TLS: new method to specify SSL/TLS version

SSL/TLS protocols only listed in ssl_protocols should be used.
The name "ssl_protocols" comes from nginx.

Resolves #428.

2 files changed, 34 insertions, 3 deletions

diff --git a/libxrdp/xrdp_rdp.c b/libxrdp/xrdp_rdp.c
index 5159ba5b..bdb552c8 100644
--- a/libxrdp/xrdp_rdp.c
+++ b/libxrdp/xrdp_rdp.c
@@ -18,6 +18,7 @@
  * rdp layer
  */
 
+#include <openssl/ssl.h>
 #include "libxrdp.h"
 #include "log.h"
 
@@ -44,6 +45,8 @@ xrdp_rdp_read_config(struct xrdp_client_info *client_info)
     char *item = (char *)NULL;
     char *value = (char *)NULL;
     char cfg_file[256];
+    char *tmp = (char *)NULL;
+    int tmp_length = 0;
 
     /* initialize (zero out) local variables: */
     g_memset(cfg_file, 0, sizeof(char) * 256);
@@ -160,9 +163,37 @@ xrdp_rdp_read_config(struct xrdp_client_info *client_info)
                 client_info->use_fast_path = 0;
             }
         }
-        else if (g_strcasecmp(item, "disableSSLv3") == 0)
+        else if (g_strcasecmp(item, "ssl_protocols") == 0)
         {
-            client_info->disableSSLv3 = g_text2bool(value);
+            /* put leading/trailing space to properly detect "TLSv1" without regex */
+            tmp_length = g_strlen(value) + 3;
+            tmp = g_new(char, tmp_length);
+            g_snprintf(tmp, tmp_length, "%s%s%s", " ", value, " ");
+
+	    /* disable all protocols first, enable later */
+            client_info->ssl_protocols =
+                SSL_OP_NO_SSLv3 | SSL_OP_NO_TLSv1 | SSL_OP_NO_TLSv1_1 | SSL_OP_NO_TLSv1_2;
+
+            if (g_pos(tmp, " TLSv1.2 ") >= 0)
+            {
+                log_message(LOG_LEVEL_DEBUG, "TLSv1.2 enabled");
+                client_info->ssl_protocols &= ~SSL_OP_NO_TLSv1_2;
+            }
+            if (g_pos(tmp, " TLSv1.1 ") >= 0)
+            {
+                log_message(LOG_LEVEL_DEBUG, "TLSv1.1 enabled");
+                client_info->ssl_protocols &= ~SSL_OP_NO_TLSv1_1;
+            }
+            if (g_pos(tmp, " TLSv1 ") >= 0)
+            {
+                log_message(LOG_LEVEL_DEBUG, "TLSv1 enabled");
+                client_info->ssl_protocols &= ~SSL_OP_NO_TLSv1;
+            }
+            if (g_pos(tmp, " SSLv3 ") >= 0)
+            {
+                log_message(LOG_LEVEL_DEBUG, "SSLv3 enabled");
+                client_info->ssl_protocols &= ~SSL_OP_NO_SSLv3;
+            }
         }
         else if (g_strcasecmp(item, "tls_ciphers") == 0)
         {
diff --git a/libxrdp/xrdp_sec.c b/libxrdp/xrdp_sec.c
index 422acfe2..b5d33863 100644
--- a/libxrdp/xrdp_sec.c
+++ b/libxrdp/xrdp_sec.c
@@ -2254,7 +2254,7 @@ xrdp_sec_incoming(struct xrdp_sec *self)
         if (trans_set_tls_mode(self->mcs_layer->iso_layer->trans,
                 self->rdp_layer->client_info.key_file,
                 self->rdp_layer->client_info.certificate,
-                self->rdp_layer->client_info.disableSSLv3,
+                self->rdp_layer->client_info.ssl_protocols,
                 self->rdp_layer->client_info.tls_ciphers) != 0)
         {
             g_writeln("xrdp_sec_incoming: trans_set_tls_mode failed");