/** * start receiving chunks from a file. This is the place where you can * perform some initial step before starting encrypting/decrypting the * chunks * * @param string $path to the file * @param string $user who read/write the file * @param string $mode php stream open mode * @param array $header contains the header data read from the file * @param array $accessList who has access to the file contains the key 'users' and 'public' * * @return array $header contain data as key-value pairs which should be * written to the header, in case of a write operation * or if no additional data is needed return a empty array */ public function begin($path, $user, $mode, array $header, array $accessList) { $this->path = $this->getPathToRealFile($path); $this->accessList = $accessList; $this->user = $user; $this->isWriteOperation = false; $this->writeCache = ''; $this->fileKey = $this->keyManager->getFileKey($this->path, $this->user); if ($mode === 'w' || $mode === 'w+' || $mode === 'wb' || $mode === 'wb+') { $this->isWriteOperation = true; if (empty($this->fileKey)) { $this->fileKey = $this->crypt->generateFileKey(); } } if (isset($header['cipher'])) { $this->cipher = $header['cipher']; } elseif ($this->isWriteOperation) { $this->cipher = $this->crypt->getCipher(); } else { // if we read a file without a header we fall-back to the legacy cipher // which was used in <=oC6 $this->cipher = $this->crypt->getLegacyCipher(); } return array('cipher' => $this->cipher); }
/** * encrypt data * * @param string $data you want to encrypt * @return mixed encrypted data */ public function encrypt($data) { $this->isWriteOperation = true; if (empty($this->fileKey)) { $this->fileKey = $this->crypt->generateFileKey(); } // If extra data is left over from the last round, make sure it // is integrated into the next 6126 / 8192 block if ($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 < 6126) { // 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, 6126); $encrypted .= $this->crypt->symmetricEncryptFileContent($chunk, $this->fileKey); // Remove the chunk we just processed from // $data, leaving only unprocessed data in $data // var, for handling on the next round $data = substr($data, 6126); } } return $encrypted; }
/** * start receiving chunks from a file. This is the place where you can * perform some initial step before starting encrypting/decrypting the * chunks * * @param string $path to the file * @param string $user who read/write the file * @param string $mode php stream open mode * @param array $header contains the header data read from the file * @param array $accessList who has access to the file contains the key 'users' and 'public' * * @return array $header contain data as key-value pairs which should be * written to the header, in case of a write operation * or if no additional data is needed return a empty array */ public function begin($path, $user, $mode, array $header, array $accessList) { $this->path = $this->getPathToRealFile($path); $this->accessList = $accessList; $this->user = $user; $this->isWriteOperation = false; $this->writeCache = ''; if ($this->session->decryptAllModeActivated()) { $encryptedFileKey = $this->keyManager->getEncryptedFileKey($this->path); $shareKey = $this->keyManager->getShareKey($this->path, $this->session->getDecryptAllUid()); $this->fileKey = $this->crypt->multiKeyDecrypt($encryptedFileKey, $shareKey, $this->session->getDecryptAllKey()); } else { $this->fileKey = $this->keyManager->getFileKey($this->path, $this->user); } // always use the version from the original file, also part files // need to have a correct version number if they get moved over to the // final location $this->version = (int) $this->keyManager->getVersion($this->stripPartFileExtension($path), new View()); if ($mode === 'w' || $mode === 'w+' || $mode === 'wb' || $mode === 'wb+') { $this->isWriteOperation = true; if (empty($this->fileKey)) { $this->fileKey = $this->crypt->generateFileKey(); } } else { // if we read a part file we need to increase the version by 1 // because the version number was also increased by writing // the part file if (Scanner::isPartialFile($path)) { $this->version = $this->version + 1; } } if ($this->isWriteOperation) { $this->cipher = $this->crypt->getCipher(); } elseif (isset($header['cipher'])) { $this->cipher = $header['cipher']; } else { // if we read a file without a header we fall-back to the legacy cipher // which was used in <=oC6 $this->cipher = $this->crypt->getLegacyCipher(); } return array('cipher' => $this->cipher, 'signed' => 'true'); }