For DH, use standard primes from RFCs

[exim.git] / src / README.UPDATING

diff --git a/src/README.UPDATING b/src/README.UPDATING
index a15bd418e30f0fe3967e6551376d26bf24dee655..6a820bc7c3254b91021c0d8ff0e1617a26e9e7ba 100644 (file)
--- a/src/README.UPDATING
+++ b/src/README.UPDATING
@@ -142,6 +142,21 @@ Exim version 4.80
    fail completely.  (The check is not done as root, to ensure that problems
    here are not made worse by the check).
 
    fail completely.  (The check is not done as root, to ensure that problems
    here are not made worse by the check).
 

+ * The "tls_dhparam" option has been updated, so that it can now specify a
+   path or an identifier for a standard DH prime from one of a few RFCs.
+   The default for OpenSSL is no longer to not use DH but instead to use
+   one of these standard primes.  The default for GnuTLS is no longer to use
+   a file in the spool directory, but to use that same standard prime.
+   The option is now used by GnuTLS too.  If it points to a path, then
+   GnuTLS will use that path, instead of a file in the spool directory;
+   GnuTLS will attempt to create it if it does not exist.
+
+   To preserve the previous behaviour of generating files in the spool
+   directory, set "tls_dhparam = historic".  Since prior releases of Exim
+   ignored tls_dhparam when using GnuTLS, this can safely be done before
+   the upgrade.
+
+

 
 Exim version 4.77
 -----------------
 
 Exim version 4.77
 -----------------