http://crowanavoa5jrmcvafp72f5mirosab6emfurnwg7yv33oakm5obglhid.onion/about
What the server keeps For each user: username, a one-way hash of the passphrase, your public key, and the
secret key sealed with a key derived from your passphrase.
For each message: sender name, recipient id, sealed subject, sealed body, timestamps.