netcat
![]() The netcat command | |
Original author(s) | *Hobbit* |
---|---|
Developer(s) | Avian Research |
Initial release | October 28, 1995[1] |
Final release | 1.10
/ March 1996 |
Website | nc110 |
netcat (often abbreviated to nc) is a computer networking utility for reading from and writing to network connections using
It is able to perform port scanning, file transferring and port listening.
Features
The original netcat's features include:[2]
- Outbound or inbound connections, TCP or UDP, to or from any ports
- Full DNS forward/reverse checking, with appropriate warnings
- Ability to use any local source port
- Ability to use any locally configured network source address
- Built-in port-scanning capabilities, with randomization
- Built-in loose source-routing capability
- Can read command line arguments from standard input
- Slow-send mode, one line every N seconds
- Hex dump of transmitted and received data
- Optional ability to let another program service establish connections
- Optional telnet-options responder
Rewrites like GNU's and OpenBSD's support additional features. For example, OpenBSD's nc supports TLS, and GNU netcat natively supports a tunneling mode supporting UDP and TCP (optionally allowing one to be tunneled over the other) in a single command,[3] where other versions may require piping data from one netcat instance to another.
Ports and reimplementations
The original version of netcat was a Unix program. The last version (1.10) was released in March 1996.[4]
There are several implementations on POSIX systems, including rewrites from scratch like GNU netcat[5] or OpenBSD netcat,[6] the latter of which supports IPv6 and TLS. The OpenBSD version has been ported to the FreeBSD base,[7] Windows/Cygwin,[8] and Linux.[9] Mac OS X comes with netcat installed as of OSX 10.13 or users can use MacPorts to install a variant.[10]
A DOS version of netcat called NTOOL is included in the FreeDOS Package group Networking.[11] It is based on the WatTCP stack and licensed under the European Union Public Licence Version 1.1.[12]
Known ports for embedded systems includes versions for
BusyBox includes by default a lightweight version of netcat.
Socat
Cryptcat[18] is a version of netcat with integrated transport encryption capabilities.
In the middle of 2005,
On some systems, modified versions or similar netcat utilities go by the command name(s) nc
, ncat
, pnetcat
, socat
, sock
, socket
, sbd
.
ncat
Ncat is a similar tool to netcat provided by Nmap suite.[19] "While Ncat isn't built on any code from the “traditional” Netcat (or any other implementation), Ncat is most definitely based on Netcat in spirit and functionality."[20]
Ncat features includes: ability to chain Ncats together, redirect both TCP and UDP ports to other sites, SSL support, and proxy connections via
See also
- List of Unix commands
- cat (Unix) – Unix command utility
- Nmap
- OpenSSL
- Telnet
- Plink
- Packet Sender
- Banner grabbing
References
- ^ Hobbit (1995-10-28). "New tool available: Netcat". Bugtraq mailing list. Retrieved 2019-06-05.
- ISBN 978-0387954257.
- ^ Giovanni Giacobbi (2006-11-01). "The GNU Netcat project". Retrieved 2020-03-22.
- ^ "Netcat 1.10". nc110.sourceforge.net. 2008-02-14. Retrieved 2019-06-05.
- ^ Giovanni Giacobbi (2006-11-01). "The GNU Netcat project". Retrieved 2019-06-05.
- ^ "OpenBSD CVSWeb: /src/usr.bin/nc/". OpenBSD. Retrieved 2019-06-05.
- ^ delphij (2005-02-06). "Contents of /release/5.4.0/usr.bin/nc/Makefile". FreeBSD. Retrieved 2019-06-05.
- ^ Thomas Linden (2011-03-02). "Netcat OpenBSD Cygwin Port 1.10.2.3". Daemon.de. Retrieved 2019-06-05.
- ^ Debian netcat-openbsd
- ^ "MacPorts Portfiles: netcat". MacPorts. Retrieved 2019-06-05.
- ^ "ibiblio.org FreeDOS Group -- Networking". ibiblio. 2019-03-03. Retrieved 2019-06-05.
- ^ Jürgen Hoffmann (2018-11-03). "various tools". Retrieved 2019-06-05.
- ^ Andreas Bischoff (2010-06-07). "Netcat 4 wince". Retrieved 2019-06-05.
- ^ "Revision 835: /trunk/data/netcat". 2008-08-18. Retrieved 2019-06-05.
- ^ "socat - Multipurpose relay". 2019-04-06. Retrieved 2019-06-05.
- ^ a b "Socat security advisory 7". 2016-02-01. Retrieved 2019-06-05.
- ^ Chirgwin, Richard (2016-02-03). "Socat slams backdoor, sparks thrilling whodunit". The Register. Retrieved 2019-06-05.
- ^ "CryptCat Project". 2005-10-18. Retrieved 2019-06-05.
- ^ a b "Ncat - Netcat for the 21st Century". Nmap. 2009-07-08. Retrieved 2019-06-05.
- ^ "ncat(1) - Ncat Reference Guide". manpages.debian.org. 2016-12-18. Retrieved 2019-06-05.
- ^ "Ncat - Netcat for the 21st Century".
External links
- Official website
- Linux User Commands Manual –