mirror of
https://github.com/rapid7/metasploit-framework
synced 2024-10-29 18:07:27 +01:00
Move JSObfu a gem then pull it into the Rex namespace.
This commit is contained in:
Joe Vennix
parent
a846d084ca
commit
0f4be63903
@ -5,6 +5,7 @@ PATH
|
||||
actionpack (< 4.0.0)
|
||||
activesupport (>= 3.0.0, < 4.0.0)
|
||||
bcrypt
|
||||
jsobfu (~> 0.1.6)
|
||||
json
|
||||
metasploit-model (~> 0.26.1)
|
||||
meterpreter_bins (= 0.0.7)
|
||||
@ -12,7 +13,6 @@ PATH
|
||||
nokogiri
|
||||
packetfu (= 1.1.9)
|
||||
railties
|
||||
rkelly-remix (= 0.0.6)
|
||||
robots
|
||||
rubyzip (~> 1.1)
|
||||
sqlite3
|
||||
@ -90,6 +90,8 @@ GEM
|
||||
hike (1.2.3)
|
||||
i18n (0.6.11)
|
||||
journey (1.0.4)
|
||||
jsobfu (0.1.6)
|
||||
rkelly-remix (= 0.0.6)
|
||||
json (1.8.1)
|
||||
mail (2.5.4)
|
||||
mime-types (~> 1.16)
|
||||
|
||||
@ -1,513 +1,16 @@
|
||||
# -*- coding: binary -*-
|
||||
|
||||
require 'rex/text'
|
||||
require 'rex/random_identifier_generator'
|
||||
require 'rkelly'
|
||||
require 'jsobfu'
