fuzz_tests: refactor and add OSS-Fuzz compatibility

16 files changed, 234 insertions, 540 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d9ec866e4..14af3b452 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -262,6 +262,12 @@ else()
 endif()
 option(BUILD_DEBUG_UTILITIES "Build debug utilities." DEFAULT_BUILD_DEBUG_UTILITIES)
 
+if(OSSFUZZ)
+  message(STATUS "Using OSS-Fuzz fuzzing system")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DOSSFUZZ")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DOSSFUZZ")
+endif()
+
 # Check whether we're on a 32-bit or 64-bit system
 if(CMAKE_SIZEOF_VOID_P EQUAL "8")
   set(DEFAULT_BUILD_64 ON)
diff --git a/tests/fuzz/CMakeLists.txt b/tests/fuzz/CMakeLists.txt
index a6ef139f5..8654d41d5 100644
--- a/tests/fuzz/CMakeLists.txt
+++ b/tests/fuzz/CMakeLists.txt
@@ -34,7 +34,8 @@ target_link_libraries(block_fuzz_tests
     epee
     device
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET block_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -47,7 +48,8 @@ target_link_libraries(transaction_fuzz_tests
     epee
     device
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET transaction_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -61,7 +63,8 @@ target_link_libraries(signature_fuzz_tests
     epee
     device
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET signature_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -75,7 +78,8 @@ target_link_libraries(cold-outputs_fuzz_tests
     epee
     device
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET cold-outputs_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -89,7 +93,8 @@ target_link_libraries(cold-transaction_fuzz_tests
     epee
     device
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET cold-transaction_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -101,7 +106,8 @@ target_link_libraries(load-from-binary_fuzz_tests
     epee
     ${Boost_PROGRAM_OPTIONS_LIBRARY}
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET load-from-binary_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -113,7 +119,8 @@ target_link_libraries(load-from-json_fuzz_tests
     epee
     ${Boost_PROGRAM_OPTIONS_LIBRARY}
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET load-from-json_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -125,7 +132,8 @@ target_link_libraries(base58_fuzz_tests
     epee
     ${Boost_PROGRAM_OPTIONS_LIBRARY}
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET base58_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -138,7 +146,8 @@ target_link_libraries(parse-url_fuzz_tests
     ${Boost_PROGRAM_OPTIONS_LIBRARY}
     ${Boost_SYSTEM_LIBRARY}
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET parse-url_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -153,7 +162,8 @@ target_link_libraries(http-client_fuzz_tests
     ${Boost_PROGRAM_OPTIONS_LIBRARY}
     ${Boost_SYSTEM_LIBRARY}
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET http-client_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -168,7 +178,8 @@ target_link_libraries(levin_fuzz_tests
     ${Boost_REGEX_LIBRARY}
     ${Boost_PROGRAM_OPTIONS_LIBRARY}
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET levin_fuzz_tests
   PROPERTY
     FOLDER "tests")
@@ -183,7 +194,8 @@ target_link_libraries(bulletproof_fuzz_tests
     ${Boost_REGEX_LIBRARY}
     ${Boost_PROGRAM_OPTIONS_LIBRARY}
     ${CMAKE_THREAD_LIBS_INIT}
-    ${EXTRA_LIBRARIES})
+    ${EXTRA_LIBRARIES}
+    $ENV{LIB_FUZZING_ENGINE})
 set_property(TARGET bulletproof_fuzz_tests
   PROPERTY
     FOLDER "tests")
diff --git a/tests/fuzz/base58.cpp b/tests/fuzz/base58.cpp
index 5f909a5d9..08fa402dd 100644
--- a/tests/fuzz/base58.cpp
+++ b/tests/fuzz/base58.cpp
@@ -27,50 +27,13 @@
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "include_base_utils.h"
-#include "file_io_utils.h"
 #include "common/base58.h"
 #include "fuzzer.h"
 
