Class: Msf::Sessions::SshCommandShellBind
- Inherits:
-
CommandShell
- Object
- CommandShell
- Msf::Sessions::SshCommandShellBind
- Includes:
- Msf::Session::Comm, Rex::Post::Channel::Container
- Defined in:
- lib/msf/base/sessions/ssh_command_shell_bind.rb
Overview
This class provides a session for SSH client connections, where Metasploit has authenticated to a remote SSH server. It is compatible with the Net::SSH library.
Defined Under Namespace
Modules: ChannelFailureReason Classes: TcpClientChannel, TcpServerChannel
Instance Attribute Summary collapse
-
#sock ⇒ Object
readonly
Returns the value of attribute sock.
-
#ssh_connection ⇒ Object
readonly
Returns the value of attribute ssh_connection.
Attributes included from Rex::Post::Channel::Container
Attributes inherited from CommandShell
#arch, #banner, #max_threads, #platform
Attributes included from Msf::Session::Interactive
Attributes included from Rex::Ui::Interactive
#completed, #interacting, #next_session, #on_command_proc, #on_print_proc, #on_run_command_error_proc, #orig_suspend, #orig_usr1, #orig_winch
Attributes included from Rex::Ui::Subscriber::Input
Attributes included from Rex::Ui::Subscriber::Output
Attributes included from Msf::Session
#alive, #db_record, #exploit, #exploit_datastore, #exploit_task, #exploit_uuid, #framework, #info, #machine_id, #payload_uuid, #routes, #sid, #sname, #target_host, #target_port, #username, #uuid, #via, #workspace
Attributes included from Framework::Offspring
Instance Method Summary collapse
- #bootstrap(datastore = {}, handler = nil) ⇒ Object
- #cleanup ⇒ Object
-
#create(params) ⇒ TcpClientChannel
Create a network socket using this session.
- #create_client_channel(params) ⇒ Object
- #create_server_channel(params) ⇒ Object
- #desc ⇒ Object
-
#initialize(ssh_connection, opts = {}) ⇒ SshCommandShellBind
constructor
Create a sessions instance from an SshConnection.
-
#on_got_remote_connection(_session, channel, packet) ⇒ Object
The SSH server has told us that there’s a port forwarding request.
- #stop_server_channel(host, port) ⇒ Object
- #supports_udp? ⇒ Boolean
Methods included from Rex::Post::Channel::Container
#add_channel, #find_channel, #initialize_channels, #remove_channel
Methods inherited from CommandShell
#_file_transfer, _glue_cmdline_escape, #_interact, #_interact_stream, #abort_foreground_supported, binary_exists, #binary_exists, can_cleanup_files, #cmd_background, #cmd_background_help, #cmd_download, #cmd_download_help, #cmd_help, #cmd_help_help, #cmd_irb, #cmd_irb_help, #cmd_pry, #cmd_pry_help, #cmd_resource, #cmd_resource_help, #cmd_sessions, #cmd_sessions_help, #cmd_shell, #cmd_shell_help, #cmd_source, #cmd_source_help, #cmd_upload, #cmd_upload_help, #commands, #docs_dir, #execute_file, #process_autoruns, #run_builtin_cmd, #run_single, #shell_close, #shell_command, #shell_init, #shell_read, #shell_write, type, #type
Methods included from Rex::Ui::Text::Resource
Methods included from Scriptable
#execute_file, #execute_script, included, #legacy_script_to_post_module
Methods included from Msf::Session::Provider::SingleCommandShell
#command_termination, #set_is_echo_shell, #shell_close, #shell_command_token, #shell_command_token_base, #shell_command_token_unix, #shell_command_token_win32, #shell_init, #shell_read, #shell_read_until_token, #shell_write, #to_cmd
Methods included from Msf::Session::Basic
Methods included from Msf::Session::Interactive
#_interact, #_interact_complete, #_interrupt, #_suspend, #_usr1, #abort_foreground, #abort_foreground_supported, #comm_channel, #interactive?, #kill, #run_cmd, #tunnel_local, #tunnel_peer, #user_want_abort?
