678 lines
23 KiB
Python
678 lines
23 KiB
Python
|
r"""TELNET client class.
|
||
|
|
|
||
|
|
Based on RFC 854: TELNET Protocol Specification, by J. Postel and
|
||
|
|
J. Reynolds
|
||
|
|
|
||
|
|
Example:
|
||
|
|
|
||
|
|
>>> from telnetlib import Telnet
|
||
|
|
>>> tn = Telnet('www.python.org', 79) # connect to finger port
|
||
|
|
>>> tn.write(b'guido\r\n')
|
||
|
|
>>> print(tn.read_all())
|
||
|
|
Login Name TTY Idle When Where
|
||
|
|
guido Guido van Rossum pts/2 <Dec 2 11:10> snag.cnri.reston..
|
||
|
|
|
||
|
|
>>>
|
||
|
|
|
||
|
|
Note that read_all() won't read until eof -- it just reads some data
|
||
|
|
-- but it guarantees to read at least one byte unless EOF is hit.
|
||
|
|
|
||
|
|
It is possible to pass a Telnet object to a selector in order to wait until
|
||
|
|
more data is available. Note that in this case, read_eager() may return b''
|
||
|
|
even if there was data on the socket, because the protocol negotiation may have
|
||
|
|
eaten the data. This is why EOFError is needed in some cases to distinguish
|
||
|
|
between "no data" and "connection closed" (since the socket also appears ready
|
||
|
|
for reading when it is closed).
|
||
|
|
|
||
|
|
To do:
|
||
|
|
- option negotiation
|
||
|
|
- timeout should be intrinsic to the connection object instead of an
|
||
|
|
option on one of the read calls only
|
||
|
|
|
||
|
|
"""
|
||
|
|
|
||
|
|
|
||
|
|
# Imported modules
|
||
|
|
import sys
|
||
|
|
import socket
|
||
|
|
import selectors
|
||
|
|
from time import monotonic as _time
|
||
|
|
|
||
|
|
__all__ = ["Telnet"]
|
||
|
|
|
||
|
|
# Tunable parameters
|
||
|
|
DEBUGLEVEL = 0
|
||
|
|
|
||
|
|
# Telnet protocol defaults
|
||
|
|
TELNET_PORT = 23
|
||
|
|
|
||
|
|
# Telnet protocol characters (don't change)
|
||
|
|
IAC = bytes([255]) # "Interpret As Command"
|
||
|
|
DONT = bytes([254])
|
||
|
|
DO = bytes([253])
|
||
|
|
WONT = bytes([252])
|
||
|
|
WILL = bytes([251])
|
||
|
|
theNULL = bytes([0])
|
||
|
|
|
||
|
|
SE = bytes([240]) # Subnegotiation End
|
||
|
|
NOP = bytes([241]) # No Operation
|
||
|
|
DM = bytes([242]) # Data Mark
|
||
|
|
BRK = bytes([243]) # Break
|
||
|
|
IP = bytes([244]) # Interrupt process
|
||
|
|
AO = bytes([245]) # Abort output
|
||
|
|
AYT = bytes([246]) # Are You There
|
||
|
|
EC = bytes([247]) # Erase Character
|
||
|
|
EL = bytes([248]) # Erase Line
|
||
|
|
GA = bytes([249]) # Go Ahead
|
||
|
|
SB = bytes([250]) # Subnegotiation Begin
|
||
|
|
|
||
|
|
|
||
|
|
# Telnet protocol options code (don't change)
|
||
|
|
# These ones all come from arpa/telnet.h
|
||
|
|
BINARY = bytes([0]) # 8-bit data path
|
||
|
|
ECHO = bytes([1]) # echo
|
||
|
|
RCP = bytes([2]) # prepare to reconnect
|
||
|
|
SGA = bytes([3]) # suppress go ahead
|
||
|
|
NAMS = bytes([4]) # approximate message size
|
||
|
|
STATUS = bytes([5]) # give status
|
||
|
|
TM = bytes([6]) # timing mark
|
||
|
|
RCTE = bytes([7]) # remote controlled transmission and echo
|
||
|
|
NAOL = bytes([8]) # negotiate about output line width
|
||
|
|
NAOP = bytes([9]) # negotiate about output page size
