/* -*- c-basic-offset: 8 -*-
   FreeRDP: A Remote Desktop Protocol client.
   ASN.1 Encoding and Decoding

   Copyright (C) Marc-Andre Moreau <marcandre.moreau@gmail.com> 2009

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#ifndef __ASN1_H
#define __ASN1_H

#include "frdp.h"
#include "iso.h"
#include "mcs.h"
#include "chan.h"
#include "secure.h"
#include "rdp.h"
#include "mem.h"
#include "asn1.h"

/* Parse an ASN.1 BER header */
RD_BOOL
ber_parse_header(rdpMcs * mcs, STREAM s, int tagval, int *length)
{
	int tag, len;

	if (tagval > 0xff)
	{
		in_uint16_be(s, tag);
	}
	else
	{
		in_uint8(s, tag);
	}

	if (tag != tagval)
	{
		ui_error(mcs->sec->rdp->inst, "expected tag %d, got %d\n", tagval, tag);
		return False;
	}

	in_uint8(s, len);

	if (len & 0x80)
	{
		len &= ~0x80;
		*length = 0;
		while (len--)
			next_be(s, *length);
	}
	else
		*length = len;

	return s_check(s);
}

/* Output an ASN.1 BER header */
void
ber_out_header(STREAM s, int tagval, int length)
{
	if (tagval > 0xff)
	{
		out_uint16_be(s, tagval);
	}
	else
	{
		out_uint8(s, tagval);
	}

	if (length >= 0x80)
	{
		out_uint8(s, 0x82);
		out_uint16_be(s, length);
	}
	else
		out_uint8(s, length);
}

/* Output an ASN.1 BER integer */
void
ber_out_integer(STREAM s, int value)
{
	ber_out_header(s, BER_TAG_INTEGER, 2);
	out_uint16_be(s, value);
}

#endif /* __ASN1_H */