salvage 0.1.0

Salvage distributes sensitive data to multiple people such that it can only be recovered by several people working together. This is useful for storing information with both a low risk of losing access to it and a low risk of accidental exposure. A classic application is to create a “recovery kit” for a server or infrastructure, which can be used in the event that conventionally stored keys and credentials become lost or unavailable.

Salvage works by encrypting a file or directory with a random master key and then applying a simple key-splitting scheme to distribute the key across multiple shares. You can create a kit for any number of participants with any threshold required to recover the information. For example, you might create a kit for five people, any three of which may combine their shares to recover the data.

Salvage runs under Python 2.7 or Python 3.2 and later. The only external dependency is gpg, for the cryptography. For maximum utility, it is packaged as a single flat Python script that can be run with no installation. The algorithms and file formats are simple and carefully documented to ensure that recovery is always possible even if this software is unavailable for some reason.