Vendor in latest containers storage

We want to get support into skopeo for handling
override_kernel_checks so that we can use overlay
backend on RHEL.

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

vendor/github.com/containers/storage/pkg/idtools/idtools.go

@@ -37,49 +37,56 @@ const (
 // MkdirAllAs creates a directory (include any along the path) and then modifies
 // ownership to the requested uid/gid.  If the directory already exists, this
 // function will still change ownership to the requested uid/gid pair.
+// Deprecated: Use MkdirAllAndChown
 func MkdirAllAs(path string, mode os.FileMode, ownerUID, ownerGID int) error {
 	return mkdirAs(path, mode, ownerUID, ownerGID, true, true)
 }
 
-// MkdirAllNewAs creates a directory (include any along the path) and then modifies
-// ownership ONLY of newly created directories to the requested uid/gid. If the
-// directories along the path exist, no change of ownership will be performed
-func MkdirAllNewAs(path string, mode os.FileMode, ownerUID, ownerGID int) error {
-	return mkdirAs(path, mode, ownerUID, ownerGID, true, false)
-}
-
 // MkdirAs creates a directory and then modifies ownership to the requested uid/gid.
 // If the directory already exists, this function still changes ownership
+// Deprecated: Use MkdirAndChown with a IDPair
 func MkdirAs(path string, mode os.FileMode, ownerUID, ownerGID int) error {
 	return mkdirAs(path, mode, ownerUID, ownerGID, false, true)
 }
 
+// MkdirAllAndChown creates a directory (include any along the path) and then modifies
+// ownership to the requested uid/gid.  If the directory already exists, this
+// function will still change ownership to the requested uid/gid pair.
+func MkdirAllAndChown(path string, mode os.FileMode, ids IDPair) error {
+	return mkdirAs(path, mode, ids.UID, ids.GID, true, true)
+}
+
+// MkdirAndChown creates a directory and then modifies ownership to the requested uid/gid.
+// If the directory already exists, this function still changes ownership
+func MkdirAndChown(path string, mode os.FileMode, ids IDPair) error {
+	return mkdirAs(path, mode, ids.UID, ids.GID, false, true)
+}
+
+// MkdirAllAndChownNew creates a directory (include any along the path) and then modifies
+// ownership ONLY of newly created directories to the requested uid/gid. If the
+// directories along the path exist, no change of ownership will be performed
+func MkdirAllAndChownNew(path string, mode os.FileMode, ids IDPair) error {
+	return mkdirAs(path, mode, ids.UID, ids.GID, true, false)
+}
+
 // GetRootUIDGID retrieves the remapped root uid/gid pair from the set of maps.
 // If the maps are empty, then the root uid/gid will default to "real" 0/0
 func GetRootUIDGID(uidMap, gidMap []IDMap) (int, int, error) {
-	var uid, gid int
-
-	if uidMap != nil {
-		xUID, err := ToHost(0, uidMap)
-		if err != nil {
-			return -1, -1, err
-		}
-		uid = xUID
+	uid, err := toHost(0, uidMap)
+	if err != nil {
+		return -1, -1, err
 	}
-	if gidMap != nil {
-		xGID, err := ToHost(0, gidMap)
-		if err != nil {
-			return -1, -1, err
-		}
-		gid = xGID
+	gid, err := toHost(0, gidMap)
+	if err != nil {
+		return -1, -1, err
 	}
 	return uid, gid, nil
 }
 
-// ToContainer takes an id mapping, and uses it to translate a
+// toContainer takes an id mapping, and uses it to translate a
 // host ID to the remapped ID. If no map is provided, then the translation
 // assumes a 1-to-1 mapping and returns the passed in id
-func ToContainer(hostID int, idMap []IDMap) (int, error) {
+func toContainer(hostID int, idMap []IDMap) (int, error) {
 	if idMap == nil {
 		return hostID, nil
 	}
@@ -92,10 +99,10 @@ func ToContainer(hostID int, idMap []IDMap) (int, error) {
 	return -1, fmt.Errorf("Host ID %d cannot be mapped to a container ID", hostID)
 }
 
