Chainguard Container for squid-proxy

Squid Proxy is an open-source, high-performance, and highly configurable caching and forwarding web proxy. It is widely used for speeding up web servers by caching web, DNS, and other computer network lookups for a group of people sharing network resources, and for aiding security by filtering traffic.

Chainguard Containers are regularly-updated, secure-by-default container images.

Download this Container Image

For those with access, this container image is available on cgr.dev:

docker pull cgr.dev/ORGANIZATION/squid-proxy:latest

Be sure to replace the ORGANIZATION placeholder with the name used for your organization's private repository within the Chainguard Registry.

This image provides a high-performance Squid proxy server suitable for a wide range of caching and forwarding requirements. It is a drop-in replacement for traditional Squid proxy images but is enhanced for security and minimized to reduce its attack surface. Ideal for both development and production environments where a proxy server is required.

Note: We are running this image as non-root user called squid by default for more security.

Usage

Running the Squid Proxy Container

To run the squid-proxy container with default settings:

docker run --rm -p 3128:3128 cgr.dev/chainguard/squid-proxy:latest

Testing it with curl

export PROXY_HOST="localhost"
export PROXY_PORT="3128"
export URL="http://example.com"

curl -x http://"$PROXY_HOST":"$PROXY_PORT" "$URL" -o /dev/null -w '%{http_code}\n' -s

You will get a 403 response on this very likely, because of ACL on the default /etc/squid.conf. Access Control Lists (ACLs) in squid.conf are a crucial part of Squid's configuration. They allow you to define rules that grant or deny access to internet resources based on various criteria such as source IP, destination IP, URLs, protocols, and more.

Log may not be visible with default configuration, you can set it using the below custom configuration.

Custom Configuration For Docker

Add the following lines to the 'squid.conf' to redirect the logs to the '/dev/stdout':

http_port 3128
logfile_rotate 0
cache_log stdio:/dev/stdout
access_log stdio:/dev/stdout
cache_store_log stdio:/dev/stdout

For custom configurations, mount your squid.conf file into the container:

docker run --rm -v /path/to/your/squid.conf:/etc/squid.conf -p 3128:3128 cgr.dev/chainguard/squid-proxy:latest

Custom Configuration For Kubernetes

For working in Kubernetes, you can also run a parallel container in a pod containing squid container. This container will tail these (/var/log/squid/{cache,access}.log or any other) logs on its stdout.

---
kind: Pod
apiVersion: v1
metadata:
  name: squid-proxy
  labels:
    app: squid
spec:
  volumes:
  - name: log-dir
    emptyDir: {}
  containers:
  - name: squid
    image: cgr.dev/chainguard/squid-proxy:latest
    volumeMounts:
    - name: log-dir
      mountPath: "/var/log/squid/"
  - name: tailer
    image: busybox
    command:
    - "/bin/sh"
    - "-c"
    args:
    - tail -F /var/log/squid/access.log
    volumeMounts:
    - name: log-dir
      mountPath: "/var/log/squid/"

For more detailed instructions and advanced configurations, refer to the Squid Official Documentation.

What are Chainguard Containers?

Chainguard's free tier of Starter container images are built with Wolfi, our minimal Linux undistro.

All other Chainguard Containers are built with Chainguard OS, Chainguard's minimal Linux operating system designed to produce container images that meet the requirements of a more secure software supply chain.

The main features of Chainguard Containers include:

• Minimal design, without unnecessary software bloat
• Daily builds to ensure container images are up-to-date with available security patches
• High quality build-time SBOMs attesting to the provenance of all artifacts within the image
• Verifiable signatures provided by Sigstore
• Reproducible builds with Cosign and apko (read more about reproducibility)

For cases where you need container images with shells and package managers to build or debug, most Chainguard Containers come paired with a development, or -dev, variant.

In all other cases, including Chainguard Containers tagged as :latest or with a specific version number, the container images include only an open-source application and its runtime dependencies. These minimal container images typically do not contain a shell or package manager.

Although the -dev container image variants have similar security features as their more minimal versions, they include additional software that is typically not necessary in production environments. We recommend using multi-stage builds to copy artifacts from the -dev variant into a more minimal production image.

Need additional packages?

To improve security, Chainguard Containers include only essential dependencies. Need more packages? Chainguard customers can use Custom Assembly to add packages, either through the Console, chainctl, or API.

To use Custom Assembly in the Chainguard Console: navigate to the image you'd like to customize in your Organization's list of images, and click on the Customize image button at the top of the page.

Learn More

Refer to our Chainguard Containers documentation on Chainguard Academy. Chainguard also offers VMs and Libraries — contact us for access.

Trademarks

This software listing is packaged by Chainguard. The trademarks set forth in this offering are owned by their respective companies, and use of them does not imply any affiliation, sponsorship, or endorsement by such companies.