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|
package mount
import (
"os"
"path"
"testing"
"golang.org/x/sys/unix"
)
// nothing is propagated in or out
func TestSubtreePrivate(t *testing.T) {
if os.Getuid() != 0 {
t.Skip("root required")
}
tmp := path.Join(os.TempDir(), "mount-tests")
if err := os.MkdirAll(tmp, 0777); err != nil {
t.Fatal(err)
}
defer os.RemoveAll(tmp)
var (
sourceDir = path.Join(tmp, "source")
targetDir = path.Join(tmp, "target")
outside1Dir = path.Join(tmp, "outside1")
outside2Dir = path.Join(tmp, "outside2")
outside1Path = path.Join(outside1Dir, "file.txt")
outside2Path = path.Join(outside2Dir, "file.txt")
outside1CheckPath = path.Join(targetDir, "a", "file.txt")
outside2CheckPath = path.Join(sourceDir, "b", "file.txt")
)
if err := os.MkdirAll(path.Join(sourceDir, "a"), 0777); err != nil {
t.Fatal(err)
}
if err := os.MkdirAll(path.Join(sourceDir, "b"), 0777); err != nil {
t.Fatal(err)
}
if err := os.Mkdir(targetDir, 0777); err != nil {
t.Fatal(err)
}
if err := os.Mkdir(outside1Dir, 0777); err != nil {
t.Fatal(err)
}
if err := os.Mkdir(outside2Dir, 0777); err != nil {
t.Fatal(err)
}
if err := createFile(outside1Path); err != nil {
t.Fatal(err)
}
if err := createFile(outside2Path); err != nil {
t.Fatal(err)
}
// mount the shared directory to a target
if err := Mount(sourceDir, targetDir, "none", "bind,rw"); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(targetDir); err != nil {
t.Fatal(err)
}
}()
// next, make the target private
if err := MakePrivate(targetDir); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(targetDir); err != nil {
t.Fatal(err)
}
}()
// mount in an outside path to a mounted path inside the _source_
if err := Mount(outside1Dir, path.Join(sourceDir, "a"), "none", "bind,rw"); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(path.Join(sourceDir, "a")); err != nil {
t.Fatal(err)
}
}()
// check that this file _does_not_ show in the _target_
if _, err := os.Stat(outside1CheckPath); err != nil && !os.IsNotExist(err) {
t.Fatal(err)
} else if err == nil {
t.Fatalf("%q should not be visible, but is", outside1CheckPath)
}
// next mount outside2Dir into the _target_
if err := Mount(outside2Dir, path.Join(targetDir, "b"), "none", "bind,rw"); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(path.Join(targetDir, "b")); err != nil {
t.Fatal(err)
}
}()
// check that this file _does_not_ show in the _source_
if _, err := os.Stat(outside2CheckPath); err != nil && !os.IsNotExist(err) {
t.Fatal(err)
} else if err == nil {
t.Fatalf("%q should not be visible, but is", outside2CheckPath)
}
}
// Testing that when a target is a shared mount,
// then child mounts propagate to the source
func TestSubtreeShared(t *testing.T) {
if os.Getuid() != 0 {
t.Skip("root required")
}
tmp := path.Join(os.TempDir(), "mount-tests")
if err := os.MkdirAll(tmp, 0777); err != nil {
t.Fatal(err)
}
defer os.RemoveAll(tmp)
var (
sourceDir = path.Join(tmp, "source")
targetDir = path.Join(tmp, "target")
outsideDir = path.Join(tmp, "outside")
outsidePath = path.Join(outsideDir, "file.txt")
sourceCheckPath = path.Join(sourceDir, "a", "file.txt")
)
if err := os.MkdirAll(path.Join(sourceDir, "a"), 0777); err != nil {
t.Fatal(err)
}
if err := os.Mkdir(targetDir, 0777); err != nil {
t.Fatal(err)
}
if err := os.Mkdir(outsideDir, 0777); err != nil {
t.Fatal(err)
}
if err := createFile(outsidePath); err != nil {
t.Fatal(err)
}
// mount the source as shared
if err := MakeShared(sourceDir); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(sourceDir); err != nil {
t.Fatal(err)
}
}()
// mount the shared directory to a target
if err := Mount(sourceDir, targetDir, "none", "bind,rw"); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(targetDir); err != nil {
t.Fatal(err)
}
}()
// mount in an outside path to a mounted path inside the target
if err := Mount(outsideDir, path.Join(targetDir, "a"), "none", "bind,rw"); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(path.Join(targetDir, "a")); err != nil {
