rework getFileSize

diff --git a/apps/files_encryption/lib/util.php b/apps/files_encryption/lib/util.php
index 33c2f88b0fde8b019fe38c781109b4a3cea86712..3cf83703295841627ae751993e43d110730aa01e 100644 (file)
--- a/apps/files_encryption/lib/util.php
+++ b/apps/files_encryption/lib/util.php
@@ -385,15 +385,24 @@ class Util {
                        && $this->isEncryptedPath($path)
                ) {
 
-                       $offset = 0;
+                       $cipher = Helper::getCipher();
+                       $realSize = 0;
+
+                       // get the size from filesystem
+                       $size = $this->view->filesize($path);
+
+                       // open stream
+                       $stream = fopen($path, "r");
+
+                       // if the file contains a encryption header we
+                       // we set the cipher
+                       // and we update the size
                        if ($this->containHeader($path)) {
-                               $offset = Crypt::BLOCKSIZE;
+                               $header = fread($stream,Crypt::BLOCKSIZE);
+                               $cipher = Crypt::getCipher($header);
+                               $size -= Crypt::BLOCKSIZE;
                        }
 
-                       // get the size from filesystem if the file contains a encryption header we
-                       // we substract it
-                       $size = $this->view->filesize($path) - $offset;
-
                        // fast path, else the calculation for $lastChunkNr is bogus
                        if ($size === 0) {
                                \OC_FileProxy::$enabled = $proxyStatus;
@@ -403,37 +412,45 @@ class Util {
                        // calculate last chunk nr
                        // next highest is end of chunks, one subtracted is last one
                        // we have to read the last chunk, we can't just calculate it (because of padding etc)
-                       $lastChunkNr = ceil($size/ Crypt::BLOCKSIZE) - 1;
-                       $lastChunkSize = $size - ($lastChunkNr * Crypt::BLOCKSIZE);
-
-                       // open stream
-                       $stream = fopen('crypt://' . $path, "r");
+                       $lastChunkNr = ceil($size/Crypt::BLOCKSIZE)-1;
 
                        if (is_resource($stream)) {
                                // calculate last chunk position
-                               $lastChunckPos = ($lastChunkNr * Crypt::BLOCKSIZE);
+                               $lastChunkPos = ($lastChunkNr * Crypt::BLOCKSIZE);
 
-                               // seek to end
-                               if (@fseek($stream, $lastChunckPos) === -1) {
-                                       // storage doesn't support fseek, we need a local copy
-                                       fclose($stream);
-                                       $localFile = $this->view->getLocalFile($path);
-                                       Helper::addTmpFileToMapper($localFile, $path);
-                                       $stream = fopen('crypt://' . $localFile, "r");
-                                       if (fseek($stream, $lastChunckPos) === -1) {
-                                               // if fseek also fails on the local storage, than
-                                               // there is nothing we can do
-                                               fclose($stream);
-                                               \OCP\Util::writeLog('Encryption library', 'couldn\'t determine size of "' . $path, \OCP\Util::ERROR);
-                                               return $result;
+                               // get the content of the last chunk
+                               $lastChunkContentEncrypted='';
+                               $count=Crypt::BLOCKSIZE;
+                               if (@fseek($stream, $lastChunkPos, SEEK_CUR) === 0) {
+                                       $realSize+=$lastChunkNr*6126;
+                                       while ($count>0) {
+                                               $data=fread($stream,Crypt::BLOCKSIZE);
+                                               $count=strlen($data);
+                                               $lastChunkContentEncrypted.=$data;
+                                       }
+                               } else {
+                                       while ($count>0) {
+                                               if(strlen($lastChunkContentEncrypted)>Crypt::BLOCKSIZE) {
+                                                       $realSize+=6126;
+                                                       $lastChunkContentEncrypted=substr($lastChunkContentEncrypted,Crypt::BLOCKSIZE);
+                                               }
+                                               $data=fread($stream,Crypt::BLOCKSIZE);
+                                               $count=strlen($data);
+                                               $lastChunkContentEncrypted.=$data;
                                        }
                                }
 
-                               // get the content of the last chunk
-                               $lastChunkContent = fread($stream, $lastChunkSize);
+                               $session = new \OCA\Encryption\Session(new \OC\Files\View('/'));
+                               $privateKey = $session->getPrivateKey();
+                               $plainKeyfile = $this->decryptKeyfile($path, $privateKey);
+                               $shareKey = Keymanager::getShareKey($this->view, $this->keyId, $this, $path);
+
+                               $plainKey = Crypt::multiKeyDecrypt($plainKeyfile, $shareKey, $privateKey);
+                               
+                               $lastChunkContent=Crypt::symmetricDecryptFileContent($lastChunkContentEncrypted, $plainKey, $cipher);
 
                                // calc the real file size with the size of the last chunk
-                               $realSize = (($lastChunkNr * 6126) + strlen($lastChunkContent));
+                               $realSize += strlen($lastChunkContent);
 
                                // store file size
                                $result = $realSize;