Examples with BoolExpr com.microsoft.z3.BoolExpr used on opensource projects

Example 51 with BoolExpr

use of com.microsoft.z3.BoolExpr in project batfish by batfish.

the class EncoderSlice method computeValidRange.

/*
   * Convert a set of ranges and a packet field to a symbolic boolean expression
   */
private BoolExpr computeValidRange(Set<SubRange> ranges, ArithExpr field) {
    BoolExpr acc = mkFalse();
    for (SubRange range : ranges) {
        int start = range.getStart();
        int end = range.getEnd();
        if (start == end) {
            BoolExpr val = mkEq(field, mkInt(start));
            acc = mkOr(acc, val);
        } else {
            BoolExpr val1 = mkGe(field, mkInt(start));
            BoolExpr val2 = mkLe(field, mkInt(end));
            acc = mkOr(acc, mkAnd(val1, val2));
        }
    }
    return (BoolExpr) acc.simplify();
}

Example 52 with BoolExpr

use of com.microsoft.z3.BoolExpr in project batfish by batfish.

the class EncoderSlice method addDataForwardingConstraints.

/*
   * Constraints for the final data plane forwarding behavior.
   * Forwarding occurs in the data plane if the control plane decides
   * to use an interface, and no ACL blocks the packet:
   *
   * data_fwd(iface) = control_fwd(iface) and not acl(iface)
   */
private void addDataForwardingConstraints() {
    for (Entry<String, List<GraphEdge>> entry : getGraph().getEdgeMap().entrySet()) {
        String router = entry.getKey();
        List<GraphEdge> edges = entry.getValue();
        for (GraphEdge ge : edges) {
            // setup forwarding for non-abstract edges
            if (!ge.isAbstract()) {
                BoolExpr fwd = mkFalse();
                BoolExpr cForward = _symbolicDecisions.getControlForwarding().get(router, ge);
                BoolExpr dForward = _symbolicDecisions.getDataForwarding().get(router, ge);
                assert (cForward != null);
                assert (dForward != null);
                // out the current edge ge, the we use ge.
                for (GraphEdge ge2 : getGraph().getEdgeMap().get(router)) {
                    if (ge2.isAbstract()) {
                        BoolExpr ctrlFwd = getSymbolicDecisions().getControlForwarding().get(router, ge2);
                        Graph.BgpSendType st = getGraph().peerType(ge2);
                        // If Route reflectors, then next hop based on ID
                        if (st == Graph.BgpSendType.TO_RR) {
                            SymbolicRoute record = getSymbolicDecisions().getBestNeighbor().get(router);
                            // adjust for iBGP in main slice
                            BoolExpr acc = mkFalse();
                            if (isMainSlice()) {
                                for (Entry<String, Integer> entry2 : getGraph().getOriginatorId().entrySet()) {
                                    String r = entry2.getKey();
                                    Integer id = entry2.getValue();
                                    EncoderSlice s = _encoder.getSlice(r);
                                    // Make sure
                                    if (otherSliceHasEdge(s, router, ge)) {
                                        BoolExpr outEdge = s.getSymbolicDecisions().getDataForwarding().get(router, ge);
                                        acc = mkOr(acc, mkAnd(record.getClientId().checkIfValue(id), outEdge));
                                    }
                                }
                            }
                            fwd = mkOr(fwd, mkAnd(ctrlFwd, acc));
                        } else {
                            // adjust for iBGP in main slice
                            if (isMainSlice()) {
                                EncoderSlice s = _encoder.getSlice(ge2.getPeer());
                                if (otherSliceHasEdge(s, router, ge)) {
                                    BoolExpr outEdge = s.getSymbolicDecisions().getDataForwarding().get(router, ge);
                                    fwd = mkOr(fwd, mkAnd(ctrlFwd, outEdge));
                                }
                            }
                        }
                    }
                }
                fwd = mkOr(fwd, cForward);
                BoolExpr acl = _outboundAcls.get(ge);
                if (acl == null) {
                    acl = mkTrue();
                }
                BoolExpr notBlocked = mkAnd(fwd, acl);
                add(mkEq(notBlocked, dForward));
            }
        }
    }
}

Example 53 with BoolExpr

use of com.microsoft.z3.BoolExpr in project batfish by batfish.

the class EncoderSlice method computeACL.

