Private key encryption

README.md

@@ -61,11 +61,13 @@ Where
 
 Use `createPrivateKey` for creating private keys
 
-    pem.createPrivateKey(keyBitsize, callback)
+    pem.createPrivateKey(keyBitsize, [options,] callback)
 
 Where
 
   * **keyBitsize** is an optional size of the key, defaults to 2048 (bit)
+  * **options** is an optional object of the cipher and password (both required for encryption), defaults {cipher:'',password:''} 
+  (ciphers:["aes128", "aes192", "aes256", "camellia128", "camellia192", "camellia256", "des", "des3", "idea"])
   * **callback** is a callback function with an error object and `{key}`
 
 ### Create a Certificate Signing Request

lib/pem.js

@@ -26,23 +26,43 @@ module.exports.config = config;
  * Creates a private key
  *
  * @param {Number} [keyBitsize=2048] Size of the key, defaults to 2048bit
+ * @param {Object} [options] object of cipher and password {cipher:'aes128',password:'xxx'}, defaults empty object
  * @param {Function} callback Callback function with an error object and {key}
  */
-function createPrivateKey(keyBitsize, callback) {
-    if (!callback && typeof keyBitsize === 'function') {
+function createPrivateKey(keyBitsize, options, callback) {
+    var fpath;
+    if (!callback && !options && typeof keyBitsize === 'function') {
         callback = keyBitsize;
         keyBitsize = undefined;
+        options = {};
+    }
+    else if (!callback && keyBitsize && typeof options === 'function') {
+        callback = options;
+        options = {};
     }
 
     keyBitsize = Number(keyBitsize) || 2048;
 
     var params = ['genrsa',
         '-rand',
-        '/var/log/mail:/var/log/messages',
-        keyBitsize
+        '/var/log/mail:/var/log/messages'
     ];
-
+    var cipher = ["aes128", "aes192", "aes256", "camellia128", "camellia192", "camellia256", "des", "des3", "idea"];
+
+    if (options && options.cipher && ( -1 !== Number(cipher.indexOf(options.cipher)) ) && options.password){
+        fpath = pathlib.join(tempDir, crypto.randomBytes(20).toString('hex'));
+        fs.writeFileSync(fpath, options.password);
+        params.push( '-' + options.cipher );
+        params.push( '-passout' );
+        params.push( 'file:' + fpath );
+    }
+
+    params.push(keyBitsize);
+
     execOpenSSL(params, 'RSA PRIVATE KEY', function(error, key) {
+        if(fpath) {
+            fs.unlink(fpath);
+        }
         if (error) {
             return callback(error);
         }

test/pem.js

@@ -63,6 +63,20 @@ exports['General Tests'] = {
         });
     },
 
+    'Create 2048bit Private key with Password': function(test) {
+        pem.createPrivateKey(2048,{cipher:'des',password:'TestMe'}, function(error, data) {
+            var key = (data && data.key || '').toString();
+            test.ifError(error);
+            test.ok(key);
+            test.ok(key.match(/ENCRYPTED\n/));
+            test.ok(key.match(/^\n*\-\-\-\-\-BEGIN RSA PRIVATE KEY\-\-\-\-\-\n/));
+            test.ok(key.match(/\n\-\-\-\-\-END RSA PRIVATE KEY\-\-\-\-\-\n*$/));
+            test.ok(key.trim().length > 1700 && key.trim().length < 1780);
+            test.ok(fs.readdirSync('./tmp').length === 0);
+            test.done();
+        });
+    },
+
     'Create default CSR': function(test) {
         pem.createCSR(function(error, data) {
             var csr = (data && data.csr || '').toString();