HORIZON PROJECT

# proxy-addr

[![NPM Version][npm-image]][npm-url]

[![NPM Downloads][downloads-image]][downloads-url]

[![Node.js Version][node-version-image]][node-version-url]

[![Build Status][travis-image]][travis-url]

[![Test Coverage][coveralls-image]][coveralls-url]

Determine address of proxied request

## Install

This is a [Node.js](https://nodejs.org/en/) module available through the

[npm registry](https://www.npmjs.com/). Installation is done using the

[`npm install` command](https://docs.npmjs.com/getting-started/installing-npm-packages-locally):

```sh

$ npm install proxy-addr

```

## API

<!-- eslint-disable no-unused-vars -->

```js

var proxyaddr = require('proxy-addr')

```

### proxyaddr(req, trust)

Return the address of the request, using the given `trust` parameter.

The `trust` argument is a function that returns `true` if you trust

the address, `false` if you don't. The closest untrusted address is

returned.

<!-- eslint-disable no-undef -->

```js

proxyaddr(req, function (addr) { return addr === '127.0.0.1' })

proxyaddr(req, function (addr, i) { return i < 1 })

```

The `trust` arugment may also be a single IP address string or an

array of trusted addresses, as plain IP addresses, CIDR-formatted

strings, or IP/netmask strings.

<!-- eslint-disable no-undef -->

```js

proxyaddr(req, '127.0.0.1')

proxyaddr(req, ['127.0.0.0/8', '10.0.0.0/8'])

proxyaddr(req, ['127.0.0.0/255.0.0.0', '192.168.0.0/255.255.0.0'])

```

This module also supports IPv6. Your IPv6 addresses will be normalized

automatically (i.e. `fe80::00ed:1` equals `fe80:0:0:0:0:0:ed:1`).

<!-- eslint-disable no-undef -->

```js

proxyaddr(req, '::1')

proxyaddr(req, ['::1/128', 'fe80::/10'])

```

This module will automatically work with IPv4-mapped IPv6 addresses

as well to support node.js in IPv6-only mode. This means that you do

not have to specify both `::ffff:a00:1` and `10.0.0.1`.

As a convenience, this module also takes certain pre-defined names

in addition to IP addresses, which expand into IP addresses:

<!-- eslint-disable no-undef -->

```js

proxyaddr(req, 'loopback')

proxyaddr(req, ['loopback', 'fc00:ac:1ab5:fff::1/64'])

```

  * `loopback`: IPv4 and IPv6 loopback addresses (like `::1` and

    `127.0.0.1`).

  * `linklocal`: IPv4 and IPv6 link-local addresses (like

    `fe80::1:1:1:1` and `169.254.0.1`).

  * `uniquelocal`: IPv4 private addresses and IPv6 unique-local

    addresses (like `fc00:ac:1ab5:fff::1` and `192.168.0.1`).

When `trust` is specified as a function, it will be called for each

address to determine if it is a trusted address. The function is

given two arguments: `addr` and `i`, where `addr` is a string of

the address to check and `i` is a number that represents the distance

from the socket address.

### proxyaddr.all(req, [trust])

Return all the addresses of the request, optionally stopping at the

first untrusted. This array is ordered from closest to furthest

(i.e. `arr[0] === req.connection.remoteAddress`).

<!-- eslint-disable no-undef -->

```js

proxyaddr.all(req)

```

The optional `trust` argument takes the same arguments as `trust`

does in `proxyaddr(req, trust)`.

<!-- eslint-disable no-undef -->

```js

proxyaddr.all(req, 'loopback')

```

### proxyaddr.compile(val)

Compiles argument `val` into a `trust` function. This function takes

the same arguments as `trust` does in `proxyaddr(req, trust)` and

returns a function suitable for `proxyaddr(req, trust)`.

<!-- eslint-disable no-undef, no-unused-vars -->

```js

var trust = proxyaddr.compile('localhost')

var addr = proxyaddr(req, trust)

```

This function is meant to be optimized for use against every request.

It is recommend to compile a trust function up-front for the trusted

configuration and pass that to `proxyaddr(req, trust)` for each request.

## Testing

```sh

$ npm test

```

## Benchmarks

```sh

$ npm run-script bench

```

## License

[MIT](LICENSE)

[npm-image]: https://img.shields.io/npm/v/proxy-addr.svg

[npm-url]: https://npmjs.org/package/proxy-addr

[node-version-image]: https://img.shields.io/node/v/proxy-addr.svg

[node-version-url]: https://nodejs.org/en/download/

[travis-image]: https://img.shields.io/travis/jshttp/proxy-addr/master.svg

[travis-url]: https://travis-ci.org/jshttp/proxy-addr

[coveralls-image]: https://img.shields.io/coveralls/jshttp/proxy-addr/master.svg

[coveralls-url]: https://coveralls.io/r/jshttp/proxy-addr?branch=master

[downloads-image]: https://img.shields.io/npm/dm/proxy-addr.svg

[downloads-url]: https://npmjs.org/package/proxy-addr