Author: Jeremy 2022-01-17 05:55:00
Published on: 2022-01-17T05:55:00+00:00
A proposal has been made to extend the PSBT standard by adding new fields for pay-to-contract key tweaking data. P2C tweaks are used to create a cryptographic commitment to some message using elliptic curve properties. In order to spend an output containing a P2C commitment, the same commitment should be added to the corresponding private key. The proposed PSBT input field for inputs spending UTXOs with previously created P2C public key tweaks will allow signers to produce valid signatures. The proposal abstracts details of specific P2C protocols and provides a universal method for spending previous outputs containing P2C tweaks. The new per-input type is defined as including 33 bytes of compact public key serialization specifying to which of keys the P2C tweak may be applied, and the 32 byte value which must be added to a private key to produce correct ECDSA and/or Schnorr signature ("key tweak"). The proposal is compatible with existing consensus rules and does not require any modifications. It provides sufficient information for creating valid signatures for spending different output types containing tweaked public keys. The proposal only addresses spending of transaction outputs containing P2C tweaks and not construction of new P2C commitments or transactions containing them in their outputs.
Updated on: 2023-06-15T15:15:08.057553+00:00