Initial commit

.github/workflows/build.yml

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+# SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+#
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+name: Build and test Rust code
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  rust-build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Install cargo-machete
+        uses: taiki-e/install-action@cargo-machete
+      - name: Run cargo-machete
+        run: cargo machete
+
+      - name: Set up Rust toolchain
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: stable
+          components: clippy, rustfmt
+
+      - name: Rustfmt
+        run: cargo fmt -- --check
+
+      - name: Clippy
+        run: cargo clippy --locked --all-targets -- -D warnings
+
+      - name: Build
+        run: cargo build --verbose
+
+      - name: Tests
+        run: cargo test --verbose

.github/workflows/license.yml

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+# SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+#
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+name: REUSE Compliance Check
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: REUSE Compliance Check
+        uses: fsfe/reuse-action@v5

.gitignore

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+# SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+#
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+*/target
+*/Cargo.lock
+*/test
+target
+.DS_Store
+.vscode
+.ruby-version
+.env

Cargo.toml

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+# SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+#
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+[package]
+name = "mimi-protocol"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+serde_bytes = "0.11.15"

README.md

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+<!--
+SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+
+SPDX-License-Identifier: CC-BY-4.0
+-->
+
+# MIMI Message Content
+
+This repository contains the code for a Rust implementation of the [MIMI protocol draft](https://datatracker.ietf.org/doc/draft-ietf-mimi-protocol/).
+
+## Licensing
+
+All crates in this repository are licensed under the [AGPL 3.0](https://www.gnu.org/licenses/agpl-3.0.html). This README file is licensed under [CC-BY 4.0](https://creativecommons.org/licenses/by/4.0/).

REUSE.toml

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+# SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+#
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+version = 1
+
+[[annotations]]
+path = ["Cargo.lock"]
+SPDX-FileCopyrightText = "2024 Phoenix R&D GmbH <[email protected]>"
+SPDX-License-Identifier = "AGPL-3.0-or-later"

src/group_info.rs

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+// SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use serde_bytes::ByteBuf;
+
+use super::{CipherSuite, GroupInfo, RatchetTreeOption};
+
+// "to-be-signed"
+#[repr(u8)]
+pub enum GroupInfoRequestTBS {
+    Mls10 {
+        cipher_suite: CipherSuite,
+        requesting_signature_key: SignaturePublicKey,
+        requesting_credential: Credential,
+        group_info_public_key: HPKEPublicKey,
+        joining_code: Option<String>, // TODO: Or ByteBuf?
+    } = 1,
+}
+
+// TODO: The signed variant's joining code is not optional?
+
+// "to-be-encrypted"
+pub struct GroupInfoRatchetTreeTBE {
+    group_info: GroupInfo,
+    ratchet_tree_option: RatchetTreeOption,
+}
+
+// "to-be-signed"
+#[repr(u8)]
+pub enum GroupInfoResponseTBS {
+    Mls10 {
+        status: GroupInfoCode,
+        cipher_suite: CipherSuite,
+        room_id: ByteBuf,
+        hub_sender: ExternalSender,
+        encrypted_groupinfo_and_tree: ByteBuf,
+    } = 1,
+}
+
+// TODO: How to get signed/encrypted structs? Macros?

