X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/ba96c15acada57f6ee24be266256d606dae53e26..f1e05cc79778c693a1a2bad478ced44791922cce:/doc/doc-docbook/spec.xfpt

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 8afccbf1d..9c39b4aa2 100644
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -11824,6 +11824,16 @@ command in a filter file. Its use is explained in the description of that
 command, which can be found in the separate document entitled &'Exim's
 interfaces to mail filtering'&.
 
+.new
+.vitem &$tls_bits$&
+.vindex "&$tls_bits$&"
+Contains an approximation of the TLS cipher's bit-strength; the meaning of
+this depends upon the TLS implementation used.
+If TLS has not been negotiated, the value will be 0.
+The value of this is automatically fed into the Cyrus SASL authenticator
+when acting as a server, to specify the "external SSF" (a SASL term).
+.wen
+
 .vitem &$tls_certificate_verified$&
 .vindex "&$tls_certificate_verified$&"
 This variable is set to &"1"& if a TLS certificate was verified when the