/*  $OpenBSD: e_sm4.c,v 1.1 2019/03/17 17:42:37 tb Exp $  */

/*

 * Copyright (c) 2017, 2019 Ribose Inc

 *

 * Permission to use, copy, modify, and/or distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */

#include <openssl/opensslconf.h>

#ifndef OPENSSL_NO_SM4

#include <openssl/evp.h>

#include <openssl/modes.h>

#include <openssl/sm4.h>

#include "evp_locl.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, ctx->cipher_data);

  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, NULL, 0, 0, 0)

static int

sm4_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, const unsigned char *in,

    size_t len)

{

  EVP_SM4_KEY *key = EVP_C_DATA(EVP_SM4_KEY, ctx);

  CRYPTO_ctr128_encrypt(in, out, len, &key->ks, ctx->iv, ctx->buf,

      &ctx->num, (block128_f)SM4_encrypt);

  return 1;

}

static const EVP_CIPHER sm4_ctr_mode = {

  .nid = NID_sm4_ctr,

  .block_size = 1,

  .key_len = 16,

  .iv_len = 16,

  .flags = EVP_CIPH_CTR_MODE,

  .init = sm4_init_key,

  .do_cipher = sm4_ctr_cipher,

  .cleanup = NULL,

  .ctx_size = sizeof(EVP_SM4_KEY),

  .set_asn1_parameters = NULL,

  .get_asn1_parameters = NULL,

  .ctrl = NULL,

  .app_data = NULL,

};

const EVP_CIPHER *

EVP_sm4_ctr(void)

{

  return &sm4_ctr_mode;

}

#endif