From: Jo-Philipp Wich Date: Sat, 9 Aug 2008 01:06:28 +0000 (+0000) Subject: * luci/libs: added broadcast(), minhost() and maxhost() to luci.ip, allow various... X-Git-Tag: 0.8.0~488 X-Git-Url: https://git.archive.openwrt.org/?p=project%2Fluci.git;a=commitdiff_plain;h=648126f6d00cfca1313c00e29f68d1a1a260dd04 * luci/libs: added broadcast(), minhost() and maxhost() to luci.ip, allow various datatypes as add() and sub() operands, extended add() and sub() to modify data inplace when flag is set --- diff --git a/libs/core/luasrc/ip.lua b/libs/core/luasrc/ip.lua index 1245dc3df..bcb821a46 100644 --- a/libs/core/luasrc/ip.lua +++ b/libs/core/luasrc/ip.lua @@ -41,21 +41,49 @@ local function __bless(x) } ) 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 = 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 @@ -255,9 +283,9 @@ end 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 = { } @@ -417,6 +445,7 @@ end -- @param bits Override prefix length of this instance (optional) -- @return CIDR instance containing the network address -- @see host +-- @see broadcast -- @see mask function cidr.network( self, bits ) local data = { } @@ -434,16 +463,17 @@ function cidr.network( self, bits ) 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 broadcast -- @see mask function cidr.host( self ) - return __bless({ self[1], data, __length(self[1]) }) + return __bless({ self[1], data, __maxlen(self[1]) }) end --- Return a corresponding CIDR representing the netmask of this instance. @@ -451,6 +481,7 @@ end -- @return CIDR instance containing the netmask -- @see network -- @see host +-- @see broadcast function cidr.mask( self, bits ) local data = { } bits = bits or self[3] @@ -467,7 +498,28 @@ function cidr.mask( self, bits ) 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. +-- @param bits Override prefix length of this instance (optional) +-- @return CIDR instance containing the netmask, always nil for IPv6 +-- @see network +-- @see host +-- @see 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. @@ -485,50 +537,95 @@ 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 sub -function cidr.add( self, amount ) - local shorts = { bit.rshift(amount, 16), bit.band(amount, 0xFFFF) } +function cidr.add( self, amount, inplace ) local data = { unpack(self[2]) } - - 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] ) + local shorts = __array16( amount, self[1] ) + + if shorts then + 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 - return nil + data[pos] = data[pos] + add end - else - data[pos] = data[pos] + add 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) } +function cidr.sub( self, amount, inplace ) local data = { unpack(self[2]) } - - 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] ) + local shorts = __array16( amount, self[1] ) + + if shorts then + 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 - return nil + data[pos] = data[pos] - sub end - else - data[pos] = data[pos] - sub 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 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 minhost +function cidr.maxhost( self ) + if self[3] <= __sublen(self[1]) then + 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