Adding the ability to skip nat port forwarding for ssh connectivity

builder/virtualbox/common/ssh_config.go

@@ -16,6 +16,7 @@ type SSHConfig struct {
 	SSHPort           uint   `mapstructure:"ssh_port"`
 	SSHUser           string `mapstructure:"ssh_username"`
 	RawSSHWaitTimeout string `mapstructure:"ssh_wait_timeout"`
+	SSHSkipNatMapping bool   `mapstructure:"ssh_skip_nat_mapping"`
 
 	SSHWaitTimeout time.Duration
 }

builder/virtualbox/common/step_export.go

@@ -17,9 +17,10 @@ import (
 // Produces:
 //   exportPath string - The path to the resulting export.
 type StepExport struct {
-	Format     string
-	OutputDir  string
-	ExportOpts []string
+	Format         string
+	OutputDir      string
+	ExportOpts     []string
+	SkipNatMapping bool
 }
 
 func (s *StepExport) Run(state multistep.StateBag) multistep.StepAction {
@@ -33,15 +34,19 @@ func (s *StepExport) Run(state multistep.StateBag) multistep.StepAction {
 
 	// Clear out the Packer-created forwarding rule
 	ui.Say("Preparing to export machine...")
-	ui.Message(fmt.Sprintf(
-		"Deleting forwarded port mapping for SSH (host port %d)",
-		state.Get("sshHostPort")))
-	command := []string{"modifyvm", vmName, "--natpf1", "delete", "packerssh"}
-	if err := driver.VBoxManage(command...); err != nil {
-		err := fmt.Errorf("Error deleting port forwarding rule: %s", err)
-		state.Put("error", err)
-		ui.Error(err.Error())
-		return multistep.ActionHalt
+	var command []string
+
+	if s.SkipNatMapping == false {
+		ui.Message(fmt.Sprintf(
+			"Deleting forwarded port mapping for SSH (host port %d)",
+			state.Get("sshHostPort")))
+		command := []string{"modifyvm", vmName, "--natpf1", "delete", "packerssh"}
+		if err := driver.VBoxManage(command...); err != nil {
+			err := fmt.Errorf("Error deleting port forwarding rule: %s", err)
+			state.Put("error", err)
+			ui.Error(err.Error())
+			return multistep.ActionHalt
+		}
 	}
 
 	// Export the VM to an OVF

builder/virtualbox/common/step_forward_ssh.go

@@ -19,9 +19,10 @@ import (
 //
 // Produces:
 type StepForwardSSH struct {
-	GuestPort   uint
-	HostPortMin uint
-	HostPortMax uint
+	GuestPort      uint
+	HostPortMin    uint
+	HostPortMax    uint
+	SkipNatMapping bool
 }
 
 func (s *StepForwardSSH) Run(state multistep.StateBag) multistep.StepAction {
@@ -29,39 +30,44 @@ func (s *StepForwardSSH) Run(state multistep.StateBag) multistep.StepAction {
 	ui := state.Get("ui").(packer.Ui)
 	vmName := state.Get("vmName").(string)
 
-	log.Printf("Looking for available SSH port between %d and %d",
-		s.HostPortMin, s.HostPortMax)
 	var sshHostPort uint
-	var offset uint = 0
+	if s.SkipNatMapping {
+		sshHostPort = s.GuestPort
+		log.Printf("Skipping SSH NAT mapping and using SSH port %d", sshHostPort)
+	} else {
+		log.Printf("Looking for available SSH port between %d and %d",
+			s.HostPortMin, s.HostPortMax)
+		var offset uint = 0
 
-	portRange := int(s.HostPortMax - s.HostPortMin)
-	if portRange > 0 {
-		// Have to check if > 0 to avoid a panic
-		offset = uint(rand.Intn(portRange))
-	}
+		portRange := int(s.HostPortMax - s.HostPortMin)
+		if portRange > 0 {
+			// Have to check if > 0 to avoid a panic
+			offset = uint(rand.Intn(portRange))
+		}
 
-	for {
-		sshHostPort = offset + s.HostPortMin
-		log.Printf("Trying port: %d", sshHostPort)
-		l, err := net.Listen("tcp", fmt.Sprintf("127.0.0.1:%d", sshHostPort))
-		if err == nil {
-			defer l.Close()
-			break
+		for {
+			sshHostPort = offset + s.HostPortMin
+			log.Printf("Trying port: %d", sshHostPort)
+			l, err := net.Listen("tcp", fmt.Sprintf("127.0.0.1:%d", sshHostPort))
+			if err == nil {
+				defer l.Close()
+				break
+			}
 		}
-	}
 
