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;