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"
81 local prefix = address:match("/(.+)")
84 prefix = IPv4():prefix(netmask)
86 address = address:gsub("/.+","")
87 prefix = tonumber(prefix)
88 if not prefix or prefix < 0 or prefix > 32 then return nil end
93 local b1, b2, b3, b4 = address:match("^(%d+)%.(%d+)%.(%d+)%.(%d+)$")
100 if b1 and b1 <= 255 and
107 { b1 * 256 + b2, b3 * 256 + b4 },
113 function IPv6(address, netmask)
114 address = address or "::/0"
117 local prefix = address:match("/(.+)")
120 prefix = IPv6():prefix(netmask)
122 address = address:gsub("/.+","")
123 prefix = tonumber(prefix)
124 if not prefix or prefix < 0 or prefix > 128 then return nil end
129 local borderl = address:sub(1, 1) == ":" and 2 or 1
130 local borderh, zeroh, chunk, block
132 if #address > 45 then return nil end
135 borderh = address:find(":", borderl, true)
136 if not borderh then break end
138 block = tonumber(address:sub(borderl, borderh - 1), 16)
139 if block and block <= 65535 then
140 table.insert(data, block)
142 if zeroh or borderh - borderl > 1 then return nil end
146 borderl = borderh + 1
149 chunk = address:sub(borderl)
150 if #chunk > 0 and #chunk <= 4 then
151 block = tonumber(chunk, 16)
152 if not block or block > 65535 then return nil end
154 table.insert(data, block)
155 elseif #chunk > 4 then
156 if #data == 7 or #chunk > 15 then return nil end
159 borderh = chunk:find(".", borderl, true)
160 if not borderh and i < 4 then return nil end
161 borderh = borderh and borderh - 1
163 block = tonumber(chunk:sub(borderl, borderh))
164 if not block or block > 255 then return nil end
166 if i == 1 or i == 3 then
167 table.insert(data, block * 256)
169 data[#data] = data[#data] + block
172 borderl = borderh and borderh + 2
177 if #data == 8 then return nil end
179 table.insert(data, zeroh, 0)
184 return __bless({ FAMILY_INET6, data, prefix })
189 cidr = luci.util.class()
191 function cidr.is4( self )
192 return self[1] == FAMILY_INET4
195 function cidr.is6( self )
196 return self[1] == FAMILY_INET6
199 function cidr.string( self )
204 bit.rshift(self[2][1], 8), bit.band(self[2][1], 0xFF),
205 bit.rshift(self[2][2], 8), bit.band(self[2][2], 0xFF)
208 str = str .. "/" .. self[3]
210 elseif self:is6() then
211 str = string.format( "%X:%X:%X:%X:%X:%X:%X:%X", unpack(self[2]) )
212 if self[3] < 128 then
213 str = str .. "/" .. self[3]
219 function cidr.lower( self, addr )
220 assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
221 for i = 1, #self[2] do
222 if self[2][i] ~= addr[2][i] then
223 return self[2][i] < addr[2][i]
229 function cidr.higher( self, addr )
230 assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
231 for i = 1, #self[2] do
232 if self[2][i] ~= addr[2][i] then
233 return self[2][i] > addr[2][i]
239 function cidr.equal( self, addr )
240 assert( self[1] == addr[1], "Can't compare IPv4 and IPv6 addresses" )
241 for i = 1, #self[2] do
242 if self[2][i] ~= addr[2][i] then
249 function cidr.prefix( self, mask )
250 local prefix = self[3]
255 local obj = self:is4() and IPv4(mask) or IPv6(mask)
260 for i, block in ipairs(obj[2]) do
261 local pos = bit.lshift(1, 15)
263 if bit.band(block, pos) == pos then
268 pos = bit.rshift(pos, 1)
276 function cidr.network( self )
279 for i = 1, math.floor( self[3] / 16 ) do
280 table.insert( data, self[2][i] )
283 table.insert( data, bit.band( self[2][1+#data], __mask16(self[3]) ) )
285 for i = #data, #self[2] do
286 table.insert( data, 0 )
289 return __bless({ self[1], data, self:is4() and 32 or 128 })
292 function cidr.host( self )
293 return __bless({ self[1], data, self:is4() and 32 or 128 })
296 function cidr.mask( self, bits )
298 bits = bits or self[3]
300 for i = 1, math.floor( bits / 16 ) do
301 table.insert( data, 0xFFFF )
304 table.insert( data, __mask16(bits) )
306 for i = #data + 1, #self[2] do
307 table.insert( data, 0 )
310 return __bless({ self[1], data, self:is4() and 32 or 128 })
313 function cidr.contains( self, addr )
314 if self:mask() <= addr:mask() then
315 return self:mask(addr:prefix()) == addr:mask()
321 function cidr.add( self, amount )
322 local shorts = { bit.rshift(amount, 16), bit.band(amount, 0xFFFF) }
323 local data = { unpack(self[2]) }
325 for pos = #data, 1, -1 do
326 local add = ( #shorts > 0 ) and table.remove( shorts, #shorts ) or 0
327 if ( data[pos] + add ) > 0xFFFF then
328 data[pos] = ( data[pos] + add ) % 0xFFFF
330 data[pos-1] = data[pos-1] + ( add - data[pos] )
333 data[pos] = data[pos] + add
337 return __bless({ self[1], data, self[3] })