SSL Support (plus mysql_clear_password plugin for RDS) (#280)

* Added SSL Support again

* Issue #265 - _process_auth implementation

* Added cleartext plugin test

aiomysql/connection.py

@@ -56,7 +56,7 @@ def connect(host="localhost", user=None, password="",
             client_flag=0, cursorclass=Cursor, init_command=None,
             connect_timeout=None, read_default_group=None,
             no_delay=None, autocommit=False, echo=False,
-            local_infile=False, loop=None):
+            local_infile=False, loop=None, ssl=None, auth_plugin=''):
     """See connections.Connection.__init__() for information about
     defaults."""
     coro = _connect(host=host, user=user, password=password, db=db,
@@ -68,7 +68,8 @@ def connect(host="localhost", user=None, password="",
                     connect_timeout=connect_timeout,
                     read_default_group=read_default_group,
                     no_delay=no_delay, autocommit=autocommit, echo=echo,
-                    local_infile=local_infile, loop=loop)
+                    local_infile=local_infile, loop=loop, ssl=ssl,
+                    auth_plugin=auth_plugin)
     return _ConnectionContextManager(coro)
 
 
@@ -93,7 +94,7 @@ def __init__(self, host="localhost", user=None, password="",
                  client_flag=0, cursorclass=Cursor, init_command=None,
                  connect_timeout=None, read_default_group=None,
                  no_delay=None, autocommit=False, echo=False,
-                 local_infile=False, loop=None):
+                 local_infile=False, loop=None, ssl=None, auth_plugin=''):
         """
         Establish a connection to the MySQL database. Accepts several
         arguments:
@@ -164,6 +165,9 @@ def __init__(self, host="localhost", user=None, password="",
         self._no_delay = no_delay
         self._echo = echo
         self._last_usage = self._loop.time()
+        self._client_auth_plugin = auth_plugin
+        self._server_auth_plugin = ""
+        self._auth_plugin_used = ""
 
         self._unix_socket = unix_socket
         if charset:
@@ -176,6 +180,10 @@ def __init__(self, host="localhost", user=None, password="",
         if use_unicode is not None:
             self.use_unicode = use_unicode
 
+        self._ssl_context = ssl
+        if ssl:
+            client_flag |= CLIENT.SSL
+
         self._encoding = charset_by_name(self._charset).encoding
 
         if local_infile:
@@ -209,8 +217,6 @@ def __init__(self, host="localhost", user=None, password="",
         # user
         self._close_reason = None
 
-        self._auth_plugin_name = ""
-
     @property
     def host(self):
         """MySQL server IP address or name"""
@@ -663,6 +669,31 @@ def _request_authentication(self):
         if self.user is None:
             raise ValueError("Did not specify a username")
 
+        if self._ssl_context:
+            # capablities, max packet, charset
+            data = struct.pack('<IIB', self.client_flag, 16777216, 33)
+            data += b'\x00' * (32 - len(data))
+
+            self.write_packet(data)
+
+            # Stop sending events to data_received
+            self._writer.transport.pause_reading()
+
+            # Get the raw socket from the transport
+            raw_sock = self._writer.transport.get_extra_info('socket',
+                                                             default=None)
+            if raw_sock is None:
+                raise RuntimeError("Transport does not expose socket instance")
+
+            # MySQL expects TLS negotiation to happen in the middle of a
+            # TCP connection not at start. Passing in a socket to
+            # open_connection will cause it to negotiate TLS on an existing
+            # connection not initiate a new one.
+            self._reader, self._writer = yield from asyncio.open_connection(
+                sock=raw_sock, ssl=self._ssl_context, loop=self._loop,
+                server_hostname=self._host
+            )
+
         charset_id = charset_by_name(self.charset).id
         if isinstance(self.user, str):
             _user = self.user.encode(self.encoding)
@@ -673,8 +704,16 @@ def _request_authentication(self):
         data = data_init + _user + b'\0'
 
         authresp = b''
-        if self._auth_plugin_name in ('', 'mysql_native_password'):
+
+        auth_plugin = self._client_auth_plugin
+        if not self._client_auth_plugin:
+            # Contains the auth plugin from handshake
+            auth_plugin = self._server_auth_plugin
+
+        if auth_plugin in ('', 'mysql_native_password'):
             authresp = _scramble(self._password.encode('latin1'), self.salt)
+        elif auth_plugin in ('', 'mysql_clear_password'):
+            authresp = self._password.encode('latin1') + b'\0'
 
         if self.server_capabilities & CLIENT.PLUGIN_AUTH_LENENC_CLIENT_DATA:
             data += lenenc_int(len(authresp)) + authresp
@@ -693,11 +732,13 @@ def _request_authentication(self):
             data += db + b'\0'
 
         if self.server_capabilities & CLIENT.PLUGIN_AUTH:
-            name = self._auth_plugin_name
+            name = auth_plugin
             if isinstance(name, str):
                 name = name.encode('ascii')
             data += name + b'\0'
 
