void SshChannelManager::handleChannelOpenFailure(const SshIncomingPacket &packet)
{
   const SshChannelOpenFailure &failure = packet.extractChannelOpenFailure();
   ChannelIterator it = lookupChannelAsIterator(failure.localChannel);
   try {
       it.value()->handleOpenFailure(failure.reasonString);
   } catch (SshServerException &e) {
       removeChannel(it);
       throw e;
   }
   removeChannel(it);
}