Add generated file

This PR adds generated files under pkg/client and vendor folder.

vendor/k8s.io/kubernetes/pkg/util/mount/nsenter_mount.go

@@ -0,0 +1,452 @@
+// +build linux
+
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"syscall"
+
+	"github.com/golang/glog"
+	"golang.org/x/sys/unix"
+	utilfile "k8s.io/kubernetes/pkg/util/file"
+	"k8s.io/kubernetes/pkg/util/nsenter"
+)
+
+const (
+	// hostProcMountsPath is the default mount path for rootfs
+	hostProcMountsPath = "/rootfs/proc/1/mounts"
+	// hostProcMountinfoPath is the default mount info path for rootfs
+	hostProcMountinfoPath = "/rootfs/proc/1/mountinfo"
+)
+
+// Currently, all docker containers receive their own mount namespaces.
+// NsenterMounter works by executing nsenter to run commands in
+// the host's mount namespace.
+type NsenterMounter struct {
+	ne *nsenter.Nsenter
+	// rootDir is location of /var/lib/kubelet directory.
+	rootDir string
+}
+
+// NewNsenterMounter creates a new mounter for kubelet that runs as a container.
+func NewNsenterMounter(rootDir string, ne *nsenter.Nsenter) *NsenterMounter {
+	return &NsenterMounter{
+		rootDir: rootDir,
+		ne:      ne,
+	}
+}
+
+// NsenterMounter implements mount.Interface
+var _ = Interface(&NsenterMounter{})
+
+// Mount runs mount(8) in the host's root mount namespace.  Aside from this
+// aspect, Mount has the same semantics as the mounter returned by mount.New()
+func (n *NsenterMounter) Mount(source string, target string, fstype string, options []string) error {
+	bind, bindRemountOpts := isBind(options)
+
+	if bind {
+		err := n.doNsenterMount(source, target, fstype, []string{"bind"})
+		if err != nil {
+			return err
+		}
+		return n.doNsenterMount(source, target, fstype, bindRemountOpts)
+	}
+
+	return n.doNsenterMount(source, target, fstype, options)
+}
+
+// doNsenterMount nsenters the host's mount namespace and performs the
+// requested mount.
+func (n *NsenterMounter) doNsenterMount(source, target, fstype string, options []string) error {
+	glog.V(5).Infof("nsenter mount %s %s %s %v", source, target, fstype, options)
+	cmd, args := n.makeNsenterArgs(source, target, fstype, options)
+	outputBytes, err := n.ne.Exec(cmd, args).CombinedOutput()
+	if len(outputBytes) != 0 {
+		glog.V(5).Infof("Output of mounting %s to %s: %v", source, target, string(outputBytes))
+	}
+	return err
+}
+
+// makeNsenterArgs makes a list of argument to nsenter in order to do the
+// requested mount.
+func (n *NsenterMounter) makeNsenterArgs(source, target, fstype string, options []string) (string, []string) {
+	mountCmd := n.ne.AbsHostPath("mount")
+	mountArgs := makeMountArgs(source, target, fstype, options)
+
+	if systemdRunPath, hasSystemd := n.ne.SupportsSystemd(); hasSystemd {
+		// Complete command line:
+		// nsenter --mount=/rootfs/proc/1/ns/mnt -- /bin/systemd-run --description=... --scope -- /bin/mount -t <type> <what> <where>
+		// Expected flow is:
+		// * nsenter breaks out of container's mount namespace and executes
+		//   host's systemd-run.
+		// * systemd-run creates a transient scope (=~ cgroup) and executes its
+		//   argument (/bin/mount) there.
+		// * mount does its job, forks a fuse daemon if necessary and finishes.
+		//   (systemd-run --scope finishes at this point, returning mount's exit
+		//   code and stdout/stderr - thats one of --scope benefits).
