63 lines
1.5 KiB
C
63 lines
1.5 KiB
C
|
/* 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://libtom.org
|
||
|
|
*/
|
||
|
|
#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
|
||
|
|
|
||
|
|
/* $Source$ */
|
||
|
|
/* $Revision$ */
|
||
|
|
/* $Date$ */
|