Module:IP
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Module:IP is a library for working with IP addresses and subnets. It can handle both IPv4 and IPv6. The library exports four classes, IPAddress, Subnet, IPv4Collection, and IPv6Collection.
Loading the library
local IP = require('Module:IP')
local IPAddress = IP.IPAddress
local Subnet = IP.Subnet
IPAddress
The IPAddress class is used to work with single IP addresses. To create a new IPAddress object:
local ipAddress = IPAddress.new(ipString)
The ipString variable can be a valid IPv4 or IPv6 address.
Examples:
local ipv4Address = IPAddress.new('1.2.3.4')
local ipv6Address = IPAddress.new('2001:db8::ff00:12:3456')
IPAddress objects can be compared with relational operators:
-- Equality
IPAddress.new('1.2.3.4') == IPAddress.new('1.2.3.4') -- true
IPAddress.new('1.2.3.4') == IPAddress.new('1.2.3.5') -- false
-- Less than / greater than
IPAddress.new('1.2.3.4') < IPAddress.new('1.2.3.5') -- true
IPAddress.new('1.2.3.4') > IPAddress.new('1.2.3.5') -- false
IPAddress.new('1.2.3.4') <= IPAddress.new('1.2.3.5') -- true
IPAddress.new('1.2.3.4') <= IPAddress.new('1.2.3.4') -- true
You can use tostring on them (this is equivalent to using getIP):
tostring(IPAddress.new('1.2.3.4')) -- "1.2.3.4"
tostring(IPAddress.new('2001:db8::ff00:12:3456')) -- "2001:db8::ff00:12:3456"
-- Expanded IPv6 addresses are abbreviated:
tostring(IPAddress.new('2001:db8:0:0:0:0:0:0')) -- "2001:db8::"
You can also concatenate them:
IPAddress.new('1.2.3.4') .. ' foo' -- "1.2.3.4 foo"
IPAddress.new('1.2.3.4') .. IPAddress.new('5.6.7.8') -- "1.2.3.45.6.7.8"
IPAddress objects have several methods, outlined below.
getIP
ipAddress:getIP()
Returns a string representation of the IP address. IPv6 addresses are abbreviated if possible.
Examples:
IPAddress.new('1.2.3.4'):getIP() -- "1.2.3.4"
IPAddress.new('2001:db8::ff00:12:3456'):getIP() -- "2001:db8::ff00:12:3456"
IPAddress.new('2001:db8:0:0:0:0:0:0'):getIP() -- "2001:db8::"
getVersion
ipAddress:getVersion()
Returns the version of the IP protocol being used. This is "IPv4" for IPv4 addresses, and "IPv6" for IPv6 addresses.
Examples:
IPAddress.new('1.2.3.4'):getVersion() -- "IPv4"
IPAddress.new('2001:db8::ff00:12:3456'):getVersion() -- "IPv6"
isIPv4
ipAddress:isIPv4()
Returns true if the IP address is an IPv4 address, and false otherwise.
Examples:
IPAddress.new('1.2.3.4'):isIPv4() -- true
IPAddress.new('2001:db8::ff00:12:3456'):isIPv4() -- false
isIPv6
ipAddress:isIPv6()
Returns true if the IP address is an IPv6 address, and false otherwise.
Examples:
IPAddress.new('1.2.3.4'):isIPv6() -- false
IPAddress.new('2001:db8::ff00:12:3456'):isIPv6() -- true
isInSubnet
ipAddress:isInSubnet(subnet)
Returns true if the IP address is in the subnet subnet, and false otherwise. subnet may be a Subnet object or a CIDR string.
Examples:
IPAddress.new('1.2.3.4'):isInSubnet('1.2.3.0/24') -- true
IPAddress.new('1.2.3.4'):isInSubnet('1.2.4.0/24') -- false
IPAddress.new('1.2.3.4'):isInSubnet(Subnet.new('1.2.3.0/24')) -- true
IPAddress.new('2001:db8::ff00:12:3456'):isInSubnet('2001:db8::ff00:12:0/112') -- true
getSubnet
ipAddress:getSubnet(bitLength)
Returns a Subnet object for the subnet with a bit length of bitLength which contains the current IP. The bitLength parameter must be an integer between 0 and 32 for IPv4 addresses, or an integer between 0 and 128 for IPv6 addresses.
