// this function fills the rest of the graph with random nodes
private void fillNodesRecursively(NodeObject currentNode, List<int> currentPosition, int currentDepth, int maxDepth, List<PossibleNode> allPossibleNodes, ValidGraphPath[] validPaths) {
// check if the maximal depth is reached
if (currentDepth >= maxDepth) {
return;
}
// fill all missing nodes of the current object with new random nodes
for (int idx = 0; idx < currentNode.dimension; idx++) {
// copy position list and add path index to the position
List<int> tempCurrentPosition = new List<int>(currentPosition);
tempCurrentPosition.Add(idx);
if (currentNode.nodeObjects[idx] == null) {
// get random possible node from list of all possible nodes
int randElement = this.prng.Next(allPossibleNodes.Count);
PossibleNode possibleNode = allPossibleNodes.ElementAt(randElement);
NamespaceTypeDefinition classToUse = possibleNode.givenClass;
MethodDefinition nodeConstructor = possibleNode.nodeConstructor;
// generate path element from chosen interface
PathElement pathElement = new PathElement();
// create new node object
currentNode.nodeObjects[idx] = new NodeObject(this.graphDimension, this.graphValidPathCount, classToUse, nodeConstructor, pathElement, tempCurrentPosition);
// search through every valid path if the new created filler node has the same attributes as the valid path node
// => add it to the list of possible nodes that can be used for an exchange between valid node and filler node
for (int validPathId = 0; validPathId < validPaths.Count(); validPathId++) {
for (int depth = 0; depth < validPaths[validPathId].pathElements.Count(); depth++) {
// check if the used class of the current filler node is in the list of possible classes of the valid path node
if (validPaths[validPathId].pathElements.ElementAt(depth).linkGraphObject.possibleClasses.Contains(classToUse)) {
// add current filler node to the list of possible exchange nodes
if (!validPaths[validPathId].pathElements.ElementAt(depth).linkGraphObject.possibleExchangeObjects.Contains(currentNode.nodeObjects[idx])) {
validPaths[validPathId].pathElements.ElementAt(depth).linkGraphObject.possibleExchangeObjects.Add(currentNode.nodeObjects[idx]);
}
}
}
}
}
this.fillNodesRecursively(currentNode.nodeObjects[idx], tempCurrentPosition, currentDepth + 1, maxDepth, allPossibleNodes, validPaths);
}
}
// dumps the rest of the graph recursively
// IMPORTANT: will crash if a loop exists in the graph
private void dumpGraphRecursively(System.IO.StreamWriter dotFile, NodeObject currentNode, String nodeName, bool dumpOnlyValidPath) {
// write current node to file but only the valid path
if (dumpOnlyValidPath) {
if (currentNode.elementOfValidPath.Count() == 0) {
return;
}
dotFile.WriteLine(nodeName + " [shape=record]");
dotFile.Write(nodeName + " [label=\"{");
dotFile.Write("Node: " + nodeName + "|");
dotFile.Write("Class: " + this.sanitizeString(currentNode.thisClass.ToString()) + "|");
String tempOutput = "";
foreach (PathElement pathElement in currentNode.pathElements) {
tempOutput = "";
foreach (ITypeReference interfaceInList in pathElement.validInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("valid Interfaces (valid ID: " + pathElement.validPathId.ToString() + "): " + tempOutput + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in pathElement.invalidInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("invalid Interfaces (valid ID: " + pathElement.validPathId.ToString() + "): " + tempOutput + "|");
}
dotFile.Write("Constructor: " + this.makeFuncSigString(currentNode.constructorToUse) + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in currentNode.pathElements.ElementAt(0).mandatoryInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("mandatory Interfaces: " + tempOutput + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in currentNode.pathElements.ElementAt(0).forbiddenInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("forbidden Interfaces: " + tempOutput + "|");
tempOutput = "";
foreach (NamespaceTypeDefinition classInList in currentNode.possibleClasses) {
tempOutput += this.sanitizeString(classInList.ToString()) + "; ";
}
dotFile.Write("possible Classes: " + tempOutput + "|");
String positionString = "";
foreach (int position in currentNode.positionInGraph) {
positionString += position.ToString() + ";";
}
dotFile.Write("Position: " + positionString + "|");
positionString = "";
foreach (NodeObject possibleNode in currentNode.possibleExchangeObjects) {
positionString += "(";
foreach (int position in possibleNode.positionInGraph) {