+        self._auth_plugin_used = auth_plugin
+
         self.write_packet(data)
         auth_packet = yield from self._read_packet()
 
@@ -710,14 +751,45 @@ def _request_authentication(self):
             plugin_name = auth_packet.read_string()
             if (self.server_capabilities & CLIENT.PLUGIN_AUTH and
                     plugin_name is not None):
-                auth_packet = self._process_auth(plugin_name, auth_packet)
+                auth_packet = yield from self._process_auth(
+                    plugin_name, auth_packet)
             else:
                 # send legacy handshake
                 data = _scramble_323(self._password.encode('latin1'),
                                      self.salt) + b'\0'
                 self.write_packet(data)
                 auth_packet = yield from self._read_packet()
 
+    @asyncio.coroutine
+    def _process_auth(self, plugin_name, auth_packet):
+        if plugin_name == b"mysql_native_password":
+            # https://dev.mysql.com/doc/internals/en/
+            # secure-password-authentication.html#packet-Authentication::
+            # Native41
+            data = _scramble(self._password.encode('latin1'),
+                             auth_packet.read_all())
+        elif plugin_name == b"mysql_old_password":
+            # https://dev.mysql.com/doc/internals/en/
+            # old-password-authentication.html
+            data = _scramble_323(self._password.encode('latin1'),
+                                 auth_packet.read_all()) + b'\0'
+        elif plugin_name == b"mysql_clear_password":
+            # https://dev.mysql.com/doc/internals/en/
+            # clear-text-authentication.html
+            data = self._password.encode('latin1') + b'\0'
+        else:
+            raise OperationalError(
+                2059, "Authentication plugin '%s' not configured" % plugin_name
+            )
+
+        self.write_packet(data)
+        pkt = yield from self._read_packet()
+        pkt.check_error()
+
+        self._auth_plugin_used = plugin_name
+
+        return pkt
+
     # _mysql support
     def thread_id(self):
         return self.server_thread_id[0]
@@ -786,9 +858,9 @@ def _get_server_information(self):
             server_end = data.find(b'\0', i)
             if server_end < 0:  # pragma: no cover - very specific upstream bug
                 # not found \0 and last field so take it all
-                self._auth_plugin_name = data[i:].decode('latin1')
+                self._server_auth_plugin = data[i:].decode('latin1')
             else:
-                self._auth_plugin_name = data[i:server_end].decode('latin1')
+                self._server_auth_plugin = data[i:server_end].decode('latin1')
 
     def get_transaction_status(self):
         return bool(self.server_status & SERVER_STATUS.SERVER_STATUS_IN_TRANS)

tests/test_ssl.py

@@ -0,0 +1,52 @@
+from aiomysql import create_pool
+
+import pytest
+
+
+@pytest.mark.run_loop
+async def test_tls_connect(mysql_server, loop):
+    async with create_pool(**mysql_server['conn_params'],
+                           loop=loop) as pool:
+        async with pool.get() as conn:
+            async with conn.cursor() as cur:
+                # Run simple command
+                await cur.execute("SHOW DATABASES;")
+                value = await cur.fetchall()
+
+                values = [item[0] for item in value]
+                # Spot check the answers, we should at least have mysql
+                # and information_schema
+                assert 'mysql' in values, \
+                    'Could not find the "mysql" table'
+                assert 'information_schema' in values, \
+                    'Could not find the "mysql" table'
+
+                # Check TLS variables
+                await cur.execute("SHOW STATUS LIKE '%Ssl_version%';")
+                value = await cur.fetchone()
+
+                # The context has TLS
+                assert value[1].startswith('TLS'), \
+                    'Not connected to the database with TLS'
+
+
+# MySQL will get you to renegotiate if sent a cleartext password
+@pytest.mark.run_loop
+async def test_auth_plugin_renegotiation(mysql_server, loop):
+    async with create_pool(**mysql_server['conn_params'],
+                           auth_plugin='mysql_clear_password',
+                           loop=loop) as pool:
+        async with pool.get() as conn:
+            async with conn.cursor() as cur:
+                # Run simple command
+                await cur.execute("SHOW DATABASES;")
+                value = await cur.fetchall()
+
+                assert len(value), 'No databases found'
+
+                assert conn._client_auth_plugin == 'mysql_clear_password', \
+                    'Client did not try clear password auth'
+                assert conn._server_auth_plugin == 'mysql_native_password', \
+                    'Server did not ask for native auth'
+                assert conn._auth_plugin_used == b'mysql_native_password', \
+                    'Client did not renegotiate with native auth'