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, netmask)
78 address = address or "0.0.0.0/0"
80 local obj = __bless({ FAMILY_INET4 })
83 local prefix = address:match("/(.+)")
86 prefix = obj:prefix(netmask)
88 address = address:gsub("/.+","")
89 prefix = tonumber(prefix)
90 if not prefix or prefix < 0 or prefix > 32 then return nil end
95 local b1, b2, b3, b4 = address:match("^(%d+)%.(%d+)%.(%d+)%.(%d+)$")
102 if b1 and b1 <= 255 and
108 table.insert(obj, { b1 * 256 + b2, b3 * 256 + b4 })
109 table.insert(obj, prefix)
114 function IPv6(address, netmask)
115 address = address or "::/0"
117 local obj = __bless({ FAMILY_INET6 })
120 local prefix = address:match("/(.+)")
123 prefix = obj:prefix(netmask)
125 address = address:gsub("/.+","")
126 prefix = tonumber(prefix)
127 if not prefix or prefix < 0 or prefix > 128 then return nil end
132 local borderl = address:sub(1, 1) == ":" and 2 or 1
133 local borderh, zeroh, chunk, block
135 if #address > 45 then return nil end
138 borderh = address:find(":", borderl, true)
139 if not borderh then break end
141 block = tonumber(address:sub(borderl, borderh - 1), 16)
142 if block and block <= 65535 then
143 table.insert(data, block)
145 if zeroh or borderh - borderl > 1 then return nil end
149 borderl = borderh + 1
152 chunk = address:sub(borderl)
153 if #chunk > 0 and #chunk <= 4 then
154 block = tonumber(chunk, 16)
155 if not block or block > 65535 then return nil end
157 table.insert(data, block)
158 elseif #chunk > 4 then
159 if #data == 7 or #chunk > 15 then return nil end
162 borderh = chunk:find(".", borderl, true)
163 if not borderh and i < 4 then return nil end
164 borderh = borderh and borderh - 1
166 block = tonumber(chunk:sub(borderl, borderh))
167 if not block or block > 255 then return nil end
169 if i == 1 or i == 3 then
170 table.insert(data, block * 256)
172 data[#data] = data[#data] + block
175 borderl = borderh and borderh + 2
180 if #data == 8 then return nil end
182 table.insert(data, zeroh, 0)
186 if #data == 8 and prefix then
187 table.insert(obj, data)
188 table.insert(obj, prefix)
194 cidr = luci.util.class()
196 function cidr.is4( self )
197 return self[1] == FAMILY_INET4
200 function cidr.is6( self )
201 return self[1] == FAMILY_INET6
204 function cidr.string( self )
209 bit.rshift(self[2][1], 8), bit.band(self[2][1], 0xFF),
210 bit.rshift(self[2][2], 8), bit.band(self[2][2], 0xFF)
213 str = str .. "/" .. self[3]
215 elseif self:is6() then
216 str = string.format( "%X:%X:%X:%X:%X:%X:%X:%X", unpack(self[2]) )
217 if self[3] < 128 then
218 str = str .. "/" .. self[3]
224 function cidr.lower( self, addr )
225 assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
226 for i = 1, #self[2] do
227 if self[2][i] ~= addr[2][i] then
228 return self[2][i] < addr[2][i]
234 function cidr.higher( self, addr )
235 assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
236 for i = 1, #self[2] do
237 if self[2][i] ~= addr[2][i] then
238 return self[2][i] > addr[2][i]
244 function cidr.equal( self, addr )
245 assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
246 for i = 1, #self[2] do
247 if self[2][i] ~= addr[2][i] then
254 function cidr.prefix( self, mask )
255 local prefix = self[3]
260 local obj = self:is4() and IPv4(mask) or IPv6(mask)
266 for i, block in ipairs(obj[2]) do
267 local pos = bit.lshift(1, 15)
269 if bit.band(block, pos) == pos then
278 pos = bit.rshift(pos, 1)
286 function cidr.network( self )
289 for i = 1, math.floor( self[3] / 16 ) do
290 table.insert( data, self[2][i] )
293 table.insert( data, bit.band( self[2][1+#data], __mask16(self[3]) ) )
295 for i = #data, #self[2] do
296 table.insert( data, 0 )
299 return __bless({ self[1], data, self:is4() and 32 or 128 })
302 function cidr.host( self )
303 return __bless({ self[1], data, self:is4() and 32 or 128 })
306 function cidr.mask( self, bits )
308 bits = bits or self[3]
310 for i = 1, math.floor( bits / 16 ) do
311 table.insert( data, 0xFFFF )
314 table.insert( data, __mask16(bits) )
316 for i = #data + 1, #self[2] do
317 table.insert( data, 0 )
320 return __bless({ self[1], data, self:is4() and 32 or 128 })
323 function cidr.contains( self, addr )
324 local mask1 = self:mask()
325 local mask2 = addr:mask()
326 if mask1 <= mask2 then
327 return self:mask(addr:prefix()) == mask2
333 function cidr.add( self, amount )
334 local shorts = { bit.rshift(amount, 16), bit.band(amount, 0xFFFF) }
335 local data = { unpack(self[2]) }
337 for pos = #data, 1, -1 do
338 local add = ( #shorts > 0 ) and table.remove( shorts, #shorts ) or 0
339 if ( data[pos] + add ) > 0xFFFF then
340 data[pos] = ( data[pos] + add ) % 0xFFFF
342 data[pos-1] = data[pos-1] + ( add - data[pos] )
345 data[pos] = data[pos] + add
349 return __bless({ self[1], data, self[3] })