/// <summary>
/// Create namespace-pod mapping
/// hash of namespace as key, 'bitvector' of pods as value.
/// </summary>
/// <param name="pods">all pods.</param>
/// <returns>namespace-pod mapping.</returns>
public static Zen <IDictionary <int, IList <bool> > > CreateNSMatrix(Zen <Pod>[] pods)
{
var n = pods.Length;
// create original data.
Dictionary <int, bool[]> originalData = new Dictionary <int, bool[]>();
for (int i = 0; i < n; ++i)
{
var ns = pods[i].GetNS();
var hash = ns.GetHashCode();
if (!originalData.ContainsKey(hash))
{
originalData[hash] = new bool[n];
}
originalData[hash][i] = true;
}
// create zen data.
Zen <IDictionary <int, IList <bool> > > nsMap = Language.EmptyDict <int, IList <bool> >();
foreach (var kv in originalData)
{
nsMap = nsMap.Add(kv.Key, kv.Value);
}
return(nsMap);
}
private static T Interpret <T>(Zen <T> expression, ImmutableDictionary <string, object> arguments)
{
var environment = new ExpressionEvaluatorEnvironment(arguments);
var interpreter = new ExpressionEvaluator();
return((T)expression.Accept(interpreter, environment));
}
/// <summary>
/// Create user-pod mapping
/// hash of user as key, 'bitvector' of pods as value
/// assuming all pods have the user label.
/// </summary>
/// <param name="pods">all pods.</param>
/// <param name="userKey">key of 'user label'.</param>
/// <returns>user-pod mapping.</returns>
public static Zen <IDictionary <int, IList <bool> > > GetUserHash(Zen <Pod>[] pods, Zen <string> userKey)
{
var n = pods.Length;
Dictionary <int, bool[]> originalData = new Dictionary <int, bool[]>();
for (int i = 0; i < n; ++i)
{
var labelValue = pods[i].LabelValue(userKey);
if (labelValue == null)
{
continue;
}
var hash = labelValue.GetHashCode();
if (!originalData.ContainsKey(hash))
{
originalData[hash] = new bool[n];
}
originalData[hash][i] = true;
}
// create zen data.
Zen <IDictionary <int, IList <bool> > > userHashMap = EmptyDict <int, IList <bool> >();
foreach (var kv in originalData)
{
userHashMap = userHashMap.Add(kv.Key, kv.Value);
}
return(userHashMap);
}
public void ReachabilityMatrix_OneDirectionOnly()
{
Zen <Pod>[] pods = new Zen <Pod>[]
{
Pod.Create("default", EmptyDict <string, string>().Add("k0", "v0"), EmptyList <string>().AddBack("k0")),
Pod.Create("ns1", EmptyDict <string, string>().Add("k1", "v1"), EmptyList <string>().AddBack("k1")),
};
Zen <Namespace>[] namespaces = new Zen <Namespace>[]
{
Namespace.Create("default", EmptyDict <string, string>().Add("k0", "v0"), EmptyList <string>().AddBack("k0")),
Namespace.Create("ns1", EmptyDict <string, string>().Add("k1", "v1"), EmptyList <string>().AddBack("k1"))
};
Zen <Policy>[] policies = new Zen <Policy>[]
{
// only one side allows ingress traffic
Policy.Create("default", EmptyDict <string, string>().Add("k0", "v0"),
EmptyDict <string, string>(), EmptyDict <string, string>().Add("k1", "v1"),
EmptyList <string>().AddBack("k0"), EmptyList <string>(), EmptyList <string>().AddBack("k1")),
Policy.Create("ns1", EmptyDict <string, string>().Add("k1", "v1"),
EmptyDict <string, string>(), EmptyDict <string, string>().Add("k1", "v1"),
