November 2009 - Darwin-dev - lists.apple.com

Ovelapp of system module address in case of ASLR ?
by Arnab Ganguly 15 Nov '09

15 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:date:message-id:subject :from:to:content-type; bh=00tzdnzsml5NtszyoOCk4FJvj6h9EGnApLMlBJSZnlA=; b=AfmWDx2/SvTUyPAidC/scy/W4Mz0n9Axjl8fe6JBf/qVVaKjD219WMvEN6lTfZNp30 7qy2bvV8F+s6RK8TjZiq3C6SfStgTx+HVNCQGHc+UpH8gne8+0myqVT9QdnDX8SZLaKK jmqTh+x1FWGMIwP3JTQgiLQ61v3Oy9Uy86Ad8= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=NU5QtzUogzt67yWrnj7KNpM0BF92sC82Yp/0mom23/6H2Jl3KWjIjLiYN1+Tc4ciYx lUmda0ez8kG6GD2Q+cn+HkVf5xpVS8yD+RfdjsPReFeMaPxPd7oHckpyyXHshasK9FrX Q7ppN34A9guSgaRMAG1oi2NvFasKQzD9uIkzM= _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Open Source Releases
by William Siegrist 14 Nov '09

14 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com The Darwin Team is proud to announce the availability of the following Open Source releases: Mac OS X 10.6.2 Developer Tools 3.2.1 They are available in the usual location, at <http://opensource.apple.com/>. You will also notice pages for iPhone 3.1.1 and 3.1.2, but those releases had no new open source code to post. Thank you. William Siegrist Darwin Team _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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TCP socket filter and control/flags params to sf_data functions
by jakub 13 Nov '09

13 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hi list, I have read Network Kernel Extensions Programming Guide along with TCPlognke sample code and I have one, hopefully simple question. If I have a socket filter running on TCP protocol only (IPv4/IPv6), do I have to bother with mbuf_t control and sflt_data_flags_t flags parameters to sf_data_in_func/sf_data_out_func? Documentation to sf_data_in_func also says, that in the data buffer, control data may appear in the mbuf chain. Is this relevant for TCP? I want to pass only data to user space process (possibly modifying the data) and I don't want to keep a copy in kernel just to keep the flags and control mbuf. I haven't found any documentation discussing this in any more detail and I'm not aware of any such control/flags used on top of TCP. Can I just ignore these two and set them to 0 when re-injecting data? TCPlognke is dealing with them. Thanks a lot, Jakub _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: cross-process timeoutable semaphores
by Alastair Houghton 12 Nov '09

12 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha1; c=relaxed; d=alastairs-place.net; h= subject:mime-version:content-type:from:in-reply-to:date:cc: content-transfer-encoding:message-id:references:to; q=dns/txt; s= aug07; bh=8fyz+/ztgrR56WckbaXpzodhLIA=; b=nV8qKe1dFzGb6qnQsLlB7P sU4OfaoSIN3ipIVZUCI+94DGo+QbVtmZ8i8tpc+EGDBzxmLR+PgqVIkFteUwARxX lqi8mxjzmeMVT926q3xSl9cPHDvikZf+vwG/LATwBVEQo+0d6jl/ZqLlU3gJwTwR 57/iwIBrFRUI7JuKJKIgc= On 11 Nov 2009, at 22:18, Tyler Sample wrote: > I'm trying to port some linux code to OSX, and have the need for a cross-process timeoutable semaphore (semtimedop in particular being in the original code). This has been extremely frustrating and I'm about two weeks into trying to implement this basic mechanism (that took me about 2 hours to port from win32 to linux originally). [snip] > My last attempt has been using mach semaphores. My problem there is poor documentation. Even after studying mach and its various headers for a couple solid days, I just have no idea how to say to interested processes (which are anonymous, although with significant work I could probably change that) "here's the global port/semaphore name...request the access you need." I'm really not sure how well it will work since only one task/process can have receive rights on a semaphore/port at the same time anyway. Hi Tyler, I think you might find the following blog post (which I just wrote) interesting: <http://alastairs-place.net/2009/11/cross-process_s/> It's supposed to be a very simple example of how one might go about achieving what you were asking for here using the Mach APIs, which, as you point out, are a little difficult to "get" at first. The book "Programming under Mach" is quite a handy reference, as is Amit Singh's "Mac OS X Internals: A Systems Approach". Not entirely sure what Apple's people would say about this; IIRC they have said once or twice that use of the Mach API by third-parties is "discouraged", but in this particular instance it seems to be a reasonable solution to your specific problem. Kind regards, Alastair. -- http://alastairs-place.net _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: cross-process timeoutable semaphores
by Tyler Sample 12 Nov '09