t.Fatal(err)
}
}()
// NOW, check that the file from the outside directory is available in the source directory
if _, err := os.Stat(sourceCheckPath); err != nil {
t.Fatal(err)
}
}
// testing that mounts to a shared source show up in the slave target,
// and that mounts into a slave target do _not_ show up in the shared source
func TestSubtreeSharedSlave(t *testing.T) {
if os.Getuid() != 0 {
t.Skip("root required")
}
tmp := path.Join(os.TempDir(), "mount-tests")
if err := os.MkdirAll(tmp, 0777); err != nil {
t.Fatal(err)
}
defer os.RemoveAll(tmp)
var (
sourceDir = path.Join(tmp, "source")
targetDir = path.Join(tmp, "target")
outside1Dir = path.Join(tmp, "outside1")
outside2Dir = path.Join(tmp, "outside2")
outside1Path = path.Join(outside1Dir, "file.txt")
outside2Path = path.Join(outside2Dir, "file.txt")
outside1CheckPath = path.Join(targetDir, "a", "file.txt")
outside2CheckPath = path.Join(sourceDir, "b", "file.txt")
)
if err := os.MkdirAll(path.Join(sourceDir, "a"), 0777); err != nil {
t.Fatal(err)
}
if err := os.MkdirAll(path.Join(sourceDir, "b"), 0777); err != nil {
t.Fatal(err)
}
if err := os.Mkdir(targetDir, 0777); err != nil {
t.Fatal(err)
}
if err := os.Mkdir(outside1Dir, 0777); err != nil {
t.Fatal(err)
}
if err := os.Mkdir(outside2Dir, 0777); err != nil {
t.Fatal(err)
}
if err := createFile(outside1Path); err != nil {
t.Fatal(err)
}
if err := createFile(outside2Path); err != nil {
t.Fatal(err)
}
// mount the source as shared
if err := MakeShared(sourceDir); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(sourceDir); err != nil {
t.Fatal(err)
}
}()
// mount the shared directory to a target
if err := Mount(sourceDir, targetDir, "none", "bind,rw"); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(targetDir); err != nil {
t.Fatal(err)
}
}()
// next, make the target slave
if err := MakeSlave(targetDir); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(targetDir); err != nil {
t.Fatal(err)
}
}()
// mount in an outside path to a mounted path inside the _source_
if err := Mount(outside1Dir, path.Join(sourceDir, "a"), "none", "bind,rw"); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(path.Join(sourceDir, "a")); err != nil {
t.Fatal(err)
}
}()
// check that this file _does_ show in the _target_
if _, err := os.Stat(outside1CheckPath); err != nil {
t.Fatal(err)
}
// next mount outside2Dir into the _target_
if err := Mount(outside2Dir, path.Join(targetDir, "b"), "none", "bind,rw"); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(path.Join(targetDir, "b")); err != nil {
t.Fatal(err)
}
}()
// check that this file _does_not_ show in the _source_
if _, err := os.Stat(outside2CheckPath); err != nil && !os.IsNotExist(err) {
t.Fatal(err)
} else if err == nil {
t.Fatalf("%q should not be visible, but is", outside2CheckPath)
}
}
func TestSubtreeUnbindable(t *testing.T) {
if os.Getuid() != 0 {
t.Skip("root required")
}
tmp := path.Join(os.TempDir(), "mount-tests")
if err := os.MkdirAll(tmp, 0777); err != nil {
t.Fatal(err)
}
defer os.RemoveAll(tmp)
var (
sourceDir = path.Join(tmp, "source")
targetDir = path.Join(tmp, "target")
)
if err := os.MkdirAll(sourceDir, 0777); err != nil {
t.Fatal(err)
}
if err := os.MkdirAll(targetDir, 0777); err != nil {
t.Fatal(err)
}
// next, make the source unbindable
if err := MakeUnbindable(sourceDir); err != nil {
t.Fatal(err)
}
defer func() {
if err := Unmount(sourceDir); err != nil {
t.Fatal(err)
}
}()
// then attempt to mount it to target. It should fail
if err := Mount(sourceDir, targetDir, "none", "bind,rw"); err != nil && err != unix.EINVAL {
t.Fatal(err)
} else if err == nil {
t.Fatalf("%q should not have been bindable", sourceDir)
}
defer func() {
if err := Unmount(targetDir); err != nil {
t.Fatal(err)
}
}()
}
func createFile(path string) error {
f, err := os.Create(path)
if err != nil {
return err
}
if _, err = f.WriteString("hello world!"); err != nil {
return err
}
return f.Close()
}
|
