libprotobuf-mutator is a library to randomly mutate protobuffers.
It could be used together with guided fuzzing engines, such as libFuzzer.
Install prerequisites:
sudo apt-get update sudo apt-get install binutils cmake ninja-build
Compile and test everything:
mkdir build cd build cmake ../cmake/ -GNinja -DCMAKE_BUILD_TYPE=Debug ninja check
To use libprotobuf-mutator simply include protobuf_mutator.h and protobuf_mutator.cc into your build files.
The ProtobufMutator class implements mutations of the protobuf tree structure and mutations of individual fields. The field mutation logic is very basic -- for better results you should override the ProtobufMutator::Mutate* methods with more sophisticated logic, e.g. using libFuzzer's mutators.
To apply one mutation to a protobuf object do the following:
class MyProtobufMutator : public ProtobufMutator {
public:
MyProtobufMutator(uint32_t seed) : ProtobufMutator(seed) {}
// Optionally redefine the Mutate* methods to perform more sophisticated mutations.
}
void Mutate(MyMessage* message) {
MyProtobufMutator mutator(my_random_seed);
mutator.Mutate(message, 100, 200);
}
See also the ProtobufMutatorMessagesTest.UsageExample test from protobuf_mutator_test.cc.
TODO