Are there any very simple RSA implementation in C++

Question

Are there any very simple cross-platform C++ libs which can do assymetric encription? Not necessary efficient, just working. I imagine it could be just 3-4 functions in an .h file which do arbitrary precission math and that's it.

I belive using OpenSSL here is an overkill.

Answer 1

http://cryptopp.com/ looks to be what I need. One might tear it down to individual files, and it has RSA samples.