positionString += position.ToString() + ";";
}
positionString += ") ";
}
dotFile.Write("Possible exchange nodes: " + positionString + "|");
String validPathIdString = "";
foreach (int validPathId in currentNode.elementOfValidPath) {
validPathIdString += validPathId.ToString() + ";";
}
dotFile.Write("Valid Path Ids: " + validPathIdString);
dotFile.WriteLine("}\"]");
for (int idx = 0; idx < currentNode.dimension; idx++) {
// check if the tree is a complete tree
if (currentNode.nodeObjects[idx] == null) {
continue;
}
if (currentNode.nodeObjects[idx].elementOfValidPath.Count() != 0) {
dotFile.WriteLine(nodeName + "-> " + nodeName + "_" + idx.ToString() + "[ color=\"green\" ]");
// dump rest of the graph recursively
this.dumpGraphRecursively(dotFile, currentNode.nodeObjects[idx], nodeName + "_" + idx.ToString(), true);
}
}
}
// write current node to file with the whole graph
else {
dotFile.WriteLine(nodeName + " [shape=record]");
dotFile.Write(nodeName + " [label=\"{");
dotFile.Write("Node: " + nodeName + "|");
dotFile.Write("Class: " + this.sanitizeString(currentNode.thisClass.ToString()) + "|");
String tempOutput = "";
foreach (PathElement pathElement in currentNode.pathElements) {
tempOutput = "";
foreach (ITypeReference interfaceInList in pathElement.validInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("valid Interfaces (valid ID: " + pathElement.validPathId.ToString() + "): " + tempOutput + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in pathElement.invalidInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("invalid Interfaces (valid ID: " + pathElement.validPathId.ToString() + "): " + tempOutput + "|");
}
dotFile.Write("Constructor: " + this.makeFuncSigString(currentNode.constructorToUse) + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in currentNode.pathElements.ElementAt(0).mandatoryInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("mandatory Interfaces: " + tempOutput + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in currentNode.pathElements.ElementAt(0).forbiddenInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("forbidden Interfaces: " + tempOutput + "|");
tempOutput = "";
foreach (NamespaceTypeDefinition classInList in currentNode.possibleClasses) {
tempOutput += this.sanitizeString(classInList.ToString()) + "; ";
}
dotFile.Write("possible Classes: " + tempOutput + "|");
String positionString = "";
foreach (int position in currentNode.positionInGraph) {
positionString += position.ToString() + ";";
}
dotFile.Write("Position: " + positionString + "|");
positionString = "";
foreach (NodeObject possibleNode in currentNode.possibleExchangeObjects) {
positionString += "(";
foreach (int position in possibleNode.positionInGraph) {
positionString += position.ToString() + ";";
}
positionString += ") ";
}
dotFile.Write("Possible exchange nodes: " + positionString + "|");
String validPathIdString = "";
foreach (int validPathId in currentNode.elementOfValidPath) {
validPathIdString += validPathId.ToString() + ";";
}
dotFile.Write("Valid Path Ids: " + validPathIdString);
dotFile.WriteLine("}\"]");
for (int idx = 0; idx < currentNode.dimension; idx++) {
// check if the tree is a complete tree
if (currentNode.nodeObjects[idx] == null) {
continue;
}
if (currentNode.nodeObjects[idx].elementOfValidPath.Count() != 0) {
dotFile.WriteLine(nodeName + "-> " + nodeName + "_" + idx.ToString() + "[ color=\"green\" ]");
}
else {
if (!dumpOnlyValidPath) {
dotFile.WriteLine(nodeName + "-> " + nodeName + "_" + idx.ToString() + "[ color=\"red\" ]");
}
}
// dump rest of the graph recursively
this.dumpGraphRecursively(dotFile, currentNode.nodeObjects[idx], nodeName + "_" + idx.ToString(), false);
}
}
}
// dump graph to a .dot file
// IMPORTANT: will crash if a loop exists in the graph
public void dumpGraph(NodeObject startNode, String fileName, bool dumpOnlyValidPath) {
// shorten file name if it is too long
fileName = fileName.Length >= 230 ? fileName.Substring(0, 230) : fileName;
// dump graph
System.IO.StreamWriter dotFile = new System.IO.StreamWriter(this.logPath + "\\graph_" + fileName + ".dot");
// start .dot file graph
dotFile.WriteLine("digraph G {");
// write start node to file but only the valid path
String nodeName = "Node_0";
if (dumpOnlyValidPath) {
if (startNode.elementOfValidPath.Count() != 0) {
dotFile.WriteLine(nodeName + " [shape=record]");
dotFile.Write(nodeName + " [label=\"{");
dotFile.Write("Node: " + nodeName + "|");
dotFile.Write("Class: " + this.sanitizeString(startNode.thisClass.ToString()) + "|");
String tempOutput = "";