Examples:
IPAddress.new('1.2.3.4'):getSubnet(24) -- Equivalent to Subnet.new('1.2.3.0/24')
getNextIP
ipAddress:getNextIP()
Returns a new IPAddress object equivalent to the current IP address incremented by one. The IPv4 address "255.255.255.255" rolls around to "0.0.0.0", and the IPv6 address "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff" rolls around to "::".
Examples:
IPAddress.new('1.2.3.4'):getNextIP() -- Equivalent to IPAddress.new('1.2.3.5')
IPAddress.new('2001:db8::ff00:12:3456'):getNextIP() -- Equivalent to IPAddress.new('2001:db8::ff00:12:3457')
IPAddress.new('255.255.255.255'):getNextIP() -- Equivalent to IPAddress.new('0.0.0.0')
getPreviousIP
ipAddress:getPreviousIP()
Returns a new IPAddress object equivalent to the current IP address decremented by one. The IPv4 address "0.0.0.0" rolls around to "255.255.255.255", and the IPv6 address "::" rolls around to "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff".
Examples:
IPAddress.new('1.2.3.4'):getPreviousIP() -- Equivalent to IPAddress.new('1.2.3.3')
IPAddress.new('2001:db8::ff00:12:3456'):getPreviousIP() -- Equivalent to IPAddress.new('2001:db8::ff00:12:3455')
IPAddress.new('0.0.0.0'):getPreviousIP() -- Equivalent to IPAddress.new('255.255.255.255')
Subnet
The Subnet class is used to work with subnetworks of IPv4 or IPv6 addresses. To create a new Subnet object:
local subnet = Subnet.new(cidrString)
cidrString must be a valid IPv4 or IPv6 CIDR string.
Subnet objects can be compared for equality:
Subnet.new('1.2.3.0/24') == Subnet.new('1.2.3.0/24') -- true
Subnet.new('1.2.3.0/24') == Subnet.new('1.2.3.0/25') -- false
Subnet.new('1.2.3.0/24') == Subnet.new('2001:db8::ff00:12:0/112') -- false
Subnet.new('2001:db8::ff00:12:0/112') == Subnet.new('2001:db8::ff00:12:0/112') -- true
Subnet.new('2001:db8:0:0:0:0:0:0/112') == Subnet.new('2001:db8::/112') -- true
You can use tostring on them (this is equivalent to getCIDR):
tostring(Subnet.new('1.2.3.0/24')) -- "1.2.3.0/24"
tostring(Subnet.new('2001:db8::ff00:12:0/112')) -- "2001:db8::ff00:12:0/112"
tostring(Subnet.new('2001:db8:0:0:0:0:0:0/112')) -- "2001:db8::/112"
You can also concatenate them:
Subnet.new('1.2.3.0/24') .. ' foo' -- "1.2.3.0/24 foo"
Subnet.new('1.2.3.0/24') .. Subnet.new('4.5.6.0/24') -- "1.2.3.0/244.5.6.0/24"
Subnet objects have several methods, outlined below.
getPrefix
subnet:getPrefix()
Returns an IPAddress object for the lowest IP address in the subnet.
Examples:
Subnet.new('1.2.3.0/24'):getPrefix() -- Equivalent to IPAddress.new('1.2.3.0')
Subnet.new('2001:db8::ff00:12:0/112'):getPrefix() -- Equivalent to IPAddress.new('2001:db8::ff00:12:0')
getHighestIP
subnet:getHighestIP()
Returns an IPAddress object for the highest IP address in the subnet.
Examples:
Subnet.new('1.2.3.0/24'):getHighestIP() -- Equivalent to IPAddress.new('1.2.3.255')
Subnet.new('2001:db8::ff00:12:0/112'):getHighestIP() -- Equivalent to IPAddress.new('2001:db8::ff00:12:ffff')
getBitLength
subnet:getBitLength()
Returns the bit length of the subnet. This is an integer between 0 and 32 for IPv4 addresses, or an integer between 0 and 128 for IPv6 addresses.
