RedVTY

class redvty.RedVTY(*args, columns=80, rows=24, **kwargs)

Bases: redexpect.redexpect.RedExpect

close_tunnels()

Closes all SSH tunnels if any are open.

command(cmd, clean_output=True, remove_newline=False, timeout=None)

Run a command in the remote terminal.

Parameters

• cmd (str) – Command to execute, this will send characters exactly as if they were typed. (crtl+c could be sent via this).

• clean_output (bool) – Set to False to remove the “smart” cleaning, useful for debugging or for when you want the prompt as well.

• remove_newline (bool) – Set to True to remove the last newline on a return, useful when a command adds a newline to its output.

• timeout (float) – Set the timeout for this command to complete within, if set to None this will use the value of :var:`redexpect.RedExpect.expect_timeout` which can be set at first instance.

Returns

str

Raises

redexpect.exceptions.ExpectTimeout if the timeout for expect has been reached.

connect(hostname, port=22, username=None, password=None, allow_agent=False, key_filepath=None, passphrase=None, look_for_keys=True, sock=None, timeout=None)

Warning

Some authentication methods are not yet supported!

Parameters

• hostname (str) – Hostname to connect to.

• port (int) – SSH port to connect to.

• username (str) – Username to connect as to the remote server.

• password (str) – Password to offer to the remote server for authentication.

• allow_agent (bool) – Allow the local SSH key agent to offer the keys held in it for authentication.

• key_filepath (array/str) – Array of filenames to offer to the remote server. Can be a string for a single key.

• passphrase (str) – Passphrase to decrypt any keys offered to the remote server.

• look_for_keys (bool) – Enable offering keys in ~/.ssh automatically. NOT IMPLEMENTED!

• sock (socket) – A pre-connected socket to the remote server. Useful if you have strange network requirements.

• timeout (float) – Timeout for the socket connection to the remote server.

device_init(**kwargs)

Override this function to intialize a device that does not simply drop to the terminal or a device will kick you out if you send any key/character other than an “acceptable” one. This default one will work on linux quite well but devices such as pfsense or mikrotik might require this function and redexpect.RedExpect.get_unique_prompt() to be overriden.

dynamic_tunnel(local_port, bind_addr='127.0.0.1', error_level=<TunnelErrorLevel.warn: 1>)

Opens a SOCKS proxy AKA gateway or dynamic port the same way the -D option does for the OpenSSH client.

Providing a 0 for the local port will mean the OS will assign an unbound port for you. This port number will be provided to you by this function.

Parameters

• local_port (int) – The local port on the local machine to bind to.

• bind_addr (str) – The bind address on this machine to bind to for the local port.

• error_level (redssh.enums.TunnelErrorLevel) – The level of verbosity that errors in tunnel threads will use.

Returns

int The local port that has been bound.

eof()

Returns True or False when the main channel has recieved an EOF.

exit()

Kill the current session if connected.

expect(re_strings='', default_match_prefix='', strip_ansi=True, timeout=None)

This function takes in a regular expression (or regular expressions) that represent the last line of output from the server. The function waits for one or more of the terms to be matched. The regexes are matched using expression r'\n<regex>$' so you’ll need to provide an easygoing regex such as '.*server.*' if you wish to have a fuzzy match.

This has been originally taken from paramiko_expect and modified to work with RedExpect. I’ve also made the style consistent with the rest of the library.

Parameters

• re_strings (array or regex str) – Either a regex string or list of regex strings that we should expect; if this is not specified, then EOF is expected (i.e. the shell is completely closed after the exit command is issued)

• default_match_prefix (str) – A prefix to all match regexes, defaults to ''. Useful for making sure you have a prefix to match the start of a prompt.

• strip_ansi (bool) – If True, will strip ansi control chars befores regex matching.

• timeout (float) – Set the timeout for this finish blocking within, setting to None takes the value from :var:`redexpect.RedExpect.expect_timeout` which can be set at first instance, set to 0 to disable.

Returns

int - An EOF returns -1, a regex metch returns 0 and a match in a list of regexes returns the index of the matched string in the list.

Raises

redexpect.exceptions.ExpectTimeout if the timeout for expect has been reached.

get_unique_prompt()

Return a unique prompt from the existing SSH session. Override this function to generate the compiled regex however you’d like, eg, from a database or from a hostname.

Returns

compiled regex str

last_error()

Get the last error from the current session.

Returns

str

local_tunnel(local_port, remote_host, remote_port, bind_addr='127.0.0.1', error_level=<TunnelErrorLevel.warn: 1>)

Forwards a port on the remote machine the same way the -L option does for the OpenSSH client.

Providing a 0 for the local port will mean the OS will assign an unbound port for you. This port number will be provided to you by this function.

Parameters

• local_port (int) – The local port on the local machine to bind to.

• remote_host (str) – The remote host to connect to via the remote machine.

• remote_port (int) – The remote host’s port to connect to via the remote machine.

