gbp-stack 1.2.1

Python bindings for the Group Protocol Stack: a layered, end-to-end encrypted group-messaging protocol family built on top of MLS (RFC 9420).

gbp-stack — Python bindings for the Group Protocol Stack

Python bindings for the Group Protocol Stack: a layered, end-to-end encrypted group-messaging protocol family built on top of MLS (RFC 9420).

This package wraps the native gbp_stack shared library through ctypes. The wheel for each supported platform bundles the appropriate native binary under gbp_stack/_native/<rid>/.

Layers

┌── application ──────────────────────────────────────────────────────┐
│   GtpClient · GapClient · GspClient   (TCP / UDP / SCTP-like)       │
├─────────────────────────────────────────────────────────────────────┤
│   GroupNode (GBP — IP-like base)                                    │
├─────────────────────────────────────────────────────────────────────┤
│   MlsContext (RFC 9420)                                             │
└─────────────────────────────────────────────────────────────────────┘

Sub-protocol toolkits

Beyond the protocol clients, the package ships ready-made helpers:

• MessageHistory + Watermark — bounded GTP message log + per-sender high-water mark for serving and consuming resync requests.
• JitterBuffer — bounded GAP reorder window keyed by media_source_id, with push, pop_in_order, pop_force and late-frame detection.
• RoleRegistry + Permissions — bind numeric role ids to permission bit-masks and check them with require / has.
• CapabilitiesNegotiator — track per-member advertisements and query the intersection, union, group_supports and missing views.
• SFrameSession + SFrameEncryptor — SFrame (draft-ietf-sframe-enc) E2EE for GAP audio frames; per-sender AES-GCM keys derived from MLS exporter, 1024-entry sliding-window replay protection.

Install

pip install gbp-stack==1.2.1

Quick start

from gbp_stack import MlsContext, GroupNode, GtpClient

with MlsContext.create("alice") as alice_mls, \
     MlsContext.create("bob")   as bob_mls:

    bob_kp  = bob_mls.export_key_package()
    welcome = alice_mls.invite(bob_kp)
    bob_mls.accept_welcome(welcome)

    group_id = alice_mls.group_id
    with GroupNode.create(member_id=1, group_id=group_id) as alice, \
         GroupNode.create(member_id=2, group_id=group_id) as bob, \
         GtpClient.create() as gtp_alice, \
         GtpClient.create() as gtp_bob:

        alice.bootstrap_as_creator(alice_mls.epoch)
        bob.bootstrap_as_joiner(bob_mls.epoch)

        frame = gtp_alice.send(alice, alice_mls, target=2,
                                message_id=0xCAFE_F00D, text="hello")
        for ev in bob.on_wire(bob_mls, frame.wire):
            if ev.kind == "payload_received" and ev.stream_type == 2:
                print(gtp_bob.accept(ev.plaintext).text)

License

Licensed under Apache License, Version 2.0.