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data-lite-c/Sources/DataLiteC/libtomcrypt/modes/xts/xts_init.c
2025-10-24 19:33:21 +03:00

58 lines
1.5 KiB
C

/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
#include "tomcrypt_private.h"
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wconversion"
#pragma clang diagnostic ignored "-Wshorten-64-to-32"
/**
Source donated by Elliptic Semiconductor Inc (www.ellipticsemi.com) to the LibTom Projects
*/
#ifdef LTC_XTS_MODE
/** Start XTS mode
@param cipher The index of the cipher to use
@param key1 The encrypt key
@param key2 The tweak encrypt key
@param keylen The length of the keys (each) in octets
@param num_rounds The number of rounds for the cipher (0 == default)
@param xts [out] XTS structure
Returns CRYPT_OK upon success.
*/
int xts_start(int cipher, const unsigned char *key1, const unsigned char *key2, unsigned long keylen, int num_rounds,
symmetric_xts *xts)
{
int err;
/* check inputs */
LTC_ARGCHK(key1 != NULL);
LTC_ARGCHK(key2 != NULL);
LTC_ARGCHK(xts != NULL);
/* check if valid */
if ((err = cipher_is_valid(cipher)) != CRYPT_OK) {
return err;
}
if (cipher_descriptor[cipher].block_length != 16) {
return CRYPT_INVALID_ARG;
}
/* schedule the two ciphers */
if ((err = ecb_start(cipher, key1, keylen, num_rounds, &xts->key1)) != CRYPT_OK) {
return err;
}
if ((err = ecb_start(cipher, key2, keylen, num_rounds, &xts->key2)) != CRYPT_OK) {
return err;
}
xts->cipher = cipher;
return err;
}
#endif
#pragma clang diagnostic pop