package org.freertr.rtr;

import java.util.List;
import java.util.Timer;
import java.util.TimerTask;
import org.freertr.addr.addrIP;
import org.freertr.addr.addrIPv4;
import org.freertr.auth.authLocal;
import org.freertr.cry.cryHashMd5;
import org.freertr.ip.ipFwdIface;
import org.freertr.ip.ipPrt;
import org.freertr.pack.packHolder;
import org.freertr.sec.secInfoCfg;
import org.freertr.sec.secInfoUtl;
import org.freertr.tab.tabAverage;
import org.freertr.tab.tabGen;
import org.freertr.user.userHelping;
import org.freertr.util.bits;
import org.freertr.util.cmds;
import org.freertr.util.counter;
import org.freertr.util.debugger;
import org.freertr.util.logger;
import org.freertr.util.state;

/**
 * ospfv2 interface
 *
 * @author matecsaba
 */
public class rtrOspf4iface implements Comparable<rtrOspf4iface>, ipPrt {

    /**
     * ipinfo config
     */
    public secInfoCfg ipInfoCfg;

    /**
     * list of neighbors
     */
    protected tabGen<rtrOspf4neigh> neighs;

    /**
     * the interface this works on
     */
    protected final ipFwdIface iface;

    /**
     * areas this interface belongs
     */
    protected tabGen<rtrOspf4area> areas = new tabGen<rtrOspf4area>();

    /**
     * counter
     */
    protected counter cntr;

    /**
     * interface type
     */
    public int networkType;

    private final rtrOspf4 lower;

    private Timer keepTimer;

    /**
     * suppress interface address
     */
    public boolean suppressAddr;

    /**
     * unsuppress interface address
     */
    public boolean unsuppressAddr;

    /**
     * check neighbor address is connected
     */
    public boolean connectedCheck;

    /**
     * passive interface
     */
    public boolean passiveInt;

    /**
     * ttl security
     */
    public int ttlSecurity;

    /**
     * hello timer
     */
    public int helloTimer;

    /**
     * dead timer
     */
    public int deadTimer;

    /**
     * retransmit timer
     */
    public int retransTimer;

    /**
     * dr priority
     */
    public int drPriority;

    /**
     * traffic eng suppression
     */
    public boolean teSuppress;

    /**
     * traffic eng metric
     */
    public int teMetric;

    /**
     * traffic eng bandwidth
     */
    public long teBandwidth;

    /**
     * traffic eng affinity
     */
    public int teAffinity;

    /**
     * traffic eng srlg
     */
    public int teSrlg;

    /**
     * segment rou index
     */
    public int srIndex;

    /**
     * bier index
     */
    public int brIndex;

    /**
     * bier index
     */
    public int brSub;

    /**
     * segment rou node
     */
    public boolean srNode;

    /**
     * segment rou pop
     */
    public boolean srPop;

    /**
     * echo interval
     */
    public int echoTimer;

    /**
     * echo parameters
     */
    public tabAverage echoParam;

    /**
     * dynamic metric
     */
    public int dynamicMetric;

    /**
     * dr address
     */
    public addrIPv4 drAddr = new addrIPv4();

    /**
     * bdr address
     */
    public addrIPv4 bdrAddr = new addrIPv4();

    /**
     * authentication password
     */
    public String authentication;

    /**
     * authentication mode: 1=cleartext, 2=md5
     */
    public int authenMode;

    /**
     * authentication id
     */
    public int authenKey;

    /**
     * interface metric
     */
    public int metric;

    /**
     * bfd enabled
     */
    public boolean bfdTrigger;

    /**
     * interface instance
     */
    public int instance;

    /**
     * point to point
     */
    public final static int netypP2p = 1;

    /**
     * point to multipoint
     */
    public final static int netypP2mp = 2;

    /**
     * point to multipoint, non broadcast
     */
    public final static int netypP2nb = 3;

    /**
     * broadcast
     */
    public final static int netypBrdct = 4;

    /**
     * non broadcast, multiple access
     */
    public final static int netypNbma = 5;

    /**
     * master/slave
     */
    public final static int dscrMstr = 0x01;

    /**
     * more descriptors
     */
    public final static int dscrMore = 0x02;

    /**
     * initialization
     */
    public final static int dscrInit = 0x04;

    /**
     * oob resyncronization
     */
    public final static int dscrRsyn = 0x08;

