| 1 | package host |
| 2 | |
| 3 | import ( |
| 4 | "os" |
| 5 | "os/exec" |
| 6 | "path/filepath" |
| 7 | "testing" |
| 8 | |
| 9 | "golang.org/x/sys/unix" |
| 10 | ) |
| 11 | |
| 12 | func plan14RootFixture(t *testing.T) bool { |
| 13 | t.Helper() |
| 14 | if os.Getenv("PLAN14_ROOT_FIXTURE") == t.Name() { |
| 15 | root := os.Getenv("PLAN14_ROOT_DIR") |
| 16 | if err := unix.Mount("/proc", filepath.Join(root, "proc"), "", unix.MS_BIND|unix.MS_REC, ""); err != nil { |
| 17 | t.Fatal(err) |
| 18 | } |
| 19 | source := "/usr/bin/true" |
| 20 | if os.Getenv("PLAN14_REAL_ROOT") == "1" { |
| 21 | source = filepath.Join(root, "foreign-source") |
| 22 | } |
| 23 | if err := unix.Mount(source, filepath.Join(root, "foreign"), "", unix.MS_BIND, ""); err != nil { |
| 24 | t.Fatal(err) |
| 25 | } |
| 26 | if err := unix.Mount("/usr", filepath.Join(root, "foreign-dir"), "", unix.MS_BIND, ""); err != nil { |
| 27 | t.Fatal(err) |
| 28 | } |
| 29 | if err := unix.Chroot(root); err != nil { |
| 30 | t.Fatal(err) |
| 31 | } |
| 32 | if err := os.Chdir("/"); err != nil { |
| 33 | t.Fatal(err) |
| 34 | } |
| 35 | if err := os.Chmod("/", 0755); err != nil { |
| 36 | t.Fatal(err) |
| 37 | } |
| 38 | t.Setenv("TMPDIR", "/scratch") |
| 39 | return true |
| 40 | } |
| 41 | root := t.TempDir() |
| 42 | if err := os.Mkdir(filepath.Join(root, "scratch"), 0755); err != nil { |
| 43 | t.Fatal(err) |
| 44 | } |
| 45 | if err := os.Mkdir(filepath.Join(root, "proc"), 0755); err != nil { |
| 46 | t.Fatal(err) |
| 47 | } |
| 48 | if err := os.WriteFile(filepath.Join(root, "foreign"), nil, 0644); err != nil { |
| 49 | t.Fatal(err) |
| 50 | } |
| 51 | if err := os.Mkdir(filepath.Join(root, "foreign-dir"), 0755); err != nil { |
| 52 | t.Fatal(err) |
| 53 | } |
| 54 | binary, err := os.Executable() |
| 55 | if err != nil { |
| 56 | t.Fatal(err) |
| 57 | } |
| 58 | probe := exec.Command("unshare", "--user", "--map-root-user", "--mount", "true") |
| 59 | if out, err := probe.CombinedOutput(); err != nil { |
| 60 | t.Skipf("user namespace unavailable: %v %s", err, out) |
| 61 | } |
| 62 | cmd := exec.Command("unshare", "--user", "--map-root-user", "--mount", binary, "-test.run=^"+t.Name()+"$", "-test.v") |
| 63 | cmd.Env = append(os.Environ(), "PLAN14_ROOT_FIXTURE="+t.Name(), "PLAN14_ROOT_DIR="+root) |
| 64 | if os.Geteuid() == 0 { |
| 65 | raw, err := os.ReadFile("/usr/bin/true") |
| 66 | if err != nil { |
| 67 | t.Fatal(err) |
| 68 | } |
| 69 | source := filepath.Join(root, "foreign-source") |
| 70 | if err := os.WriteFile(source, raw, 0644); err != nil { |
| 71 | t.Fatal(err) |
| 72 | } |
| 73 | if err := os.Chown(source, 65534, 65534); err != nil { |
| 74 | t.Fatal(err) |
| 75 | } |
| 76 | cmd.Env = append(cmd.Env, "PLAN14_REAL_ROOT=1") |
| 77 | } |
| 78 | if out, err := cmd.CombinedOutput(); err != nil { |
| 79 | t.Fatalf("isolated root fixture: %v\n%s", err, out) |
| 80 | } else { |
| 81 | t.Log(string(out)) |
| 82 | } |
| 83 | return false |
| 84 | } |
| 85 | |
| 86 | func makeProofAncestorsPublic(t *testing.T, path string) { |
| 87 | t.Helper() |
| 88 | for dir := filepath.Dir(path); dir != "/"; dir = filepath.Dir(dir) { |
| 89 | if err := os.Chmod(dir, 0755); err != nil { |
| 90 | t.Fatal(err) |
| 91 | } |
| 92 | } |
| 93 | } |
| 94 | |
amadan