private void processExitBranchesIter(CfgManipulator cfgManipulator, GraphRandomStateGenerator randomStateGenerator, MethodCfg originalMethodCfg, MethodCfg methodCfg, BasicBlock startBasicBlock, LocalDefinition intStateLocal, LocalDefinition currentNodeLocal) {
int currentValidPathId;
// create a list of basic blocks that still have to be processed by the algorithm
List<BasicBlock> basicBlocksToProcess = new List<BasicBlock>(methodCfg.basicBlocks);
System.Console.WriteLine("Basic Blocks to process (Control Flow): " + basicBlocksToProcess.Count());
while (true) {
List<BasicBlock> copiedList = new List<BasicBlock>(basicBlocksToProcess);
foreach (BasicBlock currentBasicBlock in copiedList) {
// get the metadata for the current basic block
GraphTransformerMetadataBasicBlock metadata = null;
for (int i = 0; i < currentBasicBlock.transformationMetadata.Count(); i++) {
// get graph transformer metadata for basic blocks
if ((currentBasicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock) == null) {
continue;
}
metadata = (currentBasicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock);
break;
}
if (metadata == null) {
throw new ArgumentException("Not able to find metadata for current basic block.");
}
// remove currently processed basic block from the list of basic blocks to process
basicBlocksToProcess.Remove(currentBasicBlock);
// check if the current exit branch is of type "no branch target"
if (currentBasicBlock.exitBranch as NoBranchTarget != null) {
NoBranchTarget introBranch = (NoBranchTarget)currentBasicBlock.exitBranch;
// search for all semantically equal basic blocks in the modified method CFG (as possible targets)
int searchSementicId = introBranch.takenTarget.semanticId;
List<BasicBlock> possibleTargetBasicBlocks = new List<BasicBlock>();
if (searchSementicId != -1) {
foreach (BasicBlock searchBasicBlock in methodCfg.basicBlocks) {
if (searchBasicBlock.semanticId == searchSementicId) {
possibleTargetBasicBlocks.Add(searchBasicBlock);
}
}
if (possibleTargetBasicBlocks.Count() == 0) {
throw new ArgumentException("Not able to find any semantically equal basic block in CFG.");
}
}
else {
possibleTargetBasicBlocks.Add(introBranch.takenTarget);
}
// create a list of target basic blocks of this branch
List<Target> listOfTargets = new List<Target>();
Target target = new Target();
target.basicBlock = introBranch.takenTarget;
listOfTargets.Add(target);
// generate code for the "state switch"
BasicBlock stateBasicBlock = null;
SwitchBranchTarget stateExitBranch = null;
this.createCodeStateSwitch(ref stateBasicBlock, ref stateExitBranch, intStateLocal, metadata.correspondingGraphNodes);
cfgManipulator.insertBasicBlockBetweenBranch(introBranch, stateBasicBlock, stateExitBranch, 0);
// create for each valid path a branch in the switch statement of the "state switch"
for (currentValidPathId = 0; currentValidPathId < this.graph.graphValidPathCount; currentValidPathId++) {
// ignore first valid path (with id 0)
// => add artificial branch to original branch target (for the current valid path id)
if (currentValidPathId != 0) {
// fill switch taken branch list with null when index is out of range
while (stateExitBranch.takenTarget.Count() <= currentValidPathId) {
stateExitBranch.takenTarget.Add(null);
}
// randomly chose what the target of the current branch should be (weight to use an existing basic block to have less memory consumption)
switch (this.prng.Next(this.duplicateBasicBlockWeight)) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// duplicate the target basic block
BasicBlock duplicatedBasicBlock = this.duplicateBasicBlock(originalMethodCfg, methodCfg, listOfTargets.ElementAt(0).basicBlock);
methodCfg.basicBlocks.Add(duplicatedBasicBlock);
basicBlocksToProcess.Add(duplicatedBasicBlock);
// add new basic block as target of the switch case
stateExitBranch.takenTarget[currentValidPathId] = duplicatedBasicBlock;
duplicatedBasicBlock.entryBranches.Add(stateExitBranch);
// add new basic block to the list of target basic blocks
target = new Target();
target.basicBlock = duplicatedBasicBlock;
listOfTargets.Add(target);
// add duplicated basic block to the list of possible target basic blocks
possibleTargetBasicBlocks.Add(duplicatedBasicBlock);
// create metadata for the newly created basic block
if (!createAndAddMetadata(duplicatedBasicBlock)) {
throw new ArgumentException("Creating metadata for the duplicated basic block failed.");
}
break;
}
default: {
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock newTarget = possibleTargetBasicBlocks.ElementAt(randPosition);
target = new Target();
target.basicBlock = newTarget;
listOfTargets.Add(target);
// set switch taken branch for current valid path id to the chosen branch target
stateExitBranch.takenTarget[currentValidPathId] = target.basicBlock;
target.basicBlock.entryBranches.Add(stateExitBranch);
break;
}
}
}
// set current valid path id of the target
target.currentValidPathId = currentValidPathId;
// get the link from the current basic block to the obfuscation graph
BasicBlockGraphNodeLink currentGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in metadata.correspondingGraphNodes) {
if (tempLink.validPathId == currentValidPathId) {
currentGraphLink = tempLink;
break;
}
}
if (currentGraphLink == null) {
throw new ArgumentNullException("Could not find link from current basic block to the graph for the given path id.");
}
// get the metadata for the target basic block
GraphTransformerMetadataBasicBlock targetMetadata = null;
for (int i = 0; i < target.basicBlock.transformationMetadata.Count(); i++) {
// get graph transformer metadata for basic blocks
if ((target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock) == null) {
continue;
}
targetMetadata = (target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock);
break;
}
if (targetMetadata == null) {
throw new ArgumentException("Not able to find metadata for target basic block.");
}
// get the link from the target basic block to the obfuscation graph
BasicBlockGraphNodeLink targetGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in targetMetadata.correspondingGraphNodes) {
if (tempLink.validPathId == currentValidPathId) {