    /**
     * create one instance
     *
     * @param parent the ospf protocol
     * @param ara area where this interface belongs
     * @param ifc the ip interface to work on
     */
    public rtrOspf4iface(rtrOspf4 parent, rtrOspf4area ara, ipFwdIface ifc) {
        lower = parent;
        iface = ifc;
        areas.add(ara);
        networkType = netypP2p;
        setDefaultTimers();
        neighs = new tabGen<rtrOspf4neigh>();
        cntr = new counter();
        connectedCheck = true;
        drPriority = 0;
        authenMode = 1;
        metric = 10;
        teMetric = 10;
        ttlSecurity = -1;
        echoTimer = 60000;
        echoParam = new tabAverage(1, 65530);
        if (iface != null) {
            teBandwidth = iface.lower.getBandwidth();
        }
    }

    public int compareTo(rtrOspf4iface o) {
        if (iface.ifwNum < o.iface.ifwNum) {
            return -1;
        }
        if (iface.ifwNum > o.iface.ifwNum) {
            return +1;
        }
        return 0;
    }

    public String toString() {
        return "ospf on " + iface;
    }

    /**
     * get configuration
     *
     * @param l list to add
     * @param beg beginning
     * @param filter filter defaults
     */
    public void routerGetConfig(List<String> l, String beg, int filter) {
        l.add(cmds.tabulator + beg + "enable");
        String a = "";
        for (int i = 0; i < areas.size(); i++) {
            a = a + " " + areas.get(i).area;
        }
        l.add(cmds.tabulator + beg + "area" + a);
        cmds.cfgLine(l, !passiveInt, cmds.tabulator, beg + "passive", "");
        switch (networkType) {
            case netypP2p:
                a = "point2point";
                break;
            case netypP2mp:
                a = "point2multipoint";
                break;
            case netypP2nb:
                a = "point2nonbroadcast";
                break;
            case netypBrdct:
                a = "broadcast";
                break;
            case netypNbma:
                a = "nonbroadcast";
                break;
            default:
                a = "unknown=" + networkType;
                break;
        }
        l.add(cmds.tabulator + beg + "network " + a);
        cmds.cfgLine(l, !bfdTrigger, cmds.tabulator, beg + "bfd", "");
        cmds.cfgLine(l, !suppressAddr, cmds.tabulator, beg + "suppress-prefix", "");
        cmds.cfgLine(l, !unsuppressAddr, cmds.tabulator, beg + "unsuppress-prefix", "");
        cmds.cfgLine(l, !connectedCheck, cmds.tabulator, beg + "verify-source", "");
        cmds.cfgLine(l, authentication == null, cmds.tabulator, beg + "password", authLocal.passwdEncode(authentication, (filter & 2) != 0));
        switch (authenMode) {
            case 0:
                a = "null";
                break;
            case 1:
                a = "clear";
                break;
            case 2:
                a = "md5";
                break;
            default:
                a = "unknown=" + authenMode;
                break;
        }
        l.add(cmds.tabulator + beg + "authen-type " + a);
        l.add(cmds.tabulator + beg + "authen-id " + authenKey);
        l.add(cmds.tabulator + beg + "instance " + instance);
        l.add(cmds.tabulator + beg + "cost " + metric);
        l.add(cmds.tabulator + beg + "priority " + drPriority);
        l.add(cmds.tabulator + beg + "ttl-security " + ttlSecurity);
        l.add(cmds.tabulator + beg + "hello-time " + helloTimer);
        l.add(cmds.tabulator + beg + "dead-time " + deadTimer);
        l.add(cmds.tabulator + beg + "retransmit-time " + retransTimer);
        if (areas.get(0).traffEng) {
            a = beg + "traffeng ";
            cmds.cfgLine(l, !teSuppress, cmds.tabulator, a + "suppress", "");
            l.add(cmds.tabulator + a + "metric " + teMetric);
            l.add(cmds.tabulator + a + "bandwidth " + teBandwidth);
            l.add(cmds.tabulator + a + "affinity " + teAffinity);
            l.add(cmds.tabulator + a + "srlg " + teSrlg);
        }
        if (areas.get(0).segrouEna) {
            a = beg + "segrout ";
            cmds.cfgLine(l, srIndex < 1, cmds.tabulator, a + "index", "" + srIndex);
            cmds.cfgLine(l, !srNode, cmds.tabulator, a + "node", "");
            cmds.cfgLine(l, !srPop, cmds.tabulator, a + "pop", "");
        }
        if (areas.get(0).bierEna) {
            a = beg + "bier ";
            cmds.cfgLine(l, brIndex < 1, cmds.tabulator, a + "index", "" + brIndex);
            cmds.cfgLine(l, brSub < 1, cmds.tabulator, a + "subdomain", "" + brSub);
        }
        secInfoUtl.getConfig(l, ipInfoCfg, cmds.tabulator + beg + "ipinfo ");
        switch (dynamicMetric) {
            case 0:
                a = "disabled";
                break;
            case 1:
                a = "icmpecho";
                break;
            case 2:
                a = "udpecho";
                break;
            case 3:
                a = "twamp";
                break;
            default:
                a = "unknown=" + dynamicMetric;
        }
        cmds.cfgLine(l, dynamicMetric < 1, cmds.tabulator, beg + "dynamic-metric mode", a);
        l.add(cmds.tabulator + beg + "dynamic-metric time " + echoTimer);
        echoParam.getConfig(l, beg);
        for (int i = 0; i < neighs.size(); i++) {
            rtrOspf4neigh ntry = neighs.get(i);
            if (!ntry.statNeigh) {
                continue;
            }
            l.add(cmds.tabulator + beg + "neighbor " + ntry.peer);
        }
    }

