2006-01-26 18:11:56 +00:00
|
|
|
/* 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.
|
|
|
|
|
*
|
2007-07-20 17:48:02 +00:00
|
|
|
* Tom St Denis, tomstdenis@gmail.com, http://libtom.org
|
2006-01-26 18:11:56 +00:00
|
|
|
*/
|
|
|
|
|
#include "tomcrypt.h"
|
|
|
|
|
|
|
|
|
|
/**
|
|
|
|
|
@file lrw_setiv.c
|
|
|
|
|
LRW_MODE implementation, Set the current IV, Tom St Denis
|
|
|
|
|
*/
|
|
|
|
|
|
2006-08-30 23:30:00 +00:00
|
|
|
#ifdef LTC_LRW_MODE
|
2006-01-26 18:11:56 +00:00
|
|
|
|
|
|
|
|
/**
|
|
|
|
|
Set the IV for LRW
|
|
|
|
|
@param IV The IV, must be 16 octets
|
|
|
|
|
@param len Length ... must be 16 :-)
|
|
|
|
|
@param lrw The LRW state to update
|
|
|
|
|
@return CRYPT_OK if successful
|
|
|
|
|
*/
|
|
|
|
|
int lrw_setiv(const unsigned char *IV, unsigned long len, symmetric_LRW *lrw)
|
|
|
|
|
{
|
|
|
|
|
int err;
|
|
|
|
|
#ifdef LRW_TABLES
|
|
|
|
|
unsigned char T[16];
|
|
|
|
|
int x, y;
|
|
|
|
|
#endif
|
|
|
|
|
LTC_ARGCHK(IV != NULL);
|
|
|
|
|
LTC_ARGCHK(lrw != NULL);
|
|
|
|
|
|
|
|
|
|
if (len != 16) {
|
|
|
|
|
return CRYPT_INVALID_ARG;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if ((err = cipher_is_valid(lrw->cipher)) != CRYPT_OK) {
|
|
|
|
|
return err;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* copy the IV */
|
|
|
|
|
XMEMCPY(lrw->IV, IV, 16);
|
|
|
|
|
|
|
|
|
|
/* check if we have to actually do work */
|
|
|
|
|
if (cipher_descriptor[lrw->cipher].accel_lrw_encrypt != NULL && cipher_descriptor[lrw->cipher].accel_lrw_decrypt != NULL) {
|
|
|
|
|
/* we have accelerators, let's bail since they don't use lrw->pad anyways */
|
|
|
|
|
return CRYPT_OK;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
#ifdef LRW_TABLES
|
|
|
|
|
XMEMCPY(T, &lrw->PC[0][IV[0]][0], 16);
|
|
|
|
|
for (x = 1; x < 16; x++) {
|
|
|
|
|
#ifdef LTC_FAST
|
|
|
|
|
for (y = 0; y < 16; y += sizeof(LTC_FAST_TYPE)) {
|
|
|
|
|
*((LTC_FAST_TYPE *)(T + y)) ^= *((LTC_FAST_TYPE *)(&lrw->PC[x][IV[x]][y]));
|
|
|
|
|
}
|
|
|
|
|
#else
|
|
|
|
|
for (y = 0; y < 16; y++) {
|
|
|
|
|
T[y] ^= lrw->PC[x][IV[x]][y];
|
|
|
|
|
}
|
|
|
|
|
#endif
|
|
|
|
|
}
|
|
|
|
|
XMEMCPY(lrw->pad, T, 16);
|
|
|
|
|
#else
|
|
|
|
|
gcm_gf_mult(lrw->tweak, IV, lrw->pad);
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
return CRYPT_OK;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
#endif
|
|
|
|
|
/* $Source$ */
|
|
|
|
|
/* $Revision$ */
|
|
|
|
|
/* $Date$ */
|