|
||||
|
||||
module Rex
|
||||
module Exploitation
|
||||
|
||||
|
||||
#
|
||||
# Obfuscate JavaScript by randomizing as much as possible and removing
|
||||
# easily-signaturable string constants.
|
||||
# Simple wrapper class that makes the JSObfu functionality
|
||||
# from the gem available under the Rex namespace.
|
||||
#
|
||||
# Example:
|
||||
# js = ::Rex::Exploitation::JSObfu.new %Q|
|
||||
# var a = "0\\612\\063\\x34\\x35\\x36\\x37\\x38\\u0039";
|
||||
# var b = { foo : "foo", bar : "bar" }
|
||||
# alert(a);
|
||||
# alert(b.foo);
|
||||
# |
|
||||
# js.obfuscate
|
||||
# puts js
|
||||
# Example Output:
|
||||
# var VwxvESbCgv = String.fromCharCode(0x30,0x31,062,063,064,53,0x36,067,070,0x39);
|
||||
# var ToWZPn = {
|
||||
# "\146\157\x6f": (function () { var yDyv="o",YnCL="o",Qcsa="f"; return Qcsa+YnCL+yDyv })(),
|
||||
# "\142ar": String.fromCharCode(0142,97,0162)
|
||||
# };
|
||||
# alert(VwxvESbCgv);
|
||||
# alert(ToWZPn.foo);
|
||||
#
|
||||
# NOTE: Variables MUST be declared with a 'var' statement BEFORE first use (or
|
||||
# not at all) for this to generate correct code! If variables are not declared
|
||||
# they will not be randomized but the generated code will be correct.
|
||||
#
|
||||
# Bad Example Javascript:
|
||||
# a = "asdf"; // this variable hasn't been declared and will not be randomized
|
||||
# var a;
|
||||
# alert(a); // real js engines will alert "asdf" here
|
||||
# Bad Example Obfuscated:
|
||||
# a = (function () { var hpHu="f",oyTm="asd"; return oyTm+hpHu })();
|
||||
# var zSrnHpEfJZtg;
|
||||
# alert(zSrnHpEfJZtg);
|
||||
# Notice that the first usage of +a+ (before it was declared) is not
|
||||
# randomized. Thus, the obfuscated version will alert 'undefined' instead of
|
||||
# "asdf".
|
||||
#
|
||||
class JSObfu
|
||||
|
||||
# these keywords should never be used as a random var name
|
||||
# source: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Reserved_Words
|
||||
RESERVED_KEYWORDS = %w(
|
||||
break case catch continue debugger default delete do else finally
|
||||
for function if in instanceof new return switch this throw try
|
||||
typeof var void while with class enum export extends import super
|
||||
implements interface let package private protected public static yield
|
||||
)
|
||||
|
||||
#
|
||||
# Abstract Syntax Tree generated by RKelly::Parser#parse
|
||||
#
|
||||
attr_reader :ast
|
||||
|
||||
#
|
||||
# Saves +code+ for later obfuscation with #obfuscate
|
||||
#
|
||||
def initialize(code)
|
||||
@code = code
|
||||
@funcs = {}
|
||||
@vars = {}
|
||||
@debug = false
|
||||
@rand_gen = Rex::RandomIdentifierGenerator.new(
|
||||
:max_length => 15,
|
||||
:first_char_set => Rex::Text::Alpha+"_$",
|
||||
:char_set => Rex::Text::AlphaNumeric+"_$"
|
||||
)
|
||||
class JSObfu < ::JSObfu
|
||||
end
|
||||
|
||||
#
|
||||
# Add +str+ to the un-obfuscated code.
|
||||
#
|
||||
# Calling this method after #obfuscate is undefined
|
||||
#
|
||||
def <<(str)
|
||||
@code << str
|
||||
end
|
||||
|
||||
#
|
||||
# Return the (possibly obfuscated) code as a string.
|
||||
#
|
||||
# If #obfuscate has not been called before this, returns the parsed,
|
||||
# unobfuscated code. This can be useful for example to remove comments and
|
||||
# standardize spacing.
|
||||
#
|
||||
def to_s
|
||||
parse if not @ast
|
||||
@ast.to_ecma
|
||||
end
|
||||
|
||||
#
|
||||
# Return the obfuscated name of a symbol
|
||||
#
|
||||
# You MUST call #obfuscate before this method!
|
||||
#
|
||||
def sym(lookup)
|
||||
if @vars[lookup]
|
||||
ret = @vars[lookup]
|
||||
elsif @funcs[lookup]
|
||||
ret = @funcs[lookup]
|
||||
else
|
||||
ret = lookup
|
||||
end
|
||||
ret
|
||||
end
|
||||
|
||||
#
|
||||
# Parse and obfuscate
|
||||
#
|
||||
def obfuscate
|
||||
parse
|
||||
obfuscate_r(@ast)
|
||||
end
|
||||
|
||||
# @return [String] a unique random var name that is not a reserved keyword
|
||||
def random_var_name
|
||||
loop do
|
||||
text = random_string
|
||||
unless @vars.has_value?(text) or RESERVED_KEYWORDS.include?(text)
