+++ /dev/null
---[[
-
-LuCI ip calculation libarary
-(c) 2008 Jo-Philipp Wich <xm@leipzig.freifunk.net>
-(c) 2008 Steven Barth <steven@midlink.org>
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
- http://www.apache.org/licenses/LICENSE-2.0
-
-$Id$
-
-]]--
-
---- LuCI IP calculation library.
-module( "luci.ip", package.seeall )
-
-require "nixio"
-local bit = nixio.bit
-local util = require "luci.util"
-
---- Boolean; true if system is little endian
-LITTLE_ENDIAN = not util.bigendian()
-
---- Boolean; true if system is big endian
-BIG_ENDIAN = not LITTLE_ENDIAN
-
---- Specifier for IPv4 address family
-FAMILY_INET4 = 0x04
-
---- Specifier for IPv6 address family
-FAMILY_INET6 = 0x06
-
-
-local function __bless(x)
- return setmetatable( x, {
- __index = luci.ip.cidr,
- __add = luci.ip.cidr.add,
- __sub = luci.ip.cidr.sub,
- __lt = luci.ip.cidr.lower,
- __eq = luci.ip.cidr.equal,
- __le =
- function(...)
- return luci.ip.cidr.equal(...) or luci.ip.cidr.lower(...)
- end
- } )
-end
-
-local function __array16( x, family )
- local list
-
- if type(x) == "number" then
- list = { bit.rshift(x, 16), bit.band(x, 0xFFFF) }
-
- elseif type(x) == "string" then
- if x:find(":") then x = IPv6(x) else x = IPv4(x) end
- if x then
- assert( x[1] == family, "Can't mix IPv4 and IPv6 addresses" )
- list = { unpack(x[2]) }
- end
-
- elseif type(x) == "table" and type(x[2]) == "table" then
- assert( x[1] == family, "Can't mix IPv4 and IPv6 addresses" )
- list = { unpack(x[2]) }
-
- elseif type(x) == "table" then
- list = { unpack(x) }
- end
-
- assert( list, "Invalid operand" )
-
- return list
-end
-
-local function __mask16(bits)
- return bit.lshift( bit.rshift( 0xFFFF, 16 - bits % 16 ), 16 - bits % 16 )
-end
-
-local function __not16(bits)
- return bit.band( bit.bnot( __mask16(bits) ), 0xFFFF )
-end
-
-local function __maxlen(family)
- return ( family == FAMILY_INET4 ) and 32 or 128
-end
-
-local function __sublen(family)
- return ( family == FAMILY_INET4 ) and 30 or 127
-end
-
-
---- Convert given short value to network byte order on little endian hosts
--- @param x Unsigned integer value between 0x0000 and 0xFFFF
--- @return Byte-swapped value
--- @see htonl
--- @see ntohs
-function htons(x)
- if LITTLE_ENDIAN then
- return bit.bor(
- bit.rshift( x, 8 ),
- bit.band( bit.lshift( x, 8 ), 0xFF00 )
- )
- else
- return x
- end
-end
-
---- Convert given long value to network byte order on little endian hosts
--- @param x Unsigned integer value between 0x00000000 and 0xFFFFFFFF
--- @return Byte-swapped value
--- @see htons
--- @see ntohl
-function htonl(x)
- if LITTLE_ENDIAN then
- return bit.bor(
- bit.lshift( htons( bit.band( x, 0xFFFF ) ), 16 ),
- htons( bit.rshift( x, 16 ) )
- )
- else
- return x
- end
-end
-
---- Convert given short value to host byte order on little endian hosts
--- @class function
--- @name ntohs
--- @param x Unsigned integer value between 0x0000 and 0xFFFF
--- @return Byte-swapped value
--- @see htonl
--- @see ntohs
-ntohs = htons
-
---- Convert given short value to host byte order on little endian hosts
--- @class function
--- @name ntohl
--- @param x Unsigned integer value between 0x00000000 and 0xFFFFFFFF
--- @return Byte-swapped value
--- @see htons
--- @see ntohl
-ntohl = htonl
-
-
---- Parse given IPv4 address in dotted quad or CIDR notation. If an optional
--- netmask is given as second argument and the IP address is encoded in CIDR
--- notation then the netmask parameter takes precedence. If neither a CIDR
--- encoded prefix nor a netmask parameter is given, then a prefix length of
--- 32 bit is assumed.
