/* whirlpool.c - Whirlpool cryptographic hash */
/* Jon Mayo - PUBLIC DOMAIN - October 9, 2006 */

/* information taken from:
 * "The WHIRLPOOL Hashing Function", Paulo S.L.M. Barreto, Vincent Rijmen [Whirlpool.pdf]
 *
 * "A Compact FPGA Implementation of the Hash Function Whirlpool", Norber t Pramstaller, Christian Rechberger, and Vincent Rijmen. [p159-pramstaller.pdf]
 */


#include <stdlib.h>
#include <stdint.h>

#ifndef NR
#define NR(x) (sizeof(x)/sizeof*(x))
#endif

#define WHIRLPOOL_DIGEST_SIZE 64 /* in bytes */
#define WHIRLPOOL_ROUNDS 10
struct whirlpool_ctx {
	uint32_t state[WHIRLPOOL_DIGEST_SIZE/4];
	uint32_t block[WHIRLPOOL_DIGEST_SIZE/4];
	uint32_t round[WHIRLPOOL_DIGEST_SIZE/4];
	uint32_t hash[WHIRLPOOL_DIGEST_SIZE/4]; /* hash state */
	uint32_t L[WHIRLPOOL_DIGEST_SIZE/4];
};

/* Whirlpool S-box */
static const unsigned char whirlpool_sbox[256] = {
	0x18, 0x23, 0xc6, 0xe8, 0x87, 0xb8, 0x01, 0x4f, 
	0x36, 0xa6, 0xd2, 0xf5, 0x79, 0x6f, 0x91, 0x52, 
	0x60, 0xbc, 0x9b, 0x8e, 0xa3, 0x0c, 0x7b, 0x35, 
	0x1d, 0xe0, 0xd7, 0xc2, 0x2e, 0x4b, 0xfe, 0x57, 
	0x15, 0x77, 0x37, 0xe5, 0x9f, 0xf0, 0x4a, 0xda, 
	0x58, 0xc9, 0x29, 0x0a, 0xb1, 0xa0, 0x6b, 0x85, 
	0xbd, 0x5d, 0x10, 0xf4, 0xcb, 0x3e, 0x05, 0x67, 
	0xe4, 0x27, 0x41, 0x8b, 0xa7, 0x7d, 0x95, 0xd8, 
	0xfb, 0xee, 0x7c, 0x66, 0xdd, 0x17, 0x47, 0x9e, 
	0xca, 0x2d, 0xbf, 0x07, 0xad, 0x5a, 0x83, 0x33, 
	0x63, 0x02, 0xaa, 0x71, 0xc8, 0x19, 0x49, 0xd9, 
	0xf2, 0xe3, 0x5b, 0x88, 0x9a, 0x26, 0x32, 0xb0, 
	0xe9, 0x0f, 0xd5, 0x80, 0xbe, 0xcd, 0x34, 0x48, 
	0xff, 0x7a, 0x90, 0x5f, 0x20, 0x68, 0x1a, 0xae, 
	0xb4, 0x54, 0x93, 0x22, 0x64, 0xf1, 0x73, 0x12, 
	0x40, 0x08, 0xc3, 0xec, 0xdb, 0xa1, 0x8d, 0x3d, 
	0x97, 0x00, 0xcf, 0x2b, 0x76, 0x82, 0xd6, 0x1b, 
	0xb5, 0xaf, 0x6a, 0x50, 0x45, 0xf3, 0x30, 0xef, 
	0x3f, 0x55, 0xa2, 0xea, 0x65, 0xba, 0x2f, 0xc0, 
	0xde, 0x1c, 0xfd, 0x4d, 0x92, 0x75, 0x06, 0x8a, 
	0xb2, 0xe6, 0x0e, 0x1f, 0x62, 0xd4, 0xa8, 0x96, 
	0xf9, 0xc5, 0x25, 0x59, 0x84, 0x72, 0x39, 0x4c, 
	0x5e, 0x78, 0x38, 0x8c, 0xd1, 0xa5, 0xe2, 0x61, 
	0xb3, 0x21, 0x9c, 0x1e, 0x43, 0xc7, 0xfc, 0x04, 
	0x51, 0x99, 0x6d, 0x0d, 0xfa, 0xdf, 0x7e, 0x24, 
	0x3b, 0xab, 0xce, 0x11, 0x8f, 0x4e, 0xb7, 0xeb, 
	0x3c, 0x81, 0x94, 0xf7, 0xb9, 0x13, 0x2c, 0xd3, 
	0xe7, 0x6e, 0xc4, 0x03, 0x56, 0x44, 0x7f, 0xa9, 
	0x2a, 0xbb, 0xc1, 0x53, 0xdc, 0x0b, 0x9d, 0x6c, 
	0x31, 0x74, 0xf6, 0x46, 0xac, 0x89, 0x14, 0xe1, 
	0x16, 0x3a, 0x69, 0x09, 0x70, 0xb6, 0xd0, 0xed, 
	0xcc, 0x42, 0x98, 0xa4, 0x28, 0x5c, 0xf8, 0x86, 
};