+		// * systemd keeps the fuse daemon running in the scope (i.e. in its own
+		//   cgroup) until the fuse daemon dies (another --scope benefit).
+		//   Kubelet container can be restarted and the fuse daemon survives.
+		// * When the daemon dies (e.g. during unmount) systemd removes the
+		//   scope automatically.
+		mountCmd, mountArgs = addSystemdScope(systemdRunPath, target, mountCmd, mountArgs)
+	} else {
+		// Fall back to simple mount when the host has no systemd.
+		// Complete command line:
+		// nsenter --mount=/rootfs/proc/1/ns/mnt -- /bin/mount -t <type> <what> <where>
+		// Expected flow is:
+		// * nsenter breaks out of container's mount namespace and executes host's /bin/mount.
+		// * mount does its job, forks a fuse daemon if necessary and finishes.
+		// * Any fuse daemon runs in cgroup of kubelet docker container,
+		//   restart of kubelet container will kill it!
+
+		// No code here, mountCmd and mountArgs use /bin/mount
+	}
+
+	return mountCmd, mountArgs
+}
+
+// Unmount runs umount(8) in the host's mount namespace.
+func (n *NsenterMounter) Unmount(target string) error {
+	args := []string{target}
+	// No need to execute systemd-run here, it's enough that unmount is executed
+	// in the host's mount namespace. It will finish appropriate fuse daemon(s)
+	// running in any scope.
+	glog.V(5).Infof("nsenter unmount args: %v", args)
+	outputBytes, err := n.ne.Exec("umount", args).CombinedOutput()
+	if len(outputBytes) != 0 {
+		glog.V(5).Infof("Output of unmounting %s: %v", target, string(outputBytes))
+	}
+	return err
+}
+
+// List returns a list of all mounted filesystems in the host's mount namespace.
+func (*NsenterMounter) List() ([]MountPoint, error) {
+	return listProcMounts(hostProcMountsPath)
+}
+
+func (m *NsenterMounter) IsNotMountPoint(dir string) (bool, error) {
+	return IsNotMountPoint(m, dir)
+}
+
+func (*NsenterMounter) IsMountPointMatch(mp MountPoint, dir string) bool {
+	deletedDir := fmt.Sprintf("%s\\040(deleted)", dir)
+	return (mp.Path == dir) || (mp.Path == deletedDir)
+}
+
+// IsLikelyNotMountPoint determines whether a path is a mountpoint by calling findmnt
+// in the host's root mount namespace.
+func (n *NsenterMounter) IsLikelyNotMountPoint(file string) (bool, error) {
+	file, err := filepath.Abs(file)
+	if err != nil {
+		return true, err
+	}
+
+	// Check the directory exists
+	if _, err = os.Stat(file); os.IsNotExist(err) {
+		glog.V(5).Infof("findmnt: directory %s does not exist", file)
+		return true, err
+	}
+	// Add --first-only option: since we are testing for the absence of a mountpoint, it is sufficient to get only
+	// the first of multiple possible mountpoints using --first-only.
+	// Also add fstype output to make sure that the output of target file will give the full path
+	// TODO: Need more refactoring for this function. Track the solution with issue #26996
+	args := []string{"-o", "target,fstype", "--noheadings", "--first-only", "--target", file}
+	glog.V(5).Infof("nsenter findmnt args: %v", args)
+	out, err := n.ne.Exec("findmnt", args).CombinedOutput()
+	if err != nil {
+		glog.V(2).Infof("Failed findmnt command for path %s: %s %v", file, out, err)
+		// Different operating systems behave differently for paths which are not mount points.
+		// On older versions (e.g. 2.20.1) we'd get error, on newer ones (e.g. 2.26.2) we'd get "/".
+		// It's safer to assume that it's not a mount point.
