docker_cli_exec_test.go 18 KB

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  1. // +build !test_no_exec
  2. package main
  3. import (
  4. "bufio"
  5. "fmt"
  6. "net/http"
  7. "os"
  8. "os/exec"
  9. "reflect"
  10. "runtime"
  11. "sort"
  12. "strings"
  13. "sync"
  14. "time"
  15. "github.com/docker/docker/pkg/integration/checker"
  16. icmd "github.com/docker/docker/pkg/integration/cmd"
  17. "github.com/go-check/check"
  18. )
  19. func (s *DockerSuite) TestExec(c *check.C) {
  20. testRequires(c, DaemonIsLinux)
  21. out, _ := dockerCmd(c, "run", "-d", "--name", "testing", "busybox", "sh", "-c", "echo test > /tmp/file && top")
  22. c.Assert(waitRun(strings.TrimSpace(out)), check.IsNil)
  23. out, _ = dockerCmd(c, "exec", "testing", "cat", "/tmp/file")
  24. out = strings.Trim(out, "\r\n")
  25. c.Assert(out, checker.Equals, "test")
  26. }
  27. func (s *DockerSuite) TestExecInteractive(c *check.C) {
  28. testRequires(c, DaemonIsLinux)
  29. dockerCmd(c, "run", "-d", "--name", "testing", "busybox", "sh", "-c", "echo test > /tmp/file && top")
  30. execCmd := exec.Command(dockerBinary, "exec", "-i", "testing", "sh")
  31. stdin, err := execCmd.StdinPipe()
  32. c.Assert(err, checker.IsNil)
  33. stdout, err := execCmd.StdoutPipe()
  34. c.Assert(err, checker.IsNil)
  35. err = execCmd.Start()
  36. c.Assert(err, checker.IsNil)
  37. _, err = stdin.Write([]byte("cat /tmp/file\n"))
  38. c.Assert(err, checker.IsNil)
  39. r := bufio.NewReader(stdout)
  40. line, err := r.ReadString('\n')
  41. c.Assert(err, checker.IsNil)
  42. line = strings.TrimSpace(line)
  43. c.Assert(line, checker.Equals, "test")
  44. err = stdin.Close()
  45. c.Assert(err, checker.IsNil)
  46. errChan := make(chan error)
  47. go func() {
  48. errChan <- execCmd.Wait()
  49. close(errChan)
  50. }()
  51. select {
  52. case err := <-errChan:
  53. c.Assert(err, checker.IsNil)
  54. case <-time.After(1 * time.Second):
  55. c.Fatal("docker exec failed to exit on stdin close")
  56. }
  57. }
  58. func (s *DockerSuite) TestExecAfterContainerRestart(c *check.C) {
  59. testRequires(c, DaemonIsLinux)
  60. out, _ := runSleepingContainer(c)
  61. cleanedContainerID := strings.TrimSpace(out)
  62. c.Assert(waitRun(cleanedContainerID), check.IsNil)
  63. dockerCmd(c, "restart", cleanedContainerID)
  64. c.Assert(waitRun(cleanedContainerID), check.IsNil)
  65. out, _ = dockerCmd(c, "exec", cleanedContainerID, "echo", "hello")
  66. outStr := strings.TrimSpace(out)
  67. c.Assert(outStr, checker.Equals, "hello")
  68. }
  69. func (s *DockerDaemonSuite) TestExecAfterDaemonRestart(c *check.C) {
  70. // TODO Windows CI: Requires a little work to get this ported.
