art

Implementation of the Asynchronous Ratcheting Tree data structure and associated protocols, based on the CCS'19 paper "On Ends-to-Ends Encrytpion" by Cohn-Gordon, et al.

Building

To build the command-line utilities, do:

make

There is a also a clean target to delete these built utilities:

make clean

Running

1. Start with generating identity and ephemeral keys for the participants

   # Generating individually
   ./genpkey -keytype ek alice
   ./genpkey -keytype ik alice
   
   # Generating in bulk
   for name in alice bob cici dave; do for type in ik ek; do ./genpkey -keytype $type $name; done; done

   Move the certificates to data folder after generation.

   mv *.pem cmd/setup_group/data/

2. Initiating Group Setup (initiator here = alice)

   ./setup_group -initiator alice ./cmd/setup_group/data/4.conf ./cmd/setup_group/data/alice-ik.pem
   

3. For processing the setup message by another participant (participant here = bob, index = 2)

   ./process_setup_message -out-state bob-state.json 2 ./cmd/setup_group/data/bob-ek.pem ./cmd/setup_group/data/alice-ik-pub.pem 4.conf.dir/setup.msg
   

4. Update Key: Cici updates her key (assuming Cici already has been setup as a member)

   ./update_key -update-file cici_update_key 3 cici-state.json
   

5. Process Update Message: Bob applies the key update message sent by Cici in Step 4

   ./process_update_message 2 ./cmd/setup_group/data/bob-ek.pem bob-state.json cici_update_key