tmsg

Simple, decentralized multiparty chat and file sharing via tor and ecc for auth. Receiving peers run tmsg hidden services which handle incoming messages. If an incoming message starts with an line signed by a peer the rest of the message will be also verified against this peers public key and if this succeeds, the message is displayed. Incoming messages are automatically truncated at 4KB.

depends on socat, seccure, ksh

set up tor hidden service

start a hidden service like this in /etc/tor/torrc:

HiddenServiceDir /var/lib/tor/tmsg/
HiddenServicePort 80 127.0.0.1:14444

get your onion address from

sudo cat /var/lib/tor/tmsg/hostname

This hostname together with the HiddenServicePort 80 from above and your public key from ./pub form your complete address that you can share with your friends so you can have a two-way conversation. If you only share your public key, then you will be able to send to people accepting your key. But you can only be contacted, if you shared your onion address with others.

peers

create a list of all your peers data in this format

myself myaddress.onion <my public key>
friend 3m3k8x....onion <friends public key>
mom 8xj8nj38x....onion <moms public key>
myself2 my2ndaddress.onion <my other public key>

trailing space but no key, for read only address

mydeaddrop mydeadrop.onion 

twospaces before public key necessary, but no onion address

poster  <pseudonym public key>

multiple instances

You can run multiple tmsg instances in parallel, you just have to create more onion services, and run each tmsg in a separate directory You can change the local port for tmsg like this:

localport=14445 ./tmsg.sh

sending

example send to self (assuming you have a line with self and your onion address and public key in peers):

echo "snafu" | ./tsend.sh self

example send to multiple peers:

echo "immanentize the eschaton" | ./tsend.sh self hugo angela vlad kim

complete example

% git clone git://github.com/stef/tmsg.git
Cloning into 'tmsg'...
remote: Counting objects: 5, done.
remote: Compressing objects: 100% (5/5), done.
remote: Total 5 (delta 0), reused 5 (delta 0)
Receiving objects: 100% (5/5), done.
% cd tmsg
% ./tmsg.sh
your public key is: $Crmgt8UIjK|jzRP+UcpShH.7crWl6a0&=Dr<<)fl6|b:4}G70rycD$0Pov?X5(G-$pA?Iz:</(<|X6zL
don't forget to add your onion address to ./peers^Z
zsh: suspended  ./tmsg.sh
% sudo cat /var/lib/tor/tmsg/hostname
[sudo] password for stef: 
hvpd33rd4vhx4upd.onion
% echo 'self hvpd33rd4vhx4upd.onion:80 $Crmgt8UIjK|jzRP+UcpShH.7crWl6a0&=Dr<<)fl6|b:4}G70rycD$0Pov?X5(G-$pA?Iz:</(<|X6zL' >peers
% fg
[1]  + continued  ./tmsg.sh

Meanwhile in a different terminal (but the same directory):

% echo "hello world" | ./tsend.sh self

after some tor specific delay in the tmsg terminal:

2012-10-23T22:44:50.717327580+0200 <self> hello world
^C

poor mans repl

./tmsg.sh &; while read line; do echo "$line" | ./tsend.sh otheruser; done

wishlist

• support file uploads
• use ephemeral signing keys