runc/libcontainer/message_linux.go

63 lines
1.5 KiB
Go

// +build linux
package libcontainer
import (
"syscall"
"github.com/vishvananda/netlink/nl"
)
// list of known message types we want to send to bootstrap program
// The number is randomly chosen to not conflict with known netlink types
const (
InitMsg uint16 = 62000
PidAttr uint16 = 27281
ConsolePathAttr uint16 = 27282
// When syscall.NLA_HDRLEN is in gccgo, take this out.
syscall_NLA_HDRLEN = (syscall.SizeofNlAttr + syscall.NLA_ALIGNTO - 1) & ^(syscall.NLA_ALIGNTO - 1)
)
type Int32msg struct {
Type uint16
Value uint32
}
// int32msg has the following representation
// | nlattr len | nlattr type |
// | uint32 value |
func (msg *Int32msg) Serialize() []byte {
buf := make([]byte, msg.Len())
native := nl.NativeEndian()
native.PutUint16(buf[0:2], uint16(msg.Len()))
native.PutUint16(buf[2:4], msg.Type)
native.PutUint32(buf[4:8], msg.Value)
return buf
}
func (msg *Int32msg) Len() int {
return syscall_NLA_HDRLEN + 4
}
// bytemsg has the following representation
// | nlattr len | nlattr type |
// | value | pad |
type Bytemsg struct {
Type uint16
Value []byte
}
func (msg *Bytemsg) Serialize() []byte {
l := msg.Len()
buf := make([]byte, (l+syscall.NLA_ALIGNTO-1) & ^(syscall.NLA_ALIGNTO-1))
native := nl.NativeEndian()
native.PutUint16(buf[0:2], uint16(l))
native.PutUint16(buf[2:4], msg.Type)
copy(buf[4:], msg.Value)
return buf
}
func (msg *Bytemsg) Len() int {
return syscall_NLA_HDRLEN + len(msg.Value) + 1 // null-terminated
}