bugfix: failed to build on the old nginx version.

Author: zhuizhuhaomeng

src/ngx_http_lua_module.c

@@ -1514,7 +1514,11 @@ ngx_http_lua_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
     ngx_conf_merge_bitmask_value(conf->ssl_protocols, prev->ssl_protocols,
                                  (NGX_CONF_BITMASK_SET
                                   |NGX_SSL_TLSv1|NGX_SSL_TLSv1_1
-                                  |NGX_SSL_TLSv1_2|NGX_SSL_TLSv1_3));
+                                  |NGX_SSL_TLSv1_2
+#ifdef NGX_SSL_TLSv1_3
+                                  |NGX_SSL_TLSv1_3
+#endif
+                                  ));
 
     ngx_conf_merge_str_value(conf->ssl_ciphers, prev->ssl_ciphers,
                              "DEFAULT");

src/ngx_http_lua_ssl_client_helloby.c

@@ -712,7 +712,7 @@ ngx_http_lua_ffi_ssl_set_protocols(ngx_http_request_t *r,
     }
 #endif
 
-#ifdef SSL_OP_NO_TLSv1_3
+#if defined(NGX_SSL_TLSv1_3) && defined( SSL_OP_NO_TLSv1_3)
     SSL_clear_options(ssl_conn, SSL_OP_NO_TLSv1_3);
     if (!(protocols & NGX_SSL_TLSv1_3)) {
         SSL_set_options(ssl_conn, SSL_OP_NO_TLSv1_3);