cri-o/server/container_create.go
Ryan Cole f3efb850b7 Remove ImageSpec dependency from server
Signed-off-by: Ryan Cole <rcyoalne@gmail.com>
2017-07-17 16:21:56 -04:00

817 lines
24 KiB
Go

package server
import (
"encoding/json"
"errors"
"fmt"
"io"
"os"
"path/filepath"
"strconv"
"strings"
"time"
"github.com/Sirupsen/logrus"
"github.com/docker/docker/pkg/stringid"
"github.com/docker/docker/pkg/symlink"
"github.com/kubernetes-incubator/cri-o/oci"
"github.com/kubernetes-incubator/cri-o/pkg/annotations"
"github.com/kubernetes-incubator/cri-o/pkg/storage"
"github.com/kubernetes-incubator/cri-o/server/apparmor"
"github.com/kubernetes-incubator/cri-o/server/seccomp"
"github.com/opencontainers/image-spec/specs-go/v1"
"github.com/opencontainers/runc/libcontainer/cgroups"
"github.com/opencontainers/runc/libcontainer/devices"
"github.com/opencontainers/runc/libcontainer/user"
rspec "github.com/opencontainers/runtime-spec/specs-go"
"github.com/opencontainers/runtime-tools/generate"
"github.com/opencontainers/selinux/go-selinux/label"
"golang.org/x/net/context"
"golang.org/x/sys/unix"
pb "k8s.io/kubernetes/pkg/kubelet/api/v1alpha1/runtime"
)
const (
seccompUnconfined = "unconfined"
seccompRuntimeDefault = "runtime/default"
seccompLocalhostPrefix = "localhost/"
)
func addOCIBindMounts(sb *sandbox, containerConfig *pb.ContainerConfig, specgen *generate.Generator) error {
mounts := containerConfig.GetMounts()
for _, mount := range mounts {
dest := mount.ContainerPath
if dest == "" {
return fmt.Errorf("Mount.ContainerPath is empty")
}
src := mount.HostPath
if src == "" {
return fmt.Errorf("Mount.HostPath is empty")
}
if _, err := os.Stat(src); err != nil && os.IsNotExist(err) {
if err1 := os.MkdirAll(src, 0644); err1 != nil {
return fmt.Errorf("Failed to mkdir %s: %s", src, err)
}
}
options := []string{"rw"}
if mount.Readonly {
options = []string{"ro"}
}
if mount.SelinuxRelabel {
// Need a way in kubernetes to determine if the volume is shared or private
if err := label.Relabel(src, sb.mountLabel, true); err != nil && err != unix.ENOTSUP {
return fmt.Errorf("relabel failed %s: %v", src, err)
}
}
specgen.AddBindMount(src, dest, options)
}
return nil
}
func addImageVolumes(rootfs string, s *Server, containerInfo *storage.ContainerInfo, specgen *generate.Generator, mountLabel string) error {
for dest := range containerInfo.Config.Config.Volumes {
fp, err := symlink.FollowSymlinkInScope(filepath.Join(rootfs, dest), rootfs)
if err != nil {
return err
}
switch s.config.ImageVolumes {
case ImageVolumesMkdir:
if err1 := os.MkdirAll(fp, 0644); err1 != nil {
return err1
}
case ImageVolumesBind:
volumeDirName := stringid.GenerateNonCryptoID()
src := filepath.Join(containerInfo.RunDir, "mounts", volumeDirName)
if err1 := os.MkdirAll(src, 0644); err1 != nil {
return err1
}
// Label the source with the sandbox selinux mount label
if mountLabel != "" {
if err1 := label.Relabel(src, mountLabel, true); err1 != nil && err1 != unix.ENOTSUP {
return fmt.Errorf("relabel failed %s: %v", src, err1)
}
}
logrus.Debugf("Adding bind mounted volume: %s to %s", src, dest)
specgen.AddBindMount(src, dest, []string{"rw"})
case ImageVolumesIgnore:
logrus.Debugf("Ignoring volume %v", dest)
default:
logrus.Fatalf("Unrecognized image volumes setting")
}
}
return nil
}
func addDevices(sb *sandbox, containerConfig *pb.ContainerConfig, specgen *generate.Generator) error {
sp := specgen.Spec()
for _, device := range containerConfig.GetDevices() {
dev, err := devices.DeviceFromPath(device.HostPath, device.Permissions)
