Add support for marking connections as persistent

Persistent connections have openvpn.exe daemon started external to the GUI (e.g., by the automatic service). This patch adds support for attaching to the management i/f of such daemons from the GUI and control the connection. The GUI never stops or starts the openvpn.exe process in this case. Instead, connect and disconnect buttons signal the management interface of a running openvpn.exe process to start the tunnel by attaching to mgmt i/f and sending hold-release if needed or stop it and wait in management-hold state (see DisconnectDaemon()). When the GUI process exits, persistent connections are left in their current state using DetachOpenVPN(). No connections are marked as persistent as yet. That is done in a following commit. Signed-off-by: Selva Nair <[email protected]>
OpenVPN · Aug 8, 2022 · 428ee29 · 428ee29
1 parent f8a1495
commit 428ee29
Show file tree

Hide file tree

Showing 29 changed files with 224 additions and 12 deletions.
diff --git a/main.c b/main.c
@@ -351,10 +351,23 @@ StopAllOpenVPN()
 {
     int i;
 
+    /* Stop all connections started by us -- we leave persistent ones
+     * at their current state. Use the disconnect menu to put them into
+     * hold state before exit, if desired.
+     */
     for (i = 0; i < o.num_configs; i++)
     {
         if (o.conn[i].state != disconnected)
-            StopOpenVPN(&o.conn[i]);
+        {
+            if (o.conn[i].flags & FLAG_DAEMON_PERSISTENT)
+            {
+                DetachOpenVPN(&o.conn[i]);
+            }
+            else
+            {
+                StopOpenVPN(&o.conn[i]);
+            }
+        }
     }
 
     /* Wait for all connections to terminate (Max 5 sec) */
@@ -756,14 +769,21 @@ CloseApplication(HWND hwnd)
     && ShowLocalizedMsgEx(MB_YESNO, NULL, _T("Exit OpenVPN"), IDS_NFO_SERVICE_ACTIVE_EXIT) == IDNO)
             return;
 
+    /* Show a message if any non-persistent connections are active */
     for (i = 0; i < o.num_configs; i++)
     {
-        if (o.conn[i].state == disconnected)
+        if (o.conn[i].state == disconnected
+            || o.conn[i].flags & FLAG_DAEMON_PERSISTENT)
+        {
             continue;
+        }
 
         /* Ask for confirmation if still connected */
         if (ShowLocalizedMsgEx(MB_YESNO, NULL, _T("Exit OpenVPN"), IDS_NFO_ACTIVE_CONN_EXIT) == IDNO)
+        {
             return;
+        }
+        break; /* show the above message box only once */
     }
 
     DestroyWindow(hwnd);

diff --git a/main.h b/main.h
@@ -58,10 +58,12 @@
 #define WM_OVPN_NOTIFY         (WM_APP + 16)
 #define WM_OVPN_EXIT           (WM_APP + 17)
 #define WM_OVPN_SILENT         (WM_APP + 18)
+#define WM_OVPN_RELEASE        (WM_APP + 19)
 #define WM_OVPN_IMPORT         (WM_APP + 20)
 #define WM_OVPN_RESCAN         (WM_APP + 21)
 #define WM_OVPN_ECHOMSG        (WM_APP + 22)
 #define WM_OVPN_STATE          (WM_APP + 23)
+#define WM_OVPN_DETACH         (WM_APP + 24)
 
 /* bool definitions */
 #define bool int

diff --git a/manage.c b/manage.c
@@ -204,8 +204,12 @@ OnManagement(SOCKET sk, LPARAM lParam)
     case FD_CONNECT:
         if (WSAGETSELECTERROR(lParam))
         {
-            if (time(NULL) < c->manage.timeout)
+            /* keep trying for connections with persistent daemons */
+            if (c->flags & FLAG_DAEMON_PERSISTENT
+                || time(NULL) < c->manage.timeout)
+            {
                 connect(c->manage.sk, (SOCKADDR *)&c->manage.skaddr, sizeof(c->manage.skaddr));
+            }
             else
             {
                 /* Connection to MI timed out. */

diff --git a/openvpn-gui-res.h b/openvpn-gui-res.h
@@ -248,6 +248,7 @@
 #define IDS_NFO_CONFIG_AUTH_PENDING     1256
 #define IDS_ERR_ADD_USER_TO_ADMIN_GROUP 1257
 #define IDS_NFO_BYTECOUNT               1258
+#define IDS_NFO_STATE_ONHOLD            1259
 
