o [NSE] Added ipv6 support to the wsdd, dnssd and upnp libraries. Applied

patch from Dan Miller that fixes errors in processing and sorting ipv6
  addresses in scripts using these libraries. [Daniel Miller, Patrik]

CHANGELOG

@@ -1,5 +1,9 @@
 # Nmap Changelog ($Id$); -*-text-*-
 
+o [NSE] Added ipv6 support to the wsdd, dnssd and upnp libraries. Applied
+  patch from Dan Miller that fixes errors in processing and sorting ipv6
+  addresses in scripts using these libraries. [Daniel Miller, Patrik]
+
 o [NSE] Added minimal Service Location Protocol (SLP) library and the script
   broadcast-novell-locate that detects servers running eDirectory. [Patrik]
 

nselib/dnssd.lua

@@ -41,31 +41,17 @@ module(... or "dnssd", package.seeall)
 
 require 'dns'
 require 'target'
+require 'ipOps'
 
 Util = {
-	
-	--- Converts a string ip to a numeric value suitable for comparing
-	--
-	-- @param ip string containing the ip to convert
-	-- @return number containing the converted ip
-	ipToNumber = function(ip)
-		local o1, o2, o3, o4 = ip:match("^(%d*)%.(%d*)%.(%d*)%.(%d*)$")
-		return (256^3) * o1 + (256^2) * o2 + (256^1) * o3 + (256^0) * o4
-	end,
 
 	--- Compare function used for sorting IP-addresses
 	--
 	-- @param a table containing first item
 	-- @param b table containing second item
-	-- @return true if the port of a is less than the port of b
+	-- @return true if a is less than b
 	ipCompare = function(a, b)
-		local ip_a = Util.ipToNumber(a.name) or 0
+     return ipOps.compare_ip(a, "lt", b)
-		local ip_b = Util.ipToNumber(b.name) or 0
-
-		if ( tonumber(ip_a) < tonumber(ip_b) ) then
-			return true
-		end
-		return false
 	end,
 	
 	--- Function used to compare discovered DNS services so they can be sorted
@@ -229,7 +215,10 @@ Comm = {
 		if status then address = ip	end
 
 		status, ipv6 = Comm.getRecordType( dns.types.AAAA, response, false )
-		if status then address = address .. " " .. ipv6	end
+		if status then
+			address = address or ""
+			address = address .. " " .. ipv6
+		end
 
 		status, txt = Comm.getRecordType( dns.types.TXT, response, true )
 		if status then
@@ -337,7 +326,8 @@ Helper = {
 		local status, response
 		local mcast = self.mcast
 		local port = self.port or 5353
-		local host = mcast and "224.0.0.251" or self.host
+		local family = nmap.address_family()
+		local host = mcast and (family=="inet6" and "ff02::fb" or "224.0.0.251") or self.host
 		local service = service or stdnse.get_script_args('dnssd.services')
 		
 		if ( not(service) ) then

nselib/ipOps.lua

@@ -11,6 +11,7 @@ local tonumber = tonumber
 
 local stdnse   = require "stdnse"
 local bit      = require "bit"
+local bin      = require "bin"
 
 module ( "ipOps" )
 
@@ -126,7 +127,7 @@ end
 --
 -- Note: IPv6 addresses are not supported. Currently, numbers in NSE are
 -- limited to 10^14, and consequently not all IPv6 addresses can be
--- represented.
+-- represented. Consider using <code>ip_to_str</code> for IPv6 addresses.
 -- @param ip  String representing an IPv4 address.  Shortened notation is
 -- permitted.
 -- @usage
@@ -211,7 +212,8 @@ end
 
 
 ---
--- Compares two IP addresses (from the same address family).
+-- Compares two IP addresses. When comparing addresses from different families,
+-- IPv4 addresses will sort before IPv6 addresses.
 -- @param left   String representing an IPv4 or IPv6 address.  Shortened
 -- notation is permitted.
 -- @param op     A comparison operator which may be one of the following
@@ -231,47 +233,36 @@ compare_ip = function( left, op, right )
     return nil, "Error in ipOps.compare_ip: Expected IP address as a string."
   end
 
