text: /* SPDX-License-Identifier: GPL-2.0 */
  /* 
   * DES & Triple DES EDE Cipher Algorithms.
   */
  
  #ifndef __CRYPTO_DES_H
  #define __CRYPTO_DES_H
  
  #include <linux/types.h>
  
  #define DES_KEY_SIZE		8
  #define DES_EXPKEY_WORDS	32
  #define DES_BLOCK_SIZE		8
  
  #define DES3_EDE_KEY_SIZE	(3 * DES_KEY_SIZE)
  #define DES3_EDE_EXPKEY_WORDS	(3 * DES_EXPKEY_WORDS)
  #define DES3_EDE_BLOCK_SIZE	DES_BLOCK_SIZE
  
  struct des_ctx {
  	u32 expkey[DES_EXPKEY_WORDS];
  };
  
  struct des3_ede_ctx {
  	u32 expkey[DES3_EDE_EXPKEY_WORDS];
  };
  
  void des_encrypt(const struct des_ctx *ctx, u8 *dst, const u8 *src);
  void des_decrypt(const struct des_ctx *ctx, u8 *dst, const u8 *src);
  
  void des3_ede_encrypt(const struct des3_ede_ctx *dctx, u8 *dst, const u8 *src);
  void des3_ede_decrypt(const struct des3_ede_ctx *dctx, u8 *dst, const u8 *src);
  
  /**
   * des_expand_key - Expand a DES input key into a key schedule
   * @ctx: the key schedule
   * @key: buffer containing the input key
   * @len: size of the buffer contents
   *
   * Returns 0 on success, -EINVAL if the input key is rejected and -ENOKEY if
   * the key is accepted but has been found to be weak.
   */
  int des_expand_key(struct des_ctx *ctx, const u8 *key, unsigned int keylen);
  
  /**
   * des3_ede_expand_key - Expand a triple DES input key into a key schedule
   * @ctx: the key schedule
   * @key: buffer containing the input key
   * @len: size of the buffer contents
   *
   * Returns 0 on success, -EINVAL if the input key is rejected and -ENOKEY if
   * the key is accepted but has been found to be weak. Note that weak keys will
   * be rejected (and -EINVAL will be returned) when running in FIPS mode.
   */
  int des3_ede_expand_key(struct des3_ede_ctx *ctx, const u8 *key,
  			unsigned int keylen);
  
  #endif /* __CRYPTO_DES_H */
  