 /* Program Startup Related */
 #define IDS_ERR_OPEN_DEBUG_FILE         1301

diff --git a/openvpn.c b/openvpn.c
@@ -121,6 +121,9 @@ OnReady(connection_t *c, UNUSED char *msg)
     ManagementCommand(c, "log on all", OnLogLine, combined);
     ManagementCommand(c, "echo on all", OnEcho, combined);
     ManagementCommand(c, "bytecount 5", NULL, regular);
+
+    /* ask for the current state, especially useful when the daemon was prestarted */
+    ManagementCommand(c, "state", OnStateChange, regular);
 }
 
 
@@ -130,6 +133,19 @@ OnReady(connection_t *c, UNUSED char *msg)
 void
 OnHold(connection_t *c, UNUSED char *msg)
 {
+    EnableWindow(GetDlgItem(c->hwndStatus, ID_RESTART), TRUE);
+    if ((c->flags & FLAG_DAEMON_PERSISTENT) && (c->state == disconnecting))
+    {
+        /* retain the hold state if we are here while disconnecting  */
+        c->state = onhold;
+        SetMenuStatus(c, onhold);
+        SetDlgItemText(c->hwndStatus, ID_TXT_STATUS, LoadLocalizedString(IDS_NFO_STATE_ONHOLD));
+        SetStatusWinIcon(c->hwndStatus, ID_ICO_DISCONNECTED);
+        EnableWindow(GetDlgItem(c->hwndStatus, ID_DISCONNECT), FALSE);
+        CheckAndSetTrayIcon();
+        return;
+    }
+    EnableWindow(GetDlgItem(c->hwndStatus, ID_DISCONNECT), TRUE);
     ManagementCommand(c, "hold off", NULL, regular);
     ManagementCommand(c, "hold release", NULL, regular);
 }
@@ -296,8 +312,11 @@ OnStateChange(connection_t *c, char *data)
         LoadLocalizedStringBuf(ip_txt, _countof(ip_txt), IDS_NFO_ASSIGN_IP, ip);
 
         /* Run Connect Script */
-        if (c->state == connecting || c->state == resuming)
+        if (!(c->flags & FLAG_DAEMON_PERSISTENT)
+            && (c->state == connecting || c->state == resuming))
+        {
             RunConnectScript(c, false);
+        }
 
         /* Show connection tray balloon */
         if ((c->state == connecting   && o.show_balloon != 0)
@@ -1319,6 +1338,7 @@ OnStop(connection_t *c, UNUSED char *msg)
         c->failed_auth_attempts = 0;
         c->state = disconnected;
         CheckAndSetTrayIcon();
+        SetDlgItemText(c->hwndStatus, ID_TXT_STATUS, LoadLocalizedString(IDS_NFO_STATE_DISCONNECTED));
         SendMessage(c->hwndStatus, WM_CLOSE, 0, 0);
         break;
 
@@ -1753,6 +1773,44 @@ OnNeedStr (connection_t *c, UNUSED char *msg)
     WriteStatusLog (c, L"GUI> ", L"Error: Received NEED-STR message -- not implemented", false);
 }
 
+/* Parse the management port and password of a
+ * a running daemon -- useful when the daemon is externally
+ * started (persistent) and we need to use the cached
+ * management interface address parameters to connect to it.
+ */
+static BOOL
+ParseManagementAddress(connection_t *c)
+{
+    /* Not implemented */
+    return false;
+}
+
+/* Stop the connection -- this sets the daemon to exit if
+ * started by us, else instructs the daemon to disconnect and
+ * and wait.
+ */
+static void
+DisconnectDaemon(connection_t *c)
+{
+    if (c->flags & FLAG_DAEMON_PERSISTENT)
+    {
+        if (c->manage.connected)
+        {
+            ManagementCommand(c, "hold on", NULL, regular);
+            ManagementCommand(c, "signal SIGHUP", NULL, regular);
+        }
+        else
+        {
+            OnStop(c, NULL);
+        }
+    }
+    else
+    {
+        SetEvent(c->exit_event);
+        SetTimer(c->hwndStatus, IDT_STOP_TIMER, 15000, NULL);
+    }
+}
+
 /*
  * Close open handles
  */
@@ -1889,7 +1947,6 @@ StatusDialogFunc(HWND hwndDlg, UINT msg, WPARAM wParam, LPARAM lParam)
             return TRUE;
 
         case ID_RESTART:
-            c->state = reconnecting;
             SetFocus(GetDlgItem(c->hwndStatus, ID_EDT_LOG));
             RestartOpenVPN(c);
             return TRUE;
@@ -1921,19 +1978,42 @@ StatusDialogFunc(HWND hwndDlg, UINT msg, WPARAM wParam, LPARAM lParam)
         PostQuitMessage(0);
         break;
 
