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  12   <h1>The rEFInd Boot Manager:<br />Managing Secure Boot</h1>
  13
  14   <p class="subhead">by Roderick W. Smith, <a
  15 href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com</a></p>
  16
  17 <p>Originally written: 11/13/2012; last Web page update:
  18 1/8/2013, referencing rEFInd 0.6.4</p>
  19
  20
  21 <p>I'm a technical writer and consultant specializing in Linux technologies. This Web page is provided free of charge and with no annoying outside ads; however, I did take time to prepare it, and Web hosting does cost money. If you find this Web page useful, please consider making a small donation to help keep this site up and running. Thanks!</p>
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  86
  87 <hr />
  88
  89 <p>This page is part of the documentation for the rEFInd boot manager. If a Web search has brought you here, you may want to start at the <a href="index.html">main page.</a></p>
  90
  91 <hr />
  92
  93 <p class="sidebar"><b>Note:</b> My <a href="http://www.rodsbooks.com/efi-bootloaders/">Managing EFI Boot Loaders for Linux</a> Web page includes a much more detailed description of Secure Boot in its <a href="http://www.rodsbooks.com/efi-bootloaders/secureboot.html">Dealing with Secure Boot</a> sub-page. You should consult this page if you want to disable Secure Boot, generate your own keys, or perform other such tasks.</p>
  94
  95 <div class="navbar">
  96
  97 <h4 class="tight">Contents</h4>
  98
  99 <ul>
 100
 101 <li class="tight"><a href="#basic">Basic Issues</li>
 102
 103 <li class="tight"><a href="#installation">Installation Issues</a></li>
 104
 105 <li class="tight"><a href="#mok">Managing Your MOKs</a></li>
 106
 107 <li class="tight"><a href="#caveats">Secure Boot Caveats</a></li>
 108
 109 </ul>
 110
 111 </div>
 112
 113 <p>If you're using a computer that supports Secure Boot, you may run into extra complications. This feature is intended to make it difficult for malware to insert itself early into the computer's boot process. Unfortunately, it also complicates multi-boot configurations such as those that rEFInd is intended to manage. This page describes some <a href="#basic">secure boot basics</a> and two specific aspects of rEFInd and its interactions with Secure Boot: <a href="#installation">installation issues</a> and <a href="#mok">MOK management.</a> It concludes with a look at <a href="#caveats">known bugs and limitations</a> in rEFInd's Secure Boot features.</p>
 114
 115 <a name="basic">
 116 <h2>Basic Issues</h2>
 117 </a>
 118
 119 <p class="sidebar"><b>Note:</b> You don't <i>have to</i> use Secure Boot.
 120 If you don't want it, you can <a
 121 href="http://www.rodsbooks.com/efi-bootloaders/secureboot.html#disable">disable
 122 it,</a> at least on <i>x</i>86-64 PCs. If an ARM-based computer ships with
 123 Windows 8, this isn't an option for it. Unfortunately, the shim software
 124 described on this page currently supports only <i>x</i>86-64, not
 125 <i>x</i>86 or ARM.</p>
 126
 127 <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>
 128
 129 <p>Fortunately, Microsoft will sign third-party binaries with their key&mdash;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 is expected to use 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>
 130
 131 <ul>
 132
 133 <li><b>Secure Boot keys</b>&mdash;These keys are managed by the EFI
 134     firmware. In a default configuration, Microsoft is the only party
 135     that's more-or-less guaranteed to be able to sign boot loaders with
 136     these keys; however, it's possible to <a
 137     href="http://www.rodsbooks.com/efi-bootloaders/secureboot.html#add_keys">replace
 138     Microsoft's keys with your own,</a> in order to take full control of
 139     Secure Boot on your computer. The trouble is that this process is
 140     tedious and varies in details from one computer to another.</li>
 141
 142 <li><b>Shim's built-in keys</b>&mdash;It's possible, but not necessary, to
 143     compile shim with a built-in public key. Its private counterpart can