EmptyList <string>().AddBack("k1"), EmptyList <string>(), EmptyList <string>().AddBack("k1"),
False(), False()),
};
var output = Algorithms.CreateReachMatrix(pods, policies, namespaces).ingressMatrix;
var r0 = EmptyList <bool>().AddBack(true).AddBack(false);
var r1 = EmptyList <bool>().AddBack(false).AddBack(true);
TestHelper.AssertMatrixEqual(output, new Zen <IList <bool> >[] { r0, r1 }, "Reachability Matrix, one direction only");
}
public Zen <bool> Build_Network(Zen <IList <int> > costs)
{
Zen <bool> network_expr = True();
foreach (KeyValuePair <int, HashSet <int> > kvp in node2neighbors)
{
// costs.At(1).Value() == Min(costs.At(0).Value() + 1, costs.At(2).Value() + 1),
Zen <ushort> i = (Zen <ushort>)kvp.Key;
// this is just i, but it doesn't allow me to cast -_-
if (kvp.Key == dst_node)
{
continue;
}
Console.Write(kvp.Key + ": [");
Zen <bool> lower_limit_expr = True();
foreach (Zen <ushort> j in kvp.Value)
{
Console.Write(j + ", ");
lower_limit_expr = And(lower_limit_expr, costs.At(i).Value() <= costs.At(j).Value() + 1);
}
Zen <bool> upper_limit_expr = False();
foreach (Zen <ushort> j in kvp.Value)
{
upper_limit_expr = Or(upper_limit_expr, costs.At(i).Value() >= costs.At(j).Value() + 1);
}
Console.WriteLine("]");
network_expr = And(network_expr, And(lower_limit_expr, upper_limit_expr));
}
Console.WriteLine("physical edges" + physicalEdges.Count);
Console.WriteLine("Network Expression " + network_expr);
return(network_expr);
}
public void SystemIsolationCheckTest()
{
var matrix = new Zen <IList <bool> >[]
{
EmptyList <bool>().AddBack(true).AddBack(true).AddBack(false).AddBack(false).AddBack(false),
EmptyList <bool>().AddBack(false).AddBack(true).AddBack(true).AddBack(false).AddBack(false),
EmptyList <bool>().AddBack(true).AddBack(false).AddBack(true).AddBack(false).AddBack(true),
EmptyList <bool>().AddBack(false).AddBack(false).AddBack(false).AddBack(true).AddBack(false),
EmptyList <bool>().AddBack(true).AddBack(true).AddBack(true).AddBack(true).AddBack(true),
};
var expecteds = new Zen <IList <ushort> >[]
{
EmptyList <ushort>().AddBack(2).AddBack(3).AddBack(4),
EmptyList <ushort>().AddBack(0).AddBack(3).AddBack(4),
EmptyList <ushort>().AddBack(1).AddBack(3),
EmptyList <ushort>().AddBack(0).AddBack(1).AddBack(2).AddBack(4),
EmptyList <ushort>(),
};
for (int i = 0; i < 5; ++i)
{
var output = Verifier.SystemIsolationCheck(matrix, (ushort)i);
Assert.IsTrue(output.ToString().Equals(expecteds[i].ToString()), "SystemIsolatedCheckTest: pod{0} has wrong result.\nExpected: {1}\nGot: {2}", i, expecteds[i].ToString(), output.ToString());
}
}
public static Zen <SimplePacket> Create(
Zen <Ip> dstIp, Zen <Ip> srcIp)
{
return(Language.Create <SimplePacket>(
("DstIp", dstIp),
("SrcIp", srcIp)));
}
public Zen <bool> Matches(Zen <IpHeader> hdr)
{
Zen <bool> dstLowMatch = hdr.GetDstIp().GetValue() >= this.DstIpLow.Value;
Zen <bool> dstHighMatch = hdr.GetDstIp().GetValue() <= this.DstIpHigh.Value;
return(And(dstLowMatch, dstHighMatch));
}
/// <summary>
/// Model check an expression to find inputs that lead to it being false.