|
||
|
|
NAOCRD = bytes([10]) # negotiate about CR disposition
|
||
|
|
NAOHTS = bytes([11]) # negotiate about horizontal tabstops
|
||
|
|
NAOHTD = bytes([12]) # negotiate about horizontal tab disposition
|
||
|
|
NAOFFD = bytes([13]) # negotiate about formfeed disposition
|
||
|
|
NAOVTS = bytes([14]) # negotiate about vertical tab stops
|
||
|
|
NAOVTD = bytes([15]) # negotiate about vertical tab disposition
|
||
|
|
NAOLFD = bytes([16]) # negotiate about output LF disposition
|
||
|
|
XASCII = bytes([17]) # extended ascii character set
|
||
|
|
LOGOUT = bytes([18]) # force logout
|
||
|
|
BM = bytes([19]) # byte macro
|
||
|
|
DET = bytes([20]) # data entry terminal
|
||
|
|
SUPDUP = bytes([21]) # supdup protocol
|
||
|
|
SUPDUPOUTPUT = bytes([22]) # supdup output
|
||
|
|
SNDLOC = bytes([23]) # send location
|
||
|
|
TTYPE = bytes([24]) # terminal type
|
||
|
|
EOR = bytes([25]) # end or record
|
||
|
|
TUID = bytes([26]) # TACACS user identification
|
||
|
|
OUTMRK = bytes([27]) # output marking
|
||
|
|
TTYLOC = bytes([28]) # terminal location number
|
||
|
|
VT3270REGIME = bytes([29]) # 3270 regime
|
||
|
|
X3PAD = bytes([30]) # X.3 PAD
|
||
|
|
NAWS = bytes([31]) # window size
|
||
|
|
TSPEED = bytes([32]) # terminal speed
|
||
|
|
LFLOW = bytes([33]) # remote flow control
|
||
|
|
LINEMODE = bytes([34]) # Linemode option
|
||
|
|
XDISPLOC = bytes([35]) # X Display Location
|
||
|
|
OLD_ENVIRON = bytes([36]) # Old - Environment variables
|
||
|
|
AUTHENTICATION = bytes([37]) # Authenticate
|
||
|
|
ENCRYPT = bytes([38]) # Encryption option
|
||
|
|
NEW_ENVIRON = bytes([39]) # New - Environment variables
|
||
|
|
# the following ones come from
|
||
|
|
# http://www.iana.org/assignments/telnet-options
|
||
|
|
# Unfortunately, that document does not assign identifiers
|
||
|
|
# to all of them, so we are making them up
|
||
|
|
TN3270E = bytes([40]) # TN3270E
|
||
|
|
XAUTH = bytes([41]) # XAUTH
|
||
|
|
CHARSET = bytes([42]) # CHARSET
|
||
|
|
RSP = bytes([43]) # Telnet Remote Serial Port
|
||
|
|
COM_PORT_OPTION = bytes([44]) # Com Port Control Option
|
||
|
|
SUPPRESS_LOCAL_ECHO = bytes([45]) # Telnet Suppress Local Echo
|
||
|
|
TLS = bytes([46]) # Telnet Start TLS
|
||
|
|
KERMIT = bytes([47]) # KERMIT
|
||
|
|
SEND_URL = bytes([48]) # SEND-URL
|
||
|
|
FORWARD_X = bytes([49]) # FORWARD_X
|
||
|
|
PRAGMA_LOGON = bytes([138]) # TELOPT PRAGMA LOGON
|
||
|
|
SSPI_LOGON = bytes([139]) # TELOPT SSPI LOGON
|
||
|
|
PRAGMA_HEARTBEAT = bytes([140]) # TELOPT PRAGMA HEARTBEAT
|
||
|
|
EXOPL = bytes([255]) # Extended-Options-List
|
||
|
|
NOOPT = bytes([0])
|
||
|
|
|
||
|
|
|
||
|
|
# poll/select have the advantage of not requiring any extra file descriptor,
|
||
|
|
# contrarily to epoll/kqueue (also, they require a single syscall).
|
||
|
|
if hasattr(selectors, 'PollSelector'):
|
||
|
|
_TelnetSelector = selectors.PollSelector
|
||
|
|
else:
|
||
|
|
_TelnetSelector = selectors.SelectSelector
|
||
|
|
|
||
|
|
|
||
|
|
class Telnet:
|
||
|
|
|
||
|
|
"""Telnet interface class.
