Rsyncrypto

Rsyncrypto is a modified encryption scheme. It is based on industry standard AES for symmetric encryption, as well as RSA 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 CBC.

Rsyncrypto does, however, do one thing differently. It will modify the encryption schema from plain CBC to a slightly changed 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.