Socat – Netcat on steroids
Switchboard
Netcat is the Swiss Army knife of networking for admins. Socat takes this principle one step further, offering multiplexing, TLS-secured channels, pipes, Unix sockets, and executables.
Netcat is undoubtedly a useful tool for testing TCP connections or UDP ports, transferring files, and far more [1]. Socat [2] offers even more: Besides raw TCP and UDP connections, it supports channels secured by TLS and can access pipes, Unix sockets, and executables. As if that were not enough, it can also multiplex multiple client connections.
Just like Netcat, Socat expects two position parameters to establish a connection between two network addresses: socat <address1> <address2>. It can make sense to transfer files via raw TCP connections, for example, if you need to work as a different user on the target system than on the source. On many of the systems I support, sudo I/O logging is enabled.
This means that for SCP or SFTP transfers with a user change (Listing 1), the complete transfer is added to the sudo logs via stdin and stdout. This can mean several gigabytes of data need to be stored in the /var/log/sudo/ directory. If you don't want to do without additional security via public key authentication and deactivated root accounts, you have to come up with something smart for transfers of this type. This is where Netcat and Socat come into play.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Digital Autonomy
• The Answer Was Already on the Shelf
• Changing the Chip Industry: How Public Investment Has Grown Open Silicon
• United Nations Open Source Portal Goes Live
• EU Open Source Strategy Plays Key Role in Tech Sovereignty Package
• France Says “Au Revoir” to Microsoft
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Dutch Government Turns to Open Source for Digital Sovereignty
Following in the footsteps of European countries, the Netherlands is looking to increase its sovereign digital infrastructure with open source software.
-
Linux May Soon Work on Snapdragon X2-Based PCs
If you're thinking about buying a Snapdragon X2-based desktop or laptop, Linux may soon be an option.
-
KDE for People Initiative Calls for AI Ban in Plasma
A new community of KDE wants the project to adopt a strict no-AI policy for KDE Plasma.
-
KDE Sets Ambitious Goals for 2026 and Beyond
KDE Connect reveals the goals for the Linux desktop darling, with one of those goals long overdue.
-
It’s Time to Test Fedora 45 Beta
Fedora 45 beta has been released with updated Gnome, KDE Plasma, and kernel.
-
Ubuntu Stonking Stingray Gets Even Rustier
Ubuntu 26.10 has completed its migration to the Rust-based coreutils.
-
AI Fixes Linux Bottlenecks Using “Hideous” Code
A Linux developer used AI to fix bottlenecks that caused problems when building the kernel. The resulting AI-generated code needed a lot of work.
-
Advanced Video Coding Still Under Patent
Brazilian patent BRPI0109962B1 has expired, which means that DivX and Xvid are no longer problematic for Linux, but it doesn’t mean that video is all of a sudden fully unleashed.
-
2,000 Vulnerabilities per Linux Release
Thanks to AI bug hunters, the Linux kernel is seeing record numbers of vulnerabilities, and it's overwhelming developers.
-
Linux Exempt from California’s Age Verification Law
So long as Linux is distributed under the GPL, MIT, BSD, and Apache licenses, the OS is exempt from being required to verify the age of its users in California.