|
||
|
|
|
||
|
|
An instance of this class represents a connection to a telnet
|
||
|
|
server. The instance is initially not connected; the open()
|
||
|
|
method must be used to establish a connection. Alternatively, the
|
||
|
|
host name and optional port number can be passed to the
|
||
|
|
constructor, too.
|
||
|
|
|
||
|
|
Don't try to reopen an already connected instance.
|
||
|
|
|
||
|
|
This class has many read_*() methods. Note that some of them
|
||
|
|
raise EOFError when the end of the connection is read, because
|
||
|
|
they can return an empty string for other reasons. See the
|
||
|
|
individual doc strings.
|
||
|
|
|
||
|
|
read_until(expected, [timeout])
|
||
|
|
Read until the expected string has been seen, or a timeout is
|
||
|
|
hit (default is no timeout); may block.
|
||
|
|
|
||
|
|
read_all()
|
||
|
|
Read all data until EOF; may block.
|
||
|
|
|
||
|
|
read_some()
|
||
|
|
Read at least one byte or EOF; may block.
|
||
|
|
|
||
|
|
read_very_eager()
|
||
|
|
Read all data available already queued or on the socket,
|
||
|
|
without blocking.
|
||
|
|
|
||
|
|
read_eager()
|
||
|
|
Read either data already queued or some data available on the
|
||
|
|
socket, without blocking.
|
||
|
|
|
||
|
|
read_lazy()
|
||
|
|
Read all data in the raw queue (processing it first), without
|
||
|
|
doing any socket I/O.
|
||
|
|
|
||
|
|
read_very_lazy()
|
||
|
|
Reads all data in the cooked queue, without doing any socket
|
||
|
|
I/O.
|
||
|
|
|
||
|
|
read_sb_data()
|
||
|
|
Reads available data between SB ... SE sequence. Don't block.
|
||
|
|
|
||
|
|
set_option_negotiation_callback(callback)
|
||
|
|
Each time a telnet option is read on the input flow, this callback
|
||
|
|
(if set) is called with the following parameters :
|
||
|
|
callback(telnet socket, command, option)
|
||
|
|
option will be chr(0) when there is no option.
|
||
|
|
No other action is done afterwards by telnetlib.
|
||
|
|
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self, host=None, port=0,
|
||
|
|
timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
|
||
|
|
"""Constructor.
|
||
|
|
|
||
|
|
When called without arguments, create an unconnected instance.
|
||
|
|
With a hostname argument, it connects the instance; port number
|
||
|
|
and timeout are optional.
|
||
|
|
"""
|
||
|
|
self.debuglevel = DEBUGLEVEL
|
||
|
|
self.host = host
|
||
|
|
self.port = port
|
||
|
|
self.timeout = timeout
|
||
|
|
self.sock = None
|
||
|
|
self.rawq = b''
|
||
|
|
self.irawq = 0
|
||
|
|
self.cookedq = b''
|
||
|
|
self.eof = 0
|
||
|
|
self.iacseq = b'' # Buffer for IAC sequence.
|
||
|
|
self.sb = 0 # flag for SB and SE sequence.
|
||
|
|
self.sbdataq = b''
|
||
|
|
self.option_callback = None
|
||
|
|
if host is not None:
|
||
|
|
self.open(host, port, timeout)
|
||
|
|
|
||
|
|
def open(self, host, port=0, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
|
||
|
|
"""Connect to a host.
|
||
|
|
|
||
|
|
The optional second argument is the port number, which
|
||
|
|
defaults to the standard telnet port (23).
|
||
|
|
|
||
|
|
Don't try to reopen an already connected instance.