Methods included from Rex::Ui::Interactive
#_interact, #_interact_complete, #_interrupt, #_local_fd, #_remote_fd, #_stream_read_local_write_remote, #_stream_read_remote_write_local, #_suspend, #_winch, #detach, #handle_suspend, #handle_usr1, #handle_winch, #interact, #interact_stream, #prompt, #prompt_yesno, #restore_suspend, #restore_usr1, #restore_winch
Methods included from Rex::Ui::Subscriber
Methods included from Rex::Ui::Subscriber::Input
Methods included from Rex::Ui::Subscriber::Output
#flush, #print, #print_blank_line, #print_error, #print_good, #print_line, #print_status, #print_warning
Methods included from Msf::Session
#alive?, #comm_channel, #dead?, #inspect, #interactive?, #kill, #log_file_name, #log_source, #name, #name=, #register?, #session_host, #session_host=, #session_port, #session_port=, #session_type, #set_from_exploit, #set_via, #tunnel_local, #tunnel_peer, #tunnel_to_s, type, #type, #via_exploit, #via_payload
Constructor Details
#initialize(ssh_connection, opts = {}) ⇒ SshCommandShellBind
Create a sessions instance from an SshConnection. This will handle creating a new command stream.
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 225 def initialize(ssh_connection, opts = {}) @ssh_connection = ssh_connection @sock = ssh_connection.transport.socket @server_channels = {} initialize_channels @channel_ticker = 0 # Be alerted to reverse port forward connections (once we start listening on a port) ssh_connection.on_open_channel('forwarded-tcpip', &method(:on_got_remote_connection)) super(nil, opts) end |
Instance Attribute Details
#sock ⇒ Object (readonly)
Returns the value of attribute sock.
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 427 def sock @sock end |
#ssh_connection ⇒ Object (readonly)
Returns the value of attribute ssh_connection.
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 427 def ssh_connection @ssh_connection end |
Instance Method Details
#bootstrap(datastore = {}, handler = nil) ⇒ Object
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 238 def bootstrap(datastore = {}, handler = nil) # this won't work after the rstream is initialized, so do it first @platform = Metasploit::Framework::Ssh::Platform.get_platform(ssh_connection) # if the platform is known, it was recovered by communicating with the device, so skip verification, also not all # shells accessed through SSH may respond to the echo command issued for verification as expected datastore['AutoVerifySession'] &= @platform.blank? @rstream = Net::SSH::CommandStream.new(ssh_connection, session: self, logger: self).lsock super @info = "SSH #{username} @ #{@peer_info}" end |
#cleanup ⇒ Object
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 420 def cleanup channels.each_value(&:close) @server_channels.each_value(&:close) super end |
#create(params) ⇒ TcpClientChannel
Create a network socket using this session. At this time, only TCP client connections can be made (like SSH port forwarding) while TCP server sockets can not be opened (SSH reverse port forwarding). The SSH specification does not define a UDP channel, so that is not supported either.
