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Diffstat (limited to 'libpod/oci_linux.go')
-rw-r--r--libpod/oci_linux.go414
1 files changed, 125 insertions, 289 deletions
diff --git a/libpod/oci_linux.go b/libpod/oci_linux.go
index 9ce836cb5..45365203e 100644
--- a/libpod/oci_linux.go
+++ b/libpod/oci_linux.go
@@ -3,78 +3,29 @@
package libpod
import (
- "bufio"
- "bytes"
"fmt"
- "io/ioutil"
"os"
"os/exec"
"path/filepath"
"runtime"
- "strconv"
"strings"
"syscall"
"time"
"github.com/containers/libpod/libpod/define"
- "github.com/containers/libpod/pkg/cgroups"
"github.com/containers/libpod/pkg/errorhandling"
"github.com/containers/libpod/pkg/rootless"
"github.com/containers/libpod/pkg/util"
"github.com/containers/libpod/utils"
pmount "github.com/containers/storage/pkg/mount"
- "github.com/coreos/go-systemd/activation"
- spec "github.com/opencontainers/runtime-spec/specs-go"
- "github.com/opencontainers/selinux/go-selinux"
- "github.com/opencontainers/selinux/go-selinux/label"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
"golang.org/x/sys/unix"
+ "k8s.io/client-go/tools/remotecommand"
)
const unknownPackage = "Unknown"
-func (r *OCIRuntime) moveConmonToCgroup(ctr *Container, cgroupParent string, cmd *exec.Cmd) error {
- if os.Geteuid() == 0 {
- if r.cgroupManager == SystemdCgroupsManager {
- unitName := createUnitName("libpod-conmon", ctr.ID())
-
- realCgroupParent := cgroupParent
- splitParent := strings.Split(cgroupParent, "/")
- if strings.HasSuffix(cgroupParent, ".slice") && len(splitParent) > 1 {
- realCgroupParent = splitParent[len(splitParent)-1]
- }
-
- logrus.Infof("Running conmon under slice %s and unitName %s", realCgroupParent, unitName)
- if err := utils.RunUnderSystemdScope(cmd.Process.Pid, realCgroupParent, unitName); err != nil {
- logrus.Warnf("Failed to add conmon to systemd sandbox cgroup: %v", err)
- }
- } else {
- cgroupPath := filepath.Join(ctr.config.CgroupParent, "conmon")
- control, err := cgroups.New(cgroupPath, &spec.LinuxResources{})
- if err != nil {
- logrus.Warnf("Failed to add conmon to cgroupfs sandbox cgroup: %v", err)
- } else {
- // we need to remove this defer and delete the cgroup once conmon exits
- // maybe need a conmon monitor?
- if err := control.AddPid(cmd.Process.Pid); err != nil {
- logrus.Warnf("Failed to add conmon to cgroupfs sandbox cgroup: %v", err)
- }
- }
- }
- }
- return nil
-}
-
-// newPipe creates a unix socket pair for communication
-func newPipe() (parent *os.File, child *os.File, err error) {
- fds, err := unix.Socketpair(unix.AF_LOCAL, unix.SOCK_STREAM|unix.SOCK_CLOEXEC, 0)
- if err != nil {
- return nil, nil, err
- }
- return os.NewFile(uintptr(fds[1]), "parent"), os.NewFile(uintptr(fds[0]), "child"), nil
-}
-
// makeAccessible changes the path permission and each parent directory to have --x--x--x
func makeAccessible(path string, uid, gid int) error {
for ; path != "/"; path = filepath.Dir(path) {
@@ -100,7 +51,7 @@ func makeAccessible(path string, uid, gid int) error {
// CreateContainer creates a container in the OCI runtime
// TODO terminal support for container
// Presently just ignoring conmon opts related to it
-func (r *OCIRuntime) createContainer(ctr *Container, cgroupParent string, restoreOptions *ContainerCheckpointOptions) (err error) {
+func (r *OCIRuntime) createContainer(ctr *Container, restoreOptions *ContainerCheckpointOptions) (err error) {
if len(ctr.config.IDMappings.UIDMap) != 0 || len(ctr.config.IDMappings.GIDMap) != 0 {
for _, i := range []string{ctr.state.RunDir, ctr.runtime.config.TmpDir, ctr.config.StaticDir, ctr.state.Mountpoint, ctr.runtime.config.VolumePath} {
if err := makeAccessible(i, ctr.RootUID(), ctr.RootGID()); err != nil {
@@ -152,7 +103,7 @@ func (r *OCIRuntime) createContainer(ctr *Container, cgroupParent string, restor
return errors.Wrapf(err, "cannot unmount %s", m.Mountpoint)
}
}
