953 lines
30 KiB
Python
953 lines
30 KiB
Python
#
|
||
# A higher level module for using sockets (or Windows named pipes)
|
||
#
|
||
# multiprocessing/connection.py
|
||
#
|
||
# Copyright (c) 2006-2008, R Oudkerk
|
||
# Licensed to PSF under a Contributor Agreement.
|
||
#
|
||
|
||
__all__ = [ 'Client', 'Listener', 'Pipe', 'wait' ]
|
||
|
||
import io
|
||
import os
|
||
import sys
|
||
import socket
|
||
import struct
|
||
import time
|
||
import tempfile
|
||
import itertools
|
||
|
||
import _multiprocessing
|
||
|
||
from . import reduction
|
||
from . import util
|
||
|
||
from . import AuthenticationError, BufferTooShort
|
||
from .reduction import ForkingPickler
|
||
|
||
try:
|
||
import _winapi
|
||
from _winapi import WAIT_OBJECT_0, WAIT_ABANDONED_0, WAIT_TIMEOUT, INFINITE
|
||
except ImportError:
|
||
if sys.platform == 'win32':
|
||
raise
|
||
_winapi = None
|
||
|
||
#
|
||
#
|
||
#
|
||
|
||
BUFSIZE = 8192
|
||
# A very generous timeout when it comes to local connections...
|
||
CONNECTION_TIMEOUT = 20.
|
||
|
||
_mmap_counter = itertools.count()
|
||
|
||
default_family = 'AF_INET'
|
||
families = ['AF_INET']
|
||
|
||
if hasattr(socket, 'AF_UNIX'):
|
||
default_family = 'AF_UNIX'
|
||
families += ['AF_UNIX']
|
||
|
||
if sys.platform == 'win32':
|
||
default_family = 'AF_PIPE'
|
||
families += ['AF_PIPE']
|
||
|
||
|
||
def _init_timeout(timeout=CONNECTION_TIMEOUT):
|
||
return time.time() + timeout
|
||
|
||
def _check_timeout(t):
|
||
return time.time() > t
|
||
|
||
#
|
||
#
|
||
#
|
||
|
||
def arbitrary_address(family):
|
||
'''
|
||
Return an arbitrary free address for the given family
|
||
'''
|
||
if family == 'AF_INET':
|
||
return ('localhost', 0)
|
||
elif family == 'AF_UNIX':
|
||
return tempfile.mktemp(prefix='listener-', dir=util.get_temp_dir())
|
||
elif family == 'AF_PIPE':
|
||
return tempfile.mktemp(prefix=r'\\.\pipe\pyc-%d-%d-' %
|
||
(os.getpid(), next(_mmap_counter)), dir="")
|
||
else:
|
||
raise ValueError('unrecognized family')
|
||
|
||
def _validate_family(family):
|
||
'''
|
||
Checks if the family is valid for the current environment.
|
||
'''
|
||
if sys.platform != 'win32' and family == 'AF_PIPE':
|
||
raise ValueError('Family %s is not recognized.' % family)
|
||
|
||
if sys.platform == 'win32' and family == 'AF_UNIX':
|
||
# double check
|
||
if not hasattr(socket, family):
|
||
raise ValueError('Family %s is not recognized.' % family)
|
||
|
||
def address_type(address):
|
||
'''
|
||
Return the types of the address
|
||
|
||
This can be 'AF_INET', 'AF_UNIX', or 'AF_PIPE'
|
||
'''
|
||
if type(address) == tuple:
|
||
return 'AF_INET'
|
||
elif type(address) is str and address.startswith('\\\\'):
|
||
return 'AF_PIPE'
|
||
elif type(address) is str:
|
||
return 'AF_UNIX'
|
||
else:
|
||
raise ValueError('address type of %r unrecognized' % address)
|
||
|
||
#
|
||
# Connection classes
|
||
#
|
||
|
||
class _ConnectionBase:
|
||
_handle = None
|
||
|
||
def __init__(self, handle, readable=True, writable=True):
|
||
handle = handle.__index__()
|
||
if handle < 0:
|
||
raise ValueError("invalid handle")
|
||
if not readable and not writable:
|
||
raise ValueError(
|
||
"at least one of `readable` and `writable` must be True")
