Firewalls/fa

نمای کلّی

اجرای یک دیوارآتش محلی تقریباً همیشه یک تمرین خوب است. حتی زمانی که پشت دیوارآتش شبکه قرار دارید، یک دیوارآتش محلی از شما در برابر تهدیدات داخل شبکه محافظت می کند.

UFW

UFW مخفف Uncomplicated FireWall است و برنامه ای برای مدیریت دیوار‌آتش و فیلتر شبکه است. این یک رابط خط‌فرمان فراهم می کند و هدف آن این است که بدون پیچیدگی و آسان برای استفاده باشد. UFW بسیار ساده‌تر از iptables است و مکان خوبی برای شروع است مگر اینکه نیازهای بسیار تخصصی داشته باشید.

=نصب UFW

می توانید بسته ufw را با استفاده از مدیر بسته مورد علاقه خود یا با دستور زیر نصب کنید:

user $ pamac install ufw COPY TO CLIPBOARD

پس از نصب UFW، باید آن را با استفاده از دستورات زیر شروع کرده و فعال کنید:

user $ sudo systemctl enable ufw.service COPY TO CLIPBOARD

user $ sudo ufw enable COPY TO CLIPBOARD

Adding Rules

To view the current configuration you can use the command ufw status. Here is what it looks like in a new install:

$ sudo ufw status verbose

Status: active
Logging: on (low)
Default: deny (incoming), allow (outgoing), disabled (routed)
New profiles: skip

This indicates that it will block all incoming traffic and allow all outgoing traffic. This is a good starting point for most desktop systems. However, often we will want to allow some incoming traffic. This can be done with the command ufw allow. For example, if we want to allow incoming ssh traffic so we can connect to the machine from other machines on the network we could use the command:

user $ sudo ufw allow ssh COPY TO CLIPBOARD

If we wanted to also tcp connections to a local webserver on a non-standard https port, 8443. We could use the command:

user $ sudo ufw allow in 8443/tcp COPY TO CLIPBOARD

Tip

---

When you don't specify "in" or "out", "in" is assumed

UFW and Applications

You may notice a difference in the above two commands. When we built the rules for ssh we used the name and for https we used the port number, 8443. This is because UFW has a small database of applications it knows the ports for. You can see the list with the command:

user $ sudo ufw app list COPY TO CLIPBOARD

For applications on the list you can add them by name. If you want to review the configuration for one of the applications, you can use the command ufw app info. For example, to the configuration for ssh:

$ sudo ufw app info SSH

Profile: SSH
Title: SSH server
Description: SSH server
 
 
Port:
  22/tcp

Tip

---

When using ufw app the commands are case sensitive but when adding rules they are not

Some additional preconfigured applications can be added by installing the package ufw-extras with your favorite package manager or the command:

user $ pamac install ufw-extras COPY TO CLIPBOARD

Removing Rules

Rules can be removed with the ufw delete command. For example, to delete our 8443 rules we could use the command:

user $ sudo ufw delete allow 8443/tcp COPY TO CLIPBOARD

You can also delete them by number. This is easier if you have a numbered list which you can see with the command:

$ sudo ufw status numbered

Status: active
To                         Action      From
     --                         ------      ----
[ 1] 22                         ALLOW IN    Anywhere
[ 2] 22 (v6)                    ALLOW IN    Anywhere (v6)

Now if we wanted to stop allowing ssh on ipv6 we could use the command:

user $ sudo ufw delete 2 COPY TO CLIPBOARD

GUFW

Prefer to use GUI applications and still want to manage your firewall? No problem. GUFW is a GTK front-end for UFW that aims to make managing a Linux firewall as accessible and easy as possible. It features pre-sets for common ports and p2p applications.

If it is not installed already gufw can be installed from the repos:

user $ pamac install gufw COPY TO CLIPBOARD

It will now be available in the menu as Firewall Configuration or by running gufw directly.

iptables

iptables is included as part of the Linux kernel. iptables is significantly more complicated than using a tool like UFW. As a result, a full tutorial on iptables is beyond the scope of this wiki. Using iptables on Manjaro should be the same for every distribution of Linux so there is plenty of available documentation. Some of this is linked below. Here are some basics to get you started.

To enable loading rules on startup you can use the command:

user $ sudo systemctl enable iptables.service COPY TO CLIPBOARD

This will load the rules from the file /etc/iptables/iptables.rules.

To display the currently loaded rules:

user $ sudo iptables -L COPY TO CLIPBOARD

To save the current rules to a file

user $ sudo sh -c "iptables-save > /etc/iptables/iptables.rules" /etc/iptables/iptables.rules" " aria-disabled="false">COPY TO CLIPBOARD

To load the rules from a file

user $ sudo sh -c "iptables-restore > /etc/iptables/iptables.rules" /etc/iptables/iptables.rules" " aria-disabled="false">COPY TO CLIPBOARD

To allow ssh connections

user $ sudo iptables -A INPUT -p tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT COPY TO CLIPBOARD

user $ sudo iptables -A OUTPUT -p tcp --sport 22 -m conntrack --ctstate ESTABLISHED -j ACCEPT COPY TO CLIPBOARD

See Also

• The Arch Wiki on UFW
• The UFW website
• The GUFW website
• The iptables man page
• The Arch Wiki on iptables
• The Debian Wiki on iptables