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@@ -1,149 +0,0 @@
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-package local
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-
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-import (
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- "fmt"
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- "net"
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- "os"
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- "strings"
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- "time"
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-
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- //"github.com/davecgh/go-spew/spew"
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- "log"
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- "os/exec"
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-
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- "github.com/gravitl/netmaker/logger"
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- "github.com/gravitl/netmaker/models"
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- "github.com/gravitl/netmaker/netclient/ncutils"
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-)
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-
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-const DNS_UNREACHABLE_ERROR = "nameserver unreachable"
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-
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-// SetDNSWithRetry - Attempt setting dns, if it fails return true (to reset dns)
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-func SetDNSWithRetry(node models.Node, address string) bool {
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- var reachable bool
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- if !hasPrereqs() {
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- return true
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- }
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- for counter := 0; !reachable && counter < 5; counter++ {
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- reachable = IsDNSReachable(address)
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- time.Sleep(time.Second << 1)
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- }
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- if !reachable {
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- logger.Log(0, "not setting dns (server unreachable), will try again later: "+address)
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- return true
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- } else if err := UpdateDNS(node.Interface, node.Network, address); err != nil {
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- logger.Log(0, "error applying dns"+err.Error())
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- } else if IsDNSWorking(node.Network, address) {
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- return true
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- }
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- resetDNS()
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- return false
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-}
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-
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-func resetDNS() {
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- ncutils.RunCmd("systemctl restart systemd-resolved", true)
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-}
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-
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-// SetDNS - sets the DNS of a local machine
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-func SetDNS(nameserver string) error {
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- bytes, err := os.ReadFile("/etc/resolv.conf")
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- if err != nil {
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- return err
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- }
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- resolvstring := string(bytes)
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- // //check whether s contains substring text
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- hasdns := strings.Contains(resolvstring, nameserver)
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- if hasdns {
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- return nil
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- }
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- resolv, err := os.OpenFile("/etc/resolv.conf", os.O_APPEND|os.O_WRONLY, 0644)
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- if err != nil {
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- return err
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- }
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- defer resolv.Close()
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- _, err = resolv.WriteString("nameserver " + nameserver + "\n")
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-
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- return err
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-}
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-
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-func hasPrereqs() bool {
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- if !ncutils.IsLinux() {
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- return false
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- }
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- _, err := exec.LookPath("resolvectl")
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- return err == nil
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-}
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-
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-// UpdateDNS - updates local DNS of client
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-func UpdateDNS(ifacename string, network string, nameserver string) error {
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- if !ncutils.IsLinux() {
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- return nil
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- }
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- if ifacename == "" {
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- return fmt.Errorf("cannot set dns: interface name is blank")
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- }
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- if network == "" {
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- return fmt.Errorf("cannot set dns: network name is blank")
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- }
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- if nameserver == "" {
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- return fmt.Errorf("cannot set dns: nameserver is blank")
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- }
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- if !IsDNSReachable(nameserver) {
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- return fmt.Errorf(DNS_UNREACHABLE_ERROR + " : " + nameserver + ":53")
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- }
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- _, err := exec.LookPath("resolvectl")
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- if err != nil {
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- log.Println(err)
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- log.Println("WARNING: resolvectl not present. Unable to set dns. Install resolvectl or run manually.")
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- } else {
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- _, err = ncutils.RunCmd("resolvectl domain "+ifacename+" ~"+network, true)
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- if err != nil {
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- log.Println("WARNING: Error encountered setting domain on dns. Aborted setting dns.")
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- } else {
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- _, err = ncutils.RunCmd("resolvectl default-route "+ifacename+" false", true)
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- if err != nil {
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- log.Println("WARNING: Error encountered setting default-route on dns. Aborted setting dns.")
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- } else {
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- _, err = ncutils.RunCmd("resolvectl dns "+ifacename+" "+nameserver, true)
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- if err != nil {
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- log.Println("WARNING: Error encountered running resolvectl dns " + ifacename + " " + nameserver)
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- }
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- }
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- }
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- }
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- return err
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-}
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-
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-// IsDNSReachable - checks if nameserver is reachable
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-func IsDNSReachable(nameserver string) bool {
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- port := "53"
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- protocols := [2]string{"tcp", "udp"}
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- for _, proto := range protocols {
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- timeout := time.Second
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- conn, err := net.DialTimeout(proto, net.JoinHostPort(nameserver, port), timeout)
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- if err != nil {
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- return false
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- }
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- if conn != nil {
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- defer conn.Close()
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- } else {
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- return false
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- }
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- }
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- return true
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-}
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-
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-// IsDNSWorking - checks if record is returned by correct nameserver
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-func IsDNSWorking(network string, nameserver string) bool {
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- var isworking bool
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- servers, err := net.LookupNS("netmaker" + "." + network)
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- if err != nil {
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- return isworking
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- }
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- for _, ns := range servers {
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- if strings.Contains(ns.Host, nameserver) {
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- isworking = true
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- }
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- }
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- return isworking
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-}
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