site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com Hi folks, I found some interesting articles like "extending the Mach external pager interface to accommodate user-level page replacement policies". But I actually don't know how to exploit them. -- Terry _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... On Aug 27, 2008, at 5:49 AM, Nicolas CORMIER wrote: I would like to know if it is possible to create an external pager. My main goal is to decrypt encrypted pages when they are accessed at run-time. We already have an internal pager that does this; that's how "encrypted swap" works. The traditional UNIX way to deal with this inside a process address space is to fix up the SIGSEGV/SIGBUS signals by providing handlers, and then fixing up the faults when the signal handler fires. An alternative method which will work on Mac OS X because of the way signals are implemented would be to obtain the task exception port for the task, and fix up the exception when it is raised before it becomes a signal. You will also need the task port, so that you other process can fix up the address space contents in the target task. Finally, as shipped, the Leopard code still has most of the Mach external pager support intact (not ripped out). If you really want to do this, you should look at the CMU or OSF documentation on how to write external pagers. This email sent to site_archiver@lists.apple.com