NAME

       Net::SIP::StatelessProxy - Simple implementation of a stateless proxy

SYNOPSIS

       ..

DESCRIPTION

       This package implements a simple stateless SIP proxy.  Basic idea is that the proxy has
       either a single or two legs and that the packets are exchanged between those legs, e.g.
       packets incoming on one leg will be forwarded through the other leg.

       Because this is a stateless proxy no retransmits will be done by the proxy.

       If the proxy should work as a registrar too it should be put after a Net::SIP::Registrar
       in a Net::SIP::ReceiveChain.

       While forwarding the proxy will be insert itself into the packet, e.g. it will add Via and
       Record-Route header while forwarding requests.

       Additionally it will rewrite the Contact header while forwarding packets (see below), e.g.
       if the Contact header points to some client it will rewrite it, so that it points to the
       proxy and if it already points to the proxy it will rewrite it back so that it again
       points to the client.

CONSTRUCTOR

       new ( %ARGS )
           Creates a new stateless proxy. With %ARGS the behavior can be influenced:

           dispatcher
                   The Net::SIP::Dispatcher object managing the proxy.

           rewrite_contact
                   Callback which is used in rewriting Contact headers.  If one puts user@host in
                   it should rewrite it and if one puts something without '@' it should try to
                   rewrite it back (and return () if it cannot rewrite it back).  A working
                   default implementation is provided.

           nathelper
                   Optional Net::SIP::NATHelper::* object. When given it will be used to do NAT,
                   e.g. if the incoming and outgoing legs are different it will rewrite the SDP
                   bodies to use local sockets and the nathelper will transfer the RTP data
                   between the local and the original sockets.

           force_rewrite
                   Usually the contact header will only be rewritten, if the incoming and
                   outgoing leg are different. With this option one can force the rewrite, even
                   if they are the same.

METHODS

       receive ( PACKET, LEG, FROM )
           PACKET is the incoming packet, LEG is the Net::SIP::Leg where the packet arrived and
           FROM is the "ip:port" of the sender.

           Called from the dispatcher on incoming packets. The packet will be rewritten ("Via"
           and "Record-Route" headers added, Contact modified) and then the packet will be
           forwarded.

           For requests it can determine the target of the forwarded packet by looking at the
           route or if no route it looks at the URI. For responses it looks at the next Via
           header.

       do_nat ( PACKET, INCOMING_LEG, OUTGOING_LEG )
           This will be called from receive while forwarding data.  If nathelper is defined it
           will be used to rewrite SDP bodies and update nathelpers internal states to forward
           RTP data.

           Return values are like forward_outgoing in Net::SIP::Leg, e.g.  it will return
           "[code,text]" on error or "()" on success, where success can be that the packet was
           rewritten or that there was no need to touch it.

UNDOCUMENTED METHODS

       idside2hash