Class: Msf::Sessions::CommandShell

Inherits:
Object
  • Object
show all
Includes:
Msf::Session::Basic, Msf::Session::Provider::SingleCommandShell, Msf::Session::Scriptable
Defined in:
lib/msf/base/sessions/command_shell.rb

Overview

This class provides basic interaction with a command shell on the remote endpoint. This session is initialized with a stream that will be used as the pipe for reading and writing the command shell.

Direct Known Subclasses

CommandShellUnix, CommandShellWindows

Instance Attribute Summary collapse

Attributes included from Msf::Session::Interactive

#ring, #rstream

Attributes included from Rex::Ui::Interactive

#completed, #interacting, #on_command_proc, #on_print_proc

Attributes included from Rex::Ui::Subscriber::Input

#user_input

Attributes included from Rex::Ui::Subscriber::Output

#user_output

Attributes included from Msf::Session

#alive, #db_record, #exploit, #exploit_datastore, #exploit_task, #exploit_uuid, #framework, #info, #routes, #sid, #sname, #target_host, #target_port, #username, #uuid, #workspace

Attributes included from Framework::Offspring

#framework

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Msf::Session::Scriptable

#execute_script, included

Methods included from Msf::Session::Provider::SingleCommandShell

#set_shell_token_index, #shell_command_token, #shell_command_token_unix, #shell_command_token_win32, #shell_read_until_token

Methods included from Msf::Session::Interactive

#cleanup, #interactive?, #kill, #tunnel_local, #tunnel_peer

Methods included from Rex::Ui::Interactive

#detach, #interact

Methods included from Rex::Ui::Subscriber

#copy_ui, #init_ui, #reset_ui

Methods included from Rex::Ui::Subscriber::Input

#gets

Methods included from Rex::Ui::Subscriber::Output

#flush, #print, #print_debug, #print_error, #print_good, #print_line, #print_status, #print_warning

Methods included from Msf::Session

#alive?, #cleanup, #dead?, #inspect, #interactive?, #kill, #log_file_name, #log_from_local, #log_from_remote, #log_source, #name, #name=, #register?, #session_host, #session_host=, #session_port, #session_port=, #set_from_exploit, #set_via, #tunnel_local, #tunnel_peer, #tunnel_to_s, #via_exploit, #via_payload

Constructor Details

#initialize(*args) ⇒ CommandShell

Returns a new instance of CommandShell.


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# File 'lib/msf/base/sessions/command_shell.rb', line 50

def initialize(*args)
  self.platform ||= ""
  self.arch     ||= ""
  super
end

Instance Attribute Details

#arch ⇒ Object

Returns the value of attribute arch


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# File 'lib/msf/base/sessions/command_shell.rb', line 236

def arch
  @arch
end

#platform ⇒ Object

Returns the value of attribute platform


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# File 'lib/msf/base/sessions/command_shell.rb', line 237

def platform
  @platform
end

Class Method Details

.type ⇒ Object

Returns the type of session.


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# File 'lib/msf/base/sessions/command_shell.rb', line 46

def self.type
  "shell"
end

Instance Method Details

#desc ⇒ Object

Returns the session description.


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# File 'lib/msf/base/sessions/command_shell.rb', line 59

def desc
  "Command shell"
end

#execute_file(full_path, args) ⇒ Object

:category: Msf::Session::Scriptable implementors

Executes the supplied script, must be specified as full path.

Msf::Session::Scriptable implementor


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# File 'lib/msf/base/sessions/command_shell.rb', line 38

def execute_file(full_path, args)
  o = Rex::Script::Shell.new(self, full_path)
  o.run(args)
end

#process_autoruns(datastore) ⇒ Object

Execute any specified auto-run scripts for this session


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# File 'lib/msf/base/sessions/command_shell.rb', line 204

def process_autoruns(datastore)
  # Read the initial output and mash it into a single line
  if (not self.info or self.info.empty?)
    initial_output = shell_read(-1, 0.01)
    if (initial_output)
      initial_output.force_encoding("ASCII-8BIT") if initial_output.respond_to?(:force_encoding)
      initial_output.gsub!(/[\x00-\x08\x0b\x0c\x0e-\x19\x7f-\xff]+/n,"_")
      initial_output.gsub!(/[\r\n\t]+/, ' ')
      initial_output.strip!

