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Diffstat (limited to 'libpod/container_internal_linux.go')
-rw-r--r--libpod/container_internal_linux.go235
1 files changed, 235 insertions, 0 deletions
diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go
index 66c7e8a04..86e3db4e3 100644
--- a/libpod/container_internal_linux.go
+++ b/libpod/container_internal_linux.go
@@ -11,6 +11,7 @@ import (
"os"
"path"
"path/filepath"
+ "strconv"
"strings"
"sync"
"syscall"
@@ -21,8 +22,11 @@ import (
crioAnnotations "github.com/containers/libpod/pkg/annotations"
"github.com/containers/libpod/pkg/criu"
"github.com/containers/libpod/pkg/lookup"
+ "github.com/containers/libpod/pkg/resolvconf"
"github.com/containers/libpod/pkg/rootless"
+ "github.com/containers/libpod/pkg/secrets"
"github.com/containers/storage/pkg/idtools"
+ "github.com/opencontainers/runc/libcontainer/user"
spec "github.com/opencontainers/runtime-spec/specs-go"
"github.com/opencontainers/runtime-tools/generate"
"github.com/opencontainers/selinux/go-selinux/label"
@@ -132,6 +136,9 @@ func (c *Container) prepare() (err error) {
// cleanupNetwork unmounts and cleans up the container's network
func (c *Container) cleanupNetwork() error {
+ if c.NetworkDisabled() {
+ return nil
+ }
if c.state.NetNS == nil {
logrus.Debugf("Network is already cleaned up, skipping...")
return nil
@@ -169,6 +176,11 @@ func (c *Container) generateSpec(ctx context.Context) (*spec.Spec, error) {
g.AddOrReplaceLinuxNamespace(spec.NetworkNamespace, c.state.NetNS.Path())
}
}
+
+ if err := c.makeBindMounts(); err != nil {
+ return nil, err
+ }
+
// Check if the spec file mounts contain the label Relabel flags z or Z.
// If they do, relabel the source directory and then remove the option.
for _, m := range g.Mounts() {
@@ -591,3 +603,226 @@ func (c *Container) restore(ctx context.Context, keep bool) (err error) {
return c.save()
}
+
+// Make standard bind mounts to include in the container
+func (c *Container) makeBindMounts() error {
+ if err := os.Chown(c.state.RunDir, c.RootUID(), c.RootGID()); err != nil {
+ return errors.Wrapf(err, "cannot chown run directory %s", c.state.RunDir)
+ }
+
+ if c.state.BindMounts == nil {
+ c.state.BindMounts = make(map[string]string)
+ }
+
+ if !c.NetworkDisabled() {
+ // Make /etc/resolv.conf
+ if _, ok := c.state.BindMounts["/etc/resolv.conf"]; ok {
+ // If it already exists, delete so we can recreate
+ delete(c.state.BindMounts, "/etc/resolv.conf")
+ }
+ newResolv, err := c.generateResolvConf()
+ if err != nil {
+ return errors.Wrapf(err, "error creating resolv.conf for container %s", c.ID())
+ }
+ c.state.BindMounts["/etc/resolv.conf"] = newResolv
+
+ // Make /etc/hosts
+ if _, ok := c.state.BindMounts["/etc/hosts"]; ok {
+ // If it already exists, delete so we can recreate
+ delete(c.state.BindMounts, "/etc/hosts")
+ }
+ newHosts, err := c.generateHosts()
+ if err != nil {
+ return errors.Wrapf(err, "error creating hosts file for container %s", c.ID())
+ }
+ c.state.BindMounts["/etc/hosts"] = newHosts
+
+ }
+
+ // SHM is always added when we mount the container
+ c.state.BindMounts["/dev/shm"] = c.config.ShmDir
+
+ newPasswd, err := c.generatePasswd()
+ if err != nil {
+ return errors.Wrapf(err, "error creating temporary passwd file for container %s", c.ID())
+ }
+ if newPasswd != "" {
+ // Make /etc/passwd
+ if _, ok := c.state.BindMounts["/etc/passwd"]; ok {
+ // If it already exists, delete so we can recreate
+ delete(c.state.BindMounts, "/etc/passwd")
+ }
+ logrus.Debugf("adding entry to /etc/passwd for non existent default user")
+ c.state.BindMounts["/etc/passwd"] = newPasswd
+ }
+
+ // Make /etc/hostname
+ // This should never change, so no need to recreate if it exists
+ if _, ok := c.state.BindMounts["/etc/hostname"]; !ok {
+ hostnamePath, err := c.writeStringToRundir("hostname", c.Hostname())
+ if err != nil {
+ return errors.Wrapf(err, "error creating hostname file for container %s", c.ID())
+ }
+ c.state.BindMounts["/etc/hostname"] = hostnamePath
+ }
+
+ // Make .containerenv
+ // Empty file, so no need to recreate if it exists
+ if _, ok := c.state.BindMounts["/run/.containerenv"]; !ok {
+ // Empty string for now, but we may consider populating this later
+ containerenvPath, err := c.writeStringToRundir(".containerenv", "")
+ if err != nil {
+ return errors.Wrapf(err, "error creating containerenv file for container %s", c.ID())
+ }
+ c.state.BindMounts["/run/.containerenv"] = containerenvPath
+ }
+
+ // Add Secret Mounts
+ secretMounts := secrets.SecretMountsWithUIDGID(c.config.MountLabel, c.state.RunDir, c.runtime.config.DefaultMountsFile, c.state.DestinationRunDir, c.RootUID(), c.RootGID())
+ for _, mount := range secretMounts {
+ if _, ok := c.state.BindMounts[mount.Destination]; !ok {
+ c.state.BindMounts[mount.Destination] = mount.Source
+ }
+ }
+
+ return nil
+}
+
+// generateResolvConf generates a containers resolv.conf
+func (c *Container) generateResolvConf() (string, error) {
+ // Determine the endpoint for resolv.conf in case it is a symlink
+ resolvPath, err := filepath.EvalSymlinks("/etc/resolv.conf")
+ if err != nil {
+ return "", err
+ }
+
+ contents, err := ioutil.ReadFile(resolvPath)
+ if err != nil {
+ return "", errors.Wrapf(err, "unable to read %s", resolvPath)
+ }
+
+ // Process the file to remove localhost nameservers
+ // TODO: set ipv6 enable bool more sanely
+ resolv, err := resolvconf.FilterResolvDNS(contents, true)
+ if err != nil {
+ return "", errors.Wrapf(err, "error parsing host resolv.conf")
+ }
+
+ // Make a new resolv.conf
+ nameservers := resolvconf.GetNameservers(resolv.Content)
+ if len(c.config.DNSServer) > 0 {
+ // We store DNS servers as net.IP, so need to convert to string
+ nameservers = []string{}
+ for _, server := range c.config.DNSServer {
+ nameservers = append(nameservers, server.String())
+ }
+ }
+
+ search := resolvconf.GetSearchDomains(resolv.Content)
+ if len(c.config.DNSSearch) > 0 {
+ search = c.config.DNSSearch
+ }
+
+ options := resolvconf.GetOptions(resolv.Content)
+ if len(c.config.DNSOption) > 0 {
+ options = c.config.DNSOption
+ }
+
+ destPath := filepath.Join(c.state.RunDir, "resolv.conf")
+
+ if err := os.Remove(destPath); err != nil && !os.IsNotExist(err) {
+ return "", errors.Wrapf(err, "error removing resolv.conf for container %s", c.ID())
+ }
+
+ // Build resolv.conf
+ if _, err = resolvconf.Build(destPath, nameservers, search, options); err != nil {
+ return "", errors.Wrapf(err, "error building resolv.conf for container %s")
+ }
+
+ // Relabel resolv.conf for the container
+ if err := label.Relabel(destPath, c.config.MountLabel, false); err != nil {
+ return "", err
+ }
+
+ return filepath.Join(c.state.DestinationRunDir, "resolv.conf"), nil
+}
+
+// generateHosts creates a containers hosts file
+func (c *Container) generateHosts() (string, error) {
+ orig, err := ioutil.ReadFile("/etc/hosts")
+ if err != nil {
+ return "", errors.Wrapf(err, "unable to read /etc/hosts")
+ }
+ hosts := string(orig)
+ if len(c.config.HostAdd) > 0 {
+ for _, host := range c.config.HostAdd {
+ // the host format has already been verified at this point
+ fields := strings.SplitN(host, ":", 2)
+ hosts += fmt.Sprintf("%s %s\n", fields[1], fields[0])
+ }
+ }
+ if len(c.state.NetworkStatus) > 0 && len(c.state.NetworkStatus[0].IPs) > 0 {
+ ipAddress := strings.Split(c.state.NetworkStatus[0].IPs[0].Address.String(), "/")[0]
+ hosts += fmt.Sprintf("%s\t%s\n", ipAddress, c.Hostname())
+ }
+ return c.writeStringToRundir("hosts", hosts)
+}
+
+// generatePasswd generates a container specific passwd file,
+// iff g.config.User is a number
+func (c *Container) generatePasswd() (string, error) {
+ var (
+ groupspec string
+ group *user.Group
+ gid int
+ )
+ if c.config.User == "" {
+ return "", nil
+ }
+ spec := strings.SplitN(c.config.User, ":", 2)
+ userspec := spec[0]
+ if len(spec) > 1 {
+ groupspec = spec[1]
+ }
+ // If a non numeric User, then don't generate passwd
+ uid, err := strconv.ParseUint(userspec, 10, 32)
+ if err != nil {
+ return "", nil
+ }
+ // Lookup the user to see if it exists in the container image
+ _, err = lookup.GetUser(c.state.Mountpoint, userspec)
+ if err != nil && err != user.ErrNoPasswdEntries {
+ return "", err
+ }
+ if err == nil {
+ return "", nil
+ }
+ if groupspec != "" {
+ if !c.state.Mounted {
+ return "", errors.Wrapf(ErrCtrStateInvalid, "container %s must be mounted in order to translate group field for passwd record", c.ID())
+ }
+ group, err = lookup.GetGroup(c.state.Mountpoint, groupspec)
+ if err != nil {
+ if err == user.ErrNoGroupEntries {
+ return "", errors.Wrapf(err, "unable to get gid %s from group file", groupspec)
+ }
+ return "", err
+ }
+ gid = group.Gid
+ }
+ originPasswdFile := filepath.Join(c.state.Mountpoint, "/etc/passwd")
+ orig, err := ioutil.ReadFile(originPasswdFile)
+ if err != nil && !os.IsNotExist(err) {
+ return "", errors.Wrapf(err, "unable to read passwd file %s", originPasswdFile)
+ }
+
+ pwd := fmt.Sprintf("%s%d:x:%d:%d:container user:%s:/bin/sh\n", orig, uid, uid, gid, c.WorkingDir())
+ passwdFile, err := c.writeStringToRundir("passwd", pwd)
+ if err != nil {
+ return "", errors.Wrapf(err, "failed to create temporary passwd file")
+ }
+ if os.Chmod(passwdFile, 0644); err != nil {
+ return "", err
+ }
+ return passwdFile, nil
+}