targetGraphLink = tempLink;
break;
}
}
if (targetGraphLink == null) {
throw new ArgumentNullException("Could not find link from target basic block to the graph for the given path id.");
}
// choose randomly to either just correct the pointer position or to inject a "state change"
switch (this.prng.Next(this.stateChangeWeight)) {
// case: "state change"
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// generate code for the "state change"
BasicBlock stateChangeBasicBlock = null;
SwitchBranchTarget stateChangeExitBranch = null;
this.createCodeStateChange(ref stateChangeBasicBlock, ref stateChangeExitBranch, randomStateGenerator, currentGraphLink, intStateLocal);
cfgManipulator.insertBasicBlockBetweenBranch(stateExitBranch, currentValidPathId, stateChangeBasicBlock, stateChangeExitBranch, 0);
// create for each valid path a branch in the switch statement of the "state change"
for (int changedCurrentValidPathId = 0; changedCurrentValidPathId < this.graph.graphValidPathCount; changedCurrentValidPathId++) {
// ignore first valid path (with id 0)
// => add artificial branch to original branch target (for the changed current valid path id)
if (changedCurrentValidPathId != 0) {
// fill switch taken branch list with null when index is out of range
while (stateChangeExitBranch.takenTarget.Count() <= changedCurrentValidPathId) {
stateChangeExitBranch.takenTarget.Add(null);
}
// randomly chose what the target of the current branch should be (weight to use an existing basic block to have less memory consumption)
switch (this.prng.Next(this.duplicateBasicBlockWeight)) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// duplicate the target basic block
BasicBlock duplicatedBasicBlock = this.duplicateBasicBlock(originalMethodCfg, methodCfg, listOfTargets.ElementAt(0).basicBlock);
methodCfg.basicBlocks.Add(duplicatedBasicBlock);
basicBlocksToProcess.Add(duplicatedBasicBlock);
// add new basic block as target of the switch case
stateChangeExitBranch.takenTarget[changedCurrentValidPathId] = duplicatedBasicBlock;
duplicatedBasicBlock.entryBranches.Add(stateChangeExitBranch);
// add new basic block to the list of target basic blocks
target = new Target();
target.basicBlock = duplicatedBasicBlock;
listOfTargets.Add(target);
// add duplicated basic block to the list of possible target basic blocks
possibleTargetBasicBlocks.Add(duplicatedBasicBlock);
// create metadata for the newly created basic block
if (!createAndAddMetadata(duplicatedBasicBlock)) {
throw new ArgumentException("Creating metadata for the duplicated basic block failed.");
}
break;
}
default: {
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock newTarget = possibleTargetBasicBlocks.ElementAt(randPosition);
target = new Target();
target.basicBlock = newTarget;
listOfTargets.Add(target);
// set switch taken branch for current valid path id to the chosen branch target
stateChangeExitBranch.takenTarget[changedCurrentValidPathId] = target.basicBlock;
target.basicBlock.entryBranches.Add(stateChangeExitBranch);
break;
}
}
}
// set current valid path id of the target
target.currentValidPathId = changedCurrentValidPathId;
// get the metadata for the change target basic block
GraphTransformerMetadataBasicBlock changeTargetMetadata = null;
for (int i = 0; i < target.basicBlock.transformationMetadata.Count(); i++) {
// get graph transformer metadata for basic blocks
if ((target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock) == null) {
continue;
}
changeTargetMetadata = (target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock);
break;
}
if (changeTargetMetadata == null) {
throw new ArgumentException("Not able to find metadata for target basic block.");
}
// get the link from the change target basic block to the obfuscation graph
BasicBlockGraphNodeLink changeTargetGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in changeTargetMetadata.correspondingGraphNodes) {
if (tempLink.validPathId == changedCurrentValidPathId) {
changeTargetGraphLink = tempLink;
break;
}
}
if (changeTargetGraphLink == null) {
throw new ArgumentNullException("Could not find link from target basic block to the graph for the given path id.");
}
// correct the pointer position to the obfuscation graph
this.injectLinkMoveCode(cfgManipulator, currentGraphLink, changeTargetGraphLink, stateChangeExitBranch, changedCurrentValidPathId, currentNodeLocal);
// if debugging is activated => dump method cfg and add code to dump current graph
if (this.debugging) {
List<IOperation> debugOperations = new List<IOperation>();
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingNumber.ToString().PadLeft(3, '0') + "_" + target.basicBlock.id.ToString() + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method)));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldloc, currentNodeLocal));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.debuggingDumpGraphMethod));
target.basicBlock.operations.InsertRange(0, debugOperations);
//this.logger.dumpMethodCfg(methodCfg, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method));
this.debuggingNumber++;
}
}
break;
}
// case: correct pointer position
default: {
this.injectLinkMoveCode(cfgManipulator, currentGraphLink, targetGraphLink, stateExitBranch, currentGraphLink.validPathId, currentNodeLocal);
// if debugging is activated => dump method cfg and add code to dump current graph
if (this.debugging) {
List<IOperation> debugOperations = new List<IOperation>();
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingNumber.ToString().PadLeft(3, '0') + "_" + target.basicBlock.id.ToString() + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method)));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldloc, currentNodeLocal));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.debuggingDumpGraphMethod));
target.basicBlock.operations.InsertRange(0, debugOperations);
//this.logger.dumpMethodCfg(methodCfg, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method));
this.debuggingNumber++;
}
break;
}
}
}
}
// check if the current exit branch is of type "unconditional branch target"
else if (currentBasicBlock.exitBranch as UnconditionalBranchTarget != null) {
