public override Implementation VisitImplementation(Implementation node)
{
LoopDetector loopDetector = new LoopDetector();
loopDetector.Visit(node);
this.blocksWithinNautralLoops = loopDetector.getBlocksInNaturalLoops();
this.visit_happened = true;
return(base.VisitImplementation(node));
}
private static void InstrumentEnclave(
Program prog,
Implementation impl,
Dictionary <Tuple <string, Cmd, AssertCmd>, bool> storeAddressRegionDB,
Dictionary <Tuple <string, Cmd, AssertCmd>, bool> loadAddressRegionDB)
{
Console.WriteLine("CfiVerifier found " + impl.Blocks.Count + " basic blocks");
(new SpecialInstructionLifter()).Visit(prog);
// (new ConstantExpressionSimplifier()).Visit(prog);
Utils.PrintProg(prog);
if (Options.splitMemoryModel)
{
(new SplitMemoryModeler(storeAddressRegionDB, loadAddressRegionDB, false)).Visit(prog);
(new HavocingLoader()).Visit(prog);
}
Utils.PrintProg(prog);
(new ModularVerificationSetup()).Visit(prog);
Utils.PrintProg(prog);
//(new Utils.DeadCodeEliminator()).Visit(prog); //mostly to remove assingments to useless CPU flags
//if (Utils.verbosityLevel(2)) { Console.WriteLine("InstrumentEnclave: replacing call instructions with CallCmd"); }
// (new Utils.HavocingAdversary()).Visit(impl); //FIXME: this should be enabled.
LoopDetector loopDetector = new LoopDetector();
loopDetector.Visit(impl); //necessary before querying the stack size estimate
List <Block> blocksInNaturalLoops = loopDetector.getBlocksInNaturalLoops();
if (blocksInNaturalLoops.Count > 0)
{
Console.WriteLine("CfiVerifier found one or more loops");
Console.WriteLine("Blocks in loops: {0}", blocksInNaturalLoops.MapConcat(x => x.Label, ","));
}
List <Block> loopHeaders = loopDetector.getLoopHeaders();
if (loopHeaders.Count > 0)
{
Console.WriteLine("LOOP HEADERS: {0}", loopHeaders.MapConcat(x => x.Label, ","));
Tuple <String, List <String> > result = Utils.HandleLoops(prog, impl);
String memCheckpointLabel = result.Item1;
List <String> loopHeaderLabels = result.Item2;
Utils.InstrumentLoopInvariant(prog, impl, memCheckpointLabel, loopHeaderLabels);
}
VCSplitter.LaunchVCSplitter(impl);
(new EnvironmentSetup()).Visit(prog); //TODO move this earlier, maybe before DeadCodeEliminator
(new ProofObligations()).Visit(prog);
Console.WriteLine("\nInstrumented Program with CFI assertions and generated output file {0}", Options.instrumentedFile);
Utils.PrintProg(prog);
VCSplitter.Instance.PrintInstrumentedProcedures(prog);
VCSplitter.Instance.PrintAssertionTypes();
}
public static Tuple <String, List <String> > HandleLoops(Program prog, Implementation impl)
{
LoopDetector loopDetector = new LoopDetector();
loopDetector.Visit(impl); //necessary before querying the stack size estimate
List <Block> blocksInNaturalLoops = loopDetector.getBlocksInNaturalLoops();
List <Block> loopHeaders = loopDetector.getLoopHeaders();
List <String> loopHeaderLabels = new List <string>();
loopHeaders.Iter(l => loopHeaderLabels.Add(l.Label));
//if (loopHeaders.Count > 0) { Console.WriteLine("LOOP HEADERS: {0}", loopHeaders.MapConcat(x => x.Label, ",")); }
var graph = Program.GraphFromImpl(impl);
//Utils.Assert(graph.Reducible, "Irreducible flow graphs are unsupported.");
Utils.Assert(graph.Nodes.Count() > 1, "Doesn't work for graphs with 1 node");
//figure out the source node. that's where the program starts.
IEnumerable <Block> sourceNodes = graph.Nodes.Where(n => graph.Predecessors(n).Count() == 0);
//Also assert that there is only one source node (unless there is unreachable node in the CFG)
Utils.Assert(sourceNodes.Count() == 1);
Block sourceNode = sourceNodes.ElementAt(0);
//Console.WriteLine("SOURCE NODE: {0}", sourceNode.Label);
//traverse starting from source node until you get nondeterministic goto, or a loop header
Block currentNode = sourceNode;
while (graph.Successors(currentNode).Count() < 2)
{
IEnumerable <Block> successors = graph.Successors(currentNode);
//we know this is a loopy program, so we should not get to a sink node in this loop.
Utils.Assert(successors.Count() > 0, "We got to a sink node. why???");
Block nextNode = successors.ElementAt(0);
//encountered a loop header before a CFG split?
if (loopHeaderLabels.Contains(nextNode.Label))
{
break;
}
currentNode = nextNode;
}
//Console.WriteLine("We should capture mem here: {0}", currentNode.Label);
return(new Tuple <string, List <string> >(currentNode.Label, loopHeaderLabels));
}
