MXS-1032: Add configurable connector plugin directory

The connector plugin directory can now be controlled with the
`connector_plugindir` argument and configuration option. This should allow
the connector to use the system plugins if the versions are binary
compatible.

Replaced calls to mysql_options to mysql_optionsv as the former is
deprecated in Connector-C 3.0 and the latter is supported in Connector-C
2.3.

Documentation/Getting-Started/Configuration-Guide.md

@@ -442,6 +442,17 @@ files.
 execdir=/usr/local/bin/
 ```
 
+#### `connector_plugindir`
+
+Location of the MariaDB Connector-C plugin directory. The MariaDB Connector-C
+used in MaxScale can use this directory to load authentication plugins. The
+versions of the plugins must be binary compatible with the connector version
+that MaxScale was built with.
+
+```
+connector_plugindir=/usr/lib/plugin/
+```
+
 #### `persistdir`
 
 Configure the directory where persisted configurations are stored. When a new

cmake/install_layout.cmake

@@ -22,6 +22,7 @@ set(DEFAULT_EXEC_SUBPATH "${MAXSCALE_BINDIR}" CACHE PATH "Default executable sub
 set(DEFAULT_CONFIG_SUBPATH "etc" CACHE PATH "Default configuration subpath")
 set(DEFAULT_CONFIG_PERSIST_SUBPATH "maxscale.cnf.d" CACHE PATH "Default persisted configuration subpath")
 set(DEFAULT_MODULE_CONFIG_SUBPATH "${DEFAULT_CONFIG_SUBPATH}/maxscale.modules.d" CACHE PATH "Default configuration subpath")
+set(DEFAULT_CONNECTOR_PLUGIN_SUBPATH "lib/plugin" CACHE PATH "Default connector plugin subpath")
 
 set(DEFAULT_PIDDIR ${MAXSCALE_VARDIR}/${DEFAULT_PID_SUBPATH} CACHE PATH "Default PID file directory")
 set(DEFAULT_LOGDIR ${MAXSCALE_VARDIR}/${DEFAULT_LOG_SUBPATH} CACHE PATH "Default log directory")
@@ -33,6 +34,7 @@ set(DEFAULT_EXECDIR ${CMAKE_INSTALL_PREFIX}/${DEFAULT_EXEC_SUBPATH} CACHE PATH "
 set(DEFAULT_CONFIGDIR /${DEFAULT_CONFIG_SUBPATH} CACHE PATH "Default configuration directory")
 set(DEFAULT_CONFIG_PERSISTDIR ${DEFAULT_DATADIR}/${DEFAULT_CONFIG_PERSIST_SUBPATH} CACHE PATH "Default persisted configuration directory")
 set(DEFAULT_MODULE_CONFIGDIR /${DEFAULT_MODULE_CONFIG_SUBPATH} CACHE PATH "Default module configuration directory")
+set(DEFAULT_CONNECTOR_PLUGINDIR ${MAXSCALE_VARDIR}/${DEFAULT_CONNECTOR_PLUGIN_SUBPATH} CACHE PATH "Default connector plugin directory")
 
 # Massage TARGET_COMPONENT into a list
 if (TARGET_COMPONENT)

include/maxscale/paths.h.in

@@ -31,6 +31,7 @@ MXS_BEGIN_DECLS
 #define MXS_DEFAULT_CONFIG_SUBPATH "@DEFAULT_CONFIG_SUBPATH@"
 #define MXS_DEFAULT_CONFIG_PERSIST_SUBPATH "@DEFAULT_CONFIG_PERSIST_SUBPATH@"
 #define MXS_DEFAULT_MODULE_CONFIG_SUBPATH "@DEFAULT_MODULE_CONFIG_SUBPATH@"
+#define MXS_DEFAULT_CONNECTOR_PLUGIN_SUBPATH "@DEFAULT_CONNECTOR_PLUGIN_SUBPATH@"
 
 /** Default file locations, configured by CMake */
 #define MXS_DEFAULT_CONFIGDIR         "@DEFAULT_CONFIGDIR@"
@@ -43,6 +44,7 @@ MXS_BEGIN_DECLS
 #define MXS_DEFAULT_EXECDIR           "@DEFAULT_EXECDIR@"
 #define MXS_DEFAULT_CONFIG_PERSISTDIR "@DEFAULT_CONFIG_PERSISTDIR@"
 #define MXS_DEFAULT_MODULE_CONFIGDIR  "@DEFAULT_MODULE_CONFIGDIR@"
+#define MXS_DEFAULT_CONNECTOR_PLUGINDIR "@DEFAULT_CONNECTOR_PLUGINDIR@"
 
 static const char* default_cnf_fname = "maxscale.cnf";
 static const char* default_configdir = MXS_DEFAULT_CONFIGDIR;
@@ -59,6 +61,7 @@ static const char* default_langdir  = MXS_DEFAULT_LANGDIR;
 static const char* default_execdir  = MXS_DEFAULT_EXECDIR;
 static const char* default_config_persistdir = MXS_DEFAULT_CONFIG_PERSISTDIR;
 static const char* default_module_configdir = MXS_DEFAULT_MODULE_CONFIGDIR;
+static const char* default_connector_plugindir  = MXS_DEFAULT_CONNECTOR_PLUGINDIR;
 
 static char* configdir = NULL; /*< Where the config file is found e.g. /etc/ */
 static char* config_persistdir = NULL;/*< Persisted configs e.g. /var/lib/maxscale/maxscale.cnf.d/ */
@@ -71,6 +74,7 @@ static char* processdatadir = NULL; /*< Process specific data directory */
 static char* langdir = NULL;
 static char* piddir = NULL;
 static char* execdir = NULL;
+static char* connector_plugindir = NULL;
 
 void set_libdir(char* param);
 void set_datadir(char* param);
@@ -83,6 +87,7 @@ void set_logdir(char* param);