UnconditionalBranchTarget introBranch = (UnconditionalBranchTarget)currentBasicBlock.exitBranch;
// search for all semantically equal basic blocks in the modified method CFG (as possible targets)
int searchSementicId = introBranch.takenTarget.semanticId;
List<BasicBlock> possibleTargetBasicBlocks = new List<BasicBlock>();
if (searchSementicId != -1) {
foreach (BasicBlock searchBasicBlock in methodCfg.basicBlocks) {
if (searchBasicBlock.semanticId == searchSementicId) {
possibleTargetBasicBlocks.Add(searchBasicBlock);
}
}
if (possibleTargetBasicBlocks.Count() == 0) {
throw new ArgumentException("Not able to find any semantically equal basic block in CFG.");
}
}
else {
possibleTargetBasicBlocks.Add(introBranch.takenTarget);
}
// create a list of target basic blocks of this branch
List<Target> listOfTargets = new List<Target>();
Target target = new Target();
target.basicBlock = introBranch.takenTarget;
listOfTargets.Add(target);
// generate code for the "state switch"
BasicBlock stateBasicBlock = null;
SwitchBranchTarget stateExitBranch = null;
this.createCodeStateSwitch(ref stateBasicBlock, ref stateExitBranch, intStateLocal, metadata.correspondingGraphNodes);
cfgManipulator.insertBasicBlockBetweenBranch(introBranch, stateBasicBlock, stateExitBranch, 0);
// create for each valid path a branch in the switch statement of the "state switch"
for (currentValidPathId = 0; currentValidPathId < this.graph.graphValidPathCount; currentValidPathId++) {
// ignore first valid path (with id 0)
// => add artificial branch to original branch target (for the current valid path id)
if (currentValidPathId != 0) {
// fill switch taken branch list with null when index is out of range
while (stateExitBranch.takenTarget.Count() <= currentValidPathId) {
stateExitBranch.takenTarget.Add(null);
}
// randomly chose what the target of the current branch should be (weight to use an existing basic block to have less memory consumption)
switch (this.prng.Next(this.duplicateBasicBlockWeight)) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// duplicate the target basic block
BasicBlock duplicatedBasicBlock = this.duplicateBasicBlock(originalMethodCfg, methodCfg, listOfTargets.ElementAt(0).basicBlock);
methodCfg.basicBlocks.Add(duplicatedBasicBlock);
basicBlocksToProcess.Add(duplicatedBasicBlock);
// add new basic block as target of the switch case
stateExitBranch.takenTarget[currentValidPathId] = duplicatedBasicBlock;
duplicatedBasicBlock.entryBranches.Add(stateExitBranch);
// add new basic block to the list of target basic blocks
target = new Target();
target.basicBlock = duplicatedBasicBlock;
listOfTargets.Add(target);
// add duplicated basic block to the list of possible target basic blocks
possibleTargetBasicBlocks.Add(duplicatedBasicBlock);
// create metadata for the newly created basic block
if (!createAndAddMetadata(duplicatedBasicBlock)) {
throw new ArgumentException("Creating metadata for the duplicated basic block failed.");
}
break;
}
default: {
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock newTarget = possibleTargetBasicBlocks.ElementAt(randPosition);
target = new Target();
target.basicBlock = newTarget;
listOfTargets.Add(target);
//set switch taken branch for current valid path id to the chosen branch target
stateExitBranch.takenTarget[currentValidPathId] = target.basicBlock;
target.basicBlock.entryBranches.Add(stateExitBranch);
break;
}
}
}
// set current valid path id of the target
target.currentValidPathId = currentValidPathId;
// get the link from the current basic block to the obfuscation graph
BasicBlockGraphNodeLink currentGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in metadata.correspondingGraphNodes) {
if (tempLink.validPathId == currentValidPathId) {
currentGraphLink = tempLink;
break;
}
}
if (currentGraphLink == null) {
throw new ArgumentNullException("Could not find link from current basic block to the graph for the given path id.");
}
// get the metadata for the target basic block
GraphTransformerMetadataBasicBlock targetMetadata = null;
for (int i = 0; i < target.basicBlock.transformationMetadata.Count(); i++) {
// get graph transformer metadata for basic blocks
if ((target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock) == null) {
continue;
}
targetMetadata = (target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock);
break;
}
if (targetMetadata == null) {
throw new ArgumentException("Not able to find metadata for target basic block.");
}
// get the link from the target basic block to the obfuscation graph
BasicBlockGraphNodeLink targetGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in targetMetadata.correspondingGraphNodes) {
if (tempLink.validPathId == currentValidPathId) {
targetGraphLink = tempLink;
break;
}
}
if (targetGraphLink == null) {
throw new ArgumentNullException("Could not find link from target basic block to the graph for the given path id.");
}
// choose randomly to either just correct the pointer position or to inject a "state change"
switch (this.prng.Next(this.stateChangeWeight)) {
// case: "state change"
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// generate code for the "state change"
BasicBlock stateChangeBasicBlock = null;
SwitchBranchTarget stateChangeExitBranch = null;
this.createCodeStateChange(ref stateChangeBasicBlock, ref stateChangeExitBranch, randomStateGenerator, currentGraphLink, intStateLocal);
cfgManipulator.insertBasicBlockBetweenBranch(stateExitBranch, currentValidPathId, stateChangeBasicBlock, stateChangeExitBranch, 0);
// create for each valid path a branch in the switch statement of the "state change"
for (int changedCurrentValidPathId = 0; changedCurrentValidPathId < this.graph.graphValidPathCount; changedCurrentValidPathId++) {
// ignore first valid path (with id 0)
// => add artificial branch to original branch target (for the changed current valid path id)
if (changedCurrentValidPathId != 0) {
// fill switch taken branch list with null when index is out of range
while (stateChangeExitBranch.takenTarget.Count() <= changedCurrentValidPathId) {
stateChangeExitBranch.takenTarget.Add(null);
}
