text: /* p12_mutl.c */
  /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
   * project 1999.
   */
  /* ====================================================================
   * Copyright (c) 1999 The OpenSSL Project.  All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer. 
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. All advertising materials mentioning features or use of this
   *    software must display the following acknowledgment:
   *    "This product includes software developed by the OpenSSL Project
   *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
   *
   * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
   *    endorse or promote products derived from this software without
   *    prior written permission. For written permission, please contact
   *    licensing@OpenSSL.org.
   *
   * 5. Products derived from this software may not be called "OpenSSL"
   *    nor may "OpenSSL" appear in their names without prior written
   *    permission of the OpenSSL Project.
   *
   * 6. Redistributions of any form whatsoever must retain the following
   *    acknowledgment:
   *    "This product includes software developed by the OpenSSL Project
   *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
   *
   * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
   * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
   * OF THE POSSIBILITY OF SUCH DAMAGE.
   * ====================================================================
   *
   * This product includes cryptographic software written by Eric Young
   * (eay@cryptsoft.com).  This product includes software written by Tim
   * Hudson (tjh@cryptsoft.com).
   *
   */
  
  #include <stdio.h>
  #include "cryptlib.h"
  #include <openssl/hmac.h>
  #include <openssl/rand.h>
  #include <openssl/pkcs12.h>
  
  /* Generate a MAC */
  int PKCS12_gen_mac (PKCS12 *p12, const char *pass, int passlen,
  		    unsigned char *mac, unsigned int *maclen)
  {
  	const EVP_MD *md_type;
  	HMAC_CTX hmac;
  	unsigned char key[PKCS12_MAC_KEY_LENGTH], *salt;
  	int saltlen, iter;
  	salt = p12->mac->salt->data;
  	saltlen = p12->mac->salt->length;
  	if (!p12->mac->iter) iter = 1;
  	else iter = ASN1_INTEGER_get (p12->mac->iter);
      	if(!(md_type =
  		 EVP_get_digestbyobj (p12->mac->dinfo->algor->algorithm))) {
  		PKCS12err(PKCS12_F_PKCS12_GEN_MAC,PKCS12_R_UNKNOWN_DIGEST_ALGORITHM);
  		return 0;
  	}
  	if(!PKCS12_key_gen (pass, passlen, salt, saltlen, PKCS12_MAC_ID, iter,
  				 PKCS12_MAC_KEY_LENGTH, key, md_type)) {
  		PKCS12err(PKCS12_F_PKCS12_GEN_MAC,PKCS12_R_KEY_GEN_ERROR);
  		return 0;
  	}
  	HMAC_Init (&hmac, key, PKCS12_MAC_KEY_LENGTH, md_type);
      	HMAC_Update (&hmac, p12->authsafes->d.data->data,
  					 p12->authsafes->d.data->length);
      	HMAC_Final (&hmac, mac, maclen);
  	return 1;
  }
  
  /* Verify the mac */
  int PKCS12_verify_mac (PKCS12 *p12, const char *pass, int passlen)
  {
  	unsigned char mac[EVP_MAX_MD_SIZE];
  	unsigned int maclen;
  	if(p12->mac == NULL) {
  		PKCS12err(PKCS12_F_VERIFY_MAC,PKCS12_R_MAC_ABSENT);
  		return 0;
  	}
  	if (!PKCS12_gen_mac (p12, pass, passlen, mac, &maclen)) {
  		PKCS12err(PKCS12_F_VERIFY_MAC,PKCS12_R_MAC_GENERATION_ERROR);
  		return 0;
  	}
  	if ((maclen != (unsigned int)p12->mac->dinfo->digest->length)
  	|| memcmp (mac, p12->mac->dinfo->digest->data, maclen)) {
  		PKCS12err(PKCS12_F_VERIFY_MAC,PKCS12_R_MAC_VERIFY_ERROR);
  		return 0;
  	}
  	return 1;
  }
  
  /* Set a mac */
  
  int PKCS12_set_mac (PKCS12 *p12, const char *pass, int passlen,
  	     unsigned char *salt, int saltlen, int iter, EVP_MD *md_type)
  {
  	unsigned char mac[EVP_MAX_MD_SIZE];
  	unsigned int maclen;
  
  	if (!md_type) md_type = EVP_sha1();
  	if (PKCS12_setup_mac (p12, iter, salt, saltlen, md_type) ==
  				 	PKCS12_ERROR) {
  		PKCS12err(PKCS12_F_PKCS12_SET_MAC,PKCS12_R_MAC_SETUP_ERROR);
  		return 0;
  	}
  	if (!PKCS12_gen_mac (p12, pass, passlen, mac, &maclen)) {
  		PKCS12err(PKCS12_F_PKCS12_SET_MAC,PKCS12_R_MAC_GENERATION_ERROR);
  		return 0;
  	}
  	if (!(ASN1_OCTET_STRING_set (p12->mac->dinfo->digest, mac, maclen))) {
  		PKCS12err(PKCS12_F_PKCS12_SET_MAC,PKCS12_R_MAC_STRING_SET_ERROR);
  						return 0;
  	}
  	return 1;
  }
  
  /* Set up a mac structure */
  int PKCS12_setup_mac (PKCS12 *p12, int iter, unsigned char *salt, int saltlen,
  	     EVP_MD *md_type)
  {
  	if (!(p12->mac = PKCS12_MAC_DATA_new ())) return PKCS12_ERROR;
  	if (iter > 1) {
  		if(!(p12->mac->iter = ASN1_INTEGER_new())) {
  			PKCS12err(PKCS12_F_PKCS12_SETUP_MAC, ERR_R_MALLOC_FAILURE);
  			return 0;
  		}
  		ASN1_INTEGER_set (p12->mac->iter, iter);
  	}
  	if (!saltlen) saltlen = PKCS12_SALT_LEN;
  	p12->mac->salt->length = saltlen;
  	if (!(p12->mac->salt->data = Malloc (saltlen))) {
  		PKCS12err(PKCS12_F_PKCS12_SETUP_MAC, ERR_R_MALLOC_FAILURE);
  		return 0;
  	}
  	if (!salt) RAND_bytes (p12->mac->salt->data, saltlen);
  	else memcpy (p12->mac->salt->data, salt, saltlen);
  	p12->mac->dinfo->algor->algorithm = OBJ_nid2obj(EVP_MD_type(md_type));
  	if (!(p12->mac->dinfo->algor->parameter = ASN1_TYPE_new())) {
  		PKCS12err(PKCS12_F_PKCS12_SETUP_MAC, ERR_R_MALLOC_FAILURE);
  		return 0;
  	}
  	p12->mac->dinfo->algor->parameter->type = V_ASN1_NULL;
  	
  	return 1;
  }
  