-class Base58Fuzzer: public Fuzzer
-{
-public:
-  Base58Fuzzer() {}
-  virtual int init();
-  virtual int run(const std::string &filename);
-};
-
-int Base58Fuzzer::init()
-{
-  return 0;
-}
-
-int Base58Fuzzer::run(const std::string &filename)
-{
-  std::string s;
-
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
-  try
-  {
-    std::string data;
-    tools::base58::decode(s, data);
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Failed to load from binary: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  Base58Fuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+BEGIN_INIT_SIMPLE_FUZZER()
+END_INIT_SIMPLE_FUZZER()
 
+BEGIN_SIMPLE_FUZZER()
+  std::string data;
+  tools::base58::decode(std::string((const char*)buf, len), data);
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/block.cpp b/tests/fuzz/block.cpp
index 850c58890..44818f8cd 100644
--- a/tests/fuzz/block.cpp
+++ b/tests/fuzz/block.cpp
@@ -33,36 +33,10 @@
 #include "cryptonote_basic/cryptonote_format_utils.h"
 #include "fuzzer.h"
 
-class BlockFuzzer: public Fuzzer
-{
-public:
-  virtual int run(const std::string &filename);
+BEGIN_INIT_SIMPLE_FUZZER()
+END_INIT_SIMPLE_FUZZER()
 
-private:
-};
-
-int BlockFuzzer::run(const std::string &filename)
-{
-  std::string s;
-
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
+BEGIN_SIMPLE_FUZZER()
   cryptonote::block b = AUTO_VAL_INIT(b);
-  if(!parse_and_validate_block_from_blob(s, b))
-  {
-    std::cout << "Error: failed to parse block from file  " << filename << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  BlockFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+  parse_and_validate_block_from_blob(std::string((const char*)buf, len), b);
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/bulletproof.cpp b/tests/fuzz/bulletproof.cpp
index e9a6ded7d..7e58770ca 100644
--- a/tests/fuzz/bulletproof.cpp
+++ b/tests/fuzz/bulletproof.cpp
@@ -33,40 +33,13 @@
 #include "cryptonote_basic/cryptonote_format_utils.h"
 #include "fuzzer.h"
 
-class BulletproofFuzzer: public Fuzzer
-{
-public:
-  virtual int run(const std::string &filename);
+BEGIN_INIT_SIMPLE_FUZZER()
+END_INIT_SIMPLE_FUZZER()
 
-private:
-};
-
-int BulletproofFuzzer::run(const std::string &filename)
-{
-  std::string s;
-
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
+BEGIN_SIMPLE_FUZZER()
   std::stringstream ss;
-  ss << s;
+  ss << std::string((const char*)buf, len);
   binary_archive<false> ba(ss);
   rct::Bulletproof proof = AUTO_VAL_INIT(proof);
-  bool r = ::serialization::serialize(ba, proof);
-  if(!r)
-  {
-    std::cout << "Error: failed to parse bulletproof from file  " << filename << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  BulletproofFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+  ::serialization::serialize(ba, proof);
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/cold-outputs.cpp b/tests/fuzz/cold-outputs.cpp
index f4050c948..af0a33422 100644
--- a/tests/fuzz/cold-outputs.cpp
+++ b/tests/fuzz/cold-outputs.cpp
@@ -34,70 +34,25 @@
 #include "wallet/wallet2.h"
 #include "fuzzer.h"
 
-class ColdOutputsFuzzer: public Fuzzer
-{
-public:
-  ColdOutputsFuzzer(): wallet(cryptonote::TESTNET) {}
-  virtual int init();
-  virtual int run(const std::string &filename);
+static tools::wallet2 wallet;
 
-private:
-  tools::wallet2 wallet;
-};
-
-int ColdOutputsFuzzer::init()
-{
+BEGIN_INIT_SIMPLE_FUZZER()
   static const char * const spendkey_hex = "0b4f47697ec99c3de6579304e5f25c68b07afbe55b71d99620bf6cbf4e45a80f";
   crypto::secret_key spendkey;
   epee::string_tools::hex_to_pod(spendkey_hex, spendkey);
 
