Merge pull request #1482 from tklauser/x-sys-unix-keyctl

Use keyctl wrappers from x/sys/unix

libcontainer/keys/keyctl.go

@@ -6,31 +6,16 @@ import (
 	"fmt"
 	"strconv"
 	"strings"
-	"unsafe"
 
 	"golang.org/x/sys/unix"
 )
 
-const KEYCTL_JOIN_SESSION_KEYRING = 1
-const KEYCTL_SETPERM = 5
-const KEYCTL_DESCRIBE = 6
-
 type KeySerial uint32
 
 func JoinSessionKeyring(name string) (KeySerial, error) {
-	var _name *byte
-	var err error
-
-	if len(name) > 0 {
-		_name, err = unix.BytePtrFromString(name)
-		if err != nil {
-			return KeySerial(0), err
-		}
-	}
-
-	sessKeyId, _, errn := unix.Syscall(unix.SYS_KEYCTL, KEYCTL_JOIN_SESSION_KEYRING, uintptr(unsafe.Pointer(_name)), 0)
-	if errn != 0 {
-		return 0, fmt.Errorf("could not create session key: %v", errn)
+	sessKeyId, err := unix.KeyctlJoinSessionKeyring(name)
+	if err != nil {
+		return 0, fmt.Errorf("could not create session key: %v", err)
 	}
 	return KeySerial(sessKeyId), nil
 }
@@ -39,10 +24,8 @@ func JoinSessionKeyring(name string) (KeySerial, error) {
 // anding the bits with the given mask (clearing permissions) and setting
 // additional permission bits
 func ModKeyringPerm(ringId KeySerial, mask, setbits uint32) error {
-	dest := make([]byte, 1024)
-	destBytes := unsafe.Pointer(&dest[0])
-
-	if _, _, err := unix.Syscall6(unix.SYS_KEYCTL, uintptr(KEYCTL_DESCRIBE), uintptr(ringId), uintptr(destBytes), uintptr(len(dest)), 0, 0); err != 0 {
+	dest, err := unix.KeyctlString(unix.KEYCTL_DESCRIBE, int(ringId))
+	if err != nil {
 		return err
 	}
 
@@ -59,7 +42,7 @@ func ModKeyringPerm(ringId KeySerial, mask, setbits uint32) error {
 
 	perm := (uint32(perm64) & mask) | setbits
 
-	if _, _, err := unix.Syscall(unix.SYS_KEYCTL, uintptr(KEYCTL_SETPERM), uintptr(ringId), uintptr(perm)); err != 0 {
+	if err := unix.KeyctlSetperm(int(ringId), perm); err != nil {
 		return err
 	}