GUACAMOLE-221: Merge rely on FreeRDP error code if no RDP disconnect reason is available.

src/protocols/rdp/error.c

@@ -18,14 +18,119 @@
  */
 
 #include "error.h"
-#include "rdp.h"
 
 #include <freerdp/freerdp.h>
 #include <guacamole/client.h>
 #include <guacamole/protocol.h>
 #include <guacamole/socket.h>
+#include <winpr/wtypes.h>
 
-void guac_rdp_client_abort(guac_client* client) {
+/**
+ * Translates the error code returned by freerdp_get_last_error() for the given
+ * RDP instance into a Guacamole status code and human-readable message. If no
+ * error was reported, a successful error code and message will be assigned.
+ *
+ * @param rdp_inst
+ *     The FreeRDP client instance handling the RDP connection that failed.
+ *
+ * @param status
+ *     Pointer to the variable that should receive the guac_protocol_status
+ *     value equivalent to the error returned by freerdp_get_last_error().
+ *
+ * @param message
+ *     Pointer to the variable that should receive a static human-readable
+ *     message generally describing the error returned by
+ *     freerdp_get_last_error().
+ */
+static void guac_rdp_translate_last_error(freerdp* rdp_inst,
+        guac_protocol_status* status, const char** message) {
+
+    UINT32 last_error = freerdp_get_last_error(rdp_inst->context);
+    switch (last_error) {
+
+        /* Normal disconnect */
+        case FREERDP_ERROR_NONE:
+        case FREERDP_ERROR_SUCCESS:
+            *status = GUAC_PROTOCOL_STATUS_SUCCESS;
+            *message = "Disconnected.";
+            break;
+
+        /* Account expired */
+        case FREERDP_ERROR_CONNECT_ACCOUNT_EXPIRED:
+        case FREERDP_ERROR_CONNECT_PASSWORD_CERTAINLY_EXPIRED:
+        case FREERDP_ERROR_CONNECT_PASSWORD_EXPIRED:
+        case FREERDP_ERROR_CONNECT_PASSWORD_MUST_CHANGE:
+        case FREERDP_ERROR_SERVER_FRESH_CREDENTIALS_REQUIRED:
+            *status = GUAC_PROTOCOL_STATUS_CLIENT_FORBIDDEN;
+            *message = "Credentials expired.";
+            break;
+
+        /* Security negotiation failed */
+        case FREERDP_ERROR_SECURITY_NEGO_CONNECT_FAILED:
+            *status = GUAC_PROTOCOL_STATUS_CLIENT_UNAUTHORIZED;
+            *message = "Security negotiation failed (wrong security type?)";
+            break;
+
+        /* Access denied */
+        case FREERDP_ERROR_CONNECT_ACCESS_DENIED:
+        case FREERDP_ERROR_CONNECT_ACCOUNT_DISABLED:
+        case FREERDP_ERROR_CONNECT_ACCOUNT_LOCKED_OUT:
+        case FREERDP_ERROR_CONNECT_ACCOUNT_RESTRICTION:
+        case FREERDP_ERROR_CONNECT_CLIENT_REVOKED:
+        case FREERDP_ERROR_CONNECT_LOGON_TYPE_NOT_GRANTED:
+        case FREERDP_ERROR_INSUFFICIENT_PRIVILEGES:
+        case FREERDP_ERROR_SERVER_DENIED_CONNECTION:
+        case FREERDP_ERROR_SERVER_INSUFFICIENT_PRIVILEGES:
+            *status = GUAC_PROTOCOL_STATUS_CLIENT_UNAUTHORIZED;
+            *message = "Access denied by server (account locked/disabled?)";
+            break;
+
+        /* General, unspecified authentication failure */
+        case FREERDP_ERROR_AUTHENTICATION_FAILED:
+        case FREERDP_ERROR_CONNECT_LOGON_FAILURE:
+        case FREERDP_ERROR_CONNECT_NO_OR_MISSING_CREDENTIALS:
+        case FREERDP_ERROR_CONNECT_WRONG_PASSWORD:
+            *status = GUAC_PROTOCOL_STATUS_CLIENT_UNAUTHORIZED;
+            *message = "Authentication failure (invalid credentials?)";
+            break;
+
+        /* SSL/TLS connection failed */
+        case FREERDP_ERROR_TLS_CONNECT_FAILED:
+            *status = GUAC_PROTOCOL_STATUS_UPSTREAM_NOT_FOUND;
+            *message = "SSL/TLS connection failed (untrusted/self-signed certificate?)";
+            break;
+
+        /* DNS lookup failed */
+        case FREERDP_ERROR_DNS_ERROR:
+        case FREERDP_ERROR_DNS_NAME_NOT_FOUND:
+            *status = GUAC_PROTOCOL_STATUS_UPSTREAM_NOT_FOUND;
+            *message = "DNS lookup failed (incorrect hostname?)";
+            break;
+
+        case FREERDP_ERROR_CONNECT_TRANSPORT_FAILED:
+            *status = GUAC_PROTOCOL_STATUS_UPSTREAM_NOT_FOUND;
+            *message = "Server refused connection (wrong security type?)";
+            break;
+
+        /* Connection failed */
+        case FREERDP_ERROR_CONNECT_CANCELLED:
+        case FREERDP_ERROR_CONNECT_FAILED:
+        case FREERDP_ERROR_CONNECT_KDC_UNREACHABLE:
+        case FREERDP_ERROR_MCS_CONNECT_INITIAL_ERROR:
+            *status = GUAC_PROTOCOL_STATUS_UPSTREAM_NOT_FOUND;
+            *message = "Connection failed (server unreachable?)";
+            break;
+
+        /* All other errors */
+        default:
+            *status = GUAC_PROTOCOL_STATUS_UPSTREAM_ERROR;
+            *message = "Upstream error.";
+
+    }
+
+}
+
+void guac_rdp_client_abort(guac_client* client, freerdp* rdp_inst) {
 
