~drizzle-trunk/drizzle/development

/**

 * @file

 * @brief SHA1 Definitions

 */

/*

 * SHA-1 in C

 * 

 * Copyright (C) 2010 nobody (this is public domain)

 *

 * This file is based on public domain code.

 * Initial source code is in the public domain, 

 * so clarified by Steve Reid <steve@edmweb.com>

 *

 * Test Vectors (from FIPS PUB 180-1)

 * "abc"

 *   A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D

 * "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"

 *   84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1

 * A million repetitions of "a"

 *   34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F

 */

#include <libdrizzle/common.h>

#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))

/*

 * blk0() and blk() perform the initial expand.

 * I got the idea of expanding during the round function from SSLeay

 */

#ifndef WORDS_BIGENDIAN

# define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \

    |(rol(block->l[i],8)&0x00FF00FF))

#else

# define blk0(i) block->l[i]

#endif

#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \

    ^block->l[(i+2)&15]^block->l[i&15],1))

/*

 * (R0+R1), R2, R3, R4 are the different operations (rounds) used in SHA1

 */

#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);

#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);

#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);

#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);

#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);

/*

 * Hash a single 512-bit block. This is the core of the algorithm.

 */

void

SHA1Transform(uint32_t state[5], const uint8_t buffer[SHA1_BLOCK_LENGTH])

{

	uint32_t a, b, c, d, e;

	typedef union {

		uint8_t c[64];

		uint32_t l[16];

	} CHAR64LONG16;

	CHAR64LONG16 realBlock;

	CHAR64LONG16 *block= &realBlock;

	(void)memcpy(block, buffer, SHA1_BLOCK_LENGTH);

	/* Copy context->state[] to working vars */

	a = state[0];

	b = state[1];

	c = state[2];

	d = state[3];

	e = state[4];

	/* 4 rounds of 20 operations each. Loop unrolled. */

	R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);

	R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);

	R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);

	R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);

	R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);

	R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);

	R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);

	R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);

	R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);

	R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);

	R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);

	R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);

	R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);

	R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);

	R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);

	R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);

	R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);

	R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);

	R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);

	R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);

	/* Add the working vars back into context.state[] */

	state[0] += a;

	state[1] += b;

	state[2] += c;

	state[3] += d;

	state[4] += e;

	/* Wipe variables */

	a = b = c = d = e = 0;

}

/*

 * SHA1Init - Initialize new context

 */

void

SHA1Init(SHA1_CTX *context)

{

	/* SHA1 initialization constants */

	context->count = 0;

	context->state[0] = 0x67452301;

	context->state[1] = 0xEFCDAB89;

	context->state[2] = 0x98BADCFE;

	context->state[3] = 0x10325476;

	context->state[4] = 0xC3D2E1F0;

}

/*

 * Run your data through this.

 */

void

SHA1Update(SHA1_CTX *context, const uint8_t *data, size_t len)

{

	size_t i, j;

	j = (size_t)((context->count >> 3) & 63);

	context->count += (len << 3);

	if ((j + len) > 63) {

		(void)memcpy(&context->buffer[j], data, (i = 64-j));

		SHA1Transform(context->state, context->buffer);

		for ( ; i + 63 < len; i += 64)

			SHA1Transform(context->state, (uint8_t *)&data[i]);

		j = 0;

	} else {

		i = 0;

	}

	(void)memcpy(&context->buffer[j], &data[i], len - i);

}

/*

 * Add padding and return the message digest.

 */

void

SHA1Pad(SHA1_CTX *context)

{

	uint8_t finalcount[8];

	u_int i;

	for (i = 0; i < 8; i++) {

		finalcount[i] = (uint8_t)((context->count >>

		    ((7 - (i & 7)) * 8)) & 255);	/* Endian independent */

	}

	SHA1Update(context, (uint8_t *)"\200", 1);

	while ((context->count & 504) != 448)

		SHA1Update(context, (uint8_t *)"\0", 1);

	SHA1Update(context, finalcount, 8); /* Should cause a SHA1Transform() */

}

void

SHA1Final(uint8_t digest[SHA1_DIGEST_LENGTH], SHA1_CTX *context)

{

	u_int i;

	SHA1Pad(context);

	if (digest) {

		for (i = 0; i < SHA1_DIGEST_LENGTH; i++) {

			digest[i] = (uint8_t)

			   ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);

		}

		memset(context, 0, sizeof(*context));

	}

}