Implement changes into volume plugins for skipping chown

Add a separate function for walking directories

pkg/volume/volume_linux_test.go

@@ -0,0 +1,162 @@
+// +build linux
+
+/*
+Copyright 2020 The Kubernetes 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 volume
+
+import (
+	"os"
+	"syscall"
+	"testing"
+
+	v1 "k8s.io/api/core/v1"
+	utiltesting "k8s.io/client-go/util/testing"
+)
+
+type localFakeMounter struct {
+	path       string
+	attributes Attributes
+}
+
+func (l *localFakeMounter) GetPath() string {
+	return l.path
+}
+
+func (l *localFakeMounter) GetAttributes() Attributes {
+	return l.attributes
+}
+
+func (l *localFakeMounter) CanMount() error {
+	return nil
+}
+
+func (l *localFakeMounter) SetUp(mounterArgs MounterArgs) error {
+	return nil
+}
+
+func (l *localFakeMounter) SetUpAt(dir string, mounterArgs MounterArgs) error {
+	return nil
+}
+
+func (l *localFakeMounter) GetMetrics() (*Metrics, error) {
+	return nil, nil
+}
+
+func TestSkipPermissionChange(t *testing.T) {
+	always := v1.AlwaysChangeVolumePermission
+	onrootMismatch := v1.OnRootMismatch
+	tests := []struct {
+		description         string
+		fsGroupChangePolicy *v1.PodFSGroupChangePolicy
+		gidOwnerMatch       bool
+		permissionMatch     bool
+		sgidMatch           bool
+		skipPermssion       bool
+	}{
+		{
+			description:   "skippermission=false, policy=nil",
+			skipPermssion: false,
+		},
+		{
+			description:         "skippermission=false, policy=always",
+			fsGroupChangePolicy: &always,
+			skipPermssion:       false,
+		},
+		{
+			description:         "skippermission=false, policy=onrootmismatch, gidmatch=false",
+			fsGroupChangePolicy: &onrootMismatch,
+			gidOwnerMatch:       false,
+			skipPermssion:       false,
+		},
+		{
+			description:         "skippermission=false, policy=onrootmismatch, gidmatch=true, permmatch=false",
+			fsGroupChangePolicy: &onrootMismatch,
+			gidOwnerMatch:       true,
+			permissionMatch:     false,
+			skipPermssion:       false,
+		},
+		{
+			description:         "skippermission=false, policy=onrootmismatch, gidmatch=true, permmatch=true",
+			fsGroupChangePolicy: &onrootMismatch,
+			gidOwnerMatch:       true,
+			permissionMatch:     true,
+			skipPermssion:       false,
+		},
+		{
+			description:         "skippermission=false, policy=onrootmismatch, gidmatch=true, permmatch=true, sgidmatch=true",
+			fsGroupChangePolicy: &onrootMismatch,
+			gidOwnerMatch:       true,
+			permissionMatch:     true,
+			sgidMatch:           true,
+			skipPermssion:       true,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.description, func(t *testing.T) {
+			tmpDir, err := utiltesting.MkTmpdir("volume_linux_test")
+			if err != nil {
+				t.Fatalf("error creating temp dir: %v", err)
+			}
+
+			defer os.RemoveAll(tmpDir)
+
+			info, err := os.Lstat(tmpDir)
+			if err != nil {
+				t.Fatalf("error reading permission of tmpdir: %v", err)
+			}
+
+			stat, ok := info.Sys().(*syscall.Stat_t)
+			if !ok || stat == nil {
+				t.Fatalf("error reading permission stats for tmpdir: %s", tmpDir)
+			}
+
+			gid := stat.Gid
+
+			var expectedGid int64
+
+			if test.gidOwnerMatch {
+				expectedGid = int64(gid)
+			} else {
+				expectedGid = int64(gid + 3000)
+			}
+
+			mask := rwMask
+
+			if test.sgidMatch {
+				mask |= os.ModeSetgid
+			}
+
+			if test.permissionMatch {
+				mask |= execMask
+
+			}
+			err = os.Chmod(tmpDir, info.Mode()|mask)
+			if err != nil {
+				t.Errorf("Chmod failed on %v: %v", tmpDir, err)
+			}
+
+			mounter := &localFakeMounter{path: tmpDir}
+			ok = skipPermissionChange(mounter, &expectedGid, test.fsGroupChangePolicy)
+			if ok != test.skipPermssion {
+				t.Errorf("for %s expected skipPermission to be %v got %v", test.description, test.skipPermssion, ok)
+			}
+
+		})
+	}
+
+}