feat(HTCondorCE): add option to submit with SSL

set UseSSLSubmission = True to a computing element and provide the local userkey and usercert files in coordination with participating Sites
as they have to configure DN of the submitting user

src/DIRAC/Resources/Computing/HTCondorCEComputingElement.py

@@ -27,6 +27,10 @@
    then one does not need to run condor daemons on the submit machine.
    If True requires the condor grid middleware (condor_submit, condor_history, condor_q, condor_rm)
 
+UseSSLSubmission:
+   If 'True', use SSL via a DN configured at the given computing element to submit jobs.
+   This is a bridge feature until everyone is capable to use Tokens to submit to computing elements.
+
 WorkingDirectory:
    Location to store the pilot and condor log files locally. It should exist on the server and be accessible (both
    readable and writeable).  Also temporary files like condor submit files are kept here. This option is only read
@@ -104,6 +108,7 @@ def __init__(self, ceUniqueID):
             gConfig.getValue("Resources/Computing/HTCondorCE/WorkingDirectory", DEFAULT_WORKINGDIRECTORY),
         )
         self.useLocalSchedd = True
+        self.useSSLSubmission = False
         self.remoteScheddOptions = ""
         self.tokenFile = None
 
@@ -217,6 +222,11 @@ def _reset(self):
             "" if self.useLocalSchedd else f"-pool {self.ceName}:{self.port} -name {self.ceName} "
         )
 
+        self.useSSLSubmission = self.ceParameters.get("UseSSLSubmission", self.useSSLSubmission)
+        if isinstance(self.useSSLSubmission, str):
+            if self.useSSLSubmission == "True":
+                self.useSSLSubmission = True
+
         self.log.debug("Using local schedd:", self.useLocalSchedd)
         self.log.debug("Remote scheduler option:", self.remoteScheddOptions)
         return S_OK()
@@ -239,6 +249,19 @@ def _executeCondorCommand(self, cmd, keepTokenFile=False):
         htcEnv = {
             "_CONDOR_SEC_CLIENT_AUTHENTICATION_METHODS": "GSI",
         }
+
+        if self.useSSLSubmission:
+            htcEnv = {
+                "_condor_SEC_CLIENT_AUTHENTICATION_METHODS": "SSL",
+                "_condor_AUTH_SSL_CLIENT_KEYFILE": "/home/dirac/.globus/userkey.pem",
+                "_condor_AUTH_SSL_CLIENT_CERTFILE": "/home/dirac/.globus/usercert.pem",
+                "_condor_AUTH_SSL_CLIENT_CADIR": "/opt/dirac/etc/grid-security/certificates/",
+                "_condor_AUTH_SSL_SERVER_CADIR": "/opt/dirac/etc/grid-security/certificates/",
+                "_condor_AUTH_SSL_USE_CLIENT_PROXY_ENV_VAR": "false",
+                "_condor_AUTH_SSL_SERVER_CAFILE": "",
+                "_condor_AUTH_SSL_CLIENT_CAFILE": "",
+            }
+
         # If a token is present, then we use it (overriding htcEnv)
         if self.token:
             # Create a new token file if we do not keep it across several calls