    /**
     * schedule work
     *
     * @param wrk work
     */
    protected void schedWork(int wrk) {
        for (int i = 0; i < areas.size(); i++) {
            rtrOspf4area ara = areas.get(i);
            if (ara == null) {
                continue;
            }
            ara.schedWork(wrk);
        }
    }

    /**
     * do configuration
     *
     * @param a command
     * @param cmd parameters
     */
    public void routerDoConfig(String a, cmds cmd) {
        if (a.equals("network")) {
            int i = -1;
            a = cmd.word();
            if (a.equals("point2point")) {
                i = netypP2p;
            }
            if (a.equals("point2multipoint")) {
                i = netypP2mp;
            }
            if (a.equals("point2nonbroadcast")) {
                i = netypP2nb;
            }
            if (a.equals("broadcast")) {
                i = netypBrdct;
            }
            if (a.equals("nonbroadcast")) {
                i = netypNbma;
            }
            if (i < 0) {
                return;
            }
            networkType = i;
            setDefaultTimers();
            schedWork(3);
            return;
        }
        if (a.equals("area")) {
            tabGen<rtrOspf4area> lst = new tabGen<rtrOspf4area>();
            for (;;) {
                a = cmd.word();
                if (a.length() < 1) {
                    break;
                }
                rtrOspf4area ar = new rtrOspf4area(lower, bits.str2num(a));
                ar = lower.areas.find(ar);
                if (ar == null) {
                    continue;
                }
                lst.add(ar);
            }
            if (lst.size() < 1) {
                return;
            }
            schedWork(7);
            areas = lst;
            schedWork(7);
            return;
        }
        if (a.equals("neighbor")) {
            addrIPv4 adr = new addrIPv4();
            if (adr.fromString(cmd.word())) {
                return;
            }
            rtrOspf4neigh nei = new rtrOspf4neigh(lower, areas.get(0), this, adr);
            rtrOspf4neigh old = neighs.add(nei);
            if (old != null) {
                nei = old;
            } else {
                nei.startNow();
            }
            nei.statNeigh = true;
            return;
        }
        if (a.equals("passive")) {
            passiveInt = true;
            return;
        }
        if (a.equals("bfd")) {
            bfdTrigger = true;
            return;
        }
        if (a.equals("suppress-prefix")) {
            suppressAddr = true;
            schedWork(1);
            return;
        }
        if (a.equals("unsuppress-prefix")) {
            unsuppressAddr = true;
            schedWork(1);
            return;
        }
        if (a.equals("verify-source")) {
            connectedCheck = true;
            return;
        }
        if (a.equals("ttl-security")) {
            ttlSecurity = bits.str2num(cmd.word());
            return;
        }
        if (a.equals("hello-time")) {
            helloTimer = bits.str2num(cmd.word());
            restartTimer(false);
            return;
        }
        if (a.equals("dead-time")) {
            deadTimer = bits.str2num(cmd.word());
            return;
        }
        if (a.equals("retransmit-time")) {
            retransTimer = bits.str2num(cmd.word());
            return;
        }
        if (a.equals("priority")) {
            drPriority = bits.str2num(cmd.word());
            return;
        }
        if (a.equals("cost")) {
            metric = bits.str2num(cmd.word());
            schedWork(3);
            return;
        }
        if (a.equals("instance")) {
            instance = bits.str2num(cmd.word());
            return;
        }
        if (a.equals("password")) {
            authentication = authLocal.passwdDecode(cmd.word());
            return;
        }
        if (a.equals("authen-id")) {
            authenKey = bits.str2num(cmd.word());
            return;
        }
        if (a.equals("authen-type")) {
            authenMode = 0;
            a = cmd.word();
            if (a.equals("null")) {
                authenMode = 0;
                return;
            }
            if (a.equals("clear")) {
                authenMode = 1;
                return;
            }
            if (a.equals("md5")) {
                authenMode = 2;
                return;
            }
            return;
        }
        if (a.equals("traffeng")) {
            a = cmd.word();
            if (a.equals("suppress")) {
                teSuppress = true;
                schedWork(1);
                return;
            }
            if (a.equals("metric")) {
                teMetric = bits.str2num(cmd.word());
                schedWork(1);
                return;
            }
            if (a.equals("bandwidth")) {
                teBandwidth = bits.str2long(cmd.word());
                schedWork(1);
                return;
            }
            if (a.equals("affinity")) {
                teAffinity = bits.str2num(cmd.word());
                schedWork(1);
                return;
            }
            if (a.equals("srlg")) {
                teSrlg = bits.str2num(cmd.word());
                schedWork(1);
                return;
            }
            cmd.badCmd();
            return;
        }
        if (a.equals("segrout")) {
            a = cmd.word();
            if (a.equals("index")) {
                srIndex = bits.str2num(cmd.word());
                schedWork(3);
                return;
            }
            if (a.equals("node")) {
                srNode = true;
                schedWork(3);
                return;
            }
            if (a.equals("pop")) {
                srPop = true;
                schedWork(3);
                return;
            }
            cmd.badCmd();
            return;
        }
        if (a.equals("bier")) {
            a = cmd.word();
            if (a.equals("index")) {
                brIndex = bits.str2num(cmd.word());
                schedWork(3);
                return;
            }
            if (a.equals("subdomain")) {
                brSub = bits.str2num(cmd.word());
                schedWork(3);
                return;
            }
            cmd.badCmd();
            return;
        }
        if (a.equals("ipinfo")) {
            ipInfoCfg = secInfoUtl.doCfgStr(ipInfoCfg, cmd, false);
            return;
        }
        if (a.equals("dynamic-metric")) {
            a = cmd.word();
            if (a.equals("mode")) {
                a = cmd.word();
                dynamicMetric = 0;
                if (a.equals("disabled")) {
                    dynamicMetric = 0;
                }
                if (a.equals("icmpecho")) {
                    dynamicMetric = 1;
                }
                if (a.equals("udpecho")) {
                    dynamicMetric = 2;
                }
                if (a.equals("twamp")) {
                    dynamicMetric = 3;
                }
                schedWork(3);
                return;
            }
            if (a.equals("time")) {
                echoTimer = bits.str2num(cmd.word());
                return;
            }
            if (echoParam.doConfig(a, cmd)) {
                return;
            }
            if (a.equals("algo")) {
                echoParam.string2algo(cmd.word());
                schedWork(3);
                return;
            }
            cmd.badCmd();
            return;
        }
        cmd.badCmd();
    }

