Re: Connecting to different services with source port 53

Hey,

> Is there a way, how I can establish a connection using source port 53?

Actually, there are a lot of ways to accomplish this task: good old netcat
and iptables SNAT on POSTROUTING are only a couple of examples... You can
also take a look at proxed.c, a small TCP stream redirector/manipulator
written by awgn:

http://awgn.antifork.org/codes/proxed.c

root_at_voodoo:~# ./proxed -h
Usage: proxed [OPTION]...
 SOCKET
   -c int Set SO_RCVBUF size
   -f int Set SO_SNDBUF size
   -y int Set SO_RCVLOWAT size
   -z int Set SO_RCVLOWAT size
   -k Set SO_KEEPALIVE
   -r Set SO_DONTROUTE
 IP
   -A Set TTL ramping assault
   -T ttl Set IP_TTL
   -O tos Set IP_TOS
 TCP
   -x int Set TCP_MAXSEG. Maximum segment size < MTU
   -n Set TCP_NODELAY. Disable Nagle algorithm
   -6 Use IPv6 addresses
   -s [host|any][:.]port Source host and port to listen on
   -d host:port Destination host and port to connect to
   -b [host|any][:.]port Local host and port to bind
 Common
   -V Verbose; display verbose messages.
   -Q N. max of clients; default 10.
   -v Display version number.
   -h Print this help

This network utility may also turn out to be (at least in part) useful to
Mr. Rajeev Kapoor, who asked for something like that 2-3 weeks ago on this
mailing list.

Cheers,

-- 
Marco Ivaldi
Antifork Research, Inc.   http://0xdeadbeef.info/
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