|
||
|
|
"""
|
||
|
|
self.eof = 0
|
||
|
|
if not port:
|
||
|
|
port = TELNET_PORT
|
||
|
|
self.host = host
|
||
|
|
self.port = port
|
||
|
|
self.timeout = timeout
|
||
|
|
sys.audit("telnetlib.Telnet.open", self, host, port)
|
||
|
|
self.sock = socket.create_connection((host, port), timeout)
|
||
|
|
|
||
|
|
def __del__(self):
|
||
|
|
"""Destructor -- close the connection."""
|
||
|
|
self.close()
|
||
|
|
|
||
|
|
def msg(self, msg, *args):
|
||
|
|
"""Print a debug message, when the debug level is > 0.
|
||
|
|
|
||
|
|
If extra arguments are present, they are substituted in the
|
||
|
|
message using the standard string formatting operator.
|
||
|
|
|
||
|
|
"""
|
||
|
|
if self.debuglevel > 0:
|
||
|
|
print('Telnet(%s,%s):' % (self.host, self.port), end=' ')
|
||
|
|
if args:
|
||
|
|
print(msg % args)
|
||
|
|
else:
|
||
|
|
print(msg)
|
||
|
|
|
||
|
|
def set_debuglevel(self, debuglevel):
|
||
|
|
"""Set the debug level.
|
||
|
|
|
||
|
|
The higher it is, the more debug output you get (on sys.stdout).
|
||
|
|
|
||
|
|
"""
|
||
|
|
self.debuglevel = debuglevel
|
||
|
|
|
||
|
|
def close(self):
|
||
|
|
"""Close the connection."""
|
||
|
|
sock = self.sock
|
||
|
|
self.sock = None
|
||
|
|
self.eof = True
|
||
|
|
self.iacseq = b''
|
||
|
|
self.sb = 0
|
||
|
|
if sock:
|
||
|
|
sock.close()
|
||
|
|
|
||
|
|
def get_socket(self):
|
||
|
|
"""Return the socket object used internally."""
|
||
|
|
return self.sock
|
||
|
|
|
||
|
|
def fileno(self):
|
||
|
|
"""Return the fileno() of the socket object used internally."""
|
||
|
|
return self.sock.fileno()
|
||
|
|
|
||
|
|
def write(self, buffer):
|
||
|
|
"""Write a string to the socket, doubling any IAC characters.
|
||
|
|
|
||
|
|
Can block if the connection is blocked. May raise
|
||
|
|
OSError if the connection is closed.
|
||
|
|
|
||
|
|
"""
|
||
|
|
if IAC in buffer:
|
||
|
|
buffer = buffer.replace(IAC, IAC+IAC)
|
||
|
|
sys.audit("telnetlib.Telnet.write", self, buffer)
|
||
|
|
self.msg("send %r", buffer)
|
||
|
|
self.sock.sendall(buffer)
|
||
|
|
|
||
|
|
def read_until(self, match, timeout=None):
|
||
|
|
"""Read until a given string is encountered or until timeout.
|
||
|
|
|
||
|
|
When no match is found, return whatever is available instead,
|
||
|
|
possibly the empty string. Raise EOFError if the connection
|
||
|
|
is closed and no cooked data is available.
|
||
|
|
|
||
|
|
"""
|
||
|
|
n = len(match)
|
||
|
|
self.process_rawq()
|
||
|
|
i = self.cookedq.find(match)
|
||
|
|
if i >= 0:
|
||
|
|
i = i+n
|
||
|
|
buf = self.cookedq[:i]
|
||
|
|
self.cookedq = self.cookedq[i:]
|
||
|
|
return buf
|
||
|
|
if timeout is not None:
|
||
|
|
deadline = _time() + timeout
|
||
|
|
with _TelnetSelector() as selector:
|
||
|
|
selector.register(self, selectors.EVENT_READ)
|
||
|
|
while not self.eof:
|
||
|
|
if selector.select(timeout):
|
||
|
|
i = max(0, len(self.cookedq)-n)
|
||
|
|
self.fill_rawq()
|
||
|
|
self.process_rawq()
|
||
|
|
i = self.cookedq.find(match, i)
|
||
|
|
if i >= 0:
|
||
|
|
i = i+n
|
||
|
|
buf = self.cookedq[:i]
|
||
|
|
self.cookedq = self.cookedq[i:]
|
||
|
|
return buf
|
||
|
|
if timeout is not None:
|
||
|
|
timeout = deadline - _time()
|
||
|
|
if timeout < 0:
|
||
|
|
break
|
||
|
|
return self.read_very_lazy()
|
||
|
|
|
||
|
|
def read_all(self):
|
||
|
|
"""Read all data until EOF; block until connection closed."""
