cimtest - add SSL support to indication_tester.py - CIM

Monday, 19 March 2012

In the XenKvmLib directory in cimtest, there is a "indication_tester.py"
module that is both a command-line program and a component of cimtest.  Here
is a proposed patch that adds new functionality to the cmdline interface
while preserving compatibility with cimtest.

The most significant new feature is support for SSL indications.  There is
also a new --trigger mode to generate a test indication using the SFCB
Test_Indication provider.  This allows the script to act as a completely
stand-alone test tool (for SFCB) without the user having to rely on the
"xmltest" files and wbemcat.

Below is a complete list of the new features.  I am looking for feedback and
potentially, the correct process to check into "cimtest".

Best regards,
Dave Heller

New features:

- Supports https indications. Adds new options --certFile and --keyFile to
specify server certificate and private key for the SSL enabled indication
listener.
- Supports verification of indication sender (i.e. CIMOM) SSL certificate.
New option --trustStore is used to specify the CA certificate file;
alternately the --noverify option may be used to disable peer certificate
checking. 
- Adds new option --dest to specify handler destination. This same URL is
used to register the subscription (at the CIMOM) and start the indication
listener (locally). Via --dest one can specify scheme (http or https), IP or
hostname, listener port, and optionally userid:password, all in a single
parameter. 
- New option --interop can be used to override the default interop namespace
(i.e root/interop vs. root/PG_InterOp) allowing easy support for both
openpegasus and sfcb.
- Modifies the default value of existing --ns option (indication namespace);
if not specified the indication namespace will default to the same value as
the interop namespace.
- New option --verbose can be used to display debugging info, such as
details (subject, issuer) of the indication sender cert (when peer
verification enabled).
- Improved error handling (i.e. catch exceptions) for the following
operations: starting listener locally, receiving incoming indications, POST
operations (i.e. subscribe, unsubscribe) to CIMOM.
- New option --trigger can be used to send a request to CIMOM to trigger an
indication via the SFCB Test_Indication provider.

Limitations:

- Not tested on IPv6.
- The --trigger option currently only supports the sfcb Test_Indication
provider.  (It could be made more general by allowing the XML send to
support an arbitrary namespace, classname and method call.  Open to
suggestions here.)

--- indication_tester.orig.py	2012-03-05 23:12:08.000000000 -0500
+++ indication_tester.py	2012-03-19 13:12:55.000000000 -0400
@@ -1,18 +1,25 @@
 #!/usr/bin/python
-# Copyright IBM Corp. 2007
+# Copyright IBM Corp. 2007-2012
 #
 # indication_tester.py - Tool for testing indication subscription and
 #                        delivery against a CIMOM
 # Author: Dan Smith <danms(a)us.ibm.com&gt;
+# SSL support added by Dave Heller <hellerda(a)us.ibm.com&gt;
 
 import sys
 from optparse import OptionParser
-import BaseHTTPServer
+from urlparse import urlparse, urlunparse
+from xml.dom.minidom import parse, parseString
 import httplib
 import base64
-from xml.dom.minidom import parse, parseString
+import errno, os, re
+import socket
+from SocketServer import BaseServer
+from SimpleHTTPServer import SimpleHTTPRequestHandler
+from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
+from OpenSSL import SSL
 
-def filter_xml(name, type, ns, sysname):
+def filter_xml(name, type, ns, sysname, interopNS):
     return """
     <?xml version="1.0" encoding="utf-8"?>
     <CIM CIMVERSION="2.0" DTDVERSION="2.0">
@@ -20,8 +27,8 @@
       <SIMPLEREQ>
         <IMETHODCALL NAME="CreateInstance">
           <LOCALNAMESPACEPATH>
-            <NAMESPACE NAME="root"/>
-            <NAMESPACE NAME="PG_InterOp"/>
+            <NAMESPACE NAME="%s"/>
+            <NAMESPACE NAME="%s"/>
           </LOCALNAMESPACEPATH>
           <IPARAMVALUE NAME="NewInstance">
               <INSTANCE CLASSNAME="CIM_IndicationFilter">
@@ -53,9 +60,9 @@
         </SIMPLEREQ>
       </MESSAGE>
     </CIM>
-    """ % (sysname, name, type, ns)
+    """ % (interopNS[0], interopNS[1], sysname, name, type, ns)
 
