How to use Dropbox with Truecrypt?

I have some files that need to be accessible from multiple computers, but encrypted on each computer. Something like the 'shared folder' feature on Dropbox, but with the folder encrypted locally on each computer.

What I'm looking for:

• A folder shared between multiple computers running Vista or Mac OS X
• This folder is encrypted of each of the computers
• The unencrypted files are accessible when logging in to the Dropbox homepage.

Basically, I guess I am looking to encrypt the Dropbox folder on each of the computers, but only having Dropbox syncing the unencrypted content.

Is this possible? And please ask if the above is unclear.

Cheers!

Solution 1:

I'd guess that if any TrueCrypt or OS X encrypted folder is accessible before Dropbox starts (maybe Dropbox will even keep trying if access fails initially), then Dropbox might very well be oblivious about the fact that its local storage is actually encrypted?

Then all there's to do: set up an encrypted folder, and then make Dropbox use that folder. The latter is simply a preference (on a Mac: "Dropbox Folder Location").

(On a Mac, such folder will not be backed up by Time Machine until you log off. But as Dropbox is keeping revisions as well, I guess that can be used as a backup.)

Solution 2:

Edit to add: This does not allow for file access through the website. /Edit

Here's what I do:

1. Create a TrueCrypt container volume file and put it in your dropbox folder.
2. Have TrueCrypt.exe accessible on each compute (could be in your DropBox folder as well).
3. When you need to access it, mount the file as a drive on the hosted computer.

Several things to know:

• DropBox will not update the file until TrueCrypt has dismounted it.
• if you end up mounting it at two locations, DropBox will call them "conflicting versions" and you'll need to resolve their differences. (When I've done this, I mount both files at the same time and diff them using BeyondCompare3.)
• The fact that DropBox save historical versions of the container file could theoretically compromise the encryption (though I can't back that up with a citation right now).

Solution 3:

http://wiki.dropbox.com/TipsAndTricks/IncreasePrivacyAndSafety