Examples:
Subnet.new('1.2.3.0/24'):getBitLength() -- 24
Subnet.new('2001:db8::ff00:12:0/112'):getBitLength() -- 112
getCIDR
subnet:getCIDR()
Returns a CIDR string representation of the subnet.
Examples:
Subnet.new('1.2.3.0/24'):getCIDR() -- "1.2.3.0/24"
Subnet.new('2001:db8::ff00:12:0/112'):getCIDR() -- "2001:db8::ff00:12:0/112"
Subnet.new('2001:db8:0:0:0:0:0:0/112'):getCIDR() -- "2001:db8::/112"
getVersion
subnet:getVersion()
Returns the version of the IP protocol being used. This is "IPv4" for IPv4 addresses, and "IPv6" for IPv6 addresses.
Examples:
Subnet.new('1.2.3.0/24'):getVersion() -- "IPv4"
Subnet.new('2001:db8::ff00:12:0/112'):getVersion() -- "IPv6"
isIPv4
subnet:isIPv4()
Returns true if the subnet is using IPv4, and false otherwise.
Examples:
Subnet.new('1.2.3.0/24'):isIPv4() -- true
Subnet.new('2001:db8::ff00:12:0/112'):isIPv4() -- false
isIPv6
subnet:isIPv6()
Returns true if the subnet is using IPv6, and false otherwise.
Examples:
Subnet.new('1.2.3.0/24'):isIPv6() -- false
Subnet.new('2001:db8::ff00:12:0/112'):isIPv6() -- true
containsIP
subnet:containsIP(ip)
Returns true if the subnet contains the IP address ip, and false otherwise. ip can be an IP address string, or an IPAddress object.
Examples:
Subnet.new('1.2.3.0/24'):containsIP('1.2.3.4') -- true
Subnet.new('1.2.3.0/24'):containsIP('1.2.4.4') -- false
Subnet.new('1.2.3.0/24'):containsIP(IPAddress.new('1.2.3.4')) -- true
Subnet.new('2001:db8::ff00:12:0/112'):containsIP('2001:db8::ff00:12:3456') -- true
overlapsSubnet
subnet:overlapsSubnet(subnet)
Returns true if the current subnet overlaps with subnet, and false otherwise. subnet can be a CIDR string or a subnet object.
Examples:
Subnet.new('1.2.3.0/24'):overlapsSubnet('1.2.0.0/16') -- true
Subnet.new('1.2.3.0/24'):overlapsSubnet('1.2.12.0/22') -- false
Subnet.new('1.2.3.0/24'):overlapsSubnet(Subnet.new('1.2.0.0/16')) -- true
Subnet.new('2001:db8::ff00:12:0/112'):overlapsSubnet('2001:db8::ff00:0:0/96') -- true
walk
subnet:walk()
The walk method iterates over all of the IPAddress objects in the subnet.
Examples:
for ipAddress in Subnet.new('192.168.0.0/30'):walk() do
mw.log(tostring(ipAddress))
end
-- 192.168.0.0
-- 192.168.0.1
-- 192.168.0.2
-- 192.168.0.3
IPv4Collection
The IPv4Collection class is used to work with several different IPv4 addresses and IPv4 subnets. To create a new IPv4Collection object:
local collection = IPv4Collection.new()
IPv4Collection objects have several methods, outlined below.
getVersion
collection:getVersion()
Returns the string "IPv4".
addIP
collection:addIP(ip)
Adds an IP to the collection. The IP can be either a string or an IPAddress object.
Examples:
collection:addIP('1.2.3.4')
collection:addIP(IPAddress.new('1.2.3.4'))
This method is chainable:
collection:addIP('1.2.3.4'):addIP('5.6.7.8')
addSubnet
collection:addSubnet(subnet)
Adds a subnet to the collection. The subnet can be either a CIDR string or a Subnet object.
