Avoid carrying rng

swap/src/protocol/alice.rs

@@ -198,6 +198,7 @@ impl Builder {
             self.execution_params.bitcoin_punish_timelock,
             redeem_address,
             punish_address,
+            rng,
         );
 
         Ok(AliceState::Started { amounts, state0 })

swap/src/protocol/alice/state.rs

@@ -16,7 +16,6 @@ use rand::{CryptoRng, RngCore};
 use serde::{Deserialize, Serialize};
 use sha2::Sha256;
 use std::fmt;
-use tracing::info;
 
 #[derive(Debug)]
 pub enum AliceState {
@@ -87,6 +86,7 @@ pub struct State0 {
     pub a: bitcoin::SecretKey,
     pub s_a: cross_curve_dleq::Scalar,
     pub v_a: monero::PrivateViewKey,
+    pub dleq_proof_s_a: cross_curve_dleq::Proof,
     #[serde(with = "::bitcoin::util::amount::serde::as_sat")]
     pub btc: bitcoin::Amount,
     pub xmr: monero::Amount,
@@ -98,7 +98,7 @@ pub struct State0 {
 
 impl State0 {
     #[allow(clippy::too_many_arguments)]
-    pub fn new(
+    pub fn new<R>(
         a: bitcoin::SecretKey,
         s_a: cross_curve_dleq::Scalar,
         v_a: monero::PrivateViewKey,
@@ -108,11 +108,18 @@ impl State0 {
         punish_timelock: Timelock,
         redeem_address: bitcoin::Address,
         punish_address: bitcoin::Address,
-    ) -> Self {
+        rng: &mut R,
+    ) -> Self
+    where
+        R: RngCore + CryptoRng,
+    {
+        let dleq_proof_s_a = cross_curve_dleq::Proof::new(rng, &s_a);
+
         Self {
             a,
             s_a,
             v_a,
+            dleq_proof_s_a,
             redeem_address,
             punish_address,
             btc,
@@ -122,17 +129,14 @@ impl State0 {
         }
     }
 
-    pub fn next_message<R: RngCore + CryptoRng>(&self, rng: &mut R) -> alice::Message0 {
-        info!("Producing first message");
-        let dleq_proof_s_a = cross_curve_dleq::Proof::new(rng, &self.s_a);
-
+    pub fn next_message(&self) -> alice::Message0 {
         alice::Message0 {
             A: self.a.public(),
             S_a_monero: monero::PublicKey::from_private_key(&monero::PrivateKey {
                 scalar: self.s_a.into_ed25519(),
             }),
             S_a_bitcoin: self.s_a.into_secp256k1().into(),
-            dleq_proof_s_a,
+            dleq_proof_s_a: self.dleq_proof_s_a.clone(),
             v_a: self.v_a,
             redeem_address: self.redeem_address.clone(),
             punish_address: self.punish_address.clone(),

swap/src/protocol/alice/steps.rs

@@ -23,7 +23,6 @@ use futures::{
     pin_mut,
 };
 use libp2p::PeerId;
-use rand::rngs::OsRng;
 use sha2::Sha256;
 use std::sync::Arc;
 use tokio::time::timeout;
@@ -62,7 +61,7 @@ pub async fn negotiate(
     )
     .await??;
 
-    let alice_message0 = state0.next_message(&mut OsRng);
+    let alice_message0 = state0.next_message();
     event_loop_handle
         .send_message0(channel, alice_message0)
         .await?;

swap/src/protocol/bob/state.rs

@@ -74,6 +74,7 @@ pub struct State0 {
     b: bitcoin::SecretKey,
     s_b: cross_curve_dleq::Scalar,
     v_b: monero::PrivateViewKey,
+    dleq_proof_s_b: cross_curve_dleq::Proof,
     #[serde(with = "::bitcoin::util::amount::serde::as_sat")]
     btc: bitcoin::Amount,
     xmr: monero::Amount,
@@ -97,6 +98,7 @@ impl State0 {
 
         let s_b = cross_curve_dleq::Scalar::random(rng);
         let v_b = monero::PrivateViewKey::new_random(rng);
+        let dleq_proof_s_b = cross_curve_dleq::Proof::new(rng, &s_b);
 
         Self {
             b,
@@ -104,6 +106,7 @@ impl State0 {
             v_b,
             btc,
             xmr,
+            dleq_proof_s_b,
             cancel_timelock,
             punish_timelock,
             refund_address,
@@ -111,16 +114,14 @@ impl State0 {
         }
     }
 
