Regardless of the operating system we use, surfing the internet always carries a riskIn the same way that it has a large amount of very valuable information, it is riddled with malicious programs that can put our equipment and our personal information at risk.
For this reason, operating systems such as Linux use security programs known as firewalls or firewalls, which provide various levels of protection against harmful files, preventing problems in our computer.
In order to get the most out of these essential programs, you need to know how to handle and configure them, and if you want to know everything you need about firewalls on your computer Linux, continue reading.
What is a firewall and what are the levels of these softwares?
A firewall is digital security software that is responsible for monitoring the incoming and outgoing traffic of a network and that, through a series of configurations, decides which elements found in the network traffic are safe and which must be blocked to prevent threats.
They have served as the first network security barrier for more than 25 years, and have a scale of levels that offer more or less protection, depending on the level you are at. The level of protection for firewalls is divided into four levels.
List of the best firewalls to use in Linux and keep your documents and projects 100% secure
Linux has a wide variety of security implements to protect your network traffic. From tools integrated in the kernel, up to security software with graphical interface, and these are the best firewalls available for Linux at every security level.
Go for it:
First Level: Netfilter
Netfilter is a framework integrated directly into the Linux kernel and enables the operating system to perform automatic network management actions such as traffic monitoring, address translation, tracing and filtering of data packets. Keep in mind that user interaction with Netfilter is limited to providing the API that authorizes the use of other software as an intermediary, so Netfilter works completely independently of the user.
Second level: Iptables / Nftables
Iptables works as a controller for filtering protocols Netfilter that can be activated from command terminal. However, Iptables control codes have complex syntax and only allow one action to be taken per command line.
A graphical example of a command line to modify Netfilter parameters is this:
iptables -t nat -A PREROUTING -p tcp --dport 80 -j DNAT --to-destination 192.167.1.1:80
Fortunately, Iptables is rapidly being displaced by Nftables as a firewall controller, because it does the same job as Iptables in a more fluid way and with a more compact and friendly syntax.
By using this improved tool, the Iptables command would be translated into Nftables like this:
nft add rule ip nat PREROUTING tcp dport 80 counter dnat to 192.167.1.1:80
Level 2.5: Non-graphic front-ends
They are optional use tools that work on top of Nftables and allow the user more control over the configuration of firewall protocols on a Linux computer:
- UFW: is a tool created by Canonical for use on home computers. It was developed for Ubuntu and is included in all its versions.
- APF: is software specially designed for server protection. Its configuration is very informative and is designed to guide the user through the configuration process.
- Shorewall: It consists of a high-level configuration tool for Netfilter. The amount of settings and options available make it complex software to use.
- Uruk: is a simple and small script that works as a configuration tool for Iptables. Offers a wide variety of parameters to control network traffic and packet data permissions
- IPFire: It is one of the most secure and popular firewalls among businesses in the world. It is built to work with Netfilter and can be tuned to function as a firewall, proxy server, or VPN gateway
Third level: graphic front-ends
The tools with graphical interface They are preferred by users who are used to other operating systems, as they allow you to adjust your firewall settings in a familiar way.
They can be used on Iptables / Nftables, or in conjunction with programs like APF:
- GUFW: It is the official graphical interface of UFW, and one of the most popular security software for Linux. It is included natively in many distributions and comes preconfigured with a series of settings for specific applications and services that can be adjusted to the user’s convenience.
- Douane: It is among the most popular firewalls for novice users due to the simplicity of its graphical interface. It offers few configuration options, but it is a more than viable option to keep your operating system safe.
- OpenSnitch: It is a laptop from the popular LittleSnitch for Mac OS, modified in Python and adapted for Linux distributions. It offers total control over the devices that connect to the local network, and its community keeps it in constant development
- Firestarter: It has an internal network traffic monitoring tool that allows real-time monitoring of local network data, it has a simple graphical interface with a wide range of options to configure security
- Guarddog: is a firewall generation and management tool, aimed at the most novice users and those who do not want to deal with complicated Iptables parameters. Offers a graphical interface and a very complete range of security settings
These are the best security tools to complement your firewall in Linux
Even though the firewalls in Linux offer a wide security coverage in network traffic, many times it is necessary to complement this security with an external tool to cover all possible gaps.
These are the best security add-ons for Linux firewalls that will keep your computer completely safe:
Lynis
It is a security auditing tool that It is available in the most popular distributions, such as Ubuntu, Fedora and OpenSUSE. Its function is to carry out complete analyzes of the software installed on the computer to detect security flaws to be corrected.
Rkhunter
It is an application executable through command lines that takes care of verifying the presence of rootkits on our computer, as well as Trojans, malware, backdoors and malicious scripts. It is quite meticulous despite the fact that it can only be run manually.
DML
They are the initials of Linux Malware Detector, also know as Maldet. It is especially useful when it comes to analyze websites that pose a potential threat, as well as in the detection of backdoors, blackmailers and other files of a malicious nature.
OpenVAS
It is a framework that It works as a free-to-use vulnerability scanner for the detection and correction of security flaws in the system. It comes installed by default in distributions such as Kali Linux and works both through the command terminal and through its web interface.
Tiger
It is a tool with an easily expandable modular interface that works as a security auditor and as an intrusion detector. It is available for multiple platforms UNIX and is distributed free of charge under a license GPL.
Learn about the safest and most confidential Linux distributions that you can install on your computer
We now present the distributions with better security options, perfect to install on your Linux computer and keep your files and projects safe from any malicious threat.
Let’s see:
Whonix
It is a Linux distribution focused on the security of user data, through the protection, privacy and anonymity on the internett. It is made up of two images called virtual machines, which consist of a private workstation and a communication channel that works under the network Tor.
Privatix
It is a portable distribution that can be installed on a CD / DVD or configured on a bootable USB stick. It is based on Debian GNU / Linux and designed for the edition and transport of sensitive information, communication encryption and private browsing through the Tor.
Tails
It is based on Debian and designed to preserve anonymity while browsing by filtering all network connections through Tor. Like Privatix, it is designed to be run via USB or installed via CD.
Ipredia OS
It is an operating system that focuses on the communication privacy through data encryption, and in the anonymity of browsing by means of network data encryption. It is compatible with a variety of applications such as emails, torrents and IRC, among many others
Kali Linux
It is entirely designed for the purpose of performing various security tasks such as computer security audit, as well as penetration testing and ethical hacking. It is one of the most secure distributions available for Linux to date.