low level networking in python

[Maxim Veksler]

Hello,

I wish to do some low level network stuff using python.

I've googled somewhat and came up with pylibpcap[1], trouble is I
can't compile it on my Ubuntu 6.10 workstation. Can someone please
suggest a way to read some bits from random ports? I'm looking to
write a simple pen-testing tool that would try from one side
connecting to ports and from the other side sniff traffic to see on
what ports traffic is coming.

For pylibpcap I'm getting:

"""
hq4ever@lucky:~/development/personal/pylibpcap/pylibpcap-0.5.1$ python
setup.py build
running build
running build_ext
building '_pcapmodule' extension
swig -python -shadow -ISWIG -o pcap.c pcap.i
pcap.i:72: Warning(124): Specifying the language name in %typemap is
deprecated - use #ifdef SWIG<LANGinstea d.
pcap.i:77: Warning(124): Specifying the language name in %typemap is
deprecated - use #ifdef SWIG<LANGinstea d.
pcap.i:82: Warning(124): Specifying the language name in %typemap is
deprecated - use #ifdef SWIG<LANGinstea d.
/usr/bin/python ./build-tools/docify.py pcap.c
/usr/bin/python ./build-tools/docify-shadow.py pcap.py
Traceback (most recent call last):
File "./build-tools/docify-shadow.py", line 30, in ?
raise 'source file doesn\'t look like swigged shadow class code'
source file doesn't look like swigged shadow class code
error: command '/usr/bin/python' failed with exit status 1
"""

[1] http://pylibpcap.sourceforge.net/
[2] http://py.vaults.ca/apyllo.py/126307487

--
Cheers,
Maxim Veksler

"Free as in Freedom" - Do u GNU ?

[kyosohma@gmail.com]

Re: low level networking in python

On Apr 3, 10:29 am, "Maxim Veksler" <hq4e...@gmail. comwrote:

Hello,
>
I wish to do some low level network stuff using python.
>
I've googled somewhat and came up with pylibpcap[1], trouble is I
can't compile it on my Ubuntu 6.10 workstation. Can someone please
suggest a way to read some bits from random ports? I'm looking to
write a simple pen-testing tool that would try from one side
connecting to ports and from the other side sniff traffic to see on
what ports traffic is coming.
>
For pylibpcap I'm getting:
>
"""
hq4ever@lucky:~/development/personal/pylibpcap/pylibpcap-0.5.1$ python
setup.py build
running build
running build_ext
building '_pcapmodule' extension
swig -python -shadow -ISWIG -o pcap.c pcap.i
pcap.i:72: Warning(124): Specifying the language name in %typemap is
deprecated - use #ifdef SWIG<LANGinstea d.
pcap.i:77: Warning(124): Specifying the language name in %typemap is
deprecated - use #ifdef SWIG<LANGinstea d.
pcap.i:82: Warning(124): Specifying the language name in %typemap is
deprecated - use #ifdef SWIG<LANGinstea d.
/usr/bin/python ./build-tools/docify.py pcap.c
/usr/bin/python ./build-tools/docify-shadow.py pcap.py
Traceback (most recent call last):
File "./build-tools/docify-shadow.py", line 30, in ?
raise 'source file doesn\'t look like swigged shadow class code'
source file doesn't look like swigged shadow class code
error: command '/usr/bin/python' failed with exit status 1
"""
>
[1]http://pylibpcap.sourc eforge.net/
[2]http://py.vaults.ca/apyllo.py/126307487
>
--
Cheers,
Maxim Veksler
>
"Free as in Freedom" - Do u GNU ?

I would assume you could use the socket module. This post details
someone else who opened ports with Python:

http://www.thescripts.com/forum/thread44280.html

Here's another resource using some python servers:

http://docs.python.org/lib/socket-example.html

Finally, a Socket programming howto:

http://www.amk.ca/python/howto/sockets/

I'm also told that the Twisted framework is excellent for this sort of
thing.

Mike

[Steve Holden]

Re: low level networking in python

kyosohma@gmail. com wrote:

On Apr 3, 10:29 am, "Maxim Veksler" <hq4e...@gmail. comwrote:

>Hello,
>>
>I wish to do some low level network stuff using python.
>>
>I've googled somewhat and came up with pylibpcap[1], trouble is I
>can't compile it on my Ubuntu 6.10 workstation. Can someone please
>suggest a way to read some bits from random ports? I'm looking to
>write a simple pen-testing tool that would try from one side
>connecting to ports and from the other side sniff traffic to see on
>what ports traffic is coming.
>>
>For pylibpcap I'm getting:
>>
>"""
>hq4ever@lucky: ~/development/personal/pylibpcap/pylibpcap-0.5.1$ python
>setup.py build
>running build
>running build_ext
>building '_pcapmodule' extension
>swig -python -shadow -ISWIG -o pcap.c pcap.i
>pcap.i:72: Warning(124): Specifying the language name in %typemap is
>deprecated - use #ifdef SWIG<LANGinstea d.
>pcap.i:77: Warning(124): Specifying the language name in %typemap is
>deprecated - use #ifdef SWIG<LANGinstea d.
>pcap.i:82: Warning(124): Specifying the language name in %typemap is
>deprecated - use #ifdef SWIG<LANGinstea d.
>/usr/bin/python ./build-tools/docify.py pcap.c
>/usr/bin/python ./build-tools/docify-shadow.py pcap.py
>Traceback (most recent call last):
> File "./build-tools/docify-shadow.py", line 30, in ?
> raise 'source file doesn\'t look like swigged shadow class code'
>source file doesn't look like swigged shadow class code
>error: command '/usr/bin/python' failed with exit status 1
>"""
>>
>[1]http://pylibpcap.sourc eforge.net/
>[2]http://py.vaults.ca/apyllo.py/126307487
>>
>--
>Cheers,
>Maxim Veksler
>>
>"Free as in Freedom" - Do u GNU ?

>
I would assume you could use the socket module. This post details
someone else who opened ports with Python:
>

http://www.thescripts.com/forum/thread44280.html

>
Here's another resource using some python servers:
>

http://docs.python.org/lib/socket-example.html

>
Finally, a Socket programming howto:

http://www.amk.ca/python/howto/sockets/

>
I'm also told that the Twisted framework is excellent for this sort of
thing.
>

The problem with dealing with ports is that you'd have to open each port
individually. So the OP, I presume, is trying to capture packets
generically as they arrive at a particular point int he processing cycle
to avoid that necessity.

regards
Steve
--
Steve Holden +44 150 684 7255 +1 800 494 3119
Holden Web LLC/Ltd http://www.holdenweb.com
Skype: holdenweb http://del.icio.us/steve.holden
Recent Ramblings http://holdenweb.blogspot.com

[Maxim Veksler]

Re: low level networking in python

On 3 Apr 2007 08:43:57 -0700, kyosohma@gmail. com <kyosohma@gmail .comwrote:

On Apr 3, 10:29 am, "Maxim Veksler" <hq4e...@gmail. comwrote:

Hello,

I wish to do some low level network stuff using python.

--
Cheers,
Maxim Veksler

"Free as in Freedom" - Do u GNU ?

>
I would assume you could use the socket module. This post details
someone else who opened ports with Python:
>

http://www.thescripts.com/forum/thread44280.html

>
Here's another resource using some python servers:
>

http://docs.python.org/lib/socket-example.html

>
Finally, a Socket programming howto:

http://www.amk.ca/python/howto/sockets/

>
I'm also told that the Twisted framework is excellent for this sort of
thing.
>

Thanks for the heads-up. The sockets howto was great help.

I'm trying to bind a non-blocking socket, here is my code:
"""
#!/usr/bin/env python

import socket, select
from time import sleep

s_nb10000 = socket.socket(s ocket.AF_INET, socket.SOCK_STR EAM)
s_nb10000.setbl ocking(0)

s_nb10000.bind( ('192.168.2.106 ', 10002))
s_nb10000.liste n(5)

while 1:
conn, addr = s_nb10000.accep t()
ready_to_read, ready_to_write, in_error = select.select([conn], [], [], 0)
print (ready_to_read, ready_to_write, in_error)
sleep(100)

s_nb10000.close ()
"""

And this is the exception I'm getting:
"""
python non_blocking_so cket.py
Traceback (most recent call last):
File "non_blocking_s ocket.py", line 13, in ?
conn, addr = s_nb10000.accep t()
File "/usr/lib/python2.4/socket.py", line 161, in accept
sock, addr = self._sock.acce pt()
socket.error: (11, 'Resource temporarily unavailable')
"""

What am I doing wrong here?

p.s.
I've looked at twisted before posting this post. I've seen they
impelement alot of application level protocols but I didn't see much
treatment for low level "raw" network data, not to mention that it's a
way way over kill for what I'm asking to achieve. Twisted does have a
subproject called "Twisted Pair: Low-level networking" but sadly it's
unmaintained and undocumented.

Mike
>

Maxim.


--
Cheers,
Maxim Veksler

"Free as in Freedom" - Do u GNU ?