-  if ( left:match( ":" ) and not right:match( ":" ) ) or ( not left:match( ":" ) and right:match( ":" ) ) then
-    return nil, "Error in ipOps.compare_ip: IP addresses must be from the same address family."
-  end
-
-  if op == "lt" or op == "le" then
-    left, right = right, left
-  elseif op ~= "eq" and op ~= "ge" and op ~= "gt" then
-    return nil, "Error in ipOps.compare_ip: Invalid Operator."
-  end
-
   local err ={}
-  left, err[#err+1] = ip_to_bin( left )
+  left, err[#err+1] = ip_to_str( left )
-  right, err[#err+1] = ip_to_bin( right )
+  right, err[#err+1] = ip_to_str( right )
   if #err > 0 then
     return nil, table.concat( err, " " )
   end
 
-  if # left  ~= # right  then
+  if #left > #right then
-      -- shouldn't happen...
+    left = bin.pack( "CA", 0x06, left )
-      return nil, "Error in ipOps.compare_ip: Binary IP addresses were of different lengths."
+    right = bin.pack( "CA", 0x04, right )
+  elseif #right > #left then
+    right = bin.pack( "CA", 0x06, right )
+    left = bin.pack( "CA", 0x04, left )
   end
 
-  -- equal?
+  if ( op == "eq" ) then
-  if ( op == "eq" or op == "le" or op == "ge" ) and left == right then
+    return ( left == right )
-    return true
+  elseif ( op == "ne" ) then
-  elseif op == "eq" then
+    return ( left ~= right )
-    return false
+  elseif ( op == "le" ) then
+    return ( left <= right )
+  elseif ( op == "ge" ) then
+    return ( left >= right )
+  elseif ( op == "lt" ) then
+    return ( left < right )
+  elseif ( op == "gt" ) then
+    return ( left > right )
   end
 
-  -- starting from the leftmost bit, subtract the bit in right from the bit in left
+  return nil, "Error in ipOps.compare_ip: Invalid Operator."
-  local compare
-  for i = 1, # left , 1 do
-    compare = tonumber( string.sub( left, i, i ) ) - tonumber( string.sub( right, i, i ) )
-    if compare == 1 then
-      return true
-    elseif compare == -1 then
-      return false
-    end
-  end
-  return false
-
 end
 
 
@@ -327,12 +318,15 @@ end
 -- the IPv4 portion is shortened and does not contain a dot, in which case the
 -- address will be treated as IPv6.
 -- @param ip  String representing an IPv4 or IPv6 address in shortened or full notation.
+-- @param family String representing the address family to expand to. Only
+-- affects IPv4 addresses when "inet6" is provided, causing the function to
+-- return an IPv4-mapped IPv6 address.
 -- @usage
 -- local ip = ipOps.expand_ip( "2001::" )
 -- @return    String representing a fully expanded IPv4 or IPv6 address (or
 -- <code>nil</code> in case of an error).
 -- @return String error message in case of an error.
-expand_ip = function( ip )
+expand_ip = function( ip, family )
   local err
 
   if type( ip ) ~= "string" or ip == "" then
@@ -355,7 +349,18 @@ expand_ip = function( ip )
     while #octets < 4 do
       octets[#octets+1] = "0"
     end
-    return ( table.concat( octets, "." ) )
+    if family == "inet6" then
+      return ( table.concat( { 0,0,0,0,0,"ffff",
+        stdnse.tohex( 256*octets[1]+octets[2] ),
+        stdnse.tohex( 256*octets[3]+octets[4] ) 
+        }, ":" ) )
+    else
+      return ( table.concat( octets, "." ) )
+    end
+  end
+
+  if family ~= nil and family ~= "inet6" then
+    return nil, "Error in ipOps.expand_ip: Cannot convert IPv6 address to IPv4"
   end
 