Examples:
collection:addSubnet('1.2.3.0/24')
collection:addSubnet(Subnet.new('1.2.3.0/24'))
This method is chainable:
collection:addSubnet('1.2.0.0/24'):addSubnet('1.2.1.0/24')
addFromString
collection:addFromString(str)
Extracts any IPv4 addresses and IPv4 CIDR subnets from str and adds them to the collection. Any text that is not an IPv4 address or CIDR subnet is ignored.
Examples:
collection:addFromString('Add some IPs and subnets: 1.2.3.4 1.2.3.5 2001:0::f foo 1.2.4.0/24')
This method is chainable:
collection:addFromString('foo 1.2.3.4'):addFromString('bar 5.6.7.8')
containsIP
collection:containsIP(ip)
Returns true if the collection contains the specified IP; otherwise returns false. The ip parameter can be a string or an IPAddress object.
Examples:
collection:containsIP('1.2.3.4')
collection:containsIP(IPAddress.new('1.2.3.4'))
getRanges
collection:getRanges()
Returns a sorted array of IP pairs equivalent to the collection. Each IP pair is an array representing a contiguous range of IP addresses from pair[1] to pair[2] inclusive. pair[1] and pair[2] are IPAddress objects.
Examples:
collection:addSubnet('1.2.0.0/24')
collection:addSubnet('1.2.1.0/24')
collection:addSubnet('1.2.10.0/24')
mw.logObject(collection:getRanges())
-- Logs the following:
-- table#1 {
-- table#2 {
-- 1.2.0.0,
-- 1.2.1.255,
-- },
-- table#3 {
-- 1.2.10.0,
-- 1.2.10.255,
-- },
-- }
overlapsSubnet
collection:overlapsSubnet(subnet)
Returns true, obj if subnet overlaps this collection, where obj is the first IPAddress or Subnet object overlapping the subnet. Otherwise, returns false. subnet can be a CIDR string or a Subnet object.
Examples:
collection:addIP('1.2.3.4')
collection:overlapsSubnet('1.2.3.0/24') -- true, IPAddress.new('1.2.3.4')
collection:overlapsSubnet('1.2.4.0/24') -- false
IPv6Collection
The IPv6Collection class is used to work with several different IPv6 addresses and IPv6 subnets. IPv6Collection objects are directly analogous to IPv4Collection objects: they contain the same methods and work the same way, but all IP addresses and subnets added to it must be IPv6, not IPv4.
To create a new IPv6Collection object:
local collection = IPv6Collection.new()
-- IP library
-- This library contains classes for working with IP addresses and IP ranges.
-- Load modules
require('Module:No globals')
local bit32 = require('bit32')
local libraryUtil = require('libraryUtil')
local checkType = libraryUtil.checkType
local checkTypeMulti = libraryUtil.checkTypeMulti
local makeCheckSelfFunction = libraryUtil.makeCheckSelfFunction
-- Constants
local V4 = 'IPv4'
local V6 = 'IPv6'
--------------------------------------------------------------------------------
-- Helper functions
--------------------------------------------------------------------------------
local function makeValidationFunction(className, isObjectFunc)
-- Make a function for validating a specific object.
return function (methodName, argIdx, arg)
if not isObjectFunc(arg) then
error(string.format(
"bad argument #%d to '%s' (not a valid %s object)",
argIdx, methodName, className
), 3)
end
end
end
--------------------------------------------------------------------------------
-- RawIP class
-- Numeric representation of an IPv4 or IPv6 address. Used internally.
-- A RawIP object is constructed by adding data to a Collection object and
-- then giving it a new metatable. This is to avoid the memory overhead of
-- copying the data to a new table.
--------------------------------------------------------------------------------
local RawIP = {}
RawIP.__index = RawIP
do
-- Collection class.
-- This is a table used to hold items.
local Collection
do
local mt = {
__index = {
add = function (self, item)
self.n = self.n + 1
self[self.n] = item
end,
join = function (self, sep)
return table.concat(self, sep)
end,
}
}
Collection = function ()
return setmetatable({n = 0}, mt)
end
end
-- Constructors
function RawIP.newFromIPv4(ipStr)
-- Return a RawIP object if ipStr is a valid IPv4 string. Otherwise,
-- return nil.
