Merge pull request #4101 from lwander/f-googlecompute-ssh-private-key-file

builder/googlecompute: Use ssh_private_key_file if provided

builder/googlecompute/builder.go

@@ -52,8 +52,9 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 	steps := []multistep.Step{
 		new(StepCheckExistingImage),
 		&StepCreateSSHKey{
-			Debug:        b.config.PackerDebug,
-			DebugKeyPath: fmt.Sprintf("gce_%s.pem", b.config.PackerBuildName),
+			Debug:          b.config.PackerDebug,
+			DebugKeyPath:   fmt.Sprintf("gce_%s.pem", b.config.PackerBuildName),
+			PrivateKeyFile: b.config.Comm.SSHPrivateKey,
 		},
 		&StepCreateInstance{
 			Debug: b.config.PackerDebug,

builder/googlecompute/step_create_instance.go

@@ -24,13 +24,17 @@ func (c *Config) createInstanceMetadata(sourceImage *Image, sshPublicKey string)
 		instanceMetadata[k] = v
 	}
 
-	// Merge any existing ssh keys with our public key.
-	sshMetaKey := "sshKeys"
-	sshKeys := fmt.Sprintf("%s:%s", c.Comm.SSHUsername, sshPublicKey)
-	if confSshKeys, exists := instanceMetadata[sshMetaKey]; exists {
-		sshKeys = fmt.Sprintf("%s\n%s", sshKeys, confSshKeys)
+	// Merge any existing ssh keys with our public key, unless there is no
+	// supplied public key. This is possible if a private_key_file was
+	// specified.
+	if sshPublicKey != "" {
+		sshMetaKey := "sshKeys"
+		sshKeys := fmt.Sprintf("%s:%s", c.Comm.SSHUsername, sshPublicKey)
+		if confSshKeys, exists := instanceMetadata[sshMetaKey]; exists {
+			sshKeys = fmt.Sprintf("%s\n%s", sshKeys, confSshKeys)
+		}
+		instanceMetadata[sshMetaKey] = sshKeys
 	}
-	instanceMetadata[sshMetaKey] = sshKeys
 
 	// Wrap any startup script with our own startup script.
 	if c.StartupScriptFile != "" {

builder/googlecompute/step_create_instance_test.go

@@ -2,6 +2,7 @@ package googlecompute
 
 import (
 	"errors"
+	"strings"
 	"testing"
 	"time"
 
@@ -210,3 +211,33 @@ func TestStepCreateInstance_errorTimeout(t *testing.T) {
 	_, ok = state.GetOk("instance_name")
 	assert.False(t, ok, "State should not have an instance name.")
 }
+
+func TestCreateInstanceMetadata(t *testing.T) {
+	state := testState(t)
+	c := state.Get("config").(*Config)
+	image := StubImage("test-image", "test-project", []string{}, 100)
+	key := "abcdefgh12345678"
+
+	// create our metadata
+	metadata, err := c.createInstanceMetadata(image, key)
+
+	assert.True(t, err == nil, "Metadata creation should have succeeded.")
+
+	// ensure our key is listed
+	assert.True(t, strings.Contains(metadata["sshKeys"], key), "Instance metadata should contain provided key")
+}
+
+func TestCreateInstanceMetadata_noPublicKey(t *testing.T) {
+	state := testState(t)
+	c := state.Get("config").(*Config)
+	image := StubImage("test-image", "test-project", []string{}, 100)
+	sshKeys := c.Metadata["sshKeys"]
+
+	// create our metadata
+	metadata, err := c.createInstanceMetadata(image, "")
+
+	assert.True(t, err == nil, "Metadata creation should have succeeded.")
+
+	// ensure the ssh metadata hasn't changed
+	assert.Equal(t, metadata["sshKeys"], sshKeys, "Instance metadata should not have been modified")
+}

builder/googlecompute/step_create_ssh_key.go

@@ -6,6 +6,7 @@ import (
 	"crypto/x509"
 	"encoding/pem"
 	"fmt"
+	"io/ioutil"
 	"os"
 
 	"github.com/mitchellh/multistep"
@@ -15,8 +16,9 @@ import (
 
 // StepCreateSSHKey represents a Packer build step that generates SSH key pairs.
 type StepCreateSSHKey struct {
-	Debug        bool
-	DebugKeyPath string
+	Debug          bool
+	DebugKeyPath   string
+	PrivateKeyFile string
 }
 
 // Run executes the Packer build step that generates SSH key pairs.
@@ -25,6 +27,21 @@ type StepCreateSSHKey struct {
 func (s *StepCreateSSHKey) Run(state multistep.StateBag) multistep.StepAction {
 	ui := state.Get("ui").(packer.Ui)
 
+	if s.PrivateKeyFile != "" {
+		ui.Say("Using existing SSH private key")
+		privateKeyBytes, err := ioutil.ReadFile(s.PrivateKeyFile)
+		if err != nil {
+			state.Put("error", fmt.Errorf(
+				"Error loading configured private key file: %s", err))
+			return multistep.ActionHalt
+		}
+
+		state.Put("ssh_private_key", string(privateKeyBytes))
+		state.Put("ssh_public_key", "")
+
+		return multistep.ActionContinue
+	}
+
 	ui.Say("Creating temporary SSH key for instance...")
 	priv, err := rsa.GenerateKey(rand.Reader, 2048)
 	if err != nil {

builder/googlecompute/step_create_ssh_key_test.go

@@ -12,6 +12,23 @@ func TestStepCreateSSHKey_impl(t *testing.T) {
 	var _ multistep.Step = new(StepCreateSSHKey)
 }
 
+func TestStepCreateSSHKey_privateKey(t *testing.T) {
+	state := testState(t)
+	step := new(StepCreateSSHKey)
+	step.PrivateKeyFile = "test-fixtures/fake-key"
+	defer step.Cleanup(state)
+
+	// run the step
+	if action := step.Run(state); action != multistep.ActionContinue {
+		t.Fatalf("bad action: %#v", action)
+	}
+
+	// Verify that we have a public/private key
+	if _, ok := state.GetOk("ssh_private_key"); !ok {
+		t.Fatal("should have key")
+	}
+}
+
 func TestStepCreateSSHKey(t *testing.T) {
 	state := testState(t)
 	step := new(StepCreateSSHKey)

builder/googlecompute/test-fixtures/fake-key

@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=
+-----END RSA PRIVATE KEY-----