Asymmetric Cryptography Demo

Demonstrates how asymmetric cryptography works using basic CLI tools.

• Age is used for encrypting and decrypting.
• ssh-keygen is used for creating and verifying signatures.

The keys we'll be using in this demo are your already-existing SSH keys.

Getting Started

Install dependencies

Make sure age is installed:

• macOS: brew install age
• Ubuntu: sudo apt update && sudo apt install age

Set up your repo

Copy .env.example to .env and fill it out with your information.

Do the same for allowed-signers.example. The allowed-signers file simply maps email addresses to public SSH keys.

Usage

If you want to encrypt a message that only Phil can decrypt:

./encrypt.sh [phil's email address]

Follow the prompts and a message + signature will be printed which you can copy / paste and send to Phil.

If you want to decrypt a message and verify that it actually came from Phil:

./decrypt_and_verify.sh [phil's email address]

Follow the prompts and you will see the encrypted message + signature verification results.