signal-identity-tools

npm install signal-identity-tools

[WIP]

a keyserver and id generation tools for the signal-protocol

example

see example.js for a starting point.

the example does not cover uploading new unsignedPreKeys, or replacing signedPreKeys. see API for details.

(eventually this will all be wrapped in a friendlier way).

todos & cavaeats

• No rate-limiting or access control on PreKey fetches
  • This is necessary to make sure people don't deplete your one-time prekeys
• No validating uploaded keys (yet)
• The keyserver is just an API
  • You can wrap it in your own transport layer (HTTP, WS, etc)

api

let idtools = require('signal-identity-tools/idtools')

idtools.freshIdentity(keyId, store, cb)

keyId is a number.

store is a signal-protocol store (see signal-protocol).

Calls back on (err, { complete, sanitized, store }).

complete is the full identity, with secret keys. sanitized is the public-facing version, ready to send to the keyserver.

The store this method returns is the same store you pass in. I return it so you will notice that I am mutating it.

idtools.newSignedPreKey(identity, keyId, store, cb)

Like freshIdentity, calls back on (err, { complete, sanitized, store } )

sanitized is the public-facing version, ready to send to the keyserver.

idtools.newUnsignedPreKeys(n, keyId, cb)

Creates n unsigned (one-time) PreKeys.

Calls back on (err, { complete, sanitized } ), where both complete and sanitized are lists of keys of length n.

sanitized is the public-facing version, ready to send to the keyserver.

let keyserver = require('signal-identity-tools/keyserver')

ks = keyserver(level)

level is a leveldb-like instance.

You will want to configure your level db's encoding a bit, to allow for typed arrays:

// utilities for setting up level instances
var msgpack = require('msgpack-lite')
let valueEncoding = {encode: msgpack.encode,
                     decode: msgpack.decode,
                     buffer: true}
let level = require('level')
let opts = {valueEncoding: valueEncoding}
let db = level('/tmp/myKeyserverDb', opts)

ks.register(name, publicID, cb)

Registers a new username name, where publicID comes from the callback value of idtools.freshIdentity's .sanitized

cb(err)

ks.preKeyBundle(name, cb)

Calls back on the keyserver's next PreKeyBundle for a user name, per signal-protocol's spec for these bundles.

b(err, bundle)

ks.replaceSignedPreKey(name, signedPreKey, cb)

In the Signal protocol, users should replace their signed PreKeys occasionally.

This registers a new Signed PreKey for name, name, where signedPreKey comes from the callback value of idtools.newSignedPreKey's .sanitized.

cb(err)

ks.uploadUnsignedPreKeys(name, unisgnedPreKeys, cb)

In the Signal protocol, users must upload unsigned PreKeys regularly.

This uploads new, unsigned (one-time) PreKeys for name name, where unsignedPreKeys come from the callback value of idtools.newUnsignedPreKeys's .sanitized.

cb(err)

license

BSD