/**
* {@inheritdoc}
*/
public function writeToStream(SplFileObject $fileObject, $encryptionKey)
{
$value = $this->value;
if (null !== $encryptionKey) {
$value = \Bacon\Pdf\Utils\EncryptionUtils::rc4($encryptionKey, $value);
}
$fileObject->fwrite('<');
$fileObject->fwrite(chunk_split(bin2hex($value), 255, "\n"));
$fileObject->fwrite('>');
}
/**
* {@inheritdoc}
*/
public function writeToStream(SplFileObject $fileObject, $encryptionKey)
{
$this['Length'] = new NumericObject(strlen($this->data));
parent::writeToStream($fileObject, $encryptionKey);
unset($this['Length']);
$fileObject->fwrite("\nstream\n");
$data = $this->data;
if (null !== $encryptionKey) {
$data = EncryptionUtils::rc4($encryptionKey, $data);
}
$fileObject->fwrite($data);
$fileObject->fwrite("\nendstream");
}
/**
* @param string $permanentFileIdentifier
* @param string $userPassword
* @param string|null $ownerPassword
* @param Permissions|null $userPermissions
* @throws UnexpectedValueException
*/
public function __construct($permanentFileIdentifier, $userPassword, $ownerPassword = null, Permissions $userPermissions = null)
{
if (null === $ownerPassword) {
$ownerPassword = $userPassword;
}
$encodedUserPassword = $this->encodePassword($userPassword);
$encodedOwnerPassword = $this->encodePassword($ownerPassword);
$revision = $this->getRevision();
$keyLength = $this->getKeyLength();
if ($revision < 3 && null !== $userPermissions) {
throw new DomainException('This encryption does not support permissions');
}
if (!in_array($keyLength, [40, 128])) {
throw new UnexpectedValueException('Key length must be either 40 or 128');
}
$this->ownerEntry = $this->computeOwnerEntry($encodedOwnerPassword, $encodedUserPassword, $revision, $keyLength);
if (2 === $revision) {
list($this->userEntry, $this->encryptionKey) = EncryptionUtils::computeUserEntryRev2($encodedUserPassword, $this->ownerEntry, $revision, $permanentFileIdentifier);
} else {
list($this->userEntry, $this->encryptionKey) = EncryptionUtils::computeUserEntryRev3OrGreater($encodedUserPassword, $revision, $keyLength, $this->ownerEntry, $userPermissions->toInt($revision), $permanentFileIdentifier);
}
$this->userPermissions = $userPermissions;
}
/**
* Enables encryption for the document.
*
* @param string $userPassword
* @param string|null $ownerPassword
* @param bool $use128bit
*/
public function enableEncryption($userPassword, $ownerPassword = null, $use128bit = true)
{
if (null === $ownerPassword) {
$ownerPassword = $userPassword;
}
if ($use128bit) {
$algorithm = 2;
$revision = 3;
$keyLength = 128 / 8;
} else {
$algorithm = 1;
$revision = 2;
$keyLength = 40 / 8;
}
$permissions = -1;
$ownerEntry = EncryptionUtils::computeOwnerEntry($ownerPassword, $userPassword, $revision, $keyLength);
if (2 === $revision) {
list($userEntry, $key) = EncryptionUtils::computeUserEntryRev2($userPassword, $ownerEntry, $revision, $this->firstId->getValue());
} else {
list($userEntry, $key) = EncryptionUtils::computeUserEntryRev3OrGreater($userPassword, $revision, $keyLength, $ownerEntry, $permissions, $this->firstId->getValue());
}
$encrypt = new DictionaryObject();
$encrypt['Filter'] = new NameObject('Standard');
$encrypt['V'] = new NumericObject($algorithm);
if (2 === $algorithm) {
$encrypt['Length'] = new NumericObject($keyLength * 8);
}
$encrypt['R'] = new NumericObject($revision);
$encrypt['O'] = new HexadecimalStringObject($ownerEntry);
$encrypt['U'] = new HexadecimalStringObject($userEntry);
$encrypt['P'] = new NumericObject($permissions);
$this->encrypt = $this->objects->addObject($encrypt);
$this->encryptionKey = $key;
}