- return r.createOCIContainer(ctr, cgroupParent, restoreOptions)
+ return r.createOCIContainer(ctr, restoreOptions)
}()
ch <- err
}()
@@ -160,7 +111,7 @@ func (r *OCIRuntime) createContainer(ctr *Container, cgroupParent string, restor
return err
}
}
- return r.createOCIContainer(ctr, cgroupParent, restoreOptions)
+ return r.createOCIContainer(ctr, restoreOptions)
}
func rpmVersion(path string) string {
@@ -195,293 +146,178 @@ func (r *OCIRuntime) conmonPackage() string {
return dpkgVersion(r.conmonPath)
}
-func (r *OCIRuntime) createOCIContainer(ctr *Container, cgroupParent string, restoreOptions *ContainerCheckpointOptions) (err error) {
- var stderrBuf bytes.Buffer
+// execContainer executes a command in a running container
+// TODO: Add --detach support
+// TODO: Convert to use conmon
+// TODO: add --pid-file and use that to generate exec session tracking
+func (r *OCIRuntime) execContainer(c *Container, cmd, capAdd, env []string, tty bool, cwd, user, sessionID string, streams *AttachStreams, preserveFDs int, resize chan remotecommand.TerminalSize, detachKeys string) (int, chan error, error) {
+ if len(cmd) == 0 {
+ return -1, nil, errors.Wrapf(define.ErrInvalidArg, "must provide a command to execute")
+ }
- runtimeDir, err := util.GetRootlessRuntimeDir()
- if err != nil {
- return err
+ if sessionID == "" {
+ return -1, nil, errors.Wrapf(define.ErrEmptyID, "must provide a session ID for exec")
}
- parentPipe, childPipe, err := newPipe()
+ // create sync pipe to receive the pid
+ parentSyncPipe, childSyncPipe, err := newPipe()
if err != nil {
- return errors.Wrapf(err, "error creating socket pair")
+ return -1, nil, errors.Wrapf(err, "error creating socket pair")
}
+ defer errorhandling.CloseQuiet(parentSyncPipe)
+
+ // create start pipe to set the cgroup before running
+ // attachToExec is responsible for closing parentStartPipe
childStartPipe, parentStartPipe, err := newPipe()
if err != nil {
- return errors.Wrapf(err, "error creating socket pair for start pipe")
+ return -1, nil, errors.Wrapf(err, "error creating socket pair")
}
- defer errorhandling.CloseQuiet(parentPipe)
- defer errorhandling.CloseQuiet(parentStartPipe)
+ // We want to make sure we close the parent{Start,Attach}Pipes if we fail
+ // but also don't want to close them after attach to exec is called
+ attachToExecCalled := false
- ociLog := filepath.Join(ctr.state.RunDir, "oci-log")
- logLevel := logrus.GetLevel()
+ defer func() {
+ if !attachToExecCalled {
+ errorhandling.CloseQuiet(parentStartPipe)
+ }
+ }()
- args := []string{}
- if r.cgroupManager == SystemdCgroupsManager {
- args = append(args, "-s")
- }
- args = append(args, "-c", ctr.ID())
- args = append(args, "-u", ctr.ID())
- args = append(args, "-n", ctr.Name())
- args = append(args, "-r", r.path)
- args = append(args, "-b", ctr.bundlePath())
- args = append(args, "-p", filepath.Join(ctr.state.RunDir, "pidfile"))
- args = append(args, "--exit-dir", r.exitsDir)
- if logLevel != logrus.DebugLevel && r.supportsJSON {
- args = append(args, "--runtime-arg", "--log-format=json", "--runtime-arg", "--log", fmt.Sprintf("--runtime-arg=%s", ociLog))
- }
- if ctr.config.ConmonPidFile != "" {
- args = append(args, "--conmon-pidfile", ctr.config.ConmonPidFile)
+ // create the attach pipe to allow attach socket to be created before
+ // $RUNTIME exec starts running. This is to make sure we can capture all output
+ // from the process through that socket, rather than half reading the log, half attaching to the socket
+ // attachToExec is responsible for closing parentAttachPipe
+ parentAttachPipe, childAttachPipe, err := newPipe()
+ if err != nil {
+ return -1, nil, errors.Wrapf(err, "error creating socket pair")
}
- if len(ctr.config.ExitCommand) > 0 {
- args = append(args, "--exit-command", ctr.config.ExitCommand[0])
- for _, arg := range ctr.config.ExitCommand[1:] {
- args = append(args, []string{"--exit-command-arg", arg}...)
