Multiple swaps with the same peer

- Swap-id is exchanged during execution setup. CLI (Bob) sends the swap-id to be used in his first message.
- Transfer poof and encryption signature messages include the swap-id so it can be properly associated with the correct swap.
- ASB: Encryption signatures are associated with swaps by swap-id, not peer-id.
- ASB: Transfer proofs are still associated to peer-ids (because they have to be sent to the respective peer), but the ASB can buffer multiple
- CLI: Incoming transfer proofs are checked for matching swap-id. If a transfer proof with a different swap-id than the current executing swap is received it will be ignored. We can change this to saving into the database.

Includes concurrent swap tests with the same Bob.

- One test that pauses and starts an additional swap after the transfer proof was received. Results in both swaps being redeemed after resuming the first swap.
- One test that pauses and starts an additional swap before the transfer proof is sent (just after BTC locked). Results in the second swap redeeming and the first swap being refunded (because the transfer proof on Bob's side is lost). Once we store transfer proofs that we receive during executing a different swap into the database both swaps should redeem.

Note that the monero harness was adapted to allow creating wallets with multiple outputs, which is needed for Alice.

swap/src/protocol/bob/state.rs

@@ -17,6 +17,7 @@ use serde::{Deserialize, Serialize};
 use sha2::Sha256;
 use sigma_fun::ext::dl_secp256k1_ed25519_eq::CrossCurveDLEQProof;
 use std::fmt;
+use uuid::Uuid;
 
 #[derive(Debug, Clone)]
 pub enum BobState {
@@ -69,6 +70,7 @@ impl fmt::Display for BobState {
 
 #[derive(Clone, Debug, PartialEq)]
 pub struct State0 {
+    swap_id: Uuid,
     b: bitcoin::SecretKey,
     s_b: monero::Scalar,
     S_b_monero: monero::PublicKey,
@@ -84,7 +86,9 @@ pub struct State0 {
 }
 
 impl State0 {
+    #[allow(clippy::too_many_arguments)]
     pub fn new<R: RngCore + CryptoRng>(
+        swap_id: Uuid,
         rng: &mut R,
         btc: bitcoin::Amount,
         xmr: monero::Amount,
@@ -101,6 +105,7 @@ impl State0 {
         let (dleq_proof_s_b, (S_b_bitcoin, S_b_monero)) = CROSS_CURVE_PROOF_SYSTEM.prove(&s_b, rng);
 
         Self {
+            swap_id,
             b,
             s_b,
             v_b,
@@ -120,6 +125,7 @@ impl State0 {
 
     pub fn next_message(&self) -> Message0 {
         Message0 {
+            swap_id: self.swap_id,
             B: self.b.public(),
             S_b_monero: self.S_b_monero,
             S_b_bitcoin: self.S_b_bitcoin,