Fix a bug where a socket connection to "bsv.aftrek.org" is successful… (

#1132)

* Fix a bug where a socket connection to "bsv.aftrek.org" is successfully established but on protocol negotiation, the result is "None"

- This crashes the entire asyncio event loop with "TypeError: cannot unpack non-iterable NoneType object"
- Catch the raised TypeError to avoid crashing the asyncio event loop.

* Remove hardcoding of the blacklist attribute

- Servers will now be blacklisted if `DisconnectSessionError` is raised with blacklist=True

* Add unittest for various bad inputs to `protocol_tuple`

- Added type assertions to `_negotiate_protocol` handler to ensure bad responses from a misbehaving ElectrumX server are appropriately caught.

.gitignore

@@ -61,5 +61,5 @@ Pipfile
 Pipfile.lock
 
 # local data directories
-electrum_sv_data/regtest/*
+electrum_sv_data/*
 instance_*

electrumsv/network.py

@@ -153,7 +153,7 @@ class DisconnectSessionError(Exception):
 
     def __init__(self, reason, *, blacklist=False):
         super().__init__(reason)
-        self.blacklist = False
+        self.blacklist = blacklist
 
 
 class SVServerState:
@@ -461,11 +461,14 @@ async def _negotiate_protocol(self):
         args = (PACKAGE_VERSION, [ version_string(PROTOCOL_MIN), version_string(PROTOCOL_MAX) ])
         try:
             server_string, protocol_string = await self.send_request(method, args)
+            assert isinstance(server_string, str)
+            assert isinstance(protocol_string, str)
             self.logger.debug(f'server string: {server_string}')
             self.logger.debug(f'negotiated protocol: {protocol_string}')
             self.ptuple = protocol_tuple(protocol_string)
+            assert len(self.ptuple) in (2, 3)
             assert PROTOCOL_MIN <= self.ptuple <= PROTOCOL_MAX
-        except (AssertionError, ValueError) as e:
+        except (AssertionError, TypeError, ValueError) as e:
             raise DisconnectSessionError(f'{method} failed: {e}', blacklist=True)
 
     async def _get_checkpoint_headers(self):

electrumsv/tests/test_util.py

@@ -1,7 +1,7 @@
 import pytest
 import unittest
 
-from electrumsv.util import format_satoshis, get_identified_release_signers
+from electrumsv.util import format_satoshis, get_identified_release_signers, protocol_tuple
 from electrumsv.util.cache import LRUCache
 
 from .conftest import get_tx_datacarrier_size, get_tx_small_size
@@ -12,6 +12,38 @@
 
 
 class TestUtil(unittest.TestCase):
+    def test_protocol_tuple(self):
+        bad_input1 = ""
+        bad_input2 = "..."
+        bad_input3 = 100
+        bad_input4 = [1, 4, 2]
+        bad_input5 = 1.4
+        bad_input6 = (1, 4, 2)
+        bad_input7 = "letters"
+        bad_input8 = None
+
+        good_input1 = "1.4.2"
+        good_input2 = "1.4"
+        with pytest.raises(ValueError):
+            protocol_tuple(bad_input1)
+        with pytest.raises(ValueError):
+            protocol_tuple(bad_input2)
+        with pytest.raises(ValueError):
+            protocol_tuple(bad_input3)
+        with pytest.raises(ValueError):
+            protocol_tuple(bad_input4)
+        with pytest.raises(ValueError):
+            protocol_tuple(bad_input5)
+        with pytest.raises(ValueError):
+            protocol_tuple(bad_input6)
+        with pytest.raises(ValueError):
+            protocol_tuple(bad_input7)
+        with pytest.raises(ValueError):
+            protocol_tuple(bad_input8)
+
+        assert protocol_tuple(good_input1) == (1, 4, 2)
+        assert protocol_tuple(good_input2) == (1, 4)
+
     def test_format_satoshis(self):
         result = format_satoshis(1234)
         expected = "0.00001234"