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<b><font color="#990000">SECURITY</font></b></h2>
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<font color="#000000">In default mode Grid Engine is installed without
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any additional security measures. The assumption is made that the
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Grid Engine cluster is not exposed to any malicious attacks.</font>
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<br><font color="#000000">The hosts that belong to the Grid Engine cluster
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are classified into four categories, where a host can belong to more than
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<font color="#000000">master host</font></li>
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<br><font color="#000000">Here run the Grid Engine master daemon sge_qmaster
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and the scheduler sge_schedd.</font>
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<font color="#000000">execution hosts</font></li>
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<br><font color="#000000">Here run the Grid Engine execution daemons sge_execd.
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These nodes are allowed to execute Grid Engine jobs.</font>
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<font color="#000000">administrative hosts</font></li>
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<br><font color="#000000">Administrative tasks like the granting of permissions
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and the maintenance of resources are only allowed from these hosts.</font>
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<font color="#000000">submit hosts</font></li>
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<br><font color="#000000">Submit hosts allow for submitting and controlling
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batch jobs.</font></ul>
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<font color="#000000">Apart from the host based access restrictions the
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users are classified into the categories:</font>
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<font color="#000000">managers</font></li>
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<br><font color="#000000">They have full capabilities to manipulate Grid
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<font color="#000000">operators</font></li>
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<br><font color="#000000">They can perform the same commands as managers
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apart from adding/deleting/modifying queues.</font>
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<font color="#000000">owners</font></li>
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<br><font color="#000000">They can suspend/unsuspend or enable/disable
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the queues they are registered as owners.</font>
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<font color="#000000">users</font></li>
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<br><font color="#000000">They must have a valid login on at least one
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submit and one execution host. Their access can be limited to a subset
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of them by installing access lists.</font></ul>
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<font color="#000000">These mechanisms rely on the assumption that the
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user is who he claims to be and the host is the host that it claims to
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be and that this information can be trusted.</font>
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<br><font color="#000000">To enhance the security standard there exist
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currently three approaches:</font>
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<font color="#000000"><a href="#Enhanced Security Using Reserved Ports">Grid
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Engine using reserved ports</a></font></li>
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<font color="#000000"><a href="#Enhanced Security Using Kerberos/DCE Authentication">Grid
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Engine version using Kerberos/DCE authentication</a></font></li>
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<font color="#000000"><a href="#Enhanced Security Using Kerberos">Grid
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Engine version using Kerberos</a></font></li>
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<font color="#000000"><a href="#Enhanced Security Using OpenSSL">Grid Engine
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version using SSL (work in progress)</a></font></li>
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<a NAME="Enhanced Security Using Reserved Ports"></a><font color="#990000">Enhanced
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Security Using Reserved Ports</font>
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<p><font color="#000000">The simplest security mechanism is the communication
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between Grid Engine components over reserved ports. So any client who is
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not communicating</font>
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<br><font color="#000000">from a priviledged port number is rejected. The
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mechanism used is very similar to the authentication mechanism known from
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the rsh/rlogin command suite.</font>
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<br><font color="#000000">To make use of this security mechanism the following
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steps are necessary:</font>
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<font color="#000000">the shared Grid Engine installation directory must
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be exported setuid root</font></li>
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<font color="#000000">the installation is performed as root with './install_qmaster
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-resport' for qmaster and './install_execd -resport' for execd</font></li>
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<br><font color="#000000">The client binaries are installed setuid root
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to be able to connect to Grid Engine from reserved ports.</font>
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<font color="#000000">if you are setting up a system with shared libraries,
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the libraries must be copied to a 'safe' place. The dynamic loader requires
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in general that</font></li>
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<br><font color="#000000">the libraries are installed under /usr/lib or
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some other trusted system path.</font></ul>
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<font color="#000000">What can you expect ?</font>
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<p><font color="#000000">The communication over reserved ports assures
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that only messages that are send from a port in the range 0-1023 are accepted.
