client-connect: Implement deferred connect support for plugin API v2

The V2 API is simpler than the V1 API since there is no passing of
data via files. This also means that with the current API the V2 API
cannot support async notify via files. Adding a file just for async
notify seems very hacky and when needed we should implement a better
option when async is needed for the plugin V2 API.

Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20200719173436.16431-5-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg20480.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

diff --git a/include/openvpn-plugin.h.in b/include/openvpn-plugin.h.in
index 99aa1678594d6bfe54a85010d4c9c4170db62123..38fbe0976abbebac6139280c2e75befa7fca03e7 100644 (file)
--- a/include/openvpn-plugin.h.in
+++ b/include/openvpn-plugin.h.in
@@ -130,7 +130,8 @@ extern "C" {
 #define OPENVPN_PLUGIN_ENABLE_PF                11
 #define OPENVPN_PLUGIN_ROUTE_PREDOWN            12
 #define OPENVPN_PLUGIN_CLIENT_CONNECT_DEFER     13
-#define OPENVPN_PLUGIN_N                        14
+#define OPENVPN_PLUGIN_CLIENT_CONNECT_DEFER_V2  14
+#define OPENVPN_PLUGIN_N                        15
 
 /*
  * Build a mask out of a set of plug-in types.

diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 622eb2eeb19905be92f745f4d0cd9a09da071daa..2ae9c03e8b7bc3409b330a0b4e6541d747581076 100644 (file)
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -2111,36 +2111,48 @@ multi_client_connect_call_plugin_v2(struct multi_context *m,
                                     bool deferred,
                                     unsigned int *option_types_found)
 {
-    if (deferred)
-    {
-        return CC_RET_FAILED;
-    }
     enum client_connect_return ret = CC_RET_SKIPPED;
 #ifdef ENABLE_PLUGIN
     ASSERT(m);
     ASSERT(mi);
     ASSERT(option_types_found);
 
+    int call = deferred ? OPENVPN_PLUGIN_CLIENT_CONNECT_DEFER_V2 :
+               OPENVPN_PLUGIN_CLIENT_CONNECT_V2;
     /* V2 callback, use a plugin_return struct for passing back return info */
-    if (plugin_defined(mi->context.plugins, OPENVPN_PLUGIN_CLIENT_CONNECT_V2))
+    if (plugin_defined(mi->context.plugins, call))
     {
         struct plugin_return pr;
 
         plugin_return_init(&pr);
 
-        if (plugin_call(mi->context.plugins, OPENVPN_PLUGIN_CLIENT_CONNECT_V2,
-                        NULL, &pr, mi->context.c2.es)
-            != OPENVPN_PLUGIN_FUNC_SUCCESS)
+        int plug_ret = plugin_call(mi->context.plugins, call,
+                                   NULL, &pr, mi->context.c2.es);
+        if (plug_ret == OPENVPN_PLUGIN_FUNC_SUCCESS)
         {
-            msg(M_WARN, "WARNING: client-connect-v2 plugin call failed");
-            ret = CC_RET_FAILED;
+            multi_client_connect_post_plugin(m, mi, &pr, option_types_found);
+            ret = CC_RET_SUCCEEDED;
+        }
+        else if (plug_ret == OPENVPN_PLUGIN_FUNC_DEFERRED)
+        {
+            ret = CC_RET_DEFERRED;
+            if (!(plugin_defined(mi->context.plugins,
+                                 OPENVPN_PLUGIN_CLIENT_CONNECT_DEFER_V2)))
+            {
+                msg(M_WARN, "A plugin that defers from the "
+                    "OPENVPN_PLUGIN_CLIENT_CONNECT_V2 call must also "
+                    "declare support for "
+                    "OPENVPN_PLUGIN_CLIENT_CONNECT_DEFER_V2");
+                ret = CC_RET_FAILED;
+            }
         }
         else
         {
-            multi_client_connect_post_plugin(m, mi, &pr, option_types_found);
-            ret = CC_RET_SUCCEEDED;
+            msg(M_WARN, "WARNING: client-connect-v2 plugin call failed");
+            ret = CC_RET_FAILED;
         }
 
+
         plugin_return_free(&pr);
     }
 #endif /* ifdef ENABLE_PLUGIN */

diff --git a/src/openvpn/plugin.c b/src/openvpn/plugin.c
index 9a6fa3cb866f3177f4cc7245d8803e05f168dd83..8b351c45abdbd5d72f3cb6efb46a09661de45037 100644 (file)
--- a/src/openvpn/plugin.c
+++ b/src/openvpn/plugin.c
@@ -107,6 +107,9 @@ plugin_type_name(const int type)
         case OPENVPN_PLUGIN_CLIENT_CONNECT_DEFER:
             return "PLUGIN_CLIENT_CONNECT_DEFER";
 
+        case OPENVPN_PLUGIN_CLIENT_CONNECT_DEFER_V2:
+            return "PLUGIN_CLIENT_CONNECT_DEFER_V2";
+
         case OPENVPN_PLUGIN_CLIENT_DISCONNECT:
             return "PLUGIN_CLIENT_DISCONNECT";