-// ToHost takes an id mapping and a remapped ID, and translates the
+// toHost takes an id mapping and a remapped ID, and translates the
 // ID to the mapped host ID. If no map is provided, then the translation
 // assumes a 1-to-1 mapping and returns the passed in id #
-func ToHost(contID int, idMap []IDMap) (int, error) {
+func toHost(contID int, idMap []IDMap) (int, error) {
 	if idMap == nil {
 		return contID, nil
 	}
@@ -108,26 +115,101 @@ func ToHost(contID int, idMap []IDMap) (int, error) {
 	return -1, fmt.Errorf("Container ID %d cannot be mapped to a host ID", contID)
 }
 
-// CreateIDMappings takes a requested user and group name and
+// IDPair is a UID and GID pair
+type IDPair struct {
+	UID int
+	GID int
+}
+
+// IDMappings contains a mappings of UIDs and GIDs
+type IDMappings struct {
+	uids []IDMap
+	gids []IDMap
+}
+
+// NewIDMappings takes a requested user and group name and
 // using the data from /etc/sub{uid,gid} ranges, creates the
 // proper uid and gid remapping ranges for that user/group pair
-func CreateIDMappings(username, groupname string) ([]IDMap, []IDMap, error) {
+func NewIDMappings(username, groupname string) (*IDMappings, error) {
 	subuidRanges, err := parseSubuid(username)
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 	subgidRanges, err := parseSubgid(groupname)
 	if err != nil {
-		return nil, nil, err
+		return nil, err
 	}
 	if len(subuidRanges) == 0 {
-		return nil, nil, fmt.Errorf("No subuid ranges found for user %q", username)
+		return nil, fmt.Errorf("No subuid ranges found for user %q", username)
 	}
 	if len(subgidRanges) == 0 {
-		return nil, nil, fmt.Errorf("No subgid ranges found for group %q", groupname)
+		return nil, fmt.Errorf("No subgid ranges found for group %q", groupname)
 	}
 
-	return createIDMap(subuidRanges), createIDMap(subgidRanges), nil
+	return &IDMappings{
+		uids: createIDMap(subuidRanges),
+		gids: createIDMap(subgidRanges),
+	}, nil
+}
+
+// NewIDMappingsFromMaps creates a new mapping from two slices
+// Deprecated: this is a temporary shim while transitioning to IDMapping
+func NewIDMappingsFromMaps(uids []IDMap, gids []IDMap) *IDMappings {
+	return &IDMappings{uids: uids, gids: gids}
+}
+
+// RootPair returns a uid and gid pair for the root user. The error is ignored
+// because a root user always exists, and the defaults are correct when the uid
+// and gid maps are empty.
+func (i *IDMappings) RootPair() IDPair {
+	uid, gid, _ := GetRootUIDGID(i.uids, i.gids)
+	return IDPair{UID: uid, GID: gid}
+}
+
+// ToHost returns the host UID and GID for the container uid, gid.
+// Remapping is only performed if the ids aren't already the remapped root ids
+func (i *IDMappings) ToHost(pair IDPair) (IDPair, error) {
+	var err error
+	target := i.RootPair()
+
+	if pair.UID != target.UID {
+		target.UID, err = toHost(pair.UID, i.uids)
+		if err != nil {
+			return target, err
+		}
+	}
+
+	if pair.GID != target.GID {
+		target.GID, err = toHost(pair.GID, i.gids)
+	}
+	return target, err
+}
+
+// ToContainer returns the container UID and GID for the host uid and gid
+func (i *IDMappings) ToContainer(pair IDPair) (int, int, error) {
+	uid, err := toContainer(pair.UID, i.uids)
+	if err != nil {
+		return -1, -1, err
+	}
+	gid, err := toContainer(pair.GID, i.gids)
+	return uid, gid, err
+}
+
+// Empty returns true if there are no id mappings
+func (i *IDMappings) Empty() bool {
+	return len(i.uids) == 0 && len(i.gids) == 0
+}
+
+// UIDs return the UID mapping
+// TODO: remove this once everything has been refactored to use pairs
+func (i *IDMappings) UIDs() []IDMap {
+	return i.uids
+}
+
+// GIDs return the UID mapping
+// TODO: remove this once everything has been refactored to use pairs
+func (i *IDMappings) GIDs() []IDMap {
+	return i.gids
 }
 
 func createIDMap(subidRanges ranges) []IDMap {