BUG29855733: Fix error during connection using charset and collation …

…combination

An error is raised when using the combination of utf8mb4 as charset and
utf8mb4_0900_bin as collation. The character id of this combination is 309,
which is greater than 1 byte specified in the handshake protocol.

This patch uses 1 extra byte from the reserved part of the payload, to
accommodate the necessary 2 bytes of this combination.

Tests were added/changed for regression.

CHANGES.txt

@@ -16,6 +16,7 @@ v8.0.17
 - WL#12735: Add README.rst and CONTRIBUTING.rst files
 - WL#12227: Indexing array fields
 - WL#12085: Support cursor prepared statements with C extension
+- BUG#29855733: Fix error during connection using charset and collation combination
 - BUG#29833590: Calling execute() should fetch active results
 - BUG#21072758: Support for connection attributes classic
 

lib/mysql/connector/protocol.py

@@ -98,8 +98,8 @@ def make_auth(self, handshake, username=None, password=None, database=None,
         except AttributeError:
             # Username is already bytes
             username_bytes = username
-        packet = struct.pack('<IIB{filler}{usrlen}sx'.format(
-            filler='x' * 23, usrlen=len(username_bytes)),
+        packet = struct.pack('<IIH{filler}{usrlen}sx'.format(
+            filler='x' * 22, usrlen=len(username_bytes)),
                              client_flags, max_allowed_packet, charset,
                              username_bytes)
 
@@ -140,7 +140,7 @@ def make_auth_ssl(self, charset=45, client_flags=0,
         """Make a SSL authentication packet"""
         return utils.int4store(client_flags) + \
                utils.int4store(max_allowed_packet) + \
-               utils.int1store(charset) + \
+               utils.int2store(charset) + \
                b'\x00' * 23
 
     def make_command(self, command, argument=None):

tests/test_bugs.py

@@ -5655,3 +5655,27 @@ def test_connection_args_compatibility(self):
 
         cnx = self.cnx.__class__(**config)
         cnx.close()
+
+
+@unittest.skipIf(tests.MYSQL_VERSION < (8, 0, 17),
+                 "MySQL 8.0.17+ is required for utf8mb4_0900_bin collation")
+class BugOra29855733(tests.MySQLConnectorTests):
+    """BUG#29855733: ERROR DURING THE CLASSIC CONNECTION WITH CHARSET AND
+    COLLATION SPECIFIED.
+    """
+    def setUp(self):
+        pass
+
+    def tearDown(self):
+        pass
+
+    @foreach_cnx()
+    def test_connection_collation_utf8mb4_0900_bin(self):
+        config = self.config.copy()
+        config["username"] = config["user"]
+        config["passwd"] = config["password"]
+        config["charset"] = "utf8mb4"
+        config["collation"] = "utf8mb4_0900_bin"
+
+        cnx = self.cnx.__class__(**config)
+        cnx.close()

tests/test_protocol.py

@@ -139,20 +139,20 @@ def test_make_auth_ssl(self):
             ({},
              b'\x00\x00\x00\x00\x00\x00\x00@-\x00\x00\x00\x00\x00\x00'
              b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
-             b'\x00\x00\x00'),
+             b'\x00\x00\x00\x00'),
             ({'charset': 8},
-             b'\x00\x00\x00\x00\x00\x00\x00\x40\x08\x00\x00\x00\x00\x00'
+             b'\x00\x00\x00\x00\x00\x00\x00@\x08\x00\x00\x00\x00\x00\x00'
              b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
              b'\x00\x00\x00\x00'),
             ({'client_flags': 240141},
              b'\r\xaa\x03\x00\x00\x00\x00@-\x00\x00\x00\x00\x00\x00\x00'
              b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
-             b'\x00\x00'),
+             b'\x00\x00\x00'),
             ({'charset': 8, 'client_flags': 240141,
               'max_allowed_packet': 2147483648},
-             b'\x0d\xaa\x03\x00\x00\x00\x00\x80\x08\x00\x00\x00\x00\x00'
+             b'\r\xaa\x03\x00\x00\x00\x00\x80\x08\x00\x00\x00\x00\x00'
              b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
-             b'\x00\x00\x00\x00'),
+             b'\x00\x00\x00\x00\x00'),
         ]
         for kwargs, exp in cases:
             self.assertEqual(exp, self._protocol.make_auth_ssl(**kwargs))