On a Wednesday in 2022, Daniel P. Berrangé wrote:
The virt-qemu-sev-validate program will compare a reported SEV/SEV-ES
domain launch measurement, to a computed launch measurement. This
determines whether the domain has been tampered with during launch.
This initial implementation requires all inputs to be provided
explicitly, and as such can run completely offline, without any
connection to libvirt.
The tool is placed in the libvirt-client-qemu sub-RPM since it is
specific to the QEMU driver.
Signed-off-by: Daniel P. Berrangé <berrange@xxxxxxxxxx>
---
docs/manpages/meson.build | 1 +
docs/manpages/virt-qemu-sev-validate.rst | 207 ++++++++++++++++++
libvirt.spec.in | 2 +
tools/meson.build | 5 +
tools/virt-qemu-sev-validate | 263 +++++++++++++++++++++++
5 files changed, 478 insertions(+)
create mode 100644 docs/manpages/virt-qemu-sev-validate.rst
create mode 100755 tools/virt-qemu-sev-validate
diff --git a/docs/manpages/virt-qemu-sev-validate.rst b/docs/manpages/virt-qemu-sev-validate.rst
new file mode 100644
index 0000000000..36de9becfd
--- /dev/null
+++ b/docs/manpages/virt-qemu-sev-validate.rst
[...]
+Guest config options
+--------------------
+
+These options provide items needed to calculate the expected domain launch
+measurement. This will then be compared to the reported launch measurement.
+
+``-f PATH``, ``--firmware=PATH``
+
+Path to the firmware loader binary. This is the EDK2 build that knows how to
+initialize AMD SEV. For the validation to be trustworthy it important that the
+firmware build used has no support for loading non-volatile variables from
+NVRAM, even if NVRAM is expose to the guest.
+
+``--tik PATH``
+
+TIK file for domain. This file must be exactly 16 bytes in size and contains the
+unique transport integrity key associated with the domain session launch data.
+This is mutually exclusive with the ``--tk`` argument.
+
+``--tek PATH``
+
+TEK file for domain. This file must be exactly 16 bytes in size and contains the
+unique transport encryption key associated with the domain session launch data.
+This is mutually exclusive with the ``--tk`` argument.
+
+``--tek PATH``
--tk
+
+TEK/TIK combined file for the domain. This file must be exactly 32 bytes in
+size, with the first 16 bytes containing the TEK and the last 16 bytes
+containing the TIK. This is mutually exclusive with the ``--tik`` and ``--tek``
+arguments.
+
[...]
+COPYRIGHT
+=========
+
+Copyright (C) 2022 by Red Hat, Inc.
+
+
+LICENSE
+=======
+
+``virt-qemu-sev-validate`` is distributed under the terms of the GNU GPL v2+.
The license here says GPLv2+, but LGPL-2.1+ in the SPDX identifier below.
+This is free software; see the source for copying conditions. There
+is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR
+PURPOSE
+
+
diff --git a/tools/virt-qemu-sev-validate b/tools/virt-qemu-sev-validate
new file mode 100755
index 0000000000..c0837cc2c7
--- /dev/null
+++ b/tools/virt-qemu-sev-validate
@@ -0,0 +1,263 @@
+#!/usr/bin/python3
+#
+# SPDX-License-Identifier: LGPL-2.1-or-later
+#
+# Validates a guest AMD SEV launch measurement
+#
[...]
+def parse_command_line():
+ parser = argparse.ArgumentParser(
+ description='Validate guest AMD SEV launch measurement')
+ parser.add_argument('--debug', '-d', action='store_true',
+ help='Show debug information')
+ parser.add_argument('--quiet', '-q', action='store_true',
+ help='Do not display status')
+
+ # Arguments related to the state of the launched guest
+ vmstate = parser.add_argument_group("Virtual machine launch state")
+ vmstate.add_argument('--measurement', '-m', required=True,
+ help='Measurement for the running domain')
+ vmstate.add_argument('--api-major', type=int, required=True,
+ help='SEV API major version for the running domain')
+ vmstate.add_argument('--api-minor', type=int, required=True,
+ help='SEV API major version for the running domain')
*minor
+ vmstate.add_argument('--build-id', type=int, required=True,
+ help='SEV build ID for the running domain')
+ vmstate.add_argument('--policy', type=int, required=True,
+ help='SEV policy for the running domain')
+
+ # Arguments related to calculation of the expected launch measurement
+ vmconfig = parser.add_argument_group("Virtual machine config")
+ vmconfig.add_argument('--firmware', '-f', required=True,
+ help='Path to the firmware binary')
+ vmconfig.add_argument('--tik',
+ help='TIK file for domain')
+ vmconfig.add_argument('--tek',
+ help='TEK file for domain')
+ vmconfig.add_argument('--tk',
+ help='TEK/TIK combined file for domain')
+
+ return parser.parse_args()
Reviewed-by: Ján Tomko <jtomko@xxxxxxxxxx>
Jano
