if err != nil {
			return -1, errObjectTampered
		}
		size += int64(partSize)
	}
	return size, nil
}

// DecryptETag decrypts the ETag that is part of given object
// with the given object encryption key.
//
// However, DecryptETag does not try to decrypt the ETag if
// it consists of a 128 bit hex value (32 hex chars) and exactly
// one '-' followed by a 32-bit number.

		ETag:       "",
		ShouldFail: true, // ETag contains multiple: -
	},
}

func TestDecryptETag(t *testing.T) {
	for i, test := range decryptETagTests {
		etag, err := DecryptETag(test.ObjectKey, test.ObjectInfo)
		if err != nil && !test.ShouldFail {
			t.Fatalf("Test %d: should succeed but failed: %v", i, err)
		}
		if err == nil && test.ShouldFail {