udp listener fuzzer (#15974)

* test: common: network: add udp listener fuzzer.

Signed-off-by: davkor <[email protected]>

test/common/network/BUILD

@@ -393,6 +393,30 @@ envoy_cc_test(
     ],
 )
 
+envoy_cc_fuzz_test(
+    name = "udp_fuzz",
+    srcs = ["udp_fuzz.cc"],
+    corpus = "udp_corpus",
+    deps = [
+        "udp_listener_impl_test_base_lib",
+        "//source/common/event:dispatcher_lib",
+        "//source/common/network:address_lib",
+        "//source/common/network:listener_lib",
+        "//source/common/network:socket_option_lib",
+        "//source/common/network:udp_packet_writer_handler_lib",
+        "//source/common/network:utility_lib",
+        "//source/common/stats:stats_lib",
+        "//test/common/network:listener_impl_test_base_lib",
+        "//test/mocks/network:network_mocks",
+        "//test/mocks/server:server_mocks",
+        "//test/test_common:environment_lib",
+        "//test/test_common:network_utility_lib",
+        "//test/test_common:threadsafe_singleton_injector_lib",
+        "//test/test_common:utility_lib",
+        "@envoy_api//envoy/config/core/v3:pkg_cc_proto",
+    ],
+)
+
 envoy_cc_fuzz_test(
     name = "utility_fuzz_test",
     srcs = ["utility_fuzz_test.cc"],