-- This representation is for compatibility with IPv6 addresses.
local octets = Collection()
local s = ipStr:match('^%s*(.-)%s*$') .. '.'
for item in s:gmatch('(.-)%.') do
octets:add(item)
end
if octets.n == 4 then
for i, s in ipairs(octets) do
if s:match('^%d+$') then
local num = tonumber(s)
if 0 <= num and num <= 255 then
if num > 0 and s:match('^0') then
-- A redundant leading zero is for an IP in octal.
return nil
end
octets[i] = num
else
return nil
end
else
return nil
end
end
local parts = Collection()
for i = 1, 3, 2 do
parts:add(octets[i] * 256 + octets[i+1])
end
return setmetatable(parts, RawIP)
end
return nil
end
function RawIP.newFromIPv6(ipStr)
-- Return a RawIP object if ipStr is a valid IPv6 string. Otherwise,
-- return nil.
ipStr = ipStr:match('^%s*(.-)%s*$')
local _, n = ipStr:gsub(':', ':')
if n < 7 then
ipStr, n = ipStr:gsub('::', string.rep(':', 9 - n))
end
local parts = Collection()
for item in (ipStr .. ':'):gmatch('(.-):') do
parts:add(item)
end
if parts.n == 8 then
for i, s in ipairs(parts) do
if s == '' then
parts[i] = 0
else
local num = tonumber(s, 16)
if num and 0 <= num and num <= 65535 then
parts[i] = num
else
return nil
end
end
end
return setmetatable(parts, RawIP)
end
return nil
end
function RawIP.newFromIP(ipStr)
-- Return a new RawIP object from either an IPv4 string or an IPv6
-- string. If ipStr is not a valid IPv4 or IPv6 string, then return
-- nil.
return RawIP.newFromIPv4(ipStr) or RawIP.newFromIPv6(ipStr)
end
-- Methods
function RawIP:getVersion()
-- Return a string with the version of the IP protocol we are using.
return self.n == 2 and V4 or V6
end
function RawIP:isIPv4()
-- Return true if this is an IPv4 representation, and false otherwise.
return self.n == 2
end
function RawIP:isIPv6()
-- Return true if this is an IPv6 representation, and false otherwise.
return self.n == 8
end
function RawIP:getAdjacent(previous)
-- Return a RawIP object for an adjacent IP address. If previous is true
-- then the previous IP is returned; otherwise the next IP is returned.
-- Will wraparound:
-- next 255.255.255.255 → 0.0.0.0
-- ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff → ::
-- previous 0.0.0.0 → 255.255.255.255
-- :: → ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff
local result = Collection()
result.n = self.n
local carry = previous and 0xffff or 1
for i = self.n, 1, -1 do
local sum = self[i] + carry
if sum >= 0x10000 then
carry = previous and 0x10000 or 1
sum = sum - 0x10000
else
carry = previous and 0xffff or 0
end
result[i] = sum
end
return setmetatable(result, RawIP)
end
function RawIP:getPrefix(bitLength)
-- Return a RawIP object for the prefix of the current IP Address with a
-- bit length of bitLength.
local result = Collection()
result.n = self.n
for i = 1, self.n do
if bitLength > 0 then
if bitLength >= 16 then
result[i] = self[i]
bitLength = bitLength - 16
else
result[i] = bit32.replace(self[i], 0, 0, 16 - bitLength)
bitLength = 0
end
else
result[i] = 0
end
end
return setmetatable(result, RawIP)
end
function RawIP:getHighestHost(bitLength)
-- Return a RawIP object for the highest IP with the prefix of length
-- bitLength. In other words, the network (the most-significant bits)
-- is the same as the current IP's, but the host bits (the
-- least-significant bits) are all set to 1.
