1 files changed, 121 insertions, 0 deletions
diff --git a/regress/hostkey-rotate.sh b/regress/hostkey-rotate.sh
new file mode 100644
index 0000000..c3e100c
--- /dev/null
+++ b/regress/hostkey-rotate.sh
@@ -0,0 +1,121 @@
+#	$OpenBSD: hostkey-rotate.sh,v 1.8 2019/11/26 23:43:10 djm Exp $
+#	Placed in the Public Domain.
+
+tid="hostkey rotate"
+
+rm -f $OBJ/hkr.* $OBJ/ssh_proxy.orig
+
+grep -vi 'hostkey' $OBJ/sshd_proxy > $OBJ/sshd_proxy.orig
+echo "UpdateHostkeys=yes" >> $OBJ/ssh_proxy
+rm $OBJ/known_hosts
+
+# The "primary" key type is ed25519 since it's supported even when built
+# without OpenSSL.  The secondary is RSA if it's supported.
+primary="ssh-ed25519"
+secondary="$primary"
+
+trace "prepare hostkeys"
+nkeys=0
+all_algs=""
+for k in $SSH_HOSTKEY_TYPES; do
+	${SSHKEYGEN} -qt $k -f $OBJ/hkr.$k -N '' || fatal "ssh-keygen $k"
+	echo "Hostkey $OBJ/hkr.${k}" >> $OBJ/sshd_proxy.orig
+	nkeys=`expr $nkeys + 1`
+	test "x$all_algs" = "x" || all_algs="${all_algs},"
+	all_algs="${all_algs}$k"
+	case "$k" in
+		ssh-rsa)	secondary="ssh-rsa" ;;
+	esac
+done
+
+dossh() {
+	# All ssh should succeed in this test
+	${SSH} -F $OBJ/ssh_proxy "$@" x true || fail "ssh $@ failed"
+}
+
+expect_nkeys() {
+	_expected=$1
+	_message=$2
+	_n=`wc -l $OBJ/known_hosts | awk '{ print $1 }'` || fatal "wc failed"
+	[ "x$_n" = "x$_expected" ] || fail "$_message (got $_n wanted $_expected)"
+}
+
+check_key_present() {
+	_type=$1
+	_kfile=$2
+	test "x$_kfile" = "x" && _kfile="$OBJ/hkr.${_type}.pub"
+	_kpub=`awk "/$_type /"' { print $2 }' < $_kfile` || \
+		fatal "awk failed"
+	fgrep "$_kpub" $OBJ/known_hosts > /dev/null
+}
+
+cp $OBJ/sshd_proxy.orig $OBJ/sshd_proxy
+
+# Connect to sshd with StrictHostkeyChecking=no
+verbose "learn hostkey with StrictHostKeyChecking=no"
+>$OBJ/known_hosts
+dossh -oHostKeyAlgorithms=$primary -oStrictHostKeyChecking=no
+# Verify no additional keys learned
+expect_nkeys 1 "unstrict connect keys"
+check_key_present $primary || fail "unstrict didn't learn key"
+
+# Connect to sshd as usual
+verbose "learn additional hostkeys"
+dossh -oStrictHostKeyChecking=yes -oHostKeyAlgorithms=$all_algs
+# Check that other keys learned
+expect_nkeys $nkeys "learn hostkeys"
+for k in $SSH_HOSTKEY_TYPES; do
+	check_key_present $k || fail "didn't learn keytype $k"
+done
+
+# Check each key type
+for k in $SSH_HOSTKEY_TYPES; do
+	verbose "learn additional hostkeys, type=$k"
+	dossh -oStrictHostKeyChecking=yes -oHostKeyAlgorithms=$k,$all_algs
+	expect_nkeys $nkeys "learn hostkeys $k"
+	check_key_present $k || fail "didn't learn $k correctly"
+done
+
+# Change one hostkey (non primary) and relearn
+if [ "$primary" != "$secondary" ]; then
+	verbose "learn changed non-primary hostkey type=${secondary}"
+	mv $OBJ/hkr.${secondary}.pub $OBJ/hkr.${secondary}.pub.old
+	rm -f $OBJ/hkr.${secondary}
+	${SSHKEYGEN} -qt ${secondary} -f $OBJ/hkr.${secondary} -N '' || \
+	    fatal "ssh-keygen $secondary"
+	dossh -oStrictHostKeyChecking=yes -oHostKeyAlgorithms=$all_algs
+	# Check that the key was replaced
+	expect_nkeys $nkeys "learn hostkeys"
+	check_key_present ${secondary} $OBJ/hkr.${secondary}.pub.old && \
+	    fail "old key present"
+	check_key_present ${secondary} || fail "didn't learn changed key"
+fi
+
+# Add new hostkey (primary type) to sshd and connect
+verbose "learn new primary hostkey"
+${SSHKEYGEN} -qt ${primary} -f $OBJ/hkr.${primary}-new -N '' || fatal "ssh-keygen ed25519"
+( cat $OBJ/sshd_proxy.orig ; echo HostKey $OBJ/hkr.${primary}-new ) \
+    > $OBJ/sshd_proxy
+# Check new hostkey added
+dossh -oStrictHostKeyChecking=yes -oHostKeyAlgorithms=${primary},$all_algs
+expect_nkeys `expr $nkeys + 1` "learn hostkeys"
+check_key_present ${primary} || fail "current key missing"
+check_key_present ${primary} $OBJ/hkr.${primary}-new.pub || fail "new key missing"
+
+# Remove old hostkey (primary type) from sshd
+verbose "rotate primary hostkey"
+cp $OBJ/sshd_proxy.orig $OBJ/sshd_proxy
+mv $OBJ/hkr.${primary}.pub $OBJ/hkr.${primary}.pub.old
+mv $OBJ/hkr.${primary}-new.pub $OBJ/hkr.${primary}.pub
+mv $OBJ/hkr.${primary}-new $OBJ/hkr.${primary}
+# Check old hostkey removed
+dossh -oStrictHostKeyChecking=yes -oHostKeyAlgorithms=${primary},$all_algs
+expect_nkeys $nkeys "learn hostkeys"
+check_key_present ${primary} $OBJ/hkr.${primary}.pub.old && fail "old key present"
+check_key_present ${primary} || fail "didn't learn changed key"
+
+# Connect again, forcing rotated key
+verbose "check rotate primary hostkey"
+dossh -oStrictHostKeyChecking=yes -oHostKeyAlgorithms=${primary}
+expect_nkeys 1 "learn hostkeys"
+check_key_present ${primary} || fail "didn't learn changed key"