Hi Amit, > hi > > Suppose I use libnet to inject packets into the kernel .. suppose they > are tcp packets with a different src ip and dest ip from my machines ip > .... which netfilter hook can i expect this packet to hit first ... the > NF_IP_LOCAL_OUT or the NF_IP_PRE_ROUTING hook .. ? I think only NF_IP_LOCAL_OUT will be hit. > the netfilter unreliable guides state this > > "The NF_IP_LOCAL_OUT [5] hook is called for locally generated packets. Here > You can see that routing occurs after this hook is called: in fact, the > routing code > is called first (to figure out the source IP address and some IP options), > and called again if the packet is altered" > > Here what do we mean by "locally generated packets", the packets generated > by that machines application (irrespective of what src and dest ip that > packet carries) or the packets that have src_ip== that of this > machine(irrespective of whether they were generated by applications on this > machine or if they are coming from the network ??) As far as I understand, we can not decide whether a packet is locally genereated only based on its src_ip. Those packets pass through SNAT should not be thought of as locally genereated by the machine, since these two kinds of packets pass through different routines in the kernel. Jee > Please explain. > > thanks > Amit > > "DISCLAIMER: This message is proprietary to Hughes Software Systems Limited > (HSS) and is intended solely for the use of the individual to whom it is > addressed. It may contain privileged or confidential information and > should not be circulated or used for any purpose other than for what it is > intended. If you have received this message in error, please notify the > originator immediately. If you are not the intended recipient, you are > notified that you are strictly prohibited from using, copying, altering, or > disclosing the contents of this message. HSS accepts no responsibility for > loss or damage arising from the use of the information transmitted by this > email including damage from virus." > >
