Source Code for Module ndg.httpsclient.https

  1  """ndg_httpsclient HTTPS module containing PyOpenSSL implementation of 
  2  httplib.HTTPSConnection 
  3   
  4  PyOpenSSL utility to make a httplib-like interface suitable for use with  
  5  urllib2 
  6  """ 
  7  __author__ = "P J Kershaw (STFC)" 
  8  __date__ = "09/12/11" 
  9  __copyright__ = "(C) 2012 Science and Technology Facilities Council" 
 10  __license__ = "BSD - see LICENSE file in top-level directory" 
 11  __contact__ = "Philip.Kershaw@stfc.ac.uk" 
 12  __revision__ = '$Id$' 
 13  import logging 
 14  import socket 
 15  from httplib import HTTPS_PORT 
 16  from httplib import HTTPConnection 
 17  from urllib2 import AbstractHTTPHandler 
 18   
 19   
 20  from OpenSSL import SSL 
 21   
 22  from ndg.httpsclient.ssl_socket import SSLSocket 
 23   
 24  log = logging.getLogger(__name__) 
 25   
 26   
 27 -class HTTPSConnection(HTTPConnection): 
 28      """This class allows communication via SSL using PyOpenSSL. 
 29      It is based on httplib.HTTPSConnection, modified to use PyOpenSSL. 
 30   
 31      Note: This uses the constructor inherited from HTTPConnection to allow it to 
 32      be used with httplib and HTTPSContextHandler. To use the class directly with 
 33      an SSL context set ssl_context after construction. 
 34       
 35      @cvar default_port: default port for this class (443) 
 36      @type default_port: int 
 37      @cvar default_ssl_method: default SSL method used if no SSL context is 
 38      explicitly set - defaults to version 2/3. 
 39      @type default_ssl_method: int 
 40      """ 
 41      default_port = HTTPS_PORT 
 42      default_ssl_method = SSL.SSLv23_METHOD 
 43       
 44 -    def __init__(self, host, port=None, strict=None, 
 45                   timeout=socket._GLOBAL_DEFAULT_TIMEOUT, ssl_context=None): 
 46          HTTPConnection.__init__(self, host, port, strict, timeout) 
 47          if not hasattr(self, 'ssl_context'): 
 48              self.ssl_context = None 
 49   
 50          if ssl_context is not None: 
 51              if not isinstance(ssl_context, SSL.Context): 
 52                  raise TypeError('Expecting OpenSSL.SSL.Context type for "' 
 53                                  'ssl_context" keyword; got %r instead' % 
 54                                  ssl_context) 
 55                   
 56              self.ssl_context = ssl_context 
 57               
 58 -    def connect(self): 
 59          """Create SSL socket and connect to peer 
 60          """ 
 61          if getattr(self, 'ssl_context', None): 
 62              if not isinstance(self.ssl_context, SSL.Context): 
 63                  raise TypeError('Expecting OpenSSL.SSL.Context type for "' 
 64                                  'ssl_context" attribute; got %r instead' % 
 65                                  self.ssl_context) 
 66              ssl_context = self.ssl_context 
 67          else: 
 68              ssl_context = SSL.Context(self.__class__.default_ssl_method) 
 69   
 70          sock = socket.create_connection((self.host, self.port), self.timeout) 
 71           
 72          # Tunnel if using a proxy - ONLY available for Python 2.6.2 and above       
 73          if getattr(self, '_tunnel_host', None): 
 74              self.sock = sock 
 75              self._tunnel() 
 76               
 77          self.sock = SSLSocket(ssl_context, sock) 
 78           
 79          # Go to client mode. 
 80          self.sock.set_connect_state() 
 81   
 82 -    def close(self): 
 83          """Close socket and shut down SSL connection""" 
 84          self.sock.close() 
 85           
 86           
 87 -class HTTPSContextHandler(AbstractHTTPHandler): 
 88      '''HTTPS handler that allows a SSL context to be set for the SSL 
 89      connections. 
 90      ''' 
 91      https_request = AbstractHTTPHandler.do_request_ 
 92   
 93 -    def __init__(self, ssl_context, debuglevel=0): 
 94          """ 
 95          @param ssl_context:SSL context 
 96          @type ssl_context: OpenSSL.SSL.Context 
 97          @param debuglevel: debug level for HTTPSHandler 
 98          @type debuglevel: int 
 99          """ 
100          AbstractHTTPHandler.__init__(self, debuglevel) 
101   
102          if ssl_context is not None: 
103              if not isinstance(ssl_context, SSL.Context): 
104                  raise TypeError('Expecting OpenSSL.SSL.Context type for "' 
105                                  'ssl_context" keyword; got %r instead' % 
106                                  ssl_context) 
107              self.ssl_context = ssl_context 
108          else: 
109              self.ssl_context = SSL.Context(SSL.SSLv23_METHOD) 
110   
111 -    def https_open(self, req): 
112          """Opens HTTPS request 
113          @param req: HTTP request 
114          @return: HTTP Response object 
115          """ 
116          # Make a custom class extending HTTPSConnection, with the SSL context 
117          # set as a class variable so that it is available to the connect method. 
118          customHTTPSContextConnection = type('CustomHTTPSContextConnection', 
119                                              (HTTPSConnection, object), 
120                                              {'ssl_context': self.ssl_context}) 
121          return self.do_open(customHTTPSContextConnection, req) 
122