diff --git a/common/models/LoginForm.php b/common/models/LoginForm.php
new file mode 100644
index 0000000..da6de13
--- /dev/null
+++ b/common/models/LoginForm.php
@@ -0,0 +1,90 @@
+<?php
+    namespace common\models;
+    
+    use artbox\core\models\User;
+    use Yii;
+    use yii\base\Model;
+    
+    /**
+     * Login form
+     */
+    class LoginForm extends Model
+    {
+        public $username;
+        public $password;
+        public $rememberMe = true;
+        
+        private $_user;
+        
+        /**
+         * @inheritdoc
+         */
+        public function rules()
+        {
+            return [
+                // username and password are both required
+                [
+                    [
+                        'username',
+                        'password',
+                    ],
+                    'required',
+                ],
+                // rememberMe must be a boolean value
+                [
+                    'rememberMe',
+                    'boolean',
+                ],
+                // password is validated by validatePassword()
+                [
+                    'password',
+                    'validatePassword',
+                ],
+            ];
+        }
+        
+        /**
+         * Validates the password.
+         * This method serves as the inline validation for password.
+         *
+         * @param string $attribute the attribute currently being validated
+         * @param array  $params    the additional name-value pairs given in the rule
+         */
+        public function validatePassword($attribute, $params)
+        {
+            if (!$this->hasErrors()) {
+                $user = $this->getUser();
+                if (!$user || !$user->validatePassword($this->password)) {
+                    $this->addError($attribute, 'Incorrect username or password.');
+                }
+            }
+        }
+        
+        /**
+         * Logs in a user using the provided username and password.
+         *
+         * @return bool whether the user is logged in successfully
+         */
+        public function login()
+        {
+            if ($this->validate()) {
+                return Yii::$app->user->login($this->getUser(), $this->rememberMe ? 3600 * 24 * 30 : 0);
+            } else {
+                return false;
+            }
+        }
+        
+        /**
+         * Finds user by [[username]]
+         *
+         * @return User|null
+         */
+        protected function getUser()
+        {
+            if ($this->_user === null) {
+                $this->_user = User::findByUsername($this->username);
+            }
+            
+            return $this->_user;
+        }
+    }
diff --git a/frontend/models/ContactForm.php b/frontend/models/ContactForm.php
new file mode 100644
index 0000000..d50b316
--- /dev/null
+++ b/frontend/models/ContactForm.php
@@ -0,0 +1,74 @@
+<?php
+    
+    namespace frontend\models;
+    
+    use Yii;
+    use yii\base\Model;
+    
+    /**
+     * ContactForm is the model behind the contact form.
+     */
+    class ContactForm extends Model
+    {
+        public $name;
+        public $email;
+        public $subject;
+        public $body;
+        public $verifyCode;
+        
+        /**
+         * @inheritdoc
+         */
+        public function rules()
+        {
+            return [
+                // name, email, subject and body are required
+                [
+                    [
+                        'name',
+                        'email',
+                        'subject',
+                        'body',
+                    ],
+                    'required',
+                ],
+                // email has to be a valid email address
+                [
+                    'email',
+                    'email',
+                ],
+                // verifyCode needs to be entered correctly
+                [
+                    'verifyCode',
+                    'captcha',
+                ],
+            ];
+        }
+        
+        /**
+         * @inheritdoc
+         */
+        public function attributeLabels()
+        {
+            return [
+                'verifyCode' => 'Verification Code',
+            ];
+        }
+        
+        /**
+         * Sends an email to the specified email address using the information collected by this model.
+         *
+         * @param string $email the target email address
+         *
+         * @return bool whether the email was sent
+         */
+        public function sendEmail($email)
+        {
+            return Yii::$app->mailer->compose()
+                                    ->setTo($email)
+                                    ->setFrom([ $this->email => $this->name ])
+                                    ->setSubject($this->subject)
+                                    ->setTextBody($this->body)
+                                    ->send();
+        }
+    }
diff --git a/frontend/models/PasswordResetRequestForm.php b/frontend/models/PasswordResetRequestForm.php
new file mode 100644
index 0000000..cf37a12
--- /dev/null
+++ b/frontend/models/PasswordResetRequestForm.php
@@ -0,0 +1,81 @@
+<?php
+    namespace frontend\models;
+    
+    use Yii;
+    use yii\base\Model;
+    use common\models\User;
+    
+    /**
+     * Password reset request form
+     */
+    class PasswordResetRequestForm extends Model
+    {
+        public $email;
+        
+        /**
+         * @inheritdoc
+         */
+        public function rules()
+        {
+            return [
+                [
+                    'email',
+                    'trim',
+                ],
+                [
+                    'email',
+                    'required',
+                ],
+                [
+                    'email',
+                    'email',
+                ],
+                [
+                    'email',
+                    'exist',
+                    'targetClass' => '\common\models\User',
+                    'filter'      => [ 'status' => User::STATUS_ACTIVE ],
+                    'message'     => 'There is no user with this email address.',
+                ],
+            ];
+        }
+        
+        /**
+         * Sends an email with a link, for resetting the password.
