coolaj86/dns-suite.js
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bugfix: add null terminators for packing SOA records

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This commit is contained in:
AJ ONeal 2017-09-28 13:13:18 -06:00
parent 98187043ec
commit a538fa4f58
4 changed files with 60 additions and 27 deletions
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30
bin/dns-test.js
View File

@ -35,7 +35,7 @@ var hexdump = require('hexdump.js').hexdump;
function testJsonAsync(nb) {
var packet = dnsjs.write(JSON.parse(nb.toString('ascii')));
var str = hexdump(packet);
console.log(str);
console.info(str);
var json = dnsjs.parse(packet);
if (json.error) {
console.error(json);
@ -43,7 +43,7 @@ function testJsonAsync(nb) {
return;
}
console.log("[OK] JSON -> binary -> JSON");
console.info("[OK] JSON -> binary -> JSON");
if (!outname) {
console.warn('');
@ -54,7 +54,7 @@ function testJsonAsync(nb) {
return;
}
fs.writeFileSync(path.basename(filename).replace(path.extname(filename), '.bin'), packet, null);
fs.writeFileSync(outname, packet, null);
}
function testBinAsync(nb) {
@ -66,6 +66,8 @@ function testBinAsync(nb) {
return;
}
var bin2 = dnsjs.write(json);
//var debugname = outname || path.basename(filename);
//fs.writeFileSync(debugname.replace(path.extname(debugname), '.bin'), bin2, null);
var json2 = dnsjs.parse(bin2);
if (json2.error) {
console.error(json2);
@ -86,12 +88,22 @@ function testBinAsync(nb) {
.replace(/,"cpcount":\d+/, '')
);
//json2 = JSON.parse(JSON.stringify(json2));
//console.log(json);
//console.log(json2);
assert.deepEqual(json, json2);
try {
assert.deepEqual(json, json2);
} catch(e) {
console.error('');
console.error('Original');
console.error(JSON.stringify(json, null, 2));
console.error('');
console.error('Converted');
console.error(JSON.stringify(json2, null, 2));
console.error('');
process.exit(422);
return;
}
console.log("[OK] binary -> JSON -> binary -> JSON");
console.log("(compression pointer support needs to be improved in order to support direct bin -> JSON -> bin testing)");
console.info("[OK] binary -> JSON -> binary -> JSON");
console.warn("(compression pointer support needs to be improved in order to support direct bin -> JSON -> bin testing)");
if (!outname) {
console.warn('');
@ -102,7 +114,7 @@ function testBinAsync(nb) {
return;
}
fs.writeFileSync(path.basename(filename).replace(path.extname(filename), '.json'), JSON.stringify(json, null, 2), null);
fs.writeFileSync(outname, JSON.stringify(json, null, 2), null);
}
if ('json' === extname) {

4
dns.unpack-labels.js
View File

@ -46,6 +46,10 @@ exports.DNS_UNPACK_LABELS = function (ui8, ptr, q) {
//str.length = 0; // fast empty array
if (ui8.byteLength - total < len) {
//console.error('-1', ui8[total - 1]);
//console.error(' 0', ui8[total]);
//console.error(' 1', ui8[total + 1]);
//console.error(' 1', ui8[total + 2]);
throw new Error(
"Expected a string of length " + len
+ " but packet itself has " + (ui8.byteLength - total) + " bytes remaining"