+		return true, nil
+	}
+	mountTarget, err := parseFindMnt(string(out))
+	if err != nil {
+		return false, err
+	}
+
+	glog.V(5).Infof("IsLikelyNotMountPoint findmnt output for path %s: %v:", file, mountTarget)
+
+	if mountTarget == file {
+		glog.V(5).Infof("IsLikelyNotMountPoint: %s is a mount point", file)
+		return false, nil
+	}
+	glog.V(5).Infof("IsLikelyNotMountPoint: %s is not a mount point", file)
+	return true, nil
+}
+
+// parse output of "findmnt -o target,fstype" and return just the target
+func parseFindMnt(out string) (string, error) {
+	// cut trailing newline
+	out = strings.TrimSuffix(out, "\n")
+	// cut everything after the last space - it's the filesystem type
+	i := strings.LastIndex(out, " ")
+	if i == -1 {
+		return "", fmt.Errorf("error parsing findmnt output, expected at least one space: %q", out)
+	}
+	return out[:i], nil
+}
+
+// DeviceOpened checks if block device in use by calling Open with O_EXCL flag.
+// Returns true if open returns errno EBUSY, and false if errno is nil.
+// Returns an error if errno is any error other than EBUSY.
+// Returns with error if pathname is not a device.
+func (n *NsenterMounter) DeviceOpened(pathname string) (bool, error) {
+	return exclusiveOpenFailsOnDevice(pathname)
+}
+
+// PathIsDevice uses FileInfo returned from os.Stat to check if path refers
+// to a device.
+func (n *NsenterMounter) PathIsDevice(pathname string) (bool, error) {
+	pathType, err := n.GetFileType(pathname)
+	isDevice := pathType == FileTypeCharDev || pathType == FileTypeBlockDev
+	return isDevice, err
+}
+
+//GetDeviceNameFromMount given a mount point, find the volume id from checking /proc/mounts
+func (n *NsenterMounter) GetDeviceNameFromMount(mountPath, pluginDir string) (string, error) {
+	return getDeviceNameFromMount(n, mountPath, pluginDir)
+}
+
+func (n *NsenterMounter) MakeRShared(path string) error {
+	return doMakeRShared(path, hostProcMountinfoPath)
+}
+
+func (mounter *NsenterMounter) GetFileType(pathname string) (FileType, error) {
+	var pathType FileType
+	outputBytes, err := mounter.ne.Exec("stat", []string{"-L", "--printf=%F", pathname}).CombinedOutput()
+	if err != nil {
+		if strings.Contains(string(outputBytes), "No such file") {
+			err = fmt.Errorf("%s does not exist", pathname)
+		} else {
+			err = fmt.Errorf("stat %s error: %v", pathname, string(outputBytes))
+		}
+		return pathType, err
+	}
+
+	switch string(outputBytes) {
+	case "socket":
+		return FileTypeSocket, nil
+	case "character special file":
+		return FileTypeCharDev, nil
+	case "block special file":
+		return FileTypeBlockDev, nil
+	case "directory":
+		return FileTypeDirectory, nil
+	case "regular file":
+		return FileTypeFile, nil
+	}
+
+	return pathType, fmt.Errorf("only recognise file, directory, socket, block device and character device")
+}
+
+func (mounter *NsenterMounter) MakeDir(pathname string) error {
+	args := []string{"-p", pathname}
+	if _, err := mounter.ne.Exec("mkdir", args).CombinedOutput(); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (mounter *NsenterMounter) MakeFile(pathname string) error {
+	args := []string{pathname}
+	if _, err := mounter.ne.Exec("touch", args).CombinedOutput(); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (mounter *NsenterMounter) ExistsPath(pathname string) (bool, error) {
+	// Resolve the symlinks but allow the target not to exist. EvalSymlinks
+	// would return an generic error when the target does not exist.
