%PDF- %PDF-
Direktori : /proc/thread-self/root/proc/self/root/proc/self/root/lib/python3.6/site-packages/rhn/ |
Current File : //proc/thread-self/root/proc/self/root/proc/self/root/lib/python3.6/site-packages/rhn/SSL.py |
# # Higher-level SSL objects used by rpclib # # Copyright (c) 2002--2017 Red Hat, Inc. # # Author: Mihai Ibanescu <misa@redhat.com> # # In addition, as a special exception, the copyright holders give # permission to link the code of portions of this program with the # OpenSSL library under certain conditions as described in each # individual source file, and distribute linked combinations # including the two. # You must obey the GNU General Public License in all respects # for all of the code used other than OpenSSL. If you modify # file(s) with this exception, you may extend this exception to your # version of the file(s), but you are not obligated to do so. If you # do not wish to do so, delete this exception statement from your # version. If you delete this exception statement from all source # files in the program, then also delete it here. """ rhn.SSL builds an abstraction on top of the objects provided by pyOpenSSL """ from OpenSSL import SSL # SSL.crypto is provided to other modules from OpenSSL import crypto import os import socket import select from rhn.i18n import bstr import sys DEFAULT_TIMEOUT = 120 if hasattr(socket, 'sslerror'): socket_error = socket.sslerror else: from ssl import socket_error class SSLSocket: """ Class that wraps a pyOpenSSL Connection object, adding more methods """ def __init__(self, socket, trusted_certs=None): # SSL.Context object self._ctx = None # SSL.Connection object self._connection = None self._sock = socket self._trusted_certs = [] # convert None to empty list trusted_certs = trusted_certs or [] for f in trusted_certs: self.add_trusted_cert(f) # SSL method to use self._ssl_method = SSL.SSLv23_METHOD # Flags to pass to the SSL layer self._ssl_verify_flags = SSL.VERIFY_PEER # Buffer size for reads self._buffer_size = 8192 # Position, for tell() self._pos = 0 # Buffer self._buffer = bstr("") # Flag to show if makefile() was called self._makefile_called = 0 self._closed = None def add_trusted_cert(self, file): """ Adds a trusted certificate to the certificate store of the SSL context object. """ if not os.access(file, os.R_OK): raise ValueError("Unable to read certificate file %s" % file) self._trusted_certs.append(file.encode("utf-8")) def init_ssl(self): """ Initializes the SSL connection. """ self._check_closed() # Get a context self._ctx = SSL.Context(self._ssl_method) self._ctx.set_options(SSL.OP_NO_SSLv2) self._ctx.set_options(SSL.OP_NO_SSLv3) if self._trusted_certs: # We have been supplied with trusted CA certs for f in self._trusted_certs: self._ctx.load_verify_locations(f) else: # Reset the verify flags self._ssl_verify_flags = 0 self._ctx.set_verify(self._ssl_verify_flags, ssl_verify_callback) if hasattr(SSL, "OP_DONT_INSERT_EMPTY_FRAGMENTS"): # Certain SSL implementations break when empty fragments are # initially sent (even if sending them is compliant to # SSL 3.0 and TLS 1.0 specs). Play it safe and disable this # feature (openssl 0.9.6e and later) self._ctx.set_options(SSL.OP_DONT_INSERT_EMPTY_FRAGMENTS) # Init the connection self._connection = SSL.Connection(self._ctx, self._sock) # Place the connection in client mode self._connection.set_connect_state() def makefile(self, mode, bufsize=None): """ Returns self, since we are a file-like object already """ if bufsize: self._buffer_size = bufsize # Increment the counter with the number of times we've called makefile # - we don't want close to actually close things until all the objects # that originally called makefile() are gone self._makefile_called = self._makefile_called + 1 return self def close(self): """ Closes the SSL connection """ # XXX Normally sock.makefile does a dup() on the socket file # descriptor; httplib relies on this, but there is no dup for an ssl # connection; so we have to count how may times makefile() was called if self._closed: # Nothing to do return if not self._makefile_called: self._really_close() return self._makefile_called = self._makefile_called - 1 # BZ 1464157 - Python 3 http attempts to call this method during close, # at least add it empty def flush(self): pass def _really_close(self): # No connection was established if self._connection