Wrap creation of CryptoConfig in constructors

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>

cmd/ctr/commands/images/decrypt.go

@@ -88,11 +88,8 @@ var decryptCommand = cli.Command{
 			return err
 		}
 
-		cc := &encconfig.CryptoConfig{
+		cc := encconfig.InitDecryption(dcparameters)
-			DecryptConfig: &encconfig.DecryptConfig{
+
-				Parameters: dcparameters,
-			},
-		}
 		_, err = decryptImage(client, ctx, local, newName, cc, layers32, context.StringSlice("platform"))
 
 		return err

cmd/ctr/commands/images/encrypt.go

@@ -133,14 +133,8 @@ var encryptCommand = cli.Command{
 		dcparameters["privkeys-passwords"] = privKeysPasswords
 		dcparameters["x509s"] = decX509s
 
-		cc := &encconfig.CryptoConfig{
+		cc := encconfig.InitEncryption(parameters, dcparameters)
-			EncryptConfig: &encconfig.EncryptConfig{
+
-				Parameters: parameters,
-				DecryptConfig: encconfig.DecryptConfig{
-					Parameters: dcparameters,
-				},
-			},
-		}
 		_, err = encryptImage(client, ctx, local, newName, cc, layers32, context.StringSlice("platform"))
 
 		return err

image_enc_test.go

@@ -129,14 +129,7 @@ func TestImageEncryption(t *testing.T) {
 	dcparameters["privkeys"] = [][]byte{privateKey}
 	dcparameters["privkeys-passwords"] = [][]byte{{}}
 
-	cc := &encconfig.CryptoConfig{
+	cc := encconfig.InitEncryption(parameters, dcparameters)
-		EncryptConfig: &encconfig.EncryptConfig{
-			Parameters: parameters,
-			DecryptConfig: encconfig.DecryptConfig{
-				Parameters: dcparameters,
-			},
-		},
-	}
 
 	// Perform encryption of image
 	encSpec, modified, err := imgenc.EncryptImage(ctx, client.ContentStore(), image.Target, cc, lf)
@@ -156,11 +149,8 @@ func TestImageEncryption(t *testing.T) {
 		t.Fatalf("Unable to create image: %v", err)
 	}
 
-	cc = &encconfig.CryptoConfig{
+	cc = encconfig.InitDecryption(dcparameters)
-		DecryptConfig: &encconfig.DecryptConfig{
+
-			Parameters: dcparameters,
-		},
-	}
 	// Clean up function cancels lease before deleting the image so the images are
 	// properly deleted
 	defer func() {

images/encryption/encryption.go

@@ -415,15 +415,13 @@ func DecryptImage(ctx context.Context, cs content.Store, desc ocispec.Descriptor
 // It takes decrypting of the layers only as far as decrypting the asymmetrically encrypted data
 // The decryption is only done for the current platform
 func CheckAuthorization(ctx context.Context, cs content.Store, desc ocispec.Descriptor, dc *encconfig.DecryptConfig) error {
-	cc := encconfig.CryptoConfig{
+	cc := encconfig.InitDecryption(dc.Parameters)
-		DecryptConfig: dc,
-	}
 
 	lf := func(desc ocispec.Descriptor) bool {
 		return true
 	}
 
-	_, _, err := cryptImage(ctx, cs, desc, &cc, lf, cryptoOpUnwrapOnly)
+	_, _, err := cryptImage(ctx, cs, desc, cc, lf, cryptoOpUnwrapOnly)
 	if err != nil {
 		return errors.Wrapf(err, "you are not authorized to use this image")
 	}

pkg/encryption/config/config.go

@@ -38,3 +38,26 @@ type CryptoConfig struct {
 	EncryptConfig *EncryptConfig
 	DecryptConfig *DecryptConfig
 }
+
+// InitDecryption initialized a CryptoConfig object with parameters used for decryption
+func InitDecryption(dcparameters map[string][][]byte) *CryptoConfig {
+	return &CryptoConfig{
+		DecryptConfig: &DecryptConfig{
+			Parameters: dcparameters,
+		},
+	}
+}
+
+// InitEncryption initializes a CryptoConfig object with parameters used for encryption
+// It also takes dcparameters that may be needed for decryption when adding a recipient
+// to an already encrypted image
+func InitEncryption(parameters, dcparameters map[string][][]byte) *CryptoConfig {
+	return &CryptoConfig{
+		EncryptConfig: &EncryptConfig{
+			Parameters: parameters,
+			DecryptConfig: DecryptConfig{
+				Parameters: dcparameters,
+			},
+		},
+	}
+}