packer-cn/builder/qemu/step_forward_ssh.go

53 lines
1.2 KiB
Go

package qemu
import (
"fmt"
"log"
"math/rand"
"net"
"github.com/mitchellh/multistep"
"github.com/mitchellh/packer/packer"
)
// This step adds a NAT port forwarding definition so that SSH is available
// on the guest machine.
//
// Uses:
//
// Produces:
type stepForwardSSH struct{}
func (s *stepForwardSSH) Run(state multistep.StateBag) multistep.StepAction {
config := state.Get("config").(*config)
ui := state.Get("ui").(packer.Ui)
log.Printf("Looking for available SSH port between %d and %d", config.SSHHostPortMin, config.SSHHostPortMax)
var sshHostPort uint
var offset uint = 0
portRange := int(config.SSHHostPortMax - config.SSHHostPortMin)
if portRange > 0 {
// Have to check if > 0 to avoid a panic
offset = uint(rand.Intn(portRange))
}
for {
sshHostPort = offset + config.SSHHostPortMin
log.Printf("Trying port: %d", sshHostPort)
l, err := net.Listen("tcp", fmt.Sprintf(":%d", sshHostPort))
if err == nil {
defer l.Close()
break
}
}
ui.Say(fmt.Sprintf("Found port for SSH: %d.", sshHostPort))
// Save the port we're using so that future steps can use it
state.Put("sshHostPort", sshHostPort)
return multistep.ActionContinue
}
func (s *stepForwardSSH) Cleanup(state multistep.StateBag) {}