-static uschar txt[256];
-size_t sz = sizeof(txt);
-return ( gnutls_x509_crt_get_dn(cert, CS txt, &sz) == 0 )
- ? string_copy(txt) : NULL;
+uschar * cp = NULL;
+int ret;
+size_t siz = 0;
+
+ret = gnutls_x509_crt_get_dn(cert, cp, &siz);
+if (ret != GNUTLS_E_SHORT_MEMORY_BUFFER)
+ {
+ fprintf(stderr, "%s: gs0 fail: %s\n", __FUNCTION__, gnutls_strerror(ret));
+ return NULL;
+ }
+
+cp = store_get(siz);
+
+ret = gnutls_x509_crt_get_dn(cert, cp, &siz);
+if (ret < 0)
+ {
+ fprintf(stderr, "%s: gs1 fail: %s\n", __FUNCTION__, gnutls_strerror(ret));
+ return NULL;
+ }
+
+return cp;