  71. testRequires(c, DaemonIsLinux)
  72. testRequires(c, SameHostDaemon)
  73. err := s.d.StartWithBusybox()
  74. c.Assert(err, checker.IsNil)
  75. out, err := s.d.Cmd("run", "-d", "--name", "top", "-p", "80", "busybox:latest", "top")
  76. c.Assert(err, checker.IsNil, check.Commentf("Could not run top: %s", out))
  77. err = s.d.Restart()
  78. c.Assert(err, checker.IsNil, check.Commentf("Could not restart daemon"))
  79. out, err = s.d.Cmd("start", "top")
  80. c.Assert(err, checker.IsNil, check.Commentf("Could not start top after daemon restart: %s", out))
  81. out, err = s.d.Cmd("exec", "top", "echo", "hello")
  82. c.Assert(err, checker.IsNil, check.Commentf("Could not exec on container top: %s", out))
  83. outStr := strings.TrimSpace(string(out))
  84. c.Assert(outStr, checker.Equals, "hello")
  85. }
  86. // Regression test for #9155, #9044
  87. func (s *DockerSuite) TestExecEnv(c *check.C) {
  88. // TODO Windows CI: This one is interesting and may just end up being a feature
  89. // difference between Windows and Linux. On Windows, the environment is passed
  90. // into the process that is launched, not into the machine environment. Hence
  91. // a subsequent exec will not have LALA set/
  92. testRequires(c, DaemonIsLinux)
  93. runSleepingContainer(c, "-e", "LALA=value1", "-e", "LALA=value2", "-d", "--name", "testing")
  94. c.Assert(waitRun("testing"), check.IsNil)
  95. out, _ := dockerCmd(c, "exec", "testing", "env")
  96. c.Assert(out, checker.Not(checker.Contains), "LALA=value1")
  97. c.Assert(out, checker.Contains, "LALA=value2")
  98. c.Assert(out, checker.Contains, "HOME=/root")
  99. }
  100. func (s *DockerSuite) TestExecExitStatus(c *check.C) {
  101. runSleepingContainer(c, "-d", "--name", "top")
  102. result := icmd.RunCommand(dockerBinary, "exec", "top", "sh", "-c", "exit 23")
  103. c.Assert(result, icmd.Matches, icmd.Expected{ExitCode: 23, Error: "exit status 23"})
  104. }
  105. func (s *DockerSuite) TestExecPausedContainer(c *check.C) {
  106. // Windows does not support pause
  107. testRequires(c, DaemonIsLinux)
  108. defer unpauseAllContainers()
  109. out, _ := dockerCmd(c, "run", "-d", "--name", "testing", "busybox", "top")
  110. ContainerID := strings.TrimSpace(out)
  111. dockerCmd(c, "pause", "testing")
  112. out, _, err := dockerCmdWithError("exec", "-i", "-t", ContainerID, "echo", "hello")
  113. c.Assert(err, checker.NotNil, check.Commentf("container should fail to exec new conmmand if it is paused"))
  114. expected := ContainerID + " is paused, unpause the container before exec"
  115. c.Assert(out, checker.Contains, expected, check.Commentf("container should not exec new command if it is paused"))
  116. }
  117. // regression test for #9476
  118. func (s *DockerSuite) TestExecTTYCloseStdin(c *check.C) {
  119. // TODO Windows CI: This requires some work to port to Windows.
  120. testRequires(c, DaemonIsLinux)
  121. dockerCmd(c, "run", "-d", "-it", "--name", "exec_tty_stdin", "busybox")
  122. cmd := exec.Command(dockerBinary, "exec", "-i", "exec_tty_stdin", "cat")
  123. stdinRw, err := cmd.StdinPipe()
  124. c.Assert(err, checker.IsNil)
  125. stdinRw.Write([]byte("test"))
  126. stdinRw.Close()
  127. out, _, err := runCommandWithOutput(cmd)
  128. c.Assert(err, checker.IsNil, check.Commentf(out))
  129. out, _ = dockerCmd(c, "top", "exec_tty_stdin")
  130. outArr := strings.Split(out, "\n")
  131. c.Assert(len(outArr), checker.LessOrEqualThan, 3, check.Commentf("exec process left running"))
  132. c.Assert(out, checker.Not(checker.Contains), "nsenter-exec")
  133. }
  134. func (s *DockerSuite) TestExecTTYWithoutStdin(c *check.C) {
  135. // TODO Windows CI: This requires some work to port to Windows.