-  try
-  {
-    wallet.init("", boost::none, boost::asio::ip::tcp::endpoint{}, 0, true, epee::net_utils::ssl_support_t::e_ssl_support_disabled);
-    wallet.set_subaddress_lookahead(1, 1);
-    wallet.generate("", "", spendkey, true, false);
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Error on ColdOutputsFuzzer::init: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int ColdOutputsFuzzer::run(const std::string &filename)
-{
-  std::string s;
-
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
-  s = std::string("\x01\x16serialization::archive") + s;
-  try
-  {
-    std::pair<size_t, std::vector<tools::wallet2::transfer_details>> outputs;
-    std::stringstream iss;
-    iss << s;
-    boost::archive::portable_binary_iarchive ar(iss);
-    ar >> outputs;
-    size_t n_outputs = wallet.import_outputs(outputs);
-    std::cout << boost::lexical_cast<std::string>(n_outputs) << " outputs imported" << std::endl;
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Failed to import outputs: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  ColdOutputsFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
-
+  wallet.init("", boost::none, boost::asio::ip::tcp::endpoint{}, 0, true, epee::net_utils::ssl_support_t::e_ssl_support_disabled);
+  wallet.set_subaddress_lookahead(1, 1);
+  wallet.generate("", "", spendkey, true, false);
+END_INIT_SIMPLE_FUZZER()
+
+BEGIN_SIMPLE_FUZZER()
+  std::string s = std::string("\x01\x16serialization::archive") + std::string((const char*)buf, len);
+  std::pair<size_t, std::vector<tools::wallet2::transfer_details>> outputs;
+  std::stringstream iss;
+  iss << s;
+  boost::archive::portable_binary_iarchive ar(iss);
+  ar >> outputs;
+  size_t n_outputs = wallet.import_outputs(outputs);
+  std::cout << boost::lexical_cast<std::string>(n_outputs) << " outputs imported" << std::endl;
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/cold-transaction.cpp b/tests/fuzz/cold-transaction.cpp
index 08117281b..9808362e4 100644
--- a/tests/fuzz/cold-transaction.cpp
+++ b/tests/fuzz/cold-transaction.cpp
@@ -34,71 +34,26 @@
 #include "wallet/wallet2.h"
 #include "fuzzer.h"
 
-class ColdTransactionFuzzer: public Fuzzer
-{
-public:
-  ColdTransactionFuzzer(): wallet(cryptonote::TESTNET) {}
-  virtual int init();
-  virtual int run(const std::string &filename);
+static tools::wallet2 wallet;
 
-private:
-  tools::wallet2 wallet;
-};
-
-
-int ColdTransactionFuzzer::init()
-{
+BEGIN_INIT_SIMPLE_FUZZER()
   static const char * const spendkey_hex = "0b4f47697ec99c3de6579304e5f25c68b07afbe55b71d99620bf6cbf4e45a80f";
   crypto::secret_key spendkey;
   epee::string_tools::hex_to_pod(spendkey_hex, spendkey);
 
-  try
-  {
-    wallet.init("", boost::none, boost::asio::ip::tcp::endpoint{}, 0, true, epee::net_utils::ssl_support_t::e_ssl_support_disabled);
-    wallet.set_subaddress_lookahead(1, 1);
-    wallet.generate("", "", spendkey, true, false);
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Error on ColdTransactionFuzzer::init: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int ColdTransactionFuzzer::run(const std::string &filename)
-{
-  std::string s;
-
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
-  s = std::string("\x01\x16serialization::archive") + s;
-  try
-  {
-    tools::wallet2::unsigned_tx_set exported_txs;
-    std::stringstream iss;
-    iss << s;
-    boost::archive::portable_binary_iarchive ar(iss);
-    ar >> exported_txs;
-    std::vector<tools::wallet2::pending_tx> ptx;
-    bool success = wallet.sign_tx(exported_txs, "/tmp/cold-transaction-test-signed", ptx);
-    std::cout << (success ? "signed" : "error") << std::endl;
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Failed to sign transaction: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  ColdTransactionFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+  wallet.init("", boost::none, boost::asio::ip::tcp::endpoint{}, 0, true, epee::net_utils::ssl_support_t::e_ssl_support_disabled);
+  wallet.set_subaddress_lookahead(1, 1);
+  wallet.generate("", "", spendkey, true, false);
+END_INIT_SIMPLE_FUZZER()
+
+BEGIN_SIMPLE_FUZZER()
+  std::string s = std::string("\x01\x16serialization::archive") + std::string((const char*)buf, len);
+  tools::wallet2::unsigned_tx_set exported_txs;
+  std::stringstream iss;
+  iss << s;
+  boost::archive::portable_binary_iarchive ar(iss);
+  ar >> exported_txs;
+  std::vector<tools::wallet2::pending_tx> ptx;
+  bool success = wallet.sign_tx(exported_txs, "/tmp/cold-transaction-test-signed", ptx);
+  std::cout << (success ? "signed" : "error") << std::endl;
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/fuzzer.cpp b/tests/fuzz/fuzzer.cpp
index 24db5ee05..0d2366263 100644
--- a/tests/fuzz/fuzzer.cpp
+++ b/tests/fuzz/fuzzer.cpp
@@ -33,6 +33,8 @@
 #include "common/util.h"
 #include "fuzzer.h"
 
