Fix handling of ntor handshakes received via CREATE cells

Fixes bug 7959; bugfix on 0.2.4.8-alpha.

changes/bug7959

@@ -0,0 +1,6 @@
+  o Major bugfixes:
+    - Fix backward compatibility logic when receiving an embedded ntor
+      handshake tunneled in a CREATE cell. This clears up the "Bug: couldn't
+      format CREATED cell" warning. Fix for bug 7959; bugfix on
+      0.2.4.8-alpha.
+

src/or/onion.c

@@ -560,7 +560,8 @@ check_created_cell(const created_cell_t *cell)
 {
   switch (cell->cell_type) {
   case CELL_CREATED:
-    if (cell->handshake_len != TAP_ONIONSKIN_REPLY_LEN)
+    if (cell->handshake_len != TAP_ONIONSKIN_REPLY_LEN &&
+        cell->handshake_len != NTOR_REPLY_LEN)
       return -1;
     break;
   case CELL_CREATED_FAST: