/*

 * A fuzzer focused on the node::LoadEnvironment() function.

 *

 * Code here has been inspired by the cctest test case.

 */

#include <stdlib.h>

#include "node.h"

#include "node_platform.h"

#include "node_internals.h"

#include "ares_nameser.h"

#include "crypto/crypto_bio.h"

#include "crypto/crypto_context.h"

#include "cares_wrap.h"

#include "env-inl.h"

#include "util-inl.h"

#include "v8.h"

#include "libplatform/libplatform.h"

#include "aliased_buffer.h"

#include "fuzz_helper.h"

using node::AliasedBufferBase;

using v8::Array;

/*int ParseSrvReply(

    node::Environment* env,

    const unsigned char* buf,

    int len,

    v8::Local<Array> ret,

    bool need_type = false);*/

/* General set up */

using ArrayBufferUniquePtr = std::unique_ptr<node::ArrayBufferAllocator,

  decltype(&node::FreeArrayBufferAllocator)>;

using TracingAgentUniquePtr = std::unique_ptr<node::tracing::Agent>;

using NodePlatformUniquePtr = std::unique_ptr<node::NodePlatform>;

static TracingAgentUniquePtr tracing_agent;

static NodePlatformUniquePtr platform;

static uv_loop_t current_loop;

extern "C" int LLVMFuzzerInitialize(int* argc, char*** argv) {

  uv_os_unsetenv("NODE_OPTIONS");

  std::vector<std::string> node_argv{ "fuzz_env" };

  std::vector<std::string> exec_argv;

  std::vector<std::string> errors;

  node::InitializeNodeWithArgs(&node_argv, &exec_argv, &errors);

  tracing_agent = std::make_unique<node::tracing::Agent>();

  node::tracing::TraceEventHelper::SetAgent(tracing_agent.get());

  node::tracing::TracingController* tracing_controller =

    tracing_agent->GetTracingController();  

  CHECK_EQ(0, uv_loop_init(&current_loop));

  static constexpr int kV8ThreadPoolSize = 4;

  platform.reset(

    new node::NodePlatform(kV8ThreadPoolSize, tracing_controller));

  v8::V8::InitializePlatform(platform.get());

  cppgc::InitializeProcess(platform->GetPageAllocator());

  v8::V8::Initialize();

  return 0;

}

class FuzzerFixtureHelper {

public:

  v8::Isolate* isolate_;

  ArrayBufferUniquePtr allocator;

  FuzzerFixtureHelper()

    : allocator(ArrayBufferUniquePtr(node::CreateArrayBufferAllocator(),

                                     &node::FreeArrayBufferAllocator)) {

    isolate_ = NewIsolate(allocator.get(), &current_loop, platform.get());

    CHECK_NOT_NULL(isolate_);

    isolate_->Enter();

  };

  void Teardown() {

    platform->DrainTasks(isolate_);

    isolate_->Exit();

    platform->UnregisterIsolate(isolate_);

    isolate_->Dispose();

    isolate_ = nullptr;

  }

};

void EnvTest(v8::Isolate* isolate_, char* env_string, size_t len) {

  const v8::HandleScope handle_scope(isolate_);

  Argv argv;

  node::EnvironmentFlags::Flags flags = node::EnvironmentFlags::kDefaultFlags;

  auto isolate = handle_scope.GetIsolate();

  v8::Local<v8::Context> context_ = node::NewContext(isolate);

  context_->Enter();

  node::IsolateData* isolate_data_ = node::CreateIsolateData(isolate, &current_loop,

                                                             platform.get());

  std::vector<std::string> args(*argv, *argv + 1);

  std::vector<std::string> exec_args(*argv, *argv + 1);

  node::Environment* environment_ = node::CreateEnvironment(isolate_data_,

                                          context_, args, exec_args, flags);

  node::Environment* envi = environment_;

  SetProcessExitHandler(envi, [&](node::Environment* env_, int exit_code) {

    node::Stop(envi);

  });

  node::LoadEnvironment(envi, "");

  unsigned char* p = reinterpret_cast<unsigned char*>(env_string);

  int type = node::cares_wrap::ns_t_cname_or_a;

  v8::Local<v8::Array> srv_records = Array::New(envi->isolate());

  int status = node::cares_wrap::FuzzParseGeneralReply(envi, p, (int)len, &type, srv_records);

  // Cleanup!

  node::FreeEnvironment(environment_);

  node::FreeIsolateData(isolate_data_);

  context_->Exit();

}

extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data2, size_t size) {

  FuzzerFixtureHelper ffh;

  std::string s(reinterpret_cast<const char*>(data2), size);

  EnvTest(ffh.isolate_, (char*)s.c_str(), size);

  ffh.Teardown();

  return 0;

}