+
+ defer func() {
+ if !attachToExecCalled {
+ errorhandling.CloseQuiet(parentAttachPipe)
}
- }
- args = append(args, "--socket-dir-path", r.socketsDir)
- if ctr.config.Spec.Process.Terminal {
- args = append(args, "-t")
- } else if ctr.config.Stdin {
- args = append(args, "-i")
- }
- if r.logSizeMax >= 0 {
- args = append(args, "--log-size-max", fmt.Sprintf("%v", r.logSizeMax))
+ }()
+
+ childrenClosed := false
+ defer func() {
+ if !childrenClosed {
+ errorhandling.CloseQuiet(childSyncPipe)
+ errorhandling.CloseQuiet(childAttachPipe)
+ errorhandling.CloseQuiet(childStartPipe)
+ }
+ }()
+
+ runtimeDir, err := util.GetRootlessRuntimeDir()
+ if err != nil {
+ return -1, nil, err
}
- logDriver := KubernetesLogging
- if ctr.LogDriver() == JSONLogging {
- logrus.Errorf("json-file logging specified but not supported. Choosing k8s-file logging instead")
- } else if ctr.LogDriver() != "" {
- logDriver = ctr.LogDriver()
+ processFile, err := prepareProcessExec(c, cmd, env, tty, cwd, user, sessionID)
+ if err != nil {
+ return -1, nil, err
}
- args = append(args, "-l", fmt.Sprintf("%s:%s", logDriver, ctr.LogPath()))
- if r.noPivot {
- args = append(args, "--no-pivot")
+ var ociLog string
+ if logrus.GetLevel() != logrus.DebugLevel && r.supportsJSON {
+ ociLog = c.execOCILog(sessionID)
}
+ args := r.sharedConmonArgs(c, sessionID, c.execBundlePath(sessionID), c.execPidPath(sessionID), c.execLogPath(sessionID), c.execExitFileDir(sessionID), ociLog)
- args = append(args, "--log-level", logLevel.String())
+ if preserveFDs > 0 {
+ args = append(args, formatRuntimeOpts("--preserve-fds", string(preserveFDs))...)
+ }
- if logLevel == logrus.DebugLevel {
- logrus.Debugf("%s messages will be logged to syslog", r.conmonPath)
- args = append(args, "--syslog")
+ for _, capability := range capAdd {
+ args = append(args, formatRuntimeOpts("--cap", capability)...)
}
- if restoreOptions != nil {
- args = append(args, "--restore", ctr.CheckpointPath())
- if restoreOptions.TCPEstablished {
- args = append(args, "--restore-arg", "--tcp-established")
- }
+ if tty {
+ args = append(args, "-t")
}
+ // Append container ID and command
+ args = append(args, "-e")
+ // TODO make this optional when we can detach
+ args = append(args, "--exec-attach")
+ args = append(args, "--exec-process-spec", processFile.Name())
+
logrus.WithFields(logrus.Fields{
"args": args,
}).Debugf("running conmon: %s", r.conmonPath)
+ execCmd := exec.Command(r.conmonPath, args...)
- cmd := exec.Command(r.conmonPath, args...)
- cmd.Dir = ctr.bundlePath()
- cmd.SysProcAttr = &syscall.SysProcAttr{
- Setpgid: true,
+ if streams.AttachInput {
+ execCmd.Stdin = streams.InputStream
}
- // TODO this is probably a really bad idea for some uses
- // Make this configurable
- cmd.Stdin = os.Stdin
- cmd.Stdout = os.Stdout
- cmd.Stderr = os.Stderr
- if ctr.config.Spec.Process.Terminal {
- cmd.Stderr = &stderrBuf
- }
-
- cmd.ExtraFiles = append(cmd.ExtraFiles, childPipe, childStartPipe)
- // 0, 1 and 2 are stdin, stdout and stderr
- cmd.Env = append(r.conmonEnv, fmt.Sprintf("_OCI_SYNCPIPE=%d", 3))
- cmd.Env = append(cmd.Env, fmt.Sprintf("_OCI_STARTPIPE=%d", 4))
- cmd.Env = append(cmd.Env, fmt.Sprintf("XDG_RUNTIME_DIR=%s", runtimeDir))
- cmd.Env = append(cmd.Env, fmt.Sprintf("_CONTAINERS_USERNS_CONFIGURED=%s", os.Getenv("_CONTAINERS_USERNS_CONFIGURED")))
- cmd.Env = append(cmd.Env, fmt.Sprintf("_CONTAINERS_ROOTLESS_UID=%s", os.Getenv("_CONTAINERS_ROOTLESS_UID")))
- home, err := homeDir()
- if err != nil {
- return err
+ if streams.AttachOutput {
+ execCmd.Stdout = streams.OutputStream
+ }
+ if streams.AttachError {
+ execCmd.Stderr = streams.ErrorStream
}
- cmd.Env = append(cmd.Env, fmt.Sprintf("HOME=%s", home))
-
- if r.reservePorts && !ctr.config.NetMode.IsSlirp4netns() {
- ports, err := bindPorts(ctr.config.PortMappings)
- if err != nil {
- return err
- }
- // Leak the port we bound in the conmon process. These fd's won't be used
- // by the container and conmon will keep the ports busy so that another
- // process cannot use them.
