Re: understanding TCP-IP interface in linux kernel

will_u_tellmemore wrote:
Hi all,
I am planning to write a kernel module which will sit below tcp and
intercept every incoming and outgoing packet(shud i say segment ?? ).
In order to do that i was taking a look at net/ipv4/tcp* files but the
code does hell lot of things and makes it hard for me to find my way
through it.
C
an somebody point me to correct place from where i should start ??
I havent learnt yet about tcp implementation in linux kernel. by TCP-IP
i mean those 2 protocols and not the complete suite.
Is thr good online documentation explaining this implementation.??

Also what am curios about is :
TCP-IP interface .. so how does TCP layer sends "segment" to IP and
receives sengment from IP. ??

Any help in this regard will be greatly appreciated ...


The module you're intending to write may be already written.

Would you please tell what you're going to do with the intercepted
packets (if it's IP it's a packet, if it's TCP it's a segment).

The iptables module collection is pretty good in intercepting
and mangling the packets. If you nee link-level handling
(e.g. Ethernet), ebtables is the thing.

--

Tauno Voipio
tauno voipio (at) iki fi

.

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