|
||
|
|
self.process_rawq()
|
||
|
|
while not self.eof:
|
||
|
|
self.fill_rawq()
|
||
|
|
self.process_rawq()
|
||
|
|
buf = self.cookedq
|
||
|
|
self.cookedq = b''
|
||
|
|
return buf
|
||
|
|
|
||
|
|
def read_some(self):
|
||
|
|
"""Read at least one byte of cooked data unless EOF is hit.
|
||
|
|
|
||
|
|
Return b'' if EOF is hit. Block if no data is immediately
|
||
|
|
available.
|
||
|
|
|
||
|
|
"""
|
||
|
|
self.process_rawq()
|
||
|
|
while not self.cookedq and not self.eof:
|
||
|
|
self.fill_rawq()
|
||
|
|
self.process_rawq()
|
||
|
|
buf = self.cookedq
|
||
|
|
self.cookedq = b''
|
||
|
|
return buf
|
||
|
|
|
||
|
|
def read_very_eager(self):
|
||
|
|
"""Read everything that's possible without blocking in I/O (eager).
|
||
|
|
|
||
|
|
Raise EOFError if connection closed and no cooked data
|
||
|
|
available. Return b'' if no cooked data available otherwise.
|
||
|
|
Don't block unless in the midst of an IAC sequence.
|
||
|
|
|
||
|
|
"""
|
||
|
|
self.process_rawq()
|
||
|
|
while not self.eof and self.sock_avail():
|
||
|
|
self.fill_rawq()
|
||
|
|
self.process_rawq()
|
||
|
|
return self.read_very_lazy()
|
||
|
|
|
||
|
|
def read_eager(self):
|
||
|
|
"""Read readily available data.
|
||
|
|
|
||
|
|
Raise EOFError if connection closed and no cooked data
|
||
|
|
available. Return b'' if no cooked data available otherwise.
|
||
|
|
Don't block unless in the midst of an IAC sequence.
|
||
|
|
|
||
|
|
"""
|
||
|
|
self.process_rawq()
|
||
|
|
while not self.cookedq and not self.eof and self.sock_avail():
|
||
|
|
self.fill_rawq()
|
||
|
|
self.process_rawq()
|
||
|
|
return self.read_very_lazy()
|
||
|
|
|
||
|
|
def read_lazy(self):
|
||
|
|
"""Process and return data that's already in the queues (lazy).
|
||
|
|
|
||
|
|
Raise EOFError if connection closed and no data available.
|
||
|
|
Return b'' if no cooked data available otherwise. Don't block
|
||
|
|
unless in the midst of an IAC sequence.
|
||
|
|
|
||
|
|
"""
|
||
|
|
self.process_rawq()
|
||
|
|
return self.read_very_lazy()
|
||
|
|
|
||
|
|
def read_very_lazy(self):
|
||
|
|
"""Return any data available in the cooked queue (very lazy).
|
||
|
|
|
||
|
|
Raise EOFError if connection closed and no data available.
|
||
|
|
Return b'' if no cooked data available otherwise. Don't block.
|
||
|
|
|
||
|
|
"""
|
||
|
|
buf = self.cookedq
|
||
|
|
self.cookedq = b''
|
||
|
|
if not buf and self.eof and not self.rawq:
|
||
|
|
raise EOFError('telnet connection closed')
|
||
|
|
return buf
|
||
|
|
|
||
|
|
def read_sb_data(self):
|
||
|
|
"""Return any data available in the SB ... SE queue.
|
||
|
|
|
||
|
|
Return b'' if no SB ... SE available. Should only be called
|
||
|
|
after seeing a SB or SE command. When a new SB command is
|
||
|
|
found, old unread SB data will be discarded. Don't block.
