Bug#12897501 REPLICATION DOES NOT SUPPORT WINDOWS AUTH PLUG-IN

Connection of slave to master using a replication account which authenticates
with an external plugin was not possible.

Fixed by making sure that the CLIENT_PLUGIN_AUTH capability is set when client connects using mysql_real_connect(). Also, a plugin-dir path used by client library to locate authentication plugins is set based on the analogous server setting. This is done in connect_to_master() function before a call to mysql_real_connect().

libmysql/client_settings.h

@@ -22,6 +22,11 @@
 extern uint		mysql_port;
 extern char *	mysql_unix_port;
 
+/*
+ Note: CLIENT_CAPABILITIES is also defined in sql/client_settings.h.
+ When adding capabilities here, consider if they should be also added to
+ the server's version.
+*/
 #define CLIENT_CAPABILITIES (CLIENT_LONG_PASSWORD | \
                              CLIENT_LONG_FLAG |     \
                              CLIENT_TRANSACTIONS |  \

mysql-test/r/auth_rpl.result

@@ -0,0 +1,22 @@
+include/master-slave.inc
+[connection master]
+[connection slave]
+include/stop_slave.inc
+[connection master]
+CREATE USER 'plug_user' IDENTIFIED WITH 'test_plugin_server' AS 'plug_user';
+GRANT REPLICATION SLAVE ON *.* TO plug_user;
+FLUSH PRIVILEGES;
+[connection slave]
+CHANGE MASTER TO MASTER_USER= 'plug_user';
+include/start_slave.inc
+# Slave in-sync with master now.
+SELECT user, plugin, authentication_string FROM mysql.user WHERE user LIKE 'plug_user';
+user	plugin	authentication_string
+plug_user	test_plugin_server	plug_user
+# Cleanup (on slave).
+include/stop_slave.inc
+CHANGE MASTER TO MASTER_USER='root';
+DROP USER 'plug_user';
+# Cleanup (on master).
+DROP USER 'plug_user';
+include/rpl_end.inc

mysql-test/t/auth_rpl-master.opt

@@ -0,0 +1,2 @@
+$PLUGIN_AUTH_OPT
+$PLUGIN_AUTH_LOAD

mysql-test/t/auth_rpl-slave.opt

@@ -0,0 +1,4 @@
+--master-retry-count=1
+$PLUGIN_AUTH_OPT
+$PLUGIN_AUTH_LOAD
+

mysql-test/t/auth_rpl.test

@@ -0,0 +1,64 @@
+--source include/have_plugin_auth.inc
+--source include/not_embedded.inc
+--source include/master-slave.inc
+
+#
+# Check that replication slave can connect to master using an account
+# which authenticates with an external authentication plugin (bug#12897501).
+
+#
+# First stop the slave to guarantee that nothing is replicated.
+#
+--connection slave
+--echo [connection slave]
+--source include/stop_slave.inc
+#
+# Create an replication account on the master.
+#
+--connection master
+--echo [connection master]
+CREATE USER 'plug_user' IDENTIFIED WITH 'test_plugin_server' AS 'plug_user';
+GRANT REPLICATION SLAVE ON *.* TO plug_user;
+FLUSH PRIVILEGES;
+
+#
+# Now go to slave and change the replication user.
+#
+--connection slave
+--echo [connection slave]
+--let $master_user= query_get_value(SHOW SLAVE STATUS, Master_User, 1)
+CHANGE MASTER TO MASTER_USER= 'plug_user';
+
+#
+# Start slave with new replication account - this should trigger connection
+# to the master server.
+#
+--source include/start_slave.inc
+
+# Replicate all statements executed on master, in this case,
+# (creation of the plug_user account).
+#
+--connection master
+--sync_slave_with_master
+--echo # Slave in-sync with master now.
+
+SELECT user, plugin, authentication_string FROM mysql.user WHERE user LIKE 'plug_user';
+
+#
+# Now we can stop the slave and clean up.
+#
+# Note: it is important that slave is stopped at this
+# moment - otherwise master's cleanup statements
+# would be replicated on slave!
+#
+--echo # Cleanup (on slave).
+--source include/stop_slave.inc
+eval CHANGE MASTER TO MASTER_USER='$master_user';
+DROP USER 'plug_user';
+
+--echo # Cleanup (on master).
+--connection master
+DROP USER 'plug_user';
+
+--let $rpl_only_running_threads= 1
+--source include/rpl_end.inc

sql/client_settings.h

@@ -23,9 +23,18 @@
 #include <thr_alarm.h>
 #include <sql_common.h>
 
-#define CLIENT_CAPABILITIES (CLIENT_LONG_PASSWORD | CLIENT_LONG_FLAG |	  \
-                             CLIENT_SECURE_CONNECTION | CLIENT_TRANSACTIONS | \
-			     CLIENT_PROTOCOL_41 | CLIENT_SECURE_CONNECTION)
+/*
+ Note: CLIENT_CAPABILITIES is also defined in libmysql/client_settings.h.
+ When adding capabilities here, consider if they should be also added to
+ the libmysql version.
+*/
+#define CLIENT_CAPABILITIES (CLIENT_LONG_PASSWORD | \
+                             CLIENT_LONG_FLAG |     \
+                             CLIENT_SECURE_CONNECTION | \
+                             CLIENT_TRANSACTIONS |  \
+                             CLIENT_PROTOCOL_41 |   \
+                             CLIENT_SECURE_CONNECTION | \
+                             CLIENT_PLUGIN_AUTH)
 
 #define read_user_name(A) {}
 #undef HAVE_SMEM

sql/slave.cc

@@ -4204,6 +4204,10 @@ static int connect_to_master(THD* thd, MYSQL* mysql, Master_info* mi,
   /* This one is not strictly needed but we have it here for completeness */
   mysql_options(mysql, MYSQL_SET_CHARSET_DIR, (char *) charsets_dir);
 
+  /* Set MYSQL_PLUGIN_DIR in case master asks for an external authentication plugin */
+  if (opt_plugin_dir_ptr && *opt_plugin_dir_ptr)
+    mysql_options(mysql, MYSQL_PLUGIN_DIR, opt_plugin_dir_ptr);
+
   while (!(slave_was_killed = io_slave_killed(thd,mi)) &&
          (reconnect ? mysql_reconnect(mysql) != 0 :
           mysql_real_connect(mysql, mi->host, mi->user, mi->password, 0,