diff --git a/roundcube-defense.php b/roundcube-defense.php
new file mode 100644
index 0000000..2125abc
--- /dev/null
+++ b/roundcube-defense.php
@@ -0,0 +1,116 @@
+<?php
+/*
+ *  This file is part of the Roundcube plugin: roundcube-defense.
+ *
+ *  @author Steve Allison <roundcube-defense@nooblet.org>
+ *
+ *  roundcube-defense is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  roundcube-defense is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with roundcube-defense.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+class roundcube-defense extends rcube_plugin {
+    
+    // Roundcube parent class
+    private $rc;
+    
+    // Config variables
+    private $whitelist, $blacklist, $fail_max,
+        $fail_reset, $ban_period, $repeat_multiplier,
+        $repeat_reset, $db_table, $db_expire, $log_pwd;
+    
+    // Remote client IP address
+    private $ipaddr;
+    
+  /**
+    * Check if IP is matched against all IPs in array,
+    * including CIDR matches
+    *
+    * @param string ip address
+    * @param array ip/cidr addresses to match against
+    * @return bool
+    */
+    private isIPinArray($ip, $array) {
+        foreach ($array as $value) {
+            if (strpos($value, '/') === false) && ($ip == $value) { return true; }
+            if (isIPinCIDR($ip, $value)) { return true; }
+        }
+        return false;
+    }
+  /**
+    * Check if IP is within stated CIDR address
+    *
+    * @param string ip address
+    * @param string cidr address
+    * @return bool
+    */
+    private isIPinCIDR($ip, $cidr) {
+        list($subnet, $mask) = explode('/', $cidr);
+        return ((ip2long($ip) & ~((1 << (32 - $mask)) - 1) ) == ip2long($subnet));
+    }
+    
+  /**
+    * Contructor, initialization
+    *
+    */
+    public function init() {
+    
+        // create parent class
+        $this->rc = rcube::get_instance();
+        
+        // load configuration
+        $this->load_config();
+        
+        // set config variables
+        $this->whitelist = $this->rc->config->get('defense_whitelist', array('127.0.0.1'));
+        $this->blacklist = $this->rc->config->get('defense_blacklist', array());
+        $this->fail_max = $this->rc->config->get('fail_max', 5);
+        $this->fail_reset = $this->rc->config->get('fail_reset', 600);
+        $this->ban_period = $this->rc->config->get('ban_period', 120);
+        $this->repeat_multiplier = $this->rc->config->get('repeat_multiplier', 4);
+        $this->repeat_reset = $this->rc->config->get('repeat_reset', 86400);
+        $this->db_table = $this->rc->config->get('db_table', 'defense');
+        $this->db_expire = $this->rc->config->get('db_expire', 40);
+        $this->log_pwd = $this->rc->config->get('log_pwd', false);
+        
+        // set client ip
+        $this->ipaddr = rcmail_remote_ip();
+        
+        // Roundcube event hooks
+        $this->add_hook('template_object_loginform', array($this, 'hookLoginForm'));
+        $this->add_hook('authenticate', array($this, 'authenticate'));
+        $this->add_hook('login_failed', array($this, 'login_failed'));
+    }
+    
+  /**
+    * Process whitelist and blacklist
+    *
+    * @param string Login form HTML
+    * @return string Login form HTML
+    */
+    public function hookLoginForm($content) {
+        // If IP is listed in whitelist, return unmodified $content
+        if (isIPinArray($this->ipaddr, $this->whitelist)) {
+            return $content;
+        }
+        
+        // If IP is listed in blacklist, deny access
+        if (isIPinArray($this->ipaddr, $this->blacklist)) {
+            header('HTTP/1.1 403 Forbidden');
+            die();
+        }
+    }
+}
+ 
+ 
+ 
+?>