+	hostPath, err := mounter.ne.EvalSymlinks(pathname, false /* mustExist */)
+	if err != nil {
+		return false, err
+	}
+	kubeletpath := mounter.ne.KubeletPath(hostPath)
+	return utilfile.FileExists(kubeletpath)
+}
+
+func (mounter *NsenterMounter) CleanSubPaths(podDir string, volumeName string) error {
+	return doCleanSubPaths(mounter, podDir, volumeName)
+}
+
+func (mounter *NsenterMounter) PrepareSafeSubpath(subPath Subpath) (newHostPath string, cleanupAction func(), err error) {
+	// Bind-mount the subpath to avoid using symlinks in subpaths.
+	newHostPath, err = doNsEnterBindSubPath(mounter, subPath)
+
+	// There is no action when the container starts. Bind-mount will be cleaned
+	// when container stops by CleanSubPaths.
+	cleanupAction = nil
+	return newHostPath, cleanupAction, err
+}
+
+func (mounter *NsenterMounter) SafeMakeDir(subdir string, base string, perm os.FileMode) error {
+	fullSubdirPath := filepath.Join(base, subdir)
+	evaluatedSubdirPath, err := mounter.ne.EvalSymlinks(fullSubdirPath, false /* mustExist */)
+	if err != nil {
+		return fmt.Errorf("error resolving symlinks in %s: %s", fullSubdirPath, err)
+	}
+	evaluatedSubdirPath = filepath.Clean(evaluatedSubdirPath)
+
+	evaluatedBase, err := mounter.ne.EvalSymlinks(base, true /* mustExist */)
+	if err != nil {
+		return fmt.Errorf("error resolving symlinks in %s: %s", base, err)
+	}
+	evaluatedBase = filepath.Clean(evaluatedBase)
+
+	rootDir := filepath.Clean(mounter.rootDir)
+	if pathWithinBase(evaluatedBase, rootDir) {
+		// Base is in /var/lib/kubelet. This directory is shared between the
+		// container with kubelet and the host. We don't need to add '/rootfs'.
+		// This is useful when /rootfs is mounted as read-only - we can still
+		// create subpaths for paths in /var/lib/kubelet.
+		return doSafeMakeDir(evaluatedSubdirPath, evaluatedBase, perm)
+	}
+
+	// Base is somewhere on the host's filesystem. Add /rootfs and try to make
+	// the directory there.
+	// This requires /rootfs to be writable.
+	kubeletSubdirPath := mounter.ne.KubeletPath(evaluatedSubdirPath)
+	kubeletBase := mounter.ne.KubeletPath(evaluatedBase)
+	return doSafeMakeDir(kubeletSubdirPath, kubeletBase, perm)
+}
+
+func (mounter *NsenterMounter) GetMountRefs(pathname string) ([]string, error) {
+	hostpath, err := mounter.ne.EvalSymlinks(pathname, true /* mustExist */)
+	if err != nil {
+		return nil, err
+	}
+	return searchMountPoints(hostpath, hostProcMountinfoPath)
+}
+
+func doNsEnterBindSubPath(mounter *NsenterMounter, subpath Subpath) (hostPath string, err error) {
+	// Linux, kubelet runs in a container:
+	// - safely open the subpath
+	// - bind-mount the subpath to target (this can be unsafe)
+	// - check that we mounted the right thing by comparing device ID and inode
+	//   of the subpath (via safely opened fd) and the target (that's under our
+	//   control)
+
+	// Evaluate all symlinks here once for all subsequent functions.
