fuzzing: run latest fuzzers in OSS-Fuzz

This PR adds multiple fuzzers to Ciliums OSS-Fuzz build script.
OSS-Fuzz will build the fuzzers and run them continuously.

Ciliums OSS-Fuzz integration can be found here: https://github.com/google/oss-fuzz/tree/master/projects/cilium - the build script will invoke Ciliums upstream OSS-Fuzz build script

Signed-off-by: AdamKorcz <adam@adalogics.com>

test/fuzzing/oss-fuzz-build.sh

@@ -1,3 +1,23 @@
 #/bin/bash -eu
 
+# The oss-fuzz-build.sh is meant to only be run inside the OSS-Fuzz build environment.
+# In that environment, the fuzzers are built with go build which does not include _test.go files
+# in its scope and they are therefore renamed.
+# When run locally by developers with go test -fuzz then the renaming is not necessary.
+# Ciliums OSS-Fuzz integration can be found here: https://github.com/google/oss-fuzz/tree/master/projects/cilium
+
+
+# Add a fuzz dependency because OSS-Fuzz rewrites the testing types to ones compatible with libFuzzer which is the fuzzing engine used by OSS-Fuzz:
+printf "package policy\nimport _ \"github.com/AdamKorcz/go-118-fuzz-build/testing\"\n" > $SRC/cilium/pkg/policy/registerfuzzdep.go
+
+go mod tidy && go mod vendor
+mv $SRC/cilium/pkg/policy/l4_filter_test.go $SRC/cilium/pkg/policy/l4_filter_test_fuzz.go
+mv $SRC/cilium/pkg/policy/policy_test.go $SRC/cilium/pkg/policy/policy_test_fuzz.go
+mv $SRC/cilium/pkg/policy/rule_test.go $SRC/cilium/pkg/policy/rule_test_fuzz.go
+mv $SRC/cilium/pkg/policy/selectorcache_test.go $SRC/cilium/pkg/policy/selectorcache_test_fuzz.go
+
 compile_go_fuzzer github.com/cilium/cilium/test/fuzzing Fuzz fuzz gofuzz
+compile_native_go_fuzzer github.com/cilium/cilium/pkg/monitor/format FuzzFormatEvent FuzzFormatEvent
+compile_native_go_fuzzer github.com/cilium/cilium/pkg/k8s/apis/cilium.io/v2 FuzzCiliumNetworkPolicyParse FuzzCiliumNetworkPolicyParse
+compile_native_go_fuzzer github.com/cilium/cilium/pkg/k8s/apis/cilium.io/v2 FuzzCiliumClusterwideNetworkPolicyParse FuzzCiliumClusterwideNetworkPolicyParse
+compile_native_go_fuzzer github.com/cilium/cilium/pkg/policy FuzzTest FuzzResolveEgressPolicy