fmt/test/fuzzing/sprintf.cpp
2020-05-07 15:59:46 -07:00

117 lines
2.4 KiB
C++

// Copyright (c) 2019, Paul Dreik
// License: see LICENSE.rst in the fmt root directory
#include <fmt/format.h>
#include <fmt/printf.h>
#include <cstdint>
#include <stdexcept>
#include "fuzzer_common.h"
using fmt_fuzzer::Nfixed;
template <typename Item1, typename Item2>
void invoke_fmt(const uint8_t* Data, size_t Size) {
constexpr auto N1 = sizeof(Item1);
constexpr auto N2 = sizeof(Item2);
static_assert(N1 <= Nfixed, "size1 exceeded");
static_assert(N2 <= Nfixed, "size2 exceeded");
if (Size <= Nfixed + Nfixed) {
return;
}
Item1 item1 = fmt_fuzzer::assignFromBuf<Item1>(Data);
Data += Nfixed;
Size -= Nfixed;
Item2 item2 = fmt_fuzzer::assignFromBuf<Item2>(Data);
Data += Nfixed;
Size -= Nfixed;
auto fmtstring = fmt::string_view(fmt_fuzzer::as_chars(Data), Size);
#if FMT_FUZZ_FORMAT_TO_STRING
std::string message = fmt::format(fmtstring, item1, item2);
#else
fmt::memory_buffer message;
fmt::format_to(message, fmtstring, item1, item2);
#endif
}
// for dynamic dispatching to an explicit instantiation
template <typename Callback> void invoke(int index, Callback callback) {
switch (index) {
case 0:
callback(bool{});
break;
case 1:
callback(char{});
break;
case 2:
using sc = signed char;
callback(sc{});
break;
case 3:
using uc = unsigned char;
callback(uc{});
break;
case 4:
callback(short{});
break;
case 5:
using us = unsigned short;
callback(us{});
break;
case 6:
callback(int{});
break;
case 7:
callback(unsigned{});
break;
case 8:
callback(long{});
break;
case 9:
using ul = unsigned long;
callback(ul{});
break;
case 10:
callback(float{});
break;
case 11:
callback(double{});
break;
case 12:
using LD = long double;
callback(LD{});
break;
case 13:
using ptr = void*;
callback(ptr{});
break;
}
}
extern "C" int LLVMFuzzerTestOneInput(const uint8_t* Data, size_t Size) {
if (Size <= 3) {
return 0;
}
// switch types depending on the first byte of the input
const auto first = Data[0] & 0x0F;
const auto second = (Data[0] & 0xF0) >> 4;
Data++;
Size--;
auto outer = [=](auto param1) {
auto inner = [=](auto param2) {
invoke_fmt<decltype(param1), decltype(param2)>(Data, Size);
};
invoke(second, inner);
};
try {
invoke(first, outer);
} catch (std::exception& /*e*/) {
}
return 0;
}