/// </summary>
/// <param name="expression">The expression.</param>
/// <returns>
/// Assignment to zen arbitrary variables that make the expression false.
/// Null if no such assignment exists.
/// </returns>
public Dictionary <object, object> ModelCheck(Zen <bool> expression)
{
var symbolicEvaluator = new SymbolicEvaluationVisitor <TModel, TVar, TBool, TInt>(solver);
var env = new SymbolicEvaluationEnvironment <TModel, TVar, TBool, TInt>();
var symbolicResult =
(SymbolicBool <TModel, TVar, TBool, TInt>)expression.Accept(symbolicEvaluator, env);
// Console.WriteLine($"[time] model checking: {watch.ElapsedMilliseconds}ms");
// watch.Restart();
var possibleModel = solver.Satisfiable(symbolicResult.Value);
// Console.WriteLine($"[time] get sat: {watch.ElapsedMilliseconds}ms");
if (!possibleModel.HasValue)
{
return(null);
}
var model = possibleModel.Value;
// compute the input given the assignment
var arbitraryAssignment = new Dictionary <object, object>();
foreach (var kv in symbolicEvaluator.ArbitraryVariables)
{
var expr = kv.Key;
var variable = kv.Value;
arbitraryAssignment.Add(expr, this.solver.Get(model, variable));
}
return(arbitraryAssignment);
}
/// <summary>
/// Processes an event and updates the current state.
/// </summary>
/// <param name="e">The event to process.</param>
/// <param name="currentState">The current watchdog state.</param>
/// <returns>The new watchdog state.</returns>
private static Zen <SwitchState> ProcessEvent(Zen <Event> e, Zen <SwitchState> currentState)
{
var switchState = currentState;
var burstEvent = Event.EventTypeAsByte(EventType.PacketBurstEvent);
var stormStartEvent = Event.EventTypeAsByte(EventType.PfcStormStartEvent);
var stormEndEvent = Event.EventTypeAsByte(EventType.PfcStormEndEvent);
// update the watchdog state based on detection
var conservativeDetectionTime = (ushort)(2 * detectionInterval);
var conservativeRestorationTime = (ushort)(2 * restorationInterval);
var isDetectionEvent1 = And(
switchState.GetStormStartedTime1() > switchState.GetStormEndedTime1(),
e.GetTimeStamp() - switchState.GetStormStartedTime1() >= conservativeDetectionTime);
var isDetectionEvent2 = And(
switchState.GetStormStartedTime2() > switchState.GetStormEndedTime2(),
e.GetTimeStamp() - switchState.GetStormStartedTime2() >= conservativeDetectionTime);
var isRestorationEvent1 = And(
switchState.GetStormEndedTime1() > switchState.GetStormStartedTime1(),
e.GetTimeStamp() - switchState.GetWatchdogStartDropTime1() >= conservativeRestorationTime);
var isRestorationEvent2 = And(
switchState.GetStormEndedTime2() > switchState.GetStormStartedTime2(),
e.GetTimeStamp() - switchState.GetWatchdogStartDropTime2() >= conservativeRestorationTime);
switchState = If(isRestorationEvent1, switchState.SetWatchdogDropPackets1(false), switchState);
switchState = If(isRestorationEvent2, switchState.SetWatchdogDropPackets2(false), switchState);
switchState = If(isDetectionEvent1, switchState.SetWatchdogStartDropTime1(e.GetTimeStamp()).SetWatchdogDropPackets1(true), switchState);
switchState = If(isDetectionEvent2, switchState.SetWatchdogStartDropTime2(e.GetTimeStamp()).SetWatchdogDropPackets2(true), switchState);
// update the watchdog state
var isBurstOn1 = And(e.GetEventType() == burstEvent, e.GetPriorityClass() == 0);
