---
-- Read and parse some of Nmap's data files: <code>nmap-protocols</code>,
-- <code>nmap-rpc</code>, <code>nmap-services</code>, and
-- <code>nmap-mac-prefixes</code>.
--
-- The functions in this module return values appropriate for use with exception
-- handling via <code>nmap.new_try</code>. On success, they return true and
-- the function result. On failure, they return false and an error message.
-- @author Kris Katterjohn 03/2008
-- @author jah 08/2008
-- @copyright Same as Nmap--See http://nmap.org/book/man-legal.html
local io = require "io"
local nmap = require "nmap"
local stdnse = require "stdnse"
local string = require "string"
local table = require "table"
_ENV = stdnse.module("datafiles", stdnse.seeall)
---
-- Capture patterns for common data files, indexed by filename.
-- @class table
-- @name common_files
-- @see parse_file
local common_files = {
["nmap-rpc"] = { [function(ln) return tonumber( ln:match( "^%s*[^%s#]+%s+(%d+)" ) ) end] = "^%s*([^%s#]+)%s+%d+" },
["nmap-protocols"] = { [function(ln) return tonumber( ln:match( "^%s*[^%s#]+%s+(%d+)" ) ) end] = "^%s*([^%s#]+)%s+%d+" },
["nmap-services"] = { ["tcp"] = { [function(ln) return tonumber( ln:match( "^%s*[^%s#]+%s+(%d+)/tcp" ) ) end] = "^%s*([^%s#]+)%s+%d+/tcp" },
["udp"] = { [function(ln) return tonumber( ln:match( "^%s*[^%s#]+%s+(%d+)/udp" ) ) end] = "^%s*([^%s#]+)%s+%d+/udp" }
},
["nmap-mac-prefixes"] = { [ "^%s*(%w+)%s+[^#]+" ] = "^%s*%w+%s+([^#]+)" }
}
-- Helper for parse_* functions
local parse_and_cache = function(filename)
nmap.registry.datafiles = nmap.registry.datafiles or {}
if not nmap.registry.datafiles[filename] then
local status
status, nmap.registry.datafiles[filename] = parse_file(filename)
if not status then
return false, string.format("Error parsing %s", filename)
end
end
return true, nmap.registry.datafiles[filename]
end
---
-- Read and parse <code>nmap-protocols</code>.
--
-- On success, return true and a table mapping protocol numbers to protocol
-- names.
-- @return Status (true or false).
-- @return Table (if status is true) or error string (if status is false).
-- @see parse_file
parse_protocols = function()
return parse_and_cache("nmap-protocols")
end
---
-- Read and parse <code>nmap-rpc</code>.
--
-- On success, return true and a table mapping RPC numbers to RPC names.
-- @return Status (true or false).
-- @return Table (if status is true) or error string (if status is false).
-- @see parse_file
parse_rpc = function()
return parse_and_cache("nmap-rpc")
end
---
-- Read and parse <code>nmap-services</code>.
--
-- On success, return true and a table containing two subtables, indexed by the
-- keys "tcp" and "udp". The <code>tcp</code> subtable maps TCP port numbers to
-- service names, and the <code>udp</code> subtable is the same for UDP. You can
-- pass "tcp" or "udp" as an argument to <code>parse_services</code> to get
-- only one of the results tables.
-- @param protocol The protocol table to return (<code>"tcp"</code> or
-- <code>"udp"</code>).
-- @return Status (true or false).
-- @return Table (if status is true) or error string (if status is false).
-- @see parse_file
parse_services = function(protocol)
if protocol and protocol ~= "tcp" and protocol ~= "udp" then
return false, "Bad protocol for nmap-services: use tcp or udp"
end
local services_table
nmap.registry.datafiles = nmap.registry.datafiles or {}
nmap.registry.datafiles.services = nmap.registry.datafiles.services or {}
if protocol then
if not nmap.registry.datafiles.services[protocol] then
local status
status, nmap.registry.datafiles.services[protocol] = parse_file("nmap-services", protocol)
if not status then
return false, "Error parsing nmap-services"
end
end
services_table = nmap.registry.datafiles.services[protocol]
else
local status
status, nmap.registry.datafiles.services = parse_file("nmap-services")
if not status then
return false, "Error parsing nmap-services"
end
services_table = nmap.registry.datafiles.services
end
return true, services_table
end
---
-- Read and parse <code>nmap-mac-prefixes</code>.
--
-- On success, return true and a table mapping 3 byte MAC prefixes to manufacturer names.
-- @return Status (true or false).
-- @return Table (if status is true) or error string (if status is false).
-- @see parse_file
parse_mac_prefixes = function()
return parse_and_cache("nmap-mac-prefixes")
end
---
-- Read and parse a generic data file. The other parse functions are
-- defined in terms of this one.
--
-- If filename is a key in <code>common_files</code>, use the corresponding
-- capture pattern. Otherwise the second argument must be a table of the kind
-- taken by <code>parse_lines</code>.
-- @param filename Name of the file to parse.
-- @param ... A table of capture patterns.