- cmd.ExtraFiles = append(cmd.ExtraFiles, ports...)
+ conmonEnv, extraFiles, err := r.configureConmonEnv(runtimeDir)
+ if err != nil {
+ return -1, nil, err
}
- if ctr.config.NetMode.IsSlirp4netns() {
- ctr.rootlessSlirpSyncR, ctr.rootlessSlirpSyncW, err = os.Pipe()
- if err != nil {
- return errors.Wrapf(err, "failed to create rootless network sync pipe")
- }
- // Leak one end in conmon, the other one will be leaked into slirp4netns
- cmd.ExtraFiles = append(cmd.ExtraFiles, ctr.rootlessSlirpSyncW)
- }
-
- if notify, ok := os.LookupEnv("NOTIFY_SOCKET"); ok {
- cmd.Env = append(cmd.Env, fmt.Sprintf("NOTIFY_SOCKET=%s", notify))
- }
- if listenfds, ok := os.LookupEnv("LISTEN_FDS"); ok {
- cmd.Env = append(cmd.Env, fmt.Sprintf("LISTEN_FDS=%s", listenfds), "LISTEN_PID=1")
- fds := activation.Files(false)
- cmd.ExtraFiles = append(cmd.ExtraFiles, fds...)
- }
- if selinux.GetEnabled() {
- // Set the label of the conmon process to be level :s0
- // This will allow the container processes to talk to fifo-files
- // passed into the container by conmon
- var (
- plabel string
- con selinux.Context
- )
- plabel, err = selinux.CurrentLabel()
- if err != nil {
- if err := childPipe.Close(); err != nil {
- logrus.Errorf("failed to close child pipe: %q", err)
- }
- return errors.Wrapf(err, "Failed to get current SELinux label")
- }
+ // we don't want to step on users fds they asked to preserve
+ // Since 0-2 are used for stdio, start the fds we pass in at preserveFDs+3
+ execCmd.Env = append(r.conmonEnv, fmt.Sprintf("_OCI_SYNCPIPE=%d", preserveFDs+3), fmt.Sprintf("_OCI_STARTPIPE=%d", preserveFDs+4), fmt.Sprintf("_OCI_ATTACHPIPE=%d", preserveFDs+5))
+ execCmd.Env = append(execCmd.Env, conmonEnv...)
- con, err = selinux.NewContext(plabel)
- if err != nil {
- return errors.Wrapf(err, "Failed to get new context from SELinux label")
- }
+ execCmd.ExtraFiles = append(execCmd.ExtraFiles, childSyncPipe, childStartPipe, childAttachPipe)
+ execCmd.ExtraFiles = append(execCmd.ExtraFiles, extraFiles...)
+ execCmd.Dir = c.execBundlePath(sessionID)
+ execCmd.SysProcAttr = &syscall.SysProcAttr{
+ Setpgid: true,
+ }
- runtime.LockOSThread()
- if con["level"] != "s0" && con["level"] != "" {
- con["level"] = "s0"
- if err = label.SetProcessLabel(con.Get()); err != nil {
- runtime.UnlockOSThread()
- return err
- }
+ if preserveFDs > 0 {
+ for fd := 3; fd < 3+preserveFDs; fd++ {
+ execCmd.ExtraFiles = append(execCmd.ExtraFiles, os.NewFile(uintptr(fd), fmt.Sprintf("fd-%d", fd)))
}
- err = cmd.Start()
- // Ignore error returned from SetProcessLabel("") call,
- // can't recover.
