WIP Packer

dns.packer.js

@@ -77,16 +77,6 @@ var dnspack = exports.DNS_PACKER = {
       total += 4; // two bytes type two bytes class
     }
 
-    function packRdata(a) {
-      dv.setUint16(total, 8, false);
-      total += 2;
-      dv.setUint32(total, 0xFFFFFFFF, false)
-      total += 4;
-      dv.setUint32(total, 0xFFFFFFFF, false)
-      total += 4;
-      //throw new Error('not implemented');
-    }
-
     function packAnswer(a) {
       packQuestion(a);
 
@@ -107,7 +97,7 @@ var dnspack = exports.DNS_PACKER = {
           total += 1;
         });
       } else {
-        packRdata(a);
+        dnspack.packRdata(ab, dv, total, a);
       }
     }
 
@@ -148,5 +138,6 @@ var dnspack = exports.DNS_PACKER = {
   }
 
 };
+dnspack.packRdata = exports.DNS_RDATA_PACK || require('./dns.rdata.pack.js').DNS_RDATA_PACK;
 
 }('undefined' !== typeof window ? window : exports));

dns.packer.type.a.js

@@ -0,0 +1,21 @@
+(function (exports) {
+'use strict';
+
+// An 'A' record is a 32-bit value representing the IP address
+
+exports.DNS_PACKER_TYPE_A = function (ab, dv, total, record) {
+  if (!record.address) {
+    throw new Error("no address on A record");
+  }
+
+  // i.e. 127.0.0.1 => 0x7F, 0x00, 0x00, 0x01
+  //record.rdlength = 4;
+  record.address.split('.').forEach(function (octet) {
+    dv.setUint8(total, parseInt(octet, 10), false);
+    total += 1;
+  });
+
+  return total;
+};
+
+}('undefined' !== typeof window ? window : exports));

dns.packer.type.aaaa.js

@@ -0,0 +1,34 @@
+(function (exports) {
+'use strict';
+
+// 'AAAA'
+// Value: IP Address
+// Meaning:Use: 16 octets (8 sexdectets, 128 bits) represting the IP address
+
+exports.DNS_PACKER_TYPE_AAAA = function (ab, dv, total, record) {
+  if (!record.address) {
+    throw new Error("no address on A record");
+  }
+
+  // i.e. ::1 => 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0001
+  // i.e. FFFF:DDDD::1 => 0xFFFF, 0xDDDD, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0001
+  //record.rdlength = 16;
+  var address = '0' + record.address; // prevent case of two leading blanks, such as '::1'
+  var parts = address.split(':');
+  parts.forEach(function (sedectet, i) {
+    if (!sedectet) {
+      parts[i] = '0';
+      while (parts.length < 8) {
+        parts.splice(i + 1, 0, '0');
+      }
+    }
+  });
+  parts.forEach(function (sedectet) {
+    dv.setUint16(total, parseInt(sedectet, 16), false);
+    total += 2;
+  });
+
+  return total;
+};
+
+}('undefined' !== typeof window ? window : exports));

dns.rdata.pack.js

@@ -0,0 +1,45 @@
+(function (exports) {
+'use strict';
+
+var classes = exports.DNS_CLASSES || require('./dns.classes.js').DNS_CLASSES;
+var types = exports.DNS_TYPES || require('./dns.types.js').DNS_TYPES;
+
+exports.DNS_RDATA_PACK = function (ab, dv, total, record) {
+  // ab is needed if the rdata makes use of compression pointers
+  // packet is given for convenience
+  var packer;
+  var className = classes[record.class];
+  var typeName = types[record.type];
+
+
+  if (!className) {
+    throw new Error("Support for DNS Class 0x" + record.class.toString(16) + " (" + record.class + ")"
+      + " is not implemented yet. Open an issue if you actually need support"
+      + " (i.e. you're not working with a malformed packet)"
+    );
+  }
+
+  if (!typeName) {
+    throw new Error("Support for DNS Type 0x" + record.type.toString(16) + " (" + record.type + ")"
+      + " is not implemented yet. Open an issue if you actually need support"
+      + " (i.e. you're not working with a malformed packet)"
+    );
+  }
+
+  try {
+    packer = exports['DNS_PACKER_TYPE_' + typeName]
+      || require('./dns.packer.type.' + typeName.toLowerCase())['DNS_PACKER_TYPE_' + typeName];
+  }
+  catch (e) { /*console.error(e)*/ }
+
+  if (!packer) {
+    throw new Error("Packer for DNS Type " + typeName + " could not be loaded."
+      + " Did you include <script src=\"dns.packer.type." + typeName.toLowerCase() + ".js\"></script> ?"
+      + " (or perhaps we plan to implement it and haven't yet - in which case please open an issue)"
+    );
+  }
+
+  return packer(ab, dv, total, record);
+};
+
+}('undefined' !== typeof window ? window : exports));

