#!/usr/bin/env ruby # -*- coding: binary -*- # # Check (recursively) for style compliance violations and other # tree inconsistencies. # # by jduck, todb, and friends # require 'fileutils' require 'find' require 'time' CHECK_OLD_RUBIES = !!ENV['MSF_CHECK_OLD_RUBIES'] SUPPRESS_INFO_MESSAGES = !!ENV['MSF_SUPPRESS_INFO_MESSAGES'] TITLE_WHITELIST = %w{ a an and as at avserve callmenum configdir connect debug docbase dtspcd execve file for from getinfo goaway gsad hetro historysearch htpasswd ibstat id in inetd iseemedia jhot libxslt lmgrd lnk load main map migrate mimencode multisort name net netcat nodeid ntpd nttrans of on onreadystatechange or ovutil path pbot pfilez pgpass pingstr pls popsubfolders prescan readvar relfile rev rexec rlogin rsh rsyslog sa sadmind say sblistpack spamd sreplace tagprinter the tnftp to twikidraw udev uplay user username via welcome with ypupdated zsudo } if CHECK_OLD_RUBIES require 'rvm' warn "This is going to take a while, depending on the number of Rubies you have installed." end class String def red "\e[1;31;40m#{self}\e[0m" end def yellow "\e[1;33;40m#{self}\e[0m" end def green "\e[1;32;40m#{self}\e[0m" end def cyan "\e[1;36;40m#{self}\e[0m" end def ascii_only? self =~ Regexp.new('[\x00-\x08\x0b\x0c\x0e-\x19\x7f-\xff]', nil, 'n') ? false : true end end class Msftidy # Status codes OK = 0x00 WARNINGS = 0x10 ERRORS = 0x20 # Some compiles regexes REGEX_MSF_EXPLOIT = / \< Msf::Exploit/ REGEX_IS_BLANK_OR_END = /^\s*end\s*$/ attr_reader :full_filepath, :source, :stat, :name, :status def initialize(source_file) @full_filepath = source_file @module_type = File.dirname(File.expand_path(@full_filepath))[/\/modules\/([^\/]+)/, 1] @source = load_file(source_file) @lines = @source.lines # returns an enumerator @status = OK @name = File.basename(source_file) end public # # Display a warning message, given some text and a number. Warnings # are usually style issues that may be okay for people who aren't core # Framework developers. # # @return status [Integer] Returns WARNINGS unless we already have an # error. def warn(txt, line=0) line_msg = (line>0) ? ":#{line}" : '' puts "#{@full_filepath}#{line_msg} - [#{'WARNING'.yellow}] #{cleanup_text(txt)}" @status == ERRORS ? @status = ERRORS : @status = WARNINGS end # # Display an error message, given some text and a number. Errors # can break things or are so egregiously bad, style-wise, that they # really ought to be fixed. # # @return status [Integer] Returns ERRORS def error(txt, line=0) line_msg = (line>0) ? ":#{line}" : '' puts "#{@full_filepath}#{line_msg} - [#{'ERROR'.red}] #{cleanup_text(txt)}" @status = ERRORS end # Currently unused, but some day msftidy will fix errors for you. def fixed(txt, line=0) line_msg = (line>0) ? ":#{line}" : '' puts "#{@full_filepath}#{line_msg} - [#{'FIXED'.green}] #{cleanup_text(txt)}" end # # Display an info message. Info messages do not alter the exit status. # def info(txt, line=0) return if SUPPRESS_INFO_MESSAGES line_msg = (line>0) ? ":#{line}" : '' puts "#{@full_filepath}#{line_msg} - [#{'INFO'.cyan}] #{cleanup_text(txt)}" end ## # # The functions below are actually the ones checking the source code # ## def check_mode unless (@stat.mode & 0111).zero? warn("Module should not be marked executable") end end def check_shebang if @lines.first =~ /^#!/ warn("Module should not have a #! line") end end # Updated this check to see if Nokogiri::XML.parse is being called # specifically. The main reason for this concern is that some versions # of libxml2 are still vulnerable to XXE attacks. REXML is safer (and # slower) since it's pure ruby. Unfortunately, there is no pure Ruby # HTML parser (except Hpricot which is abandonware) -- easy checks # can avoid Nokogiri (most modules use regex anyway), but more complex # checks tends to require Nokogiri for HTML element and value parsing. def check_nokogiri msg = "Using Nokogiri in modules can be risky, use REXML instead." has_nokogiri = false has_nokogiri_xml_parser = false @lines.each do |line| if has_nokogiri if line =~ /Nokogiri::XML\.parse/ or line =~ /Nokogiri::XML::Reader/ has_nokogiri_xml_parser = true break end else has_nokogiri = line_has_require?