foreach(PathElement pathElement in startNode.pathElements) {
tempOutput = "";
foreach (ITypeReference interfaceInList in pathElement.validInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("valid Interfaces (valid ID: " + pathElement.validPathId.ToString() + "): " + tempOutput + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in pathElement.invalidInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("invalid Interfaces (valid ID: " + pathElement.validPathId.ToString() + "): " + tempOutput + "|");
}
dotFile.Write("Constructor: " + this.makeFuncSigString(startNode.constructorToUse) + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in startNode.pathElements.ElementAt(0).mandatoryInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("mandatory Interfaces: " + tempOutput + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in startNode.pathElements.ElementAt(0).forbiddenInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("forbidden Interfaces: " + tempOutput + "|");
tempOutput = "";
foreach (NamespaceTypeDefinition classInList in startNode.possibleClasses) {
tempOutput += this.sanitizeString(classInList.ToString()) + "; ";
}
dotFile.Write("possible Classes: " + tempOutput + "|");
String positionString = "";
foreach (int position in startNode.positionInGraph) {
positionString += position.ToString() + ";";
}
dotFile.Write("Position: " + positionString + "|");
positionString = "";
foreach (NodeObject possibleNode in startNode.possibleExchangeObjects) {
positionString += "(";
foreach (int position in possibleNode.positionInGraph) {
positionString += position.ToString() + ";";
}
positionString += ") ";
}
dotFile.Write("Possible exchange nodes: " + positionString + "|");
String validPathIdString = "";
foreach (int validPathId in startNode.elementOfValidPath) {
validPathIdString += validPathId.ToString() + ";";
}
dotFile.Write("Valid Path Ids: " + validPathIdString);
dotFile.WriteLine("}\"]");
for (int idx = 0; idx < startNode.dimension; idx++) {
// check if the tree is a complete tree
if (startNode.nodeObjects[idx] == null) {
continue;
}
if (startNode.nodeObjects[idx].elementOfValidPath.Count() != 0) {
dotFile.WriteLine(nodeName + "-> " + nodeName + "_" + idx.ToString() + "[ color=\"green\" ]");
// dump rest of the graph recursively
this.dumpGraphRecursively(dotFile, startNode.nodeObjects[idx], nodeName + "_" + idx.ToString(), true);
}
}
}
}
// write start node to file with the whole graph
else {
dotFile.WriteLine(nodeName + " [shape=record]");
dotFile.Write(nodeName + " [label=\"{");
dotFile.Write("Node: " + nodeName + "|");
dotFile.Write("Class: " + this.sanitizeString(startNode.thisClass.ToString()) + "|");
String tempOutput = "";
foreach (PathElement pathElement in startNode.pathElements) {
tempOutput = "";
foreach (ITypeReference interfaceInList in pathElement.validInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("valid Interfaces (valid ID: " + pathElement.validPathId.ToString() + "): " + tempOutput + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in pathElement.invalidInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("invalid Interfaces (valid ID: " + pathElement.validPathId.ToString() + "): " + tempOutput + "|");
}
dotFile.Write("Constructor: " + this.makeFuncSigString(startNode.constructorToUse) + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in startNode.pathElements.ElementAt(0).mandatoryInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("mandatory Interfaces: " + tempOutput + "|");
tempOutput = "";
foreach (ITypeReference interfaceInList in startNode.pathElements.ElementAt(0).forbiddenInterfaces) {
tempOutput += this.sanitizeString(interfaceInList.ToString()) + "; ";
}
dotFile.Write("forbidden Interfaces: " + tempOutput + "|");
tempOutput = "";
foreach (NamespaceTypeDefinition classInList in startNode.possibleClasses) {
tempOutput += this.sanitizeString(classInList.ToString()) + "; ";
}
dotFile.Write("possible Classes: " + tempOutput + "|");
String positionString = "";
foreach (int position in startNode.positionInGraph) {
positionString += position.ToString() + ";";
}
dotFile.Write("Position: " + positionString + "|");
positionString = "";
foreach (NodeObject possibleNode in startNode.possibleExchangeObjects) {
positionString += "(";
foreach (int position in possibleNode.positionInGraph) {
positionString += position.ToString() + ";";
}
positionString += ") ";
}
dotFile.Write("Possible exchange nodes: " + positionString + "|");
String validPathIdString = "";
foreach (int validPathId in startNode.elementOfValidPath) {
validPathIdString += validPathId.ToString() + ";";
