/// <summary>
/// Get the 'sender' of a transaction.
/// </summary>
/// <param name="tx"></param>
/// <param name="coinView"></param>
/// <param name="blockTxs"></param>
/// <returns></returns>
public static GetSenderResult GetSender(Transaction tx, CoinView coinView, IList <Transaction> blockTxs)
{
OutPoint prevOut = tx.Inputs[0].PrevOut;
// Check the txes in this block first
if (blockTxs != null && blockTxs.Count > 0)
{
foreach (Transaction btx in blockTxs)
{
if (btx.GetHash() == prevOut.Hash)
{
Script script = btx.Outputs[prevOut.N].ScriptPubKey;
return(GetAddressFromScript(script));
}
}
}
// Check the utxoset for the p2pk of the unspent output for this transaction
if (coinView != null)
{
FetchCoinsResponse fetchCoinResult = coinView.FetchCoinsAsync(new uint256[] { prevOut.Hash }).Result;
UnspentOutputs unspentOutputs = fetchCoinResult.UnspentOutputs.FirstOrDefault();
if (unspentOutputs == null)
{
throw new Exception("Unspent outputs to smart contract transaction are not present in coinview");
}
Script script = unspentOutputs.Outputs[prevOut.N].ScriptPubKey;
return(GetAddressFromScript(script));
}
return(GetSenderResult.CreateFailure("Unable to get the sender of the transaction"));
}
/// <inheritdoc />
public GetSenderResult GetSender(Transaction tx, ICoinView coinView, IList <Transaction> blockTxs)
{
OutPoint prevOut = tx.Inputs[0].PrevOut;
// Check the txes in this block first
if (blockTxs != null && blockTxs.Count > 0)
{
foreach (Transaction btx in blockTxs)
{
if (btx.GetHash() == prevOut.Hash)
{
if (prevOut.N >= btx.Outputs.Count)
{
return(GetSenderResult.CreateFailure(InvalidOutputIndex));
}
Script script = btx.Outputs[prevOut.N].ScriptPubKey;
return(this.GetAddressFromScript(script));
}
}
}
// Check the utxoset for the p2pk of the unspent output for this transaction
if (coinView != null)
{
FetchCoinsResponse fetchCoinResult = coinView.FetchCoins(new OutPoint[] { prevOut });
// The result from the coinview should never be null, so we do not check for that condition here.
// It will simply not contain the requested outputs in the dictionary if they did not exist in the coindb.
if (fetchCoinResult.UnspentOutputs.All(o => o.Key != prevOut))
{
return(GetSenderResult.CreateFailure(OutputsNotInCoinView));
}
UnspentOutput unspentOutputs = fetchCoinResult.UnspentOutputs.First(o => o.Key == prevOut).Value;
// Since we now fetch a specific UTXO from the coindb instead of an entire transaction, it is no longer meaningful to check
// (for the coindb at least - block transactions are handled separately above) whether the prevOut index is within bounds.
// So that check has been removed from here and we proceed directly to checking spent-ness.
if (unspentOutputs.Coins == null)
{
return(GetSenderResult.CreateFailure(OutputAlreadySpent));
}
TxOut senderOutput = unspentOutputs.Coins.TxOut;
return(this.GetAddressFromScript(senderOutput.ScriptPubKey));
}
return(GetSenderResult.CreateFailure(UnableToGetSender));
}
/// <inheritdoc />
public GetSenderResult GetSender(Transaction tx, ICoinView coinView, IList <Transaction> blockTxs)
{
OutPoint prevOut = tx.Inputs[0].PrevOut;
// Check the txes in this block first
if (blockTxs != null && blockTxs.Count > 0)
{
foreach (Transaction btx in blockTxs)
{
if (btx.GetHash() == prevOut.Hash)
{
if (prevOut.N >= btx.Outputs.Count)
{
return(GetSenderResult.CreateFailure(InvalidOutputIndex));
}
Script script = btx.Outputs[prevOut.N].ScriptPubKey;
return(this.GetAddressFromScript(script));
}
}
}
// Check the utxoset for the p2pk of the unspent output for this transaction
if (coinView != null)
{
FetchCoinsResponse fetchCoinResult = coinView.FetchCoinsAsync(new uint256[] { prevOut.Hash }).Result;
UnspentOutputs unspentOutputs = fetchCoinResult.UnspentOutputs.FirstOrDefault();
if (unspentOutputs == null)
{
return(GetSenderResult.CreateFailure(OutputsNotInCoinView));
}
if (prevOut.N >= unspentOutputs.Outputs.Length)
{
return(GetSenderResult.CreateFailure(InvalidOutputIndex));
}
TxOut senderOutput = unspentOutputs.Outputs[prevOut.N];
if (senderOutput == null)
{
return(GetSenderResult.CreateFailure(OutputAlreadySpent));
}
return(this.GetAddressFromScript(senderOutput.ScriptPubKey));
}
return(GetSenderResult.CreateFailure(UnableToGetSender));
}
/// <summary>
/// Get the address from a P2PK or a P2PKH
/// </summary>
/// <param name="script"></param>
/// <returns></returns>
public static GetSenderResult GetAddressFromScript(Script script)
{
PubKey payToPubKey = PayToPubkeyTemplate.Instance.ExtractScriptPubKeyParameters(script);
if (payToPubKey != null)
{
var address = new uint160(payToPubKey.Hash.ToBytes());
return(GetSenderResult.CreateSuccess(address));
}
if (PayToPubkeyHashTemplate.Instance.CheckScriptPubKey(script))
{
var address = new uint160(PayToPubkeyHashTemplate.Instance.ExtractScriptPubKeyParameters(script).ToBytes());
return(GetSenderResult.CreateSuccess(address));
}
return(GetSenderResult.CreateFailure("Addresses can only be retrieved from Pay to Pub Key or Pay to Pub Key Hash"));
}