(line, 'nokogiri') end end error(msg) if has_nokogiri_xml_parser end def check_ref_identifiers in_super = false in_refs = false @lines.each do |line| if !in_super and line =~ /\s+super\(/ in_super = true elsif in_super and line =~ /[[:space:]]*def \w+[\(\w+\)]*/ in_super = false break end if in_super and line =~ /["']References["'][[:space:]]*=>/ in_refs = true elsif in_super and in_refs and line =~ /^[[:space:]]+\],*/m break elsif in_super and in_refs and line =~ /[^#]+\[[[:space:]]*['"](.+)['"][[:space:]]*,[[:space:]]*['"](.+)['"][[:space:]]*\]/ identifier = $1.strip.upcase value = $2.strip case identifier when 'CVE' warn("Invalid CVE format: '#{value}'") if value !~ /^\d{4}\-\d{4,}$/ when 'OSVDB' warn("Invalid OSVDB format: '#{value}'") if value !~ /^\d+$/ when 'BID' warn("Invalid BID format: '#{value}'") if value !~ /^\d+$/ when 'MSB' warn("Invalid MSB format: '#{value}'") if value !~ /^MS\d+\-\d+$/ when 'MIL' warn("milw0rm references are no longer supported.") when 'EDB' warn("Invalid EDB reference") if value !~ /^\d+$/ when 'US-CERT-VU' warn("Invalid US-CERT-VU reference") if value !~ /^\d+$/ when 'ZDI' warn("Invalid ZDI reference") if value !~ /^\d{2}-\d{3}$/ when 'WPVDB' warn("Invalid WPVDB reference") if value !~ /^\d+$/ when 'PACKETSTORM' warn("Invalid PACKETSTORM reference") if value !~ /^\d+$/ when 'URL' if value =~ /^http:\/\/www\.osvdb\.org/ warn("Please use 'OSVDB' for '#{value}'") elsif value =~ /^http:\/\/cvedetails\.com\/cve/ warn("Please use 'CVE' for '#{value}'") elsif value =~ /^http:\/\/www\.securityfocus\.com\/bid\// warn("Please use 'BID' for '#{value}'") elsif value =~ /^http:\/\/www\.microsoft\.com\/technet\/security\/bulletin\// warn("Please use 'MSB' for '#{value}'") elsif value =~ /^http:\/\/www\.exploit\-db\.com\/exploits\// warn("Please use 'EDB' for '#{value}'") elsif value =~ /^http:\/\/www\.kb\.cert\.org\/vuls\/id\// warn("Please use 'US-CERT-VU' for '#{value}'") elsif value =~ /^https:\/\/wpvulndb\.com\/vulnerabilities\// warn("Please use 'WPVDB' for '#{value}'") elsif value =~ /^https?:\/\/(?:[^\.]+\.)?packetstormsecurity\.(?:com|net|org)\// warn("Please use 'PACKETSTORM' for '#{value}'") end end end end end # See if 'require "rubygems"' or equivalent is used, and # warn if so. Since Ruby 1.9 this has not been necessary and # the framework only suports 1.9+ def check_rubygems @lines.each do |line| if line_has_require?(line, 'rubygems') warn("Explicitly requiring/loading rubygems is not necessary") break end end end # Does the given line contain a require/load of the specified library? def line_has_require?(line, lib) line =~ /^\s*(require|load)\s+['"]#{lib}['"]/ end def check_snake_case_filename sep = File::SEPARATOR good_name = Regexp.new "^[a-z0-9_#{sep}]+\.rb$" unless @name =~ good_name warn "Filenames should be alphanum and snake case." end end def check_comment_splat if @source =~ /^# This file is part of the Metasploit Framework and may be subject to/ warn("Module contains old license comment.") end end def check_old_keywords max_count = 10 counter = 0 if @source =~ /^##/ @lines.each do |line| # If exists, the $Id$ keyword should appear at the top of the code. # If not (within the first 10 lines), then we assume there's no # $Id$, and then bail. break if counter >= max_count if line =~ /^#[[:space:]]*\$Id\$/i warn("Keyword $Id$ is no longer needed.") break end counter += 1 end end if @source =~ /["']Version["'][[:space:]]*=>[[:space:]]*['"]\$Revision\$['"]/ warn("Keyword $Revision$ is no longer needed.") end end def check_verbose_option if @source =~ /Opt(Bool|String).new\([[:space:]]*('|")VERBOSE('|")[[:space:]]*,[[:space:]]*\[[[:space:]]*/ warn("VERBOSE Option is already part of advanced settings, no need to add it manually.") end end def check_badchars badchars = %Q|&<=>| in_super = false in_author = false @lines.each do |line| # # Mark our "super" code block # if !in_super and line =~ /\s+super\(/ in_super = true elsif in_super and line =~ /[[:space:]]*def \w+[\(\w+\)]*/ in_super = false break end # # While in super() code block # if in_super and line =~ /["']Name["'][[:space:]]*=>[[:space:]]*['|"](.