--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sessions.php	Mon Sep 01 16:51:13 2008 -0400
@@ -0,0 +1,177 @@
+<?php
+
+/**
+ * Greyhound - real web management for Amarok
+ * Copyright (C) 2008 Dan Fuhry
+ *
+ * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
+ *
+ * This program 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 details.
+ */
+
+function greyhound_login_page($httpd, $socket)
+{
+  if ( session_check() )
+  {
+    $httpd->header('HTTP/1.1 307 Temporary Redirect');
+    $httpd->header('Location: /');
+    
+    return;
+  }
+  $tried = false;
+  $success = false;
+  if ( isset($_POST['username']) && isset($_POST['password']) )
+  {
+    $tried = true;
+    if ( $sessionid = login($_POST['username'], $_POST['password']) )
+    {
+      $success = true;
+      $httpd->setcookie('grey_session', $sessionid, time() + ( 86400 * 3650 ));
+    }
+  }
+  
+  global $theme;
+  $iphone = ( ( strpos($_SERVER['HTTP_USER_AGENT'], 'iPhone') ||
+       strpos($_SERVER['HTTP_USER_AGENT'], 'iPod') ||
+       strpos($_SERVER['HTTP_USER_AGENT'], 'BlackBerry') ||
+       isset($_GET['m']) )
+       && !isset($_GET['f'])
+       );
+  $theme_id = ( $iphone ) ? 'iphone' : $theme;
+  $smarty = load_theme($theme_id);
+  
+  $smarty->assign('theme', $theme_id);
+  $smarty->assign('greyhound_version', GREY_VERSION);
+  $smarty->assign('tried', $tried);
+  $smarty->assign('success', $success);
+  $smarty->display('login.tpl');
+}
+
+function greyhound_logout($httpd, $socket)
+{
+  // destroy the session
+  if ( isset($_COOKIE['grey_session']) )
+  {
+    load_session_data();
+    global $session_data;
+    unset($session_data[$_COOKIE['grey_session']]);
+    session_commit_db();
+  }
+  
+  $httpd->setcookie('grey_session', '', time() - 864000);
+  $httpd->header('HTTP/1.1 307 Temporary Redirect');
+  $httpd->header('Location: /');
+}
+
+/**
+ * Check to see if we're logged in
+ */
+
+function session_check()
+{
+  global $use_auth, $auth_data;
+  if ( isset($_COOKIE['grey_session']) )
+  {
+    load_session_data();
+    global $session_data;
+    if ( isset($session_data[$_COOKIE['grey_session']]) )
+    {
+      // has a cookie with a valid session ID, check credentials
+      $session =& $session_data[$_COOKIE['grey_session']];
+      if ( isset($auth_data[$session['user']]) )
+      {
+        if ( $session['hash'] === md5($auth_data[$session['user']] . $session['salt']) )
+        {
+          // session is valid, logged in
+          return true;
+        }
+      }
+    }
+  }
+  return ( $use_auth ) ? false : true;
+}
+
+function login($username, $password)
+{
+  global $use_auth, $auth_data;
+  if ( !$use_auth )
+    return false;
+  
+  if ( isset($auth_data[$username]) )
+  {
+    if ( $auth_data[$username] === $password )
+    {
+      return create_session($username, $password);
+    }
+  }
+  return false;
+}
+
+function create_session($username, $password)
+{
+  load_session_data();
+  global $session_data;
+  
+  $sessid = md5(sha1(microtime() . mt_rand()));
+  $salt = md5(sha1(md5(mt_rand() . microtime() . microtime() . mt_rand())));
+  
+  $session_data[$sessid] = array(
+      'user' => $username,
+      'hash' => md5($password . $salt),
+      'salt' => $salt
+    );
+  session_commit_db();
+  
+  return $sessid;
+}
+
+function var_export_string($arr)
+{
+  ob_start();
+  var_export($arr);
+  $r = ob_get_contents();
+  ob_end_clean();
+  return $r;
+}
+
+function session_commit_db()
+{
+  global $session_data;
+  $d = var_export_string($session_data);
+  $fp = @fopen('./session_db.php', 'w');
+  if ( !$fp )
+  {
+    warning('Could not open the session database for writing. Logins may not work.');
+    return false;
+  }
+  $d = <<<EOF
+<?php
+
+// Automatically generated session database for Greyhound. Do not edit this file!
+
+\$GLOBALS['session_data'] = $d;
+EOF;
+  
+  fwrite($fp, $d);
+  fclose($fp);
+  
+  return true;
+}
+
+function load_session_data()
+{
+  if ( file_exists('./session_db.php') )
+  {
+    require('./session_db.php');
+  }
+  else
+  {
+    $GLOBALS['session_data'] = array();
+  }
+}
+
+$session_data = array();
+
+?>