+#ifndef OSSFUZZ
+
 #if (!defined(__clang__) || (__clang__ < 5))
 static int __AFL_LOOP(int)
 {
@@ -74,3 +76,5 @@ int run_fuzzer(int argc, const char **argv, Fuzzer &fuzzer)
 
   CATCH_ENTRY_L0("run_fuzzer", 1);
 }
+
+#endif
diff --git a/tests/fuzz/fuzzer.h b/tests/fuzz/fuzzer.h
index 5cbd1abc2..2d0a29dfc 100644
--- a/tests/fuzz/fuzzer.h
+++ b/tests/fuzz/fuzzer.h
@@ -27,6 +27,52 @@
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include <string>
+#include "file_io_utils.h"
+
+#ifdef OSSFUZZ
+
+#define BEGIN_INIT_SIMPLE_FUZZER() \
+  static int init() \
+  { \
+    try \
+    {
+
+#define END_INIT_SIMPLE_FUZZER() \
+    } \
+    catch (const std::exception &e) \
+    { \
+      fprintf(stderr, "Exception: %s\n", e.what()); \
+      return 1; \
+    } \
+    return 0; \
+  }
+
+#define BEGIN_SIMPLE_FUZZER() \
+extern "C" { \
+  int LLVMFuzzerTestOneInput(const uint8_t *buf, size_t len) \
+  { \
+    try \
+    { \
+      static bool first = true; \
+      if (first) \
+      { \
+        if (!init()) \
+          return 1; \
+        first = false; \
+      } \
+
+#define END_SIMPLE_FUZZER() \
+    } \
+    catch (const std::exception &e) \
+    { \
+      fprintf(stderr, "Exception: %s\n", e.what()); \
+      return 1; \
+    } \
+    return 0; \
+  } \
+}
+
+#else
 
 class Fuzzer
 {
@@ -36,3 +82,57 @@ public:
 };
 
 int run_fuzzer(int argc, const char **argv, Fuzzer &fuzzer);
+
+#define BEGIN_INIT_SIMPLE_FUZZER() \
+  class SimpleFuzzer: public Fuzzer \
+  { \
+    virtual int init() \
+    { \
+      try \
+      {
+
+#define END_INIT_SIMPLE_FUZZER() \
+      } \
+      catch (const std::exception &e) \
+      { \
+        fprintf(stderr, "Exception: %s\n", e.what()); \
+        return 1; \
+      } \
+      return 0; \
+    }
+
+#define BEGIN_SIMPLE_FUZZER() \
+    virtual int run(const std::string &filename) \
+    { \
+      try \
+      { \
+        std::string s; \
+        if (!epee::file_io_utils::load_file_to_string(filename, s)) \
+        { \
+          std::cout << "Error: failed to load file " << filename << std::endl; \
+          return 1; \
+        } \
+        const uint8_t *buf = (const uint8_t*)s.data(); \
+        const size_t len = s.size(); \
+        {
+
+#define END_SIMPLE_FUZZER() \
+        } \
+      } \
+      catch (const std::exception &e) \
+      { \
+        fprintf(stderr, "Exception: %s\n", e.what()); \
+        return 1; \
+      } \
+      return 0; \
+    } \
+  }; \
+  int main(int argc, const char **argv) \
+  { \
+    TRY_ENTRY(); \
+    SimpleFuzzer fuzzer; \
+    return run_fuzzer(argc, argv, fuzzer); \
+    CATCH_ENTRY_L0("main", 1); \
+  }
+
+#endif
diff --git a/tests/fuzz/http-client.cpp b/tests/fuzz/http-client.cpp
index ea6d5a2ad..1801affee 100644
--- a/tests/fuzz/http-client.cpp
+++ b/tests/fuzz/http-client.cpp
@@ -58,48 +58,11 @@ private:
   std::string data;
 };
 
