Use rayon when generating welcome message (#9)

Co-authored-by: Marta Mularczyk <mulmarta@amazon.com>

mls-rs/benches/group_add.rs

@@ -9,6 +9,7 @@ use mls_rs::{
         basic::{BasicCredential, BasicIdentityProvider},
         SigningIdentity,
     },
+    mls_rules::{CommitOptions, DefaultMlsRules},
     CipherSuite, CipherSuiteProvider, Client, CryptoProvider,
 };
 use mls_rs_crypto_openssl::OpensslCryptoProvider;
@@ -70,6 +71,10 @@ fn make_client(name: &str) -> Client<impl MlsConfig> {
     Client::builder()
         .crypto_provider(crypto_provider)
         .identity_provider(BasicIdentityProvider)
+        .mls_rules(
+            DefaultMlsRules::new()
+                .with_commit_options(CommitOptions::new().with_ratchet_tree_extension(false)),
+        )
         .signing_identity(
             SigningIdentity::new(
                 BasicCredential::new(name.as_bytes().to_vec()).into_credential(),

mls-rs/src/group/commit.rs

@@ -21,6 +21,9 @@ use crate::{
     ExtensionList, MlsRules,
 };
 
+#[cfg(all(not(mls_build_async), feature = "rayon"))]
+use {crate::iter::ParallelIteratorExt, rayon::prelude::*};
+
 use crate::tree_kem::leaf_node::LeafNode;
 
 #[cfg(not(feature = "private_message"))]
@@ -606,16 +609,13 @@ where
 
         // Encrypt path secrets and joiner secret to new members
         let path_secrets = path_secrets.as_ref();
-        let mut welcome_messages = Vec::new();
-        let mut encrypted_path_secrets = Vec::new();
-
-        let added_key_pkgs = added_key_pkgs
-            .into_iter()
-            .zip(provisional_state.indexes_of_added_kpkgs);
 
-        for (key_package, leaf_index) in added_key_pkgs {
-            let secret = self
-                .encrypt_group_secrets(
+        #[cfg(not(any(mls_build_async, not(feature = "rayon"))))]
+        let encrypted_path_secrets: Vec<_> = added_key_pkgs
+            .into_par_iter()
+            .zip(provisional_state.indexes_of_added_kpkgs)
+            .map(|(key_package, leaf_index)| {
+                self.encrypt_group_secrets(
                     &key_package,
                     leaf_index,
                     &key_schedule_result.joiner_secret,
@@ -624,20 +624,43 @@ where
                     psks.clone(),
                     &encrypted_group_info,
                 )
-                .await?;
-
-            if commit_options.single_welcome_message {
-                encrypted_path_secrets.push(secret);
-            } else {
-                welcome_messages
-                    .push(self.make_welcome_message(vec![secret], encrypted_group_info.clone()));
+            })
+            .try_collect()?;
+
+        #[cfg(any(mls_build_async, not(feature = "rayon")))]
+        let encrypted_path_secrets = {
+            let mut secrets = Vec::new();
+
+            for (key_package, leaf_index) in added_key_pkgs
+                .into_iter()
+                .zip(provisional_state.indexes_of_added_kpkgs)
+            {
+                secrets.push(
+                    self.encrypt_group_secrets(
+                        &key_package,
+                        leaf_index,
+                        &key_schedule_result.joiner_secret,
+                        path_secrets,
+                        #[cfg(feature = "psk")]
+                        psks.clone(),
+                        &encrypted_group_info,
+                    )
+                    .await?,
+                );
             }
-        }
 
-        if commit_options.single_welcome_message && !encrypted_path_secrets.is_empty() {
-            welcome_messages =
-                vec![self.make_welcome_message(encrypted_path_secrets, encrypted_group_info)];
-        }
+            secrets
+        };
+
+        let welcome_messages =
+            if commit_options.single_welcome_message && !encrypted_path_secrets.is_empty() {
+                vec![self.make_welcome_message(encrypted_path_secrets, encrypted_group_info)]
+            } else {
+                encrypted_path_secrets
+                    .into_iter()
+                    .map(|s| self.make_welcome_message(vec![s], encrypted_group_info.clone()))
+                    .collect()
+            };
 
         let commit_message = self.format_for_wire(auth_content.clone()).await?;
 

mls-rs/src/group/mod.rs

@@ -2176,9 +2176,6 @@ mod tests {
         (test_group, commit)
     }
 
-    // This test actually compiles without the by_ref_proposal feature, but it fails at runtime
-    // because the group context extensions seem to be updated only when this feature is enabled.
-    #[cfg(feature = "by_ref_proposal")]
     #[maybe_async::test(not(mls_build_async), async(mls_build_async, crate::futures_test))]
     async fn test_group_context_ext_proposal_commit() {
         let mut extension_list = ExtensionList::new();

mls-rs/test_harness_integration/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2021"
 publish = false
 
 [dependencies]
-mls-rs = { path = "..", default-features = false, features = ["std", "external_client", "external_commit", "state_update", "all_extensions"]}
+mls-rs = { path = "..", default-features = false, features = ["std", "external_client", "state_update"]}
 tonic = "0.7"
 prost = "0.10"
 tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
@@ -22,7 +22,7 @@ prior_epoch = [ "mls-rs/prior_epoch" ]
 out_of_order = [ "mls-rs/out_of_order", "private_message" ]
 psk = [ "mls-rs/psk" ]
 custom_proposal = [ "mls-rs/custom_proposal" ]
-by_ref_proposal = [ "mls-rs/by_ref_proposal", "mls-rs/external_proposal" ]
+by_ref_proposal = [ "mls-rs/by_ref_proposal" ]
 default = ["tree_index", "private_message", "prior_epoch", "out_of_order", "psk", "custom_proposal", "by_ref_proposal"]
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]