--- @param address IPv4 address in dotted quad or CIDR notation
--- @param netmask IPv4 netmask in dotted quad notation (optional)
--- @return luci.ip.cidr instance or nil if given address was invalid
--- @see IPv6
--- @see Hex
-function IPv4(address, netmask)
- address = address or "0.0.0.0/0"
-
- local obj = __bless({ FAMILY_INET4 })
-
- local data = {}
- local prefix = address:match("/(.+)")
- address = address:gsub("/.+","")
- address = address:gsub("^%[(.*)%]$", "%1"):upper():gsub("^::FFFF:", "")
-
- if netmask then
- prefix = obj:prefix(netmask)
- elseif prefix then
- prefix = tonumber(prefix)
- if not prefix or prefix < 0 or prefix > 32 then return nil end
- else
- prefix = 32
- end
-
- local b1, b2, b3, b4 = address:match("^(%d+)%.(%d+)%.(%d+)%.(%d+)$")
-
- b1 = tonumber(b1)
- b2 = tonumber(b2)
- b3 = tonumber(b3)
- b4 = tonumber(b4)
-
- if b1 and b1 <= 255 and
- b2 and b2 <= 255 and
- b3 and b3 <= 255 and
- b4 and b4 <= 255 and
- prefix
- then
- table.insert(obj, { b1 * 256 + b2, b3 * 256 + b4 })
- table.insert(obj, prefix)
- return obj
- end
-end
-
---- Parse given IPv6 address in full, compressed, mixed or CIDR notation.
--- If an optional netmask is given as second argument and the IP address is
--- encoded in CIDR notation then the netmask parameter takes precedence.
--- If neither a CIDR encoded prefix nor a netmask parameter is given, then a
--- prefix length of 128 bit is assumed.
--- @param address IPv6 address in full/compressed/mixed or CIDR notation
--- @param netmask IPv6 netmask in full/compressed/mixed notation (optional)
--- @return luci.ip.cidr instance or nil if given address was invalid
--- @see IPv4
--- @see Hex
-function IPv6(address, netmask)
- address = address or "::/0"
-
- local obj = __bless({ FAMILY_INET6 })
-
- local data = {}
- local prefix = address:match("/(.+)")
- address = address:gsub("/.+","")
- address = address:gsub("^%[(.*)%]$", "%1")
-
- if netmask then
- prefix = obj:prefix(netmask)
- elseif prefix then
- prefix = tonumber(prefix)
- if not prefix or prefix < 0 or prefix > 128 then return nil end
- else
- prefix = 128
- end
-
- local borderl = address:sub(1, 1) == ":" and 2 or 1
- local borderh, zeroh, chunk, block, i
-
- if #address > 45 then return nil end
-
- repeat
- borderh = address:find(":", borderl, true)
- if not borderh then break end
-
- block = tonumber(address:sub(borderl, borderh - 1), 16)
- if block and block <= 0xFFFF then
- data[#data+1] = block
- else
- if zeroh or borderh - borderl > 1 then return nil end
- zeroh = #data + 1
- end
-
- borderl = borderh + 1
- until #data == 7
-
- chunk = address:sub(borderl)
- if #chunk > 0 and #chunk <= 4 then
- block = tonumber(chunk, 16)
- if not block or block > 0xFFFF then return nil end
-
- data[#data+1] = block
- elseif #chunk > 4 then
- if #data == 7 or #chunk > 15 then return nil end
- borderl = 1
- for i=1, 4 do
- borderh = chunk:find(".", borderl, true)
- if not borderh and i < 4 then return nil end
- borderh = borderh and borderh - 1
-
- block = tonumber(chunk:sub(borderl, borderh))
- if not block or block > 255 then return nil end
-
- if i == 1 or i == 3 then
- data[#data+1] = block * 256
- else
- data[#data] = data[#data] + block
- end
-
- borderl = borderh and borderh + 2
- end
- end
-
- if zeroh then
- if #data == 8 then return nil end
- while #data < 8 do
- table.insert(data, zeroh, 0)
- end
- end
-
- if #data == 8 and prefix then
- table.insert(obj, data)
- table.insert(obj, prefix)
- return obj
- end
-end
-
---- Transform given hex-encoded value to luci.ip.cidr instance of specified
--- address family.
