merge bitcoin#20332: Mock IBD in net_processing fuzzers

src/Makefile.test_util.include

@@ -17,6 +17,7 @@ TEST_UTIL_H = \
     test/util/str.h \
     test/util/transaction_utils.h \
     test/util/wallet.h \
+    test/util/validation.h \
     test/util/xoroshiro128plusplus.h
 
 libtest_util_a_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) $(MINIUPNPC_CPPFLAGS) $(EVENT_CFLAGS) $(EVENT_PTHREADS_CFLAGS)
@@ -30,6 +31,7 @@ libtest_util_a_SOURCES = \
   test/util/setup_common.cpp \
   test/util/str.cpp \
   test/util/transaction_utils.cpp \
+  test/util/validation.cpp \
   test/util/wallet.cpp \
   $(TEST_UTIL_H)
 

src/test/fuzz/process_message.cpp

@@ -17,6 +17,7 @@
 #include <test/util/mining.h>
 #include <test/util/net.h>
 #include <test/util/setup_common.h>
+#include <test/util/validation.h>
 #include <validationinterface.h>
 #include <version.h>
 
@@ -74,10 +75,14 @@ void fuzz_target(FuzzBufferType buffer, const std::string& LIMIT_TO_MESSAGE_TYPE
 {
     FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
     ConnmanTestMsg& connman = *(ConnmanTestMsg*)g_setup->m_node.connman.get();
+    TestChainState& chainstate = *(TestChainState*)&g_setup->m_node.chainman->ActiveChainstate();
+    chainstate.ResetIbd();
     const std::string random_message_type{fuzzed_data_provider.ConsumeBytesAsString(CMessageHeader::COMMAND_SIZE).c_str()};
     if (!LIMIT_TO_MESSAGE_TYPE.empty() && random_message_type != LIMIT_TO_MESSAGE_TYPE) {
         return;
     }
+    const bool jump_out_of_ibd{fuzzed_data_provider.ConsumeBool()};
+    if (jump_out_of_ibd) chainstate.JumpOutOfIbd();
     CNode& p2p_node = *ConsumeNodeAsUniquePtr(fuzzed_data_provider).release();
 
     const bool successfully_connected{fuzzed_data_provider.ConsumeBool()};

src/test/fuzz/process_messages.cpp

@@ -12,6 +12,7 @@
 #include <test/util/mining.h>
 #include <test/util/net.h>
 #include <test/util/setup_common.h>
+#include <test/util/validation.h>
 #include <validation.h>
 #include <validationinterface.h>
 
@@ -34,7 +35,10 @@ FUZZ_TARGET_INIT(process_messages, initialize_process_messages)
     FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
 
     ConnmanTestMsg& connman = *(ConnmanTestMsg*)g_setup->m_node.connman.get();
+    TestChainState& chainstate = *(TestChainState*)&g_setup->m_node.chainman->ActiveChainstate();
+    chainstate.ResetIbd();
     std::vector<CNode*> peers;
+    bool jump_out_of_ibd{false};
 
     const auto num_peers_to_add = fuzzed_data_provider.ConsumeIntegralInRange(1, 3);
     for (int i = 0; i < num_peers_to_add; ++i) {
@@ -51,6 +55,8 @@ FUZZ_TARGET_INIT(process_messages, initialize_process_messages)
     }
 
     while (fuzzed_data_provider.ConsumeBool()) {
+        if (!jump_out_of_ibd) jump_out_of_ibd = fuzzed_data_provider.ConsumeBool();
+        if (jump_out_of_ibd && chainstate.IsInitialBlockDownload()) chainstate.JumpOutOfIbd();
         const std::string random_message_type{fuzzed_data_provider.ConsumeBytesAsString(CMessageHeader::COMMAND_SIZE).c_str()};
 
         CSerializedNetMsg net_msg;

src/test/util/validation.cpp

@@ -0,0 +1,22 @@
+// 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 <test/util/validation.h>
+
+#include <util/check.h>
+#include <util/time.h>
+#include <validation.h>
+
+void TestChainState::ResetIbd()
+{
+    m_cached_finished_ibd = false;
+    assert(IsInitialBlockDownload());
+}
+
+void TestChainState::JumpOutOfIbd()
+{
+    Assert(IsInitialBlockDownload());
+    m_cached_finished_ibd = true;
+    Assert(!IsInitialBlockDownload());
+}

src/test/util/validation.h

@@ -0,0 +1,17 @@
+// 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.
+
+#ifndef BITCOIN_TEST_UTIL_VALIDATION_H
+#define BITCOIN_TEST_UTIL_VALIDATION_H
+
+#include <validation.h>
+
+struct TestChainState : public CChainState {
+    /** Reset the ibd cache to its initial state */
+    void ResetIbd();
+    /** Toggle IsInitialBlockDownload from true to false */
+    void JumpOutOfIbd();
+};
+
+#endif // BITCOIN_TEST_UTIL_VALIDATION_H

src/validation.h

@@ -625,8 +625,7 @@ enum class CoinsCacheSizeState
  */
 class CChainState
 {
-private:
-
+protected:
     /**
      * Every received block is assigned a unique and increasing identifier, so we
      * know which one to give priority in case of a fork.