• bind_addr (str) – The bind address on this machine to bind to for the local port.

• error_level (redssh.enums.TunnelErrorLevel) – The level of verbosity that errors in tunnel threads will use.

Returns

int The local port that has been bound.

login(*args, auto_unique_prompt=True, **kwargs)

This uses redssh.RedSSH.connect to connect and then login to a remote host. This only takes a single optional arguement and the rest are defered to redssh.RedSSH.connect.

Parameters

auto_unique_prompt (float) – Automatically set a unique prompt to search for once logged into the remote server.

methods(method)

Returns what value was settled on during session negotiation.

out_feed(data)

Override to get the raw data from the remote machine into a function.

Useful as a way to get data from the expect() to another library without impacting the expect side.

prompt(additional_matches=[], timeout=None)

Get a command line prompt in the terminal. Useful for using redexpect.RedExpect.sendline() to send commands then using this for when you want to get back to a prompt to enter further commands.

Parameters

• additional_matches (arr) – Additional matches to count as a prompt.

• timeout (float or int) – Timeout for the prompt to be reached.

Raises

redexpect.exceptions.ExpectTimeout if the timeout for expect has been reached.

Returns

int - Match number, 0 is always the prompt defined for the session.

read(block=False)

Recieve data from the remote session. Only works if the current session has made it past the login process.

Parameters

block – Block until data is received from the remote server. True

will block until data is recieved and False may return b'' if no data is available from the remote server. :type block: bool :return: generator - A generator of byte strings that has been recieved in the time given.

remote_tunnel(local_port, remote_host, remote_port, bind_addr='127.0.0.1', error_level=<TunnelErrorLevel.warn: 1>)

Forwards a port to the remote machine via the local machine the same way the -R option does for the OpenSSH client.

Parameters

• local_port (int) – The local port on the remote side to connect to.

• remote_host (str) – The remote host to connect to via the local machine.

• remote_port (int) – The remote host’s port to connect to via the local machine.

• error_level (redssh.enums.TunnelErrorLevel) – The level of verbosity that errors in tunnel threads will use.

Returns

None

send(string)

Send data to the remote session. Only works if the current session has made it past the login process.

Parameters

string (str) – String to send to the remote session.

Returns

int - Amount of bytes sent to remote machine.

sendline(send_string, newline=None)

Saves and sends the send string provided to the remote session with a newline added.

Parameters

• send_string (str) – String to send to the remote session.

• newline (str) – Override the newline character sent to the remote session.

sendline_raw(string)

Use this when you want to directly interact with the remote session.

Parameters

string (str) – String to send to the remote session.

set_unique_prompt(use_basic_prompt=True, set_prompt=False)

Set a unique prompt in the existing SSH session.

Parameters

• use_basic_prompt (bool) – Use the dumb prompt from first login to the remote terminal.

• set_prompt (bool) – Set to True to set the prompt via :var:`redexpect.RedExpect.PROMPT_SET_SH`

setenv(varname, value)

Set an environment variable on the channel.

Parameters

• varname (str) – Name of environment variable to set on the remote channel.

• value (str) – Value to set varname to.

Returns

None

shutdown_tunnel(tunnel_type, sport, rhost=None, rport=None, bind_addr='127.0.0.1')

Closes an open tunnel. Provide the same arguments to this that was given for openning the tunnel.

Examples:

local_tunnel(9999,’localhost’,8888) would be shutdown_tunnel(redssh.enums.TunnelType.local,9999,’localhost’,8888)

remote_tunnel(7777,’localhost’,8888) would be shutdown_tunnel(redssh.enums.TunnelType.remote,7777,’localhost’,8888)

dynamic_tunnel(9999) would be shutdown_tunnel(redssh.enums.TunnelType.dynamic,9999)

dynamic_tunnel(9999,’10.0.0.1’) would be shutdown_tunnel(redssh.enums.TunnelType.dynamic,9999,bind_addr=’10.0.0.1’)

Parameters

• tunnel_type (redssh.enums.TunnelType) – The tunnel type to shutdown.

• sport (str) – The bound port for local and dynamic tunnels or the local port on the remote side for remote tunnels.

• rhost (str) – The remote host for local and remote tunnels.

• rport (int) – The remote port for local and remote tunnels.

• bind_addr (str) – The bind address used for local and dynamic tunnels.

Returns

None

start_scp()

Start the SCP client.

Returns

None

start_sftp()

Start the SFTP client.

Returns

None

sudo(password, sudo=True, su_cmd='su -')

Sudo up or SU up or whatever up, into higher privileges.

Parameters

• password (str) – Password for gaining privileges

• sudo (bool) – Set to False to allow su_cmd to be executed instead.

• su_cmd (str) – Command to be executed when sudo is False, allows overriding of the 'sudo' default.

Returns

None

Raises

redexpect.exceptions.BadSudoPassword if the password provided does not allow for privilege escalation.

supported_algs(method, algs)

Returns what values are available for session negotiation.