Make unused method stuff simpler don't worry about collisions, I'll

rename everything later so it wont be a problem
This commit is contained in:
Adam
2015-07-05 21:05:34 -04:00
parent bfcfaa84e6
commit fcc8fddcd7
4 changed files with 194 additions and 151 deletions

View File

@@ -3,4 +3,11 @@
<groupId>info.sigterm</groupId>
<artifactId>deob</artifactId>
<version>0.0.1-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-collections4</artifactId>
<version>4.0</version>
</dependency>
</dependencies>
</project>

View File

@@ -62,7 +62,7 @@ public class Deob
new UnusedFields().run(group);
new ModularArithmeticDeobfuscation().run(group);
//new ModularArithmeticDeobfuscation().run(group);
saveJar(group, args[1]);

View File

@@ -30,7 +30,7 @@ public class Method
private short accessFlags;
private String name;
private Signature arguments;
public Signature arguments;
private Attributes attributes;
Method(Methods methods) throws IOException
@@ -60,89 +60,6 @@ public class Method
{
//assert callsFrom.isEmpty();
}
public void removeParameter(Execution execution, int paramIndex, int lvtIndex)
{
Set<Instruction> done = new HashSet<>();
for (Frame f : execution.processedFrames)
for (InstructionContext ins : f.getInstructions())
if (ins.getInvokes().contains(this))
{
int pops = arguments.size() - paramIndex - 1; // index from top of stack of parameter
ins.removeStack(pops); // remove parameter from stack
if (done.contains(ins.getInstruction()))
continue;
InvokeInstruction iins = (InvokeInstruction) ins.getInstruction();
iins.removeParameter(paramIndex); // remove parameter from instruction
done.add(ins.getInstruction());
}
// this double checks that all calls to this have been located
for (ClassFile cf : methods.getClassFile().getGroup().getClasses())
for (Method m : cf.getMethods().getMethods())
{
Code c = m.getCode();
if (c == null)
continue;
for (Instruction i : c.getInstructions().getInstructions())
{
if (i instanceof InvokeInstruction)
{
InvokeInstruction ii = (InvokeInstruction) i;
PoolEntry pool = ii.getMethod();
if (pool instanceof info.sigterm.deob.pool.Method)
{
info.sigterm.deob.pool.Method pm = (info.sigterm.deob.pool.Method) pool;
if (pm.getClassEntry().getName().equals(this.getMethods().getClassFile().getName()) && pm.getNameAndType().equals(this.getNameAndType()) && !done.contains(i))
{
// for some reason this wasn't removed above?
System.err.println("Method " + m.getName() + " in " + cf.getName() + " calls " + pm.getNameAndType().getName() + " in " + pm.getClassEntry().getName() + " at " + i.getPc() + ", but this instruction was not found during execution");
//assert false;
}
}
else if (pool instanceof info.sigterm.deob.pool.InterfaceMethod)
{
info.sigterm.deob.pool.InterfaceMethod pm = (info.sigterm.deob.pool.InterfaceMethod) pool;
if (pm.getClassEntry().getName().equals(this.getMethods().getClassFile().getName()) && pm.getNameAndType().equals(this.getNameAndType()) && !done.contains(i))
{
// for some reason this wasn't removed above?
System.err.println("Method " + m.getName() + " in " + cf.getName() + " calls " + pm.getNameAndType().getName() + " in " + pm.getClassEntry().getName() + " at " + i.getPc() + ", but this instruction was not found during execution");
//assert false;
}
}
}
}
}
// adjust lvt indexes to get rid of idx in the method
for (Instruction ins : new ArrayList<>(getCode().getInstructions().getInstructions()))
{
if (ins instanceof LVTInstruction)
{
LVTInstruction lins = (LVTInstruction) ins;
int i = lins.getVariableIndex();
assert i != lvtIndex; // current unused variable detection just looks for no accesses
// reassign
if (i > lvtIndex)
{
Instruction newIns = lins.setVariableIndex(--i);
if (newIns != ins)
ins.replace(newIns);
}
}
}
arguments.remove(paramIndex);
}
public Methods getMethods()
{

