untrusted comment: signature from openbsd 6.0 base secret key
RWSho3oKSqgLQ/cNueHXB60QopDDgrfL27XGOqkV4wf7x5Nchi8V7ib8bbDxQuk71xVUcPPNkZoGUXvJlxYh/mlfBm//OVs9ggA=

OpenBSD 6.0 errata 6, Sept 17, 2016:

During parsing of the iked(8) configuration, a variable is set to 0 by
mistake, disabling Pre-Shared key authentication.

Apply by doing:
   signify -Vep /etc/signify/openbsd-60-base.pub -x 006_iked.patch.sig \
       -m - | (cd /usr/src && patch -p0)

And then rebuild and install iked:
   cd /usr/src/sbin/iked
   make obj
   make depend
   make
   make install

Index: sbin/iked/parse.y
===================================================================
RCS file: /cvs/src/sbin/iked/parse.y,v
retrieving revision 1.56
diff -u -p -r1.56 parse.y
--- sbin/iked/parse.y   20 Jul 2016 12:31:00 -0000      1.56
+++ sbin/iked/parse.y   14 Sep 2016 22:31:03 -0000
@@ -823,7 +823,6 @@ ikeauth             : /* empty */                   {
                       memcpy(&$$, &$2, sizeof($$));
                       $$.auth_method = IKEV2_AUTH_SHARED_KEY_MIC;
                       $$.auth_eap = 0;
-                       $$.auth_length = 0;
               }
               | EAP STRING                    {
                       unsigned int i;