offline-protocol-sealed

The pieces both halves of a sealed conversation must agree on, in a form a bare-metal leaf node can link: the encrypted-envelope wire codec, address derivation, the canonical signing-payload construction, and the control frames a pair exchanges.

Provides:

• EncryptedMessage and its compact binary codec, the wire form of every sealed payload in the protocol
• derive_address, the SDK's one derivation of an address from an identity key
• canonical_payload, the domain-separated, length-prefixed construction every signature in the protocol is taken over
• The sender-ratchet and leaf key-package constants that a phone and a leaf must configure identically
• The six control-frame prefixes a 1:1 sealed conversation is carried on, and KeyPackagePayload, the body that advertises what a peer can parse

Like offline-protocol-core, this crate compiles for bare-metal targets with --no-default-features.

This crate is an internal layer of the SDK. Most Rust consumers want the main offline-protocol crate instead, and app developers want the React Native or Python bindings.

License

Copyright © 2025-2026 Offline Protocol, Inc.

Dual-licensed: AGPL-3.0-only for open-source use, or a commercial license for proprietary use.