+	evaluatedHostVolumePath, err := mounter.ne.EvalSymlinks(subpath.VolumePath, true /*mustExist*/)
+	if err != nil {
+		return "", fmt.Errorf("error resolving symlinks in %q: %v", subpath.VolumePath, err)
+	}
+	evaluatedHostSubpath, err := mounter.ne.EvalSymlinks(subpath.Path, true /*mustExist*/)
+	if err != nil {
+		return "", fmt.Errorf("error resolving symlinks in %q: %v", subpath.Path, err)
+	}
+	glog.V(5).Infof("doBindSubPath %q (%q) for volumepath %q", subpath.Path, evaluatedHostSubpath, subpath.VolumePath)
+	subpath.VolumePath = mounter.ne.KubeletPath(evaluatedHostVolumePath)
+	subpath.Path = mounter.ne.KubeletPath(evaluatedHostSubpath)
+
+	// Check the subpath is correct and open it
+	fd, err := safeOpenSubPath(mounter, subpath)
+	if err != nil {
+		return "", err
+	}
+	defer syscall.Close(fd)
+
+	alreadyMounted, bindPathTarget, err := prepareSubpathTarget(mounter, subpath)
+	if err != nil {
+		return "", err
+	}
+	if alreadyMounted {
+		return bindPathTarget, nil
+	}
+
+	success := false
+	defer func() {
+		// Cleanup subpath on error
+		if !success {
+			glog.V(4).Infof("doNsEnterBindSubPath() failed for %q, cleaning up subpath", bindPathTarget)
+			if cleanErr := cleanSubPath(mounter, subpath); cleanErr != nil {
+				glog.Errorf("Failed to clean subpath %q: %v", bindPathTarget, cleanErr)
+			}
+		}
+	}()
+
+	// Leap of faith: optimistically expect that nobody has modified previously
+	// expanded evalSubPath with evil symlinks and bind-mount it.
+	// Mount is done on the host! don't use kubelet path!
+	glog.V(5).Infof("bind mounting %q at %q", evaluatedHostSubpath, bindPathTarget)
+	if err = mounter.Mount(evaluatedHostSubpath, bindPathTarget, "" /*fstype*/, []string{"bind"}); err != nil {
+		return "", fmt.Errorf("error mounting %s: %s", evaluatedHostSubpath, err)
+	}
+
+	// Check that the bind-mount target is the same inode and device as the
+	// source that we keept open, i.e. we mounted the right thing.
+	err = checkDeviceInode(fd, bindPathTarget)
+	if err != nil {
+		return "", fmt.Errorf("error checking bind mount for subpath %s: %s", subpath.VolumePath, err)
+	}
+
+	success = true
+	glog.V(3).Infof("Bound SubPath %s into %s", subpath.Path, bindPathTarget)
+	return bindPathTarget, nil
+}
+
+// checkDeviceInode checks that opened file and path represent the same file.
+func checkDeviceInode(fd int, path string) error {
+	var srcStat, dstStat unix.Stat_t
+	err := unix.Fstat(fd, &srcStat)
+	if err != nil {
+		return fmt.Errorf("error running fstat on subpath FD: %v", err)
+	}
+
+	err = unix.Stat(path, &dstStat)
+	if err != nil {
+		return fmt.Errorf("error running fstat on %s: %v", path, err)
+	}
+
+	if srcStat.Dev != dstStat.Dev {
+		return fmt.Errorf("different device number")
+	}
+	if srcStat.Ino != dstStat.Ino {
+		return fmt.Errorf("different inode")
+	}
+	return nil
+}
+
+func (mounter *NsenterMounter) GetFSGroup(pathname string) (int64, error) {
+	hostPath, err := mounter.ne.EvalSymlinks(pathname, true /* mustExist */)
+	if err != nil {
+		return -1, err
+	}
+	kubeletpath := mounter.ne.KubeletPath(hostPath)
+	return getFSGroup(kubeletpath)
+}
+
+func (mounter *NsenterMounter) GetSELinuxSupport(pathname string) (bool, error) {
+	return getSELinuxSupport(pathname, hostProcMountsPath)
+}
+
+func (mounter *NsenterMounter) GetMode(pathname string) (os.FileMode, error) {
+	hostPath, err := mounter.ne.EvalSymlinks(pathname, true /* mustExist */)
+	if err != nil {
+		return 0, err
+	}
+	kubeletpath := mounter.ne.KubeletPath(hostPath)
+	return getMode(kubeletpath)
+}