/* 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.
*/
#include "tomcrypt_private.h"
/**
@file ctr_setiv.c
CTR implementation, set IV, Tom St Denis
*/
#ifdef LTC_CTR_MODE
/**
Set an initialization vector
@param IV The initialization vector
@param len The length of the vector (in octets)
@param ctr The CTR state
@return CRYPT_OK if successful
*/
int
ctr_setiv(
const
unsigned
char
*IV, unsigned
long
len, symmetric_CTR *ctr)
{
int
err;
LTC_ARGCHK(IV != NULL);
LTC_ARGCHK(ctr != NULL);
/* bad param? */
if
((err = cipher_is_valid(ctr->cipher)) != CRYPT_OK) {
return
err;
}
if
(len != (unsigned
long
)ctr->blocklen) {
return
CRYPT_INVALID_ARG;
}
/* set IV */
XMEMCPY(ctr->ctr, IV, len);
/* force next block */
ctr->padlen = 0;
return
cipher_descriptor[ctr->cipher].ecb_encrypt(IV, ctr->pad, &ctr->key);
}
#endif
/* ref: $Format:%D$ */
/* git commit: $Format:%H$ */
/* commit time: $Format:%ai$ */