struct whirlpool_ctx *whirlpool_alloc(void);
void whirlpool_free(struct whirlpool_ctx *context);
void whirlpool_init(struct whirlpool_ctx *context);
void whirlpool_update(struct whirlpool_ctx *context, const uint8_t* data, const size_t len);
void whirlpool_final(struct whirlpool_ctx *context, uint8_t digest[WHIRLPOOL_DIGEST_SIZE]);

struct whirlpool_ctx *whirlpool_alloc(void) {
	return calloc(1, sizeof(struct whirlpool_ctx));
}

void whirlpool_free(struct whirlpool_ctx *context) {
	free(context);
}

void whirlpool_init(struct whirlpool_ctx *context) {
	int i;

	/* h0 is 0 */
	for(i=0;i<NR(context->hash);i++) context->hash[i]=0;
}

void whirlpool_update(struct whirlpool_ctx *context, const uint8_t* data, const size_t len) {
	abort(); /* not implemented */
}

void whirlpool_final(struct whirlpool_ctx *context, uint8_t digest[WHIRLPOOL_DIGEST_SIZE]) {
	abort(); /* not implemented */
}

#ifdef STAND_ALONE
#include <stdio.h>

static void make_s_box(void) {
	unsigned char sbox[256];
	/* E, E inverse and R miniboxes */
	const unsigned char
		e[16] = {1, 11, 9, 12, 13, 6, 15, 3, 14, 8, 7, 4, 10, 2, 5, 0}, 
		ei[16] = {15, 0, 13, 7, 11, 14, 5, 10, 9, 2, 12, 1, 3, 4, 8, 6},
		r[16] = {7, 12, 11, 13, 14, 4, 9, 15, 6, 3, 8, 10, 2, 5, 1, 0};
	unsigned u, i;

	/* dump the mini s-boxes */
	printf("e  = ");
	for(i=0;i<16;i++) { printf("%01x", e[i]); }
	printf("\nei = ");
	for(i=0;i<16;i++) { printf("%01x", ei[i]); }
	printf("\nr  = ");
	for(i=0;i<16;i++) { printf("%01x", r[i]); }
	printf("\n");

	for(u=0;u<256;u++) {
		unsigned x,y,c;
		x=e[u>>4];
		y=ei[u&15];
		c=r[x^y];
		sbox[u]=(e[x^c]<<4)|ei[y^c];
	}

	printf("static const unsigned char whirlpool_sbox[256] = {\n");
	for(i=0;i<256;i++) {
		if(i%8==0) printf("\t");
		printf("0x%02x, ", sbox[i]);
		if(i%8==7) printf("\n");
	}
	printf("};\n");
}

static void print_digest(uint8_t digest[WHIRLPOOL_DIGEST_SIZE]) {
	int i;
	for(i=0;i<WHIRLPOOL_DIGEST_SIZE;i++) {
		printf("%02X", digest[i]);
		if(i%32==31) printf("\n");
	}
}

int main(int argc, char **argv) {
	struct whirlpool_ctx *wc;
	uint8_t digest[WHIRLPOOL_DIGEST_SIZE];
	/* dump the s box data */
	make_s_box();

	/* calcuate on some example data */
	wc=whirlpool_alloc();
	whirlpool_init(wc);
	whirlpool_update(wc, (uint8_t*)"The quick brown fox jumps over the lazy dog", 43);
	whirlpool_final(wc, digest);
	whirlpool_free(wc);
	print_digest(digest);
	printf(
		"should be:\n"
		"B97DE512E91E3828B40D2B0FDCE9CEB3C4A71F9BEA8D88E75C4FA854DF36725F\n"
		"D2B52EB6544EDCACD6F8BEDDFEA403CB55AE31F03AD62A5EF54E42EE82C3FB35\n"
	);
}
#endif
/* vim: ts=8 sts=0 sw=8
 */