|
||||
return text
|
||||
end
|
||||
end
|
||||
end
|
||||
|
||||
protected
|
||||
|
||||
# @return [String] a random string
|
||||
def random_string
|
||||
@rand_gen.generate
|
||||
end
|
||||
|
||||
#
|
||||
# Recursive method to obfuscate the given +ast+.
|
||||
#
|
||||
# +ast+ should be the result of RKelly::Parser#parse
|
||||
#
|
||||
def obfuscate_r(ast)
|
||||
ast.each do |node|
|
||||
#if node.respond_to? :value and node.value.kind_of? String and node.value =~ /bodyOnLoad/i
|
||||
# $stdout.puts("bodyOnLoad: #{node.class}: #{node.value}")
|
||||
#end
|
||||
|
||||
case node
|
||||
when nil
|
||||
nil
|
||||
|
||||
when ::RKelly::Nodes::SourceElementsNode
|
||||
# Recurse
|
||||
obfuscate_r(node.value)
|
||||
|
||||
#when ::RKelly::Nodes::ObjectLiteralNode
|
||||
# TODO
|
||||
#$stdout.puts(node.methods - Object.new.methods)
|
||||
#$stdout.puts(node.value.inspect)
|
||||
|
||||
when ::RKelly::Nodes::PropertyNode
|
||||
# Property names must be bare words or string literals NOT
|
||||
# expressions! Can't use transform_string() here
|
||||
if node.name =~ /^[a-zA-Z_][a-zA-Z0-9_]*$/
|
||||
n = '"'
|
||||
node.name.unpack("C*") { |c|
|
||||
case rand(3)
|
||||
when 0; n << "\\x%02x"%(c)
|
||||
when 1; n << "\\#{c.to_s 8}"
|
||||
when 2; n << [c].pack("C")
|
||||
end
|
||||
}
|
||||
n << '"'
|
||||
node.instance_variable_set(:@name, n)
|
||||
end
|
||||
|
||||
# Variables
|
||||
when ::RKelly::Nodes::VarDeclNode
|
||||
if @vars[node.name].nil?
|
||||
@vars[node.name] = random_var_name
|
||||
end
|
||||
node.name = @vars[node.name]
|
||||
when ::RKelly::Nodes::ParameterNode
|
||||
if @vars[node.value].nil?
|
||||
@vars[node.value] = random_var_name
|
||||
end
|
||||
node.value = @vars[node.value]
|
||||
when ::RKelly::Nodes::ResolveNode
|
||||
#$stdout.puts("Resolve bodyOnload: #{@vars[node.value]}") if "bodyOnLoad" == node.value
|
||||
node.value = @vars[node.value] if @vars[node.value]
|
||||
when ::RKelly::Nodes::DotAccessorNode
|
||||
case node.value
|
||||
when ::RKelly::Nodes::ResolveNode
|
||||
if @vars[node.value.value]
|
||||
node.value.value = @vars[node.value.value]
|
||||
end
|
||||
#else
|
||||
# $stderr.puts("Non-resolve node as target of dotaccessor: #{node.value.class}")
|
||||
end
|
||||
|
||||
# Functions
|
||||
when ::RKelly::Nodes::FunctionDeclNode
|
||||
#$stdout.puts("FunctionDecl: #{node.value}")
|
||||
# Functions can also act as objects, so store them in the vars
|
||||
# and the functions list so we can replace them in both places
|
||||
if @funcs[node.value].nil? and not @funcs.values.include?(node.value)
|
||||
@funcs[node.value] = random_var_name
|
||||
if @vars[node.value].nil?
|
||||
@vars[node.value] = @funcs[node.value]
|
||||
end
|
||||
node.value = @funcs[node.value]
|
||||
end
|
||||
when ::RKelly::Nodes::FunctionCallNode
|
||||
# The value of a FunctionCallNode is some sort of accessor node or a ResolveNode
|
||||
# so this is basically useless
|
||||
#$stdout.puts("Function call: #{node.name} => #{@funcs[node.name]}")
|
||||
#node.value = @funcs[node.value] if @funcs[node.value]
|
||||
|
||||
# Transformers
|
||||
when ::RKelly::Nodes::NumberNode
|
||||
node.value = transform_number(node.value)
|
||||
when ::RKelly::Nodes::StringNode
|
||||
node.value = transform_string(node.value)
|
||||
else
|
||||
#$stderr.puts "#{node.class}: #{node.value}"
|
||||
#$stderr.puts "#{node.class}"
|
||||
end
|
||||
|
||||
#unless node.kind_of? ::RKelly::Nodes::SourceElementsNode
|
||||
# $stderr.puts "#{node.class}: #{node.value}"
|
||||
#end
|
||||
end
|
||||
|
||||
nil
|
||||
end
|
||||
|
||||
#
|
||||
# Generate an Abstract Syntax Tree (#ast) for later obfuscation
|
||||
#
|
||||
def parse
|
||||
parser = RKelly::Parser.new
|
||||
@ast = parser.parse(@code)
