You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
234 lines
8.1 KiB
Markdown
234 lines
8.1 KiB
Markdown
# ipaddr.js — an IPv6 and IPv4 address manipulation library [](https://travis-ci.org/whitequark/ipaddr.js)
|
|
|
|
ipaddr.js is a small (1.9K minified and gzipped) library for manipulating
|
|
IP addresses in JavaScript environments. It runs on both CommonJS runtimes
|
|
(e.g. [nodejs]) and in a web browser.
|
|
|
|
ipaddr.js allows you to verify and parse string representation of an IP
|
|
address, match it against a CIDR range or range list, determine if it falls
|
|
into some reserved ranges (examples include loopback and private ranges),
|
|
and convert between IPv4 and IPv4-mapped IPv6 addresses.
|
|
|
|
[nodejs]: http://nodejs.org
|
|
|
|
## Installation
|
|
|
|
`npm install ipaddr.js`
|
|
|
|
or
|
|
|
|
`bower install ipaddr.js`
|
|
|
|
## API
|
|
|
|
ipaddr.js defines one object in the global scope: `ipaddr`. In CommonJS,
|
|
it is exported from the module:
|
|
|
|
```js
|
|
var ipaddr = require('ipaddr.js');
|
|
```
|
|
|
|
The API consists of several global methods and two classes: ipaddr.IPv6 and ipaddr.IPv4.
|
|
|
|
### Global methods
|
|
|
|
There are three global methods defined: `ipaddr.isValid`, `ipaddr.parse` and
|
|
`ipaddr.process`. All of them receive a string as a single parameter.
|
|
|
|
The `ipaddr.isValid` method returns `true` if the address is a valid IPv4 or
|
|
IPv6 address, and `false` otherwise. It does not throw any exceptions.
|
|
|
|
The `ipaddr.parse` method returns an object representing the IP address,
|
|
or throws an `Error` if the passed string is not a valid representation of an
|
|
IP address.
|
|
|
|
The `ipaddr.process` method works just like the `ipaddr.parse` one, but it
|
|
automatically converts IPv4-mapped IPv6 addresses to their IPv4 counterparts
|
|
before returning. It is useful when you have a Node.js instance listening
|
|
on an IPv6 socket, and the `net.ivp6.bindv6only` sysctl parameter (or its
|
|
equivalent on non-Linux OS) is set to 0. In this case, you can accept IPv4
|
|
connections on your IPv6-only socket, but the remote address will be mangled.
|
|
Use `ipaddr.process` method to automatically demangle it.
|
|
|
|
### Object representation
|
|
|
|
Parsing methods return an object which descends from `ipaddr.IPv6` or
|
|
`ipaddr.IPv4`. These objects share some properties, but most of them differ.
|
|
|
|
#### Shared properties
|
|
|
|
One can determine the type of address by calling `addr.kind()`. It will return
|
|
either `"ipv6"` or `"ipv4"`.
|
|
|
|
An address can be converted back to its string representation with `addr.toString()`.
|
|
Note that this method:
|
|
* does not return the original string used to create the object (in fact, there is
|
|
no way of getting that string)
|
|
* returns a compact representation (when it is applicable)
|
|
|
|
A `match(range, bits)` method can be used to check if the address falls into a
|
|
certain CIDR range.
|
|
Note that an address can be (obviously) matched only against an address of the same type.
|
|
|
|
For example:
|
|
|
|
```js
|
|
var addr = ipaddr.parse("2001:db8:1234::1");
|
|
var range = ipaddr.parse("2001:db8::");
|
|
|
|
addr.match(range, 32); // => true
|
|
```
|
|
|
|
Alternatively, `match` can also be called as `match([range, bits])`. In this way,
|
|
it can be used together with the `parseCIDR(string)` method, which parses an IP
|
|
address together with a CIDR range.
|
|
|
|
For example:
|
|
|
|
```js
|
|
var addr = ipaddr.parse("2001:db8:1234::1");
|
|
|
|
addr.match(ipaddr.parseCIDR("2001:db8::/32")); // => true
|
|
```
|
|
|
|
A `range()` method returns one of predefined names for several special ranges defined
|
|
by IP protocols. The exact names (and their respective CIDR ranges) can be looked up
|
|
in the source: [IPv6 ranges] and [IPv4 ranges]. Some common ones include `"unicast"`
|
|
(the default one) and `"reserved"`.
|
|
|
|
You can match against your own range list by using
|
|
`ipaddr.subnetMatch(address, rangeList, defaultName)` method. It can work with a mix of IPv6 or IPv4 addresses, and accepts a name-to-subnet map as the range list. For example:
|
|
|
|
```js
|
|
var rangeList = {
|
|
documentationOnly: [ ipaddr.parse('2001:db8::'), 32 ],
|
|
tunnelProviders: [
|
|
[ ipaddr.parse('2001:470::'), 32 ], // he.net
|
|
[ ipaddr.parse('2001:5c0::'), 32 ] // freenet6
|
|
]
|
|
};
|
|
ipaddr.subnetMatch(ipaddr.parse('2001:470:8:66::1'), rangeList, 'unknown'); // => "tunnelProviders"
|
|
```
|
|
|
|
The addresses can be converted to their byte representation with `toByteArray()`.
|
|
(Actually, JavaScript mostly does not know about byte buffers. They are emulated with
|
|
arrays of numbers, each in range of 0..255.)