View File

@@ -3,16 +3,25 @@ package info.sigterm.deob.deobfuscators;
import info.sigterm.deob.ClassFile;
import info.sigterm.deob.ClassGroup;
import info.sigterm.deob.Method;
import info.sigterm.deob.attributes.Code;
import info.sigterm.deob.attributes.code.Instruction;
import info.sigterm.deob.attributes.code.instruction.types.InvokeInstruction;
import info.sigterm.deob.attributes.code.instruction.types.LVTInstruction;
import info.sigterm.deob.execution.Execution;
import info.sigterm.deob.execution.Frame;
import info.sigterm.deob.execution.InstructionContext;
import info.sigterm.deob.pool.NameAndType;
import info.sigterm.deob.pool.PoolEntry;
import info.sigterm.deob.signature.Signature;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.apache.commons.collections4.CollectionUtils;
public class UnusedParameters
{
private static List<Method> findDependentMethods(NameAndType nat, Set<ClassFile> visited, ClassGroup group, ClassFile cf)
@@ -24,8 +33,8 @@ public class UnusedParameters
visited.add(cf);
Method method = cf.findMethod(nat);
if (method != null)
Method method = cf.findMethod(nat); // XXX this searches down
if (method != null && !method.isStatic())
list.add(method);
// search parent
@@ -45,7 +54,147 @@ public class UnusedParameters
private static List<Method> findDependentMethods(Method m)
{
ClassFile cf = m.getMethods().getClassFile();
return findDependentMethods(m.getNameAndType(), new HashSet<ClassFile>(), cf.getGroup(), cf);
List<Method> methods = findDependentMethods(m.getNameAndType(), new HashSet<ClassFile>(), cf.getGroup(), cf);
Set s = new HashSet<>(methods); // XXX
return new ArrayList<>(s);
}
private List<Integer> findUnusedParameters(Method method)
{
int offset = method.isStatic() ? 0 : 1;
Signature signature = method.getNameAndType().getDescriptor();
List<Integer> unusedParams = new ArrayList<>();
for (int variableIndex = 0, lvtIndex = offset;
variableIndex < signature.size();
lvtIndex += signature.getTypeOfArg(variableIndex++).getSlots())
{
List<? extends Instruction> lv = method.findLVTInstructionsForVariable(lvtIndex);
if (lv == null || lv.isEmpty())
unusedParams.add(variableIndex);
}
return unusedParams;
}
private int[] getLvtIndexes(Signature signature, int offset)
{
int[] i = new int[signature.size()];
for (int variableIndex = 0, lvtIndex = offset;
variableIndex < signature.size();
lvtIndex += signature.getTypeOfArg(variableIndex++).getSlots())
{
i[variableIndex] = lvtIndex;
}
return i;
}
private Collection<Integer> findUnusedParameters(Collection<Method> methods)
{
Collection<Integer> list = null;
for (Method m : methods)
{
List<Integer> p = findUnusedParameters(m);
if (list == null)
list = p;
else
list = CollectionUtils.intersection(list, p);
}
return list;
}
public void removeParameter(List<Method> methods, Signature signature, Execution execution, int paramIndex, int lvtIndex)
{
Set<Instruction> done = new HashSet<>();
for (Frame f : execution.processedFrames)
for (InstructionContext ins : f.getInstructions())
if (!ins.getInvokes().isEmpty() && methods.containsAll(ins.getInvokes()))
{
System.out.println("Removing from " + ins);
int pops = signature.size() - paramIndex - 1; // index from top of stack of parameter
ins.removeStack(pops); // remove parameter from stack
if (done.contains(ins.getInstruction()))
continue;
InvokeInstruction iins = (InvokeInstruction) ins.getInstruction();
iins.removeParameter(paramIndex); // remove parameter from instruction
done.add(ins.getInstruction());
}
/*
// this double checks that all calls to this have been located
for (ClassFile cf : method.getMethods().getClassFile().getGroup().getClasses())
for (Method m : cf.getMethods().getMethods())
{
Code c = m.getCode();
if (c == null)
continue;
for (Instruction i : c.getInstructions().getInstructions())
{
if (i instanceof InvokeInstruction)
{
InvokeInstruction ii = (InvokeInstruction) i;
PoolEntry pool = ii.getMethod();
if (pool instanceof info.sigterm.deob.pool.Method)
{
info.sigterm.deob.pool.Method pm = (info.sigterm.deob.pool.Method) pool;
if (pm.getClassEntry().getName().equals(method.getMethods().getClassFile().getName()) && pm.getNameAndType().equals(method.getNameAndType()) && !done.contains(i))
{
// for some reason this wasn't removed above?
System.err.println("Method " + m.getName() + " in " + cf.getName() + " calls " + pm.getNameAndType().getName() + " in " + pm.getClassEntry().getName() + " at " + i.getPc() + ", but this instruction was not found during execution");
//assert false;
}
}
else if (pool instanceof info.sigterm.deob.pool.InterfaceMethod)
{
info.sigterm.deob.pool.InterfaceMethod pm = (info.sigterm.deob.pool.InterfaceMethod) pool;
