Examples with Protocol org.batfish.symbolic.Protocol used on opensource projects

Example 26 with Protocol

use of org.batfish.symbolic.Protocol in project batfish by batfish.

the class PropertyChecker method checkLocalEquivalence.

/*
   * Computes whether or not two routers are equivalent.
   * To be equivalent, each router must have identical intefaces.
   *
   * We then relate the environments on each interface for each router
   * so that they are required to be equal.
   *
   * We finally check that their forwarding decisions and exported messages
   * will be equal given their equal inputs.
   */
public AnswerElement checkLocalEquivalence(Pattern n, boolean strict, boolean fullModel) {
    Graph graph = new Graph(_batfish);
    List<String> routers = PatternUtils.findMatchingNodes(graph, n, Pattern.compile(""));
    HeaderQuestion q = new HeaderQuestion();
    q.setFullModel(fullModel);
    q.setFailures(0);
    q.setBaseEnvironmentType(EnvironmentType.ANY);
    Collections.sort(routers);
    SortedMap<String, VerificationResult> result = new TreeMap<>();
    int len = routers.size();
    if (len <= 1) {
        return new SmtManyAnswerElement(new TreeMap<>());
    }
    for (int i = 0; i < len - 1; i++) {
        String r1 = routers.get(i);
        String r2 = routers.get(i + 1);
        // TODO: reorder to encode after checking if we can compare them
        // Create transfer function for router 1
        Set<String> toModel1 = new TreeSet<>();
        toModel1.add(r1);
        Graph g1 = new Graph(_batfish, null, toModel1);
        Encoder e1 = new Encoder(_settings, g1, q);
        e1.computeEncoding();
        Context ctx = e1.getCtx();
        // Create transfer function for router 2
        Set<String> toModel2 = new TreeSet<>();
        toModel2.add(r2);
        Graph g2 = new Graph(_batfish, null, toModel2);
        Encoder e2 = new Encoder(e1, g2);
        e2.computeEncoding();
        EncoderSlice slice1 = e1.getMainSlice();
        EncoderSlice slice2 = e2.getMainSlice();
        // Ensure that the two routers have the same interfaces for comparison
        Pattern p = Pattern.compile(".*");
        Pattern neg = Pattern.compile("");
        List<GraphEdge> edges1 = PatternUtils.findMatchingEdges(g1, p, neg, p, neg);
        List<GraphEdge> edges2 = PatternUtils.findMatchingEdges(g2, p, neg, p, neg);
        Set<String> ifaces1 = interfaces(edges1);
        Set<String> ifaces2 = interfaces(edges2);
        if (!(ifaces1.containsAll(ifaces2) && ifaces2.containsAll(ifaces1))) {
            String msg = String.format("Routers %s and %s have different interfaces", r1, r2);
            System.out.println(msg);
            return new SmtManyAnswerElement(new TreeMap<>());
        }
        // TODO: check running same protocols?
