1570 lines
38 KiB
JavaScript
1570 lines
38 KiB
JavaScript
'use strict'
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const Buffer = require('buffer').Buffer
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const types = require('./types')
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const rcodes = require('./rcodes')
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const opcodes = require('./opcodes')
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const classes = require('./classes')
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const optioncodes = require('./optioncodes')
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const ip = require('@leichtgewicht/ip-codec')
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const QUERY_FLAG = 0
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const RESPONSE_FLAG = 1 << 15
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const FLUSH_MASK = 1 << 15
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const NOT_FLUSH_MASK = ~FLUSH_MASK
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const QU_MASK = 1 << 15
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const NOT_QU_MASK = ~QU_MASK
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const name = exports.name = {}
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name.encode = function (str, buf, offset) {
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if (!buf) buf = Buffer.alloc(name.encodingLength(str))
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if (!offset) offset = 0
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const oldOffset = offset
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// strip leading and trailing .
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const n = str.replace(/^\.|\.$/gm, '')
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if (n.length) {
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const list = n.split('.')
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for (let i = 0; i < list.length; i++) {
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const len = buf.write(list[i], offset + 1)
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buf[offset] = len
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offset += len + 1
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}
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}
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buf[offset++] = 0
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name.encode.bytes = offset - oldOffset
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return buf
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}
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name.encode.bytes = 0
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name.decode = function (buf, offset) {
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if (!offset) offset = 0
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const list = []
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let oldOffset = offset
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let totalLength = 0
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let consumedBytes = 0
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let jumped = false
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while (true) {
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if (offset >= buf.length) {
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throw new Error('Cannot decode name (buffer overflow)')
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}
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const len = buf[offset++]
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consumedBytes += jumped ? 0 : 1
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if (len === 0) {
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break
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} else if ((len & 0xc0) === 0) {
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if (offset + len > buf.length) {
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throw new Error('Cannot decode name (buffer overflow)')
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}
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totalLength += len + 1
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if (totalLength > 254) {
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throw new Error('Cannot decode name (name too long)')
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}
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list.push(buf.toString('utf-8', offset, offset + len))
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offset += len
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consumedBytes += jumped ? 0 : len
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} else if ((len & 0xc0) === 0xc0) {
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if (offset + 1 > buf.length) {
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throw new Error('Cannot decode name (buffer overflow)')
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}
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const jumpOffset = buf.readUInt16BE(offset - 1) - 0xc000
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if (jumpOffset >= oldOffset) {
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// Allow only pointers to prior data. RFC 1035, section 4.1.4 states:
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// "[...] an entire domain name or a list of labels at the end of a domain name
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// is replaced with a pointer to a prior occurance (sic) of the same name."
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throw new Error('Cannot decode name (bad pointer)')
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}
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offset = jumpOffset
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oldOffset = jumpOffset
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consumedBytes += jumped ? 0 : 1
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jumped = true
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} else {
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throw new Error('Cannot decode name (bad label)')
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}
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}
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name.decode.bytes = consumedBytes
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return list.length === 0 ? '.' : list.join('.')
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}
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name.decode.bytes = 0
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name.encodingLength = function (n) {
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if (n === '.' || n === '..') return 1
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return Buffer.byteLength(n.replace(/^\.|\.$/gm, '')) + 2
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}
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const string = {}
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string.encode = function (s, buf, offset) {
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if (!buf) buf = Buffer.alloc(string.encodingLength(s))
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if (!offset) offset = 0
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const len = buf.write(s, offset + 1)
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buf[offset] = len
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string.encode.bytes = len + 1
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return buf
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}
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string.encode.bytes = 0
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string.decode = function (buf, offset) {
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if (!offset) offset = 0
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const len = buf[offset]
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const s = buf.toString('utf-8', offset + 1, offset + 1 + len)
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string.decode.bytes = len + 1
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return s
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}
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string.decode.bytes = 0
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string.encodingLength = function (s) {
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return Buffer.byteLength(s) + 1
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}
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const header = {}
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header.encode = function (h, buf, offset) {
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if (!buf) buf = header.encodingLength(h)
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if (!offset) offset = 0
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const flags = (h.flags || 0) & 32767
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const type = h.type === 'response' ? RESPONSE_FLAG : QUERY_FLAG
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buf.writeUInt16BE(h.id || 0, offset)
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buf.writeUInt16BE(flags | type, offset + 2)
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buf.writeUInt16BE(h.questions.length, offset + 4)
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buf.writeUInt16BE(h.answers.length, offset + 6)
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buf.writeUInt16BE(h.authorities.length, offset + 8)
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buf.writeUInt16BE(h.additionals.length, offset + 10)
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return buf
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}
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header.encode.bytes = 12
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header.decode = function (buf, offset) {
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if (!offset) offset = 0
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if (buf.length < 12) throw new Error('Header must be 12 bytes')
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const flags = buf.readUInt16BE(offset + 2)
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return {
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id: buf.readUInt16BE(offset),
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type: flags & RESPONSE_FLAG ? 'response' : 'query',
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flags: flags & 32767,
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flag_qr: ((flags >> 15) & 0x1) === 1,
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opcode: opcodes.toString((flags >> 11) & 0xf),
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flag_aa: ((flags >> 10) & 0x1) === 1,
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flag_tc: ((flags >> 9) & 0x1) === 1,
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flag_rd: ((flags >> 8) & 0x1) === 1,
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flag_ra: ((flags >> 7) & 0x1) === 1,
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flag_z: ((flags >> 6) & 0x1) === 1,
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flag_ad: ((flags >> 5) & 0x1) === 1,
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flag_cd: ((flags >> 4) & 0x1) === 1,
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rcode: rcodes.toString(flags & 0xf),
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questions: new Array(buf.readUInt16BE(offset + 4)),
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answers: new Array(buf.readUInt16BE(offset + 6)),
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authorities: new Array(buf.readUInt16BE(offset + 8)),
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additionals: new Array(buf.readUInt16BE(offset + 10))
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}
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}
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header.decode.bytes = 12
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header.encodingLength = function () {
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return 12
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}
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const runknown = exports.unknown = {}
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runknown.encode = function (data, buf, offset) {
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if (!buf) buf = Buffer.alloc(runknown.encodingLength(data))
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if (!offset) offset = 0
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buf.writeUInt16BE(data.length, offset)
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data.copy(buf, offset + 2)
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runknown.encode.bytes = data.length + 2
