whisper

README

Overview

A simple lib to encrypt, decrypt data with Public-key cryptography. Now ED25519, ECDSA, and RSA are supported.

Features:

• Use the existing ssh key pairs and github public key url, no need to generate new key pair.
• Auto find the right key to decrypt.
• Encrypt data for multiple recipients.
• ssh-agent like server to cache the private key passphrase.
• Optional signing for integrity check.
• Lower overhead and small wire format.
• Streamlined design for large file encryption.

CLI tool

Installation

Use it as lib or CLI tool.

Go to the release page to download the CLI binary.

If you have golang installed:

go install github.com/ysmood/whisper@latest

Usage

Here is a simple example to encrypt and decrypt for yourself, the encrypted data can only be decrypted by your private key.

# generate a key pair
ssh-keygen -t ed25519 -N "" -f id_ed25519

echo 'hello world!' > hello.txt

# Encrypt file hello.txt to a whisper file hello.wsp .
# It will auto start a agent server to cache the passphrase so you don't have to retype it.
whisper -e='id_ed25519.pub' hello.txt > hello.wsp

# Decrypt file encrypted to stdout
whisper -p='id_ed25519' hello.wsp
# hello world!

# You can also use it as a pipe
cat hello.txt | whisper -e='id_ed25519.pub' > hello.wsp
cat hello.wsp | whisper -p='id_ed25519'

You can also use a url for a remote public key file. Here we use my public key on github to encrypt the data. Github generally exposes your public key file at @https://github.com/{YOUR_ID}.keys.

# For github you can use the user id directly.
# Here the user id is 'ysmood'.
whisper -e='@ysmood' hello.txt > hello.wsp

# For other sites you can use the full url.
whisper -e='@https://gitlab.com/jack.keys' hello.txt > hello.wsp

# A authorized_keys file may contain several keys,
# you can add a suffix to select a specific key to encrypt.
# 'ed25519' is the substring of the key we want to use.
whisper -e='@ysmood:ed25519' hello.txt > hello.wsp

# Encrypt content for multiple recipients, such as Jack and Tim.
whisper -e='@jack' -e='@tim' hello.txt > hello.wsp

# Decrypt on Jack's machine, the machine has Jack's private key.
whisper hello.wsp

# To sign and encrypt the data, you can use the `-s` flag.
whisper -s='@ysmood' -e='@jack' hello.txt > hello.wsp

# To verify the signature and decrypt the data.
# If -s flag is not provided, it will only decrypt the data.
whisper -s='@ysmood' hello.wsp