|
||
|
|
|
||
|
|
"""
|
||
|
|
buf = self.sbdataq
|
||
|
|
self.sbdataq = b''
|
||
|
|
return buf
|
||
|
|
|
||
|
|
def set_option_negotiation_callback(self, callback):
|
||
|
|
"""Provide a callback function called after each receipt of a telnet option."""
|
||
|
|
self.option_callback = callback
|
||
|
|
|
||
|
|
def process_rawq(self):
|
||
|
|
"""Transfer from raw queue to cooked queue.
|
||
|
|
|
||
|
|
Set self.eof when connection is closed. Don't block unless in
|
||
|
|
the midst of an IAC sequence.
|
||
|
|
|
||
|
|
"""
|
||
|
|
buf = [b'', b'']
|
||
|
|
try:
|
||
|
|
while self.rawq:
|
||
|
|
c = self.rawq_getchar()
|
||
|
|
if not self.iacseq:
|
||
|
|
if c == theNULL:
|
||
|
|
continue
|
||
|
|
if c == b"\021":
|
||
|
|
continue
|
||
|
|
if c != IAC:
|
||
|
|
buf[self.sb] = buf[self.sb] + c
|
||
|
|
continue
|
||
|
|
else:
|
||
|
|
self.iacseq += c
|
||
|
|
elif len(self.iacseq) == 1:
|
||
|
|
# 'IAC: IAC CMD [OPTION only for WILL/WONT/DO/DONT]'
|
||
|
|
if c in (DO, DONT, WILL, WONT):
|
||
|
|
self.iacseq += c
|
||
|
|
continue
|
||
|
|
|
||
|
|
self.iacseq = b''
|
||
|
|
if c == IAC:
|
||
|
|
buf[self.sb] = buf[self.sb] + c
|
||
|
|
else:
|
||
|
|
if c == SB: # SB ... SE start.
|
||
|
|
self.sb = 1
|
||
|
|
self.sbdataq = b''
|
||
|
|
elif c == SE:
|
||
|
|
self.sb = 0
|
||
|
|
self.sbdataq = self.sbdataq + buf[1]
|
||
|
|
buf[1] = b''
|
||
|
|
if self.option_callback:
|
||
|
|
# Callback is supposed to look into
|
||
|
|
# the sbdataq
|
||
|
|
self.option_callback(self.sock, c, NOOPT)
|
||
|
|
else:
|
||
|
|
# We can't offer automatic processing of
|
||
|
|
# suboptions. Alas, we should not get any
|
||
|
|
# unless we did a WILL/DO before.
|
||
|
|
self.msg('IAC %d not recognized' % ord(c))
|
||
|
|
elif len(self.iacseq) == 2:
|
||
|
|
cmd = self.iacseq[1:2]
|
||
|
|
self.iacseq = b''
|
||
|
|
opt = c
|
||
|
|
if cmd in (DO, DONT):
|
||
|
|
self.msg('IAC %s %d',
|
||
|
|
cmd == DO and 'DO' or 'DONT', ord(opt))
|
||
|
|
if self.option_callback:
|
||
|
|
self.option_callback(self.sock, cmd, opt)
|
||
|
|
else:
|
||
|
|
self.sock.sendall(IAC + WONT + opt)
|
||
|
|
elif cmd in (WILL, WONT):
|
||
|
|
self.msg('IAC %s %d',
|
||
|
|
cmd == WILL and 'WILL' or 'WONT', ord(opt))
|
||
|
|
if self.option_callback:
|
||
|
|
self.option_callback(self.sock, cmd, opt)
|
||
|
|
else:
|
||
|
|
self.sock.sendall(IAC + DONT + opt)
|
||
|
|
except EOFError: # raised by self.rawq_getchar()
|
||
|
|
self.iacseq = b'' # Reset on EOF
|
||
|
|
self.sb = 0
|
||
|
|
pass
|
||
|
|
self.cookedq = self.cookedq + buf[0]
|
||
|
|
self.sbdataq = self.sbdataq + buf[1]
|
||
|
|
|
||
|
|
def rawq_getchar(self):
|
||
|
|
"""Get next char from raw queue.