dns.rdata.parse.js

@@ -1,9 +1,6 @@
 (function (exports) {
 'use strict';
 
-var classes = exports.DNS_CLASSES || require('./dns.classes.js').DNS_CLASSES;
-var types = exports.DNS_TYPES || require('./dns.types.js').DNS_TYPES;
-
 exports.DNS_RDATA_PARSE = function (ab, packet, record) {
   // ab is needed if the rdata makes use of compression pointers
   // packet is given for convenience

test/packer.type.a.js

@@ -0,0 +1,30 @@
+'use strict';
+
+var packer = require('../dns.packer.type.a.js').DNS_PACKER_TYPE_A;
+var ab = new ArrayBuffer(4);
+var dv = new DataView(ab);
+var total;
+
+// just to see that bytes are changed as a marker
+dv.setUint32(0x0, 0xDDDDDDDD, false);
+
+[ '0.0.0.0'
+, '127.0.0.1'
+, '192.168.1.100'
+, '216.21.170.44'
+, '255.255.255.255'
+].forEach(function (ipv4) {
+  total = 0;
+  total = packer(ab, dv, total, { address: ipv4 });
+  if (0x04 !== total) {
+    console.error('unexpected total ' + total);
+    process.exit(1);
+  }
+  if (ipv4 !== new Uint8Array(ab).join('.')) {
+    console.error("expected: ", ipv4);
+    console.error("actual: ", new Uint8Array(ab).join('.'));
+    process.exit(1);
+  }
+});
+
+console.log('PASS');

test/packer.type.aaaa.js

@@ -0,0 +1,41 @@
+'use strict';
+
+var packer = require('../dns.packer.type.aaaa.js').DNS_PACKER_TYPE_AAAA;
+var ab = new ArrayBuffer(20);
+var dv = new DataView(ab);
+var total = 0;
+
+// just to see that bytes are changed as a marker
+dv.setUint16(0x0, 0xDDDD, false);
+dv.setUint16(0x2, 0xDDDD, false);
+dv.setUint16(0x4, 0xDDDD, false);
+dv.setUint16(0x6, 0xDDDD, false);
+dv.setUint16(0x8, 0xDDDD, false);
+dv.setUint16(0xA, 0xDDDD, false);
+dv.setUint16(0xC, 0xDDDD, false);
+dv.setUint16(0xE, 0xDDDD, false);
+dv.setUint16(0x10, 0xDDDD, false);
+dv.setUint16(0x12, 0xDDDD, false);
+
+[ [ '::1'
+  , [ 0xDD, 0xDD, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0xDD, 0xDD ].join(' ') ]
+, [ 'fe80::1'
+  , [ 0xDD, 0xDD, 0xFE, 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0xDD, 0xDD ].join(' ') ]
+, [ 'fd41:50ca:2169:f4e:5020:f756:ca4e:c3b5'
+  , [ 0xDD, 0xDD, 0xFD, 0x41, 0x50, 0xCA, 0x21, 0x69, 0x0F, 0x4E
+    , 0x50, 0x20, 0xF7, 0x56, 0xCA, 0x4E, 0xC3, 0xB5, 0xDD, 0xDD ].join(' ') ]
+].forEach(function (ipv6) {
+  total = 2; // leave leading 0x00
+  total = packer(ab, dv, total, { address: ipv6[0] });
+  if (0x12 !== total) {
+    console.error('unexpected total ' + total);
+    process.exit(1);
+  }
+  if (ipv6[1] !== new Uint8Array(ab).join(' ')) {
+    console.error("expected: ", ipv6[1]);
+    console.error("actual: ", new Uint8Array(ab).join(' '));
+    process.exit(1);
+  }
+});
+
+console.log('PASS');