I was thinking about similar tool to this one and this was the biggest obstacle I could think of. Also write touch and create a file for each keystroke.
To become something more than a hack you have a few choices:
- a blacklist - will never be enough, still arguments may be problematic
- a whitelist - will always be not enough, arguments may be problematic, but a bit less than with a blacklist
- limiting permissions somehow - tricky
The last and best option IMHO would be to wrap it in a sandbox, where all filesystem access is behind an overlay (i.e. mount namespaces and overlayfs). This way if you are satisfied you can apply changes (if there is anything to change). The overlay would be removed and created on each keypress. It may be also possible to wrap process access, so one could safely play with kill, but I'm not sure. Even network settings to some extent. But there is nothing you can do with curl -X POST or something similar.
To become something more than a hack you have a few choices:
- a blacklist - will never be enough, still arguments may be problematic
- a whitelist - will always be not enough, arguments may be problematic, but a bit less than with a blacklist
- limiting permissions somehow - tricky
The last and best option IMHO would be to wrap it in a sandbox, where all filesystem access is behind an overlay (i.e. mount namespaces and overlayfs). This way if you are satisfied you can apply changes (if there is anything to change). The overlay would be removed and created on each keypress. It may be also possible to wrap process access, so one could safely play with kill, but I'm not sure. Even network settings to some extent. But there is nothing you can do with curl -X POST or something similar.