crypto GnuPG is a complete and free replacement for PGP. Because it does not use the patented IDEA algorithm, it can be used without any restrictions. GnuPG is a RFC2440 (OpenPGP) compliant application. Bring in dev-libs/libusb as a dependency; enable scdaemon. Build scdaemon software. Enables usage of OpenPGP cards. For other type of smartcards, try app-crypt/gnupg-pkcs11-scd. Build direct CCID access for scdaemon; requires dev-libs/libusb. Build mta support using virtual/mta.