local bits = self.n * 16
local width
if bitLength <= 0 then
width = bits
elseif bitLength >= bits then
width = 0
else
width = bits - bitLength
end
local result = Collection()
result.n = self.n
for i = self.n, 1, -1 do
if width > 0 then
if width >= 16 then
result[i] = 0xffff
width = width - 16
else
result[i] = bit32.replace(self[i], 0xffff, 0, width)
width = 0
end
else
result[i] = self[i]
end
end
return setmetatable(result, RawIP)
end
function RawIP:_makeIPv6String()
-- Return an IPv6 string representation of the object. Behavior is
-- undefined if the current object is IPv4.
local z1, z2 -- indices of run of zeros to be displayed as "::"
local zstart, zcount
for i = 1, 9 do
-- Find left-most occurrence of longest run of two or more zeros.
if i < 9 and self[i] == 0 then
if zstart then
zcount = zcount + 1
else
zstart = i
zcount = 1
end
else
if zcount and zcount > 1 then
if not z1 or zcount > z2 - z1 + 1 then
z1 = zstart
z2 = zstart + zcount - 1
end
end
zstart = nil
zcount = nil
end
end
local parts = Collection()
for i = 1, 8 do
if z1 and z1 <= i and i <= z2 then
if i == z1 then
if z1 == 1 or z2 == 8 then
if z1 == 1 and z2 == 8 then
return '::'
end
parts:add(':')
else
parts:add('')
end
end
else
parts:add(string.format('%x', self[i]))
end
end
return parts:join(':')
end
function RawIP:_makeIPv4String()
-- Return an IPv4 string representation of the object. Behavior is
-- undefined if the current object is IPv6.
local parts = Collection()
for i = 1, 2 do
local w = self[i]
parts:add(math.floor(w / 256))
parts:add(w % 256)
end
return parts:join('.')
end
function RawIP:__tostring()
-- Return a string equivalent to given IP address (IPv4 or IPv6).
if self.n == 2 then
return self:_makeIPv4String()
else
return self:_makeIPv6String()
end
end
function RawIP:__lt(obj)
if self.n == obj.n then
for i = 1, self.n do
if self[i] ~= obj[i] then
return self[i] < obj[i]
end
end
return false
end
return self.n < obj.n
end
function RawIP:__eq(obj)
if self.n == obj.n then
for i = 1, self.n do
if self[i] ~= obj[i] then
return false
end
end
return true
end
return false
end
end
--------------------------------------------------------------------------------
-- Initialize private methods available to IPAddress and Subnet
--------------------------------------------------------------------------------
-- Both IPAddress and Subnet need access to each others' private constructor
-- functions. IPAddress must be able to make Subnet objects from CIDR strings
-- and from RawIP objects, and Subnet must be able to make IPAddress objects
-- from IP strings and from RawIP objects. These constructors must all be
-- private to ensure correct error levels and to stop other modules from having
-- to worry about RawIP objects. Because they are private, they must be
-- initialized here.
local makeIPAddress, makeIPAddressFromRaw, makeSubnet, makeSubnetFromRaw
-- IPAddress and Subnet also need to be able to validate Subnet and IPAddress
-- objects that they are passed as input, so initialize those functions here
-- as well.
local validateIPAddress, validateSubnet
--------------------------------------------------------------------------------
-- IPAddress class
-- Represents a single IPv4 or IPv6 address.
--------------------------------------------------------------------------------
local IPAddress = {}
do
-- dataKey is a unique key to access objects' internal data. This is needed
-- to access the RawIP objects contained in other IPAddress objects so that
-- they can be compared with the current object's RawIP object. This data
-- is not available to other classes or other modules.
local dataKey = {}
-- Private static methods
local function isIPAddressObject(val)
return type(val) == 'table' and val[dataKey] ~= nil
end
validateIPAddress = makeValidationFunction('IPAddress', isIPAddressObject)
-- Metamethods that don't need upvalues
local function ipEquals(ip1, ip2)
return ip1[dataKey].rawIP == ip2[dataKey].rawIP
end
local function ipLessThan(ip1, ip2)
return ip1[dataKey].rawIP < ip2[dataKey].rawIP
end
local function concatIP(ip, val)
return tostring(ip) .. tostring(val)
end
local function ipToString(ip)
return ip:getIP()
end
-- Constructors
makeIPAddressFromRaw = function (rawIP)
-- Constructs a new IPAddress object from a rawIP object. This function
-- is for internal use; it is called by IPAddress.new and from other
-- IPAddress methods, and should be available to the Subnet class, but
-- should not be available to other modules.
