--- LuCI IP calculation library.
module( "luci.ip", package.seeall )
-require("bit")
-require("luci.util")
+require "nixio"
+local bit = nixio.bit
+local util = require "luci.util"
-LITTLE_ENDIAN = not luci.util.bigendian()
+--- 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
} )
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
- )
+ return bit.lshift( bit.rshift( 0xFFFF, 16 - bits % 16 ), 16 - bits % 16 )
end
-local function __length(family)
- if family == FAMILY_INET4 then
- return 32
- else
- return 128
- 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
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
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
local data = {}
local prefix = address:match("/(.+)")
address = address:gsub("/.+","")
+ address = address:gsub("^%[(.*)%]$", "%1"):upper():gsub("^::FFFF:", "")
if netmask then
prefix = obj:prefix(netmask)
local data = {}
local prefix = address:match("/(.+)")
address = address:gsub("/.+","")
+ address = address:gsub("^%[(.*)%]$", "%1")
if netmask then
prefix = obj:prefix(netmask)
end
local borderl = address:sub(1, 1) == ":" and 2 or 1
- local borderh, zeroh, chunk, block
+ local borderh, zeroh, chunk, block, i
if #address > 45 then return nil end
block = tonumber(address:sub(borderl, borderh - 1), 16)
if block and block <= 0xFFFF then
- table.insert(data, block)
+ data[#data+1] = block
else
if zeroh or borderh - borderl > 1 then return nil end
zeroh = #data + 1
block = tonumber(chunk, 16)
if not block or block > 0xFFFF then return nil end
- table.insert(data, block)
+ data[#data+1] = block
elseif #chunk > 4 then
if #data == 7 or #chunk > 15 then return nil end
borderl = 1
if not block or block > 255 then return nil end
if i == 1 or i == 3 then
- table.insert(data, block * 256)
+ data[#data+1] = block * 256
else
data[#data] = data[#data] + block
end
-- @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 weather to swap byteorder on low endian host
+-- @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 __length(family)
+ prefix = prefix or __maxlen(family)
- local len = __length(family)
+ local len = __maxlen(family)
local tmp = ""
local data = { }
+ local i
for i = 1, (len/4) - #hex do tmp = tmp .. '0' end
for i = 1, ( len / 4 ), 4 do
local n = tonumber( hex:sub( i, i+3 ), 16 )
if n then
- table.insert( data, n )
+ data[#data+1] = n
else
return nil
end
end
- return __bless({ family, data, len })
+ return __bless({ family, data, prefix })
end
--- LuCI IP Library / CIDR instances
-- @class module
+-- @cstyle instance
-- @name luci.ip.cidr
-cidr = luci.util.class()
+cidr = util.class()
---- Test weather the instance is a IPv4 address.
+--- Test whether the instance is a IPv4 address.
-- @return Boolean indicating a IPv4 address type
--- @see is6
+-- @see cidr.is6
function cidr.is4( self )
return self[1] == FAMILY_INET4
end
---- Test weather the instance is a IPv6 address.
+--- 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 is4
+-- @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,
return str
end
---- Test weather the value of the instance is lower then the given address.
+--- 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 weather this instance is lower
--- @see higher
--- @see equal
+-- @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]
return false
end
---- Test weather the value of the instance is higher then the given address.
+--- 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 weather this instance is higher
--- @see lower
--- @see equal
+-- @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]
return false
end
---- Test weather the value of the instance is uequal to the given address.
+--- 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 weather this instance is equal
--- @see lower
--- @see higher
+-- @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
--- Return the prefix length of this CIDR instance.
--- @return Prefix length in bit
+-- @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 = self:is4() and IPv4(mask) or IPv6(mask)
+ local obj = type(mask) ~= "table"
+ and ( self:is4() and IPv4(mask) or IPv6(mask) ) or mask
- if not obj then
- return nil
- end
+ if not obj then return nil end
- for i, block in ipairs(obj[2]) do
- local pos = bit.lshift(1, 15)
- for i=15, 0, -1 do
- if bit.band(block, pos) == pos then
- if not stop then
- prefix = prefix + 1
- else
- return nil
- end
- else
- stop = true
+ 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
- pos = bit.rshift(pos, 1)
+
+ break
end
end
end
-- instance.
-- @param bits Override prefix length of this instance (optional)
-- @return CIDR instance containing the network address
--- @see host
--- @see mask
+-- @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
- table.insert( data, self[2][i] )
+ data[#data+1] = self[2][i]
end
if #data < #self[2] then
- table.insert( data, bit.band( self[2][1+#data], __mask16(bits) ) )
+ data[#data+1] = bit.band( self[2][1+#data], __mask16(bits) )
for i = #data + 1, #self[2] do
- table.insert( data, 0 )
+ data[#data+1] = 0
end
end
- return __bless({ self[1], data, __length(self[1]) })
+ 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 network
--- @see mask
+-- @see cidr.network
+-- @see cidr.broadcast
+-- @see cidr.mask
function cidr.host( self )
- return __bless({ self[1], data, __length(self[1]) })
+ 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 network
--- @see host
+-- @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
- table.insert( data, 0xFFFF )
+ data[#data+1] = 0xFFFF
end
if #data < #self[2] then
- table.insert( data, __mask16(bits) )
+ data[#data+1] = __mask16(bits)
for i = #data + 1, #self[2] do
- table.insert( data, 0 )
+ data[#data+1] = 0
end
end
- return __bless({ self[1], data, __length(self[1]) })
+ 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 weather this instance fully contains the given CIDR instance.
+--- Test whether this instance fully contains the given CIDR instance.
-- @param addr CIDR instance to test against
--- @return Boolean indicating weather this instance contains the given CIDR
+-- @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" )
--- 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 sub
-function cidr.add( self, amount )
- local shorts = { bit.rshift(amount, 16), bit.band(amount, 0xFFFF) }
+-- @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
end
end
- return __bless({ self[1], data, self[3] })
+ 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 add
-function cidr.sub( self, amount )
- local shorts = { bit.rshift(amount, 16), bit.band(amount, 0xFFFF) }
+-- @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
end
end
- return __bless({ self[1], data, self[3] })
+ 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