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

Example 31 with GraphEdge

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

the class Optimizations method computeRouterIdNeeded.

/*
   * Check if we need to model the router ID
   */
private void computeRouterIdNeeded() {
    _encoderSlice.getGraph().getConfigurations().forEach((router, conf) -> {
        // If iBGP is used, and no multipath, then we need the routerId
        boolean usesIbgp = false;
        for (GraphEdge ge : _encoderSlice.getGraph().getEdgeMap().get(router)) {
            if (_encoderSlice.getGraph().getIbgpNeighbors().get(ge) != null) {
                usesIbgp = true;
                break;
            }
        }
        // If eBGP is used, and no multipath, then we need the routerId
        boolean usesEbgp = _encoderSlice.getProtocols().get(router).contains(Protocol.BGP);
        // check if multipath is used
        boolean ibgpMultipath = false;
        boolean ebgpMultipath = false;
        BgpProcess p = conf.getDefaultVrf().getBgpProcess();
        if (p != null) {
            ibgpMultipath = p.getMultipathIbgp();
            ebgpMultipath = p.getMultipathEbgp();
        }
        if ((usesIbgp && !ibgpMultipath) || (usesEbgp && !ebgpMultipath)) {
            _needRouterId.add(router);
        }
    });
}

Example 32 with GraphEdge

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

the class Optimizations method hasExportVariables.

/*
   * Check if a graph edge will have export variables for a given protocol.
   * This will happen when the edge's interface is used in the protocol
   * and the other end of the interface is internal.
   */
private boolean hasExportVariables(GraphEdge e, Protocol proto) {
    if (e.getEnd() != null) {
        String peer = e.getPeer();
        List<Protocol> peerProtocols = getProtocols().get(peer);
        if (peerProtocols.contains(proto)) {
            Configuration peerConf = _encoderSlice.getGraph().getConfigurations().get(peer);
            GraphEdge other = _encoderSlice.getGraph().getOtherEnd().get(e);
            if (_encoderSlice.getGraph().isEdgeUsed(peerConf, proto, other)) {
                return true;
            }
        }
    }
    return false;
}

Example 33 with GraphEdge

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

the class Optimizations method computeCanMergeImportExportVars.

/*
   * Determine when import and export variables can be merged along an edge.
   * This will be safe when there is no peer-specific import filter
   */
private void computeCanMergeImportExportVars() {
    _encoderSlice.getGraph().getConfigurations().forEach((router, conf) -> {
        Map<Protocol, List<GraphEdge>> map = new HashMap<>();
        _sliceCanCombineImportExportVars.put(router, map);
        for (Protocol proto : getProtocols().get(router)) {
            List<GraphEdge> edges = new ArrayList<>();
            if (Optimizations.ENABLE_IMPORT_EXPORT_MERGE_OPTIMIZATION && !proto.isConnected() && !proto.isStatic() && !proto.isOspf()) {
                for (GraphEdge ge : _encoderSlice.getGraph().getEdgeMap().get(router)) {
                    // Don't merge when an abstract edge is used.
                    boolean safeMergeEdge = _encoderSlice.getGraph().isEdgeUsed(conf, proto, ge) && !ge.isAbstract();
                    // Don't merge when bgp internal/external can differ
                    boolean sameInternal = (ge.getPeer() == null) || (_needBgpInternal.contains(router) == _needBgpInternal.contains(ge.getPeer()));
                    // Check if there are any local modifications on import
                    boolean isPure = true;
                    RoutingPolicy pol = _encoderSlice.getGraph().findImportRoutingPolicy(router, proto, ge);
                    if (pol != null) {
                        isPure = false;
                    }
                    boolean noFailures = _encoderSlice.getEncoder().getFailures() == 0;
                    if (safeMergeEdge && sameInternal && isPure && noFailures && hasExportVariables(ge, proto)) {
                        edges.add(ge);
                    }
                }
            }
            map.put(proto, edges);
        }
    });
}

Example 34 with GraphEdge

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

the class PropertyAdder method instrumentLoad.