var isBurstOn2 = And(e.GetEventType() == burstEvent, e.GetPriorityClass() == 1);
var stateBurst1 = switchState.AddPacket(Pair(e.GetTimeStamp(), Pair <byte, bool>(0, currentState.GetWatchdogDropPackets1())));
var stateBurst2 = switchState.AddPacket(Pair(e.GetTimeStamp(), Pair <byte, bool>(1, currentState.GetWatchdogDropPackets1())));
var isStormStartOn1 = And(e.GetEventType() == stormStartEvent, e.GetPriorityClass() == 0);
var isStormStartOn2 = And(e.GetEventType() == stormStartEvent, e.GetPriorityClass() == 1);
var stateStormStartOn1 = switchState.SetStormStartedTime1(e.GetTimeStamp());
var stateStormStartOn2 = switchState.SetStormStartedTime2(e.GetTimeStamp());
var isStormEndOn1 = And(e.GetEventType() == stormEndEvent, e.GetPriorityClass() == 0);
var isStormEndOn2 = And(e.GetEventType() == stormEndEvent, e.GetPriorityClass() == 1);
var stateStormEndOn1 = switchState.SetStormEndedTime1(e.GetTimeStamp());
var stateStormEndOn2 = switchState.SetStormEndedTime2(e.GetTimeStamp());
return(Cases(switchState,
(isStormStartOn1, stateStormStartOn1),
(isStormStartOn2, stateStormStartOn2),
(isStormEndOn1, stateStormEndOn1),
(isStormEndOn2, stateStormEndOn2),
(isBurstOn1, stateBurst1),
(isBurstOn2, stateBurst2)));
}
private static Zen <TReturn> ApplyOrderedRules <TInput, TReturn, TRule>(
Zen <TInput> input,
Zen <TReturn> deflt,
Func <TRule, Zen <TInput>, int, Zen <bool> > ruleMatch,
Func <TRule, Zen <TInput>, int, Zen <TInput> > ruleAction,
Func <TRule, Zen <TInput>, int, Zen <Option <TReturn> > > ruleReturn,
TRule[] rules,
int i)
{
if (i == rules.Length)
{
return(deflt);
}
var rule = rules[i];
// whether the current rule is a match
var match = ruleMatch(rule, input, i + 1);
// get the new value after modifications
var modifiedInput = If(match, ruleAction(rule, input, i + 1), input);
// whether or not we should return here
var ret = ruleReturn(rule, modifiedInput, i + 1);
var applyRest = ApplyOrderedRules(modifiedInput, deflt, ruleMatch, ruleAction, ruleReturn, rules, i + 1);
return(If(And(match, ret.HasValue()), ret.Value(), applyRest));
}
/// <summary>
/// Or operation of two Zen List of bool.
/// </summary>
/// <param name="ma">list a.</param>
/// <param name="mb">list b.</param>
/// <returns>list of a or b.</returns>
public static Zen <IList <bool> > Or(this Zen <IList <bool> > ma, Zen <IList <bool> > mb)
{
var index = mb.Length();
var ret = ma.Select(_ => Language.Or(ma.At(index -= 1).Value(), mb.At(index).Value()));
return(ret);
}
/// <summary>
/// Create label-ns mapping
/// hash of label as key, 'bitvector' of ns as value.
/// </summary>
/// <param name="namespaces">all namespaces.</param>
/// <returns>label-ns mapping.</returns>
public static Zen <IDictionary <int, IList <bool> > > CreateNSLabelMatrix(Zen <Namespace>[] namespaces)
{
var n = namespaces.Length;
Dictionary <int, bool[]> labelHash = new Dictionary <int, bool[]>();
for (int i = 0; i < n; ++i)
{
var keys = namespaces[i].GetLabelKeys();
var k = keys.Length();
// iterate over Zen<List> to traverse all keys
for (k -= 1; !k.EqualToNumber(ushort.MaxValue); k -= 1)
{
var keyHash = keys.At(k).Value().GetHashCode();
if (!labelHash.ContainsKey(keyHash))
{
labelHash[keyHash] = new bool[n];
}
labelHash[keyHash][i] = true;
}
}
// create zen data.
