diff --git a/api/controllers/UserController.js b/api/controllers/UserController.js
index c8cd5437b..e8b1ecba1 100644
--- a/api/controllers/UserController.js
+++ b/api/controllers/UserController.js
@@ -4,11 +4,12 @@
  * @module :: Controller
  * @description :: Пользователи.
  */
-var passport = require('passport');
-
 var moment = require('moment');
 moment.lang('ru');
 
+var passport = require('passport'),
+	cfg = require('../../config/local');
+
 module.exports = {
 
 	profile: function (req, res) {
@@ -261,59 +262,24 @@ module.exports = {
 	},
 
 	login: function (req, res) {
-		async.waterfall([
-			function authenticate(callback) {
-				passport.authenticate('local', function (err, user, info) {
-					if (!user) {
-						if (info.message === 'Missing credentials') info.message = 'Введите логин/пароль';
-
-						return res.json({
-							error: info
-						});
-					}
-
-					callback(null, user);
-				})(req, res);
-			},
-			function logIn(user, callback) {
-				req.logIn(user, function (err) {
-					if (err) return callback(err);
-
-					callback(null, user);
-				});
-			},
-			function checkUserTable(origUser, callback) {
-				User.findOrCreate({uid: origUser.id}).exec(function (err, user) {
-					if (err) return callback(err);
-
-					if (user.prefix === undefined && user.canModerate === undefined) {
-						user.uid = origUser.id;
-						user.canModerate = [];
-						user.ugroup = 0;
-						user.startPage = '/all';
-
-						user.save(function (err) {
-							if (err) return callback(err);
-							callback(null);
-						});
-
-						return;
-					}
-
-					callback(null);
-				});
-			}
-		], function (err) {
-			if (err) throw err;
+		res.redirect(cfg.oauth2.loginURI);
+	},
 
-			if (req.body.redirectto) {
+	callback: function (req, res) {
+		passport.authenticate('oauth2', function (err, user, info) {
+			if (!user) {
 				return res.json({
-					redirectto: 'http://' + req.host + req.body.redirectto
+					error: info
 				});
 			}
-
-			res.redirect('/');
-		});
+			req.logIn(user, function (err) {
+				if (err) {
+					throw err;
+				}
+				res.redirect('/');
+				return;
+			});
+		})(req, res);
 	},
 
 	logout: function (req, res) {
diff --git a/config/local.example b/config/local.example
index cb2eb1d49..22bc0840b 100644
--- a/config/local.example
+++ b/config/local.example
@@ -47,5 +47,14 @@ module.exports = {
 			session: 0
 		}, 
 		pass:'<redis auth password>'
+	},
+	
+	oauth2: {
+		authorizationURL: 'https://api.greencubes.org/oauth/authorize',
+		tokenURL: 'https://api.greencubes.org/oauth/access_token',
+		clientID: 42,
+		clientSecret: '',
+		callbackURL: "https://help.greencubes.org/oauth/callback",
+		loginURI: 'http://api.greencubes.org/oauth/authorize?response_type=code&redirect_uri=http://help.greencubes.org/oauth/callback&client_id=42'
 	}
 };
diff --git a/config/middleware.js b/config/middleware.js
index a15348944..0d27b94f4 100644
--- a/config/middleware.js
+++ b/config/middleware.js
@@ -1,5 +1,5 @@
 var passport = require('passport');
-var LocalStrategy = require('passport-local').Strategy;
+var OAuth2Strategy = require('passport-oauth2').Strategy;
 var mysql = require('mysql');
 var crypto = require('crypto');
 var flash = require('connect-flash');
@@ -17,7 +17,7 @@ appdbconn = mysql.createPool({
 });
 
 passport.serializeUser(function (user, done) {
-	done(null, user.id);
+	done(null, user.uid);
 });
 
 passport.deserializeUser(function (id, done) {
@@ -50,6 +50,8 @@ passport.deserializeUser(function (id, done) {
 						user.startPage = '/all';
 					}
 
+					user.id = user.uid;
+
 					callback(null, user);
 				});
 		}
@@ -66,61 +68,35 @@ module.exports = {
 	// Init custom express middleware
 	express: {
 		customMiddleware: function (app) {
-			passport.use(new LocalStrategy(function (username, password, done) {
-				username = username.replace(/[^a-zA-Z0-9_-]/g, '');
-				gcdbconn.query('SELECT id, password, activation_code FROM users WHERE login = ?', [username], function (err, result) {
-					// database error
-					if (err) {
-						return done(err, false, {
-							message: 'Ошибка базы данных'
-						});
-						// username not found
-					} else if (result.length === 0) {
-						return done(null, false, {
-							message: 'Неверный логин/пароль'
-						});
-						// check password
-					} else if (result[0].activation_code === undefined) {
-						return done(null, false, {
-							message: 'Аккаунт не активирован'
+			passport.use(new OAuth2Strategy({
+				authorizationURL: cfg.oauth2.authorizationURL,
+				tokenURL: cfg.oauth2.tokenURL,
+				clientID: cfg.oauth2.clientID,
+				clientSecret: cfg.oauth2.clientSecret,
+				callbackURL: cfg.oauth2.callbackURL
+			}, function(accessToken, refreshToken, profile, done) {
+					gcdb.user.getByLogin(accessToken.username, 'gcdb', function (err, uid) {
+						User.findOrCreate({uid: uid}, function (err, user) {
+							if (!user) {
+								if (err) return done(err);
+
+								user.uid = uid;
+
+								user.group = 0; // User have group 0 by default
+								user.canModerate = [];
+								user.startPage = '/all';
+								//user.locale = 'ru';
+
+								user.save(function (err, user) {
+									return done(err, user);
+								});
+							} else {
+								return done(err, user);
+							}
 						});
-					} else {
-						var passwd = result[0].password.split('$');
-						var hash;
-						if (passwd.length == 1) {
-							hash = crypto.createHash('md5')
-								.update(password)
-								.digest('hex');
-						} else {
-							hash = crypto.createHash('sha1')
-								.update(passwd[1] + password)
-								.digest('hex');
-						}
-						// if md5 passwords match
-						if (passwd.length === 1 && passwd[0] === hash) {
-							var user = {
-								id: result[0].id,
-								username: username,
-								password: hash
-							};
-							// if sha1 passwords match
-						} else if (passwd.length !== 1 && passwd[2] === hash) {
-							var user = {
-								id: result[0].id,
-								username: username,
-								password: hash
-							};
-
-						} else {
-							return done(null, false, {
-								message: 'Неверный пароль'
-							});
-						}
-
-						done(null, user);
-					}
-				});
-			}));
+					});
+				}
+			));
 
