| // Copyright 2019 The Pigweed Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| // use this file except in compliance with the License. You may obtain a copy of |
| // the License at |
| // |
| // https://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| // License for the specific language governing permissions and limitations under |
| // the License. |
| |
| #include <pw_fuzzer/asan_interface.h> |
| #include <pw_fuzzer/fuzzed_data_provider.h> |
| |
| #include <cstddef> |
| #include <cstdint> |
| #include <cstring> |
| #include <span> |
| #include <vector> |
| |
| #include "pw_protobuf/encoder.h" |
| |
| namespace { |
| |
| // Encodable values. The fuzzer will iteratively choose different field types to |
| // generate and encode. |
| enum FieldType : uint8_t { |
| kEncodeAndClear = 0, |
| kUint32, |
| kPackedUint32, |
| kUint64, |
| kPackedUint64, |
| kInt32, |
| kPackedInt32, |
| kInt64, |
| kPackedInt64, |
| kSint32, |
| kPackedSint32, |
| kSint64, |
| kPackedSint64, |
| kBool, |
| kFixed32, |
| kPackedFixed32, |
| kFixed64, |
| kPackedFixed64, |
| kSfixed32, |
| kPackedSfixed32, |
| kSfixed64, |
| kPackedSfixed64, |
| kFloat, |
| kPackedFloat, |
| kDouble, |
| kPackedDouble, |
| kBytes, |
| kString, |
| kPush, |
| kPop, |
| kMaxValue = kPop, |
| }; |
| |
| // TODO(pwbug/181): Move this to pw_fuzzer/fuzzed_data_provider.h |
| |
| // Uses the given |provider| to pick and return a number between 0 and the |
| // maximum numbers of T that can be generated from the remaining input data. |
| template <typename T> |
| size_t ConsumeSize(FuzzedDataProvider* provider) { |
| size_t max = provider->remaining_bytes() / sizeof(T); |
| return provider->ConsumeIntegralInRange<size_t>(0, max); |
| } |
| |
| // Uses the given |provider| to generate several instances of T, store them in |
| // |data|, and then return a std::span to them. It is the caller's responsbility |
| // to ensure |data| remains in scope as long as the returned std::span. |
| template <typename T> |
| std::span<const T> ConsumeSpan(FuzzedDataProvider* provider, |
| std::vector<T>* data) { |
| size_t num = ConsumeSize<T>(provider); |
| size_t off = data->size(); |
| data->reserve(off + num); |
| for (size_t i = 0; i < num; ++i) { |
| if constexpr (std::is_floating_point<T>::value) { |
| data->push_back(provider->ConsumeFloatingPoint<T>()); |
| } else { |
| data->push_back(provider->ConsumeIntegral<T>()); |
| } |
| } |
| return std::span(&((*data)[off]), num); |
| } |
| |
| // Uses the given |provider| to generate a string, store it in |data|, and |
| // return a C-style representation. It is the caller's responsbility to |
| // ensure |data| remains in scope as long as the returned char*. |
| const char* ConsumeString(FuzzedDataProvider* provider, |
| std::vector<std::string>* data) { |
| size_t off = data->size(); |
| // OSS-Fuzz's clang doesn't have the zero-parameter version of |
| // ConsumeRandomLengthString yet. |
| size_t max_length = std::numeric_limits<size_t>::max(); |
| data->push_back(provider->ConsumeRandomLengthString(max_length)); |
| return (*data)[off].c_str(); |
| } |
| |
| // Uses the given |provider| to generate non-arithmetic bytes, store them in |
| // |data|, and return a std::span to them. It is the caller's responsbility to |
| // ensure |data| remains in scope as long as the returned std::span. |
| std::span<const std::byte> ConsumeBytes(FuzzedDataProvider* provider, |
| std::vector<std::byte>* data) { |
| size_t num = ConsumeSize<std::byte>(provider); |
| auto added = provider->ConsumeBytes<std::byte>(num); |
| size_t off = data->size(); |
| num = added.size(); |
| data->insert(data->end(), added.begin(), added.end()); |
| return std::span(&((*data)[off]), num); |
| } |
| |
| } // namespace |
| |
| extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) { |
| static std::byte buffer[65536]; |
| |
| FuzzedDataProvider provider(data, size); |
| |
| // Pick a subset of the buffer that the fuzzer is allowed to use, and poison |
| // the rest. |
| size_t unpoisoned_length = |
| provider.ConsumeIntegralInRange<size_t>(0, sizeof(buffer)); |
| std::span<std::byte> unpoisoned(buffer, unpoisoned_length); |
| void* poisoned = &buffer[unpoisoned_length]; |
| size_t poisoned_length = sizeof(buffer) - unpoisoned_length; |
| ASAN_POISON_MEMORY_REGION(poisoned, poisoned_length); |
| |
| pw::protobuf::NestedEncoder encoder(unpoisoned); |
| std::span<const std::byte> out; |
| |
| // Storage for generated spans |
| std::vector<uint32_t> u32s; |
| std::vector<uint64_t> u64s; |
| std::vector<int32_t> s32s; |
| std::vector<int64_t> s64s; |
| std::vector<float> floats; |
| std::vector<double> doubles; |
| std::vector<std::string> strings; |
| std::vector<std::byte> bytes; |
| |
| // Consume the fuzzing input, using it to generate a sequence of fields to |