-class HTTPClientFuzzer: public Fuzzer
-{
-public:
-  HTTPClientFuzzer() {}
-  virtual int init();
-  virtual int run(const std::string &filename);
-
-private:
-  epee::net_utils::http::http_simple_client_template<dummy_client> client;
-};
-
-int HTTPClientFuzzer::init()
-{
-  return 0;
-}
-
-int HTTPClientFuzzer::run(const std::string &filename)
-{
-  std::string s;
+static epee::net_utils::http::http_simple_client_template<dummy_client> client;
 
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
-  try
-  {
-    client.test(s, std::chrono::milliseconds(1000));
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Failed to test http client: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  HTTPClientFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+BEGIN_INIT_SIMPLE_FUZZER()
+END_INIT_SIMPLE_FUZZER()
 
+BEGIN_SIMPLE_FUZZER()
+  client.test(std::string((const char*)buf, len), std::chrono::milliseconds(1000));
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/levin.cpp b/tests/fuzz/levin.cpp
index 6c16a0a85..ab7bbb6da 100644
--- a/tests/fuzz/levin.cpp
+++ b/tests/fuzz/levin.cpp
@@ -279,26 +279,10 @@ namespace
 #endif
 }
 
-class LevinFuzzer: public Fuzzer
-{
-public:
-  LevinFuzzer() {} //: handler(endpoint, config, context) {}
-  virtual int init();
-  virtual int run(const std::string &filename);
-
-private:
-  //epee::net_utils::connection_context_base context;
-  //epee::levin::async_protocol_handler<> handler;
-};
+BEGIN_INIT_SIMPLE_FUZZER()
+END_INIT_SIMPLE_FUZZER()
 
-int LevinFuzzer::init()
-{
-  return 0;
-}
-
-int LevinFuzzer::run(const std::string &filename)
-{
-  std::string s;
+BEGIN_SIMPLE_FUZZER()
 
 #if 0
   epee::levin::bucket_head2 req_head;
@@ -313,13 +297,6 @@ int LevinFuzzer::run(const std::string &filename)
   fwrite(&req_head,sizeof(req_head),1, f);
   fclose(f);
 #endif
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
-  try
-  {
     //std::unique_ptr<test_connection> conn = new test();
     boost::asio::io_service io_service;
     test_levin_protocol_handler_config m_handler_config;
@@ -329,21 +306,5 @@ int LevinFuzzer::run(const std::string &filename)
     conn->start();
     //m_commands_handler.invoke_out_buf(expected_out_data);
     //m_commands_handler.return_code(expected_return_code);
-    conn->m_protocol_handler.handle_recv(s.data(), s.size());
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Failed to test http client: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  LevinFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
-
+    conn->m_protocol_handler.handle_recv(buf, len);
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/load_from_binary.cpp b/tests/fuzz/load_from_binary.cpp
index 85b7361e5..b185df522 100644
--- a/tests/fuzz/load_from_binary.cpp
+++ b/tests/fuzz/load_from_binary.cpp
@@ -33,46 +33,10 @@
 #include "storages/portable_storage_base.h"
 #include "fuzzer.h"
 