test/common/network/udp_fuzz.cc

@@ -0,0 +1,183 @@
+#include <fuzzer/FuzzedDataProvider.h>
+
+#include "envoy/config/core/v3/base.pb.h"
+
+#include "common/api/os_sys_calls_impl.h"
+#include "common/network/address_impl.h"
+#include "common/network/socket_option_factory.h"
+#include "common/network/socket_option_impl.h"
+#include "common/network/udp_listener_impl.h"
+#include "common/network/udp_packet_writer_handler_impl.h"
+#include "common/network/utility.h"
+
+#include "test/common/network/udp_listener_impl_test_base.h"
+#include "test/fuzz/fuzz_runner.h"
+#include "test/mocks/api/mocks.h"
+#include "test/mocks/network/mocks.h"
+#include "test/mocks/server/mocks.h"
+#include "test/test_common/environment.h"
+#include "test/test_common/network_utility.h"
+#include "test/test_common/threadsafe_singleton_injector.h"
+#include "test/test_common/utility.h"
+
+namespace Envoy {
+namespace {
+
+class OverrideOsSysCallsImpl : public Api::OsSysCallsImpl {
+public:
+  MOCK_METHOD(bool, supportsUdpGro, (), (const));
+  MOCK_METHOD(bool, supportsMmsg, (), (const));
+};
+
+class UdpFuzz;
+
+class FuzzUdpListenerCallbacks : public Network::UdpListenerCallbacks {
+public:
+  FuzzUdpListenerCallbacks(UdpFuzz* upf) : my_upf_(upf) {}
+  ~FuzzUdpListenerCallbacks() override = default;
+  void onData(Network::UdpRecvData&& data) override;
+  void onReadReady() override;
+  void onWriteReady(const Network::Socket& socket) override;
+  void onReceiveError(Api::IoError::IoErrorCode error_code) override;
+  void onDataWorker(Network::UdpRecvData&& data) override;
+  void post(Network::UdpRecvData&& data) override;
+  void onDatagramsDropped(uint32_t dropped) override;
+  uint32_t workerIndex() const override;
+  Network::UdpPacketWriter& udpPacketWriter() override;
+
+private:
+  UdpFuzz* my_upf_;
+};
+
+class UdpFuzz {
+public:
+  UdpFuzz(const uint8_t* buf, size_t len) {
+    // Prepare environment
+    api_ = Api::createApiForTest();
+    dispatcher_ = api_->allocateDispatcher("test_thread");
+    ip_version_ = TestEnvironment::getIpVersionsForTest()[0];
+
+    server_socket_ = createServerSocket(true, ip_version_);
+    server_socket_->addOptions(Network::SocketOptionFactory::buildIpPacketInfoOptions());
+    server_socket_->addOptions(Network::SocketOptionFactory::buildRxQueueOverFlowOptions());
+
+    // Create packet writer
+    udp_packet_writer_ = std::make_unique<Network::UdpDefaultWriter>(server_socket_->ioHandle());
+
+    // Set up callbacks
+    FuzzUdpListenerCallbacks fuzzCallbacks(this);
+
+    // Create listener with default config
+    envoy::config::core::v3::UdpSocketConfig config;
+
+    FuzzedDataProvider provider(buf, len);
+    uint16_t SocketType = provider.ConsumeIntegralInRange<uint16_t>(0, 2);
+    if (SocketType == 0) {
+      config.mutable_prefer_gro()->set_value(true);
+      ON_CALL(override_syscall_, supportsUdpGro()).WillByDefault(Return(true));
+    } else if (SocketType == 1) {
+      ON_CALL(override_syscall_, supportsMmsg()).WillByDefault(Return(true));
+    } else {
+      ON_CALL(override_syscall_, supportsMmsg()).WillByDefault(Return(false));
+      ON_CALL(override_syscall_, supportsUdpGro()).WillByDefault(Return(false));
+    }
+
+    std::unique_ptr<Network::UdpListenerImpl> listener_ =
+        std::make_unique<Network::UdpListenerImpl>(dispatcherImpl(), server_socket_, fuzzCallbacks,
+                                                   dispatcherImpl().timeSource(), config);
+
+    Network::Address::Instance* send_to_addr_ = new Network::Address::Ipv4Instance(
+        "127.0.0.1", server_socket_->addressProvider().localAddress()->ip()->port());
+
+    // Now do all of the fuzzing
+    static const int MaxPackets = 15;
+    total_packets_ = provider.ConsumeIntegralInRange<uint16_t>(1, MaxPackets);
+    Network::Test::UdpSyncPeer client_(ip_version_);
+    for (uint16_t i = 0; i < total_packets_; i++) {
+      std::string packet_ =
+          provider.ConsumeBytesAsString(provider.ConsumeIntegralInRange<uint32_t>(1, 3000));
+      if (packet_.empty()) {
+        packet_ = "EMPTY_PACKET";
+      }
+      client_.write(packet_, *send_to_addr_);
+    }
+    dispatcher_->run(Event::Dispatcher::RunType::Block);
+
+    // cleanup
+    delete send_to_addr_;
+  }
+
+  Event::DispatcherImpl& dispatcherImpl() {
+    // We need access to the concrete impl type in order to instantiate a
+    // Test[Udp]Listener, which instantiates a [Udp]ListenerImpl, which requires
+    // a DispatcherImpl to access DispatcherImpl::base_, which is not part of
+    // the Dispatcher API.
+    Event::DispatcherImpl* impl = dynamic_cast<Event::DispatcherImpl*>(dispatcher_.get());
+    return *impl;
+  }
+
+  Network::SocketSharedPtr createServerSocket(bool bind, Network::Address::IpVersion version) {
+    // Set IP_FREEBIND to allow sendmsg to send with non-local IPv6 source
+    // address.
+    return std::make_shared<Network::UdpListenSocket>(
+        Network::Test::getCanonicalLoopbackAddress(version),
+#ifdef IP_FREEBIND
+        Network::SocketOptionFactory::buildIpFreebindOptions(),
+#else
+        nullptr,
+#endif
+        bind);
+  }
+
+  Network::SocketSharedPtr server_socket_;
+  Event::DispatcherPtr dispatcher_;
+  Api::ApiPtr api_;
+  Network::UdpPacketWriterPtr udp_packet_writer_;
+  uint16_t sent_packets_ = 0;
+  uint16_t total_packets_;
+  Network::Address::IpVersion ip_version_;
+  NiceMock<OverrideOsSysCallsImpl> override_syscall_;
+  TestThreadsafeSingletonInjector<Api::OsSysCallsImpl> os_calls{&override_syscall_};
+};
+
+void FuzzUdpListenerCallbacks::onData(Network::UdpRecvData&& data) {
+  my_upf_->sent_packets_++;
+  if (my_upf_->sent_packets_ == my_upf_->total_packets_) {
+    my_upf_->dispatcher_->exit();
+  }
+  UNREFERENCED_PARAMETER(data);
+}
+
+void FuzzUdpListenerCallbacks::onReadReady() {}
+
+void FuzzUdpListenerCallbacks::onWriteReady(const Network::Socket& socket) {
+  UNREFERENCED_PARAMETER(socket);
+}
+
+void FuzzUdpListenerCallbacks::onReceiveError(Api::IoError::IoErrorCode error_code) {
+  my_upf_->sent_packets_++;
+  if (my_upf_->sent_packets_ == my_upf_->total_packets_) {
+    my_upf_->dispatcher_->exit();
+  }
+  UNREFERENCED_PARAMETER(error_code);
+}
+Network::UdpPacketWriter& FuzzUdpListenerCallbacks::udpPacketWriter() {
+  return *my_upf_->udp_packet_writer_;
+}
+uint32_t FuzzUdpListenerCallbacks::workerIndex() const { return 0; }
+void FuzzUdpListenerCallbacks::onDataWorker(Network::UdpRecvData&& data) {
+  UNREFERENCED_PARAMETER(data);
+}
+void FuzzUdpListenerCallbacks::post(Network::UdpRecvData&& data) { UNREFERENCED_PARAMETER(data); }
+
+void FuzzUdpListenerCallbacks::onDatagramsDropped(uint32_t dropped) {
+  my_upf_->sent_packets_++;
+  if (my_upf_->sent_packets_ == my_upf_->total_packets_) {
+    my_upf_->dispatcher_->exit();
+  }
+  UNREFERENCED_PARAMETER(dropped);
+}
+
+DEFINE_FUZZER(const uint8_t* buf, size_t len) { UdpFuzz udp_instance(buf, len); }
+} // namespace
+} // namespace Envoy