encryption proxy wip

3 files changed, 202 insertions, 0 deletions

diff --git a/apps/files_encryption/appinfo/app.php b/apps/files_encryption/appinfo/app.php
new file mode 100644
index 00000000000..82d2544dd14
--- /dev/null
+++ b/apps/files_encryption/appinfo/app.php
@@ -0,0 +1,11 @@
+<?php
+
+OC::$CLASSPATH['OC_Crypt'] = 'apps/files_encryption/lib/crypt.php';
+OC::$CLASSPATH['OC_CryptStream'] = 'apps/files_encryption/lib/cryptstream.php';
+OC::$CLASSPATH['OC_FileProxy_Encryption'] = 'apps/files_encryption/lib/proxy.php';
+
+OC_FileProxy::register(new OC_FileProxy_Encryption());
+
+OC_Hook::connect('OC_User','post_login','OC_Crypt','loginListener');
+
+stream_wrapper_register('crypt','OC_CryptStream');
diff --git a/apps/files_encryption/lib/cryptstream.php b/apps/files_encryption/lib/cryptstream.php
new file mode 100644
index 00000000000..e4544313f63
--- /dev/null
+++ b/apps/files_encryption/lib/cryptstream.php
@@ -0,0 +1,121 @@
+<?php
+/**
+ * ownCloud
+ *
+ * @author Robin Appelman
+ * @copyright 2011 Robin Appelman icewind1991@gmail.com
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library 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 AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * transparently encrypted filestream
+ */
+
+class OC_CryptStream{
+	private $source;
+
+	public function stream_open($path, $mode, $options, &$opened_path){
+		$path=str_replace('crypt://','',$path);
+		$this->source=OC_FileSystem::fopen($path.'.enc',$mode);
+		if(!is_resource($this->source)){
+			OC_Log::write('files_encryption','failed to open '.$path.'.enc',OC_Log::ERROR);
+		}
+		return is_resource($this->source);
+	}
+	
+	public function stream_seek($offset, $whence=SEEK_SET){
+		fseek($this->source,$offset,$whence);
+	}
+	
+	public function stream_tell(){
+		return ftell($this->source);
+	}
+	
+	public function stream_read($count){
+		$pos=0;
+		$currentPos=ftell($this->source);
+		$offset=$currentPos%8192;
+		fseek($this->source,-$offset,SEEK_CUR);
+		$result='';
+		while($count>$pos){
+			$data=fread($this->source,8192);
+			$pos+=8192;
+			$result.=OC_Crypt::decrypt($data);
+		}
+		return substr($result,$offset,$count);
+	}
+	
+	public function stream_write($data){
+		$length=strlen($data);
+		$written=0;
+		$currentPos=ftell($this->source);
+		if($currentPos%8192!=0){
+			//make sure we always start on a block start
+			fseek($this->source,-($currentPos%8192),SEEK_CUR);
+			$encryptedBlock=fread($this->source,8192);
+			fseek($this->source,-($currentPos%8192),SEEK_CUR);
+			$block=OC_Crypt::decrypt($encryptedBlock);
+			$data=substr($block,0,$currentPos%8192).$data;
+		}
+		while(strlen($data)>0){
+			if(strlen($data)<8192){
+				//fetch the current data in that block and append it to the input so we always write entire blocks
+				$oldPos=ftell($this->source);
+				$encryptedBlock=fread($this->source,8192);
+				fseek($this->source,$oldPos);
+				$block=OC_Crypt::decrypt($encryptedBlock);
+				$data.=substr($block,strlen($data));
+			}
+			$encrypted=OC_Crypt::encrypt(substr($data,0,8192));
+			fwrite($this->source,$encrypted);
+			$data=substr($data,8192);
+		}
+		return $length;
+	}
+
+	public function stream_set_option($option,$arg1,$arg2){
+		switch($option){
+			case STREAM_OPTION_BLOCKING:
+				stream_set_blocking($this->source,$arg1);
+				break;
+			case STREAM_OPTION_READ_TIMEOUT:
+				stream_set_timeout($this->source,$arg1,$arg2);
+				break;
+			case STREAM_OPTION_WRITE_BUFFER:
+				stream_set_write_buffer($this->source,$arg1,$arg2);
+		}
+	}
+
+	public function stream_stat(){
+		return fstat($this->source);
+	}
+	
+	public function stream_lock($mode){
+		flock($this->source,$mode);
+	}
+	
+	public function stream_flush(){
+		return fflush($this->source);
+	}
+
+	public function stream_eof(){
+		return feof($this->source);
+	}
+
+	public function stream_close(){
+		return fclose($this->source);
+	}
+}
\ No newline at end of file
diff --git a/apps/files_encryption/lib/proxy.php b/apps/files_encryption/lib/proxy.php
new file mode 100644
index 00000000000..f7a991a344b
--- /dev/null
+++ b/apps/files_encryption/lib/proxy.php
@@ -0,0 +1,70 @@
+<?php
+
+/**
+* ownCloud
+*
+* @author Robin Appelman
+* @copyright 2011 Robin Appelman icewind1991@gmail.com
+*
+* This library is free software; you can redistribute it and/or
+* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+* License as published by the Free Software Foundation; either
+* version 3 of the License, or any later version.
+*
+* This library 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 AFFERO GENERAL PUBLIC LICENSE for more details.
+*
+* You should have received a copy of the GNU Affero General Public
+* License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+*
+*/
+
+/**
+ * transparent encryption
+ */
+
+class OC_FileProxy_Encryption extends OC_FileProxy{
+	public function preFile_put_contents($path,&$data){
+		if(substr($path,-4)=='.enc'){
+			OC_Log::write('files_encryption','file put contents',OC_Log::DEBUG);
+			if (is_resource($data)) {
+				$newData='';
+				while(!feof($data)){
+					$block=fread($data,8192);
+					$newData.=OC_Crypt::encrypt($block);
+				}
+				$data=$newData;
+			}else{
+				$data=OC_Crypt::blockEncrypt($data);
+			}
+		}
+	}
+	
+	public function postFile_get_contents($path,$data){
+		if(substr($path,-4)=='.enc'){
+			OC_Log::write('files_encryption','file get contents',OC_Log::DEBUG);
+			return OC_Crypt::blockDecrypt($data);
+		}
+	}
+	
+	public function postFopen($path,&$result){
+		if(substr($path,-4)=='.enc'){
+			OC_Log::write('files_encryption','fopen',OC_Log::DEBUG);
+			fclose($result);
+			$result=fopen('crypt://'.substr($path,0,-4));//remove the .enc extention so we don't catch the fopen request made by cryptstream
+		}
+	}
+	
+	public function preReadFile($path){
+		if(substr($path,-4)=='.enc'){
+			OC_Log::write('files_encryption','readline',OC_Log::DEBUG);
+			$stream=fopen('crypt://'.substr($path,0,-4));
+			while(!feof($stream)){
+				print(fread($stream,8192));
+			}
+			return false;//cancel the original request
+		}
+	}
+}