[pve-devel] [PATCH guest-common/qemu-server/docs/manager v12 0/6] AMD SEV

[pve-devel] [PATCH guest-common/qemu-server/docs/manager v12 0/6] AMD SEV

[Markus Frank]

changes v12:
* new pve-guest-common patch
* improved error handling in C
* small perl style changes

changes v11:
* removed systemd service and added run_command in qemu-server instead
* moved SEV related code to CPUConfig
* instead of the no-debug and no-key-sharing checkboxes there are no 
 "allow debug/key-sharing" checkboxes in the WebUI with true beeing 
 the default.
* add check_non_migratable_resources function in qemu-server


apply/compile order:
1. pve-guest-common: AbstractConfig: add abstract method to check for resources 
 preventing a snapshot
2. qemu-server: add C program to get hardware capabilities from CPUID
3. qemu-server: config: add AMD SEV support
4. qemu-server: migration: add check_non_migratable_resources function
5. pve-docs: add AMD SEV documentation
6. pve-manager: ui: add AMD SEV configuration to Options


pve-guest-common:

Markus Frank (1):
  AbstractConfig: add abstract method to check for resources preventing
    a snapshot

 src/PVE/AbstractConfig.pm | 9 +++++++++
 1 file changed, 9 insertions(+)


qemu-server:

Markus Frank (3):
  add C program to get hardware capabilities from CPUID
  config: add AMD SEV support
  migration: add check_non_migratable_resources function

 Makefile                                      |  1 +
 PVE/API2/Qemu.pm                              |  5 +-
 PVE/QemuConfig.pm                             |  5 ++
 PVE/QemuMigrate.pm                            |  2 +-
 PVE/QemuServer.pm                             | 36 +++++++-
 PVE/QemuServer/CPUConfig.pm                   | 88 ++++++++++++++++++-
 query-machine-capabilities/Makefile           | 18 ++++
 .../query-machine-capabilities.c              | 79 +++++++++++++++++
 8 files changed, 229 insertions(+), 5 deletions(-)
 create mode 100644 query-machine-capabilities/Makefile
 create mode 100644 query-machine-capabilities/query-machine-capabilities.c


pve-docs:

Markus Frank (1):
  add AMD SEV documentation

 qm.adoc | 103 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 103 insertions(+)


pve-manager:

Markus Frank (1):
  ui: add AMD SEV configuration to Options

 www/manager6/Makefile        |   1 +
 www/manager6/qemu/Options.js |  11 ++++
 www/manager6/qemu/SevEdit.js | 121 +++++++++++++++++++++++++++++++++++
 3 files changed, 133 insertions(+)
 create mode 100644 www/manager6/qemu/SevEdit.js

-- 
2.39.5



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[pve-devel] [PATCH guest-common v12 1/6] AbstractConfig: add abstract method to check for resources preventing a snapshot

[Markus Frank]

Signed-off-by: Markus Frank <m.frank@proxmox.com>
Suggested-by: Fiona Ebner <f.ebner@proxmox.com>
---
This patch is new in v12.

 src/PVE/AbstractConfig.pm | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/PVE/AbstractConfig.pm b/src/PVE/AbstractConfig.pm
index 5d5f9b4..3d4fcbb 100644
--- a/src/PVE/AbstractConfig.pm
+++ b/src/PVE/AbstractConfig.pm
@@ -579,6 +579,13 @@ sub __snapshot_check_running {
     die "implement me - abstract method\n";
 }
 
+# Abstract method: Check if there is a resource preventing a snapshot.
+sub __snapshot_assert_no_blockers {
+    my ($class, $vmconf, $save_vmstate) = @_;
+
+    return;
+}
+
 # Check whether we need to freeze the VM/CT
 sub __snapshot_check_freeze_needed {
     my ($sself, $vmid, $config, $save_vmstate) = @_;
@@ -726,6 +733,8 @@ sub __snapshot_prepare {
 
 	$class->check_lock($conf);
 
+	$class->__snapshot_assert_no_blockers($conf, $save_vmstate);
+
 	$conf->{lock} = 'snapshot';
 
 	my $snapshots = $conf->{snapshots};
-- 
2.39.5



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[pve-devel] [PATCH qemu-server v12 2/6] add C program to get hardware capabilities from CPUID

[Markus Frank]

Implement a C program that extracts AMD SEV hardware information such
as reduced-phys-bios and cbitpos from CPUID, looks if SEV, SEV-ES &
SEV-SNP are enabled, and outputs these details as JSON to
/run/qemu-server/host-hw-capabilities.json

This program can also be used to read and save other hardware
information.