// randomly chose what the target of the current branch should be (weight to use an existing basic block to have less memory consumption)
switch (this.prng.Next(this.duplicateBasicBlockWeight)) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// duplicate the target basic block
BasicBlock duplicatedBasicBlock = this.duplicateBasicBlock(originalMethodCfg, methodCfg, listOfTargets.ElementAt(0).basicBlock);
methodCfg.basicBlocks.Add(duplicatedBasicBlock);
basicBlocksToProcess.Add(duplicatedBasicBlock);
// add new basic block as target of the switch case
stateChangeExitBranch.takenTarget[changedCurrentValidPathId] = duplicatedBasicBlock;
duplicatedBasicBlock.entryBranches.Add(stateChangeExitBranch);
// add new basic block to the list of target basic blocks
target = new Target();
target.basicBlock = duplicatedBasicBlock;
listOfTargets.Add(target);
// add duplicated basic block to the list of possible target basic blocks
possibleTargetBasicBlocks.Add(duplicatedBasicBlock);
// create metadata for the newly created basic block
if (!createAndAddMetadata(duplicatedBasicBlock)) {
throw new ArgumentException("Creating metadata for the duplicated basic block failed.");
}
break;
}
default: {
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock newTarget = possibleTargetBasicBlocks.ElementAt(randPosition);
target = new Target();
target.basicBlock = newTarget;
listOfTargets.Add(target);
// set switch taken branch for current valid path id to the chosen branch target
stateChangeExitBranch.takenTarget[changedCurrentValidPathId] = target.basicBlock;
target.basicBlock.entryBranches.Add(stateChangeExitBranch);
break;
}
}
}
// set current valid path id of the target
target.currentValidPathId = changedCurrentValidPathId;
// get the metadata for the change target basic block
GraphTransformerMetadataBasicBlock changeTargetMetadata = null;
for (int i = 0; i < target.basicBlock.transformationMetadata.Count(); i++) {
// get graph transformer metadata for basic blocks
if ((target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock) == null) {
continue;
}
changeTargetMetadata = (target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock);
break;
}
if (changeTargetMetadata == null) {
throw new ArgumentException("Not able to find metadata for target basic block.");
}
// get the link from the change target basic block to the obfuscation graph
BasicBlockGraphNodeLink changeTargetGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in changeTargetMetadata.correspondingGraphNodes) {
if (tempLink.validPathId == changedCurrentValidPathId) {
changeTargetGraphLink = tempLink;
break;
}
}
if (changeTargetGraphLink == null) {
throw new ArgumentNullException("Could not find link from target basic block to the graph for the given path id.");
}
// correct the pointer position to the obfuscation graph
this.injectLinkMoveCode(cfgManipulator, currentGraphLink, changeTargetGraphLink, stateChangeExitBranch, changedCurrentValidPathId, currentNodeLocal);
// if debugging is activated => dump method cfg and add code to dump current graph
if (this.debugging) {
List<IOperation> debugOperations = new List<IOperation>();
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingNumber.ToString().PadLeft(3, '0') + "_" + target.basicBlock.id.ToString() + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method)));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldloc, currentNodeLocal));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.debuggingDumpGraphMethod));
target.basicBlock.operations.InsertRange(0, debugOperations);
//this.logger.dumpMethodCfg(methodCfg, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method));
this.debuggingNumber++;
}
}
break;
}
// case: correct pointer position
default: {
this.injectLinkMoveCode(cfgManipulator, currentGraphLink, targetGraphLink, stateExitBranch, currentGraphLink.validPathId, currentNodeLocal);
// if debugging is activated => dump method cfg and add code to dump current graph
if (this.debugging) {
List<IOperation> debugOperations = new List<IOperation>();
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingNumber.ToString().PadLeft(3, '0') + "_" + target.basicBlock.id.ToString() + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method)));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldloc, currentNodeLocal));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.debuggingDumpGraphMethod));
target.basicBlock.operations.InsertRange(0, debugOperations);
//this.logger.dumpMethodCfg(methodCfg, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method));
this.debuggingNumber++;
}
break;
}
}
}
}
// check if the current exit branch is of type "conditional branch target"
else if (currentBasicBlock.exitBranch as ConditionalBranchTarget != null) {
ConditionalBranchTarget introBranch = (ConditionalBranchTarget)currentBasicBlock.exitBranch;
// search for all semantically equal basic blocks in the modified method CFG (as possible targets)
int searchSementicId = introBranch.takenTarget.semanticId;
List<BasicBlock> possibleTargetBasicBlocks = new List<BasicBlock>();
if (searchSementicId != -1) {
foreach (BasicBlock searchBasicBlock in methodCfg.basicBlocks) {
if (searchBasicBlock.semanticId == searchSementicId) {
possibleTargetBasicBlocks.Add(searchBasicBlock);
}
}
if (possibleTargetBasicBlocks.Count() == 0) {
throw new ArgumentException("Not able to find any semantically equal basic block in CFG.");
}
}
else {
possibleTargetBasicBlocks.Add(introBranch.takenTarget);
}
// create a list of target basic blocks of this branch
List<Target> listOfTargets = new List<Target>();
Target target = new Target();
target.basicBlock = introBranch.takenTarget;
listOfTargets.Add(target);
// generate code for the "state switch"
BasicBlock stateBasicBlock = null;
SwitchBranchTarget stateExitBranch = null;
this.createCodeStateSwitch(ref stateBasicBlock, ref stateExitBranch, intStateLocal, metadata.correspondingGraphNodes);
cfgManipulator.insertBasicBlockBetweenBranch(introBranch, true, stateBasicBlock, stateExitBranch, 0);
// create for each valid path a branch in the switch statement of the "state switch"
for (currentValidPathId = 0; currentValidPathId < this.graph.graphValidPathCount; currentValidPathId++) {