-def handler_xml(name, port, sysname):
+def handler_xml(name, destUrl, sysname, interopNS):
     return """
     <?xml version="1.0" encoding="utf-8"?>
     <CIM CIMVERSION="2.0" DTDVERSION="2.0">
@@ -63,8 +70,8 @@
         <SIMPLEREQ>
         <IMETHODCALL NAME="CreateInstance">
             <LOCALNAMESPACEPATH>
-              <NAMESPACE NAME="root"/>
-              <NAMESPACE NAME="PG_InterOp"/>
+              <NAMESPACE NAME="%s"/>
+              <NAMESPACE NAME="%s"/>
             </LOCALNAMESPACEPATH>
             <IPARAMVALUE NAME="NewInstance">
               <INSTANCE CLASSNAME="CIM_IndicationHandlerCIMXML">
@@ -81,7 +88,7 @@
                   <VALUE>%sHandler</VALUE>
                 </PROPERTY>
                 <PROPERTY NAME="Destination" TYPE="string">
-                  <VALUE>http://localhost:%i</VALUE>
+                  <VALUE>%s</VALUE>
                 </PROPERTY>
               </INSTANCE>
             </IPARAMVALUE>
@@ -89,9 +96,9 @@
         </SIMPLEREQ>
       </MESSAGE>
       </CIM>
-      """ % (sysname, name, port)
+      """ % (interopNS[0], interopNS[1], sysname, name, destUrl)
 
-def subscription_xml(name, sysname):
+def subscription_xml(name, sysname, interopNS):
     return """
     <?xml version="1.0" encoding="utf-8"?>
     <CIM CIMVERSION="2.0" DTDVERSION="2.0">
@@ -99,8 +106,8 @@
         <SIMPLEREQ>
           <IMETHODCALL NAME="CreateInstance">
             <LOCALNAMESPACEPATH>
-              <NAMESPACE NAME="root"/>
-              <NAMESPACE NAME="PG_InterOp"/>
+              <NAMESPACE NAME="%s"/>
+              <NAMESPACE NAME="%s"/>
             </LOCALNAMESPACEPATH>
             <IPARAMVALUE NAME="NewInstance">
               <INSTANCE CLASSNAME="CIM_IndicationSubscription">
@@ -167,9 +174,9 @@
         </SIMPLEREQ>
       </MESSAGE>
       </CIM>
-      """ % (sysname, name, sysname, name)
+      """ % (interopNS[0], interopNS[1], sysname, name, sysname, name)
 
-def delete_inst_xml(name, type, sysname, inst_name):
+def delete_inst_xml(name, type, sysname, inst_name, interopNS):
     return """
     <?xml version="1.0" encoding="utf-8"?>
     <CIM CIMVERSION="2.0" DTDVERSION="2.0">
@@ -177,8 +184,8 @@
         <SIMPLEREQ>
           <IMETHODCALL NAME="DeleteInstance">
             <LOCALNAMESPACEPATH>
-              <NAMESPACE NAME="root"/>
-              <NAMESPACE NAME="PG_InterOp"/>
+              <NAMESPACE NAME="%s"/>
+              <NAMESPACE NAME="%s"/>
             </LOCALNAMESPACEPATH>
             <IPARAMVALUE NAME="InstanceName">
               <INSTANCENAME CLASSNAME="CIM_Indication%s">
@@ -200,9 +207,9 @@
         </SIMPLEREQ>
       </MESSAGE>
     </CIM>;
-    """ % (type, sysname, type, inst_name);
+    """ % (interopNS[0], interopNS[1], type, sysname, type, inst_name);
 
