WPS: Add a workaround for auth/encr type flags mismatches

Some deployed implementations seem to advertise incorrect information
in this attribute. For example, Linksys WRT350N seems to have a
byteorder bug that breaks this negotiation. In order to interoperate
with existing implementations, assume that the Enrollee supports
everything we do.

diff --git a/src/wps/wps_registrar.c b/src/wps/wps_registrar.c
index 9f9e0ac..128bda3 100644 (file)
--- a/src/wps/wps_registrar.c
+++ b/src/wps/wps_registrar.c
@@ -24,6 +24,7 @@
 #include "wps_upnp.h"
 #include "crypto.h"
 
+#define WPS_WORKAROUNDS
 
 struct wps_uuid_pin {
        struct wps_uuid_pin *next;
@@ -1695,7 +1696,21 @@ static int wps_process_auth_type_flags(struct wps_data *wps, const u8 *auth)
                wpa_printf(MSG_DEBUG, "WPS: No match in supported "
                           "authentication types (own 0x%x Enrollee 0x%x)",
                           wps->wps->auth_types, auth_types);
+#ifdef WPS_WORKAROUNDS
+               /*
+                * Some deployed implementations seem to advertise incorrect
+                * information in this attribute. For example, Linksys WRT350N
+                * seems to have a byteorder bug that breaks this negotiation.
+                * In order to interoperate with existing implementations,
+                * assume that the Enrollee supports everything we do.
+                */
+               wpa_printf(MSG_DEBUG, "WPS: Workaround - assume Enrollee "
+                          "does not advertise supported authentication types "
+                          "correctly");
+               wps->auth_type = wps->wps->auth_types;
+#else /* WPS_WORKAROUNDS */
                return -1;
+#endif /* WPS_WORKAROUNDS */
        }
 
        return 0;
@@ -1719,8 +1734,23 @@ static int wps_process_encr_type_flags(struct wps_data *wps, const u8 *encr)
        wps->encr_type = wps->wps->encr_types & encr_types;
        if (wps->encr_type == 0) {
                wpa_printf(MSG_DEBUG, "WPS: No match in supported "
-                          "encryption types");
+                          "encryption types (own 0x%x Enrollee 0x%x)",
+                          wps->wps->encr_types, encr_types);
+#ifdef WPS_WORKAROUNDS
+               /*
+                * Some deployed implementations seem to advertise incorrect
+                * information in this attribute. For example, Linksys WRT350N
+                * seems to have a byteorder bug that breaks this negotiation.
+                * In order to interoperate with existing implementations,
+                * assume that the Enrollee supports everything we do.
+                */
+               wpa_printf(MSG_DEBUG, "WPS: Workaround - assume Enrollee "
+                          "does not advertise supported encryption types "
+                          "correctly");
+               wps->encr_type = wps->wps->encr_types;
+#else /* WPS_WORKAROUNDS */
                return -1;
+#endif /* WPS_WORKAROUNDS */
        }
 
        return 0;