// ignore first valid path (with id 0)
// => add artificial branch to original branch target (for the current valid path id)
if (currentValidPathId != 0) {
// fill switch taken branch list with null when index is out of range
while (stateExitBranch.takenTarget.Count() <= currentValidPathId) {
stateExitBranch.takenTarget.Add(null);
}
// randomly chose what the target of the current branch should be (weight to use an existing basic block to have less memory consumption)
switch (this.prng.Next(this.duplicateBasicBlockWeight)) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// duplicate the target basic block
BasicBlock duplicatedBasicBlock = this.duplicateBasicBlock(originalMethodCfg, methodCfg, listOfTargets.ElementAt(0).basicBlock);
methodCfg.basicBlocks.Add(duplicatedBasicBlock);
basicBlocksToProcess.Add(duplicatedBasicBlock);
// add new basic block as target of the switch case
stateExitBranch.takenTarget[currentValidPathId] = duplicatedBasicBlock;
duplicatedBasicBlock.entryBranches.Add(stateExitBranch);
// add new basic block to the list of target basic blocks
target = new Target();
target.basicBlock = duplicatedBasicBlock;
listOfTargets.Add(target);
// add duplicated basic block to the list of possible target basic blocks
possibleTargetBasicBlocks.Add(duplicatedBasicBlock);
// create metadata for the newly created basic block
if (!createAndAddMetadata(duplicatedBasicBlock)) {
throw new ArgumentException("Creating metadata for the duplicated basic block failed.");
}
break;
}
default: {
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock newTarget = possibleTargetBasicBlocks.ElementAt(randPosition);
target = new Target();
target.basicBlock = newTarget;
listOfTargets.Add(target);
//set switch taken branch for current valid path id to the chosen branch target
stateExitBranch.takenTarget[currentValidPathId] = target.basicBlock;
target.basicBlock.entryBranches.Add(stateExitBranch);
break;
}
}
}
// set current valid path id of the target
target.currentValidPathId = currentValidPathId;
// get the link from the current basic block to the obfuscation graph
BasicBlockGraphNodeLink currentGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in metadata.correspondingGraphNodes) {
if (tempLink.validPathId == currentValidPathId) {
currentGraphLink = tempLink;
break;
}
}
if (currentGraphLink == null) {
throw new ArgumentNullException("Could not find link from current basic block to the graph for the given path id.");
}
// get the metadata for the target basic block
GraphTransformerMetadataBasicBlock targetMetadata = null;
for (int i = 0; i < target.basicBlock.transformationMetadata.Count(); i++) {
// get graph transformer metadata for basic blocks
if ((target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock) == null) {
continue;
}
targetMetadata = (target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock);
break;
}
if (targetMetadata == null) {
throw new ArgumentException("Not able to find metadata for target basic block.");
}
// get the link from the target basic block to the obfuscation graph
BasicBlockGraphNodeLink targetGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in targetMetadata.correspondingGraphNodes) {
if (tempLink.validPathId == currentValidPathId) {
targetGraphLink = tempLink;
break;
}
}
if (targetGraphLink == null) {
throw new ArgumentNullException("Could not find link from target basic block to the graph for the given path id.");
}
// choose randomly to either just correct the pointer position or to inject a "state change"
switch (this.prng.Next(this.stateChangeWeight)) {
// case: "state change"
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// generate code for the "state change"
BasicBlock stateChangeBasicBlock = null;
SwitchBranchTarget stateChangeExitBranch = null;
this.createCodeStateChange(ref stateChangeBasicBlock, ref stateChangeExitBranch, randomStateGenerator, currentGraphLink, intStateLocal);
cfgManipulator.insertBasicBlockBetweenBranch(stateExitBranch, currentValidPathId, stateChangeBasicBlock, stateChangeExitBranch, 0);
// create for each valid path a branch in the switch statement of the "state change"
for (int changedCurrentValidPathId = 0; changedCurrentValidPathId < this.graph.graphValidPathCount; changedCurrentValidPathId++) {
// ignore first valid path (with id 0)
// => add artificial branch to original branch target (for the changed current valid path id)
if (changedCurrentValidPathId != 0) {
// fill switch taken branch list with null when index is out of range
while (stateChangeExitBranch.takenTarget.Count() <= changedCurrentValidPathId) {
stateChangeExitBranch.takenTarget.Add(null);
}
// randomly chose what the target of the current branch should be (weight to use an existing basic block to have less memory consumption)
switch (this.prng.Next(this.duplicateBasicBlockWeight)) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// duplicate the target basic block
BasicBlock duplicatedBasicBlock = this.duplicateBasicBlock(originalMethodCfg, methodCfg, listOfTargets.ElementAt(0).basicBlock);
methodCfg.basicBlocks.Add(duplicatedBasicBlock);
basicBlocksToProcess.Add(duplicatedBasicBlock);
// add new basic block as target of the switch case
stateChangeExitBranch.takenTarget[changedCurrentValidPathId] = duplicatedBasicBlock;
duplicatedBasicBlock.entryBranches.Add(stateChangeExitBranch);
// add new basic block to the list of target basic blocks
target = new Target();
target.basicBlock = duplicatedBasicBlock;
listOfTargets.Add(target);
// add duplicated basic block to the list of possible target basic blocks
possibleTargetBasicBlocks.Add(duplicatedBasicBlock);
// create metadata for the newly created basic block
if (!createAndAddMetadata(duplicatedBasicBlock)) {
throw new ArgumentException("Creating metadata for the duplicated basic block failed.");
}
break;
}
default: {
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock newTarget = possibleTargetBasicBlocks.ElementAt(randPosition);
target = new Target();
target.basicBlock = newTarget;
listOfTargets.Add(target);
// set switch taken branch for current valid path id to the chosen branch target
stateChangeExitBranch.takenTarget[changedCurrentValidPathId] = target.basicBlock;