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return buf
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}
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runknown.encode.bytes = 0
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runknown.decode = function (buf, offset) {
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if (!offset) offset = 0
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const len = buf.readUInt16BE(offset)
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const data = buf.slice(offset + 2, offset + 2 + len)
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runknown.decode.bytes = len + 2
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return data
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}
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runknown.decode.bytes = 0
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runknown.encodingLength = function (data) {
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return data.length + 2
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}
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const rns = exports.ns = {}
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rns.encode = function (data, buf, offset) {
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if (!buf) buf = Buffer.alloc(rns.encodingLength(data))
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if (!offset) offset = 0
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name.encode(data, buf, offset + 2)
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buf.writeUInt16BE(name.encode.bytes, offset)
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rns.encode.bytes = name.encode.bytes + 2
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return buf
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}
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rns.encode.bytes = 0
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rns.decode = function (buf, offset) {
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if (!offset) offset = 0
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const len = buf.readUInt16BE(offset)
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const dd = name.decode(buf, offset + 2)
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rns.decode.bytes = len + 2
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return dd
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}
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rns.decode.bytes = 0
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rns.encodingLength = function (data) {
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return name.encodingLength(data) + 2
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}
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const rsoa = exports.soa = {}
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rsoa.encode = function (data, buf, offset) {
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if (!buf) buf = Buffer.alloc(rsoa.encodingLength(data))
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if (!offset) offset = 0
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const oldOffset = offset
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offset += 2
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name.encode(data.mname, buf, offset)
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offset += name.encode.bytes
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name.encode(data.rname, buf, offset)
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offset += name.encode.bytes
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buf.writeUInt32BE(data.serial || 0, offset)
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offset += 4
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buf.writeUInt32BE(data.refresh || 0, offset)
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offset += 4
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buf.writeUInt32BE(data.retry || 0, offset)
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offset += 4
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buf.writeUInt32BE(data.expire || 0, offset)
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offset += 4
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buf.writeUInt32BE(data.minimum || 0, offset)
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offset += 4
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buf.writeUInt16BE(offset - oldOffset - 2, oldOffset)
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rsoa.encode.bytes = offset - oldOffset
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return buf
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}
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rsoa.encode.bytes = 0
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rsoa.decode = function (buf, offset) {
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if (!offset) offset = 0
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const oldOffset = offset
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const data = {}
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offset += 2
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data.mname = name.decode(buf, offset)
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offset += name.decode.bytes
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data.rname = name.decode(buf, offset)
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offset += name.decode.bytes
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data.serial = buf.readUInt32BE(offset)
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offset += 4
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data.refresh = buf.readUInt32BE(offset)
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offset += 4
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data.retry = buf.readUInt32BE(offset)
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offset += 4
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data.expire = buf.readUInt32BE(offset)
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offset += 4
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data.minimum = buf.readUInt32BE(offset)
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offset += 4
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rsoa.decode.bytes = offset - oldOffset
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return data
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}
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rsoa.decode.bytes = 0
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rsoa.encodingLength = function (data) {
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return 22 + name.encodingLength(data.mname) + name.encodingLength(data.rname)
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}
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const rtxt = exports.txt = {}
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rtxt.encode = function (data, buf, offset) {
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if (!Array.isArray(data)) data = [data]
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for (let i = 0; i < data.length; i++) {
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if (typeof data[i] === 'string') {
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data[i] = Buffer.from(data[i])
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}
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if (!Buffer.isBuffer(data[i])) {
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throw new Error('Must be a Buffer')
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}
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}
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if (!buf) buf = Buffer.alloc(rtxt.encodingLength(data))
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if (!offset) offset = 0
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const oldOffset = offset
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offset += 2
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data.forEach(function (d) {
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buf[offset++] = d.length
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d.copy(buf, offset, 0, d.length)
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offset += d.length
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})
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buf.writeUInt16BE(offset - oldOffset - 2, oldOffset)
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rtxt.encode.bytes = offset - oldOffset
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return buf
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}
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rtxt.encode.bytes = 0
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rtxt.decode = function (buf, offset) {
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if (!offset) offset = 0
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const oldOffset = offset
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let remaining = buf.readUInt16BE(offset)
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offset += 2
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let data = []
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while (remaining > 0) {
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const len = buf[offset++]
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--remaining
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if (remaining < len) {
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throw new Error('Buffer overflow')
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}
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data.push(buf.slice(offset, offset + len))
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offset += len
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remaining -= len
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}
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rtxt.decode.bytes = offset - oldOffset
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return data
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}
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rtxt.decode.bytes = 0
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rtxt.encodingLength = function (data) {
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if (!Array.isArray(data)) data = [data]
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let length = 2
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data.forEach(function (buf) {
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if (typeof buf === 'string') {
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length += Buffer.byteLength(buf) + 1
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} else {
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length += buf.length + 1
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}
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})
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return length
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}
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const rnull = exports.null = {}
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rnull.encode = function (data, buf, offset) {
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if (!buf) buf = Buffer.alloc(rnull.encodingLength(data))
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if (!offset) offset = 0
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if (typeof data === 'string') data = Buffer.from(data)
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if (!data) data = Buffer.alloc(0)
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const oldOffset = offset
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offset += 2
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const len = data.length
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data.copy(buf, offset, 0, len)
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offset += len
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buf.writeUInt16BE(offset - oldOffset - 2, oldOffset)
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rnull.encode.bytes = offset - oldOffset
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return buf
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}
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rnull.encode.bytes = 0
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rnull.decode = function (buf, offset) {
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if (!offset) offset = 0
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const oldOffset = offset
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const len = buf.readUInt16BE(offset)
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offset += 2
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const data = buf.slice(offset, offset + len)
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offset += len
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rnull.decode.bytes = offset - oldOffset
