A few months ago, I did a drawing of the path of an ip packet in the linux 2.4 kernel, it is not completed but it says what you say in graphical form. I would appreciate any feedback and corrections. The figure is attached in compressed (gzipped) eps format. Cheers, On Wed, Jul 17, 2002 at 11:22:54PM +0200, Bernd Eckenfels wrote: > In article <7B2A7784F4B7F0409947481F3F3FEF8303A070F6@eammlnt051.lmc.ericsson.se> you wrote: > > I would like to know if the cloned sk_buff is really needed, and also what > > is the path used, (how to find it, since it's a maze to try to figure out > > the receiving path, by looking at place where sk_buff are cloned, since I > > don't know the entry function). At least knowing the entry function could > > help a lot. > > For 2.4 see net/core/dev.c:netif_rx(skb) which is called by the network > driver. This will add it to the queue->input_pkt_queue, which is processed > by net_rx_action(), which will call the protocol families receive handlers > eighter directly via the func() method of the protcol or by > deliver_to_old_cones() which does contain the clone. for ip it is > net/ipv4/ip_input.c:ip_rcv() which hands it to ip_rcv_finish() which > distributes it to the ip_local_deliver() for local targets which then passes > it to ip_local_deliver_finish() which calls the ip protocol handler, for > example udp_rcv which looks up the socket and passes it into that. > > Hope this is nearly right, by reading the source. Note, I am not shure with > softirq and stuff, which function is running in the irq or bottom half mode. > > Greetings > Bernd > - > : send the line "unsubscribe linux-net" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Vincent Guffens, CESAME, UCL Value your freedom, or you will lose it, teaches history. "Don't bother us with politics," respond those who don't want to learn. -- Richard M. Stallman
Attachment:
path_packet.eps.gz
Description: path of an ip packet in the linux kernel