    /**
     * undo configuration
     *
     * @param a command
     * @param cmd parameters
     */
    public void routerUnConfig(String a, cmds cmd) {
        if (a.equals("neighbor")) {
            addrIPv4 adr = new addrIPv4();
            if (adr.fromString(cmd.word())) {
                return;
            }
            rtrOspf4neigh nei = new rtrOspf4neigh(lower, areas.get(0), this, adr);
            nei = neighs.find(nei);
            if (nei == null) {
                return;
            }
            nei.statNeigh = false;
            return;
        }
        if (a.equals("cost")) {
            metric = 10;
            schedWork(3);
            return;
        }
        if (a.equals("passive")) {
            passiveInt = false;
            return;
        }
        if (a.equals("ttl-security")) {
            ttlSecurity = -1;
            return;
        }
        if (a.equals("bfd")) {
            bfdTrigger = false;
            return;
        }
        if (a.equals("suppress-prefix")) {
            suppressAddr = false;
            schedWork(1);
            return;
        }
        if (a.equals("unsuppress-prefix")) {
            unsuppressAddr = false;
            schedWork(1);
            return;
        }
        if (a.equals("verify-source")) {
            connectedCheck = false;
            return;
        }
        if (a.equals("authen-id")) {
            authenKey = 0;
            return;
        }
        if (a.equals("authen-type")) {
            authenMode = 1;
            return;
        }
        if (a.equals("password")) {
            authentication = null;
            return;
        }
        if (a.equals("traffeng")) {
            a = cmd.word();
            if (a.equals("suppress")) {
                teSuppress = false;
                schedWork(1);
                return;
            }
            cmd.badCmd();
            return;
        }
        if (a.equals("segrout")) {
            a = cmd.word();
            if (a.equals("index")) {
                srIndex = 0;
                schedWork(3);
                return;
            }
            if (a.equals("node")) {
                srNode = false;
                schedWork(3);
                return;
            }
            if (a.equals("pop")) {
                srPop = false;
                schedWork(3);
                return;
            }
            cmd.badCmd();
            return;
        }
        if (a.equals("bier")) {
            a = cmd.word();
            if (a.equals("index")) {
                brIndex = 0;
                schedWork(3);
                return;
            }
            if (a.equals("subdomain")) {
                brSub = 0;
                schedWork(3);
                return;
            }
            cmd.badCmd();
            return;
        }
        if (a.equals("ipinfo")) {
            ipInfoCfg = secInfoUtl.doCfgStr(ipInfoCfg, cmd, true);
            return;
        }
        if (a.equals("dynamic-metric")) {
            a = cmd.word();
            if (a.equals("mode")) {
                dynamicMetric = 0;
                schedWork(3);
                return;
            }
            cmd.badCmd();
            return;
        }
        cmd.badCmd();
    }

