Subversion Repositories ao486

/*

 * Copyright (c) 2014, Aleksander Osman

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 * * Redistributions of source code must retain the above copyright notice, this

 *   list of conditions and the following disclaimer.

 *

 * * Redistributions in binary form must reproduce the above copyright notice,

 *   this list of conditions and the following disclaimer in the documentation

 *   and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER

 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,

 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

package ao486.test.layers;

import java.util.HashMap;

import java.util.LinkedList;

import java.util.Random;

public class StackLayer extends Layer {

    public StackLayer(Random random, LinkedList<Pair<Long, Long>> prohibited_list) {

        this.random = random;

        ss_d_b = random.nextBoolean();

        while(true) {

            ss_base = norm(random.nextInt());

            ss_limit = random.nextInt(ss_d_b? 0xFFFFF + 1 : 0xFFFF + 1);

            if( ss_base + ss_limit < 4294967296L &&

                collides(prohibited_list, ss_base, ss_base + ss_limit) == false

            ) break;

        }

        esp = random.nextInt((int)ss_limit + 1);

        ss_index = ss_base + esp;

        if(ss_d_b == false) {

            esp |= random.nextInt() & 0xFFFF0000;

        }

        prohibited_list.add(new Pair<>(ss_base, ss_base+ss_limit));

    }

    public void push_byte(int value) {

//System.out.printf("push_byte: %08x :: %08x\n", ss_index, value);

        if(ss_index > ss_base + ss_limit) return;

        ss_map.put(ss_index, (byte)(value & 0xFF));

        ss_index++;

    }

    public void push_word(int value) {

//System.out.printf("push_word: %08x :: %08x\n", ss_index, value);

        if(ss_index > ss_base + ss_limit) return;

        ss_map.put(ss_index, (byte)(value & 0xFF));

        ss_index++;

        if(ss_index > ss_base + ss_limit) return;

        ss_map.put(ss_index, (byte)((value >> 8) & 0xFF));

        ss_index++;

    }

    public void push_dword(int value) {

//System.out.printf("push_dword: %08x :: %08x\n", ss_index, value);

        if(ss_index > ss_base + ss_limit) return;

        ss_map.put(ss_index, (byte)(value & 0xFF));

        ss_index++;

        if(ss_index > ss_base + ss_limit) return;

        ss_map.put(ss_index, (byte)((value >> 8) & 0xFF));

        ss_index++;

        if(ss_index > ss_base + ss_limit) return;

        ss_map.put(ss_index, (byte)((value >> 16) & 0xFF));

        ss_index++;

        if(ss_index > ss_base + ss_limit) return;

        ss_map.put(ss_index, (byte)((value >> 24) & 0xFF));

        ss_index++;

    }

    //-----------

    public long esp() {

        return esp;

    }

    public long ss_base() {

        return ss_base;

    }

    public long ss_limit() {

        return ss_limit;

    }

    public long ss_d_b() {

        return ss_d_b? 1 : 0;

    }

    public boolean is_memory_not_random(long address) { return ss_map.containsKey(address); }

    public Byte get_memory(long address) {

        if(address < ss_base || address > ss_base + ss_limit) return null;

        if(ss_map.containsKey(address)) return ss_map.get(address);

        return (byte)random.nextInt();

    }

    HashMap<Long, Byte> ss_map = new HashMap<>();

    boolean ss_d_b;

    long ss_base, ss_limit, ss_index;

    long esp;

}