[ python-Feature Requests-889544 ] win32 raw socket support

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Feature Requests item #889544, was opened at 2004-02-03 08:15
Message generated for change (Settings changed) made by jesko-rs
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Category: Windows
Group: None
Status: Open
>Resolution: Works For Me
Priority: 5
Submitted By: Jesko Huettenhain (jesko-rs)
Assigned to: Nobody/Anonymous (nobody)
Summary: win32 raw socket support

Initial Comment:
I already programmed several tools in Windows that 
make use of raw sockets as Windows NT 5.0 and later 
OS (those include 2k and XP) support raw sockets in the 
Winsock 2 API. I used C/C++ for programming them 
mainly, but I figured python had the better builtin tools 
for building custom packets. However, I witnessed 
several problems when trying to create and use raw 
sockets in Python (Version 2.3, Windows interpreter): 
The raw socket was created, but the IP_HDRINCL 
option, for instance, could not be set once the socket 
was bound. This one and similar problems were indicating 
that the raw sockets implementation was either 
unavailable or had some strange bug.

After I had tried to find the problem in socketmodule.c 
for a while, I realized the problem was not the code, it 
was the library that had been linked with _socket.pyd. It 
looks like _socket.pyd links to wsock32.dll by default, 
which is the DLL that implements Winsock 1 for 32-bit 
windows. However, it should link to ws2_32.dll to provide 
access to the more up-to-date Winsock 2 API. The fix I 
suggest is fairly simple. The key is the WSAStartup() 
function which will let you use the Winsock2 API if it is 
available or use Winsock1 if Winsock2 is not available. 
For this purpose, I link using ws2_32.lib as recommended 
by MSDN and call WSAStartup() by requesting a Winsock 
Version of 2.0. MSDN says that if Winsock 2.0 is 
unavailable, the call will succeed and the Winsock 1 DLL 
will be used.

This fix works pretty well on my Windows 2k machine - I 
am unfortunately not able to test it on other machines 
as well. While messing with the problem, I got a lot of 
help from Matt Cowles [matt at mondoinfo.com] and he 
also suggested that I should post this request here, so 
that's what I am doing.

by_the_way:
As I was already messing with the _socket.pyd dll 
directly, I also added a new member function for python 
sockets called ioctl() to manually ioctl() the socket. 
Moreover, I added the integer constants IP_HDRINCL 
and SIO_RCVALL to be defined always, so that this code 
works and provides pretty satisfying results on my Win2k 
box (a simple sniffer):

from socket import *
s = socket(AF_INET,SOCK_RAW,IPPROTO_RAW)
s.bind((gethostbyname(gethostname()),0))
s.setsockopt(IPPROTO_IP,IP_HDRINCL,1)
s.ioctl(SIO_RCVALL,1)
while(1): print s.recvfrom(4000)[0],"\n------------"

The files I changed (including socket.py with the new 
ioctl function) can be found at:

http://rs.fromadia.com/pysockraw/

It would be very kind if the next version of the Python 
interpreter for windows would include this feature by 
default as it would allow developers like me to build 
python tools that make use of raw sockets in 
Windows ... I can see not many developers are 
interested in this particular feature, but more support is 
better than less support.


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