Merge pull request #193 from hashicorp/custom_vnc_password

custom VNC password changes

Author: anshulsharma-hashicorp

.web-docs/components/builder/qemu/README.md

@@ -435,6 +435,8 @@ necessary for this build to succeed and can be found further down the page.
   automatically enables the QMP socket. See `qmp_socket_path`. Defaults to
   `false`.
 
+- `vnc_password` (string) - The password to set when VNCUsePassword == true.
+
 - `vnc_port_min` (int) - The minimum and maximum port
   to use for VNC access to the virtual machine. The builder uses VNC to type
   the initial boot_command. Because Packer generally runs in parallel,

builder/qemu/config.go

@@ -566,6 +566,8 @@ type Config struct {
 	// automatically enables the QMP socket. See `qmp_socket_path`. Defaults to
 	// `false`.
 	VNCUsePassword bool `mapstructure:"vnc_use_password" required:"false"`
+	// The password to set when VNCUsePassword == true.
+	VNCPassword string `mapstructure:"vnc_password" required:"false"`
 	// The minimum and maximum port
 	// to use for VNC access to the virtual machine. The builder uses VNC to type
 	// the initial boot_command. Because Packer generally runs in parallel,

builder/qemu/config.hcl2spec.go

@@ -15,6 +15,7 @@ import (
 	"github.com/hashicorp/packer-plugin-sdk/common"
 	packersdk "github.com/hashicorp/packer-plugin-sdk/packer"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 var testPem = `
@@ -714,3 +715,51 @@ func TestBuilderPrepare_cd_content(t *testing.T) {
 		t.Fatal("cd_content empty")
 	}
 }
+
+func TestVNCPasswordEmptyWhenUsePasswordFalse(t *testing.T) {
+	var c Config
+	config := testConfig()
+	config["vnc_use_password"] = false
+	config["vnc_password"] = "supersecret"
+	warns, err := c.Prepare(config)
+	require.NoError(t, err)
+	assert.Len(t, warns, 0, "bad: %#v", warns)
+	pass, _ := VNCPassword(&c)
+	assert.Empty(t, pass)
+}
+
+func TestVNCPasswordRandomWhenVNCPasswordEmpty(t *testing.T) {
+	var c Config
+	config := testConfig()
+	config["vnc_use_password"] = true
+	config["vnc_password"] = ""
+	warns, err := c.Prepare(config)
+	require.NoError(t, err)
+	assert.Len(t, warns, 0, "bad: %#v", warns)
+	pass, _ := VNCPassword(&c)
+	assert.Len(t, pass, 8)
+}
+
+func TestVNCPasswordSetWhenVNCPasswordNotEmpty(t *testing.T) {
+	var c Config
+	config := testConfig()
+	config["vnc_use_password"] = true
+	config["vnc_password"] = "secret"
+	warns, err := c.Prepare(config)
+	require.NoError(t, err)
+	assert.Len(t, warns, 0, "bad: %#v", warns)
+	pass, _ := VNCPassword(&c)
+	assert.Equal(t, pass, config["vnc_password"])
+}
+
+func TestVNCPasswordErrorWhenPasswordLenMoreThan8(t *testing.T) {
+	var c Config
+	config := testConfig()
+	config["vnc_use_password"] = true
+	config["vnc_password"] = "secretpassword"
+	warns, err := c.Prepare(config)
+	require.NoError(t, err)
+	assert.Len(t, warns, 0, "bad: %#v", warns)
+	_, err = VNCPassword(&c)
+	assert.Error(t, err)
+}

builder/qemu/config_test.go

@@ -28,7 +28,19 @@ type stepConfigureVNC struct {
 	l *net.Listener
 }
 
-func VNCPassword() string {
+func VNCPassword(c *Config) (string, error) {
+	if !c.VNCUsePassword {
+		return "", nil
+	}
+
+	if len(c.VNCPassword) > 8 {
+		return "", fmt.Errorf("password length is longer than expected %d > %d", len(c.VNCPassword), 8)
+	}
+
+	if len(c.VNCPassword) != 0 {
+		return c.VNCPassword, nil
+	}
+
 	length := int(8)
 
 	charSet := []byte("012345689abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
@@ -40,7 +52,7 @@ func VNCPassword() string {
 		password[i] = charSet[rand.Intn(charSetLength)]
 	}
 
-	return string(password)
+	return string(password), nil
 }
 
 func (s *stepConfigureVNC) Run(ctx context.Context, state multistep.StateBag) multistep.StepAction {
@@ -71,10 +83,12 @@ func (s *stepConfigureVNC) Run(ctx context.Context, state multistep.StateBag) mu
 	s.l.Listener.Close() // free port, but don't unlock lock file
 	vncPort := s.l.Port
 
-	if config.VNCUsePassword {
-		vncPassword = VNCPassword()
-	} else {
-		vncPassword = ""
+	vncPassword, err = VNCPassword(config)
+	if err != nil {
+		err := fmt.Errorf("Error finding VNC password: %s", err)
+		state.Put("error", err)
+		ui.Error(err.Error())
+		return multistep.ActionHalt
 	}
 
 	log.Printf("Found available VNC port: %d on IP: %s", vncPort, config.VNCBindAddress)

builder/qemu/step_configure_vnc.go

@@ -335,6 +335,8 @@
   automatically enables the QMP socket. See `qmp_socket_path`. Defaults to
   `false`.
 
+- `vnc_password` (string) - The password to set when VNCUsePassword == true.
+
 - `vnc_port_min` (int) - The minimum and maximum port
   to use for VNC access to the virtual machine. The builder uses VNC to type
   the initial boot_command. Because Packer generally runs in parallel,