Zen <IDictionary <int, IList <bool> > > mx = Language.EmptyDict <int, IList <bool> >();
foreach (var kv in labelHash)
{
mx = mx.Add(kv.Key, kv.Value);
}
return(mx);
}
/// <summary>
/// Find pods can only be reached from pods of same user.
/// </summary>
/// <param name="matrix">ingress reachability matrix.</param>
/// <param name="userHashmap">user-pod mapping.</param>
/// <param name="pods">all pods.</param>
/// <param name="userKey">key of user label.</param>
/// <returns>list of pods can only be reached from pods of same user.</returns>
public static Zen <IList <ushort> > UserCrossCheck(
Zen <IList <bool> >[] matrix,
Zen <IDictionary <int, IList <bool> > > userHashmap,
Zen <Pod>[] pods,
Zen <string> userKey)
{
var n = pods.Length;
Zen <IList <ushort> > podList = EmptyList <ushort>();
for (int i = 0; i < n; ++i)
{
var userString = pods[i].LabelValue(userKey);
if (userString == null)
{
continue;
}
var veriSet = userHashmap.Get(userString.GetHashCode()).Value();
veriSet = veriSet.Not().And(matrix[i]);
var c = If <ushort>(veriSet.All(r => r.Equals(False())), (ushort)i, ushort.MaxValue);
// if this pod can only be reached from same user's pods, add it to list
if (!c.EqualToNumber(ushort.MaxValue))
{
podList = podList.AddBack(c);
}
}
return(podList);
}
/// <summary>
/// Create a Zen packet from headers.
/// </summary>
/// <param name="overlayHeader">Overlay header.</param>
/// <param name="underlayHeader">Underlay header.</param>
/// <returns>Zen packet.</returns>
public static Zen <Packet> Create(
Zen <IpHeader> overlayHeader,
Zen <Option <IpHeader> > underlayHeader)
{
return(Language.Create <Packet>(
("OverlayHeader", overlayHeader),
("UnderlayHeader", underlayHeader)));
}
/// <summary>
/// A pairwise invariant for a list of elements.
/// </summary>
/// <param name="list">The list.</param>
/// <param name="f">The pairwise invariant.</param>
/// <returns>A zen value for the invariant.</returns>
internal static Zen <bool> PairwiseInvariant <T>(Zen <IList <T> > list, Func <Zen <T>, Zen <T>, Zen <bool> > f)
{
return(list.Case(
empty: true,
cons: (hd1, tl1) => tl1.Case(
empty: true,
cons: (hd2, tl2) => And(f(hd1, hd2), PairwiseInvariant(tl1, f)))));
}
/// <summary>
/// Get if this policy allows all traffic.