assert(type(rawIP) == 'table', 'rawIP was type ' .. type(rawIP) .. '; expected type table')
-- Set up structure
local obj = {}
local data = {}
data.rawIP = rawIP
-- A function to check whether methods are called with a valid self
-- parameter.
local checkSelf = makeCheckSelfFunction(
'IP',
'ipAddress',
obj,
'IPAddress object'
)
-- Public methods
function obj:getIP()
checkSelf(self, 'getIP')
return tostring(data.rawIP)
end
function obj:getVersion()
checkSelf(self, 'getVersion')
return data.rawIP:getVersion()
end
function obj:isIPv4()
checkSelf(self, 'isIPv4')
return data.rawIP:isIPv4()
end
function obj:isIPv6()
checkSelf(self, 'isIPv6')
return data.rawIP:isIPv6()
end
function obj:isInSubnet(subnet)
checkSelf(self, 'isInSubnet')
local tp = type(subnet)
if tp == 'string' then
subnet = makeSubnet(subnet)
elseif tp == 'table' then
validateSubnet('isInSubnet', 1, subnet)
else
checkTypeMulti('isInSubnet', 1, subnet, {'string', 'table'})
end
return subnet:containsIP(self)
end
function obj:getSubnet(bitLength)
checkSelf(self, 'getSubnet')
checkType('getSubnet', 1, bitLength, 'number')
return makeSubnetFromRaw(data.rawIP, bitLength)
end
function obj:getNextIP()
checkSelf(self, 'getNextIP')
return makeIPAddressFromRaw(data.rawIP:getAdjacent())
end
function obj:getPreviousIP()
checkSelf(self, 'getPreviousIP')
return makeIPAddressFromRaw(data.rawIP:getAdjacent(true))
end
-- Metamethods
return setmetatable(obj, {
__eq = ipEquals,
__lt = ipLessThan,
__concat = concatIP,
__tostring = ipToString,
__index = function (self, key)
-- If any code knows the unique data key, allow it to access
-- the data table.
if key == dataKey then
return data
end
end,
__metatable = false, -- Don't allow access to the metatable
})
end
makeIPAddress = function (ip)
local rawIP = RawIP.newFromIP(ip)
if not rawIP then
error(string.format("'%s' is an invalid IP address", ip), 3)
end
return makeIPAddressFromRaw(rawIP)
end
function IPAddress.new(ip)
checkType('IPAddress.new', 1, ip, 'string')
return makeIPAddress(ip)
end
end
--------------------------------------------------------------------------------
-- Subnet class
-- Represents a block of IPv4 or IPv6 addresses.
--------------------------------------------------------------------------------
local Subnet = {}
do
-- uniqueKey is a unique, private key used to test whether a given object
-- is a Subnet object.
local uniqueKey = setmetatable({}, {__metatable = false})
-- Private static methods
local function isSubnetObject(val)
-- Return true if val is a Subnet object, and false otherwise.
return getmetatable(val) == uniqueKey
end
-- Function to validate subnet objects.
-- Params:
-- methodName (string) - the name of the method being validated
-- argIdx (number) - the position of the argument in the argument list
-- arg - the argument to be validated
validateSubnet = makeValidationFunction('Subnet', isSubnetObject)
-- Metamethods that don't need upvalues
local function subnetEquals(subnet1, subnet2)
return subnet1:getCIDR() == subnet2:getCIDR()
end
local function concatenateSubnets(subnet1, subnet2)
return tostring(subnet1) .. tostring(subnet2)
end
local function subnetToString(subnet)
return subnet:getCIDR()
end
-- Constructors
makeSubnetFromRaw = function (rawIP, bitLength)
-- Set up structure
local obj = {}
local data = {
rawIP = rawIP,
bitLength = bitLength,
}
-- A function to check whether methods are called with a valid self
-- parameter.
