Merge pull request #185 from indexzero/crypto

[wip] Allow for "secure" option to be passed to `nconf.stores.File`

.gitignore

@@ -5,6 +5,7 @@ test/fixtures/*.json
 !test/fixtures/malformed.json
 !test/fixtures/bom.json
 !test/fixtures/no-bom.json
+!test/fixtures/secure.json
 node_modules/
 node_modules/*
 npm-debug.log

.travis.yml

@@ -1,14 +1,28 @@
-language: node_js
 sudo: false
-before_install:
-  - '[ "${TRAVIS_NODE_VERSION}" != "0.8" ] || npm install -g npm@1.4.28'
-  - npm install -g npm@latest
+language: node_js
 node_js:
   - "0.8"
   - "0.10"
-  - "0.11"
   - "0.12"
-  - "iojs"
+  - "4.1"
+
+before_install:
+  - '[ "${TRAVIS_NODE_VERSION}" != "0.8" ] || travis_retry npm install -g npm@1.4.28'
+  - '[ "${TRAVIS_NODE_VERSION}" == "0.8" ] || travis_retry npm install -g npm@2.14.2'
+  - travis_retry npm install
+
+before_install:
+  - travis_retry npm install -g npm@2.5.1
+  - travis_retry npm install
+
+script:
+  - npm test
+
+matrix:
+  allow_failures:
+    - node_js: "0.8"
+    - node_js: "0.10"
+
 notifications:
   email:
     - travis@nodejitsu.com

README.md

@@ -216,7 +216,9 @@ Loads a given object literal into the configuration hierarchy. Both `nconf.defau
 ```
 
 ### File
-Based on the Memory store, but provides additional methods `.save()` and `.load()` which allow you to read your configuration to and from file. As with the Memory store, all method calls are synchronous with the exception of `.save()` and `.load()` which take callback functions. It is important to note that setting keys in the File engine will not be persisted to disk until a call to `.save()` is made. Note a custom key must be supplied as the first parameter for hierarchy to work if multiple files are used.
+Based on the Memory store, but provides additional methods `.save()` and `.load()` which allow you to read your configuration to and from file. As with the Memory store, all method calls are synchronous with the exception of `.save()` and `.load()` which take callback functions.
+
+It is important to note that setting keys in the File engine will not be persisted to disk until a call to `.save()` is made. Note a custom key must be supplied as the first parameter for hierarchy to work if multiple files are used.
 
 ``` js
   nconf.file('path/to/your/config.json');
@@ -229,6 +231,35 @@ The file store is also extensible for multiple file formats, defaulting to `JSON
 
 If the file does not exist at the provided path, the store will simply be empty.
 
+#### Encrypting file contents
+
+As of `nconf@0.8.0` it is now possible to encrypt and decrypt file contents using the `secure` option:
+
+``` js
+nconf.file('secure-file', {
+  file: 'path/to/secure-file.json',
+  secure: {
+    secret: 'super-secretzzz-keyzz',
+    alg: 'aes-256-ctr'
+  }
+})
+```
+
+This will encrypt each key using [`crypto.createCipher`](https://nodejs.org/api/crypto.html#crypto_crypto_createcipher_algorithm_password), defaulting to `aes-256-ctr`. The encrypted file contents will look like this:
+
+```
+{
+  "config-key-name": {
+    "alg": "aes-256-ctr", // cipher used
+    "value": "af07fbcf"   // encrypted contents
+  },
+  "another-config-key": {
+    "alg": "aes-256-ctr",   // cipher used
+    "value": "e310f6d94f13" // encrypted contents
+  },
+}
+```
+
 ### Redis
 There is a separate Redis-based store available through [nconf-redis][0]. To install and use this store simply:
 