    /**
     * get help text
     *
     * @param l list to update
     */
    public static void routerGetHelp(userHelping l) {
        l.add(null, "4 .         enable                  enable protocol processing");
        l.add(null, "4 5         area                    specify area number");
        l.add(null, "5 6,.         <num>                 area number");
        l.add(null, "6 6,.           <num>               secondary area number");
        l.add(null, "4 5         network                 specify network type");
        l.add(null, "5 .           point2point           point to point");
        l.add(null, "5 .           point2multipoint      point to multipoint");
        l.add(null, "5 .           point2nonbroadcast    point to multipoint, non broadcast");
        l.add(null, "5 .           broadcast             broadcast");
        l.add(null, "5 .           nonbroadcast          non broadcast, multiple access");
        l.add(null, "4 .         passive                 do not process packets");
        l.add(null, "4 .         bfd                     enable bfd triggered down");
        l.add(null, "4 .         suppress-prefix         do not advertise interface");
        l.add(null, "4 .         unsuppress-prefix       do advertise interface");
        l.add(null, "4 .         verify-source           check source address of updates");
        l.add(null, "4 5         instance                interface instance");
        l.add(null, "5 .           <num>                 instance");
        l.add(null, "4 5         cost                    interface cost");
        l.add(null, "5 .           <num>                 cost");
        l.add(null, "4 5         priority                router priority");
        l.add(null, "5 .           <num>                 priority 0=disable");
        l.add(null, "4 5         ttl-security            sending ttl value");
        l.add(null, "5 .           <num>                 ttl value");
        l.add(null, "4 5         hello-time              time between hellos");
        l.add(null, "5 .           <num>                 time in ms");
        l.add(null, "4 5         dead-time               time before neighbor down");
        l.add(null, "5 .           <num>                 time in ms");
        l.add(null, "4 5         retransmit-time         time before retarnsmitting");
        l.add(null, "5 .           <num>                 time in ms");
        l.add(null, "4 5         neighbor                specify static neighbor");
        l.add(null, "5 .           <addr>                address of peer interface");
        l.add(null, "4 5         password                password for authentication");
        l.add(null, "5 .           <text>                set password");
        l.add(null, "4 5         authen-type             mode for authentication");
        l.add(null, "5 .           null                  use nothing");
        l.add(null, "5 .           clear                 use cleartext");
        l.add(null, "5 .           md5                   use md5");
        l.add(null, "4 5         authen-id               id for authentication");
        l.add(null, "5 .           <num>                 key id");
        l.add(null, "4 5         traffeng                traffic engineering parameters");
        l.add(null, "5 .           suppress              do not advertise interface");
        l.add(null, "5 6           metric                set metric");
        l.add(null, "6 .             <num>               cost");
        l.add(null, "5 6           bandwidth             set bandwidth");
        l.add(null, "6 .             <num>               bandwidth");
        l.add(null, "5 6           affinity              set affinity");
        l.add(null, "6 .             <num>               affinity");
        l.add(null, "5 6           srlg                  set srlg");
        l.add(null, "6 .             <num>               affinity");
        l.add(null, "4 5         segrout                 segment routing parameters");
        l.add(null, "5 6           index                 set index");
        l.add(null, "6 .             <num>               index");
        l.add(null, "5 .           node                  set node flag");
        l.add(null, "5 .           pop                   request php");
        l.add(null, "4 5         bier                    bier parameters");
        l.add(null, "5 6           index                 set index");
        l.add(null, "6 .             <num>               index");
        l.add(null, "5 6           subdomain             set subdomain");
        l.add(null, "6 .             <num>               index");
        secInfoUtl.getHelp(l, 4, "ipinfo            check peers");
        l.add(null, "4 5         dynamic-metric            dynamic peer metric");
        l.add(null, "5 6           mode                    dynamic peer metric");
        l.add(null, "6 .             disabled              forbid echo requests");
        l.add(null, "6 .             icmpecho              icmp echo requests");
        l.add(null, "6 .             udpecho               udp echo requests");
        l.add(null, "6 .             twamp                 twamp echo requests");
        tabAverage.getHelp(l);
    }

    /**
     * close all neighbors
     *
     * @param shutdown complete shutdown
     */
    protected void closeNeighbors(boolean shutdown) {
        for (int i = neighs.size(); i >= 0; i--) {
            rtrOspf4neigh ntry = neighs.get(i);
            if (ntry == null) {
                continue;
            }
            ntry.statNeigh &= !shutdown;
            ntry.stopNow();
        }
        schedWork(7);
    }

