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

Author: practicalswift

src/Makefile.test.include

@@ -45,6 +45,7 @@ FUZZ_TARGETS = \
   test/fuzz/key_origin_info_deserialize \
   test/fuzz/locale \
   test/fuzz/merkle_block_deserialize \
+  test/fuzz/merkleblock \
   test/fuzz/messageheader_deserialize \
   test/fuzz/multiplication_overflow \
   test/fuzz/net_permissions \
@@ -541,6 +542,12 @@ test_fuzz_merkle_block_deserialize_LDADD = $(FUZZ_SUITE_LD_COMMON)
 test_fuzz_merkle_block_deserialize_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
 test_fuzz_merkle_block_deserialize_SOURCES = $(FUZZ_SUITE) test/fuzz/deserialize.cpp
 
+test_fuzz_merkleblock_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES)
+test_fuzz_merkleblock_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
+test_fuzz_merkleblock_LDADD = $(FUZZ_SUITE_LD_COMMON)
+test_fuzz_merkleblock_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
+test_fuzz_merkleblock_SOURCES = $(FUZZ_SUITE) test/fuzz/merkleblock.cpp
+
 test_fuzz_messageheader_deserialize_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) -DMESSAGEHEADER_DESERIALIZE=1
 test_fuzz_messageheader_deserialize_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS)
 test_fuzz_messageheader_deserialize_LDADD = $(FUZZ_SUITE_LD_COMMON)

src/test/fuzz/merkleblock.cpp

@@ -0,0 +1,27 @@
+// 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 <merkleblock.h>
+#include <optional.h>
+#include <test/fuzz/FuzzedDataProvider.h>
+#include <test/fuzz/fuzz.h>
+#include <test/fuzz/util.h>
+#include <uint256.h>
+
+#include <cstdint>
+#include <string>
+#include <vector>
+
+void test_one_input(const std::vector<uint8_t>& buffer)
+{
+    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
+    Optional<CPartialMerkleTree> partial_merkle_tree = ConsumeDeserializable<CPartialMerkleTree>(fuzzed_data_provider);
+    if (!partial_merkle_tree) {
+        return;
+    }
+    (void)partial_merkle_tree->GetNumTransactions();
+    std::vector<uint256> matches;
+    std::vector<unsigned int> indices;
+    (void)partial_merkle_tree->ExtractMatches(matches, indices);
+}