/// Creates a new Did power up request for the given [pairwiseDid] and of the given [amount].
/// Signs everything that needs to be signed (i.e. the signature JSON inside the payload) with the
/// private key contained inside the given [senderWallet] and the [privateKey].
public static async Task <TransactionResult> requestDidPowerUp(
Wallet senderWallet,
String pairwiseDid,
List <StdCoin> amount,
RSAPrivateKey privateKey,
StdFee fee = null,
BroadcastingMode mode = BroadcastingMode.SYNC
)
{
RequestDidPowerUp requestDidPowerUp = await RequestDidPowerUpHelper.fromWallet(
senderWallet,
pairwiseDid,
amount,
privateKey
);
MsgRequestDidPowerUp msg = new MsgRequestDidPowerUp(requestDidPowerUp: requestDidPowerUp);
// Careful here, Eugene: we are passing a list of BaseType containing the derived MsgSetDidDocument msg
return(await TxHelper.createSignAndSendTx(new List <StdMsg> {
msg
}, senderWallet, fee : fee, mode : mode));
}
public static async Task <RequestDidPowerUp> fromWallet(Wallet senderWallet, String pairwiseDid, List <StdCoin> amount, RSAPrivateKey privateKey)
{
// Get the timestamp
String timestamp = GenericUtils.getTimeStampEpoch(); // RC 20200913: Be careful, the Dart version uses a different timestamp format non ISO-8601 - Why?
String senderDid = senderWallet.bech32Address;
// Build and sign the signature
byte[] signedSignatureHash = SignHelper.signPowerUpSignature(
senderDid: senderDid,
pairwiseDid: pairwiseDid,
timestamp: timestamp,
rsaPrivateKey: privateKey);
// Build the payload -*
DidPowerUpRequestPayload payload = new DidPowerUpRequestPayload(
senderDid: senderDid,
pairwiseDid: pairwiseDid,
timeStamp: timestamp,
signature: Convert.ToBase64String(signedSignatureHash)
);
// =============
// Encrypt proof
// =============
// Generate an AES-256 key
KeyParameter aesKey = KeysHelper.generateAesKey(); // await ?
// Encrypt the payload
byte[] encryptedProof = EncryptionHelper.encryptStringWithAesGCM(JsonConvert.SerializeObject(payload), aesKey);
// =================
// Encrypt proof key
// =================
// Encrypt the key using the Tumbler public RSA key
RSAPublicKey rsaPubTkKey = await EncryptionHelper.getGovernmentRsaPubKey(senderWallet.networkInfo.lcdUrl);
byte[] encryptedProofKey = EncryptionHelper.encryptBytesWithRsa(aesKey.GetKey(), rsaPubTkKey);
// Build the message
RequestDidPowerUp request = new RequestDidPowerUp(
claimantDid: senderDid,
amount: amount,
powerUpProof: Convert.ToBase64String(encryptedProof),
uuid: Guid.NewGuid().ToString(),
encryptionKey: Convert.ToBase64String(encryptedProofKey)
);
return(request);
}
/// Takes [senderDid], [pairwiseDid], [timestamp] and:
/// 1. Concatenate senderDid, pairwiseDid and timestamp as payload
/// 2. Returns the RSA PKCS1v15 (the SHA256 digest is calculated inside the
/// signer) and sign using the [rsaPrivateKey]
public static byte[] signPowerUpSignature(String senderDid, String pairwiseDid, String timestamp, RSAPrivateKey rsaPrivateKey)
{
String concat = senderDid + pairwiseDid + timestamp;
ISigner sig = SignerUtilities.GetSigner("SHA256WithRSA");
// Populate key
sig.Init(true, rsaPrivateKey.secretKey);
// Get the bytes to be signed from the string
byte[] buffer = Encoding.UTF8.GetBytes(concat);
// Calc the signature
sig.BlockUpdate(buffer, 0, buffer.Length);
byte[] signature = sig.GenerateSignature();
return(signature);
}