dh_bits);
#endif
+/* Some clients have hard-coded limits. */
+if (dh_bits > tls_dh_max_bits)
+ {
+ DEBUG(D_tls)
+ debug_printf("tls_dh_max_bits clamping override, using %d bits instead.\n",
+ tls_dh_max_bits);
+ dh_bits = tls_dh_max_bits;
+ }
+
if (!string_format(filename, sizeof(filename),
"%s/gnutls-params-%d", spool_directory, dh_bits))
return tls_error(US"overlong filename", NULL, NULL);
m.data = malloc(m.size);
if (m.data == NULL)
return tls_error(US"memory allocation failed", strerror(errno), NULL);
+ /* this will return a size 1 less than the allocation size above; I
+ originally used sz so as to avoid type compatibility errors, as gnutls_datum
+ uses "unsigned int" for the size field, but this call takes separate data
+ and size fields, with the latter being a size_t*. For now, we live with
+ the error as being safer than throwing away type information. */
rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
- m.data, &sz);
+ m.data, &m.size);
if (rc != GNUTLS_E_SUCCESS)
{
free(m.data);
state->tls_certificate = certificate;
state->tls_privatekey = privatekey;
+state->tls_require_ciphers = require_ciphers;
state->tls_sni = sni;
state->tls_verify_certificates = cas;
state->tls_crl = crl;
+/*************************************************
+* Let tls_require_ciphers be checked at startup *
+*************************************************/
+
+/* The tls_require_ciphers option, if set, must be something which the
+library can parse.
+
+Returns: NULL on success, or error message
+*/
+
+uschar *
+tls_validate_require_cipher(void)
+{
+int rc;
+uschar *expciphers = NULL;
+gnutls_priority_t priority_cache;
+const char *errpos;
+
+#define validate_check_rc(Label) do { \
+ if (rc != GNUTLS_E_SUCCESS) { if (exim_gnutls_base_init_done) gnutls_global_deinit(); \
+ return string_sprintf("%s failed: %s", (Label), gnutls_strerror(rc)); } } while (0)
+#define return_deinit(Label) do { gnutls_global_deinit(); return (Label); } while (0)
+
+if (exim_gnutls_base_init_done)
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "already initialised GnuTLS, Exim developer bug");
+
+rc = gnutls_global_init();
+validate_check_rc(US"gnutls_global_init()");
+exim_gnutls_base_init_done = TRUE;
+
+if (!(tls_require_ciphers && *tls_require_ciphers))
+ return_deinit(NULL);
+
+if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers))
+ return_deinit(US"failed to expand tls_require_ciphers");
+
+if (!(expciphers && *expciphers))
+ return_deinit(NULL);
+
+DEBUG(D_tls)
+ debug_printf("tls_require_ciphers expands to \"%s\"\n", expciphers);
+
+rc = gnutls_priority_init(&priority_cache, CS expciphers, &errpos);
+validate_check_rc(string_sprintf(
+ "gnutls_priority_init(%s) failed at offset %ld, \"%.8s..\"",
+ expciphers, errpos - CS expciphers, errpos));
+
+#undef return_deinit
+#undef validate_check_rc
+gnutls_global_deinit();
+
+return NULL;
+}
+
+
+
+
/*************************************************
* Report the library versions. *
*************************************************/