href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com</a></p>
<p>Originally written: 11/13/2012; last Web page update:
-1/16/2013, referencing rEFInd 0.6.5</p>
+3/18/2013, referencing rEFInd 0.6.8</p>
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<p>Through 2012, it became obvious that Secure Boot would be a feature that was controlled, to a large extent, by Microsoft. This is because Microsoft requires that non-server computers that display Windows 8 logos ship with Secure Boot enabled. As a practical matter, this also means that such computers ship with Microsoft's keys in their firmware. In the absence of an industry-standard body to manage the signing of Secure Boot keys, this means that Microsoft's key is the only one that's more-or-less guaranteed to be installed on the computer, thus blocking the ability to boot any OS that lacks a boot path through Microsoft's signing key.</p>
+<p class="sidebar"><b>Note:</b> The <a href="http://www.linuxfoundation.org">Linux Foundation</a> has released a signed version of their <a href="http://blog.hansenpartnership.com/linux-foundation-secure-boot-system-released/">PreBootloader,</a> which functions something like shim; however, where shim requires signing all binaries that don't already have valid Secure Boot keys and managing a small number of keys, PreBootloader requires registering every authorized binary. I haven't had the chance to revise this documentation to cover PreBootloader, but you may want to use it instead of shim if you want to manage a small number of binaries that are not already signed with a Secure Boot key, MOK, or a key built into a signed version of shim.</p>
+
<p>Fortunately, Microsoft will sign third-party binaries with their key—or more precisely, with a key that Microsoft uses to sign third-party binaries. (Microsoft uses another key to sign its own binaries, and some devices, such as the Microsoft Surface tablet, lack the third-party Microsoft key.) A payment of $99 to Verisign enables a software distributor to sign as many binaries as desired. Red Hat (Fedora), Novell (SUSE), and Canonical (Ubuntu) have all announced plans to take advantage of this system. Unfortunately, using a third-party signing service is an awkward solution for open source software. In fact, for this very reason Red Hat has developed a program that it calls <i>shim</i> that essentially shifts the Secure Boot "train" from Microsoft's proprietary "track" to one that's more friendly to open source authors. Shim is signed by Microsoft and redirects the boot process to another boot loader that can be signed with keys that the distribution maintains and that are built into shim. Fedora 18 also uses this system. SUSE has announced that it will use the same system, as does Ubuntu with version 12.10 and later. SUSE has contributed to the shim approach by providing expansions to shim that support a set of keys that users can maintain themselves. These keys are known as Machine Owner Keys (MOKs), and managing them is described later, in <a href="#mok">Managing MOKs.</a> To reiterate, then, there are potentially three ways to sign a binary that will get it launched on a computer that uses shim:</p>
<ul>
<ul>
-<li><b>shim</b>—You can download a version of shim signed with Microsoft's Secure Boot key <a href="http://www.codon.org.uk/~mjg59/shim-signed/">here.</a> This version (created by shim's developer, former Red Hat employee Matthew J. Garrett) includes a shim key that's used by nothing but the <tt>MokManager.efi</tt> program that also ships with the program. Thus, to use this version of shim, you must use MOKs.
Ubuntu 12.10 ships with its own shim, but that version doesn't support MOKs and so is useless for launching rEFInd. Future versions of Fedora, SUSE, and probably other distributions will come with their own variants of shim, most of which will no doubt support their own shim keys as well as MOKs. You should install shim just as you would install other EFI boot loaders, as described <a href="http://www.rodsbooks.com/efi-bootloaders/installation.html">here.</a> For use in launching rEFInd, it makes sense to install <tt>shim.efi</tt> in <tt>EFI/refind</tt> on your ESP, although of course this detail is up to you.</li>
+<li><b>shim</b>—You can download a version of shim signed with Microsoft's Secure Boot key <a href="http://www.codon.org.uk/~mjg59/shim-signed/">here.</a> This version (created by shim's developer, former Red Hat employee Matthew J. Garrett) includes a shim key that's used by nothing but the <tt>MokManager.efi</tt> program that also ships with the program. Thus, to use this version of shim, you must use MOKs.
Fedora 18's version of shim includes its own key but can also use MOKs; but to use it with rEFInd, you must still enroll rEFInd's MOK. Ubuntu 12.10 ships with its own shim, but that version doesn't support MOKs and so is useless for launching rEFInd. Future versions of SUSE and probably other distributions will come with their own variants of shim, most of which will no doubt support their own shim keys as well as MOKs. You should install shim just as you would install other EFI boot loaders, as described <a href="http://www.rodsbooks.com/efi-bootloaders/installation.html">here.</a> For use in launching rEFInd, it makes sense to install <tt>shim.efi</tt> in <tt>EFI/refind</tt> on your ESP, although of course this detail is up to you.</li>
<li><b>MokManager</b>—This program is included with shim 0.2 and later. It presents a crude user interface for managing MOKs, and it's launched by shim if shim can't find its default boot loader (generally <tt>grubx64.efi</tt>) or if that program isn't properly signed. In principle, this program could be signed with a Secure Boot key or a MOK, but the binary in Garrett's shim 0.2 is signed with a shim key, and I expect that versions distributed with most Linux distributions will also be signed by their respective shim keys. This program should reside in the same directory as <tt>shim.efi</tt>, under the name <tt>MokManager.efi</tt>. Although you could theoretically do without MokManager, in practice you'll need it at least temporarily to install the MOK with which rEFInd is signed.</li>
have to wait for future shim developments if you want to use Secure
Boot on <i>x</i>86 or ARM computers.</li>
-<li>I currently lack a Windows 8 installation with which to test, so I can't
- even be 100% positive that rEFInd will launch Windows 8 in Secure Boot
- ode. (It should, though, since it can launch other boot loaders that have
- been signed with Microsoft's keys.) In theory, signing Microsoft's boot
- loader with a MOK should work. This might be handy if you want to replace
- your computer's built-in keys with your own but still boot Windows—but
- be aware that if Windows replaces its boot loader, it will then stop
- working.</li>
+<li>In theory, signing Microsoft's boot loader with a MOK should work. This
+ might be handy if you want to replace your computer's built-in keys
+ with your own but still boot Windows—but be aware that if Windows
+ replaces its boot loader, it will then stop working.</li>
</ul>