    /**
     * setup timer thread
     *
     * @param shutdown set true to shut down
     */
    public void restartTimer(boolean shutdown) {
        try {
            keepTimer.cancel();
        } catch (Exception e) {
        }
        keepTimer = null;
        if (shutdown) {
            return;
        }
        keepTimer = new Timer();
        rtrOspf4ifaceHello task = new rtrOspf4ifaceHello(this);
        keepTimer.schedule(task, 500, helloTimer);
    }

    /**
     * set default timers
     */
    public void setDefaultTimers() {
        switch (networkType) {
            case netypP2p:
            case netypBrdct:
                helloTimer = 10000;
                break;
            case netypP2mp:
            case netypP2nb:
            case netypNbma:
                helloTimer = 30000;
                break;
        }
        deadTimer = helloTimer * 4;
        retransTimer = 3000;
    }

    /**
     * check if i've to peer with
     *
     * @param peer pere to check
     * @return true if yes, false if not
     */
    protected boolean shouldIpeer(addrIPv4 peer) {
        switch (networkType) {
            case netypP2p:
            case netypP2mp:
            case netypP2nb:
                return true;
            case netypBrdct:
            case netypNbma:
                break;
            default:
                return false;
        }
        if (amIdr()) {
            return true;
        }
        if (drAddr.compareTo(peer) == 0) {
            return true;
        }
        if (bdrAddr.compareTo(peer) == 0) {
            return true;
        }
        return false;
    }

    private addrIPv4 findDR(boolean drNeeded) {
        rtrOspf4neigh dr = new rtrOspf4neigh(lower, areas.get(0), this, iface.addr.toIPv4());
        dr.rtrPri = drPriority;
        dr.rtrID = lower.routerID.copyBytes();
        for (int i = 0; i < neighs.size(); i++) {
            rtrOspf4neigh ntry = neighs.get(i);
            if (ntry == null) {
                continue;
            }
            if (drNeeded) {
                if (ntry.peerDR.compareTo(ntry.peer) != 0) {
                    continue;
                }
            } else {
                if (ntry.peer.compareTo(drAddr) == 0) {
                    continue;
                }
                if (ntry.peerBDR.compareTo(ntry.peer) != 0) {
                    continue;
                }
            }
            if (dr.otherBetterDR(ntry)) {
                dr = ntry;
            }
        }
        if (dr.rtrPri < 1) {
            return new addrIPv4();
        }
        return dr.peer.copyBytes();
    }

    /**
     * check if need dr
     *
     * @return true if yes, false if no
     */
    protected boolean needDR() {
        switch (networkType) {
            case netypBrdct:
            case netypNbma:
                return true;
            default:
                return false;
        }
    }

    /**
     * elect drs for this interface
     */
    protected void electDRs() {
        if (!needDR()) {
            return;
        }
        addrIPv4 old = drAddr.copyBytes();
        drAddr = findDR(true);
        bdrAddr = findDR(false);
        if (old.compareTo(drAddr) == 0) {
            return;
        }
        if (debugger.rtrOspf4evnt) {
            logger.debug("dr change, dr=" + drAddr + " bdr=" + bdrAddr);
        }
        schedWork(7);
    }

    /**
     * check if i'm dr on the net
     *
     * @return true means yes, false means no
     */
    protected boolean amIdr() {
        if (!needDR()) {
            return false;
        }
        if (drAddr.compareTo(iface.addr.toIPv4()) == 0) {
            return true;
        }
        if (bdrAddr.compareTo(iface.addr.toIPv4()) == 0) {
            return true;
        }
        return false;
    }

    /**
     * need to advertise address
     *
     * @return true if yes, false if not
     */
    protected boolean needAdr() {
        switch (networkType) {
            case netypP2nb:
            case netypP2mp:
                return true;
            default:
                return false;
        }
    }

    /**
     * get authentication data
     *
     * @param rx true if received, false if sending
     * @return bytes in header
     */
    protected byte[] getAuthData1(boolean rx) {
        final int len = 8;
        byte[] buf = new byte[2 + len];
        bits.byteFill(buf, 0, buf.length, 0);
        buf[0] = (byte) instance;
        switch (authenMode) {
            case 0: // null
                return buf;
            case 1: // text
                if (authentication == null) {
                    return buf;
                }
                buf[1] = 1;
                byte[] pwd = authentication.getBytes();
                int i = pwd.length;
                if (i > len) {
                    i = len;
                }
                bits.byteCopy(pwd, 0, buf, 2, i);
                return buf;
            case 2: // md5
                if (authentication == null) {
                    return buf;
                }
                buf[1] = 2;
                buf[4] = (byte) authenKey;
                buf[5] = 16; // length
                bits.msbPutD(buf, 6, (int) bits.getTime());
                if (!rx) {
                    return buf;
                }
                byte[] buf2 = new byte[buf.length - 4];
                bits.byteCopy(buf, 0, buf2, 0, buf2.length);
                return buf2;
            default:
                return buf;
        }
    }