target.basicBlock.entryBranches.Add(stateChangeExitBranch);
break;
}
}
}
// set current valid path id of the target
target.currentValidPathId = changedCurrentValidPathId;
// get the metadata for the change target basic block
GraphTransformerMetadataBasicBlock changeTargetMetadata = null;
for (int i = 0; i < target.basicBlock.transformationMetadata.Count(); i++) {
// get graph transformer metadata for basic blocks
if ((target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock) == null) {
continue;
}
changeTargetMetadata = (target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock);
break;
}
if (changeTargetMetadata == null) {
throw new ArgumentException("Not able to find metadata for target basic block.");
}
// get the link from the change target basic block to the obfuscation graph
BasicBlockGraphNodeLink changeTargetGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in changeTargetMetadata.correspondingGraphNodes) {
if (tempLink.validPathId == changedCurrentValidPathId) {
changeTargetGraphLink = tempLink;
break;
}
}
if (changeTargetGraphLink == null) {
throw new ArgumentNullException("Could not find link from target basic block to the graph for the given path id.");
}
// correct the pointer position to the obfuscation graph
this.injectLinkMoveCode(cfgManipulator, currentGraphLink, changeTargetGraphLink, stateChangeExitBranch, changedCurrentValidPathId, currentNodeLocal);
// if debugging is activated => dump method cfg and add code to dump current graph
if (this.debugging) {
List<IOperation> debugOperations = new List<IOperation>();
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingNumber.ToString().PadLeft(3, '0') + "_" + target.basicBlock.id.ToString() + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method)));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldloc, currentNodeLocal));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.debuggingDumpGraphMethod));
target.basicBlock.operations.InsertRange(0, debugOperations);
//this.logger.dumpMethodCfg(methodCfg, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method));
this.debuggingNumber++;
}
}
break;
}
// case: correct pointer position
default: {
this.injectLinkMoveCode(cfgManipulator, currentGraphLink, targetGraphLink, stateExitBranch, currentGraphLink.validPathId, currentNodeLocal);
// if debugging is activated => dump method cfg and add code to dump current graph
if (this.debugging) {
List<IOperation> debugOperations = new List<IOperation>();
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingNumber.ToString().PadLeft(3, '0') + "_" + target.basicBlock.id.ToString() + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method)));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldloc, currentNodeLocal));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.debuggingDumpGraphMethod));
target.basicBlock.operations.InsertRange(0, debugOperations);
//this.logger.dumpMethodCfg(methodCfg, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method));
this.debuggingNumber++;
}
break;
}
}
}
// search for all semantically equal basic blocks in the modified method CFG (as possible targets)
searchSementicId = introBranch.notTakenTarget.semanticId;
possibleTargetBasicBlocks = new List<BasicBlock>();
if (searchSementicId != -1) {
foreach (BasicBlock searchBasicBlock in methodCfg.basicBlocks) {
if (searchBasicBlock.semanticId == searchSementicId) {
possibleTargetBasicBlocks.Add(searchBasicBlock);
}
}
if (possibleTargetBasicBlocks.Count() == 0) {
throw new ArgumentException("Not able to find any semantically equal basic block in CFG.");
}
}
else {
possibleTargetBasicBlocks.Add(introBranch.notTakenTarget);
}
// create a list of target basic blocks of this branch
listOfTargets = new List<Target>();
target = new Target();
target.basicBlock = introBranch.notTakenTarget;
listOfTargets.Add(target);
// generate code for the "state switch"
stateBasicBlock = null;
stateExitBranch = null;
this.createCodeStateSwitch(ref stateBasicBlock, ref stateExitBranch, intStateLocal, metadata.correspondingGraphNodes);
cfgManipulator.insertBasicBlockBetweenBranch(introBranch, false, stateBasicBlock, stateExitBranch, 0);
// create for each valid path a branch in the switch statement of the "state switch"
for (currentValidPathId = 0; currentValidPathId < this.graph.graphValidPathCount; currentValidPathId++) {
// ignore first valid path (with id 0)
// => add artificial branch to original branch target (for the current valid path id)
if (currentValidPathId != 0) {
// fill switch taken branch list with null when index is out of range
while (stateExitBranch.takenTarget.Count() <= currentValidPathId) {
stateExitBranch.takenTarget.Add(null);
}
// randomly chose what the target of the current branch should be (weight to use an existing basic block to have less memory consumption)
switch (this.prng.Next(this.duplicateBasicBlockWeight)) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// duplicate the target basic block
BasicBlock duplicatedBasicBlock = this.duplicateBasicBlock(originalMethodCfg, methodCfg, listOfTargets.ElementAt(0).basicBlock);
methodCfg.basicBlocks.Add(duplicatedBasicBlock);
basicBlocksToProcess.Add(duplicatedBasicBlock);
// add new basic block as target of the switch case
stateExitBranch.takenTarget[currentValidPathId] = duplicatedBasicBlock;
duplicatedBasicBlock.entryBranches.Add(stateExitBranch);
// add new basic block to the list of target basic blocks
target = new Target();
target.basicBlock = duplicatedBasicBlock;
listOfTargets.Add(target);
// add duplicated basic block to the list of possible target basic blocks
possibleTargetBasicBlocks.Add(duplicatedBasicBlock);
// create metadata for the newly created basic block
if (!createAndAddMetadata(duplicatedBasicBlock)) {
throw new ArgumentException("Creating metadata for the duplicated basic block failed.");
}
break;
}
default: {
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock newTarget = possibleTargetBasicBlocks.ElementAt(randPosition);
target = new Target();
target.basicBlock = newTarget;
listOfTargets.Add(target);
//set switch taken branch for current valid path id to the chosen branch target