 void set_langdir(char* param);
 void set_piddir(char* param);
 void set_execdir(char* param);
+void set_connector_plugindir(char* param);
 char* get_libdir();
 char* get_datadir();
 char* get_process_datadir();
@@ -94,5 +99,6 @@ char* get_piddir();
 char* get_logdir();
 char* get_langdir();
 char* get_execdir();
+char* get_connector_plugindir();
 
 MXS_END_DECLS

server/core/gateway.cc

@@ -138,6 +138,7 @@ static struct option long_options[] =
     {"version",          no_argument,       0, 'v'},
     {"version-full",     no_argument,       0, 'V'},
     {"help",             no_argument,       0, '?'},
+    {"connector_plugindir", required_argument, 0, 'H'},
     {0, 0, 0, 0}
 };
 static bool syslog_configured = false;
@@ -927,6 +928,8 @@ static void usage(void)
             "  -E, --execdir=PATH          path to the maxscale and other executable files\n"
             "  -F, --persistdir=PATH       path to persisted configuration directory\n"
             "  -M, --module_configdir=PATH path to module configuration directory\n"
+            "  -H, --connector_plugindir=PATH\n"
+            "                              path to MariaDB Connector-C plugin directory\n"
             "  -N, --language=PATH         path to errmsg.sys file\n"
             "  -P, --piddir=PATH           path to PID file directory\n"
             "  -R, --basedir=PATH          base path for all other paths\n"
@@ -1332,7 +1335,7 @@ int main(int argc, char **argv)
         }
     }
 
-    while ((opt = getopt_long(argc, argv, "dcf:l:vVs:S:?L:D:C:B:U:A:P:G:N:E:F:M:",
+    while ((opt = getopt_long(argc, argv, "dcf:l:vVs:S:?L:D:C:B:U:A:P:G:N:E:F:M:H:",
                               long_options, &option_index)) != -1)
     {
         bool succp = true;
@@ -1496,6 +1499,16 @@ int main(int argc, char **argv)
                 succp = false;
             }
             break;
+        case 'H':
+            if (handle_path_arg(&tmp_path, optarg, NULL, true, false))
+            {
+                set_connector_plugindir(tmp_path);
+            }
+            else
+            {
+                succp = false;
+            }
+            break;
         case 'F':
             if (handle_path_arg(&tmp_path, optarg, NULL, true, true))
             {
@@ -2532,6 +2545,20 @@ static int cnf_preparser(void* data, const char* section, const char* name, cons
                 }
             }
         }
+        else if (strcmp(name, "connector_plugindir") == 0)
+        {
+            if (strcmp(get_connector_plugindir(), default_connector_plugindir) == 0)
+            {
+                if (handle_path_arg((char**)&tmp, (char*)value, NULL, true, false))
+                {
+                    set_connector_plugindir(tmp);
+                }
+                else
+                {
+                    return 0;
+                }
+            }
+        }
         else if (strcmp(name, "persistdir") == 0)
         {
             if (strcmp(get_config_persistdir(), default_config_persistdir) == 0)

server/core/monitor.c

@@ -1181,10 +1181,10 @@ mon_connect_to_db(MXS_MONITOR* mon, MXS_MONITOR_SERVERS *database)
 
         char *dpwd = decrypt_password(passwd);
 
-        mysql_options(database->con, MYSQL_OPT_CONNECT_TIMEOUT, (void *) &mon->connect_timeout);
+        mysql_optionsv(database->con, MYSQL_OPT_CONNECT_TIMEOUT, (void *) &mon->connect_timeout);
-        mysql_options(database->con, MYSQL_OPT_READ_TIMEOUT, (void *) &mon->read_timeout);
+        mysql_optionsv(database->con, MYSQL_OPT_READ_TIMEOUT, (void *) &mon->read_timeout);
-        mysql_options(database->con, MYSQL_OPT_WRITE_TIMEOUT, (void *) &mon->write_timeout);
+        mysql_optionsv(database->con, MYSQL_OPT_WRITE_TIMEOUT, (void *) &mon->write_timeout);
-
+        mysql_optionsv(database->con, MYSQL_PLUGIN_DIR, get_connector_plugindir());
         time_t start = time(NULL);
         bool result = (mxs_mysql_real_connect(database->con, database->server, uname, dpwd) != NULL);
         time_t end = time(NULL);

server/core/paths.c

@@ -137,6 +137,17 @@ void set_execdir(char* param)
     execdir = param;
 }
 
+/**
+ * Set the connector plugin directory.