|
||
self._handle = handle
|
||
self._readable = readable
|
||
self._writable = writable
|
||
|
||
# XXX should we use util.Finalize instead of a __del__?
|
||
|
||
def __del__(self):
|
||
if self._handle is not None:
|
||
self._close()
|
||
|
||
def _check_closed(self):
|
||
if self._handle is None:
|
||
raise OSError("handle is closed")
|
||
|
||
def _check_readable(self):
|
||
if not self._readable:
|
||
raise OSError("connection is write-only")
|
||
|
||
def _check_writable(self):
|
||
if not self._writable:
|
||
raise OSError("connection is read-only")
|
||
|
||
def _bad_message_length(self):
|
||
if self._writable:
|
||
self._readable = False
|
||
else:
|
||
self.close()
|
||
raise OSError("bad message length")
|
||
|
||
@property
|
||
def closed(self):
|
||
"""True if the connection is closed"""
|
||
return self._handle is None
|
||
|
||
@property
|
||
def readable(self):
|
||
"""True if the connection is readable"""
|
||
return self._readable
|
||
|
||
@property
|
||
def writable(self):
|
||
"""True if the connection is writable"""
|
||
return self._writable
|
||
|
||
def fileno(self):
|
||
"""File descriptor or handle of the connection"""
|
||
self._check_closed()
|
||
return self._handle
|
||
|
||
def close(self):
|
||
"""Close the connection"""
|
||
if self._handle is not None:
|
||
try:
|
||
self._close()
|
||
finally:
|
||
self._handle = None
|
||
|
||
def send_bytes(self, buf, offset=0, size=None):
|
||
"""Send the bytes data from a bytes-like object"""
|
||
self._check_closed()
|
||
self._check_writable()
|
||
m = memoryview(buf)
|
||
# HACK for byte-indexing of non-bytewise buffers (e.g. array.array)
|
||
if m.itemsize > 1:
|
||
m = memoryview(bytes(m))
|
||
n = len(m)
|
||
if offset < 0:
|
||
raise ValueError("offset is negative")
|
||
if n < offset:
|
||
raise ValueError("buffer length < offset")
|
||
if size is None:
|
||
size = n - offset
|
||
elif size < 0:
|
||
raise ValueError("size is negative")
|
||
elif offset + size > n:
|
||
raise ValueError("buffer length < offset + size")
|
||
self._send_bytes(m[offset:offset + size])
|
||
|
||
def send(self, obj):
|
||
"""Send a (picklable) object"""
|
||
self._check_closed()
|
||
self._check_writable()
|
||
self._send_bytes(ForkingPickler.dumps(obj))
|
||
|
||
def recv_bytes(self, maxlength=None):
|
||
"""
|
||
Receive bytes data as a bytes object.
|
||
"""
|
||
self._check_closed()
|
||
self._check_readable()
|
||
if maxlength is not None and maxlength < 0:
|
||
raise ValueError("negative maxlength")
|
||
buf = self._recv_bytes(maxlength)
|
||
if buf is None:
|
||
self._bad_message_length()
|
||
return buf.getvalue()
|
||
|
||
def recv_bytes_into(self, buf, offset=0):
|
||
"""
|
||
Receive bytes data into a writeable bytes-like object.
|
||
Return the number of bytes read.
|
||
"""
|
||
self._check_closed()
|
||
self._check_readable()
|
||
with memoryview(buf) as m:
|
||
# Get bytesize of arbitrary buffer
|
||
itemsize = m.itemsize
|
||
bytesize = itemsize * len(m)
|
||
if offset < 0:
|
||
raise ValueError("negative offset")
|
||
elif offset > bytesize:
|
||
raise ValueError("offset too large")
|
||
result = self._recv_bytes()
|
||
size = result.tell()
|
||
if bytesize < offset + size:
|
||
raise BufferTooShort(result.getvalue())
|
||
# Message can fit in dest
|
||
result.seek(0)
|
||
result.readinto(m[offset // itemsize :
|
||
(offset + size) // itemsize])
|
||
return size
|
||
|
||
def recv(self):
|
||
"""Receive a (picklable) object"""
|
||
self._check_closed()
|
||
self._check_readable()
|
||
buf = self._recv_bytes()
|
||
return ForkingPickler.loads(buf.getbuffer())
|
||
|
||
def poll(self, timeout=0.0):
|
||
"""Whether there is any input available to be read"""
|
||
self._check_closed()
|
||
self._check_readable()
|
||
return self._poll(timeout)
|
||
|
||
def __enter__(self):
|
||
return self
|
||
|
||
def __exit__(self, exc_type, exc_value, exc_tb):
|
||
self.close()
|
||
|
||
|
||
if _winapi:
|
||
|
||
class PipeConnection(_ConnectionBase):
|
||
"""
|
||
Connection class based on a Windows named pipe.
