1# proxy-addr
  2
  3[![NPM Version][npm-image]][npm-url]
  4[![NPM Downloads][downloads-image]][downloads-url]
  5[![Node.js Version][node-version-image]][node-version-url]
  6[![Build Status][travis-image]][travis-url]
  7[![Test Coverage][coveralls-image]][coveralls-url]
  8
  9Determine address of proxied request
 10
 11## Install
 12
 13```sh
 14$ npm install proxy-addr
 15```
 16
 17## API
 18
 19```js
 20var proxyaddr = require('proxy-addr')
 21```
 22
 23### proxyaddr(req, trust)
 24
 25Return the address of the request, using the given `trust` parameter.
 26
 27The `trust` argument is a function that returns `true` if you trust
 28the address, `false` if you don't. The closest untrusted address is
 29returned.
 30
 31```js
 32proxyaddr(req, function(addr){ return addr === '127.0.0.1' })
 33proxyaddr(req, function(addr, i){ return i < 1 })
 34```
 35
 36The `trust` arugment may also be a single IP address string or an
 37array of trusted addresses, as plain IP addresses, CIDR-formatted
 38strings, or IP/netmask strings.
 39
 40```js
 41proxyaddr(req, '127.0.0.1')
 42proxyaddr(req, ['127.0.0.0/8', '10.0.0.0/8'])
 43proxyaddr(req, ['127.0.0.0/255.0.0.0', '192.168.0.0/255.255.0.0'])
 44```
 45
 46This module also supports IPv6. Your IPv6 addresses will be normalized
 47automatically (i.e. `fe80::00ed:1` equals `fe80:0:0:0:0:0:ed:1`).
 48
 49```js
 50proxyaddr(req, '::1')
 51proxyaddr(req, ['::1/128', 'fe80::/10'])
 52proxyaddr(req, ['fe80::/ffc0::'])
 53```
 54
 55This module will automatically work with IPv4-mapped IPv6 addresses
 56as well to support node.js in IPv6-only mode. This means that you do
 57not have to specify both `::ffff:a00:1` and `10.0.0.1`.
 58
 59As a convenience, this module also takes certain pre-defined names
 60in addition to IP addresses, which expand into IP addresses:
 61
 62```js
 63proxyaddr(req, 'loopback')
 64proxyaddr(req, ['loopback', 'fc00:ac:1ab5:fff::1/64'])
 65```
 66
 67  * `loopback`: IPv4 and IPv6 loopback addresses (like `::1` and
 68    `127.0.0.1`).
 69  * `linklocal`: IPv4 and IPv6 link-local addresses (like
 70    `fe80::1:1:1:1` and `169.254.0.1`).
 71  * `uniquelocal`: IPv4 private addresses and IPv6 unique-local
 72    addresses (like `fc00:ac:1ab5:fff::1` and `192.168.0.1`).
 73
 74When `trust` is specified as a function, it will be called for each
 75address to determine if it is a trusted address. The function is
 76given two arguments: `addr` and `i`, where `addr` is a string of
 77the address to check and `i` is a number that represents the distance
 78from the socket address.
 79
 80### proxyaddr.all(req, [trust])
 81
 82Return all the addresses of the request, optionally stopping at the
 83first untrusted. This array is ordered from closest to furthest
 84(i.e. `arr[0] === req.connection.remoteAddress`).
 85
 86```js
 87proxyaddr.all(req)
 88```
 89
 90The optional `trust` argument takes the same arguments as `trust`
 91does in `proxyaddr(req, trust)`.
 92
 93```js
 94proxyaddr.all(req, 'loopback')
 95```
 96
 97### proxyaddr.compile(val)
 98
 99Compiles argument `val` into a `trust` function. This function takes
100the same arguments as `trust` does in `proxyaddr(req, trust)` and
101returns a function suitable for `proxyaddr(req, trust)`.
102
103```js
104var trust = proxyaddr.compile('localhost')
105var addr  = proxyaddr(req, trust)
106```
107
108This function is meant to be optimized for use against every request.
109It is recommend to compile a trust function up-front for the trusted
110configuration and pass that to `proxyaddr(req, trust)` for each request.
111
112## Testing
113
114```sh
115$ npm test
116```
117
118## Benchmarks
119
120```sh
121$ npm run-script bench
122```
123
124## License
125
126[MIT](LICENSE)
127
128[npm-image]: https://img.shields.io/npm/v/proxy-addr.svg
129[npm-url]: https://npmjs.org/package/proxy-addr
130[node-version-image]: https://img.shields.io/node/v/proxy-addr.svg
131[node-version-url]: http://nodejs.org/download/
132[travis-image]: https://img.shields.io/travis/jshttp/proxy-addr/master.svg
133[travis-url]: https://travis-ci.org/jshttp/proxy-addr
134[coveralls-image]: https://img.shields.io/coveralls/jshttp/proxy-addr/master.svg
135[coveralls-url]: https://coveralls.io/r/jshttp/proxy-addr?branch=master
136[downloads-image]: https://img.shields.io/npm/dm/proxy-addr.svg
137[downloads-url]: https://npmjs.org/package/proxy-addr