-def delete_sub_xml(name, sysname):
+def delete_sub_xml(name, sysname, interopNS):
     return """
     <?xml version="1.0" encoding="utf-8"?>
     <CIM CIMVERSION="2.0" DTDVERSION="2.0">
@@ -210,8 +217,8 @@
         <SIMPLEREQ>
           <IMETHODCALL NAME="DeleteInstance">
             <LOCALNAMESPACEPATH>
-              <NAMESPACE NAME="root"/>
-              <NAMESPACE NAME="PG_InterOp"/>
+              <NAMESPACE NAME="%s"/>
+              <NAMESPACE NAME="%s"/>
             </LOCALNAMESPACEPATH>
             <IPARAMVALUE NAME="InstanceName">
               <INSTANCENAME CLASSNAME="CIM_IndicationSubscription">
@@ -273,7 +280,45 @@
         </SIMPLEREQ>
       </MESSAGE>
     </CIM>;
-    """ % (sysname, name, sysname, name)
+    """ % (interopNS[0], interopNS[1], sysname, name, sysname, name)
+
+def trigger_xml(type, interopNS):
+    return """
+    <?xml version="1.0" encoding="utf-8"?>
+    <CIM CIMVERSION="2.0" DTDVERSION="2.0">
+      <MESSAGE ID="4711" PROTOCOLVERSION="1.0">
+        <SIMPLEREQ>
+          <METHODCALL NAME="SendTestIndication">
+            <LOCALCLASSPATH>
+              <LOCALNAMESPACEPATH>
+                <NAMESPACE NAME="%s"/>
+                <NAMESPACE NAME="%s"/>
+              </LOCALNAMESPACEPATH>
+              <CLASSNAME NAME="%s"/>
+            </LOCALCLASSPATH>
+          </METHODCALL>
+        </SIMPLEREQ>
+      </MESSAGE>
+    </CIM>
+    """ % (interopNS[0], interopNS[1], type)
+    # FIXME: this should really use indication NS, not interop NS.
+
+def update_url_port(parsedUrl, port):
+    # Must manually reconstruct netloc to update the port value.
+    if isinstance(parsedUrl.username, basestring):
+      if isinstance(parsedUrl.password, basestring):
+        netloc = "%s:%s@%s:%s" % (parsedUrl.username, parsedUrl.password,
+                                  parsedUrl.hostname, port)
+      else:
+        netloc = "%s@%s:%s" % (parsedUrl.username,
+                               parsedUrl.hostname, port)
+    else:
+      netloc = "%s:%s" % (parsedUrl.hostname, port)
+
+    # Reassemble url with the updated netloc. return a string.
+    return urlunparse((parsedUrl.scheme, netloc,
+                       parsedUrl.path, parsedUrl.params,
+                       parsedUrl.query, parsedUrl.fragment))
 
 class CIMIndication:
     def __init__(self, xmldata):
@@ -286,50 +331,135 @@
     def __str__(self):
         return self.name
 
-class CIMSocketHandler(BaseHTTPServer.BaseHTTPRequestHandler):
+def socket_handler_wrapper(*parms):
+    try:
+        CIMSocketHandler(*parms)
+    except Exception as e:
+        print "SSL error: %s" % str(e)
+
+class CIMSocketHandler(SimpleHTTPRequestHandler):
+    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):
         length = self.headers.getheader('content-length')
         data = self.rfile.read(int(length))
 
         indication = CIMIndication(data)
-        print "Got indication: %s" % indication
+        print "Got indication: %s from %s" % (indication,
self.client_address)
         if self.server.print_ind:
-            print "%s\n\n" % data
+            print "%s\n" % data
         self.server.indications.append(indication)
+        # Silence the unwanted log output from send_response()
+        realStderr = sys.stderr
+        sys.stderr = open(os.devnull,'a')
+        self.send_response(200)
+        sys.stderr = realStderr
+
+class SecureHTTPServer(HTTPServer):
+    def __init__(self, server_address, HandlerClass):
+        BaseServer.__init__(self, server_address, HandlerClass)
+
+        def verify_cb(conn, cert, errnum, depth, ok):
+          if options.verbose:
+            print('Verify peer certificate chain: level %d:' % depth)
+            print('subject=%s' % cert.get_subject())
+            print('issuer =%s' % cert.get_issuer())
+          return ok
+
+        ctx = SSL.Context(SSL.SSLv23_METHOD)
+        #ctx.use_certificate_file(options.certFile)
+        ctx.use_certificate_chain_file(options.certFile)
+        ctx.use_privatekey_file(options.keyFile)
+
+        if options.noverify:
+            ctx.set_verify(SSL.VERIFY_NONE, verify_cb)
+        else:
+            #ctx.set_verify(SSL.VERIFY_PEER, verify_cb)
+            ctx.set_verify(SSL.VERIFY_PEER|SSL.VERIFY_FAIL_IF_NO_PEER_CERT,
+                           verify_cb)
+            ctx.load_verify_locations(options.trustStore)
+
+        self.socket = SSL.Connection(ctx,
socket.socket(self.address_family,
+                                                        self.socket_type))
+        self.server_bind()
+        self.server_activate()
 