+    case WM_OVPN_RELEASE:
+        c = (connection_t *) GetProp(hwndDlg, cfgProp);
+        c->state = reconnecting;
+        SetDlgItemText(c->hwndStatus, ID_TXT_STATUS, LoadLocalizedString(IDS_NFO_STATE_RECONNECTING));
+        SetDlgItemTextW(c->hwndStatus, ID_TXT_IP, L"");
+        SetStatusWinIcon(c->hwndStatus, ID_ICO_CONNECTING);
+        OnHold(c, "");
+        break;
+
     case WM_OVPN_STOP:
         c = (connection_t *) GetProp(hwndDlg, cfgProp);
         /* external messages can trigger when we are not ready -- check the state */
-        if (!IsWindowEnabled(GetDlgItem(c->hwndStatus, ID_DISCONNECT)))
+        if (!IsWindowEnabled(GetDlgItem(c->hwndStatus, ID_DISCONNECT))
+            || c->state == onhold)
+        {
             break;
+        }
         c->state = disconnecting;
-        RunDisconnectScript(c, false);
+        if (!(c->flags & FLAG_DAEMON_PERSISTENT))
+        {
+            RunDisconnectScript(c, false);
+        }
         EnableWindow(GetDlgItem(c->hwndStatus, ID_DISCONNECT), FALSE);
         EnableWindow(GetDlgItem(c->hwndStatus, ID_RESTART), FALSE);
         SetMenuStatus(c, disconnecting);
         SetDlgItemText(c->hwndStatus, ID_TXT_STATUS, LoadLocalizedString(IDS_NFO_STATE_WAIT_TERM));
-        SetEvent(c->exit_event);
-        SetTimer(hwndDlg, IDT_STOP_TIMER, 15000, NULL);
+        DisconnectDaemon(c);
+        break;
+
+    case WM_OVPN_DETACH:
+        c = (connection_t *) GetProp(hwndDlg, cfgProp);
+        /* just stop the thread keeping openvpn.exe running */
+        c->state = disconnecting;
+        EnableWindow(GetDlgItem(c->hwndStatus, ID_DISCONNECT), FALSE);
+        EnableWindow(GetDlgItem(c->hwndStatus, ID_RESTART), FALSE);
+        OnStop(c, NULL);
         break;
 
     case WM_OVPN_SUSPEND:
@@ -1962,7 +2042,13 @@ StatusDialogFunc(HWND hwndDlg, UINT msg, WPARAM wParam, LPARAM lParam)
         c = (connection_t *) GetProp(hwndDlg, cfgProp);
         /* external messages can trigger when we are not ready -- check the state */
         if (IsWindowEnabled(GetDlgItem(c->hwndStatus, ID_RESTART)))
+        {
+            c->state = reconnecting;
             ManagementCommand(c, "signal SIGHUP", NULL, regular);
+            SetDlgItemText(c->hwndStatus, ID_TXT_STATUS, LoadLocalizedString(IDS_NFO_STATE_RECONNECTING));
+            SetDlgItemTextW(c->hwndStatus, ID_TXT_IP, L"");
+            SetStatusWinIcon(c->hwndStatus, ID_ICO_CONNECTING);
+        }
         if (!o.silent_connection)
         {
             SetForegroundWindow(c->hwndStatus);
@@ -2037,7 +2123,21 @@ ThreadOpenVPNStatus(void *p)
     while (WM_QUIT != msg.message)
     {
         DWORD res;
-        if (!PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
+        if (wait_event == NULL) /* for persistent connections there is no wait_event */
+        {
+            res = GetMessage(&msg, NULL, 0, 0);
+            if (res == (DWORD) -1)  /* log the error and continue */
+            {
+                MsgToEventLog(EVENTLOG_WARNING_TYPE, L"GetMessage for <%ls> returned error (status=%lu)",
+                              c->config_name, GetLastError());
+                continue;
+            }
+            else if (res == 0) /* WM_QUIT */
+            {
+                break;
+            }
+        }
+        else if (!PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
         {
             if ((res = MsgWaitForMultipleObjectsEx (1, &wait_event, INFINITE, QS_ALLINPUT,
                                          MWMO_ALERTABLE)) == WAIT_OBJECT_0)
@@ -2140,6 +2240,17 @@ static char* PrepareStartJsonRequest(connection_t *c, wchar_t *exit_event_name)
 }
 #endif
 
