+##
+# This module implements a general-purpose server layer for sfa.
+# The same basic server should be usable on the registry, component, or
+# other interfaces.
+#
+# TODO: investigate ways to combine this with existing PLC server?
+##
+
+import sys
+import socket
+import traceback
+import threading
+from Queue import Queue
+import SocketServer
+import BaseHTTPServer
+import SimpleXMLRPCServer
+from OpenSSL import SSL
+
+from sfa.util.sfalogging import logger
+from sfa.util.config import Config
+from sfa.util.cache import Cache
+from sfa.trust.certificate import Certificate
+from sfa.trust.trustedroots import TrustedRoots
+#seems useless
+#from sfa.trust.credential import *
+#can we get rid of that ?
+from sfa.plc.api import SfaAPI
+
+##
+# Verification callback for pyOpenSSL. We do our own checking of keys because
+# we have our own authentication spec. Thus we disable several of the normal
+# prohibitions that OpenSSL places on certificates
+
+def verify_callback(conn, x509, err, depth, preverify):
+ # if the cert has been preverified, then it is ok
+ if preverify:
+ #print " preverified"
+ return 1
+
+
+ # the certificate verification done by openssl checks a number of things
+ # that we aren't interested in, so we look out for those error messages
+ # and ignore them
+
+ # XXX SMBAKER: I don't know what this error is, but it's being returned
+ # by newer pl nodes.
+ if err == 9:
+ #print " X509_V_ERR_CERT_NOT_YET_VALID"
+ return 1
+
+ # allow self-signed certificates
+ if err == 18:
+ #print " X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT"
+ return 1
+
+ # allow certs that don't have an issuer
+ if err == 20:
+ #print " X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY"
+ return 1
+
+ # allow chained certs with self-signed roots
+ if err == 19:
+ return 1
+
+ # allow certs that are untrusted
+ if err == 21:
+ #print " X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE"
+ return 1
+
+ # allow certs that are untrusted
+ if err == 27:
+ #print " X509_V_ERR_CERT_UNTRUSTED"
+ return 1
+
+ print " error", err, "in verify_callback"
+
+ return 0
+
+##
+# taken from the web (XXX find reference). Implements HTTPS xmlrpc request handler
+class SecureXMLRpcRequestHandler(SimpleXMLRPCServer.SimpleXMLRPCRequestHandler):
+ """Secure XML-RPC request handler class.
+
+ It it very similar to SimpleXMLRPCRequestHandler but it uses HTTPS for transporting XML data.
+ """
+ def setup(self):
+ self.connection = self.request
+ self.rfile = socket._fileobject(self.request, "rb", self.rbufsize)
+ self.wfile = socket._fileobject(self.request, "wb", self.wbufsize)
+
+ def do_POST(self):
+ """Handles the HTTPS POST request.
+
+ It was copied out from SimpleXMLRPCServer.py and modified to shutdown
+ the socket cleanly.
+ """
+ try:
+ peer_cert = Certificate()
+ peer_cert.load_from_pyopenssl_x509(self.connection.get_peer_certificate())
+ self.api = SfaAPI(peer_cert = peer_cert,
+ interface = self.server.interface,
+ key_file = self.server.key_file,
+ cert_file = self.server.cert_file,
+ cache = self.cache)
+ # get arguments
+ request = self.rfile.read(int(self.headers["content-length"]))
+ remote_addr = (remote_ip, remote_port) = self.connection.getpeername()
+ self.api.remote_addr = remote_addr
+ response = self.api.handle(remote_addr, request, self.server.method_map)
+ except Exception, fault:
+ # This should only happen if the module is buggy
+ # internal error, report as HTTP server error
+ logger.log_exc("server.do_POST")
+ response = self.api.prepare_response(fault)
+ #self.send_response(500)
+ #self.end_headers()
+
+ # got a valid response
+ self.send_response(200)
+ self.send_header("Content-type", "text/xml")
+ self.send_header("Content-length", str(len(response)))
+ self.end_headers()
+ self.wfile.write(response)
+
+ # shut down the connection
+ self.wfile.flush()
+ self.connection.shutdown() # Modified here!
+
+##
+# Taken from the web (XXX find reference). Implements an HTTPS xmlrpc server
+class SecureXMLRPCServer(BaseHTTPServer.HTTPServer,SimpleXMLRPCServer.SimpleXMLRPCDispatcher):
+ def __init__(self, server_address, HandlerClass, key_file, cert_file, logRequests=True):
+ """Secure XML-RPC server.
+
+ It it very similar to SimpleXMLRPCServer but it uses HTTPS for transporting XML data.