src/key_material.rs

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+// SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use super::{Capabilities, CipherSuite, IdentifierUri, KeyPackage, RequiredCapabilities};
+
+#[repr(u8)]
+pub enum KeyMaterialRequest {
+    Mls10 {
+        requesting_user: IdentifierUri,
+        target_user: IdentifierUri,
+        room_id: IdentifierUri,
+        acceptable_ciphersuites: Vec<CipherSuite>,
+        required_capabilities: RequiredCapabilities,
+    } = 1,
+}
+
+#[repr(u8)]
+pub enum KeyMaterialUserCode {
+    Success = 0,
+    PartialSuccess = 1,
+    IncompatibleProtocol = 2,
+    NoCompatibleMaterial = 3,
+    UserUnknown = 4,
+    NoConsent = 5,
+    NoConsentForThisRoom = 6,
+    UserDeleted = 7,
+    Custom(u8),
+}
+
+#[repr(u8)]
+pub enum Mls10ClientKeyMaterial {
+    Success {
+        // TODO: Ask if field order of client_status and client_uri can be swapped
+        client_uri: IdentifierUri,
+        key_package: KeyPackage,
+    } = 0,
+    KeyMaterialExhausted {
+        client_uri: IdentifierUri,
+    } = 1,
+    NothingCompatible {
+        client_uri: IdentifierUri,
+        client_capabilities: Option<Capabilities>,
+    } = 2,
+}
+
+#[repr(u8)]
+pub enum KeyMaterialResponse {
+    Mls10 {
+        user_status: KeyMaterialUserCode,
+        user_uri: IdentifierUri,
+        clients: Vec<Mls10ClientKeyMaterial>,
+    } = 1,
+}

src/lib.rs

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+// SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+mod group_info;
+mod key_material;
+mod notify;
+mod submit_message;
+mod update;
+
+// TODO: Import this from mls crate
+#[repr(u16)]
+pub enum CipherSuite {
+    Reserved = 0,
+    MLS_128_DHKEMX25519_AES128GCM_SHA256_Ed25519 = 1,
+    Custom(u16),
+}
+// TODO: Import this from mls crate
+pub type RequiredCapabilities = ();
+// TODO: Import this from mls crate
+pub type Capabilities = ();
+// TODO: Import this from mls crate
+pub type KeyPackage = ();
+// TODO: Import this from mls crate
+pub type MlsMessage = ();
+// TODO: Import this from mls crate
+pub type Welcome = ();
+// TODO: Import this from mls crate
+pub type GroupInfo = ();
+// TODO: Import this from mls crate
+pub type PartialGroupInfo = ();
+// TODO: Import this from mls crate
+pub type RatchetTreeOption = ();
+// TODO: Import this from mls crate
+pub type ProposalRef = ();
+
+#[repr(u8)]
+pub enum Protocol {
+    Reserved = 0,
+    Mls10 = 1,
+    Custom(u8),
+}
+
+pub struct IdentifierUri(String); // TODO: Or ByteBuf?

src/notify.rs

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+// SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use super::{MlsMessage, RatchetTreeOption};
+
+struct Frank {
+    franking_tag: [u8; 32], // TODO: The RFC starts mixing camelCase and snake_case
+    server_frank: [u8; 32],
+    server_frank_context_hash: [u8; 32],
+}
+
+enum Mls10FanoutMessage {
+    Application {
+        timestamp: u64,
+        message: MlsMessage,  // Must have wire_format = Application
+        frank: Option<Frank>, // In RFC, optional doesn't have the <>
+    },
+    Welcome {
+        timestamp: u64,
+        message: MlsMessage, // Must have wire_format = Welcome
+        ratchet_tree_option: RatchetTreeOption,
+    },
+}

src/submit_message.rs

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+// SPDX-FileCopyrightText: 2024 Phoenix R&D GmbH <[email protected]>
+//
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+use super::{IdentifierUri, MlsMessage};
+
+#[repr(u8)]
+pub enum SubmitMessageRequest {
+    Mls10 {
+        app_message: MlsMessage,
+        sending_uri: IdentifierUri,
+    } = 1,
+}
+
+#[repr(u8)]
+pub enum SubmitResponseStatus {
+    Success {
+        // TODO: RFC also calls this "Accepted"
+        accepted_timestamp: u64,
+        server_frank: Option<[u8; 32]>,
+    } = 0,
+    NotAllowed {} = 1,
+    EpochTooOld {
+        current_epoch: u64,
+    } = 2,
+}
+
+#[repr(u8)]
+pub enum SubmitMessageResponse {
+    Mls10 { status: SubmitResponseStatus } = 1,
+}