/*
   * Instruments the network with load balancing information to destination
   * port for graph edge ge. Each router will split load according to the
   * number of neighbors it actively uses to get to ge.
   */
Map<String, ArithExpr> instrumentLoad(Set<GraphEdge> ges) {
    Context ctx = _encoderSlice.getCtx();
    Solver solver = _encoderSlice.getSolver();
    String sliceName = _encoderSlice.getSliceName();
    Map<String, ArithExpr> loadVars = new HashMap<>();
    Graph graph = _encoderSlice.getGraph();
    for (String router : graph.getRouters()) {
        String name = _encoderSlice.getEncoder().getId() + "_" + sliceName + "_load_" + router;
        ArithExpr var = ctx.mkIntConst(name);
        loadVars.put(router, var);
        _encoderSlice.getAllVariables().put(var.toString(), var);
    }
    loadVars.forEach((name, var) -> solver.add(ctx.mkGe(var, ctx.mkInt(0))));
    ArithExpr zero = ctx.mkInt(0);
    ArithExpr one = ctx.mkInt(1);
    for (Entry<String, List<GraphEdge>> entry : graph.getEdgeMap().entrySet()) {
        String router = entry.getKey();
        List<GraphEdge> edges = entry.getValue();
        ArithExpr load = loadVars.get(router);
        BoolExpr hasDirectRoute = ctx.mkFalse();
        BoolExpr isAbsorbed = ctx.mkFalse();
        SymbolicRoute r = _encoderSlice.getBestNeighborPerProtocol(router, Protocol.CONNECTED);
        for (GraphEdge ge : edges) {
            if (!ge.isAbstract() && ges.contains(ge)) {
                // if we leave the network
                if (ge.getPeer() == null) {
                    BoolExpr fwdIface = _encoderSlice.getForwardsAcross().get(ge.getRouter(), ge);
                    assert (fwdIface != null);
                    hasDirectRoute = ctx.mkOr(hasDirectRoute, fwdIface);
                }
                // if connected route and we use it despite not forwarding
                if (r != null) {
                    BitVecExpr dstIp = _encoderSlice.getSymbolicPacket().getDstIp();
                    BitVecExpr ip = ctx.mkBV(ge.getStart().getAddress().getIp().asLong(), 32);
                    BoolExpr reach = ctx.mkAnd(r.getPermitted(), ctx.mkEq(dstIp, ip));
                    isAbsorbed = ctx.mkOr(isAbsorbed, reach);
                }
            }
        }
        ArithExpr acc = ctx.mkInt(0);
        for (GraphEdge edge : edges) {
            if (!edge.isAbstract()) {
                BoolExpr fwd = _encoderSlice.getForwardsAcross().get(router, edge);
                assert (fwd != null);
                if (edge.getPeer() != null) {
                    ArithExpr peerLoad = loadVars.get(edge.getPeer());
                    ArithExpr x = (ArithExpr) ctx.mkITE(fwd, peerLoad, zero);
                    acc = ctx.mkAdd(acc, x);
                }
            }
        }
        solver.add(ctx.mkEq(load, acc));
        BoolExpr guard = _encoderSlice.mkOr(hasDirectRoute, isAbsorbed);
        BoolExpr cond = _encoderSlice.mkIf(guard, ctx.mkEq(load, one), ctx.mkEq(load, acc));
        solver.add(cond);
    }
    return loadVars;
}

Example 35 with GraphEdge

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

the class PropertyAdder method instrumentReachability.

/*
   * Also instruments reachability, but to a destination router
   * rather than a destination port.
   */
Map<String, BoolExpr> instrumentReachability(String router) {
    Context ctx = _encoderSlice.getCtx();
    Solver solver = _encoderSlice.getSolver();
    Map<String, BoolExpr> reachableVars = new HashMap<>();
    Map<String, ArithExpr> idVars = new HashMap<>();
    initializeReachabilityVars(_encoderSlice, ctx, solver, reachableVars, idVars);
    ArithExpr baseId = idVars.get(router);
    _encoderSlice.add(ctx.mkEq(baseId, ctx.mkInt(1)));
    Graph g = _encoderSlice.getGraph();
    for (Entry<String, List<GraphEdge>> entry : g.getEdgeMap().entrySet()) {
        String r = entry.getKey();
        List<GraphEdge> edges = entry.getValue();
        if (!r.equals(router)) {
            ArithExpr id = idVars.get(r);
            BoolExpr cond = recursiveReachability(ctx, _encoderSlice, edges, idVars, r, id);
            solver.add(cond);
        }
    }
    return reachableVars;
}