Bitcoin transaction published state

This improves the error handling on the ASB.
Once the Bitcoin redeem transaction is seen in mempool, the state machine cannot transition to a cancel scenario anymore because at that point the CLI will have redeemed the Monero.
The additional state then waits for transaction finality.

CHANGELOG.md

@@ -45,6 +45,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   3. ASB is running in resume-only mode and does not accept incoming swap requests
 - An issue where the monero daemon port used by the `monero-wallet-rpc` could not be specified.
   The CLI parameter `--monero-daemon-host` was changed to `--monero-daemon-address` where host and port have to be specified.
+- An issue where an ASB redeem scenario can transition to a cancel and publish scenario that will fail.
+  This is a breaking change for the ASB, because it introduces a new state into the database.
 
 ### Changed
 

swap/src/database/alice.rs

@@ -39,6 +39,9 @@ pub enum Alice {
         encrypted_signature: EncryptedSignature,
         state3: alice::State3,
     },
+    BtcRedeemTransactionPublished {
+        state3: alice::State3,
+    },
     CancelTimelockExpired {
         monero_wallet_restore_blockheight: BlockHeight,
         transfer_proof: TransferProof,
@@ -119,6 +122,11 @@ impl From<&AliceState> for Alice {
                 state3: state3.as_ref().clone(),
                 encrypted_signature: *encrypted_signature.clone(),
             },
+            AliceState::BtcRedeemTransactionPublished { state3 } => {
+                Alice::BtcRedeemTransactionPublished {
+                    state3: state3.as_ref().clone(),
+                }
+            }
             AliceState::BtcRedeemed => Alice::Done(AliceEndState::BtcRedeemed),
             AliceState::BtcCancelled {
                 monero_wallet_restore_blockheight,
@@ -212,6 +220,11 @@ impl From<Alice> for AliceState {
                 state3: Box::new(state),
                 encrypted_signature: Box::new(encrypted_signature),
             },
+            Alice::BtcRedeemTransactionPublished { state3 } => {
+                AliceState::BtcRedeemTransactionPublished {
+                    state3: Box::new(state3),
+                }
+            }
             Alice::CancelTimelockExpired {
                 monero_wallet_restore_blockheight,
                 transfer_proof,
@@ -271,12 +284,15 @@ impl Display for Alice {
             Alice::XmrLockTransferProofSent { .. } => {
                 f.write_str("Monero lock transfer proof sent")
             }
+            Alice::EncSigLearned { .. } => f.write_str("Encrypted signature learned"),
+            Alice::BtcRedeemTransactionPublished { .. } => {
+                f.write_str("Bitcoin redeem transaction published")
+            }
             Alice::CancelTimelockExpired { .. } => f.write_str("Cancel timelock is expired"),
             Alice::BtcCancelled { .. } => f.write_str("Bitcoin cancel transaction published"),
             Alice::BtcPunishable { .. } => f.write_str("Bitcoin punishable"),
             Alice::BtcRefunded { .. } => f.write_str("Monero refundable"),
             Alice::Done(end_state) => write!(f, "Done: {}", end_state),
-            Alice::EncSigLearned { .. } => f.write_str("Encrypted signature learned"),
         }
     }
 }

swap/src/protocol/alice/recovery/cancel.rs

@@ -34,6 +34,9 @@ pub async fn cancel(
             (monero_wallet_restore_blockheight, transfer_proof, state3)
         }
 
+        // The redeem transaction was already published, it is not safe to cancel anymore
+        AliceState::BtcRedeemTransactionPublished { .. } => bail!(" The redeem transaction was already published, it is not safe to cancel anymore"),
+
         // The cancel tx was already published, but Alice not yet in final state
         AliceState::BtcCancelled { .. }
         | AliceState::BtcRefunded { .. }
@@ -43,7 +46,7 @@ pub async fn cancel(
         | AliceState::BtcRedeemed
         | AliceState::XmrRefunded
         | AliceState::BtcPunished
-        | AliceState::SafelyAborted => bail!("Cannot cancel swap {} because it is in state {} which is not cancelable", swap_id, state),
+        | AliceState::SafelyAborted => bail!("Swap is is in state {} which is not cancelable", state),
     };
 
     tracing::info!(%swap_id, "Trying to manually cancel swap");

swap/src/protocol/alice/recovery/punish.rs

@@ -50,7 +50,8 @@ pub async fn punish(
             }
 
             // If the swap was refunded it cannot be punished
-            AliceState::BtcRefunded {..}
+            AliceState::BtcRedeemTransactionPublished { .. }
+            | AliceState::BtcRefunded {..}
             // Alice already in final state
             | AliceState::BtcRedeemed
             | AliceState::XmrRefunded

swap/src/protocol/alice/recovery/redeem.rs

@@ -50,19 +50,39 @@ pub async fn redeem(
             let redeem_tx = state3.signed_redeem_transaction(*encrypted_signature)?;
             let (txid, subscription) = bitcoin_wallet.broadcast(redeem_tx, "redeem").await?;
 
+            subscription.wait_until_seen().await?;
+
+            let state = AliceState::BtcRedeemTransactionPublished { state3 };
+            let db_state = (&state).into();
+            db.insert_latest_state(swap_id, Swap::Alice(db_state))
+                .await?;
+
             if let Finality::Await = finality {
                 subscription.wait_until_final().await?;
             }
 
             let state = AliceState::BtcRedeemed;
             let db_state = (&state).into();
-
             db.insert_latest_state(swap_id, Swap::Alice(db_state))
                 .await?;
 