local checkSelf = makeCheckSelfFunction(
'IP',
'subnet',
obj,
'Subnet object'
)
-- Public methods
function obj:getPrefix()
checkSelf(self, 'getPrefix')
if not data.prefix then
data.prefix = makeIPAddressFromRaw(
data.rawIP:getPrefix(data.bitLength)
)
end
return data.prefix
end
function obj:getHighestIP()
checkSelf(self, 'getHighestIP')
if not data.highestIP then
data.highestIP = makeIPAddressFromRaw(
data.rawIP:getHighestHost(data.bitLength)
)
end
return data.highestIP
end
function obj:getBitLength()
checkSelf(self, 'getBitLength')
return data.bitLength
end
function obj:getCIDR()
checkSelf(self, 'getCIDR')
return string.format(
'%s/%d',
tostring(self:getPrefix()), self:getBitLength()
)
end
function obj:getVersion()
checkSelf(self, 'getVersion')
return data.rawIP:getVersion()
end
function obj:isIPv4()
checkSelf(self, 'isIPv4')
return data.rawIP:isIPv4()
end
function obj:isIPv6()
checkSelf(self, 'isIPv6')
return data.rawIP:isIPv6()
end
function obj:containsIP(ip)
checkSelf(self, 'containsIP')
local tp = type(ip)
if tp == 'string' then
ip = makeIPAddress(ip)
elseif tp == 'table' then
validateIPAddress('containsIP', 1, ip)
else
checkTypeMulti('containsIP', 1, ip, {'string', 'table'})
end
if self:getVersion() == ip:getVersion() then
return self:getPrefix() <= ip and ip <= self:getHighestIP()
end
return false
end
function obj:overlapsSubnet(subnet)
checkSelf(self, 'overlapsSubnet')
local tp = type(subnet)
if tp == 'string' then
subnet = makeSubnet(subnet)
elseif tp == 'table' then
validateSubnet('overlapsSubnet', 1, subnet)
else
checkTypeMulti('overlapsSubnet', 1, subnet, {'string', 'table'})
end
if self:getVersion() == subnet:getVersion() then
return (
subnet:getHighestIP() >= self:getPrefix() and
subnet:getPrefix() <= self:getHighestIP()
)
end
return false
end
function obj:walk()
checkSelf(self, 'walk')
local started
local current = self:getPrefix()
local highest = self:getHighestIP()
return function ()
if not started then
started = true
return current
end
if current < highest then
current = current:getNextIP()
return current
end
end
end
return setmetatable(obj, {
__index = function (self, key)
if key == uniqueKey then
return true
end
end,
__eq = subnetEquals,
__concat = concatenateSubnets,
__tostring = subnetToString,
__metatable = false,
})
end
makeSubnet = function (cidr)
-- Return a Subnet object from a CIDR string. If the CIDR string is
-- invalid, throw an error.
local lhs, rhs = cidr:match('^%s*(.-)/(%d+)%s*$')
if lhs then
local bits = lhs:find(':', 1, true) and 128 or 32
local n = tonumber(rhs)
if n and n <= bits and (n == 0 or not rhs:find('^0')) then
-- The right-hand side is a number between 0 and 32 (for IPv4)
-- or 0 and 128 (for IPv6) and doesn't have any leading zeroes.
local base = RawIP.newFromIP(lhs)
if base then
-- The left-hand side is a valid IP address.
local prefix = base:getPrefix(n)
if base == prefix then
-- The left-hand side is the lowest IP in the subnet.
return makeSubnetFromRaw(prefix, n)
end
end
end
end
error(string.format("'%s' is an invalid CIDR string", cidr), 3)
end
function Subnet.new(cidr)
checkType('Subnet.new', 1, cidr, 'string')
return makeSubnet(cidr)
end
end
return {
IPAddress = IPAddress,
Subnet = Subnet,
}