 144     then be used to sign binaries. In practice, this key type is limited in
 145     utility; it's likely to be used by distribution maintainers to sign
 146     their own version of GRUB and the Linux kernels that it launches,
 147     nothing more. On the plus side, shim's keys require little or no
 148     maintenance by users. One potential complication is that if you swap
 149     out one shim binary for another, its built-in key may change, which
 150     means that the replacement shim might no longer launch its follow-on
 151     boot loader.</li>
 152
 153 <li><b>MOKs</b>&mdash;Versions 0.2 and later of shim support MOKs, which
 154     give you the ability to add your own keys to the computer. If you want
 155     to install multiple Linux distributions in Secure Boot mode, MOKs are
 156     likely to be helpful. They're vital if you want to launch kernels you
 157     compile yourself or use boot managers or boot loaders other than those
 158     provided by your distribution.</li>
 159
 160 </ul>
 161
 162 <p>All three key types are the same in form&mdash;shim's built-in keys and MOKs are both generated using the same tools used to generate Secure Boot keys. The keys can be generated with the common <tt>openssl</tt> program, but signing EFI binaries requires a rarer program called <tt>sbsign</tt> or <tt>pesign</tt>. Although it's theoretically possible to use rEFInd without signing your own binaries, this is not yet practical, because distributions don't yet provide their own signed binaries or the public MOK files you must have to enroll their keys. With any luck this will change in 2013. At the very least, many distributions will begin supporting Secure Boot in the near future, and with any luck they'll include their public MOKs for use with other distributions' versions of shim.</p>
 163
 164 <p>Because shim and MOK are being supported by several of the major players in the Linux world, I've decided to do the same with rEFInd. Beginning with version 0.5.0, rEFInd can communicate with the shim system to authenticate boot loaders. If a boot loader has been signed by a valid UEFI Secure Boot key, a valid shim key, or a valid MOK key, rEFInd will launch it. rEFInd will also launch unsigned boot loaders or those with invalid signatures <i>if</i> Secure Boot is disabled in or unsupported by the firmware. (If that's your situation, you needn't bother reading this page.)</p>
 165
 166 <p>Version 0.5.0 ships signed with my own keys, and I provide the public version of this key with the rEFInd package. This can help simplify setup, since you needn't generate your own keys to get rEFInd working; however, without public keys for the boot loaders that rEFInd launches, you'll still need to generate keys and sign your boot loaders, as described in the <a href="#mok">Managing Your MOKs</a> section.</p>
 167
 168 <a name="installation">
 169 <h2>Installation Issues</h2>
 170 </a>
 171
 172 <p>A working Secure Boot installation of rEFInd involves at least three programs, and probably four or more, each of which must be installed in a specific way:</p>
 173
 174 <ul>
 175
 176 <li><b>shim</b>&mdash;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>
 177
 178 <li><b>MokManager</b>&mdash;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>
 179
 180 <li><b>rEFInd</b>&mdash;Naturally, you need rEFInd. Because shim is hard-coded to launch a program called <tt>grubx64.efi</tt>, you must install rEFInd using that name and to the same directory in which <tt>shim.efi</tt> resides. In theory, rEFInd could be signed with a Secure Boot key, a shim key, or a MOK; however, because Microsoft won't sign binaries distributed under the GPLv3, I can't distribute a version of rEFInd signed with Microsoft's Secure Boot key; and as I don't have access to the private shim keys used by any distribution, I can't distribute a rEFInd binary signed by them. (If distributions begin including rEFInd in their package sets, though, such distribution-provided binaries could be signed with the distributions' shim keys.) Thus, rEFInd will normally be signed by a MOK. Beginning with version 0.5.0, rEFInd binaries that I provide are signed by me. Beginning with version 0.5.1, the installation script provides an option to sign the rEFInd binary with your own key, provided the necessary support software is installed.</li>