   if ip:match( "[^\.:%x]" ) then
@@ -498,6 +503,39 @@ get_last_ip = function( ip, prefix )
 
 end
 
+---
+-- Converts an IP address into an opaque string.
+-- @param ip  String representing an IPv4 or IPv6 address.
+-- @param family (optional) Address family to convert to. "ipv6" converts IPv4
+-- addresses to IPv4-mapped IPv6.
+-- @usage
+-- opaque = ipOps.ip_to_str( "192.168.3.4" )
+-- @return 4- or 16-byte string representing IP address (or <code>nil</code>
+-- in case of an error).
+-- @return String error message in case of an error
+ip_to_str = function( ip, family )
+  local err
+
+  ip, err = expand_ip( ip, family )
+  if err then return nil, err end
+
+  local t = {}
+
+  if not ip:match( ":" ) then
+    -- ipv4 string
+    for octet in string.gmatch( ip, "%d+" ) do
+      t[#t+1] = bin.pack( ">C", tonumber(octet) )
+    end
+  else
+    -- ipv6 string
+    for hdt in string.gmatch( ip, "%x+" ) do
+      t[#t+1] = bin.pack( ">S", tonumber(hdt, 16) )
+    end
+  end
+
+
+  return table.concat( t )
+end
 
 
 ---

nselib/upnp.lua

@@ -40,30 +40,16 @@ require("target")
 require("http")
 
 Util = {
-	
-	--- Converts a string ip to a numeric value suitable for comparing
-	--
-	-- @param ip string containing the ip to convert
-	-- @return number containing the converted ip
-	ipToNumber = function(ip)
-		local o1, o2, o3, o4 = ip:match("^(%d*)%.(%d*)%.(%d*)%.(%d*)$")
-		return (256^3) * o1 + (256^2) * o2 + (256^1) * o3 + (256^0) * o4
-	end,
 
 	--- Compare function used for sorting IP-addresses
 	--
 	-- @param a table containing first item
 	-- @param b table containing second item
-	-- @return true if the port of a is less than the port of b
+	-- @return true if a is less than b
 	ipCompare = function(a, b)
-		local ip_a = Util.ipToNumber(a.name)
+    return ipOps.compare_ip(a, "lt", b)
-		local ip_b = Util.ipToNumber(b.name)
+	end,
-		if ( tonumber(ip_a) < tonumber(ip_b) ) then
+
-			return true
-		end
-		return false
-	end
-	
 }
 
 Comm = {
@@ -293,7 +279,8 @@ Comm = {
 	setMulticast = function( self, mcast )
 		assert( type(mcast)=="boolean", "mcast has to be either true or false")
 		self.mcast = mcast
-		self.host = "239.255.255.250"
+		local family = nmap.address_family()		
+		self.host = (family=="inet6" and "FF02::C" or "239.255.255.250")
 		self.port = 1900
 	end,
 
@@ -351,4 +338,4 @@ Helper = {
 		return status, response
 	end,
 	
-}
+}

nselib/wsdd.lua

@@ -322,8 +322,10 @@ Helper = {
 	-- @param mcast boolean true if multicast is to be used, false otherwise
 	setMulticast = function( self, mcast )
 		assert( type(mcast)=="boolean", "mcast has to be either true or false")
+		local family = nmap.address_family()
 		self.mcast = mcast
-		self.host, self.port = "239.255.255.250", 3702
+		self.host = (family=="inet6" and "FF02::C" or "239.255.255.250")
+		self.port = 3702
 	end,
 	
 	--- Sets the timeout for socket reads

scripts/ntp-monlist.nse

@@ -1059,8 +1059,9 @@ function output_ips(t)
     end
   end
 
-  -- IPv6 - for now, no sorting.
+  -- IPv6
   -- Rows are allowed to be 71 chars wide
+  table.sort(t['6'], function(a,b) return ipOps.compare_ip(a, "lt", b) end)
   local i = 1
   local limit = #t['6']
   while i <= limit do