}
dotFile.Write("Valid Path Ids: " + validPathIdString);
dotFile.WriteLine("}\"]");
for (int idx = 0; idx < startNode.dimension; idx++) {
// check if the tree is a complete tree
if (startNode.nodeObjects[idx] == null) {
continue;
}
if (startNode.nodeObjects[idx].elementOfValidPath.Count() != 0) {
dotFile.WriteLine(nodeName + "-> " + nodeName + "_" + idx.ToString() + "[ color=\"green\" ]");
}
else {
dotFile.WriteLine(nodeName + "-> " + nodeName + "_" + idx.ToString() + "[ color=\"red\" ]");
}
// dump rest of the graph recursively
this.dumpGraphRecursively(dotFile, startNode.nodeObjects[idx], nodeName + "_" + idx.ToString(), false);
}
}
// finish graph
dotFile.WriteLine("}");
dotFile.Close();
}
// builds a graph
public void buildGraph(ValidGraphPath[] validPaths) {
// check if at least one valid path is given
int countValidPath = validPaths.Count();
if (countValidPath < 1) {
throw new ArgumentException("At least 1 valid path have to be given.");
}
// check if the path has enough elements
int maxDepth = this.graphDepth;
if (maxDepth <= 1) {
throw new ArgumentException("Path has to have at least 2 elements.");
}
// set needed attributes
this.graphValidPathCount = countValidPath;
// a list of all possible nodes for all graph elements
List<PossibleNode> allPossibleNodes = new List<PossibleNode>();
// get a list of possible nodes that implement the first valid interface of the first node of the first valid path
ITypeReference tempInterface = validPaths[0].pathElements[0].mandatoryInterfaces.ElementAt(0);
List<PossibleNode> possibleNodes = new List<PossibleNode>((List<PossibleNode>)this.graphInterfaces[tempInterface]);
List<PossibleNode> copiedList = new List<PossibleNode>(possibleNodes);
foreach (PossibleNode possibleNode in copiedList) {
// check if all needed interfaces (by all valid paths) are contained by the possible node
// if not => remove if from the list of possible nodes
bool validNode = true;
foreach (ITypeReference neededInterface in validPaths[0].pathElements[0].mandatoryInterfaces) {
if(!possibleNode.givenClass.Interfaces.Contains(neededInterface)) {
validNode = false;
break;
}
}
if(!validNode) {
possibleNodes.Remove(possibleNode);
}
// check if all forbidden interfaces (by all valid paths) are NOT contained by the possible node
// if the possible node contains it => remove it from the list of possible nodes
foreach (ITypeReference forbiddenInterface in validPaths[0].pathElements[0].forbiddenInterfaces) {
if(possibleNode.givenClass.Interfaces.Contains(forbiddenInterface)) {
validNode = false;
break;
}
}
if(!validNode) {
possibleNodes.Remove(possibleNode);
}
}
if (possibleNodes.Count() == 0) {
throw new ArgumentException("No class was found which satisfies the given requirements.");
}
// add all possible nodes for this graph element to the list of all possible nodes
allPossibleNodes.AddRange(possibleNodes);
// get first random node of graph
int randElement = this.prng.Next(possibleNodes.Count());
NamespaceTypeDefinition classToUse = possibleNodes.ElementAt(randElement).givenClass;
MethodDefinition nodeConstructor = possibleNodes.ElementAt(randElement).nodeConstructor;
// create start node of graph
List<int> startPosition = new List<int>();
NodeObject startNode = new NodeObject(this.graphDimension, this.graphValidPathCount, classToUse, nodeConstructor, validPaths[0].pathElements[0], startPosition, 0);
validPaths[0].pathElements[0].linkGraphObject = startNode;
for (int validPathId = 1; validPathId < countValidPath; validPathId++) {
startNode.elementOfValidPath.Add(validPathId);
startNode.pathElements.Add(validPaths[validPathId].pathElements[0]);
validPaths[validPathId].pathElements[0].linkGraphObject = startNode;
}
// add possible nodes to list of possible classes
foreach (PossibleNode possibleNode in possibleNodes) {
startNode.possibleClasses.Add(possibleNode.givenClass);
}
// build all valid paths
for (int validPathId = 0; validPathId < countValidPath; validPathId++) {
NodeObject currentNode = startNode;
List<int> positionInGraph = new List<int>();
// build a random valid path
for (int idx = 1; idx < maxDepth; idx++) {
// get a list of possible nodes that implement the first valid interface of the first node of the first valid path
tempInterface = validPaths[validPathId].pathElements[idx].mandatoryInterfaces.ElementAt(0);
possibleNodes = new List<PossibleNode>((List<PossibleNode>)this.graphInterfaces[tempInterface]);
// sort out nodes that do not satisfy all valid and invalid interface requirements of the node
copiedList = new List<PossibleNode>(possibleNodes);
