/* 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, tomstdenis@gmail.com, http://libtomcrypt.com */#include "tomcrypt.h"/**   @file cbc_start.c   CBC implementation, start chain, Tom St Denis*/#ifdef LTC_CBC_MODE/**   Initialize a CBC context   @param cipher      The index of the cipher desired   @param IV          The initial vector   @param key         The secret key    @param keylen      The length of the secret key (octets)   @param num_rounds  Number of rounds in the cipher desired (0 for default)   @param cbc         The CBC state to initialize   @return CRYPT_OK if successful*/int cbc_start(int cipher, const unsigned char *IV, const unsigned char *key,               int keylen, int num_rounds, symmetric_CBC *cbc){   int x, err;    LTC_ARGCHK(IV != NULL);   LTC_ARGCHK(key != NULL);   LTC_ARGCHK(cbc != NULL);   /* bad param? */   if ((err = cipher_is_valid(cipher)) != CRYPT_OK) {      return err;   }   /* setup cipher */   if ((err = cipher_descriptor[cipher].setup(key, keylen, num_rounds, &cbc->key)) != CRYPT_OK) {      return err;   }   /* copy IV */   cbc->blocklen = cipher_descriptor[cipher].block_length;   cbc->cipher   = cipher;   for (x = 0; x < cbc->blocklen; x++) {       cbc->IV[x] = IV[x];   }   return CRYPT_OK;}#endif/* $Source: /cvs/libtom/libtomcrypt/src/modes/cbc/cbc_start.c,v $ *//* $Revision: 1.5 $ *//* $Date: 2006/06/29 01:46:46 $ */