feat: GetMapsByName

Allow a user to get a list of maps by name.

libbpfgo.go

@@ -393,6 +393,34 @@ func (m *Module) InitGlobalVariable(name string, value interface{}) error {
 	return err
 }
 
+// GetMapsByName retrieves BPF maps with the specified name.
+func GetMapsByName(name string) []*BPFMapLow {
+	bpfMaps := []*BPFMapLow{}
+
+	startId := C.uint(0)
+	nextId := C.uint(0)
+
+	for {
+		err := C.bpf_map_get_next_id(startId, &nextId)
+		if err != 0 {
+			return bpfMaps
+		}
+
+		startId = nextId + 1
+
+		bpfMapLow, errMap := GetMapByID(uint32(nextId))
+		if errMap != nil {
+			return bpfMaps
+		}
+
+		if bpfMapLow.Name() != name {
+			continue
+		}
+
+		bpfMaps = append(bpfMaps, bpfMapLow)
+	}
+}
+
 func (m *Module) GetMap(mapName string) (*BPFMap, error) {
 	cs := C.CString(mapName)
 	bpfMapC, errno := C.bpf_object__find_map_by_name(m.obj, cs)

selftest/map-get-maps-by-name/Makefile

@@ -0,0 +1 @@
+../common/Makefile

selftest/map-get-maps-by-name/go.mod

@@ -0,0 +1,7 @@
+module github.com/aquasecurity/libbpfgo/selftest/map-update
+
+go 1.18
+
+require github.com/aquasecurity/libbpfgo v0.4.7-libbpf-1.2.0-b2e29a1
+
+replace github.com/aquasecurity/libbpfgo => ../../

selftest/map-get-maps-by-name/go.sum

@@ -0,0 +1,4 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ8=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

selftest/map-get-maps-by-name/main.bpf.c

@@ -0,0 +1,20 @@
+//+build ignore
+
+#include <vmlinux.h>
+
+#include <bpf/bpf_helpers.h>
+
+struct {
+    __uint(type, BPF_MAP_TYPE_ARRAY);
+    __uint(max_entries, 1);
+    __uint(key_size, sizeof(u32));
+    __uint(value_size, sizeof(u32));
+} test SEC(".maps");
+
+SEC("kprobe/sys_execve")
+int kprobe__sys_execve(struct pt_regs *ctx)
+{
+    return 0;
+}
+
+char LICENSE[] SEC("license") = "Dual BSD/GPL";

selftest/map-get-maps-by-name/main.go

@@ -0,0 +1,36 @@
+package main
+
+import "C"
+
+import (
+	"fmt"
+	"os"
+	"unsafe"
+
+	bpf "github.com/aquasecurity/libbpfgo"
+)
+
+func main() {
+	bpfModule, err := bpf.NewModuleFromFile("main.bpf.o")
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(-1)
+	}
+	defer bpfModule.Close()
+
+	bpfModule.BPFLoadObject()
+
+	testMaps := bpf.GetMapsByName("test")
+	if len(testMaps) == 0 {
+		fmt.Fprintln(os.Stderr, fmt.Errorf("no maps found"))
+		os.Exit(-1)
+	}
+
+	testMap := testMaps[0]
+	key1 := uint32(0)
+	value1 := uint32(55)
+	if err := testMap.Update(unsafe.Pointer(&key1), unsafe.Pointer(&value1)); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(-1)
+	}
+}

selftest/map-get-maps-by-name/run.sh

@@ -0,0 +1 @@
+../common/run.sh