|
||||
end
|
||||
|
||||
#
|
||||
# Convert a number to a random base (decimal, octal, or hexedecimal).
|
||||
#
|
||||
# Given 10 as input, the possible return values are:
|
||||
# "10"
|
||||
# "0xa"
|
||||
# "012"
|
||||
#
|
||||
def rand_base(num)
|
||||
case rand(3)
|
||||
when 0; num.to_s
|
||||
when 1; "0%o" % num
|
||||
when 2; "0x%x" % num
|
||||
end
|
||||
end
|
||||
|
||||
#
|
||||
# Return a mathematical expression that will evaluate to the given number
|
||||
# +num+.
|
||||
#
|
||||
# +num+ can be a float or an int, but should never be negative.
|
||||
#
|
||||
def transform_number(num)
|
||||
case num
|
||||
when Fixnum
|
||||
if num == 0
|
||||
r = rand(10) + 1
|
||||
transformed = "('#{Rex::Text.rand_text_alpha(r)}'.length - #{r})"
|
||||
elsif num > 0 and num < 10
|
||||
# use a random string.length for small numbers
|
||||
transformed = "'#{Rex::Text.rand_text_alpha(num)}'.length"
|
||||
else
|
||||
transformed = "("
|
||||
divisor = rand(num) + 1
|
||||
a = num / divisor.to_i
|
||||
b = num - (a * divisor)
|
||||
# recurse half the time for a
|
||||
a = (rand(2) == 0) ? transform_number(a) : rand_base(a)
|
||||
# recurse half the time for divisor
|
||||
divisor = (rand(2) == 0) ? transform_number(divisor) : rand_base(divisor)
|
||||
transformed << "#{a}*#{divisor}"
|
||||
transformed << "+#{b}"
|
||||
transformed << ")"
|
||||
end
|
||||
when Float
|
||||
transformed = "(#{num - num.floor} + #{rand_base(num.floor)})"
|
||||
end
|
||||
|
||||
#puts("#{num} == #{transformed}")
|
||||
|
||||
transformed
|
||||
end
|
||||
|
||||
#
|
||||
# Convert a javascript string into something that will generate that string.
|
||||
#
|
||||
# Randomly calls one of the +transform_string_*+ methods
|
||||
#
|
||||
def transform_string(str)
|
||||
quote = str[0,1]
|
||||
# pull off the quotes
|
||||
str = str[1,str.length - 2]
|
||||
return quote*2 if str.length == 0
|
||||
|
||||
case rand(2)
|
||||
when 0
|
||||
transformed = transform_string_split_concat(str, quote)
|
||||
when 1
|
||||
transformed = transform_string_fromCharCode(str)
|
||||
#when 2
|
||||
# # Currently no-op
|
||||
# transformed = transform_string_unescape(str)
|
||||
end
|
||||
|
||||
#$stderr.puts "Obfuscating str: #{str.ljust 30} #{transformed}"
|
||||
transformed
|
||||
end
|
||||
|
||||
#
|
||||
# Split a javascript string, +str+, without breaking escape sequences.
|
||||
#
|
||||
# The maximum length of each piece of the string is half the total length
|
||||
# of the string, ensuring we (almost) always split into at least two
|
||||
# pieces. This won't always be true when given a string like "AA\x41",
|
||||
# where escape sequences artificially increase the total length (escape
|
||||
# sequences are considered a single character).
|
||||
#
|
||||
# Returns an array of two-element arrays. The zeroeth element is a
|
||||
# randomly generated variable name, the first is a piece of the string
|
||||
# contained in +quote+s.
|
||||
#
|
||||
# See #escape_length
|
||||
#
|
||||
def safe_split(str, quote)
|
||||
parts = []
|
||||
max_len = str.length / 2
|
||||
while str.length > 0
|
||||
len = 0
|
||||
loop do
|
||||
e_len = escape_length(str[len..-1])
|
||||
e_len = 1 if e_len.nil?
