xfreerdp: add --authonly switch to xfreerdp client

Signed-off-by: Rex Tsai <chihchun@kalug.linux.org.tw>

client/X11/xfreerdp.1.xml

@@ -288,6 +288,14 @@
           </para>
         </listitem>
       </varlistentry>
+      <varlistentry>
+        <term>--authonly</term>
+        <listitem>
+          <para>
+            Only authenticates. This is useful to test your credentials (username and password). Returns status code 0 if the client can connect, 1 otherwise. Requires a username, password and connection host at the command line.
+          </para>
+        </listitem>
+      </varlistentry>
       <varlistentry>
         <term>--no-fastpath</term>
         <listitem>

client/X11/xfreerdp.c

@@ -479,7 +479,7 @@ boolean xf_pre_connect(freerdp* instance)
 	if (arg_parse_result < 0)
 	{
 		if (arg_parse_result == FREERDP_ARGS_PARSE_FAILURE)
-			printf("failed to parse arguments.\n");
+			fprintf(stderr, "%s:%d: failed to parse arguments.\n", __FILE__, __LINE__);
 		
 		exit(XF_EXIT_PARSE_ARGUMENTS);
 	}
@@ -521,6 +521,22 @@ boolean xf_pre_connect(freerdp* instance)
 
 	freerdp_channels_pre_connect(xfi->_context->channels, instance);
 
+
+  if (settings->authentication_only) {
+		/* Check --authonly has a username and password. */
+		if (settings->username == NULL ) {
+			fprintf(stderr, "--authonly, but no -u username. Please provide one.\n");
+			exit(1);
+		}
+		if (settings->password == NULL ) {
+			fprintf(stderr, "--authonly, but no -p password. Please provide one.\n");
+			exit(1);
+		}
+		fprintf(stderr, "%s:%d: Authenication only. Don't connect to X.\n", __FILE__, __LINE__);
+		// Avoid XWindows initialization and configuration below.
+		return true;
+	}
+
 	xfi->display = XOpenDisplay(NULL);
 
 	if (xfi->display == NULL)
@@ -1072,6 +1088,11 @@ int xfreerdp_run(freerdp* instance)
 		xf_free(((xfContext*) instance->context)->xfi);
 		return XF_EXIT_CONN_FAILED;
 	}
+	/* Connection succeeded. --authonly ? */
+	if (instance->settings->authentication_only) {
+		freerdp_disconnect(instance);
+    exit(0);
+	}
 
 	xfi = ((xfContext*) instance->context)->xfi;
 	channels = instance->context->channels;

include/freerdp/settings.h

@@ -293,7 +293,8 @@ struct rdp_settings
 	ALIGN64 char* tsg_username; /* 66 */
 	ALIGN64 char* tsg_password; /* 67 */
 	ALIGN64 boolean local; /* 68 */
-	ALIGN64 uint64 paddingC[80 - 69]; /* 69 */
+	ALIGN64 boolean authentication_only; /* 69 */
+	ALIGN64 uint64 paddingC[80 - 70]; /* 70 */
 
 	/* User Interface Parameters */
 	ALIGN64 boolean sw_gdi; /* 80 */

libfreerdp-core/freerdp.c

@@ -61,11 +61,16 @@ boolean freerdp_connect(freerdp* instance)
 		if(!connectErrorCode){
 			connectErrorCode = PREECONNECTERROR;
 		}
-		printf("freerdp_pre_connect failed\n");
+		fprintf(stderr, "%s:%d: freerdp_pre_connect failed\n", __FILE__, __LINE__);
 		return false;
 	}
 
 	status = rdp_client_connect(rdp);
+	// --authonly tests the connection without a UI
+	if (instance->settings->authentication_only) {
+		fprintf(stderr, "%s:%d: Authentication only, exit status %d\n", __FILE__, __LINE__, !status);
+		return true;
+	}
 
 	if (status)
 	{

libfreerdp-core/settings.c

@@ -73,6 +73,7 @@ rdpSettings* settings_new(void* instance)
 		settings->encryption_level = ENCRYPTION_LEVEL_NONE;
 
 		settings->authentication = true;
+		settings->authentication_only = false;
 
 		settings->received_caps = xzalloc(32);
 		settings->order_support = xzalloc(32);

libfreerdp-utils/args.c

@@ -81,6 +81,7 @@ int freerdp_parse_args(rdpSettings* settings, int argc, char** argv,
 				"  --app: RemoteApp connection. This implies -g workarea\n"
 				"  --ext: load an extension\n"
 				"  --no-auth: disable authentication\n"
+				"  --authonly: authentication only, no UI\n"
 				"  --no-fastpath: disable fast-path\n"
 				"  --no-motion: don't send mouse motion events\n"
 				"  --gdi: graphics rendering (hw, sw)\n"
@@ -306,6 +307,10 @@ int freerdp_parse_args(rdpSettings* settings, int argc, char** argv,
 		{
 			settings->authentication = false;
 		}
+		else if (strcmp("--authonly", argv[index]) == 0)
+		{
+			settings->authentication_only = true;
+		}
 		else if (strcmp("--ignore-certificate", argv[index]) == 0)
 		{
 			settings->ignore_certificate = true;