 			app.use(passport.initialize());
 			app.use(passport.session());
@@ -129,6 +105,7 @@ module.exports = {
 
 			app.use(flash());
 
+			// Back button exceptions.
 			app.use(function (req, res, next) {
 
 				if (sails.history && ['/comments', '/csrfToken'].indexOf(req.path) === -1 && sails.history[0] !== req.url) {
@@ -144,7 +121,6 @@ module.exports = {
 				}
 
 
-
 				if (['/comments', '/csrfToken'].indexOf(req.path) === -1 && ['all', 'bugreports','rempros','bans','unbans','admreqs','user','users'].indexOf(req.path.split('/')[1]) !== -1) {
 					sails.historySpec = req.url;
 				}
diff --git a/config/policies.js b/config/policies.js
index bf72ab7e4..78c65d0f0 100644
--- a/config/policies.js
+++ b/config/policies.js
@@ -19,6 +19,7 @@ module.exports.policies = {
 		'*': ['authenticated'],
 		'loginTpl': 'notAuthenticated',
 		'login': 'notAuthenticated',
+		'callback': 'notAuthenticated',
 		'logout': true
 	},
 
diff --git a/config/routes.js b/config/routes.js
index 7b2cfce4b..7a0d3d0d0 100644
--- a/config/routes.js
+++ b/config/routes.js
@@ -24,9 +24,10 @@ module.exports.routes = {
 	'post /settings': 'user.settings',
 
 	// Вход в аккаунт и выход из него
-	'get /login': 'user.loginTpl',
-	'post /login': 'user.login',
+	'get /login': 'user.login',
+	//'post /login': 'user.login',
 	'/logout': 'user.logout',
+	'/oauth/callback': 'user.callback',
 
 	// Оповещения
 	'get /notifs': 'notif.listNotifications',
diff --git a/package.json b/package.json
index 2821db53f..9553f7013 100644
--- a/package.json
+++ b/package.json
@@ -11,6 +11,7 @@
     "optimist": "0.3.4",
     "passport": "~0.1.17",
     "passport-local": "~0.1.6",
+    "passport-oauth2": "1.1.x",
     "connect-redis": "1.4.x",
     "connect-flash": "0.1.x",
     "mysql": "2.0.0-alpha9",
diff --git a/views/home/partials/header.ejs b/views/home/partials/header.ejs
index 4c52669f3..58b6a57c0 100644
--- a/views/home/partials/header.ejs
+++ b/views/home/partials/header.ejs
@@ -4,8 +4,8 @@
 		<a href="https://greencubes.org/?action=recover#t" class="item">
 			Забыли пароль?
 		</a>
-		<a href="//greencubes.org/?action=start" class="item">
-			Регистрация <i class="user icon"></i>
+		<a href="/login" class="item">
+			Войти через аккаунт GC <i class="user icon"></i>
 		</a>
 	</div>
 </div>
diff --git a/views/home/preview.ejs b/views/home/preview.ejs
index 63c1f2be2..eb499fa43 100644
--- a/views/home/preview.ejs
+++ b/views/home/preview.ejs
@@ -26,27 +26,6 @@
 								<h3>Решаем проблемы, одобряем заявки</h3>
 							</div>
 						</div>
-						<div class="right floated two wide column loginform">
-							<form id="loginform" style="margin-top:50px">
-								<div class="ui form" style="display: inline-block !important">
-									<div class="field">
-										<div class="ui left labeled icon input">
-											<input placeholder="Имя пользователя" type="text" name="username">
-											<i class="user icon"></i>
-										</div>
-									</div>
-									<div class="field">
-										<div class="ui left labeled icon input">
-											<input placeholder="Пароль" type="password" name="password">
-											<i class="lock icon"></i>
-										</div>
-									</div>
-									<button type="submit" class="ui blue submit button gc-center">Войти</button>
-								</div>
-								<input type="hidden" name="_csrf" value="<%= _csrf %>" />
-							</form>
-							<div id="loginerr"></div>
-						</div>
 					</div>
 				</div>
 				<div class="second section">