WIP add cp, add server

bin/debug.js

@@ -1,3 +1,8 @@
+#!/usr/bin/env node
+
+// node bin/debug.js ../dig.js/blar.DOEsNteXiST.AJ.OnEal.DAplIE.me.any.0.bin
+// node bin/debugd.js ../dig.js/blar.DOEsNteXiST.AJ.OnEal.DAplIE.me.any.0.bin
+// dig @localhost -p 65053 ANY DOEsNteXiST.AJ.OnEal.DAplIE.me
 (function () {
 'use strict';
 
@@ -17,6 +22,10 @@ console.log('//    HEADER    //');
 console.log('//////////////////');
 console.log('');
 
+console.log('');
+console.log('byte index 0x00');
+console.log('');
+
 console.log('id (int)', dv.getUint16(0));
 
 var flags = dv.getUint16(2, false);
@@ -45,9 +54,14 @@ console.log('ancount', ancount);
 console.log('nscount', nscount);
 console.log('arcount', arcount);
 
-function unpackQuestion(dv, total, len) {
+function unpackQuestionLabels(opts) {
+  var dv = opts.dv;
+  //var origTotal = opts.total;
+  var total = opts.total;
+  var len = opts.len;
   var qnames = [];
   var labelLen;
+
   while (true) {
     if (total >= len) {
       break;
@@ -58,29 +72,46 @@ function unpackQuestion(dv, total, len) {
       break;
     }
     if (192 === labelLen) {
-      console.log('ERROR: Compression pointer found');
+      var pointer = dv.getUint8(total, false);
-      console.log(dv.getUint8(total, false));
+      console.log('Found a pointer to'
-      console.log(dv.getUint8(dv.getUint8(total + 0, false), false));
+        + ' 0x' + pointer.toString(16) + ' (' + pointer + ')'
-      console.log(dv.getUint8(dv.getUint8(total + 1, false), false));
+        + ' at byte index'
-      console.log(dv.getUint8(dv.getUint8(total + 2, false), false));
+        + ' 0x' + leftPad(total.toString(16)) + ' (' + total + ')'
+        + ' which back-references:'
+      );
+      console.log('-4', dv.getUint8(pointer - 4, false));
+      console.log('-3', dv.getUint8(pointer - 3, false));
+      console.log('-2', dv.getUint8(pointer - 2, false));
+      console.log('-1', dv.getUint8(pointer - 1, false));
+      console.log(' 0', dv.getUint8(pointer + 0, false));
+      console.log('+1', dv.getUint8(pointer + 1, false));
+      console.log('+2', dv.getUint8(pointer + 2, false));
+      console.log('bytes near the pointer itself (not what it points to) are:');
+      console.log('-2', dv.getUint8(total - 2, false));
+      console.log('-1', dv.getUint8(total - 1, false));
+      console.log(' 0', dv.getUint8(total + 0, false));
+      console.log('+1', dv.getUint8(total + 1, false));
+      console.log('+2', dv.getUint8(total + 2, false));
+      console.log('+3', dv.getUint8(total + 3, false));
+      console.log('+4', dv.getUint8(total + 4, false));
+      //total += 1;
+      opts.cp = true;
+      qnames.push(unpackQuestionLabels({ dv: dv, total: pointer, len: len }).qname);
+      total += 1;
       break;
+    } else {
+      var i;
+      var label = '';
+      console.log('label len', labelLen);
+      for (i = 0; i < labelLen; i += 1) {
+        //console.log('total:', total, i);
+        label += String.fromCharCode(dv.getUint8(total + i, false));
+      }
+      total += label.length;
+      console.log('label:', label);
+      qnames.push(label);
     }
-    var i;
-    var label = '';
-    console.log('label len', labelLen);
-    for (i = 0; i < labelLen; i += 1) {
-      label += String.fromCharCode(dv.getUint8(total + i, false));
-    }
-    total += label.length;
-    console.log('label:', label);
-    qnames.push(label);
   }
-  // leading length and (potentially) trailing null
-  console.log('QNAME (len ' + (qnames.join('.').length + 1 + (labelLen ? 0 : 1)) + '):', qnames.join('.'));
-  console.log('QTYPE (len 2):', dv.getUint16(total, false));
-  total += 2;
-  console.log('QCLASS (len 2):', dv.getUint16(total, false));
-  total += 2;
 
   return {
     total: total
@@ -88,8 +119,23 @@ function unpackQuestion(dv, total, len) {
   };
 }
 
