mirror of
https://github.com/moby/moby.git
synced 2022-11-09 12:21:53 -05:00
f5f4d2d9cb
Closes #6975 Signed-off-by: Malte Janduda <mail@janduda.net>
113 lines
2.5 KiB
Go
113 lines
2.5 KiB
Go
package networkdriver
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"net"
|
|
|
|
"github.com/docker/libcontainer/netlink"
|
|
)
|
|
|
|
var (
|
|
networkGetRoutesFct = netlink.NetworkGetRoutes
|
|
ErrNoDefaultRoute = errors.New("no default route")
|
|
)
|
|
|
|
func CheckNameserverOverlaps(nameservers []string, toCheck *net.IPNet) error {
|
|
if len(nameservers) > 0 {
|
|
for _, ns := range nameservers {
|
|
_, nsNetwork, err := net.ParseCIDR(ns)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if NetworkOverlaps(toCheck, nsNetwork) {
|
|
return ErrNetworkOverlapsWithNameservers
|
|
}
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func CheckRouteOverlaps(toCheck *net.IPNet) error {
|
|
networks, err := networkGetRoutesFct()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
for _, network := range networks {
|
|
if network.IPNet != nil && NetworkOverlaps(toCheck, network.IPNet) {
|
|
return ErrNetworkOverlaps
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Detects overlap between one IPNet and another
|
|
func NetworkOverlaps(netX *net.IPNet, netY *net.IPNet) bool {
|
|
if firstIP, _ := NetworkRange(netX); netY.Contains(firstIP) {
|
|
return true
|
|
}
|
|
if firstIP, _ := NetworkRange(netY); netX.Contains(firstIP) {
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
// Calculates the first and last IP addresses in an IPNet
|
|
func NetworkRange(network *net.IPNet) (net.IP, net.IP) {
|
|
var netIP net.IP
|
|
if network.IP.To4() != nil {
|
|
netIP = network.IP.To4()
|
|
} else if network.IP.To16() != nil {
|
|
netIP = network.IP.To16()
|
|
} else {
|
|
return nil, nil
|
|
}
|
|
|
|
lastIP := make([]byte, len(netIP), len(netIP))
|
|
|
|
for i := 0; i < len(netIP); i++ {
|
|
lastIP[i] = netIP[i] | ^network.Mask[i]
|
|
}
|
|
return netIP.Mask(network.Mask), net.IP(lastIP)
|
|
}
|
|
|
|
// Return the IPv4 address of a network interface
|
|
func GetIfaceAddr(name string) (net.Addr, error) {
|
|
iface, err := net.InterfaceByName(name)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
addrs, err := iface.Addrs()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
var addrs4 []net.Addr
|
|
for _, addr := range addrs {
|
|
ip := (addr.(*net.IPNet)).IP
|
|
if ip4 := ip.To4(); ip4 != nil {
|
|
addrs4 = append(addrs4, addr)
|
|
}
|
|
}
|
|
switch {
|
|
case len(addrs4) == 0:
|
|
return nil, fmt.Errorf("Interface %v has no IP addresses", name)
|
|
case len(addrs4) > 1:
|
|
fmt.Printf("Interface %v has more than 1 IPv4 address. Defaulting to using %v\n",
|
|
name, (addrs4[0].(*net.IPNet)).IP)
|
|
}
|
|
return addrs4[0], nil
|
|
}
|
|
|
|
func GetDefaultRouteIface() (*net.Interface, error) {
|
|
rs, err := networkGetRoutesFct()
|
|
if err != nil {
|
|
return nil, fmt.Errorf("unable to get routes: %v", err)
|
|
}
|
|
for _, r := range rs {
|
|
if r.Default {
|
|
return r.Iface, nil
|
|
}
|
|
}
|
|
return nil, ErrNoDefaultRoute
|
|
}
|