Test the OCB-AES reference implementation

This tests cryptographic primitives implemented by others.  It uses the same
interfaces and indeed the same compiled object code as the Mosh client and
server.  It does not particularly test any code written for the Mosh project.

src/tests/test_utils.cc

@@ -0,0 +1,34 @@
+/*
+    Mosh: the mobile shell
+    Copyright 2012 Keith Winstein
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdio.h>
+
+#include "test_utils.h"
+
+void hexdump( const void *buf, size_t len, const char *name ) {
+  const unsigned char *data = (const unsigned char *) buf;
+  printf( DUMP_NAME_FMT, name );
+  for ( size_t i = 0; i < len; i++ ) {
+    printf( "%02x", data[ i ] );
+  }
+  printf( "\n" );
+}
+
+void hexdump( const Crypto::AlignedBuffer &buf, const char *name ) {
+  hexdump( buf.data(), buf.len(), name );
+}