Add user namespace (mapping) support to the Docker engine

Adds support for the daemon to handle user namespace maps as a
per-daemon setting.

Support for handling uid/gid mapping is added to the builder,
archive/unarchive packages and functions, all graphdrivers (except
Windows), and the test suite is updated to handle user namespace daemon
rootgraph changes.

Docker-DCO-1.1-Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com> (github: estesp)
This commit is contained in:
Phil Estes 2015-10-08 11:51:41 -04:00
parent 5e8012caca
commit e118299052
14 changed files with 262 additions and 27 deletions

View file

@ -11,6 +11,7 @@ import (
"strings"
"github.com/Sirupsen/logrus"
"github.com/docker/docker/pkg/idtools"
"github.com/docker/docker/pkg/pools"
"github.com/docker/docker/pkg/system"
)
@ -18,16 +19,23 @@ import (
// UnpackLayer unpack `layer` to a `dest`. The stream `layer` can be
// compressed or uncompressed.
// Returns the size in bytes of the contents of the layer.
func UnpackLayer(dest string, layer Reader) (size int64, err error) {
func UnpackLayer(dest string, layer Reader, options *TarOptions) (size int64, err error) {
tr := tar.NewReader(layer)
trBuf := pools.BufioReader32KPool.Get(tr)
defer pools.BufioReader32KPool.Put(trBuf)
var dirs []*tar.Header
remappedRootUID, remappedRootGID, err := idtools.GetRootUIDGID(options.UIDMaps, options.GIDMaps)
if err != nil {
return 0, err
}
aufsTempdir := ""
aufsHardlinks := make(map[string]*tar.Header)
if options == nil {
options = &TarOptions{}
}
// Iterate through the files in the archive.
for {
hdr, err := tr.Next()
@ -169,6 +177,27 @@ func UnpackLayer(dest string, layer Reader) (size int64, err error) {
srcData = tmpFile
}
// if the options contain a uid & gid maps, convert header uid/gid
// entries using the maps such that lchown sets the proper mapped
// uid/gid after writing the file. We only perform this mapping if
// the file isn't already owned by the remapped root UID or GID, as
// that specific uid/gid has no mapping from container -> host, and
// those files already have the proper ownership for inside the
// container.
if srcHdr.Uid != remappedRootUID {
xUID, err := idtools.ToHost(srcHdr.Uid, options.UIDMaps)
if err != nil {
return 0, err
}
srcHdr.Uid = xUID
}
if srcHdr.Gid != remappedRootGID {
xGID, err := idtools.ToHost(srcHdr.Gid, options.GIDMaps)
if err != nil {
return 0, err
}
srcHdr.Gid = xGID
}
if err := createTarFile(path, dest, srcHdr, srcData, true, nil); err != nil {
return 0, err
}
@ -196,19 +225,19 @@ func UnpackLayer(dest string, layer Reader) (size int64, err error) {
// compressed or uncompressed.
// Returns the size in bytes of the contents of the layer.
func ApplyLayer(dest string, layer Reader) (int64, error) {
return applyLayerHandler(dest, layer, true)
return applyLayerHandler(dest, layer, &TarOptions{}, true)
}
// ApplyUncompressedLayer parses a diff in the standard layer format from
// `layer`, and applies it to the directory `dest`. The stream `layer`
// can only be uncompressed.
// Returns the size in bytes of the contents of the layer.
func ApplyUncompressedLayer(dest string, layer Reader) (int64, error) {
return applyLayerHandler(dest, layer, false)
func ApplyUncompressedLayer(dest string, layer Reader, options *TarOptions) (int64, error) {
return applyLayerHandler(dest, layer, options, false)
}
// do the bulk load of ApplyLayer, but allow for not calling DecompressStream
func applyLayerHandler(dest string, layer Reader, decompress bool) (int64, error) {
func applyLayerHandler(dest string, layer Reader, options *TarOptions, decompress bool) (int64, error) {
dest = filepath.Clean(dest)
// We need to be able to set any perms
@ -224,5 +253,5 @@ func applyLayerHandler(dest string, layer Reader, decompress bool) (int64, error
return 0, err
}
}
return UnpackLayer(dest, layer)
return UnpackLayer(dest, layer, options)
}