cri-o/vendor/github.com/vishvananda/netlink/addr_linux.go

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package netlink
import (
"fmt"
"log"
"net"
"strings"
"syscall"
"github.com/vishvananda/netlink/nl"
"github.com/vishvananda/netns"
)
// IFA_FLAGS is a u32 attribute.
const IFA_FLAGS = 0x8
// AddrAdd will add an IP address to a link device.
// Equivalent to: `ip addr add $addr dev $link`
func AddrAdd(link Link, addr *Addr) error {
return pkgHandle.AddrAdd(link, addr)
}
// AddrAdd will add an IP address to a link device.
// Equivalent to: `ip addr add $addr dev $link`
func (h *Handle) AddrAdd(link Link, addr *Addr) error {
req := h.newNetlinkRequest(syscall.RTM_NEWADDR, syscall.NLM_F_CREATE|syscall.NLM_F_EXCL|syscall.NLM_F_ACK)
return h.addrHandle(link, addr, req)
}
// AddrReplace will replace (or, if not present, add) an IP address on a link device.
// Equivalent to: `ip addr replace $addr dev $link`
func AddrReplace(link Link, addr *Addr) error {
return pkgHandle.AddrReplace(link, addr)
}
// AddrReplace will replace (or, if not present, add) an IP address on a link device.
// Equivalent to: `ip addr replace $addr dev $link`
func (h *Handle) AddrReplace(link Link, addr *Addr) error {
req := h.newNetlinkRequest(syscall.RTM_NEWADDR, syscall.NLM_F_CREATE|syscall.NLM_F_REPLACE|syscall.NLM_F_ACK)
return h.addrHandle(link, addr, req)
}
// AddrDel will delete an IP address from a link device.
// Equivalent to: `ip addr del $addr dev $link`
func AddrDel(link Link, addr *Addr) error {
return pkgHandle.AddrDel(link, addr)
}
// AddrDel will delete an IP address from a link device.
// Equivalent to: `ip addr del $addr dev $link`
func (h *Handle) AddrDel(link Link, addr *Addr) error {
req := h.newNetlinkRequest(syscall.RTM_DELADDR, syscall.NLM_F_ACK)
return h.addrHandle(link, addr, req)
}
func (h *Handle) addrHandle(link Link, addr *Addr, req *nl.NetlinkRequest) error {
base := link.Attrs()
if addr.Label != "" && !strings.HasPrefix(addr.Label, base.Name) {
return fmt.Errorf("label must begin with interface name")
}
h.ensureIndex(base)
family := nl.GetIPFamily(addr.IP)
msg := nl.NewIfAddrmsg(family)
msg.Index = uint32(base.Index)
msg.Scope = uint8(addr.Scope)
prefixlen, _ := addr.Mask.Size()
msg.Prefixlen = uint8(prefixlen)
req.AddData(msg)
var localAddrData []byte
if family == FAMILY_V4 {
localAddrData = addr.IP.To4()
} else {
localAddrData = addr.IP.To16()
}
localData := nl.NewRtAttr(syscall.IFA_LOCAL, localAddrData)
req.AddData(localData)
var peerAddrData []byte
if addr.Peer != nil {
if family == FAMILY_V4 {
peerAddrData = addr.Peer.IP.To4()
} else {
peerAddrData = addr.Peer.IP.To16()
}
} else {
peerAddrData = localAddrData
}
addressData := nl.NewRtAttr(syscall.IFA_ADDRESS, peerAddrData)
req.AddData(addressData)
if addr.Flags != 0 {
if addr.Flags <= 0xff {
msg.IfAddrmsg.Flags = uint8(addr.Flags)
} else {
b := make([]byte, 4)
native.PutUint32(b, uint32(addr.Flags))
flagsData := nl.NewRtAttr(IFA_FLAGS, b)
req.AddData(flagsData)
}
}
if addr.Broadcast != nil {
req.AddData(nl.NewRtAttr(syscall.IFA_BROADCAST, addr.Broadcast))
}
if addr.Label != "" {
labelData := nl.NewRtAttr(syscall.IFA_LABEL, nl.ZeroTerminated(addr.Label))
req.AddData(labelData)
}
_, err := req.Execute(syscall.NETLINK_ROUTE, 0)
return err
}
// AddrList gets a list of IP addresses in the system.
// Equivalent to: `ip addr show`.
// The list can be filtered by link and ip family.
func AddrList(link Link, family int) ([]Addr, error) {
return pkgHandle.AddrList(link, family)
}
// AddrList gets a list of IP addresses in the system.
// Equivalent to: `ip addr show`.
