/*

  zip_crypto_openssl.c -- OpenSSL wrapper.

  Copyright (C) 2018-2024 Dieter Baron and Thomas Klausner

  This file is part of libzip, a library to manipulate ZIP archives.

  The authors can be contacted at <info@libzip.org>

  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. The names of the authors may not be used to endorse or promote

  products derived from this software without specific prior

  written permission.

  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``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 AUTHORS 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.

*/

#include <stdlib.h>

#include "zipint.h"

#include "zip_crypto.h"

#include <limits.h>

#include <openssl/rand.h>

#ifdef USE_OPENSSL_3_API

static _zip_crypto_hmac_t *hmac_new() {

    _zip_crypto_hmac_t *hmac = (_zip_crypto_hmac_t *)malloc(sizeof(*hmac));

    if (hmac != NULL) {

        hmac->mac = NULL;

        hmac->ctx = NULL;

    }

    return hmac;

}

static void hmac_free(_zip_crypto_hmac_t *hmac) {

    if (hmac != NULL) {

        if (hmac->ctx != NULL) {

            EVP_MAC_CTX_free(hmac->ctx);

        }

        if (hmac->mac != NULL) {

            EVP_MAC_free(hmac->mac);

        }

        free(hmac);

    }

}

#endif

_zip_crypto_aes_t *_zip_crypto_aes_new(const zip_uint8_t *key, zip_uint16_t key_size, zip_error_t *error) {

    _zip_crypto_aes_t *aes;

    const EVP_CIPHER *cipher_type;

    switch (key_size) {

    case 128:

        cipher_type = EVP_aes_128_ecb();

        break;

    case 192:

        cipher_type = EVP_aes_192_ecb();

        break;

    case 256:

        cipher_type = EVP_aes_256_ecb();

        break;

    default:

        zip_error_set(error, ZIP_ER_INTERNAL, 0);

        return NULL;

    }

#ifdef USE_OPENSSL_1_0_API

    if ((aes = (_zip_crypto_aes_t *)malloc(sizeof(*aes))) == NULL) {

        zip_error_set(error, ZIP_ER_MEMORY, 0);

        return NULL;

    }

    memset(aes, 0, sizeof(*aes));

#else

    if ((aes = EVP_CIPHER_CTX_new()) == NULL) {

        zip_error_set(error, ZIP_ER_MEMORY, 0);

        return NULL;

    }

#endif

    if (EVP_EncryptInit_ex(aes, cipher_type, NULL, key, NULL) != 1) {

#ifdef USE_OPENSSL_1_0_API

        free(aes);

#else

        EVP_CIPHER_CTX_free(aes);

#endif

        zip_error_set(error, ZIP_ER_INTERNAL, 0);

        return NULL;

    }

    return aes;

}

void _zip_crypto_aes_free(_zip_crypto_aes_t *aes) {

    if (aes == NULL) {

        return;

    }

#ifdef USE_OPENSSL_1_0_API

    EVP_CIPHER_CTX_cleanup(aes);

    _zip_crypto_clear(aes, sizeof(*aes));

    free(aes);

#else

    EVP_CIPHER_CTX_free(aes);

#endif

}

bool _zip_crypto_aes_encrypt_block(_zip_crypto_aes_t *aes, const zip_uint8_t *in, zip_uint8_t *out) {

    int len = 0;

    if (EVP_EncryptUpdate(aes, out, &len, in, ZIP_CRYPTO_AES_BLOCK_LENGTH) != 1 || len != ZIP_CRYPTO_AES_BLOCK_LENGTH) {

        return false;

    }

    return true;

}

_zip_crypto_hmac_t *_zip_crypto_hmac_new(const zip_uint8_t *secret, zip_uint64_t secret_length, zip_error_t *error) {

    _zip_crypto_hmac_t *hmac;

    if (secret_length > INT_MAX) {

        zip_error_set(error, ZIP_ER_INVAL, 0);

        return NULL;

    }

#ifdef USE_OPENSSL_3_API

    if ((hmac = hmac_new()) == NULL || (hmac->mac = EVP_MAC_fetch(NULL, "HMAC", "provider=default")) == NULL || (hmac->ctx = EVP_MAC_CTX_new(hmac->mac)) == NULL) {

        hmac_free(hmac);

        zip_error_set(error, ZIP_ER_MEMORY, 0);

        return NULL;

    }

    {

        OSSL_PARAM params[2];

        params[0] = OSSL_PARAM_construct_utf8_string("digest", "SHA1", 0);

        params[1] = OSSL_PARAM_construct_end();

        if (!EVP_MAC_init(hmac->ctx, (const unsigned char *)secret, secret_length, params)) {

            zip_error_set(error, ZIP_ER_INTERNAL, 0);

            hmac_free(hmac);

            return NULL;

        }

    }

#else

#ifdef USE_OPENSSL_1_0_API

    if ((hmac = (_zip_crypto_hmac_t *)malloc(sizeof(*hmac))) == NULL) {

        zip_error_set(error, ZIP_ER_MEMORY, 0);

        return NULL;

    }

    HMAC_CTX_init(hmac);

#else

    if ((hmac = HMAC_CTX_new()) == NULL) {

        zip_error_set(error, ZIP_ER_MEMORY, 0);

        return NULL;

    }

#endif

    if (HMAC_Init_ex(hmac, secret, (int)secret_length, EVP_sha1(), NULL) != 1) {

        zip_error_set(error, ZIP_ER_INTERNAL, 0);

#ifdef USE_OPENSSL_1_0_API

        free(hmac);

#else

        HMAC_CTX_free(hmac);

#endif

        return NULL;

    }

#endif

    return hmac;

}

void _zip_crypto_hmac_free(_zip_crypto_hmac_t *hmac) {

    if (hmac == NULL) {

        return;

    }

#if defined(USE_OPENSSL_3_API)

    hmac_free(hmac);

#elif defined(USE_OPENSSL_1_0_API)

    HMAC_CTX_cleanup(hmac);

    _zip_crypto_clear(hmac, sizeof(*hmac));

    free(hmac);

#else

    HMAC_CTX_free(hmac);

#endif

}

bool _zip_crypto_hmac_output(_zip_crypto_hmac_t *hmac, zip_uint8_t *data) {

#ifdef USE_OPENSSL_3_API

    size_t length = 0;

    return EVP_MAC_final(hmac->ctx, data, &length, ZIP_CRYPTO_SHA1_LENGTH) == 1 && length == ZIP_CRYPTO_SHA1_LENGTH;

#else

    unsigned int length = 0;

    return HMAC_Final(hmac, data, &length) == 1 && length == ZIP_CRYPTO_SHA1_LENGTH;

#endif

}

ZIP_EXTERN bool zip_secure_random(zip_uint8_t *buffer, zip_uint16_t length) {

    return RAND_bytes(buffer, length) == 1;

}