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return data
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}
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rnull.decode.bytes = 0
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rnull.encodingLength = function (data) {
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if (!data) return 2
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return (Buffer.isBuffer(data) ? data.length : Buffer.byteLength(data)) + 2
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}
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const rhinfo = exports.hinfo = {}
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rhinfo.encode = function (data, buf, offset) {
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if (!buf) buf = Buffer.alloc(rhinfo.encodingLength(data))
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if (!offset) offset = 0
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const oldOffset = offset
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offset += 2
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string.encode(data.cpu, buf, offset)
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offset += string.encode.bytes
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string.encode(data.os, buf, offset)
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offset += string.encode.bytes
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buf.writeUInt16BE(offset - oldOffset - 2, oldOffset)
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rhinfo.encode.bytes = offset - oldOffset
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return buf
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}
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rhinfo.encode.bytes = 0
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rhinfo.decode = function (buf, offset) {
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if (!offset) offset = 0
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const oldOffset = offset
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const data = {}
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offset += 2
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data.cpu = string.decode(buf, offset)
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offset += string.decode.bytes
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data.os = string.decode(buf, offset)
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offset += string.decode.bytes
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rhinfo.decode.bytes = offset - oldOffset
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return data
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}
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rhinfo.decode.bytes = 0
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rhinfo.encodingLength = function (data) {
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return string.encodingLength(data.cpu) + string.encodingLength(data.os) + 2
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}
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const rptr = exports.ptr = {}
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const rcname = exports.cname = rptr
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const rdname = exports.dname = rptr
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rptr.encode = function (data, buf, offset) {
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if (!buf) buf = Buffer.alloc(rptr.encodingLength(data))
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if (!offset) offset = 0
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name.encode(data, buf, offset + 2)
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buf.writeUInt16BE(name.encode.bytes, offset)
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rptr.encode.bytes = name.encode.bytes + 2
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return buf
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}
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rptr.encode.bytes = 0
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rptr.decode = function (buf, offset) {
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if (!offset) offset = 0
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const data = name.decode(buf, offset + 2)
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rptr.decode.bytes = name.decode.bytes + 2
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return data
|
|
}
|
|
|
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rptr.decode.bytes = 0
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|
|
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rptr.encodingLength = function (data) {
|
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return name.encodingLength(data) + 2
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|
}
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|
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const rsrv = exports.srv = {}
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rsrv.encode = function (data, buf, offset) {
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if (!buf) buf = Buffer.alloc(rsrv.encodingLength(data))
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if (!offset) offset = 0
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buf.writeUInt16BE(data.priority || 0, offset + 2)
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buf.writeUInt16BE(data.weight || 0, offset + 4)
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buf.writeUInt16BE(data.port || 0, offset + 6)
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name.encode(data.target, buf, offset + 8)
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const len = name.encode.bytes + 6
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buf.writeUInt16BE(len, offset)
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rsrv.encode.bytes = len + 2
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return buf
|
|
}
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|
|
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rsrv.encode.bytes = 0
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|
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rsrv.decode = function (buf, offset) {
|
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if (!offset) offset = 0
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|
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const len = buf.readUInt16BE(offset)
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|
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const data = {}
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data.priority = buf.readUInt16BE(offset + 2)
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|
data.weight = buf.readUInt16BE(offset + 4)
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data.port = buf.readUInt16BE(offset + 6)
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|
data.target = name.decode(buf, offset + 8)
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rsrv.decode.bytes = len + 2
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return data
|
|
}
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|
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rsrv.decode.bytes = 0
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|
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rsrv.encodingLength = function (data) {
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return 8 + name.encodingLength(data.target)
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}
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|
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const rcaa = exports.caa = {}
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|
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rcaa.ISSUER_CRITICAL = 1 << 7
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|
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rcaa.encode = function (data, buf, offset) {
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const len = rcaa.encodingLength(data)
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if (!buf) buf = Buffer.alloc(rcaa.encodingLength(data))
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if (!offset) offset = 0
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|
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if (data.issuerCritical) {
|
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data.flags = rcaa.ISSUER_CRITICAL
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}
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|
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buf.writeUInt16BE(len - 2, offset)
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offset += 2
|
|
buf.writeUInt8(data.flags || 0, offset)
|
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offset += 1
|
|
string.encode(data.tag, buf, offset)
|
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offset += string.encode.bytes
|
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buf.write(data.value, offset)
|
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offset += Buffer.byteLength(data.value)
|
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|
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rcaa.encode.bytes = len
|
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return buf
|
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}
|
|
|
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rcaa.encode.bytes = 0
|
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|
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rcaa.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
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|
|
const len = buf.readUInt16BE(offset)
|
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offset += 2
|
|
|
|
const oldOffset = offset
|
|
const data = {}
|
|
data.flags = buf.readUInt8(offset)
|
|
offset += 1
|
|
data.tag = string.decode(buf, offset)
|
|
offset += string.decode.bytes
|
|
data.value = buf.toString('utf-8', offset, oldOffset + len)
|
|
|
|
data.issuerCritical = !!(data.flags & rcaa.ISSUER_CRITICAL)
|
|
|
|
rcaa.decode.bytes = len + 2
|
|
|
|
return data
|
|
}
|
|
|
|
rcaa.decode.bytes = 0
|
|
|
|
rcaa.encodingLength = function (data) {
|
|
return string.encodingLength(data.tag) + string.encodingLength(data.value) + 2
|
|
}
|
|
|
|
const rmx = exports.mx = {}
|
|
|
|
rmx.encode = function (data, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(rmx.encodingLength(data))
|
|
if (!offset) offset = 0
|
|
|
|
const oldOffset = offset
|
|
offset += 2
|
|
buf.writeUInt16BE(data.preference || 0, offset)
|
|
offset += 2
|
|
name.encode(data.exchange, buf, offset)
|
|
offset += name.encode.bytes
|
|
|
|
buf.writeUInt16BE(offset - oldOffset - 2, oldOffset)
|
|
rmx.encode.bytes = offset - oldOffset
|
|
return buf
|
|
}
|
|
|
|
rmx.encode.bytes = 0
|
|
|
|
rmx.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
|
|
const oldOffset = offset
|
|
|
|
const data = {}
|
|
offset += 2
|
|
data.preference = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
data.exchange = name.decode(buf, offset)
|
|
offset += name.decode.bytes
|
|
|
|
rmx.decode.bytes = offset - oldOffset
|
|
return data
|
|
}
|
|
|
|
rmx.encodingLength = function (data) {
|
|
return 4 + name.encodingLength(data.exchange)
|
|
}
|
|
|
|
const ra = exports.a = {}
|
|
|
|
ra.encode = function (host, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(ra.encodingLength(host))
|
|
if (!offset) offset = 0
|
|
|
|
buf.writeUInt16BE(4, offset)
|
|
offset += 2
|
|
ip.v4.encode(host, buf, offset)
|
|
ra.encode.bytes = 6
|
|
return buf
|
|
}
|
|
|
|
ra.encode.bytes = 0
|
|
|
|
ra.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
|
|
offset += 2
|
|
const host = ip.v4.decode(buf, offset)
|
|
ra.decode.bytes = 6
|
|
return host
|
|
}
|
|
|
|
ra.decode.bytes = 0
|
|
|
|
ra.encodingLength = function () {
|
|
return 6
|
|
}
|
|
|
|
const raaaa = exports.aaaa = {}
|
|
|
|
raaaa.encode = function (host, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(raaaa.encodingLength(host))
|
|
if (!offset) offset = 0
|
|
|
|
buf.writeUInt16BE(16, offset)
|
|
offset += 2
|
|
ip.v6.encode(host, buf, offset)
|
|
raaaa.encode.bytes = 18
|
|
return buf
|
|
}
|
|
|
|
raaaa.encode.bytes = 0
|
|
|
|
raaaa.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
|
|
offset += 2
|
|
const host = ip.v6.decode(buf, offset)
|
|
raaaa.decode.bytes = 18
|
|
return host
|
|
}
|
|
|
|
raaaa.decode.bytes = 0
|
|
|
|
raaaa.encodingLength = function () {
|
|
return 18
|
|
}
|
|
|
|
const roption = exports.option = {}
|
|
|
|
roption.encode = function (option, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(roption.encodingLength(option))
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
const code = optioncodes.toCode(option.code)
|
|
buf.writeUInt16BE(code, offset)
|
|
offset += 2
|
|
if (option.data) {
|
|
buf.writeUInt16BE(option.data.length, offset)
|
|
offset += 2
|
|
option.data.copy(buf, offset)
|
|
offset += option.data.length
|
|
} else {
|
|
switch (code) {
|
|
// case 3: NSID. No encode makes sense.
