/*

 * Copyright 1999-2016 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include <stdio.h>

#include <stdlib.h>

#include "internal/cryptlib.h"

#include <openssl/x509.h>

#include <openssl/evp.h>

/*

 * Doesn't do anything now: Builtin PBE algorithms in static table.

 */

void PKCS5_PBE_add(void)

{

}

int PKCS5_PBE_keyivgen(EVP_CIPHER_CTX *cctx, const char *pass, int passlen,

                       ASN1_TYPE *param, const EVP_CIPHER *cipher,

                       const EVP_MD *md, int en_de)

{

    EVP_MD_CTX *ctx;

    unsigned char md_tmp[EVP_MAX_MD_SIZE];

    unsigned char key[EVP_MAX_KEY_LENGTH], iv[EVP_MAX_IV_LENGTH];

    int i;

    PBEPARAM *pbe;

    int saltlen, iter;

    unsigned char *salt;

    int mdsize;

    int rv = 0;

    /* Extract useful info from parameter */

    if (param == NULL || param->type != V_ASN1_SEQUENCE ||

        param->value.sequence == NULL) {

        EVPerr(EVP_F_PKCS5_PBE_KEYIVGEN, EVP_R_DECODE_ERROR);

        return 0;

    }

    pbe = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(PBEPARAM), param);

    if (pbe == NULL) {

        EVPerr(EVP_F_PKCS5_PBE_KEYIVGEN, EVP_R_DECODE_ERROR);

        return 0;

    }

    if (!pbe->iter)

        iter = 1;

    else

        iter = ASN1_INTEGER_get(pbe->iter);

    salt = pbe->salt->data;

    saltlen = pbe->salt->length;

    if (!pass)

        passlen = 0;

    else if (passlen == -1)

        passlen = strlen(pass);

    ctx = EVP_MD_CTX_new();

    if (ctx == NULL) {

        EVPerr(EVP_F_PKCS5_PBE_KEYIVGEN, ERR_R_MALLOC_FAILURE);

        goto err;

    }

    if (!EVP_DigestInit_ex(ctx, md, NULL))

        goto err;

    if (!EVP_DigestUpdate(ctx, pass, passlen))

        goto err;

    if (!EVP_DigestUpdate(ctx, salt, saltlen))

        goto err;

    PBEPARAM_free(pbe);

    if (!EVP_DigestFinal_ex(ctx, md_tmp, NULL))

        goto err;

    mdsize = EVP_MD_size(md);

    if (mdsize < 0)

        return 0;

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

        if (!EVP_DigestInit_ex(ctx, md, NULL))

            goto err;

        if (!EVP_DigestUpdate(ctx, md_tmp, mdsize))

            goto err;

        if (!EVP_DigestFinal_ex(ctx, md_tmp, NULL))

            goto err;

    }

    OPENSSL_assert(EVP_CIPHER_key_length(cipher) <= (int)sizeof(md_tmp));

    memcpy(key, md_tmp, EVP_CIPHER_key_length(cipher));

    OPENSSL_assert(EVP_CIPHER_iv_length(cipher) <= 16);

    memcpy(iv, md_tmp + (16 - EVP_CIPHER_iv_length(cipher)),

           EVP_CIPHER_iv_length(cipher));

    if (!EVP_CipherInit_ex(cctx, cipher, NULL, key, iv, en_de))

        goto err;

    OPENSSL_cleanse(md_tmp, EVP_MAX_MD_SIZE);

    OPENSSL_cleanse(key, EVP_MAX_KEY_LENGTH);

    OPENSSL_cleanse(iv, EVP_MAX_IV_LENGTH);

    rv = 1;

 err:

    EVP_MD_CTX_free(ctx);

    return rv;

}