>In some mail from itojun@iijlab.net, sie said:
>> 
>> >One thing I did notice was the packets did not seem to have correct
>> >checksums.  Have I picked the wrong place for intercepting IPv4 packets ?
>> 
>> 	to me bpf_mtap() in the middle of ip_input() seems to be the cause.
>> 
>> >Also, where on earth is the correct place in the KAME IPv6 code to add
>> >similar hooks ?  I had a look but it was not clear where to go..
>> 
>> 	i don't think we should put any bpf_mtap() into ip*_input().  it
>> 	belongs to layer 2, not layer 3.
>
>Do you have a better solution ?

	the best to perform bpf_mtap() is right before IF_ENQUEUE() in
	esp[46]_input().

itojun