SilcBool silc_pkcs1_encode(SilcPkcs1BlockType bt,
                               const unsigned char *data,
                               SilcUInt32 data_len,
                               unsigned char *dest_data,
                               SilcUInt32 dest_data_size,
                               SilcRng rng);

    Encodes PKCS#1 data block from the `data' according to the block type
    indicated by `bt'.  When encoding signatures the `bt' must be
    SILC_PKCS1_BT_PRV1 and when encoding encryption blocks the `bt' must
    be SILC_PKCS1_BT_PUB.  The encoded data is copied into the `dest_data'
    buffer which is size of `dest_data_size'.  If the `dest_data' is not
    able to hold the encoded block this returns FALSE.  Usually the
    `dest_data_size' is set to the RSA key length value as it is the
    length of one block.  The `rng' should be set when `bt' is set to
    SILC_PKCS1_BT_PUB.  If `rng' is NULL global RNG is used.  This
    function returns TRUE on success.