Signed-off-by: Markus Frank <m.frank@proxmox.com>
Co-authored-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
---
changes v12:
* improved error handling

 Makefile                                      |  1 +
 query-machine-capabilities/Makefile           | 18 +++++
 .../query-machine-capabilities.c              | 79 +++++++++++++++++++
 3 files changed, 98 insertions(+)
 create mode 100644 query-machine-capabilities/Makefile
 create mode 100644 query-machine-capabilities/query-machine-capabilities.c

diff --git a/Makefile b/Makefile
index 133468da..ed67fe0a 100644
--- a/Makefile
+++ b/Makefile
@@ -65,6 +65,7 @@ install: $(PKGSOURCES)
 	install -m 0644 -D bootsplash.jpg $(DESTDIR)/usr/share/$(PACKAGE)
 	$(MAKE) -C PVE install
 	$(MAKE) -C qmeventd install
+	$(MAKE) -C query-machine-capabilities install
 	$(MAKE) -C qemu-configs install
 	$(MAKE) -C vm-network-scripts install
 	install -m 0755 qm $(DESTDIR)$(SBINDIR)
diff --git a/query-machine-capabilities/Makefile b/query-machine-capabilities/Makefile
new file mode 100644
index 00000000..469c69ff
--- /dev/null
+++ b/query-machine-capabilities/Makefile
@@ -0,0 +1,18 @@
+DESTDIR=
+PREFIX=/usr
+BINDIR=${PREFIX}/libexec/qemu-server
+
+CC ?= gcc
+CFLAGS += -O2 -fanalyzer -Werror -Wall -Wextra -Wpedantic -Wtype-limits -Wl,-z,relro -std=gnu11
+
+query-machine-capabilities: query-machine-capabilities.c
+	$(CC) $(CFLAGS) -o $@ $< $(LDFLAGS)
+
+.PHONY: install
+install: query-machine-capabilities
+	install -d ${DESTDIR}/${BINDIR}
+	install -m 0755 query-machine-capabilities ${DESTDIR}${BINDIR}
+
+.PHONY: clean
+clean:
+	rm -f query-machine-capabilities
diff --git a/query-machine-capabilities/query-machine-capabilities.c b/query-machine-capabilities/query-machine-capabilities.c
new file mode 100644
index 00000000..c31ed118
--- /dev/null
+++ b/query-machine-capabilities/query-machine-capabilities.c
@@ -0,0 +1,79 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <string.h>
+
+int main() {
+    uint32_t eax, ebx, ecx, edx;
+
+    // query Encrypted Memory Capabilities, see:
+    // https://en.wikipedia.org/wiki/CPUID#EAX=8000001Fh:_Encrypted_Memory_Capabilities
+    uint32_t query_function = 0x8000001F;
+    asm volatile("cpuid"
+	 : "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx)
+	 : "0"(query_function)
+    );
+
+    bool sev_support = (eax & (1<<1)) != 0;
+    bool sev_es_support = (eax & (1<<3)) != 0;
+    bool sev_snp_support = (eax & (1<<4)) != 0;
+
+    uint8_t cbitpos = ebx & 0x3f;
+    uint8_t reduced_phys_bits = (ebx >> 6) & 0x3f;
+
+    const char *path = "/run/qemu-server/";
+    // Check that the directory exists and create it if it does not.
+    struct stat statbuf;
+    int ret = stat(path, &statbuf);
+    if (ret == 0) {
+	if (!S_ISDIR(statbuf.st_mode)) {
+	    printf("Path %s is not a directory.\n", path);
+	    return 1;
+	}
+    } else if (errno == ENOENT) {
+	if (mkdir(path, 0755) != 0) {
+	    printf("Error creating directory %s: %s\n", path, strerror(errno));
+	    return 1;
+	}
+    } else {
+	printf("Error checking path %s: %s\n", path, strerror(errno));
+	return 1;
+    }
+
+    FILE *file;
+    const char *filename = "/run/qemu-server/host-hw-capabilities.json";
+    file = fopen(filename, "w");
+    if (file == NULL) {
+	perror("Error opening file");
+	return 1;
+    }
+
+    ret = fprintf(file,
+	"{"
+	" \"amd-sev\": {"
+	" \"cbitpos\": %u,"
+	" \"reduced-phys-bits\": %u,"
+	" \"sev-support\": %s,"
+	" \"sev-support-es\": %s,"
+	" \"sev-support-snp\": %s"
+	" }"
+	" }\n",
+	cbitpos,
+	reduced_phys_bits,
+	sev_support ? "true" : "false",
+	sev_es_support ? "true" : "false",
+	sev_snp_support ? "true" : "false"
+    );
+    if (ret < 0) {
+	printf("Error writing to file %s: %s\n", path, strerror(errno));
+    }
+
+    ret = fclose(file);
+    if (ret != 0) {
+	printf("Error closing file %s: %s\n", path, strerror(errno));
+    }
+
+    return 0;
+}
-- 
2.39.5



