SilcBool silc_auth_verify_data(const unsigned char *payload,
                               SilcUInt32 payload_len,
                               SilcAuthMethod auth_method,
                               const void *auth_data,
                               SilcUInt32 auth_data_len, SilcHash hash,
                               const void *id, SilcIdType type);

    Same as silc_auth_verify but the payload has not been parsed yet.
    Verifies the authentication data directly from the Authentication
    Payload. Supports all authentication methods. If the authentication
    method is passphrase based then the `auth_data' and `auth_data_len'
    are the passphrase and its length.  The passphrase MUST be UTF-8
    encoded.  If the method is public key authentication then the
    `auth_data' is the SilcPublicKey and the `auth_data_len' is ignored.