stateExitBranch.takenTarget[currentValidPathId] = target.basicBlock;
target.basicBlock.entryBranches.Add(stateExitBranch);
break;
}
}
}
// set current valid path id of the target
target.currentValidPathId = currentValidPathId;
// get the link from the current basic block to the obfuscation graph
BasicBlockGraphNodeLink currentGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in metadata.correspondingGraphNodes) {
if (tempLink.validPathId == currentValidPathId) {
currentGraphLink = tempLink;
break;
}
}
if (currentGraphLink == null) {
throw new ArgumentNullException("Could not find link from current basic block to the graph for the given path id.");
}
// get the metadata for the target basic block
GraphTransformerMetadataBasicBlock targetMetadata = null;
for (int i = 0; i < target.basicBlock.transformationMetadata.Count(); i++) {
// get graph transformer metadata for basic blocks
if ((target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock) == null) {
continue;
}
targetMetadata = (target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock);
break;
}
if (targetMetadata == null) {
throw new ArgumentException("Not able to find metadata for target basic block.");
}
// get the link from the target basic block to the obfuscation graph
BasicBlockGraphNodeLink targetGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in targetMetadata.correspondingGraphNodes) {
if (tempLink.validPathId == currentValidPathId) {
targetGraphLink = tempLink;
break;
}
}
if (targetGraphLink == null) {
throw new ArgumentNullException("Could not find link from target basic block to the graph for the given path id.");
}
// choose randomly to either just correct the pointer position or to inject a "state change"
switch (this.prng.Next(this.stateChangeWeight)) {
// case: "state change"
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// generate code for the "state change"
BasicBlock stateChangeBasicBlock = null;
SwitchBranchTarget stateChangeExitBranch = null;
this.createCodeStateChange(ref stateChangeBasicBlock, ref stateChangeExitBranch, randomStateGenerator, currentGraphLink, intStateLocal);
cfgManipulator.insertBasicBlockBetweenBranch(stateExitBranch, currentValidPathId, stateChangeBasicBlock, stateChangeExitBranch, 0);
// create for each valid path a branch in the switch statement of the "state change"
for (int changedCurrentValidPathId = 0; changedCurrentValidPathId < this.graph.graphValidPathCount; changedCurrentValidPathId++) {
// ignore first valid path (with id 0)
// => add artificial branch to original branch target (for the changed current valid path id)
if (changedCurrentValidPathId != 0) {
// fill switch taken branch list with null when index is out of range
while (stateChangeExitBranch.takenTarget.Count() <= changedCurrentValidPathId) {
stateChangeExitBranch.takenTarget.Add(null);
}
// randomly chose what the target of the current branch should be (weight to use an existing basic block to have less memory consumption)
switch (this.prng.Next(this.duplicateBasicBlockWeight)) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5: {
// duplicate the target basic block
BasicBlock duplicatedBasicBlock = this.duplicateBasicBlock(originalMethodCfg, methodCfg, listOfTargets.ElementAt(0).basicBlock);
methodCfg.basicBlocks.Add(duplicatedBasicBlock);
basicBlocksToProcess.Add(duplicatedBasicBlock);
// add new basic block as target of the switch case
stateChangeExitBranch.takenTarget[changedCurrentValidPathId] = duplicatedBasicBlock;
duplicatedBasicBlock.entryBranches.Add(stateChangeExitBranch);
// add new basic block to the list of target basic blocks
target = new Target();
target.basicBlock = duplicatedBasicBlock;
listOfTargets.Add(target);
// add duplicated basic block to the list of possible target basic blocks
possibleTargetBasicBlocks.Add(duplicatedBasicBlock);
// create metadata for the newly created basic block
if (!createAndAddMetadata(duplicatedBasicBlock)) {
throw new ArgumentException("Creating metadata for the duplicated basic block failed.");
}
break;
}
default: {
// use a random possible basic block as target
int randPosition = this.prng.Next(possibleTargetBasicBlocks.Count());
BasicBlock newTarget = possibleTargetBasicBlocks.ElementAt(randPosition);
target = new Target();
target.basicBlock = newTarget;
listOfTargets.Add(target);
// set switch taken branch for current valid path id to the chosen branch target
stateChangeExitBranch.takenTarget[changedCurrentValidPathId] = target.basicBlock;
target.basicBlock.entryBranches.Add(stateChangeExitBranch);
break;
}
}
}
// set current valid path id of the target
target.currentValidPathId = changedCurrentValidPathId;
// get the metadata for the change target basic block
GraphTransformerMetadataBasicBlock changeTargetMetadata = null;
for (int i = 0; i < target.basicBlock.transformationMetadata.Count(); i++) {
// get graph transformer metadata for basic blocks
if ((target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock) == null) {
continue;
}
changeTargetMetadata = (target.basicBlock.transformationMetadata.ElementAt(i) as GraphTransformerMetadataBasicBlock);
break;
}
if (changeTargetMetadata == null) {
throw new ArgumentException("Not able to find metadata for target basic block.");
}
// get the link from the change target basic block to the obfuscation graph
BasicBlockGraphNodeLink changeTargetGraphLink = null;
foreach (BasicBlockGraphNodeLink tempLink in changeTargetMetadata.correspondingGraphNodes) {
if (tempLink.validPathId == changedCurrentValidPathId) {
changeTargetGraphLink = tempLink;
break;
}
}
if (changeTargetGraphLink == null) {
throw new ArgumentNullException("Could not find link from target basic block to the graph for the given path id.");
}
// correct the pointer position to the obfuscation graph
this.injectLinkMoveCode(cfgManipulator, currentGraphLink, changeTargetGraphLink, stateChangeExitBranch, changedCurrentValidPathId, currentNodeLocal);
// if debugging is activated => dump method cfg and add code to dump current graph
if (this.debugging) {
List<IOperation> debugOperations = new List<IOperation>();