    /**
     * get authentication data
     *
     * @param pck packet to check
     * @return bytes in header
     */
    protected byte[] getAuthData2(packHolder pck) {
        if (authenMode != 2) {
            return new byte[0];
        }
        if (authentication == null) {
            return new byte[0];
        }
        cryHashMd5 h = new cryHashMd5();
        h.init();
        pck.hashData(h, 0, pck.dataSize());
        byte[] buf = authentication.getBytes();
        h.update(buf);
        for (int i = buf.length; i < 16; i++) {
            h.update(0);
        }
        return h.finish();
    }

    /**
     * unregister from ip
     */
    public void unregister2ip() {
        lower.fwdCore.protoDel(this, iface, null);
    }

    /**
     * register to ip
     */
    public void register2ip() {
        lower.fwdCore.protoAdd(this, iface, null);
    }

    /**
     * make packet header
     *
     * @param pck packet to update
     * @param area area
     * @param typ type of packet
     */
    protected void mkPackHead(packHolder pck, rtrOspf4area area, int typ) {
        pck.merge2beg();
        if (debugger.rtrOspf4traf) {
            logger.debug("sending " + rtrOspf4neigh.msgTyp2string(typ) + " on " + iface);
        }
        pck.putByte(0, rtrOspf4.verNum); // version
        pck.putByte(1, typ); // message type
        pck.msbPutW(2, pck.dataSize() + rtrOspf4.sizeHead); // size
        pck.putAddr(4, lower.routerID); // router id
        pck.msbPutD(8, area.area); // area id
        pck.msbPutW(12, 0); // checksum
        byte[] buf = getAuthData1(false);
        pck.putCopy(buf, 0, 14, buf.length);
        int i = pck.putIPsum(0, rtrOspf4.sizeHead - 8, 0);
        i = pck.getIPsum(0, pck.dataSize(), i);
        buf = getAuthData2(pck);
        if (buf.length < 1) {
            pck.lsbPutW(12, 0xffff - i); // checksum
        }
        pck.putSkip(rtrOspf4.sizeHead);
        pck.merge2beg();
        buf = getAuthData2(pck);
        pck.putCopy(buf, 0, 0, buf.length);
        pck.putSkip(buf.length);
        pck.merge2end();
    }

    /**
     * make hello packet
     *
     * @param pck packet to update
     * @param area area
     */
    protected void mkHelloPack(packHolder pck, rtrOspf4area area) {
        pck.merge2beg();
        addrIPv4 adr = iface.network.mask.toIPv4();
        pck.putAddr(0, adr); // netmask
        pck.msbPutW(4, helloTimer / 1000); // hello interval
        pck.putByte(6, area.getCapabilities()); // optional capabilities
        pck.putByte(7, drPriority); // dr priority
        pck.msbPutD(8, deadTimer / 1000); // dead interval
        pck.putAddr(12, drAddr); // designated router address
        pck.putAddr(16, bdrAddr); // backup designated router address
        pck.putSkip(20);
        for (int i = 0; i < neighs.size(); i++) {
            rtrOspf4neigh ntry = neighs.get(i);
            if (ntry == null) {
                continue;
            }
            if (ntry.area.area != area.area) {
                continue;
            }
            if (ntry.rtrID.isEmpty()) {
                continue;
            }
            pck.putAddr(0, ntry.rtrID);
            pck.putSkip(addrIPv4.size);
        }
    }

    /**
     * make database descriptor packet
     *
     * @param pck packet to update
     * @param area area
     * @param flags descriptor flags
     * @param seq sequence number
     */
    protected void mkDescrPack(packHolder pck, rtrOspf4area area, int flags, int seq) {
        pck.merge2beg();
        pck.msbPutW(0, iface.lower.getMTUsize()); // interface mtu
        pck.putByte(2, area.getCapabilities()); // optional capabilities
        pck.putByte(3, flags); // db flags
        pck.msbPutD(4, seq); // sequence number
        pck.putSkip(8);
    }

    /**
     * make link state update packet
     *
     * @param pck packet to update
     * @param lsa lsa to put
     */
    protected void mkLSupdate(packHolder pck, rtrOspf4lsa lsa) {
        pck.msbPutD(0, 1);
        pck.putSkip(4);
        int i = lsa.writeData(pck, 0, true);
        pck.putSkip(i);
    }