if err != nil {
return fmt.Errorf("failed to add device: %v", err)
}
rd := rspec.LinuxDevice{
Path: device.ContainerPath,
Type: string(dev.Type),
Major: dev.Major,
Minor: dev.Minor,
UID: &dev.Uid,
GID: &dev.Gid,
}
specgen.AddDevice(rd)
sp.Linux.Resources.Devices = append(sp.Linux.Resources.Devices, rspec.LinuxDeviceCgroup{
Allow: true,
Type: string(dev.Type),
Major: &dev.Major,
Minor: &dev.Minor,
Access: dev.Permissions,
})
}
return nil
}
// buildOCIProcessArgs build an OCI compatible process arguments slice.
func buildOCIProcessArgs(containerKubeConfig *pb.ContainerConfig, imageOCIConfig *v1.Image) ([]string, error) {
//# Start the nginx container using the default command, but use custom
//arguments (arg1 .. argN) for that command.
//kubectl run nginx --image=nginx -- <arg1> <arg2> ... <argN>
//# Start the nginx container using a different command and custom arguments.
//kubectl run nginx --image=nginx --command -- <cmd> <arg1> ... <argN>
kubeCommands := containerKubeConfig.Command
kubeArgs := containerKubeConfig.Args
// merge image config and kube config
// same as docker does today...
if imageOCIConfig != nil {
if len(kubeCommands) == 0 {
if len(kubeArgs) == 0 {
kubeArgs = imageOCIConfig.Config.Cmd
}
if kubeCommands == nil {
kubeCommands = imageOCIConfig.Config.Entrypoint
}
}
}
if len(kubeCommands) == 0 && len(kubeArgs) == 0 {
return nil, fmt.Errorf("no command specified")
}
// create entrypoint and args
var entrypoint string
var args []string
if len(kubeCommands) != 0 {
entrypoint = kubeCommands[0]
args = append(kubeCommands[1:], kubeArgs...)
} else {
entrypoint = kubeArgs[0]
args = kubeArgs[1:]
}
processArgs := append([]string{entrypoint}, args...)
logrus.Debugf("OCI process args %v", processArgs)
return processArgs, nil
}
// setupContainerUser sets the UID, GID and supplemental groups in OCI runtime config
func setupContainerUser(specgen *generate.Generator, rootfs string, sc *pb.LinuxContainerSecurityContext, imageConfig *v1.Image) error {
if sc != nil {
containerUser := ""
// Case 1: run as user is set by kubelet
if sc.RunAsUser != nil {
containerUser = strconv.FormatInt(sc.GetRunAsUser().Value, 10)
} else {
// Case 2: run as username is set by kubelet
userName := sc.RunAsUsername
if userName != "" {
containerUser = userName
} else {
// Case 3: get user from image config
if imageConfig != nil {
imageUser := imageConfig.Config.User
if imageUser != "" {
containerUser = imageUser
}
}
}
}
logrus.Debugf("CONTAINER USER: %+v", containerUser)
// Add uid, gid and groups from user
uid, gid, addGroups, err1 := getUserInfo(rootfs, containerUser)
if err1 != nil {
return err1
}
logrus.Debugf("UID: %v, GID: %v, Groups: %+v", uid, gid, addGroups)
specgen.SetProcessUID(uid)
specgen.SetProcessGID(gid)
for _, group := range addGroups {
specgen.AddProcessAdditionalGid(group)
}
// Add groups from CRI
groups := sc.SupplementalGroups
for _, group := range groups {
specgen.AddProcessAdditionalGid(uint32(group))
}
}
return nil
}
func hostNetwork(containerConfig *pb.ContainerConfig) bool {
securityContext := containerConfig.GetLinux().GetSecurityContext()
if securityContext == nil || securityContext.GetNamespaceOptions() == nil {
return false
}
return securityContext.GetNamespaceOptions().HostNetwork
}
// ensureSaneLogPath is a hack to fix https://issues.k8s.io/44043 which causes
// logPath to be a broken symlink to some magical Docker path. Ideally we
// wouldn't have to deal with this, but until that issue is fixed we have to
// remove the path if it's a broken symlink.
func ensureSaneLogPath(logPath string) error {
// If the path exists but the resolved path does not, then we have a broken
// symlink and we need to remove it.
fi, err := os.Lstat(logPath)
if err != nil || fi.Mode()&os.ModeSymlink == 0 {
// Non-existant files and non-symlinks aren't our problem.
return nil
}
_, err = os.Stat(logPath)
if os.IsNotExist(err) {
err = os.RemoveAll(logPath)
if err != nil {
return fmt.Errorf("ensureSaneLogPath remove bad logPath: %s", err)
}
}
return nil
}
// CreateContainer creates a new container in specified PodSandbox
func (s *Server) CreateContainer(ctx context.Context, req *pb.CreateContainerRequest) (res *pb.CreateContainerResponse, err error) {
logrus.Debugf("CreateContainerRequest %+v", req)
s.updateLock.RLock()
defer s.updateLock.RUnlock()
sbID := req.PodSandboxId
if sbID == "" {
return nil, fmt.Errorf("PodSandboxId should not be empty")
}
sandboxID, err := s.podIDIndex.Get(sbID)
if err != nil {
return nil, fmt.Errorf("PodSandbox with ID starting with %s not found: %v", sbID, err)
}
sb := s.getSandbox(sandboxID)
if sb == nil {
return nil, fmt.Errorf("specified sandbox not found: %s", sandboxID)
}
// The config of the container
containerConfig := req.GetConfig()
if containerConfig == nil {
return nil, fmt.Errorf("CreateContainerRequest.ContainerConfig is nil")
}
name := containerConfig.GetMetadata().Name
if name == "" {
return nil, fmt.Errorf("CreateContainerRequest.ContainerConfig.Name is empty")
}
containerID, containerName, err := s.generateContainerIDandName(sb.metadata, containerConfig)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
s.releaseContainerName(containerName)
}
}()
container, err := s.createSandboxContainer(ctx, containerID, containerName, sb, req.GetSandboxConfig(), containerConfig)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
err2 := s.storageRuntimeServer.DeleteContainer(containerID)
if err2 != nil {
logrus.Warnf("Failed to cleanup container directory: %v", err2)
}
}
}()
if err = s.runtime.CreateContainer(container, sb.cgroupParent); err != nil {
return nil, err
}
if err = s.runtime.UpdateStatus(container); err != nil {
return nil, err
}
s.addContainer(container)
if err = s.ctrIDIndex.Add(containerID); err != nil {
s.removeContainer(container)
return nil, err
}
s.containerStateToDisk(container)
resp := &pb.CreateContainerResponse{
ContainerId: containerID,
}
logrus.Debugf("CreateContainerResponse: %+v", resp)
return resp, nil
}
func (s *Server) createSandboxContainer(ctx context.Context, containerID string, containerName string, sb *sandbox, SandboxConfig *pb.PodSandboxConfig, containerConfig *pb.ContainerConfig) (*oci.Container, error) {
if sb == nil {
return nil, errors.New("createSandboxContainer needs a sandbox")
}
// TODO: simplify this function (cyclomatic complexity here is high)
// TODO: factor generating/updating the spec into something other projects can vendor
// creates a spec Generator with the default spec.