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[pve-devel] [PATCH qemu-server v12 3/6] config: add AMD SEV support

[Markus Frank]

This patch is for enabling AMD SEV (Secure Encrypted Virtualization)
support in QEMU.

VM-Config-Examples:
amd_sev: type=std,no-debug=1,no-key-sharing=1
amd_sev: es,no-debug=1,kernel-hashes=1

kernel-hashes, reduced-phys-bits & cbitpos correspond to the variables
with the same name in QEMU.

kernel-hashes=1 adds kernel hashes to enable measured linux kernel
launch since it is per default off for backward compatibility.

reduced-phys-bios and cbitpos are system specific and are read out by
the query-machine-capabilities c program and saved to the
/run/qemu-server/host-hw-capabilities.json file. This file is parsed
and than used by qemu-server to correctly start a AMD SEV VM.

type=std stands for standard sev to differentiate it from sev-es (es)
or sev-snp (snp) when support is upstream.

QEMU's sev-guest policy gets calculated with the parameters no-debug
& no-key-sharing. These parameters correspond to policy-bits 0 & 1.
If type is 'es' than policy-bit 2 gets set to 1 to activate SEV-ES.
Policy bit 3 (nosend) is always set to 1, because migration features
for sev are not upstream yet and are attackable.

SEV-ES is highly experimental since it could not be tested.

see coherent doc patch

Signed-off-by: Markus Frank <m.frank@proxmox.com>
Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
---
changes v12:
* a eval for decode_json()
* get_amd_sev_object: use the three properties as parameters instead of
 the whole config
* removed efidisk check, as it is obsolete
* small perl style changes

 PVE/QemuServer.pm           | 13 +++++-
 PVE/QemuServer/CPUConfig.pm | 88 ++++++++++++++++++++++++++++++++++++-
 2 files changed, 99 insertions(+), 2 deletions(-)

diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
index 0df3bda0..dd6ae93f 100644
--- a/PVE/QemuServer.pm
+++ b/PVE/QemuServer.pm
@@ -53,7 +53,7 @@ use PVE::QemuConfig;
 use PVE::QemuServer::Helpers qw(config_aware_timeout min_version windows_version);
 use PVE::QemuServer::Cloudinit;
 use PVE::QemuServer::CGroup;
-use PVE::QemuServer::CPUConfig qw(print_cpu_device get_cpu_options get_cpu_bitness is_native_arch);
+use PVE::QemuServer::CPUConfig qw(print_cpu_device get_cpu_options get_cpu_bitness is_native_arch get_amd_sev_object);
 use PVE::QemuServer::Drive qw(is_valid_drivename drive_is_cloudinit drive_is_cdrom drive_is_read_only parse_drive print_drive);
 use PVE::QemuServer::Machine;
 use PVE::QemuServer::Memory qw(get_current_memory);
@@ -358,6 +358,12 @@ my $confdesc = {
 	description => "Memory properties.",
 	format => $PVE::QemuServer::Memory::memory_fmt
     },
+    amd_sev => {
+	description => "Secure Encrypted Virtualization (SEV) features by AMD CPUs",
+	optional => 1,
+	format => 'pve-qemu-sev-fmt',
+	type => 'string',
+    },
     balloon => {
 	optional => 1,
 	type => 'integer',
@@ -4159,6 +4165,11 @@ sub config_to_command {
 	}
     }
 
