diff --git a/include/mbedtls/x509.h b/include/mbedtls/x509.h
index ff06d13..6a6fd02 100644
--- a/include/mbedtls/x509.h
+++ b/include/mbedtls/x509.h
@@ -305,8 +305,9 @@
                      mbedtls_x509_buf *serial );
 int mbedtls_x509_get_ext( unsigned char **p, const unsigned char *end,
                   mbedtls_x509_buf *ext, int tag );
+
 #if !defined(MBEDTLS_X509_REMOVE_INFO)
-int mbedtls_x509_sig_alg_gets( char *buf, size_t size, const mbedtls_x509_buf *sig_oid,
+int mbedtls_x509_sig_alg_gets( char *buf, size_t size,
                        mbedtls_pk_type_t pk_alg, mbedtls_md_type_t md_alg,
                        const void *sig_opts );
 #endif
diff --git a/library/x509.c b/library/x509.c
index aeabdd3..58cd871 100644
--- a/library/x509.c
+++ b/library/x509.c
@@ -841,20 +841,34 @@
 /*
  * Helper for writing signature algorithms
  */
-int mbedtls_x509_sig_alg_gets( char *buf, size_t size, const mbedtls_x509_buf *sig_oid,
-                       mbedtls_pk_type_t pk_alg, mbedtls_md_type_t md_alg,
-                       const void *sig_opts )
+int mbedtls_x509_sig_alg_gets( char *buf, size_t size, mbedtls_pk_type_t pk_alg,
+                               mbedtls_md_type_t md_alg, const void *sig_opts )
 {
     int ret;
     char *p = buf;
     size_t n = size;
     const char *desc = NULL;
+    mbedtls_x509_buf sig_oid;
+    mbedtls_md_type_t tmp_md_alg = md_alg;
 
-    ret = mbedtls_oid_get_sig_alg_desc( sig_oid, &desc );
-    if( ret != 0 )
-        ret = mbedtls_snprintf( p, n, "???"  );
-    else
+#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
+    /* The hash for RSASSA is determined by the algorithm parameters;
+     * in the OID list, the hash is set to MBEDTLS_MD_NONE. */
+    if( pk_alg == MBEDTLS_PK_RSASSA_PSS )
+        tmp_md_alg = MBEDTLS_MD_NONE;
+#endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
+
+    sig_oid.tag = MBEDTLS_ASN1_OID;
+    ret = mbedtls_oid_get_oid_by_sig_alg( pk_alg, tmp_md_alg,
+                                          (const char**) &sig_oid.p,
+                                          &sig_oid.len );
+    if( ret == 0 &&
+        mbedtls_oid_get_sig_alg_desc( &sig_oid, &desc ) == 0 )
+    {
         ret = mbedtls_snprintf( p, n, "%s", desc );
+    }
+    else
+        ret = mbedtls_snprintf( p, n, "???" );
     MBEDTLS_X509_SAFE_SNPRINTF;
 
 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
diff --git a/library/x509_crl.c b/library/x509_crl.c
index 4f5507f..a56d5e3 100644
--- a/library/x509_crl.c
+++ b/library/x509_crl.c
@@ -690,8 +690,8 @@
     ret = mbedtls_snprintf( p, n, "\n%ssigned using  : ", prefix );
     MBEDTLS_X509_SAFE_SNPRINTF;
 
-    ret = mbedtls_x509_sig_alg_gets( p, n, &crl->sig_oid, crl->sig_pk, crl->sig_md,
-                             crl->sig_opts );
+    ret = mbedtls_x509_sig_alg_gets( p, n, crl->sig_pk,
+                                     crl->sig_md, crl->sig_opts );
     MBEDTLS_X509_SAFE_SNPRINTF;
 
     ret = mbedtls_snprintf( p, n, "\n" );
diff --git a/library/x509_crt.c b/library/x509_crt.c
index 9372998..f1f5473 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -1606,8 +1606,8 @@
     ret = mbedtls_snprintf( p, n, "\n%ssigned using      : ", prefix );
     MBEDTLS_X509_SAFE_SNPRINTF;
 
-    ret = mbedtls_x509_sig_alg_gets( p, n, &crt->sig_oid, crt->sig_pk,
-                             crt->sig_md, crt->sig_opts );
+    ret = mbedtls_x509_sig_alg_gets( p, n, sig_info.sig_pk,
+                                     sig_info.sig_md, sig_info.sig_opts );
     MBEDTLS_X509_SAFE_SNPRINTF;
 
     /* Key size */
diff --git a/library/x509_csr.c b/library/x509_csr.c
index aa519fb..d1a2760 100644
--- a/library/x509_csr.c
+++ b/library/x509_csr.c
@@ -357,8 +357,8 @@
     ret = mbedtls_snprintf( p, n, "\n%ssigned using  : ", prefix );
     MBEDTLS_X509_SAFE_SNPRINTF;
 
-    ret = mbedtls_x509_sig_alg_gets( p, n, &csr->sig_oid, csr->sig_pk, csr->sig_md,
-                             csr->sig_opts );
+    ret = mbedtls_x509_sig_alg_gets( p, n, csr->sig_pk,
+                                     csr->sig_md, csr->sig_opts );
     MBEDTLS_X509_SAFE_SNPRINTF;
 
     if( ( ret = mbedtls_x509_key_size_helper( key_size_str, BEFORE_COLON,