public KeygenDerivedkeys GenerateKey(byte[] baseSeed)
{
byte[] preparedSeed = new byte[DrbgCtx.NFC3D_DRBG_MAX_SEED_SIZE];
var preparedSeedSize = PrepareSeed(baseSeed, preparedSeed);
return(DrbgCtx.GenerateBytes(this.hmacKey, preparedSeed, preparedSeedSize));
}
public static KeygenDerivedkeys GenerateBytes(byte[] hmacKey, byte[] seed, int seedSize)
{
int offset = 0;
int outputSize = 16 * 3;
byte[] temp = new byte[NFC3D_DRBG_OUTPUT_SIZE];
byte[] output = new byte[outputSize];
DrbgCtx rngCtx = new DrbgCtx(hmacKey, seed, seedSize);
while (outputSize > 0)
{
if (outputSize < NFC3D_DRBG_OUTPUT_SIZE)
{
rngCtx.Step(temp, 0);
Array.Copy(temp, 0, output, offset, outputSize);
break;
}
rngCtx.Step(output, offset);
offset += NFC3D_DRBG_OUTPUT_SIZE;
outputSize -= NFC3D_DRBG_OUTPUT_SIZE;
}
var outkeys = new KeygenDerivedkeys
{
aesKey = new byte[16],
aesIV = new byte[16],
hmacKey = new byte[16]
};
Array.Copy(output, 0, outkeys.aesKey, 0, outkeys.aesKey.Length);
Array.Copy(output, 16, outkeys.aesIV, 0, outkeys.aesIV.Length);
Array.Copy(output, 32, outkeys.hmacKey, 0, outkeys.hmacKey.Length);
return(outkeys);
}