specgen := generate.New()
specgen.HostSpecific = true
specgen.ClearProcessRlimits()
if err := addOCIBindMounts(sb, containerConfig, &specgen); err != nil {
return nil, err
}
// Add cgroup mount so container process can introspect its own limits
specgen.AddCgroupsMount("ro")
if err := addDevices(sb, containerConfig, &specgen); err != nil {
return nil, err
}
labels := containerConfig.GetLabels()
metadata := containerConfig.GetMetadata()
kubeAnnotations := containerConfig.GetAnnotations()
if kubeAnnotations != nil {
for k, v := range kubeAnnotations {
specgen.AddAnnotation(k, v)
}
}
// set this container's apparmor profile if it is set by sandbox
if s.appArmorEnabled {
appArmorProfileName := s.getAppArmorProfileName(sb.annotations, metadata.Name)
if appArmorProfileName != "" {
// reload default apparmor profile if it is unloaded.
if s.appArmorProfile == apparmor.DefaultApparmorProfile {
if err := apparmor.EnsureDefaultApparmorProfile(); err != nil {
return nil, err
}
}
specgen.SetProcessApparmorProfile(appArmorProfileName)
}
}
var readOnlyRootfs bool
if containerConfig.GetLinux().GetSecurityContext() != nil {
if containerConfig.GetLinux().GetSecurityContext().Privileged {
specgen.SetupPrivileged(true)
}
if containerConfig.GetLinux().GetSecurityContext().ReadonlyRootfs {
readOnlyRootfs = true
specgen.SetRootReadonly(true)
}
}
logPath := containerConfig.LogPath
if logPath == "" {
// TODO: Should we use sandboxConfig.GetLogDirectory() here?
logPath = filepath.Join(sb.logDir, containerID+".log")
}
if !filepath.IsAbs(logPath) {
// XXX: It's not really clear what this should be versus the sbox logDirectory.
logrus.Warnf("requested logPath for ctr id %s is a relative path: %s", containerID, logPath)
logPath = filepath.Join(sb.logDir, logPath)
}
// Handle https://issues.k8s.io/44043
if err := ensureSaneLogPath(logPath); err != nil {
return nil, err
}
logrus.WithFields(logrus.Fields{
"sbox.logdir": sb.logDir,
"ctr.logfile": containerConfig.LogPath,
"log_path": logPath,
}).Debugf("setting container's log_path")
specgen.SetProcessTerminal(containerConfig.Tty)
linux := containerConfig.GetLinux()
if linux != nil {
resources := linux.GetResources()
if resources != nil {
cpuPeriod := resources.CpuPeriod
if cpuPeriod != 0 {
specgen.SetLinuxResourcesCPUPeriod(uint64(cpuPeriod))
}
cpuQuota := resources.CpuQuota
if cpuQuota != 0 {
specgen.SetLinuxResourcesCPUQuota(cpuQuota)
}
cpuShares := resources.CpuShares
if cpuShares != 0 {
specgen.SetLinuxResourcesCPUShares(uint64(cpuShares))
}
memoryLimit := resources.MemoryLimitInBytes
if memoryLimit != 0 {
specgen.SetLinuxResourcesMemoryLimit(uint64(memoryLimit))
}
oomScoreAdj := resources.OomScoreAdj
specgen.SetLinuxResourcesOOMScoreAdj(int(oomScoreAdj))
}
if sb.cgroupParent != "" {
if s.config.CgroupManager == "systemd" {
cgPath := sb.cgroupParent + ":" + "crio" + ":" + containerID
specgen.SetLinuxCgroupsPath(cgPath)
} else {
specgen.SetLinuxCgroupsPath(sb.cgroupParent + "/" + containerID)
}
}
capabilities := linux.GetSecurityContext().GetCapabilities()
toCAPPrefixed := func(cap string) string {
if !strings.HasPrefix(strings.ToLower(cap), "cap_") {
