openmls 1.4.2

Dart wrapper for OpenMLS — a Rust implementation of the Messaging Layer Security (MLS) protocol (RFC 9420)

1.4.2 - 2026-07-21

For Users

✨ Highlights

• openmls_frb v1.5.2 — Rust FFI bindings

Security

• Hardened MLS message parsing against malformed input — incoming MLS messages (mlsMessageExtractGroupId / mlsMessageExtractEpoch / mlsMessageContentType, plus Welcome / GroupInfo / process-message decoding) are now decoded via the Read-based path and reject trailing bytes explicitly, so a malformed message returns an error instead of aborting the process. Reported upstream; this local guard will be removed once we depend on a fixed openmls release.
• Triaged new libcrux advisories in the X-Wing PQ dependency tree (RUSTSEC-2026-0207/-0208/-0209/-0210/-0211/-0212) — these advisories were published against libcrux crates that reach our tree only transitively via the experimental X-Wing ciphersuite (pinned by openmls-v0.8.1, so not fixable via cargo update). Five are structurally unreachable (the SHA3 ones explicitly exclude ML-KEM; the AES-GCM ones are dead code — the only X-Wing suite is ChaCha20Poly1305); the sixth (-0212, libcrux-secrets constant-time swap on aarch64) is an accepted availability-only risk (CVSS VC:N/VI:N/VA:H — a wrong ML-KEM result makes an X-Wing operation fail, never a key leak). Per-advisory reachability analysis is documented inline in .cargo/audit.toml / rust/deny.toml; all clear on the next upstream OpenMLS bump. Classical (non-PQ) ciphersuites are unaffected.

Fixed

• Web build hook now refreshes stale WASM on upgrade — the web build hook records the provisioned crate version in web/pkg/.wasm-version and re-downloads when it changes, instead of skipping whenever the two WASM files merely exist. Previously, upgrading the package kept the prior version's WASM in the app's web/pkg/ (it survives flutter clean), so on web any FRB entry calling Dart store callbacks could panic with an argument-count mismatch (called Option::unwrap() on a None value) once the wire signature changed between versions. The download cache is now version-keyed (web/<version>/), WASM files are copied unconditionally (the old mtime guard skipped a fresh-but-older source on downgrade), and rust/Cargo.toml is a declared web-build dependency so a version bump re-runs the hook. Native platforms were unaffected.

For Contributors

Changed

• Adopt copier template v2.5.1 → v2.5.2 — source of the web build hook fix above.

1.4.1 - 2026-07-14

For Users

Highlights

• Hardened release binary & fail-closed supply chain — the shipped native library is now compiled with overflow-checks and unsafe_code = "deny", and the download hook refuses to load a binary whose SHA256 checksum cannot be verified.
• openmls — unchanged this release (openmls-v0.8.1)
• openmls_frb v1.5.0 → v1.5.1 — Rust FFI bindings (release binary rebuilt with overflow-checks; no API or behavior change in normal use)

Security

• Hardened release binary — the wrapper crate is now compiled with overflow-checks (integer overflow panics instead of wrapping silently) and unsafe_code = "deny" on all hand-written Rust. The few modules that legitimately need unsafe (the interior-mutability storage shim and the WASM WasmCryptoKey Send + Sync impl) opt in explicitly; the FRB-generated bridge is exempt.
• Fail-closed download verification — the native-library build hook now aborts if the SHA256 checksums cannot be fetched or lack an entry for the archive, instead of loading an unverified binary. An OPENMLS_ALLOW_UNVERIFIED_DOWNLOAD=1 escape hatch is provided for older releases published without a checksums file.

For Contributors

Added

• cargo-deny (rust/deny.toml, make rust-deny, CI deny job) — enforces RustSec advisories, an allowed-license list, and a source allow-list. Remediated RUSTSEC-2026-0204 (crossbeam-epoch 0.9.18 → 0.9.20); six unremediable/inapplicable advisories are ignored with inline justifications (the three libcrux crypto advisories mirror .cargo/audit.toml).
• cargo-fuzz harness (rust/fuzz/, Fuzz workflow, make fuzz*) with two targets over untrusted wire bytes — mls_message (MLS protocol-message parsers) and credential (MlsCredential::deserialize) — plus a seed-corpus generator (make fuzz-seed).
• Rust clippy in CI (make rust-clippy, -D warnings) and a pinned FRB codegen installer (make setup-frb-codegen) so CI and local codegen produce identical bindings.
• Download-cache tests (test/hook/build_hook_test.dart).