      # Set the inital output to .info
      self.info = initial_output
    end
  end

  if (datastore['InitialAutoRunScript'] && datastore['InitialAutoRunScript'].empty? == false)
    args = Shellwords.shellwords( datastore['InitialAutoRunScript'] )
    print_status("Session ID #{sid} (#{tunnel_to_s}) processing InitialAutoRunScript '#{datastore['InitialAutoRunScript']}'")
    execute_script(args.shift, *args)
  end

  if (datastore['AutoRunScript'] && datastore['AutoRunScript'].empty? == false)
    args = Shellwords.shellwords( datastore['AutoRunScript'] )
    print_status("Session ID #{sid} (#{tunnel_to_s}) processing AutoRunScript '#{datastore['AutoRunScript']}'")
    execute_script(args.shift, *args)
  end
end

#reset_ring_sequence ⇒ Object 


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# File 'lib/msf/base/sessions/command_shell.rb', line 232

def reset_ring_sequence
  self.ring_seq = 0
end

#run_cmd(cmd) ⇒ Object

Explicitly runs a command.


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# File 'lib/msf/base/sessions/command_shell.rb', line 66

def run_cmd(cmd)
  shell_command(cmd)
end

#shell_close ⇒ Object

:category: Msf::Session::Provider::SingleCommandShell implementors

Closes the shell.


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# File 'lib/msf/base/sessions/command_shell.rb', line 196

def shell_close()
  rstream.close rescue nil
  self.kill
end

#shell_command(cmd) ⇒ Object

:category: Msf::Session::Provider::SingleCommandShell implementors

Explicitly run a single command, return the output.


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# File 'lib/msf/base/sessions/command_shell.rb', line 91

def shell_command(cmd)
  # Send the command to the session's stdin.
  shell_write(cmd + "\n")

  timeo = 5
  etime = ::Time.now.to_f + timeo
  buff = ""

  # Keep reading data until no more data is available or the timeout is
  # reached.
  while (::Time.now.to_f < etime and (self.respond_to?(:ring) or ::IO.select([rstream], nil, nil, timeo)))
    res = shell_read(-1, 0.01)
    buff << res if res
    timeo = etime - ::Time.now.to_f
  end

  buff
end

#shell_init ⇒ Object

:category: Msf::Session::Provider::SingleCommandShell implementors

The shell will have been initialized by default.


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# File 'lib/msf/base/sessions/command_shell.rb', line 82

def shell_init
  return true
end

#shell_read(length = -1,, timeout = 1) ⇒ Object

:category: Msf::Session::Provider::SingleCommandShell implementors

Read from the command shell.


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# File 'lib/msf/base/sessions/command_shell.rb', line 115

def shell_read(length=-1, timeout=1)
  return shell_read_ring(length,timeout) if self.respond_to?(:ring)

  begin
    rv = rstream.get_once(length, timeout)
    framework.events.on_session_output(self, rv) if rv
    return rv
  rescue ::Rex::SocketError, ::EOFError, ::IOError, ::Errno::EPIPE => e
    #print_error("Socket error: #{e.class}: #{e}")
    shell_close
    raise e
  end
end

#shell_read_ring(length = -1,, timeout = 1) ⇒ Object

Read from the command shell.


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# File 'lib/msf/base/sessions/command_shell.rb', line 132

def shell_read_ring(length=-1, timeout=1)
  self.ring_buff ||= ""

  # Short-circuit bad length values
  return "" if length == 0

  # Return data from the stored buffer if available
  if self.ring_buff.length >= length and length > 0
    buff = self.ring_buff.slice!(0,length)
    return buff
  end

  buff = self.ring_buff
  self.ring_buff = ""

  begin
    ::Timeout.timeout(timeout) do
      while( (length > 0 and buff.length < length) or (length == -1 and buff.length == 0))
        ring.select
        nseq,data = ring.read_data(self.ring_seq)
        if data
          self.ring_seq = nseq
          buff << data
        end
      end
    end
  rescue ::Timeout::Error
  rescue ::Rex::SocketError, ::EOFError, ::IOError, ::Errno::EPIPE => e
    shell_close
    raise e
  end

  # Store any leftovers in the ring buffer backlog
  if length > 0 and buff.length > length
    self.ring_buff = buff[length, buff.length - length]
    buff = buff[0,length]
  end

  buff
end

#shell_write(buf) ⇒ Object

:category: Msf::Session::Provider::SingleCommandShell implementors

Writes to the command shell.


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# File 'lib/msf/base/sessions/command_shell.rb', line 178

def shell_write(buf)
  return if not buf

  begin
    framework.events.on_session_command(self, buf.strip)
    rstream.write(buf)
  rescue ::Rex::SocketError, ::EOFError, ::IOError, ::Errno::EPIPE => e
    #print_error("Socket error: #{e.class}: #{e}")
    shell_close
    raise e
  end
end

#type ⇒ Object

Calls the class method.


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# File 'lib/msf/base/sessions/command_shell.rb', line 73

def type
  self.class.type
end