30
packer/type.soa.js
View File

@ -1,6 +1,8 @@
(function (exports) {
'use strict';
// http://www.zytrax.com/books/dns/ch8/soa.html
// Value Meaning/Use
// Primary NS Variable length. The name of the Primary Master for the domain. May be a label, pointer, or any combination
// Admin MB Variable length. The administrator's mailbox. May be a label, pointer, or any combination
@ -10,8 +12,6 @@
// Expiration Limit Unsigned 32-bit integer
// Minimum TTL Unsigned 32-bit integer
exports.DNS_PACKER_TYPE_SOA = function (ab, dv, total, record) {
if(!record.name_server){
throw new Error("no name server for SOA record");
@ -23,16 +23,16 @@ exports.DNS_PACKER_TYPE_SOA = function (ab, dv, total, record) {
throw new Error("no serial number for SOA record");
}
if(!record.ref){
throw new Error("no serial number for SOA record");
throw new Error("no refresh for SOA record");
}
if(!record.ret){
throw new Error("no serial number for SOA record");
throw new Error("no update retry for SOA record");
}
if(!record.ex){
throw new Error("no serial number for SOA record");
throw new Error("no expiry for SOA record");
}
if(!record.nx){
throw new Error("no serial number for SOA record");
throw new Error("no nxdomain for SOA record");
}
var soaLen = 20; // take into account sn, ref, ret, ex, and nx
@ -40,9 +40,10 @@ exports.DNS_PACKER_TYPE_SOA = function (ab, dv, total, record) {
var rdLenIndex = total;
total += 2; // Save space for RDLENGTH
console.log('record.name_server', 1 + record.name_server.length, record.name_server);
// pack name_server which is a sequence of labels
record.name_server.split('.').forEach(function(label){
soaLen += 1 + label.length;
record.name_server.split('.').forEach(function (label) {
soaLen += (1 + label.length);
dv.setUint8(total, label.length, false);
total += 1;
@ -52,9 +53,14 @@ exports.DNS_PACKER_TYPE_SOA = function (ab, dv, total, record) {
total += 1;
});
});
// must be terminated by null when not using write null
dv.setUint8(total, 0, false);
total += 1;
soaLen += 1;
console.log('record.email_addr', 1 + record.email_addr.length, record.email_addr);
// pack email address which is a sequence of labels
record.email_addr.split('.').forEach(function (label){
record.email_addr.split('.').forEach(function (label) {
soaLen += 1 + label.length;
dv.setUint8(total, label.length, false);
@ -65,6 +71,10 @@ exports.DNS_PACKER_TYPE_SOA = function (ab, dv, total, record) {
total += 1;
});
});
// must be terminated by null when not using write null
dv.setUint8(total, 0, false);
total += 1;
soaLen += 1;
// pack all 32-bit values
dv.setUint32(total, parseInt(record.sn, 10), false);
@ -79,6 +89,8 @@ exports.DNS_PACKER_TYPE_SOA = function (ab, dv, total, record) {
total+=4;
// RDLENGTH
console.log('rdAt', rdLenIndex);
console.log('soaLen (lables + 2 + 20)', soaLen);
dv.setUint16(rdLenIndex, soaLen, false);
return total;

23
parser/type.soa.js
View File

@ -18,27 +18,31 @@ exports.DNS_PARSER_TYPE_SOA = function (ab, packet, record) {
var dv = new DataView(rdataAb);
// we need this information for this parser
var cpcount = unpackLabels(new Uint8Array(ab), record.rdstart, { byteLength: 0, cpcount: 0, labels: [], name: '' }).cpcount;
var offset = unpackLabels(new Uint8Array(ab), record.rdstart, { byteLength: 0, cpcount: 0, labels: [], name: '' }).byteLength;
var labels = unpackLabels(new Uint8Array(ab), record.rdstart, { byteLength: 0, cpcount: 0, labels: [], name: '' }).labels;
var labelInfo = unpackLabels(new Uint8Array(ab), record.rdstart, { byteLength: 0, cpcount: 0, labels: [], name: '' });
var cpcount = labelInfo.cpcount;
var offset = labelInfo.byteLength;
var labels = labelInfo.labels;
// Primary NS
record.name_server = unpackLabels(new Uint8Array(ab), record.rdstart, { byteLength: 0, cpcount: 0, labels: [], name: '' }).name;
record.name_server = labelInfo.name;
// TODO delete this commented out code after some testing
// (pretty sure it was unnecessary and it seemed to work on code with compression pointers just fine)
/*
// if there exists compression pointers in the rdata
if (cpcount > 0){
if (cpcount > 0) {
// do something awesome with compression pointers to get the email address
// I need the length of all the data before the email address starts.
// if there are compression pointers then there will be a byte to indicate the length of each label, the label,
// then there will be a compression pointer to grab the longest label.
var start = 2; // start or email_addr. take into account compression pointer and address length
for(var i = 0; i < labels.length; i++){
for (var i = 0; i < labels.length; i += 1) {
// increase start by the label length. the +1 is to take into account the next label size byte
start = start + labels[i].length + 1;
// check for cpcount. 2 counts behind
if(parseInt(dv.getUint8(start - 2), 10) === 192){
if (parseInt(dv.getUint8(start - 2), 10) === 192) {
record.email_addr = unpackLabels(new Uint8Array(ab), record.rdstart + start ,{ byteLength: 0, cpcount: 0, labels: [], name: '' }).name;
}
}
@ -47,6 +51,9 @@ exports.DNS_PARSER_TYPE_SOA = function (ab, packet, record) {
record.email_addr = unpackLabels(new Uint8Array(ab), record.rdstart + offset, { byteLength: 0, cpcount: 0, labels: [], name: '' }).name;
}
*/
record.email_addr = unpackLabels(new Uint8Array(ab), record.rdstart + offset, { byteLength: 0, cpcount: 0, labels: [], name: '' }).name;
// Serial Number
record.sn = dv.getUint32(dv.byteLength - 20, false);
// Refresh Interval
@ -58,9 +65,7 @@ exports.DNS_PARSER_TYPE_SOA = function (ab, packet, record) {
// Minimum TTL
record.nx = dv.getUint32(dv.byteLength - 4, false);
return record;
};
}('undefined' !== typeof window ? window : exports));