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diff --git a/lib/python2.7/telnetlib.py b/lib/python2.7/telnetlib.py
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+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('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 select.select() in order to
+wait until more data is available. Note that in this case,
+read_eager() may return '' 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 errno
+import sys
+import socket
+import select
+
+__all__ = ["Telnet"]
+
+# Tunable parameters
+DEBUGLEVEL = 0
+
+# Telnet protocol defaults
+TELNET_PORT = 23
+
+# Telnet protocol characters (don't change)
+IAC = chr(255) # "Interpret As Command"
+DONT = chr(254)
+DO = chr(253)
+WONT = chr(252)
+WILL = chr(251)
+theNULL = chr(0)
+
+SE = chr(240) # Subnegotiation End
+NOP = chr(241) # No Operation
+DM = chr(242) # Data Mark
+BRK = chr(243) # Break
+IP = chr(244) # Interrupt process
+AO = chr(245) # Abort output
+AYT = chr(246) # Are You There
+EC = chr(247) # Erase Character
+EL = chr(248) # Erase Line
+GA = chr(249) # Go Ahead
+SB = chr(250) # Subnegotiation Begin
+
+
+# Telnet protocol options code (don't change)
+# These ones all come from arpa/telnet.h
+BINARY = chr(0) # 8-bit data path
+ECHO = chr(1) # echo
+RCP = chr(2) # prepare to reconnect
+SGA = chr(3) # suppress go ahead
+NAMS = chr(4) # approximate message size
+STATUS = chr(5) # give status
+TM = chr(6) # timing mark
+RCTE = chr(7) # remote controlled transmission and echo
+NAOL = chr(8) # negotiate about output line width
+NAOP = chr(9) # negotiate about output page size
+NAOCRD = chr(10) # negotiate about CR disposition
+NAOHTS = chr(11) # negotiate about horizontal tabstops
+NAOHTD = chr(12) # negotiate about horizontal tab disposition
+NAOFFD = chr(13) # negotiate about formfeed disposition
+NAOVTS = chr(14) # negotiate about vertical tab stops
+NAOVTD = chr(15) # negotiate about vertical tab disposition
+NAOLFD = chr(16) # negotiate about output LF disposition
+XASCII = chr(17) # extended ascii character set
+LOGOUT = chr(18) # force logout
+BM = chr(19) # byte macro
+DET = chr(20) # data entry terminal
+SUPDUP = chr(21) # supdup protocol
+SUPDUPOUTPUT = chr(22) # supdup output
+SNDLOC = chr(23) # send location
+TTYPE = chr(24) # terminal type
+EOR = chr(25) # end or record
+TUID = chr(26) # TACACS user identification
+OUTMRK = chr(27) # output marking
+TTYLOC = chr(28) # terminal location number
+VT3270REGIME = chr(29) # 3270 regime
+X3PAD = chr(30) # X.3 PAD
+NAWS = chr(31) # window size
+TSPEED = chr(32) # terminal speed
+LFLOW = chr(33) # remote flow control
+LINEMODE = chr(34) # Linemode option
+XDISPLOC = chr(35) # X Display Location
+OLD_ENVIRON = chr(36) # Old - Environment variables
+AUTHENTICATION = chr(37) # Authenticate
+ENCRYPT = chr(38) # Encryption option
+NEW_ENVIRON = chr(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 = chr(40) # TN3270E
+XAUTH = chr(41) # XAUTH
+CHARSET = chr(42) # CHARSET
+RSP = chr(43) # Telnet Remote Serial Port
+COM_PORT_OPTION = chr(44) # Com Port Control Option
+SUPPRESS_LOCAL_ECHO = chr(45) # Telnet Suppress Local Echo
+TLS = chr(46) # Telnet Start TLS
+KERMIT = chr(47) # KERMIT
+SEND_URL = chr(48) # SEND-URL
+FORWARD_X = chr(49) # FORWARD_X
+PRAGMA_LOGON = chr(138) # TELOPT PRAGMA LOGON
+SSPI_LOGON = chr(139) # TELOPT SSPI LOGON
+PRAGMA_HEARTBEAT = chr(140) # TELOPT PRAGMA HEARTBEAT
+EXOPL = chr(255) # Extended-Options-List
+NOOPT = chr(0)
+
+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 = ''
+ self.irawq = 0
+ self.cookedq = ''
+ self.eof = 0
+ self.iacseq = '' # Buffer for IAC sequence.