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingNumber.ToString().PadLeft(3, '0') + "_" + target.basicBlock.id.ToString() + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method)));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldloc, currentNodeLocal));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.debuggingDumpGraphMethod));
target.basicBlock.operations.InsertRange(0, debugOperations);
//this.logger.dumpMethodCfg(methodCfg, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method));
this.debuggingNumber++;
}
}
break;
}
// case: correct pointer position
default: {
this.injectLinkMoveCode(cfgManipulator, currentGraphLink, targetGraphLink, stateExitBranch, currentGraphLink.validPathId, currentNodeLocal);
// if debugging is activated => dump method cfg and add code to dump current graph
if (this.debugging) {
List<IOperation> debugOperations = new List<IOperation>();
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldstr, this.debuggingNumber.ToString().PadLeft(3, '0') + "_" + target.basicBlock.id.ToString() + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method)));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldarg_0));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.interfaceStartPointerGet));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Ldloc, currentNodeLocal));
debugOperations.Add(this.helperClass.createNewOperation(OperationCode.Callvirt, this.debuggingDumpGraphMethod));
target.basicBlock.operations.InsertRange(0, debugOperations);
//this.logger.dumpMethodCfg(methodCfg, this.debuggingNumber.ToString().PadLeft(3, '0') + "_obfu_" + this.logger.makeFuncSigString(methodCfg.method));
this.debuggingNumber++;
}
break;
}
}
}
}
// check if the current exit branch is of type "try block target"
else if (currentBasicBlock.exitBranch as TryBlockTarget != null) {
throw new ArgumentException("Not yet implemented.");
}
// check if the current exit branch is of type "switch branch target"
else if (currentBasicBlock.exitBranch as SwitchBranchTarget != null) {
throw new ArgumentException("Not yet implemented.");
}
// check if the current exit branch is of type "exception branch target"
else if (currentBasicBlock.exitBranch as ExceptionBranchTarget != null) {
throw new ArgumentException("Not yet implemented.");
}
// check if the current exit branch is of type "exit branch target"
else if (currentBasicBlock.exitBranch as ExitBranchTarget != null) {
continue;
}
// check if the current exit branch is of type "throw branch target"
else if (currentBasicBlock.exitBranch as ThrowBranchTarget != null) {
continue;
}
// this case should never be reached
else {
throw new ArgumentException("Do not know how to handle branch.");
}
}
System.Console.WriteLine("Basic Blocks to process (Control Flow): " + basicBlocksToProcess.Count());
// check if basic blocks exist to process => if not break loop
if (basicBlocksToProcess.Count() == 0) {
break;
}
// adjust probability to duplicate basic blocks (each processing round the probability drops to duplicate a basic block)
this.duplicateBasicBlockWeight += this.duplicateBasicBlockCorrectionValue;
// adjust probability to insert a state change (each processing round the probability drops to insert a state change)
this.stateChangeWeight += this.stateChangeCorrectionValue;
}
}
// this function injects an opaque predicate to the target branch
private void injectOpaquePredicateCode(CfgManipulator cfgManipulator, Target target, ref ConditionalBranchTarget opaqueExitBranch, IBranchTarget targetBranch, BasicBlockGraphNodeLink link, int currentValidPathId, int opaquePredicate, LocalDefinition currentNodeLocal) {
// create "true" or "false" opaque predicate and add it to the code
switch (opaquePredicate) {
// "true" opaque predicate
case 0: {
BasicBlock opaqueStartBasicBlock = null;
this.createCodeTruePredicate(ref opaqueStartBasicBlock, ref opaqueExitBranch, link, currentNodeLocal);
// inject target branch with opaque predicate
if ((targetBranch as SwitchBranchTarget) != null) {
SwitchBranchTarget tempTargetBranch = (targetBranch as SwitchBranchTarget);
cfgManipulator.insertBasicBlockBetweenBranch(tempTargetBranch, currentValidPathId, opaqueStartBasicBlock, opaqueExitBranch, true);
}
else {
throw new ArgumentException("Not implemented yet.");
}
// set template semantic id of dead code basic block
BasicBlock deadCodeBasicBlock = opaqueExitBranch.notTakenTarget;
GraphTransformerDeadCodeBasicBlock deadCodeMetadata = (deadCodeBasicBlock.transformationMetadata.ElementAt(0) as GraphTransformerDeadCodeBasicBlock);
deadCodeMetadata.semanticId = target.basicBlock.semanticId;
break;
}
// "false" opaque predicate
case 1: {
BasicBlock opaqueStartBasicBlock = null;
this.createCodeFalsePredicate(ref opaqueStartBasicBlock, ref opaqueExitBranch, link, currentNodeLocal);
// inject target branch with opaque predicate
if ((targetBranch as SwitchBranchTarget) != null) {
SwitchBranchTarget tempTargetBranch = (targetBranch as SwitchBranchTarget);
cfgManipulator.insertBasicBlockBetweenBranch(tempTargetBranch, currentValidPathId, opaqueStartBasicBlock, opaqueExitBranch, false);
}
else {
throw new ArgumentException("Not implemented yet.");
}
// set template semantic id of dead code basic block
BasicBlock deadCodeBasicBlock = opaqueExitBranch.takenTarget;
GraphTransformerDeadCodeBasicBlock deadCodeMetadata = (deadCodeBasicBlock.transformationMetadata.ElementAt(0) as GraphTransformerDeadCodeBasicBlock);
deadCodeMetadata.semanticId = target.basicBlock.semanticId;
break;
}
// "Random" opaque predicate.
case 2: {
BasicBlock opaqueStartBasicBlock = null;
if((targetBranch as SwitchBranchTarget) != null) {
SwitchBranchTarget tempTargetBranch = (targetBranch as SwitchBranchTarget);
var destinationBlock = tempTargetBranch.takenTarget[currentValidPathId];
this.createCodeRandomPredicate(ref opaqueStartBasicBlock, ref opaqueExitBranch, link, currentNodeLocal);
bool chooseBranch = prng.Next(1) == 0;
cfgManipulator.insertBasicBlockBetweenBranch(tempTargetBranch, currentValidPathId, opaqueStartBasicBlock, opaqueExitBranch, chooseBranch);
}
else {
throw new ArgumentException("Not implemented yet.");
}
break;
}
default:
throw new ArgumentException("This case should never be reached.");
}
}
