TIL: `rename` doesn't like its source and target to be on different
partitions. This was causing the `hsmtool` tests to fail whenever we ran them
on a different partition than the lightning-dir (e.g., `/dev/shm` for faster
testing), because we made the backup copy in the current working directory.
This changes this and creates the backup next to the original file, which has
a reasonable chance to be on the same partition.
Changelog-Changed: hsmtool: The `hsmtool` now creates its backup copy in the same directory as the original `hsm_secret` file.
This, in the case of data loss on a channel with `option_static_remotekey`
negotiated, allows to likely (if the dbid is not unreasonable) recover
the funds from a remote unilateral close just with the hsm_secret.
Changelog-added: A new command, 'guesstoremote', is added to the hsmtool. It is meant to be used to recover funds after an unilateral close of a channel with `option_static_remotekey` enabled.
This takes a dbid, a "depth" (how many points to dump), the hsm_secret
path, and a potential password to dump informations about all
commitments until the depth.
Co-Authored-By: Sjors Provoost <sjors@sprovoost.nl>
Christian Decker
lisa neigut
darosior