Engine_pkcs11 is an implementation of an engine for OpenSSL. It can be
loaded using code, a configuration file, or the command line and passes
any function call by openssl to a PKCS#11 module. Engine_pkcs11 is
meant to be used with smart cards and software for using smart cards in
PKCS#11 format, such as OpenSC. Originally, this engine was part of
OpenSC until OpenSC was split into several small projects to improve
flexibility.