Skip to main content

Sighash Module

Calculate signature hashes for transaction signing.

Overview​

The sighash.mo module calculates signature hashes for both Schnorr and ECDSA signatures.

Sighash Types​

import Sighash "mo:hoosat-mo/sighash";

Sighash.SigHashAll                 // 0x01
Sighash.SigHashNone                // 0x02
Sighash.SigHashSingle              // 0x04
Sighash.SigHashAnyOneCanPay        // 0x80
Sighash.SigHashAll_AnyOneCanPay    // 0x81
Sighash.SigHashNone_AnyOneCanPay   // 0x82
Sighash.SigHashSingle_AnyOneCanPay // 0x84

Key Functions​

calculateSighashSchnorr​

Calculate Schnorr sighash for a transaction input.

public func calculateSighashSchnorr(
  tx: HoosatTransaction,
  inputIndex: Nat,
  utxo: UTXO,
  hashType: SigHashType,
  reusedValues: SighashReusedValues
) : ?[Nat8]

calculateSighashEcdsa​

Calculate ECDSA sighash for a transaction input.

public func calculateSighashEcdsa(
  tx: HoosatTransaction,
  inputIndex: Nat,
  utxo: UTXO,
  hashType: SigHashType,
  reusedValues: SighashReusedValues
) : ?[Nat8]

Reused Values​

For efficiency when signing multiple inputs:

let reusedValues : Sighash.SighashReusedValues = {
  var previousOutputsHash = null;
  var sequencesHash = null;
  var sigOpCountsHash = null;
  var outputsHash = null;
  var payloadHash = null;
};

for (i in inputs.keys()) {
  let hash = Sighash.calculateSighashEcdsa(
    tx, i, utxos[i],
    Sighash.SigHashAll,
    reusedValues
  );
};