feat: wrapper creation for libbpf_probe_bpf_helper (#446)

* feat: wrapper creation for libbpf_probe_bpf_helper

* test: test cases for the new wrapper

helpers_test.go

@@ -0,0 +1,59 @@
+package libbpfgo
+
+import (
+	"testing"
+
+	"github.com/aquasecurity/libbpfgo/helpers"
+)
+
+func TestFuncSupportbyType(t *testing.T) {
+	tt := []struct {
+		progType  BPFProgType
+		funcId    helpers.BPFFunc
+		supported bool
+	}{
+		{
+			progType:  BPFProgTypeKprobe,
+			funcId:    helpers.BPFFuncMapLookupElem,
+			supported: true,
+		},
+		{
+			progType:  BPFProgTypeKprobe,
+			funcId:    helpers.BPFFuncLoop,
+			supported: true,
+		},
+		{
+			progType:  BPFProgTypeKprobe,
+			funcId:    helpers.BPFFuncKtimeGetNs,
+			supported: true,
+		},
+		{
+			progType:  BPFProgTypeKprobe,
+			funcId:    helpers.BPFFuncSysBpf,
+			supported: false,
+		},
+		{
+			progType:  BPFProgTypeLsm,
+			funcId:    helpers.BPFFuncGetCurrentCgroupId,
+			supported: false,
+		},
+		{
+			progType:  BPFProgTypeSkLookup,
+			funcId:    helpers.BPFFuncGetCurrentCgroupId,
+			supported: true,
+		},
+		{
+			progType:  BPFProgTypeKprobe,
+			funcId:    helpers.BPFFuncSockMapUpdate,
+			supported: false,
+		},
+	}
+
+	for _, tc := range tt {
+		support, _ := BPFHelperIsSupported(tc.progType, tc.funcId)
+		// This may fail if the bpf helper support for a specific program changes in future.
+		if support != tc.supported {
+			t.Errorf("expected %v, got %v", tc.supported, support)
+		}
+	}
+}

libbpfgo.go

@@ -9,6 +9,8 @@ import "C"
 import (
 	"fmt"
 	"syscall"
+
+	"github.com/aquasecurity/libbpfgo/helpers"
 )
 
 //
@@ -96,6 +98,15 @@ func BPFMapTypeIsSupported(mapType MapType) (bool, error) {
 	return supportedC == 1, nil
 }
 
+func BPFHelperIsSupported(progType BPFProgType, funcId helpers.BPFFunc) (bool, error) {
+	supportedC := C.libbpf_probe_bpf_helper(C.enum_bpf_prog_type(int(progType)), C.enum_bpf_func_id(int(funcId)), nil)
+	if supportedC < 0 {
+		return false, syscall.Errno(-supportedC)
+	}
+
+	return supportedC == 1, nil
+}
+
 //
 // Misc
 //