- one locking protocol per location: backup steps and restores hold a
shared lock, prune and untrash an exclusive one and refuse while any
run (backup, restore, export) exists; starting a backup checks and
creates the run under the exclusive lock, closing the race with prune
- snapshot entries are validated when read (relative path without '.',
'..', NUL, backslash or control characters); raw restore also checks
that the resolved directory stays below the target; the restore API
and service accept canonical paths only
- recovery kit confirmation requires a recent password confirmation and
the confirmation code printed in the current kit file (new code per
kit version), proving the kit was actually downloaded
- prune decides on the authenticated index files on the location and
refreshes the local index cache from them
- restore job marks the run failed on any error; restore runs without
progress for 6 hours are failed so they cannot block cleanup forever
- tests for safe paths and a malicious snapshot path
Dev tooling via composer (phpunit, psalm, nextcloud/ocp); vendor/ is
mounted from outside the repository by a helper script. 28 unit tests
ported from the phase-0 spikes (round trips, corruption, wrong keys,
dedup, incremental runs, partial restore, tampering, object binding,
time-boxed steps, file changed between steps).