|
||||
len += e_len
|
||||
# if we've reached the end of the string, bail
|
||||
break unless str[len]
|
||||
break if len > max_len
|
||||
# randomize the length of each part
|
||||
break if (rand(4) == 0)
|
||||
end
|
||||
|
||||
part = str.slice!(0, len)
|
||||
|
||||
var = Rex::Text.rand_text_alpha(4)
|
||||
parts.push( [ var, "#{quote}#{part}#{quote}" ] )
|
||||
end
|
||||
|
||||
parts
|
||||
end
|
||||
|
||||
#
|
||||
# Stolen from obfuscatejs.rb
|
||||
#
|
||||
# Determines the length of an escape sequence
|
||||
#
|
||||
def escape_length(str)
|
||||
esc_len = nil
|
||||
if str[0,1] == "\\"
|
||||
case str[1,1]
|
||||
when "u"; esc_len = 6 # unicode \u1234
|
||||
when "x"; esc_len = 4 # hex, \x41
|
||||
when /[0-7]/ # octal, \123, \0
|
||||
str[1,3] =~ /([0-7]{1,3})/
|
||||
if $1.to_i(8) > 255
|
||||
str[1,3] =~ /([0-7]{1,2})/
|
||||
end
|
||||
esc_len = 1 + $1.length
|
||||
else; esc_len = 2 # \" \n, etc.
|
||||
end
|
||||
end
|
||||
esc_len
|
||||
end
|
||||
|
||||
#
|
||||
# Split a javascript string, +str+, into multiple randomly-ordered parts
|
||||
# and return an anonymous javascript function that joins them in the
|
||||
# correct order. This method can be called safely on strings containing
|
||||
# escape sequences. See #safe_split.
|
||||
#
|
||||
def transform_string_split_concat(str, quote)
|
||||
parts = safe_split(str, quote)
|
||||
func = "(function () { var "
|
||||
ret = "; return "
|
||||
parts.sort { |a,b| rand }.each do |part|
|
||||
func << "#{part[0]}=#{part[1]},"
|
||||
end
|
||||
func.chop!
|
||||
|
||||
ret << parts.map{|part| part[0]}.join("+")
|
||||
final = func + ret + " })()"
|
||||
|
||||
final
|
||||
end
|
||||
|
||||
|
||||
# TODO
|
||||
#def transform_string_unescape(str)
|
||||
# str
|
||||
#end
|
||||
|
||||
#
|
||||
# Return a call to String.fromCharCode() with each char of the input as arguments
|
||||
#
|
||||
# Example:
|
||||
# input : "A\n"
|
||||
# output: String.fromCharCode(0x41, 10)
|
||||
#
|
||||
def transform_string_fromCharCode(str)
|
||||
buf = "String.fromCharCode("
|
||||
bytes = str.unpack("C*")
|
||||
len = 0
|
||||
while str.length > 0
|
||||
if str[0,1] == "\\"
|
||||
str.slice!(0,1)
|
||||
# then this is an escape sequence and we need to deal with all
|
||||
# the special cases
|
||||
case str[0,1]
|
||||
# For chars that contain their non-escaped selves, step past
|
||||
# the backslash and let the rand_base() below decide how to
|
||||
# represent the character.
|
||||
when '"', "'", "\\", " "
|
||||
char = str.slice!(0,1).unpack("C").first
|
||||
# For symbolic escapes, use the known value
|
||||
when "n"; char = 0x0a; str.slice!(0,1)
|
||||
when "t"; char = 0x09; str.slice!(0,1)
|
||||
# Lastly, if it's a hex, unicode, or octal escape, pull out the
|
||||
# real value and use that
|
||||
when "x"
|
||||
# Strip the x
|
||||
str.slice!(0,1)
|
||||
char = str.slice!(0,2).to_i 16
|
||||
when "u"