+    if ($conf->{amd_sev}) {
+	push @$devices, '-object', get_amd_sev_object($conf->{amd_sev}, $conf->{bios}, $conf->{efidisk0});
+	push @$machineFlags, 'confidential-guest-support=sev0';
+    }
+
     push @$cmd, @$devices;
     push @$cmd, '-rtc', join(',', @$rtcFlags) if scalar(@$rtcFlags);
     push @$cmd, '-machine', join(',', @$machineFlags) if scalar(@$machineFlags);
diff --git a/PVE/QemuServer/CPUConfig.pm b/PVE/QemuServer/CPUConfig.pm
index 33f7524f..5110b37e 100644
--- a/PVE/QemuServer/CPUConfig.pm
+++ b/PVE/QemuServer/CPUConfig.pm
@@ -3,9 +3,11 @@ package PVE::QemuServer::CPUConfig;
 use strict;
 use warnings;
 
+use JSON;
+
 use PVE::JSONSchema;
 use PVE::Cluster qw(cfs_register_file cfs_read_file);
-use PVE::Tools qw(get_host_arch);
+use PVE::Tools qw(run_command get_host_arch);
 use PVE::QemuServer::Helpers qw(min_version);
 
 use base qw(PVE::SectionConfig Exporter);
@@ -15,6 +17,7 @@ print_cpu_device
 get_cpu_options
 get_cpu_bitness
 is_native_arch
+get_amd_sev_object
 );
 
 # under certain race-conditions, this module might be loaded before pve-cluster
@@ -225,6 +228,37 @@ my $cpu_fmt = {
     },
 };
 
+my $sev_fmt = {
+    type => {
+	description => "Enable standard SEV with type='std' or enable"
+	    ." experimental SEV-ES with the 'es' option.",
+	type => 'string',
+	default_key => 1,
+	format_description => "sev-type",
+	enum => ['std', 'es'],
+	maxLength => 3,
+    },
+    'no-debug' => {
+	description => "Sets policy bit 0 to 1 to disallow debugging of guest",
+	type => 'boolean',
+	default => 0,
+	optional => 1,
+    },
+    'no-key-sharing' => {
+	description => "Sets policy bit 1 to 1 to disallow key sharing with other guests",
+	type => 'boolean',
+	default => 0,
+	optional => 1,
+    },
+    "kernel-hashes" => {
+	description => "Add kernel hashes to guest firmware for measured linux kernel launch",
+	type => 'boolean',
+	default => 0,
+	optional => 1,
+    },
+};
+PVE::JSONSchema::register_format('pve-qemu-sev-fmt', $sev_fmt);
+
 PVE::JSONSchema::register_format('pve-phys-bits', \&parse_phys_bits);
 sub parse_phys_bits {
     my ($str, $noerr) = @_;
@@ -773,6 +807,58 @@ sub get_cpu_bitness {
     die "unsupported architecture '$arch'\n";
 }
 
