From b7b7ca86324cca6ec2f2756e4d562533e077bbee Mon Sep 17 00:00:00 2001
From: Hu Jun <hujun.work@gmail.com>
Date: Sun, 24 Dec 2023 13:38:42 -0800
Subject: [PATCH] add group_fwd_mask support for bridge and bridge port

---
 bridge_linux_test.go | 35 +++++++++++++++++++++++++++++++++++
 link.go              |  1 +
 link_linux.go        | 23 +++++++++++++++++++++--
 3 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/bridge_linux_test.go b/bridge_linux_test.go
index 6fb45b1..710a01b 100644
--- a/bridge_linux_test.go
+++ b/bridge_linux_test.go
@@ -78,3 +78,38 @@ func TestBridgeVlan(t *testing.T) {
 		}
 	}
 }
+
+func TestBridgeGroupFwdMask(t *testing.T) {
+	minKernelRequired(t, 4, 15) //minimal release for per-port group_fwd_mask
+	tearDown := setUpNetlinkTest(t)
+	defer tearDown()
+	if err := remountSysfs(); err != nil {
+		t.Fatal(err)
+	}
+	bridgeName := "foo"
+	var mask uint16 = 0xfff0
+	bridge := &Bridge{LinkAttrs: LinkAttrs{Name: bridgeName}, GroupFwdMask: &mask}
+	if err := LinkAdd(bridge); err != nil {
+		t.Fatal(err)
+	}
+	brlink, err := LinkByName(bridgeName)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if *(brlink.(*Bridge).GroupFwdMask) != mask {
+		t.Fatalf("created bridge has group_fwd_mask value %x, different from expected %x",
+			*(brlink.(*Bridge).GroupFwdMask), mask)
+	}
+	dummyName := "dm1"
+	dummy := &Dummy{LinkAttrs: LinkAttrs{Name: dummyName, MasterIndex: brlink.Attrs().Index}}
+	if err := LinkAdd(dummy); err != nil {
+		t.Fatal(err)
+	}
+	dmLink, err := LinkByName(dummyName)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err = LinkSetBRSlaveGroupFwdMask(dmLink, mask); err != nil {
+		t.Fatal(err)
+	}
+}
diff --git a/link.go b/link.go
index 5d618ad..260542e 100644
--- a/link.go
+++ b/link.go
@@ -274,6 +274,7 @@ type Bridge struct {
 	HelloTime         *uint32
 	VlanFiltering     *bool
 	VlanDefaultPVID   *uint16
+	GroupFwdMask      *uint16
 }
 
 func (bridge *Bridge) Attrs() *LinkAttrs {
diff --git a/link_linux.go b/link_linux.go
index 505d92d..3559484 100644
--- a/link_linux.go
+++ b/link_linux.go
@@ -2494,6 +2494,16 @@ func (h *Handle) LinkSetGuard(link Link, mode bool) error {
 	return h.setProtinfoAttr(link, mode, nl.IFLA_BRPORT_GUARD)
 }
 
+// LinkSetBRSlaveGroupFwdMask set the group_fwd_mask of a bridge slave interface
+func LinkSetBRSlaveGroupFwdMask(link Link, mask uint16) error {
+	return pkgHandle.LinkSetBRSlaveGroupFwdMask(link, mask)
+}
+
+// LinkSetBRSlaveGroupFwdMask set the group_fwd_mask of a bridge slave interface
+func (h *Handle) LinkSetBRSlaveGroupFwdMask(link Link, mask uint16) error {
+	return h.setProtinfoAttrRawVal(link, nl.Uint16Attr(mask), nl.IFLA_BRPORT_GROUP_FWD_MASK)
+}
+
 func LinkSetFastLeave(link Link, mode bool) error {
 	return pkgHandle.LinkSetFastLeave(link, mode)
 }
@@ -2558,7 +2568,7 @@ func (h *Handle) LinkSetBrNeighSuppress(link Link, mode bool) error {
 	return h.setProtinfoAttr(link, mode, nl.IFLA_BRPORT_NEIGH_SUPPRESS)
 }
 
-func (h *Handle) setProtinfoAttr(link Link, mode bool, attr int) error {
+func (h *Handle) setProtinfoAttrRawVal(link Link, val []byte, attr int) error {
 	base := link.Attrs()
 	h.ensureIndex(base)
 	req := h.newNetlinkRequest(unix.RTM_SETLINK, unix.NLM_F_ACK)
@@ -2568,7 +2578,7 @@ func (h *Handle) setProtinfoAttr(link Link, mode bool, attr int) error {
 	req.AddData(msg)
 
 	br := nl.NewRtAttr(unix.IFLA_PROTINFO|unix.NLA_F_NESTED, nil)
-	br.AddRtAttr(attr, boolToByte(mode))
+	br.AddRtAttr(attr, val)
 	req.AddData(br)
 	_, err := req.Execute(unix.NETLINK_ROUTE, 0)
 	if err != nil {
@@ -2576,6 +2586,9 @@ func (h *Handle) setProtinfoAttr(link Link, mode bool, attr int) error {
 	}
 	return nil
 }
+func (h *Handle) setProtinfoAttr(link Link, mode bool, attr int) error {
+	return h.setProtinfoAttrRawVal(link, boolToByte(mode), attr)
+}
 
 // LinkSetTxQLen sets the transaction queue length for the link.
 // Equivalent to: `ip link set $link txqlen $qlen`
@@ -3541,6 +3554,9 @@ func addBridgeAttrs(bridge *Bridge, linkInfo *nl.RtAttr) {
 	if bridge.VlanDefaultPVID != nil {
 		data.AddRtAttr(nl.IFLA_BR_VLAN_DEFAULT_PVID, nl.Uint16Attr(*bridge.VlanDefaultPVID))
 	}
+	if bridge.GroupFwdMask != nil {
+		data.AddRtAttr(nl.IFLA_BR_GROUP_FWD_MASK, nl.Uint16Attr(*bridge.GroupFwdMask))
+	}
 }
 
 func parseBridgeData(bridge Link, data []syscall.NetlinkRouteAttr) {
@@ -3562,6 +3578,9 @@ func parseBridgeData(bridge Link, data []syscall.NetlinkRouteAttr) {
 		case nl.IFLA_BR_VLAN_DEFAULT_PVID:
 			vlanDefaultPVID := native.Uint16(datum.Value[0:2])
 			br.VlanDefaultPVID = &vlanDefaultPVID
+		case nl.IFLA_BR_GROUP_FWD_MASK:
+			mask := native.Uint16(datum.Value[0:2])
+			br.GroupFwdMask = &mask
 		}
 	}
 }