WPS UPnP: Check os_get_random() result

This makes the implementation more consistent (CID 72705).

Signed-off-by: Jouni Malinen <j@w1.fi>

diff --git a/src/wps/wps_upnp.c b/src/wps/wps_upnp.c
index 993db838989a3c0c99ea826000997886fb2357f6..933d7340ee8ec91d602c23ab1ffe5937949a1783 100644 (file)
--- a/src/wps/wps_upnp.c
+++ b/src/wps/wps_upnp.c
@@ -251,13 +251,16 @@ void format_date(struct wpabuf *buf)
  * use for constructing UUIDs for subscriptions. Presumably any method from
  * rfc4122 is good enough; I've chosen random number method.
  */
-static void uuid_make(u8 uuid[UUID_LEN])
+static int uuid_make(u8 uuid[UUID_LEN])
 {
-       os_get_random(uuid, UUID_LEN);
+       if (os_get_random(uuid, UUID_LEN) < 0)
+               return -1;
 
        /* Replace certain bits as specified in rfc4122 or X.667 */
        uuid[6] &= 0x0f; uuid[6] |= (4 << 4);   /* version 4 == random gen */
        uuid[8] &= 0x3f; uuid[8] |= 0x80;
+
+       return 0;
 }
 
 
@@ -716,7 +719,10 @@ struct subscription * subscription_start(struct upnp_wps_device_sm *sm,
 
        s->sm = sm;
        s->timeout_time = expire;
-       uuid_make(s->uuid);
+       if (uuid_make(s->uuid) < 0) {
+               subscription_destroy(s);
+               return NULL;
+       }
        subscr_addr_list_create(s, callback_urls);
        if (dl_list_empty(&s->addr_list)) {
                wpa_printf(MSG_DEBUG, "WPS UPnP: No valid callback URLs in "