+)['|"]/ # Now we're checking the module titlee mod_title = $1 mod_title.each_char do |c| if badchars.include?(c) error("'#{c}' is a bad character in module title.") end end if not mod_title.ascii_only? error("Please avoid unicode or non-printable characters in module title.") end # Since we're looking at the module title, this line clearly cannot be # the author block, so no point to run more code below. next end # XXX: note that this is all very fragile and regularly incorrectly parses # the author # # Mark our 'Author' block # if in_super and !in_author and line =~ /["']Author["'][[:space:]]*=>/ in_author = true elsif in_super and in_author and line =~ /\],*\n/ or line =~ /['"][[:print:]]*['"][[:space:]]*=>/ in_author = false end # # While in 'Author' block, check for malformed authors # if in_super and in_author if line =~ /Author['"]\s*=>\s*['"](.*)['"],/ author_name = Regexp.last_match(1) elsif line =~ /Author/ author_name = line.scan(/\[[[:space:]]*['"](.+)['"]/).flatten[-1] || '' else author_name = line.scan(/['"](.+)['"]/).flatten[-1] || '' end if author_name =~ /^@.+$/ error("No Twitter handles, please. Try leaving it in a comment instead.") end if not author_name.ascii_only? error("Please avoid unicode or non-printable characters in Author") end unless author_name.empty? author_open_brackets = author_name.scan('<').size author_close_brackets = author_name.scan('>').size if author_open_brackets != author_close_brackets error("Author has unbalanced brackets: #{author_name}") end end end end end def check_extname if File.extname(@name) != '.rb' error("Module should be a '.rb' file, or it won't load.") end end def check_old_rubies return true unless CHECK_OLD_RUBIES return true unless Object.const_defined? :RVM puts "Checking syntax for #{@name}." rubies ||= RVM.list_strings res = %x{rvm all do ruby -c #{@full_filepath}}.split("\n").select {|msg| msg =~ /Syntax OK/} error("Fails alternate Ruby version check") if rubies.size != res.size end def is_exploit_module? ret = false if @source =~ REGEX_MSF_EXPLOIT # having Msf::Exploit is good indicator, but will false positive on # specs and other files containing the string, but not really acting # as exploit modules, so here we check the file for some actual contents # this could be done in a simpler way, but this let's us add more later msf_exploit_line_no = nil @lines.each_with_index do |line, idx| if line =~ REGEX_MSF_EXPLOIT # note the line number msf_exploit_line_no = idx elsif msf_exploit_line_no # check there is anything but empty space between here and the next end # something more complex could be added here if line !~ REGEX_IS_BLANK_OR_END # if the line is not 'end' and is not blank, prolly exploit module ret = true break else # then keep checking in case there are more than one Msf::Exploit msf_exploit_line_no = nil end end end end ret end def check_ranking return unless is_exploit_module? available_ranks = [ 'ManualRanking', 'LowRanking', 'AverageRanking', 'NormalRanking', 'GoodRanking', 'GreatRanking', 'ExcellentRanking' ] if @source =~ /Rank \= (\w+)/ if not available_ranks.include?($1) error("Invalid ranking. You have '#{$1}'") end else info('No Rank specified. The default is NormalRanking. Please add an explicit Rank value.') end end def check_disclosure_date return if @source =~ /Generic Payload Handler/ # Check disclosure date format if @source =~ /["']DisclosureDate["'].*\=\>[\x0d\x20]*['\"](.