             Ok((txid, state))
         }
+        AliceState::BtcRedeemTransactionPublished { state3 } => {
+            let subscription = bitcoin_wallet.subscribe_to(state3.tx_redeem()).await;
+            if let Finality::Await = finality {
+                subscription.wait_until_final().await?;
+            }
 
+            let state = AliceState::BtcRedeemed;
+            let db_state = (&state).into();
+            db.insert_latest_state(swap_id, Swap::Alice(db_state))
+                .await?;
+
+            let txid = state3.tx_redeem().txid();
+
+            Ok((txid, state))
+        }
         AliceState::Started { .. }
         | AliceState::BtcLocked { .. }
         | AliceState::XmrLockTransactionSent { .. }

swap/src/protocol/alice/recovery/refund.rs

@@ -56,7 +56,8 @@ pub async fn refund(
             }
 
             // Alice already in final state
-            AliceState::BtcRedeemed
+            AliceState::BtcRedeemTransactionPublished { .. }
+            | AliceState::BtcRedeemed
             | AliceState::XmrRefunded
             | AliceState::BtcPunished
             | AliceState::SafelyAborted => bail!(Error::SwapNotRefundable(state)),

swap/src/protocol/alice/recovery/safely_abort.rs

@@ -22,6 +22,7 @@ pub async fn safely_abort(swap_id: Uuid, db: Arc<Database>) -> Result<AliceState
         | AliceState::XmrLocked { .. }
         | AliceState::XmrLockTransferProofSent { .. }
         | AliceState::EncSigLearned { .. }
+        | AliceState::BtcRedeemTransactionPublished { .. }
         | AliceState::CancelTimelockExpired { .. }
         | AliceState::BtcCancelled { .. }
         | AliceState::BtcRefunded { .. }

swap/src/protocol/alice/state.rs

@@ -1,6 +1,6 @@
 use crate::bitcoin::{
     current_epoch, CancelTimelock, ExpiredTimelocks, PunishTimelock, Transaction, TxCancel,
-    TxPunish, TxRefund, Txid,
+    TxPunish, TxRedeem, TxRefund, Txid,
 };
 use crate::env::Config;
 use crate::monero::wallet::{TransferRequest, WatchRequest};
@@ -45,6 +45,9 @@ pub enum AliceState {
         encrypted_signature: Box<bitcoin::EncryptedSignature>,
         state3: Box<State3>,
     },
+    BtcRedeemTransactionPublished {
+        state3: Box<State3>,
+    },
     BtcRedeemed,
     BtcCancelled {
         monero_wallet_restore_blockheight: BlockHeight,
@@ -83,6 +86,9 @@ impl fmt::Display for AliceState {
                 write!(f, "xmr lock transfer proof sent")
             }
             AliceState::EncSigLearned { .. } => write!(f, "encrypted signature is learned"),
+            AliceState::BtcRedeemTransactionPublished { .. } => {
+                write!(f, "bitcoin redeem transaction published")
+            }
             AliceState::BtcRedeemed => write!(f, "btc is redeemed"),
             AliceState::BtcCancelled { .. } => write!(f, "btc is cancelled"),
             AliceState::BtcRefunded { .. } => write!(f, "btc is refunded"),
@@ -449,6 +455,10 @@ impl State3 {
         bitcoin::TxRefund::new(&self.tx_cancel(), &self.refund_address, self.tx_refund_fee)
     }
 
+    pub fn tx_redeem(&self) -> TxRedeem {
+        TxRedeem::new(&self.tx_lock, &self.redeem_address, self.tx_redeem_fee)
+    }
+
     pub fn extract_monero_private_key(
         &self,
         published_refund_tx: bitcoin::Transaction,

swap/src/protocol/alice/swap.rs

@@ -204,10 +204,10 @@ where
                 let tx_lock_status = bitcoin_wallet.subscribe_to(state3.tx_lock.clone()).await;
                 match state3.signed_redeem_transaction(*encrypted_signature) {
                     Ok(tx) => match bitcoin_wallet.broadcast(tx, "redeem").await {
-                        Ok((_, subscription)) => match subscription.wait_until_final().await {
-                            Ok(_) => AliceState::BtcRedeemed,
+                        Ok((_, subscription)) => match subscription.wait_until_seen().await {
+                            Ok(_) => AliceState::BtcRedeemTransactionPublished { state3 },
                             Err(e) => {
-                                bail!("Waiting for Bitcoin transaction finality failed with {}! The redeem transaction was published, but it is not ensured that the transaction was included! You're screwed.", e)
+                                bail!("Waiting for Bitcoin redeem transaction to be in mempool failed with {}! The redeem transaction was published, but it is not ensured that the transaction was included! You're screwed.", e)
                             }
                         },
                         Err(error) => {
@@ -247,6 +247,16 @@ where
                 state3,
             },
         },
+        AliceState::BtcRedeemTransactionPublished { state3 } => {
+            let subscription = bitcoin_wallet.subscribe_to(state3.tx_redeem()).await;
+
+            match subscription.wait_until_final().await {
+                Ok(_) => AliceState::BtcRedeemed,
+                Err(e) => {
+                    bail!("The Bitcoin redeem transaction was seen in mempool, but waiting for finality timed out with {}. Manual investigation might be needed to ensure that the transaction was included.", e)
+                }
+            }
+        }
         AliceState::CancelTimelockExpired {
             monero_wallet_restore_blockheight,
             transfer_proof,