// The list can be filtered by link and ip family.
func (h *Handle) AddrList(link Link, family int) ([]Addr, error) {
req := h.newNetlinkRequest(syscall.RTM_GETADDR, syscall.NLM_F_DUMP)
msg := nl.NewIfInfomsg(family)
req.AddData(msg)
msgs, err := req.Execute(syscall.NETLINK_ROUTE, syscall.RTM_NEWADDR)
if err != nil {
return nil, err
}
indexFilter := 0
if link != nil {
base := link.Attrs()
h.ensureIndex(base)
indexFilter = base.Index
}
var res []Addr
for _, m := range msgs {
addr, msgFamily, ifindex, err := parseAddr(m)
if err != nil {
return res, err
}
if link != nil && ifindex != indexFilter {
// Ignore messages from other interfaces
continue
}
if family != FAMILY_ALL && msgFamily != family {
continue
}
res = append(res, addr)
}
return res, nil
}
func parseAddr(m []byte) (addr Addr, family, index int, err error) {
msg := nl.DeserializeIfAddrmsg(m)
family = -1
index = -1
attrs, err1 := nl.ParseRouteAttr(m[msg.Len():])
if err1 != nil {
err = err1
return
}
family = int(msg.Family)
index = int(msg.Index)
var local, dst *net.IPNet
for _, attr := range attrs {
switch attr.Attr.Type {
case syscall.IFA_ADDRESS:
dst = &net.IPNet{
IP: attr.Value,
Mask: net.CIDRMask(int(msg.Prefixlen), 8*len(attr.Value)),
}
addr.Peer = dst
case syscall.IFA_LOCAL:
local = &net.IPNet{
IP: attr.Value,
Mask: net.CIDRMask(int(msg.Prefixlen), 8*len(attr.Value)),
}
addr.IPNet = local
case syscall.IFA_BROADCAST:
addr.Broadcast = attr.Value
case syscall.IFA_LABEL:
addr.Label = string(attr.Value[:len(attr.Value)-1])
case IFA_FLAGS:
addr.Flags = int(native.Uint32(attr.Value[0:4]))
case nl.IFA_CACHEINFO:
ci := nl.DeserializeIfaCacheInfo(attr.Value)
addr.PreferedLft = int(ci.IfaPrefered)
addr.ValidLft = int(ci.IfaValid)
}
}
// IFA_LOCAL should be there but if not, fall back to IFA_ADDRESS
if local != nil {
addr.IPNet = local
} else {
addr.IPNet = dst
}
addr.Scope = int(msg.Scope)
return
}
type AddrUpdate struct {
LinkAddress net.IPNet
LinkIndex int
Flags int
Scope int
PreferedLft int
ValidLft int
NewAddr bool // true=added false=deleted
}
// AddrSubscribe takes a chan down which notifications will be sent
// when addresses change. Close the 'done' chan to stop subscription.
func AddrSubscribe(ch chan<- AddrUpdate, done <-chan struct{}) error {
return addrSubscribe(netns.None(), netns.None(), ch, done)
}
// AddrSubscribeAt works like AddrSubscribe plus it allows the caller
// to choose the network namespace in which to subscribe (ns).
func AddrSubscribeAt(ns netns.NsHandle, ch chan<- AddrUpdate, done <-chan struct{}) error {
return addrSubscribe(ns, netns.None(), ch, done)
}
func addrSubscribe(newNs, curNs netns.NsHandle, ch chan<- AddrUpdate, done <-chan struct{}) error {
s, err := nl.SubscribeAt(newNs, curNs, syscall.NETLINK_ROUTE, syscall.RTNLGRP_IPV4_IFADDR, syscall.RTNLGRP_IPV6_IFADDR)
if err != nil {
return err
}
if done != nil {
go func() {
<-done
s.Close()
}()
}
go func() {
defer close(ch)
for {
msgs, err := s.Receive()
if err != nil {
log.Printf("netlink.AddrSubscribe: Receive() error: %v", err)
return
}
for _, m := range msgs {
msgType := m.Header.Type
if msgType != syscall.RTM_NEWADDR && msgType != syscall.RTM_DELADDR {
log.Printf("netlink.AddrSubscribe: bad message type: %d", msgType)
continue
}
addr, _, ifindex, err := parseAddr(m.Data)
if err != nil {
log.Printf("netlink.AddrSubscribe: could not parse address: %v", err)
continue
}
ch <- AddrUpdate{LinkAddress: *addr.IPNet,
LinkIndex: ifindex,
NewAddr: msgType == syscall.RTM_NEWADDR,
Flags: addr.Flags,
Scope: addr.Scope,
PreferedLft: addr.PreferedLft,
ValidLft: addr.ValidLft}
}
}
}()
return nil
}