Add support to reverse encryption

[neurodroid]

From salatiel...@gmail.com on August 24, 2012 11:18:47

Please add support to use reverse encryption in criptonite. In encfs reverse mode (encfs --reverse) you can have an unencrypted local folder and a mount point that encrypts the files on the fly. So we can make backups to dropbox encrypted while keeping the local data unencrypted removing any overhead to access the files locally.

Example:

/sdcard/DCIM -> unencrypted encfs --reverse /sdcard/DCIM /sdcard/dropbox_sync_pics /sdcard/dropbox_sync _pics -> on the fly encrypted that will be synced with dropbox using third part apps. So i can work locally with no overhead at all and only during sync my files will be transparently encrypted on dropbox servers.

Thanks !

Original issue: http://code.google.com/p/cryptonite/issues/detail?id=39

[neurodroid]

From christoph.schmidthieber@gmail.com on August 25, 2012 06:14:57

Labels: -Type-Defect Type-Enhancement

[neurodroid]

From oer...@gmail.com on November 01, 2012 07:47:41

I want this SO much. I hate that my pics are unencrypted on dropbox. Please add. It should be very easy to implement.

[dimovnike]

I would like this too. Please, make an option to start reverse encryption at boot with a saved obfuscated password.

[pepa65]

This is a prime use of encfs, and it's built-in! Such an easy solution in a cloud-storage world!! Want this for sure.

[dimovnike]

the problem is that the --reverse option itself works good from cmdline, the encfs can be started with a script from cmdline via some autostart app but the mounted dir is not seen by apps.... now if someone can find a good solution to this :)

[neurodroid]

@dimovnike I think it's an SELinux issue, as pointed out in issue #47 and issue #83. If someone could send a pull request addressing these issues (@xmikos seems to have some experience) I'd be grateful.

[dimovnike]

Im more inclined to think its mount namespace issue, I am researching this, will get back when I have some results.

[dimovnike]

The new SuperSU has the option to join the master mount namespace. So while having last SuperSU the following command works:

su --mount-master -d -c "/data/data/csh.cryptonite/encfs --public --reverse --extpass='echo -n scrambled==|base64 -d' /storage/sdcard0/DCIM /storage/sdcard0/path/path/"

I got "Transport endpoint is not connected" a couple of times (i suspect the encfs dies, but why?). I can see the encrypted files from any app.

here is more info about master mount name space https://plus.google.com/+Chainfire/posts/hLKytCwUm6k

Also the transport endpoint error occured again.

[neurodroid]

If we can find out how SuperSU achieves this, maybe we can port that functionality to Cryptonite?

[dimovnike]

yeah, im sure there is a way, but the problem now is how to avoid "Transport endpoint is not connected" errors. Do you think android kills encfs because its not run as as service?