12 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:from:to:references :in-reply-to:subject:date:mime-version:content-type :content-transfer-encoding:x-priority:x-msmail-priority:x-mailer :x-mimeole; bh=nNU9mPiMiwxVuxMgwjLXV8PuAGszpzKoH/XK9kJCSXY=; b=efR809A+LROA44guH6PDa+CSwN5Gd/luHuKWuxbYm/xX49pSEC/FlxXy7Fy/2m5aji orEP1wAasEbOqNvpSNRcI81QbAHsCx3CnwLXxMQRDuVMy1mPLmpyzZz3RawRHfreorbv XUrZG/X3UzlpcXuNOWy0Q+9UmTHVKzJyNhUMM= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:from:to:references:in-reply-to:subject:date:mime-version :content-type:content-transfer-encoding:x-priority:x-msmail-priority :x-mailer:x-mimeole; b=oUA6ySnw2gQqXXVVheezr1BhTmYkFcTdeiQTd7KxNCJ4CHU7vXCq8CfEVGCnt/QpJ3 dLt+tKkLfI6uWuE6Ie4x12ho+V+Wkdv/7lVV7A53JoUwaJhO478F10mpjUbju2PQcm2/ zWiCwSt3s2XZYMwkA0pGVAl8jG2Pdz8J1B3NM= Untested theory: can you use alarm/setitimer with SysV style semaphores? I believe SIGALRM is a synchronous signal, so would be delivered on the thread you set it on. Then you'd check your sem calls for EINTR. _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/tyler.sample%40gmail.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I had a lot of strange buggy behavior when I tried the SIGALRM approach. I didn't spend too much time digging into it with gdb or anything because the time precision (1 second intervals) might not be adequate for the performance needs of the application anyway. Also, this approach has been suggested for this problem elsewhere, and I've never seen a "that worked" response, so I'm not sure about it. If anyone has tried it and had it work, I'd love to hear it. I've thought about a similar tact where I spawn another thread to perform the blocking call on the semaphore, and then use timeoutable pthread synchs between it and the main thread, but given the app's semaphore use, I'm really not sure how many hung threads the task might end up with. Maybe acceptable, I guess, but ridiculously complicated and certainly far from optimal, especially later for anyone else trying to debug a threading issue or the like... Obviously, there's probably solutions that don't require this semaphore for the application as a whole and are more optimal. Unfortunately, I'm working in an OS abstraction layer and modifying all the code outside of it to work with some other mechanism just isn't feasible in the time I have...which I've used half of just trying to solve this one problem. Regarding this: <abdulla.kamar(a)gmail.com> From what I understand, you should be able to pass a mach semaphore over a mach port to the other process and then use semaphore_timedwait. The structure of the mach semaphore itself, which is actually a mach port right, is not valid across a task/process boundary (KERN_INVALID_NAME). Mach mechanisms seem to exist for passing port rights to another task. I guess what I need is the ability to put those port rights in named storage, probably a port, so any other task that knows the name can pick them up. If anybody more familiar with mach than me could provide any guidance, I'd certainly be appreciative, but I basically don't know mach well enough to implement cross-process semaphores in it myself. There's an open source project called Firebird that may have had luck with this approach, but I can't make heads or tails of their newest semaphore code for OSX. ----- Original Message ----- From: "Stephen J. Butler" <stephen.butler(a)gmail.com> To: "Darwin Dev" <darwin-dev(a)lists.apple.com> Sent: Wednesday, November 11, 2009 4:50 PM Subject: Re: cross-process timeoutable semaphores On Wed, Nov 11, 2009 at 4:18 PM, Tyler Sample <tyler.sample(a)gmail.com> wrote: POSIX semaphores won't work because OSX doesn't support sharing them across processes. Carbon's "multiprocess services" also, strangely, doesn't work across process boundaries. System V style semaphores are missing the ability to timeout (on OSX) This email sent to tyler.sample(a)gmail.com This email sent to site_archiver(a)lists.apple.com

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Re: cross-process timeoutable semaphores
by Abdulla Kamar 12 Nov '09

12 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :from:date:message-id:subject:to:cc:content-type; bh=UcOFUdnCMofLcvB7+d1eJOJT/zzK7KsbtWAW+DldmKU=; b=Ye3cE71TG/JEtPkpjAO3iK2XnbAw9+w5ZXTLUcFRYBKkaRO1Ph0+0ljWuVmTyjuDCj KVwiW0NOY6h/na+0nFJbcM86yN9fkrUne3MN9nob1sZUin2xGWOr4MDDjC28du6JS1D8 sQxDhCVYKENlOIikkHM2378UgtZ1wBIajV2Kg= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; b=SfaeJTYoxzJeulrVu/JDgApQv6klcsha7YckEeQZwIBQyiQhvoNeyqwaG/QP3QvCyD znmeCmJ+4EAeMjm6/lAEN75x1xqByB/GIowWSkKF+JwTbm0ab4+jsKYQCl9wOTQzmVQO ZZcjvm/ntxcsR2mpaebuTjB518qVSAwYix2tY= _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: cross-process timeoutable semaphores
by Stephen J. Butler 12 Nov '09

