Decrypt encrypted ssh private keys

var decrypt = require('ssh-key-decrypt');

// you have to actually know this already of course.
var passphrase = 'hoohah';

var fs = require('fs');
var path = require('path');

var keyfile = path.resolve(process.env.HOME, '.ssh', 'id_rsa');
var fileData = fs.readFileSync(keyfile, 'ascii');

var key = decrypt(fileData, passphrase);

// now key is the decoded data as a buffer
// You can also optionally pass in an output encoding

var b64Key = decrypt(fileData, passphrase, 'base64');

Data can be either a string or a buffer. It is the contents of the key file.

If the file is not encrypted, then the passphrase doesn't matter.

If the file is encrypted, then it'll decrypt it.

Either way, the data is returned in the output encoding specified.

This module is synchronous, as it performs no I/O. However, it can potentially be kind of slow, since it does a bunch of crypto and hashes, so do not call it often or in hot code paths.

Also, as this is crypto, and thus only either exactly right or extremely wrong, it throws if anything unexpected is encountered.

• des3, aka DES-EDE3-CBC
• des, aka DES-CBC
• aes128, aka AES-128-CBC
• aes192, aka AES-192-CBC
• aes256, aka AES-256-CBC

The cipher type is determined from the file. You do not have to specify this.