foreach (PossibleNode possibleNode in copiedList) {
// check if all needed interfaces (by all valid paths) are contained by the possible node
// if not => remove if from the list of possible nodes
bool validNode = true;
foreach (ITypeReference neededInterface in validPaths[validPathId].pathElements[idx].mandatoryInterfaces) {
if (!possibleNode.givenClass.Interfaces.Contains(neededInterface)) {
validNode = false;
break;
}
}
if (!validNode) {
possibleNodes.Remove(possibleNode);
}
// check if all forbidden interfaces (by all valid paths) are NOT contained by the possible node
// if the possible node contains it => remove it from the list of possible nodes
foreach (ITypeReference forbiddenInterface in validPaths[validPathId].pathElements[idx].forbiddenInterfaces) {
if (possibleNode.givenClass.Interfaces.Contains(forbiddenInterface)) {
validNode = false;
break;
}
}
if (!validNode) {
possibleNodes.Remove(possibleNode);
}
}
if (possibleNodes.Count() == 0) {
throw new ArgumentException("No class was found which satisfies the given requirements.");
}
// add all distinct possible nodes for this graph element to the list of all possible nodes
foreach (PossibleNode possibleNode in possibleNodes) {
if (!allPossibleNodes.Contains(possibleNode)) {
allPossibleNodes.Add(possibleNode);
}
}
int pathIdx = validPaths[validPathId].pathIndices[idx];
if (currentNode.nodeObjects[pathIdx] != null) {
// check if the used class of the node satisfy both paths
NamespaceTypeDefinition usedClass = currentNode.nodeObjects[pathIdx].thisClass;
bool validNode = false;
foreach (PossibleNode possibleNode in possibleNodes) {
if (usedClass == possibleNode.givenClass) {
validNode = true;
break;
}
}
if (!validNode) {
throw new ArgumentException("Node does not satisfy both valid paths.");
}
currentNode.nodeObjects[pathIdx].pathElements.Add(validPaths[validPathId].pathElements[idx]);
currentNode.nodeObjects[pathIdx].elementOfValidPath.Add(validPathId);
positionInGraph.Add(pathIdx);
validPaths[validPathId].pathElements[idx].linkGraphObject = currentNode.nodeObjects[pathIdx];
}
else {
// add path index to the position and copy position list
positionInGraph.Add(pathIdx);
List<int> tempPositionInGraph = new List<int>(positionInGraph);
// get random node for graph
randElement = this.prng.Next(possibleNodes.Count());
classToUse = possibleNodes.ElementAt(randElement).givenClass;
nodeConstructor = possibleNodes.ElementAt(randElement).nodeConstructor;
currentNode.nodeObjects[pathIdx] = new NodeObject(this.graphDimension, this.graphValidPathCount, classToUse, nodeConstructor, validPaths[validPathId].pathElements[idx], tempPositionInGraph, validPathId);
validPaths[validPathId].pathElements[idx].linkGraphObject = currentNode.nodeObjects[pathIdx];
// add possible nodes to list of possible classes
foreach (PossibleNode possibleNode in possibleNodes) {
currentNode.nodeObjects[pathIdx].possibleClasses.Add(possibleNode.givenClass);
}
}
currentNode = currentNode.nodeObjects[pathIdx];
}
}
// fill the rest of the graph
this.fillNodesRecursively(startNode, startPosition, 1, maxDepth, allPossibleNodes, validPaths);
this.startingNode = startNode;
}
// this functions creates metadata for the given basic block and adds it
private bool createAndAddMetadata(BasicBlock currentBasicBlock) {
// get metadata of entry basic block (if exists)
IGraphTransformerMetadata previousMetadata = null;
BasicBlock previousBasicBlock = null;
IBranchTarget previousExitBranch = null;
for (int i = 0; i < currentBasicBlock.entryBranches.Count(); i++) {
previousBasicBlock = currentBasicBlock.entryBranches.ElementAt(i).sourceBasicBlock;
for (int j = 0; j < previousBasicBlock.transformationMetadata.Count(); j++) {
// get graph transformer metadata for basic blocks
if ((previousBasicBlock.transformationMetadata.ElementAt(j) as IGraphTransformerMetadata) == null) {
continue;
}
previousMetadata = (previousBasicBlock.transformationMetadata.ElementAt(j) as IGraphTransformerMetadata);
previousExitBranch = currentBasicBlock.entryBranches.ElementAt(i);
break;
}
if (previousMetadata != null) {
break;
}
}
// skip basic block if there is no metadata in one of the entry basic blocks
if (previousMetadata == null) { // TODO: here is room for optimization => do not skip it
return false;
}
List<BasicBlockGraphNodeLink> previousLinks = previousMetadata.correspondingGraphNodes;
// choose the next nodes of the obfuscation graph for the current basic block
NodeObject[] currentNodes = new NodeObject[this.graph.graphValidPathCount];
