diff --git a/include/mbedtls/x509.h b/include/mbedtls/x509.h
index d6db9c6..d9361b3 100644
--- a/include/mbedtls/x509.h
+++ b/include/mbedtls/x509.h
@@ -142,24 +142,26 @@
  *
  * Comments refer to the status for using certificates. Status can be
  * different for writing certificates or reading CRLs or CSRs.
+ *
+ * Those are defined in oid.h as oid.c needs them in a data structure. Since
+ * these were previously defined here, let's have aliases for compatibility.
  */
-#define MBEDTLS_X509_EXT_AUTHORITY_KEY_IDENTIFIER    (1 << 0)
-#define MBEDTLS_X509_EXT_SUBJECT_KEY_IDENTIFIER      (1 << 1)
-#define MBEDTLS_X509_EXT_KEY_USAGE                   (1 << 2)
-#define MBEDTLS_X509_EXT_CERTIFICATE_POLICIES        (1 << 3)
-#define MBEDTLS_X509_EXT_POLICY_MAPPINGS             (1 << 4)
-#define MBEDTLS_X509_EXT_SUBJECT_ALT_NAME            (1 << 5)    /* Supported (DNS) */
-#define MBEDTLS_X509_EXT_ISSUER_ALT_NAME             (1 << 6)
-#define MBEDTLS_X509_EXT_SUBJECT_DIRECTORY_ATTRS     (1 << 7)
-#define MBEDTLS_X509_EXT_BASIC_CONSTRAINTS           (1 << 8)    /* Supported */
-#define MBEDTLS_X509_EXT_NAME_CONSTRAINTS            (1 << 9)
-#define MBEDTLS_X509_EXT_POLICY_CONSTRAINTS          (1 << 10)
-#define MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE          (1 << 11)
-#define MBEDTLS_X509_EXT_CRL_DISTRIBUTION_POINTS     (1 << 12)
-#define MBEDTLS_X509_EXT_INIHIBIT_ANYPOLICY          (1 << 13)
-#define MBEDTLS_X509_EXT_FRESHEST_CRL                (1 << 14)
-
-#define MBEDTLS_X509_EXT_NS_CERT_TYPE                (1 << 16)
+#define MBEDTLS_X509_EXT_AUTHORITY_KEY_IDENTIFIER MBEDTLS_OID_X509_EXT_AUTHORITY_KEY_IDENTIFIER
+#define MBEDTLS_X509_EXT_SUBJECT_KEY_IDENTIFIER   MBEDTLS_OID_X509_EXT_SUBJECT_KEY_IDENTIFIER
+#define MBEDTLS_X509_EXT_KEY_USAGE                MBEDTLS_OID_X509_EXT_KEY_USAGE
+#define MBEDTLS_X509_EXT_CERTIFICATE_POLICIES     MBEDTLS_OID_X509_EXT_CERTIFICATE_POLICIES
+#define MBEDTLS_X509_EXT_POLICY_MAPPINGS          MBEDTLS_OID_X509_EXT_POLICY_MAPPINGS
+#define MBEDTLS_X509_EXT_SUBJECT_ALT_NAME         MBEDTLS_OID_X509_EXT_SUBJECT_ALT_NAME         /* Supported (DNS) */
+#define MBEDTLS_X509_EXT_ISSUER_ALT_NAME          MBEDTLS_OID_X509_EXT_ISSUER_ALT_NAME
+#define MBEDTLS_X509_EXT_SUBJECT_DIRECTORY_ATTRS  MBEDTLS_OID_X509_EXT_SUBJECT_DIRECTORY_ATTRS
+#define MBEDTLS_X509_EXT_BASIC_CONSTRAINTS        MBEDTLS_OID_X509_EXT_BASIC_CONSTRAINTS        /* Supported */
+#define MBEDTLS_X509_EXT_NAME_CONSTRAINTS         MBEDTLS_OID_X509_EXT_NAME_CONSTRAINTS
+#define MBEDTLS_X509_EXT_POLICY_CONSTRAINTS       MBEDTLS_OID_X509_EXT_POLICY_CONSTRAINTS
+#define MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE       MBEDTLS_OID_X509_EXT_EXTENDED_KEY_USAGE
+#define MBEDTLS_X509_EXT_CRL_DISTRIBUTION_POINTS  MBEDTLS_OID_X509_EXT_CRL_DISTRIBUTION_POINTS
+#define MBEDTLS_X509_EXT_INIHIBIT_ANYPOLICY       MBEDTLS_OID_X509_EXT_INIHIBIT_ANYPOLICY
+#define MBEDTLS_X509_EXT_FRESHEST_CRL             MBEDTLS_OID_X509_EXT_FRESHEST_CRL
+#define MBEDTLS_X509_EXT_NS_CERT_TYPE             MBEDTLS_OID_X509_EXT_NS_CERT_TYPE
 
 /*
  * Storage format identifiers