project idea: portable password safe

Werner Almesberger werner at
Wed Sep 11 11:52:59 EDT 2013

EdorFaus wrote:
> Or, alternately, the device could behave as if the write lock was
> off, except that all reads/writes goes to a separate jailed section

Kinda like the journal in a journaling file system ? Yes, that
could be a possibility: collect all changes, then present the
user with a "diff" and ask whether to "commit".

Not sure if that would be convenient with a relatively small
display, though.

I'd envision basically the following USB protocols:

- plain HID
- feedback over HID (via "features"):
  - select account entry
  - password store management
- USB storage:
  - read-only mode (access to the ecrypted memory card; that would
    give you a slow (Full Speed only)  but "trusted" reader)
  - read-write mode
- DFU to the internal Flash (for development)

Not sure whether regular firmware upgrades should also be allowed
via DFU. In any case, they could come from the memory card.

- Werner

More information about the discussion mailing list