builder/googlecompute: private key tests

builder/googlecompute/private_key.go

@@ -8,29 +8,35 @@ import (
 	"io/ioutil"
 )
 
-// processPrivateKeyFile.
+// processPrivateKeyFile takes a private key file and an optional passphrase
+// and decodes it to a byte slice.
 func processPrivateKeyFile(privateKeyFile, passphrase string) ([]byte, error) {
 	rawPrivateKeyBytes, err := ioutil.ReadFile(privateKeyFile)
 	if err != nil {
 		return nil, fmt.Errorf("Failed loading private key file: %s", err)
 	}
+
 	PEMBlock, _ := pem.Decode(rawPrivateKeyBytes)
 	if PEMBlock == nil {
 		return nil, fmt.Errorf("%s does not contain a vaild private key", privateKeyFile)
 	}
+
 	if x509.IsEncryptedPEMBlock(PEMBlock) {
 		if passphrase == "" {
 			return nil, errors.New("a passphrase must be specified when using an encrypted private key")
 		}
+
 		decryptedPrivateKeyBytes, err := x509.DecryptPEMBlock(PEMBlock, []byte(passphrase))
 		if err != nil {
 			return nil, fmt.Errorf("Failed decrypting private key: %s", err)
 		}
+
 		b := &pem.Block{
 			Type:  "RSA PRIVATE KEY",
 			Bytes: decryptedPrivateKeyBytes,
 		}
 		return pem.EncodeToMemory(b), nil
 	}
+
 	return rawPrivateKeyBytes, nil
 }

builder/googlecompute/private_key_test.go

@@ -0,0 +1,78 @@
+package googlecompute
+
+import (
+	"crypto/rand"
+	"crypto/x509"
+	"encoding/pem"
+	"io/ioutil"
+	"os"
+	"testing"
+)
+
+func testPrivateKeyFile(t *testing.T) string {
+	tf, err := ioutil.TempFile("", "packer")
+	if err != nil {
+		t.Fatalf("bad: %s", err)
+	}
+	defer tf.Close()
+
+	b := &pem.Block{
+		Type:  "RSA PRIVATE KEY",
+		Bytes: []byte("what"),
+	}
+
+	if err := pem.Encode(tf, b); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	return tf.Name()
+}
+
+func TestProcesssPrivateKeyFile(t *testing.T) {
+	path := testPrivateKeyFile(t)
+	defer os.Remove(path)
+
+	data, err := processPrivateKeyFile(path, "")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if len(data) <= 0 {
+		t.Fatalf("bad: %#v", data)
+	}
+}
+
+func TestProcessPrivateKeyFile_encrypted(t *testing.T) {
+	// Encrypt the file
+	b, err := x509.EncryptPEMBlock(rand.Reader,
+		"RSA PRIVATE KEY",
+		[]byte("what"),
+		[]byte("password"),
+		x509.PEMCipherAES128)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	tf, err := ioutil.TempFile("", "packer")
+	if err != nil {
+		t.Fatalf("bad: %s", err)
+	}
+	defer os.Remove(tf.Name())
+
+	err = pem.Encode(tf, b)
+	tf.Close()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	path := tf.Name()
+
+	// Should have an error with a bad password
+	if _, err := processPrivateKeyFile(path, "bad"); err == nil {
+		t.Fatal("should error")
+	}
+
+	if _, err := processPrivateKeyFile(path, "password"); err != nil {
+		t.Fatalf("bad: %s", err)
+	}
+}