/*
 * Copyright (C), 2000-2007 by the monit project group.
 * All Rights Reserved.
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include <config.h>

#include <ctype.h>

#ifdef HAVE_STRING_H
#include <string.h>
#endif

#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif

#include "protocol.h"

/**
 *  A simple 'SSH protocol version exchange' implemetation based on
 *  RFC (http://www.openssh.com/txt/draft-ietf-secsh-transport-14.txt)
 * 
 *  @author Igor Homyakov, <homyakov@altlinux.ru>
 *
 *  @version \$Id: ssh.c,v 1.16 2007/07/25 12:54:33 hauk Exp $
 *
 *  @file
 */
int check_ssh(Socket_T s) {

  char  buf[STRLEN];

  ASSERT(s);
    
  if(!socket_readln(s, buf, sizeof(buf))) {
    LogError("SSH: error receiving identification string -- %s\n", STRERROR);
    return FALSE;
  }
  
  if(! Util_startsWith(buf, "SSH-")) {
    LogError("SSH: protocol error %s", buf);
    return FALSE;
  }

  /* send identification string back to server */
  if(socket_write(s, buf, strlen(buf)) <= 0) {
    LogError("SSH: error sending identification string -- %s\n", STRERROR);
    return FALSE;
  }

  /* Read one extra line to prevent the "Read from socket failed" warning */
  socket_readln(s, buf, sizeof(buf));
   
  return TRUE;
  
}