From a0019ec79cc9c3a5c8fc2b4c0eda2da0f7d153f0 Mon Sep 17 00:00:00 2001
From: Pavel Pautov <37922380+p-pautov@users.noreply.github.com>
Date: Tue, 17 Apr 2018 17:05:20 -0700
Subject: [PATCH] Fallback to RDG RPC transport only if server does not support
 RDG HTTP and error out in other cases - invalid RDG SSL cert, bad
 credentials, PAA failue, etc.

---
 libfreerdp/core/gateway/rdg.c | 16 ++++++++++++----
 libfreerdp/core/gateway/rdg.h |  3 +--
 libfreerdp/core/transport.c   |  5 +++--
 3 files changed, 16 insertions(+), 8 deletions(-)
 mode change 100644 => 100755 libfreerdp/core/transport.c

diff --git a/libfreerdp/core/gateway/rdg.c b/libfreerdp/core/gateway/rdg.c
index 3dab0f4f1..2eac65609 100755
--- a/libfreerdp/core/gateway/rdg.c
+++ b/libfreerdp/core/gateway/rdg.c
@@ -733,7 +733,7 @@ static BOOL rdg_tls_connect(rdpRdg* rdg, rdpTls* tls, const char* peerAddress, i
 }
 
 static BOOL rdg_establish_data_connection(rdpRdg* rdg, rdpTls* tls,
-		const char* method, const char* peerAddress, int timeout)
+		const char* method, const char* peerAddress, int timeout, BOOL* rpcFallback)
 {
 	HttpResponse* response = NULL;
 	int statusCode;
@@ -754,6 +754,14 @@ static BOOL rdg_establish_data_connection(rdpRdg* rdg, rdpTls* tls,
 		if (!response)
 			return FALSE;
 
+		if (response->StatusCode == HTTP_STATUS_NOT_FOUND)
+		{
+			WLog_INFO(TAG, "RD Gateway does not support HTTP transport.");
+			if (rpcFallback) *rpcFallback = TRUE;
+			http_response_free(response);
+			return FALSE;
+		}
+
 		if (!rdg_handle_ntlm_challenge(rdg->ntlm, response))
 		{
 			http_response_free(response);
@@ -824,7 +832,7 @@ static BOOL rdg_tunnel_connect(rdpRdg* rdg)
 	return TRUE;
 }
 
-BOOL rdg_connect(rdpRdg* rdg, const char* hostname, UINT16 port, int timeout)
+BOOL rdg_connect(rdpRdg* rdg, int timeout, BOOL* rpcFallback)
 {
 	BOOL status;
 	int outConnSocket = 0;
@@ -832,7 +840,7 @@ BOOL rdg_connect(rdpRdg* rdg, const char* hostname, UINT16 port, int timeout)
 	assert(rdg != NULL);
 
 	status = rdg_establish_data_connection(
-			rdg, rdg->tlsOut, "RDG_OUT_DATA", NULL, timeout);
+			rdg, rdg->tlsOut, "RDG_OUT_DATA", NULL, timeout, rpcFallback);
 
 	if (status)
 	{
@@ -843,7 +851,7 @@ BOOL rdg_connect(rdpRdg* rdg, const char* hostname, UINT16 port, int timeout)
 		peerAddress = freerdp_tcp_get_peer_address(outConnSocket);
 
 		status = rdg_establish_data_connection(
-				rdg, rdg->tlsIn, "RDG_IN_DATA", peerAddress, timeout);
+				rdg, rdg->tlsIn, "RDG_IN_DATA", peerAddress, timeout, NULL);
 
 		free(peerAddress);
 	}
diff --git a/libfreerdp/core/gateway/rdg.h b/libfreerdp/core/gateway/rdg.h
index 2dfbbc5c5..f4fa95c11 100755
--- a/libfreerdp/core/gateway/rdg.h
+++ b/libfreerdp/core/gateway/rdg.h
@@ -138,8 +138,7 @@ struct rdp_rdg
 FREERDP_LOCAL rdpRdg* rdg_new(rdpTransport* transport);
 FREERDP_LOCAL void rdg_free(rdpRdg* rdg);
 
-FREERDP_LOCAL BOOL rdg_connect(rdpRdg* rdg, const char* hostname, UINT16 port,
-                               int timeout);
+FREERDP_LOCAL BOOL rdg_connect(rdpRdg* rdg, int timeout, BOOL* rpcFallback);
 FREERDP_LOCAL DWORD rdg_get_event_handles(rdpRdg* rdg, HANDLE* events,
         DWORD count);
 
diff --git a/libfreerdp/core/transport.c b/libfreerdp/core/transport.c
old mode 100644
new mode 100755
index ad44e0a17..59ee8cf3d
--- a/libfreerdp/core/transport.c
+++ b/libfreerdp/core/transport.c
@@ -354,6 +354,7 @@ BOOL transport_connect(rdpTransport* transport, const char* hostname,
 	rdpSettings* settings = transport->settings;
 	rdpContext* context = transport->context;
 	transport->async = settings->AsyncTransport;
+	BOOL rpcFallback = !settings->GatewayHttpTransport;
 
 	if (transport->GatewayEnabled)
 	{
@@ -364,7 +365,7 @@ BOOL transport_connect(rdpTransport* transport, const char* hostname,
 			if (!transport->rdg)
 				return FALSE;
 
-			status = rdg_connect(transport->rdg, hostname, port, timeout);
+			status = rdg_connect(transport->rdg, timeout, &rpcFallback);
 
 			if (status)
 			{
@@ -380,7 +381,7 @@ BOOL transport_connect(rdpTransport* transport, const char* hostname,
 			}
 		}
 
-		if (!status && settings->GatewayRpcTransport)
+		if (!status && settings->GatewayRpcTransport && rpcFallback)
 		{
 			transport->tsg = tsg_new(transport);