/* 
 * SHA-1 hash in C
 * Copyright (c) 2012 Nayuki Minase
 * 
 * http://nayuki.eigenstate.org/page/fast-sha1-hash-implementation-in-x86-assembly
 */


#include <stdint.h>


#define SCHEDULE(i)  \
	temp = schedule[(i-3)&0xF] ^ schedule[(i-8)&0xF] ^ schedule[(i-14)&0xF] ^ schedule[(i-16)&0xF];  \
	schedule[i & 0xF] = temp << 1 | temp >> 31;

#define ROUND0a(a,b,c,d,e,i)  \
	schedule[i] = (block[i] << 24) | ((block[i] & 0xFF00) << 8) | ((block[i] >> 8) & 0xFF00) | (block[i] >> 24);  \
	ROUNDTAIL(a, b, e, ((b & c) | (~b & d)), i, 0x5A827999)

#define ROUND0b(a,b,c,d,e,i)  \
	SCHEDULE(i)  \
	ROUNDTAIL(a, b, e, ((b & c) | (~b & d)), i, 0x5A827999)

#define ROUND1(a,b,c,d,e,i)  \
	SCHEDULE(i)  \
	ROUNDTAIL(a, b, e, (b ^ c ^ d), i, 0x6ED9EBA1)

#define ROUND2(a,b,c,d,e,i)  \
	SCHEDULE(i)  \
	ROUNDTAIL(a, b, e, ((b & c) ^ (b & d) ^ (c & d)), i, 0x8F1BBCDC)

#define ROUND3(a,b,c,d,e,i)  \
	SCHEDULE(i)  \
	ROUNDTAIL(a, b, e, (b ^ c ^ d), i, 0xCA62C1D6)

#define ROUNDTAIL(a,b,e,f,i,k)  \
	e += (a << 5 | a >> 27) + f + k + schedule[i & 0xF];  \
	b = b << 30 | b >> 2;

void sha1_compress(uint32_t *state, uint32_t *block) {
	uint32_t a = state[0];
	uint32_t b = state[1];
	uint32_t c = state[2];
	uint32_t d = state[3];
	uint32_t e = state[4];
	
	uint32_t schedule[16];
	uint32_t temp;
	ROUND0a(a, b, c, d, e,  0)
	ROUND0a(e, a, b, c, d,  1)
	ROUND0a(d, e, a, b, c,  2)
	ROUND0a(c, d, e, a, b,  3)
	ROUND0a(b, c, d, e, a,  4)
	ROUND0a(a, b, c, d, e,  5)
	ROUND0a(e, a, b, c, d,  6)
	ROUND0a(d, e, a, b, c,  7)
	ROUND0a(c, d, e, a, b,  8)
	ROUND0a(b, c, d, e, a,  9)
	ROUND0a(a, b, c, d, e, 10)
	ROUND0a(e, a, b, c, d, 11)
	ROUND0a(d, e, a, b, c, 12)
	ROUND0a(c, d, e, a, b, 13)
	ROUND0a(b, c, d, e, a, 14)
	ROUND0a(a, b, c, d, e, 15)
	ROUND0b(e, a, b, c, d, 16)
	ROUND0b(d, e, a, b, c, 17)
	ROUND0b(c, d, e, a, b, 18)
	ROUND0b(b, c, d, e, a, 19)
	ROUND1(a, b, c, d, e, 20)
	ROUND1(e, a, b, c, d, 21)
	ROUND1(d, e, a, b, c, 22)
	ROUND1(c, d, e, a, b, 23)
	ROUND1(b, c, d, e, a, 24)
	ROUND1(a, b, c, d, e, 25)
	ROUND1(e, a, b, c, d, 26)
	ROUND1(d, e, a, b, c, 27)
	ROUND1(c, d, e, a, b, 28)
	ROUND1(b, c, d, e, a, 29)
	ROUND1(a, b, c, d, e, 30)
	ROUND1(e, a, b, c, d, 31)
	ROUND1(d, e, a, b, c, 32)
	ROUND1(c, d, e, a, b, 33)
	ROUND1(b, c, d, e, a, 34)
	ROUND1(a, b, c, d, e, 35)
	ROUND1(e, a, b, c, d, 36)
	ROUND1(d, e, a, b, c, 37)
	ROUND1(c, d, e, a, b, 38)
	ROUND1(b, c, d, e, a, 39)
	ROUND2(a, b, c, d, e, 40)
	ROUND2(e, a, b, c, d, 41)
	ROUND2(d, e, a, b, c, 42)
	ROUND2(c, d, e, a, b, 43)
	ROUND2(b, c, d, e, a, 44)
	ROUND2(a, b, c, d, e, 45)
	ROUND2(e, a, b, c, d, 46)
	ROUND2(d, e, a, b, c, 47)
	ROUND2(c, d, e, a, b, 48)
	ROUND2(b, c, d, e, a, 49)
	ROUND2(a, b, c, d, e, 50)
	ROUND2(e, a, b, c, d, 51)
	ROUND2(d, e, a, b, c, 52)
	ROUND2(c, d, e, a, b, 53)
	ROUND2(b, c, d, e, a, 54)
	ROUND2(a, b, c, d, e, 55)
	ROUND2(e, a, b, c, d, 56)
	ROUND2(d, e, a, b, c, 57)
	ROUND2(c, d, e, a, b, 58)
	ROUND2(b, c, d, e, a, 59)
	ROUND3(a, b, c, d, e, 60)
	ROUND3(e, a, b, c, d, 61)
	ROUND3(d, e, a, b, c, 62)
	ROUND3(c, d, e, a, b, 63)
	ROUND3(b, c, d, e, a, 64)
	ROUND3(a, b, c, d, e, 65)
	ROUND3(e, a, b, c, d, 66)
	ROUND3(d, e, a, b, c, 67)
	ROUND3(c, d, e, a, b, 68)
	ROUND3(b, c, d, e, a, 69)
	ROUND3(a, b, c, d, e, 70)
	ROUND3(e, a, b, c, d, 71)
	ROUND3(d, e, a, b, c, 72)
	ROUND3(c, d, e, a, b, 73)
	ROUND3(b, c, d, e, a, 74)
	ROUND3(a, b, c, d, e, 75)
	ROUND3(e, a, b, c, d, 76)
	ROUND3(d, e, a, b, c, 77)
	ROUND3(c, d, e, a, b, 78)
	ROUND3(b, c, d, e, a, 79)
	
	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;
	state[4] += e;
}