+ """
+ logger.debug("SecureXMLRPCServer.__init__, server_address=%s, cert_file=%s"%(server_address,cert_file))
+ self.logRequests = logRequests
+ self.interface = None
+ self.key_file = key_file
+ self.cert_file = cert_file
+ self.method_map = {}
+ # add cache to the request handler
+ HandlerClass.cache = Cache()
+ #for compatibility with python 2.4 (centos53)
+ if sys.version_info < (2, 5):
+ SimpleXMLRPCServer.SimpleXMLRPCDispatcher.__init__(self)
+ else:
+ SimpleXMLRPCServer.SimpleXMLRPCDispatcher.__init__(self, True, None)
+ SocketServer.BaseServer.__init__(self, server_address, HandlerClass)
+ ctx = SSL.Context(SSL.SSLv23_METHOD)
+ ctx.use_privatekey_file(key_file)
+ ctx.use_certificate_file(cert_file)
+ # If you wanted to verify certs against known CAs.. this is how you would do it
+ #ctx.load_verify_locations('/etc/sfa/trusted_roots/plc.gpo.gid')
+ config = Config()
+ trusted_cert_files = TrustedRoots(config.get_trustedroots_dir()).get_file_list()
+ for cert_file in trusted_cert_files:
+ ctx.load_verify_locations(cert_file)
+ ctx.set_verify(SSL.VERIFY_PEER | SSL.VERIFY_FAIL_IF_NO_PEER_CERT, verify_callback)
+ ctx.set_verify_depth(5)
+ ctx.set_app_data(self)
+ self.socket = SSL.Connection(ctx, socket.socket(self.address_family,
+ self.socket_type))
+ self.server_bind()
+ self.server_activate()
+
+ # _dispatch
+ #
+ # Convert an exception on the server to a full stack trace and send it to
+ # the client.
+
+ def _dispatch(self, method, params):
+ logger.debug("SecureXMLRPCServer._dispatch, method=%s"%method)
+ try:
+ return SimpleXMLRPCServer.SimpleXMLRPCDispatcher._dispatch(self, method, params)
+ except:
+ # can't use format_exc() as it is not available in jython yet
+ # (even in trunk).
+ type, value, tb = sys.exc_info()
+ raise xmlrpclib.Fault(1,''.join(traceback.format_exception(type, value, tb)))
+
+ # override this one from the python 2.7 code
+ # originally defined in class TCPServer
+ def shutdown_request(self, request):
+ """Called to shutdown and close an individual request."""
+ # ----------
+ # the std python 2.7 code just attempts a request.shutdown(socket.SHUT_WR)
+ # this works fine with regular sockets
+ # However we are dealing with an instance of OpenSSL.SSL.Connection instead
+ # This one only supports shutdown(), and in addition this does not
+ # always perform as expected
+ # ---------- std python 2.7 code
+ try:
+ #explicitly shutdown. socket.close() merely releases
+ #the socket and waits for GC to perform the actual close.
+ request.shutdown(socket.SHUT_WR)
+ except socket.error:
+ pass #some platforms may raise ENOTCONN here
+ # ----------
+ except TypeError:
+ # we are dealing with an OpenSSL.Connection object,
+ # try to shut it down but never mind if that fails
+ try: request.shutdown()
+ except: pass
+ # ----------
+ self.close_request(request)
+
+## From Active State code: http://code.activestate.com/recipes/574454/
+# This is intended as a drop-in replacement for the ThreadingMixIn class in
+# module SocketServer of the standard lib. Instead of spawning a new thread
+# for each request, requests are processed by of pool of reusable threads.
+class ThreadPoolMixIn(SocketServer.ThreadingMixIn):
+ """
+ use a thread pool instead of a new thread on every request
+ """
+ # XX TODO: Make this configurable
+ # config = Config()
+ # numThreads = config.SFA_SERVER_NUM_THREADS
+ numThreads = 25
+ allow_reuse_address = True # seems to fix socket.error on server restart
+
+ def serve_forever(self):
+ """
+ Handle one request at a time until doomsday.
+ """
+ # set up the threadpool
+ self.requests = Queue()
+
+ for x in range(self.numThreads):
+ t = threading.Thread(target = self.process_request_thread)
+ t.setDaemon(1)
+ t.start()
+
+ # server main loop
+ while True:
+ self.handle_request()
+
+ self.server_close()
+
+
+ def process_request_thread(self):
+ """
+ obtain request from queue instead of directly from server socket
+ """
+ while True:
+ SocketServer.ThreadingMixIn.process_request_thread(self, *self.requests.get())
+
+
+ def handle_request(self):
+ """
+ simply collect requests and put them on the queue for the workers.
+ """
+ try:
+ request, client_address = self.get_request()
+ except socket.error:
+ return
+ if self.verify_request(request, client_address):
+ self.requests.put((request, client_address))
+
+class ThreadedServer(ThreadPoolMixIn, SecureXMLRPCServer):
+ pass