protected function doSign()
{
foreach ($this->bodySigners as $signer) {
$altered = $signer->getAlteredHeaders();
$this->saveHeaders($altered);
$signer->signMessage($this);
}
foreach ($this->headerSigners as $signer) {
$altered = $signer->getAlteredHeaders();
$this->saveHeaders($altered);
$signer->reset();
$signer->setHeaders($this->getHeaders());
$signer->startBody();
$this->bodyToByteStream($signer);
$signer->endBody();
$signer->addSignature($this->getHeaders());
}
}