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 268 def create(params) # Notify handlers before we create the socket notify_before_socket_create(self, params) if params.proto == 'tcp' if params.server sock = create_server_channel(params) else sock = create_client_channel(params) end elsif params.proto == 'udp' raise ::Rex::ConnectionError.new(params.peerhost, params.peerport, reason: 'UDP sockets are not supported by SSH sessions.') end raise ::Rex::ConnectionError unless sock # Notify now that we've created the socket notify_socket_created(self, sock, params) sock end |
#create_client_channel(params) ⇒ Object
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 354 def create_client_channel(params) msf_channel = nil mutex = Mutex.new condition = ConditionVariable.new opened = false ssh_channel = @ssh_connection.open_channel('direct-tcpip', :string, params.peerhost, :long, params.peerport, :string, params.localhost, :long, params.localport) do |_| dlog("new direct-tcpip channel opened to #{Rex::Socket.is_ipv6?(params.peerhost) ? '[' + params.peerhost + ']' : params.peerhost}:#{params.peerport}") opened = true mutex.synchronize do condition.signal end end failure_reason_code = nil ssh_channel.on_open_failed do |_ch, code, desc| failure_reason_code = code wlog("failed to open SSH channel (code: #{code.inspect}, description: #{desc.inspect})") mutex.synchronize do condition.signal end end mutex.synchronize do timeout = params.timeout.to_i <= 0 ? nil : params.timeout condition.wait(mutex, timeout) end unless opened ssh_channel.close raise ::Rex::ConnectionTimeout.new(params.peerhost, params.peerport) if failure_reason_code.nil? case failure_reason_code when ChannelFailureReason::SSH_OPEN_ADMINISTRATIVELY_PROHIBITED reason = 'The SSH channel request was administratively prohibited.' when ChannelFailureReason::SSH_OPEN_UNKNOWN_CHANNEL_TYPE reason = 'The SSH channel type is not supported.' when ChannelFailureReason::SSH_OPEN_RESOURCE_SHORTAGE reason = 'The SSH channel request was denied because of a resource shortage.' end raise ::Rex::ConnectionError.new(params.peerhost, params.peerport, reason: reason) end msf_channel = TcpClientChannel.new(self, @channel_ticker += 1, ssh_channel, params) sock = msf_channel.lsock # Notify now that we've created the socket notify_socket_created(self, sock, params) sock end |
#create_server_channel(params) ⇒ Object
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 294 def create_server_channel(params) msf_channel = nil mutex = Mutex.new condition = ConditionVariable.new timed_out = false @ssh_connection.send_global_request('tcpip-forward', :string, params.localhost, :long, params.localport) do |success, response| mutex.synchronize { remote_port = params.localport remote_port = response.read_long if remote_port == 0 if success if timed_out # We're not using the port; clean it up elog("Remote forwarding on #{params.localhost}:#{params.localport} succeeded after timeout. Stopping channel to clean up dangling port") stop_server_channel(params.localhost, remote_port) else dlog("Remote forwarding from #{params.localhost} established on port #{remote_port}") key = [params.localhost, remote_port] msf_channel = TcpServerChannel.new(params, self, params.localhost, remote_port) @server_channels[key] = msf_channel end else elog("Remote forwarding failed on #{params.localhost}:#{params.localport}") end condition.signal } end mutex.synchronize { condition.wait(mutex, params.timeout) unless msf_channel timed_out = true end } # Return the server channel itself msf_channel end |
#desc ⇒ Object
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 252 def desc "SSH" end |
#on_got_remote_connection(_session, channel, packet) ⇒ Object
The SSH server has told us that there’s a port forwarding request. Find the relevant server channel and inform it.
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 407 def on_got_remote_connection(_session, channel, packet) connected_address = packet.read_string connected_port = packet.read_long originator_address = packet.read_string originator_port = packet.read_long ilog("Received connection: #{connected_address}:#{connected_port} <--> #{originator_address}:#{originator_port}") # Find the correct TcpServerChannel # key = [connected_address, connected_port] server_channel = @server_channels[key] server_channel.create(@channel_ticker += 1, channel, originator_address, originator_port) end |
#stop_server_channel(host, port) ⇒ Object
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 332 def stop_server_channel(host, port) completed_event = Rex::Sync::Event.new dlog("Cancelling tcpip-forward to #{host}:#{port}") @ssh_connection.send_global_request('cancel-tcpip-forward', :string, host, :long, port) do |success, _response| if success key = [host, port] @server_channels.delete(key) ilog("Reverse SSH listener on #{host}:#{port} stopped") else elog("Could not stop reverse listener on #{host}:#{port}") end completed_event.set end timeout = 5 # seconds begin completed_event.wait(timeout) true rescue ::Timeout::Error false end end |
#supports_udp? ⇒ Boolean
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# File 'lib/msf/base/sessions/ssh_command_shell_bind.rb', line 290 def supports_udp? false end |