Setting up Squid Proxy on Ubuntu Server with Cloudflare WARP Client

This article is available in French and Bahasa Indonesia.

This article aims to run a Squid Proxy Server and forward all traffic to the Cloudflare WARP Client. This can be convenient if you do not want to install WARP Client on multiple devices or on a device that doesn’t support the WARP client.

To get started, ensure you have an active internet connection and the latest version of Ubuntu Server. In this article, we will be using Ubuntu 22.04 (Jammy Jellyfish).

Installing Cloudflare WARP Client

The first step is to install Cloudflare WARP Client. To do this, you will have to paste in the commands below. (You may also refer to the official cloudflare instructions here.)

Adding cloudflare repository GPG Keys
curl | sudo gpg --yes --dearmor --output /usr/share/keyrings/cloudflare-warp-archive-keyring.gpg
adding repository to apT
echo "deb [arch=amd64 signed-by=/usr/share/keyrings/cloudflare-warp-archive-keyring.gpg] $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/cloudflare-client.list
updating APT cache
sudo apt update
installing warp client
sudo apt install cloudflare-warp

After install, we have to set the WARP Client in proxy mode

Setting Cloudflare WARP to Proxy Mode

To do this, first you’ll have to register the client by accepting Cloudflare’s Terms of Service and Privacy Policy.

warp-cli register
Accepting Cloudflare TOS & Privacy Policy

After accepting the terms, you can now set the client mode to proxy. To do this, execute the following command.

warp-cli set-mode proxy
Setting mode to proxy
changing proxy port

You may change the port on which Cloudflare proxy runs by running the following command, where the number at the end is the port in which the proxy is listening to. Keep a note of this as we will need this later.

warp-cli set-proxy-port 5423
Change WARP proxy port
connecting cloudflare client

You can now connect to the Cloudflare network by using the following command.

warp-cli connect
connecting to cloudflare
checking connection status (optional)
warp-cli warp-stats
warp connection status

Installing Squid Proxy

Now that you have configured Cloudflare WARP, we can install Squid Proxy.

sudo apt install squid

After install, we can navigate to the Squid configuration directory to start editing files.

cd /etc/squid

Editing Squid Configuration files

Using your favorite, text editor, edit the squid.conf file in the directory (you need to be superuser to edit the files). For convenience, I will be using nano.

sudo nano squid.conf

You will have to add these line at the top of the file.

changing the port squid runs on (optional)
http_port 8080

This code makes Squid run on port 8080.

adding port 80 acl
acl port80 port 80

We need to specify port 80 for our next command

preventing traffic which is not on port 80 from being forwarded to origin
never_direct allow !port80

This code essentially forwards all traffic which is not on port 80 to the proxy.

Note: Traffic on port 80 does not go well with Cloudflare proxy.

Adding cloudflare proxy
cache_peer parent 5423 0 default no-query

This code adds the WARP client running on port 5423 as a cache peer.

Finally, the code should be looking like this.

squid configuration

Save and exit nano by CTRL + X and then by clicking Y.

Restart Squid Proxy

Now that the changes are done, you can restart squid proxy to apply your changes.

sudo systemctl restart squid

Testing the connections

After the restart, we can test if squid is successfully forwarding the connections to Cloudflare WARP by using the following curl command.

curl -x http://localhost:8080 | grep warp

After executing the command, if you get warp=on then squid is successfully forwarding your requests to cloudflare.

viewing results