/* * hmac.c: routines to compute HMAC-SHA-1/224/256/384/512 digests * * Ref: FIPS PUB 198 The Keyed-Hash Message Authentication Code * * Copyright (C) 2003-2007 Mark Shelor, All Rights Reserved * * Version: 5.45 * Tue Jun 26 02:36:00 MST 2007 * */#include <stdio.h>#include <stdlib.h>#include <string.h>#include "hmac.h"#include "sha.h"/* hmacopen: creates a new HMAC-SHA digest object */HMAC *hmacopen(int alg, unsigned char *key, unsigned int keylen){	unsigned int i;	HMAC *h;	SHA_newz(0, h, 1, HMAC);	if (h == NULL)		return(NULL);	if ((h->isha = shaopen(alg)) == NULL) {		SHA_free(h);		return(NULL);	}	if ((h->osha = shaopen(alg)) == NULL) {		shaclose(h->isha);		SHA_free(h);		return(NULL);	}	if (keylen <= h->osha->blocksize / 8)		memcpy(h->key, key, keylen);	else {		if ((h->ksha = shaopen(alg)) == NULL) {			shaclose(h->isha);			shaclose(h->osha);			SHA_free(h);			return(NULL);		}		shawrite(key, keylen * 8, h->ksha);		shafinish(h->ksha);		memcpy(h->key, shadigest(h->ksha), h->ksha->digestlen);		shaclose(h->ksha);	}	for (i = 0; i < h->osha->blocksize / 8; i++)		h->key[i] ^= 0x5c;	shawrite(h->key, h->osha->blocksize, h->osha);	for (i = 0; i < h->isha->blocksize / 8; i++)		h->key[i] ^= (0x5c ^ 0x36);	shawrite(h->key, h->isha->blocksize, h->isha);	memset(h->key, 0, sizeof(h->key));	return(h);}/* hmacwrite: triggers a state update using data in bitstr/bitcnt */unsigned long hmacwrite(unsigned char *bitstr, unsigned long bitcnt, HMAC *h){	return(shawrite(bitstr, bitcnt, h->isha));}/* hmacfinish: computes final digest state */void hmacfinish(HMAC *h){	shafinish(h->isha);	shawrite(shadigest(h->isha), h->isha->digestlen * 8, h->osha);	shaclose(h->isha);	shafinish(h->osha);}/* hmacdigest: returns pointer to digest (binary) */unsigned char *hmacdigest(HMAC *h){	return(shadigest(h->osha));}/* hmachex: returns pointer to digest (hexadecimal) */char *hmachex(HMAC *h){	return(shahex(h->osha));}/* hmacbase64: returns pointer to digest (Base 64) */char *hmacbase64(HMAC *h){	return(shabase64(h->osha));}/* hmacclose: de-allocates digest object */int hmacclose(HMAC *h){	shaclose(h->osha);	if (h != NULL) {		memset(h, 0, sizeof(HMAC));		SHA_free(h);	}	return(0);}