return "CAP_" + cap
}
return cap
}
if capabilities != nil {
addCaps := capabilities.AddCapabilities
if addCaps != nil {
for _, cap := range addCaps {
if err := specgen.AddProcessCapability(toCAPPrefixed(cap)); err != nil {
return nil, err
}
}
}
dropCaps := capabilities.DropCapabilities
if dropCaps != nil {
for _, cap := range dropCaps {
if err := specgen.DropProcessCapability(toCAPPrefixed(cap)); err != nil {
logrus.Debugf("failed to drop cap %s: %v", toCAPPrefixed(cap), err)
}
}
}
}
specgen.SetProcessSelinuxLabel(sb.processLabel)
specgen.SetLinuxMountLabel(sb.mountLabel)
if containerConfig.GetLinux().GetSecurityContext() != nil &&
!containerConfig.GetLinux().GetSecurityContext().Privileged {
for _, mp := range []string{
"/proc/kcore",
"/proc/latency_stats",
"/proc/timer_list",
"/proc/timer_stats",
"/proc/sched_debug",
"/sys/firmware",
} {
specgen.AddLinuxMaskedPaths(mp)
}
for _, rp := range []string{
"/proc/asound",
"/proc/bus",
"/proc/fs",
"/proc/irq",
"/proc/sys",
"/proc/sysrq-trigger",
} {
specgen.AddLinuxReadonlyPaths(rp)
}
}
}
// Join the namespace paths for the pod sandbox container.
podInfraState := s.runtime.ContainerStatus(sb.infraContainer)
logrus.Debugf("pod container state %+v", podInfraState)
ipcNsPath := fmt.Sprintf("/proc/%d/ns/ipc", podInfraState.Pid)
if err := specgen.AddOrReplaceLinuxNamespace("ipc", ipcNsPath); err != nil {
return nil, err
}
netNsPath := sb.netNsPath()
if netNsPath == "" {
// The sandbox does not have a permanent namespace,
// it's on the host one.
netNsPath = fmt.Sprintf("/proc/%d/ns/net", podInfraState.Pid)
}
if err := specgen.AddOrReplaceLinuxNamespace("network", netNsPath); err != nil {
return nil, err
}
imageSpec := containerConfig.GetImage()
if imageSpec == nil {
return nil, fmt.Errorf("CreateContainerRequest.ContainerConfig.Image is nil")
}
image := imageSpec.Image
if image == "" {
return nil, fmt.Errorf("CreateContainerRequest.ContainerConfig.Image.Image is empty")
}
// bind mount the pod shm
specgen.AddBindMount(sb.shmPath, "/dev/shm", []string{"rw"})
options := []string{"rw"}
if readOnlyRootfs {
options = []string{"ro"}
}
if sb.resolvPath != "" {
// bind mount the pod resolver file
specgen.AddBindMount(sb.resolvPath, "/etc/resolv.conf", options)
}
// Bind mount /etc/hosts for host networking containers
if hostNetwork(containerConfig) {
specgen.AddBindMount("/etc/hosts", "/etc/hosts", options)
}
if sb.hostname != "" {
specgen.SetHostname(sb.hostname)
}
specgen.AddAnnotation(annotations.Name, containerName)
specgen.AddAnnotation(annotations.ContainerID, containerID)
specgen.AddAnnotation(annotations.SandboxID, sb.id)
specgen.AddAnnotation(annotations.SandboxName, sb.infraContainer.Name())
specgen.AddAnnotation(annotations.ContainerType, annotations.ContainerTypeContainer)
specgen.AddAnnotation(annotations.LogPath, logPath)
specgen.AddAnnotation(annotations.TTY, fmt.Sprintf("%v", containerConfig.Tty))
specgen.AddAnnotation(annotations.Stdin, fmt.Sprintf("%v", containerConfig.Stdin))
specgen.AddAnnotation(annotations.StdinOnce, fmt.Sprintf("%v", containerConfig.StdinOnce))
specgen.AddAnnotation(annotations.Image, image)