|
|
// case 5,6,7: Not implementable
|
|
case 8: // ECS
|
|
// note: do IP math before calling
|
|
const spl = option.sourcePrefixLength || 0
|
|
const fam = option.family || ip.familyOf(option.ip)
|
|
const ipBuf = ip.encode(option.ip, Buffer.alloc)
|
|
const ipLen = Math.ceil(spl / 8)
|
|
buf.writeUInt16BE(ipLen + 4, offset)
|
|
offset += 2
|
|
buf.writeUInt16BE(fam, offset)
|
|
offset += 2
|
|
buf.writeUInt8(spl, offset++)
|
|
buf.writeUInt8(option.scopePrefixLength || 0, offset++)
|
|
|
|
ipBuf.copy(buf, offset, 0, ipLen)
|
|
offset += ipLen
|
|
break
|
|
// case 9: EXPIRE (experimental)
|
|
// case 10: COOKIE. No encode makes sense.
|
|
case 11: // KEEP-ALIVE
|
|
if (option.timeout) {
|
|
buf.writeUInt16BE(2, offset)
|
|
offset += 2
|
|
buf.writeUInt16BE(option.timeout, offset)
|
|
offset += 2
|
|
} else {
|
|
buf.writeUInt16BE(0, offset)
|
|
offset += 2
|
|
}
|
|
break
|
|
case 12: // PADDING
|
|
const len = option.length || 0
|
|
buf.writeUInt16BE(len, offset)
|
|
offset += 2
|
|
buf.fill(0, offset, offset + len)
|
|
offset += len
|
|
break
|
|
// case 13: CHAIN. Experimental.
|
|
case 14: // KEY-TAG
|
|
const tagsLen = option.tags.length * 2
|
|
buf.writeUInt16BE(tagsLen, offset)
|
|
offset += 2
|
|
for (const tag of option.tags) {
|
|
buf.writeUInt16BE(tag, offset)
|
|
offset += 2
|
|
}
|
|
break
|
|
default:
|
|
throw new Error(`Unknown roption code: ${option.code}`)
|
|
}
|
|
}
|
|
|
|
roption.encode.bytes = offset - oldOffset
|
|
return buf
|
|
}
|
|
|
|
roption.encode.bytes = 0
|
|
|
|
roption.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
const option = {}
|
|
option.code = buf.readUInt16BE(offset)
|
|
option.type = optioncodes.toString(option.code)
|
|
offset += 2
|
|
const len = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
option.data = buf.slice(offset, offset + len)
|
|
switch (option.code) {
|
|
// case 3: NSID. No decode makes sense.
|
|
case 8: // ECS
|
|
option.family = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
option.sourcePrefixLength = buf.readUInt8(offset++)
|
|
option.scopePrefixLength = buf.readUInt8(offset++)
|
|
const padded = Buffer.alloc((option.family === 1) ? 4 : 16)
|
|
buf.copy(padded, 0, offset, offset + len - 4)
|
|
option.ip = ip.decode(padded)
|
|
break
|
|
// case 12: Padding. No decode makes sense.
