/*
Copyright (C) 2011-2013 de4dot@gmail.com
This file is part of de4dot.
de4dot 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.
de4dot 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 de4dot. If not, see .
*/
using System;
using System.Collections.Generic;
using dnlib.DotNet.Emit;
namespace de4dot.blocks.cflow {
// If a block is just a dup followed by a bcc, try to append the block
// to all its sources. Will fix some SA assemblies.
class DupBlockCflowDeobfuscator : BlockDeobfuscator {
protected override bool deobfuscate(Block block) {
if (block.Instructions.Count != 2)
return false;
if (block.Instructions[0].OpCode.Code != Code.Dup)
return false;
if (!block.LastInstr.isConditionalBranch() && block.LastInstr.OpCode.Code != Code.Switch)
return false;
bool modified = false;
foreach (var source in new List(block.Sources)) {
if (source.getOnlyTarget() != block)
continue;
if (!source.canAppend(block))
continue;
source.append(block);
modified = true;
}
return modified;
}
}
}