created := time.Now()
specgen.AddAnnotation(annotations.Created, created.Format(time.RFC3339Nano))
metadataJSON, err := json.Marshal(metadata)
if err != nil {
return nil, err
}
specgen.AddAnnotation(annotations.Metadata, string(metadataJSON))
labelsJSON, err := json.Marshal(labels)
if err != nil {
return nil, err
}
specgen.AddAnnotation(annotations.Labels, string(labelsJSON))
kubeAnnotationsJSON, err := json.Marshal(kubeAnnotations)
if err != nil {
return nil, err
}
specgen.AddAnnotation(annotations.Annotations, string(kubeAnnotationsJSON))
if err = s.setupSeccomp(&specgen, containerName, sb.annotations); err != nil {
return nil, err
}
metaname := metadata.Name
attempt := metadata.Attempt
containerInfo, err := s.storageRuntimeServer.CreateContainer(s.imageContext,
sb.name, sb.id,
image, image,
containerName, containerID,
metaname,
attempt,
sb.mountLabel,
nil)
if err != nil {
return nil, err
}
mountPoint, err := s.storageRuntimeServer.StartContainer(containerID)
if err != nil {
return nil, fmt.Errorf("failed to mount container %s(%s): %v", containerName, containerID, err)
}
containerImageConfig := containerInfo.Config
if containerImageConfig == nil {
return nil, fmt.Errorf("empty image config for %s", image)
}
if containerImageConfig.Config.StopSignal != "" {
// this key is defined in image-spec conversion document at https://github.com/opencontainers/image-spec/pull/492/files#diff-8aafbe2c3690162540381b8cdb157112R57
specgen.AddAnnotation("org.opencontainers.image.stopSignal", containerImageConfig.Config.StopSignal)
}
// Add image volumes
if err := addImageVolumes(mountPoint, s, &containerInfo, &specgen, sb.mountLabel); err != nil {
return nil, err
}
processArgs, err := buildOCIProcessArgs(containerConfig, containerImageConfig)
if err != nil {
return nil, err
}
specgen.SetProcessArgs(processArgs)
// Add environment variables from CRI and image config
envs := containerConfig.GetEnvs()
if envs != nil {
for _, item := range envs {
key := item.Key
value := item.Value
if key == "" {
continue
}
specgen.AddProcessEnv(key, value)
}
}
if containerImageConfig != nil {
for _, item := range containerImageConfig.Config.Env {
parts := strings.SplitN(item, "=", 2)
if len(parts) != 2 {
return nil, fmt.Errorf("invalid env from image: %s", item)
}
if parts[0] == "" {
continue
}
specgen.AddProcessEnv(parts[0], parts[1])
}
}
// Set working directory
// Pick it up from image config first and override if specified in CRI
containerCwd := "/"
if containerImageConfig != nil {
imageCwd := containerImageConfig.Config.WorkingDir
if imageCwd != "" {
containerCwd = imageCwd
}
}
runtimeCwd := containerConfig.WorkingDir
if runtimeCwd != "" {
containerCwd = runtimeCwd
}
specgen.SetProcessCwd(containerCwd)
// Setup user and groups
if linux != nil {
if err = setupContainerUser(&specgen, mountPoint, linux.GetSecurityContext(), containerImageConfig); err != nil {
return nil, err
}
}
// Set up pids limit if pids cgroup is mounted
_, err = cgroups.FindCgroupMountpoint("pids")
if err == nil {
specgen.SetLinuxResourcesPidsLimit(s.config.PidsLimit)
}
// by default, the root path is an empty string. set it now.