        Map<String, Map<Protocol, Map<String, EnumMap<EdgeType, LogicalEdge>>>> lgeMap2 = logicalEdgeMap(slice2);
        BoolExpr equalEnvs = ctx.mkBool(true);
        BoolExpr equalOutputs = ctx.mkBool(true);
        BoolExpr equalIncomingAcls = ctx.mkBool(true);
        Configuration conf1 = g1.getConfigurations().get(r1);
        Configuration conf2 = g2.getConfigurations().get(r2);
        // Set environments equal
        Set<String> communities = new HashSet<>();
        Set<SymbolicRoute> envRecords = new HashSet<>();
        for (Protocol proto1 : slice1.getProtocols().get(r1)) {
            for (ArrayList<LogicalEdge> es : slice1.getLogicalGraph().getLogicalEdges().get(r1).get(proto1)) {
                for (LogicalEdge lge1 : es) {
                    String ifaceName = lge1.getEdge().getStart().getName();
                    LogicalEdge lge2 = lgeMap2.get(r2).get(proto1).get(ifaceName).get(lge1.getEdgeType());
                    if (lge1.getEdgeType() == EdgeType.IMPORT) {
                        SymbolicRoute vars1 = slice1.getLogicalGraph().getEnvironmentVars().get(lge1);
                        SymbolicRoute vars2 = slice2.getLogicalGraph().getEnvironmentVars().get(lge2);
                        BoolExpr aclIn1 = slice1.getIncomingAcls().get(lge1.getEdge());
                        BoolExpr aclIn2 = slice2.getIncomingAcls().get(lge2.getEdge());
                        if (aclIn1 == null) {
                            aclIn1 = ctx.mkBool(true);
                        }
                        if (aclIn2 == null) {
                            aclIn2 = ctx.mkBool(true);
                        }
                        equalIncomingAcls = ctx.mkAnd(equalIncomingAcls, ctx.mkEq(aclIn1, aclIn2));
                        boolean hasEnv1 = (vars1 != null);
                        boolean hasEnv2 = (vars2 != null);
                        if (hasEnv1 && hasEnv2) {
                            BoolExpr samePermitted = ctx.mkEq(vars1.getPermitted(), vars2.getPermitted());
                            // Set communities equal
                            BoolExpr equalComms = e1.mkTrue();
                            for (Map.Entry<CommunityVar, BoolExpr> entry : vars1.getCommunities().entrySet()) {
                                CommunityVar cvar = entry.getKey();
                                BoolExpr ce1 = entry.getValue();
                                BoolExpr ce2 = vars2.getCommunities().get(cvar);
                                if (ce2 != null) {
                                    equalComms = e1.mkAnd(equalComms, e1.mkEq(ce1, ce2));
                                }
                            }
                            // Set communities belonging to one but not the other
                            // off, but give a warning of the difference
                            BoolExpr unsetComms = e1.mkTrue();
                            for (Map.Entry<CommunityVar, BoolExpr> entry : vars1.getCommunities().entrySet()) {
                                CommunityVar cvar = entry.getKey();
                                BoolExpr ce1 = entry.getValue();
                                BoolExpr ce2 = vars2.getCommunities().get(cvar);
                                if (ce2 == null) {
                                    if (!communities.contains(cvar.getValue())) {
                                        communities.add(cvar.getValue());
                                    /* String msg =
                       String.format(
                           "Warning: community %s found for router %s but not %s.",
                           cvar.getValue(), conf1.getEnvName(), conf2.getEnvName());
                      System.out.println(msg); */
                                    }
                                    unsetComms = e1.mkAnd(unsetComms, e1.mkNot(ce1));
                                }
                            }
                            // Do the same thing for communities missing from the other side
                            for (Map.Entry<CommunityVar, BoolExpr> entry : vars2.getCommunities().entrySet()) {
                                CommunityVar cvar = entry.getKey();
                                BoolExpr ce2 = entry.getValue();
                                BoolExpr ce1 = vars1.getCommunities().get(cvar);
                                if (ce1 == null) {
