#5032 "Plugin install takes its URL and checksum from the catalog, requires
the checksum, and extracts only inside the plugin folder". The install form
carried the download URL and checksum as hidden fields, so any admin POST
could make Steward fetch and import code from anywhere, unchecked, and a zip
member like ../x.py was written wherever it pointed.
- The route takes only the plugin name and reads download_url and
checksum_sha256 from the configured catalogs; a name no repository lists
is refused. Installs are audited (plugin.install / plugin.install_failed).
- The checksum is required; the name must be a plain identifier.
- extract_plugin refuses any member that resolves outside the plugin
folder, caps the download at 50 MB and the unpacked size at 200 MB.
- The zip unpacks into a staging folder and is swapped in whole: a refused
or failed install leaves the installed copy untouched, and an update no
longer leaves the old version's deleted files behind.
- The catalog shows "Can't install: the catalog lists no checksum" in place
of the button for an entry without one.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