  136. testRequires(c, DaemonIsLinux)
  137. out, _ := dockerCmd(c, "run", "-d", "-ti", "busybox")
  138. id := strings.TrimSpace(out)
  139. c.Assert(waitRun(id), checker.IsNil)
  140. errChan := make(chan error)
  141. go func() {
  142. defer close(errChan)
  143. cmd := exec.Command(dockerBinary, "exec", "-ti", id, "true")
  144. if _, err := cmd.StdinPipe(); err != nil {
  145. errChan <- err
  146. return
  147. }
  148. expected := "the input device is not a TTY"
  149. if runtime.GOOS == "windows" {
  150. expected += ". If you are using mintty, try prefixing the command with 'winpty'"
  151. }
  152. if out, _, err := runCommandWithOutput(cmd); err == nil {
  153. errChan <- fmt.Errorf("exec should have failed")
  154. return
  155. } else if !strings.Contains(out, expected) {
  156. errChan <- fmt.Errorf("exec failed with error %q: expected %q", out, expected)
  157. return
  158. }
  159. }()
  160. select {
  161. case err := <-errChan:
  162. c.Assert(err, check.IsNil)
  163. case <-time.After(3 * time.Second):
  164. c.Fatal("exec is running but should have failed")
  165. }
  166. }
  167. func (s *DockerSuite) TestExecParseError(c *check.C) {
  168. // TODO Windows CI: Requires some extra work. Consider copying the
  169. // runSleepingContainer helper to have an exec version.
  170. testRequires(c, DaemonIsLinux)
  171. dockerCmd(c, "run", "-d", "--name", "top", "busybox", "top")
  172. // Test normal (non-detached) case first
  173. cmd := exec.Command(dockerBinary, "exec", "top")
  174. _, stderr, _, err := runCommandWithStdoutStderr(cmd)
  175. c.Assert(err, checker.NotNil)
  176. c.Assert(stderr, checker.Contains, "See 'docker exec --help'")
  177. }
  178. func (s *DockerSuite) TestExecStopNotHanging(c *check.C) {
  179. // TODO Windows CI: Requires some extra work. Consider copying the
  180. // runSleepingContainer helper to have an exec version.
  181. testRequires(c, DaemonIsLinux)
  182. dockerCmd(c, "run", "-d", "--name", "testing", "busybox", "top")
  183. err := exec.Command(dockerBinary, "exec", "testing", "top").Start()
  184. c.Assert(err, checker.IsNil)
  185. type dstop struct {
  186. out []byte
  187. err error
  188. }
  189. ch := make(chan dstop)
  190. go func() {
  191. out, err := exec.Command(dockerBinary, "stop", "testing").CombinedOutput()
  192. ch <- dstop{out, err}
  193. close(ch)
  194. }()
  195. select {
  196. case <-time.After(3 * time.Second):
  197. c.Fatal("Container stop timed out")
  198. case s := <-ch:
  199. c.Assert(s.err, check.IsNil)
  200. }
  201. }
  202. func (s *DockerSuite) TestExecCgroup(c *check.C) {
  203. // Not applicable on Windows - using Linux specific functionality
  204. testRequires(c, NotUserNamespace)
  205. testRequires(c, DaemonIsLinux)
  206. dockerCmd(c, "run", "-d", "--name", "testing", "busybox", "top")
  207. out, _ := dockerCmd(c, "exec", "testing", "cat", "/proc/1/cgroup")
  208. containerCgroups := sort.StringSlice(strings.Split(out, "\n"))
  209. var wg sync.WaitGroup
  210. var mu sync.Mutex
  211. execCgroups := []sort.StringSlice{}
  212. errChan := make(chan error)
  213. // exec a few times concurrently to get consistent failure
  214. for i := 0; i < 5; i++ {
  215. wg.Add(1)
  216. go func() {
  217. out, _, err := dockerCmdWithError("exec", "testing", "cat", "/proc/self/cgroup")
  218. if err != nil {
  219. errChan <- err
  220. return
  221. }
  222. cg := sort.StringSlice(strings.Split(out, "\n"))
  223. mu.Lock()
  224. execCgroups = append(execCgroups, cg)
  225. mu.Unlock()
  226. wg.Done()
  227. }()
  228. }
  229. wg.Wait()
  230. close(errChan)
  231. for err := range errChan {
  232. c.Assert(err, checker.IsNil)
  233. }
  234. for _, cg := range execCgroups {
  235. if !reflect.DeepEqual(cg, containerCgroups) {
  236. fmt.Println("exec cgroups:")
  237. for _, name := range cg {
  238. fmt.Printf(" %s\n", name)
  239. }
  240. fmt.Println("container cgroups:")
