| // Copyright 2016 Google Inc. All rights reserved. |
| // |
| // 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 |
| // |
| // http://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. |
| |
| #ifndef SRC_MUTATOR_H_ |
| #define SRC_MUTATOR_H_ |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #include <functional> |
| #include <memory> |
| #include <random> |
| #include <string> |
| #include <unordered_map> |
| #include <vector> |
| |
| #include "port/protobuf.h" |
| #include "src/random.h" |
| |
| namespace protobuf_mutator { |
| |
| // Randomly makes incremental change in the given protobuf. |
| // Usage example: |
| // protobuf_mutator::Mutator mutator(1); |
| // MyMessage message; |
| // message.ParseFromString(encoded_message); |
| // mutator.Mutate(&message, 10000); |
| // |
| // Class implements very basic mutations of fields. E.g. it just flips bits for |
| // integers, floats and strings. Also it increases, decreases size of |
| // strings only by one. For better results users should override |
| // protobuf_mutator::Mutator::Mutate* methods with more useful logic, e.g. using |
| // library like libFuzzer. |
| class Mutator { |
| public: |
| // seed: value to initialize random number generator. |
| Mutator() = default; |
| virtual ~Mutator() = default; |
| |
| // Initialized internal random number generator. |
| void Seed(uint32_t value); |
| |
| // message: message to mutate. |
| // max_size_hint: approximate max ByteSize() of resulting message. Method does |
| // not guarantee that real result will be strictly smaller than value. Caller |
| // could repeat mutation if result was larger than expected. |
| void Mutate(protobuf::Message* message, size_t max_size_hint); |
| |
| void CrossOver(const protobuf::Message& message1, protobuf::Message* message2, |
| size_t max_size_hint); |
| |
| // Makes message initialized and calls post processors to make it valid. |
| void Fix(protobuf::Message* message); |
| |
| // Callback to postprocess mutations. |
| // Implementation should use seed to initialize random number generators. |
| using PostProcess = |
| std::function<void(protobuf::Message* message, unsigned int seed)>; |
| |
| // Register callback which will be called after every message mutation. |
| // In this callback fuzzer may adjust content of the message or mutate some |
| // fields in some fuzzer specific way. |
| void RegisterPostProcessor(const protobuf::Descriptor* desc, |
| PostProcess callback); |
| |
| protected: |
| // TODO(vitalybuka): Consider to replace with single mutate (uint8_t*, size). |
| virtual int32_t MutateInt32(int32_t value); |
| virtual int64_t MutateInt64(int64_t value); |
| virtual uint32_t MutateUInt32(uint32_t value); |
| virtual uint64_t MutateUInt64(uint64_t value); |
| virtual float MutateFloat(float value); |
| virtual double MutateDouble(double value); |
| virtual bool MutateBool(bool value); |
| virtual size_t MutateEnum(size_t index, size_t item_count); |
| virtual std::string MutateString(const std::string& value, |
| int size_increase_hint); |
| |
| RandomEngine* random() { return &random_; } |
| |
| private: |
| friend class FieldMutator; |
| friend class TestMutator; |
| bool MutateImpl(const std::vector<const protobuf::Message*>& sources, |
| const std::vector<protobuf::Message*>& messages, |
| bool copy_clone_only, int size_increase_hint); |
| std::string MutateUtf8String(const std::string& value, |
| int size_increase_hint); |
| bool IsInitialized(const protobuf::Message& message) const; |
| bool keep_initialized_ = true; |
| size_t random_to_default_ratio_ = 100; |
| RandomEngine random_; |
| using PostProcessors = |
| std::unordered_multimap<const protobuf::Descriptor*, PostProcess>; |
| PostProcessors post_processors_; |
| }; |
| |
| } // namespace protobuf_mutator |
| |
| #endif // SRC_MUTATOR_H_ |