freeipa/ipapython/ipasslfile.py

186 lines
5.1 KiB
Python

# This is a forward backport of the Python2.5 uuid module. It isn't available
# in Python 2.6
# The next several classes are used to define FakeSocket, a socket-like
# interface to an SSL connection.
# The primary complexity comes from faking a makefile() method. The
# standard socket makefile() implementation calls dup() on the socket
# file descriptor. As a consequence, clients can call close() on the
# parent socket and its makefile children in any order. The underlying
# socket isn't closed until they are all closed.
# The implementation uses reference counting to keep the socket open
# until the last client calls close(). SharedSocket keeps track of
# the reference counting and SharedSocketClient provides an constructor
# and close() method that call incref() and decref() correctly.
import socket
import errno
from httplib import UnimplementedFileMode, HTTPException
error = HTTPException
class SharedSocket:
def __init__(self, sock):
self.sock = sock
self._refcnt = 0
def incref(self):
self._refcnt += 1
def decref(self):
self._refcnt -= 1
assert self._refcnt >= 0
if self._refcnt == 0:
self.sock.close()
def __del__(self):
self.sock.close()
class SharedSocketClient:
def __init__(self, shared):
self._closed = 0
self._shared = shared
self._shared.incref()
self._sock = shared.sock
def close(self):
if not self._closed:
self._shared.decref()
self._closed = 1
self._shared = None
class SSLFile(SharedSocketClient):
"""File-like object wrapping an SSL socket."""
BUFSIZE = 8192
def __init__(self, sock, ssl, bufsize=None):
SharedSocketClient.__init__(self, sock)
self._ssl = ssl
self._buf = ''
self._bufsize = bufsize or self.__class__.BUFSIZE
def _read(self):
buf = ''
# put in a loop so that we retry on transient errors
while True:
try:
buf = self._ssl.read(self._bufsize)
except socket.sslerror, err:
if (err[0] == socket.SSL_ERROR_WANT_READ
or err[0] == socket.SSL_ERROR_WANT_WRITE):
continue
if (err[0] == socket.SSL_ERROR_ZERO_RETURN
or err[0] == socket.SSL_ERROR_EOF):
break
raise
except socket.error, err:
if err[0] == errno.EINTR:
continue
if err[0] == errno.EBADF:
# XXX socket was closed?
break
raise
else:
break
return buf
def read(self, size=None):
L = [self._buf]
avail = len(self._buf)
while size is None or avail < size:
s = self._read()
if s == '':
break
L.append(s)
avail += len(s)
alldata = "".join(L)
if size is None:
self._buf = ''
return alldata
else:
self._buf = alldata[size:]
return alldata[:size]
def readline(self):
L = [self._buf]
self._buf = ''
while 1:
i = L[-1].find("\n")
if i >= 0:
break
s = self._read()
if s == '':
break
L.append(s)
if i == -1:
# loop exited because there is no more data
return "".join(L)
else:
alldata = "".join(L)
# XXX could do enough bookkeeping not to do a 2nd search
i = alldata.find("\n") + 1
line = alldata[:i]
self._buf = alldata[i:]
return line
def readlines(self, sizehint=0):
total = 0
inlist = []
while True:
line = self.readline()
if not line:
break
inlist.append(line)
total += len(line)
if sizehint and total >= sizehint:
break
return inlist
def fileno(self):
return self._sock.fileno()
def __iter__(self):
return self
def next(self):
line = self.readline()
if not line:
raise StopIteration
return line
class FakeSocket(SharedSocketClient):
class _closedsocket:
def __getattr__(self, name):
raise error(9, 'Bad file descriptor')
def __init__(self, sock, ssl):
sock = SharedSocket(sock)
SharedSocketClient.__init__(self, sock)
self._ssl = ssl
def close(self):
SharedSocketClient.close(self)
self._sock = self.__class__._closedsocket()
def makefile(self, mode, bufsize=None):
if mode != 'r' and mode != 'rb':
raise UnimplementedFileMode()
return SSLFile(self._shared, self._ssl, bufsize)
def send(self, stuff, flags = 0):
return self._ssl.write(stuff)
sendall = send
def recv(self, len = 1024, flags = 0):
return self._ssl.read(len)
def __getattr__(self, attr):
return getattr(self._sock, attr)