 181
 182 <li><b>Your boot loaders and kernels</b>&mdash;Your OS boot loaders, and perhaps your Linux kernels, must be signed. They can be signed with any of the three key types. Indeed, your system may have a mix of all three types&mdash;a Windows 8 boot loader will most likely be signed with Microsoft's Secure Boot key, GRUB and kernels provided by most distributions will be signed with their own shim keys, and if you use your own locally-compiled kernel or a boot loader from an unusual source you may need to sign it with a MOK. Aside from signing, these files can be installed in exactly the same way as if your computer were not using Secure Boot.</li>
 183
 184 </ul>
 185
 186 <p>Because of variables such as which version of shim you're using and whether you're installing a pre-signed version of rEFInd or want to sign it yourself, I can't provide an absolutely complete procedure for installing rEFInd to work with Secure Boot. Broadly speaking, though, the procedure should be something like this:</p>
 187
 188 <ol>
 189
 190 <li>Boot the computer. This can be a challenge in and of itself. You may
 191     need to use a Secure Boot&ndash;enabled Linux emergency disc,
 192     temporarily disable Secure Boot, or do the work from Windows.</li>
 193
 194 <li><a href="getting.html">Download rEFInd</a> in binary form (the binary
 195     zip or CD-R image file). If you download the binary zip file, unzip it;
 196     if you get the CD-R image file, burn it to a CD-R and mount it.</li>
 197
 198 <li>Download shim from <a
 199     href="http://www.codon.org.uk/~mjg59/shim-signed/">Matthew J. Garrett's
 200     download site</a> or from your distribution. (Don't use Ubuntu 12.10's
 201     version, though; as noted earlier, it's inadequate for use with
 202     rEFInd.) The most recent beta versions of Fedora 18 reportedly ship
 203     with a signed shim, but I've not yet tested them.</li>
 204
 205 <p class="sidebar"><b>Tip:</b> If you're running Linux, you can save some effort by using the <tt>install.sh</tt> script with its <tt>--shim <tt class="variable">/path/to/shim.efi</tt></tt> option rather than installing manually, as in steps 4&ndash;6 of this procedure. If you've installed <tt>openssl</tt> and <tt>sbsign</tt>, using <tt>--localkeys</tt> will generate local signing keys and re-sign the rEFInd binaries with your own key, too. You can then use <tt>sbsign</tt> and the keys in <tt>/etc/refind.d/keys</tt> to sign your kernels or boot loaders.</p>
 206
 207 <li>Copy the <tt>shim.efi</tt> and <tt>MokManager.efi</tt> binaries to the
 208     directory you intend to use for rEFInd&mdash;for instance,
 209     <tt>EFI/refind</tt> on the ESP.</li>
 210
 211 <li>Follow the installation instructions for rEFInd on the <a
 212     href="installing.html">Installing rEFInd</a> page; however, give rEFInd
 213     the filename <tt>grubx64.efi</tt> and register <tt>shim.efi</tt> with
 214     the EFI by using <tt>efibootmgr</tt> in Linux or <tt>bcdedit</tt> in
 215     Windows. Be sure that rEFInd (as <tt>grubx64.efi</tt>),
 216     <tt>shim.efi</tt>, and <tt>MokManager.efi</tt> all reside in the same
 217     directory.</li>
 218
 219 <li>Copy the <tt>refind.cer</tt> file from the rEFInd package to your ESP,
 220     ideally to a location with few other files. (The rEFInd installation
 221     directory should work fine.)</li>
 222
 223 <li>Reboot. With any luck, you'll see a simple text-mode user interface
 224     with a label of <tt>Shim UEFI key management</tt>. This is the
 225     MokManager program, which shim launched when rEFInd failed verification
 226     because its key is not yet enrolled.</li>
 227
 228 <li>Press your down arrow key and press Enter to select <tt>Enroll key from
 229     disk</tt>. The screen will clear and prompt you to select a key, as
 230     shown here:</li>
 231
 232     <br /><IMG SRC="MokManager1.png" ALIGN="CENTER" WIDTH="676"