+# The param defaults allow new options from main() w/o losing compat w/
cimtest.
 class CIMIndicationSubscription:
-    def __init__(self, name, typ, ns, print_ind, sysname, port=0):
+    def __init__(self, name, typ, ns, print_ind, sysname, port=0,
+            interopNS=('root','PG_InterOp'),
destUrl="http://localhost:8000",
+            triggermode=False):
         self.name = name
         self.type = typ
         self.ns = ns
         self.sysname = sysname
+        self.interopNS = interopNS
+        self.print_ind = print_ind
+
+        # We do not want to open a listener socket in trigger mode.
+        if triggermode:
+          self.trigger_xml = trigger_xml(typ, interopNS)
+          return
+
+        parsedUrl = urlparse(destUrl)
+
+        # Increment the listener port by the offset value.
+        if isinstance(parsedUrl.port, int):
+          listenerPort = parsedUrl.port + port
+        else:
+          listenerPort = 8000 + port
+
+        destUrl = update_url_port(parsedUrl, listenerPort)
+
+        try:
+            if parsedUrl.scheme == "http":
+                self.server = HTTPServer((parsedUrl.hostname,
+                                          listenerPort),
+                                          CIMSocketHandler)
+            elif parsedUrl.scheme == "https":
+                self.server = SecureHTTPServer((parsedUrl.hostname,
+                                                listenerPort),
+                                                socket_handler_wrapper)
+        except IOError as e:
+            print "Error creating listener socket: %s" % str(e)
+            exit(e.errno)
 
-        self.port = 8000 + port
-        self.server = BaseHTTPServer.HTTPServer(('', self.port),
-                                                 CIMSocketHandler)
         self.server.print_ind = print_ind
         self.server.indications = []
 
-        self.filter_xml = filter_xml(name, typ, ns, sysname)
-        self.handler_xml = handler_xml(name, self.port, sysname)
-        self.subscription_xml = subscription_xml(name, sysname)
+        self.filter_xml = filter_xml(name, typ, ns, sysname, interopNS)
+        self.handler_xml = handler_xml(name, destUrl, sysname, interopNS)
+        self.subscription_xml = subscription_xml(name, sysname, interopNS)
 
     def __do_cimpost(self, conn, body, method, auth_hdr=None):
         headers = {"CIMOperation" : "MethodCall",
                    "CIMMethod"    : method,
-                   "CIMObject"    : "root/PG_Interop",
+                  #"CIMObject"    : "root/PG_Interop",
+                   "CIMObject"    : "%s/%s" % self.interopNS,
                    "Content-Type" : 'application/xml;
charset="utf-8"'}
 
         if auth_hdr:
             headers["Authorization"] = "Basic %s" % auth_hdr
 
-        conn.request("POST", "/cimom", body, headers)
-        resp = conn.getresponse()
-        if not resp.getheader("content-length"):
-            raise Exception("Request Failed: %d %s" %
-                            (resp.status, resp.reason))
-
-        resp.read()
+        try:
+            conn.request("POST", "/cimom", body, headers)
+            resp = conn.getresponse()
+            if not resp.getheader("content-length"):
+                raise Exception("Request Failed: %d %s" %
+                                (resp.status, resp.reason))
+        except IOError as e:
+            print "Error connecting to CIMOM: %s" % str(e)
+            exit(e.errno)
+
+        if self.print_ind:
+            print "Reply from CIMOM:"
+            #print resp.msg
+            print resp.read()
+        else:
+            resp.read()
 
     def subscribe(self, url, cred=None):
         self.conn = httplib.HTTPConnection(url)
@@ -353,26 +483,39 @@
         else:
             auth_hdr = None
 
