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Commands tagged socket

Commands tagged socket from sorted by
Terminal - Commands tagged socket - 4 results
for p in {1..1023}; do(echo >/dev/tcp/localhost/$p) >/dev/null 2>&1 && echo "$p open"; done
2010-04-26 18:09:22
User: benyounes
Functions: echo
Tags: scanner socket
4
Up
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Simplest port scanner

Very handy way to perform a host scan if you don't have nmap,ncat,nc ...or other tools installed locally.

When executing a command on a /dev/tcp/$host/$port pseudo-device file, Bash opens a TCP connection to the associated socket and UDP connection when using /dev/udp/$host/$port.A simlpe way to get servers banner is to run this command "cat < /dev/tcp/localhost/25" , here you will get mail server's banner.

NOTE: Bash, as packaged for Debian, does not support using the /dev/tcp and /dev/udp pseudo-device it's not enabled by default Because bash in Debian is compiled with ?disable-net-redirections.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
python -c 'import socket; s = socket.socket(socket.AF_INET, socket.SOCK_STREAM); s.connect(("<hostname>", <port>)); print s.getsockname()[0] ; s.close() ;' 2> /dev/null
2009-10-13 16:21:15
User: angleto
Functions: python
Tags: python networking tcp socket
1
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retrieve the source address used to contact a given host

on multihomed hosts, connected to several networks, could be usefull to know the source address (local ip address) used to reach the target host, this command does not require root priviledges.

The command use a TCP socket, if there is any error the command return an empty string, elsewhere return a valid ip address.

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo foo | netcat 192.168.1.2 25
2009-09-13 01:33:02
User: pykler
Functions: echo
Tags: Network udp tcp icmp protocol socket
2
Up
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send echo to socket network

Using netcat, usuallly installed on debian/ubuntu.

Also to test against a sample server the following two commands may help

echo got milk? | netcat -l -p 25

python -c "import SocketServer; SocketServer.BaseRequestHandler.handle = lambda self: self.request.send('got milk?\n'); SocketServer.TCPServer(('0.0.0.0', 25), SocketServer.BaseRequestHandler).serve_forever()"

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echo "foo" > /dev/tcp/192.168.1.2/25
2009-09-12 16:48:05
User: mobidyc
Functions: echo
Tags: Network udp tcp icmp protocol socket
22
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send echo to socket network

this command will send a message to the socket 25 on host 192.168.1.2 in tcp.

works on udp and icmp

understand only IP address, not hostname.

on the other side (192.168.1.2), you can listen to this socket and test if you receive the message.

easy to diagnose a firewall problem or not.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate