runc/libcontainer/keys/keyctl.go

51 lines
1.1 KiB
Go

// +build linux
package keys
import (
"fmt"
"strconv"
"strings"
"golang.org/x/sys/unix"
)
type KeySerial uint32
func JoinSessionKeyring(name string) (KeySerial, error) {
sessKeyId, err := unix.KeyctlJoinSessionKeyring(name)
if err != nil {
return 0, fmt.Errorf("could not create session key: %v", err)
}
return KeySerial(sessKeyId), nil
}
// ModKeyringPerm modifies permissions on a keyring by reading the current permissions,
// anding the bits with the given mask (clearing permissions) and setting
// additional permission bits
func ModKeyringPerm(ringId KeySerial, mask, setbits uint32) error {
dest, err := unix.KeyctlString(unix.KEYCTL_DESCRIBE, int(ringId))
if err != nil {
return err
}
res := strings.Split(dest, ";")
if len(res) < 5 {
return fmt.Errorf("Destination buffer for key description is too small")
}
// parse permissions
perm64, err := strconv.ParseUint(res[3], 16, 32)
if err != nil {
return err
}
perm := (uint32(perm64) & mask) | setbits
if err := unix.KeyctlSetperm(int(ringId), perm); err != nil {
return err
}
return nil
}