Update vendored version of runc,buildah,containers/image

There is a compiler warning that has been fixed in the
upstream, so I figured we should update to fix.

Also vendor in latest buildah to get better support for running builds in rootless
mode.

Vendor in latest containers/image to allow daemon support to be pluggable.

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

Closes: #1169
Approved by: mheon

vendor/github.com/opencontainers/runc/libcontainer/user/lookup_unix.go

@@ -15,6 +15,76 @@ const (
 	unixGroupPath  = "/etc/group"
 )
 
+func lookupUser(username string) (User, error) {
+	return lookupUserFunc(func(u User) bool {
+		return u.Name == username
+	})
+}
+
+func lookupUid(uid int) (User, error) {
+	return lookupUserFunc(func(u User) bool {
+		return u.Uid == uid
+	})
+}
+
+func lookupUserFunc(filter func(u User) bool) (User, error) {
+	// Get operating system-specific passwd reader-closer.
+	passwd, err := GetPasswd()
+	if err != nil {
+		return User{}, err
+	}
+	defer passwd.Close()
+
+	// Get the users.
+	users, err := ParsePasswdFilter(passwd, filter)
+	if err != nil {
+		return User{}, err
+	}
+
+	// No user entries found.
+	if len(users) == 0 {
+		return User{}, ErrNoPasswdEntries
+	}
+
+	// Assume the first entry is the "correct" one.
+	return users[0], nil
+}
+
+func lookupGroup(groupname string) (Group, error) {
+	return lookupGroupFunc(func(g Group) bool {
+		return g.Name == groupname
+	})
+}
+
+func lookupGid(gid int) (Group, error) {
+	return lookupGroupFunc(func(g Group) bool {
+		return g.Gid == gid
+	})
+}
+
+func lookupGroupFunc(filter func(g Group) bool) (Group, error) {
+	// Get operating system-specific group reader-closer.
+	group, err := GetGroup()
+	if err != nil {
+		return Group{}, err
+	}
+	defer group.Close()
+
+	// Get the users.
+	groups, err := ParseGroupFilter(group, filter)
+	if err != nil {
+		return Group{}, err
+	}
+
+	// No user entries found.
+	if len(groups) == 0 {
+		return Group{}, ErrNoGroupEntries
+	}
+
+	// Assume the first entry is the "correct" one.
+	return groups[0], nil
+}
+
 func GetPasswdPath() (string, error) {
 	return unixPasswdPath, nil
 }
@@ -44,3 +114,29 @@ func CurrentUser() (User, error) {
 func CurrentGroup() (Group, error) {
 	return LookupGid(unix.Getgid())
 }
+
+func CurrentUserSubUIDs() ([]SubID, error) {
+	u, err := CurrentUser()
+	if err != nil {
+		return nil, err
+	}
+	return ParseSubIDFileFilter("/etc/subuid",
+		func(entry SubID) bool { return entry.Name == u.Name })
+}
+
+func CurrentGroupSubGIDs() ([]SubID, error) {
+	g, err := CurrentGroup()
+	if err != nil {
+		return nil, err
+	}
+	return ParseSubIDFileFilter("/etc/subgid",
+		func(entry SubID) bool { return entry.Name == g.Name })
+}
+
+func CurrentProcessUIDMap() ([]IDMap, error) {
+	return ParseIDMapFile("/proc/self/uid_map")
+}
+
+func CurrentProcessGIDMap() ([]IDMap, error) {
+	return ParseIDMapFile("/proc/self/gid_map")
+}