Changed

• Adopt copier template v2.4.0 → v2.5.1
  • Fixed the download cache key (crate version + full platform variant) so iOS device and simulator builds no longer poison each other's cache on Apple-silicon hosts
  • Update scripts: check_updates.dart --update now bumps the wrapper crate version, update_changelog.dart classifies update severity and accepts --from, and the update workflow skips regeneration when an open PR for the same version already exists
  • Fixed pre-existing clippy findings (CryptoError Copy deref; too_many_arguments on external-commit APIs)

1.4.0 - 2026-06-06

For Users

Highlights

• openmls_frb v1.4.0 → v1.5.0 — experimental X-Wing post-quantum ciphersuite (hybrid ML-KEM-768 + X25519)

Added

• Experimental post-quantum ciphersuite: MlsCiphersuite.mls256XwingChacha20Poly1305Sha256Ed25519 — hybrid X-Wing KEM (ML-KEM-768 + X25519, draft-connolly-cfrg-xwing-kem-06) for harvest-now-decrypt-later protection. HPKE operations for this suite are delegated to the formally verified libcrux ML-KEM implementation (openmls_libcrux_crypto, same upstream openmls-v0.8.1 pin); all classical ciphersuites continue to run unchanged on RustCrypto. The libcrux provider is initialized lazily — classical suites never depend on it. See the README "Post-Quantum Support (Experimental)" section for important limitations (no IANA codepoint, limited interoperability, future migration to the official IETF suite).

Security

• cargo audit reports three RustSec advisories introduced into the dependency tree by openmls_libcrux_crypto (RUSTSEC-2026-0124, RUSTSEC-2026-0075, RUSTSEC-2026-0073). Analysis: all are DoS-class (panic) or structurally unreachable through this library's call paths — signatures always run on RustCrypto (0075 path never invoked; libcrux's KEM/HPKE code does not link ed25519), HPKE buffers are exact-size library-allocated (0124 trigger impossible), and the standalone mac() (0073) is never called. Fixes are blocked on upstream semver pins; tracked until the next upstream OpenMLS release. Each advisory is ignored in .cargo/audit.toml with its reachability justification inline — remove those entries when bumping the upstream pin. The non-libcrux routing these justifications depend on is enforced by the classical_ops_do_not_init_libcrux Rust test.

Documentation

• Document flutter build web --wasm (dart2wasm) limitation in README — Rust returns fail with Type 'JSValue' is not a subtype of type 'List<dynamic>' under dart2wasm. Upstream limitation in flutter_rust_bridge (#2575), affects every FRB-based Dart package. Standard flutter build web (dart2js) target continues to work. (#5)

1.3.0 - 2026-04-01

For Users

Highlights

• openmls_frb v1.3.0 → v1.4.0 — update flutter_rust_bridge to v2.12.0

Changed

• Update flutter_rust_bridge from v2.11.1 to v2.12.0 — fixes codegen/runtime version mismatch when consumers resolve FRB 2.12.x (#4)

1.2.0 - 2026-02-18

For Users

Highlights

• openmls_frb v1.2.0 → v1.3.0 — database migration system with schema versioning

Added

• MlsEngine.schemaVersion() — returns the current database schema version (useful for diagnostics and debugging)

For Contributors

Added

• Database migration system with automatic schema versioning and downgrade detection
  • Native (SQLCipher): each migration runs in its own SQL transaction with version written atomically
  • WASM (IndexedDB): two-phase approach — structural changes via IDB versioning, data migrations via encrypted metadata key
  • Downgrade detection: clear error if DB was created by a newer library version
  • Separate version counters: LATEST_SCHEMA_VERSION (data format, both platforms) and IDB_STRUCTURAL_VERSION (IDB object stores, WASM only)
• /add-db-migration Claude skill — step-by-step guide for adding new migrations
• Storage Architecture section in CLAUDE.md — snapshot pattern, scalability, security properties, Wire comparison
• DB migration reminder in openmls update workflow PR checklist

Fixed

• Fix WASM build failure caused by idb 0.6.5 API changes in encrypted_db.rs (VersionChangeEvent::old_version() now returns Result<u32>, Uint8Array::into() requires explicit type)

