Explicitly set messagemagic string for Particl v27

basicswap/interface/btc.py

@@ -1981,6 +1981,15 @@ class BTCInterface(Secp256k1Interface):
             sum_unspent += self.make_int(o["amount"])
         return sum_unspent
 
+    def signMessage(self, address: str, message: str) -> str:
+        return self.rpc_wallet(
+            "signmessage",
+            [address, message],
+        )
+
+    def signMessageWithKey(self, key_wif: str, message: str) -> str:
+        return self.rpc("signmessagewithprivkey", [key_wif, message])
+
     def getProofOfFunds(self, amount_for, extra_commit_bytes):
         # TODO: Lock unspent and use same output/s to fund bid
         unspent_addr = self.getUnspentsByAddr()
@@ -1998,6 +2007,7 @@ class BTCInterface(Secp256k1Interface):
         self._log.debug(f"sign_for_addr {sign_for_addr}")
 
         funds_addr: str = sign_for_addr
+
         if (
             self.using_segwit()
         ):  # TODO: Use isSegwitAddress when scantxoutset can use combo
@@ -2006,6 +2016,7 @@ class BTCInterface(Secp256k1Interface):
             sign_for_addr = self.pkh_to_address(pkh)
             self._log.debug(f"sign_for_addr converted {sign_for_addr}")
 
+        sign_message: str = sign_for_addr + "_swap_proof_" + extra_commit_bytes.hex()
         if self._use_descriptors:
             # https://github.com/bitcoin/bitcoin/issues/10542
             # https://github.com/bitcoin/bitcoin/issues/26046
@@ -2022,7 +2033,6 @@ class BTCInterface(Secp256k1Interface):
                 ],
             )
             hdkeypath = addr_info["hdkeypath"]
-
             sign_for_address_key = None
             for descriptor in priv_keys["descriptors"]:
                 if descriptor["active"] is False or descriptor["internal"] is True:
@@ -2043,22 +2053,10 @@ class BTCInterface(Secp256k1Interface):
                 sign_for_address_key = self.encodeKey(ek._key)
                 break
             assert sign_for_address_key is not None
-            signature = self.rpc(
-                "signmessagewithprivkey",
-                [
-                    sign_for_address_key,
-                    sign_for_addr + "_swap_proof_" + extra_commit_bytes.hex(),
-                ],
-            )
+            signature = self.signMessageWithKey(sign_for_address_key, sign_message)
             del priv_keys
         else:
-            signature = self.rpc_wallet(
-                "signmessage",
-                [
-                    sign_for_addr,
-                    sign_for_addr + "_swap_proof_" + extra_commit_bytes.hex(),
-                ],
-            )
+            signature = self.signMessage(sign_for_addr, sign_message)
 
         prove_utxos = []  # TODO: Send specific utxos
         return (sign_for_addr, signature, prove_utxos)