-    pub fn next_message<R: RngCore + CryptoRng>(&self, rng: &mut R) -> bob::Message0 {
-        let dleq_proof_s_b = cross_curve_dleq::Proof::new(rng, &self.s_b);
-
+    pub fn next_message(&self) -> bob::Message0 {
         bob::Message0 {
             B: self.b.public(),
             S_b_monero: monero::PublicKey::from_private_key(&monero::PrivateKey {
                 scalar: self.s_b.into_ed25519(),
             }),
             S_b_bitcoin: self.s_b.into_secp256k1().into(),
-            dleq_proof_s_b,
+            dleq_proof_s_b: self.dleq_proof_s_b.clone(),
             v_b: self.v_b,
             refund_address: self.refund_address.clone(),
         }

swap/src/protocol/bob/swap.rs

@@ -11,7 +11,6 @@ use crate::{
 };
 use anyhow::{bail, Result};
 use async_recursion::async_recursion;
-use rand::{rngs::OsRng, CryptoRng, RngCore};
 use std::sync::Arc;
 use tokio::select;
 use tracing::info;
@@ -44,7 +43,6 @@ pub async fn run_until(
         swap.db,
         swap.bitcoin_wallet,
         swap.monero_wallet,
-        OsRng,
         swap.swap_id,
         swap.execution_params,
     )
@@ -54,20 +52,16 @@ pub async fn run_until(
 // State machine driver for swap execution
 #[allow(clippy::too_many_arguments)]
 #[async_recursion]
-async fn run_until_internal<R>(
+async fn run_until_internal(
     state: BobState,
     is_target_state: fn(&BobState) -> bool,
     mut event_loop_handle: EventLoopHandle,
     db: Database,
     bitcoin_wallet: Arc<bitcoin::Wallet>,
     monero_wallet: Arc<monero::Wallet>,
-    mut rng: R,
     swap_id: Uuid,
     execution_params: ExecutionParams,
-) -> Result<BobState>
-where
-    R: RngCore + CryptoRng + Send,
-{
+) -> Result<BobState> {
     info!("Current state: {}", state);
     if is_target_state(&state) {
         Ok(state)
@@ -80,7 +74,6 @@ where
                     state0,
                     amounts,
                     &mut event_loop_handle,
-                    &mut rng,
                     bitcoin_wallet.clone(),
                 )
                 .await?;
@@ -95,7 +88,6 @@ where
                     db,
                     bitcoin_wallet,
                     monero_wallet,
-                    rng,
                     swap_id,
                     execution_params,
                 )
@@ -117,7 +109,6 @@ where
                     db,
                     bitcoin_wallet,
                     monero_wallet,
-                    rng,
                     swap_id,
                     execution_params,
                 )
@@ -170,7 +161,6 @@ where
                     db,
                     bitcoin_wallet,
                     monero_wallet,
-                    rng,
                     swap_id,
                     execution_params,
                 )
@@ -217,7 +207,6 @@ where
                     db,
                     bitcoin_wallet,
                     monero_wallet,
-                    rng,
                     swap_id,
                     execution_params,
                 )
@@ -260,7 +249,6 @@ where
                     db,
                     bitcoin_wallet,
                     monero_wallet,
-                    rng,
                     swap_id,
                     execution_params,
                 )
@@ -296,7 +284,6 @@ where
                     db,
                     bitcoin_wallet.clone(),
                     monero_wallet,
-                    rng,
                     swap_id,
                     execution_params,
                 )
@@ -318,7 +305,6 @@ where
                     db,
                     bitcoin_wallet,
                     monero_wallet,
-                    rng,
                     swap_id,
                     execution_params,
                 )
@@ -344,7 +330,6 @@ where
                     db,
                     bitcoin_wallet,
                     monero_wallet,
-                    rng,
                     swap_id,
                     execution_params,
                 )
@@ -376,7 +361,6 @@ where
                     db,
                     bitcoin_wallet,
                     monero_wallet,
-                    rng,
                     swap_id,
                     execution_params,
                 )
@@ -390,16 +374,12 @@ where
     }
 }
 
-pub async fn negotiate<R>(
+pub async fn negotiate(
     state0: crate::protocol::bob::state::State0,
     amounts: SwapAmounts,
     swarm: &mut EventLoopHandle,
-    mut rng: R,
     bitcoin_wallet: Arc<crate::bitcoin::Wallet>,
-) -> Result<bob::state::State2>
-where
-    R: RngCore + CryptoRng + Send,
-{
+) -> Result<bob::state::State2> {
     tracing::trace!("Starting negotiate");
     swarm
         .send_swap_request(SwapRequest {
@@ -411,7 +391,7 @@ where
     // argument.
     let _swap_response = swarm.recv_swap_response().await?;
 
-    swarm.send_message0(state0.next_message(&mut rng)).await?;
+    swarm.send_message0(state0.next_message()).await?;
     let msg0 = swarm.recv_message0().await?;
     let state1 = state0.receive(bitcoin_wallet.as_ref(), msg0).await?;