OCA\Encryption\Crypto\Encryption::encrypt()

Complexity

Conditions	4
Paths	6

Size

Total Lines	52
Code Lines	14

Duplication

Lines	0
Ratio	0 %

Importance

Changes

0

<?php
	public function encrypt($data, $position = 0) {
		// If extra data is left over from the last round, make sure it
		// is integrated into the next block
		if ($this->writeCache) {

			// Concat writeCache to start of $data
			$data = $this->writeCache . $data;

			// Clear the write cache, ready for reuse - it has been
			// flushed and its old contents processed
			$this->writeCache = '';
		}

		$encrypted = '';
		// While there still remains some data to be processed & written
		while (strlen($data) > 0) {

			// Remaining length for this iteration, not of the
			// entire file (may be greater than 8192 bytes)
			$remainingLength = strlen($data);

			// If data remaining to be written is less than the
			// size of 1 6126 byte block
			if ($remainingLength < $this->unencryptedBlockSizeSigned) {

				// Set writeCache to contents of $data
				// The writeCache will be carried over to the
				// next write round, and added to the start of
				// $data to ensure that written blocks are
				// always the correct length. If there is still
				// data in writeCache after the writing round
				// has finished, then the data will be written
				// to disk by $this->flush().
				$this->writeCache = $data;

				// Clear $data ready for next round
				$data = '';
			} else {

				// Read the chunk from the start of $data
				$chunk = substr($data, 0, $this->unencryptedBlockSizeSigned);

				$encrypted .= $this->crypt->symmetricEncryptFileContent($chunk, $this->fileKey, $this->version + 1, $position);

				// Remove the chunk we just processed from
				// $data, leaving only unprocessed data in $data
				// var, for handling on the next round
				$data = substr($data, $this->unencryptedBlockSizeSigned);
			}
		}

		return $encrypted;
	}