                                    if (!communities.contains(cvar.getValue())) {
                                        communities.add(cvar.getValue());
                                    /* String msg =
                       String.format(
                           "Warning: community %s found for router %s but not %s.",
                           cvar.getValue(), conf2.getEnvName(), conf1.getEnvName());
                      System.out.println(msg); */
                                    }
                                    unsetComms = e1.mkAnd(unsetComms, e1.mkNot(ce2));
                                }
                            }
                            envRecords.add(vars1);
                            BoolExpr equalVars = slice1.equal(conf1, proto1, vars1, vars2, lge1, true);
                            equalEnvs = ctx.mkAnd(equalEnvs, unsetComms, samePermitted, equalVars, equalComms);
                        } else if (hasEnv1 || hasEnv2) {
                            System.out.println("Edge1: " + lge1);
                            System.out.println("Edge2: " + lge2);
                            throw new BatfishException("one had environment");
                        }
                    } else {
                        SymbolicRoute out1 = lge1.getSymbolicRecord();
                        SymbolicRoute out2 = lge2.getSymbolicRecord();
                        equalOutputs = ctx.mkAnd(equalOutputs, slice1.equal(conf1, proto1, out1, out2, lge1, false));
                    }
                }
            }
        }
        // check the stronger version of local equivalence
        if (strict) {
            for (SymbolicRoute env1 : envRecords) {
                for (SymbolicRoute env2 : envRecords) {
                    if (!env1.equals(env2)) {
                        BoolExpr c = e2.mkImplies(env1.getPermitted(), e2.mkNot(env2.getPermitted()));
                        e2.add(c);
                    }
                }
            }
        }
        // TODO: check both have same environment vars (e.g., screw up configuring peer connection)
        // Create assumptions
        BoolExpr validDest;
        validDest = ignoredDestinations(ctx, slice1, r1, conf1);
        validDest = ctx.mkAnd(validDest, ignoredDestinations(ctx, slice2, r2, conf2));
        SymbolicPacket p1 = slice1.getSymbolicPacket();
        SymbolicPacket p2 = slice2.getSymbolicPacket();
        BoolExpr equalPackets = p1.mkEqual(p2);
        BoolExpr assumptions = ctx.mkAnd(equalEnvs, equalPackets, validDest);
        // Create the requirements
        // Best choices should be the same
        BoolExpr required;
        if (strict) {
            SymbolicRoute best1 = e1.getMainSlice().getSymbolicDecisions().getBestNeighbor().get(conf1.getName());
            SymbolicRoute best2 = e2.getMainSlice().getSymbolicDecisions().getBestNeighbor().get(conf2.getName());
            // Just pick some protocol for defaults, shouldn't matter for best choice
            required = equal(e2, conf2, best1, best2);
        } else {
            // Forwarding decisions should be the sames
            Map<String, GraphEdge> geMap2 = interfaceMap(edges2);
            BoolExpr sameForwarding = ctx.mkBool(true);
            for (GraphEdge ge1 : edges1) {
                GraphEdge ge2 = geMap2.get(ge1.getStart().getName());
                BoolExpr dataFwd1 = slice1.getSymbolicDecisions().getDataForwarding().get(r1, ge1);
                BoolExpr dataFwd2 = slice2.getSymbolicDecisions().getDataForwarding().get(r2, ge2);
                assert (dataFwd1 != null);
                assert (dataFwd2 != null);
                sameForwarding = ctx.mkAnd(sameForwarding, ctx.mkEq(dataFwd1, dataFwd2));
            }
            // equalOutputs, equalIncomingAcls);
            required = ctx.mkAnd(sameForwarding);
        }
        e2.add(assumptions);
        e2.add(ctx.mkNot(required));
        VerificationResult res = e2.verify().getFirst();
        String name = r1 + "<-->" + r2;
        result.put(name, res);
    }
    return new SmtManyAnswerElement(result);
}

Example 27 with Protocol

use of org.batfish.symbolic.Protocol in project batfish by batfish.

the class TransferSSA method compute.

/*
   * Convert a Batfish AST boolean expression to a symbolic Z3 boolean expression
   * by performing inlining of stateful side effects.
