Class: PSRP::MessageDecoder

Inherits:
Message
  • Object
show all
Defined in:
lib/wsmv/psrp_message.rb

Constant Summary

Constants inherited from Message

PSRP::Message::BLOB_HEADER_LEN, PSRP::Message::BLOB_MAX_LEN, PSRP::Message::MESSAGE_TYPES

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Message

#uuid_to_windows_guid_bytes

Constructor Details

#initialize(raw_text) ⇒ MessageDecoder

Returns a new instance of MessageDecoder.


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# File 'lib/wsmv/psrp_message.rb', line 92

def initialize(raw_text)
  # Message ID - 8bytes
  # Fragment ID - 8bytes
  # reserved - 6bits
  # end fragment - 1bit
  # start fragment - 1bit
  # blob_length - 4bytes
  # destination - 4bytes
  # message_type - 4bytes
  # client runspace GUID - 16bytes
  # client PID GUID - 16bytes
  # BOM 3bytes
  # 
  # Data - blob_length - 43 bytes (40 blob bytes + BOM)
  unencoded = Base64.decode64(raw_text)
  fields = unencoded.unpack('Q>2CL>L<2h32h32C3A*')

  @message_id = fields[0]
  @fragment_id = fields[1]
  @fragment_flags = fields[2]
  @blob_length = fields[3]
  
  if is_start_fragment?
    @destination = fields[4]
    @message_type = fields[5]
    @client_runspace = fields[6]
    @client_pid = fields[7]
    @data = fields[11]
  else
    fields = unencoded.unpack('Q>2CL>A*')
    @destination = nil
    @message_type = nil
    @client_runspace = nil
    @client_pid = nil
    @data = fields[4]
  end
end

Instance Attribute Details

#blob_length ⇒ Object (readonly)

Returns the value of attribute blob_length.


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# File 'lib/wsmv/psrp_message.rb', line 90

def blob_length
  @blob_length
end

#client_pid ⇒ Object (readonly)

Returns the value of attribute client_pid.


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# File 'lib/wsmv/psrp_message.rb', line 90

def client_pid
  @client_pid
end

#client_runspace ⇒ Object (readonly)

Returns the value of attribute client_runspace.


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# File 'lib/wsmv/psrp_message.rb', line 90

def client_runspace
  @client_runspace
end

#data ⇒ Object (readonly)

Returns the value of attribute data.


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# File 'lib/wsmv/psrp_message.rb', line 90

def data
  @data
end

#destination ⇒ Object (readonly)

Returns the value of attribute destination.


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# File 'lib/wsmv/psrp_message.rb', line 90

def destination
  @destination
end

#fragment_flags ⇒ Object (readonly)

Returns the value of attribute fragment_flags.


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# File 'lib/wsmv/psrp_message.rb', line 90

def fragment_flags
  @fragment_flags
end

#fragment_id ⇒ Object (readonly)

Returns the value of attribute fragment_id.


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# File 'lib/wsmv/psrp_message.rb', line 90

def fragment_id
  @fragment_id
end

#message_id ⇒ Object (readonly)

Returns the value of attribute message_id.


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# File 'lib/wsmv/psrp_message.rb', line 90

def message_id
  @message_id
end

#message_type ⇒ Object (readonly)

Returns the value of attribute message_type.


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# File 'lib/wsmv/psrp_message.rb', line 90

def message_type
  @message_type
end

Instance Method Details

#is_end_fragment? ⇒ Boolean

Returns:

  • (Boolean) 

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# File 'lib/wsmv/psrp_message.rb', line 130

def is_end_fragment?
  (@fragment_flags & 2) != 0
end

#is_start_fragment? ⇒ Boolean

Returns:

  • (Boolean) 

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# File 'lib/wsmv/psrp_message.rb', line 134

def is_start_fragment?
  (@fragment_flags & 1) != 0
end