include/crypto/des.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * DES & Triple DES EDE Cipher Algorithms.
   4  */
   5
   6 #ifndef __CRYPTO_DES_H
   7 #define __CRYPTO_DES_H
   8
   9 #include <crypto/skcipher.h>
  10 #include <linux/compiler.h>
  11 #include <linux/fips.h>
  12 #include <linux/string.h>
  13
  14 #define DES_KEY_SIZE            8
  15 #define DES_EXPKEY_WORDS        32
  16 #define DES_BLOCK_SIZE          8
  17
  18 #define DES3_EDE_KEY_SIZE       (3 * DES_KEY_SIZE)
  19 #define DES3_EDE_EXPKEY_WORDS   (3 * DES_EXPKEY_WORDS)
  20 #define DES3_EDE_BLOCK_SIZE     DES_BLOCK_SIZE
  21
  22 static inline int __des3_verify_key(u32 *flags, const u8 *key)
  23 {
  24         int err = -EINVAL;
  25         u32 K[6];
  26
  27         memcpy(K, key, DES3_EDE_KEY_SIZE);
  28
  29         if (unlikely(!((K[0] ^ K[2]) | (K[1] ^ K[3])) ||
  30                      !((K[2] ^ K[4]) | (K[3] ^ K[5]))) &&
  31                      (fips_enabled ||
  32                       (*flags & CRYPTO_TFM_REQ_FORBID_WEAK_KEYS)))
  33                 goto bad;
  34
  35         if (unlikely(!((K[0] ^ K[4]) | (K[1] ^ K[5]))) && fips_enabled)
  36                 goto bad;
  37
  38         err = 0;
  39
  40 out:
  41         memzero_explicit(K, DES3_EDE_KEY_SIZE);
  42
  43         return err;
  44
  45 bad:
  46         *flags |= CRYPTO_TFM_RES_WEAK_KEY;
  47         goto out;
  48 }
  49
  50 static inline int des3_verify_key(struct crypto_skcipher *tfm, const u8 *key)
  51 {
  52         u32 flags;
  53         int err;
  54
  55         flags = crypto_skcipher_get_flags(tfm);
  56         err = __des3_verify_key(&flags, key);
  57         crypto_skcipher_set_flags(tfm, flags);
  58         return err;
  59 }
  60
  61 extern unsigned long des_ekey(u32 *pe, const u8 *k);
  62
  63 extern int __des3_ede_setkey(u32 *expkey, u32 *flags, const u8 *key,
  64                              unsigned int keylen);
  65
  66 #endif /* __CRYPTO_DES_H */