|
||
|
|
|
||
|
|
Block if no data is immediately available. Raise EOFError
|
||
|
|
when connection is closed.
|
||
|
|
|
||
|
|
"""
|
||
|
|
if not self.rawq:
|
||
|
|
self.fill_rawq()
|
||
|
|
if self.eof:
|
||
|
|
raise EOFError
|
||
|
|
c = self.rawq[self.irawq:self.irawq+1]
|
||
|
|
self.irawq = self.irawq + 1
|
||
|
|
if self.irawq >= len(self.rawq):
|
||
|
|
self.rawq = b''
|
||
|
|
self.irawq = 0
|
||
|
|
return c
|
||
|
|
|
||
|
|
def fill_rawq(self):
|
||
|
|
"""Fill raw queue from exactly one recv() system call.
|
||
|
|
|
||
|
|
Block if no data is immediately available. Set self.eof when
|
||
|
|
connection is closed.
|
||
|
|
|
||
|
|
"""
|
||
|
|
if self.irawq >= len(self.rawq):
|
||
|
|
self.rawq = b''
|
||
|
|
self.irawq = 0
|
||
|
|
# The buffer size should be fairly small so as to avoid quadratic
|
||
|
|
# behavior in process_rawq() above
|
||
|
|
buf = self.sock.recv(50)
|
||
|
|
self.msg("recv %r", buf)
|
||
|
|
self.eof = (not buf)
|
||
|
|
self.rawq = self.rawq + buf
|
||
|
|
|
||
|
|
def sock_avail(self):
|
||
|
|
"""Test whether data is available on the socket."""
|
||
|
|
with _TelnetSelector() as selector:
|
||
|
|
selector.register(self, selectors.EVENT_READ)
|
||
|
|
return bool(selector.select(0))
|
||
|
|
|
||
|
|
def interact(self):
|
||
|
|
"""Interaction function, emulates a very dumb telnet client."""
|
||
|
|
if sys.platform == "win32":
|
||
|
|
self.mt_interact()
|
||
|
|
return
|
||
|
|
with _TelnetSelector() as selector:
|
||
|
|
selector.register(self, selectors.EVENT_READ)
|
||
|
|
selector.register(sys.stdin, selectors.EVENT_READ)
|
||
|
|
|
||
|
|
while True:
|
||
|
|
for key, events in selector.select():
|
||
|
|
if key.fileobj is self:
|
||
|
|
try:
|
||
|
|
text = self.read_eager()
|
||
|
|
except EOFError:
|
||
|
|
print('*** Connection closed by remote host ***')
|
||
|
|
return
|
||
|
|
if text:
|
||
|
|
sys.stdout.write(text.decode('ascii'))
|
||
|
|
sys.stdout.flush()
|
||
|
|
elif key.fileobj is sys.stdin:
|
||
|
|
line = sys.stdin.readline().encode('ascii')
|
||
|
|
if not line:
|
||
|
|
return
|
||
|
|
self.write(line)
|
||
|
|
|
||
|
|
def mt_interact(self):
|
||
|
|
"""Multithreaded version of interact()."""
|
||
|
|
import _thread
|
||
|
|
_thread.start_new_thread(self.listener, ())
|
||
|
|
while 1:
|
||
|
|
line = sys.stdin.readline()
|
||
|
|
if not line:
|
||
|
|
break
|
||
|
|
self.write(line.encode('ascii'))
|
||
|
|
|
||
|
|
def listener(self):
|
||
|
|
"""Helper for mt_interact() -- this executes in the other thread."""
|
||
|
|
while 1:
|
||
|
|
try:
|
||
|
|
data = self.read_eager()
|
||
|
|
except EOFError:
|
||
|
|
print('*** Connection closed by remote host ***')
|
||
|
|
return
|
||
|
|
if data:
|
||
|
|
sys.stdout.write(data.decode('ascii'))
|
||
|
|
else:
|
||
|
|
sys.stdout.flush()
|
||
|
|
|
||
|
|
def expect(self, list, timeout=None):
|
||
|
|
"""Read until one from a list of a regular expressions matches.