  241. for _, name := range containerCgroups {
  242. fmt.Printf(" %s\n", name)
  243. }
  244. c.Fatal("cgroups mismatched")
  245. }
  246. }
  247. }
  248. func (s *DockerSuite) TestExecInspectID(c *check.C) {
  249. out, _ := runSleepingContainer(c, "-d")
  250. id := strings.TrimSuffix(out, "\n")
  251. out = inspectField(c, id, "ExecIDs")
  252. c.Assert(out, checker.Equals, "[]", check.Commentf("ExecIDs should be empty, got: %s", out))
  253. // Start an exec, have it block waiting so we can do some checking
  254. cmd := exec.Command(dockerBinary, "exec", id, "sh", "-c",
  255. "while ! test -e /execid1; do sleep 1; done")
  256. err := cmd.Start()
  257. c.Assert(err, checker.IsNil, check.Commentf("failed to start the exec cmd"))
  258. // Give the exec 10 chances/seconds to start then give up and stop the test
  259. tries := 10
  260. for i := 0; i < tries; i++ {
  261. // Since its still running we should see exec as part of the container
  262. out = strings.TrimSpace(inspectField(c, id, "ExecIDs"))
  263. if out != "[]" && out != "<no value>" {
  264. break
  265. }
  266. c.Assert(i+1, checker.Not(checker.Equals), tries, check.Commentf("ExecIDs still empty after 10 second"))
  267. time.Sleep(1 * time.Second)
  268. }
  269. // Save execID for later
  270. execID, err := inspectFilter(id, "index .ExecIDs 0")
  271. c.Assert(err, checker.IsNil, check.Commentf("failed to get the exec id"))
  272. // End the exec by creating the missing file
  273. err = exec.Command(dockerBinary, "exec", id,
  274. "sh", "-c", "touch /execid1").Run()
  275. c.Assert(err, checker.IsNil, check.Commentf("failed to run the 2nd exec cmd"))
  276. // Wait for 1st exec to complete
  277. cmd.Wait()
  278. // Give the exec 10 chances/seconds to stop then give up and stop the test
  279. for i := 0; i < tries; i++ {
  280. // Since its still running we should see exec as part of the container
  281. out = strings.TrimSpace(inspectField(c, id, "ExecIDs"))
  282. if out == "[]" {
  283. break
  284. }
  285. c.Assert(i+1, checker.Not(checker.Equals), tries, check.Commentf("ExecIDs still not empty after 10 second"))
  286. time.Sleep(1 * time.Second)
  287. }
  288. // But we should still be able to query the execID
  289. sc, body, err := sockRequest("GET", "/exec/"+execID+"/json", nil)
  290. c.Assert(sc, checker.Equals, http.StatusOK, check.Commentf("received status != 200 OK: %d\n%s", sc, body))
  291. // Now delete the container and then an 'inspect' on the exec should
  292. // result in a 404 (not 'container not running')
  293. out, ec := dockerCmd(c, "rm", "-f", id)
  294. c.Assert(ec, checker.Equals, 0, check.Commentf("error removing container: %s", out))
  295. sc, body, err = sockRequest("GET", "/exec/"+execID+"/json", nil)
  296. c.Assert(sc, checker.Equals, http.StatusNotFound, check.Commentf("received status != 404: %d\n%s", sc, body))
  297. }
  298. func (s *DockerSuite) TestLinksPingLinkedContainersOnRename(c *check.C) {
  299. // Problematic on Windows as Windows does not support links
  300. testRequires(c, DaemonIsLinux)
  301. var out string
  302. out, _ = dockerCmd(c, "run", "-d", "--name", "container1", "busybox", "top")
  303. idA := strings.TrimSpace(out)
  304. c.Assert(idA, checker.Not(checker.Equals), "", check.Commentf("%s, id should not be nil", out))
  305. out, _ = dockerCmd(c, "run", "-d", "--link", "container1:alias1", "--name", "container2", "busybox", "top")
  306. idB := strings.TrimSpace(out)
  307. c.Assert(idB, checker.Not(checker.Equals), "", check.Commentf("%s, id should not be nil", out))
  308. dockerCmd(c, "exec", "container2", "ping", "-c", "1", "alias1", "-W", "1")
  309. dockerCmd(c, "rename", "container1", "container_new")
  310. dockerCmd(c, "exec", "container2", "ping", "-c", "1", "alias1", "-W", "1")
  311. }
  312. func (s *DockerSuite) TestRunMutableNetworkFiles(c *check.C) {
  313. // Not applicable on Windows to Windows CI.
