[maemo-developers] New tool available to decrypt encryped N900 backups without a N900

[From: Jonathan Wilson]

Jonathan Wilson wrote:
> Thanks to Pali finding some old osso-backup source in
> http://repository.maemo.org/pool/maemo3.2/free/source/, I was able to build
> a tool that decrypts encrypted osso-backup files without the need to have a
> working N900 Fremantle install.
>
> The download is at http://www.cncmods.net/files/backupdec.zip and is
> compiled via backupdec.sh. It will compile in scratchbox if you have
> libosso-gsf-1-dev, libglib-2.0-dev and libssl-dev installed or it should
> compile in a normal linux environment if you have normal libgsf, glib and
> openssl headers installed (you will need to edit the sh file pkg-config
> options for this)
>
> To run the compiled binary, run backupdec in out password where in is the
> encrypted zip file from the backup, out is the name of the output
> unencrypted zip file and password is the password used when the zip file
> was created.
>
> It can also be used to decrypt zip files on the N900 itself if you want to
> decrypt the files without actually restoring the backup. (i.e. build an arm
> binary of this and run it on the phone)
>
> If someone has a specific need for a binary of this built for a specific
> platform, let me know and I will see what I can do to get a binary.
The source code here is released under the GPL if you want to re-use it.

Also, this only works if you know the actual password as the encryption is 
too strong to brute force it.