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IPForward ClassifyFn not called(NAT) RRS feed

  • Question

  • Hello,

    In our NAT project, I used the IPForward layer to forward private packet to public.

    So I register a callout for FWPM_LAYER_IPFORWARD_V4 layer, nothing entry my forward callout(I use KdPrint to test). but other layer (e.g. FWPM_LAYER_INBOUND_IPPACKET_V4) not appears the same problem

    My codes step:

    1. add sub-layers

    2. register callout

    3. add filters

    Thanks

    Sunday, March 9, 2014 8:21 AM

All replies

  • I found the 
    <p>FWPM_CONDITION_ALE_PROMISCUOUS_MODE in ALE resource assignment.</p><p>If the NIC not open the promiscuous mode, could I receive packet in IP Forward layer?</p><p>In my test, I not found any packets, because my ipforward classifyfn not called.</p><p></p><p>Anyone help me.</p><p></p><p>Thanks</p>
    
    Sunday, March 9, 2014 11:01 AM
  • Can you specify what the filter looks like (i.e. what conditions are you using). What does the traffic look like that you expect to hit your callout ( Src Address, Dst Address, etc)

    Thanks,


    Dusty Harper [MSFT]
    Microsoft Corporation
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    This posting is provided "AS IS", with NO warranties and confers NO rights
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    Tuesday, March 18, 2014 9:01 PM
    Moderator
  • That's true. I have met the same problem, I register a callout in FWPM_LAYER_IPFORWARD_V4 layer, the condition is NULL (as the DDK said, that's means always ture), but my classifyfn was never got called. And I'm sure there is some packets should be forwarded at that time (by wireshark, some packets received which destination IP is different between the current NIC's IP). But after I modify the callout layer to FWPM_LAYER_INBOUND_IPPACKET_V4, my classifyfn was got called with those packets.
    Monday, October 13, 2014 3:18 AM