--- @param hex String containing hex encoded value
--- @param prefix Prefix length of CIDR instance (optional, default is 32/128)
--- @param family Address family, either luci.ip.FAMILY_INET4 or FAMILY_INET6
--- @param swap Bool indicating whether to swap byteorder on low endian host
--- @return luci.ip.cidr instance or nil if given value was invalid
--- @see IPv4
--- @see IPv6
-function Hex( hex, prefix, family, swap )
- family = ( family ~= nil ) and family or FAMILY_INET4
- swap = ( swap == nil ) and true or swap
- prefix = prefix or __maxlen(family)
-
- local len = __maxlen(family)
- local tmp = ""
- local data = { }
- local i
-
- for i = 1, (len/4) - #hex do tmp = tmp .. '0' end
-
- if swap and LITTLE_ENDIAN then
- for i = #hex, 1, -2 do tmp = tmp .. hex:sub( i - 1, i ) end
- else
- tmp = tmp .. hex
- end
-
- hex = tmp
-
- for i = 1, ( len / 4 ), 4 do
- local n = tonumber( hex:sub( i, i+3 ), 16 )
- if n then
- data[#data+1] = n
- else
- return nil
- end
- end
-
- return __bless({ family, data, prefix })
-end
-
-
---- LuCI IP Library / CIDR instances
--- @class module
--- @cstyle instance
--- @name luci.ip.cidr
-cidr = util.class()
-
---- Test whether the instance is a IPv4 address.
--- @return Boolean indicating a IPv4 address type
--- @see cidr.is6
-function cidr.is4( self )
- return self[1] == FAMILY_INET4
-end
-
---- Test whether this instance is an IPv4 RFC1918 private address
--- @return Boolean indicating whether this instance is an RFC1918 address
-function cidr.is4rfc1918( self )
- if self[1] == FAMILY_INET4 then
- return ((self[2][1] >= 0x0A00) and (self[2][1] <= 0x0AFF)) or
- ((self[2][1] >= 0xAC10) and (self[2][1] <= 0xAC1F)) or
- (self[2][1] == 0xC0A8)
- end
- return false
-end
-
---- Test whether this instance is an IPv4 link-local address (Zeroconf)
--- @return Boolean indicating whether this instance is IPv4 link-local
-function cidr.is4linklocal( self )
- if self[1] == FAMILY_INET4 then
- return (self[2][1] == 0xA9FE)
- end
- return false
-end
-
---- Test whether the instance is a IPv6 address.
--- @return Boolean indicating a IPv6 address type
--- @see cidr.is4
-function cidr.is6( self )
- return self[1] == FAMILY_INET6
-end
-
---- Test whether this instance is an IPv6 link-local address
--- @return Boolean indicating whether this instance is IPv6 link-local
-function cidr.is6linklocal( self )
- if self[1] == FAMILY_INET6 then
- return (self[2][1] >= 0xFE80) and (self[2][1] <= 0xFEBF)
- end
- return false
-end
-
---- Return a corresponding string representation of the instance.
--- If the prefix length is lower then the maximum possible prefix length for the
--- corresponding address type then the address is returned in CIDR notation,
--- otherwise the prefix will be left out.
-function cidr.string( self )
- local str
- if self:is4() then
- str = string.format(
- "%d.%d.%d.%d",
- bit.rshift(self[2][1], 8), bit.band(self[2][1], 0xFF),
- bit.rshift(self[2][2], 8), bit.band(self[2][2], 0xFF)
- )
- if self[3] < 32 then
- str = str .. "/" .. self[3]
- end
- elseif self:is6() then
- str = string.format( "%X:%X:%X:%X:%X:%X:%X:%X", unpack(self[2]) )
- if self[3] < 128 then
- str = str .. "/" .. self[3]
- end
- end
- return str
-end
-
---- Test whether the value of the instance is lower then the given address.
