Cross channel Splice testing #8363
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few things need updating, otherwise lgtm!
Make the failure reason more clear by adding more information to the signature failure message.
We used to use a check on the active psbt to see if our splice signature was in it — but now we need to generate the signature early. So we have to add a field tracking if we’ve sent it and add it to the database, wire protocols, and inflight objects.
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Use the new i_sent_sigs field to track if we’ve sent our peer our user sigs.
Previous behavior was to fail on abort when we have signatures in the inflight — change this behavior to fail on abort if we have sent our peer our signatures.
When doing a multi channel splice, we need to break the deadlock by signing the shared output early (even though it is not sent to the peer until later).
Add more information to funding issue failure messages when splicing
Adding verbose logging option to introspect into what interactive tx is doing with inputs.
When doing a cross channel splice, inputs move from having no SIGHASH to having SIGHASH_ALL assigned. This causes psbt_get_changeset to flag the input as having changed, as the sighash value is compared. This causes the second channel splice to `tx_remove_input` the input as it doesn’t match anymore, breaking the splice. We fix this by removing the sighash value from input comparisions.
Since the signature data may vary, we must copy the new psbt into splicing->current_psbt. This never occured during normal operation, but when doing a cross splice there may be vital signature(s) in the psbt that came from another splice that get dropped without this step.
A python test that splices into two channels at the same time with on transaction. Changelog-Added: Adding support for cross-channel splicing.
Counting remote inputs needing sigs can be in its own method
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Doing trivial squash rebase now... |
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Implemented a test for a splice-in into two channels at the same time using one transaction.
The test revealed three issues:
interactive-txdiffs a9d1dbfThis PR fixes those issues, adds a pytest for them, and makes basic two channel splices work, lets goooo 🔥