dns-suite.js/parser/type.soa.js

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(function (exports) {
'use strict';
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// 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
// Serial Number Unsigned 32-bit integer
// Refresh Interval Unsigned 32-bit integer
// Retry Interval Unsigned 32-bit integer
// Expiration Limit Unsigned 32-bit integer
// Minimum TTL Unsigned 32-bit integer
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var unpackLabels = exports.DNS_UNPACK_LABELS || require('../dns.unpack-labels.js').DNS_UNPACK_LABELS;
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exports.DNS_PARSER_TYPE_SOA = function (ab, packet, record) {
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//
// Look!
// http://www.peerwisdom.org/2013/05/15/dns-understanding-the-soa-record/
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var rdataAb = ab.slice(record.rdstart, record.rdstart + record.rdlength);
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var dv = new DataView(rdataAb);
// we need this information for this parser
var labelInfo = unpackLabels(new Uint8Array(ab), record.rdstart, { byteLength: 0, cpcount: 0, labels: [], name: '' });
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//var cpcount = labelInfo.cpcount;
var offset = labelInfo.byteLength;
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//var labels = labelInfo.labels;
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// Primary NS
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record.primary = labelInfo.name;
record.name_server = record.primary;
// 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) {
// 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 += 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) {
record.email_addr = unpackLabels(new Uint8Array(ab), record.rdstart + start ,{ byteLength: 0, cpcount: 0, labels: [], name: '' }).name;
}
}
} // if there are no compression pointers, we can get the email address directly from the offset
else {
record.email_addr = unpackLabels(new Uint8Array(ab), record.rdstart + offset, { byteLength: 0, cpcount: 0, labels: [], name: '' }).name;
}
*/
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record.admin = unpackLabels(new Uint8Array(ab), record.rdstart + offset, { byteLength: 0, cpcount: 0, labels: [], name: '' }).name;
record.email_addr = record.admin;
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// Serial Number
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record.serial = record.sn = dv.getUint32(dv.byteLength - 20, false);
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// Refresh Interval
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record.refresh = record.ref = dv.getUint32(dv.byteLength - 16, false);
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// Retry Interval
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record.retry = record.ret = dv.getUint32(dv.byteLength - 12, false);
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// Expiration Limit
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record.expiration = record.ex = dv.getUint32(dv.byteLength - 8, false);
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// Minimum TTL
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record.minimum = record.nx = dv.getUint32(dv.byteLength - 4, false);
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return record;
};
}('undefined' !== typeof window ? window : exports));