Encryption

Encryption support is HIGHLY EXPERIMENTAL AND SUBJECT TO CHANGE. It should not be enabled for production workloads. For more details, see issue 594.

Hookshot supports end-to-bridge encryption via MSC3202. As such, encryption requires Hookshot to be connected to a homeserver that supports that MSC, such as Synapse.

Enabling encryption in Hookshot

In order for Hookshot to use encryption, it must be configured as follows:

  • The experimentalEncryption.storagePath setting must point to a directory that Hookshot has permissions to write files into. If running with Docker, this path should be within a volume (for persistency). Hookshot uses this directory for its crypto store (i.e. long-lived state relating to its encryption keys).
    • Once a crypto store has been initialized, its files must not be modified, and Hookshot cannot be configured to use another crypto store of the same type as one it has used before. If a crypto store's files get lost or corrupted, Hookshot may fail to start up, or may be unable to decrypt command messages. To fix such issues, stop Hookshot, then reset its crypto store by running yarn start:resetcrypto.
  • Redis must be enabled. Note that worker mode is not yet supported with encryption, so queue MUST NOT be configured.

If you ever reset your homeserver's state, ensure you also reset Hookshot's encryption state. This includes clearing the experimentalEncryption.storagePath directory and all worker state stored in your redis instance. Otherwise, Hookshot may fail on start up with registration errors.

Also ensure that Hookshot's appservice registration file contains every line from registration.sample.yml that appears after the If enabling encryption comment. Note that changing the registration file may require restarting the homeserver that Hookshot is connected to.

Running with Synapse

Synapse has functional support for MSC3202 as of v1.63.0. To enable it, add the following section to Synapse's configuration file (typically named homeserver.yaml):

experimental_features:
  msc3202_device_masquerading: true
  msc3202_transaction_extensions: true
  msc2409_to_device_messages_enabled: true