/* p12_key.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/pkcs12.h>

#include <openssl/bn.h>

/* Uncomment out this line to get debugging info about key generation */

/*#define DEBUG_KEYGEN*/

#ifdef DEBUG_KEYGEN

#include <openssl/bio.h>

extern BIO *bio_err;

void h__dump (unsigned char *p, int len);

#endif

/* PKCS12 compatible key/IV generation */

#ifndef min

#define min(a,b) ((a) < (b) ? (a) : (b))

#endif

EXPORT_C int PKCS12_key_gen_asc(const char *pass, int passlen, unsigned char *salt,

	     int saltlen, int id, int iter, int n, unsigned char *out,

	     const EVP_MD *md_type)

{

	int ret;

	unsigned char *unipass;

	int uniplen;

	if(!pass) {

		unipass = NULL;

		uniplen = 0;

	} else if (!asc2uni(pass, passlen, &unipass, &uniplen)) {

		PKCS12err(PKCS12_F_PKCS12_KEY_GEN_ASC,ERR_R_MALLOC_FAILURE);

		return 0;

	}

	ret = PKCS12_key_gen_uni(unipass, uniplen, salt, saltlen,

						 id, iter, n, out, md_type);

	if(unipass) {

		OPENSSL_cleanse(unipass, uniplen);	/* Clear password from memory */

		OPENSSL_free(unipass);

	}

	return ret;

}

EXPORT_C int PKCS12_key_gen_uni(unsigned char *pass, int passlen, unsigned char *salt,

	     int saltlen, int id, int iter, int n, unsigned char *out,

	     const EVP_MD *md_type)

{

	unsigned char *B, *D, *I, *p, *Ai;

	int Slen, Plen, Ilen, Ijlen;

	int i, j, u, v;

	BIGNUM *Ij, *Bpl1;	/* These hold Ij and B + 1 */

	EVP_MD_CTX ctx;

#ifdef  DEBUG_KEYGEN

	unsigned char *tmpout = out;

	int tmpn = n;

#endif

#if 0

	if (!pass) {

		PKCS12err(PKCS12_F_PKCS12_KEY_GEN_UNI,ERR_R_PASSED_NULL_PARAMETER);

		return 0;

	}

#endif

	EVP_MD_CTX_init(&ctx);

#ifdef  DEBUG_KEYGEN

	fprintf(stderr, "KEYGEN DEBUG\n");

	fprintf(stderr, "ID %d, ITER %d\n", id, iter);

	fprintf(stderr, "Password (length %d):\n", passlen);

	h__dump(pass, passlen);

	fprintf(stderr, "Salt (length %d):\n", saltlen);

	h__dump(salt, saltlen);

#endif

	v = EVP_MD_block_size (md_type);

	u = EVP_MD_size (md_type);

	D = OPENSSL_malloc (v);

	Ai = OPENSSL_malloc (u);

	B = OPENSSL_malloc (v + 1);

	Slen = v * ((saltlen+v-1)/v);

	if(passlen) Plen = v * ((passlen+v-1)/v);

	else Plen = 0;

	Ilen = Slen + Plen;

	I = OPENSSL_malloc (Ilen);

	Ij = BN_new();

	Bpl1 = BN_new();

	if (!D || !Ai || !B || !I || !Ij || !Bpl1) {

		PKCS12err(PKCS12_F_PKCS12_KEY_GEN_UNI,ERR_R_MALLOC_FAILURE);

		return 0;

	}

	for (i = 0; i < v; i++) D[i] = id;

	p = I;

	for (i = 0; i < Slen; i++) *p++ = salt[i % saltlen];

	for (i = 0; i < Plen; i++) *p++ = pass[i % passlen];

	for (;;) {

		EVP_DigestInit_ex(&ctx, md_type, NULL);

		EVP_DigestUpdate(&ctx, D, v);

		EVP_DigestUpdate(&ctx, I, Ilen);

		EVP_DigestFinal_ex(&ctx, Ai, NULL);

		for (j = 1; j < iter; j++) {

			EVP_DigestInit_ex(&ctx, md_type, NULL);

			EVP_DigestUpdate(&ctx, Ai, u);

			EVP_DigestFinal_ex(&ctx, Ai, NULL);

		}

		memcpy (out, Ai, min (n, u));

		if (u >= n) {

			OPENSSL_free (Ai);

			OPENSSL_free (B);

			OPENSSL_free (D);

			OPENSSL_free (I);

			BN_free (Ij);

			BN_free (Bpl1);

			EVP_MD_CTX_cleanup(&ctx);

#ifdef DEBUG_KEYGEN

			fprintf(stderr, "Output KEY (length %d)\n", tmpn);

			h__dump(tmpout, tmpn);

#endif

			return 1;	

		}

		n -= u;

		out += u;

		for (j = 0; j < v; j++) B[j] = Ai[j % u];

		/* Work out B + 1 first then can use B as tmp space */

		BN_bin2bn (B, v, Bpl1);

		BN_add_word (Bpl1, 1);

		for (j = 0; j < Ilen ; j+=v) {

			BN_bin2bn (I + j, v, Ij);

			BN_add (Ij, Ij, Bpl1);

			BN_bn2bin (Ij, B);

			Ijlen = BN_num_bytes (Ij);

			/* If more than 2^(v*8) - 1 cut off MSB */

			if (Ijlen > v) {

				BN_bn2bin (Ij, B);

				memcpy (I + j, B + 1, v);

#ifndef PKCS12_BROKEN_KEYGEN

			/* If less than v bytes pad with zeroes */

			} else if (Ijlen < v) {

				memset(I + j, 0, v - Ijlen);

				BN_bn2bin(Ij, I + j + v - Ijlen); 

#endif

			} else BN_bn2bin (Ij, I + j);

		}

	}

}

#ifdef DEBUG_KEYGEN

void h__dump (unsigned char *p, int len)

{

	for (; len --; p++) fprintf(stderr, "%02X", *p);

	fprintf(stderr, "\n");	

}

#endif