12 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=Bl21rbbtOaFeefIBS9vcHNCJuuL2Gp9TrAmW1kPTE1Y=; b=GhH6ZWlZhIoJxPRCReh2TzJgu+xLfpLOql9QwR6F8R6emR0Fkt1QVcKbG2F4Qi16sj aYMmxsA+z/6rwV+rcjYctKSE9QcrQAs4cOBBWZ/tX1wH5fCoqu/uJrqIizzlMIs4W/8e VYmOVwUqqy+d4HyATWrLdMDEYABw+ldJmKkt0= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=hTpan1LKQ7LR/Cyxti1lu1VPzTpgDLiM0sH0MlIf6Rr+RZRe3WysK2o5f5+x8FC5TV BgwhVuqvLqg1cR+/zzJwtKhdtAs5j1Nxu6CqGsaopfFzkBBEELHL92HcL3WZJTzzIGos RAHGK2BFpOP2XJ9GDzWkM2ZPQzCZ6EaVScz2s= On Wed, Nov 11, 2009 at 4:18 PM, Tyler Sample <tyler.sample(a)gmail.com> wrote: > POSIX semaphores won't work because OSX doesn't support sharing them across > processes. Carbon's "multiprocess services" also, strangely, doesn't work > across process boundaries. System V style semaphores are missing the > ability to timeout (on OSX) Untested theory: can you use alarm/setitimer with SysV style semaphores? I believe SIGALRM is a synchronous signal, so would be delivered on the thread you set it on. Then you'd check your sem calls for EINTR. _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: Building Objc4 on Windows
by Brent Fulgham 11 Nov '09

11 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=+QzERiKs+CNby1hzdrD8c0ZGygFVsg+vw4MKa6q/2b8=; b=HJp9tXohC1Fxpb2rKm/Nhx3jVMFAVcxyEqUniNoOs6QncmxlxbNt4xSZ+DdDF2wb9p mrkOZvoDs2uxbwoVXa1YXY2pV8s/LMj2gMqV8Q4JrHCdIgchwlZjISTGxRzlHENCC9/o zniTJZtQHUVJclk14Jpd6pmHJ1doCgCZBx1iA= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=i8+mGyHYoiQUWLBKz6di6lAfEuEEqmVqSeIDaZ3U2sOLlTlEl0ysEe9EHGt66KeSkA jHfVS5m5U8hZXT72DOJAjBXVXdprpLaO02MiVW2Dc2z95Zl1umKDbkA3XfXHE7HmIoiK McABrflVSr5o+PhPGVUG3+ZT1bRd8zdZ0nsNE= Hi Matthieu, On Mon, Nov 9, 2009 at 5:26 AM, Matthieu Cormier <Matthieu.Cormier(a)concertia.com> wrote: > More succinctly. Did you get your compiled version of objc working? > Yes, I did indeed get it to build. I checked in the (slightly modified) sources and VS 2005 project files here: http://opencflite.svn.sourceforge.net/viewvc/opencflite/objc4/. Note that building objc4 itself is fairly uninteresting. You need a corresponding set of Objc objects to load into the image for anything interesting to happen. That is what the map/unmap/load_images are meant to do. If you look over darwinbuild or perhaps even GNUstep you could probably figure out how to create a suitable kernel of objc objects. Currently, I don't need access to the runtime, so I have disabled the build in the OpenCFLite project. -Brent _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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fdatasync()
by Axel Luttgens 11 Nov '09

11 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hello, Does somebody know the current status of fdatasync()? No definition is provided in any header file for that function, and some parts in xnu's code seem to explicitely disable its functionality. Moreover, unistd.h defines _POSIX_SYNCHRONIZED_IO as having value -1. But the symbol seems to exist in libSystem (this wasn't the case with earlier versions of Mac OS X, for example Tiger). As a result, it is possible to compile code that invokes that function, but some quick tests tend to show that the function behaves at best as a kind of noop. TIA, Axel _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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cross-process timeoutable semaphores
by Tyler Sample 11 Nov '09

11 Nov '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:from:to:subject :date:mime-version:content-type:x-priority:x-msmail-priority :x-mailer:x-mimeole; bh=iIt6s3zJvgnhOEgY2FqHQqG4150fgG14WzZFvPapeAI=; b=payffzXXWEqmOBZSNi6+pAxpJ8bwcdznkftR55sFkiwiYAQri7NXWNLTZ/dmxl2nBc 1QGlfLBcsIiINMdquTXm4Zj/hh49B/FRIaLVqRYWK54CpEqFmqv0w+zawg3J786MAqyn gzgKXMI16QPAlSQaTnCaavYXvnp5Iza3n5iNg= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:from:to:subject:date:mime-version:content-type :x-priority:x-msmail-priority:x-mailer:x-mimeole; b=xtW/MbtAkXNu0VIboyQzvnTDQARh9rR1c26AYQUfm789OtRCn5DauWq+IfXLzfteSz N3gFM+H6PnRCG5/RUGQcUnmeWADLmyHsvh7WLOvF20a0bwovDn5/yfhWfGpWi8H5HNf7 pzCKKDZoN1zibWyy3n+r0kmdkmZ/9+5vWJEfs= _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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