+ self.sb = 0 # flag for SB and SE sequence.
+ self.sbdataq = ''
+ self.option_callback = None
+ self._has_poll = hasattr(select, 'poll')
+ 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
+ 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),
+ 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."""
+ if self.sock:
+ self.sock.close()
+ self.sock = 0
+ self.eof = 1
+ self.iacseq = ''
+ self.sb = 0
+
+ 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
+ socket.error if the connection is closed.
+
+ """
+ if IAC in buffer:
+ buffer = buffer.replace(IAC, IAC+IAC)
+ 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.
+
+ """
+ if self._has_poll:
+ return self._read_until_with_poll(match, timeout)
+ else:
+ return self._read_until_with_select(match, timeout)
+
+ def _read_until_with_poll(self, match, timeout):
+ """Read until a given string is encountered or until timeout.
+
+ This method uses select.poll() to implement the timeout.
+ """
+ n = len(match)
+ call_timeout = timeout
+ if timeout is not None:
+ from time import time
+ time_start = time()
+ self.process_rawq()
+ i = self.cookedq.find(match)
+ if i < 0:
+ poller = select.poll()
+ poll_in_or_priority_flags = select.POLLIN | select.POLLPRI
+ poller.register(self, poll_in_or_priority_flags)
+ while i < 0 and not self.eof:
+ try:
+ ready = poller.poll(call_timeout)
+ except select.error as e:
+ if e.errno == errno.EINTR:
+ if timeout is not None:
+ elapsed = time() - time_start
+ call_timeout = timeout-elapsed
+ continue
+ raise
+ for fd, mode in ready:
+ if mode & poll_in_or_priority_flags:
+ i = max(0, len(self.cookedq)-n)
+ self.fill_rawq()
+ self.process_rawq()
+ i = self.cookedq.find(match, i)
+ if timeout is not None:
+ elapsed = time() - time_start
+ if elapsed >= timeout:
+ break
+ call_timeout = timeout-elapsed
+ poller.unregister(self)
+ if i >= 0:
+ i = i + n
+ buf = self.cookedq[:i]
+ self.cookedq = self.cookedq[i:]
+ return buf
+ return self.read_very_lazy()
+
+ def _read_until_with_select(self, match, timeout=None):
+ """Read until a given string is encountered or until timeout.
+
+ The timeout is implemented using select.select().
+ """
+ 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
+ s_reply = ([self], [], [])
+ s_args = s_reply
+ if timeout is not None:
+ s_args = s_args + (timeout,)
+ from time import time
+ time_start = time()
+ while not self.eof and select.select(*s_args) == s_reply:
+ 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:
+ elapsed = time() - time_start
+ if elapsed >= timeout:
+ break
+ s_args = s_reply + (timeout-elapsed,)
+ 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 = ''
+ return buf
+
+ def read_some(self):
+ """Read at least one byte of cooked data unless EOF is hit.
+
+ Return '' 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 = ''
+ 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 '' 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 '' 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 '' 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 '' if no cooked data available otherwise. Don't block.
+
+ """
+ buf = self.cookedq
+ self.cookedq = ''
+ 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 '' 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 = ''
+ 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 = ['', '']
+ try:
+ while self.rawq:
+ c = self.rawq_getchar()
+ if not self.iacseq:
+ if c == theNULL:
+ continue
+ if c == "\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 = ''
+ if c == IAC:
+ buf[self.sb] = buf[self.sb] + c
+ else:
+ if c == SB: # SB ... SE start.
