tests: Add fuzzing harness for classes/functions in cuckoocache.h

1 files changed, 49 insertions, 0 deletions

diff --git a/src/test/fuzz/cuckoocache.cpp b/src/test/fuzz/cuckoocache.cpp
new file mode 100644
index 0000000000..f674efe1b1
--- /dev/null
+++ b/src/test/fuzz/cuckoocache.cpp
@@ -0,0 +1,49 @@
+// Copyright (c) 2020 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <cuckoocache.h>
+#include <optional.h>
+#include <script/sigcache.h>
+#include <test/fuzz/FuzzedDataProvider.h>
+#include <test/fuzz/fuzz.h>
+#include <test/fuzz/util.h>
+#include <test/util/setup_common.h>
+
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace {
+FuzzedDataProvider* fuzzed_data_provider_ptr = nullptr;
+
+struct RandomHasher {
+    template <uint8_t>
+    uint32_t operator()(const bool& /* unused */) const
+    {
+        assert(fuzzed_data_provider_ptr != nullptr);
+        return fuzzed_data_provider_ptr->ConsumeIntegral<uint32_t>();
+    }
+};
+} // namespace
+
+void test_one_input(const std::vector<uint8_t>& buffer)
+{
+    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
+    fuzzed_data_provider_ptr = &fuzzed_data_provider;
+    CuckooCache::cache<bool, RandomHasher> cuckoo_cache{};
+    if (fuzzed_data_provider.ConsumeBool()) {
+        const size_t megabytes = fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 16);
+        cuckoo_cache.setup_bytes(megabytes << 20);
+    } else {
+        cuckoo_cache.setup(fuzzed_data_provider.ConsumeIntegralInRange<uint32_t>(0, 4096));
+    }
+    while (fuzzed_data_provider.ConsumeBool()) {
+        if (fuzzed_data_provider.ConsumeBool()) {
+            cuckoo_cache.insert(fuzzed_data_provider.ConsumeBool());
+        } else {
+            cuckoo_cache.contains(fuzzed_data_provider.ConsumeBool(), fuzzed_data_provider.ConsumeBool());
+        }
+    }
+    fuzzed_data_provider_ptr = nullptr;
+}