Commission contract on BSV (3)

Before , We introduced two ways to entrust bitcoin ： One is in Script level , The other is Transaction level .

We generalize the former to delegate to any script / Intelligent contract , Not just the public key . It allows a person to authorize any smart contract to spend a person's bitcoin .

The full code is shown below ：

contract DelegateToScript {
    
    PubKey owner;

    public function delegate(Sig ownerSig, bytes delegatedScript, PubKey derivedPubKey, PubKey X, int lambda, SigHashPreimage txPreimage) {
    
        require(Tx.checkPreimage(txPreimage));
        
        // ensure delegated script is signed by the owner
        require(Oracle.verifyData(delegatedScript, ownerSig, this.owner, derivedPubKey, X, lambda, txPreimage));

        // use delegated script as the new locking script, while maintaining value
        bytes output = Utils.buildOutput(delegatedScript, SigHash.value(txPreimage));
        require(hash256(output) == SigHash.hashOutputs(txPreimage));
    }
}

DelegateToScript Contract source code

The first 9 Line to check if the delegate script is signed and therefore by the owner to grant authorization . The first 12 Xing He 13 Line usage OP_PUSH_TX Ensure that the delegate script enters the output of the expense transaction as a new lock script , Be similar to Pay to Script Hash (P2SH) The simulation .