1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146
|
package netlink
import (
"fmt"
"net"
"strings"
"syscall"
"github.com/vishvananda/netlink/nl"
)
// 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 {
req := nl.NewNetlinkRequest(syscall.RTM_NEWADDR, syscall.NLM_F_CREATE|syscall.NLM_F_EXCL|syscall.NLM_F_ACK)
return 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 {
req := nl.NewNetlinkRequest(syscall.RTM_DELADDR, syscall.NLM_F_ACK)
return addrHandle(link, addr, req)
}
func 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")
}
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 addrData []byte
if family == FAMILY_V4 {
addrData = addr.IP.To4()
} else {
addrData = addr.IP.To16()
}
localData := nl.NewRtAttr(syscall.IFA_LOCAL, addrData)
req.AddData(localData)
addressData := nl.NewRtAttr(syscall.IFA_ADDRESS, addrData)
req.AddData(addressData)
if addr.Flags != 0 {
b := make([]byte, 4)
native.PutUint32(b, uint32(addr.Flags))
flagsData := nl.NewRtAttr(IFA_FLAGS, b)
req.AddData(flagsData)
}
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) {
req := nl.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
}
index := 0
if link != nil {
base := link.Attrs()
ensureIndex(base)
index = base.Index
}
var res []Addr
for _, m := range msgs {
msg := nl.DeserializeIfAddrmsg(m)
if link != nil && msg.Index != uint32(index) {
// Ignore messages from other interfaces
continue
}
if family != FAMILY_ALL && msg.Family != uint8(family) {
continue
}
attrs, err := nl.ParseRouteAttr(m[msg.Len():])
if err != nil {
return nil, err
}
var local, dst *net.IPNet
var addr Addr
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)),
}
case syscall.IFA_LOCAL:
local = &net.IPNet{
IP: attr.Value,
Mask: net.CIDRMask(int(msg.Prefixlen), 8*len(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]))
}
}
// 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)
res = append(res, addr)
}
return res, nil
}
|