 233     HEIGHT="186" ALT="MokManager's user interface is crude but effective."
 234     BORDER=2> <br />
 235
 236 <li>Each of the lines with a long awkward string represents a disk
 237     partition. Select one and you'll see a list of files. Continue
 238     selecting subdirectories until you find the <tt>refind.cer</tt> file
 239     you copied to the ESP earlier. (Note that the long lines can wrap
 240     and hide valid entries on the next line, so you may need to select
 241     a disk whose entry is masked by another one!)</li>
 242
 243 <li>Select <tt>refind.cer</tt>. You can type <tt class="userinput">1</tt>
 244     to view the certificate's details if you like, or skip that and type
 245     <tt class="userinput">0</tt> to enroll the key.</li>
 246
 247 <li>Back out of any directories you entered and return to the MokManager
 248     main menu.</li>
 249
 250 <li>Select <tt>Continue boot</tt> at the main menu.</li>
 251
 252 </ol>
 253
 254 <p>At this point the computer may boot into its default OS, reboot, or perhaps even hang. When you reboot it, though, rEFInd should start up in Secure Boot mode. (You can verify this by selecting the <i>About rEFInd</i> tool in the main menu. Check the <i>Platform</i> item in the resulting screen; it should verify that Secure Boot is active.) You should now be able to launch any boot loader signed with a key recognized by the firmware or by shim (including any MOKs you've enrolled). If you want to manage keys in the future, rEFInd displays a new icon in the second (tools) row you can use to launch MokManager. (This icon appears by default if MokManager is installed, but if you edit <tt>showtools</tt> in <tt>refind.conf</tt>, you must be sure to include <tt>mok_tool</tt> as an option in order to gain access to it.)</p>
 255
 256 <p>If you're using Ubuntu 12.10, you can't use its version of shim, but you can replace it with Garrett's shim. If you do so, though, you'll have to add Ubuntu's public key as a MOK, at least if you intend to launch Ubuntu's version of GRUB or launch Ubuntu-provided signed kernels. Ubuntu's public key is available in the <a href="http://archive.ubuntu.com/ubuntu/pool/main/s/shim/shim_0~20120906.bcd0a4e8-0ubuntu4.debian.tar.gz">shim_0~20120906.bcd0a4e8-0ubuntu4.debian.tar.gz</a> tarball, as <tt>canonical-uefi-ca.der</tt>. (The filename extensions <tt>.cer</tt> and <tt>.der</tt> are interchangeable for most purposes.) I've also included this key with rEFInd, in the <tt>refind/keys</tt> subdirectory of its package file. To use this key, copy it to your ESP and enroll it with MokManager. See <a href="http://falstaff.agner.ch/2012/12/12/secure-boot-implementation-of-ubuntu-12-10-quantal-quetzal/">this blog post</a> for further details on Ubuntu 12.10's handling of Secure Boot. In principle, you should be able to use shim 0.2 or later from future distributions that include it; but you must be sure that whatever you use supports MokManager.</p>
 257
 258 <a name="mok">
 259 <h2>Managing Your MOKs</h2>
 260 </a>
 261
 262 <p>The preceding instructions provided the basics of getting rEFInd up and running, including using MokManager to enroll a MOK on your computer. If you need to sign binaries, though, you'll have to use additional tools. The OpenSSL package provides the cryptographic tools necessary, but actually signing EFI binaries requires additional software. Two packages for this are available: <tt>sbsigntool</tt> and <tt>pesign</tt>. Both are available in binary form from <a href="https://build.opensuse.org/project/show?project=home%3Ajejb1%3AUEFI">this OpenSUSE Build Service (OBS)</a> repository. The following procedure uses <tt>sbsigntool</tt>. To sign your own binaries, follow these steps (you can skip the first five steps if you've used <tt>install.sh</tt>'s <tt>--localkeys</tt> option):</p>
 263
 264 <ol>
 265
