From d98d23ff5be54a8f9210730fc64ff6fa37ce954c Mon Sep 17 00:00:00 2001
From: Wytze van der Raay <wytze@cacert.org>
Date: Wed, 7 Sep 2011 10:30:32 +0000
Subject: [PATCH] Fix for https://bugs.cacert.org/view.php?id=841 (Problems on
 cert login with "duplicate" serial numbers)

---
 includes/lib/general.php | 50 ++++++++++++++++++++++++++++++++++++++++
 includes/loggedin.php    | 13 +++++------
 www/index.php            | 15 +++++++-----
 3 files changed, 65 insertions(+), 13 deletions(-)
 create mode 100644 includes/lib/general.php

diff --git a/includes/lib/general.php b/includes/lib/general.php
new file mode 100644
index 0000000..25d2561
--- /dev/null
+++ b/includes/lib/general.php
@@ -0,0 +1,50 @@
+<? /*
+    LibreSSL - CAcert web application
+    Copyright (C) 2004-2011  CAcert Inc.
+
+    This program 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; version 2 of the License.
+
+    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 more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+/**
+ * Checks if the user may log in and retrieve the user id
+ * 
+ * Usually called with $_SERVER['SSL_CLIENT_M_SERIAL'] and
+ * 	$_SERVER['SSL_CLIENT_I_DN_CN']
+ * 
+ * @param $serial string
+ * 	usually $_SERVER['SSL_CLIENT_M_SERIAL']
+ * @param $issuer_cn string
+ * 	usually $_SERVER['SSL_CLIENT_I_DN_CN']
+ * @return int
+ * 	the user id, -1 in case of error
+ */
+function get_user_id_from_cert($serial, $issuer_cn)
+{
+	$query = "select `memid` from `emailcerts` where
+			`serial`='".mysql_escape_string($serial)."' and
+			`rootcert`= (select `id` from `root_certs` where
+				`Cert_Text`='".mysql_escape_string($issuer_cn)."') and
+			`revoked`=0 and disablelogin=0 and
+			UNIX_TIMESTAMP(`expire`) - UNIX_TIMESTAMP() > 0";
+	$res = mysql_query($query);
+	if(mysql_num_rows($res) > 0)
+	{
+		$row = mysql_fetch_assoc($res);
+		return intval($row['memid']);
+	}
+	
+	return -1;
+}
+
+?>
diff --git a/includes/loggedin.php b/includes/loggedin.php
index 640bc6c..bf6b455 100644
--- a/includes/loggedin.php
+++ b/includes/loggedin.php
@@ -16,6 +16,7 @@
     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
+	include_once("../includes/lib/general.php");
 
 	if($_SERVER['HTTP_HOST'] == $_SESSION['_config']['securehostname'] && $_SESSION['profile']['id'] > 0 && $_SESSION['profile']['loggedin'] != 0)
 	{
@@ -41,14 +42,11 @@
   
 	if($_SERVER['HTTP_HOST'] == $_SESSION['_config']['securehostname'] && ($_SESSION['profile']['id'] == 0 || $_SESSION['profile']['loggedin'] == 0))
 	{
-		$query = "select * from `emailcerts` where `serial`='${_SERVER['SSL_CLIENT_M_SERIAL']}' and `revoked`=0 and disablelogin=0 and
-				UNIX_TIMESTAMP(`expire`) - UNIX_TIMESTAMP() > 0";
-		$res = mysql_query($query);
+		$user_id = get_user_id_from_cert($_SERVER['SSL_CLIENT_M_SERIAL'],
+				$_SERVER['SSL_CLIENT_I_DN_CN']);
 
-		if(mysql_num_rows($res) > 0)
+		if($user_id >= 0)
 		{
-			$row = mysql_fetch_assoc($res);
-
 			$_SESSION['profile']['loggedin'] = 0;
 			$_SESSION['profile'] = "";
 			foreach($_SESSION as $key)
@@ -61,7 +59,8 @@
        			        session_unregister($key);
 			}
 
-			$_SESSION['profile'] = mysql_fetch_assoc(mysql_query("select * from `users` where `id`='".$row['memid']."'"));
+			$_SESSION['profile'] = mysql_fetch_assoc(mysql_query(
+					"select * from `users` where `id`='".$user_id."'"));
 			if($_SESSION['profile']['locked'] == 0)
 				$_SESSION['profile']['loggedin'] = 1;
 			else
diff --git a/www/index.php b/www/index.php
index 7330877..a4c50fc 100644
--- a/www/index.php
+++ b/www/index.php
@@ -148,13 +148,16 @@
 
 	if($id == 4 && $_SERVER['HTTP_HOST'] == $_SESSION['_config']['securehostname'])
 	{
-		$query = "select * from `emailcerts` where `serial`='$_SERVER[SSL_CLIENT_M_SERIAL]' and `revoked`=0 and disablelogin=0 and
-				UNIX_TIMESTAMP(`expire`) - UNIX_TIMESTAMP() > 0";
-		$res = mysql_query($query);
-		if(mysql_num_rows($res) > 0)
+		include_once("../includes/lib/general.php");
+		$user_id = get_user_id_from_cert($_SERVER['SSL_CLIENT_M_SERIAL'],
+				$_SERVER['SSL_CLIENT_I_DN_CN']);
+		
+		if($user_id >= 0)
 		{
-			$row = mysql_fetch_assoc($res);
-			$_SESSION['profile'] = mysql_fetch_assoc(mysql_query("select * from `users` where `id`='$row[memid]' and `deleted`=0 and `locked`=0"));
+			$_SESSION['profile'] = mysql_fetch_assoc(mysql_query(
+				"select * from `users` where 
+				`id`='$user_id' and `deleted`=0 and `locked`=0"));
+			
 			if($_SESSION['profile']['id'] != 0)
 			{
 				$_SESSION['profile']['loggedin'] = 1;