This commit improves TLV decoding safety and consistency across multiple
packages by enforcing fixed-length requirements and adding unit tests to
prevent malformed TLV records from being accepted.
Changes include:
- lnwire:
* Enforce 8-byte length in Fee TLV decoder.
* Enforce PubNonceSize in Musig2Nonce TLV decoder.
* Enforce 8-byte length in ShortChannelID TLV decoder.
* Added roundtrip and invalid length tests for Fee, Musig2Nonce,
and ShortChannelID records.
- routing/route:
* Enforce Vertex TLV length (33 bytes).
* Added encode/decode and invalid length tests for Vertex.
- tlv:
* Enforce correct length in DBytes33 decoder (33 bytes).
* Added tests ensuring all fixed-size primitive decoders reject
incorrect TLV lengths.
By strictly validating TLV lengths, we prevent malformed or corrupted
TLV records from being silently accepted, improving protocol safety.
In this commit, we update new Taproot related TLVs (nonces, partial sig,
sig with nonce, etc). Along the way we were able to get rid of some
boiler plate, but most importantly, we're able to better protect against
API misuse (using a nonce that isn't initialized, etc) with the new
options API. In some areas this introduces a bit of extra boiler plate,
and where applicable I used some new helper functions to help cut down
on the noise.
Note to reviewers: this is done as a single commit, as changing the API
breaks all callers, so if we want things to compile it needs to be in a
wumbo commit.
Erick Cestari