|
||
Overlapped I/O is used, so the handles must have been created
|
||
with FILE_FLAG_OVERLAPPED.
|
||
"""
|
||
_got_empty_message = False
|
||
|
||
def _close(self, _CloseHandle=_winapi.CloseHandle):
|
||
_CloseHandle(self._handle)
|
||
|
||
def _send_bytes(self, buf):
|
||
ov, err = _winapi.WriteFile(self._handle, buf, overlapped=True)
|
||
try:
|
||
if err == _winapi.ERROR_IO_PENDING:
|
||
waitres = _winapi.WaitForMultipleObjects(
|
||
[ov.event], False, INFINITE)
|
||
assert waitres == WAIT_OBJECT_0
|
||
except:
|
||
ov.cancel()
|
||
raise
|
||
finally:
|
||
nwritten, err = ov.GetOverlappedResult(True)
|
||
assert err == 0
|
||
assert nwritten == len(buf)
|
||
|
||
def _recv_bytes(self, maxsize=None):
|
||
if self._got_empty_message:
|
||
self._got_empty_message = False
|
||
return io.BytesIO()
|
||
else:
|
||
bsize = 128 if maxsize is None else min(maxsize, 128)
|
||
try:
|
||
ov, err = _winapi.ReadFile(self._handle, bsize,
|
||
overlapped=True)
|
||
try:
|
||
if err == _winapi.ERROR_IO_PENDING:
|
||
waitres = _winapi.WaitForMultipleObjects(
|
||
[ov.event], False, INFINITE)
|
||
assert waitres == WAIT_OBJECT_0
|
||
except:
|
||
ov.cancel()
|
||
raise
|
||
finally:
|
||
nread, err = ov.GetOverlappedResult(True)
|
||
if err == 0:
|
||
f = io.BytesIO()
|
||
f.write(ov.getbuffer())
|
||
return f
|
||
elif err == _winapi.ERROR_MORE_DATA:
|
||
return self._get_more_data(ov, maxsize)
|
||
except OSError as e:
|
||
if e.winerror == _winapi.ERROR_BROKEN_PIPE:
|
||
raise EOFError
|
||
else:
|
||
raise
|
||
raise RuntimeError("shouldn't get here; expected KeyboardInterrupt")
|
||
|
||
def _poll(self, timeout):
|
||
if (self._got_empty_message or
|
||
_winapi.PeekNamedPipe(self._handle)[0] != 0):
|
||
return True
|
||
return bool(wait([self], timeout))
|
||
|
||
def _get_more_data(self, ov, maxsize):
|
||
buf = ov.getbuffer()
|
||
f = io.BytesIO()
|
||
f.write(buf)
|
||
left = _winapi.PeekNamedPipe(self._handle)[1]
|
||
assert left > 0
|
||
if maxsize is not None and len(buf) + left > maxsize:
|
||
self._bad_message_length()
|
||
ov, err = _winapi.ReadFile(self._handle, left, overlapped=True)
|
||
rbytes, err = ov.GetOverlappedResult(True)
|
||
assert err == 0
|
||
assert rbytes == left
|
||
f.write(ov.getbuffer())
|
||
return f
|
||
|
||
|
||
class Connection(_ConnectionBase):
|
||
"""
|
||
Connection class based on an arbitrary file descriptor (Unix only), or
|
||
a socket handle (Windows).
|
||
"""
|
||
|
||
if _winapi:
|
||
def _close(self, _close=_multiprocessing.closesocket):
|
||
_close(self._handle)
|
||
_write = _multiprocessing.send
|
||
_read = _multiprocessing.recv
|
||
else:
|
||
def _close(self, _close=os.close):
|
||
_close(self._handle)
|
||
_write = os.write
|
||
_read = os.read
|
||
|
||
def _send(self, buf, write=_write):
|
||
remaining = len(buf)
|
||
while True:
|
||
n = write(self._handle, buf)
|
||
remaining -= n
|
||
if remaining == 0:
|
||
break
|
||
buf = buf[n:]
|
||
|
||
def _recv(self, size, read=_read):
|
||
buf = io.BytesIO()
|
||
handle = self._handle
|
||
remaining = size
|
||
while remaining > 0:
|
||
chunk = read(handle, remaining)
|
||
n = len(chunk)
|
||
if n == 0:
|
||
if remaining == size:
|
||
raise EOFError
|
||
else:
|
||
raise OSError("got end of file during message")
|
||
buf.write(chunk)
|
||
remaining -= n
|
||
return buf
|
||
|
||
def _send_bytes(self, buf):
|
||
n = len(buf)
|
||
# For wire compatibility with 3.2 and lower
|
||
header = struct.pack("!i", n)
|
||
if n > 16384:
|
||
# The payload is large so Nagle's algorithm won't be triggered
|
||
# and we'd better avoid the cost of concatenation.
|
||
self._send(header)
|
||
self._send(buf)
|
||
else:
|
||
# Issue # 20540: concatenate before sending, to avoid delays due
|
||
# to Nagle's algorithm on a TCP socket.
|
||
# Also note we want to avoid sending a 0-length buffer separately,
|
||
# to avoid "broken pipe" errors if the other end closed the pipe.
|
||
self._send(header + buf)
|
||
|
||
def _recv_bytes(self, maxsize=None):
|
||
buf = self._recv(4)
|
||
size, = struct.unpack("!i", buf.getvalue())
|
||
if maxsize is not None and size > maxsize:
|
||
return None
|
||
return self._recv(size)
|
||
|
||
def _poll(self, timeout):
|
||
r = wait([self], timeout)
|
||
return bool(r)
|
||
|
||
|
||
#
|
||
# Public functions
|
||
#
|
||
|
||
class Listener(object):
|
||
'''
|
||
Returns a listener object.
|
||
|
||
This is a wrapper for a bound socket which is 'listening' for
|
||
connections, or for a Windows named pipe.
|
||
'''
|
||
def __init__(self, address=None, family=None, backlog=1, authkey=None):
|
||
family = family or (address and address_type(address)) \
|
||
or default_family
|
||
address = address or arbitrary_address(family)
|
||
|
||
_validate_family(family)
|
||
if family == 'AF_PIPE':
|
||
self._listener = PipeListener(address, backlog)
|
||
else:
|
||
self._listener = SocketListener(address, family, backlog)
|
||
|
||
if authkey is not None and not isinstance(authkey, bytes):
|
||
raise TypeError('authkey should be a byte string')
|
||
|
||
self._authkey = authkey
|
||
|
||
def accept(self):
|
||
'''
|
||
Accept a connection on the bound socket or named pipe of `self`.
|
||
|
||
Returns a `Connection` object.
|
||
'''
|
||
if self._listener is None:
|
||
raise OSError('listener is closed')
|
||
c = self._listener.accept()
|
||
if self._authkey:
|
||
deliver_challenge(c, self._authkey)
|
||
answer_challenge(c, self._authkey)
|
||
return c
|
||
|
||
def close(self):
|
||
'''
|
||
Close the bound socket or named pipe of `self`.
|
||
'''
|
||
listener = self._listener
|
||
if listener is not None:
|
||
self._listener = None
|
||
listener.close()
|
||
|
||
address = property(lambda self: self._listener._address)
|
||
last_accepted = property(lambda self: self._listener._last_accepted)
|
||
|
||
def __enter__(self):
|
||
return self
|
||
|
||
def __exit__(self, exc_type, exc_value, exc_tb):
|
||
self.close()
|
||
|
||
|
||
def Client(address, family=None, authkey=None):
|
||
'''
|
||
Returns a connection to the address of a `Listener`
|
||
'''
|
||
family = family or address_type(address)
|
||
_validate_family(family)
|
||
if family == 'AF_PIPE':
|
||
c = PipeClient(address)
|
||
else:
|
||
c = SocketClient(address)
|
||
|
||
if authkey is not None and not isinstance(authkey, bytes):
|
||
raise TypeError('authkey should be a byte string')
|
||
|
||
if authkey is not None:
|
||
answer_challenge(c, authkey)
|
||
deliver_challenge(c, authkey)
|
||
|
||
return c
|
||
|
||
|
||
if sys.platform != 'win32':
|
||
|
||
def Pipe(duplex=True):
|
||
'''
|
||
Returns pair of connection objects at either end of a pipe
|
||
'''
|
||
if duplex:
|
||
s1, s2 = socket.socketpair()
|
||
s1.setblocking(True)
|
||
s2.setblocking(True)
|
||
c1 = Connection(s1.detach())