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This means that only</font>
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<br><font color="#000000">a program that has been setuid root can send
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such messages. So it can be assured that the client programs you are using
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are the ones that have been</font>
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<br><font color="#000000">installed by the Grid Engine administrator.</font>
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<br><font color="#000000">This implies that the following criteria must
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<font color="#000000">there is no possibility to replace a host in the
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network by another machine e.g. a Linux laptop where the intruder can install
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<br><font color="#000000">own version of Grid Engine binaries and setuid
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<font color="#000000">the Grid Engine executables/libraries should not
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be replaceable by someone else than root (this must be checked during installation)</font></li>
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<font color="#000000">all hosts where root access can be gained are trusted</font></li>
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<font color="#000000">Here are the steps that are performed by a Grid Engine
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command as qsub using reserved ports:</font>
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<font color="#000000">qsub is started as setuid root program</font></li>
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<font color="#000000">qsub changes its effective user id to the users id
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after starting</font></li>
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<font color="#000000">client specific processing is executed and a message
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for qmaster is prepared</font></li>
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<font color="#000000">change the effective user id to root and get a socket
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file descriptor in the priviledged port space, change back to the user's
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<font color="#000000">send the message to qmaster using the file descriptor
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in the priviledged port space</font></li>
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<font color="#000000">qmaster receives the message, if it has not been
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send from the priviledged port space it will be rejected</font></li>
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<font color="#000000">check the standard Grid Engine host and user permissions
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and allow or reject the request</font></li>
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<font color="#000000">qmaster processes the request and sends back any
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<font color="#000000">This applies to any other client command.</font>
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<p><a NAME="Enhanced Security Using Kerberos/DCE Authentication"></a><font color="#990000">Enhanced
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Security Using Kerberos/DCE Authentication</font>
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<p>This GSS-API Kerberos implementation has used regularly in Grid Engine 5.3
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development and test environments and is used full-time at least one production
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site which is running Grid Engine 5.3. This
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implementation is different than the
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<font color="#990000">Enhanced Security Using Kerberos</font>
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implementation described below in that it is not a full Kerberos implementation
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but uses Kerberos to authenticate users submitting jobs and to forward user
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credentials with the job by calling security sub-programs at the appropriate times.
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This implementation does not require recompiling Grid Engine. It consists of security
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modules which can be compiled separately and are called by Grid Engine to do
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authentication and to forward the Kerberos credentials. The security sub-modules
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are called by client commands (e.g. qsub) and by the Grid Engine daemons
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(sge_qmaster, sge_execd) at the appropriate times to get and store credentials.
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The Kerberos modules are used by Grid Engine when it is running in Kerberos mode
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(i.e. For GE 5.3, the $SGE_ROOT/default/common/product_mode file contains the
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string "sgeee-kerberos" or "sge-kerberos"). The source code for this implementation
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is located in the directory gridengine/source/security/gss. The source code is
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not dependent on other Grid Engine components or libraries and can be compiled
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stand-alone. Details on how to use this implementation can be found in
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gridengine/source/security/gss/doc/gss_customer.html.
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<p>Before you start digging into this, make sure how Kerberos/DCE functions
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in general. There are many good sites out there in Netland.
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<br><font color="#000000">Grid Engine can be run in a Kerberos/DCE environment
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using the corresponding authentication mechanisms. A detailed description
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how to integrate Grid Engine in such an enviroment can be found <a href="gss/doc/gss.html">here</a>.</font>
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<p><a NAME="Enhanced Security Using Kerberos"></a><font color="#990000">Enhanced
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Security Using Kerberos</font>
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<p>This implementation isn't really usable in its current form. This code was
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developed around 1997
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for a Raytheon customer which required Kerberos security at their site. This was a
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full Kerberos implementation which used the Kerberos libraries for all communication
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between the daemons and clients. However, the code was never put into production
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and has not been used at any production sites. It was not fully tested and it has
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not been kept up-to-date with the many changes that have been put into Grid Engine
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since that time. The Kerberos support compiled into Grid Engine should be considered
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experimental. There were several reasons for not finishing this implementation
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(e.g. time and money), but the main reason was the impracticality of supporting
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this version as a product back then (long before Grid Engine was open source)
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because of export restrictions on Kerberos itself and other practical considerations.
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At that time, allowing the customer to compile the code on his own was simply not an
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option, because we didn't supply the source code to customers.
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If you need Kerberos to authenticate users who are submitting jobs to allow Grid
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Engine jobs to run with Kerberos credentials (which have been forwarded and are
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protected by encryption), then the
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<font color="#990000">Enhanced Security Using Kerberos/DCE Authentication</font>
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implementation is the way to
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go. Full authentication and encrypted communication via Kerberos between all
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Grid Engine clients (e.g. qmon, qstat) and deamons would require using the
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Kerberos code in security/krb, but sure this would involve a significant
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amount of further testing and development. A description of the integration
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and a setup example can be found in the following documents:
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<a href="krb/doc/ReleaseNotes.html">Release Notes</a></li>
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<a href="krb/doc/Implementation.html">Implementation</a></li>
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<p><a NAME="Enhanced Security Using OpenSSL"></a><font color="#990000">Enhanced
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Security Using SSL</font>
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<p><font color="#000000">A prototype of Grid Engine supporting SSL has
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been developed in the context of a diploma thesis. Although the original
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work is a bit outdated and needs adaption to the newest SSL libraries,
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it is certainly a good starting point. The original diploma thesis (in
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german) outlining the architecture of this security approach can be found
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<a href="sec/doc/diplomarbeit.ps">here.</a>
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<p>The Certificate Security Protocol has been reworked and a description
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how to deploy this version can be found <a href="sec/csp.html">here</a>
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<p>Copyright 2001 Sun Microsystems, Inc. All rights reserved.</center>