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			129 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			129 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
// Copyright (c) 2019, Paul Dreik
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// License: see LICENSE.rst in the fmt root directory
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#include <fmt/chrono.h>
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#include <fmt/core.h>
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#include <cstdint>
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#include <stdexcept>
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#include <type_traits>
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#include <vector>
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#include "fuzzer_common.h"
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template <typename Item1>
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void invoke_fmt(const uint8_t* Data, std::size_t Size, unsigned int argsize) {
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  constexpr auto N1 = sizeof(Item1);
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  static_assert(N1 <= fmt_fuzzer::Nfixed, "Nfixed too small");
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  if (Size <= fmt_fuzzer::Nfixed) {
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    return;
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  }
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  const Item1 item1 = fmt_fuzzer::assignFromBuf<Item1>(Data);
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  Data += fmt_fuzzer::Nfixed;
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  Size -= fmt_fuzzer::Nfixed;
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  // how many chars should be used for the argument name?
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  if (argsize <= 0 || argsize >= Size) {
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    return;
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  }
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  // allocating buffers separately is slower, but increases chances
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  // of detecting memory errors
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#if FMT_FUZZ_SEPARATE_ALLOCATION
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  std::vector<char> argnamebuffer(argsize);
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  std::memcpy(argnamebuffer.data(), Data, argsize);
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  auto argname = fmt::string_view(argnamebuffer.data(), argsize);
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#else
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  auto argname = fmt::string_view(fmt_fuzzer::as_chars(Data), argsize);
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#endif
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  Data += argsize;
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  Size -= argsize;
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#if FMT_FUZZ_SEPARATE_ALLOCATION
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  // allocates as tight as possible, making it easier to catch buffer overruns.
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  std::vector<char> fmtstringbuffer(Size);
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  std::memcpy(fmtstringbuffer.data(), Data, Size);
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  auto fmtstring = fmt::string_view(fmtstringbuffer.data(), Size);
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#else
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  auto fmtstring = fmt::string_view(fmt_fuzzer::as_chars(Data), Size);
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#endif
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#if FMT_FUZZ_FORMAT_TO_STRING
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  std::string message = fmt::format(fmtstring, fmt::arg(argname, item1));
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#else
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  fmt::memory_buffer outbuf;
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  fmt::format_to(outbuf, fmtstring, fmt::arg(argname, item1));
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#endif
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}
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// for dynamic dispatching to an explicit instantiation
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template <typename Callback> void invoke(int index, Callback callback) {
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  switch (index) {
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  case 0:
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    callback(bool{});
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    break;
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  case 1:
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    callback(char{});
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    break;
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  case 2:
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    using sc = signed char;
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    callback(sc{});
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    break;
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  case 3:
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    using uc = unsigned char;
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    callback(uc{});
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    break;
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  case 4:
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    callback(short{});
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    break;
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  case 5:
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    using us = unsigned short;
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    callback(us{});
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    break;
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  case 6:
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    callback(int{});
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    break;
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  case 7:
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    callback(unsigned{});
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    break;
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  case 8:
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    callback(long{});
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    break;
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  case 9:
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    using ul = unsigned long;
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    callback(ul{});
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    break;
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  case 10:
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    callback(float{});
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    break;
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  case 11:
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    callback(double{});
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    break;
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  case 12:
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    using LD = long double;
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    callback(LD{});
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    break;
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  }
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}
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extern "C" int LLVMFuzzerTestOneInput(const uint8_t* Data, std::size_t Size) {
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  if (Size <= 3) {
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    return 0;
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  }
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  // switch types depending on the first byte of the input
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  const auto first = Data[0] & 0x0F;
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  const unsigned int second = (Data[0] & 0xF0) >> 4;
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  Data++;
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  Size--;
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  auto outerfcn = [=](auto param1) {
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    invoke_fmt<decltype(param1)>(Data, Size, second);
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  };
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  try {
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    invoke(first, outerfcn);
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  } catch (std::exception& /*e*/) {
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  }
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  return 0;
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}
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