+)['\"]/ d = $1 #Captured date # Flag if overall format is wrong if d =~ /^... \d{1,2}\,* \d{4}/ # Flag if month format is wrong m = d.split[0] months = [ 'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec' ] error('Incorrect disclosure month format') if months.index(m).nil? else error('Incorrect disclosure date format') end else error('Exploit is missing a disclosure date') if is_exploit_module? end end def check_title_casing if @source =~ /["']Name["'][[:space:]]*=>[[:space:]]*['"](.+)['"],*$/ words = $1.split words.each do |word| if TITLE_WHITELIST.include?(word) next elsif word =~ /^[a-z]+$/ warn("Suspect capitalization in module title: '#{word}'") end end end end def check_bad_terms # "Stack overflow" vs "Stack buffer overflow" - See explanation: # http://blogs.technet.com/b/srd/archive/2009/01/28/stack-overflow-stack-exhaustion-not-the-same-as-stack-buffer-overflow.aspx if @module_type == 'exploit' && @source.gsub("\n", "") =~ /stack[[:space:]]+overflow/i warn('Contains "stack overflow" You mean "stack buffer overflow"?') elsif @module_type == 'auxiliary' && @source.gsub("\n", "") =~ /stack[[:space:]]+overflow/i warn('Contains "stack overflow" You mean "stack exhaustion"?') end end def check_bad_super_class # skip payloads, as they don't have a super class return if @module_type == 'payloads' # get the super class in an ugly way unless (super_class = @source.scan(/class Metasploit(?:\d|Module)\s+<\s+(\S+)/).flatten.first) error('Unable to determine super class') return end prefix_super_map = { 'auxiliary' => /^Msf::Auxiliary$/, 'exploits' => /^Msf::Exploit(?:::Local|::Remote)?$/, 'encoders' => /^(?:Msf|Rex)::Encoder/, 'nops' => /^Msf::Nop$/, 'post' => /^Msf::Post$/ } if prefix_super_map.key?(@module_type) unless super_class =~ prefix_super_map[@module_type] error("Invalid super class for #{@module_type} module (found '#{super_class}', expected something like #{prefix_super_map[@module_type]}") end else warn("Unexpected and potentially incorrect super class found ('#{super_class}')") end end def check_function_basics functions = @source.scan(/def (\w+)\(*(.+)\)*/) functions.each do |func_name, args| # Check argument length args_length = args.split(",").length warn("Poorly designed argument list in '#{func_name}()'. Try a hash.") if args_length > 6 end end def check_bad_class_name if @source =~ /^\s*class (Metasploit\d+)\s* 1) and (ln =~ /^([\t ]*)/) and ($1.match(/\x20\x09|\x09\x20/)) warn("Space-Tab mixed indent: #{ln.inspect}", idx) end # Check for tabs. Upgrade this to an error() soon. if (ln.length > 1) and (ln =~ /^\x09/) warn("Tabbed indent: #{ln.inspect}", idx) end if ln =~ /\r$/ warn("Carriage return EOL", idx) end url_ok = false if ln =~ /\.com\/projects\/Framework/ if ln =~ /File\.open/ and ln =~ /[\"\'][arw]/ if not ln =~ /[\"\'][wra]\+?b\+?[\"\']/ warn("File.open without binary mode", idx) end end if ln =~/^[ \t]*load[ \t]+[\x22\x27]/ error("Loading (not requiring) a file: #{ln.inspect}", idx) end # The rest of these only count if it's not a comment line next if ln =~ /^[[:space:]]*#/ if ln =~ /\$std(?:out|err)/i or ln =~ /[[:space:]]puts/ next if ln =~ /^[\s]*["][^"]+\$std(?:out|err)/ no_stdio = false error("Writes to stdout", idx) end # do not read Set-Cookie header (ignore commented lines) if ln =~ /^(?!\s*#).+\[['"]Set-Cookie['"]\](?!\s*=[^=~]+)/i warn("Do not read Set-Cookie header directly, use res.get_cookies instead: #{ln}", idx) end # Auxiliary modules do not have a rank attribute if ln =~ /^\s*Rank\s*=\s*/ && @module_type == 'auxiliary' warn("Auxiliary modules have no 'Rank': #{ln}", idx) end if ln =~ /^\s*def\s+(?:[^\(\)#]*[A-Z]+[^\(\)]*)(?:\(.*\))?$/ warn("Please use snake case on method names: #{ln}", idx) end if ln =~ /^\s*fail_with\(/ unless ln =~ /^\s*fail_with\(Failure\:\:(?:None|Unknown|Unreachable|BadConfig|Disconnected|NotFound|UnexpectedReply|TimeoutExpired|UserInterrupt|NoAccess|NoTarget|NotVulnerable|PayloadFailed),/ error("fail_with requires a valid Failure:: reason as first parameter: #{ln}", idx) end end if ln =~ /['"]ExitFunction['"]\s*=>/ warn("Please use EXITFUNC instead of ExitFunction #{ln}", idx) end end end def check_vuln_codes checkcode = @source.scan(/(Exploit::)?CheckCode::(\w+)/).flatten[1] if checkcode and checkcode !