X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/6f313264de6d6f898478db9251700a5b38bf998d..02dfbd5b7af7816959dbd39c1fe628451204e35f:/catsign.1

diff --git a/catsign.1 b/catsign.1
index e762712..3f1cd5e 100644
--- a/catsign.1
+++ b/catsign.1
@@ -243,6 +243,21 @@ algorithm of the
 command (see
 .BR key (1))
 to generate the key.
+.TP
+.B mac
+This uses a symmetric message-authentication algorithm rather than a
+digital signature.  The precise message-authentication scheme used is
+determined by the
+.B mac
+attribute on the key, which defaults to
+.IB hash -hmac
+if unspecified.  Use the
+.B binary
+algorithm of the
+.B key add
+command (see
+.BR key (1))
+to generate the key.
 .PP
 As well as the signature algorithm itself, a hash function is used.
 This is taken from the