Merge pull request #482 from gerlofvanek/electrum_fixes_2

Fix: Refund-path / Maturity checks.

basicswap/basicswap.py

@@ -5613,6 +5613,7 @@ class BasicSwap(BaseApp, BSXNetwork, UIApp):
                 )
 
                 # Check non-bip68 final
+                if not ci_from.useBackend():
                     try:
                         txid = ci_from.publishTx(bid.initiate_txn_refund)
                         self.log.error(
@@ -7686,7 +7687,16 @@ class BasicSwap(BaseApp, BSXNetwork, UIApp):
                         self.saveBidInSession(bid_id, bid, cursor, xmr_swap)
                         self.commitDB()
 
-                    if TxTypes.XMR_SWAP_A_LOCK_REFUND_SWIPE not in bid.txns:
+                    if (
+                        TxTypes.XMR_SWAP_A_LOCK_REFUND_SWIPE not in bid.txns
+                        and refund_tx.block_height is not None
+                        and ci_from.isCsvLockMature(
+                            offer.lock_type,
+                            xmr_offer.lock_time_2,
+                            refund_tx.block_height,
+                            refund_tx.block_time,
+                        )
+                    ):
                         try:
                             if self.haveDebugInd(
                                 bid.bid_id,
@@ -7782,6 +7792,13 @@ class BasicSwap(BaseApp, BSXNetwork, UIApp):
                 if (
                     len(xmr_swap.al_lock_refund_tx_sig) > 0
                     and len(xmr_swap.af_lock_refund_tx_sig) > 0
+                    and bid.xmr_a_lock_tx is not None
+                    and ci_from.isCsvLockMature(
+                        offer.lock_type,
+                        xmr_offer.lock_time_1,
+                        bid.xmr_a_lock_tx.block_height,
+                        bid.xmr_a_lock_tx.block_time,
+                    )
                 ):
 
                     try:
@@ -8213,6 +8230,19 @@ class BasicSwap(BaseApp, BSXNetwork, UIApp):
 
         return rv
 
+    def _isScriptRefundMature(self, ci, offer, refund_tx_bytes, parent_tx) -> bool:
+        refund_tx = ci.loadTx(refund_tx_bytes)
+        if offer.lock_type in (TxLockTypes.ABS_LOCK_BLOCKS, TxLockTypes.ABS_LOCK_TIME):
+            return ci.isAbsLockTimeMature(refund_tx.nLockTime)
+        if parent_tx is None or parent_tx.block_height is None:
+            return False
+        return ci.isCsvLockMature(
+            offer.lock_type,
+            refund_tx.vin[0].nSequence,
+            parent_tx.block_height,
+            parent_tx.block_time,
+        )
+
     def checkBidState(self, bid_id: bytes, bid, offer):
         # assert (self.mxDB.locked())
         # Return True to remove bid from in-progress list
@@ -8473,6 +8503,9 @@ class BasicSwap(BaseApp, BSXNetwork, UIApp):
         if (
             bid.getITxState() in (TxStates.TX_SENT, TxStates.TX_CONFIRMED)
             and bid.initiate_txn_refund is not None
+            and self._isScriptRefundMature(
+                ci_from, offer, bid.initiate_txn_refund, bid.initiate_tx
+            )
         ):
             try:
                 txid = ci_from.publishTx(bid.initiate_txn_refund)
@@ -8496,6 +8529,9 @@ class BasicSwap(BaseApp, BSXNetwork, UIApp):
         if (
             bid.getPTxState() in (TxStates.TX_SENT, TxStates.TX_CONFIRMED)
             and bid.participate_txn_refund is not None
+            and self._isScriptRefundMature(
+                ci_to, offer, bid.participate_txn_refund, bid.participate_tx
+            )
         ):
             try:
                 txid = ci_to.publishTx(bid.participate_txn_refund)
@@ -8511,7 +8547,7 @@ class BasicSwap(BaseApp, BSXNetwork, UIApp):
                 )
                 # State will update when spend is detected
             except Exception as ex:
-                if ci_to.isTxNonFinalError(str(ex)):
+                if ci_to.isTxNonFinalError(str(ex)) is False:
                     self.log.warning(
                         f"Error trying to submit participate refund txn: {ex}"
                     )

basicswap/interface/btc.py

@@ -502,6 +502,67 @@ class BTCInterface(Secp256k1Interface):
             return height
         return self.rpc("getblockcount")
 
+    def getChainMedianTime(self) -> int:
+        if self.useBackend():
+            import struct
+
+            backend = self.getBackend()
+            if not backend:
+                raise ValueError("No electrum backend available")
+            height = backend.getBlockHeight()
+            start = max(0, height - 10)
+            count = height - start + 1
+            result = backend._server.call("blockchain.block.headers", [start, count])
+            header_bytes = bytes.fromhex(result["hex"])
+            returned = result.get("count", count)
+            times = [
+                struct.unpack("<I", header_bytes[i * 80 + 68 : i * 80 + 72])[0]
+                for i in range(returned)
+            ]
+            times.sort()
+            return times[len(times) // 2]
+        return self.rpc("getblockchaininfo")["mediantime"]
+
+    def isCsvLockMature(
+        self,
+        lock_type: int,
+        encoded_sequence: int,
+        parent_block_height: Optional[int],
+        parent_block_time: Optional[int],
+        chain_height: Optional[int] = None,
+        chain_mtp: Optional[int] = None,
+    ) -> bool:
+        if parent_block_height is None or parent_block_height < 1:
+            return False
+        lock_value: int = self.decodeSequence(encoded_sequence)
+        if lock_type == TxLockTypes.SEQUENCE_LOCK_BLOCKS:
+            if chain_height is None:
+                chain_height = self.getChainHeight()
+            return chain_height + 1 >= parent_block_height + lock_value
+        if lock_type == TxLockTypes.SEQUENCE_LOCK_TIME:
+            if parent_block_time is None or parent_block_time < 1:
+                return False
+            if chain_mtp is None:
+                chain_mtp = self.getChainMedianTime()
+            return chain_mtp >= parent_block_time + lock_value
+        raise ValueError(f"Unknown lock type {lock_type}")
+
+    def isAbsLockTimeMature(
+        self,
+        nlocktime: int,
+        chain_height: Optional[int] = None,
+        chain_mtp: Optional[int] = None,
+    ) -> bool:
+        if nlocktime == 0:
+            return True
+        if nlocktime < 500000000:
+            if chain_height is None:
+                chain_height = self.getChainHeight()
+            return chain_height + 1 >= nlocktime
+        if chain_mtp is None:
+            chain_mtp = self.getChainMedianTime()
+        return chain_mtp >= nlocktime
+
     def getMempoolTx(self, txid):
         if self._connection_type == "electrum":
             backend = self.getBackend()
@@ -4370,11 +4431,11 @@ class BTCInterface(Secp256k1Interface):
         return "Transaction already in block chain" in err_str
 
     def isTxNonFinalError(self, err_str: str) -> bool:
+        err_lower = err_str.lower()
         return (
-            "non-BIP68-final" in err_str
-            or "non-final" in err_str
-            or "Missing inputs" in err_str
-            or "bad-txns-inputs-missingorspent" in err_str
+            "non-bip68-final" in err_lower
+            or "non-final" in err_lower
+            or "locktime requirement not satisfied" in err_lower
         )
 
     def combine_non_segwit_prevouts(self):