ripemd160.c

/** \file ripemd160.c
  *
  * \brief Calculates RIPEMD-160 hashes.
  *
  * The code here is based on the paper: "RIPEMD-160: A strengthened
  * version of RIPEMD" by Hans Dobbertin, Antoon Bosselaers and Bart Preneel,
  * obtained from
  * http://homes.esat.kuleuven.be/~cosicart/pdf/AB-9601/AB-9601.pdf
  * on 30-August-2011.
  * All references in source comments to "the paper" refer to that.
  *
  * This file is licensed as described by the file LICENCE.
  */

#ifdef TEST_RIPEMD160
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "test_helpers.h"
#endif // #ifdef TEST_RIPEMD160

#include "common.h"
#include "hash.h"
#include "ripemd160.h"

/** Selection of message word for main rounds. */
static const uint8_t r1[80] PROGMEM = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
7, 4, 13, 1, 10, 6, 15, 3, 12, 0, 9, 5, 2, 14, 11, 8,
3, 10, 14, 4, 9, 15, 8, 1, 2, 7, 0, 6, 13, 11, 5, 12,
1, 9, 11, 10, 0, 8, 12, 4, 13, 3, 7, 15, 14, 5, 6, 2,
4, 0, 5, 9, 7, 12, 2, 10, 14, 1, 3, 8, 11, 6, 15, 13};

/** Selection of message word for parallel rounds. */
static const uint8_t r2[80] PROGMEM = {
5, 14, 7, 0, 9, 2, 11, 4, 13, 6, 15, 8, 1, 10, 3, 12,
6, 11, 3, 7, 0, 13, 5, 10, 14, 15, 8, 12, 4, 9, 1, 2,
15, 5, 1, 3, 7, 14, 6, 9, 11, 8, 12, 2, 10, 0, 4, 13,
8, 6, 4, 1, 3, 11, 15, 0, 5, 12, 2, 13, 9, 7, 10, 14,
12, 15, 10, 4, 1, 5, 8, 7, 6, 2, 13, 14, 0, 3, 9, 11};

/** Amount of rotate left for main rounds. */
static const uint8_t s1[80] PROGMEM = {
11, 14, 15, 12, 5, 8, 7, 9, 11, 13, 14, 15, 6, 7, 9, 8,
7, 6, 8, 13, 11, 9, 7, 15, 7, 12, 15, 9, 11, 7, 13, 12,
11, 13, 6, 7, 14, 9, 13, 15, 14, 8, 13, 6, 5, 12, 7, 5,
11, 12, 14, 15, 14, 15, 9, 8, 9, 14, 5, 6, 8, 6, 5, 12,
9, 15, 5, 11, 6, 8, 13, 12, 5, 12, 13, 14, 11, 8, 5, 6};

/** Amount of rotate left for parallel rounds. */
static const uint8_t s2[80] PROGMEM = {
8, 9, 9, 11, 13, 15, 15, 5, 7, 7, 8, 11, 14, 14, 12, 6,
9, 13, 15, 7, 12, 8, 9, 11, 7, 7, 12, 7, 6, 15, 13, 11,
9, 7, 15, 11, 8, 6, 6, 14, 12, 13, 5, 14, 13, 13, 7, 5,
15, 5, 8, 11, 14, 14, 6, 14, 6, 9, 12, 9, 12, 5, 15, 8,
8, 5, 12, 9, 12, 5, 14, 6, 8, 13, 6, 5, 15, 13, 11, 11};

/** Cyclic shift left (rotate left).
  * \param x The integer to rotate left.
  * \param n Number of times to rotate left.
  * \return The rotated integer.
  */
static uint32_t rol(uint32_t x, uint8_t n)
{
	return (x << n) | (x >> (32 - n));
}

/** First non-linear (at bit level) function.
  * \param x First input integer.
  * \param y Second input integer.
  * \param z Third input integer.
  * \return Non-linear combination of x, y and z.
  */
static uint32_t f0(uint32_t x, uint32_t y, uint32_t z)
{
	return x ^ y ^ z;
}

/** Second non-linear (at bit level) function.
  * \param x First input integer.
  * \param y Second input integer.
  * \param z Third input integer.
  * \return Non-linear combination of x, y and z.
  */
static uint32_t f1(uint32_t x, uint32_t y, uint32_t z)
{
	return (x & y) | (~x & z);
}