- if err := label.SetProcessLabel(""); err != nil {
- _ = err
- }
- runtime.UnlockOSThread()
- } else {
- err = cmd.Start()
}
- if err != nil {
- errorhandling.CloseQuiet(childPipe)
- return err
- }
- defer func() {
- _ = cmd.Wait()
- }()
- // We don't need childPipe on the parent side
- if err := childPipe.Close(); err != nil {
- return err
- }
- if err := childStartPipe.Close(); err != nil {
- return err
- }
+ err = startCommandGivenSelinux(execCmd)
- // Move conmon to specified cgroup
- if err := r.moveConmonToCgroup(ctr, cgroupParent, cmd); err != nil {
- return err
- }
+ // We don't need children pipes on the parent side
+ errorhandling.CloseQuiet(childSyncPipe)
+ errorhandling.CloseQuiet(childAttachPipe)
+ errorhandling.CloseQuiet(childStartPipe)
+ childrenClosed = true
- /* We set the cgroup, now the child can start creating children */
- someData := []byte{0}
- _, err = parentStartPipe.Write(someData)
if err != nil {
- return err
+ return -1, nil, errors.Wrapf(err, "cannot start container %s", c.ID())
}
-
- /* Wait for initial setup and fork, and reap child */
- err = cmd.Wait()
- if err != nil {
- return err
+ if err := r.moveConmonToCgroupAndSignal(c, execCmd, parentStartPipe, sessionID); err != nil {
+ return -1, nil, err
}
- defer func() {
- if err != nil {
- if err2 := r.deleteContainer(ctr); err2 != nil {
- logrus.Errorf("Error removing container %s from runtime after creation failed", ctr.ID())
+ if preserveFDs > 0 {
+ for fd := 3; fd < 3+preserveFDs; fd++ {
+ // These fds were passed down to the runtime. Close them
+ // and not interfere
+ if err := os.NewFile(uintptr(fd), fmt.Sprintf("fd-%d", fd)).Close(); err != nil {
+ logrus.Debugf("unable to close file fd-%d", fd)
}
}
- }()
-
- // Wait to get container pid from conmon
- type syncStruct struct {
- si *syncInfo
- err error
}
- ch := make(chan syncStruct)
+
+ // TODO Only create if !detach
+ // Attach to the container before starting it
+ attachChan := make(chan error)
go func() {
- var si *syncInfo
- rdr := bufio.NewReader(parentPipe)
- b, err := rdr.ReadBytes('\n')
- if err != nil {
- ch <- syncStruct{err: err}
- }
- if err := json.Unmarshal(b, &si); err != nil {
- ch <- syncStruct{err: err}
- return
- }
- ch <- syncStruct{si: si}
+ // attachToExec is responsible for closing pipes
+ attachChan <- c.attachToExec(streams, detachKeys, resize, sessionID, parentStartPipe, parentAttachPipe)
+ close(attachChan)
}()
+ attachToExecCalled = true
- select {
- case ss := <-ch:
- if ss.err != nil {
- return errors.Wrapf(ss.err, "error reading container (probably exited) json message")
- }
- logrus.Debugf("Received container pid: %d", ss.si.Pid)
- if ss.si.Pid == -1 {
- if r.supportsJSON {
- data, err := ioutil.ReadFile(ociLog)
- if err == nil {
- var ociErr ociError
- if err := json.Unmarshal(data, &ociErr); err == nil {
- return errors.Wrapf(define.ErrOCIRuntime, "%s", strings.Trim(ociErr.Msg, "\n"))
- }
- }
- }
- // If we failed to parse the JSON errors, then print the output as it is
- if ss.si.Message != "" {
- return errors.Wrapf(define.ErrOCIRuntime, "%s", ss.si.Message)
- }
- return errors.Wrapf(define.ErrInternal, "container create failed")
- }
- ctr.state.PID = ss.si.Pid
- // Let's try reading the Conmon pid at the same time.
- if ctr.config.ConmonPidFile != "" {
- contents, err := ioutil.ReadFile(ctr.config.ConmonPidFile)
- if err != nil {
- logrus.Warnf("Error reading Conmon pidfile for container %s: %v", ctr.ID(), err)
- } else {
- // Convert it to an int
- conmonPID, err := strconv.Atoi(string(contents))
- if err != nil {
- logrus.Warnf("Error decoding Conmon PID %q for container %s: %v", string(contents), ctr.ID(), err)
- } else {
- ctr.state.ConmonPID = conmonPID
- logrus.Infof("Got Conmon PID as %d", conmonPID)
- }
- }
- }
- case <-time.After(ContainerCreateTimeout):
- return errors.Wrapf(define.ErrInternal, "container creation timeout")
- }
- return nil
+ pid, err := readConmonPipeData(parentSyncPipe, ociLog)
+
+ return pid, attachChan, err
}
// Wait for a container which has been sent a signal to stop
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-11-14 01:48:37 +0000