Class: Rex::Proto::Http::WebSocket::AmazonSsm::Interface::SsmChannel

Inherits:
Interface::Channel show all
Includes:
SsmChannelMethods
Defined in:
lib/rex/proto/http/web_socket/amazon_ssm.rb

Instance Attribute Summary collapse

Attributes included from SsmChannelMethods

#cols, #rows

Attributes inherited from Interface::Channel

#params

Instance Method Summary collapse

Methods included from SsmChannelMethods

#_start_ssm_keepalive, #acknowledge_output, #close, #handle_acknowledge, #handle_output_data, #pause_publication, #set_term_size, #start_publication, #update_term_size

Methods inherited from Interface::Channel

#close, #close_write, #closed?, #write

Methods included from Rex::Post::Channel::StreamAbstraction

#read

Constructor Details

#initialize(websocket) ⇒ SsmChannel

Returns a new instance of SsmChannel.



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# File 'lib/rex/proto/http/web_socket/amazon_ssm.rb', line 150

def initialize(websocket)
  @ack_seq_num = 0
  @out_seq_num = 0
  @run_ssm_pub = true
  @ack_message = nil
  @publication = false

  super(websocket, write_type: :binary)
end

Instance Attribute Details

#ack_message ⇒ Object (readonly)

Returns the value of attribute ack_message.



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# File 'lib/rex/proto/http/web_socket/amazon_ssm.rb', line 148

def ack_message
  @ack_message
end

#ack_seq_num ⇒ Object (readonly)

Returns the value of attribute ack_seq_num.



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# File 'lib/rex/proto/http/web_socket/amazon_ssm.rb', line 148

def ack_seq_num
  @ack_seq_num
end

#out_seq_num ⇒ Object (readonly)

Returns the value of attribute out_seq_num.



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# File 'lib/rex/proto/http/web_socket/amazon_ssm.rb', line 148

def out_seq_num
  @out_seq_num
end

#run_ssm_pub ⇒ Object (readonly)

Returns the value of attribute run_ssm_pub.



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# File 'lib/rex/proto/http/web_socket/amazon_ssm.rb', line 148

def run_ssm_pub
  @run_ssm_pub
end

Instance Method Details

#on_data_read(data, _data_type) ⇒ Object 



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# File 'lib/rex/proto/http/web_socket/amazon_ssm.rb', line 160

def on_data_read(data, _data_type)
  return data if data.blank?

  ssm_frame = SsmFrame.read(data)
  case ssm_frame.header.message_type.strip
  when 'output_stream_data'
    @publication = true # Linux sends stream data before sending start_publication message
    return handle_output_data(ssm_frame)
  when 'acknowledge'
    # update ACK seqno
    handle_acknowledge(ssm_frame)
  when 'start_publication'
    @out_seq_num = @ack_seq_num if @out_seq_num > 0
    @publication = true
    # handle session resumption - foregrounding or resumption of input
  when 'pause_publication'
    # @websocket.put_wsbinary(ssm_frame.to_ack.to_binary_s)
    @publication = false
    # handle session suspension - backgrounding or general idle
  when 'input_stream_data'
    # this is supposed to be a one way street
    emsg = "SsmChannel received input_stream_data from SSM (!!)"
    elog(emsg)
    raise emsg
  when 'channel_closed'
    elog("SsmChannel got closed message #{ssm_frame.uuid}")
    close
  else
    raise Rex::Proto::Http::WebSocket::ConnectionError.new(
      msg: "Unknown AWS SSM message type: #{ssm_frame.header.message_type}"
    )
  end

  nil
end

#on_data_write(data) ⇒ Object 



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# File 'lib/rex/proto/http/web_socket/amazon_ssm.rb', line 196

def on_data_write(data)
  start_publication if not @publication
  frame = SsmFrame.create(data)
  frame.header.sequence_number = @out_seq_num
  @out_seq_num += 1
  frame.to_binary_s
end

#publishing? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rex/proto/http/web_socket/amazon_ssm.rb', line 204

def publishing?
  @publication
end