calculateChallengeResponse method
Implementation
Future<String> calculateChallengeResponse(String base64Challenge) async {
final challengeString = utf8.decode(base64.decode(base64Challenge));
final challenge = parseKeyValue(challengeString);
final clientFinalMessageBare = 'c=biws,r=${challenge['r']!}';
final saltedPassword = await calculateSaltedPassword(
challenge['s']!,
int.parse(challenge['i']!),
);
final clientKey = await calculateClientKey(saltedPassword);
final storedKey = (await _hash.hash(clientKey)).bytes;
final authMessage =
'$initialMessageNoGS2,$challengeString,$clientFinalMessageBare';
final clientSignature =
await calculateClientSignature(authMessage, storedKey);
final clientProof = calculateClientProof(clientKey, clientSignature);
final serverKey = await calculateServerKey(saltedPassword);
_serverSignature =
base64.encode(await calculateServerSignature(authMessage, serverKey));
return '$clientFinalMessageBare,p=${base64.encode(clientProof)}';
}