diff --git a/include/polarssl/x509_crl.h b/include/polarssl/x509_crl.h
index 0fee59b..81d4734 100644
--- a/include/polarssl/x509_crl.h
+++ b/include/polarssl/x509_crl.h
@@ -93,6 +93,9 @@
     x509_buf sig;
     md_type_t sig_md;           /**< Internal representation of the MD algorithm of the signature algorithm, e.g. POLARSSL_MD_SHA256 */
     pk_type_t sig_pk            /**< Internal representation of the Public Key algorithm of the signature algorithm, e.g. POLARSSL_PK_RSA */;
+#if defined(POLARSSL_RSASSA_PSS_CERTIFICATES)
+    x509_buf sig_params;        /**< Parameters for the signature algorithm */
+#endif
 
     struct _x509_crl *next;
 }