1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
// Wire
// Copyright (C) 2022 Wire Swiss GmbH

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program. If not, see http://www.gnu.org/licenses/.

use openmls::prelude::{hash_ref::ProposalRef, KeyPackage};

use mls_crypto_provider::MlsCryptoProvider;

use crate::{
    mls::{ClientId, ConversationId, MlsCentral, MlsConversation},
    prelude::{Client, CryptoError, CryptoResult, MlsProposalBundle},
};

/// Abstraction over a [openmls::prelude::hash_ref::ProposalRef] to deal with conversions
#[derive(Debug, Clone, Eq, PartialEq, derive_more::From, derive_more::Deref, derive_more::Display)]
pub struct MlsProposalRef(ProposalRef);

impl From<Vec<u8>> for MlsProposalRef {
    fn from(value: Vec<u8>) -> Self {
        Self(ProposalRef::from_slice(value.as_slice()))
    }
}

impl MlsProposalRef {
    /// Duh
    pub fn into_inner(self) -> ProposalRef {
        self.0
    }

    pub(crate) fn to_bytes(&self) -> Vec<u8> {
        self.0.as_slice().to_vec()
    }
}

#[cfg(test)]
impl From<MlsProposalRef> for Vec<u8> {
    fn from(prop_ref: MlsProposalRef) -> Self {
        prop_ref.0.as_slice().to_vec()
    }
}

/// Internal representation of proposal to ease further additions
// KeyPackage is large
#[allow(clippy::large_enum_variant)]
pub enum MlsProposal {
    /// Requests that a client with a specified KeyPackage be added to the group
    Add(KeyPackage),
    /// Similar mechanism to Add with the distinction that it replaces
    /// the sender's LeafNode in the tree instead of adding a new leaf to the tree
    Update,
    /// Requests that the member with LeafNodeRef removed be removed from the group
    Remove(ClientId),
}

impl MlsProposal {
    /// Creates a new proposal within the specified `MlsGroup`
    async fn create(
        self,
        client: &Client,
        backend: &MlsCryptoProvider,
        mut conversation: impl std::ops::DerefMut<Target = MlsConversation>,
    ) -> CryptoResult<MlsProposalBundle> {
        let proposal = match self {
            MlsProposal::Add(key_package) => {
                (*conversation)
                    .propose_add_member(client, backend, key_package.into())
                    .await
            }
            MlsProposal::Update => (*conversation).propose_self_update(client, backend).await,
            MlsProposal::Remove(client_id) => {
                let index = conversation
                    .group
                    .members()
                    .find(|kp| kp.credential.identity() == client_id.as_slice())
                    .ok_or(CryptoError::ClientNotFound(client_id))
                    .map(|kp| kp.index)?;
                (*conversation).propose_remove_member(client, backend, index).await
            }
        }?;
        Ok(proposal)
    }
}

impl MlsCentral {
    /// Creates a new Add proposal
    #[cfg_attr(test, crate::idempotent)]
    pub async fn new_add_proposal(
        &mut self,
        id: &ConversationId,
        key_package: KeyPackage,
    ) -> CryptoResult<MlsProposalBundle> {
        self.new_proposal(id, MlsProposal::Add(key_package)).await
    }

    /// Creates a new Add proposal
    #[cfg_attr(test, crate::idempotent)]
    pub async fn new_remove_proposal(
        &mut self,
        id: &ConversationId,
        client_id: ClientId,
    ) -> CryptoResult<MlsProposalBundle> {
        self.new_proposal(id, MlsProposal::Remove(client_id)).await
    }

    /// Creates a new Add proposal
    #[cfg_attr(test, crate::dispotent)]
    pub async fn new_update_proposal(&mut self, id: &ConversationId) -> CryptoResult<MlsProposalBundle> {
        self.new_proposal(id, MlsProposal::Update).await
    }

    /// Creates a new proposal within a group
    ///
    /// # Arguments
    /// * `conversation` - the group/conversation id
    /// * `proposal` - the proposal do be added in the group
    ///
    /// # Return type
    /// A [MlsProposalBundle] with the proposal in a Mls message and a reference to that proposal in order to rollback it if required
    ///
    /// # Errors
    /// If the conversation is not found, an error will be returned. Errors from OpenMls can be
    /// returned as well, when for example there's a commit pending to be merged
    async fn new_proposal(&mut self, id: &ConversationId, proposal: MlsProposal) -> CryptoResult<MlsProposalBundle> {
        let conversation = self.get_conversation(id).await?;
        let client = self.mls_client()?;
        proposal
            .create(client, &self.mls_backend, conversation.write().await)
            .await
    }
}

#[cfg(test)]
mod tests {
    use wasm_bindgen_test::*;

    use crate::{prelude::MlsCommitBundle, prelude::*, test_utils::*};

    wasm_bindgen_test_configure!(run_in_browser);

    mod add {
        use super::*;

