diff --git a/scripts/dns-zone-transfer.nse b/scripts/dns-zone-transfer.nse
index 52e0a8239..80c57efbc 100644
--- a/scripts/dns-zone-transfer.nse
+++ b/scripts/dns-zone-transfer.nse
@@ -75,16 +75,16 @@ license = "Same as Nmap--See http://nmap.org/book/man-legal.html"
 categories = {'default', 'intrusive', 'discovery'}
 
 prerule = function() return true end
-portrule = shortport.portnumber(53, 'tcp') 
+portrule = shortport.portnumber(53, 'tcp')
 
 --- DNS query and response types.
 --@class table
 --@name typetab
-local typetab = { 'A', 'NS', 'MD', 'MF', 'CNAME', 'SOA', 'MB', 'MG', 'MR', 
+local typetab = { 'A', 'NS', 'MD', 'MF', 'CNAME', 'SOA', 'MB', 'MG', 'MR',
  'NULL', 'WKS', 'PTR', 'HINFO', 'MINFO', 'MX', 'TXT', 'RP', 'AFSDB', 'X25',
  'ISDN', 'RT', 'NSAP', 'NSAP-PTR', 'SIG', 'KEY', 'PX', 'GPOS', 'AAAA', 'LOC',
  'NXT', 'EID', 'NIMLOC', 'SRV', 'ATMA', 'NAPTR', 'KX', 'CERT', 'A6', 'DNAME',
- 'SINK', 'OPT', [250]='TSIG', [251]='IXFR', [252]='AXFR', [253]='MAILB', 
+ 'SINK', 'OPT', [250]='TSIG', [251]='IXFR', [252]='AXFR', [253]='MAILB',
  [254]='MAILA', [255]='ANY', [256]='ZXFR'
 }
 
@@ -109,217 +109,217 @@ local tld = {
  'sb','sc','sd','se','sg','sh','si','sj','sk','sl','sm','sn','so','sr','st','su',
  'sv','sy','sz','tc','td','tf','tg','th','tj','tk','tl','tm','tn','to','tp','tr',
  'tt','tv','tw','tz','ua','ug','uk','um','us','uy','uz','va','vc','ve','vg','vi',
- 'vn','vu','wf','ws','ye','yt','yu','za','zm','zw' 
+ 'vn','vu','wf','ws','ye','yt','yu','za','zm','zw'
 }
 
---- Convert two bytes into a 16bit number. 
+--- Convert two bytes into a 16bit number.
 --@param data String of data.
 --@param idx Index in the string (first of two consecutive bytes).
 --@return 16 bit number represented by the two bytes.
 function bto16(data, idx)
-	local b1 = string.byte(data, idx)
-	local b2 = string.byte(data, idx+1)
-	-- (b2 & 0xff) | ((b1 & 0xff) << 8)
-	return bit.bor(bit.band(b2, 255), bit.lshift(bit.band(b1, 255), 8))
+    local b1 = string.byte(data, idx)
+    local b2 = string.byte(data, idx+1)
+    -- (b2 & 0xff) | ((b1 & 0xff) << 8)
+    return bit.bor(bit.band(b2, 255), bit.lshift(bit.band(b1, 255), 8))
 end
 
 --- Check if domain name element is a tld
 --@param elm Domain name element to check.
 --@return boolean
 function valid_tld(elm)
-	for i,v in ipairs(tld) do
-		if elm == v then return true end
-	end
-	return false
+    for i,v in ipairs(tld) do
+        if elm == v then return true end
+    end
+    return false
 end
 
 --- Parse an RFC 1035 domain name.
 --@param data String of data.
 --@param offset Offset in the string to read the domain name.
 function parse_domain(data, offset)
-	local offset, domain = dns.decStr(data, offset)
-	domain = domain or "<parse error>"
-	return offset, domain
-end 
+    local offset, domain = dns.decStr(data, offset)
+    domain = domain or "<parse error>"
+    return offset, domain
+end
 
 --- Build RFC 1035 root domain name from the name of the DNS server
 --  (e.g ns1.website.com.ar -> \007website\003com\002ar\000).
 --@param host The host.
 function build_domain(host)
-	local names, buf, x 
-	local abs_name, i, tmp 
+    local names, buf, x
+    local abs_name, i, tmp
 