if (pm.getClassEntry().getName().equals(method.getMethods().getClassFile().getName()) && pm.getNameAndType().equals(method.getNameAndType()) && !done.contains(i))
{
// for some reason this wasn't removed above?
System.err.println("Method " + m.getName() + " in " + cf.getName() + " calls " + pm.getNameAndType().getName() + " in " + pm.getClassEntry().getName() + " at " + i.getPc() + ", but this instruction was not found during execution");
//assert false;
}
}
}
}
}
*/
for (Method method : methods)
if (method.getCode() != null)
// adjust lvt indexes to get rid of idx in the method
for (Instruction ins : new ArrayList<>(method.getCode().getInstructions().getInstructions()))
{
if (ins instanceof LVTInstruction)
{
LVTInstruction lins = (LVTInstruction) ins;
int i = lins.getVariableIndex();
assert i != lvtIndex; // current unused variable detection just looks for no accesses
// reassign
if (i > lvtIndex)
{
Instruction newIns = lins.setVariableIndex(--i);
if (newIns != ins)
ins.replace(newIns);
}
}
}
for (Method method : methods)
method.arguments.remove(paramIndex);
}
private int[] checkParametersOnce(Execution execution, ClassGroup group)
@@ -54,81 +203,55 @@ public class UnusedParameters
// if more than one is unused, we'll just remove the one
// and do the others on another pass
Set<Method> done = new HashSet<>();
int count = 0;
int collide = 0;
int overrides = 0;
//group.buildCallGraph(); // method.removeParameter uses the callgraph
for (ClassFile cf : group.getClasses())
{
for (Method m : cf.getMethods().getMethods())
{
if (done.contains(m))
continue;
int offset = m.isStatic() ? 0 : 1;
Signature signature = m.getNameAndType().getDescriptor();
// for a parameter to be unused it must be unused on all methods that override it
List<Method> methods = findDependentMethods(m); // these are all of the methods the param must be unused in
assert methods.contains(m);
List<Method> methods;
if (!m.isStatic())
{
methods = findDependentMethods(m); // these are all of the methods the param must be unused in
}
else
{
methods = new ArrayList<>();
methods.add(m);
}
if (methods.size() > 1)
continue; // don't mess with this now
Collection<Integer> unusedParameters = findUnusedParameters(methods);
if (m.getCode() == null)
if (unusedParameters.isEmpty())
continue;
outer:
for (int variableIndex = 0, lvtIndex = offset;
variableIndex < signature.size();
lvtIndex += signature.getTypeOfArg(variableIndex++).getSlots())
{
for (Method method : methods)
{
// XXX instead of checking if the lvt index is never accessed,
// check execution frames and see if it is never read prior to being
// written to, and if so, then remove the parameter, but don't re index
// the lvt table.
List<? extends Instruction> lv = method.findLVTInstructionsForVariable(lvtIndex);
if (lv != null && !lv.isEmpty())
continue outer; // used, try next parameter
}
/*if (lv == null)
continue;
// XXX instead of checking if the lvt index is never accessed,
// check execution frames and see if it is never read prior to being
// written to, and if so, then remove the parameter, but don't re index
// the lvt table.
if (!lv.isEmpty())
continue;
if (!m.getOverriddenMethods().isEmpty())
{
++overrides;
continue;
}*/
Signature newSig = new Signature(m.getDescriptor());
newSig.remove(variableIndex);
Method otherMethod = cf.getMethods().findMethod(new NameAndType(m.getName(), newSig));
if (otherMethod != null)
{
// sometimes removing an unused parameter will cause a signature collision with another function,
// just ignore it atm (there seems to be very few)
++collide;
continue;
}
m.removeParameter(execution, variableIndex, lvtIndex);
++count;
break;
}
int unusedParameter = (int) unusedParameters.toArray()[0];
int[] lvtIndexes = getLvtIndexes(signature, offset);
for (Method m2 : methods)
done.add(m2);
/* removing the parameter can cause collision of overriden methods,
* we should first rename all methods to be unique?
*/
System.out.println("Removing " + m.getName() + " on " + m.getMethods().getClassFile().getName());
removeParameter(methods, signature, execution, unusedParameter, lvtIndexes[unusedParameter]);
++count;
break;
}
}
return new int[] { count, collide, overrides };
return new int[] { count };
}
public void run(ClassGroup group)
@@ -138,19 +261,15 @@ public class UnusedParameters
execution.run();
int count = 0;
int collide = 0;
int override = 0;
int[] i;
do
{
i = checkParametersOnce(execution, group);
count += i[0];
collide = i[1]; // the next pass may be able to reduce the collisions
override = i[2];
}
while (i[0] > 0);
System.out.println("Removed " + count + " unused parameters, unable to remove " + collide + " because of signature collisions and " + override + " due to overriding");
System.out.println("Removed " + count + " unused parameters");
}
}