parse.h

/* parse.h
 *
 * Parses the data formats used in ssh packets.
 *
 * $Id$ */

/* lsh, an implementation of the ssh protocol
 *
 * Copyright (C) 1998 Niels Möller
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifndef LSH_PARSE_H_INCLUDED
#define LSH_PARSE_H_INCLUDED

#include "atoms.h"
#include "bignum.h"


/* Simple buffer
 * NOTE: All instances are allocated on the stack.
 * No object header is needed. */

struct simple_buffer
{
  UINT32 capacity;
  UINT32 pos;
  UINT8 *data;
};

void simple_buffer_init(struct simple_buffer *buffer,
			UINT32 capacity, UINT8 *data);

/* Returns 1 on success, 0 on failure */
int parse_uint32(struct simple_buffer *buffer, UINT32 *result);

/* Only records length and start pointer */
int parse_string(struct simple_buffer *buffer,
		 UINT32 *length, UINT8 **start);

/* Copies a given number of octets, without any length header */
int parse_octets(struct simple_buffer *buffer,
		 UINT32 length, UINT8 *start);

/* Copies a substring */
struct lsh_string *parse_string_copy(struct simple_buffer *buffer);

/* Initializes subbuffer to parse a string from buffer */
int parse_sub_buffer(struct simple_buffer *buffer,
		     struct simple_buffer *subbuffer);

int parse_uint8(struct simple_buffer *buffer, unsigned *result);

/* Returns 1 on success, 0 on error, and -1 at end of buffer */
int parse_utf8(struct simple_buffer *buffer, UINT32 *result);

int parse_boolean(struct simple_buffer *buffer, int *result);

int parse_bignum(struct simple_buffer *buffer, mpz_t result);

int parse_atom(struct simple_buffer *buffer, UINT32 *result);

/* Returns 1 on success, 0 on failure, and -1 at end of buffer.
 * Unknown atoms sets result to zero. */
int parse_next_atom(struct simple_buffer *buffer, UINT32 *result);

/* Reads a list of atoms. The buffer should hold the list body; the
 * length field should already be stripped off (usually by
 * parse_sub_buffer()). */
struct int_list *parse_atoms(struct simple_buffer *buffer, unsigned limit);

/* Creates a list of integers. The 0 atom means an unknown atom was
 * read. Returns a NULL pointer on error. */
struct int_list *parse_atom_list(struct simple_buffer *buffer, unsigned limit);

/* Returns success (i.e. 1) iff there is no data left */
int parse_eod(struct simple_buffer *buffer);

#endif /* LSH_PARSE_H_INCLUDED */