| // encode. Both the uint32_t field IDs and the fields values are generated. |
| // Don't try to detect errors, ensures pushes and pops are balanced, or |
| // otherwise hold the interface correctly. Instead, fuzz the widest possbile |
| // set of inputs to the encoder to ensure it doesn't misbehave. |
| while (provider.remaining_bytes() != 0) { |
| switch (provider.ConsumeEnum<FieldType>()) { |
| case kEncodeAndClear: |
| // Special "field". Encode all the fields so far and reset the encoder. |
| encoder.Encode(&out); |
| encoder.Clear(); |
| break; |
| case kUint32: |
| encoder.WriteUint32(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<uint32_t>()); |
| break; |
| case kPackedUint32: |
| encoder.WritePackedUint32(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<uint32_t>(&provider, &u32s)); |
| break; |
| case kUint64: |
| encoder.WriteUint64(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<uint64_t>()); |
| break; |
| case kPackedUint64: |
| encoder.WritePackedUint64(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<uint64_t>(&provider, &u64s)); |
| break; |
| case kInt32: |
| encoder.WriteInt32(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<int32_t>()); |
| break; |
| case kPackedInt32: |
| encoder.WritePackedInt32(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<int32_t>(&provider, &s32s)); |
| break; |
| case kInt64: |
| encoder.WriteInt64(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<int64_t>()); |
| break; |
| case kPackedInt64: |
| encoder.WritePackedInt64(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<int64_t>(&provider, &s64s)); |
| break; |
| case kSint32: |
| encoder.WriteSint32(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<int32_t>()); |
| break; |
| case kPackedSint32: |
| encoder.WritePackedSint32(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<int32_t>(&provider, &s32s)); |
| break; |
| case kSint64: |
| encoder.WriteSint64(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<int64_t>()); |
| break; |
| case kPackedSint64: |
| encoder.WritePackedSint64(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<int64_t>(&provider, &s64s)); |
| break; |
| case kBool: |
| encoder.WriteBool(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeBool()); |
| break; |
| case kFixed32: |
| encoder.WriteFixed32(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<uint32_t>()); |
| break; |
| case kPackedFixed32: |
| encoder.WritePackedFixed32(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<uint32_t>(&provider, &u32s)); |
| break; |
| case kFixed64: |
| encoder.WriteFixed64(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<uint64_t>()); |
| break; |
| case kPackedFixed64: |
| encoder.WritePackedFixed64(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<uint64_t>(&provider, &u64s)); |
| break; |
| case kSfixed32: |
| encoder.WriteSfixed32(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<int32_t>()); |
| break; |
| case kPackedSfixed32: |
| encoder.WritePackedSfixed32(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<int32_t>(&provider, &s32s)); |
| break; |
| case kSfixed64: |
| encoder.WriteSfixed64(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeIntegral<int64_t>()); |
| break; |
| case kPackedSfixed64: |
| encoder.WritePackedSfixed64(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<int64_t>(&provider, &s64s)); |
| break; |
| case kFloat: |
| encoder.WriteFloat(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeFloatingPoint<float>()); |
| break; |
| case kPackedFloat: |
| encoder.WritePackedFloat(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<float>(&provider, &floats)); |
| break; |
| case kDouble: |
| encoder.WriteDouble(provider.ConsumeIntegral<uint32_t>(), |
| provider.ConsumeFloatingPoint<double>()); |
| break; |
| case kPackedDouble: |
| encoder.WritePackedDouble(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeSpan<double>(&provider, &doubles)); |
| break; |
| case kBytes: |
| encoder.WriteBytes(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeBytes(&provider, &bytes)); |
| break; |
| case kString: |
| encoder.WriteString(provider.ConsumeIntegral<uint32_t>(), |
| ConsumeString(&provider, &strings)); |
| break; |
| case kPush: |
| // Special "field". The marks the start of a nested message. |
| encoder.Push(provider.ConsumeIntegral<uint32_t>()); |
| break; |
| case kPop: |
| // Special "field". this marks the end of a nested message. No attempt |
| // is made to match pushes to pops, in order to test that the encoder |
| // behaves correctly when they are mismatched. |
| encoder.Pop(); |
| break; |
| } |
| } |
| // Ensure we call `Encode` at least once. |
| encoder.Encode(&out); |
| |
| // Don't forget to unpoison for the next iteration! |
| ASAN_UNPOISON_MEMORY_REGION(poisoned, poisoned_length); |
| return 0; |
| } |