api_handler.php

<?php
require_once('lib/include.php');
// For encrypting nonce
require_once('openpgpphp/lib/openpgp.php');
require_once('openpgpphp/lib/openpgp_crypt_rsa.php');
require_once('openpgpphp/lib/openpgp_crypt_aes_tripledes.php');

if (!isset($_GET['method']))
{
  exit();
}
 

switch ($_GET['method'])
  {
    // Request a public key for some email address which may be using Safer Email
  case "get_public_key":
    get_public_key($_GET['email']);
    break;
    // Determine if an email address is taken
  case "user_exists":
    user_exists($_GET['email']);
    break;
    // Logoff
  case "logoff":
    unset($_SESSION['user']);
    break;
    // Fetch a single message
  case "delete_message":
    delete_message($_GET['id']);
    break;
  case "get_message":
    get_message($_GET['id']);
    break;
    // Get an encrypted nonce
  case "get_enc_nonce":
    gen_nonce($_GET['email']);
    break;
    // Get a user's encrypted private key
  case "get_enc_privkey":
    get_enc_privkey($_GET['email']);
    break;
    // Send message
  case "send":
    send_message($_POST['email'], $_POST['subject'], $_POST['message'], $_POST['post']);
    break;
  default:
    break;
  }

function get_enc_privkey($email)
{
  $u = UserQuery::create()->findOneByEmail($email);
  if ($u === NULL)
    return;
  print $u->getEncprivkey();
}

function gen_nonce($email)
{  
  $u = UserQuery::create()->findOneByEmail($email);
  if ($u === NULL)
    return;
  
  $key = OpenPGP_Message::parse(OpenPGP::unarmor($u->getPubkey()));
  $rn = SMAIL_SALT.rand();
  $_SESSION['loginemail'] = $email;
  $_SESSION['nonce'] = $rn;
  $data = new OpenPGP_LiteralDataPacket($rn, array('format' => 'u'));
  $enc = OpenPGP_Crypt_AES_TripleDES::encrypt($key, new OpenPGP_Message(array($data)));
  print OpenPGP::enarmor($enc->to_bytes(), "PGP MESSAGE");
}

function delete_message($id)
{
  if (!isset($_SESSION['user']))
    return;
  $user = unserialize($_SESSION['user']);
  $msg = MessageQuery::create()->filterByUserId($user->getId())->findPk($id);
  if ($msg != NULL)
    $msg->delete();
}

function get_message($id)
{
  if (!isset($_SESSION['user']))
    return;
  $user = unserialize($_SESSION['user']);
  $msg = MessageQuery::create()->filterByUserId($user->getId())->findPk($id);

  if ($msg != NULL)
    {
      print json_encode(Array("message" => $msg->getMBody(), "from" => $msg->getSender(), "subject" => $msg->getSubject(), "timestamp" => $msg->getTimeStamp()->format('Y-m-d H:i:s')));
    }
}

function send_message($email, $subject, $message, $post)
{
  if (!isset($_SESSION['user']))
    return;
  $user = unserialize($_SESSION['user']);
  if ($post == 'true')
    {
      $exploded_email = explode('@', $email);
      $domain = $exploded_email[1];
      $username = $exploded_email[0];
      
      if ($domain == SMAIL_DOMAIN)
	{
	  $fu = unserialize($_SESSION['user']);
	  $fromemail = $fu->getName().' <'.$fu->getEmail().'>';
	  $u = UserQuery::create()->findOneByEmail($email);  
	  
	  $msg = new Message();
	  $msg->setMBody($message);
    	  $msg->setSender($fromemail);
    	  $msg->setSubject($subject);
	  $msg->setUserId($u->getId());

    	  $msg->save();
	}
      else
	{
	  $records = dns_get_record($domain, DNS_TXT);
	  for ($i = 0; $i < count($records); $i++)
	    {
	      foreach ($records[$i]['entries'] as $record)
		{
		  if (preg_match('/^v=shmp1 http/', $record))
		    {
		      // TODO Switch to http_build_query
		      $fields_string = '';
		      $fields = array(
		      	      'subject' => urlencode($subject),
			      'message' => urlencode($message),
			      'to' => urlencode($email),
			      'from' => urlencode($user->name.' <'.$user->email.'>')
			      );
		      foreach($fields as $key=>$value) { $fields_string .= $key.'='.$value.'&'; }
		      rtrim($fields_string, '&');
		      $ch = curl_init();
		      curl_setopt($ch, CURLOPT_URL, preg_replace('/^v=shmp1 /', '', $record));
		      curl_setopt($ch, CURLOPT_POST, count($fields));
		      curl_setopt($ch, CURLOPT_POSTFIELDS, $fields_string);
		      curl_exec($ch);
		      curl_close($ch);
		    }
		}
	    }
	} 
    }
  else
    {
      mail($email, $subject, $message, 'From: '.$user->getName().' <'.$user->getEmail().'>');
    }
}

function user_exists($email)
{
  $u = UserQuery::create()->findOneByEmail($email);
  if($u !== NULL)
    print "true";
  else
    print "false";
}

function get_public_key($email)
{
  $exploded_email = explode('@', $email);
  $domain = $exploded_email[1];
  $username = $exploded_email[0];

  if ($domain == SMAIL_DOMAIN)
    {
      $u = UserQuery::create()->findOneByEmail($email);	
      if ($u != NULL)
        print $u->getPubkey();
    }
  else
    {
      $records = dns_get_record($domain, DNS_TXT);
      for ($i = 0; $i < count($records); $i++)
	{
	  foreach ($records[$i]['entries'] as $record)
	    {
	      if (preg_match('/^v=shmk1 http/', $record))
		{
		  // Use that address to get public key
		  print file_get_contents(preg_replace('/^v=shmk1 /', '', $record).'?email='.$email);
		}
	    }
	}
    }
}

function strip_numeric($var)
{
  return !is_numeric($var);
}

?>