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<p class="MsoNormal"><span style="color:#1F497D">Take a look at the PlatformAdaptationLayer class. You can create your own and plug it in to the runtime. This might provide the hooks you are looking for.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">In particular, you should be able to override the LoadAssembly() and LoadAssemblyFromPath() methods to block anything that isn’t whitelisted for your host environment.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:14.0pt;color:#1F497D">Keith Rome<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;color:#1F497D">Senior Consultant and Architect<o:p></o:p></span></b></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#1F497D">MCPD-EAD, MCSD, MCDBA, MCTS-WPF, MCTS-TFS, MCTS-WSS<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#1F497D">Wintellect | 770.617.4016 |
<a href="mailto:rome@wintellect.com">krome@wintellect.com</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#1F497D"><a href="http://www.wintellect.com/">www.wintellect.com</a><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b>From:</b> Ironpython-users [mailto:ironpython-users-bounces+rome=wintellect.com@python.org]
<b>On Behalf Of </b>Markus Schaber<br>
<b>Sent:</b> Wednesday, October 17, 2012 6:09 AM<br>
<b>To:</b> Discussion of IronPython<br>
<b>Subject:</b> [Ironpython-users] Restrict referencing of assemblies in hosted environment<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">We’re using IronPython as a hosted script engine in our application.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Now, we want to restrict the assemblies a user can reference from its python script,
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Currently, we just forbid “import clr”, by wrapping the import() method, but this is a bit harsh, and the side-effects are a little bit to strong (e. G. it causes “import minidom.py”
to fail…)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">However, there seems to be no event or other hook available for AddReference which I could use. It may be possible to add an AssemblyLoading event to the ScriptDomainManager
in Microsoft.Scripting.Runtime, which allows to cancel the assembly loading by throwing an exception. Would such a patch be accepted upstream?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">An alternative (not-so-elegant) idea is that I just wrap all the AddReference() & Co calls inside the clr module, but there may be a more elegant way.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Isolating Ironpython in its own AppDomain is not an option, as this would require major rework of our Scripting API implementation, and also break backwards compatibility for
3<sup>rd</sup> party plugins which contribute API for the scripts.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">(We don’t need a 100% waterproof method - we know that the user can use cTypes, System.Reflection, or whatever to circumvent everything - we just want to restrict the obvious
ways to access some APIs we consider to be internal.)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="DE" style="font-size:10.0pt;font-family:"Arial","sans-serif";mso-fareast-language:DE">Best regards<br>
<br>
Markus Schaber<br>
<span style="color:white">-- </span><br>
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