|
|
|
|
```js
|
|
var bytes = ipaddr.parse('2a00:1450:8007::68').toByteArray(); // ipv6.google.com
|
|
bytes // => [42, 0x00, 0x14, 0x50, 0x80, 0x07, 0x00, <zeroes...>, 0x00, 0x68 ]
|
|
```
|
|
|
|
The `ipaddr.IPv4` and `ipaddr.IPv6` objects have some methods defined, too. All of them
|
|
have the same interface for both protocols, and are similar to global methods.
|
|
|
|
`ipaddr.IPvX.isValid(string)` can be used to check if the string is a valid address
|
|
for particular protocol, and `ipaddr.IPvX.parse(string)` is the error-throwing parser.
|
|
|
|
`ipaddr.IPvX.isValid(string)` uses the same format for parsing as the POSIX `inet_ntoa` function, which accepts unusual formats like `0xc0.168.1.1` or `0x10000000`. The function `ipaddr.IPv4.isValidFourPartDecimal(string)` validates the IPv4 address and also ensures that it is written in four-part decimal format.
|
|
|
|
[IPv6 ranges]: https://github.com/whitequark/ipaddr.js/blob/master/src/ipaddr.coffee#L186
|
|
[IPv4 ranges]: https://github.com/whitequark/ipaddr.js/blob/master/src/ipaddr.coffee#L71
|
|
|
|
#### IPv6 properties
|
|
|
|
Sometimes you will want to convert IPv6 not to a compact string representation (with
|
|
the `::` substitution); the `toNormalizedString()` method will return an address where
|
|
all zeroes are explicit.
|
|
|
|
For example:
|
|
|
|
```js
|
|
var addr = ipaddr.parse("2001:0db8::0001");
|
|
addr.toString(); // => "2001:db8::1"
|
|
addr.toNormalizedString(); // => "2001:db8:0:0:0:0:0:1"
|
|
```
|
|
|
|
The `isIPv4MappedAddress()` method will return `true` if this address is an IPv4-mapped
|
|
one, and `toIPv4Address()` will return an IPv4 object address.
|
|
|
|
To access the underlying binary representation of the address, use `addr.parts`.
|
|
|
|
```js
|
|
var addr = ipaddr.parse("2001:db8:10::1234:DEAD");
|
|
addr.parts // => [0x2001, 0xdb8, 0x10, 0, 0, 0, 0x1234, 0xdead]
|
|
```
|
|
|
|
A IPv6 zone index can be accessed via `addr.zoneId`:
|
|
|
|
```js
|
|
var addr = ipaddr.parse("2001:db8::%eth0");
|
|
addr.zoneId // => 'eth0'
|
|
```
|
|
|
|
#### IPv4 properties
|
|
|
|
`toIPv4MappedAddress()` will return a corresponding IPv4-mapped IPv6 address.
|
|
|
|
To access the underlying representation of the address, use `addr.octets`.
|
|
|
|
```js
|
|
var addr = ipaddr.parse("192.168.1.1");
|
|
addr.octets // => [192, 168, 1, 1]
|
|
```
|
|
|
|
`prefixLengthFromSubnetMask()` will return a CIDR prefix length for a valid IPv4 netmask or
|
|
false if the netmask is not valid.
|
|
|
|
```js
|
|
ipaddr.IPv4.parse('255.255.255.240').prefixLengthFromSubnetMask() == 28
|
|
ipaddr.IPv4.parse('255.192.164.0').prefixLengthFromSubnetMask() == null
|
|
```
|
|
|
|
`subnetMaskFromPrefixLength()` will return an IPv4 netmask for a valid CIDR prefix length.
|
|
|
|
```js
|
|
ipaddr.IPv4.subnetMaskFromPrefixLength(24) == "255.255.255.0"
|
|
ipaddr.IPv4.subnetMaskFromPrefixLength(29) == "255.255.255.248"
|
|
```
|
|
|
|
`broadcastAddressFromCIDR()` will return the broadcast address for a given IPv4 interface and netmask in CIDR notation.
|
|
```js
|
|
ipaddr.IPv4.broadcastAddressFromCIDR("172.0.0.1/24") == "172.0.0.255"
|
|
```
|
|
`networkAddressFromCIDR()` will return the network address for a given IPv4 interface and netmask in CIDR notation.
|
|
```js
|
|
ipaddr.IPv4.networkAddressFromCIDR("172.0.0.1/24") == "172.0.0.0"
|
|
```
|
|
|
|
#### Conversion
|
|
|
|
IPv4 and IPv6 can be converted bidirectionally to and from network byte order (MSB) byte arrays.
|
|
|
|
The `fromByteArray()` method will take an array and create an appropriate IPv4 or IPv6 object
|
|
if the input satisfies the requirements. For IPv4 it has to be an array of four 8-bit values,
|
|
while for IPv6 it has to be an array of sixteen 8-bit values.
|
|
|
|
For example:
|
|
```js
|
|
var addr = ipaddr.fromByteArray([0x7f, 0, 0, 1]);
|
|
addr.toString(); // => "127.0.0.1"
|
|
```
|
|
|
|
or
|
|
|
|
```js
|
|
var addr = ipaddr.fromByteArray([0x20, 1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1])
|
|
addr.toString(); // => "2001:db8::1"
|
|
```
|
|
|
|
Both objects also offer a `toByteArray()` method, which returns an array in network byte order (MSB).
|
|
|
|
For example:
|
|
```js
|
|
var addr = ipaddr.parse("127.0.0.1");
|
|
addr.toByteArray(); // => [0x7f, 0, 0, 1]
|
|
```
|
|
|
|
or
|
|
|
|
```js
|
|
var addr = ipaddr.parse("2001:db8::1");
|
|
addr.toByteArray(); // => [0x20, 1, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1]
|
|
```
|