@@ -252,22 +283,8 @@ Once installing both `nconf` and `nconf-redis`, you must require both modules to
 ```
 
 ## Installation
-
-### Installing npm (node package manager)
 ```
-  curl http://npmjs.org/install.sh | sh
-```
-
-### Installing nconf
-```
-  [sudo] npm install nconf
-```
-
-## More Documentation
-There is more documentation available through docco. I haven't gotten around to making a gh-pages branch so in the meantime if you clone the repository you can view the docs:
-
-```
-  open docs/nconf.html
+  npm install nconf --save
 ```
 
 ## Run Tests

lib/nconf.js

@@ -8,8 +8,12 @@
 var fs = require('fs'),
     async = require('async'),
     common = require('./nconf/common'),
-    Provider = require('./nconf/provider').Provider,
-    nconf = module.exports = new Provider();
+    Provider = require('./nconf/provider').Provider;
+
+//
+// `nconf` is by default an instance of `nconf.Provider`.
+//
+var nconf = module.exports = new Provider();
 
 //
 // Expose the version from the package.json

lib/nconf/stores/file.js

@@ -5,7 +5,8 @@
  *
  */
 
-var fs = require('fs'),
+var crypto = require('crypto'),
+    fs = require('fs'),
     path = require('path'),
     util = require('util'),
     formats = require('../formats'),
@@ -30,7 +31,25 @@ var File = exports.File = function (options) {
   this.file    = options.file;
   this.dir     = options.dir    || process.cwd();
   this.format  = options.format || formats.json;
-  this.json_spacing = options.json_spacing || 2;
+  this.secure  = options.secure;
+  this.spacing = options.json_spacing
+    || options.spacing
+    || 2;
+
+  if (this.secure) {
+    this.secure = typeof this.secure === 'string'
+      ? { secret: this.secure }
+      : this.secure;
+
+    this.secure.alg = this.secure.alg || 'aes-256-ctr';
+    if (this.secure.secretPath) {
+      this.secret = fs.readFileSync(this.secure.secretPath, 'utf8');
+    }
+
+    if (!this.secure.secret) {
+      throw new Error('secure.secret option is required');
+    }
+  }
 
   if (options.search) {
     this.search(this.dir);
@@ -53,9 +72,7 @@ File.prototype.save = function (value, callback) {
     value = null;
   }
 
-  fs.writeFile(this.file, this.format.stringify(this.store, null, this.json_spacing), function (err) {
-    return err ? callback(err) : callback();
-  });
+  fs.writeFile(this.file, this.stringify(), callback);
 };
 
 //
@@ -66,12 +83,7 @@ File.prototype.save = function (value, callback) {
 // using the format specified by `this.format` synchronously.
 //
 File.prototype.saveSync = function (value) {
-  try {
-    fs.writeFileSync(this.file, this.format.stringify(this.store, null, this.json_spacing));
-  }
-  catch (ex) {
-    throw(ex);
-  }
+  fs.writeFileSync(this.file, this.stringify());
   return this.store;
 };
 
@@ -97,12 +109,13 @@ File.prototype.load = function (callback) {
       }
 
       try {
-        //deals with string that include BOM
+        // Deals with string that include BOM
         var stringData = data.toString();
+        if (stringData.charAt(0) === '\uFEFF') {
+          stringData = stringData.substr(1);
+        }
 
-        if (stringData.charAt(0) === '\uFEFF') stringData = stringData.substr(1);
-        self.store = self.format.parse(stringData);
-
+        self.store = self.parse(stringData);
       }
       catch (ex) {
         return callback(new Error("Error parsing your configuration file: [" + self.file + ']: ' + ex.message));
@@ -119,30 +132,81 @@ File.prototype.load = function (callback) {
 // and responds appropriately.
 //
 File.prototype.loadSync = function () {
-  var data, self = this;
-
-  if (!existsSync(self.file)) {
-    self.store = {};
-    data = {};
+  if (!existsSync(this.file)) {
+    this.store = {};
+    return this.store;
   }
-  else {
+
   //
   // Else, the path exists, read it from disk
   //
   try {
-      //deals with file that include BOM
+    // Deals with file that include BOM
     var fileData = fs.readFileSync(this.file, 'utf8');
-      if (fileData.charAt(0) === '\uFEFF') fileData = fileData.substr(1);
+    if (fileData.charAt(0) === '\uFEFF') {
+      fileData = fileData.substr(1);
+    }
 
-      data = this.format.parse(fileData);
-      this.store = data;