Changed

• Adopt copier template v2.3.1 → v2.4.0
  • Added coverage badge support in README (shields.io endpoint via GitHub Gist)
  • Added Rust dependency caching (Swatinem/rust-cache@v2) in CI setup-rust action — dramatically speeds up Windows builds (~10 min OpenSSL compile cached)
  • Added Strawberry Perl configuration for Windows CI to fix OpenSSL build (MSYS2 Perl from Git Bash is incompatible)
  • Added IPHONEOS_DEPLOYMENT_TARGET env var for iOS CI builds — fixes linker errors when vendored C code is compiled with newer Xcode
  • Added make check-targets command and scripts/check_deployment_targets.dart for checking deployment target consistency (iOS/macOS/Android) across all project files
  • Added "Setting up Coverage Badge" and "Setting up pub.dev Publishing" sections to CONTRIBUTING.md
  • Replaced dart run scripts/ with dart scripts/ in Makefile commands, removing .skip_openmls_hook workaround (scripts only use dart: imports, so dart run build hooks are unnecessary)
  • Fixed WASM build hook: local builds now take priority over cached/downloaded files, avoiding stale content hash mismatches
  • Removed flutter: version constraint from pubspec.yaml environment (pure Dart packages don't need it)
  • README: compact horizontal platform table, added "Developing Rust API", "Building Native Libraries", and "CI / Version Management" sections

1.1.0 - 2026-02-15

For Users

Highlights

• openmls_frb v1.0.0 → v1.2.0 — Rust FFI bindings with engine close/reopen support and openmls v0.8.1

Added

• MlsEngine.close() and MlsEngine.isClosed() — allow closing the engine (wiping the encryption key from RAM and closing the DB connection) when the app goes to background or the screen is locked. After close, all operations fail with "MlsEngine is closed". Close is idempotent

Changed

• Update openmls native library to v0.8.1 (release notes)
  • Relaxed WASM size limit to improve compatibility
  • Exposed full_leaves and parents in TreeSync for tree traversal
  • Updated libcrux and hpke-rs dependencies

Fixed

• README: Correct iOS minimum version from 12.0 to 13.0 and macOS from 10.14 to 10.15 in platform support table

For Contributors

Added

• make check-targets: Unified deployment target consistency checker for iOS, macOS, and Android — verifies all project files (podspec, CI workflow, Xcode project, plist, build.gradle, README) match .copier-answers.yml. Supports --update to fix mismatches and --set <version> to change a platform target everywhere in one command

Changed

• CI: Add Rust dependency caching (Swatinem/rust-cache) to speed up builds, especially Windows where vendored OpenSSL compilation took ~10 minutes

1.0.1 - 2026-02-11

Added

• Coverage badge

1.0.0 - 2026-02-11

Added

• MLS Protocol (RFC 9420): Full group key agreement with forward secrecy and post-compromise security
• MlsEngine: Rust-owned encrypted database with 61 API functions (58 async + 3 sync):
  • Group creation, join (Welcome, external commit), leave
  • Member management (add, remove, swap)
  • Encrypted messaging with additional authenticated data (AAD)
  • Proposals (add, remove, self-update with custom leaf node parameters, PSK, custom, group context extensions)
  • Commit handling (pending, flexible, merge/clear)
  • State queries (members, epoch, extensions, configuration, epoch authenticator, ratchet tree, group info, secrets)
  • Key package creation with options (lifetime, last-resort)
  • Storage cleanup (delete group, delete key package, remove pending proposal)
  • Basic and X.509 credential support (optional credential bytes on all creation functions)
  • 3 sync message utilities (extract group ID, epoch, content type)
• Encrypted storage: All MLS state encrypted at rest
  • Native: SQLCipher (AES-256 transparent full-database encryption)
  • Web: IndexedDB + AES-256-GCM per-value encryption via Web Crypto API
• SecureBytes: Wrapper for sensitive byte data with automatic zeroing on disposal
• SecureUint8List: Extension with zeroize() method for manual zeroing of Uint8List
• Cross-platform support: Android, iOS, macOS, Linux, Windows, Web (WASM)
• Automatic native library download via Dart Build Hooks
• SHA256 checksum verification for supply chain security
• Based on OpenMLS v0.8.0

Security

• All cryptographic operations run in Rust (OpenMLS with RustCrypto backend)
• Memory safety via Rust's ownership model
• No unsafe code in the wrapper layer
• Web Crypto API on WASM: Encryption key imported as non-extractable CryptoKey via crypto.subtle.importKey() — raw key bytes zeroized from WASM memory immediately after import. Defensive error handling (no unwrap()) in encrypt/decrypt paths
• SerializableSigner derives ZeroizeOnDrop — private key bytes zeroed on drop
• Eliminated clone-then-zeroize pattern in from_raw() and serialize_signer() — private keys moved, not copied
• signer_from_bytes() zeroizes input bytes on all code paths, including deserialization errors
• X.509 x509() documents that application layer must validate certificate chains
• SECURITY.md: sensitive API table, known limitations, web deployment recommendations, vulnerability reporting via GitHub Security Advisories