Merge #18353: tests: Add fuzzing harnesses for classes CBlockHeader, CFeeRate and various functions

44abf417eb1cd8598084eee1a429ca57c7d0579a tests: Add fuzzing harness for various functions taking std::string as input (practicalswift)
d69145acb76ff12b7c5c1e55ce89e14bc6453904 tests: Add fuzzing harness for MultiplicationOverflow(...) (practicalswift)
7726f3bc4671fbc23e5bc31d0eb9fe381e2f07ef tests: Add fuzzing harness for CFeeRate (practicalswift)
0579a276307d22ae62ecbcaa704e8477274e784d tests: Add fuzzing harness for CBlockHeader (practicalswift)
cb4eec13c03089617a94169b4e30381d87788b56 tests: Add fuzzing harness for count_seconds(...) (practicalswift)

Pull request description:

  Add fuzzing harnesses for classes `CBlockHeader`, `CFeeRate` and various functions.

  To test this PR:

  ```
  $ make distclean
  $ ./autogen.sh
  $ CC=clang CXX=clang++ ./configure --enable-fuzz \
        --with-sanitizers=address,fuzzer,undefined
  $ make
  $ src/test/fuzz/block_header
  ^c (ctrl-c)
  $ src/test/fuzz/fee_rate
  ^c (ctrl-c)
  $ src/test/fuzz/integer
  ^c (ctrl-c)
  $ src/test/fuzz/multiplication_overflow
  ^c (ctrl-c)
  $ src/test/fuzz/string
  ^c (ctrl-c)
  ```

ACKs for top commit:
  MarcoFalke:
    ACK 44abf417eb1cd8598084eee1a429ca57c7d0579a 🏉

Tree-SHA512: 2b382a7bc8efdcc6dd8b79f1637f194ecdca3e522c6618ae6c4b0bf6f86d2e79b1bb1c7160522083600616d1ed509b2f577f3a512ea3a7825a0a3794578d9d90

1 files changed, 89 insertions, 0 deletions

diff --git a/src/test/fuzz/string.cpp b/src/test/fuzz/string.cpp
new file mode 100644
index 000000000..bb583885b
--- /dev/null
+++ b/src/test/fuzz/string.cpp
@@ -0,0 +1,89 @@
+// 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 <blockfilter.h>
+#include <clientversion.h>
+#include <logging.h>
+#include <netbase.h>
+#include <outputtype.h>
+#include <rpc/client.h>
+#include <rpc/request.h>
+#include <rpc/server.h>
+#include <rpc/util.h>
+#include <script/descriptor.h>
+#include <test/fuzz/FuzzedDataProvider.h>
+#include <test/fuzz/fuzz.h>
+#include <test/fuzz/util.h>
+#include <util/error.h>
+#include <util/fees.h>
+#include <util/message.h>
+#include <util/settings.h>
+#include <util/strencodings.h>
+#include <util/string.h>
+#include <util/system.h>
+#include <util/translation.h>
+#include <util/url.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());
+    const std::string random_string_1 = fuzzed_data_provider.ConsumeRandomLengthString(32);
+    const std::string random_string_2 = fuzzed_data_provider.ConsumeRandomLengthString(32);
+    const std::vector<std::string> random_string_vector = ConsumeRandomLengthStringVector(fuzzed_data_provider);
+
+    (void)AmountErrMsg(random_string_1, random_string_2);
+    (void)AmountHighWarn(random_string_1);
+    BlockFilterType block_filter_type;
+    (void)BlockFilterTypeByName(random_string_1, block_filter_type);
+    (void)Capitalize(random_string_1);
+    (void)CopyrightHolders(random_string_1);
+    FeeEstimateMode fee_estimate_mode;
+    (void)FeeModeFromString(random_string_1, fee_estimate_mode);
+    (void)FormatParagraph(random_string_1, fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 1000), fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, 1000));
+    (void)FormatSubVersion(random_string_1, fuzzed_data_provider.ConsumeIntegral<int>(), random_string_vector);
+    (void)GetDescriptorChecksum(random_string_1);
+    (void)HelpExampleCli(random_string_1, random_string_2);
+    (void)HelpExampleRpc(random_string_1, random_string_2);
+    (void)HelpMessageGroup(random_string_1);
+    (void)HelpMessageOpt(random_string_1, random_string_2);
+    (void)IsDeprecatedRPCEnabled(random_string_1);
+    (void)Join(random_string_vector, random_string_1);
+    (void)JSONRPCError(fuzzed_data_provider.ConsumeIntegral<int>(), random_string_1);
+    const util::Settings settings;
+    (void)OnlyHasDefaultSectionSetting(settings, random_string_1, random_string_2);
+    (void)ParseNetwork(random_string_1);
+    try {
+        (void)ParseNonRFCJSONValue(random_string_1);
+    } catch (const std::runtime_error&) {
+    }
+    OutputType output_type;
+    (void)ParseOutputType(random_string_1, output_type);
+    (void)ResolveErrMsg(random_string_1, random_string_2);
+    try {
+        (void)RPCConvertNamedValues(random_string_1, random_string_vector);
+    } catch (const std::runtime_error&) {
+    }
+    try {
+        (void)RPCConvertValues(random_string_1, random_string_vector);
+    } catch (const std::runtime_error&) {
+    }
+    (void)SanitizeString(random_string_1);
+    (void)SanitizeString(random_string_1, fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 3));
+    (void)ShellEscape(random_string_1);
+    int port_out;
+    std::string host_out;
+    SplitHostPort(random_string_1, port_out, host_out);
+    (void)TimingResistantEqual(random_string_1, random_string_2);
+    (void)ToLower(random_string_1);
+    (void)ToUpper(random_string_1);
+    (void)TrimString(random_string_1);
+    (void)TrimString(random_string_1, random_string_2);
+    (void)urlDecode(random_string_1);
+    (void)ValidAsCString(random_string_1);
+    (void)_(random_string_1.c_str());
+}