From Fedora Project Wiki

m (Crobinso moved page Testing secureboot with KVM to Using UEFI with QEMU: Page isn't specific to secureboot, making the title more accurate)
(Update secureboot steps, now massively simplified with latest uefi/virt support)
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     --boot loader_type=pflash,loader_ro=yes,loader=/usr/share/edk2.git/ovmf-x64/OVMF_CODE-pure-efi.fd,nvram_template=/usr/share/edk2.git/ovmf-x64/OVMF_VARS-pure-efi.fd \
 
     --boot loader_type=pflash,loader_ro=yes,loader=/usr/share/edk2.git/ovmf-x64/OVMF_CODE-pure-efi.fd,nvram_template=/usr/share/edk2.git/ovmf-x64/OVMF_VARS-pure-efi.fd \
 
     --location https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Fedora/x86_64/os/
 
     --location https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Fedora/x86_64/os/
 
== Booting the VM with OVMF ==
 
 
If Fedora doesn't boot, try the following steps. First you'll need to be at the EFI Internal Shell. If you see a 'Shell> ' prompt you are in the shell.
 
If OVMF doesn't drop you into the EFI Internal Shell automatically, do the following:
 
 
# Wait until the TianoCore splash screen pops up, hit ESC
 
# Select 'Boot Manager'
 
# Select 'EFI Internal Shell'
 
 
Once in the EFI Internal Shell, here are the commands you need to boot Fedora (assuming your guest only has a CDROM attached):
 
 
  fs0:
 
  \EFI\fedora\shim.efi
 
 
The above commands just get Fedora going, we haven't set up secure boot yet.
 
  
 
= Testing Secureboot in a VM =
 
= Testing Secureboot in a VM =
Line 59: Line 43:
 
Since OVMF doesn't ship with any SecureBoot keys installed, we need to
 
Since OVMF doesn't ship with any SecureBoot keys installed, we need to
 
install some to mimic what an MS certified UEFI machine will ship with.
 
install some to mimic what an MS certified UEFI machine will ship with.
But here's a crappy thing about OVMF and KVM: right now there's no way to
 
persist UEFI config across VM start/stop, although we'll come close with the script we'll create below.
 
{{admon/note|Improvements in Fedora 20|
 
With qemu 1.6 and later, a ''-pflash bios.bin'' option, is supposed to enable persistent EFI variables.  This may or may not also require ''-no-kvm''.}}
 
So if we want to test SecureBoot,
 
we need to install the MS keys and enable secureboot on every VM restart.
 
 
 
Luckily there's a tool that does all this for us, called LockDown_ms.efi.
 
Luckily there's a tool that does all this for us, called LockDown_ms.efi.
 
This is derived from code in [http://git.kernel.org/?p=linux/kernel/git/jejb/efitools.git;a=summary efitools.git].
 
This is derived from code in [http://git.kernel.org/?p=linux/kernel/git/jejb/efitools.git;a=summary efitools.git].
Line 72: Line 49:
  
 
   sudo wget http://fedorapeople.org/~crobinso/secureboot/LockDown_ms.efi -O /boot/efi/EFI/fedora/LockDown_ms.efi
 
   sudo wget http://fedorapeople.org/~crobinso/secureboot/LockDown_ms.efi -O /boot/efi/EFI/fedora/LockDown_ms.efi
 +
 
 +
Now we need to enroll the keys in UEFI.
  
== Automate SecureBoot startup ==
+
* Reboot the VM
 
+
* When the TianoCore splash screen pops up, hit ESC
As mentioned above, we have to install the MS keys and enable secureboot on every VM restart. Luckily, OVMF by default runs a script at startup, called startup.nsh. We'll use this to automate startup. All we really need in the script are the following commands:
+
* Select 'Boot Manager'
 
+
* Select 'EFI Internal Shell'
  fs0:
+
* Hit ESC to skip startup.nsh, or wait for the 5 second timeout.
  \EFI\fedora\LockDown_ms.efi
+
* Shell> fs0:
  \EFI\fedora\shim.efi
+
* FS0:\> \EFI\fedora\LockDown_ms.efi
 
+
* FS0:\> reset
But, life is complicated by the fact that if you are rebooting the VM where LockDown_ms.efi has been loaded, it can't be loaded a second time (without powering off the VM). If you try, you'll get a "Error reported: Security Violation" message when loading LockDown_ms.efi and the script will stop. So, the script needs to check if SecureBoot is already on before trying to load LockDown_ms.efi.
+
* The VM will restart. Let it boot into Fedora as normal. Log in
 
+
* You should see the string 'Secure boot enabled' in dmesg. Secureboot is now enabled for every subsequent boot.
Inside the guest, as root edit /boot/efi/startup.nsh and add the following text:
 
 
 
  fs0:
 
  # If we don't have the secure boot dmp file, assume this is the first
 
  # time this script has been run and secure boot is off.
 
  set __lockdown 0
 
  if not exist SecureBoot.dmp then
 
    set __lockdown 1
 
  # Otherwise we check the current state of the 'SecureBoot' variable
 
  # to see if LockDown_ms.efi has already been loaded.
 
  else
 
    dmpstore SecureBoot -s SecureBoot.tmp
 
    comp SecureBoot.dmp SecureBoot.tmp
 
    if not %lasterror% == 0 then
 
      set __lockdown 1
 
    endif
 
    rm SecureBoot.tmp
 
  endif
 
  if %__lockdown% == 1 then
 
    \EFI\fedora\LockDown_ms.efi
 
    dmpstore SecureBoot -s SecureBoot.dmp
 
  endif
 
  \EFI\fedora\shim.efi
 
 
 
== Verify SecureBoot ==
 
 
 
At this point reboot the guest. After logging in, you should see 'Secure boot enabled' in dmesg. Success!
 
