Merge branch 'master' of /Users/dmaloney/rapid7/filtered-framework

lib/rex/rop_builder/rop.rb

@@ -0,0 +1,271 @@
+# -*- coding: binary -*-
+require 'metasm'
+require 'rex/compat'
+require 'rex/text/table'
+require 'rex/ui/text/output/stdio'
+require 'rex/text/color'
+
+module Rex
+module RopBuilder
+
+class RopBase
+  def initialize()
+    @stdio = Rex::Ui::Text::Output::Stdio.new
+    @gadgets = []
+  end
+
+  def to_csv(gadgets = [])
+    if gadgets.empty? and @gadgets.nil? or @gadgets.empty?
+      @stdio.print_error("No gadgets collected to convert to CSV format.")
+      return
+    end
+
+    # allow the users to import gadget collections from multiple files
+    if @gadgets.empty? or @gadgets.nil?
+      @gadgets = gadgets
+    end
+
+    table = Rex::Text::Table.new(
+    'Header'    => "#{@file} ROP Gadgets",
+    'Indent'    => 1,
+    'Columns'   =>
+    [
+      "Address",
+      "Raw",
+      "Disassembly",
+    ])
+
+    @gadgets.each do |gadget|
+      table << [gadget[:address], gadget[:raw].unpack('H*')[0], gadget[:disasm].gsub(/\n/, ' | ')]
+    end
+
+    return table.to_csv
+  end
+
+  def import(file)
+    begin
+      data = File.new(file, 'r').read
+    rescue
+      @stdio.print_error("Error reading #{file}")
+      return []
+    end
+
+    if data.empty? or data.nil?
+      return []
+    end
+
+    data.gsub!(/\"/, '')
+    data.gsub!("Address,Raw,Disassembly\n", '')
+
+    @gadgets = []
+
+    data.each_line do |line|
+      addr, raw, disasm = line.split(',', 3)
+      if addr.nil? or raw.nil? or disasm.nil?
+        @stdio.print_error("Import file format corrupted")
+        return []
+      end
+      disasm.gsub!(/: /, ":\t")
+      disasm.gsub!(' | ', "\n")
+      raw = [raw].pack('H*')
+      @gadgets << {:file => file, :address => addr, :raw => raw, :disasm => disasm.chomp!}
+    end
+      @gadgets
+  end
+
+  def print_msg(msg, color=true)
+    if not @stdio
+      @stdio = Rex::Ui::Text::Output::Stdio.new
+    end
+
+    if color == true
+      @stdio.auto_color
+    else
+        @stdio.disable_color
+    end
+    @stdio.print_raw(@stdio.substitute_colors(msg))
+  end
+end
+
+class RopCollect < RopBase
+  def initialize(file="")
+    @stdio = Rex::Ui::Text::Output::Stdio.new
+    @file = file if not file.empty?
+    @bin = Metasm::AutoExe.decode_file(file) if not file.empty?
+    @disassembler = @bin.disassembler if not @bin.nil?
