netlink/chain_linux.go
Ivan Kolodyazhny 378a404a26 Implement chains support
This patch implements both tc and filter chains.

We also need to align tc filter delition implementation
with iprote2 to delete filters withichain by passing
additional bits during filter deletion call.
2022-12-14 10:59:49 -08:00

113 lines
2.6 KiB
Go

package netlink
import (
"github.com/vishvananda/netlink/nl"
"golang.org/x/sys/unix"
)
// ChainDel will delete a chain from the system.
func ChainDel(link Link, chain Chain) error {
// Equivalent to: `tc chain del $chain`
return pkgHandle.ChainDel(link, chain)
}
// ChainDel will delete a chain from the system.
// Equivalent to: `tc chain del $chain`
func (h *Handle) ChainDel(link Link, chain Chain) error {
return h.chainModify(unix.RTM_DELCHAIN, 0, link, chain)
}
// ChainAdd will add a chain to the system.
// Equivalent to: `tc chain add`
func ChainAdd(link Link, chain Chain) error {
return pkgHandle.ChainAdd(link, chain)
}
// ChainAdd will add a chain to the system.
// Equivalent to: `tc chain add`
func (h *Handle) ChainAdd(link Link, chain Chain) error {
return h.chainModify(
unix.RTM_NEWCHAIN,
unix.NLM_F_CREATE|unix.NLM_F_EXCL,
link,
chain)
}
func (h *Handle) chainModify(cmd, flags int, link Link, chain Chain) error {
req := h.newNetlinkRequest(cmd, flags|unix.NLM_F_ACK)
index := int32(0)
if link != nil {
base := link.Attrs()
h.ensureIndex(base)
index = int32(base.Index)
}
msg := &nl.TcMsg{
Family: nl.FAMILY_ALL,
Ifindex: index,
Parent: chain.Parent,
}
req.AddData(msg)
req.AddData(nl.NewRtAttr(nl.TCA_CHAIN, nl.Uint32Attr(chain.Chain)))
_, err := req.Execute(unix.NETLINK_ROUTE, 0)
return err
}
// ChainList gets a list of chains in the system.
// Equivalent to: `tc chain list`.
// The list can be filtered by link.
func ChainList(link Link, parent uint32) ([]Chain, error) {
return pkgHandle.ChainList(link, parent)
}
// ChainList gets a list of chains in the system.
// Equivalent to: `tc chain list`.
// The list can be filtered by link.
func (h *Handle) ChainList(link Link, parent uint32) ([]Chain, error) {
req := h.newNetlinkRequest(unix.RTM_GETCHAIN, unix.NLM_F_DUMP)
index := int32(0)
if link != nil {
base := link.Attrs()
h.ensureIndex(base)
index = int32(base.Index)
}
msg := &nl.TcMsg{
Family: nl.FAMILY_ALL,
Ifindex: index,
Parent: parent,
}
req.AddData(msg)
msgs, err := req.Execute(unix.NETLINK_ROUTE, unix.RTM_NEWCHAIN)
if err != nil {
return nil, err
}
var res []Chain
for _, m := range msgs {
msg := nl.DeserializeTcMsg(m)
attrs, err := nl.ParseRouteAttr(m[msg.Len():])
if err != nil {
return nil, err
}
// skip chains from other interfaces
if link != nil && msg.Ifindex != index {
continue
}
var chain Chain
for _, attr := range attrs {
switch attr.Attr.Type {
case nl.TCA_CHAIN:
chain.Chain = native.Uint32(attr.Value)
chain.Parent = parent
}
}
res = append(res, chain)
}
return res, nil
}