Cherry-pick: use ssh discover technique to check if SSH service is re…

…ally run… (#469)

use ssh discover technique to check if SSH service is really running

cmd/ignite/run/start.go

@@ -3,11 +3,12 @@ package run
 import (
  "fmt"
  "net"
+ "strings"
  "time"
 
  "github.com/weaveworks/ignite/pkg/apis/ignite"
-
  "github.com/weaveworks/ignite/pkg/operations"
+ "golang.org/x/crypto/ssh"
 )
 
 type StartFlags struct {
@@ -53,7 +54,7 @@ func Start(so *startOptions) error {
  return nil
 }
 
-func waitForSSH(vm *ignite.VM, seconds int) error {
+func dialSuccess(vm *ignite.VM, seconds int) error {
  // When --ssh is enabled, wait until SSH service started on port 22 at most N seconds
  ssh := vm.Spec.SSH
  if ssh != nil && ssh.Generate && len(vm.Status.IPAddresses) > 0 {
@@ -81,3 +82,44 @@ func waitForSSH(vm *ignite.VM, seconds int) error {
 
  return nil
 }
+
+func waitForSSH(vm *ignite.VM, seconds int) error {
+ if err := dialSuccess(vm, seconds); err != nil {
+ return err
+ }
+
+ certCheck := &ssh.CertChecker{
+ IsHostAuthority: func(auth ssh.PublicKey, address string) bool {
+ return true
+ },
+ IsRevoked: func(cert *ssh.Certificate) bool {
+ return false
+ },
+ HostKeyFallback: func(hostname string, remote net.Addr, key ssh.PublicKey) error {
+ return nil
+ },
+ }
+
+ config := &ssh.ClientConfig{
+ User: "user",
+ Auth: []ssh.AuthMethod{
+ ssh.Password("password"),
+ },
+ HostKeyCallback: certCheck.CheckHostKey,
+ Timeout: 5 * time.Second,
+ }
+
+ addr := vm.Status.IPAddresses[0].String() + ":22"
+ sshConn, err := ssh.Dial("tcp", addr, config)
+ if err != nil {
+ // If error contains "unable to authenticate", it seems able to connect the server
+ errString := err.Error()
+ if strings.Contains(errString, "unable to authenticate") {
+ return nil
+ }
+ return err
+ }
+
+ sshConn.Close()
+ return fmt.Errorf("timed out checking SSH server")
+}