|
|
case 11: // KEEP-ALIVE
|
|
if (len > 0) {
|
|
option.timeout = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
}
|
|
break
|
|
case 14:
|
|
option.tags = []
|
|
for (let i = 0; i < len; i += 2) {
|
|
option.tags.push(buf.readUInt16BE(offset))
|
|
offset += 2
|
|
}
|
|
// don't worry about default. caller will use data if desired
|
|
}
|
|
|
|
roption.decode.bytes = len + 4
|
|
return option
|
|
}
|
|
|
|
roption.decode.bytes = 0
|
|
|
|
roption.encodingLength = function (option) {
|
|
if (option.data) {
|
|
return option.data.length + 4
|
|
}
|
|
const code = optioncodes.toCode(option.code)
|
|
switch (code) {
|
|
case 8: // ECS
|
|
const spl = option.sourcePrefixLength || 0
|
|
return Math.ceil(spl / 8) + 8
|
|
case 11: // KEEP-ALIVE
|
|
return (typeof option.timeout === 'number') ? 6 : 4
|
|
case 12: // PADDING
|
|
return option.length + 4
|
|
case 14: // KEY-TAG
|
|
return 4 + (option.tags.length * 2)
|
|
}
|
|
throw new Error(`Unknown roption code: ${option.code}`)
|
|
}
|
|
|
|
const ropt = exports.opt = {}
|
|
|
|
ropt.encode = function (options, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(ropt.encodingLength(options))
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
const rdlen = encodingLengthList(options, roption)
|
|
buf.writeUInt16BE(rdlen, offset)
|
|
offset = encodeList(options, roption, buf, offset + 2)
|
|
|
|
ropt.encode.bytes = offset - oldOffset
|
|
return buf
|
|
}
|
|
|
|
ropt.encode.bytes = 0
|
|
|
|
ropt.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
const options = []
|
|
let rdlen = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
let o = 0
|
|
while (rdlen > 0) {
|
|
options[o++] = roption.decode(buf, offset)
|
|
offset += roption.decode.bytes
|
|
rdlen -= roption.decode.bytes
|
|
}
|
|
ropt.decode.bytes = offset - oldOffset
|
|
return options
|
|
}
|
|
|
|
ropt.decode.bytes = 0
|
|
|
|
ropt.encodingLength = function (options) {
|
|
return 2 + encodingLengthList(options || [], roption)
|
|
}
|
|
|
|
const rdnskey = exports.dnskey = {}
|
|
|
|
rdnskey.PROTOCOL_DNSSEC = 3
|
|
rdnskey.ZONE_KEY = 0x80
|
|
rdnskey.SECURE_ENTRYPOINT = 0x8000
|
|
|
|
rdnskey.encode = function (key, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(rdnskey.encodingLength(key))
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
const keydata = key.key
|
|
if (!Buffer.isBuffer(keydata)) {
|
|
throw new Error('Key must be a Buffer')
|
|
}
|
|
|
|
offset += 2 // Leave space for length
|
|
buf.writeUInt16BE(key.flags, offset)
|
|
offset += 2
|
|
buf.writeUInt8(rdnskey.PROTOCOL_DNSSEC, offset)
|
|
offset += 1
|
|
buf.writeUInt8(key.algorithm, offset)
|
|
offset += 1
|
|
keydata.copy(buf, offset, 0, keydata.length)
|
|
offset += keydata.length
|
|
|
|
rdnskey.encode.bytes = offset - oldOffset
|
|
buf.writeUInt16BE(rdnskey.encode.bytes - 2, oldOffset)
|
|
return buf
|
|
}
|
|
|
|
rdnskey.encode.bytes = 0
|
|
|
|
rdnskey.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
var key = {}
|
|
var length = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
key.flags = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
if (buf.readUInt8(offset) !== rdnskey.PROTOCOL_DNSSEC) {
|
|
throw new Error('Protocol must be 3')
|
|
}
|
|
offset += 1
|
|
key.algorithm = buf.readUInt8(offset)
|
|
offset += 1
|
|
key.key = buf.slice(offset, oldOffset + length + 2)
|
|
offset += key.key.length
|
|
rdnskey.decode.bytes = offset - oldOffset
|
|
return key
|
|
}
|
|
|
|
rdnskey.decode.bytes = 0
|
|
|
|
rdnskey.encodingLength = function (key) {
|
|
return 6 + Buffer.byteLength(key.key)
|
|
}
|
|
|
|
const rrrsig = exports.rrsig = {}
|
|
|
|
rrrsig.encode = function (sig, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(rrrsig.encodingLength(sig))
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
const signature = sig.signature
|
|
if (!Buffer.isBuffer(signature)) {
|
|
throw new Error('Signature must be a Buffer')
|
|
}
|
|
|
|
offset += 2 // Leave space for length
|
|
buf.writeUInt16BE(types.toType(sig.typeCovered), offset)
|
|
offset += 2
|
|
buf.writeUInt8(sig.algorithm, offset)
|
|
offset += 1
|
|
buf.writeUInt8(sig.labels, offset)
|
|
offset += 1
|
|
buf.writeUInt32BE(sig.originalTTL, offset)
|
|
offset += 4
|
|
buf.writeUInt32BE(sig.expiration, offset)
|
|
offset += 4
|
|
buf.writeUInt32BE(sig.inception, offset)
|
|
offset += 4
|
|
buf.writeUInt16BE(sig.keyTag, offset)
|
|
offset += 2
|
|
name.encode(sig.signersName, buf, offset)
|
|
offset += name.encode.bytes
|
|
signature.copy(buf, offset, 0, signature.length)
|
|
offset += signature.length
|
|
|
|
rrrsig.encode.bytes = offset - oldOffset
|
|
buf.writeUInt16BE(rrrsig.encode.bytes - 2, oldOffset)
|
|
return buf
|
|
}
|
|
|
|
rrrsig.encode.bytes = 0
|
|
|
|
rrrsig.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
var sig = {}
|
|
var length = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
sig.typeCovered = types.toString(buf.readUInt16BE(offset))
|
|
offset += 2
|
|
sig.algorithm = buf.readUInt8(offset)
|
|
offset += 1
|
|
sig.labels = buf.readUInt8(offset)
|
|
offset += 1
|
|
sig.originalTTL = buf.readUInt32BE(offset)
|
|
offset += 4
|
|
sig.expiration = buf.readUInt32BE(offset)
|
|
offset += 4
|
|
sig.inception = buf.readUInt32BE(offset)
|
|
offset += 4
|
|
sig.keyTag = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
sig.signersName = name.decode(buf, offset)
|
|
offset += name.decode.bytes
|
|
sig.signature = buf.slice(offset, oldOffset + length + 2)
|
|
offset += sig.signature.length
|
|
rrrsig.decode.bytes = offset - oldOffset
|
|
return sig
|
|
}
|
|
|
|
rrrsig.decode.bytes = 0
|
|
|
|
rrrsig.encodingLength = function (sig) {
|
|
return 20 +
|
|
name.encodingLength(sig.signersName) +
|
|
Buffer.byteLength(sig.signature)
|
|
}
|
|
|
|
const rrp = exports.rp = {}
|
|
|
|
rrp.encode = function (data, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(rrp.encodingLength(data))
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
offset += 2 // Leave space for length
|
|
name.encode(data.mbox || '.', buf, offset)
|
|
offset += name.encode.bytes
|
|
name.encode(data.txt || '.', buf, offset)
|
|
offset += name.encode.bytes
|
|
rrp.encode.bytes = offset - oldOffset
|
|
buf.writeUInt16BE(rrp.encode.bytes - 2, oldOffset)
|
|
return buf
|
|
}
|
|
|
|
rrp.encode.bytes = 0
|
|
|
|
rrp.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
const data = {}
|
|
offset += 2
|
|
data.mbox = name.decode(buf, offset) || '.'
|
|
offset += name.decode.bytes
|
|
data.txt = name.decode(buf, offset) || '.'
|
|
offset += name.decode.bytes
|
|
rrp.decode.bytes = offset - oldOffset
|
|
return data
|
|
}
|
|
|
|
rrp.decode.bytes = 0
|
|
|
|
rrp.encodingLength = function (data) {
|
|
return 2 + name.encodingLength(data.mbox || '.') + name.encodingLength(data.txt || '.')