+sub get_hw_capabilities {
+    # Get reduced-phys-bits & cbitpos from host-hw-capabilities.json
+    my $filename = '/run/qemu-server/host-hw-capabilities.json';
+    if (! -e $filename) {
+       run_command("/usr/libexec/qemu-server/query-machine-capabilities");
+    }
+    my $json_text = PVE::Tools::file_get_contents($filename);
+    ($json_text) = $json_text =~ /(.*)/; # untaint json text
+    my $hw_capabilities;
+    eval {
+	$hw_capabilities = decode_json($json_text);
+    };
+    if (my $err = $@) {
+	die $err;
+    }
+    return $hw_capabilities;
+}
+
+sub get_amd_sev_object {
+    my ($amd_sev, $bios, $efidisk0) = @_;
+
+    my $amd_sev_conf = PVE::JSONSchema::parse_property_string($sev_fmt, $amd_sev);
+    my $sev_hw_caps = get_hw_capabilities()->{'amd-sev'};
+
+    if (!$sev_hw_caps->{'sev-support'}) {
+	die "Your CPU does not support AMD SEV.\n";
+    }
+    if ($amd_sev_conf->{type} eq 'es' && !$sev_hw_caps->{'sev-support-es'}) {
+	die "Your CPU does not support AMD SEV-ES.\n";
+    }
+    if (!$bios || ($bios && $bios ne 'ovmf')) {
+	die "To use AMD SEV, you need to change the BIOS to OVMF.\n";
+    }
+
+    my $sev_mem_object = 'sev-guest,id=sev0';
+    $sev_mem_object .= ',cbitpos='.$sev_hw_caps->{cbitpos};
+    $sev_mem_object .= ',reduced-phys-bits='.$sev_hw_caps->{'reduced-phys-bits'};
+
+    # guest policy bit calculation as described here:
+    # https://documentation.suse.com/sles/15-SP5/html/SLES-amd-sev/article-amd-sev.html#table-guestpolicy
+    my $policy = 0b0000;
+    $policy += 0b0001 if $amd_sev_conf->{'no-debug'};
+    $policy += 0b0010 if $amd_sev_conf->{'no-key-sharing'};
+    $policy += 0b0100 if $amd_sev_conf->{type} eq 'es';
+    # disable migration with bit 3 nosend to prevent amd-sev-migration-attack
+    $policy += 0b1000;
+
+    $sev_mem_object .= ',policy='.sprintf("%#x", $policy);
+    $sev_mem_object .= ',kernel-hashes=on' if ($amd_sev_conf->{'kernel-hashes'});
+    return $sev_mem_object;
+}
+
 __PACKAGE__->register();
 __PACKAGE__->init();
 
-- 
2.39.5



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[pve-devel] [PATCH qemu-server v12 4/6] migration: add check_non_migratable_resources function

[Markus Frank]

The function checks for resources that cannot be migrated, snapshoted,
or suspended.

To run this function while the snapshot lock is active, the
pve-guest-common patch 'AbstractConfig: add abstract method to check for
resources preventing a snapshot.' is required.

Signed-off-by: Markus Frank <m.frank@proxmox.com>
---
changes v12:
* added overwrite of abstract method __snapshot_assert_no_blockers in
 QemuConfig
* renamed non_migr_res to blockers and non_migratable_resources

 PVE/API2/Qemu.pm   |  5 ++++-
 PVE/QemuConfig.pm  |  5 +++++
 PVE/QemuMigrate.pm |  2 +-
 PVE/QemuServer.pm  | 23 ++++++++++++++++++++++-
 4 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/PVE/API2/Qemu.pm b/PVE/API2/Qemu.pm
index 848001b6..d16b8baa 100644
--- a/PVE/API2/Qemu.pm
+++ b/PVE/API2/Qemu.pm
@@ -4531,7 +4531,7 @@ __PACKAGE__->register_method({
 	$res->{running} = PVE::QemuServer::check_running($vmid) ? 1:0;
 
 	my ($local_resources, $mapped_resources, $missing_mappings_by_node) =
-	    PVE::QemuServer::check_local_resources($vmconf, 1);
+	    PVE::QemuServer::check_local_resources($vmconf, $res->{running}, 1);
 	delete $missing_mappings_by_node->{$localnode};
 
 	my $vga = PVE::QemuServer::parse_vga($vmconf->{vga});
@@ -5219,6 +5219,9 @@ __PACKAGE__->register_method({
 	die "unable to use snapshot name 'pending' (reserved name)\n"
 	    if lc($snapname) eq 'pending';
 
