/mute

Mute — secure messaging

Primary LanguageGoBSD 3-Clause "New" or "Revised" LicenseBSD-3-Clause

Mute — secure messaging — α release

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This is an alpha release of Mute — use at your own risk! There are known bugs, all sorts of things might go wrong, and you might not be able to keep registered user IDs. At the moment, you can only play with the command-line interface mutectrl, a graphical user interface will be released at a later stage.

Features

  • End-to-end encryption.
  • Communication with forward secrecy (keys required to decrypt past messages are frequently replaced and destroyed).
  • Establish forward secret communication with first message (no synchronous two-way handshake).
  • Asynchronous communication between peers.
  • Authenticity of the identity-key relationship is established and preserved.
  • Human-readable/human-memorizable identities.
  • Communication with established standards where possible (e.g., using SMTP as the transport protocol).
  • Sending messages and changing the state of one's own identity requires payment by the user to both finance the system and to limit SPAM.
  • Better-than-nothing anonymity: mixing/delaying of messages to prevent simple discovery of sender-recipient relationship by third party passive observer.
  • Both sender and recipient anonymity.
  • Plausible deniability of message content and some deniability of communication relationship.

Installation

At the moment, only installation from source is supported. You must have at least Go 1.6 installed (with GOPATH set accordingly and $GOPATH/bin being part of your PATH).

To install mutectrl execute the following three commands:

go get -u -v github.com/mutecomm/mute/cmd/mutegenerate
go generate -v github.com/mutecomm/mute/release
go get -u -v github.com/mutecomm/mute/cmd/...

Setup

Before you can start using mutectrl you have to create your encrypted database files with a passphrase. The following command does just that (and reads the passphrase from stdin):

mutectrl --passphrase-fd stdin db create

This also fetches the necessary configuration settings from our config server and prints your WALLETPUBKEY (you can always print your wallet key with mutectrl wallet pubkey).

To be able to use Mute we have to charge your wallet. For now, this is absolutely free of charge. Just send an email to frank@cryptogroup.net with your wallet pubkey. The payment tokens you receive are fully blinded before they are used to pay for Mute services, there is no way for us to connect the used tokens to your wallet pubkey!

Example usage

For the following commands you either have to enter your passphrase every time:

exec 3<`tty`; mutectrl ...

Or you can use the interactive mode described below.

To be able to send and receive messages you have to create a unique user ID (UID) for the @mute.one domain first:

mutectrl uid new --id your.name@mute.one

To be able to write somebody, you have to add him as a contact first:

mutectrl contact add --id your.name@mute.one --contact a_friend@mute.one

This automatically fetches all the necessary key material.

Now you can add a message to your friend to the outqueue (without actually sending it)

mutectrl msg add --from your.name@mute.one --to a_friend@mute.one --file msg.txt

Then send (all) messages from the outqueue:

mutectrl msg send --id your.name@mute.one

To check if your friend wrote you back already use the following commands:

mutectrl msg fetch --id your.name@mute.one
mutectrl msg list --id your.name@mute.one
mutectrl msg read --id your.name@mute.one --msgid X

(add help to a command to get help).

Messages are delayed and mixed with other messages on the server, so do not be surprised if your message is not delivered instantly.

Interactive mode

You can also use mutectrl in interactive mode:

exec 3<`tty`; mutectrl

help shows you all possible commands and with quit you can leave the interactive mode.

In interactive mode you have an active user ID which is used as the --id argument, if you do not specify it explicitly. Use mutectrl uid switch to switch the active UID.

Updates

You can automatically update mutectrl from source:

mutectrl upkeep update

Since this is an alpha release the software is evolving at a very high speed, please update frequently. We enforce an update, if your version is older than two weeks.

Backups

mutectrl writes its keys and messages to two encrypted databases in the directory given by option --homedir (default: ~/.config/mute). To backup your keys and messages, backup the following files in this directory:

keys.db
keys.key
msgs.db
msgs.key

The *.db files are the database files which are encrypted with a random key stored in the corresponding *.key file. The *.key files are protected by your passphrase. Make sure you keep backups of all four files and do not loose your passphrase!

Articles

Specification documents