specgen.SetRootPath(mountPoint)
saveOptions := generate.ExportOptions{}
if err = specgen.SaveToFile(filepath.Join(containerInfo.Dir, "config.json"), saveOptions); err != nil {
return nil, err
}
if err = specgen.SaveToFile(filepath.Join(containerInfo.RunDir, "config.json"), saveOptions); err != nil {
return nil, err
}
container, err := oci.NewContainer(containerID, containerName, containerInfo.RunDir, logPath, sb.netNs(), labels, kubeAnnotations, image, metadata, sb.id, containerConfig.Tty, containerConfig.Stdin, containerConfig.StdinOnce, sb.privileged, sb.trusted, containerInfo.Dir, created, containerImageConfig.Config.StopSignal)
if err != nil {
return nil, err
}
return container, nil
}
func (s *Server) setupSeccomp(specgen *generate.Generator, cname string, sbAnnotations map[string]string) error {
profile, ok := sbAnnotations["security.alpha.kubernetes.io/seccomp/container/"+cname]
if !ok {
profile, ok = sbAnnotations["security.alpha.kubernetes.io/seccomp/pod"]
if !ok {
// running w/o seccomp, aka unconfined
profile = seccompUnconfined
}
}
if !s.seccompEnabled {
if profile != seccompUnconfined {
return fmt.Errorf("seccomp is not enabled in your kernel, cannot run with a profile")
}
logrus.Warn("seccomp is not enabled in your kernel, running container without profile")
}
if profile == seccompUnconfined {
// running w/o seccomp, aka unconfined
specgen.Spec().Linux.Seccomp = nil
return nil
}
if profile == seccompRuntimeDefault {
return seccomp.LoadProfileFromStruct(s.seccompProfile, specgen)
}
if !strings.HasPrefix(profile, seccompLocalhostPrefix) {
return fmt.Errorf("unknown seccomp profile option: %q", profile)
}
//file, err := ioutil.ReadFile(filepath.Join(s.seccompProfileRoot, strings.TrimPrefix(profile, seccompLocalhostPrefix)))
//if err != nil {
//return err
//}
// TODO(runcom): setup from provided node's seccomp profile
// can't do this yet, see https://issues.k8s.io/36997
return nil
}
// getAppArmorProfileName gets the profile name for the given container.
func (s *Server) getAppArmorProfileName(annotations map[string]string, ctrName string) string {
profile := apparmor.GetProfileNameFromPodAnnotations(annotations, ctrName)
if profile == "" {
return ""
}
if profile == apparmor.ProfileRuntimeDefault {
// If the value is runtime/default, then return default profile.
return s.appArmorProfile
}
return strings.TrimPrefix(profile, apparmor.ProfileNamePrefix)
}
// openContainerFile opens a file inside a container rootfs safely
func openContainerFile(rootfs string, path string) (io.ReadCloser, error) {
fp, err := symlink.FollowSymlinkInScope(filepath.Join(rootfs, path), rootfs)
if err != nil {
return nil, err
}
return os.Open(fp)
}
// getUserInfo returns UID, GID and additional groups for specified user
// by looking them up in /etc/passwd and /etc/group
func getUserInfo(rootfs string, userName string) (uint32, uint32, []uint32, error) {
// We don't care if we can't open the file because
// not all images will have these files
passwdFile, err := openContainerFile(rootfs, "/etc/passwd")
if err != nil {
logrus.Warnf("Failed to open /etc/passwd: %v", err)
} else {
defer passwdFile.Close()
}
groupFile, err := openContainerFile(rootfs, "/etc/group")
if err != nil {
logrus.Warnf("Failed to open /etc/group: %v", err)
} else {
defer groupFile.Close()
}
execUser, err := user.GetExecUser(userName, nil, passwdFile, groupFile)
if err != nil {
return 0, 0, nil, err
}
uid := uint32(execUser.Uid)
gid := uint32(execUser.Gid)
var additionalGids []uint32
for _, g := range execUser.Sgids {
additionalGids = append(additionalGids, uint32(g))
}
return uid, gid, additionalGids, nil
}