/// </summary>
/// <param name="policy">policy.</param>
/// <returns>if it is an allow-all policy.</returns>
public static bool GetAllowAll(this Zen <Policy> policy)
{
var labelKeys = policy.GetAllowKeys().Length();
var nsKeys = policy.GetAllowNSKeys().Length();
var denyAll = policy.GetDenyAll();
return(labelKeys.EqualToNumber(0) && nsKeys.EqualToNumber(0) && denyAll.Equals(False()));
}
public void PolicyShadowTest()
{
Zen <Pod>[] pods = new Zen <Pod>[]
{
Pod.Create("default", EmptyDict <string, string>().Add("k0", "v0").Add("k1", "v1"), EmptyList <string>().AddBack("k0").AddBack("k1")),
Pod.Create("default", EmptyDict <string, string>().Add("k1", "v1"), EmptyList <string>().AddBack("k1")),
Pod.Create("ns1", EmptyDict <string, string>().Add("k2", "v2"), EmptyList <string>().AddBack("k2")),
Pod.Create("ns1", EmptyDict <string, string>().Add("k3", "v3"), EmptyList <string>().AddBack("k3"))
};
Zen <Namespace>[] namespaces = new Zen <Namespace>[]
{
Namespace.Create("default", EmptyDict <string, string>().Add("k0", "v0"), EmptyList <string>().AddBack("k0")),
Namespace.Create("ns1", EmptyDict <string, string>().Add("k1", "v1"), EmptyList <string>().AddBack("k1"))
};
Zen <Policy>[] policies = new Zen <Policy>[]
{
Policy.Create("default", EmptyDict <string, string>().Add("k0", "v0").Add("k1", "v1"),
EmptyDict <string, string>().Add("k2", "v2"), EmptyDict <string, string>().Add("k1", "v1"),
EmptyList <string>().AddBack("k0").AddBack("k1"), EmptyList <string>().AddBack("k2"), EmptyList <string>().AddBack("k1")),
Policy.Create("default", EmptyDict <string, string>().Add("k1", "v1"),
EmptyDict <string, string>(), EmptyDict <string, string>().Add("k1", "v1"),
EmptyList <string>().AddBack("k1"), EmptyList <string>(), EmptyList <string>().AddBack("k1")),
Policy.Create("ns1", EmptyDict <string, string>().Add("k3", "v3"),
EmptyDict <string, string>().Add("k2", "v2"), EmptyDict <string, string>().Add("k0", "v0"),
EmptyList <string>().AddBack("k3"), EmptyList <string>().AddBack("k2"), EmptyList <string>().AddBack("k0")),
};
var podPolMx = Algorithms.CreateReachMatrix(pods, policies, namespaces).podPolMatrix;
var r0 = EmptyList <bool>().AddBack(true).AddBack(true).AddBack(false);
var r1 = EmptyList <bool>().AddBack(false).AddBack(true).AddBack(false);
var r2 = EmptyList <bool>().AddBack(false).AddBack(false).AddBack(false);
var r3 = EmptyList <bool>().AddBack(false).AddBack(false).AddBack(true);
TestHelper.AssertMatrixEqual(podPolMx, new Zen <IList <bool> >[] { r0, r1, r2, r3 }, "PolicyShadowTest: PodPolMatrix");
var polPodAllowedMx = Algorithms.CreateReachMatrix(pods, policies, namespaces).polPodAllowedMatrix;
r0 = EmptyList <bool>().AddBack(false).AddBack(false).AddBack(true).AddBack(false);
r1 = EmptyList <bool>().AddBack(false).AddBack(false).AddBack(true).AddBack(true);
r2 = EmptyList <bool>().AddBack(false).AddBack(false).AddBack(false).AddBack(false);
TestHelper.AssertMatrixEqual(polPodAllowedMx, new Zen <IList <bool> >[] { r0, r1, r2 }, "PolicyShadowTest: PolPodAllowedMatrix");
var polPodSelectedMx = Algorithms.CreateReachMatrix(pods, policies, namespaces).polPodSelectedMatrix;
r0 = EmptyList <bool>().AddBack(true).AddBack(false).AddBack(false).AddBack(false);
r1 = EmptyList <bool>().AddBack(true).AddBack(true).AddBack(false).AddBack(false);
r2 = EmptyList <bool>().AddBack(false).AddBack(false).AddBack(false).AddBack(true);
TestHelper.AssertMatrixEqual(polPodSelectedMx, new Zen <IList <bool> >[] { r0, r1, r2 }, "PolicyShadowTest: PolPodSelectedMatrix");
var shadowedPair = Verifier.PolicyShadowCheck(podPolMx, polPodAllowedMx, polPodSelectedMx);
Assert.IsTrue(shadowedPair.Length().EqualToNumber(1));
var expected = EmptyList <Tuple <int, int> >().AddBack(Tuple <int, int>(1, 0));
Assert.IsTrue(shadowedPair.ToString().Equals(expected.ToString()), "PolicyShadowTest: shadow pairs are not correct.\nExpected: {0}\nGot: {1}", expected.ToString(), shadowedPair.ToString());
}
/// <summary>
/// Create a model checker.