// check if previous basic block has links to the obfuscation graph for all existing valid paths
// (if previous basic block for example was a "state change" basic block it can only have one link to the obfuscation graph)
// => just copy obfuscation graph nodes of previous basic block if it contains all valid paths
if (previousLinks.Count() == this.graph.graphValidPathCount) {
for (int currentValidPathId = 0; currentValidPathId < this.graph.graphValidPathCount; currentValidPathId++) {
bool found = false;
for (int i = 0; i < previousLinks.Count(); i++) {
if (previousLinks.ElementAt(i).validPathId == currentValidPathId) {
currentNodes[currentValidPathId] = previousLinks.ElementAt(i).graphNode;
found = true;
break;
}
}
if (!found) {
throw new ArgumentException("Was not able to find link to obfuscation graph in previous basic block for at least one valid path.");
}
}
}
// previous basic block does not contain all valid paths
// => copy all existing valid paths links and choose random links for the missing ones
else {
for (int currentValidPathId = 0; currentValidPathId < this.graph.graphValidPathCount; currentValidPathId++) {
bool found = false;
for (int i = 0; i < previousLinks.Count(); i++) {
if (previousLinks.ElementAt(i).validPathId == currentValidPathId) {
currentNodes[currentValidPathId] = previousLinks.ElementAt(i).graphNode;
found = true;
break;
}
}
// if a link for the current valid path does not exist
// => choose randomly a node in the obfuscation graph on the current valid path
if (!found) {
int moveCount = this.prng.Next(this.graphDepth);
NodeObject nextNode = this.graph.startingNode;
for (int move = 0; move < moveCount; move++) {
for (int i = 0; i < nextNode.nodeObjects.Count(); i++) {
// if the child node does not belong to a valid path
// => skip it
if (nextNode.nodeObjects[i].elementOfValidPath.Count() == 0) {
continue;
}
// the child node belongs to a valid path
// => check if it is the correct valid path
else {
// if the child node belongs to the correct valid path
// => set next node to it
if (nextNode.nodeObjects[i].elementOfValidPath.Contains(currentValidPathId)) {
nextNode = nextNode.nodeObjects[i];
break;
}
}
}
if (nextNode == null) {
throw new ArgumentException("Not able to find correct child node.");
}
}
currentNodes[currentValidPathId] = nextNode;
}
}
}
NodeObject[] nextNodes = new NodeObject[this.graph.graphValidPathCount];
for (int currentValidPathId = 0; currentValidPathId < currentNodes.Count(); currentValidPathId++) {
// choose randomly if the pointer of the current valid path should be moved forward
// => move the pointer of the current valid path forward
if (this.prng.Next(2) == 0) {
// get the next node of the valid path
NodeObject nextNode = null;
int nextNodeIdx = 0;
this.getNextNode(ref nextNode, ref nextNodeIdx, currentNodes, currentValidPathId);
nextNodes[currentValidPathId] = nextNode;
}
// => do not move the pointer of the current valid path forward
else {
// set next node in the graph to the current one (it was not changed)
nextNodes[currentValidPathId] = currentNodes[currentValidPathId];
}
}
// create transformation metadata for the current basic block
GraphTransformerMetadataBasicBlock metadata = new GraphTransformerMetadataBasicBlock();
for (int currentValidPathId = 0; currentValidPathId < this.graph.graphValidPathCount; currentValidPathId++) {
BasicBlockGraphNodeLink link = new BasicBlockGraphNodeLink(nextNodes[currentValidPathId], currentValidPathId);
metadata.correspondingGraphNodes.Add(link);
}
currentBasicBlock.transformationMetadata.Add(metadata);
return true;
}
// this function searches for the next node of the given valid path id and the node idx for this node
private void getNextNode(ref NodeObject nextNode, ref int nextNodeIdx, NodeObject[] currentNodes, int currentValidPathId) {
// check if a child node exists
// => if not set next node to starting node
if (currentNodes[currentValidPathId].nodeObjects[0] == null) {
nextNode = this.graph.startingNode;
nextNodeIdx = this.prng.Next(this.graphDimension);
}
else {
for (int i = 0; i < currentNodes[currentValidPathId].nodeObjects.Count(); i++) {
// if the child node does not belong to a valid path
// => skip it
if (currentNodes[currentValidPathId].nodeObjects[i].elementOfValidPath.Count() == 0) {
continue;
}
// the child node belongs to a valid path
// => check if it is the correct valid path
else {
// if the child node belongs to the correct valid path
// => set next node to it
if (currentNodes[currentValidPathId].nodeObjects[i].elementOfValidPath.Contains(currentValidPathId)) {
nextNode = currentNodes[currentValidPathId].nodeObjects[i];
