util.py: tighten protocol validation

electrumx/lib/util.py

@@ -256,16 +256,11 @@ def address_string(address):
     return fmt.format(host, port)
 
 
-VERSION_CLEANUP_REGEX = re.compile(r'([0-9.]*)')
-
-
 def protocol_tuple(s):
     '''Converts a protocol version number, such as "1.0" to a tuple (1, 0).
 
     If the version number is bad, (0, ) indicating version 0 is returned.'''
     try:
-        # clean up extra text at end of version e.g. '3.3.4CS' -> '3.3.4'
-        s = VERSION_CLEANUP_REGEX.match(s).group(1)
         return tuple(int(part) for part in s.split('.'))
     except (TypeError, ValueError, AttributeError):
         return (0, )

tests/lib/test_util.py

@@ -136,7 +136,6 @@ def test_protocol_tuple():
     assert util.protocol_tuple("0.1") == (0, 1)
     assert util.protocol_tuple("0.10") == (0, 10)
     assert util.protocol_tuple("2.5.3") == (2, 5, 3)
-    assert util.protocol_tuple("11.2.33ExtraXYZ") == (11, 2, 33)
 
 def test_version_string():
     assert util.version_string(()) == "0.0"