Rsyncrypto

From WikiIndex
Jump to: navigation, search
lingnu_banner_logo.png
Rsyncrypto -
Rsync Friendly File Encryption

Recent changes • [No WikiNode] • [No About] • [No Mobile URL]
Founded by: Shachar Shemesh
Status: Dormant
Language: English
Edit mode: LoginToEdit
Wiki engine: MediaWiki
Wiki license: Creative Commons Attribution Share Alike
Main topic: Software
Wiki size: unknown size see stats
wikiFactor: 1 info / verify

(Page count as of: 20YY-MM-DD
wikiFactor as of: 2012-MM-DD)


The Rsyncrypto wiki is a place to discuss Rsyncrypto and related tools and techniques. This Rsyncrypto wiki was founded June 2008, and powered by MediaWiki, but in 2019, the wiki was recreated using the same original URL, but all edit history, and nigh-on all content was lost.

Why is Rsyncrypto

Sometimes it is necessary to store files on a remote server. This is typically needed for backup purposes. When that is done, there are two concerns that need to be addressed, ideally, you want to both:

  1. How to keep the privacy of the files stored?
  2. How to keep bandwidth usage to a minimum?

Both problems have rather simple solutions:

  1. Encrypt the files prior to sending them, keep the key locally.
  2. Use rsync to only transfer the changes.

There is just one problem: the two solutions contradict. Plain mode encryption of files hide the specific changes to the file, making rsync useless at detecting in-file changes. This is where rsyncrypto comes to the rescue.

What is Rsyncrypto

Rsyncrypto is a modified encryption scheme. It is based on industry standard Advanced Encryption Standard (AES) for symmetric encryption, as well as RSA (Rivest–Shamir–Adleman) for having different keys for each file while allowing a single key to decrypt all files. It even uses an encryption mode that is based on cipher block chaining (CBC).

Rsyncrypto does, however, do one thing differently. It changes the encryption schema from plain CBC to a slightly modified version. This modification ensures that two almost identical files, such as the same file before an after a change, when encrypted using Rsyncrypto and the same key, will produce almost identical encrypted files. This means that both objectives can be achieved simultaneously.

Awards

Rsyncrypto won first prize in the 2007 edition free software trophy competition (Trophées du Libre) in the security category.

Tutorial

There are some tutorials on line, which might help you with your experience with rsyncrypto:

More resources
Related wiki
External links