I want to include some random (for me it is not really random 🙂) data when unlocking an UTXO.
I would like to keep the spending secured by a classic signature.
At first, I thought about using P2WPKH, but from what I understand, the witness must contain exactly two elements (the signature and the public key). If there are more, the transaction becomes invalid.
1.Am I correct?
Then I considered using a classic P2PKH, where in the scriptSig I could add my data first (e.g. a simple push of 20 bytes), before the signature and the public key.
This should preserve security, because after script execution only the top-level stack element is checked, so my extra data would not cause any issue.
2.Am I correct?
However, I also found that while this is fine from the consensus and security perspective, policy rules would prevent such a transaction from being relayed across the network since it has more than one element left on stack.
3.Am I correct?
It is very important for me to include additional data when spending funds, but I am not sure how to do this. Any ideas? Perhaps to use some other transaction type to achieve this?
Any help is welcome — even answers to only one of the above questions.
