no_std and wasm support

.github/workflows/rust.yml

@@ -9,21 +9,34 @@ env:
   CARGO_NET_GIT_FETCH_WITH_CLI: true
 
 jobs:
-  build-and-test:
+  check-no-features:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v2
       with:
         cache-on-failure: "true"
-    - name: Build no features
-      run: cargo build -p round-based
-    - name: Build with tokio
-      run: cargo build -p round-based --features runtime-tokio
-    - name: Build with all features
-      run: cargo build -p round-based --all-features
-    - name: Run tests
-      run: cargo test --all-features
+    - name: cargo check
+      run: cargo check -p round-based --no-default-features
+  check:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - uses: Swatinem/rust-cache@v2
+      with:
+        cache-on-failure: "true"
+    - name: cargo check
+      run: cargo check -p round-based
+  check-all-features:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - uses: Swatinem/rust-cache@v2
+      with:
+        cache-on-failure: "true"
+    - name: cargo check
+      run: cargo check -p round-based --all-features
+
   check-fmt:
     runs-on: ubuntu-latest
     steps:
@@ -48,3 +61,16 @@ jobs:
         cache-on-failure: "true"
     - name: Run clippy
       run: cargo clippy --all --lib
+
+  build-wasm-nostd:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - uses: Swatinem/rust-cache@v2
+      with:
+        cache-on-failure: "true"
+    - name: Install wasm32-unknown-unknown toolchain
+      run: rustup target add wasm32-unknown-unknown
+    - name: Build on wasm32-unknown-unknown (no_std)
+      run:
+        (cd wasm/no_std && cargo build --target wasm32-unknown-unknown)

.gitignore

@@ -1,4 +1,5 @@
 /target
+/wasm/no_std/target
 .idea
 
 .cargo/

Cargo.toml

@@ -6,3 +6,6 @@ members = [
     "round-based-derive",
     "examples/random-generation-protocol",
 ]
+exclude = [
+    "wasm/no_std",
+]

examples/random-generation-protocol/Cargo.toml

@@ -7,18 +7,24 @@ publish = false
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-round-based = { path = "../../round-based", features = ["derive"]  }
+round-based = { path = "../../round-based", default-features = false, features = ["derive"] }
 
-tokio = { version = "1.15", features = ["rt"] }
-futures = "0.3"
-rand = "0.8"
-sha2 = "0.10"
-serde = { version = "1", features = ["derive"] }
+rand_core = { version = "0.6", default-features = false }
+sha2 = { version = "0.10", default-features = false }
+serde = { version = "1", default-features = false, features = ["derive"] }
+
+displaydoc = { version = "0.2", default-features = false }
+thiserror = { version = "1", optional = true }
+
+# We don't use it directy, but we need to enable `serde` feature
 generic-array = { version = "0.14", features = ["serde"] }
-thiserror = "1"
 
 [dev-dependencies]
 round-based = { path = "../../round-based", features = ["derive", "dev"]  }
 tokio = { version = "1.15", features = ["macros", "rt"] }
+futures = "0.3"
 hex = "0.4"
-rand_chacha = "0.3"
+rand_dev = "0.1"
+
+[features]
+std = ["thiserror"]

examples/random-generation-protocol/src/lib.rs

@@ -1,31 +1,53 @@
-use futures::SinkExt;
-use rand::RngCore;
+//! Simple protocol in which parties cooperate to generate randomness
+
+#![no_std]
+#![forbid(unused_crate_dependencies, missing_docs)]
+
+#[cfg(feature = "std")]
+extern crate std;
+
+extern crate alloc;
+
+mod _unused_deps {
+    // We don't use it directy, but we need to enable `serde` feature
+    use generic_array as _;
+}
+
+use alloc::{vec, vec::Vec};
+
 use serde::{Deserialize, Serialize};
 use sha2::{digest::Output, Digest, Sha256};
-use thiserror::Error;
 
 use round_based::rounds_router::{
     simple_store::{RoundInput, RoundInputError},
     CompleteRoundError, RoundsRouter,
 };
-use round_based::{Delivery, Mpc, MpcParty, MsgId, Outgoing, PartyIndex, ProtocolMessage};
+use round_based::{Delivery, Mpc, MpcParty, MsgId, Outgoing, PartyIndex, ProtocolMessage, SinkExt};
 
+/// Protocol message
 #[derive(Clone, Debug, PartialEq, ProtocolMessage, Serialize, Deserialize)]
 pub enum Msg {
+    /// Round 1
     CommitMsg(CommitMsg),
+    /// Round 2
     DecommitMsg(DecommitMsg),
 }
 
