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Simplest port scanner

Terminal - Simplest port scanner
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
4
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.

Alternatives

There are 4 alternatives - vote for the best!

Terminal - Alternatives

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What others think

Stolen but cool.

#10: Bash Socket Programming

http://www.cyberciti.biz/tips/spice-up-your-unix-linux-shell-scripts.html

Comment by meathive 235 weeks and 3 days ago

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