tls_dh_min_bits smtp transport option

[exim.git] / doc / doc-txt / NewStuff

diff --git a/doc/doc-txt/NewStuff b/doc/doc-txt/NewStuff
index 36b85d1baf7ac5dc2958404022d3e7647851d22f..be8285b679dfee4be5b269a86fee738b44fb7112 100644 (file)
--- a/doc/doc-txt/NewStuff
+++ b/doc/doc-txt/NewStuff
@@ -6,6 +6,32 @@ Before a formal release, there may be quite a lot of detail so that people can
 test from the snapshots or the CVS before the documentation is updated. Once
 the documentation is updated, this file is reduced to a short list.
 
+Version 4.81
+------------
+
+ 1. New command-line option -bI:sieve will list all supported sieve extensions
+    of this Exim build on standard output, one per line.
+    ManageSieve (RFC 5804) providers managing scripts for use by Exim should
+    query this to establish the correct list to include in the protocol's
+    SIEVE capability line.
+
+ 2. If the -n option is combined with the -bP option, then the name of an
+    emitted option is not output, only the value (if visible to you).
+    For instance, "exim -n -bP pid_file_path" should just emit a pathname
+    followed by a newline, and no other text.
+
+ 3. When built with SUPPORT_TLS and USE_GNUTLS, the SMTP transport driver now
+    has a "tls_dh_min_bits" option, to set the minimum acceptable number of
+    bits in the Diffie-Hellman prime offered by a server (in DH ciphersuites)
+    acceptable for security.  (Option accepted but ignored if using OpenSSL).
+    Defaults to 1024, the old value.  May be lowered only to 512, or raised as
+    far as you like.  Raising this may hinder TLS interoperability with other
+    sites and is not currently recommended.  Lowering this will permit you to
+    establish a TLS session which is not as secure as you might like.
+
+    Unless you really know what you are doing, leave it alone.
+
+
 Version 4.80
 ------------
 
@@ -96,6 +122,20 @@ Version 4.80
 
 14. New expansion variable $tod_epoch_l for higher-precision time.
 
+15. New global option tls_dh_max_bits, defaulting to current value of NSS
+    hard-coded limit of DH ephemeral bits, to fix interop problems caused by
+    GnuTLS 2.12 library recommending a bit count higher than NSS supports.
+
+16. tls_dhparam now used by both OpenSSL and GnuTLS, can be path or identifier.
+    Option can now be a path or an identifier for a standard prime.
+    If unset, we use the DH prime from section 2.2 of RFC 5114, "ike23".
+    Set to "historic" to get the old GnuTLS behaviour of auto-generated DH
+    primes.
+
+17. SSLv2 now disabled by default in OpenSSL.  (Never supported by GnuTLS).
+    Use "openssl_options -no_sslv2" to re-enable support, if your OpenSSL
+    install was not built with OPENSSL_NO_SSL2 ("no-ssl2").
+
 
 Version 4.77
 ------------