opusdev/vector-similarity-api

1/*!2 * proxy-addr3 * Copyright(c) 2014-2016 Douglas Christopher Wilson4 * MIT Licensed5 */6 7'use strict'8 9/**10 * Module exports.11 * @public12 */13 14module.exports = proxyaddr15module.exports.all = alladdrs16module.exports.compile = compile17 18/**19 * Module dependencies.20 * @private21 */22 23var forwarded = require('forwarded')24var ipaddr = require('ipaddr.js')25 26/**27 * Variables.28 * @private29 */30 31var DIGIT_REGEXP = /^[0-9]+$/32var isip = ipaddr.isValid33var parseip = ipaddr.parse34 35/**36 * Pre-defined IP ranges.37 * @private38 */39 40var IP_RANGES = {41  linklocal: ['169.254.0.0/16', 'fe80::/10'],42  loopback: ['127.0.0.1/8', '::1/128'],43  uniquelocal: ['10.0.0.0/8', '172.16.0.0/12', '192.168.0.0/16', 'fc00::/7']44}45 46/**47 * Get all addresses in the request, optionally stopping48 * at the first untrusted.49 *50 * @param {Object} request51 * @param {Function|Array|String} [trust]52 * @public53 */54 55function alladdrs (req, trust) {56  // get addresses57  var addrs = forwarded(req)58 59  if (!trust) {60    // Return all addresses61    return addrs62  }63 64  if (typeof trust !== 'function') {65    trust = compile(trust)66  }67 68  for (var i = 0; i < addrs.length - 1; i++) {69    if (trust(addrs[i], i)) continue70 71    addrs.length = i + 172  }73 74  return addrs75}76 77/**78 * Compile argument into trust function.79 *80 * @param {Array|String} val81 * @private82 */83 84function compile (val) {85  if (!val) {86    throw new TypeError('argument is required')87  }88 89  var trust90 91  if (typeof val === 'string') {92    trust = [val]93  } else if (Array.isArray(val)) {94    trust = val.slice()95  } else {96    throw new TypeError('unsupported trust argument')97  }98 99  for (var i = 0; i < trust.length; i++) {100    val = trust[i]101 102    if (!Object.prototype.hasOwnProperty.call(IP_RANGES, val)) {103      continue104    }105 106    // Splice in pre-defined range107    val = IP_RANGES[val]108    trust.splice.apply(trust, [i, 1].concat(val))109    i += val.length - 1110  }111 112  return compileTrust(compileRangeSubnets(trust))113}114 115/**116 * Compile `arr` elements into range subnets.117 *118 * @param {Array} arr119 * @private120 */121 122function compileRangeSubnets (arr) {123  var rangeSubnets = new Array(arr.length)124 125  for (var i = 0; i < arr.length; i++) {126    rangeSubnets[i] = parseipNotation(arr[i])127  }128 129  return rangeSubnets130}131 132/**133 * Compile range subnet array into trust function.134 *135 * @param {Array} rangeSubnets136 * @private137 */138 139function compileTrust (rangeSubnets) {140  // Return optimized function based on length141  var len = rangeSubnets.length142  return len === 0143    ? trustNone144    : len === 1145      ? trustSingle(rangeSubnets[0])146      : trustMulti(rangeSubnets)147}148 149/**150 * Parse IP notation string into range subnet.151 *152 * @param {String} note153 * @private154 */155 156function parseipNotation (note) {157  var pos = note.lastIndexOf('/')158  var str = pos !== -1159    ? note.substring(0, pos)160    : note161 162  if (!isip(str)) {163    throw new TypeError('invalid IP address: ' + str)164  }165 166  var ip = parseip(str)167 168  if (pos === -1 && ip.kind() === 'ipv6' && ip.isIPv4MappedAddress()) {169    // Store as IPv4170    ip = ip.toIPv4Address()171  }172 173  var max = ip.kind() === 'ipv6'174    ? 128175    : 32176 177  var range = pos !== -1178    ? note.substring(pos + 1, note.length)179    : null180 181  if (range === null) {182    range = max183  } else if (DIGIT_REGEXP.test(range)) {184    range = parseInt(range, 10)185  } else if (ip.kind() === 'ipv4' && isip(range)) {186    range = parseNetmask(range)187  } else {188    range = null189  }190 191  if (range <= 0 || range > max) {192    throw new TypeError('invalid range on address: ' + note)193  }194 195  return [ip, range]196}197 198/**199 * Parse netmask string into CIDR range.200 *201 * @param {String} netmask202 * @private203 */204 205function parseNetmask (netmask) {206  var ip = parseip(netmask)207  var kind = ip.kind()208 209  return kind === 'ipv4'210    ? ip.prefixLengthFromSubnetMask()211    : null212}213 214/**215 * Determine address of proxied request.216 *217 * @param {Object} request218 * @param {Function|Array|String} trust219 * @public220 */221 222function proxyaddr (req, trust) {223  if (!req) {224    throw new TypeError('req argument is required')225  }226 227  if (!trust) {228    throw new TypeError('trust argument is required')229  }230 231  var addrs = alladdrs(req, trust)232  var addr = addrs[addrs.length - 1]233 234  return addr235}236 237/**238 * Static trust function to trust nothing.239 *240 * @private241 */242 243function trustNone () {244  return false245}246 247/**248 * Compile trust function for multiple subnets.249 *250 * @param {Array} subnets251 * @private252 */253 254function trustMulti (subnets) {255  return function trust (addr) {256    if (!isip(addr)) return false257 258    var ip = parseip(addr)259    var ipconv260    var kind = ip.kind()261 262    for (var i = 0; i < subnets.length; i++) {263      var subnet = subnets[i]264      var subnetip = subnet[0]265      var subnetkind = subnetip.kind()266      var subnetrange = subnet[1]267      var trusted = ip268 269      if (kind !== subnetkind) {270        if (subnetkind === 'ipv4' && !ip.isIPv4MappedAddress()) {271          // Incompatible IP addresses272          continue273        }274 275        if (!ipconv) {276          // Convert IP to match subnet IP kind277          ipconv = subnetkind === 'ipv4'278            ? ip.toIPv4Address()279            : ip.toIPv4MappedAddress()280        }281 282        trusted = ipconv283      }284 285      if (trusted.match(subnetip, subnetrange)) {286        return true287      }288    }289 290    return false291  }292}293 294/**295 * Compile trust function for single subnet.296 *297 * @param {Object} subnet298 * @private299 */300 301function trustSingle (subnet) {302  var subnetip = subnet[0]303  var subnetkind = subnetip.kind()304  var subnetisipv4 = subnetkind === 'ipv4'305  var subnetrange = subnet[1]306 307  return function trust (addr) {308    if (!isip(addr)) return false309 310    var ip = parseip(addr)311    var kind = ip.kind()312 313    if (kind !== subnetkind) {314      if (subnetisipv4 && !ip.isIPv4MappedAddress()) {315        // Incompatible IP addresses316        return false317      }318 319      // Convert IP to match subnet IP kind320      ip = subnetisipv4321        ? ip.toIPv4Address()322        : ip.toIPv4MappedAddress()323    }324 325    return ip.match(subnetip, subnetrange)326  }327}328