diff --git a/ChangeLog b/ChangeLog
index 8ec42181968054833538c041485a66aa1e618047..b69a29c2d3dbf3d735664af72525610f2f2ffb25 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 2014-04-11  Niels Möller  <nisse@lysator.liu.se>
 
+	* testsuite/testutils.c (test_aead): Use aead->digest_size.
+
 	* configure.ac: Skip GMP tests if public key support is disabled.
 
 	* eax.c (block16_xor): Fixed bug effecting 32-bit platforms.
diff --git a/testsuite/testutils.c b/testsuite/testutils.c
index 4fa3a18d446ccdb0e761aaca9070cb1f78e7b258..b273bece632cc78c92fa5325d19759e1fbc39b8b 100644
--- a/testsuite/testutils.c
+++ b/testsuite/testutils.c
@@ -478,19 +478,19 @@ test_aead(const struct nettle_aead *aead,
 {
   void *ctx = xalloc(aead->context_size);
   uint8_t *data;
-  uint8_t *buffer = xalloc(aead->block_size);
+  uint8_t *buffer = xalloc(aead->digest_size);
   size_t length;
 
   ASSERT (cleartext->length == ciphertext->length);
   length = cleartext->length;
 
   ASSERT (key->length == aead->key_size);
-  ASSERT (digest->length <= aead->block_size);
+  ASSERT (digest->length <= aead->digest_size);
 
   data = xalloc(length);
   
   /* encryption */
-  memset(buffer, 0, aead->block_size);
+  memset(buffer, 0, aead->digest_size);
   aead->set_encrypt_key(ctx, key->data);
 
   if (nonce->length != aead->nonce_size)
@@ -513,7 +513,7 @@ test_aead(const struct nettle_aead *aead,
   ASSERT(MEMEQ(digest->length, buffer, digest->data));
 
   /* decryption */
-  memset(buffer, 0, aead->block_size);
+  memset(buffer, 0, aead->digest_size);
 
   aead->set_decrypt_key(ctx, key->data);