New tableaux library containing table auxiliary functions.

scripts/dns-nsec-enum.nse

@@ -4,6 +4,7 @@ local shortport = require "shortport"
 local stdnse = require "stdnse"
 local string = require "string"
 local table = require "table"
+local tableaux = require "tableaux"
 
 description = [[
 Enumerates DNS names using the DNSSEC NSEC-walking technique.
@@ -119,16 +120,6 @@ local function guess_domain(host)
   end
 end
 
-local function invert(t)
-  local result = {}
-
-  for k, v in pairs(t) do
-    result[v] = k
-  end
-
-  return result
-end
-
 -- RFC 952: "A 'name' is a text string up to 24 characters drawn from the
 -- alphabet (A-Z), digits (0-9), minus sign (-), and period (.). ... The first
 -- character must be an alpha character."
@@ -138,7 +129,7 @@ end
 -- RFC 2782: An underscore (_) is prepended to the service identifier to avoid
 -- collisions with DNS labels that occur in nature.
 local DNS_CHARS = { string.byte("-0123456789_abcdefghijklmnopqrstuvwxyz", 1, -1) }
-local DNS_CHARS_INV = invert(DNS_CHARS)
+local DNS_CHARS_INV = tableaux.invert(DNS_CHARS)
 
 -- Return the lexicographically next component, or nil if component is the
 -- lexicographically last.