~ /^Unknown|Safe|Detected|Appears|Vulnerable|Unsupported$/ error("Unrecognized checkcode: #{checkcode}") end end def check_vars_get test = @source.scan(/send_request_cgi\s*\(\s*\{?\s*['"]uri['"]\s*=>\s*[^=})]*?\?[^,})]+/im) unless test.empty? test.each { |item| info("Please use vars_get in send_request_cgi: #{item}") } end end def check_newline_eof if @source !~ /(?:\r\n|\n)\z/m info('Please add a newline at the end of the file') end end def check_sock_get if @source =~ /\s+sock\.get(\s*|\(|\d+\s*|\d+\s*,\d+\s*)/m && @source !~ /sock\.get_once/ info('Please use sock.get_once instead of sock.get') end end def check_udp_sock_get if @source =~ /udp_sock\.get/m && @source !~ /udp_sock\.get\([a-zA-Z0-9]+/ info('Please specify a timeout to udp_sock.get') end end # At one point in time, somebody committed a module with a bad metasploit.com URL # in the header -- http//metasploit.com/download rather than http://metasploit.com/download. # This module then got copied and committed 20+ times and is used in numerous other places. # This ensures that this stops. def check_invalid_url_scheme test = @source.scan(/^#.+http\/\/(?:www\.)?metasploit.com/) unless test.empty? test.each { |item| info("Invalid URL: #{item}") } end end # Check for (v)print_debug usage, since it doesn't exist anymore # # @see https://github.com/rapid7/metasploit-framework/issues/3816 def check_print_debug if @source =~ /print_debug/ error('Please don\'t use (v)print_debug, use vprint_(status|good|error|warning) instead') end end # Check for modules registering the DEBUG datastore option # # @see https://github.com/rapid7/metasploit-framework/issues/3816 def check_register_datastore_debug if @source =~ /Opt.*\.new\(["'](?i)DEBUG(?-i)["']/ error('Please don\'t register a DEBUG datastore option, it has an special meaning and is used for development') end end # Check for modules using the DEBUG datastore option # # @see https://github.com/rapid7/metasploit-framework/issues/3816 def check_use_datastore_debug if @source =~ /datastore\[["'](?i)DEBUG(?-i)["']\]/ error('Please don\'t use the DEBUG datastore option in production, it has an special meaning and is used for development') end end # # Run all the msftidy checks. # def run_checks check_mode check_shebang check_nokogiri check_rubygems check_ref_identifiers check_old_keywords check_verbose_option check_badchars check_extname check_old_rubies check_ranking check_disclosure_date check_title_casing check_bad_terms check_bad_super_class check_bad_class_name check_function_basics check_lines check_snake_case_filename check_comment_splat check_vuln_codes check_vars_get check_newline_eof check_sock_get check_udp_sock_get check_invalid_url_scheme check_print_debug check_register_datastore_debug check_use_datastore_debug end private def load_file(file) f = open(file, 'rb') @stat = f.stat buf = f.read(@stat.size) f.close return buf end def cleanup_text(txt) # remove line breaks txt = txt.gsub(/[\r\n]/, ' ') # replace multiple spaces by one space txt.gsub(/\s{2,}/, ' ') end end ## # # Main program # ## if __FILE__ == $PROGRAM_NAME dirs = ARGV @exit_status = 0 if dirs.length < 1 $stderr.puts "Usage: #{File.basename(__FILE__)} " @exit_status = 1 exit(@exit_status) end dirs.each do |dir| begin Find.find(dir) do |full_filepath| next if full_filepath =~ /\.git[\x5c\x2f]/ next unless File.file? full_filepath next unless full_filepath =~ /\.rb$/ msftidy = Msftidy.new(full_filepath) msftidy.run_checks @exit_status = msftidy.status if (msftidy.status > @exit_status.to_i) end rescue Errno::ENOENT $stderr.puts "#{File.basename(__FILE__)}: #{dir}: No such file or directory" end end exit(@exit_status.to_i) end