yashodhank / cathode

Demo App for ZeroTier SDK

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 Now with ENCRYPTED PACKET technology!

cathode

Encrypted P2P video chat in your terminal

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Cathode is a weakly-interacting coupling of two peices of software. First we start with p2pvc (the brilliant little app that renders the audio/video in your terminal), and then ZeroTier (an extremely small but very robust encrypted P2P virtual networking hypervisor). We use the library form found here. We then replace all of the socket API system calls with their libzt equivalents aaaaannnd we're done.

Hint: Use the Glass TTY VT220 font we've included. We think pairs well with cathode, installing this font and increasing your terminal's font size to about 24pt makes this whole experience much more immersive. Have fun!

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git submodule update --init --recursive

macOS

brew install pkg-config
brew tap homebrew/science
brew install portaudio opencv
make cathode
make install

linux

yum install portaudio opencv
make cathode
make install

• You might also need: portaudio-devel opencv-devel ncurses-devel

Usage

Generate ID (or display a previously generated ID)

• cathode -M

To view yourself:

• cathode -Z [your_id] -v

If you have a friend's ZeroTier ID or ZeroTier IP address you can connect to them via:

• cathode -Z [id] -v
• cathode -N [nwid] -R [id] -v
• cathode -N [nwid] -S [zt-ipv6-address] -v

Where -v is to enable video (as opposed to only audio)

Uninstall

• make uninstall

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Notes

This app is meant to be a simple demonstration of how you can add ZeroTier to your application. In this example there's only about ten points where modifications to p2pvc were needed. Since we want all network traffic to be handled by ZeroTier we swapped out the system's native calls with our own.

For instance, the p2plib.c's p2p_connect() function, we see:

con->socket = socket(curr_addr->ai_family, curr_addr->ai_socktype, curr_addr->ai_protocol);

We change it to the following:

con->socket = zts_socket(curr_addr->ai_family, curr_addr->ai_socktype, curr_addr->ai_protocol);

We also do this for every instance of bind(), connect(), accept(), listen(), etc. The substituted calls are designed to be perfectly compatible with each system's variation so substitution could be as simple as a find+replace.