How to route all traffic through a proxy

Method 1

Use socksify-me.

Method 2 (deprecated)

Attention! Everything has been tested only on the ArchLinux distribution! It is possible that the commands will be different.

First, we need to supply some packages:

$ sudo pacman -S nftables iptables-nft firewalld

and redsocks from the AUR:

$ git clone https://aur.archlinux.org/redsocks.git
$ cd redsocks
$ makepkg -sric

Next, we need to change the redsocks config and bring it to this form:

base {
 log_debug = on;
 log_info = on;
 log = "stderr";
 daemon = off;
 redirector = iptables;
}
redsocks {
    // Local IP listen to
    local_ip = 127.0.0.1;
    // Port to listen to
    local_port = 1081;
    // Remote proxy address
    ip = 127.0.0.1;
    port = YOUR_SOCKS5_LOCAL_PORT;
    // Proxy type
    type = socks5;
}

You need to change "YOUR_SOCKS5_LOCAL_PORT" to your value.

Save the config and turn on firewalld and redsocks services:

$ sudo systemctl enable --now firewalld.service redsocks.service

Now we need to configure firewalld to route traffic on port 1081:

$ sudo firewall-cmd --direct --add-chain ipv4 nat REDSOCKS

$ sudo firewall-cmd --direct --add-rule ipv4 nat REDSOCKS 0 -d 0.0.0.0/8 -j RETURN
$ sudo firewall-cmd --direct --add-rule ipv4 nat REDSOCKS 0 -d 10.0.0.0/8 -j RETURN
$ sudo firewall-cmd --direct --add-rule ipv4 nat REDSOCKS 0 -d 127.0.0.0/8 -j RETURN
$ sudo firewall-cmd --direct --add-rule ipv4 nat REDSOCKS 0 -d 169.254.0.0/16 -j RETURN
$ sudo firewall-cmd --direct --add-rule ipv4 nat REDSOCKS 0 -d 172.16.0.0/12 -j RETURN
$ sudo firewall-cmd --direct --add-rule ipv4 nat REDSOCKS 0 -d 192.168.0.0/16 -j RETURN
$ sudo firewall-cmd --direct --add-rule ipv4 nat REDSOCKS 0 -d 224.0.0.0/4 -j RETURN
$ sudo firewall-cmd --direct --add-rule ipv4 nat REDSOCKS 0 -d 240.0.0.0/4 -j RETURN

$ sudo firewall-cmd --direct --add-rule ipv4 nat OUTPUT 0 -p tcp -m owner --uid-owner "UID_OF_USER_WHICH_RUN_PROXY_CLIENT" -j RETURN

$ sudo firewall-cmd --direct --add-rule ipv4 nat REDSOCKS 0 -p tcp -j REDIRECT --to-ports 1081

$ sudo firewall-cmd --direct --add-rule ipv4 nat OUTPUT 0 -p tcp -j REDSOCKS

For example, instead of "UID_OF_USER_WHICH_RUN_PROXY_CLIENT" I wrote 84 - shadowsocks uid.

Now try curl ifconfig.me. If that worked, run:

$ sudo firewall-cmd --runtime-to-permanent

in order to save all changes. Enjoy!