Package net.i2p.router.tunnel

Class TunnelDispatcher

java.lang.Object
net.i2p.router.tunnel.TunnelDispatcher
All Implemented Interfaces:
Service
public class TunnelDispatcher extends Object implements Service
Handle the actual processing and forwarding of messages through the various tunnels. 
  For each type of tunnel, it creates a chain of handlers, as follows:

  Following tunnels are created by us:

    Outbound Gateway > 0 hops:
       PumpedTunnelGateway
         BatchedRouterPreprocessor -> OutboundSender -> OutboundReceiver -> OutNetMessagePool

    Outbound zero-hop Gateway+Endpoint:
       TunnelGatewayZeroHop
         OutboundMessageDistributor -> OutNetMessagePool

    Inbound Endpoint > 0 hops:
       TunnelParticipant
        RouterFragmentHandler ->  InboundEndpointProcessor -> InboundMessageDistributor -> InNetMessagePool

    Inbound zero-hop Gateway+Endpoint:
       TunnelGatewayZeroHop
         InboundMessageDistributor -> InNetMessagePool


  Following tunnels are NOT created by us:

    Participant (not gateway or endpoint)
       TunnelParticipant
         HopProcessor -> OutNetMessagePool

    Outbound Endpoint > 0 hops:
       OutboundTunnelEndpoint
         RouterFragmentHandler -> HopProcessor -> OutboundMessageDistributor -> OutNetMessagePool

    Inbound Gateway > 0 hops:
       ThrottledPumpedTunnelGateway
         BatchedRouterPreprocessor -> InboundSender -> InboundGatewayReceiver -> OutNetMessagePool

  • Constructor Details

    • TunnelDispatcher

      public TunnelDispatcher(RouterContext ctx)
      Creates a new instance of TunnelDispatcher

  • Method Details

    • joinOutbound

      public boolean joinOutbound(PooledTunnelCreatorConfig cfg)
      We are the outbound gateway - we created this tunnel
      Returns:
      success; false if Tunnel ID is a duplicate

    • joinInbound

      public boolean joinInbound(TunnelCreatorConfig cfg)
      We are the inbound endpoint - we created this tunnel
      Returns:
      success; false if Tunnel ID is a duplicate

    • joinParticipant

      public boolean joinParticipant(HopConfig cfg)
      We are a participant in this tunnel, but not as the endpoint or gateway
      Returns:
      success; false if Tunnel ID is a duplicate

    • joinOutboundEndpoint

      public boolean joinOutboundEndpoint(HopConfig cfg)
      We are the outbound endpoint in this tunnel, and did not create it
      Returns:
      success; false if Tunnel ID is a duplicate

    • joinInboundGateway

      public boolean joinInboundGateway(HopConfig cfg)
      We are the inbound gateway in this tunnel, and did not create it
      Returns:
      success; false if Tunnel ID is a duplicate

    • getParticipatingCount

      public int getParticipatingCount()

    • getNewOBGWID

      public TunnelId getNewOBGWID()
      Get a new random send tunnel ID that isn't a dup. Note that we do not keep track of IDs for pending builds so this does not fully prevent joinOutbound() from failing later.
      Since:
      0.9.5

    • getNewIBEPID

      public TunnelId getNewIBEPID()
      Get a new random receive tunnel ID that isn't a dup. Not for zero hop tunnels. Note that we do not keep track of IDs for pending builds so this does not fully prevent joinInbound() from failing later.
      Since:
      0.9.5

    • getNewIBZeroHopID

      public TunnelId getNewIBZeroHopID()
      Get a new random receive tunnel ID that isn't a dup. For zero hop tunnels only. Note that we do not keep track of IDs for pending builds so this does not fully prevent joinInbound() from failing later.
      Since:
      0.9.5

    • getLastParticipatingExpiration

      public long getLastParticipatingExpiration()
      what is the date/time on which the last non-locally-created tunnel expires?

