Netcat - Revision history

Leo at 17:14, 8 September 2022

2022-09-08T17:14:20Z

← Older revision		Revision as of 17:14, 8 September 2022
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	netcat/nc/ncat are utilities that sends and receives data using TCP or UDP.		netcat/nc/ncat are utilities that sends and receives data using TCP or UDP.

	netcat can refer to the following projects. Each implementation has similar functionalities, but the command line options may differ.		When talking about 'netcat', it can refer to the following projects. Each implementation has similar functionalities, but the command line options may differ.

	#GNU <code>netcat</code> (which is symlinked to <code>nc</code> on some Linux systems, leading to confusion)		#GNU <code>netcat</code> (which is symlinked to <code>nc</code> on some Linux systems, leading to confusion)
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	<code>ncat --listen 443 --ssl --ssl-key key.pem --ssl-cert cert.pem</code>		<code>ncat --listen 443 --ssl --ssl-key key.pem --ssl-cert cert.pem</code>
	\|}		\|}
			If you're trying to reverse proxy for a SSL server, you should look at [[socat]].

	== Tasks ==		== Tasks ==
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	* Restrict access to a specific host with <code>--allow $sourceIP</code>.		* Restrict access to a specific host with <code>--allow $sourceIP</code>.

			== See also ==

			* [[Socat]] which can be used to send/receive data through sockets as well as TCP/UDP protocols
	{{Navbox Linux}}		{{Navbox Linux}}
	[[Category:Linux]]		[[Category:Linux]]
	[[Category:Networking]]		[[Category:Networking]]
	[[Category:LinuxUtilities]]		[[Category:LinuxUtilities]]

Leo: Updated categories

2021-12-30T01:33:38Z

Updated categories

← Older revision		Revision as of 01:33, 30 December 2021
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	{{Navbox Linux}}		{{Navbox Linux}}
	[[Category:Linux]]		[[Category:Linux]]
			[[Category:Networking]]
	[[Category:LinuxUtilities]]		[[Category:LinuxUtilities]]

Leo: Added categories and navbox

2021-12-30T01:16:27Z

Added categories and navbox

← Older revision		Revision as of 01:16, 30 December 2021
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	* Enable SSL with <code>--ssl</code>.		* Enable SSL with <code>--ssl</code>.
	* Restrict access to a specific host with <code>--allow $sourceIP</code>.		* Restrict access to a specific host with <code>--allow $sourceIP</code>.

			{{Navbox Linux}}
			[[Category:Linux]]
			[[Category:LinuxUtilities]]

Leo at 21:58, 17 December 2021

2021-12-17T21:58:21Z

← Older revision		Revision as of 21:58, 17 December 2021
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	netcat can refer to the following projects. Each implementation has similar functionalities, but the command line options may differ.		netcat can refer to the following projects. Each implementation has similar functionalities, but the command line options may differ.

	# GNU <code>netcat</code> (which is symlinked to <code>nc</code> on some Linux systems, leading to confusion)		#GNU <code>netcat</code> (which is symlinked to <code>nc</code> on some Linux systems, leading to confusion)
	# OpenBSD <code>nc</code>		#OpenBSD <code>nc</code>
	# Nmap's <code>ncat</code> (which is also symlinked to nc) with lots of features including SSL support and proxy connections.		#Nmap's <code>ncat</code> (which is also symlinked to nc) with lots of features including SSL support and proxy connections.

	== Usage ==		==Usage==
	For the most part, netcat and ncat are very similar. The older OpenBSD nc has less features.		For the most part, netcat and ncat are very similar. The older OpenBSD nc has less features.
	{\| class="wikitable"		{\| class="wikitable"
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	\|}		\|}

	=== SSL with ncat ===		===SSL with ncat===
	ncat allows for creating SSL server or client.		ncat allows for creating SSL server or client.
	{\| class="wikitable"		{\| class="wikitable"
	!		!Description
	!		!Command
	\|-		\|-
	\|Connect to a server using SSL		\|Connect to a server using SSL
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	<code>ncat --listen 443 --ssl --ssl-key key.pem --ssl-cert cert.pem</code>		<code>ncat --listen 443 --ssl --ssl-key key.pem --ssl-cert cert.pem</code>
	\|}		\|}
	<br />
			== Tasks ==

			=== Create a remote shell ===
			With ncat, you can use the --exec option to spawn a program on a new connection.
			{{Highlight
			\| code = hostA# ncat --exec /bin/sh -l 8888

			hostB# ncat hostA 8888
			## Any command you type goes to /bin/sh on hostA
			\| lang = terminal
			}}
			If you want to do this a bit more securely, you can also:

			* Enable SSL with <code>--ssl</code>.
			* Restrict access to a specific host with <code>--allow $sourceIP</code>.

Leo: Initial content

2021-12-17T21:51:54Z

Initial content

New page

netcat/nc/ncat are utilities that sends and receives data using TCP or UDP.

netcat can refer to the following projects. Each implementation has similar functionalities, but the command line options may differ.

# GNU <code>netcat</code> (which is symlinked to <code>nc</code> on some Linux systems, leading to confusion)
# OpenBSD <code>nc</code>
# Nmap's <code>ncat</code> (which is also symlinked to nc) with lots of features including SSL support and proxy connections.

== Usage ==
For the most part, netcat and ncat are very similar. The older OpenBSD nc has less features.
{| class="wikitable"
!
!nc
!netcat
!ncat
|-
|Listen on a port
|<code>nc -l -p $port</code>
|<code>netcat -l $port</code>
|<code>ncat -l -p $port</code>
|-
|Send to a port
|<code>nc $port</code>
|<code>netcat $port</code>
|<code>ncat $port</code>
|-
|Send to a port, using a specific source port
|<code>n/a</code>
|<code>netcat -p $sport $dest $dport</code>
|<code>ncat -p $sport $dest $dport</code>
|}

=== SSL with ncat ===
ncat allows for creating SSL server or client.
{| class="wikitable"
!
!
|-
|Connect to a server using SSL
|<code>ncat -C --ssl <server> 443</code>
|-
|Verify a server's SSL
|<code>ncat -C --ssl-verify <server> 443</code>
|-
|Listen using SSL (auto generated)
|<code>ncat --listen --ssl</code>
|-
|Listen using SSL (manual SSL certs)
|<code>openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365</code>

<code>ncat --listen 443 --ssl --ssl-key key.pem --ssl-cert cert.pem</code>
|}
<br />