// SPDX-License-Identifier: GPL-2.0-or-later

  /*

   * Cryptographic API.
   *
   * DES & Triple DES EDE Cipher Algorithms.
   *

   * Copyright (c) 2005 Dag Arne Osvik <da@osvik.no>

   */

  #include <asm/byteorder.h>

  #include <linux/bitops.h>

  #include <linux/init.h>
  #include <linux/module.h>

  #include <linux/errno.h>

  #include <linux/crypto.h>

  #include <crypto/internal/des.h>

  static int des_setkey(struct crypto_tfm *tfm, const u8 *key,

  		      unsigned int keylen)

  {

  	struct des_ctx *dctx = crypto_tfm_ctx(tfm);

  	int err;

  	err = des_expand_key(dctx, key, keylen);
  	if (err == -ENOKEY) {
  		if (crypto_tfm_get_flags(tfm) & CRYPTO_TFM_REQ_FORBID_WEAK_KEYS)
  			err = -EINVAL;
  		else
  			err = 0;

  	}

  	if (err) {
  		memset(dctx, 0, sizeof(*dctx));
  		crypto_tfm_set_flags(tfm, CRYPTO_TFM_RES_WEAK_KEY);
  	}
  	return err;

  }

  static void crypto_des_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)

  {

  	const struct des_ctx *dctx = crypto_tfm_ctx(tfm);

  	des_encrypt(dctx, dst, src);

  }

  static void crypto_des_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)

  {

  	const struct des_ctx *dctx = crypto_tfm_ctx(tfm);

  	des_decrypt(dctx, dst, src);

  }

  static int des3_ede_setkey(struct crypto_tfm *tfm, const u8 *key,
  			   unsigned int keylen)
  {
  	struct des3_ede_ctx *dctx = crypto_tfm_ctx(tfm);

  	int err;

  	err = des3_ede_expand_key(dctx, key, keylen);
  	if (err == -ENOKEY) {
  		if (crypto_tfm_get_flags(tfm) & CRYPTO_TFM_REQ_FORBID_WEAK_KEYS)
  			err = -EINVAL;
  		else
  			err = 0;
  	}

  	if (err) {
  		memset(dctx, 0, sizeof(*dctx));
  		crypto_tfm_set_flags(tfm, CRYPTO_TFM_RES_WEAK_KEY);
  	}
  	return err;

  }

  static void crypto_des3_ede_encrypt(struct crypto_tfm *tfm, u8 *dst,
  				    const u8 *src)

  {

  	const struct des3_ede_ctx *dctx = crypto_tfm_ctx(tfm);

  	des3_ede_encrypt(dctx, dst, src);

  }

  static void crypto_des3_ede_decrypt(struct crypto_tfm *tfm, u8 *dst,
  				    const u8 *src)

  {

  	const struct des3_ede_ctx *dctx = crypto_tfm_ctx(tfm);

  	des3_ede_decrypt(dctx, dst, src);

  }

  static struct crypto_alg des_algs[2] = { {

  	.cra_name		=	"des",

  	.cra_driver_name	=	"des-generic",
  	.cra_priority		=	100,

  	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
  	.cra_blocksize		=	DES_BLOCK_SIZE,
  	.cra_ctxsize		=	sizeof(struct des_ctx),
  	.cra_module		=	THIS_MODULE,

  	.cra_u			=	{ .cipher = {
  	.cia_min_keysize	=	DES_KEY_SIZE,
  	.cia_max_keysize	=	DES_KEY_SIZE,

  	.cia_setkey		=	des_setkey,

  	.cia_encrypt		=	crypto_des_encrypt,
  	.cia_decrypt		=	crypto_des_decrypt } }

  }, {

  	.cra_name		=	"des3_ede",

  	.cra_driver_name	=	"des3_ede-generic",
  	.cra_priority		=	100,

  	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
  	.cra_blocksize		=	DES3_EDE_BLOCK_SIZE,
  	.cra_ctxsize		=	sizeof(struct des3_ede_ctx),
  	.cra_module		=	THIS_MODULE,

  	.cra_u			=	{ .cipher = {
  	.cia_min_keysize	=	DES3_EDE_KEY_SIZE,
  	.cia_max_keysize	=	DES3_EDE_KEY_SIZE,

  	.cia_setkey		=	des3_ede_setkey,

  	.cia_encrypt		=	crypto_des3_ede_encrypt,
  	.cia_decrypt		=	crypto_des3_ede_decrypt } }

  } };

  static int __init des_generic_mod_init(void)

  {

  	return crypto_register_algs(des_algs, ARRAY_SIZE(des_algs));

  }

  static void __exit des_generic_mod_fini(void)

  {

  	crypto_unregister_algs(des_algs, ARRAY_SIZE(des_algs));

  }

  subsys_initcall(des_generic_mod_init);

  module_exit(des_generic_mod_fini);

  
  MODULE_LICENSE("GPL");
  MODULE_DESCRIPTION("DES & Triple DES EDE Cipher Algorithms");

  MODULE_AUTHOR("Dag Arne Osvik <da@osvik.no>");

  MODULE_ALIAS_CRYPTO("des");
  MODULE_ALIAS_CRYPTO("des-generic");
  MODULE_ALIAS_CRYPTO("des3_ede");
  MODULE_ALIAS_CRYPTO("des3_ede-generic");