Fix exception thrown when signing without open wallet (#710)

Fix silent failing when trying to sign with a multi-sig key not in the wallet
Fix transaction retry failure due to not cleaning up internal KnownHashes on add failure
Fix ghost thread throwing exceptions when trying to add to a non existing wallet
Fix signatures sorting on encoded ECPoint bytes values instead of a combination of ECPoint.X and ECPoint.Y preventing CHECKMULTISIG to pass

CHANGELOG.rst

@@ -9,6 +9,7 @@ All notable changes to this project are documented in this file.
 - Fix confirmed tx not being purged from mempool `#703 </~https://github.com/CityOfZion/neo-python/issues/703>`_
 - Fix bootstrap thread joining failure on Ubuntu systems
 - Make bootstrap lookup dynamic such that users don't have to update their configs from here on forward
+- Fix various issues related to signing multi-signature transactions
 - Move some warnings and 'expected' errors to `DEBUG` level to avoid logging to console by default
 - Empty VerificationScripts for deployed contracts now work as intended
 - Fix RPC's ``getaccountstate`` response schema to match ``neo-cli`` `#714 </~https://github.com/CityOfZion/neo-python/issues/714>`

neo/Network/NodeLeader.py

@@ -321,6 +321,12 @@ def Relay(self, inventory):
 
         elif type(inventory) is Transaction or issubclass(type(inventory), Transaction):
             if not self.AddTransaction(inventory):
+                # if we fail to add the transaction for whatever reason, remove it from the known hashes list or we cannot retry the same transaction again
+                try:
+                    self.KnownHashes.remove(inventory.Hash.ToBytes())
+                except ValueError:
+                    # it not found
+                    pass
                 return False
         else:
             # consensus

neo/Prompt/Commands/Send.py

@@ -176,7 +176,6 @@ def process_transaction(wallet, contract_tx, scripthash_from=None, scripthash_ch
             signer_contract = wallet.GetContract(standard_contract)
 
         if not signer_contract.IsMultiSigContract and owners is None:
-
             data = standard_contract.Data
             tx.Attributes = [TransactionAttribute(usage=TransactionAttributeUsage.Script,
                                                   data=data)]
@@ -201,7 +200,7 @@ def process_transaction(wallet, contract_tx, scripthash_from=None, scripthash_ch
 
             tx.scripts = context.GetScripts()
 
-#            print("will send tx: %s " % json.dumps(tx.ToJson(),indent=4))
+            #            print("will send tx: %s " % json.dumps(tx.ToJson(),indent=4))
 
             relayed = NodeLeader.Instance().Relay(tx)
 
@@ -228,7 +227,6 @@ def process_transaction(wallet, contract_tx, scripthash_from=None, scripthash_ch
 
 
 def parse_and_sign(wallet, jsn):
-
     try:
         context = ContractParametersContext.FromJson(jsn)
         if context is None:

neo/SmartContract/ContractParameterContext.py

@@ -10,6 +10,7 @@
 from neo.VM import OpCode
 from neo.Core.Witness import Witness
 from neo.logging import log_manager
+from neocore.Cryptography.ECCurve import ECDSA
 
 logger = log_manager.getLogger('vm')
 
@@ -158,26 +159,30 @@ def AddSignature(self, contract, pubkey, signature):
             elif pubkey.encode_point(True) in item.Signatures:
                 return False
 
+            ecdsa = ECDSA.secp256r1()
             points = []
             temp = binascii.unhexlify(contract.Script)
             ms = MemoryStream(binascii.unhexlify(contract.Script))
             reader = BinaryReader(ms)
             numr = reader.ReadUInt8()
             while reader.ReadUInt8() == 33:
-                points.append(binascii.hexlify(reader.ReadBytes(33)))
+                ecpoint = ecdsa.ec.decode_from_hex(binascii.hexlify(reader.ReadBytes(33)).decode())
+                points.append(ecpoint)
             ms.close()
 
-            if pubkey.encode_point(True) not in points:
+            if pubkey not in points:
                 return False
 
             item.Signatures[pubkey.encode_point(True).decode()] = binascii.hexlify(signature)
 
             if len(item.Signatures) == len(contract.ParameterList):
+
                 i = 0
                 points.sort(reverse=True)
                 for k in points:
-                    if k.decode() in item.Signatures:
-                        if self.Add(contract, i, item.Signatures[k.decode()]) is None:
+                    pubkey = k.encode_point(True).decode()
+                    if pubkey in item.Signatures:
+                        if self.Add(contract, i, item.Signatures[pubkey]) is None:
                             raise Exception("Invalid operation")
                         i += 1
                 item.Signatures = None

neo/Wallets/Wallet.py

@@ -1183,6 +1183,7 @@ def Sign(self, context):
 
             contract = self.GetContract(hash)
             if contract is None:
+                logger.info(f"Cannot find key belonging to script_hash {hash}. Make sure the source address you're trying to sign the transaction for is imported in the wallet.")
                 continue
 
             key = self.GetKeyByScriptHash(hash)

neo/bin/prompt.py

@@ -304,13 +304,15 @@ def do_create(self, arguments):
     def start_wallet_loop(self):
         if self.wallet_loop_deferred:
             self.stop_wallet_loop()
-        walletdb_loop = task.LoopingCall(self.Wallet.ProcessBlocks)
-        self.wallet_loop_deferred = walletdb_loop.start(1)
+        self.walletdb_loop = task.LoopingCall(self.Wallet.ProcessBlocks)
+        self.wallet_loop_deferred = self.walletdb_loop.start(1)
         self.wallet_loop_deferred.addErrback(self.on_looperror)
 
     def stop_wallet_loop(self):
         self.wallet_loop_deferred.cancel()
         self.wallet_loop_deferred = None
+        if self.walletdb_loop and self.walletdb_loop.running:
+            self.walletdb_loop.stop()
 
     def do_close_wallet(self):
         if self.Wallet:
@@ -559,6 +561,8 @@ def do_send_many(self, arguments):
             process_transaction(self.Wallet, contract_tx=framework[0], scripthash_from=framework[1], scripthash_change=framework[2], fee=framework[3], owners=framework[4], user_tx_attributes=framework[5])
 
     def do_sign(self, arguments):
+        if not self.Wallet:
+            print("Please open a wallet before trying to sign")
         jsn = get_arg(arguments)
         parse_and_sign(self.Wallet, jsn)