Function des_setup

extern/libtomcrypt/src/ciphers/des.c:1527–1544

Initialize the LTC_DES block cipher @param key The symmetric key you wish to pass @param keylen The key length in bytes @param num_rounds The number of rounds desired (0 for default) @param skey The key in as scheduled by this function. @return CRYPT_OK if successful */

    @return CRYPT_OK if successful
 */
int des_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey)
{
    LTC_ARGCHK(key != NULL);
    LTC_ARGCHK(skey != NULL);

    if (num_rounds != 0 && num_rounds != 16) {
        return CRYPT_INVALID_ROUNDS;
    }

    if (keylen != 8) {
        return CRYPT_INVALID_KEYSIZE;
    }

    deskey(key, EN0, skey->des.ek);
    deskey(key, DE1, skey->des.dk);

    return CRYPT_OK;
}

 /**
    Initialize the 3LTC_DES-EDE block cipher