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|
# Wrapper module for _ssl, providing some additional facilities
# implemented in Python. Written by Bill Janssen.
raise ImportError("ssl.py is temporarily out of order")
"""\
This module provides some more Pythonic support for SSL.
Object types:
sslsocket -- subtype of socket.socket which does SSL over the socket
Exceptions:
sslerror -- exception raised for I/O errors
Functions:
cert_time_to_seconds -- convert time string used for certificate
notBefore and notAfter functions to integer
seconds past the Epoch (the time values
returned from time.time())
fetch_server_certificate (HOST, PORT) -- fetch the certificate provided
by the server running on HOST at port PORT. No
validation of the certificate is performed.
Integer constants:
SSL_ERROR_ZERO_RETURN
SSL_ERROR_WANT_READ
SSL_ERROR_WANT_WRITE
SSL_ERROR_WANT_X509_LOOKUP
SSL_ERROR_SYSCALL
SSL_ERROR_SSL
SSL_ERROR_WANT_CONNECT
SSL_ERROR_EOF
SSL_ERROR_INVALID_ERROR_CODE
The following group define certificate requirements that one side is
allowing/requiring from the other side:
CERT_NONE - no certificates from the other side are required (or will
be looked at if provided)
CERT_OPTIONAL - certificates are not required, but if provided will be
validated, and if validation fails, the connection will
also fail
CERT_REQUIRED - certificates are required, and will be validated, and
if validation fails, the connection will also fail
The following constants identify various SSL protocol variants:
PROTOCOL_SSLv2
PROTOCOL_SSLv3
PROTOCOL_SSLv23
PROTOCOL_TLSv1
"""
import os, sys
import _ssl # if we can't import it, let the error propagate
from _ssl import sslerror
from _ssl import CERT_NONE, CERT_OPTIONAL, CERT_REQUIRED
from _ssl import PROTOCOL_SSLv2, PROTOCOL_SSLv3, PROTOCOL_SSLv23, PROTOCOL_TLSv1
from _ssl import \
SSL_ERROR_ZERO_RETURN, \
SSL_ERROR_WANT_READ, \
SSL_ERROR_WANT_WRITE, \
SSL_ERROR_WANT_X509_LOOKUP, \
SSL_ERROR_SYSCALL, \
SSL_ERROR_SSL, \
SSL_ERROR_WANT_CONNECT, \
SSL_ERROR_EOF, \
SSL_ERROR_INVALID_ERROR_CODE
from socket import socket
from socket import getnameinfo as _getnameinfo
class sslsocket (socket):
"""This class implements a subtype of socket.socket that wraps
the underlying OS socket in an SSL context when necessary, and
provides read and write methods over that channel."""
def __init__(self, sock, keyfile=None, certfile=None,
server_side=False, cert_reqs=CERT_NONE,
ssl_version=PROTOCOL_SSLv23, ca_certs=None):
socket.__init__(self, _sock=sock._sock)
if certfile and not keyfile:
keyfile = certfile
# see if it's connected
try:
socket.getpeername(self)
except:
# no, no connection yet
self._sslobj = None
else:
# yes, create the SSL object
self._sslobj = _ssl.sslwrap(self._sock, server_side,
keyfile, certfile,
cert_reqs, ssl_version, ca_certs)
self.keyfile = keyfile
self.certfile = certfile
self.cert_reqs = cert_reqs
self.ssl_version = ssl_version
self.ca_certs = ca_certs
def read(self, len=1024):
"""Read up to LEN bytes and return them.
Return zero-length string on EOF."""
return self._sslobj.read(len)
def write(self, data):
"""Write DATA to the underlying SSL channel. Returns
number of bytes of DATA actually transmitted."""
return self._sslobj.write(data)
def getpeercert(self):
"""Returns a formatted version of the data in the
certificate provided by the other end of the SSL channel.
Return None if no certificate was provided, {} if a
certificate was provided, but not validated."""
return self._sslobj.peer_certificate()
def send (self, data, flags=0):
if self._sslobj:
if flags != 0:
raise ValueError(
"non-zero flags not allowed in calls to send() on %s" %
self.__class__)
return self._sslobj.write(data)
else:
return socket.send(self, data, flags)
def send_to (self, data, addr, flags=0):
if self._sslobj:
raise ValueError("send_to not allowed on instances of %s" %
self.__class__)
else:
return socket.send_to(self, data, addr, flags)
def sendall (self, data, flags=0):
if self._sslobj:
if flags != 0:
raise ValueError(
"non-zero flags not allowed in calls to sendall() on %s" %
self.__class__)
return self._sslobj.write(data)
else:
return socket.sendall(self, data, flags)
def recv (self, buflen=1024, flags=0):
if self._sslobj:
if flags != 0:
raise ValueError(
"non-zero flags not allowed in calls to sendall() on %s" %
self.__class__)
return self._sslobj.read(data, buflen)
else:
return socket.recv(self, buflen, flags)
def recv_from (self, addr, buflen=1024, flags=0):
if self._sslobj:
raise ValueError("recv_from not allowed on instances of %s" %
self.__class__)
else:
return socket.recv_from(self, addr, buflen, flags)
def ssl_shutdown(self):
"""Shuts down the SSL channel over this socket (if active),
without closing the socket connection."""
if self._sslobj:
self._sslobj.shutdown()
self._sslobj = None
def shutdown(self, how):
self.ssl_shutdown()
socket.shutdown(self, how)
def close(self):
self.ssl_shutdown()
socket.close(self)
def connect(self, addr):
"""Connects to remote ADDR, and then wraps the connection in
an SSL channel."""
# Here we assume that the socket is client-side, and not
# connected at the time of the call. We connect it, then wrap it.
if self._sslobj:
raise ValueError("attempt to connect already-connected sslsocket!")
socket.connect(self, addr)
self._sslobj = _ssl.sslwrap(self._sock, False, self.keyfile, self.certfile,
self.cert_reqs, self.ssl_version,
self.ca_certs)
def accept(self):
"""Accepts a new connection from a remote client, and returns
a tuple containing that new connection wrapped with a server-side
SSL channel, and the address of the remote client."""
newsock, addr = socket.accept(self)
return (sslsocket(newsock, True, self.keyfile, self.certfile,
self.cert_reqs, self.ssl_version,
self.ca_certs), addr)
# some utility functions
def cert_time_to_seconds(cert_time):
"""Takes a date-time string in standard ASN1_print form
("MON DAY 24HOUR:MINUTE:SEC YEAR TIMEZONE") and return
a Python time value in seconds past the epoch."""
import time
return time.mktime(time.strptime(cert_time, "%b %d %H:%M:%S %Y GMT"))
# a replacement for the old socket.ssl function
def sslwrap_simple (sock, keyfile=None, certfile=None):
"""A replacement for the old socket.ssl function. Designed
for compability with Python 2.5 and earlier. Will disappear in
Python 3.0."""
return _ssl.sslwrap(sock._sock, 0, keyfile, certfile, CERT_NONE,
PROTOCOL_SSLv23, None)
|