    • remove

      public void remove(TunnelCreatorConfig cfg)
      We no longer want to participate in this tunnel that we created

    • remove

      public void remove(HopConfig cfg)
      No longer participate in the tunnel that someone asked us to be a member of

    • dispatch

      public void dispatch(TunnelDataMessage msg, Hash recvFrom)
      We are participating in a tunnel (perhaps we're even the endpoint), so take the message and do what it says. If there are later hops, that means encrypt a layer and forward it on. If there aren't later hops, how we handle it depends upon whether we created it or not. If we didn't, simply honor the instructions. If we did, unwrap all the layers of encryption and honor those instructions (within reason).

    • dispatch

      public void dispatch(TunnelGatewayMessage msg)
      We are the inbound tunnel gateway, so encrypt it as necessary and forward it on.

    • dispatchOutbound

      public void dispatchOutbound(I2NPMessage msg, TunnelId outboundTunnel, Hash targetPeer)
      We are the outbound tunnel gateway (we created it), so wrap up this message with instructions to be forwarded to the targetPeer when it reaches the endpoint.
      Parameters:
      msg - raw message to deliver to the target peer
      outboundTunnel - tunnel to send the message out, or null for direct
      targetPeer - peer to receive the message

    • dispatchOutbound

      public void dispatchOutbound(I2NPMessage msg, TunnelId outboundTunnel, TunnelId targetTunnel, Hash targetPeer)
      We are the outbound tunnel gateway (we created it), so wrap up this message with instructions to be forwarded to the targetTunnel on the targetPeer when it reaches the endpoint.
      Parameters:
      msg - raw message to deliver to the targetTunnel on the targetPeer
      outboundTunnel - tunnel to send the message out
      targetTunnel - tunnel on the targetPeer to deliver the message to, or null for direct
      targetPeer - gateway to the tunnel to receive the message

    • listParticipatingTunnels

      public List<HopConfig> listParticipatingTunnels()
      Only for console TunnelRenderer.
      Returns:
      a copy

    • updateParticipatingStats

      public void updateParticipatingStats(int ms)
      Generate a current estimate of usage per-participating-tunnel lifetime. The router code calls this every 'ms' millisecs. This is better than waiting until the tunnel expires to update the rate, as we want this to be current because it's an important part of the throttle code. Stay a little conservative by taking the counts only for tunnels 1-10m old and computing the average from that.

    • shouldDropParticipatingMessage

      public boolean shouldDropParticipatingMessage(TunnelDispatcher.Location loc, int type, int length)
      Implement random early discard (RED) to enforce the share bandwidth limit. For now, this does not enforce the available bandwidth, we leave that to Throttle. This is similar to the code in ../RouterThrottleImpl.java We drop in proportion to how far over the limit we are. Perhaps an exponential function would be better? The drop probability is adjusted for the size of the message. At this stage, participants and IBGWs see a standard 1024 byte message. OBEPs however may see a wide variety of sizes. Network-wise, it's most efficient to drop OBEP messages, because they are unfragmented and we know their size. Therefore we drop the big ones and we drop a single wrapped I2CP message, not a fragment of one or more messages. Also, the OBEP is the earliest identifiable hop in the message's path (a plain participant could be earlier or later, but on average is later)
      Parameters:
      loc - message hop location
      type - I2NP message type
      length - the length of the message

    • startup

      public void startup()
      startup
      Specified by:
      startup in interface Service

    • getShareBandwidth

      public static int getShareBandwidth(RouterContext ctx)
      Returns:
      in KBps

    • shutdown

      public void shutdown()
      Description copied from interface: Service
      Instruct the service that the router is shutting down and that it should do whatever is necessary to go down gracefully. It should not depend on other components at this point. This call DOES block.
      Specified by:
      shutdown in interface Service

    • restart

      public void restart()
      Description copied from interface: Service
      Perform a soft restart.
      Specified by:
      restart in interface Service

    • renderStatusHTML

      @Deprecated public void renderStatusHTML(Writer out) throws IOException
      Deprecated.
      moved to router console
      Specified by:
      renderStatusHTML in interface Service
      Throws:
      IOException