From f0d0105d5067b1224bb060e43cbd6bf9734f12b6 Mon Sep 17 00:00:00 2001
From: akallabeth <akallabeth@posteo.net>
Date: Mon, 28 Oct 2024 08:21:08 +0100
Subject: [PATCH] [client,common] tighten /vmconnect checks

Fixes #5300:
* abort if +/-nego is used, /vmconnect overrides these.
* only set custom port if no /port or /v:host:port is in use allowing
  overriding default port
---
 client/common/cmdline.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/client/common/cmdline.c b/client/common/cmdline.c
index a43ae5073..31dbf71cc 100644
--- a/client/common/cmdline.c
+++ b/client/common/cmdline.c
@@ -2604,7 +2604,12 @@ static int parse_vmconnect_options(rdpSettings* settings, const COMMAND_LINE_ARG
 
 	if (!freerdp_settings_set_bool(settings, FreeRDP_VmConnectMode, TRUE))
 		return COMMAND_LINE_ERROR;
-	if (!freerdp_settings_set_uint32(settings, FreeRDP_ServerPort, 2179))
+
+	UINT32 port = freerdp_settings_get_uint32(settings, FreeRDP_ServerPort);
+	if (port == 3389)
+		port = 2179;
+
+	if (!freerdp_settings_set_uint32(settings, FreeRDP_ServerPort, port))
 		return COMMAND_LINE_ERROR;
 	if (!freerdp_settings_set_bool(settings, FreeRDP_NegotiateSecurityLayer, FALSE))
 		return COMMAND_LINE_ERROR;
@@ -5466,6 +5471,16 @@ static int freerdp_client_settings_parse_command_line_arguments_int(
 			return fail_at(arg, COMMAND_LINE_ERROR);
 	}
 
+	if (freerdp_settings_get_bool(settings, FreeRDP_VmConnectMode))
+	{
+		const COMMAND_LINE_ARGUMENT_A* nego = CommandLineFindArgumentA(largs, "nego");
+		if (nego)
+			return fail_at(arg, COMMAND_LINE_ERROR);
+
+		const UINT32 port = freerdp_settings_get_uint32(settings, FreeRDP_ServerPort);
+		WLog_INFO(TAG, "/vmconnect uses custom port %" PRIu32, port);
+	}
+
 	fill_credential_strings(largs);
 
 	return status;