adds tls sni support to mysql2

Author: mikemackintosh

ext/mysql2/client.c

@@ -504,26 +504,34 @@ static int opt_connect_attr_add_i(VALUE key, VALUE value, VALUE arg)
 }
 #endif
 
-static VALUE rb_mysql_connect(VALUE self, VALUE user, VALUE pass, VALUE host, VALUE port, VALUE database, VALUE socket, VALUE flags, VALUE conn_attrs) {
+static VALUE rb_mysql_connect(VALUE self, VALUE user, VALUE pass, VALUE host, VALUE port, VALUE database, VALUE socket, VALUE flags, VALUE conn_attrs, VALUE tls_sni_name) {
   struct nogvl_connect_args args;
   time_t start_time, end_time, elapsed_time, connect_timeout;
+  const char *sni_hostname;
   VALUE rv;
   GET_CLIENT(self);
 
-  args.host        = NIL_P(host)     ? NULL : StringValueCStr(host);
-  args.unix_socket = NIL_P(socket)   ? NULL : StringValueCStr(socket);
-  args.port        = NIL_P(port)     ? 0    : NUM2INT(port);
-  args.user        = NIL_P(user)     ? NULL : StringValueCStr(user);
-  args.passwd      = NIL_P(pass)     ? NULL : StringValueCStr(pass);
-  args.db          = NIL_P(database) ? NULL : StringValueCStr(database);
-  args.mysql       = wrapper->client;
-  args.client_flag = NUM2ULONG(flags);
+  args.host         = NIL_P(host)     ? NULL : StringValueCStr(host);
+  args.unix_socket  = NIL_P(socket)   ? NULL : StringValueCStr(socket);
+  args.port         = NIL_P(port)     ? 0    : NUM2INT(port);
+  args.user         = NIL_P(user)     ? NULL : StringValueCStr(user);
+  args.passwd       = NIL_P(pass)     ? NULL : StringValueCStr(pass);
+  args.db           = NIL_P(database) ? NULL : StringValueCStr(database);
+  args.mysql        = wrapper->client;
+  args.client_flag   = NUM2ULONG(flags);
+
+  sni_hostname      = NIL_P(tls_sni_name) ? NULL : StringValueCStr(tls_sni_name);
 
 #ifdef CLIENT_CONNECT_ATTRS
   mysql_options(wrapper->client, MYSQL_OPT_CONNECT_ATTR_RESET, 0);
   rb_hash_foreach(conn_attrs, opt_connect_attr_add_i, (VALUE)wrapper);
 #endif
 
+  if(sni_hostname != NULL) {
+    /* Set the TLS SNI name if provided */
+    mysql_options(wrapper->client, MYSQL_OPT_TLS_SNI_SERVERNAME, sni_hostname);
+  }
+
   if (wrapper->connect_timeout)
     time(&start_time);
   rv = (VALUE) rb_thread_call_without_gvl(nogvl_connect, &args, RUBY_UBF_IO, 0);
@@ -1619,7 +1627,7 @@ void init_mysql2_client() {
   rb_define_private_method(cMysql2Client, "ssl_mode=", rb_set_ssl_mode_option, 1);
   rb_define_private_method(cMysql2Client, "enable_cleartext_plugin=", set_enable_cleartext_plugin, 1);
   rb_define_private_method(cMysql2Client, "initialize_ext", initialize_ext, 0);
-  rb_define_private_method(cMysql2Client, "connect", rb_mysql_connect, 8);
+  rb_define_private_method(cMysql2Client, "connect", rb_mysql_connect, 9);
   rb_define_private_method(cMysql2Client, "_query", rb_mysql_query, 2);
 
   sym_id              = ID2SYM(rb_intern("id"));

lib/mysql2/client.rb

@@ -73,23 +73,25 @@ def initialize(opts = {})
 
       check_and_clean_query_options
 
-      user     = opts[:username] || opts[:user]
-      pass     = opts[:password] || opts[:pass]
-      host     = opts[:host] || opts[:hostname]
-      port     = opts[:port]
-      database = opts[:database] || opts[:dbname] || opts[:db]
-      socket   = opts[:socket] || opts[:sock]
+      user         = opts[:username] || opts[:user]
+      pass         = opts[:password] || opts[:pass]
+      host         = opts[:host] || opts[:hostname]
+      tls_sni_name = opts[:tls_sni_name]
+      port         = opts[:port]
+      database     = opts[:database] || opts[:dbname] || opts[:db]
+      socket       = opts[:socket] || opts[:sock]
 
       # Correct the data types before passing these values down to the C level
       user = user.to_s unless user.nil?
       pass = pass.to_s unless pass.nil?
       host = host.to_s unless host.nil?
       port = port.to_i unless port.nil?
       database = database.to_s unless database.nil?
+      tls_sni_name = tls_sni_name.to_s unless tls_sni_name.nil?
       socket = socket.to_s unless socket.nil?
       conn_attrs = parse_connect_attrs(opts[:connect_attrs])
 
-      connect user, pass, host, port, database, socket, flags, conn_attrs
+      connect user, pass, host, port, database, socket, flags, conn_attrs, tls_sni_name
     end
 
     def parse_ssl_mode(mode)