+/// Message from round 1
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub struct CommitMsg {
+    /// Party commitment
     pub commitment: Output<Sha256>,
 }
 
+/// Message from round 2
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub struct DecommitMsg {
+    /// Randomness generated by party
     pub randomness: [u8; 32],
 }
 
+/// Carries out the randomness generation protocol
 pub async fn protocol_of_random_generation<R, M>(
     party: M,
     i: PartyIndex,
@@ -34,7 +56,7 @@ pub async fn protocol_of_random_generation<R, M>(
 ) -> Result<[u8; 32], Error<M::ReceiveError, M::SendError>>
 where
     M: Mpc<ProtocolMessage = Msg>,
-    R: RngCore,
+    R: rand_core::RngCore,
 {
     let MpcParty { delivery, .. } = party.into_party();
     let (incoming, mut outgoing) = delivery.split();
@@ -109,48 +131,66 @@ where
     }
 }
 
-#[derive(Debug, Error)]
+/// Protocol error
+#[derive(Debug, displaydoc::Display)]
+#[cfg_attr(feature = "std", derive(thiserror::Error))]
 pub enum Error<RecvErr, SendErr> {
-    #[error("send a message at round 1")]
-    Round1Send(#[source] SendErr),
-    #[error("receive messages at round 1")]
-    Round1Receive(#[source] CompleteRoundError<RoundInputError, RecvErr>),
-    #[error("send a message at round 2")]
-    Round2Send(#[source] SendErr),
-    #[error("receive messages at round 2")]
-    Round2Receive(#[source] CompleteRoundError<RoundInputError, RecvErr>),
-
-    #[error("malicious parties: {guilty_parties:?}")]
-    PartiesOpenedRandomnessDoesntMatchCommitment { guilty_parties: Vec<Blame> },
+    /// Couldn't send a message in the first round
+    #[displaydoc("send a message at round 1")]
+    Round1Send(#[cfg_attr(feature = "std", source)] SendErr),
+    /// Couldn't receive a message in the first round
+    #[displaydoc("receive messages at round 1")]
+    Round1Receive(
+        #[cfg_attr(feature = "std", source)] CompleteRoundError<RoundInputError, RecvErr>,
+    ),
+    /// Couldn't send a message in the second round
+    #[displaydoc("send a message at round 2")]
+    Round2Send(#[cfg_attr(feature = "std", source)] SendErr),
+    /// Couldn't receive a message in the second round
+    #[displaydoc("receive messages at round 2")]
+    Round2Receive(
+        #[cfg_attr(feature = "std", source)] CompleteRoundError<RoundInputError, RecvErr>,
+    ),
+
+    /// Some of the parties cheated
+    #[displaydoc("malicious parties: {guilty_parties:?}")]
+    PartiesOpenedRandomnessDoesntMatchCommitment {
+        /// List of cheated parties
+        guilty_parties: Vec<Blame>,
+    },
 }
 
+/// Blames a party in cheating during the protocol
 #[derive(Debug)]
 pub struct Blame {
+    /// Index of the cheated party
     pub guilty_party: PartyIndex,
+    /// ID of the message that party sent in the first round
     pub commitment_msg: MsgId,
+    /// ID of the message that party sent in the second round
     pub decommitment_msg: MsgId,
 }
 
 #[cfg(test)]
 mod tests {
-    use rand::SeedableRng;
-    use rand_chacha::ChaCha20Rng;
+    use alloc::vec;
 
     use round_based::simulation::Simulation;
 
     use super::{protocol_of_random_generation, Msg};
 
     #[tokio::test]
     async fn main() {
+        let mut rng = rand_dev::DevRng::new();
+
         let n: u16 = 5;
 
         let mut simulation = Simulation::<Msg>::new();
         let mut party_output = vec![];
 
         for i in 0..n {
             let party = simulation.add_party();
-            let rng = ChaCha20Rng::from_entropy();
-            let output = protocol_of_random_generation(party, i, n, rng);
+            let output = protocol_of_random_generation(party, i, n, rng.fork());
             party_output.push(output);
         }
 
@@ -161,6 +201,6 @@ mod tests {
             assert_eq!(output[0], output[usize::from(i)]);
         }
 
-        println!("Output randomness: {}", hex::encode(output[0]));
+        std::println!("Output randomness: {}", hex::encode(output[0]));
     }
 }

round-based/CHANGELOG.md

@@ -1,3 +1,8 @@
+## v0.3.0
+* Add no_std and wasm support [#6]
+
+[#6]: https://github.com/dfns/round-based/pull/6
+
 ## v0.2.2
 
 * fix: correct handling of stores that need no messages in RoundsRouter [#4]