crypto Namespace Reference

wilton/crypto
Cryptography operations. More...

Functions
Object	createCryptKey (String secret, Function|Undefined callback)
	Create crypt params from the specified string.
Undefined	decryptFile (Object options, Function|Undefined callback)
	AES decryption.
Undefined	encryptFile (Object options, Function|Undefined callback)
	AES encryption.
String	hashFile (Object options, Function|Undefined callback)
	Compute SHA256 sum of a file.

Detailed Description

This module provides access to cryptography operations: encryption and hash sum computation. Processing is done on files without loading all their content into memory.

Usage example:

// compute SHA-256 from file contents
var sha256 = crypto.hashFile({
  filePath: plain
});

// create encryption key and init vector
// from arbitrary secret string
var pars = crypto.createCryptKey("mysecret");

// encrypt file
crypto.encryptFile({
    filePath: "path/to/plain.txt",
    destFilePath: "path/to/encrypted.dat",
    cryptKey: pars.cryptKey,
    initVec: pars.initVec
});

// decrypt file
crypto.decryptFile({
    filePath: "path/to/encrypted.dat",
    destFilePath: "path/to/decrypted.txt",
    cryptKey: pars.cryptKey,
    initVec: pars.initVec
});

Function Documentation

Object crypto::createCryptKey	(	String	secret,
		Function|Undefined	callback
	)

Deterministically creates encryption key and initialization vector from the specified input string.

Parameters

secret	String input secret string to create crypt params
callback	Function|Undefined callback to receive result or error

Returns

Object with the following fields:

• cryptKey String encryption key in hexadecimal
• initVec String initialization vector in hexadecimal

Undefined crypto::decryptFile	(	Object	options,
		Function|Undefined	callback
	)

Decrypts specified file using AES with specifief encryption key and initialization vector.

Key an IV may be created with createCryptKey.

Results are written to the specified destination path.

Parameters

options	Object configuration object, see possible options below
callback	Function|Undefined callback to receive result or error

Returns

Undefined

Options

• filePath String path to the file to decrypt
• desfilePath String path to the file to write decryption results into
• cryptKey String encryption key in hexadecimal, must be 32 bytes long
• initVec String init vector in hexadecimal, must be 16 bytes long

Undefined crypto::encryptFile	(	Object	options,
		Function|Undefined	callback
	)

Encrypts specified file using AES with specifief encryption key and initialization vector.

Key an IV may be created with createCryptKey.

Results are written to the specified destination path.

Parameters

options	Object configuration object, see possible options below
callback	Function|Undefined callback to receive result or error

Returns

Undefined

Options

• filePath String path to the file to encrypt
• desfilePath String path to the file to write encryption results into
• cryptKey String encryption key in hexadecimal, must be 32 bytes long
• initVec String init vector in hexadecimal, must be 16 bytes long

String crypto::hashFile	(	Object	options,
		Function|Undefined	callback
	)

Computes SHA256 hash sum from the contents of a specified file. Hash sum value returned as a hexadecimal string.

Parameters

options	Object configuration object, see possible options below
callback	Function|Undefined callback to receive result or error

Returns

String

Options

• filePath String path to the file to compute SHA256