-        xml = delete_sub_xml(self.name, self.sysname)
+        xml = delete_sub_xml(self.name, self.sysname, self.interopNS)
         self.__do_cimpost(self.conn, xml,
                           "DeleteInstance", auth_hdr)
         xml = delete_inst_xml(self.name, "HandlerCIMXML", self.sysname,
-                              "%sHandler" % self.name)
+                              "%sHandler" % self.name, self.interopNS)
         self.__do_cimpost(self.conn, xml,
                           "DeleteInstance", auth_hdr)
         xml = delete_inst_xml(self.name, "Filter", self.sysname,
-                              "%sFilter" % self.name)
+                              "%sFilter" % self.name, self.interopNS)
         self.__do_cimpost(self.conn, xml,
                           "DeleteInstance", auth_hdr)
 
-def dump_xml(name, typ, ns, sysname):
-    filter_str = filter_xml(name, typ, ns, sysname)
-    handler_str = handler_xml(name, 8000, sysname)
-    subscript_str = subscription_xml(name, sysname)
-    del_filter_str = delete_inst_xml(name, "Filter", sysname,
"%sFilter" %
name)
+    def trigger(self, url, cred=None):
+        self.conn = httplib.HTTPConnection(url)
+        if cred:
+            (u, p) = cred
+            auth_hdr = base64.b64encode("%s:%s" % (u, p))
+        else:
+            auth_hdr = None
+
+        self.__do_cimpost(self.conn, self.trigger_xml,
+                          "SendTestIndication", auth_hdr)
+
+def dump_xml(name, typ, ns, sysname, interopNS, destUrl):
+    filter_str = filter_xml(name, typ, ns, sysname, interopNS)
+    handler_str = handler_xml(name, destUrl, sysname, interopNS)
+    subscript_str = subscription_xml(name, sysname, interopNS)
+    del_filter_str = delete_inst_xml(name, "Filter", sysname,
"%sFilter" %
name,
+                                     interopNS)
     del_handler_str = delete_inst_xml(name, "HandlerCIMXML", sysname,
-                                      "%sHandler" % name)
-    del_subscript_str = delete_sub_xml(name, sysname)
+                                      "%sHandler" % name, interopNS)
+    del_subscript_str = delete_sub_xml(name, sysname, interopNS)
+    trigger_str = trigger_xml(typ, interopNS)
 
     print "CreateFilter:\n%s\n" % filter_str
     print "DeleteFilter:\n%s\n" % del_filter_str
@@ -380,15 +523,20 @@
     print "DeleteHandler:\n%s\n" % del_handler_str
     print "CreateSubscription:\n%s\n" % subscript_str
     print "DeleteSubscription:\n%s\n" % del_subscript_str
+    print "Indication trigger:\n%s\n" % trigger_str
 
 def main():
     usage = "usage: %prog [options] provider\nex: %prog
CIM_InstModification"
     parser = OptionParser(usage)
 
+    # FIXME: SecureHTTPServer still relies on this, need a better way.
+    global options
+
     parser.add_option("-u", "--url", dest="url",
default="localhost:5988",
                       help="URL of CIMOM to connect to (host:port)")
-    parser.add_option("-N", "--ns", dest="ns",
default="root/virt",
-                      help="Namespace (default is root/virt)")
+    parser.add_option("-N", "--ns", dest="ns",
+                      help="Namespace in which the register the indication
\
+                      (default is the same value as the interop
namespace)")
     parser.add_option("-n", "--name", dest="name",
default="Test",
                       help="Name for filter, handler, subscription \
                       (default: Test)")
@@ -398,16 +546,41 @@
     parser.add_option("-p", "--print-ind",
dest="print_ind", default=False,
                       action="store_true",
                       help="Print received indications to stdout.")
+    parser.add_option("-v", "--verbose", dest="verbose",
default=False,
+                      action="store_true",
+                      help="Print addtional debug info.")
     parser.add_option("-U", "--user", dest="username",
default=None,
-                      help="HTTP Auth username")
+                      help="HTTP Auth username (CIMOM)")
     parser.add_option("-P", "--pass", dest="password",
default=None,
-                      help="HTTP Auth password")
+                      help="HTTP Auth password (CIMOM)")
     parser.add_option("--port", dest="port", default=0, type=int,
                       help="Port increment value (server default: 8000)")
+    parser.add_option("--dest", dest="destUrl",
default="localhost:8000",
+                      help="URL of destination handler \
+                      (default: http://localhost:8000)")
+    parser.add_option("--certFile", dest="certFile", default=None,
+                      help="File containing the local certificate to use")
+    parser.add_option("--keyFile", dest="keyFile", default=None,
+                      help="File containing private key for local cert \
+                      (if none provided, assume key is in the certFile)")
+    parser.add_option("--trustStore", dest="trustStore",
default=None,
+                      help="File containing trusted certificates for \
+                      remote endpoint verification")
+    parser.add_option("--noverify", dest="noverify", default=False,
+                      action="store_true",
+                      help="Skip verification of remote endpoint
certificate \
+                      for incoming https indications")
+    parser.add_option("-i", "--interop", dest="interop",
+                      default="root/interop",
+                      help="Interop namespace name (default:
root/interop)")
+    parser.add_option("-t", "--trigger", dest="trigger",
default=False,
+                      action="store_true",
+                      help="Trigger mode: send a request to CIMOM to
trigger \
+                      an indication via a method call ")
 