/** Third non-linear (at bit level) function.
  * \param x First input integer.
  * \param y Second input integer.
  * \param z Third input integer.
  * \return Non-linear combination of x, y and z.
  */
static uint32_t f2(uint32_t x, uint32_t y, uint32_t z)
{
	return (x | ~y) ^ z;
}

/** Fourth non-linear (at bit level) function.
  * \param x First input integer.
  * \param y Second input integer.
  * \param z Third input integer.
  * \return Non-linear combination of x, y and z.
  */
static uint32_t f3(uint32_t x, uint32_t y, uint32_t z)
{
	return (x & z) | (y & ~z);
}

/** Fifth non-linear (at bit level) function.
  * \param x First input integer.
  * \param y Second input integer.
  * \param z Third input integer.
  * \return Non-linear combination of x, y and z.
  */
static uint32_t f4(uint32_t x, uint32_t y, uint32_t z)
{
	return x ^ (y | ~z);
}

/** Update hash value based on the contents of a full message buffer.
  * This is an implementation of HashState#hashBlock().
  * \param hs The hash state to update.
  */
static void ripemd160Block(HashState *hs)
{
	// 1 = unprimed, 2 = primed.
	// A to E and T are the variables used in the pseudo-code of Appendix A
	// of the paper.
	// K is the "added constant" for that round.
	// R is the return value of the relevant non-linear at bit level
	// function.
	uint32_t A1, B1, C1, D1, E1;
	uint32_t A2, B2, C2, D2, E2;
	uint32_t T;
	uint32_t K1, K2, R1, R2;
	uint8_t j;
	uint8_t fn_selector;

	A1 = hs->h[0];
	A2 = A1;
	B1 = hs->h[1];
	B2 = B1;
	C1 = hs->h[2];
	C2 = C1;
	D1 = hs->h[3];
	D2 = D1;
	E1 = hs->h[4];
	E2 = E1;
	for (j = 0; j < 80; j++)
	{
		fn_selector = (uint8_t)(j >> 4);
		switch(fn_selector)
		{
		case 0:
			R1 = f0(B1, C1, D1);
			R2 = f4(B2, C2, D2);
			K1 = 0x00000000;
			K2 = 0x50a28be6;
			break;
		case 1:
			R1 = f1(B1, C1, D1);
			R2 = f3(B2, C2, D2);
			K1 = 0x5a827999;
			K2 = 0x5c4dd124;
			break;
		case 2:
			R1 = f2(B1, C1, D1);
			R2 = f2(B2, C2, D2);
			K1 = 0x6ed9eba1;
			K2 = 0x6d703ef3;
			break;
		case 3:
			R1 = f3(B1, C1, D1);
			R2 = f1(B2, C2, D2);
			K1 = 0x8f1bbcdc;
			K2 = 0x7a6d76e9;
			break;
		default:
			R1 = f4(B1, C1, D1);
			R2 = f0(B2, C2, D2);
			K1 = 0xa953fd4e;
			K2 = 0x00000000;
			break;
		}
		T = rol(A1 + R1 + hs->m[LOOKUP_BYTE(r1[j])] + K1, LOOKUP_BYTE(s1[j])) + E1;
		A1 = E1;
		E1 = D1;
		D1 = rol(C1, 10);
		C1 = B1;
		B1 = T;
		T = rol(A2 + R2 + hs->m[LOOKUP_BYTE(r2[j])] + K2, LOOKUP_BYTE(s2[j])) + E2;
		A2 = E2;
		E2 = D2;
		D2 = rol(C2, 10);
		C2 = B2;
		B2 = T;
	}
	T = hs->h[1] + C1 + D2;
	hs->h[1] = hs->h[2] + D1 + E2;
	hs->h[2] = hs->h[3] + E1 + A2;
	hs->h[3] = hs->h[4] + A1 + B2;
	hs->h[4] = hs->h[0] + B1 + C2;
	hs->h[0] = T;
}

/** Begin calculating hash for new message.
  * \param hs The hash state to initialise.
  */
void ripemd160Begin(HashState *hs)
{
	hs->message_length = 0;
	hs->hashBlock = ripemd160Block;
	hs->is_big_endian = false;
	hs->h[0] = 0x67452301;
	hs->h[1] = 0xefcdab89;
	hs->h[2] = 0x98badcfe;
	hs->h[3] = 0x10325476;
	hs->h[4] = 0xc3d2e1f0;
	clearM(hs);
}