is None: return get_state = None try: get_state = getattr(self._connection, 'state_string') except AttributeError: get_state = getattr(self._connection, 'get_state_string') if get_state is not None: # for Python 3 if sys.version_info[0] == 3: if get_state() == b'SSL negotiation finished successfully': self._connection.shutdown() # for Python 2 else: if get_state() == 'SSL negotiation finished successfully': self._connection.shutdown() self._connection.close() self._closed = 1 def _check_closed(self): if self._closed: raise ValueError("I/O operation on closed file") def __getattr__(self, name): if hasattr(self._connection, name): return getattr(self._connection, name) raise AttributeError(name) # File methods def isatty(self): """ Returns false always. """ return 0 def tell(self): return self._pos def seek(self, pos, mode=0): raise NotImplementedError("seek") def read(self, amt=None): """ Reads up to amt bytes from the SSL connection. """ self._check_closed() # Initially, the buffer size is the default buffer size. # Unfortunately, pending() does not return meaningful data until # recv() is called, so we only adjust the buffer size after the # first read buffer_size = self._buffer_size buffer_length = len(self._buffer) # Read only the specified amount of data while buffer_length < amt or amt is None: # if amt is None (read till the end), fills in self._buffer if amt is not None: buffer_size = min(amt - buffer_length, buffer_size) try: data = self._connection.recv(buffer_size) self._buffer = self._buffer + data buffer_length = len(self._buffer) # More bytes to read? pending = self._connection.pending() if pending == 0: # we're done here break except SSL.ZeroReturnError: # Nothing more to be read break except SSL.SysCallError: e = sys.exc_info()[1] print("SSL exception", e.args) break except SSL.WantWriteError: self._poll(select.POLLOUT, 'read') except SSL.WantReadError: self._poll(select.POLLIN, 'read') if amt: ret = self._buffer[:amt] self._buffer = self._buffer[amt:] else: ret = self._buffer self._buffer = bstr("") self._pos = self._pos + len(ret) return ret def readinto(self, buf): buf[:] = self.read(len(buf)) return len(buf) def _poll(self, filter_type, caller_name): poller = select.poll() poller.register(self._sock, filter_type) res = poller.poll(self._sock.gettimeout() * 1000) if res == []: raise TimeoutException("Connection timed out on %s" % caller_name) def write(self, data): """ Writes to the SSL connection. """ self._check_closed() # XXX Should use sendall # sent = self._connection.sendall(data) origlen = len(data) while True: try: sent = self._connection.send(data) if sent == len(data): break data = data[sent:] except SSL.WantWriteError: self._poll(select.POLLOUT, 'write') except SSL.WantReadError: self._poll(select.POLLIN, 'write') return origlen def recv(self, amt): return self.read(amt) send = write sendall = write def readline(self, length=None): """ Reads a single line (up to `length' characters long) from the SSL connection. """ self._check_closed() while True: # charcount contains the number of chars to be outputted (or None # if none to be outputted at this time) charcount = None i = self._buffer.find(bstr('\n')) if i >= 0: # Go one char past newline charcount = i + 1 elif length and len(self._buffer) >= length: charcount = length if charcount is not None: ret = self._buffer[:charcount] self._buffer = self._buffer[charcount:] self._pos = self._pos + len(ret) return ret # Determine the number of chars to be read next bufsize = self._buffer_size if length: # we know length > len(self._buffer) bufsize = min(self._buffer_size, length - len(self._buffer)) try: data = self._connection.recv(bufsize) self._buffer = self._buffer + data except SSL.ZeroReturnError: # Nothing more to be read break except SSL.WantWriteError: self._poll(select.POLLOUT, 'readline') except SSL.WantReadError: self._poll(select.POLLIN, 'readline') # We got here if we're done reading, so return everything ret = self._buffer self._buffer = "" self._pos = self._pos + len(ret) return ret def ssl_verify_callback(conn, cert, errnum, depth, ok): """ Verify callback, which will be called for each certificate in the certificate chain. """ # Nothing by default return ok class TimeoutException(SSL.Error, socket.timeout): def __init__(self, *args): self.args = args def __str__(self): return "Timeout Exception"