/*
   * Convert an Access Control List (ACL) to a symbolic boolean expression.
   * The default action in an ACL is to deny all traffic.
   */
private BoolExpr computeACL(IpAccessList acl) {
    // Check if there is an ACL first
    if (acl == null) {
        return mkTrue();
    }
    BoolExpr acc = mkFalse();
    List<IpAccessListLine> lines = new ArrayList<>(acl.getLines());
    Collections.reverse(lines);
    for (IpAccessListLine l : lines) {
        BoolExpr local = null;
        if (l.getDstIps() != null) {
            BoolExpr val = computeWildcardMatch(l.getDstIps(), _symbolicPacket.getDstIp());
            val = l.getDstIps().isEmpty() ? mkTrue() : val;
            local = val;
        }
        if (l.getSrcIps() != null) {
            BoolExpr val = computeWildcardMatch(l.getSrcIps(), _symbolicPacket.getSrcIp());
            val = l.getDstIps().isEmpty() ? mkTrue() : val;
            local = (local == null ? val : mkAnd(local, val));
        }
        if (l.getDscps() != null && !l.getDscps().isEmpty()) {
            throw new BatfishException("detected dscps");
        }
        if (l.getDstPorts() != null) {
            BoolExpr val = computeValidRange(l.getDstPorts(), _symbolicPacket.getDstPort());
            val = l.getDstPorts().isEmpty() ? mkTrue() : val;
            local = (local == null ? val : mkAnd(local, val));
        }
        if (l.getSrcPorts() != null) {
            BoolExpr val = computeValidRange(l.getSrcPorts(), _symbolicPacket.getSrcPort());
            val = l.getSrcPorts().isEmpty() ? mkTrue() : val;
            local = (local == null ? val : mkAnd(local, val));
        }
        if (l.getEcns() != null && !l.getEcns().isEmpty()) {
            throw new BatfishException("detected ecns");
        }
        if (l.getTcpFlags() != null) {
            BoolExpr val = computeTcpFlags(l.getTcpFlags());
            val = l.getTcpFlags().isEmpty() ? mkTrue() : val;
            local = (local == null ? val : mkAnd(local, val));
        }
        if (l.getFragmentOffsets() != null && !l.getFragmentOffsets().isEmpty()) {
            throw new BatfishException("detected fragment offsets");
        }
        if (l.getIcmpCodes() != null) {
            BoolExpr val = computeValidRange(l.getIcmpCodes(), _symbolicPacket.getIcmpCode());
            val = l.getIcmpCodes().isEmpty() ? mkTrue() : val;
            local = (local == null ? val : mkAnd(local, val));
        }
        if (l.getIcmpTypes() != null) {
            BoolExpr val = computeValidRange(l.getIcmpTypes(), _symbolicPacket.getIcmpType());
            val = l.getIcmpTypes().isEmpty() ? mkTrue() : val;
            local = (local == null ? val : mkAnd(local, val));
        }
        if (l.getStates() != null && !l.getStates().isEmpty()) {
            throw new BatfishException("detected states");
        }
        if (l.getIpProtocols() != null) {
            BoolExpr val = computeIpProtocols(l.getIpProtocols());
            val = l.getIpProtocols().isEmpty() ? mkTrue() : val;
            local = (local == null ? val : mkAnd(local, val));
        }
        if (l.getNotDscps() != null && !l.getNotDscps().isEmpty()) {
            throw new BatfishException("detected NOT dscps");
        }
        if (l.getNotDstIps() != null && !l.getNotDstIps().isEmpty()) {
            throw new BatfishException("detected NOT dst ip");
        }
        if (l.getNotSrcIps() != null && !l.getNotSrcIps().isEmpty()) {
            throw new BatfishException("detected NOT src ip");
        }
        if (l.getNotDstPorts() != null && !l.getNotDstPorts().isEmpty()) {
            throw new BatfishException("detected NOT dst port");
        }
        if (l.getNotSrcPorts() != null && !l.getNotSrcPorts().isEmpty()) {
            throw new BatfishException("detected NOT src port");
        }
        if (l.getNotEcns() != null && !l.getNotEcns().isEmpty()) {
            throw new BatfishException("detected NOT ecns");
        }
        if (l.getNotIcmpCodes() != null && !l.getNotIcmpCodes().isEmpty()) {
            throw new BatfishException("detected NOT icmp codes");
        }
        if (l.getNotIcmpTypes() != null && !l.getNotIcmpTypes().isEmpty()) {
            throw new BatfishException("detected NOT icmp types");
        }
        if (l.getNotFragmentOffsets() != null && !l.getNotFragmentOffsets().isEmpty()) {
            throw new BatfishException("detected NOT fragment offset");
        }
        if (l.getNotIpProtocols() != null && !l.getNotIpProtocols().isEmpty()) {
            throw new BatfishException("detected NOT ip protocols");
        }
        if (local != null) {
            BoolExpr ret;
            if (l.getAction() == LineAction.ACCEPT) {
                ret = mkTrue();
            } else {
                ret = mkFalse();
            }
            if (l.getNegate()) {
                local = mkNot(local);
            }
            acc = mkIf(local, ret, acc);
        }
    }
    return acc;
}

