1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
|
package nsenter
import (
"bytes"
"encoding/json"
"fmt"
"io"
"io/ioutil"
"os"
"os/exec"
"strings"
"syscall"
"testing"
"github.com/opencontainers/runc/libcontainer"
"github.com/vishvananda/netlink/nl"
)
type pid struct {
Pid int `json:"Pid"`
}
func TestNsenterValidPaths(t *testing.T) {
args := []string{"nsenter-exec"}
parent, child, err := newPipe()
if err != nil {
t.Fatalf("failed to create pipe %v", err)
}
namespaces := []string{
// join pid ns of the current process
fmt.Sprintf("/proc/%d/ns/pid", os.Getpid()),
}
cmd := &exec.Cmd{
Path: os.Args[0],
Args: args,
ExtraFiles: []*os.File{child},
Env: []string{"_LIBCONTAINER_INITPIPE=3"},
Stdout: os.Stdout,
Stderr: os.Stderr,
}
if err := cmd.Start(); err != nil {
t.Fatalf("nsenter failed to start %v", err)
}
// write cloneFlags
r := nl.NewNetlinkRequest(int(libcontainer.InitMsg), 0)
r.AddData(&libcontainer.Int32msg{
Type: libcontainer.CloneFlagsAttr,
Value: uint32(syscall.CLONE_NEWNET),
})
r.AddData(&libcontainer.Bytemsg{
Type: libcontainer.NsPathsAttr,
Value: []byte(strings.Join(namespaces, ",")),
})
if _, err := io.Copy(parent, bytes.NewReader(r.Serialize())); err != nil {
t.Fatal(err)
}
decoder := json.NewDecoder(parent)
var pid *pid
if err := cmd.Wait(); err != nil {
t.Fatalf("nsenter exits with a non-zero exit status")
}
if err := decoder.Decode(&pid); err != nil {
dir, _ := ioutil.ReadDir(fmt.Sprintf("/proc/%d/ns", os.Getpid()))
for _, d := range dir {
t.Log(d.Name())
}
t.Fatalf("%v", err)
}
p, err := os.FindProcess(pid.Pid)
if err != nil {
t.Fatalf("%v", err)
}
p.Wait()
}
func TestNsenterInvalidPaths(t *testing.T) {
args := []string{"nsenter-exec"}
parent, child, err := newPipe()
if err != nil {
t.Fatalf("failed to create pipe %v", err)
}
namespaces := []string{
// join pid ns of the current process
fmt.Sprintf("/proc/%d/ns/pid", -1),
}
cmd := &exec.Cmd{
Path: os.Args[0],
Args: args,
ExtraFiles: []*os.File{child},
Env: []string{"_LIBCONTAINER_INITPIPE=3"},
}
if err := cmd.Start(); err != nil {
t.Fatal(err)
}
// write cloneFlags
r := nl.NewNetlinkRequest(int(libcontainer.InitMsg), 0)
r.AddData(&libcontainer.Int32msg{
Type: libcontainer.CloneFlagsAttr,
Value: uint32(syscall.CLONE_NEWNET),
})
r.AddData(&libcontainer.Bytemsg{
Type: libcontainer.NsPathsAttr,
Value: []byte(strings.Join(namespaces, ",")),
})
if _, err := io.Copy(parent, bytes.NewReader(r.Serialize())); err != nil {
t.Fatal(err)
}
if err := cmd.Wait(); err == nil {
t.Fatalf("nsenter exits with a zero exit status")
}
}
func init() {
if strings.HasPrefix(os.Args[0], "nsenter-") {
os.Exit(0)
}
return
}
func newPipe() (parent *os.File, child *os.File, err error) {
fds, err := syscall.Socketpair(syscall.AF_LOCAL, syscall.SOCK_STREAM|syscall.SOCK_CLOEXEC, 0)
if err != nil {
return nil, nil, err
}
return os.NewFile(uintptr(fds[1]), "parent"), os.NewFile(uintptr(fds[0]), "child"), nil
}
|
