/*

 * Copyright 2017 The OpenSSL Project Authors. All Rights Reserved.

 * Copyright 2017 Ribose Inc. All Rights Reserved.

 * Ported from Ribose contributions from Botan.

 *

 * 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 "internal/cryptlib.h"

#ifndef OPENSSL_NO_SM4

# include <openssl/evp.h>

# include <openssl/modes.h>

# include "internal/sm4.h"

# include "internal/evp_int.h"

typedef struct {

    SM4_KEY ks;

} EVP_SM4_KEY;

static int sm4_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,

                        const unsigned char *iv, int enc)

{

    SM4_set_key(key, EVP_CIPHER_CTX_get_cipher_data(ctx));

    return 1;

}

static void sm4_cbc_encrypt(const unsigned char *in, unsigned char *out,

                            size_t len, const SM4_KEY *key,

                            unsigned char *ivec, const int enc)

{

    if (enc)

        CRYPTO_cbc128_encrypt(in, out, len, key, ivec,

                              (block128_f)SM4_encrypt);

    else

        CRYPTO_cbc128_decrypt(in, out, len, key, ivec,

                              (block128_f)SM4_decrypt);

}

static void sm4_cfb128_encrypt(const unsigned char *in, unsigned char *out,

                               size_t length, const SM4_KEY *key,

                               unsigned char *ivec, int *num, const int enc)

{

    CRYPTO_cfb128_encrypt(in, out, length, key, ivec, num, enc,

                          (block128_f)SM4_encrypt);

}

static void sm4_ecb_encrypt(const unsigned char *in, unsigned char *out,

                            const SM4_KEY *key, const int enc)

{

    if (enc)

        SM4_encrypt(in, out, key);

    else

        SM4_decrypt(in, out, key);

}

static void sm4_ofb128_encrypt(const unsigned char *in, unsigned char *out,

                               size_t length, const SM4_KEY *key,

                               unsigned char *ivec, int *num)

{

    CRYPTO_ofb128_encrypt(in, out, length, key, ivec, num,

                          (block128_f)SM4_encrypt);

}

IMPLEMENT_BLOCK_CIPHER(sm4, ks, sm4, EVP_SM4_KEY, NID_sm4,

                       16, 16, 16, 128, EVP_CIPH_FLAG_DEFAULT_ASN1,

                       sm4_init_key, 0, 0, 0, 0)

static int sm4_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,

                          const unsigned char *in, size_t len)

{

    unsigned int num = EVP_CIPHER_CTX_num(ctx);

    EVP_SM4_KEY *dat = EVP_C_DATA(EVP_SM4_KEY, ctx);

    CRYPTO_ctr128_encrypt(in, out, len, &dat->ks,

                          EVP_CIPHER_CTX_iv_noconst(ctx),

                          EVP_CIPHER_CTX_buf_noconst(ctx), &num,

                          (block128_f)SM4_encrypt);

    EVP_CIPHER_CTX_set_num(ctx, num);

    return 1;

}

static const EVP_CIPHER sm4_ctr_mode = {

    NID_sm4_ctr, 1, 16, 16,

    EVP_CIPH_CTR_MODE,

    sm4_init_key,

    sm4_ctr_cipher,

    NULL,

    sizeof(EVP_SM4_KEY),

    NULL, NULL, NULL, NULL

};

const EVP_CIPHER *EVP_sm4_ctr(void)

{

    return &sm4_ctr_mode;

}

#endif