Add ct fuzzer.

Reviewed-by: NRich Salz <rsalz@openssl.org>

.gitignore

@@ -63,6 +63,7 @@ Makefile
 /fuzz/bndiv
 /fuzz/conf
 /fuzz/cms
+/fuzz/ct
 /fuzz/server
 /fuzz/x509
 /test/sha256t
@@ -85,6 +86,7 @@ Makefile
 *.dylib*
 *.dll*
 *.exe
+*.pyc
 # Exceptions
 !/test/bctest
 !/crypto/des/times/486-50.sol

fuzz/ct.c

+/*
+ * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL licenses, (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * https://www.openssl.org/source/license.html
+ * or in the file LICENSE in the source distribution.
+ */
+
+/*
+ * Fuzz the SCT parser.
+ */
+
+#include <stdio.h>
+#include <openssl/ct.h>
+#include "fuzzer.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *buf, size_t len) {
+    const uint8_t **pp = &buf;
+    STACK_OF(SCT) *scts = d2i_SCT_LIST(NULL, pp, len);
+    SCT_LIST_free(scts);
+    return 0;
+}