Add support for IPoIB interfaces

- Add a new Link type, IPoIB, that exposes the following IPoIB attributes:
    * IFLA_IPOIB_PKEY
    * IFLA_IPOIB_MODE
    * IFLA_IPOIB_UMCAST
- Suppport Deserialize for IPoIB link attributes in LinkDeserialize()
- Support IPoIB attributes in LinkAdd()

link.go

@@ -918,6 +918,48 @@ func (xfrm *Xfrmi) Type() string {
 	return "xfrm"
 }
 
+// IPoIB interface
+
+type IPoIBMode uint16
+
+func (m *IPoIBMode) String() string {
+	str, ok := iPoIBModeToString[*m]
+	if !ok {
+		return fmt.Sprintf("mode(%d)", *m)
+	}
+	return str
+}
+
+const (
+	IPOIB_MODE_DATAGRAM = iota
+	IPOIB_MODE_CONNECTED
+)
+
+var iPoIBModeToString = map[IPoIBMode]string{
+	IPOIB_MODE_DATAGRAM:  "datagram",
+	IPOIB_MODE_CONNECTED: "connected",
+}
+
+var StringToIPoIBMode = map[string]IPoIBMode{
+	"datagram":  IPOIB_MODE_DATAGRAM,
+	"connected": IPOIB_MODE_CONNECTED,
+}
+
+type IPoIB struct {
+	LinkAttrs
+	Pkey   uint16
+	Mode   IPoIBMode
+	Umcast uint16
+}
+
+func (ipoib *IPoIB) Attrs() *LinkAttrs {
+	return &ipoib.LinkAttrs
+}
+
+func (ipoib *IPoIB) Type() string {
+	return "ipoib"
+}
+
 // iproute2 supported devices;
 // vlan | veth | vcan | dummy | ifb | macvlan | macvtap |
 // bridge | bond | ipoib | ip6tnl | ipip | sit | vxlan |

link_linux.go

@@ -1150,8 +1150,8 @@ func (h *Handle) linkModify(link Link, flags int) error {
 		native.PutUint32(b, uint32(base.ParentIndex))
 		data := nl.NewRtAttr(unix.IFLA_LINK, b)
 		req.AddData(data)
-	} else if link.Type() == "ipvlan" {
-		return fmt.Errorf("Can't create ipvlan link without ParentIndex")
+	} else if link.Type() == "ipvlan" || link.Type() == "ipoib" {
+		return fmt.Errorf("Can't create %s link without ParentIndex", link.Type())
 	}
 
 	nameData := nl.NewRtAttr(unix.IFLA_IFNAME, nl.ZeroTerminated(base.Name))
@@ -1278,6 +1278,8 @@ func (h *Handle) linkModify(link Link, flags int) error {
 		addGTPAttrs(link, linkInfo)
 	case *Xfrmi:
 		addXfrmiAttrs(link, linkInfo)
+	case *IPoIB:
+		addIPoIBAttrs(link, linkInfo)
 	}
 
 	req.AddData(linkInfo)
@@ -1533,6 +1535,8 @@ func LinkDeserialize(hdr *unix.NlMsghdr, m []byte) (Link, error) {
 						link = &Xfrmi{}
 					case "tun":
 						link = &Tuntap{}
+					case "ipoib":
+						link = &IPoIB{}
 					default:
 						link = &GenericLink{LinkType: linkType}
 					}
@@ -1578,6 +1582,8 @@ func LinkDeserialize(hdr *unix.NlMsghdr, m []byte) (Link, error) {
 						parseXfrmiData(link, data)
 					case "tun":
 						parseTuntapData(link, data)
+					case "ipoib":
+						parseIPoIBData(link, data)
 					}
 				}
 			}
@@ -2776,3 +2782,24 @@ func parseTuntapData(link Link, data []syscall.NetlinkRouteAttr) {
 		}
 	}
 }
+
+func parseIPoIBData(link Link, data []syscall.NetlinkRouteAttr) {
+	ipoib := link.(*IPoIB)
+	for _, datum := range data {
+		switch datum.Attr.Type {
+		case nl.IFLA_IPOIB_PKEY:
+			ipoib.Pkey = uint16(native.Uint16(datum.Value))
+		case nl.IFLA_IPOIB_MODE:
+			ipoib.Mode = IPoIBMode(native.Uint16(datum.Value))
+		case nl.IFLA_IPOIB_UMCAST:
+			ipoib.Umcast = uint16(native.Uint16(datum.Value))
+		}
+	}
+}
+
+func addIPoIBAttrs(ipoib *IPoIB, linkInfo *nl.RtAttr) {
+	data := linkInfo.AddRtAttr(nl.IFLA_INFO_DATA, nil)
+	data.AddRtAttr(nl.IFLA_IPOIB_PKEY, nl.Uint16Attr(uint16(ipoib.Pkey)))
+	data.AddRtAttr(nl.IFLA_IPOIB_MODE, nl.Uint16Attr(uint16(ipoib.Mode)))
+	data.AddRtAttr(nl.IFLA_IPOIB_UMCAST, nl.Uint16Attr(uint16(ipoib.Umcast)))
+}

nl/link_linux.go

@@ -596,3 +596,11 @@ const (
 	IFLA_TUN_NUM_DISABLED_QUEUES
 	IFLA_TUN_MAX = IFLA_TUN_NUM_DISABLED_QUEUES
 )
+
+const (
+	IFLA_IPOIB_UNSPEC = iota
+	IFLA_IPOIB_PKEY
+	IFLA_IPOIB_MODE
+	IFLA_IPOIB_UMCAST
+	IFLA_IPOIB_MAX = IFLA_IPOIB_UMCAST
+)