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Saturday, March 5, 2011

Cloning OSX

Mac OS X v10.5 "Leopard"

As early as Mac OS X v10.5 build 9A466 the community has maintained a version of Leopard that can run on non-Apple hardware. A hacker by the handle of BrazilMac created one of the earliest patching processes which made it convenient for users to install Mac OS X onto 3rd party hardware by using a legally obtained, retail version of Apple Mac OS X. It was utilizing the BrazilMac patch that many effortless distros of Mac OSx86 came to fruition. 
Five of the most popular builds go by the name JaS, Kalyway, iATKOS,iPC and iDeneb - although more recently these builds are on the way out as the Boot-132 method (described below) gains popularity. However, all of these compilations rely on the work of kernel hackers made by Lorem (build 9A466), SynthetiX (builds 9A499, 9A527 and 9A559), ToH (builds 9A581, 9B13 and 9B18) and more recently a group calling themselves StageXNU (now called Voodoo) (Darwin 9.4.0). Their contributions trickled down into the various Mac OSx86 installers, readily available on the internet. There continue to be refined and updated builds released, not just to maintain compatibility with Apple releases but an ever increasing number of third party components. The OSx86 community has been quick to make the necessary modifications to enable Apple's latest releases to run on non-Apple hardware. Within hours of Leopard's release, an AMD/Intel SSE2/3 Kernel Patcher was created which removed the HPET requirement from an original untouched mach_kernel file, a core component of the Mac OS.

Mac OS X v10.6 "Snow Leopard"

The OSx86 community contributed the OSx86 knowledge in OSx86-wiki and discussed OSx86 issues in the insanelymac forum. As soon as Mac OS X v10.6 was released in 2009, the community created update guides to Snow Leopard which can run on non-Apple hardware. Apple's Mac OS X v10.6 has found its way into many PC desktops and Laptops.[18] Users can update up to versions 10.6.5,[19] either flawlessly out of the box or applying a legacy kernel patch.[20] The 10.6.6 update released in January 2011 is also reported to work.[21]

Boot loaders and emulators

EFI emulation

Extensible Firmware Interface (EFI) is a specification that defines a software interface between an operating system and platform firmware. Since this method generally does not require copying or modification of Mac OS X, it is the considered to be the most legal way of installing Mac OS X on non-Apple computers.
In early November 2007, a group of hackers (fronted by a Russian hacker known as Netkas), using an already modified boot-132 source root from David Elliot (also known as dfe),[22] developed a method[23] of emulating an EFI environment using a specially modified Darwin bootloader.[24] In practical terms, this meant that regular PCs meeting a minimum set of hardware requirements could now be "seen" as real Macintosh computers by the OS, allowing the use of unmodified, "stock" Apple kernels (as long as the CPU supports it) and thus giving a more transparent and reliable operation. Several methods for real world deployment of this innovative solution have arisen all around the net. An explanation of this achievement along with a usage guide was provided by the website[25]
True EFI emulation was a highly sought after asset for the OSx86 community. Previous efforts based upon Apple’s open source Darwin Project and Hackintosh gurus allowed users to enjoy OS X on normal PCs, with patched kernels/kernel modules which simply bypassed EFI. Using the EFI patch, a Hackintosh could boot off "vanilla" (unmodified) OS X kernels and use vanilla kernel extensions. This not only allowed the system to be compatible with future system updates, but also offered increased stability. This method also circumvents one aspect of Apple's End User License Agreement, which states that the modification of non-open Source components of the OS is forbidden.[2]
In mid-2008, a new commercial product, EFi-X, was released that claims to allow full, simple booting off official Leopard install disks, and a subsequent install, without any patching required, but this is possibly a repackaging of Boot-132 technology.[26] Rebel EFI is another commercial product that also seems to use open source software.[27]
Nowadays, there is another commercial product that created by Taiwanese called Maqboot, use different kind of bootloaders (Chameleon and Bootthink) on their different level of hackintosh which they called it as MAQ, now support up to 10.6.6


Boot-132 is a bootloader provided by Apple for loading the XNU kernel.[28] In mid-2008, a new modified BOOT-132 came on to the scene.[29] This method allows users to conduct the Leopard-based OSX86 installation using a stock, retail purchased copy of Mac OS X Leopard and eradicates the necessity of a hacked installation like JaS or Kalyway (mentioned previously). The Boot-132 boot loader essentially preloads an environment on the system from which Leopard can boot and operate. The boot loader stores the necessary files (kext files) in a .img collection or simply a folder. The luxury of this new installation method includes the ability to boot and install from a retail Leopard DVD and update straight from Apple without breaking the DMCA. The only possible problem here is it breaks the Mac OS X EULA.[30]
The bootloader behaves like the linux kernel: one can use an mboot (a patched syslinux was used for the hack) compatible bootloader which tells boot-dfe about the .img file (the ramdisk or initrd, as it's known by the linux users) and boot-dfe will then use the kexts (or mkext) from it. This new boot-dfe has been tested with the retail Leopard DVD and it can boot, install and run Leopard without having to build a modified DVD.
However, this only works with compatible machines, although more recently, with the release of the Voodoo kernel,[31] AMD users have been able to run Retail. Non-Core users can run Retail by using any compatible kernel. Both methods require the placing of the hacked kernel on the boot-132 disc.

Mac OS X v10.6 "Snow Leopard"

Since the early developer builds of Mac OS X v10.6, members of the OSx86 community had been booting the new operating system using yet another bootloader provided by Russian hacker Netkas or the bootloader of the Voodoo team Chameleon. The ability to run Mac OS X on PC hardware is now largely limited by whatever hardware components exist on a machine that have neither official Mac OS X drivers nor community support from online forums. However, with supported CPUs and graphics chipsets, 64-bit variants of the Mac OS X kernel will run flawlessly on PC hardware. Most trackpads and audio chipsets are supported by the Voodoo community, albeit with some qualifications. Intel wireless chipsets, more recent Intel GPUs, and most mobile ATI GPUs remain unsupported, due to the complexity of modifying existing drivers or writing new ones from scratch without access to the manufacturer's proprietary APIs and documentations regarding the unsupported hardware.

Live DVD

In March 2007, the OSx86 community made some significant progress with the development of a Live DVD. The Live DVD allows booting to a working system with Mac OS X v10.4.8.
On January 2, 2009, InsanelyMac's Live DVD team published a new method by which a Mac OS X v10.5.x Live DVD could be produced, allowing users to boot a fully working OS X desktop from a DVD or USB flash drive.[32] The method was more reliable than previous methods, as it manipulated Apple's existing Netboot and Imageboot functionalities, and behaved as if the system was running off a network disk. It was also easier to produce, requiring only a single script be added to an existing installation, and a distribution of the live DVD has been made since. It is notable that this method has been shown to work on normal Apple Mac hardware since.

See also

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