/* $OpenBSD: p_open.c,v 1.18 2017/01/29 17:49:23 beck Exp $ */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * 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 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 acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS 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 AUTHOR OR 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.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <stdio.h>
#include <string.h>

#include <openssl/opensslconf.h>

#ifndef OPENSSL_NO_RSA

#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/objects.h>
#include <openssl/rsa.h>
#include <openssl/x509.h>

int
EVP_OpenInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type,
    const unsigned char *ek, int ekl, const unsigned char *iv, EVP_PKEY *priv)
{
	unsigned char *key = NULL;
	int i, size = 0, ret = 0;

	if (type) {
		EVP_CIPHER_CTX_init(ctx);
		if (!EVP_DecryptInit_ex(ctx, type, NULL, NULL, NULL))
			return 0;
	}

	if (!priv)
		return 1;

	if (priv->type != EVP_PKEY_RSA) {
		EVPerror(EVP_R_PUBLIC_KEY_NOT_RSA);
		goto err;
	}

	size = RSA_size(priv->pkey.rsa);
	key = malloc(size + 2);
	if (key == NULL) {
		/* ERROR */
		EVPerror(ERR_R_MALLOC_FAILURE);
		goto err;
	}

	i = EVP_PKEY_decrypt_old(key, ek, ekl, priv);
	if ((i <= 0) || !EVP_CIPHER_CTX_set_key_length(ctx, i)) {
		/* ERROR */
		goto err;
	}
	if (!EVP_DecryptInit_ex(ctx, NULL, NULL, key, iv))
		goto err;

	ret = 1;

err:
	if (key != NULL)
		explicit_bzero(key, size);
	free(key);
	return (ret);
}

int
EVP_OpenFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
{
	int i;

	i = EVP_DecryptFinal_ex(ctx, out, outl);
	if (i)
		i = EVP_DecryptInit_ex(ctx, NULL, NULL, NULL, NULL);
	return (i);
}
#endif