|
|
}
|
|
|
|
const typebitmap = {}
|
|
|
|
typebitmap.encode = function (typelist, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(typebitmap.encodingLength(typelist))
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
var typesByWindow = []
|
|
for (var i = 0; i < typelist.length; i++) {
|
|
var typeid = types.toType(typelist[i])
|
|
if (typesByWindow[typeid >> 8] === undefined) {
|
|
typesByWindow[typeid >> 8] = []
|
|
}
|
|
typesByWindow[typeid >> 8][(typeid >> 3) & 0x1F] |= 1 << (7 - (typeid & 0x7))
|
|
}
|
|
|
|
for (i = 0; i < typesByWindow.length; i++) {
|
|
if (typesByWindow[i] !== undefined) {
|
|
var windowBuf = Buffer.from(typesByWindow[i])
|
|
buf.writeUInt8(i, offset)
|
|
offset += 1
|
|
buf.writeUInt8(windowBuf.length, offset)
|
|
offset += 1
|
|
windowBuf.copy(buf, offset)
|
|
offset += windowBuf.length
|
|
}
|
|
}
|
|
|
|
typebitmap.encode.bytes = offset - oldOffset
|
|
return buf
|
|
}
|
|
|
|
typebitmap.encode.bytes = 0
|
|
|
|
typebitmap.decode = function (buf, offset, length) {
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
var typelist = []
|
|
while (offset - oldOffset < length) {
|
|
var window = buf.readUInt8(offset)
|
|
offset += 1
|
|
var windowLength = buf.readUInt8(offset)
|
|
offset += 1
|
|
for (var i = 0; i < windowLength; i++) {
|
|
var b = buf.readUInt8(offset + i)
|
|
for (var j = 0; j < 8; j++) {
|
|
if (b & (1 << (7 - j))) {
|
|
var typeid = types.toString((window << 8) | (i << 3) | j)
|
|
typelist.push(typeid)
|
|
}
|
|
}
|
|
}
|
|
offset += windowLength
|
|
}
|
|
|
|
typebitmap.decode.bytes = offset - oldOffset
|
|
return typelist
|
|
}
|
|
|
|
typebitmap.decode.bytes = 0
|
|
|
|
typebitmap.encodingLength = function (typelist) {
|
|
var extents = []
|
|
for (var i = 0; i < typelist.length; i++) {
|
|
var typeid = types.toType(typelist[i])
|
|
extents[typeid >> 8] = Math.max(extents[typeid >> 8] || 0, typeid & 0xFF)
|
|
}
|
|
|
|
var len = 0
|
|
for (i = 0; i < extents.length; i++) {
|
|
if (extents[i] !== undefined) {
|
|
len += 2 + Math.ceil((extents[i] + 1) / 8)
|
|
}
|
|
}
|
|
|
|
return len
|
|
}
|
|
|
|
const rnsec = exports.nsec = {}
|
|
|
|
rnsec.encode = function (record, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(rnsec.encodingLength(record))
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
offset += 2 // Leave space for length
|
|
name.encode(record.nextDomain, buf, offset)
|
|
offset += name.encode.bytes
|
|
typebitmap.encode(record.rrtypes, buf, offset)
|
|
offset += typebitmap.encode.bytes
|
|
|
|
rnsec.encode.bytes = offset - oldOffset
|
|
buf.writeUInt16BE(rnsec.encode.bytes - 2, oldOffset)
|
|
return buf
|
|
}
|
|
|
|
rnsec.encode.bytes = 0
|
|
|
|
rnsec.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
var record = {}
|
|
var length = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
record.nextDomain = name.decode(buf, offset)
|
|
offset += name.decode.bytes
|
|
record.rrtypes = typebitmap.decode(buf, offset, length - (offset - oldOffset))
|
|
offset += typebitmap.decode.bytes
|
|
|
|
rnsec.decode.bytes = offset - oldOffset
|
|
return record
|
|
}
|
|
|
|
rnsec.decode.bytes = 0
|
|
|
|
rnsec.encodingLength = function (record) {
|
|
return 2 +
|
|
name.encodingLength(record.nextDomain) +
|
|
typebitmap.encodingLength(record.rrtypes)
|
|
}
|
|
|
|
const rnsec3 = exports.nsec3 = {}
|
|
|
|
rnsec3.encode = function (record, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(rnsec3.encodingLength(record))
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
const salt = record.salt
|
|
if (!Buffer.isBuffer(salt)) {
|
|
throw new Error('salt must be a Buffer')
|
|
}
|
|
|
|
const nextDomain = record.nextDomain
|
|
if (!Buffer.isBuffer(nextDomain)) {
|
|
throw new Error('nextDomain must be a Buffer')
|
|
}
|
|
|
|
offset += 2 // Leave space for length
|
|
buf.writeUInt8(record.algorithm, offset)
|
|
offset += 1
|
|
buf.writeUInt8(record.flags, offset)
|
|
offset += 1
|
|
buf.writeUInt16BE(record.iterations, offset)
|
|
offset += 2
|
|
buf.writeUInt8(salt.length, offset)
|
|
offset += 1
|
|
salt.copy(buf, offset, 0, salt.length)
|
|
offset += salt.length
|
|
buf.writeUInt8(nextDomain.length, offset)
|
|
offset += 1
|
|
nextDomain.copy(buf, offset, 0, nextDomain.length)
|
|
offset += nextDomain.length
|
|
typebitmap.encode(record.rrtypes, buf, offset)
|
|
offset += typebitmap.encode.bytes
|
|
|
|
rnsec3.encode.bytes = offset - oldOffset
|
|
buf.writeUInt16BE(rnsec3.encode.bytes - 2, oldOffset)
|
|
return buf
|
|
}
|
|
|
|
rnsec3.encode.bytes = 0
|
|
|
|
rnsec3.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
var record = {}
|
|
var length = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
record.algorithm = buf.readUInt8(offset)
|
|
offset += 1
|
|
record.flags = buf.readUInt8(offset)
|
|
offset += 1
|
|
record.iterations = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
const saltLength = buf.readUInt8(offset)
|
|
offset += 1
|
|