    /**
     * send one packet on this interface
     *
     * @param pck packet to send
     * @param area area
     * @param justDR send just to dr
     * @param typ type of packet
     */
    protected void packSend(packHolder pck, rtrOspf4area area, boolean justDR, int typ) {
        pck.IPdf = false;
        pck.IPfrg = 0;
        pck.IPalrt = -1;
        pck.IPttl = ttlSecurity;
        pck.IPtos = 0;
        pck.IPid = 0;
        pck.IPprt = rtrOspf4.protoNum;
        pck.IPsrc.setAddr(iface.addr);
        if (justDR) {
            pck.IPtrg.fromString("224.0.0.6");
        } else {
            pck.IPtrg.fromString("224.0.0.5");
        }
        mkPackHead(pck, area, typ);
        lower.fwdCore.protoPack(iface, null, pck);
    }

    /**
     * send hello packet
     *
     * @param area area
     */
    protected void sendHello(rtrOspf4area area) {
        if (passiveInt) {
            return;
        }
        packHolder pck = new packHolder(true, true);
        mkHelloPack(pck, area);
        switch (networkType) {
            case netypP2mp:
            case netypP2p:
            case netypBrdct:
                packSend(pck, area, false, rtrOspf4neigh.msgTypHello);
                return;
            case netypNbma:
            case netypP2nb:
                break;
            default:
                return;
        }
        for (int i = 0; i < neighs.size(); i++) {
            rtrOspf4neigh ntry = neighs.get(i);
            if (ntry == null) {
                continue;
            }
            if (ntry.area.area != area.area) {
                continue;
            }
            ntry.packSend(pck.copyBytes(true, true), rtrOspf4neigh.msgTypHello);
        }
    }

    /**
     * get protocol number
     *
     * @return number
     */
    public int getProtoNum() {
        return rtrOspf4.protoNum;
    }

    /**
     * get counter
     *
     * @return counter
     */
    public counter getCounter() {
        return cntr;
    }

    /**
     * close interface
     *
     * @param iface interface
     */
    public void closeUp(ipFwdIface iface) {
        restartTimer(true);
        unregister2ip();
        closeNeighbors(true);
    }

    /**
     * set state
     *
     * @param iface interface
     * @param stat state
     */
    public void setState(ipFwdIface iface, state.states stat) {
        if (stat == state.states.up) {
            return;
        }
        closeNeighbors(false);
    }

    /**
     * received packet
     *
     * @param iface interface
     * @param pck packet
     */
    public void recvPack(ipFwdIface iface, packHolder pck) {
        cntr.rx(pck);
        if (passiveInt) {
            cntr.drop(pck, counter.reasons.notUp);
            return;
        }
        if ((connectedCheck) && (!iface.network.matches(pck.IPsrc))) {
            logger.info("got from out of subnet peer " + pck.IPsrc);
            cntr.drop(pck, counter.reasons.badAddr);
            return;
        }
        rtrOspf4area ara = new rtrOspf4area(lower, pck.msbGetD(8));
        ara = areas.find(ara);
        if (ara == null) {
            logger.info("got invalid area from " + pck.IPsrc);
            iface.cntr.drop(pck, counter.reasons.badID);
            return;
        }
        rtrOspf4neigh nei = new rtrOspf4neigh(lower, ara, this, pck.IPsrc.toIPv4());
        rtrOspf4neigh old = neighs.add(nei);
        boolean sndHll = false;
        if (old != null) {
            nei = old;
        } else {
            nei.startNow();
            sndHll = true;
        }
        try {
            nei.recvPack(pck);
            if (sndHll) {
                sendHello(ara);
            }
        } catch (Exception e) {
            logger.traceback(e);
        }
    }

    /**
     * alert packet
     *
     * @param rxIfc interface
     * @param pck packet
     * @return false if success, true if error
     */
    public boolean alertPack(ipFwdIface rxIfc, packHolder pck) {
        return true;
    }

    /**
     * error packet
     *
     * @param err error code
     * @param rtr address
     * @param rxIfc interface
     * @param pck packet
     */
    public void errorPack(counter.reasons err, addrIP rtr, ipFwdIface rxIfc, packHolder pck) {
    }

}

class rtrOspf4ifaceHello extends TimerTask {

    private final rtrOspf4iface lower;

    public rtrOspf4ifaceHello(rtrOspf4iface parent) {
        lower = parent;
    }

    public void run() {
        try {
            lower.electDRs();
            for (int i = 0; i < lower.areas.size(); i++) {
                rtrOspf4area area = lower.areas.get(i);
                if (area == null) {
                    continue;
                }
                lower.sendHello(area);
            }
        } catch (Exception e) {
            logger.traceback(e);
        }
    }

}