[Tutor] packet parsing
Thu, 28 Feb 2002 15:16:13 -0600
Remco Gerlich(email@example.com)@2002.02.28 21:57:19 +0000:
> On 0, firstname.lastname@example.org wrote:
> > My second question is: how do I look at/manipulate bytes of an incoming
> > network packet? Or bits even. Right now, I have the following piece of
> > code that receives the SSH server's initial key exchange packet:
> > kexrecv = mysock.recv(blocksize)
> > I want to directly manipulate the bits/bytes of kexrecv. Everything
> > that I've done makes kexrecv into a string. And I'm having problems
> > with kexrecv as a string -- I want to deal with it as a binary stream.
> The string *is* the binary stream. A string is just a bunch of bytes.
That's what I thought. But "print kexrecv" returns nothing in the
interpreter. I just get ">>>" back. "print kexrecv.capitalize()"
returns nothing. "kexrecv.capitalize()" returns a repr() type value
> kexrecv is a string of length 632.
> `kexrecv` is its text representation, in a way that it could be a python
> literal - that means that say a zero byte is one character in the string
> itself, but '\x00' in the repr - three bytes longer. Try playing around with
> the string (and small parts of it) a bit more in the interpreter to get the
OK, that makes sense. But how do I peel of individual bytes? (I just
played with lstrip and am not having any luck -- but this is probably my
lack of knowledge).
So `kexrecv` is the text value. While kexrecv types as a string, I
can't seem to manipulate it as a string. It keeps returning nothing but
> I don't have more time atm to reply carefully to your other comments, this
> is just a quick post.
Thanks for your time.