How do you use package signing and security with an example?

Package signing is a critical aspect of securing software installations on Linux systems. It ensures that the packages you install are authentic and have not been tampered with. Below is an overview of how package signing works, along with a practical example.

Understanding Package Signing

When a software package is created, the maintainers can sign it with a cryptographic key. This signature is then used to verify the integrity and authenticity of the package when it is installed on a system. Package managers like APT for Debian-based systems and YUM or DNF for Red Hat-based systems utilize these signatures to secure the installation process.

Example of Package Signing with APT

In this example, we will use APT package manager to install a package securely by verifying its signature.

        # To add a repository and verify its key
        sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 

        # Update package list
        sudo apt update

        # Install the package
        sudo apt install