  314. testRequires(c, SameHostDaemon, DaemonIsLinux)
  315. for _, fn := range []string{"resolv.conf", "hosts"} {
  316. deleteAllContainers()
  317. content, err := runCommandAndReadContainerFile(fn, exec.Command(dockerBinary, "run", "-d", "--name", "c1", "busybox", "sh", "-c", fmt.Sprintf("echo success >/etc/%s && top", fn)))
  318. c.Assert(err, checker.IsNil)
  319. c.Assert(strings.TrimSpace(string(content)), checker.Equals, "success", check.Commentf("Content was not what was modified in the container", string(content)))
  320. out, _ := dockerCmd(c, "run", "-d", "--name", "c2", "busybox", "top")
  321. contID := strings.TrimSpace(out)
  322. netFilePath := containerStorageFile(contID, fn)
  323. f, err := os.OpenFile(netFilePath, os.O_WRONLY|os.O_SYNC|os.O_APPEND, 0644)
  324. c.Assert(err, checker.IsNil)
  325. if _, err := f.Seek(0, 0); err != nil {
  326. f.Close()
  327. c.Fatal(err)
  328. }
  329. if err := f.Truncate(0); err != nil {
  330. f.Close()
  331. c.Fatal(err)
  332. }
  333. if _, err := f.Write([]byte("success2\n")); err != nil {
  334. f.Close()
  335. c.Fatal(err)
  336. }
  337. f.Close()
  338. res, _ := dockerCmd(c, "exec", contID, "cat", "/etc/"+fn)
  339. c.Assert(res, checker.Equals, "success2\n")
  340. }
  341. }
  342. func (s *DockerSuite) TestExecWithUser(c *check.C) {
  343. // TODO Windows CI: This may be fixable in the future once Windows
  344. // supports users
  345. testRequires(c, DaemonIsLinux)
  346. dockerCmd(c, "run", "-d", "--name", "parent", "busybox", "top")
  347. out, _ := dockerCmd(c, "exec", "-u", "1", "parent", "id")
  348. c.Assert(out, checker.Contains, "uid=1(daemon) gid=1(daemon)")
  349. out, _ = dockerCmd(c, "exec", "-u", "root", "parent", "id")
  350. c.Assert(out, checker.Contains, "uid=0(root) gid=0(root)", check.Commentf("exec with user by id expected daemon user got %s", out))
  351. }
  352. func (s *DockerSuite) TestExecWithPrivileged(c *check.C) {
  353. // Not applicable on Windows
  354. testRequires(c, DaemonIsLinux, NotUserNamespace)
  355. // Start main loop which attempts mknod repeatedly
  356. dockerCmd(c, "run", "-d", "--name", "parent", "--cap-drop=ALL", "busybox", "sh", "-c", `while (true); do if [ -e /exec_priv ]; then cat /exec_priv && mknod /tmp/sda b 8 0 && echo "Success"; else echo "Privileged exec has not run yet"; fi; usleep 10000; done`)
  357. // Check exec mknod doesn't work
  358. cmd := exec.Command(dockerBinary, "exec", "parent", "sh", "-c", "mknod /tmp/sdb b 8 16")
  359. out, _, err := runCommandWithOutput(cmd)
  360. c.Assert(err, checker.NotNil, check.Commentf("exec mknod in --cap-drop=ALL container without --privileged should fail"))
  361. c.Assert(out, checker.Contains, "Operation not permitted", check.Commentf("exec mknod in --cap-drop=ALL container without --privileged should fail"))
  362. // Check exec mknod does work with --privileged
  363. cmd = exec.Command(dockerBinary, "exec", "--privileged", "parent", "sh", "-c", `echo "Running exec --privileged" > /exec_priv && mknod /tmp/sdb b 8 16 && usleep 50000 && echo "Finished exec --privileged" > /exec_priv && echo ok`)