--- This function will throw an exception if the given address has a different
--- family than this instance.
--- @param addr A luci.ip.cidr instance to compare against
--- @return Boolean indicating whether this instance is lower
--- @see cidr.higher
--- @see cidr.equal
-function cidr.lower( self, addr )
- assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
- local i
- for i = 1, #self[2] do
- if self[2][i] ~= addr[2][i] then
- return self[2][i] < addr[2][i]
- end
- end
- return false
-end
-
---- Test whether the value of the instance is higher then the given address.
--- This function will throw an exception if the given address has a different
--- family than this instance.
--- @param addr A luci.ip.cidr instance to compare against
--- @return Boolean indicating whether this instance is higher
--- @see cidr.lower
--- @see cidr.equal
-function cidr.higher( self, addr )
- assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
- local i
- for i = 1, #self[2] do
- if self[2][i] ~= addr[2][i] then
- return self[2][i] > addr[2][i]
- end
- end
- return false
-end
-
---- Test whether the value of the instance is equal to the given address.
--- This function will throw an exception if the given address is a different
--- family than this instance.
--- @param addr A luci.ip.cidr instance to compare against
--- @return Boolean indicating whether this instance is equal
--- @see cidr.lower
--- @see cidr.higher
-function cidr.equal( self, addr )
- assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
- local i
- for i = 1, #self[2] do
- if self[2][i] ~= addr[2][i] then
- return false
- end
- end
- return true
-end
-
---- Return the prefix length of this CIDR instance.
--- @param mask Override instance prefix with given netmask (optional)
--- @return Prefix length in bit
-function cidr.prefix( self, mask )
- local prefix = self[3]
-
- if mask then
- prefix = 0
-
- local stop = false
- local obj = type(mask) ~= "table"
- and ( self:is4() and IPv4(mask) or IPv6(mask) ) or mask
-
- if not obj then return nil end
-
- local _, word
- for _, word in ipairs(obj[2]) do
- if word == 0xFFFF then
- prefix = prefix + 16
- else
- local bitmask = bit.lshift(1, 15)
- while bit.band(word, bitmask) == bitmask do
- prefix = prefix + 1
- bitmask = bit.lshift(1, 15 - (prefix % 16))
- end
-
- break
- end
- end
- end
-
- return prefix
-end
-
---- Return a corresponding CIDR representing the network address of this
--- instance.
--- @param bits Override prefix length of this instance (optional)
--- @return CIDR instance containing the network address
--- @see cidr.host
--- @see cidr.broadcast
--- @see cidr.mask
-function cidr.network( self, bits )
- local data = { }
- bits = bits or self[3]
-
- local i
- for i = 1, math.floor( bits / 16 ) do
- data[#data+1] = self[2][i]
- end
-
- if #data < #self[2] then
- data[#data+1] = bit.band( self[2][1+#data], __mask16(bits) )
-
- for i = #data + 1, #self[2] do
- data[#data+1] = 0
- end
- end
-
- return __bless({ self[1], data, __maxlen(self[1]) })
-end
-
---- Return a corresponding CIDR representing the host address of this
--- instance. This is intended to extract the host address from larger subnet.
--- @return CIDR instance containing the network address
--- @see cidr.network
--- @see cidr.broadcast
--- @see cidr.mask
-function cidr.host( self )
- return __bless({ self[1], self[2], __maxlen(self[1]) })
-end
-
---- Return a corresponding CIDR representing the netmask of this instance.
--- @param bits Override prefix length of this instance (optional)
--- @return CIDR instance containing the netmask
--- @see cidr.network
--- @see cidr.host
--- @see cidr.broadcast
-function cidr.mask( self, bits )
- local data = { }
- bits = bits or self[3]
-
- for i = 1, math.floor( bits / 16 ) do
- data[#data+1] = 0xFFFF
- end
-
- if #data < #self[2] then
- data[#data+1] = __mask16(bits)
-
- for i = #data + 1, #self[2] do
- data[#data+1] = 0
- end
- end
-
- return __bless({ self[1], data, __maxlen(self[1]) })
-end
-
---- Return CIDR containing the broadcast address of this instance.
