Encrypt / Decrypt files using Carrierwave and save to S3 (Rails)

Question

I need to be able to encrypt files before saving them to S3, and then decrypt them when accessing them. Files will be images, documents, PDF, etc.

I use Carrierwave to handle loading and storing files (this is with Ruby on Rails). I store them in Amazon S3.

Has anyone done this, or have any idea how this will be achieved?

Thanks.

Answer 1

Amazon has now released features that automatically encrypt / decrypt files on S3. The need to do this by itself no longer exists. Details here http://docs.amazonwebservices.com/AmazonS3/latest/dev/index.html?UsingEncryption.html

Answer 2

To handle encryption, you should study processor implementation. If you use any other processors, you may have to look for an extension of the Carrierwave harness and the addition of a processor sequencing mechanism so you can be sure that encryption is the last.

For decryption, you can either override the existing accessor to make the decryption transparent, or add a new method that returns the decrypted file and use this instead of the accessor. The latter approach is probably more resistant to upstream changes.

Answer 3

I know this post is a few months old, but if you are still looking for answers, look at what I wrote in the carrierwave_securefile journal. It is still a newbie and probably a bit buggy on other settings, but uses Crypt19 to encrypt Blowfish in files before downloading.

http://github.com/dougc84/carrierwave_securefile