use NULL as flag for evaluation of query, ensure we pass non-NULL for reply_block to evaluate reply even if reply is zero bytes long

3 files changed, 7 insertions, 3 deletions

diff --git a/src/dht/gnunet-service-dht_datacache.c b/src/dht/gnunet-service-dht_datacache.c
index 9b4dace67..74fa1cc29 100644
--- a/src/dht/gnunet-service-dht_datacache.c
+++ b/src/dht/gnunet-service-dht_datacache.c
@@ -170,9 +170,14 @@ datacache_get_iterator (void *cls,
                         unsigned int put_path_length,
                         const struct GNUNET_PeerIdentity *put_path)
 {
+  static char non_null;
   struct GetRequestContext *ctx = cls;
   enum GNUNET_BLOCK_EvaluationResult eval;
 
+  if ( (NULL == data) &&
+       (0 == data_size) )
+    data = &non_null; /* point anywhere, but not to NULL */
+
   eval
     = GNUNET_BLOCK_evaluate (GDS_block_context,
                              type,
diff --git a/src/dht/plugin_block_dht.c b/src/dht/plugin_block_dht.c
index 8bb533961..4256a0fe6 100644
--- a/src/dht/plugin_block_dht.c
+++ b/src/dht/plugin_block_dht.c
@@ -75,8 +75,7 @@ block_plugin_dht_evaluate (void *cls,
     GNUNET_break_op (0);
     return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
   }
-  if ( (NULL == reply_block) ||
-       (0 == reply_block_size) )
+  if (NULL == reply_block)
     return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
   if (reply_block_size < sizeof (struct GNUNET_MessageHeader))
   {
diff --git a/src/dns/plugin_block_dns.c b/src/dns/plugin_block_dns.c
index dc339dd25..8c6ec93ee 100644
--- a/src/dns/plugin_block_dns.c
+++ b/src/dns/plugin_block_dns.c
@@ -69,7 +69,7 @@ block_plugin_dns_evaluate (void *cls,
     if (0 != xquery_size)
       return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
 
-    if (0 == reply_block_size)
+    if (NULL == reply_block)
       return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
 
     if (sizeof (struct GNUNET_DNS_Advertisement) != reply_block_size)