+         *
+         * @return bool whether the email was send
+         */
+        public function sendEmail()
+        {
+            /* @var $user User */
+            $user = User::findOne(
+                [
+                    'status' => User::STATUS_ACTIVE,
+                    'email'  => $this->email,
+                ]
+            );
+            
+            if (!$user) {
+                return false;
+            }
+            
+            if (!User::isPasswordResetTokenValid($user->password_reset_token)) {
+                $user->generatePasswordResetToken();
+                if (!$user->save()) {
+                    return false;
+                }
+            }
+            
+            return Yii::$app->mailer->compose(
+                    [
+                        'html' => 'passwordResetToken-html',
+                        'text' => 'passwordResetToken-text',
+                    ],
+                    [ 'user' => $user ]
+                )
+                                    ->setFrom([ Yii::$app->params[ 'supportEmail' ] => Yii::$app->name . ' robot' ])
+                                    ->setTo($this->email)
+                                    ->setSubject('Password reset for ' . Yii::$app->name)
+                                    ->send();
+        }
+    }
diff --git a/frontend/models/ResetPasswordForm.php b/frontend/models/ResetPasswordForm.php
new file mode 100644
index 0000000..5811460
--- /dev/null
+++ b/frontend/models/ResetPasswordForm.php
@@ -0,0 +1,71 @@
+<?php
+    namespace frontend\models;
+    
+    use yii\base\Model;
+    use yii\base\InvalidParamException;
+    use common\models\User;
+    
+    /**
+     * Password reset form
+     */
+    class ResetPasswordForm extends Model
+    {
+        public $password;
+        
+        /**
+         * @var \common\models\User
+         */
+        private $_user;
+        
+        /**
+         * Creates a form model given a token.
+         *
+         * @param string $token
+         * @param array  $config name-value pairs that will be used to initialize the object properties
+         *
+         * @throws \yii\base\InvalidParamException if token is empty or not valid
+         */
+        public function __construct($token, $config = [])
+        {
+            if (empty( $token ) || !is_string($token)) {
+                throw new InvalidParamException('Password reset token cannot be blank.');
+            }
+            $this->_user = User::findByPasswordResetToken($token);
+            if (!$this->_user) {
+                throw new InvalidParamException('Wrong password reset token.');
+            }
+            parent::__construct($config);
+        }
+        
+        /**
+         * @inheritdoc
+         */
+        public function rules()
+        {
+            return [
+                [
+                    'password',
+                    'required',
+                ],
+                [
+                    'password',
+                    'string',
+                    'min' => 6,
+                ],
+            ];
+        }
+        
+        /**
+         * Resets password.
+         *
+         * @return bool if password was reset.
+         */
+        public function resetPassword()
+        {
+            $user = $this->_user;
+            $user->setPassword($this->password);
+            $user->removePasswordResetToken();
+            
+            return $user->save(false);
+        }
+    }
diff --git a/frontend/models/SignupForm.php b/frontend/models/SignupForm.php
new file mode 100644
index 0000000..f7cb2e3
--- /dev/null
+++ b/frontend/models/SignupForm.php
@@ -0,0 +1,98 @@
+<?php
+    namespace frontend\models;
+    
+    use yii\base\Model;
+    use common\models\User;
+    
+    /**
+     * Signup form
+     */
+    class SignupForm extends Model
+    {
+        public $username;
+        public $email;
+        public $password;
+        
+        /**
+         * @inheritdoc
+         */
+        public function rules()
+        {
+            return [
+                [
+                    'username',
+                    'trim',
+                ],
+                [
+                    'username',
+                    'required',
+                ],
+                [
+                    'username',
+                    'unique',
+                    'targetClass' => '\common\models\User',
+                    'message'     => 'This username has already been taken.',
+                ],
+                [
+                    'username',
+                    'string',
+                    'min' => 2,
+                    'max' => 255,
+                ],
+                
+                [
+                    'email',
+                    'trim',
+                ],
+                [
+                    'email',
+                    'required',
+                ],
+                [
+                    'email',
+                    'email',
+                ],
+                [
+                    'email',
+                    'string',
+                    'max' => 255,
+                ],
+                [
+                    'email',
+                    'unique',
+                    'targetClass' => '\common\models\User',
+                    'message'     => 'This email address has already been taken.',
+                ],
+                
+                [
+                    'password',
+                    'required',
+                ],
+                [
+                    'password',
+                    'string',
+                    'min' => 6,
+                ],
+            ];
+        }
+        
+        /**
+         * Signs user up.
+         *
+         * @return User|null the saved model or null if saving fails
+         */
+        public function signup()
+        {
+            if (!$this->validate()) {
+                return null;
+            }
+            
+            $user = new User();
+            $user->username = $this->username;
+            $user->email = $this->email;
+            $user->setPassword($this->password);
+            $user->generateAuthKey();
+            
+            return $user->save() ? $user : null;
+        }
+    }
--
libgit2 0.21.4