--- layout: default title: Integrating a Go project parent: Setting up a new project grand_parent: Getting started nav_order: 1 permalink: /getting-started/new-project-guide/go-lang/ --- # Integrating a Go project {: .no_toc} - TOC {:toc} --- The process of integrating a project written in Go with OSS-Fuzz is very similar to the general [Setting up a new project]({{ site.baseurl }}/getting-started/new-project-guide/) process. The key specifics of integrating a Go project are outlined below. ## Go-fuzz support OSS-Fuzz supports **go-fuzz** in the [libFuzzer compatible mode](https://github.com/mdempsky/go114-fuzz-build) only. In that mode, fuzz targets for Go use the libFuzzer engine with native Go coverage instrumentation. Binaries compiled in this mode provide the same libFuzzer command line interface as non-Go fuzz targets. ## Project files First, you need to write a Go fuzz target that accepts a stream of bytes and calls the program API with that. This fuzz target should reside in your project repository ([example](https://github.com/golang/go/blob/4ad13555184eb0697c2e92c64c1b0bdb287ccc10/src/html/fuzz.go#L13)). The structure of the project directory in OSS-Fuzz repository doesn't differ for projects written in Go. The project files have the following Go specific aspects. ### project.yaml The `language` attribute must be specified. ```yaml language: go ``` The only supported fuzzing engine and sanitizer are `libfuzzer` and `address`, respectively. [Example](https://github.com/google/oss-fuzz/blob/356f2b947670b7eb33a1f535c71bc5c87a60b0d1/projects/syzkaller/project.yaml#L7): ```yaml fuzzing_engines: - libfuzzer sanitizers: - address ``` ### Dockerfile The OSS-Fuzz builder image has the latest stable release of Golang installed. In order to install dependencies of your project, add `RUN git clone ...` command to your Dockerfile. [Example](https://github.com/google/oss-fuzz/blob/356f2b947670b7eb33a1f535c71bc5c87a60b0d1/projects/syzkaller/Dockerfile#L23): ```dockerfile # Dependency for one of the fuzz targets. RUN git clone --depth 1 https://github.com/ianlancetaylor/demangle ``` go-fuzz will then automatically download the dependencies based on the go.mod file ### build.sh In order to build a Go fuzz target, you need to call `go-fuzz` command first, and then link the resulting `.a` file against `$LIB_FUZZING_ENGINE` using the `$CXX $CXXFLAGS ...` command. The best way to do this is by using a `compile_go_fuzzer` script, as it also supports coverage builds. A usage example from go-dns project is ```sh compile_go_fuzzer github.com/miekg/dns FuzzNewRR fuzz_newrr fuzz ``` Arguments are : * path of the package with the fuzz target * name of the fuzz function * name of the fuzzer to be built * optional tag to be used by `go build` and such