     (options, args) = parser.parse_args()
 
-    if len(args) == 0:
+    if not options.trigger and len(args)==0:
         print "Fatal: no indication type provided."
         sys.exit(1)
 
@@ -421,20 +594,75 @@
     else:
         sysname = options.url
 
+    if "/" in options.interop:
+        options.interopNS = tuple(options.interop.split("/"))
+    else:
+        options.interopNS = ("root", options.interop)
+
+    # If no value provided for indication NS, default is same as interopNS.
+    if not options.ns:
+        options.ns = "%s/%s" % options.interopNS
+
+    if options.verbose:
+        print "Interop namespace = %s/%s" % options.interopNS
+        print "Indication namespace = %s" % options.ns
+
+    # If url does not begin with http or https, assume http.
+    parsedUrl = urlparse(options.destUrl)
+    if not re.search(parsedUrl.scheme, "https"):
+        destUrl = "http://" + options.destUrl
+    else:
+        destUrl = options.destUrl
+
+    if parsedUrl.scheme == "https":
+        if not options.trustStore and not options.noverify:
+            print "Error: must provide --trustStore or --noverify with
https."
+            sys.exit(1)
+        elif options.trustStore and options.noverify:
+            print "Error: options --trustStore and --noverify are
exclusive."
+            sys.exit(1)
+        if not options.certFile:
+            print "Error: no certificate file provided."
+            sys.exit(1)
+        elif not options.keyFile:
+            print "No keyFile provided; assuming private key \
+            contained in certFile."
+            options.keyFile = options.certFile
+
     if options.dump:
-        dump_xml(options.name, args[0], options.ns, sysname)
+        if isinstance(parsedUrl.port, int):
+          listenerPort = parsedUrl.port + options.port
+        else:
+          listenerPort = 8000 + options.port
+
+        destUrl = update_url_port(parsedUrl, listenerPort)
+        dump_xml(options.name, args[0], options.ns, sysname,
options.interopNS,
+                 destUrl)
+        sys.exit(0)
+
+    # Trigger mode: currently only supports SFCB Test_Indication provider.
+    if options.trigger:
+        classname = "Test_Indication"
+        sub = CIMIndicationSubscription(options.name, classname,
options.ns,
+                                    options.print_ind, sysname,
options.port,
+                                    options.interopNS, destUrl, True)
+        print "Triggering indication for %s" % classname
+        sub.trigger(options.url, auth)
         sys.exit(0)
 
     sub = CIMIndicationSubscription(options.name, args[0], options.ns,
-                                    options.print_ind, sysname,
options.port)
+                                    options.print_ind, sysname,
options.port,
+                                    options.interopNS, destUrl)
+
+    print "Creating subscription for %s" % args[0]
     sub.subscribe(options.url, auth)
     print "Watching for %s" % args[0]
 
     try:
         sub.server.serve_forever()
-    except KeyboardInterrupt,e:
-        sub.unsubscribe(auth)
+    except KeyboardInterrupt as e:
         print "Cancelling subscription for %s" % args[0]
+        sub.unsubscribe(auth)
 
 if __name__=="__main__":
     sys.exit(main())


    

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cimtest - add SSL support to indication_tester.py