nextNodeIdx = i;
break;
}
}
}
if (nextNode == null) {
throw new ArgumentException("Not able to find correct child node.");
}
}
}
// this function generates and injects code into the given entry branch that moves the pointer from the source node to the target node
private void injectMovePointerCode(CfgManipulator cfgManipulator, NodeObject sourceNode, BasicBlockGraphNodeLink targetLink, IBranchTarget entryBranch, LocalDefinition currentNodeLocal) {
NodeObject targetNode = targetLink.graphNode;
NodeObject currentNode = sourceNode;
UnconditionalBranchTarget branchToManipulate = null;
if ((entryBranch as UnconditionalBranchTarget) != null) {
branchToManipulate = (entryBranch as UnconditionalBranchTarget);
}
else {
throw new ArgumentException("Not yet implemented."); // TODO at the moment we assume unconditional branches as entry
}
// do nothing if the source node is already the same as the target node
if (sourceNode == targetNode) {
return;
}
// check if the pointer have to be moved to the start pointer before it can be moved to the target element
bool goToStart = false;
if (sourceNode.positionInGraph.Count() >= targetNode.positionInGraph.Count()) {
goToStart = true;
}
else {
for (int idx = 0; idx < sourceNode.positionInGraph.Count(); idx++) {
if (sourceNode.positionInGraph.ElementAt(idx) != targetNode.positionInGraph.ElementAt(idx)) {
goToStart = true;
break;
}
}
}
// check how to move the pointer to the target element
// => first go to the start pointer
if (goToStart) {
// generate and inject code that moves the pointer on a random path forward until the start node of the graph is reached
while (currentNode != this.graph.startingNode) {
// generate code to move the pointer to the next node in the graph and inject it
int nextNodeIdx = this.prng.Next(this.graphDimension);
UnconditionalBranchTarget injectedExitBranch = new UnconditionalBranchTarget();
BasicBlock injectedBasicBlock = this.createCodeNextNode(injectedExitBranch, targetLink, currentNodeLocal, nextNodeIdx, true);
cfgManipulator.insertBasicBlockBetweenBranch(branchToManipulate, injectedBasicBlock, injectedExitBranch);
// set the next branch to manipulate as the newly created exit branch
branchToManipulate = injectedExitBranch;
// move pointer to the next node in the graph or to the start node if it does not exist
if (currentNode.nodeObjects[nextNodeIdx] == null) {
currentNode = this.graph.startingNode;
}
else {
currentNode = currentNode.nodeObjects[nextNodeIdx];
}
}
// generate and inject code that moves the pointer to the correct position of the given graph node
foreach (int nextNodeIdx in targetNode.positionInGraph) {
// generate code to move the pointer to the next node in the graph and inject it
UnconditionalBranchTarget injectedExitBranch = new UnconditionalBranchTarget();
BasicBlock injectedBasicBlock = this.createCodeNextNode(injectedExitBranch, targetLink, currentNodeLocal, nextNodeIdx, true);
cfgManipulator.insertBasicBlockBetweenBranch(branchToManipulate, injectedBasicBlock, injectedExitBranch);
// set the next branch to manipulate as the newly created exit branch
branchToManipulate = injectedExitBranch;
// move pointer to the next node in the graph or to the start node if it does not exist
if (currentNode.nodeObjects[nextNodeIdx] == null) {
currentNode = this.graph.startingNode;
}
else {
currentNode = currentNode.nodeObjects[nextNodeIdx];
}
}
}
// => go on a direct path to the target element
else {
// generate and inject code that moves the pointer to the correct position of the given graph node
for (int idx = sourceNode.positionInGraph.Count(); idx < targetNode.positionInGraph.Count(); idx++) {
// generate code to move the pointer to the next node in the graph and inject it
UnconditionalBranchTarget injectedExitBranch = new UnconditionalBranchTarget();
BasicBlock injectedBasicBlock = this.createCodeNextNode(injectedExitBranch, targetLink, currentNodeLocal, targetNode.positionInGraph.ElementAt(idx), true);
cfgManipulator.insertBasicBlockBetweenBranch(branchToManipulate, injectedBasicBlock, injectedExitBranch);
// set the next branch to manipulate as the newly created exit branch
branchToManipulate = injectedExitBranch;
// move pointer to the next node in the graph or to the start node if it does not exist
if (currentNode.nodeObjects[targetNode.positionInGraph.ElementAt(idx)] == null) {
currentNode = this.graph.startingNode;
}
else {
currentNode = currentNode.nodeObjects[targetNode.positionInGraph.ElementAt(idx)];
}
}
}
// check if the final reached node is the same as the target node