        #[apply(all_cred_cipher)]
        #[wasm_bindgen_test]
        pub async fn should_add_member(case: TestCase) {
            run_test_with_client_ids(
                case.clone(),
                ["alice", "bob"],
                move |[mut alice_central, mut bob_central]| {
                    Box::pin(async move {
                        let id = conversation_id();
                        alice_central
                            .mls_central
                            .new_conversation(&id, case.credential_type, case.cfg.clone())
                            .await
                            .unwrap();
                        let bob_kp = bob_central.mls_central.get_one_key_package(&case).await;
                        alice_central.mls_central.new_add_proposal(&id, bob_kp).await.unwrap();
                        let MlsCommitBundle { welcome, .. } = alice_central
                            .mls_central
                            .commit_pending_proposals(&id)
                            .await
                            .unwrap()
                            .unwrap();
                        alice_central.mls_central.commit_accepted(&id).await.unwrap();
                        assert_eq!(
                            alice_central
                                .mls_central
                                .get_conversation_unchecked(&id)
                                .await
                                .members()
                                .len(),
                            2
                        );
                        let new_id = bob_central
                            .mls_central
                            .process_welcome_message(welcome.unwrap().into(), case.custom_cfg())
                            .await
                            .unwrap()
                            .id;
                        assert_eq!(id, new_id);
                        assert!(bob_central
                            .mls_central
                            .try_talk_to(&id, &mut alice_central.mls_central)
                            .await
                            .is_ok());
                    })
                },
            )
            .await
        }
    }

    mod update {
        use super::*;
        use itertools::Itertools;

        #[apply(all_cred_cipher)]
        #[wasm_bindgen_test]
        pub async fn should_update_hpke_key(case: TestCase) {
            run_test_with_central(case.clone(), move |[mut central]| {
                Box::pin(async move {
                    let id = conversation_id();
                    central
                        .mls_central
                        .new_conversation(&id, case.credential_type, case.cfg.clone())
                        .await
                        .unwrap();
                    let before = central
                        .mls_central
                        .get_conversation_unchecked(&id)
                        .await
                        .encryption_keys()
                        .find_or_first(|_| true)
                        .unwrap();
                    central.mls_central.new_update_proposal(&id).await.unwrap();
                    central.mls_central.commit_pending_proposals(&id).await.unwrap();
                    central.mls_central.commit_accepted(&id).await.unwrap();
                    let after = central
                        .mls_central
                        .get_conversation_unchecked(&id)
                        .await
                        .encryption_keys()
                        .find_or_first(|_| true)
                        .unwrap();
                    assert_ne!(before, after)
                })
            })
            .await
        }
    }

    mod remove {
        use super::*;

        #[apply(all_cred_cipher)]
        #[wasm_bindgen_test]
        pub async fn should_remove_member(case: TestCase) {
            run_test_with_client_ids(case.clone(), ["alice", "bob"], |[mut alice_central, mut bob_central]| {
                Box::pin(async move {
                    let id = conversation_id();
                    alice_central
                        .mls_central
                        .new_conversation(&id, case.credential_type, case.cfg.clone())
                        .await
                        .unwrap();
                    alice_central
                        .mls_central
                        .invite_all(&case, &id, [&mut bob_central.mls_central])
                        .await
                        .unwrap();
                    assert_eq!(
                        alice_central
                            .mls_central
                            .get_conversation_unchecked(&id)
                            .await
                            .members()
                            .len(),
                        2
                    );
                    assert_eq!(
                        bob_central
                            .mls_central
                            .get_conversation_unchecked(&id)
                            .await
                            .members()
                            .len(),
                        2
                    );

                    let remove_proposal = alice_central
                        .mls_central
                        .new_remove_proposal(&id, bob_central.mls_central.get_client_id())
                        .await
                        .unwrap();
                    bob_central
                        .mls_central
                        .decrypt_message(&id, remove_proposal.proposal.to_bytes().unwrap())
                        .await
                        .unwrap();
                    let MlsCommitBundle { commit, .. } = alice_central
                        .mls_central
                        .commit_pending_proposals(&id)
                        .await
                        .unwrap()
                        .unwrap();
                    alice_central.mls_central.commit_accepted(&id).await.unwrap();
                    assert_eq!(
                        alice_central
                            .mls_central
                            .get_conversation_unchecked(&id)
                            .await
                            .members()
                            .len(),
                        1
                    );

                    bob_central
                        .mls_central
                        .decrypt_message(&id, commit.to_bytes().unwrap())
                        .await
                        .unwrap();
                    assert!(matches!(
                        bob_central.mls_central.get_conversation(&id).await.unwrap_err(),
                        CryptoError::ConversationNotFound(conv_id) if conv_id == id
                    ));
                })
            })
            .await
        }

        #[apply(all_cred_cipher)]
        #[wasm_bindgen_test]
        pub async fn should_fail_when_unknown_client(case: TestCase) {
            run_test_with_client_ids(case.clone(), ["alice"], move |[mut alice_central]| {
                Box::pin(async move {
                    let id = conversation_id();
                    alice_central
                        .mls_central
                        .new_conversation(&id, case.credential_type, case.cfg.clone())
                        .await
                        .unwrap();

                    let remove_proposal = alice_central
                        .mls_central
                        .new_remove_proposal(&id, b"unknown"[..].into())
                        .await;
                    assert!(matches!(
                        remove_proposal.unwrap_err(),
                        CryptoError::ClientNotFound(client_id) if client_id == b"unknown"[..].into()
                    ));
                })
            })
            .await
        }
    }
}