GnuTLS: avoid whining about OCSP when not requested by config

[exim.git] / src / src / tls-gnu.c

diff --git a/src/src/tls-gnu.c b/src/src/tls-gnu.c
index 6db7e4a8cf25a014e59c24752f4e0dffcd169e7f..fe180946b1e5db891cb38d40ef7abb7552b80003 100644 (file)
--- a/src/src/tls-gnu.c
+++ b/src/src/tls-gnu.c
@@ -2,7 +2,7 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) University of Cambridge 1995 - 2014 */
+/* Copyright (c) University of Cambridge 1995 - 2015 */
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Copyright (c) Phil Pennock 2012 */
@@ -176,6 +176,10 @@ static const char * const exim_default_gnutls_priority = "NORMAL";
 
 static BOOL exim_gnutls_base_init_done = FALSE;
 
+#ifndef DISABLE_OCSP
+static BOOL gnutls_buggy_ocsp = FALSE;
+#endif
+
 
 /* ------------------------------------------------------------------------ */
 /* macros */
@@ -831,18 +835,25 @@ if (  !host       /* server */
    && tls_ocsp_file
    )
   {
-  if (!expand_check(tls_ocsp_file, US"tls_ocsp_file",
-       &state->exp_tls_ocsp_file))
-    return DEFER;
+  if (gnutls_buggy_ocsp)
+    {
+    DEBUG(D_tls) debug_printf("GnuTLS library is buggy for OCSP; avoiding\n");
+    }
+  else
+    {
+    if (!expand_check(tls_ocsp_file, US"tls_ocsp_file",
+         &state->exp_tls_ocsp_file))
+      return DEFER;
 
-  /* Use the full callback method for stapling just to get observability.
-  More efficient would be to read the file once only, if it never changed
-  (due to SNI). Would need restart on file update, or watch datestamp.  */
+    /* Use the full callback method for stapling just to get observability.
+    More efficient would be to read the file once only, if it never changed
+    (due to SNI). Would need restart on file update, or watch datestamp.  */
 
-  gnutls_certificate_set_ocsp_status_request_function(state->x509_cred,
-    server_ocsp_stapling_cb, state->exp_tls_ocsp_file);
+    gnutls_certificate_set_ocsp_status_request_function(state->x509_cred,
+      server_ocsp_stapling_cb, state->exp_tls_ocsp_file);
 
-  DEBUG(D_tls) debug_printf("Set OCSP response file %s\n", &state->exp_tls_ocsp_file);
+    DEBUG(D_tls) debug_printf("OCSP response file = %s\n", state->exp_tls_ocsp_file);
+    }
   }
 #endif
 
@@ -1011,6 +1022,38 @@ return OK;
 *            Initialize for GnuTLS               *
 *************************************************/
 
+
+#ifndef DISABLE_OCSP
+
+static BOOL
+tls_is_buggy_ocsp(void)
+{
+const uschar * s;
+uschar maj, mid, mic;
+
+s = CUS gnutls_check_version(NULL);
+maj = atoi(CCS s);
+if (maj == 3)
+  {
+  while (*s && *s != '.') s++;
+  mid = atoi(CCS ++s);
+  if (mid <= 2)
+    return TRUE;
+  else if (mid >= 5)
+    return FALSE;
+  else
+    {
+    while (*s && *s != '.') s++;
+    mic = atoi(CCS ++s);
+    return mic <= (mid == 3 ? 16 : 3);
+    }
+  }
+return FALSE;
+}
+
+#endif
+
+
 /* Called from both server and client code. In the case of a server, errors
 before actual TLS negotiation return DEFER.
 
@@ -1074,6 +1117,11 @@ if (!exim_gnutls_base_init_done)
     }
 #endif
 
+#ifndef DISABLE_OCSP
+  if (tls_ocsp_file && (gnutls_buggy_ocsp = tls_is_buggy_ocsp()))
+    log_write(0, LOG_MAIN, "OCSP unusable with this GnuTLS library version");
+#endif
+
   exim_gnutls_base_init_done = TRUE;
   }