/** Add one more byte to the message buffer and call ripemd160Block()
  * if the message buffer is full.
  * \param hs The hash state to act on. The hash state must be one that has
  *           been initialised using ripemd160Begin() at some time in the
  *           past.
  * \param byte The byte to add.
  */
void ripemd160WriteByte(HashState *hs, uint8_t byte)
{
	hashWriteByte(hs, byte);
}

/** Finalise the hashing of a message by writing appropriate padding and
  * length bytes.
  * \param hs The hash state to act on. The hash state must be one that has
  *           been initialised using ripemd160Begin() at some time in the
  *           past.
  */
void ripemd160Finish(HashState *hs)
{
	hashFinish(hs);
}

#ifdef TEST_RIPEMD160

/** Where hash value will be stored after ripemd160() returns. */
static uint32_t h[5];

/** Calculate RIPEMD-160 hash of a message. The result is returned in #h.
  * \param message The message to calculate the hash of. This must be a byte
  *                array of the size specified by length.
  * \param length The length (in bytes) of the message.
  */
static void ripemd160(uint8_t *message, uint32_t length)
{
	uint32_t i;
	HashState hs;

	ripemd160Begin(&hs);
	for (i = 0; i < length; i++)
	{
		ripemd160WriteByte(&hs, message[i]);
	}
	ripemd160Finish(&hs);
	memcpy(h, hs.h, 20);
}

/** Number of tests, not including million "a" test. All the tests
  * (including the million "a" test) are from Appendix B of the paper. */
#define NUMTESTS 8

/** Test messages. */
static const char *test_strings[NUMTESTS] = {
"",
"a",
"abc",
"message digest",
"abcdefghijklmnopqrstuvwxyz",
"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq",
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
"12345678901234567890123456789012345678901234567890123456789012345678901234567890"};

/** RIPEMD-160 hashes of test messages. */
static const uint32_t test_hashes[5 * NUMTESTS] = {
0x9c1185a5, 0xc5e9fc54, 0x61280897, 0x7ee8f548, 0xb2258d31,
0x0bdc9d2d, 0x256b3ee9, 0xdaae347b, 0xe6f4dc83, 0x5a467ffe,
0x8eb208f7, 0xe05d987a, 0x9b044a8e, 0x98c6b087, 0xf15a0bfc,
0x5d0689ef, 0x49d2fae5, 0x72b881b1, 0x23a85ffa, 0x21595f36,
0xf71c2710, 0x9c692c1b, 0x56bbdceb, 0x5b9d2865, 0xb3708dbc,
0x12a05338, 0x4a9c0c88, 0xe405a06c, 0x27dcf49a, 0xda62eb2b,
0xb0e20b6e, 0x31166402, 0x86ed3a87, 0xa5713079, 0xb21f5189,
0x9b752e45, 0x573d4b39, 0xf4dbd332, 0x3cab82bf, 0x63326bfb};

int main(void)
{
	int i;
	char *str;
	uint32_t *compare_h;

	initTests(__FILE__);

	for (i = 0; i < NUMTESTS; i++)
	{
		str = (char *)test_strings[i];
		ripemd160((uint8_t *)str, strlen(str));
		compare_h = (uint32_t *)&(test_hashes[i * 5]);
		if (!memcmp(h, compare_h, 20))
		{
			//printf("%08x%08x%08x%08x%08x\n", h[0], h[1], h[2], h[3], h[4]);
			reportSuccess();
		}
		else
		{
			printf("Test number %d failed\n", i + 1);
			printf("String: %s\n", str);
			reportFailure();
		}
	}

	// Million "a" test.
	str = malloc(1000000);
	memset(str, 'a', 1000000);
	ripemd160((uint8_t *)str, 1000000);
	free(str);
	if ((h[0] == 0x52783243) && (h[1] == 0xc1697bdb)
		&& (h[2] == 0xe16d37f9) && (h[3] == 0x7f68f083)
		&& (h[4] == 0x25dc1528))
	{
		//printf("%08x%08x%08x%08x%08x\n", h[0], h[1], h[2], h[3], h[4]);
		reportSuccess();
	}
	else
	{
		printf("Million \"a\" test failed\n");
		reportFailure();
	}

	finishTests();
	exit(0);
}

#endif // #ifdef TEST_RIPEMD160