record.salt = buf.slice(offset, offset + saltLength)
|
|
offset += saltLength
|
|
const hashLength = buf.readUInt8(offset)
|
|
offset += 1
|
|
record.nextDomain = buf.slice(offset, offset + hashLength)
|
|
offset += hashLength
|
|
record.rrtypes = typebitmap.decode(buf, offset, length - (offset - oldOffset))
|
|
offset += typebitmap.decode.bytes
|
|
|
|
rnsec3.decode.bytes = offset - oldOffset
|
|
return record
|
|
}
|
|
|
|
rnsec3.decode.bytes = 0
|
|
|
|
rnsec3.encodingLength = function (record) {
|
|
return 8 +
|
|
record.salt.length +
|
|
record.nextDomain.length +
|
|
typebitmap.encodingLength(record.rrtypes)
|
|
}
|
|
|
|
const rds = exports.ds = {}
|
|
|
|
rds.encode = function (digest, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(rds.encodingLength(digest))
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
const digestdata = digest.digest
|
|
if (!Buffer.isBuffer(digestdata)) {
|
|
throw new Error('Digest must be a Buffer')
|
|
}
|
|
|
|
offset += 2 // Leave space for length
|
|
buf.writeUInt16BE(digest.keyTag, offset)
|
|
offset += 2
|
|
buf.writeUInt8(digest.algorithm, offset)
|
|
offset += 1
|
|
buf.writeUInt8(digest.digestType, offset)
|
|
offset += 1
|
|
digestdata.copy(buf, offset, 0, digestdata.length)
|
|
offset += digestdata.length
|
|
|
|
rds.encode.bytes = offset - oldOffset
|
|
buf.writeUInt16BE(rds.encode.bytes - 2, oldOffset)
|
|
return buf
|
|
}
|
|
|
|
rds.encode.bytes = 0
|
|
|
|
rds.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
const oldOffset = offset
|
|
|
|
var digest = {}
|
|
var length = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
digest.keyTag = buf.readUInt16BE(offset)
|
|
offset += 2
|
|
digest.algorithm = buf.readUInt8(offset)
|
|
offset += 1
|
|
digest.digestType = buf.readUInt8(offset)
|
|
offset += 1
|
|
digest.digest = buf.slice(offset, oldOffset + length + 2)
|
|
offset += digest.digest.length
|
|
rds.decode.bytes = offset - oldOffset
|
|
return digest
|
|
}
|
|
|
|
rds.decode.bytes = 0
|
|
|
|
rds.encodingLength = function (digest) {
|
|
return 6 + Buffer.byteLength(digest.digest)
|
|
}
|
|
|
|
const renc = exports.record = function (type) {
|
|
switch (type.toUpperCase()) {
|
|
case 'A': return ra
|
|
case 'PTR': return rptr
|
|
case 'CNAME': return rcname
|
|
case 'DNAME': return rdname
|
|
case 'TXT': return rtxt
|
|
case 'NULL': return rnull
|
|
case 'AAAA': return raaaa
|
|
case 'SRV': return rsrv
|
|
case 'HINFO': return rhinfo
|
|
case 'CAA': return rcaa
|
|
case 'NS': return rns
|
|
case 'SOA': return rsoa
|
|
case 'MX': return rmx
|
|
case 'OPT': return ropt
|
|
case 'DNSKEY': return rdnskey
|
|
case 'RRSIG': return rrrsig
|
|
case 'RP': return rrp
|
|
case 'NSEC': return rnsec
|
|
case 'NSEC3': return rnsec3
|
|
case 'DS': return rds
|
|
}
|
|
return runknown
|
|
}
|
|
|
|
const answer = exports.answer = {}
|
|
|
|
answer.encode = function (a, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(answer.encodingLength(a))
|
|
if (!offset) offset = 0
|
|
|
|
const oldOffset = offset
|
|
|
|
name.encode(a.name, buf, offset)
|
|
offset += name.encode.bytes
|
|
|
|
buf.writeUInt16BE(types.toType(a.type), offset)
|
|
|
|
if (a.type.toUpperCase() === 'OPT') {
|
|
if (a.name !== '.') {
|
|
throw new Error('OPT name must be root.')
|
|
}
|
|
buf.writeUInt16BE(a.udpPayloadSize || 4096, offset + 2)
|
|
buf.writeUInt8(a.extendedRcode || 0, offset + 4)
|
|
buf.writeUInt8(a.ednsVersion || 0, offset + 5)
|
|
buf.writeUInt16BE(a.flags || 0, offset + 6)
|
|
|
|
offset += 8
|
|
ropt.encode(a.options || [], buf, offset)
|
|
offset += ropt.encode.bytes
|
|
} else {
|
|
let klass = classes.toClass(a.class === undefined ? 'IN' : a.class)
|
|
if (a.flush) klass |= FLUSH_MASK // the 1st bit of the class is the flush bit
|
|
buf.writeUInt16BE(klass, offset + 2)
|
|
buf.writeUInt32BE(a.ttl || 0, offset + 4)
|
|
|
|
offset += 8
|
|
const enc = renc(a.type)
|
|
enc.encode(a.data, buf, offset)
|
|
offset += enc.encode.bytes
|
|
}
|
|
|
|
answer.encode.bytes = offset - oldOffset
|
|
return buf
|
|
}
|
|
|
|
answer.encode.bytes = 0
|
|
|
|
answer.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
|
|
const a = {}
|
|
const oldOffset = offset
|
|
|
|
a.name = name.decode(buf, offset)
|
|
offset += name.decode.bytes
|
|
a.type = types.toString(buf.readUInt16BE(offset))
|
|
if (a.type === 'OPT') {
|
|
a.udpPayloadSize = buf.readUInt16BE(offset + 2)
|
|
a.extendedRcode = buf.readUInt8(offset + 4)
|
|
a.ednsVersion = buf.readUInt8(offset + 5)
|
|
a.flags = buf.readUInt16BE(offset + 6)
|
|
a.flag_do = ((a.flags >> 15) & 0x1) === 1
|
|
a.options = ropt.decode(buf, offset + 8)
|
|
offset += 8 + ropt.decode.bytes
|
|
} else {
|
|
const klass = buf.readUInt16BE(offset + 2)
|
|
a.ttl = buf.readUInt32BE(offset + 4)
|
|
|
|
a.class = classes.toString(klass & NOT_FLUSH_MASK)
|
|
a.flush = !!(klass & FLUSH_MASK)
|
|
|
|
const enc = renc(a.type)
|
|
a.data = enc.decode(buf, offset + 8)
|
|
offset += 8 + enc.decode.bytes
