ComputeInputScript generates a complete InputIndex for the passed transaction with the signature as defined within the passed SignDescriptor. This method should be capable of generating the proper input script for both regular p2wkh/p2tr outputs and p2wkh outputs nested within a regular p2sh output. Note that when using this method to sign inputs belonging to the wallet, the only items of the SignDescriptor that need to be populated are pkScript in the TxOut field, the value in that same field, and finally the input index.

DeriveSharedKey returns a shared secret key by performing Diffie-Hellman key derivation between the ephemeral public key in the request and the node's key specified in the key_desc parameter. Either a key locator or a raw public key is expected in the key_desc, if neither is supplied, defaults to the node's identity private key: P_shared = privKeyNode * ephemeralPubkey The resulting shared public key is serialized in the compressed format and hashed with sha256, resulting in the final key length of 256bit.

MuSig2Cleanup (experimental!) allows a caller to clean up a session early in cases where it's obvious that the signing session won't succeed and the resources can be released. NOTE: The MuSig2 BIP is not final yet and therefore this API must be considered to be HIGHLY EXPERIMENTAL and subject to change in upcoming releases. Backward compatibility is not guaranteed!

MuSig2CombineKeys (experimental!) is a stateless helper RPC that can be used to calculate the combined MuSig2 public key from a list of all participating signers' public keys. This RPC is completely stateless and deterministic and does not create any signing session. It can be used to determine the Taproot public key that should be put in an on-chain output once all public keys are known. A signing session is only needed later when that output should be _spent_ again. NOTE: The MuSig2 BIP is not final yet and therefore this API must be considered to be HIGHLY EXPERIMENTAL and subject to change in upcoming releases. Backward compatibility is not guaranteed!

MuSig2CombineSig (experimental!) combines the given partial signature(s) with the local one, if it already exists. Once a partial signature of all participants is registered, the final signature will be combined and returned. NOTE: The MuSig2 BIP is not final yet and therefore this API must be considered to be HIGHLY EXPERIMENTAL and subject to change in upcoming releases. Backward compatibility is not guaranteed!

MuSig2CreateSession (experimental!) creates a new MuSig2 signing session using the local key identified by the key locator. The complete list of all public keys of all signing parties must be provided, including the public key of the local signing key. If nonces of other parties are already known, they can be submitted as well to reduce the number of RPC calls necessary later on. NOTE: The MuSig2 BIP is not final yet and therefore this API must be considered to be HIGHLY EXPERIMENTAL and subject to change in upcoming releases. Backward compatibility is not guaranteed!

MuSig2RegisterNonces (experimental!) registers one or more public nonces of other signing participants for a session identified by its ID. This RPC can be called multiple times until all nonces are registered. NOTE: The MuSig2 BIP is not final yet and therefore this API must be considered to be HIGHLY EXPERIMENTAL and subject to change in upcoming releases. Backward compatibility is not guaranteed!

MuSig2Sign (experimental!) creates a partial signature using the local signing key that was specified when the session was created. This can only be called when all public nonces of all participants are known and have been registered with the session. If this node isn't responsible for combining all the partial signatures, then the cleanup flag should be set, indicating that the session can be removed from memory once the signature was produced. NOTE: The MuSig2 BIP is not final yet and therefore this API must be considered to be HIGHLY EXPERIMENTAL and subject to change in upcoming releases. Backward compatibility is not guaranteed!

SignMessage signs a message with the key specified in the key locator. The returned signature is fixed-size LN wire format encoded. The main difference to SignMessage in the main RPC is that a specific key is used to sign the message instead of the node identity private key.

SignOutputRaw is a method that can be used to generated a signature for a set of inputs/outputs to a transaction. Each request specifies details concerning how the outputs should be signed, which keys they should be signed with, and also any optional tweaks. The return value is a fixed 64-byte signature (the same format as we use on the wire in Lightning). If we are unable to sign using the specified keys, then an error will be returned.

VerifyMessage verifies a signature over a message using the public key provided. The signature must be fixed-size LN wire format encoded. The main difference to VerifyMessage in the main RPC is that the public key used to sign the message does not have to be a node known to the network.