ecb_decrypt.c

来自「这是一个用来加解密的算法库」· C语言 代码 · 共 47 行

/* LibTomCrypt, modular cryptographic library -- Tom St Denis
 *
 * LibTomCrypt is a library that provides various cryptographic
 * algorithms in a highly modular and flexible manner.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 *
 * Tom St Denis, [e-mail], http://libtomcrypt.org
 */
#include "tomcrypt.h"

/**
  @file ecb_decrypt.c
  ECB implementation, decrypt block, Tom St Denis
*/

#ifdef ECB

/**
   ECB decrypt
   @param ct      Ciphertext
   @param pt      [out] Plaintext
   @param ecb     ECB state
   @return CRYPT_OK if successful
*/
int ecb_decrypt(const unsigned char *ct, unsigned char *pt, symmetric_ECB *ecb)
{
   int err;
   LTC_ARGCHK(pt != NULL);
   LTC_ARGCHK(ct != NULL);
   LTC_ARGCHK(ecb != NULL);

   /* valid cipher? */
   if ((err = cipher_is_valid(ecb->cipher)) != CRYPT_OK) {
       return err;
   }
   LTC_ARGCHK(cipher_descriptor[ecb->cipher].ecb_decrypt != NULL);
   
   cipher_descriptor[ecb->cipher].ecb_decrypt(ct, pt, &ecb->key);
   return CRYPT_OK;
}

#endif