diff --git a/cloudinit/cloud_config_test.go b/cloudinit/cloud_config_test.go
index 81158f2..76e5b82 100644
--- a/cloudinit/cloud_config_test.go
+++ b/cloudinit/cloud_config_test.go
@@ -91,8 +91,8 @@ hostname: trontastic
 		if wf.Encoding != "" {
 			t.Errorf("WriteFile has incorrect encoding %s", wf.Encoding)
 		}
-		if wf.Permissions != "0644" {
-			t.Errorf("WriteFile has incorrect permissions %s", wf.Permissions)
+		if perm, _ := wf.Permissions(); perm != 0644 {
+			t.Errorf("WriteFile has incorrect permissions %s", perm)
 		}
 		if wf.Path != "/etc/dogepack.conf" {
 			t.Errorf("WriteFile has incorrect path %s", wf.Path)
diff --git a/cloudinit/write_file.go b/cloudinit/write_file.go
index 601b725..8f43bbc 100644
--- a/cloudinit/write_file.go
+++ b/cloudinit/write_file.go
@@ -2,6 +2,7 @@ package cloudinit
 
 import (
 	"errors"
+	"fmt"
 	"io/ioutil"
 	"os"
 	"os/exec"
@@ -10,27 +11,43 @@ import (
 )
 
 type WriteFile struct {
-	Encoding    string
-	Content     string
-	Owner       string
-	Path        string
-	Permissions string
+	Encoding           string
+	Content            string
+	Owner              string
+	Path               string
+	RawFilePermissions string `yaml:"permissions"`
+}
+
+func (wf *WriteFile) Permissions() (os.FileMode, error) {
+	if wf.RawFilePermissions == "" {
+		return os.FileMode(0644), nil
+	}
+
+	// Parse string representation of file mode as octal
+	perm, err := strconv.ParseInt(wf.RawFilePermissions, 8, 32)
+	if err != nil {
+		return 0, errors.New("Unable to parse file permissions as octal integer")
+	}
+	return os.FileMode(perm), nil
 }
 
 func ProcessWriteFile(base string, wf *WriteFile) error {
+	if wf.Encoding != "" {
+		return fmt.Errorf("Unable to write file with encoding %s", wf.Encoding)
+	}
+
 	fullPath := path.Join(base, wf.Path)
 
 	if err := os.MkdirAll(path.Dir(fullPath), os.FileMode(0744)); err != nil {
 		return err
 	}
 
-	// Parse string representation of file mode as octal
-	perm, err := strconv.ParseInt(wf.Permissions, 8, 32)
+	perm, err := wf.Permissions()
 	if err != nil {
-		return errors.New("Unable to parse file permissions as octal integer")
+		return err
 	}
 
-	if err := ioutil.WriteFile(fullPath, []byte(wf.Content), os.FileMode(perm)); err != nil {
+	if err := ioutil.WriteFile(fullPath, []byte(wf.Content), perm); err != nil {
 		return err
 	}
 
diff --git a/cloudinit/write_file_test.go b/cloudinit/write_file_test.go
index 7111f4a..3e489bf 100644
--- a/cloudinit/write_file_test.go
+++ b/cloudinit/write_file_test.go
@@ -10,9 +10,8 @@ import (
 
 func TestWriteFileUnencodedContent(t *testing.T) {
 	wf := WriteFile{
-		Path:        "/tmp/foo",
-		Content:     "bar",
-		Permissions: "0644",
+		Path:               "/tmp/foo",
+		Content:            "bar",
 	}
 	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
 	if err != nil {
@@ -47,9 +46,9 @@ func TestWriteFileUnencodedContent(t *testing.T) {
 
 func TestWriteFileInvalidPermission(t *testing.T) {
 	wf := WriteFile{
-		Path:        "/tmp/foo",
-		Content:     "bar",
-		Permissions: "pants",
+		Path:               "/tmp/foo",
+		Content:            "bar",
+		RawFilePermissions: "pants",
 	}
 	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
 	if err != nil {
@@ -62,10 +61,37 @@ func TestWriteFileInvalidPermission(t *testing.T) {
 	}
 }
 
+func TestWriteFilePermissions(t *testing.T) {
+	wf := WriteFile{
+		Path:               "/tmp/foo",
+		RawFilePermissions: "0755",
+	}
+	dir, err := ioutil.TempDir(os.TempDir(), "coreos-cloudinit-")
+	if err != nil {
+		t.Fatalf("Unable to create tempdir: %v", err)
+	}
+	defer syscall.Rmdir(dir)
+
+	if err := ProcessWriteFile(dir, &wf); err != nil {
+		t.Fatalf("Processing of WriteFile failed: %v", err)
+	}
+
+	fullPath := path.Join(dir, "tmp", "foo")
+
+	fi, err := os.Stat(fullPath)
+	if err != nil {
+		t.Fatalf("Unable to stat file: %v", err)
+	}
+
+	if fi.Mode() != os.FileMode(0755) {
+		t.Errorf("File has incorrect mode: %v", fi.Mode())
+	}
+}
+
 func TestWriteFileEncodedContent(t *testing.T) {
 	wf := WriteFile{
-		Path: "/tmp/foo",
-		Content: "",
+		Path:     "/tmp/foo",
+		Content:  "",
 		Encoding: "base64",
 	}