-	buf = strbuf.new()
-	abs_name = {}
+    buf = strbuf.new()
+    abs_name = {}
 
-	names = stdnse.strsplit('%.', host)
-	if names == nil then names = {host} end
-	
-	-- try to determine root of domain name
-	for i, x in ipairs(listop.reverse(names)) do
-		table.insert(abs_name, x)
-		if not valid_tld(x) then break end
-	end
-	
-	i = 1
-	abs_name = listop.reverse(abs_name)
+    names = stdnse.strsplit('%.', host)
+    if names == nil then names = {host} end
 
-	-- prepend each element with its length
-	while i <= table.getn(abs_name) do
-		buf = buf .. string.char(string.len(abs_name[i])) .. abs_name[i]
-		i = i + 1
-	end
+    -- try to determine root of domain name
+    for i, x in ipairs(listop.reverse(names)) do
+        table.insert(abs_name, x)
+        if not valid_tld(x) then break end
+    end
 
-	buf = buf .. '\000'
-	return strbuf.dump(buf) 
+    i = 1
+    abs_name = listop.reverse(abs_name)
+
+    -- prepend each element with its length
+    while i <= table.getn(abs_name) do
+        buf = buf .. string.char(string.len(abs_name[i])) .. abs_name[i]
+        i = i + 1
+    end
+
+    buf = buf .. '\000'
+    return strbuf.dump(buf)
 end
 
 --- Retrieve type specific data (rdata) from dns packets
 function get_rdata(data, offset, ttype)
-	local field, info, i
+    local field, info, i
 
-	info = strbuf.new()
-	info = info .. ''
+    info = strbuf.new()
+    info = info .. ''
 
-	if typetab[ttype] == nil then
-		return offset, ''
+    if typetab[ttype] == nil then
+        return offset, ''
 
-	elseif typetab[ttype] == 'SOA' then
-		-- name server
-		offset, field = parse_domain(data, offset)	
-		info = info .. field;
-		-- mail box
-		offset, field = parse_domain(data, offset)	
-		info = info .. field;
-		-- ignore other values
-		offset = offset + 20 
+    elseif typetab[ttype] == 'SOA' then
+        -- name server
+        offset, field = parse_domain(data, offset)
+        info = info .. field;
+        -- mail box
+        offset, field = parse_domain(data, offset)
+        info = info .. field;
+        -- ignore other values
+        offset = offset + 20
 
-	elseif typetab[ttype] == 'MX' then
-		-- mail server
-		offset = offset + 2
-		offset, field = parse_domain(data, offset)
-		info = info .. field
+    elseif typetab[ttype] == 'MX' then
+        -- mail server
+        offset = offset + 2
+        offset, field = parse_domain(data, offset)
+        info = info .. field
 
-	elseif typetab[ttype] == 'A' then
-		-- ip address
-		info = info .. 
-		string.byte(data, offset) .. '.' ..
-		string.byte(data, offset+1) .. '.' ..
-		string.byte(data, offset+2) .. '.' ..
-		string.byte(data, offset+3)
-		offset = offset + 4
+    elseif typetab[ttype] == 'A' then
+        -- ip address
+        info = info ..
+        string.byte(data, offset) .. '.' ..
+        string.byte(data, offset+1) .. '.' ..
+        string.byte(data, offset+2) .. '.' ..
+        string.byte(data, offset+3)
+        offset = offset + 4
 
-	elseif typetab[ttype] == 'PTR' or
+    elseif typetab[ttype] == 'PTR' or
                typetab[ttype] == 'NS' then
-		-- domain/domain server name
-		offset, field = parse_domain(data, offset)	
-		info = info .. field;
-	end
+        -- domain/domain server name
+        offset, field = parse_domain(data, offset)
+        info = info .. field;
+    end
 
-	return offset, strbuf.dump(info, ' ')
+    return offset, strbuf.dump(info, ' ')
 end
 
 --- Get a single answer record from the current offset
 function get_answer_record(table, data, offset)
-	local line, rdlen, ttype
-	
-	-- answer domain
-	offset, line = parse_domain(data, offset)
-	tab.add(table, 1, line)
+    local line, rdlen, ttype
 
-	-- answer record type
-	ttype = bto16(data, offset)
-	if not(typetab[ttype] == nil) then
-		tab.add(table, 2, typetab[ttype])
-	end
+    -- answer domain
+    offset, line = parse_domain(data, offset)
+    tab.add(table, 1, line)
 
-	-- length of type specific data
-	rdlen = bto16(data, offset+8)
+    -- answer record type
+    ttype = bto16(data, offset)
+    if not(typetab[ttype] == nil) then
+        tab.add(table, 2, typetab[ttype])
+    end
 