 
 
== Testing F18 DVD Secure Boot in a VM ==
 
 
 
Since we can't easily alter the DVD to add LockDown_ms.efi, we get it into
 
the VM using a mini disk image:
 
  
  wget http://fedorapeople.org/~crobinso/secureboot/lockdown.qcow2
+
== Testing Fedora CD/DVD Secure Boot in a VM ==
  sudo virsh attach-disk $VMNAME --target hdb --source lockdown.qcow2 --subdriver qcow2 --config
 
  
Then do
+
Once you have a secureboot configured VM as described above, it's easy to use this to test ISO media secureboot support.
  
* Launch the VM, drop to the EFI shell
+
* Use virt-manager to attach the ISO media to your VM
* If your guest only has a CDROM attached, lockdown.qcow2 should be fs0
+
* Use virt-manager to change the VM boot settings to boot off the CDROM
* <code>Shell> fs0:</code>
+
* Start the VM
* <code>fs0:\> LockDown_ms.efi </code>
+
* Switch to a terminal inside the VM, verify Secureboot is enabled by checking dmesg
* <code>fs0:\> exit </code>
 
* Back in the config screen, Select 'Boot Manager'
 
* Select 'EFI DVD/CDROM'
 
* Once anaconda starts, grab shell, log in, verify secure boot is enabled
 
  
 
= Notes =
 
= Notes =

Revision as of 20:51, 23 November 2014

Using UEFI in a QEMU/KVM VM

Installing 'UEFI for QEMU' nightly builds

UEFI for x86 QEMU/KVM VMs is called OVMF (Open Virtual Machine Firmware). It comes from EDK2 (EFI Development Kit), which is the UEFI reference implementation.

Unfortunately there are licensing issues which prevent us getting EDK2/OVMF into Fedora (see #EDK2 Licensing Issues for more info). So we have to grab external packages.

Gerd Hoffman, Red Hatter and QEMU developer, has a yum repo on his personal site that provides nightly builds of a whole bunch of QEMU/KVM firmware, including EDK2/OVMF.

Here's how to pull down the nightly builds for x86:

 sudo wget http://www.kraxel.org/repos/firmware.repo -O /etc/yum.repos.d/firmware.repo
 sudo yum install edk2.git-ovmf-x64

Install a Fedora VM with UEFI

Note.png
This examples assume you are using Fedora 21 packages.
UEFI VMs can be installed with older Fedora versions, but since as of Fedora 21 this stuff is still under active development, it's recommended to run the latest bits.

First we need to install a guest using UEFI instead of traditional bios. Anaconda will put all the right bits in place for us.

Here's an example F20 install:

 sudo virt-install --name f20-uefi \
   --ram 2048 --disk size=20 \
   --boot loader_type=pflash,loader_ro=yes,loader=/usr/share/edk2.git/ovmf-x64/OVMF_CODE-pure-efi.fd,nvram_template=/usr/share/edk2.git/ovmf-x64/OVMF_VARS-pure-efi.fd \
   --location https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Fedora/x86_64/os/

Testing Secureboot in a VM

These steps describe how to test Fedora Secureboot support inside a KVM VM. The audience here is QA folks that want to test secureboot, and any other curious parties. This requires configuring the VM to use UEFI, so it builds upon the previous UEFI steps.

Grab LockDown_ms.efi

Since OVMF doesn't ship with any SecureBoot keys installed, we need to install some to mimic what an MS certified UEFI machine will ship with. Luckily there's a tool that does all this for us, called LockDown_ms.efi. This is derived from code in efitools.git.

Inside the guest, do:

 sudo wget http://fedorapeople.org/~crobinso/secureboot/LockDown_ms.efi -O /boot/efi/EFI/fedora/LockDown_ms.efi
 

Now we need to enroll the keys in UEFI.

  • Reboot the VM
  • When the TianoCore splash screen pops up, hit ESC
  • Select 'Boot Manager'
  • Select 'EFI Internal Shell'
  • Hit ESC to skip startup.nsh, or wait for the 5 second timeout.
  • Shell> fs0:
  • FS0:\> \EFI\fedora\LockDown_ms.efi
  • FS0:\> reset
  • The VM will restart. Let it boot into Fedora as normal. Log in
  • You should see the string 'Secure boot enabled' in dmesg. Secureboot is now enabled for every subsequent boot.

Testing Fedora CD/DVD Secure Boot in a VM

Once you have a secureboot configured VM as described above, it's easy to use this to test ISO media secureboot support.

  • Use virt-manager to attach the ISO media to your VM
  • Use virt-manager to change the VM boot settings to boot off the CDROM
  • Start the VM
  • Switch to a terminal inside the VM, verify Secureboot is enabled by checking dmesg

Notes

EDK2 Licensing Issues

EDK2 contains a FAT filesystem driver that is licensed under terms that make it not acceptable for packaging in Fedora. Particularly that there's a usage restricition only allowing the code to be used in a UEFI implementation. More details here at Edk2-fat-driver

The driver is critical functionality so removing it is not an option.

Using UEFI with AArch64 VMs

Fedora's AArch64 releases will only run on UEFI, so require UEFI inside the VM. However the steps are slightly different. See this page for complete documentation: https://fedoraproject.org/wiki/Architectures/AArch64/Install_with_QEMU

Extra links