[Irmen de Jong]

Re: low level networking in python

Maxim Veksler wrote:

I'm trying to bind a non-blocking socket, here is my code:
"""
#!/usr/bin/env python
>
import socket, select
from time import sleep
>
s_nb10000 = socket.socket(s ocket.AF_INET, socket.SOCK_STR EAM)
s_nb10000.setbl ocking(0)
>
s_nb10000.bind( ('192.168.2.106 ', 10002))
s_nb10000.liste n(5)
>
while 1:
conn, addr = s_nb10000.accep t()
ready_to_read, ready_to_write, in_error = select.select([conn], [],
[], 0)
print (ready_to_read, ready_to_write, in_error)
sleep(100)
>
s_nb10000.close ()
"""
>
And this is the exception I'm getting:
"""
python non_blocking_so cket.py
Traceback (most recent call last):
File "non_blocking_s ocket.py", line 13, in ?
conn, addr = s_nb10000.accep t()
File "/usr/lib/python2.4/socket.py", line 161, in accept
sock, addr = self._sock.acce pt()
socket.error: (11, 'Resource temporarily unavailable')
"""
>
What am I doing wrong here?

Nothing.
Any operation on a non-blocking socket that is usually blocking
(this includes accept(), bind(), connect(), recv with MSG_WAITALL)
can possibly return a socket.error with errno set to EAGAIN.
('resource temporarily unavailable').
If this happens you should use a select() on the socket to
wait until it's done with the requested operation.

--Irmen

>
p.s.
I've looked at twisted before posting this post. I've seen they
impelement alot of application level protocols but I didn't see much
treatment for low level "raw" network data, not to mention that it's a
way way over kill for what I'm asking to achieve. Twisted does have a
subproject called "Twisted Pair: Low-level networking" but sadly it's
unmaintained and undocumented.
>

>Mike
>>

>
Maxim.
>
>

[billiejoex]

Re: low level networking in python

I wish to do some low level network stuff using python.

I've googled somewhat and came up with pylibpcap[1], trouble is I
can't compile it on my Ubuntu 6.10 workstation.

I would suggest pcapy:
http://oss.coresecurity.com/projects/pcapy.html
Higher level, easier Object-Oriented API and support for multi-
threading.
Here's an example showing a simple sniffer app:
http://oss.coresecurity.com/impacket/sniff.py
Anyway, what kind of 'low-level network stuff' we're talking about?

[Maxim Veksler]

Re: low level networking in python

On 4/4/07, Irmen de Jong <irmen.NOSPAM@x s4all.nlwrote:

Maxim Veksler wrote:
>

I'm trying to bind a non-blocking socket, here is my code:
"""
#!/usr/bin/env python

import socket, select
from time import sleep

s_nb10000 = socket.socket(s ocket.AF_INET, socket.SOCK_STR EAM)
s_nb10000.setbl ocking(0)

s_nb10000.bind( ('192.168.2.106 ', 10002))
s_nb10000.liste n(5)

while 1:
conn, addr = s_nb10000.accep t()
ready_to_read, ready_to_write, in_error = select.select([conn], [],
[], 0)
print (ready_to_read, ready_to_write, in_error)
sleep(100)

s_nb10000.close ()
"""

And this is the exception I'm getting:
"""
python non_blocking_so cket.py
Traceback (most recent call last):
File "non_blocking_s ocket.py", line 13, in ?
conn, addr = s_nb10000.accep t()
File "/usr/lib/python2.4/socket.py", line 161, in accept
sock, addr = self._sock.acce pt()
socket.error: (11, 'Resource temporarily unavailable')
"""

What am I doing wrong here?

>
Nothing.
Any operation on a non-blocking socket that is usually blocking
(this includes accept(), bind(), connect(), recv with MSG_WAITALL)
can possibly return a socket.error with errno set to EAGAIN.
('resource temporarily unavailable').
If this happens you should use a select() on the socket to
wait until it's done with the requested operation.
>

Hello everyone, I would like to thank you all for the helping tips so
far, with your help I managed to improve the previous code to not give
the error, I believe it's now working.

The non blocking echo socket code:
"""
#!/usr/bin/env python

import socket, select

s_nb10000 = socket.socket(s ocket.AF_INET, socket.SOCK_STR EAM)
s_nb10000.setbl ocking(0)

s_nb10000.bind( ('0.0.0.0', 10002))
s_nb10000.liste n(5)

while 1:
ready_to_read, ready_to_write, in_error =
select.select([s_nb10000], [], [], 0)
if s_nb10000 in ready_to_read:
conn, addr = s_nb10000.accep t()
while 1:
data = conn.recv(1024)
if not data: break
conn.send(data)
conn.close()

s_nb10000.close ()
"""

--Irmen
>

Maxim.


--
Cheers,
Maxim Veksler

"Free as in Freedom" - Do u GNU ?