--- @return CIDR instance containing the netmask, always nil for IPv6
--- @see cidr.network
--- @see cidr.host
--- @see cidr.mask
-function cidr.broadcast( self )
- -- IPv6 has no broadcast addresses (XXX: assert() instead?)
- if self[1] == FAMILY_INET4 then
- local data = { unpack(self[2]) }
- local offset = math.floor( self[3] / 16 ) + 1
-
- if offset <= #data then
- data[offset] = bit.bor( data[offset], __not16(self[3]) )
- for i = offset + 1, #data do data[i] = 0xFFFF end
-
- return __bless({ self[1], data, __maxlen(self[1]) })
- end
- end
-end
-
---- Test whether this instance fully contains the given CIDR instance.
--- @param addr CIDR instance to test against
--- @return Boolean indicating whether this instance contains the given CIDR
-function cidr.contains( self, addr )
- assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
-
- if self:prefix() <= addr:prefix() then
- return self:network() == addr:network(self:prefix())
- end
-
- return false
-end
-
---- Add specified amount of hosts to this instance.
--- @param amount Number of hosts to add to this instance
--- @param inplace Boolen indicating whether to alter values inplace (optional)
--- @return CIDR representing the new address or nil on overflow error
--- @see cidr.sub
-function cidr.add( self, amount, inplace )
- local pos
- local data = { unpack(self[2]) }
- local shorts = __array16( amount, self[1] )
-
- for pos = #data, 1, -1 do
- local add = ( #shorts > 0 ) and table.remove( shorts, #shorts ) or 0
- if ( data[pos] + add ) > 0xFFFF then
- data[pos] = ( data[pos] + add ) % 0xFFFF
- if pos > 1 then
- data[pos-1] = data[pos-1] + ( add - data[pos] )
- else
- return nil
- end
- else
- data[pos] = data[pos] + add
- end
- end
-
- if inplace then
- self[2] = data
- return self
- else
- return __bless({ self[1], data, self[3] })
- end
-end
-
---- Substract specified amount of hosts from this instance.
--- @param amount Number of hosts to substract from this instance
--- @param inplace Boolen indicating whether to alter values inplace (optional)
--- @return CIDR representing the new address or nil on underflow error
--- @see cidr.add
-function cidr.sub( self, amount, inplace )
- local pos
- local data = { unpack(self[2]) }
- local shorts = __array16( amount, self[1] )
-
- for pos = #data, 1, -1 do
- local sub = ( #shorts > 0 ) and table.remove( shorts, #shorts ) or 0
- if ( data[pos] - sub ) < 0 then
- data[pos] = ( sub - data[pos] ) % 0xFFFF
- if pos > 1 then
- data[pos-1] = data[pos-1] - ( sub + data[pos] )
- else
- return nil
- end
- else
- data[pos] = data[pos] - sub
- end
- end
-
- if inplace then
- self[2] = data
- return self
- else
- return __bless({ self[1], data, self[3] })
- end
-end
-
---- Return CIDR containing the lowest available host address within this subnet.
--- @return CIDR containing the host address, nil if subnet is too small
--- @see cidr.maxhost
-function cidr.minhost( self )
- if self[3] <= __sublen(self[1]) then
- -- 1st is Network Address in IPv4 and Subnet-Router Anycast Adresse in IPv6
- return self:network():add(1, true)
- end
-end
-
---- Return CIDR containing the highest available host address within the subnet.
--- @return CIDR containing the host address, nil if subnet is too small
--- @see cidr.minhost
-function cidr.maxhost( self )
- if self[3] <= __sublen(self[1]) then
- local i
- local data = { unpack(self[2]) }
- local offset = math.floor( self[3] / 16 ) + 1
-
- data[offset] = bit.bor( data[offset], __not16(self[3]) )
- for i = offset + 1, #data do data[i] = 0xFFFF end
- data = __bless({ self[1], data, __maxlen(self[1]) })
-
- -- Last address in reserved for Broadcast Address in IPv4
- if data[1] == FAMILY_INET4 then data:sub(1, true) end
-
- return data
- end
-end
projects / project / luci.git / blobdiff