--- /dev/null
+/* 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.h"
+
+/**
+ 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 = cipher_descriptor[cipher].setup(key1, keylen, num_rounds, &xts->key1)) != CRYPT_OK) {
+ return err;
+ }
+ if ((err = cipher_descriptor[cipher].setup(key2, keylen, num_rounds, &xts->key2)) != CRYPT_OK) {
+ return err;
+ }
+ xts->cipher = cipher;
+
+ return err;
+}
+
+#endif
+
+/* ref: $Format:%D$ */
+/* git commit: $Format:%H$ */
+/* commit time: $Format:%ai$ */