/// </summary>
/// <param name="backend">The backend to use.</param>
/// <param name="expression">The expression to evaluate.</param>
/// <returns>A new model checker.</returns>
internal static IModelChecker CreateModelChecker(Backend backend, Zen <bool> expression)
{
if (backend == Backend.DecisionDiagrams)
{
return(CreateModelCheckerDD(expression));
}
return(CreateModelCheckerZ3());
}
public static void Main()
{
Maruthi m = new Maruthi();
m = new Esteem(); //upcasting
m.Display();
m = new Zen(); //upcasting
m.Display();
}
/// <summary>
/// Create a model checker based on decision diagrams.
/// </summary>
/// <param name="expression"></param>
/// <returns></returns>
private static IModelChecker CreateModelCheckerDD(Zen <bool> expression)
{
var heuristic = new InterleavingHeuristic();
var mustInterleave = heuristic.Compute(expression);
var manager = new DDManager <BDDNode>(new BDDNodeFactory());
var solver = new SolverDD <BDDNode>(manager, mustInterleave);
solver.Init();
return(new ModelChecker <Assignment <BDDNode>, Variable <BDDNode>, DD, BitVector <BDDNode>, Unit>(solver));
}
/// <summary>
/// Match a packet with this acl.
/// </summary>
/// <param name="packet">The packet.</param>
/// <returns>Whether accepted.</returns>
public Zen <bool> Match(Zen <Packet> packet)
{
var dstIp = packet.GetDstIp();
var srcIp = packet.GetSrcIp();
return(And(dstIp >= this.DstIpLow,
dstIp <= this.DstIpHigh,
srcIp >= this.SrcIpLow,
srcIp <= this.SrcIpHigh));
}
/// <summary>
/// Match a packet and get the line number of the match.
/// </summary>
/// <param name="packet">The packet.</param>
/// <returns>Whether accepting and the line number of the match.</returns>
public Zen <Tuple <bool, ushort> > MatchProvenance(Zen <Packet> packet)
{
return(TestHelper.ApplyOrderedRules(
input: packet,
deflt: Tuple <bool, ushort>(false, this.Lines.Length + 1),
ruleMatch: (l, pkt, i) => l.Match(pkt),
ruleAction: (l, pkt, i) => pkt,
ruleReturn: (l, pkt, i) => Some(Tuple <bool, ushort>(l.Permitted, i)),
rules: this.Lines));
}
/// <summary>
/// Apply a collection or rules in order.
/// </summary>
/// <typeparam name="TInput">Input type.</typeparam>
/// <typeparam name="TReturn">Return type.</typeparam>
/// <typeparam name="TRule">Rule type.</typeparam>
/// <param name="input">Initial input.</param>
/// <param name="deflt">Default return.</param>
/// <param name="ruleMatch">Whether a rule matches.</param>
/// <param name="ruleAction">What action to apply if a match.</param>
/// <param name="ruleReturn">Whether and what to return at a rule.</param>
/// <param name="rules">The collection of rules.</param>
/// <returns></returns>
public static Zen <TReturn> ApplyOrderedRules <TInput, TReturn, TRule>(
Zen <TInput> input,
Zen <TReturn> deflt,
Func <TRule, Zen <TInput>, int, Zen <bool> > ruleMatch,
Func <TRule, Zen <TInput>, int, Zen <TInput> > ruleAction,
Func <TRule, Zen <TInput>, int, Zen <Option <TReturn> > > ruleReturn,
TRule[] rules)
{
return(ApplyOrderedRules(input, deflt, ruleMatch, ruleAction, ruleReturn, rules, 0));
}
public Zen <Option <SimplePacket> > ForwardInAndOut(Zen <SimplePacket> p, Zen <Ip> nextHop)
{
Zen <bool> hasPath = False();
foreach (Route r in RoutingTable)
{
hasPath = Or(r.NextHop == nextHop, hasPath);
}
return(If(hasPath, Some(p), Null <SimplePacket>()));
}
/// <summary>
/// Checks if a given packet matches this rule.
