vault-cipher

Provides a high-level authenticated encryption API that Vault uses to encrypt its stored settings. On Node, it's backed by the crypto module, while in the browser it uses crypto-js. Random values are generated with crypto.randomBytes() or crypto.getRandomValues() where available.

The encryption algorithm is an encrypt-then-MAC scheme based on AES and HMAC.

The given secret is used to derive an encryption key and a signing key using PBKDF2
The plaintext is padded to a multiple of the AES block size using PKCS#7
A random iv is selected using crypto.randomBytes()
The plaintext is encrypted using AES-256-CBC with the encryption key and iv to produce ciphertext
iv and ciphertext are concatenated and signed using HMAC-SHA-256 with the signing key to produce mac
The result is the concatenation of iv, ciphertext and mac

+--------+      +--------+      +----------------+----------------+
| secret |----->| PBKDF2 |----->| encryption key |  signing key   |
+--------+      +--------+      +----------------+----------------+
                                    |                     |
+---------+                         V                     |
| message |------------------>+-------------+             |
+---------+     +----+        | AES-256-CBC |             |
                | iv |------->+-------------+             |
                +----+              |                     |
                   |                |                     |
                   V                V                     V
              +----------+------------------+     +--------------+
              |    iv    |    ciphertext    |---->| HMAC-SHA-256 |
              +----------+------------------+     +--------------+
                      |               |                 |
                      V               V                 V
                  +----------+------------------+-----------+
                  |    iv    |    ciphertext    |    mac    |
                  +----------+------------------+-----------+

Its high-level API provides a simple way to encrypt and decrypt text:

var Cipher = require('vault-cipher'),
    cipher = new Cipher('your secret key');

var ciphertext = cipher.encrypt('some text');

cipher.decrypt(ciphertext) // -> 'some text'

Settings

The cipher is configurable by passing options to the constructor, for example:

var cipher = new Cipher('secret key', {format: 'hex', work: 1000})

The available options are:

format: the output format of the ciphertext, either base64 (default) or hex
salt: a salt string used during PBKDF2 key derivation, defaults to a GUID embedded in the library
work: the number of PBKDF2 iterations used to derive the encryption and signing keys, default is 1000

License

(The MIT License)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

jimmywilk/vault-cipher

vault-cipher

Settings

License