-class PortableStorageFuzzer: public Fuzzer
-{
-public:
-  PortableStorageFuzzer() {}
-  virtual int init();
-  virtual int run(const std::string &filename);
-};
-
-int PortableStorageFuzzer::init()
-{
-  return 0;
-}
-
-int PortableStorageFuzzer::run(const std::string &filename)
-{
-  std::string s;
-
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
-  try
-  {
-    epee::serialization::portable_storage ps;
-    ps.load_from_binary(s);
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Failed to load from binary: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  PortableStorageFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+BEGIN_INIT_SIMPLE_FUZZER()
+END_INIT_SIMPLE_FUZZER()
 
+BEGIN_SIMPLE_FUZZER()
+  epee::serialization::portable_storage ps;
+  ps.load_from_binary(std::string((const char*)buf, len));
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/load_from_json.cpp b/tests/fuzz/load_from_json.cpp
index 3ba98050b..0252360ba 100644
--- a/tests/fuzz/load_from_json.cpp
+++ b/tests/fuzz/load_from_json.cpp
@@ -33,46 +33,10 @@
 #include "storages/portable_storage_base.h"
 #include "fuzzer.h"
 
-class PortableStorageFuzzer: public Fuzzer
-{
-public:
-  PortableStorageFuzzer() {}
-  virtual int init();
-  virtual int run(const std::string &filename);
-};
-
-int PortableStorageFuzzer::init()
-{
-  return 0;
-}
-
-int PortableStorageFuzzer::run(const std::string &filename)
-{
-  std::string s;
-
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
-  try
-  {
-    epee::serialization::portable_storage ps;
-    ps.load_from_json(s);
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Failed to load from binary: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  PortableStorageFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+BEGIN_INIT_SIMPLE_FUZZER()
+END_INIT_SIMPLE_FUZZER()
 
+BEGIN_SIMPLE_FUZZER()
+  epee::serialization::portable_storage ps;
+  ps.load_from_json(std::string((const char*)buf, len));
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/parse_url.cpp b/tests/fuzz/parse_url.cpp
index 3db78f9d9..41f4319a6 100644
--- a/tests/fuzz/parse_url.cpp
+++ b/tests/fuzz/parse_url.cpp
@@ -31,46 +31,10 @@
 #include "net/net_parse_helpers.h"
 #include "fuzzer.h"
 
-class ParseURLFuzzer: public Fuzzer
-{
-public:
-  ParseURLFuzzer() {}
-  virtual int init();
-  virtual int run(const std::string &filename);
-};
-
-int ParseURLFuzzer::init()
-{
-  return 0;
-}
-
-int ParseURLFuzzer::run(const std::string &filename)
-{
-  std::string s;
-
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
-  try
-  {
-    epee::net_utils::http::url_content url;
-    epee::net_utils::parse_url(s, url);
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Failed to load from binary: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  ParseURLFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+BEGIN_INIT_SIMPLE_FUZZER()
+END_INIT_SIMPLE_FUZZER()
 
+BEGIN_SIMPLE_FUZZER()
+  epee::net_utils::http::url_content url;
+  epee::net_utils::parse_url(std::string((const char*)buf, len), url);
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/signature.cpp b/tests/fuzz/signature.cpp
index 038378ae2..cd65e42d0 100644
--- a/tests/fuzz/signature.cpp
+++ b/tests/fuzz/signature.cpp
@@ -34,66 +34,28 @@
 #include "wallet/wallet2.h"
 #include "fuzzer.h"
 
-class SignatureFuzzer: public Fuzzer
-{
-public:
-  SignatureFuzzer(): Fuzzer(), wallet(cryptonote::TESTNET) {}
-  virtual int init();
-  virtual int run(const std::string &filename);
+static tools::wallet2 wallet(cryptonote::TESTNET);
+static cryptonote::account_public_address address;
 
-private:
-  tools::wallet2 wallet;
-  cryptonote::account_public_address address;
-};
-
-int SignatureFuzzer::init()
-{
+BEGIN_INIT_SIMPLE_FUZZER()
   static const char * const spendkey_hex = "0b4f47697ec99c3de6579304e5f25c68b07afbe55b71d99620bf6cbf4e45a80f";
   crypto::secret_key spendkey;
   epee::string_tools::hex_to_pod(spendkey_hex, spendkey);
 