|
||
c2 = Connection(s2.detach())
|
||
else:
|
||
fd1, fd2 = os.pipe()
|
||
c1 = Connection(fd1, writable=False)
|
||
c2 = Connection(fd2, readable=False)
|
||
|
||
return c1, c2
|
||
|
||
else:
|
||
|
||
def Pipe(duplex=True):
|
||
'''
|
||
Returns pair of connection objects at either end of a pipe
|
||
'''
|
||
address = arbitrary_address('AF_PIPE')
|
||
if duplex:
|
||
openmode = _winapi.PIPE_ACCESS_DUPLEX
|
||
access = _winapi.GENERIC_READ | _winapi.GENERIC_WRITE
|
||
obsize, ibsize = BUFSIZE, BUFSIZE
|
||
else:
|
||
openmode = _winapi.PIPE_ACCESS_INBOUND
|
||
access = _winapi.GENERIC_WRITE
|
||
obsize, ibsize = 0, BUFSIZE
|
||
|
||
h1 = _winapi.CreateNamedPipe(
|
||
address, openmode | _winapi.FILE_FLAG_OVERLAPPED |
|
||
_winapi.FILE_FLAG_FIRST_PIPE_INSTANCE,
|
||
_winapi.PIPE_TYPE_MESSAGE | _winapi.PIPE_READMODE_MESSAGE |
|
||
_winapi.PIPE_WAIT,
|
||
1, obsize, ibsize, _winapi.NMPWAIT_WAIT_FOREVER,
|
||
# default security descriptor: the handle cannot be inherited
|
||
_winapi.NULL
|
||
)
|
||
h2 = _winapi.CreateFile(
|
||
address, access, 0, _winapi.NULL, _winapi.OPEN_EXISTING,
|
||
_winapi.FILE_FLAG_OVERLAPPED, _winapi.NULL
|
||
)
|
||
_winapi.SetNamedPipeHandleState(
|
||
h2, _winapi.PIPE_READMODE_MESSAGE, None, None
|
||
)
|
||
|
||
overlapped = _winapi.ConnectNamedPipe(h1, overlapped=True)
|
||
_, err = overlapped.GetOverlappedResult(True)
|
||
assert err == 0
|
||
|
||
c1 = PipeConnection(h1, writable=duplex)
|
||
c2 = PipeConnection(h2, readable=duplex)
|
||
|
||
return c1, c2
|
||
|
||
#
|
||
# Definitions for connections based on sockets
|
||
#
|
||
|
||
class SocketListener(object):
|
||
'''
|
||
Representation of a socket which is bound to an address and listening
|
||
'''
|
||
def __init__(self, address, family, backlog=1):
|
||
self._socket = socket.socket(getattr(socket, family))
|
||
try:
|
||
# SO_REUSEADDR has different semantics on Windows (issue #2550).
|
||
if os.name == 'posix':
|
||
self._socket.setsockopt(socket.SOL_SOCKET,
|
||
socket.SO_REUSEADDR, 1)
|
||
self._socket.setblocking(True)
|
||
self._socket.bind(address)
|
||
self._socket.listen(backlog)
|
||
self._address = self._socket.getsockname()
|
||
except OSError:
|
||
self._socket.close()
|
||
raise
|
||
self._family = family
|
||
self._last_accepted = None
|
||
|
||
if family == 'AF_UNIX':
|
||
self._unlink = util.Finalize(
|
||
self, os.unlink, args=(address,), exitpriority=0
|
||
)
|
||
else:
|
||
self._unlink = None
|
||
|
||
def accept(self):
|
||
s, self._last_accepted = self._socket.accept()
|
||
s.setblocking(True)
|
||
return Connection(s.detach())
|
||
|
||
def close(self):
|
||
try:
|
||
self._socket.close()
|
||
finally:
|
||
unlink = self._unlink
|
||
if unlink is not None:
|
||
self._unlink = None
|
||
unlink()
|
||
|
||
|
||
def SocketClient(address):
|
||
'''
|
||
Return a connection object connected to the socket given by `address`
|
||
'''
|
||
family = address_type(address)
|
||
with socket.socket( getattr(socket, family) ) as s:
|
||
s.setblocking(True)
|
||
s.connect(address)
|
||
return Connection(s.detach())
|
||
|
||
#
|
||
# Definitions for connections based on named pipes
|
||
#
|
||
|
||
if sys.platform == 'win32':
|
||
|
||
class PipeListener(object):
|
||
'''
|
||
Representation of a named pipe
|
