diff --git a/ssl-ca b/ssl-ca
index 7097cb20e31f69cb5f31a0fb2c2c406e6f7434a4..38e21e91a6d4eb38cb20c3bd38864994989007e6 100755
--- a/ssl-ca
+++ b/ssl-ca
@@ -1,5 +1,6 @@
 #!/bin/sh -e
 
+test $(which openssl) || ( echo "Can't find openssl."; exit 1)
 export domain="$(basename $PWD)"
 seed="$(hexdump -n10 -e '10/1 "%02o" "\n"' /dev/urandom)"
 config=\