   */
private TransferResult<BoolExpr, BoolExpr> compute(BooleanExpr expr, TransferParam<SymbolicRoute> p) {
    // TODO: right now everything is IPV4
    if (expr instanceof MatchIpv4) {
        p.debug("MatchIpv4");
        return fromExpr(_enc.mkTrue());
    }
    if (expr instanceof MatchIpv6) {
        p.debug("MatchIpv6");
        return fromExpr(_enc.mkFalse());
    }
    if (expr instanceof Conjunction) {
        p.debug("Conjunction");
        Conjunction c = (Conjunction) expr;
        BoolExpr acc = _enc.mkTrue();
        TransferResult<BoolExpr, BoolExpr> result = new TransferResult<>();
        for (BooleanExpr be : c.getConjuncts()) {
            TransferResult<BoolExpr, BoolExpr> r = compute(be, p.indent());
            result = result.addChangedVariables(r);
            acc = _enc.mkAnd(acc, r.getReturnValue());
        }
        p.debug("has changed variable");
        return result.setReturnValue(acc);
    }
    if (expr instanceof Disjunction) {
        p.debug("Disjunction");
        Disjunction d = (Disjunction) expr;
        BoolExpr acc = _enc.mkFalse();
        TransferResult<BoolExpr, BoolExpr> result = new TransferResult<>();
        for (BooleanExpr be : d.getDisjuncts()) {
            TransferResult<BoolExpr, BoolExpr> r = compute(be, p.indent());
            result = result.addChangedVariables(r);
            acc = _enc.mkOr(acc, r.getReturnValue());
        }
        p.debug("has changed variable");
        return result.setReturnValue(acc);
    }
    if (expr instanceof ConjunctionChain) {
        p.debug("ConjunctionChain");
        ConjunctionChain d = (ConjunctionChain) expr;
        List<BooleanExpr> conjuncts = new ArrayList<>(d.getSubroutines());
        if (p.getDefaultPolicy() != null) {
            BooleanExpr be = new CallExpr(p.getDefaultPolicy().getDefaultPolicy());
            conjuncts.add(be);
        }
        if (conjuncts.size() == 0) {
            return fromExpr(_enc.mkTrue());
        } else {
            TransferResult<BoolExpr, BoolExpr> result = new TransferResult<>();
            BoolExpr acc = _enc.mkFalse();
            for (int i = conjuncts.size() - 1; i >= 0; i--) {
                BooleanExpr conjunct = conjuncts.get(i);
                TransferParam<SymbolicRoute> param = p.setDefaultPolicy(null).setChainContext(TransferParam.ChainContext.CONJUNCTION);
                TransferResult<BoolExpr, BoolExpr> r = compute(conjunct, param);
                result = result.addChangedVariables(r);
                acc = _enc.mkIf(r.getFallthroughValue(), acc, r.getReturnValue());
            }
            p.debug("ConjunctionChain Result: " + acc);
            return result.setReturnValue(acc);
        }
    }
    if (expr instanceof DisjunctionChain) {
        p.debug("DisjunctionChain");
        DisjunctionChain d = (DisjunctionChain) expr;
        List<BooleanExpr> disjuncts = new ArrayList<>(d.getSubroutines());
        if (p.getDefaultPolicy() != null) {
            BooleanExpr be = new CallExpr(p.getDefaultPolicy().getDefaultPolicy());
            disjuncts.add(be);
        }
        if (disjuncts.size() == 0) {
            return fromExpr(_enc.mkTrue());
        } else {
            TransferResult<BoolExpr, BoolExpr> result = new TransferResult<>();
            BoolExpr acc = _enc.mkFalse();
            for (int i = disjuncts.size() - 1; i >= 0; i--) {
                BooleanExpr disjunct = disjuncts.get(i);
                TransferParam<SymbolicRoute> param = p.setDefaultPolicy(null).setChainContext(TransferParam.ChainContext.CONJUNCTION);
                TransferResult<BoolExpr, BoolExpr> r = compute(disjunct, param);
                result.addChangedVariables(r);
                acc = _enc.mkIf(r.getFallthroughValue(), acc, r.getReturnValue());
            }
            p.debug("DisjunctionChain Result: " + acc);
            return result.setReturnValue(acc);
        }
    }
    if (expr instanceof Not) {
        p.debug("mkNot");
        Not n = (Not) expr;