+    if @disassembler
+      @disassembler.cpu = Metasm::Ia32.new('386_common')
+    end
+    super()
+  end
+
+  def collect(depth, pattern)
+    matches = []
+    gadgets = []
+
+    # find matches by scanning for the pattern
+    matches = @disassembler.pattern_scan(pattern)
+    if @bin.kind_of?(Metasm::PE)
+      @bin.sections.each do |section|
+        next if section.characteristics.include? 'MEM_EXECUTE'
+        # delete matches if the address is outside the virtual address space
+        matches.delete_if do |ea|
+          va = section.virtaddr + @bin.optheader.image_base
+          ea >= va and ea < va + section.virtsize
+        end
+      end
+    elsif @bin.kind_of?(Metasm::ELF)
+      @bin.segments.each do |seg|
+        next if seg.flags.include? 'X'
+        matches.delete_if do |ea|
+          ea >= seg.vaddr and ea < seg.vaddr + seg.memsz
+        end
+      end
+    elsif @bin.kind_of?(Metasm::MachO)
+      @bin.segments.each do |seg|
+        next if seg.initprot.include? 'EXECUTE'
+        matches.delete_if do |ea|
+          ea >= seg.virtaddr and ea < seg.virtaddr + seg.filesize
+        end
+      end
+    end
+
+    gadgets = process_gadgets(matches, depth)
+    gadgets.each do |gadget|
+      @gadgets << gadget
+    end
+    gadgets
+  end
+
+  def pattern_search(pattern)
+    p = Regexp.new("(" + pattern + ")")
+    matches = []
+
+    @gadgets.each do |gadget|
+      disasm = ""
+      addrs = []
+
+      gadget[:disasm].each_line do |line|
+        addr, asm = line.split("\t", 2)
+        addrs << addr
+        disasm << asm
+      end
+
+      if gadget[:raw] =~ p or gadget[:disasm] =~ p or disasm =~ p
+        matches << {:gadget => gadget, :disasm => disasm, :addrs => addrs}
+      end
+    end
+    matches.each do |match|
+      @stdio.print_status("gadget with address: %bld%cya#{match[:gadget][:address]}%clr matched")
+      color_pattern(match[:gadget], match[:disasm], match[:addrs], p)
+    end
+    matches
+  end
+
+  def color_pattern(gadget, disasm, addrs, p)
+    idx = disasm.index(p)
+    if idx.nil?
+      print_msg(gadget[:disasm])
+      return
+    end
+
+    disasm = disasm.insert(idx, "%bld%grn")
+
+    asm = ""
+    cnt = 0
+    colors = false
+    disasm.each_line do |line|
+      # if we find this then we are in the matching area
+      if line.index(/\%bld\%grn/)
+        colors = true
+      end
+      asm << "%clr" + addrs[cnt] + "\t"
+
+      # color the remaining parts of the gadget
+      if colors and line.index("%bld%grn").nil?
+        asm << "%bld%grn" + line
+      else
+        asm << line
+      end
+
+      cnt += 1
+    end
+    asm << "%clr\n"
+    print_msg(asm)
+  end
+
+  def process_gadgets(rets, num)
+    ret     = {}
+    gadgets = []
+    tmp     = []
+    rets.each do |ea|
+      insn = @disassembler.disassemble_instruction(ea)
+      next if not insn
+
+      xtra = insn.bin_length
+
+      num.downto(0) do |x|
+        addr = ea - x
+
+        # get the disassembled instruction at this address
+        di = @disassembler.disassemble_instruction(addr)
+
+        # skip invalid instructions
+        next if not di
+        next if di.opcode.props[:setip]
+        next if di.opcode.props[:stopexec]
+
+        # get raw bytes
+        buf = @disassembler.read_raw_data(addr, x + xtra)
+
+
+        # make sure disassembling forward leads to our instruction
+        next if not ends_with_addr(buf, addr, ea)
+
+        dasm = ""
+        while addr <= ea
+          di = @disassembler.disassemble_instruction(addr)
+          dasm << ("0x%08x:\t" % addr) + di.instruction.to_s + "\n"
+          addr = addr + di.bin_length
+        end
+
+        if not tmp.include?(ea)
+          tmp << ea
+        else
+          next
+        end
+
+        # otherwise, we create a new tailchunk and add it to the list
+        ret = {:file => @file, :address => ("0x%08x" % (ea - x)), :raw => buf, :disasm => dasm}
+        gadgets << ret
+      end
+    end
+    gadgets
+  end
+
+  private
+  def ends_with_addr(raw, base, addr)
+    dasm2 = Metasm::Shellcode.decode(raw, @disassembler.cpu).disassembler
+    offset = 0
+    while ((di = dasm2.disassemble_instruction(offset)))
+      return true if (base + offset) == addr
+      return false if di.opcode.props[:setip]
+      return false if di.opcode.props[:stopexec]
+      offset = di.next_addr
+    end
+    false
+  end
+
+  def raw_instructions(raw)
+    insns = []
+    d2 = Metasm::Shellcode.decode(raw, @disassembler.cpu).disassembler
+    addr = 0
+    while ((di = d2.disassemble_instruction(addr)))
+      insns << di.instruction
+      addr = di.next_addr
+    end
+    insns
+  end
+end
+end
+end