; p->h[3] += d;
p->h[4] += e; p->h[5] += f; p->h[6] += g; p->h[7] += h;
// Next block
p->inlen = 0;
}
static void sha256_chunk(struct sha256_ctx *p, const uint8_t *s, unsigned len)
{
unsigned l;
p->len += len;
while (len)
{
l = 64 - p->inlen;
l = (len < l) ? len : l;
memcpy(p->in.u8 + p->inlen, s, l);
s += l;
p->inlen += l;
len -= l;
if (p->inlen == 64)
sha256_block(p);
}
}
static void sha256_final(struct sha256_ctx *p)
{
uint64_t len;
p->in.u8[p->inlen++] = 0x80;
if (p->inlen > 56)
{
memset(p->in.u8 + p->inlen, 0, 64 - p->inlen);
sha256_block(p);
}
memset(p->in.u8 + p->inlen, 0, 56 - p->inlen);
len = p->len << 3;
store32be(p->in.u32 + 14, len >> 32);
store32be(p->in.u32 + 15, len);
sha256_block(p);
}
static void sha256_subhash(struct sha256_ctx *p, uint32_t *t)
{
for (unsigned i = 0; i < 8; i++)
store32be(t++, p->h[i]);
}
void sha256_hash(char *out, const uint8_t *in, size_t size)
{
struct sha256_ctx sha;
union
{
uint32_t u32[8];
uint8_t u8[32];
} shahash;
sha256_init(&sha);
sha256_chunk(&sha, in, size);
sha256_final(&sha);
sha256_subhash(&sha, shahash.u32);
for (unsigned i = 0; i < 32; i++)
snprintf(out + 2 * i, 3, "%02x", (unsigned)shahash.u8[i]);
}