+	my $vmconf = PVE::QemuConfig->load_config($vmid);
+	PVE::QemuServer::check_non_migratable_resources($vmconf, $param->{vmstate}, 0);
+
 	my $realcmd = sub {
 	    PVE::Cluster::log_msg('info', $authuser, "snapshot VM $vmid: $snapname");
 	    PVE::QemuConfig->snapshot_create($vmid, $snapname, $param->{vmstate},
diff --git a/PVE/QemuConfig.pm b/PVE/QemuConfig.pm
index 8e8a7828..ffdf9f03 100644
--- a/PVE/QemuConfig.pm
+++ b/PVE/QemuConfig.pm
@@ -199,6 +199,11 @@ sub get_backup_volumes {
     return $return_volumes;
 }
 
+sub __snapshot_assert_no_blockers {
+    my ($class, $vmconf, $save_vmstate) = @_;
+    PVE::QemuServer::check_non_migratable_resources($vmconf, $save_vmstate, 0);
+}
+
 sub __snapshot_save_vmstate {
     my ($class, $vmid, $conf, $snapname, $storecfg, $statestorage, $suspend) = @_;
 
diff --git a/PVE/QemuMigrate.pm b/PVE/QemuMigrate.pm
index 6591f3f7..09e97268 100644
--- a/PVE/QemuMigrate.pm
+++ b/PVE/QemuMigrate.pm
@@ -233,7 +233,7 @@ sub prepare {
 	$self->{vm_was_paused} = 1 if PVE::QemuServer::vm_is_paused($vmid, 0);
     }
 
-    my ($loc_res, $mapped_res, $missing_mappings_by_node) = PVE::QemuServer::check_local_resources($conf, 1);
+    my ($loc_res, $mapped_res, $missing_mappings_by_node) = PVE::QemuServer::check_local_resources($conf, $running, 1);
     my $blocking_resources = [];
     for my $res ($loc_res->@*) {
 	if (!grep($res, $mapped_res->@*)) {
diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
index dd6ae93f..e94f6d0d 100644
--- a/PVE/QemuServer.pm
+++ b/PVE/QemuServer.pm
@@ -2563,13 +2563,32 @@ sub config_list {
     return $res;
 }
 
+sub check_non_migratable_resources {
+    my ($conf, $state, $noerr) = @_;
+
+    my @blockers = ();
+    if ($state && $conf->{amd_sev}) {
+	push @blockers, "amd_sev";
+    }
+
+    if (scalar(@blockers) && !$noerr) {
+	die "Cannot live-migrate, snapshot (with RAM), or hibernate a VM with:"
+	    ." @blockers\n";
+    }
+
+    return @blockers;
+}
+
 # test if VM uses local resources (to prevent migration)
 sub check_local_resources {
-    my ($conf, $noerr) = @_;
+    my ($conf, $state, $noerr) = @_;
 
     my @loc_res = ();
     my $mapped_res = [];
 
+    my @non_migratable_resources = check_non_migratable_resources($conf, $state, $noerr);
+    push(@loc_res, @non_migratable_resources);
+
     my $nodelist = PVE::Cluster::get_nodelist();
     my $pci_map = PVE::Mapping::PCI::config();
     my $usb_map = PVE::Mapping::USB::config();
@@ -6445,6 +6464,8 @@ sub vm_suspend {
 	die "cannot suspend to disk during backup\n"
 	    if $is_backing_up && $includestate;
 
+	check_non_migratable_resources($conf, $includestate, 0);
+
 	if ($includestate) {
 	    $conf->{lock} = 'suspending';
 	    my $date = strftime("%Y-%m-%d", localtime(time()));
-- 
2.39.5



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[pve-devel] [PATCH docs v12 5/6] add AMD SEV documentation

[Markus Frank]

add documentation for the "[PATCH qemu-server] config: QEMU AMD SEV
enable" patch.

Signed-off-by: Markus Frank <m.frank@proxmox.com>
---
changes v12:
* nothing changed

 qm.adoc | 103 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 103 insertions(+)

diff --git a/qm.adoc b/qm.adoc
index b550888..83bb20b 100644
--- a/qm.adoc
+++ b/qm.adoc
@@ -715,6 +715,109 @@ systems.
 When allocating RAM to your VMs, a good rule of thumb is always to leave 1GB
 of RAM available to the host.
 
