void *silc_pkcs_get_context(SilcPKCSType type, SilcPublicKey public_key);

    Returns the internal PKCS `type' specific public key context from the
    `public_key'.  The caller needs to explicitly type cast it to correct
    type.  Returns NULL on error.

    For SILC_PKCS_SILC the returned context is SilcSILCPublicKey.