k3s/vendor/github.com/rakelkar/gonetsh/netroute/netroute.go

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2019-09-05 18:55:53 +00:00
package netroute
import (
"regexp"
"net"
"strconv"
"strings"
"bufio"
"bytes"
ps "github.com/bhendo/go-powershell"
psbe "github.com/bhendo/go-powershell/backend"
"fmt"
"math/big"
)
// Interface is an injectable interface for running MSFT_NetRoute commands. Implementations must be goroutine-safe.
type Interface interface {
// Get all net routes on the host
GetNetRoutesAll() ([]Route, error)
// Get net routes by link and destination subnet
GetNetRoutes(linkIndex int, destinationSubnet *net.IPNet) ([]Route, error)
// Create a new route
NewNetRoute(linkIndex int, destinationSubnet *net.IPNet, gatewayAddress net.IP) error
// Remove an existing route
RemoveNetRoute(linkIndex int, destinationSubnet *net.IPNet, gatewayAddress net.IP) error
// exit the shell
Exit()
}
type Route struct {
LinkIndex int
DestinationSubnet *net.IPNet
GatewayAddress net.IP
RouteMetric int
IfMetric int
}
type shell struct {
shellInstance ps.Shell
}
func New() Interface {
s, _ := ps.New(&psbe.Local{})
runner := &shell{
shellInstance: s,
}
return runner
}
func (shell *shell) Exit() {
shell.shellInstance.Exit()
shell.shellInstance = nil
}
func (shell *shell) GetNetRoutesAll() ([]Route, error) {
getRouteCmdLine := "get-netroute -erroraction Ignore"
stdout, err := shell.runScript(getRouteCmdLine)
if err != nil {
return nil, err
}
return parseRoutesList(stdout), nil
}
func (shell *shell) GetNetRoutes(linkIndex int, destinationSubnet *net.IPNet) ([]Route, error) {
getRouteCmdLine := fmt.Sprintf("get-netroute -InterfaceIndex %v -DestinationPrefix %v -erroraction Ignore", linkIndex, destinationSubnet.String())
stdout, err := shell.runScript(getRouteCmdLine)
if err != nil {
return nil, err
}
return parseRoutesList(stdout), nil
}
func (shell *shell) RemoveNetRoute(linkIndex int, destinationSubnet *net.IPNet, gatewayAddress net.IP) error {
removeRouteCmdLine := fmt.Sprintf("remove-netroute -InterfaceIndex %v -DestinationPrefix %v -NextHop %v -Verbose -Confirm:$false", linkIndex, destinationSubnet.String(), gatewayAddress.String())
_, err := shell.runScript(removeRouteCmdLine)
return err
}
func (shell *shell) NewNetRoute(linkIndex int, destinationSubnet *net.IPNet, gatewayAddress net.IP) error {
newRouteCmdLine := fmt.Sprintf("new-netroute -InterfaceIndex %v -DestinationPrefix %v -NextHop %v -Verbose", linkIndex, destinationSubnet.String(), gatewayAddress.String())
_, err := shell.runScript(newRouteCmdLine)
return err
}
func parseRoutesList(stdout string) []Route {
internalWhitespaceRegEx := regexp.MustCompile(`[\s\p{Zs}]{2,}`)
scanner := bufio.NewScanner(strings.NewReader(stdout))
var routes []Route
for scanner.Scan() {
line := internalWhitespaceRegEx.ReplaceAllString(scanner.Text(), "|")
if strings.HasPrefix(line, "ifIndex") || strings.HasPrefix(line, "----") {
continue
}
parts := strings.Split(line, "|")
if len(parts) != 5 {
continue
}
linkIndex, err := strconv.Atoi(parts[0])
if err != nil {
continue
}
gatewayAddress := net.ParseIP(parts[2])
if gatewayAddress == nil {
continue
}
_, destinationSubnet, err := net.ParseCIDR(parts[1])
if err != nil {
continue
}
route := Route{
DestinationSubnet: destinationSubnet,
GatewayAddress: gatewayAddress,
LinkIndex: linkIndex,
}
routes = append(routes, route)
}
return routes
}
func (r *Route) Equal(route Route) bool {
if r.DestinationSubnet.IP.Equal(route.DestinationSubnet.IP) && r.GatewayAddress.Equal(route.GatewayAddress) && bytes.Equal(r.DestinationSubnet.Mask, route.DestinationSubnet.Mask) {
return true
}
return false
}
func (shell *shell) runScript(cmdLine string) (string, error) {
stdout, _, err := shell.shellInstance.Execute(cmdLine)
if err != nil {
return "", err
}
return stdout, nil
}
func IpToInt(ip net.IP) *big.Int {
if v := ip.To4(); v != nil {
return big.NewInt(0).SetBytes(v)
}
return big.NewInt(0).SetBytes(ip.To16())
}
func IntToIP(i *big.Int) net.IP {
return net.IP(i.Bytes())
}