diff options
Diffstat (limited to 'lib/private/Files/Stream/Encryption.php')
| -rw-r--r-- | lib/private/Files/Stream/Encryption.php | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/lib/private/Files/Stream/Encryption.php b/lib/private/Files/Stream/Encryption.php index 3c884a99ae7..d6e40655394 100644 --- a/lib/private/Files/Stream/Encryption.php +++ b/lib/private/Files/Stream/Encryption.php @@ -315,6 +315,31 @@ class Encryption extends Wrapper { return $result; } + + /** + * stream_read_block + * + * This function is a wrapper for function stream_read. + * It calls stream read until the requested $blockSize was received or no remaining data is present. + * This is required as stream_read only returns smaller chunks of data when the stream fetches from a + * remote storage over the internet and it does not care about the given $blockSize. + * + * @param int $blockSize Length of requested data block in bytes + * @return string Data fetched from stream. + */ + private function stream_read_block(int $blockSize): string { + $remaining = $blockSize; + $data = ''; + + do { + $chunk = parent::stream_read($remaining); + $chunk_len = strlen($chunk); + $data .= $chunk; + $remaining -= $chunk_len; + } while (($remaining > 0) && ($chunk_len > 0)); + + return $data; + } public function stream_write($data) { $length = 0; @@ -470,7 +495,7 @@ class Encryption extends Wrapper { // don't try to fill the cache when trying to write at the end of the unencrypted file when it coincides with new block if ($this->cache === '' && !($this->position === $this->unencryptedSize && ($this->position % $this->unencryptedBlockSize) === 0)) { // Get the data from the file handle - $data = parent::stream_read($this->util->getBlockSize()); + $data = $this->stream_read_block($this->util->getBlockSize()); $position = (int)floor($this->position/$this->unencryptedBlockSize); $numberOfChunks = (int)($this->unencryptedSize / $this->unencryptedBlockSize); if($numberOfChunks === $position) { @@ -495,7 +520,7 @@ class Encryption extends Wrapper { * read first block to skip the header */ protected function skipHeader() { - parent::stream_read($this->headerSize); + $this->stream_read_block($this->headerSize); } /** |