| commit | 12a53ca13d6250fa2ced4654636efd781ec4367f | [log] [tgz] |
|---|---|---|
| author | Matt Morehouse <mascasa@google.com> | Wed Aug 02 14:16:26 2017 -0700 |
| committer | Vitaly Buka <vitalybuka@gmail.com> | Wed Aug 02 19:10:33 2017 -0700 |
| tree | b605825b780edd5a9e6f4356e43da7cf7c7d9661 | |
| parent | 2ac9b0f89073743f63a549f2969b7a93056e9f54 [diff] |
Use system-installed protobuf by default. Alternatively, setting DOWNLOAD_PROTOBUF=1 in cmake will have a working protobuf version downloaded and built automatically.
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 liblzma-dev libz-dev docbook2x
Compile and test everything:
mkdir build cd build cmake .. -GNinja -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_BUILD_TYPE=Debug ninja check
Clang is only needed for libFuzzer integration.
By default, the system-installed version of protobuf is used. However, on some systems, the system version is too old. You can pass -DDOWNLOAD_PROTOBUF=1 to cmake to automatically download and build a working version of protobuf.
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 protobuf_mutator::Mutator {
public:
MyProtobufMutator(uint32_t seed) : protobuf_mutator::Mutator(seed) {}
// Optionally redefine the Mutate* methods to perform more sophisticated mutations.
}
void Mutate(MyMessage* message) {
MyProtobufMutator mutator(my_random_seed);
mutator.Mutate(message, 200);
}
See also the ProtobufMutatorMessagesTest.UsageExample test from protobuf_mutator_test.cc.
LibFuzzerProtobufMutator can help to integrate with libFuzzer. For example
#include "src/libfuzzer/libfuzzer_macro.h"
DEFINE_PROTO_FUZZER(const MyMessageType& input) {
// Code which needs to be fuzzed.
ConsumeMyMessageType(input);
}
Please see libfuzzer_example.cc as an example.