  364. out, _, err = runCommandWithOutput(cmd)
  365. c.Assert(err, checker.IsNil)
  366. actual := strings.TrimSpace(out)
  367. c.Assert(actual, checker.Equals, "ok", check.Commentf("exec mknod in --cap-drop=ALL container with --privileged failed, output: %q", out))
  368. // Check subsequent unprivileged exec cannot mknod
  369. cmd = exec.Command(dockerBinary, "exec", "parent", "sh", "-c", "mknod /tmp/sdc b 8 32")
  370. out, _, err = runCommandWithOutput(cmd)
  371. c.Assert(err, checker.NotNil, check.Commentf("repeating exec mknod in --cap-drop=ALL container after --privileged without --privileged should fail"))
  372. c.Assert(out, checker.Contains, "Operation not permitted", check.Commentf("repeating exec mknod in --cap-drop=ALL container after --privileged without --privileged should fail"))
  373. // Confirm at no point was mknod allowed
  374. logCmd := exec.Command(dockerBinary, "logs", "parent")
  375. out, _, err = runCommandWithOutput(logCmd)
  376. c.Assert(err, checker.IsNil)
  377. c.Assert(out, checker.Not(checker.Contains), "Success")
  378. }
  379. func (s *DockerSuite) TestExecWithImageUser(c *check.C) {
  380. // Not applicable on Windows
  381. testRequires(c, DaemonIsLinux)
  382. name := "testbuilduser"
  383. _, err := buildImage(name,
  384. `FROM busybox
  385. RUN echo 'dockerio:x:1001:1001::/bin:/bin/false' >> /etc/passwd
  386. USER dockerio`,
  387. true)
  388. c.Assert(err, checker.IsNil)
  389. dockerCmd(c, "run", "-d", "--name", "dockerioexec", name, "top")
  390. out, _ := dockerCmd(c, "exec", "dockerioexec", "whoami")
  391. c.Assert(out, checker.Contains, "dockerio", check.Commentf("exec with user by id expected dockerio user got %s", out))
  392. }
  393. func (s *DockerSuite) TestExecOnReadonlyContainer(c *check.C) {
  394. // Windows does not support read-only
  395. // --read-only + userns has remount issues
  396. testRequires(c, DaemonIsLinux, NotUserNamespace)
  397. dockerCmd(c, "run", "-d", "--read-only", "--name", "parent", "busybox", "top")
  398. dockerCmd(c, "exec", "parent", "true")
  399. }
  400. func (s *DockerSuite) TestExecUlimits(c *check.C) {
  401. testRequires(c, DaemonIsLinux)
  402. name := "testexeculimits"
  403. runSleepingContainer(c, "-d", "--ulimit", "nproc=21", "--name", name)
  404. c.Assert(waitRun(name), checker.IsNil)
  405. out, _, err := dockerCmdWithError("exec", name, "sh", "-c", "ulimit -p")
  406. c.Assert(err, checker.IsNil)
  407. c.Assert(strings.TrimSpace(out), checker.Equals, "21")
  408. }
  409. // #15750
  410. func (s *DockerSuite) TestExecStartFails(c *check.C) {
  411. // TODO Windows CI. This test should be portable. Figure out why it fails
  412. // currently.
  413. testRequires(c, DaemonIsLinux)
  414. name := "exec-15750"
  415. runSleepingContainer(c, "-d", "--name", name)
  416. c.Assert(waitRun(name), checker.IsNil)
  417. out, _, err := dockerCmdWithError("exec", name, "no-such-cmd")
  418. c.Assert(err, checker.NotNil, check.Commentf(out))
  419. c.Assert(out, checker.Contains, "executable file not found")
  420. }