        TransferResult<BoolExpr, BoolExpr> result = compute(n.getExpr(), p);
        return result.setReturnValue(_enc.mkNot(result.getReturnValue()));
    }
    if (expr instanceof MatchProtocol) {
        MatchProtocol mp = (MatchProtocol) expr;
        Protocol proto = Protocol.fromRoutingProtocol(mp.getProtocol());
        if (proto == null) {
            p.debug("MatchProtocol(" + mp.getProtocol().protocolName() + "): false");
            return fromExpr(_enc.mkFalse());
        }
        if (_other.getProtocolHistory() == null) {
            BoolExpr protoMatch = _enc.mkBool(proto.equals(_proto));
            p.debug("MatchProtocol(" + mp.getProtocol().protocolName() + "): " + protoMatch);
            return fromExpr(protoMatch);
        }
        BoolExpr protoMatch = _other.getProtocolHistory().checkIfValue(proto);
        p.debug("MatchProtocol(" + mp.getProtocol().protocolName() + "): " + protoMatch);
        return fromExpr(protoMatch);
    }
    if (expr instanceof MatchPrefixSet) {
        p.debug("MatchPrefixSet");
        MatchPrefixSet m = (MatchPrefixSet) expr;
        // For BGP, may change prefix length
        TransferResult<BoolExpr, BoolExpr> result = matchPrefixSet(_conf, m.getPrefixSet(), p.getData());
        return result.setReturnAssignedValue(_enc.mkTrue());
    // TODO: implement me
    } else if (expr instanceof MatchPrefix6Set) {
        p.debug("MatchPrefix6Set");
        return fromExpr(_enc.mkFalse());
    } else if (expr instanceof CallExpr) {
        p.debug("CallExpr");
        // TODO: the call can modify certain fields, need to keep track of these variables
        CallExpr c = (CallExpr) expr;
        String name = c.getCalledPolicyName();
        RoutingPolicy pol = _conf.getRoutingPolicies().get(name);
        p = p.setCallContext(TransferParam.CallContext.EXPR_CALL);
        TransferResult<BoolExpr, BoolExpr> r = compute(pol.getStatements(), p.indent().enterScope(name), initialResult());
        p.debug("CallExpr (return): " + r.getReturnValue());
        p.debug("CallExpr (fallthrough): " + r.getFallthroughValue());
        return r;
    } else if (expr instanceof WithEnvironmentExpr) {
        p.debug("WithEnvironmentExpr");
        // TODO: this is not correct
        WithEnvironmentExpr we = (WithEnvironmentExpr) expr;
        // TODO: postStatements() and preStatements()
        return compute(we.getExpr(), p);
    } else if (expr instanceof MatchCommunitySet) {
        p.debug("MatchCommunitySet");
        MatchCommunitySet mcs = (MatchCommunitySet) expr;
        return fromExpr(matchCommunitySet(_conf, mcs.getExpr(), p.getData()));
    } else if (expr instanceof BooleanExprs.StaticBooleanExpr) {
        BooleanExprs.StaticBooleanExpr b = (BooleanExprs.StaticBooleanExpr) expr;
        switch(b.getType()) {
            case CallExprContext:
                p.debug("CallExprContext");
                return fromExpr(_enc.mkBool(p.getCallContext() == TransferParam.CallContext.EXPR_CALL));
            case CallStatementContext:
                p.debug("CallStmtContext");
                return fromExpr(_enc.mkBool(p.getCallContext() == TransferParam.CallContext.STMT_CALL));
            case True:
                p.debug("True");
                return fromExpr(_enc.mkTrue());
            case False:
                p.debug("False");
                return fromExpr(_enc.mkFalse());
            default:
                throw new BatfishException("Unhandled " + BooleanExprs.class.getCanonicalName() + ": " + b.getType());
        }
    } else if (expr instanceof MatchAsPath) {
        p.debug("MatchAsPath");
        System.out.println("Warning: use of unimplemented feature MatchAsPath");
        return fromExpr(_enc.mkFalse());
    }
    String s = (_isExport ? "export" : "import");
    String msg = String.format("Unimplemented feature %s for %s transfer function on interface %s", expr.toString(), s, _graphEdge.toString());
    throw new BatfishException(msg);
}