monocul.us/de4dot-cex
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Fix code branching to dup/bcc blocks.

Browse Source
This commit is contained in:
de4dot 2012-12-21 13:55:57 +01:00
parent d91f82f0c1
commit cade446d21
3 changed files with 51 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
blocks/blocks.csproj
View File

@ -48,6 +48,7 @@
<Compile Include="cflow\ConstantsFolder.cs" />
<Compile Include="cflow\DeadCodeRemover.cs" />
<Compile Include="cflow\DeadStoreRemover.cs" />
<Compile Include="cflow\DupBlockDeobfuscator.cs" />
<Compile Include="cflow\IBlocksDeobfuscator.cs" />
<Compile Include="cflow\ICflowDeobfuscator.cs" />
<Compile Include="cflow\InstructionEmulator.cs" />

1
blocks/cflow/BlocksCflowDeobfuscator.cs
View File

@ -43,6 +43,7 @@ namespace de4dot.blocks.cflow {
ourBlocksDeobfuscators.Add(new DeadCodeRemover { ExecuteOnNoChange = false });
ourBlocksDeobfuscators.Add(new ConstantsFolder { ExecuteOnNoChange = true });
ourBlocksDeobfuscators.Add(new StLdlocFixer { ExecuteOnNoChange = true });
ourBlocksDeobfuscators.Add(new DupBlockCflowDeobfuscator { ExecuteOnNoChange = true });
}
public void add(IEnumerable<IBlocksDeobfuscator> blocksDeobfuscators) {

49
blocks/cflow/DupBlockDeobfuscator.cs Normal file
View File

@ -0,0 +1,49 @@
/*
Copyright (C) 2011-2012 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 <http://www.gnu.org/licenses/>.
*/
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>(block.Sources)) {
if (source.getOnlyTarget() != block)
continue;
if (!source.canAppend(block))
continue;
source.append(block);
modified = true;
}
return modified;
}
}
}