|
||
|
|
|
||
|
|
The first argument is a list of regular expressions, either
|
||
|
|
compiled (re.Pattern instances) or uncompiled (strings).
|
||
|
|
The optional second argument is a timeout, in seconds; default
|
||
|
|
is no timeout.
|
||
|
|
|
||
|
|
Return a tuple of three items: the index in the list of the
|
||
|
|
first regular expression that matches; the re.Match object
|
||
|
|
returned; and the text read up till and including the match.
|
||
|
|
|
||
|
|
If EOF is read and no text was read, raise EOFError.
|
||
|
|
Otherwise, when nothing matches, return (-1, None, text) where
|
||
|
|
text is the text received so far (may be the empty string if a
|
||
|
|
timeout happened).
|
||
|
|
|
||
|
|
If a regular expression ends with a greedy match (e.g. '.*')
|
||
|
|
or if more than one expression can match the same input, the
|
||
|
|
results are undeterministic, and may depend on the I/O timing.
|
||
|
|
|
||
|
|
"""
|
||
|
|
re = None
|
||
|
|
list = list[:]
|
||
|
|
indices = range(len(list))
|
||
|
|
for i in indices:
|
||
|
|
if not hasattr(list[i], "search"):
|
||
|
|
if not re: import re
|
||
|
|
list[i] = re.compile(list[i])
|
||
|
|
if timeout is not None:
|
||
|
|
deadline = _time() + timeout
|
||
|
|
with _TelnetSelector() as selector:
|
||
|
|
selector.register(self, selectors.EVENT_READ)
|
||
|
|
while not self.eof:
|
||
|
|
self.process_rawq()
|
||
|
|
for i in indices:
|
||
|
|
m = list[i].search(self.cookedq)
|
||
|
|
if m:
|
||
|
|
e = m.end()
|
||
|
|
text = self.cookedq[:e]
|
||
|
|
self.cookedq = self.cookedq[e:]
|
||
|
|
return (i, m, text)
|
||
|
|
if timeout is not None:
|
||
|
|
ready = selector.select(timeout)
|
||
|
|
timeout = deadline - _time()
|
||
|
|
if not ready:
|
||
|
|
if timeout < 0:
|
||
|
|
break
|
||
|
|
else:
|
||
|
|
continue
|
||
|
|
self.fill_rawq()
|
||
|
|
text = self.read_very_lazy()
|
||
|
|
if not text and self.eof:
|
||
|
|
raise EOFError
|
||
|
|
return (-1, None, text)
|
||
|
|
|
||
|
|
def __enter__(self):
|
||
|
|
return self
|
||
|
|
|
||
|
|
def __exit__(self, type, value, traceback):
|
||
|
|
self.close()
|
||
|
|
|
||
|
|
|
||
|
|
def test():
|
||
|
|
"""Test program for telnetlib.
|
||
|
|
|
||
|
|
Usage: python telnetlib.py [-d] ... [host [port]]
|
||
|
|
|
||
|
|
Default host is localhost; default port is 23.
|
||
|
|
|
||
|
|
"""
|
||
|
|
debuglevel = 0
|
||
|
|
while sys.argv[1:] and sys.argv[1] == '-d':
|
||
|
|
debuglevel = debuglevel+1
|
||
|
|
del sys.argv[1]
|
||
|
|
host = 'localhost'
|
||
|
|
if sys.argv[1:]:
|
||
|
|
host = sys.argv[1]
|
||
|
|
port = 0
|
||
|
|
if sys.argv[2:]:
|
||
|
|
portstr = sys.argv[2]
|
||
|
|
try:
|
||
|
|
port = int(portstr)
|
||
|
|
except ValueError:
|
||
|
|
port = socket.getservbyname(portstr, 'tcp')
|
||
|
|
with Telnet() as tn:
|
||
|
|
tn.set_debuglevel(debuglevel)
|
||
|
|
tn.open(host, port, timeout=0.5)
|
||
|
|
tn.interact()
|
||
|
|
|
||
|
|
if __name__ == '__main__':
|
||
|
|
test()
|