 266 <li>If it's not already installed, install OpenSSL on your computer. (It
 267     normally comes in a package called <tt>openssl</tt>.)</li>
 268
 269 <li>If you did <i>not</i> re-sign your rEFInd binaries with
 270     <tt>install.sh</tt>'s <tt>--localkeys</tt> option, type the following
 271     two commands to generate your public and private keys:
 272
 273 <pre class="listing">
 274 $ <tt class="userinput">openssl req -new -x509 -newkey rsa:2048 -keyout refind_local.key \
 275   -out refind_local.crt -nodes -days 3650 -subj "/CN=Your Name/"</tt>
 276 $ <tt class="userinput">openssl x509 -in refind_local.crt -out refind_local.cer -outform DER</tt>
 277 </pre>
 278
 279     Change <tt>Your Name</tt> to your own name or other identifying
 280     characteristics, and adjust the certificate's time span (set via
 281     <tt>-days</tt>) as you see fit. If you omit the <tt>-nodes</tt> option,
 282     the program will prompt you for a passphrase for added security.
 283     Remember this, since you'll need it to sign your binaries. The result
 284     is a private key file (<tt>refind_local.key</tt>), which is highly
 285     sensitive since it's required to sign binaries, and two public keys
 286     (<tt>refind_local.crt</tt> and <tt>refind_local.cer</tt>), which can be
 287     used to verify signed binaries' authenticity. The two public key files
 288     are equivalent, but are used by different
 289     tools&mdash;<tt>sbsigntool</tt> uses <tt>refind_local.crt</tt> to sign
 290     binaries, but MokManager uses <tt>refind_local.cer</tt> to enroll the
 291     key. If you used <tt>install.sh</tt>'s <tt>--localkeys</tt> option,
 292     this step is unnecessary, since these keys have already been created
 293     and are stored in <tt>/etc/refind.d/keys</tt>.</li>
 294
 295 <li>Copy the three key files to a secure location and adjust permissions
 296     such that only you can read <tt>refind_local.key</tt>. You'll need
 297     these keys to sign future binaries, so don't discard them.</li>
 298
 299 <li>Copy the <tt>refind_local.cer</tt> file to your ESP, ideally to a
 300     location with few other files. (MokManager's user interface becomes
 301     unreliable when browsing directories with lots of files.)</li>
 302
 303 <li>Download and install the <tt>sbsigntool</tt> package. Binary links for
 304     various distributions are available from the <a
 305     href="https://build.opensuse.org/package/show?package=sbsigntools&project=home%3Ajejb1%3AUEFI">OpenSUSE
 306     Build Service</a>, or you can obtain the source code by typing <tt
 307     class="userinput">git clone
 308     git://kernel.ubuntu.com/jk/sbsigntool</tt>.</li>
 309
 310 <li>Sign your binary by typing <tt class="userinput">sbsign --key
 311     refind_local.key --cert refind_local.crt --output <tt
 312     class="variable">binary-signed.efi binary.efi</tt></tt>, adjusting the
 313     paths to the keys and the binary names.</li>
 314
 315 <li>Copy your signed binary to a suitable location on the ESP for rEFInd to
 316     locate it. Be sure to include any support files that it needs,
 317     too.</li>
 318
 319 <li>Check your <tt>refind.conf</tt> file to ensure that the
 320     <tt>showtools</tt> option is either commented out or includes
 321     <tt>mok_tool</tt> among its options.</li>
 322
 323 <li>Reboot. You can try launching the boot loader you just installed, but
 324     chances are it will generate an <tt>Access Denied</tt> message. For it
 325     to work, you must launch MokManager using the tool that rEFInd presents
 326     on its second row. You can then enroll your <tt>refind_local.cer</tt>
 327     key just as you enrolled the <tt>refind.cer</tt> key.</li>
 328
 329 </ol>
 330
 331 <p>At this point you should be able to launch the binaries you've signed. Unfortunately, there can still be problems at this point....</p>