-	-- extra data, ignore ttl and class
-	offset, line =  get_rdata(data, offset+10, ttype)
-	if(line == '') then
-		offset = offset + rdlen
-	else
-		tab.add(table, 3, line)
-	end
+    -- length of type specific data
+    rdlen = bto16(data, offset+8)
 
-	return offset, tab
+    -- extra data, ignore ttl and class
+    offset, line =  get_rdata(data, offset+10, ttype)
+    if(line == '') then
+        offset = offset + rdlen
+    else
+        tab.add(table, 3, line)
+    end
+
+    return offset, tab
 end
 
 function parse_records(number, data, table, offset)
-	while number > 0 do
-		tab.nextrow(table)
-		offset = get_answer_record(table, data, offset)
-		number = number - 1
-	end
-	return offset
+    while number > 0 do
+        tab.nextrow(table)
+        offset = get_answer_record(table, data, offset)
+        number = number - 1
+    end
+    return offset
 end
 
 -- An iterator that breaks up a concatentation of responses. In DNS over TCP,
 -- each response is prefixed by a two-byte length (RFC 1035 section 4.2.2).
 -- Responses returned by this iterator include the two-byte length prefix.
 function responses_iter(data)
-	local offset = 1
+    local offset = 1
 
-	return function()
-		local length, remaining, response
+    return function()
+        local length, remaining, response
 
-		remaining = string.len(data) - offset + 1
-		if remaining == 0 then
-			return nil
-		end
-		assert(remaining >= 14 + 2)
-		length = bto16(data, offset)
-		assert(length <= remaining)
-		-- Skip over the length field.
-		offset = offset + 2
-		response = string.sub(data, offset, offset + length - 1)
-		offset = offset + length
-		return response
-	end
+        remaining = string.len(data) - offset + 1
+        if remaining == 0 then
+            return nil
+        end
+        assert(remaining >= 14 + 2)
+        length = bto16(data, offset)
+        assert(length <= remaining)
+        -- Skip over the length field.
+        offset = offset + 2
+        response = string.sub(data, offset, offset + length - 1)
+        offset = offset + length
+        return response
+    end
 end
 
 function dump_zone_info(table, data)
-	local answers, line, offset
-	local questions, auth_answers, add_answers
-	
-	offset = 1
-	-- number of available records
-	questions = bto16(data, offset+4)
-	answers = bto16(data, offset+6)
-	auth_answers = bto16(data, offset+8)
-	add_answers = bto16(data, offset+10)
+    local answers, line, offset
+    local questions, auth_answers, add_answers
 
-	-- move to beginning of first section
-	offset = offset + 12
+    offset = 1
+    -- number of available records
+    questions = bto16(data, offset+4)
+    answers = bto16(data, offset+6)
+    auth_answers = bto16(data, offset+8)
+    add_answers = bto16(data, offset+10)
 
-	if questions > 1 then
-		return 'More then 1 question record, something has gone wrong'
-	end
+    -- move to beginning of first section
+    offset = offset + 12
 
-	if answers == 0 then
-		return 'transfer successful but no records'
-	end
+    if questions > 1 then
+        return 'More then 1 question record, something has gone wrong'
+    end
 
-	-- skip over the question section, we don't need it
-	if questions == 1 then
-		offset, line = parse_domain(data, offset)
-		offset = offset + 4
-	end
-		
-	-- parse all available resource records
-	offset = parse_records(answers, data, table, offset)
-	offset = parse_records(auth_answers, data, table, offset)
-	offset = parse_records(add_answers, data, table, offset)
-	return offset
+    if answers == 0 then
+        return 'transfer successful but no records'
+    end
+
+    -- skip over the question section, we don't need it
+    if questions == 1 then
+        offset, line = parse_domain(data, offset)
+        offset = offset + 4
+    end
+
+    -- parse all available resource records
+    offset = parse_records(answers, data, table, offset)
+    offset = parse_records(auth_answers, data, table, offset)
+    offset = parse_records(add_answers, data, table, offset)
+    return offset
 end
 
 action = function(host, port)
     local soc, status, data
     local catch = function() soc:close() end
     local try = nmap.new_try(catch)
-    
+
     local args = nmap.registry.args
 
     local domain, dns_server, dns_port = stdnse.get_script_args(
@@ -333,78 +333,77 @@ action = function(host, port)
 
