diff --git a/keystore/user_state.h b/keystore/user_state.h
index b0671e3..620aaa5 100644
--- a/keystore/user_state.h
+++ b/keystore/user_state.h
@@ -75,14 +75,14 @@
     bool operator<(uid_t userId) const;
 
   private:
-    static const int SHA1_DIGEST_SIZE_BYTES = 16;
-    static const int SHA256_DIGEST_SIZE_BYTES = 32;
+    static constexpr int SHA1_DIGEST_SIZE_BYTES = 16;
+    static constexpr int SHA256_DIGEST_SIZE_BYTES = 32;
 
-    static const int MASTER_KEY_SIZE_BYTES = SHA256_DIGEST_SIZE_BYTES;
-    static const int MASTER_KEY_SIZE_BITS = MASTER_KEY_SIZE_BYTES * 8;
+    static constexpr int MASTER_KEY_SIZE_BYTES = kAes256KeySizeBytes;
+    static constexpr int MASTER_KEY_SIZE_BITS = MASTER_KEY_SIZE_BYTES * 8;
 
-    static const int MAX_RETRY = 4;
-    static const size_t SALT_SIZE = 16;
+    static constexpr int MAX_RETRY = 4;
+    static constexpr size_t SALT_SIZE = 16;
 
     void generateKeyFromPassword(std::vector<uint8_t>& key, const android::String8& pw,
                                  uint8_t* salt);