+ * @param str Path to directory
+ */
+void set_connector_plugindir(char* param)
+{
+    MXS_FREE(connector_plugindir);
+    clean_up_pathname(param);
+    connector_plugindir = param;
+}
+
 /**
  * Get the directory with all the modules.
  * @return The module directory
@@ -235,3 +246,12 @@ char* get_execdir()
 {
     return execdir ? execdir : (char*) default_execdir;
 }
+
+/**
+ * Get connector plugin directory
+ * @return The connector plugin directory
+ */
+char* get_connector_plugindir()
+{
+    return connector_plugindir ? connector_plugindir : (char*) default_connector_plugindir;
+}

server/modules/authenticator/MySQLAuth/dbusers.c

@@ -31,6 +31,7 @@
 #include <mysqld_error.h>
 #include <maxscale/mysql_utils.h>
 #include <maxscale/alloc.h>
+#include <maxscale/paths.h>
 
 /** Don't include the root user */
 #define USERS_QUERY_NO_ROOT " AND user.user NOT IN ('root')"
@@ -408,22 +409,7 @@ MYSQL *gw_mysql_init()
 
     if (con)
     {
-        if (gw_mysql_set_timeouts(con) == 0)
+        if (gw_mysql_set_timeouts(con) != 0)
-        {
-            // MYSQL_OPT_USE_REMOTE_CONNECTION must be set if the embedded
-            // libary is used. With Connector-C (at least 2.2.1) the call
-            // fails.
-#if !defined(LIBMARIADB)
-            if (mysql_options(con, MYSQL_OPT_USE_REMOTE_CONNECTION, NULL) != 0)
-            {
-                MXS_ERROR("Failed to set external connection. "
-                          "It is needed for backend server connections.");
-                mysql_close(con);
-                con = NULL;
-            }
-#endif
-        }
-        else
         {
             MXS_ERROR("Failed to set timeout values for backend connection.");
             mysql_close(con);
@@ -454,21 +440,21 @@ static int gw_mysql_set_timeouts(MYSQL* handle)
 
     MXS_CONFIG* cnf = config_get_global_options();
 
-    if ((rc = mysql_options(handle, MYSQL_OPT_READ_TIMEOUT,
+    if ((rc = mysql_optionsv(handle, MYSQL_OPT_READ_TIMEOUT,
                             (void *) &cnf->auth_read_timeout)))
     {
         MXS_ERROR("Failed to set read timeout for backend connection.");
         goto retblock;
     }
 
-    if ((rc = mysql_options(handle, MYSQL_OPT_CONNECT_TIMEOUT,
+    if ((rc = mysql_optionsv(handle, MYSQL_OPT_CONNECT_TIMEOUT,
                             (void *) &cnf->auth_conn_timeout)))
     {
         MXS_ERROR("Failed to set connect timeout for backend connection.");
         goto retblock;
     }
 
-    if ((rc = mysql_options(handle, MYSQL_OPT_WRITE_TIMEOUT,
+    if ((rc = mysql_optionsv(handle, MYSQL_OPT_WRITE_TIMEOUT,
                             (void *) &cnf->auth_write_timeout)))
     {
         MXS_ERROR("Failed to set write timeout for backend connection.");
@@ -499,9 +485,10 @@ static bool check_server_permissions(SERVICE *service, SERVER* server,
     }
 
     MXS_CONFIG* cnf = config_get_global_options();
-    mysql_options(mysql, MYSQL_OPT_READ_TIMEOUT, &cnf->auth_read_timeout);
+    mysql_optionsv(mysql, MYSQL_OPT_READ_TIMEOUT, &cnf->auth_read_timeout);
-    mysql_options(mysql, MYSQL_OPT_CONNECT_TIMEOUT, &cnf->auth_conn_timeout);
+    mysql_optionsv(mysql, MYSQL_OPT_CONNECT_TIMEOUT, &cnf->auth_conn_timeout);
-    mysql_options(mysql, MYSQL_OPT_WRITE_TIMEOUT, &cnf->auth_write_timeout);
+    mysql_optionsv(mysql, MYSQL_OPT_WRITE_TIMEOUT, &cnf->auth_write_timeout);
+    mysql_optionsv(mysql, MYSQL_PLUGIN_DIR, get_connector_plugindir());
 
     if (mxs_mysql_real_connect(mysql, server, user, password) == NULL)
     {