DYLD detayled

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DYLD detayled

Postby morpheus » Thu Aug 08, 2013 2:36 am

A detailed discussion of OS X and iOS's Dynamic Linker - DYLD - and the LINKEDIT segment contents. Picks up where the book (pages 116-121) left off. Comments and feedback welcome
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Re: DYLD detayled

Postby topley » Mon Nov 30, 2015 6:45 pm

Administrator wrote:A detailed discussion of OS X and iOS's Dynamic Linker - DYLD - and the LINKEDIT segment contents. Picks up where the book (pages 116-121) left off. Comments and feedback welcome


I would like to read this article, but I don't see a link to it.
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Re: DYLD detayled

Postby morpheus » Thu Dec 03, 2015 3:52 am

It's right there in the articles page..

http://newosxbook.com/index.php?page=notes
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Re: DYLD detayled

Postby rodeman » Fri Aug 24, 2018 10:28 am

after read your article I understand the bind's meaning, but what does the rebase operation actually do ?
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Re: DYLD detayled

Postby morpheus » Fri Aug 24, 2018 5:11 pm

Rebase is for encoding pointer locations, so DYLD can get the ASLR slide value and apply it, in turn, to each of the pointers specified by the opcode stream.
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Re: DYLD detayled

Postby rodeman » Mon Aug 27, 2018 7:27 am

thank you very much !

I use the " dyldinfo -rebase " command to show the rebase info for the simple hello world program, the output is same with the "dyldinfo -rebase " command. but in apple's video(https://developer.apple.com/videos/play ... /?time=982), they said "the rebasing is adding slide for the pointers inside the image", however the dyldinfo's output are all about pointers outside the image, why ?
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Re: DYLD detayled

Postby morpheus » Tue Aug 28, 2018 8:27 pm

The pointers are inside the image , but their values are outside the image. So there's no real contradiction. The pointers are in the __DATA segment, but their values cannot be determined until the image (executable Mach-o) is linked with other libraries.
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Re: DYLD detayled

Postby rodeman » Wed Aug 29, 2018 3:07 am

ok,thank you very much ! I got it
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