if (currentNode != targetNode) {
throw new ArgumentException("Current node and target node are not the same.");
}
}
// this function adds recursively methods that adds the left and the right node to the current node in the graph
// (and calls the next method that adds the left and right node)
private MethodDefinition addNodeRecursively(NodeObject currentNode, int currentDepth, String newMethodName) {
// create first parameter that is the current node in the graph
List<IParameterDefinition> parameters = new List<IParameterDefinition>();
ParameterDefinition parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = this.nodeInterface;
parameters.Add(parameter);
// create second parameter that is the current depth in the graph
parameter = new ParameterDefinition();
parameter.IsIn = false;
parameter.IsOptional = false;
parameter.IsOut = false;
parameter.Type = host.PlatformType.SystemInt32;
parameters.Add(parameter);
// create method to add left and right node to the graph
MethodDefinition newAddNodeMethod = this.helperClass.createNewMethod(newMethodName, this.targetClass, host.PlatformType.SystemVoid, TypeMemberVisibility.Public, parameters, CallingConvention.HasThis, false, false, true); // TODO: method name
// create body of method
ILGenerator ilGenerator = new ILGenerator(this.host, newAddNodeMethod);
// check if max depth of tree is reached
ilGenerator.Emit(OperationCode.Ldarg_2);
ilGenerator.Emit(OperationCode.Ldc_I4, this.graph.graphDepth);
ilGenerator.Emit(OperationCode.Ceq);
ilGenerator.Emit(OperationCode.Ldc_I4_0);
ilGenerator.Emit(OperationCode.Ceq);
ILGeneratorLabel depthReachedBranch = new ILGeneratorLabel();
ilGenerator.Emit(OperationCode.Brfalse, depthReachedBranch);
// set child nodes of this node
MethodDefinition constructorToUse;
for (int i = 0; i < this.graphDimension; i++) {
// get constructor of the child node element
constructorToUse = null;
// check if the child node exists in the graph and the max depth is not yet reached
if (currentNode.nodeObjects[i] == null
&& currentDepth != this.graph.graphDepth) {
throw new ArgumentException("Given depth of graph is larger than the actual graph.");
}
else {
// check if the child node does not exist
// => use a random constructor node
if (currentNode.nodeObjects[i] == null) {
constructorToUse = currentNode.constructorToUse; // TODO: use random node constructor here
}
// else use constructor of given graph node
else {
constructorToUse = currentNode.nodeObjects[i].constructorToUse;
}
}
// set child node
ilGenerator.Emit(OperationCode.Ldarg_1); // current node from which the function is called
ilGenerator.Emit(OperationCode.Ldarg_0); // needed as argument for the constructor
ilGenerator.Emit(OperationCode.Newobj, constructorToUse); // iNode parameter
ilGenerator.Emit(OperationCode.Ldc_I4, i); // index parameter
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
// get child node and set it recursively
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Ldarg_1); // current node from which the function is called
ilGenerator.Emit(OperationCode.Ldc_I4, i); // index parameter
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesGet);
ilGenerator.Emit(OperationCode.Ldarg_2); // arg2 (current depth) + 1
ilGenerator.Emit(OperationCode.Ldc_I4_1);
ilGenerator.Emit(OperationCode.Add);
MethodDefinition newMethodToCall = null;
if (currentDepth == this.graph.graphDepth) {
newMethodToCall = newAddNodeMethod; // TODO: call random node generation method here
}
else {
newMethodToCall = this.addNodeRecursively(currentNode.nodeObjects[i], currentDepth + 1, newMethodName + "_" + i.ToString()); // TODO: method name
}
ilGenerator.Emit(OperationCode.Callvirt, newMethodToCall);
}
ilGenerator.Emit(OperationCode.Ret);
// set child nodes of this node to null
ilGenerator.MarkLabel(depthReachedBranch);
for (int i = 0; i < this.graphDimension; i++) {
ilGenerator.Emit(OperationCode.Ldarg_1);
ilGenerator.Emit(OperationCode.Ldarg_0);
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceStartPointerGet); // iNode parameter
ilGenerator.Emit(OperationCode.Ldc_I4, i); // index parameter
ilGenerator.Emit(OperationCode.Callvirt, this.interfaceChildNodesSet);
}
ilGenerator.Emit(OperationCode.Ret);
// generate body
IMethodBody body = new ILGeneratorMethodBody(ilGenerator, true, 8, newAddNodeMethod, Enumerable<ILocalDefinition>.Empty, Enumerable<ITypeDefinition>.Empty);
newAddNodeMethod.Body = body;
return newAddNodeMethod;
}
public BasicBlockGraphNodeLink(NodeObject graphNode, int validPathId) {
this.validPathId = validPathId;
this.graphNode = graphNode;
}
