ietf
[Top] [All Lists]

Re: TCP/IP

2002-05-27 17:32:06
Dudes, thanks for the book reference. i go to Borders fora copy
myself.

Is it OSI 8 mounth that that eats the osi7 layer buritto, like the
ones you get down in Jose's Burrito Shack.  foot of HMmmmmm good!




---- Original Message ----
From: Valdis(_dot_)Kletnieks(_at_)vt(_dot_)edu
To: billcu(_at_)citynet(_dot_)net
Subject: Re: TCP/IP 
Date: Mon, 27 May 2002 10:38:13 -0400

On Mon, 27 May 2002 09:38:12 EDT, Bill Cunningham 
<billcu(_at_)citynet(_dot_)net>  said:
Win98 is what I use mostly I also have linux. Your right I'd like 
to enter

For Linux, you have the source - go poke around in 
/usr/src/linux/drivers/net
which contains the bottom half of the stack (the device drivers).  
The
top half, which does protocol support, is under /usr/src/linux/net/*.

Please note that from userspace, you want to be using the provided 
syscalls,
as you will most certainly generate an error if you go calling 
kernel code
without a firm understanding of what you're trying to do and why.

I'd certainly stay *FAR* away from any system's TCP stack internals 
until
I had read *and understood* at least the first volume or two of 
Comer's books,
and for Unix/Linux, Steven's "Unix Network Programming".  If you 
don't
recognize those 2 references, you're not ready. ;)

I think you're getting confused by terminology - although many 
programs
have their function entry points on a "stack", which is vulnerable to
tweaking by buffer overflows and other malware, the entire networking
subsystem is *also* referred to as a "stack" (which makes sense once 
you
understand the basics of the OSI 7-layer burrito^H^H^H^H^Hmodel).  
As such,
the networking code doesn't really *HAVE* a distinct entry point - 
it's being
called many ways for different things - from userspace via the 
syscall
interface (to open/bind/send/receive/close a connection), to/from 
device
drivers to receive packets and queue packets for transmission, hooks 
into
the system timing services for callbacks to maintain retransmit 
timers,
and so on.

-- 
                              Valdis Kletnieks
                              Computer Systems Senior Engineer
                              Virginia Tech





<Prev in Thread] Current Thread [Next in Thread>