/// </summary>
/// <param name="packet">The packet to test.</param>
/// <returns>True if the packet matches; otherwise false.</returns>
public Zen <bool> Matches(Zen <Packet> packet)
{
// TODO: If ports are zero, do NOT include in predicate (zero implies "ANY")
return(And(packet.GetDstIp() >= this.DstIpLow,
packet.GetDstIp() <= this.DstIpHigh,
packet.GetDstPort() == this.DstPort,
packet.GetSrcIp() >= this.SrcIpLow,
packet.GetSrcIp() <= this.SrcIpHigh,
packet.GetSrcPort() == this.SrcPort));
}
public Zen <Boolean> Forward(Zen <SimplePacket> p, Zen <IList <Tuple <int, int> > > failedLinks)
{
// path generation
HashSet <List <int> > pathSet = new HashSet <List <int> >();
for (int i = 0; i < nodes.Count; i++)
{
for (int j = 0; j < nodes.Count; j++)
{
var nextHopIp = nodes[i].getNextHop(nodes[j].Address);
if (nextHopIp.Value != GlobalVar.NULL_IP.Value)
{
// there is a route
List <int> currRoute = new List <int>();
currRoute.Add(i);
var currCost = 0;
while (nextHopIp.Value != GlobalVar.NULL_IP.Value &&
nextHopIp.Value != nodes[j].Address.Value)
{
currRoute.Add((int)nextHopIp.Value);
nextHopIp = nodes[(int)nextHopIp.Value].getNextHop(nodes[j].Address);
currCost += 1;
}
currRoute.Add(j);
if (currCost < this.maxCost && !currRoute.Contains((int)this.intermediateNode.Value))
{
pathSet.Add(currRoute);
// Console.WriteLine("Adding path " + nodes[i].Address + " " + nodes[j].Address);
}
}
}
}
//var a = new List<int>() { 1, 2 };
//pathSet.Add(a);
// forwarding w/ Zen
Zen <Boolean> forwardSuccess = False();
foreach (List <int> path in pathSet)
{
var startNode = nodes[path[0]];
var endNode = nodes[path[path.Count - 1]];
forwardSuccess = If(And(p.GetSrcIp() == startNode.Address, p.GetDstIp() == endNode.Address),
Forward(path.ToArray(), p, failedLinks).HasValue(),
forwardSuccess);
}
//Console.WriteLine("Final Expression:");
//Console.WriteLine(forwardSuccess);
//Console.WriteLine();
return(forwardSuccess);
}
private Zen <LocatedPacket> StepMany(Zen <LocatedPacket> initial, int k)
{
if (k == 0)
{
return(initial);
}
var newLp = StepOnce(initial);
return(If(newLp.HasValue(), StepMany(newLp.Value(), k - 1), initial));
}
private Zen <Option <LocatedPacket> > StepOnce(Zen <LocatedPacket> lp)
{
var location = lp.GetNode();
var packet = lp.GetHeader();
return(If(location == 0,
Some(LocatedPacketHelper.Create(1, packet)),
If(location == 1,
Some(LocatedPacketHelper.Create(2, packet)),
Null <LocatedPacket>())));
}
/// <summary>
/// Process a header on an acl.
/// </summary>
/// <param name="hdr">The header.</param>
/// <param name="i">The line number.</param>
/// <returns>Whether permitted.</returns>
public Zen <bool> Process(Zen <IpHeader> hdr, int i)
{
if (i == this.Lines.Length)
{
return(false);
}
var line = this.Lines[i];
return(If(line.Matches(hdr), line.Permitted, Process(hdr, i + 1)));
}