-- @return A table whose structure mirrors that of the capture table,
-- filled in with captured values.
function parse_file(filename, ...)
local data_struct
-- must have a filename
if type( filename ) ~= "string" or filename == "" then
return false, "Error in datafiles.parse_file: No file to parse."
end
-- is filename a member of common_files? is second parameter a key in common_files or is it a table?
if common_files[filename] and type( (...) ) == "string" and common_files[filename][(...)] then
data_struct = { common_files[filename][(...)] }
elseif common_files[filename] and select("#", ...) == 0 then
data_struct = { common_files[filename] }
elseif type( (...) ) == "table" then
data_struct = {...}
elseif type( (...) ) ~= "table" then
return false, "Error in datafiles.parse_file: Expected second parameter as table."
end
if type( data_struct ) == "table" then
for i, struc in ipairs( data_struct ) do
-- check that all varargs are tables
if type( struc ) ~= "table" then return false, "Error in datafiles.parse_file: Bad Parameter." end
-- allow empty table as sugar for ^(.+)$ capture the whole line
if not next( struc ) and #struc == 0 then data_struct[i] = { "^(.+)$" } end
end
if #data_struct == 0 then
return false, "Error in datafiles.parse_file: I've no idea how you want your data."
end
end
-- get a table of lines
local status, lines = read_from_file( filename )
if not status then
return false, ( "Error in datafiles.parse_file: %s could not be read: %s." ):format( filename, lines )
end
-- do the actual parsing
local ret = {}
for _, ds in ipairs( data_struct ) do
status, ret[#ret+1] = parse_lines( lines, ds )
-- hmmm should we fail all if there are any failures? yes? ok
if not status then return false, ret[#ret] end
end
return true, table.unpack( ret )
end
---
-- Generic parsing of an array of strings.
-- @param lines An array of strings to operate on.
-- @param data_struct A table containing capture patterns to be applied
-- to each string in the array. A capture will be applied to each string
-- using <code>string.match</code> and may also be enclosed within a table or
-- a function. If a function, it must accept a string as its parameter and
-- should return one value derived from that string.
-- @return A table whose structure mirrors that of the capture table,
-- filled in with captured values.
function parse_lines(lines, data_struct)
if type( lines ) ~= "table" or #lines < 1 then
return false, "Error in datafiles.parse_lines: No lines to parse."
end
if type( data_struct ) ~= "table" or not next( data_struct ) then
return false, "Error in datafiles.parse_lines: Expected second parameter as a non-empty table."
end
local ret = {}
-- traverse data_struct and enforce sensible index-value pairs. Call functions to process the members of lines.
for index, value in pairs( data_struct ) do
if type(index) == nil then return false, "Error in datafiles.parse_lines: Invalid index." end
if type(index) == "number" or type(value) == "table" then
if type(value) == "number" then
return false, "Error in datafiles.parse_lines: No patterns for data capture."
elseif type(value) == "string" or type(value) == "function" then
ret = get_array( lines, value )
elseif type(value) == "table" then
local _
_, ret[index] = parse_lines( lines, value )
else
-- TEMP
stdnse.print_debug( "Error in datafiles.parse_lines: Index with type %s has unexpected value %s", type(index), type(value))
end
elseif type(index) == "string" or type(index) == "function" then
if type( value ) == "string" or type( value ) == "function" then
ret = get_assoc_array( lines, index, value )
else
return false, ( "Error in datafiles.parse_lines: Invalid value for index %s." ):format( index )
end
else
-- TEMP
stdnse.print_debug( "Error in datafiles.parse_lines: Index with type %s has unexpected value %s", type(index), type(value))
end
end
return true, ret
end
---
-- Read a file, line by line, into a table.
-- @param file String with the name of the file to read.
-- @return Status (true or false).
-- @return Array of lines read from the file (if status is true) or error
-- message (if status is false).
function read_from_file( file )
-- get path to file
local filepath = nmap.fetchfile( file )
if not filepath then
return false, ( "Error in nmap.fetchfile: Could not find file %s." ):format( file )
end
local f, err, _ = io.open( filepath, "r" )
if not f then
return false, ( "Error in datafiles.read_from_file: Cannot open %s for reading: %s" ):format( filepath, err )
end
local ret = {}
for line in f:lines() do
ret[#ret+1] = line
end
f:close()
return true, ret
end
---
-- Return an array-like table of values captured from each line.
-- @param lines Table of strings containing the lines to process.
-- @param v_pattern Pattern to use on the lines to produce the value for the
-- array.
get_array = function(lines, v_pattern)
local ret = {}
for _, line in ipairs( lines ) do
assert( type( line ) == "string" )
local captured
if type( v_pattern ) == "function" then
captured = v_pattern( line )
else
captured = line:match( v_pattern )
end
table.insert( ret, captured )
end
return ret
end
---
-- Return a table of index-value pairs captured from each line.
-- @param lines Table of strings containing the lines to process.
-- @param i_pattern Pattern to use on the lines to produce the key for the
-- associative array.
-- @param v_pattern Pattern to use on the lines to produce the value for the
-- associative array.
get_assoc_array = function(lines, i_pattern, v_pattern)
local ret = {}
for _, line in ipairs(lines) do
assert( type( line ) == "string" )
local index
if type(i_pattern) == "function" then
index = i_pattern(line)
else
index = line:match(i_pattern)
end
if index and type(v_pattern) == "function" then
local m = v_pattern(line)
if m then ret[index] = m end
elseif index then
local m = line:match(v_pattern)
if m then ret[index] = m end
end
end
return ret
end
return _ENV;
@KyuuKazami