|
||||
# This can potentially lose information in the case of
|
||||
# characters like \u0041, but since regular ascii is stored
|
||||
# as unicode internally, String.fromCharCode(0x41) will be
|
||||
# represented as 00 41 in memory anyway, so it shouldn't
|
||||
# matter.
|
||||
str.slice!(0,1)
|
||||
char = str.slice!(0,4).to_i 16
|
||||
when /[0-7]/
|
||||
# Octals are a bit harder since they are variable width and
|
||||
# don't necessarily mean what you might think. For example,
|
||||
# "\61" == "1" and "\610" == "10". 610 is a valid octal
|
||||
# number, but not a valid ascii character. Javascript will
|
||||
# interpreter as much as it can as a char and use the rest
|
||||
# as a literal. Boo.
|
||||
str =~ /([0-7]{1,3})/
|
||||
char = $1.to_i 8
|
||||
if char > 255
|
||||
str =~ /([0-7]{1,2})/
|
||||
char = $1.to_i 8
|
||||
end
|
||||
str.slice!(0,$1.length)
|
||||
end
|
||||
else
|
||||
char = str.slice!(0,1).unpack("C").first
|
||||
end
|
||||
buf << "#{rand_base(char)},"
|
||||
end
|
||||
# Strip off the last comma
|
||||
buf = buf[0,buf.length-1] + ")"
|
||||
transformed = buf
|
||||
|
||||
transformed
|
||||
end
|
||||
|
||||
|
||||
end
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
=begin
|
||||
if __FILE__ == $0
|
||||
if ARGV[0]
|
||||
code = File.read(ARGV[0])
|
||||
else
|
||||
#require 'rex/exploitation/javascriptosdetect'
|
||||
#code = Rex::Exploitation::JavascriptOSDetect.new.to_s
|
||||
code = <<-EOS
|
||||
// Should alert "0123456789"
|
||||
var a = "0\\612\\063\\x34\\x35\\x36\\x37\\x38\\u0039";
|
||||
var a,b=2,c=3;
|
||||
alert(a);
|
||||
// should alert "asdfjkl;"
|
||||
var d = (function() { var foo = "jkl;", blah = "asdf"; return blah + foo; })();
|
||||
alert(d);
|
||||
EOS
|
||||
end
|
||||
js = Rex::Exploitation::JSObfu.new(code)
|
||||
js.obfuscate
|
||||
puts js.to_s
|
||||
|
||||
end
|
||||
|
||||
=end
|
||||
|
||||
@ -55,6 +55,8 @@ Gem::Specification.new do |spec|
|
||||
spec.add_runtime_dependency 'actionpack', rails_version_constraint
|
||||
# Needed for some admin modules (cfme_manageiq_evm_pass_reset.rb)
|
||||
spec.add_runtime_dependency 'bcrypt'
|
||||
# Needed for Javascript obfuscation
|
||||
spec.add_runtime_dependency 'jsobfu', '~> 0.1.6'
|
||||
# Needed for some admin modules (scrutinizer_add_user.rb)
|
||||
spec.add_runtime_dependency 'json'
|
||||
# Things that would normally be part of the database model, but which
|
||||
@ -70,8 +72,6 @@ Gem::Specification.new do |spec|
|
||||
spec.add_runtime_dependency 'packetfu', '1.1.9'
|
||||
# Run initializers for metasploit-concern, metasploit-credential, metasploit_data_models Rails::Engines
|
||||
spec.add_runtime_dependency 'railties'
|
||||
# Needed by JSObfu
|
||||
spec.add_runtime_dependency 'rkelly-remix', '0.0.6'
|
||||
# Needed by anemone crawler
|
||||
spec.add_runtime_dependency 'robots'
|
||||
# Needed by some modules
|
||||
|
||||
Loading…
Reference in New Issue
Block a user