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/*
* Copyright 2014 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <stddef.h>
#include <stdint.h>
#include <clocale>
#include <filesystem>
#include <string>
#include "cpp17/generated_cpp17/monster_test_generated.h"
#include "flatbuffers/idl.h"
#include "test_assert.h"
#include "test_init.h"
namespace fs = std::filesystem;
// Utility for test run.
OneTimeTestInit OneTimeTestInit::one_time_init_;
// The current executable path (see LLVMFuzzerInitialize).
static fs::path exe_path_;
static flatbuffers::Parser parser_;
namespace {
static constexpr size_t kMinInputLength = 1;
static constexpr size_t kMaxInputLength = 16384;
static constexpr uint8_t flags_strict_json = 0x80;
static constexpr uint8_t flags_skip_unexpected_fields_in_json = 0x40;
static constexpr uint8_t flags_allow_non_utf8 = 0x20;
bool TestFileExists(fs::path file_path) {
if (file_path.has_filename() && fs::exists(file_path)) return true;
TEST_OUTPUT_LINE("@DEBUG: file '%s' not found", file_path.string().c_str());
for (const auto &entry : fs::directory_iterator(file_path.parent_path())) {
TEST_OUTPUT_LINE("@DEBUG: parent path entry: '%s'",
entry.path().string().c_str());
}
return false;
}
std::string LoadBinarySchema(const char *file_name) {
const auto file_path = exe_path_.parent_path() / file_name;
TEST_EQ(true, TestFileExists(file_path));
std::string schemafile;
TEST_EQ(true,
flatbuffers::LoadFile(file_path.string().c_str(), true, &schemafile));
flatbuffers::Verifier verifier(
reinterpret_cast<const uint8_t *>(schemafile.c_str()), schemafile.size());
TEST_EQ(true, reflection::VerifySchemaBuffer(verifier));
return schemafile;
}
std::string do_test(const flatbuffers::IDLOptions &opts,
const std::string input_json, const bool check_parser) {
// (re)define parser options
parser_.opts = opts;
std::string jsongen;
if (parser_.ParseJson(input_json.c_str())) {
flatbuffers::Verifier verifier(parser_.builder_.GetBufferPointer(),
parser_.builder_.GetSize());
TEST_EQ(true, MyGame::Example::VerifyMonsterBuffer(verifier));
TEST_NULL(
GenText(parser_, parser_.builder_.GetBufferPointer(), &jsongen));
} else if (check_parser) {
TEST_OUTPUT_LINE("parser failed with JSON:\n%s", input_json.c_str());
TEST_EQ_STR("", parser_.error_.c_str());
TEST_ASSERT(false);
}
return jsongen;
};
} // namespace
// https://google.github.io/oss-fuzz/further-reading/fuzzer-environment/
// Current working directory
// You should not make any assumptions about the current working directory of
// your fuzz target. If you need to load data files, please use argv[0] to get
// the directory where your fuzz target executable is located.
// You must not modify argv[0].
extern "C" int LLVMFuzzerInitialize(int *argc, char ***argv) {
(void)argc;
exe_path_ = (*argv)[0];
static const std::string schemafile = LoadBinarySchema("monster_test.bfbs");
// parse schema first, so we can use it to parse the data after
parser_.Deserialize(reinterpret_cast<const uint8_t *>(schemafile.c_str()),
schemafile.size());
return 0;
}
extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
// Reserve one byte for Parser flags and one byte for repetition counter.
if (size < 3) return 0;
const uint8_t flags = data[0];
(void)data[1]; // reserved
data += 2;
size -= 2; // bypass
const std::string original(reinterpret_cast<const char *>(data), size);
auto input = std::string(original.c_str()); // until '\0'
if (input.size() < kMinInputLength || input.size() > kMaxInputLength)
return 0;
flatbuffers::IDLOptions opts;
opts.strict_json = (flags & flags_strict_json);
opts.skip_unexpected_fields_in_json =
(flags & flags_skip_unexpected_fields_in_json);
opts.allow_non_utf8 = (flags & flags_allow_non_utf8);
do {
const std::string jsongen_1 = do_test(opts, input, false);
if (!jsongen_1.empty()) {
const std::string jsongen_2 = do_test(opts, jsongen_1, true);
if (jsongen_1 != jsongen_2 && !opts.output_default_scalars_in_json) {
// This gets tricky when the jsongen_1 includes a default-value, as the
// generated jsongen_2 doesn't emit default-values. So enable default
// scalars and re-run it.
opts.output_default_scalars_in_json = true;
continue;
}
TEST_EQ(jsongen_1, jsongen_2);
}
} while (0);
return 0;
}
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