||
'''
|
||
def __init__(self, address, backlog=None):
|
||
self._address = address
|
||
self._handle_queue = [self._new_handle(first=True)]
|
||
|
||
self._last_accepted = None
|
||
util.sub_debug('listener created with address=%r', self._address)
|
||
self.close = util.Finalize(
|
||
self, PipeListener._finalize_pipe_listener,
|
||
args=(self._handle_queue, self._address), exitpriority=0
|
||
)
|
||
|
||
def _new_handle(self, first=False):
|
||
flags = _winapi.PIPE_ACCESS_DUPLEX | _winapi.FILE_FLAG_OVERLAPPED
|
||
if first:
|
||
flags |= _winapi.FILE_FLAG_FIRST_PIPE_INSTANCE
|
||
return _winapi.CreateNamedPipe(
|
||
self._address, flags,
|
||
_winapi.PIPE_TYPE_MESSAGE | _winapi.PIPE_READMODE_MESSAGE |
|
||
_winapi.PIPE_WAIT,
|
||
_winapi.PIPE_UNLIMITED_INSTANCES, BUFSIZE, BUFSIZE,
|
||
_winapi.NMPWAIT_WAIT_FOREVER, _winapi.NULL
|
||
)
|
||
|
||
def accept(self):
|
||
self._handle_queue.append(self._new_handle())
|
||
handle = self._handle_queue.pop(0)
|
||
try:
|
||
ov = _winapi.ConnectNamedPipe(handle, overlapped=True)
|
||
except OSError as e:
|
||
if e.winerror != _winapi.ERROR_NO_DATA:
|
||
raise
|
||
# ERROR_NO_DATA can occur if a client has already connected,
|
||
# written data and then disconnected -- see Issue 14725.
|
||
else:
|
||
try:
|
||
res = _winapi.WaitForMultipleObjects(
|
||
[ov.event], False, INFINITE)
|
||
except:
|
||
ov.cancel()
|
||
_winapi.CloseHandle(handle)
|
||
raise
|
||
finally:
|
||
_, err = ov.GetOverlappedResult(True)
|
||
assert err == 0
|
||
return PipeConnection(handle)
|
||
|
||
@staticmethod
|
||
def _finalize_pipe_listener(queue, address):
|
||
util.sub_debug('closing listener with address=%r', address)
|
||
for handle in queue:
|
||
_winapi.CloseHandle(handle)
|
||
|
||
def PipeClient(address):
|
||
'''
|
||
Return a connection object connected to the pipe given by `address`
|
||
'''
|
||
t = _init_timeout()
|
||
while 1:
|
||
try:
|
||
_winapi.WaitNamedPipe(address, 1000)
|
||
h = _winapi.CreateFile(
|
||
address, _winapi.GENERIC_READ | _winapi.GENERIC_WRITE,
|
||
0, _winapi.NULL, _winapi.OPEN_EXISTING,
|
||
_winapi.FILE_FLAG_OVERLAPPED, _winapi.NULL
|
||
)
|
||
except OSError as e:
|
||
if e.winerror not in (_winapi.ERROR_SEM_TIMEOUT,
|
||
_winapi.ERROR_PIPE_BUSY) or _check_timeout(t):
|
||
raise
|
||
else:
|
||
break
|
||
else:
|
||
raise
|
||
|
||
_winapi.SetNamedPipeHandleState(
|
||
h, _winapi.PIPE_READMODE_MESSAGE, None, None
|
||
)
|
||
return PipeConnection(h)
|
||
|
||
#
|
||
# Authentication stuff
|
||
#
|
||
|
||
MESSAGE_LENGTH = 20
|
||
|
||
CHALLENGE = b'#CHALLENGE#'
|
||
WELCOME = b'#WELCOME#'
|
||
FAILURE = b'#FAILURE#'
|
||
|
||
def deliver_challenge(connection, authkey):
|
||
import hmac
|
||
assert isinstance(authkey, bytes)
|
||
message = os.urandom(MESSAGE_LENGTH)
|
||
connection.send_bytes(CHALLENGE + message)
|
||
digest = hmac.new(authkey, message, 'md5').digest()
|
||
response = connection.recv_bytes(256) # reject large message
|
||
if response == digest:
|
||
connection.send_bytes(WELCOME)
|
||
else:
|
||
connection.send_bytes(FAILURE)
|
||
raise AuthenticationError('digest received was wrong')
|
||
|
||
def answer_challenge(connection, authkey):
|
||
import hmac
|
||
assert isinstance(authkey, bytes)
|
||
message = connection.recv_bytes(256) # reject large message