|
|
}
|
|
|
|
answer.decode.bytes = offset - oldOffset
|
|
return a
|
|
}
|
|
|
|
answer.decode.bytes = 0
|
|
|
|
answer.encodingLength = function (a) {
|
|
const data = (a.data !== null && a.data !== undefined) ? a.data : a.options
|
|
return name.encodingLength(a.name) + 8 + renc(a.type).encodingLength(data)
|
|
}
|
|
|
|
const question = exports.question = {}
|
|
|
|
question.encode = function (q, buf, offset) {
|
|
if (!buf) buf = Buffer.alloc(question.encodingLength(q))
|
|
if (!offset) offset = 0
|
|
|
|
const oldOffset = offset
|
|
|
|
name.encode(q.name, buf, offset)
|
|
offset += name.encode.bytes
|
|
|
|
buf.writeUInt16BE(types.toType(q.type), offset)
|
|
offset += 2
|
|
|
|
buf.writeUInt16BE(classes.toClass(q.class === undefined ? 'IN' : q.class), offset)
|
|
offset += 2
|
|
|
|
question.encode.bytes = offset - oldOffset
|
|
return q
|
|
}
|
|
|
|
question.encode.bytes = 0
|
|
|
|
question.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
|
|
const oldOffset = offset
|
|
const q = {}
|
|
|
|
q.name = name.decode(buf, offset)
|
|
offset += name.decode.bytes
|
|
|
|
q.type = types.toString(buf.readUInt16BE(offset))
|
|
offset += 2
|
|
|
|
q.class = classes.toString(buf.readUInt16BE(offset))
|
|
offset += 2
|
|
|
|
const qu = !!(q.class & QU_MASK)
|
|
if (qu) q.class &= NOT_QU_MASK
|
|
|
|
question.decode.bytes = offset - oldOffset
|
|
return q
|
|
}
|
|
|
|
question.decode.bytes = 0
|
|
|
|
question.encodingLength = function (q) {
|
|
return name.encodingLength(q.name) + 4
|
|
}
|
|
|
|
exports.AUTHORITATIVE_ANSWER = 1 << 10
|
|
exports.TRUNCATED_RESPONSE = 1 << 9
|
|
exports.RECURSION_DESIRED = 1 << 8
|
|
exports.RECURSION_AVAILABLE = 1 << 7
|
|
exports.AUTHENTIC_DATA = 1 << 5
|
|
exports.CHECKING_DISABLED = 1 << 4
|
|
exports.DNSSEC_OK = 1 << 15
|
|
|
|
exports.encode = function (result, buf, offset) {
|
|
const allocing = !buf
|
|
|
|
if (allocing) buf = Buffer.alloc(exports.encodingLength(result))
|
|
if (!offset) offset = 0
|
|
|
|
const oldOffset = offset
|
|
|
|
if (!result.questions) result.questions = []
|
|
if (!result.answers) result.answers = []
|
|
if (!result.authorities) result.authorities = []
|
|
if (!result.additionals) result.additionals = []
|
|
|
|
header.encode(result, buf, offset)
|
|
offset += header.encode.bytes
|
|
|
|
offset = encodeList(result.questions, question, buf, offset)
|
|
offset = encodeList(result.answers, answer, buf, offset)
|
|
offset = encodeList(result.authorities, answer, buf, offset)
|
|
offset = encodeList(result.additionals, answer, buf, offset)
|
|
|
|
exports.encode.bytes = offset - oldOffset
|
|
|
|
// just a quick sanity check
|
|
if (allocing && exports.encode.bytes !== buf.length) {
|
|
return buf.slice(0, exports.encode.bytes)
|
|
}
|
|
|
|
return buf
|
|
}
|
|
|
|
exports.encode.bytes = 0
|
|
|
|
exports.decode = function (buf, offset) {
|
|
if (!offset) offset = 0
|
|
|
|
const oldOffset = offset
|
|
const result = header.decode(buf, offset)
|
|
offset += header.decode.bytes
|
|
|
|
offset = decodeList(result.questions, question, buf, offset)
|
|
offset = decodeList(result.answers, answer, buf, offset)
|
|
offset = decodeList(result.authorities, answer, buf, offset)
|
|
offset = decodeList(result.additionals, answer, buf, offset)
|
|
|
|
exports.decode.bytes = offset - oldOffset
|
|
|
|
return result
|
|
}
|
|
|
|
exports.decode.bytes = 0
|
|
|
|
exports.encodingLength = function (result) {
|
|
return header.encodingLength(result) +
|
|
encodingLengthList(result.questions || [], question) +
|
|
encodingLengthList(result.answers || [], answer) +
|
|
encodingLengthList(result.authorities || [], answer) +
|
|
encodingLengthList(result.additionals || [], answer)
|
|
}
|
|
|
|
exports.streamEncode = function (result) {
|
|
const buf = exports.encode(result)
|
|
const sbuf = Buffer.alloc(2)
|
|
sbuf.writeUInt16BE(buf.byteLength)
|
|
const combine = Buffer.concat([sbuf, buf])
|
|
exports.streamEncode.bytes = combine.byteLength
|
|
return combine
|
|
}
|
|
|
|
exports.streamEncode.bytes = 0
|
|
|
|
exports.streamDecode = function (sbuf) {
|
|
const len = sbuf.readUInt16BE(0)
|
|
if (sbuf.byteLength < len + 2) {
|
|
// not enough data
|
|
return null
|
|
}
|
|
const result = exports.decode(sbuf.slice(2))
|
|
exports.streamDecode.bytes = exports.decode.bytes
|
|
return result
|
|
}
|
|
|
|
exports.streamDecode.bytes = 0
|
|
|
|
function encodingLengthList (list, enc) {
|
|
let len = 0
|
|
for (let i = 0; i < list.length; i++) len += enc.encodingLength(list[i])
|
|
return len
|
|
}
|
|
|
|
function encodeList (list, enc, buf, offset) {
|
|
for (let i = 0; i < list.length; i++) {
|
|
enc.encode(list[i], buf, offset)
|
|
offset += enc.encode.bytes
|
|
}
|
|
return offset
|
|
}
|
|
|
|
function decodeList (list, enc, buf, offset) {
|
|
for (let i = 0; i < list.length; i++) {
|
|
list[i] = enc.decode(buf, offset)
|
|
offset += enc.decode.bytes
|
|
}
|
|
return offset
|
|
}
|