+/* If state is on hold -- release */
+void
+ReleaseOpenVPN(connection_t *c)
+{
+    if (c->state != onhold)
+    {
+        return;
+    }
+    PostMessage(c->hwndStatus, WM_OVPN_RELEASE, 0, 0);
+}
+
 /* Start a thread to monitor a connection and launch openvpn.exe if required */
 BOOL
 StartOpenVPN(connection_t *c)
@@ -2148,6 +2259,11 @@ StartOpenVPN(connection_t *c)
 
     if (c->hwndStatus)
     {
+        if (c->state == onhold)
+        {
+            ReleaseOpenVPN(c);
+            return true;
+        }
         PrintDebug(L"Connection request when already started -- ignored");
         /* the tread can hang around after disconnect if user has not dismissed any popups */
         if (c->state == disconnected)
@@ -2175,8 +2291,16 @@ StartOpenVPN(connection_t *c)
         return false;
     }
 
+    if (c->flags & FLAG_DAEMON_PERSISTENT)
+    {
+        if (!ParseManagementAddress(c))
+        {
+            TerminateThread(hThread, 1);
+            return false;
+        }
+    }
     /* Launch openvpn.exe using the service or directly */
-    if (!LaunchOpenVPN(c))
+    else if (!LaunchOpenVPN(c))
     {
         TerminateThread(hThread, 1);
         return false;
@@ -2388,6 +2512,20 @@ LaunchOpenVPN(connection_t *c)
 }
 
 
+/* Close the status thread without disconnecting the tunnel.
+ * Meant to be used only on persistent connections which can
+ * stay connected without the GUI tending to it.
+ */
+void
+DetachOpenVPN(connection_t *c)
+{
+   /* currently supported only for persistent connections */
+    if (c->flags & FLAG_DAEMON_PERSISTENT)
+    {
+        PostMessage(c->hwndStatus, WM_OVPN_DETACH, 0, 0);
+    }
+}
+
 void
 StopOpenVPN(connection_t *c)
 {
@@ -2431,10 +2569,18 @@ SuspendOpenVPN(int config)
 void
 RestartOpenVPN(connection_t *c)
 {
-    if (c->hwndStatus)
+    if (c->state == onhold)
+    {
+        ReleaseOpenVPN(c);
+    }
+    else if (c->hwndStatus)
+    {
         PostMessage(c->hwndStatus, WM_OVPN_RESTART, 0, 0);
+    }
     else /* Not started: treat this as a request to connect */
+    {
         StartOpenVPN(c);
+    }
 }
 
 void

diff --git a/openvpn.h b/openvpn.h
@@ -27,8 +27,10 @@
 
 BOOL StartOpenVPN(connection_t *);
 void StopOpenVPN(connection_t *);
+void DetachOpenVPN(connection_t *);
 void SuspendOpenVPN(int config);
 void RestartOpenVPN(connection_t *);
+void ReleaseOpenVPN(connection_t *);
 BOOL CheckVersion();
 void SetStatusWinIcon(HWND hwndDlg, int IconID);
 

diff --git a/options.h b/options.h
@@ -65,6 +65,7 @@ typedef enum {
 /* connection states */
 typedef enum {
     disconnected,
+    onhold,
     connecting,
     reconnecting,
     connected,
@@ -87,6 +88,7 @@ typedef struct {
 #define FLAG_SAVE_AUTH_PASS (1<<5)
 #define FLAG_DISABLE_SAVE_PASS (1<<6)
 #define FLAG_DISABLE_ECHO_MSG  (1<<7)
+#define FLAG_DAEMON_PERSISTENT  (1<<8)
 
 #define CONFIG_VIEW_AUTO      (0)
 #define CONFIG_VIEW_FLAT      (1)

diff --git a/res/openvpn-gui-res-cs.rc b/res/openvpn-gui-res-cs.rc
@@ -359,6 +359,7 @@ Prosím dokončete předchozí autorizační dialog."
     IDS_ERR_CREATE_THREAD_STATUS "CreateThread k zobrazení stavu selhal."
     IDS_NFO_STATE_WAIT_TERM "Aktuální stav: Čekání, než se OpenVPN ukončí…"
     IDS_NFO_STATE_CONNECTED "Aktuální stav: Připojeno"
+    IDS_NFO_STATE_ONHOLD "Current State: On Hold (disconnected)"
     IDS_NFO_NOW_CONNECTED "%ls je nyní připojeno."
     IDS_NFO_ASSIGN_IP "Přiřazená IP: %ls"
     IDS_ERR_CERT_EXPIRED "Spojení nelze navázat, protože certifikát expiroval, nebo není správně nastaven systémový čas."