|
||
assert message[:len(CHALLENGE)] == CHALLENGE, 'message = %r' % message
|
||
message = message[len(CHALLENGE):]
|
||
digest = hmac.new(authkey, message, 'md5').digest()
|
||
connection.send_bytes(digest)
|
||
response = connection.recv_bytes(256) # reject large message
|
||
if response != WELCOME:
|
||
raise AuthenticationError('digest sent was rejected')
|
||
|
||
#
|
||
# Support for using xmlrpclib for serialization
|
||
#
|
||
|
||
class ConnectionWrapper(object):
|
||
def __init__(self, conn, dumps, loads):
|
||
self._conn = conn
|
||
self._dumps = dumps
|
||
self._loads = loads
|
||
for attr in ('fileno', 'close', 'poll', 'recv_bytes', 'send_bytes'):
|
||
obj = getattr(conn, attr)
|
||
setattr(self, attr, obj)
|
||
def send(self, obj):
|
||
s = self._dumps(obj)
|
||
self._conn.send_bytes(s)
|
||
def recv(self):
|
||
s = self._conn.recv_bytes()
|
||
return self._loads(s)
|
||
|
||
def _xml_dumps(obj):
|
||
return xmlrpclib.dumps((obj,), None, None, None, 1).encode('utf-8')
|
||
|
||
def _xml_loads(s):
|
||
(obj,), method = xmlrpclib.loads(s.decode('utf-8'))
|
||
return obj
|
||
|
||
class XmlListener(Listener):
|
||
def accept(self):
|
||
global xmlrpclib
|
||
import xmlrpc.client as xmlrpclib
|
||
obj = Listener.accept(self)
|
||
return ConnectionWrapper(obj, _xml_dumps, _xml_loads)
|
||
|
||
def XmlClient(*args, **kwds):
|
||
global xmlrpclib
|
||
import xmlrpc.client as xmlrpclib
|
||
return ConnectionWrapper(Client(*args, **kwds), _xml_dumps, _xml_loads)
|
||
|
||
#
|
||
# Wait
|
||
#
|
||
|
||
if sys.platform == 'win32':
|
||
|
||
def _exhaustive_wait(handles, timeout):
|
||
# Return ALL handles which are currently signalled. (Only
|
||
# returning the first signalled might create starvation issues.)
|
||
L = list(handles)
|
||
ready = []
|
||
while L:
|
||
res = _winapi.WaitForMultipleObjects(L, False, timeout)
|
||
if res == WAIT_TIMEOUT:
|
||
break
|
||
elif WAIT_OBJECT_0 <= res < WAIT_OBJECT_0 + len(L):
|
||
res -= WAIT_OBJECT_0
|
||
elif WAIT_ABANDONED_0 <= res < WAIT_ABANDONED_0 + len(L):
|
||
res -= WAIT_ABANDONED_0
|
||
else:
|
||
raise RuntimeError('Should not get here')
|
||
ready.append(L[res])
|
||
L = L[res+1:]
|
||
timeout = 0
|
||
return ready
|
||
|
||
_ready_errors = {_winapi.ERROR_BROKEN_PIPE, _winapi.ERROR_NETNAME_DELETED}
|
||
|
||
def wait(object_list, timeout=None):
|
||
'''
|
||
Wait till an object in object_list is ready/readable.
|
||
|
||
Returns list of those objects in object_list which are ready/readable.
|
||
'''
|
||
if timeout is None:
|
||
timeout = INFINITE
|
||
elif timeout < 0:
|
||
timeout = 0
|
||
else:
|
||
timeout = int(timeout * 1000 + 0.5)
|
||
|
||
object_list = list(object_list)
|
||
waithandle_to_obj = {}
|
||
ov_list = []
|
||
ready_objects = set()
|
||
ready_handles = set()
|
||
|
||
try:
|
||
for o in object_list:
|
||
try:
|
||
fileno = getattr(o, 'fileno')
|
||
except AttributeError:
|
||
waithandle_to_obj[o.__index__()] = o
|
||
else:
|
||
# start an overlapped read of length zero
|
||
try:
|
||
ov, err = _winapi.ReadFile(fileno(), 0, True)
|
||
except OSError as e:
|
||
ov, err = None, e.winerror
|
||
if err not in _ready_errors:
|
||
raise
|
||
if err == _winapi.ERROR_IO_PENDING:
|
||
ov_list.append(ov)
|
||
waithandle_to_obj[ov.event] = o
|
||
else:
|
||
# If o.fileno() is an overlapped pipe handle and
|
||
# err == 0 then there is a zero length message
|
||
# in the pipe, but it HAS NOT been consumed...
|
||
if ov and sys.getwindowsversion()[:2] >= (6, 2):
|
||
# ... except on Windows 8 and later, where
|
||
# the message HAS been consumed.
|
||
try:
|
||
_, err = ov.GetOverlappedResult(False)
|
||
except OSError as e:
|
||
err = e.winerror
|
||
if not err and hasattr(o, '_got_empty_message'):
|
||
o._got_empty_message = True
|
||
ready_objects.add(o)
|
||
timeout = 0
|
||
|
||
ready_handles = _exhaustive_wait(waithandle_to_obj.keys(), timeout)
|
||
finally:
|
||
# request that overlapped reads stop
|
||
for ov in ov_list:
|
||
ov.cancel()
|
||
|
||
# wait for all overlapped reads to stop
|
||
for ov in ov_list:
|
||
try:
|
||
_, err = ov.GetOverlappedResult(True)
|
||
except OSError as e:
|
||
err = e.winerror
|
||
if err not in _ready_errors:
|
||
raise
|
||
if err != _winapi.ERROR_OPERATION_ABORTED:
|
||
o = waithandle_to_obj[ov.event]
|
||
ready_objects.add(o)
|
||
if err == 0:
|
||
# If o.fileno() is an overlapped pipe handle then
|
||
# a zero length message HAS been consumed.
|
||
if hasattr(o, '_got_empty_message'):
|
||
o._got_empty_message = True
|
||
|
||
ready_objects.update(waithandle_to_obj[h] for h in ready_handles)
|
||
return [o for o in object_list if o in ready_objects]
|
||
|
||
else:
|
||
|
||
import selectors
|
||
|
||
# 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'):
|
||
_WaitSelector = selectors.PollSelector
|
||
else:
|
||
_WaitSelector = selectors.SelectSelector
|
||
|
||
def wait(object_list, timeout=None):
|
||
'''
|
||
Wait till an object in object_list is ready/readable.
|
||
|
||
Returns list of those objects in object_list which are ready/readable.
|
||
'''
|
||
with _WaitSelector() as selector:
|
||
for obj in object_list:
|
||
selector.register(obj, selectors.EVENT_READ)
|
||
|
||
if timeout is not None:
|
||
deadline = time.time() + timeout
|
||
|
||
while True:
|
||
ready = selector.select(timeout)
|
||
if ready:
|
||
return [key.fileobj for (key, events) in ready]
|
||
else:
|
||
if timeout is not None:
|
||
timeout = deadline - time.time()
|
||
if timeout < 0:
|
||
return ready
|
||
|
||
#
|
||
# Make connection and socket objects sharable if possible
|
||
#
|
||
|
||
if sys.platform == 'win32':
|
||
def reduce_connection(conn):
|
||
handle = conn.fileno()
|
||
with socket.fromfd(handle, socket.AF_INET, socket.SOCK_STREAM) as s:
|
||
from . import resource_sharer
|
||
ds = resource_sharer.DupSocket(s)
|
||
return rebuild_connection, (ds, conn.readable, conn.writable)
|
||
def rebuild_connection(ds, readable, writable):
|
||
sock = ds.detach()
|
||
return Connection(sock.detach(), readable, writable)
|
||
reduction.register(Connection, reduce_connection)
|
||
|
||
def reduce_pipe_connection(conn):
|
||
access = ((_winapi.FILE_GENERIC_READ if conn.readable else 0) |
|
||
(_winapi.FILE_GENERIC_WRITE if conn.writable else 0))
|
||
dh = reduction.DupHandle(conn.fileno(), access)
|
||
return rebuild_pipe_connection, (dh, conn.readable, conn.writable)
|
||
def rebuild_pipe_connection(dh, readable, writable):
|
||
handle = dh.detach()
|
||
return PipeConnection(handle, readable, writable)
|
||
reduction.register(PipeConnection, reduce_pipe_connection)
|
||
|
||
else:
|
||
def reduce_connection(conn):
|
||
df = reduction.DupFd(conn.fileno())
|
||
return rebuild_connection, (df, conn.readable, conn.writable)
|
||
def rebuild_connection(df, readable, writable):
|
||
fd = df.detach()
|
||
return Connection(fd, readable, writable)
|
||
reduction.register(Connection, reduce_connection)
|