Example 54 with BoolExpr

use of com.microsoft.z3.BoolExpr in project batfish by batfish.

the class EncoderSlice method addBestOverallConstraints.

/*
   * Constraints that specify that the best choice is
   * better than all alternatives, and is at least one of the choices:
   *
   * (1) if no options are valid, then best is not valid
   * (2) if some option is valid, then we have the following:
   *
   * (best <= best_prot1) and ... and (best <= best_protn)
   * (best =  best_prot1) or  ... or  (best =  best_protn)
   */
private void addBestOverallConstraints() {
    for (Entry<String, Configuration> entry : getGraph().getConfigurations().entrySet()) {
        String router = entry.getKey();
        Configuration conf = entry.getValue();
        // These constraints will be added at the protocol-level when a single protocol
        if (!_optimizations.getSliceHasSingleProtocol().contains(router)) {
            boolean someProto = false;
            BoolExpr acc = null;
            BoolExpr somePermitted = null;
            SymbolicRoute best = _symbolicDecisions.getBestNeighbor().get(router);
            for (Protocol proto : getProtocols().get(router)) {
                someProto = true;
                SymbolicRoute bestVars = _symbolicDecisions.getBestVars(_optimizations, router, proto);
                assert (bestVars != null);
                if (somePermitted == null) {
                    somePermitted = bestVars.getPermitted();
                } else {
                    somePermitted = mkOr(somePermitted, bestVars.getPermitted());
                }
                BoolExpr val = mkAnd(bestVars.getPermitted(), equal(conf, proto, best, bestVars, null, true));
                if (acc == null) {
                    acc = val;
                } else {
                    acc = mkOr(acc, val);
                }
                add(mkImplies(bestVars.getPermitted(), greaterOrEqual(conf, proto, best, bestVars, null)));
            }
            if (someProto) {
                if (acc != null) {
                    add(mkEq(somePermitted, best.getPermitted()));
                    add(mkImplies(somePermitted, acc));
                }
            } else {
                add(mkNot(best.getPermitted()));
            }
        }
    }
}

Example 55 with BoolExpr

use of com.microsoft.z3.BoolExpr in project batfish by batfish.

the class EncoderSlice method ipWildCardBound.

/*
   * Create a boolean expression for a variable being withing an IpWildCard bound
   */
private BoolExpr ipWildCardBound(BitVecExpr field, IpWildcard wc) {
    BitVecExpr ip = getCtx().mkBV(wc.getIp().asLong(), 32);
    BitVecExpr mask = getCtx().mkBV(~wc.getWildcard().asLong(), 32);
    return mkEq(getCtx().mkBVAND(field, mask), getCtx().mkBVAND(ip, mask));
}