From b477b1833938da2927b5bbec04766ebd44ac8078 Mon Sep 17 00:00:00 2001
From: AdamKorcz <adam@adalogics.com>
Date: Fri, 1 Oct 2021 13:28:05 +0100
Subject: [PATCH] Fuzzing: Initial commit

Signed-off-by: AdamKorcz <adam@adalogics.com>
---
 fuzz/Dockerfile |  21 +++++++
 fuzz/fuzz.go    | 147 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 168 insertions(+)
 create mode 100644 fuzz/Dockerfile
 create mode 100644 fuzz/fuzz.go

diff --git a/fuzz/Dockerfile b/fuzz/Dockerfile
new file mode 100644
index 000000000..fd08f80db
--- /dev/null
+++ b/fuzz/Dockerfile
@@ -0,0 +1,21 @@
+FROM golang:1.16-buster as builder
+
+RUN apt-get update && apt-get install -y clang git
+RUN git clone --branch fuzz1 --depth 1 https://github.com/AdamKorcz/helm-controller /helm-controller
+COPY fuzz.go /helm-controller/controllers/
+RUN cd /helm-controller/controllers \
+	&& go get github.com/AdaLogics/go-fuzz-headers
+
+RUN cd / \
+	&& go get -u github.com/mdempsky/go114-fuzz-build
+
+RUN mkdir /fuzzers
+RUN cd /helm-controller/controllers \
+	&& go114-fuzz-build -o FuzzHelmreleaseComposeValues.a -func FuzzHelmreleaseComposeValues . \
+	&& clang -o /fuzzers/FuzzHelmreleaseComposeValues FuzzHelmreleaseComposeValues.a -fsanitize=fuzzer
+RUN cd /helm-controller/controllers \
+	&& go114-fuzz-build -o FuzzHelmreleasereconcile.a -func FuzzHelmreleasereconcile . \
+	&& clang -o /fuzzers/FuzzHelmreleasereconcile FuzzHelmreleasereconcile.a -fsanitize=fuzzer
+
+# Uncomment here to run the fuzzer
+#RUN /fuzzers/FuzzHelmreleaseComposeValues
diff --git a/fuzz/fuzz.go b/fuzz/fuzz.go
new file mode 100644
index 000000000..dc3ab5cdb
--- /dev/null
+++ b/fuzz/fuzz.go
@@ -0,0 +1,147 @@
+//go:build gofuzz
+// +build gofuzz
+
+/*
+Copyright 2020 The Flux 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
+    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.
+*/
+package controllers
+
+import (
+	"context"
+	v2 "github.com/fluxcd/helm-controller/api/v2beta1"
+	"github.com/go-logr/logr"
+	corev1 "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"sigs.k8s.io/controller-runtime/pkg/client/fake"
+	"sigs.k8s.io/controller-runtime/pkg/log"
+	"sync"
+
+	fuzz "github.com/AdaLogics/go-fuzz-headers"
+)
+
+var (
+	initter sync.Once
+	scheme  *runtime.Scheme
+)
+
+// An init function that is invoked by way of sync.Do
+func initFunc() {
+	scheme = runtime.NewScheme()
+	err := corev1.AddToScheme(scheme)
+	if err != nil {
+		panic(err)
+	}
+	err = v2.AddToScheme(scheme)
+	if err != nil {
+		panic(err)
+	}
+}
+
+// FuzzHelmreleaseComposeValues implements a fuzzer
+// that targets HelmReleaseReconciler.composeValues()
+func FuzzHelmreleaseComposeValues(data []byte) int {
+	initter.Do(initFunc)
+
+	f := fuzz.NewConsumer(data)
+
+	hr := v2.HelmRelease{}
+	err := f.GenerateStruct(&hr)
+	if err != nil {
+		return 0
+	}
+
+	r, err := createReconciler(f)
+	if err != nil {
+		return 0
+	}
+
+	_, _ = r.composeValues(logr.NewContext(context.TODO(), log.NullLogger{}), hr)
+	return 1
+}
+
+// FuzzHelmreleasereconcile implements a fuzzer
+// that targets HelmReleaseReconciler.reconcile()
+func FuzzHelmreleasereconcile(data []byte) int {
+	initter.Do(initFunc)
+
+	f := fuzz.NewConsumer(data)
+
+	hr := v2.HelmRelease{}
+	err := f.GenerateStruct(&hr)
+	if err != nil {
+		return 0
+	}
+
+	r, err := createReconciler(f)
+	if err != nil {
+		return 0
+	}
+
+	_, _, _ = r.reconcile(logr.NewContext(context.TODO(), log.NullLogger{}), hr)
+	return 1
+}
+
+// Allows the fuzzer to create a reconciler
+func createReconciler(f *fuzz.ConsumeFuzzer) (*HelmReleaseReconciler, error) {
+	// Get the type of object:
+	var resources []runtime.Object
+	r := &HelmReleaseReconciler{}
+	getSecret, err := f.GetBool()
+	if err != nil {
+		return r, err
+	}
+	name, err := f.GetString()
+	if err != nil {
+		return r, err
+	}
+	if getSecret {
+		inputMap := make(map[string][]byte)
+		err = f.FuzzMap(&inputMap)
+		if err != nil {
+			return r, err
+		}
+		resources = []runtime.Object{
+			valuesSecret(name, inputMap),
+		}
+	} else {
+		inputMap := make(map[string]string)
+		err = f.FuzzMap(&inputMap)
+		if err != nil {
+			return r, err
+		}
+		resources = []runtime.Object{
+			valuesConfigMap(name, inputMap),
+		}
+	}
+	c := fake.NewFakeClientWithScheme(scheme, resources...)
+	r.Client = c
+	return r, nil
+}
+
+// Taken from
+// https://github.com/fluxcd/helm-controller/blob/main/controllers/helmrelease_controller_test.go#L282
+func valuesSecret(name string, data map[string][]byte) *corev1.Secret {
+	return &corev1.Secret{
+		ObjectMeta: metav1.ObjectMeta{Name: name},
+		Data:       data,
+	}
+}
+
+// Taken from 
+// https://github.com/fluxcd/helm-controller/blob/main/controllers/helmrelease_controller_test.go#L289
+func valuesConfigMap(name string, data map[string]string) *corev1.ConfigMap {
+	return &corev1.ConfigMap{
+		ObjectMeta: metav1.ObjectMeta{Name: name},
+		Data:       data,
+	}
+}