+ self.sb = 1
+ self.sbdataq = ''
+ elif c == SE:
+ self.sb = 0
+ self.sbdataq = self.sbdataq + buf[1]
+ buf[1] = ''
+ 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]
+ self.iacseq = ''
+ 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 = '' # 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 = self.irawq + 1
+ if self.irawq >= len(self.rawq):
+ self.rawq = ''
+ 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 = ''
+ 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."""
+ return select.select([self], [], [], 0) == ([self], [], [])
+
+ def interact(self):
+ """Interaction function, emulates a very dumb telnet client."""
+ if sys.platform == "win32":
+ self.mt_interact()
+ return
+ while 1:
+ rfd, wfd, xfd = select.select([self, sys.stdin], [], [])
+ if self in rfd:
+ try:
+ text = self.read_eager()
+ except EOFError:
+ print '*** Connection closed by remote host ***'
+ break
+ if text:
+ sys.stdout.write(text)
+ sys.stdout.flush()
+ if sys.stdin in rfd:
+ line = sys.stdin.readline()
+ if not line:
+ break
+ 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)
+
+ 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)
+ 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.RegexObject 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 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.
+
+ """
+ if self._has_poll:
+ return self._expect_with_poll(list, timeout)
+ else:
+ return self._expect_with_select(list, timeout)
+
+ def _expect_with_poll(self, expect_list, timeout=None):
+ """Read until one from a list of a regular expressions matches.
+
+ This method uses select.poll() to implement the timeout.
+ """
+ re = None
+ expect_list = expect_list[:]
+ indices = range(len(expect_list))
+ for i in indices:
+ if not hasattr(expect_list[i], "search"):
+ if not re: import re
+ expect_list[i] = re.compile(expect_list[i])
+ call_timeout = timeout
+ if timeout is not None:
+ from time import time
+ time_start = time()
+ self.process_rawq()
+ m = None
+ for i in indices:
+ m = expect_list[i].search(self.cookedq)
+ if m:
+ e = m.end()
+ text = self.cookedq[:e]
+ self.cookedq = self.cookedq[e:]
+ break
+ if not m:
+ poller = select.poll()
+ poll_in_or_priority_flags = select.POLLIN | select.POLLPRI
+ poller.register(self, poll_in_or_priority_flags)
+ while not m and not self.eof:
+ try:
+ ready = poller.poll(call_timeout)
+ except select.error as e:
+ if e.errno == errno.EINTR:
+ if timeout is not None:
+ elapsed = time() - time_start
+ call_timeout = timeout-elapsed
+ continue
+ raise
+ for fd, mode in ready:
+ if mode & poll_in_or_priority_flags:
+ self.fill_rawq()
+ self.process_rawq()
+ for i in indices:
+ m = expect_list[i].search(self.cookedq)
+ if m:
+ e = m.end()
+ text = self.cookedq[:e]
+ self.cookedq = self.cookedq[e:]
+ break
+ if timeout is not None:
+ elapsed = time() - time_start
+ if elapsed >= timeout:
+ break
+ call_timeout = timeout-elapsed
+ poller.unregister(self)
+ if m:
+ return (i, m, text)
+ text = self.read_very_lazy()
+ if not text and self.eof:
+ raise EOFError
+ return (-1, None, text)
+
+ def _expect_with_select(self, list, timeout=None):
+ """Read until one from a list of a regular expressions matches.
+
+ The timeout is implemented using select.select().
+ """
+ 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:
+ from time import time
+ time_start = time()
+ while 1:
+ 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 self.eof:
+ break
+ if timeout is not None:
+ elapsed = time() - time_start
+ if elapsed >= timeout:
+ break
+ s_args = ([self.fileno()], [], [], timeout-elapsed)
+ r, w, x = select.select(*s_args)
+ if not r:
+ break
+ self.fill_rawq()
+ text = self.read_very_lazy()
+ if not text and self.eof:
+ raise EOFError
+ return (-1, None, text)
+
+
+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')
+ tn = Telnet()
+ tn.set_debuglevel(debuglevel)
+ tn.open(host, port, timeout=0.5)
+ tn.interact()
+ tn.close()
+
+if __name__ == '__main__':
+ test()