containerd/pkg/sys/namespace_linux_test.go
Wei Fu fd3f3d5a13 pkg/sys: add GetUsernsForNamespace interface
Signed-off-by: Wei Fu <fuweid89@gmail.com>
2024-09-11 07:21:43 +08:00

107 lines
2.7 KiB
Go

/*
Copyright The containerd 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 sys
import (
"fmt"
"os"
"syscall"
"testing"
kernel "github.com/containerd/containerd/v2/pkg/kernelversion"
"github.com/containerd/continuity/testutil"
"github.com/stretchr/testify/require"
"golang.org/x/sys/unix"
)
func TestGetUsernsForNamespace(t *testing.T) {
testutil.RequiresRoot(t)
t.Parallel()
k409 := kernel.KernelVersion{Kernel: 4, Major: 9}
ok, err := kernel.GreaterEqualThan(k409)
require.NoError(t, err)
if !ok {
t.Skip("Requires kernel >= 4.9")
}
tmpDir := t.TempDir()
f, err := os.CreateTemp(tmpDir, "netns")
require.NoError(t, err)
netnsPath := f.Name()
f.Close()
defer testutil.Unmount(t, netnsPath)
currentUsernsIno, err := getNamespaceInode(os.Getpid(), "user")
require.NoError(t, err)
usernsIno := uint64(0)
uerr := UnshareAfterEnterUserns("0:1000:10", "0:1000:10", syscall.CLONE_NEWNET, func(pid int) error {
err := unix.Mount(
fmt.Sprintf("/proc/%d/ns/net", pid),
netnsPath,
"",
unix.MS_BIND|unix.MS_RDONLY,
"",
)
if err != nil {
return err
}
usernsIno, err = getNamespaceInode(pid, "user")
if err != nil {
return err
}
return nil
})
require.NoError(t, uerr)
require.NotEqual(t, currentUsernsIno, usernsIno)
t.Logf("Current user namespace [%d], new user namespace [%d]", currentUsernsIno, usernsIno)
netnsFd, err := os.Open(netnsPath)
require.NoError(t, err)
defer netnsFd.Close()
usernsFd, err := GetUsernsForNamespace(netnsFd.Fd())
require.NoError(t, err)
defer usernsFd.Close()
usernsInoFromNetnsFd := getInode(t, usernsFd)
t.Logf("Fetch netns namespace %s' user namespace owner %d", netnsPath, usernsInoFromNetnsFd)
require.Equal(t, usernsIno, usernsInoFromNetnsFd)
parentUsernsFd, err := GetUsernsForNamespace(usernsFd.Fd())
require.NoError(t, err)
defer parentUsernsFd.Close()
parentUsernsIno := getInode(t, parentUsernsFd)
t.Logf("User namespace %d's parent %d", usernsInoFromNetnsFd, parentUsernsIno)
require.Equal(t, currentUsernsIno, parentUsernsIno)
}
func getInode(t *testing.T, f *os.File) uint64 {
info, err := f.Stat()
require.NoError(t, err)
return info.Sys().(*syscall.Stat_t).Ino
}