the ida scope plugin does a very nice jobb checking crypto.I did a fix for ida 6.1 here http://techbliss.org/threads/idascope-v1-1-yara-scanning-fixed-for-ida-6-1-python-2-7.484/#post-1509
and there is also the RSA key finder script.
http://kyprizel.net/work/ida_rsakeyfinder.html /(python needed)