/* ###
 * IP: GHIDRA
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
//XOR's the memory of the current program.
//@category Analysis

import ghidra.app.script.GhidraScript;
import ghidra.program.model.address.*;
import ghidra.program.model.mem.Memory;
import ghidra.program.model.mem.MemoryBlock;

public class XorMemoryScript extends GhidraScript {

	@Override
	public void run() throws Exception {

		// default to the current memory block
		Memory memory = currentProgram.getMemory();
		MemoryBlock block = memory.getBlock(currentAddress);
		AddressSetView set = new AddressSet(block.getStart(), block.getEnd());

		if (currentSelection != null && !currentSelection.isEmpty()) {
			set = currentSelection;
		}

		byte[] xorValues = askBytes("XorValue", "Values to xor with selected memory:");

		int valueLength = xorValues.length;
		int xorIndex = 0;

		AddressIterator aIter = set.getAddresses(true);

		while (aIter.hasNext() && !monitor.isCancelled()) {
			Address addr = aIter.next();
			monitor.setMessage(addr.toString());
			byte xorValue = xorValues[xorIndex];
			byte b = memory.getByte(addr);
			b = (byte) (b ^ xorValue);
			memory.setByte(addr, b);
			xorIndex += 1;
			xorIndex = xorIndex % valueLength;
		}
	}

}