 332
 333 <a name="caveats">
 334 <h2>Secure Boot Caveats</h2>
 335 </a>
 336
 337 <p>rEFInd's Secure Boot support is brand-new with version 0.5.0 of the program, and was revamped for version 0.6.2. I believe rEFInd 0.6.2's Secure Boot support to be significantly superior to that of previous versions, but you might still run into problems. Some issues you might encounter include the following:</p>
 338
 339 <ul>
 340
 341 <li>Under certain circumstances, the time required to launch a boot loader
 342     can increase. This is unlikely to be noticeable for the average small
 343     boot loader, but could be significant for larger boot loaders on slow
 344     filesystems, such as Linux kernels on ext2fs, ext3fs, or ReiserFS
 345     partitions.</li>
 346
 347 <li>As of version 0.6.2, rEFInd's own Secure Boot support is theoretically
 348     able to work on non-<i>x</i>86-64 platforms; however, shim 0.2 works
 349     only on <i>x</i>86-64, and rEFInd is dependent upon shim. Thus, you'll
 350     have to wait for future shim developments if you want to use Secure
 351     Boot on <i>x</i>86 or ARM computers.</li>
 352
 353 <li>I currently lack a Windows 8 installation with which to test, so I can't
 354     even be 100% positive that rEFInd will launch Windows 8 in Secure Boot
 355     ode. (It should, though, since it can launch other boot loaders that have
 356     been signed with Microsoft's keys.) In theory, signing Microsoft's boot
 357     loader with a MOK should work. This might be handy if you want to replace
 358     your computer's built-in keys with your own but still boot Windows&mdash;but
 359     be aware that if Windows replaces its boot loader, it will then stop
 360     working.</li>
 361
 362 </ul>
 363
 364 <p>If you launch a boot loader or other program from rEFInd that relies on the EFI's standard program-launching code, that program should take advantage of shim and its MOKs. For instance, if you launch <a href="http://freedesktop.org/wiki/Software/gummiboot">gummiboot</a> from rEFInd (and rEFInd from shim), gummiboot should be able to launch shim/MOK-signed Linux kernels. This is not currently true if you launch gummiboot directly from shim.</p>
 365
 366 <p>My focus in testing rEFInd's Secure Boot capabilities has been on getting Linux kernels with EFI stub loaders to launch correctly. I've done some minimal testing with GRUB 2, though. I've also tested some self-signed binaries, such as an EFI shell and MokManager. (The EFI shell launches, but will not itself launch anything that's not been signed with a UEFI Secure Boot key, even with rEFInd 0.6.2. This of course limits its utility.)</p>
 367
 368 <p>At the moment, I consider rEFInd's shim/MOK support to be of late alpha quality. I'm releasing it in this state in the hope of getting feedback from adventurous early adopters. Some of the usability improvements are dependent upon MOK-capable versions of shim being released with major distributions; such versions of shim, with kernels signed with the key that matches the one built into shim, will greatly reduce the need for users to sign boot loaders.</p>
 369
 370 <hr />
 371
 372 <p>copyright &copy; 2012&ndash;2013 by Roderick W. Smith</p>
 373
 374 <p>This document is licensed under the terms of the <a href="FDL-1.3.txt">GNU Free Documentation License (FDL), version 1.3.</a></p>
 375
 376 <p>If you have problems with or comments about this Web page, please e-mail me at <a href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com.</a> Thanks.</p>
 377
 378 <p><a href="index.html">Go to the main rEFInd page</a></p>
 379
 380 <p><a href="revisions.html">Learn about rEFInd's history</a></p>
 381
 382
 383   <p><a href="http://www.rodsbooks.com/">Return</a> to my main Web page.</p>
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