ruby_olm
A Ruby wrapper for the olm double ratchet implementation from matrix.
This wrapper provides classes and methods that line up with the olm interface, as well as a set of helpers and short aliases.
Very much a work in progress.
Installation
The gem name is 'ruby_olm'. The target needs to be able to build native extensions.
Once installed, require as:
require 'ruby_olm'If using locally (i.e. you check out this repository) you may need to manually compile and clean the extensions like this:
bundle exec rake compile
bundle exec rake cleanCharacteristics
- Interfaces are not thread safe
- Olm always encodes binary as base64
- Account is unlikely to scale for a large number of one-time-keys
Example
Alice wants to send a message to Bob:
require 'ruby_olm'
include RubyOlm
alice = Account.new
bob = Account.new
# Alice wants to send a message to Bob
alice_msg = "hi bob"
# Bob generates a one-time-key
bob.gen_otk
# Alice must have Bob's identity and one-time-key to make a session
alice_session = alice.outbound_session(bob.ik['curve25519'], bob.otk['curve25519'].values.first)
# Bob marks all one-time-keys as published
bob.mark_otk
# Alice can encrypt
encrypted = alice_session.encrypt(alice_msg)
assert_instance_of PreKeyMessage, encrypted
# Bob can create a session from this first message
bob_session = bob.inbound_session(encrypted)
# Bob can now update his list of marked otk (since he knows one has been used)
bob.update_otk(bob_session)
# Bob can decrypt Alice's message
bob_msg = bob_session.decrypt(encrypted)
assert_equal alice_msg, bob_msg
# At this point Bob has received but Alice hasn't
assert bob_session.has_received?
refute alice_session.has_received?
# Bob can send messages back to Alice
bob_msg = "hi alice"
encrypted = bob_session.encrypt(bob_msg)
assert_instance_of Message, encrypted
alice_msg = alice_session.decrypt(encrypted)
assert_equal alice_msg, bob_msg Account and Session instances can be serialised and deserialised
using the #to_pickle and ::from_pickle methods. This is handy
for saving and restoring state:
# save
alice_saved_account = Alice.to_pickle
alice_saved_session = alice_session.to_pickle
# restore
Account.from_pickle(alice_saved_account)
Session.from_pickle(alice_saved_session)Running Tests
bundle exec rake testTodo
- documentation
- more testing
- add support for megolm
- replace built-in olm crypto with Ruby openssl
What is an Olm?
https://en.wikipedia.org/wiki/Olm.
License
Apache 2.0