     /*
      * NOTE: The RDP status codes translated here are documented within
@@ -35,9 +140,6 @@ void guac_rdp_client_abort(guac_client* client) {
      * https://msdn.microsoft.com/en-us/library/cc240544.aspx
      */
 
-    guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
-    freerdp* rdp_inst = rdp_client->rdp_inst;
-
     guac_protocol_status status;
     const char* message;
 
@@ -47,10 +149,9 @@ void guac_rdp_client_abort(guac_client* client) {
     /* Translate reason code into Guacamole protocol status */
     switch (error_info) {
 
-        /* Normal disconnect */
+        /* Possibly-normal disconnect, depending on freerdp_get_last_error() */
         case 0x0: /* ERRINFO_SUCCESS */
-            status = GUAC_PROTOCOL_STATUS_SUCCESS;
+            guac_rdp_translate_last_error(rdp_inst, &status, &message);
-            message = "Disconnected.";
             break;
 
         /* Forced disconnect (possibly by admin) */
@@ -129,8 +230,8 @@ void guac_rdp_client_abort(guac_client* client) {
     }
 
     /* Log human-readable description of disconnect at info level */
-    guac_client_log(client, GUAC_LOG_INFO, "RDP server closed connection: %s",
+    guac_client_log(client, GUAC_LOG_INFO, "RDP server closed/refused "
-            message);
+            "connection: %s", message);
 
     /* Log internal disconnect reason code at debug level */
     if (error_info)

src/protocols/rdp/error.h

@@ -20,17 +20,22 @@
 #ifndef GUAC_RDP_ERROR_H
 #define GUAC_RDP_ERROR_H
 
+#include <freerdp/freerdp.h>
 #include <guacamole/client.h>
 
 /**
- * Stops the current connection due to the RDP server disconnecting. If the RDP
+ * Stops the current connection due to the RDP server disconnecting or the
- * server provided a reason for disconnecting, that reason will be logged, and
+ * connection attempt failing. If the RDP server or FreeRDP provided a reason
- * an appropriate error code will be sent to the Guacamole client.
+ * for for the failure/disconnect, that reason will be logged, and an
+ * appropriate error code will be sent to the Guacamole client.
  *
  * @param client
  *     The Guacamole client to disconnect.
+ *
+ * @param rdp_inst
+ *     The FreeRDP client instance handling the RDP connection that failed.
  */
-void guac_rdp_client_abort(guac_client* client);
+void guac_rdp_client_abort(guac_client* client, freerdp* rdp_inst);
 
 #endif
 

src/protocols/rdp/rdp.c

@@ -461,8 +461,7 @@ static int guac_rdp_handle_connection(guac_client* client) {
 
     /* Connect to RDP server */
     if (!freerdp_connect(rdp_inst)) {
-        guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_NOT_FOUND,
+        guac_rdp_client_abort(client, rdp_inst);
-                "Error connecting to RDP server");
         goto fail;
     }
 
@@ -542,7 +541,7 @@ static int guac_rdp_handle_connection(guac_client* client) {
 
         /* Close connection cleanly if server is disconnecting */
         if (connection_closing)
-            guac_rdp_client_abort(client);
+            guac_rdp_client_abort(client, rdp_inst);
 
         /* If a low-level connection error occurred, fail */
         else if (wait_result < 0)