net.dnsviz.lookingglass.DNSLookingGlass.java Source code

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Here is the source code for net.dnsviz.lookingglass.DNSLookingGlass.java

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/*
 * This file is a part of DNSViz, a tool suite for DNS/DNSSEC monitoring,
 * analysis, and visualization.
 * Created by Casey Deccio (casey@deccio.net)
 *
 * Copyright 2016 VeriSign, Inc.
 *
 * DNSViz is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * DNSViz is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with DNSViz.  If not, see <http://www.gnu.org/licenses/>.
 */

package net.dnsviz.lookingglass;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.net.InetAddress;
import java.net.UnknownHostException;

import org.json.JSONArray;
import org.json.JSONObject;
import org.json.JSONException;

import net.dnsviz.transport.DNSQueryTransportHandler;
import net.dnsviz.transport.DNSQueryTransportHandlerTCP;
import net.dnsviz.transport.DNSQueryTransportHandlerUDP;
import net.dnsviz.transport.DNSQueryTransportManager;
import net.dnsviz.util.Base64Decoder;
import net.dnsviz.util.Base64Encoder;
import net.dnsviz.websocket.WebSocketClient;

public class DNSLookingGlass {
    public DNSLookingGlass() {
    }

    protected DNSQueryTransportHandler[] getDNSQueryTransportHandlers(JSONObject obj)
            throws JSONException, UnknownHostException {
        DNSQueryTransportHandler[] ret;
        JSONArray requests;
        String[] vers;
        String src;
        int sport;
        JSONObject reqObj;

        vers = Double.toString(obj.getDouble("version")).split("\\.");
        if (Integer.parseInt(vers[0]) != 1 || Integer.parseInt(vers[1]) > 0) {
            throw new JSONException("Version of JSON input is invalid");
        }

        requests = obj.getJSONArray("requests");
        ret = new DNSQueryTransportHandler[requests.length()];
        for (int i = 0; i < requests.length(); i++) {
            reqObj = requests.getJSONObject(i);
            if (reqObj.has("src")) {
                src = reqObj.getString("src");
            } else {
                src = null;
            }
            if (reqObj.has("sport")) {
                sport = reqObj.getInt("sport");
            } else {
                sport = 0;
            }
            ret[i] = getDNSQueryTransportHandler(reqObj.getString("req"), reqObj.getString("dst"),
                    reqObj.getInt("dport"), src, sport, reqObj.getLong("timeout"), reqObj.getBoolean("tcp"));
        }
        return ret;
    }

    protected JSONObject getEncodedResponses(DNSQueryTransportHandler[] qths) {
        JSONObject ret;
        JSONObject response;

        JSONArray responses = new JSONArray();
        for (int i = 0; i < qths.length; i++) {
            response = new JSONObject();
            response.put("res", qths[i].getEncodedResponse());
            if (qths[i].getError() != null) {
                response.put("err", qths[i].getError());
                if (qths[i].getErrno() != null) {
                    response.put("errno", qths[i].getErrno());
                }
            }
            if (qths[i].getSource() != null) {
                response.put("src", qths[i].getSource().getHostAddress());
            } else {
                response.put("src", (String) null);
            }
            if (qths[i].getSPort() != 0) {
                response.put("sport", qths[i].getSPort());
            } else {
                response.put("sport", (String) null);
            }
            response.put("time_elapsed", qths[i].timeElapsed());
            responses.put(response);
        }

        ret = new JSONObject();
        ret.put("version", "1.0");
        ret.put("responses", responses);
        return ret;
    }

    public DNSQueryTransportHandler getDNSQueryTransportHandler(String req, String dst, int dport, String src,
            int sport, long timeout, boolean tcp) throws UnknownHostException {
        Base64Decoder d = new Base64Decoder();
        byte[] byteReq = d.decode(req.getBytes());
        InetAddress srcAddr = null;
        InetAddress dstAddr = null;
        if (dst != null) {
            dstAddr = InetAddress.getByName(dst);
        }
        if (src != null) {
            srcAddr = InetAddress.getByName(src);
        }
        if (tcp) {
            return new DNSQueryTransportHandlerTCP(byteReq, dstAddr, dport, srcAddr, sport, timeout);
        } else {
            return new DNSQueryTransportHandlerUDP(byteReq, dstAddr, dport, srcAddr, sport, timeout);
        }
    }

    public void executeQueries(DNSQueryTransportHandler[] qths) throws IOException {
        int i;
        DNSQueryTransportManager qtm = new DNSQueryTransportManager();
        qtm.query(qths);
        for (i = 0; i < qths.length; i++) {
            qths[i].finalize();
        }
    }

    protected void interact(WebSocketClient ws) throws IOException {
        byte[] input;
        while ((input = ws.read()).length > 0) {
            ws.write(run(new String(input)).getBytes());
        }
    }

    public String run(String json) {
        JSONObject ret;
        try {
            DNSQueryTransportHandler[] qths = getDNSQueryTransportHandlers(new JSONObject(json));
            executeQueries(qths);
            return getEncodedResponses(qths).toString();
        } catch (Exception ex) {
            ret = new JSONObject();
            ret.put("version", "1.0");
            ret.put("error", getErrorTrace(ex));
            return ret.toString();
        }
    }

    protected String getErrorTrace(Exception err) {
        StringWriter sw = new StringWriter();
        PrintWriter pw = new PrintWriter(sw);
        err.printStackTrace(pw);
        return sw.toString();
    }

    public static void main(String[] args) throws IOException {
        WebSocketClient ws = new WebSocketClient(args[0], Integer.parseInt(args[1]), args[2], args[3]);
        DNSLookingGlass lg = new DNSLookingGlass();
        lg.interact(ws);
    }
}