+function unpackQuestion(dv, total, len) {
+
+  var result = unpackQuestionLabels({ dv: dv, total: total, len: len });
+
+  // leading length and (potentially) trailing null
+  console.log('QNAME (len ' + (result.total - total) + '):', result.qname, result.cp ? '(pointer)' : '');
+  console.log('QTYPE (len 2):', dv.getUint16(result.total, false));
+  result.total += 2;
+  console.log('QCLASS (len 2):', dv.getUint16(result.total, false));
+  result.total += 2;
+
+  return result;
+}
+
 var q = { total: 12 };
 function mapChar(ch) { return JSON.stringify(String.fromCharCode(ch)) + '(' + ch + ')'; }
+function leftPad(ch) { ch = ch.toString(); while (ch.length < 2) { ch = '0' + ch; } return ch; }
 
 
 console.log('');
@@ -99,7 +145,7 @@ console.log('//////////////////');
 console.log('');
 for (count = 0; count < qdcount; count += 1) {
   console.log('');
-  console.log('Question ' + (count + 1) + ' of ' + qdcount + ' (byte index: ' + q.total + ')');
+  console.log('Question ' + (count + 1) + ' of ' + qdcount + ' (byte index: 0x' + leftPad(q.total.toString(16)) + ' ' + q.total + ')');
   q = unpackQuestion(dv, q.total, ab.byteLength);
   console.log('');
 }
@@ -111,7 +157,7 @@ console.log('//////////////////');
 console.log('');
 for (count = 0; count < ancount; count += 1) {
   console.log('');
-  console.log('Answer', count + 1, 'of', ancount + ' (byte index: ' + q.total + ')');
+  console.log('Answer', count + 1, 'of', ancount + ' (byte index: 0x' + q.total.toString(16) + ' ' + q.total + ')');
   q = unpackQuestion(dv, q.total, ab.byteLength);
   console.log('');
 }
@@ -124,7 +170,7 @@ console.log('//////////////////');
 console.log('');
 for (count = 0; count < nscount; count += 1) {
   console.log('');
-  console.log('Authority', count + 1, 'of', nscount + ' (byte index: ' + q.total + ')');
+  console.log('Authority', count + 1, 'of', nscount + ' (byte index: 0x' + q.total.toString(16) + ' ' + q.total + ')');
   q = unpackQuestion(dv, q.total, ab.byteLength);
   console.log('ttl (len 4):', dv.getUint32(q.total, false));
   q.total += 4;
@@ -144,10 +190,14 @@ console.log('//////////////////');
 console.log('');
 for (count = 0; count < arcount; count += 1) {
   console.log('');
-  console.log('Additional', count + 1, 'of', arcount + ' (byte index: ' + q.total + ')');
+  console.log('Additional', count + 1, 'of', arcount + ' (byte index: 0x' + q.total.toString(16) + ' ' + q.total + ')');
   q = unpackQuestion(dv, q.total, ab.byteLength);
   console.log('');
 }
 
+console.log('');
+console.log('total bytes', dv.byteLength);
+console.log('total bytes read', q.total);
+console.log('');
 
 }());

bin/debugd.js

@@ -0,0 +1,45 @@
+#!/usr/bin/env
+(function () {
+'use strict';
+
+var cli = { port: 65053, address: null, udp6: false, bin: process.argv[2] };
+var dgram = require('dgram');
+var server = dgram.createSocket({
+  type: cli.udp6 ? 'udp6' : 'udp4'
+, reuseAddr: true
+});
+var handlers = {};
+var bin = require('fs').readFileSync(cli.bin, null);
+
+handlers.onMessage = function (nb, rinfo) {
+  console.log('[DEBUG] got a message');
+
+  // replace the id to match
+  bin[0] = nb[0];
+  bin[1] = nb[1];
+  server.send(bin, rinfo.port, rinfo.address, function () {
+    console.log('[DEBUG] sent response');
+  });
+};
+
+handlers.onListening = function () {
+  /*jshint validthis:true*/
+  var server = this;
+
+  if (cli.mdns || '224.0.0.251' === cli.nameserver) {
+    server.setBroadcast(true);
+    server.addMembership(cli.nameserver);
+  }
+
+  console.log('');
+  console.log('Bound and Listening:');
+  console.log(server.address().address + '#' + server.address().port + ' (' + server.type + ')');
+};
+
+server.bind({
+  port: cli.port
+, address: cli.address
+});
+server.on('listening', handlers.onListening);
+
+}());