Implement create veth

Docker-DCO-1.1-Signed-off-by: Guillaume J. Charmes <guillaume.charmes@docker.com> (github: creack)
This commit is contained in:
Guillaume J. Charmes 2014-02-12 04:09:56 -08:00
parent a37785b64f
commit 000df04348

View file

@ -142,29 +142,61 @@ func rtaAlignOf(attrlen int) int {
type RtAttr struct {
syscall.RtAttr
Data []byte
Data []byte
children []*RtAttr
prefix int
}
func newRtAttr(attrType int, data []byte) *RtAttr {
attr := &RtAttr{}
attr := &RtAttr{
children: []*RtAttr{},
}
attr.Type = uint16(attrType)
attr.Data = data
return attr
}
func (attr *RtAttr) ToWireFormat() []byte {
func newRtAttrChild(parent *RtAttr, attrType int, data []byte) *RtAttr {
attr := newRtAttr(attrType, data)
parent.children = append(parent.children, attr)
return attr
}
func (a *RtAttr) length() int {
l := 0
for _, child := range a.children {
l += child.length() + syscall.SizeofRtAttr + child.prefix
}
if l == 0 {
l++
}
return rtaAlignOf(l + len(a.Data))
}
func (a *RtAttr) ToWireFormat() []byte {
native := nativeEndian()
len := syscall.SizeofRtAttr + len(attr.Data)
b := make([]byte, rtaAlignOf(len))
native.PutUint16(b[0:2], uint16(len))
native.PutUint16(b[2:4], attr.Type)
for i, d := range attr.Data {
b[4+i] = d
length := a.length()
buf := make([]byte, rtaAlignOf(length+syscall.SizeofRtAttr))
if a.Data != nil {
copy(buf[4:], a.Data)
} else {
next := 4
for _, child := range a.children {
childBuf := child.ToWireFormat()
copy(buf[next+child.prefix:], childBuf)
next += rtaAlignOf(len(childBuf))
}
}
return b
if l := uint16(rtaAlignOf(length)); l != 0 {
native.PutUint16(buf[0:2], l+1)
}
native.PutUint16(buf[2:4], a.Type)
return buf
}
type NetlinkRequest struct {
@ -501,12 +533,7 @@ func NetworkLinkAddIp(iface *net.Interface, ip net.IP, ipNet *net.IPNet) error {
}
func zeroTerminated(s string) []byte {
bytes := make([]byte, len(s)+1)
for i := 0; i < len(s); i++ {
bytes[i] = s[i]
}
bytes[len(s)] = 0
return bytes
return []byte(s + "\000")
}
func nonZeroTerminated(s string) []byte {
@ -697,24 +724,19 @@ func NetworkCreateVethPair(name1, name2 string) error {
msg := newIfInfomsg(syscall.AF_UNSPEC)
wb.AddData(msg)
kindData := newRtAttr(IFLA_INFO_KIND, nonZeroTerminated("veth"))
info := newRtAttr(syscall.IFLA_LINKINFO, kindData.ToWireFormat())
// wb.AddData(info)
peerName := newRtAttr(syscall.IFLA_IFNAME, nonZeroTerminated(name2))
peer := newRtAttr(VETH_PEER, peerName.ToWireFormat())
// wb.AddData(peer)
b := []byte{}
b = append(b, peer.ToWireFormat()...)
b = append(b, info.ToWireFormat()...)
infoData := newRtAttr(IFLA_INFO_DATA, b)
wb.AddData(infoData)
nameData := newRtAttr(syscall.IFLA_IFNAME, zeroTerminated(name1))
wb.AddData(nameData)
nest1 := newRtAttr(syscall.IFLA_LINKINFO, nil)
newRtAttrChild(nest1, IFLA_INFO_KIND, zeroTerminated("veth"))
nest2 := newRtAttrChild(nest1, IFLA_INFO_DATA, nil)
nest3 := newRtAttrChild(nest2, VETH_PEER, nil)
last := newRtAttrChild(nest3, syscall.IFLA_IFNAME, zeroTerminated(name2))
last.prefix = syscall.SizeofIfInfomsg
wb.AddData(nest1)
if err := s.Send(wb); err != nil {
return err
}