     -- script running at the Script Pre-scanning phase.
     if SCRIPT_TYPE == "prerule" then
-      if not domain then
-      	stdnse.print_debug(3,
-      	  "Skipping '%s' %s, 'dnszonetransfer.domain' argument is missing.",
-      	  SCRIPT_NAME, SCRIPT_TYPE)
-        return
-      end
-      if not dns_server then
-      	stdnse.print_debug(3,
-      	  "Skipping '%s' %s, 'dnszonetransfer.server' argument is missing.",
-      	  SCRIPT_NAME, SCRIPT_TYPE)
-        return
-      end
-    -- script running at the Script Scan phase.
-    elseif SCRIPT_TYPE == "portrule" then
-      if not domain then
-        if host.targetname then
-          domain = host.targetname
-        elseif host.name ~= "" then
-          domain = host.name
-        else
-          -- can't do anything without a hostname
-          return stdnse.format_output(false,
-              string.format("'%s' script needs a dnszonetransfer.domain argument.",
-                  SCRIPT_TYPE))
+        if not domain then
+            stdnse.print_debug(3,
+                "Skipping '%s' %s, 'dnszonetransfer.domain' argument is missing.",
+                SCRIPT_NAME, SCRIPT_TYPE)
+            return
         end
-      end
-      dns_server = host.ip
-      dns_port = port.number
+        if not dns_server then
+            stdnse.print_debug(3,
+                "Skipping '%s' %s, 'dnszonetransfer.server' argument is missing.",
+                SCRIPT_NAME, SCRIPT_TYPE)
+            return
+        end
+        -- script running at the Script Scan phase.
+    elseif SCRIPT_TYPE == "portrule" then
+        if not domain then
+            if host.targetname then
+                domain = host.targetname
+            elseif host.name ~= "" then
+                domain = host.name
+            else
+                -- can't do anything without a hostname
+                return stdnse.format_output(false,
+                string.format("'%s' script needs a dnszonetransfer.domain argument.", SCRIPT_TYPE))
+            end
+        end
+        dns_server = host.ip
+        dns_port = port.number
     end
 
-	assert(domain)
+    assert(domain)
 
-	soc = nmap.new_socket()
-	soc:set_timeout(4000)
-	try(soc:connect(dns_server, dns_port))
+    soc = nmap.new_socket()
+    soc:set_timeout(4000)
+    try(soc:connect(dns_server, dns_port))
 
-	local req_id = '\222\173'
-	local table = tab.new(3)
-	local offset = 1 
-	local name = build_domain(string.lower(domain))
-	local pkt_len = string.len(name) + 16
+    local req_id = '\222\173'
+    local table = tab.new(3)
+    local offset = 1
+    local name = build_domain(string.lower(domain))
+    local pkt_len = string.len(name) + 16
 
-	-- build axfr request
-	local buf = strbuf.new()
-	buf = buf .. '\000' .. string.char(pkt_len) .. req_id 	
-	buf = buf .. '\000\000\000\001\000\000\000\000\000\000'
-	buf = buf .. name .. '\000\252\000\001'
-	try(soc:send(strbuf.dump(buf)))
+    -- build axfr request
+    local buf = strbuf.new()
+    buf = buf .. '\000' .. string.char(pkt_len) .. req_id
+    buf = buf .. '\000\000\000\001\000\000\000\000\000\000'
+    buf = buf .. name .. '\000\252\000\001'
+    try(soc:send(strbuf.dump(buf)))
 
-	-- read all data returned. Common to have 
-	-- multiple packets from a single request
-	local response = strbuf.new()
-	while true do
-		status, data = soc:receive_bytes(1)
-		if not status then break end
-		response = response .. data 
-	end
+    -- read all data returned. Common to have
+    -- multiple packets from a single request
+    local response = strbuf.new()
+    while true do
+        status, data = soc:receive_bytes(1)
+        if not status then break end
+        response = response .. data
+    end
 
-	local response_str = strbuf.dump(response)
-	local length = string.len(response_str)
+    local response_str = strbuf.dump(response)
+    local length = string.len(response_str)
 
-	-- check server response code
-	if length < 6 or 
-           not (bit.band(string.byte(response_str, 6), 15) == 0) then
-		return nil
-	end
+    -- check server response code
+    if length < 6 or
+            not (bit.band(string.byte(response_str, 6), 15) == 0) then
+        return nil
+    end
 
-	-- parse zone information from all returned packets
-	for r in responses_iter(response_str) do
-		dump_zone_info(table, r)
-	end
+    -- parse zone information from all returned packets
+    for r in responses_iter(response_str) do
+        dump_zone_info(table, r)
+    end
 
-	soc:close()
-	return '\n' .. tab.dump(table)
+    soc:close()
+    return '\n' .. tab.dump(table)
 end