-	// Create a forwarded port mapping to the VM
-	ui.Say(fmt.Sprintf("Creating forwarded port mapping for SSH (host port %d)", sshHostPort))
-	command := []string{
-		"modifyvm", vmName,
-		"--natpf1",
-		fmt.Sprintf("packerssh,tcp,127.0.0.1,%d,,%d", sshHostPort, s.GuestPort),
-	}
-	if err := driver.VBoxManage(command...); err != nil {
-		err := fmt.Errorf("Error creating port forwarding rule: %s", err)
-		state.Put("error", err)
-		ui.Error(err.Error())
-		return multistep.ActionHalt
+		// Create a forwarded port mapping to the VM
+		ui.Say(fmt.Sprintf("Creating forwarded port mapping for SSH (host port %d)", sshHostPort))
+		command := []string{
+			"modifyvm", vmName,
+			"--natpf1",
+			fmt.Sprintf("packerssh,tcp,127.0.0.1,%d,,%d", sshHostPort, s.GuestPort),
+		}
+		if err := driver.VBoxManage(command...); err != nil {
+			err := fmt.Errorf("Error creating port forwarding rule: %s", err)
+			state.Put("error", err)
+			ui.Error(err.Error())
+			return multistep.ActionHalt
+		}
 	}
 
 	// Save the port we're using so that future steps can use it

builder/virtualbox/iso/builder.go

@@ -290,9 +290,10 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 		new(stepAttachGuestAdditions),
 		new(vboxcommon.StepAttachFloppy),
 		&vboxcommon.StepForwardSSH{
-			GuestPort:   b.config.SSHPort,
-			HostPortMin: b.config.SSHHostPortMin,
-			HostPortMax: b.config.SSHHostPortMax,
+			GuestPort:      b.config.SSHPort,
+			HostPortMin:    b.config.SSHHostPortMin,
+			HostPortMax:    b.config.SSHHostPortMax,
+			SkipNatMapping: b.config.SSHSkipNatMapping,
 		},
 		&vboxcommon.StepVBoxManage{
 			Commands: b.config.VBoxManage,
@@ -319,9 +320,10 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 		},
 		new(vboxcommon.StepRemoveDevices),
 		&vboxcommon.StepExport{
-			Format:     b.config.Format,
-			OutputDir:  b.config.OutputDir,
-			ExportOpts: b.config.ExportOpts.ExportOpts,
+			Format:         b.config.Format,
+			OutputDir:      b.config.OutputDir,
+			ExportOpts:     b.config.ExportOpts.ExportOpts,
+			SkipNatMapping: b.config.SSHSkipNatMapping,
 		},
 	}
 

builder/virtualbox/ovf/builder.go

@@ -65,9 +65,10 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 		*/
 		new(vboxcommon.StepAttachFloppy),
 		&vboxcommon.StepForwardSSH{
-			GuestPort:   b.config.SSHPort,
-			HostPortMin: b.config.SSHHostPortMin,
-			HostPortMax: b.config.SSHHostPortMax,
+			GuestPort:      b.config.SSHPort,
+			HostPortMin:    b.config.SSHHostPortMin,
+			HostPortMax:    b.config.SSHHostPortMax,
+			SkipNatMapping: b.config.SSHSkipNatMapping,
 		},
 		&vboxcommon.StepVBoxManage{
 			Commands: b.config.VBoxManage,
@@ -95,9 +96,10 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 		},
 		new(vboxcommon.StepRemoveDevices),
 		&vboxcommon.StepExport{
-			Format:     b.config.Format,
-			OutputDir:  b.config.OutputDir,
-			ExportOpts: b.config.ExportOpts.ExportOpts,
+			Format:         b.config.Format,
+			OutputDir:      b.config.OutputDir,
+			ExportOpts:     b.config.ExportOpts.ExportOpts,
+			SkipNatMapping: b.config.SSHSkipNatMapping,
 		},
 	}
 

website/source/docs/builders/virtualbox-iso.html.markdown

@@ -191,6 +191,10 @@ Optional:
   available. By default this is "20m", or 20 minutes. Note that this should
   be quite long since the timer begins as soon as the virtual machine is booted.
 
+* `ssh_skip_nat_mapping` (bool) - Defaults to false. When enabled, Packer does
+  not setup forwarded port mapping for SSH requests and uses `ssh_port` on the
+  host to communicate to the virtual machine
+
 * `vboxmanage` (array of array of strings) - Custom `VBoxManage` commands to
   execute in order to further customize the virtual machine being created.
   The value of this is an array of commands to execute. The commands are executed

website/source/docs/builders/virtualbox-ovf.html.markdown

@@ -126,6 +126,10 @@ Optional:
   available. By default this is "20m", or 20 minutes. Note that this should
   be quite long since the timer begins as soon as the virtual machine is booted.
 
+* `ssh_skip_nat_mapping` (bool) - Defaults to false. When enabled, Packer does
+  not setup forwarded port mapping for SSH requests and uses `ssh_port` on the
+  host to communicate to the virtual machine
+
 * `vboxmanage` (array of array of strings) - Custom `VBoxManage` commands to
   execute in order to further customize the virtual machine being created.
   The value of this is an array of commands to execute. The commands are executed