3 LuCI ip calculation libarary
4 (c) 2008 Jo-Philipp Wich <xm@leipzig.freifunk.net>
5 (c) 2008 Steven Barth <steven@midlink.org>
7 Licensed under the Apache License, Version 2.0 (the "License");
8 you may not use this file except in compliance with the License.
9 You may obtain a copy of the License at
11 http://www.apache.org/licenses/LICENSE-2.0
17 module( "luci.ip", package.seeall )
22 LITTLE_ENDIAN = not luci.util.bigendian()
23 BIG_ENDIAN = not LITTLE_ENDIAN
29 local function __bless(x)
30 return setmetatable( x, {
31 __index = luci.ip.cidr,
32 __add = luci.ip.cidr.add,
33 __lt = luci.ip.cidr.lower,
34 __eq = luci.ip.cidr.equal,
37 return luci.ip.cidr.equal(...) or luci.ip.cidr.lower(...)
42 local function __mask16(bits)
44 bit.rshift( 0xFFFF, 16 - bits % 16 ),
49 -- htons(), htonl(), ntohs(), ntohl()
55 bit.band( bit.lshift( x, 8 ), 0xFF00 )
65 bit.lshift( htons( bit.band( x, 0xFFFF ) ), 16 ),
66 htons( bit.rshift( x, 16 ) )
77 function IPv4(address)
79 local prefix = address:match("/(.+)")
82 address = address:gsub("/.+","")
83 prefix = tonumber(prefix)
84 if not prefix or prefix < 0 or prefix > 32 then return nil end
89 local b1, b2, b3, b4 = address:match("(%d+)%.(%d+)%.(%d+)%.(%d+)")
96 if b1 and b1 <= 255 and
103 { b1 * 256 + b2, b3 * 256 + b4 },
109 function IPv6(address)
111 local prefix = address:match("/(.+)")
114 address = address:gsub("/.+","")
115 prefix = tonumber(prefix)
116 if not prefix or prefix < 0 or prefix > 128 then return nil end
121 local borderl = address:sub(1, 1) == ":" and 2 or 1
122 local borderh, zeroh, chunk, block
124 if #address > 45 then return nil end
127 borderh = address:find(":", borderl, true)
128 if not borderh then break end
130 block = tonumber(address:sub(borderl, borderh - 1), 16)
131 if block and block <= 65535 then
132 table.insert(data, block)
134 if zeroh or borderh - borderl > 1 then return nil end
138 borderl = borderh + 1
141 chunk = address:sub(borderl)
142 if #chunk > 0 and #chunk <= 4 then
143 block = tonumber(chunk, 16)
144 if not block or block > 65535 then return nil end
146 table.insert(data, block)
147 elseif #chunk > 4 then
148 if #data == 7 or #chunk > 15 then return nil end
151 borderh = chunk:find(".", borderl, true)
152 if not borderh and i < 4 then return nil end
153 borderh = borderh and borderh - 1
155 block = tonumber(chunk:sub(borderl, borderh))
156 if not block or block > 255 then return nil end
158 if i == 1 or i == 3 then
159 table.insert(data, block * 256)
161 data[#data] = data[#data] + block
164 borderl = borderh and borderh + 2
169 if #data == 8 then return nil end
171 table.insert(data, zeroh, 0)
176 return __bless({ FAMILY_INET6, data, prefix })
181 cidr = luci.util.class()
183 function cidr.is4( self )
184 return self[1] == FAMILY_INET4
187 function cidr.is6( self )
188 return self[1] == FAMILY_INET6
191 function cidr.string( self )
196 bit.rshift(self[2][1], 8), bit.band(self[2][1], 0xFF),
197 bit.rshift(self[2][2], 8), bit.band(self[2][2], 0xFF)
200 str = str .. "/" .. self[3]
202 elseif self:is6() then
203 str = string.format( "%X:%X:%X:%X:%X:%X:%X:%X", unpack(self[2]) )
204 if self[3] < 128 then
205 str = str .. "/" .. self[3]
211 function cidr.lower( self, addr )
212 assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
213 for i = 1, #self[2] do
214 if self[2][i] ~= addr[2][i] then
215 return self[2][i] < addr[2][i]
221 function cidr.higher( self, addr )
222 assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
223 for i = 1, #self[2] do
224 if self[2][i] ~= addr[2][i] then
225 return self[2][i] > addr[2][i]
231 function cidr.equal( self, addr )
232 assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
233 for i = 1, #self[2] do
234 if self[2][i] ~= addr[2][i] then
241 function cidr.prefix( self )
245 function cidr.network( self )
248 for i = 1, math.floor( self[3] / 16 ) do
249 table.insert( data, self[2][i] )
252 table.insert( data, bit.band( self[2][1+#data], __mask16(self[3]) ) )
254 for i = #data, #self[2] do
255 table.insert( data, 0 )
258 return __bless({ self[1], data, self:is4() and 32 or 128 })
261 function cidr.host( self )
262 return __bless({ self[1], data, self:is4() and 32 or 128 })
265 function cidr.mask( self, bits )
267 bits = bits or self[3]
269 for i = 1, math.floor( bits / 16 ) do
270 table.insert( data, 0xFFFF )
273 table.insert( data, __mask16(bits) )
275 for i = #data + 1, #self[2] do
276 table.insert( data, 0 )
279 return __bless({ self[1], data, self:is4() and 32 or 128 })
282 function cidr.contains( self, addr )
283 if self:mask() <= addr:mask() then
284 return self:mask(addr:prefix()) == addr:mask()
290 function cidr.add( self, amount )
291 local shorts = { bit.rshift(amount, 16), bit.band(amount, 0xFFFF) }
292 local data = { unpack(self[2]) }
294 for pos = #data, 1, -1 do
295 local add = ( #shorts > 0 ) and table.remove( shorts, #shorts ) or 0
296 if ( data[pos] + add ) > 0xFFFF then
297 data[pos] = ( data[pos] + add ) % 0xFFFF
299 data[pos-1] = data[pos-1] + ( add - data[pos] )
302 data[pos] = data[pos] + add
306 return __bless({ self[1], data, self[3] })