tests: Add fuzzing harness for V1TransportDeserializer (P2P transport)

1 files changed, 47 insertions, 0 deletions

diff --git a/src/test/fuzz/p2p_transport_deserializer.cpp b/src/test/fuzz/p2p_transport_deserializer.cpp
new file mode 100644
index 0000000000..57393fed45
--- /dev/null
+++ b/src/test/fuzz/p2p_transport_deserializer.cpp
@@ -0,0 +1,47 @@
+// Copyright (c) 2019 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 <chainparams.h>
+#include <net.h>
+#include <protocol.h>
+#include <test/fuzz/fuzz.h>
+
+#include <cassert>
+#include <cstdint>
+#include <limits>
+#include <vector>
+
+void initialize()
+{
+    SelectParams(CBaseChainParams::REGTEST);
+}
+
+void test_one_input(const std::vector<uint8_t>& buffer)
+{
+    V1TransportDeserializer deserializer{Params().MessageStart(), SER_NETWORK, INIT_PROTO_VERSION};
+    const char* pch = (const char*)buffer.data();
+    size_t n_bytes = buffer.size();
+    while (n_bytes > 0) {
+        const int handled = deserializer.Read(pch, n_bytes);
+        if (handled < 0) {
+            break;
+        }
+        pch += handled;
+        n_bytes -= handled;
+        if (deserializer.Complete()) {
+            const int64_t m_time = std::numeric_limits<int64_t>::max();
+            const CNetMessage msg = deserializer.GetMessage(Params().MessageStart(), m_time);
+            assert(msg.m_command.size() <= CMessageHeader::COMMAND_SIZE);
+            assert(msg.m_raw_message_size <= buffer.size());
+            assert(msg.m_raw_message_size == CMessageHeader::HEADER_SIZE + msg.m_message_size);
+            assert(msg.m_time == m_time);
+            if (msg.m_valid_header) {
+                assert(msg.m_valid_netmagic);
+            }
+            if (!msg.m_valid_netmagic) {
+                assert(!msg.m_valid_header);
+            }
+        }
+    }
+}