+    this.store = this.parse(fileData);
   }
   catch (ex) {
-      throw new Error("Error parsing your configuration file: [" + self.file + ']: ' + ex.message);
-    }
+    throw new Error("Error parsing your configuration file: [" + this.file + ']: ' + ex.message);
   }
 
-  return data;
+  return this.store;
+};
+
+//
+// ### function stringify ()
+// Returns an encrypted version of the contents IIF
+// `this.secure` is enabled
+//
+File.prototype.stringify = function () {
+  var data = this.store,
+      self = this;
+
+  if (this.secure) {
+    data = Object.keys(data).reduce(function (acc, key) {
+      var value = self.format.stringify(data[key]);
+      acc[key] = {
+        alg: self.secure.alg,
+        value: cipherConvert(value, {
+          alg: self.secure.alg,
+          secret: self.secure.secret,
+          encs: { input: 'utf8', output: 'hex' }
+        })
+      }
+
+      return acc;
+    }, {});
+  }
+
+  return this.format.stringify(data, null, this.spacing);
+};
+
+//
+// ### function parse (contents)
+// Returns a decrypted version of the contents IFF
+// `this.secure` is enabled.
+//
+File.prototype.parse = function (contents) {
+  var parsed = this.format.parse(contents),
+      self = this;
+
+  if (!this.secure) {
+    return parsed;
+  }
+
+  return Object.keys(parsed).reduce(function (acc, key) {
+    var decrypted = cipherConvert(parsed[key].value, {
+      alg: parsed[key].alg || self.secure.alg,
+      secret: self.secure.secret,
+      encs: { input: 'hex', output: 'utf8' }
+    });
+
+    acc[key] = self.format.parse(decrypted);
+    return acc;
+  }, {});
 };
 
 //
@@ -235,3 +299,15 @@ File.prototype.search = function (base) {
 
   return fullpath;
 };
+
+//
+// ### function cipherConvert (contents, opts)
+// Returns the result of the cipher operation
+// on the contents contents.
+//
+function cipherConvert(contents, opts) {
+  var encs = opts.encs;
+  var cipher = crypto.createCipher(opts.alg, opts.secret);
+  return cipher.update(contents, encs.input, encs.output)
+    + cipher.final(encs.output);
+}

test/fixtures/secure.json

@@ -0,0 +1,18 @@
+{
+  "isNull": {
+    "alg": "aes-256-ctr",
+    "value": "af07fbcf"
+  },
+  "literal": {
+    "alg": "aes-256-ctr",
+    "value": "e310f6d94f13"
+  },
+  "arr": {
+    "alg": "aes-256-ctr",
+    "value": "9a78b783175e69bb8f3458042b1c098d8ed9613410fac185b3735099224f8fe4ece0f0da8decfddbbf0eab3b7c391c47772b5441"
+  },
+  "obj": {
+    "alg": "aes-256-ctr",
+    "value": "ba78b783175968add93a680429424ae4cf957d2916ebcfa399730bb17200ddb0ecacb183c1b1ebcd950ced76726964062e74643c995c47372bfb1311bee8f65bbeb5a1d9426537a6d83635220ec7934e1d7cc187f7218cd4afadfa2f107fb42c232d80d95c160ee704fa8e922998b0b3e47ec579dd0baef7cae6d7dbaa203d732adb5cff22b80d810d7191237999cd8dc528d8f2201ae128a9f9e2df96d1a816aa73e3e6b8e6246cd98b454e453b36f43f9117cb4af8fa85429a92"
+  }
+}

test/stores/file-store-test.js

@@ -222,5 +222,40 @@ vows.describe('nconf/stores/file').addBatch({
       }
     }
   }
+}).addBatch({
+  "When using the nconf file store": {
+    topic: function () {
+      var secureStore = new nconf.File({
+        file: path.join(__dirname, '..', 'fixtures', 'secure.json'),
+        secure: 'super-secretzzz'
+      });
+
+      secureStore.store = data;
+      return secureStore;
+    },
+    "the stringify() method should encrypt properly": function (store) {
+      var contents = JSON.parse(store.stringify());
+      Object.keys(data).forEach(function (key) {
+        assert.isObject(contents[key]);
+        assert.isString(contents[key].value);
+        assert.equal(contents[key].alg, 'aes-256-ctr');
+      });
+    },
+    "the parse() method should decrypt properly": function (store) {
+      var contents = store.stringify();
+      var parsed = store.parse(contents);
+      assert.deepEqual(parsed, data);
+    },
+    "the load() method should decrypt properly": function (store) {
+      store.load(function (err, loaded) {
+        assert.isNull(err);
+        assert.deepEqual(loaded, data);
+      });
+    },
+    "the loadSync() method should decrypt properly": function (store) {
+      var loaded = store.loadSync()
+      assert.deepEqual(loaded, data);
+    }
+  }
 }).export(module);