-  try
-  {
-    wallet.init("", boost::none, boost::asio::ip::tcp::endpoint{}, 0, true, epee::net_utils::ssl_support_t::e_ssl_support_disabled);
-    wallet.set_subaddress_lookahead(1, 1);
-    wallet.generate("", "", spendkey, true, false);
-
-    cryptonote::address_parse_info info;
-    if (!cryptonote::get_account_address_from_str_or_url(info, cryptonote::TESTNET, "9uVsvEryzpN8WH2t1WWhFFCG5tS8cBNdmJYNRuckLENFimfauV5pZKeS1P2CbxGkSDTUPHXWwiYE5ZGSXDAGbaZgDxobqDN"))
-    {
-      std::cerr << "failed to parse address" << std::endl;
-      return 1;
-    }
-    address = info.address;
-  }
-  catch (const std::exception &e)
-  {
-    std::cerr << "Error on SignatureFuzzer::init: " << e.what() << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int SignatureFuzzer::run(const std::string &filename)
-{
-  std::string s;
+  wallet.init("", boost::none, boost::asio::ip::tcp::endpoint{}, 0, true, epee::net_utils::ssl_support_t::e_ssl_support_disabled);
+  wallet.set_subaddress_lookahead(1, 1);
+  wallet.generate("", "", spendkey, true, false);
 
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
+  cryptonote::address_parse_info info;
+  if (!cryptonote::get_account_address_from_str_or_url(info, cryptonote::TESTNET, "9uVsvEryzpN8WH2t1WWhFFCG5tS8cBNdmJYNRuckLENFimfauV5pZKeS1P2CbxGkSDTUPHXWwiYE5ZGSXDAGbaZgDxobqDN"))
   {
-    std::cout << "Error: failed to load file " << filename << std::endl;
+    std::cerr << "failed to parse address" << std::endl;
     return 1;
   }
+  address = info.address;
+END_INIT_SIMPLE_FUZZER()
 
-  bool valid = wallet.verify("test", address, s);
+BEGIN_SIMPLE_FUZZER()
+  bool valid = wallet.verify("test", address, std::string((const char*)buf, len));
   std::cout << "Signature " << (valid ? "valid" : "invalid") << std::endl;
-
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  SignatureFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+END_SIMPLE_FUZZER()
diff --git a/tests/fuzz/transaction.cpp b/tests/fuzz/transaction.cpp
index 0f62888a1..1e4a61a78 100644
--- a/tests/fuzz/transaction.cpp
+++ b/tests/fuzz/transaction.cpp
@@ -33,36 +33,10 @@
 #include "cryptonote_basic/cryptonote_format_utils.h"
 #include "fuzzer.h"
 
-class TransactionFuzzer: public Fuzzer
-{
-public:
-  virtual int run(const std::string &filename);
+BEGIN_INIT_SIMPLE_FUZZER()
+END_INIT_SIMPLE_FUZZER()
 
-private:
-};
-
-int TransactionFuzzer::run(const std::string &filename)
-{
-  std::string s;
-
-  if (!epee::file_io_utils::load_file_to_string(filename, s))
-  {
-    std::cout << "Error: failed to load file " << filename << std::endl;
-    return 1;
-  }
+BEGIN_SIMPLE_FUZZER()
   cryptonote::transaction tx = AUTO_VAL_INIT(tx);
-  if(!parse_and_validate_tx_from_blob(s, tx))
-  {
-    std::cout << "Error: failed to parse transaction from file  " << filename << std::endl;
-    return 1;
-  }
-  return 0;
-}
-
-int main(int argc, const char **argv)
-{
-  TRY_ENTRY();
-  TransactionFuzzer fuzzer;
-  return run_fuzzer(argc, argv, fuzzer);
-  CATCH_ENTRY_L0("main", 1);
-}
+  parse_and_validate_tx_from_blob(std::string((const char*)buf, len), tx);
+END_SIMPLE_FUZZER()