hiho@ll

for learning purpose i need a library which is able to implement the TCP/IP protocol

what i want:
a library which uses raw sockets which i can use to send TCP/IP packets (and upper level packets, but that's not the main goal of the library)
i want to define when which packet should be sent
i'm more interessted in the packet flow than of the parts a packet consists of

i know libnet and libpcap but afaik these libs only implement a better API for raw sockets
i have to implement the ip protocol and the tcp protcol by myself
and i don't want to read the RFC for this
i only want to control
"now the TCP Connection ACK" should be sent
or
"send a TCP FIN Request"
such stuff

thx@ll

AFAIK you have raw sockets and BSD sockets (that's more or less one, but...) and no interface in between. It means that you need to use raw sockets, in your case. The thing is that you want certain parts of the stack,
but not all.

From the things you mentioned, you can emulate them using BSD sockets (FIN after close and so on) and using iptables in a creative way (with passing packets to user space). It looks that's not all you need to do. When you come to IP level, it becomes much more complicated.

Different algorithms come into play. "Send FIN" is not that simple, FIN can look in many different ways depending on the implementation methods, options used and so on.

I don't know what's the purpose, but it looks to me you'll finish using raw sockets and filling the packets yourself.

thx Mara

seems youre right
i'll have a look at some progs which use libnet and the TCP and IP RFC

thx

I have one thing to write to you before you start writing the code: don't be too ambitious. See how much a 'real' TCP/IP stack weights... Make yours as simple as possible.