+[[qm_memory_encryption]]
+Memory Encryption
+~~~~~~~~~~~~~~~~~
+
+[[qm_memory_encryption_sev]]
+AMD SEV
+^^^^^^^
+
+SEV (Secure Encrypted Virtualization) enables memory encryption per VM using
+AES-128 encryption and the AMD Secure Processor.
+
+SEV-ES (Secure Encrypted Virtualization-Encrypted State) in addition encrypts
+all CPU register contents when a VM stops running, to prevent leakage of
+information to the hypervisor. This feature is very experimental.
+
+*Host Requirements:*
+
+* AMD EPYC CPU
+* SEV-ES is only supported on AMD EPYC 7xx2 and newer
+* configure AMD memory encryption in the BIOS settings of the host machine
+* add "kvm_amd.sev=1" to kernel parameters if not enabled by default
+* add "mem_encrypt=on" to kernel parameters if you want to encrypt memory on the
+host (SME) see https://www.kernel.org/doc/Documentation/x86/amd-memory-encryption.txt
+* maybe increase SWIOTLB see https://github.com/AMDESE/AMDSEV#faq-4
+
+To check if SEV is enabled on the host search for `sev` in dmesg and print out
+the SEV kernel parameter of kvm_amd:
+
+----
+# dmesg | grep -i sev
+[...] ccp 0000:45:00.1: sev enabled
+[...] ccp 0000:45:00.1: SEV API: <buildversion>
+[...] SEV supported: <number> ASIDs
+[...] SEV-ES supported: <number> ASIDs
+# cat /sys/module/kvm_amd/parameters/sev
+Y
+----
+
+*Guest Requirements:*
+
+* edk2-OVMF
+* advisable to use Q35
+* The guest operating system must contain SEV-support.
+
+*Limitations:*
+
+* Because the memory is encrypted the memory usage on host is always wrong.
+* Operations that involve saving or restoring memory like snapshots
+& live migration do not work yet or are attackable.
+https://github.com/PSPReverse/amd-sev-migration-attack
+* PCI passthrough is not supported.
+* SEV-ES is very experimental.
+* QEMU & AMD-SEV documentation is very limited.
+
+Example Configuration:
+
+----
+# qm set <vmid> -amd_sev type=std,no-debug=1,no-key-sharing=1,kernel-hashes=1
+----
+
+The *type* defines the encryption technology ("type=" is not necessary).
+Available options are std & es.
+
+The QEMU *policy* parameter gets calculated with the *no-debug* and
+*no-key-sharing* parameters. These parameters correspond to policy-bit 0 and 1.
+If *type* is *es* the policy-bit 2 is set to 1 so that SEV-ES is enabled.
+Policy-bit 3 (nosend) is always set to 1 to prevent migration-attacks. For more
+information on how to calculate the policy see:
+https://www.amd.com/system/files/TechDocs/55766_SEV-KM_API_Specification.pdf[AMD SEV API Specification Chapter 3]
+
+The *kernel-hashes* is per default off for backward compatibility with older
+OVMF images and guests that do not measure the kernel/initrd.
+See https://lists.gnu.org/archive/html/qemu-devel/2021-11/msg02598.html
+
+*Check if SEV is working on the guest*
+
+Method 1 - dmesg:
+
+Output should look like this.
+
+----
+# dmesg | grep -i sev
+AMD Memory Encryption Features active: SEV
+----
+
+Method 2 - MSR 0xc0010131 (MSR_AMD64_SEV):
+
+Output should be 1.
+
+----
+# apt install msr-tools
+# modprobe msr
+# rdmsr -a 0xc0010131
+1
+----
+
+Links:
+
+* https://developer.amd.com/sev/
+* https://github.com/AMDESE/AMDSEV
+* https://www.qemu.org/docs/master/system/i386/amd-memory-encryption.html
+* https://www.amd.com/system/files/TechDocs/55766_SEV-KM_API_Specification.pdf
+* https://documentation.suse.com/sles/15-SP1/html/SLES-amd-sev/index.html
 
 [[qm_network_device]]
 Network Device
-- 
2.39.5



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[pve-devel] [PATCH manager v12 6/6] ui: add AMD SEV configuration to Options

[Markus Frank]

By adding a new input panel with an AMD SEV technology selection combo
box and checkboxes for the optional parameters in an advanced section,
the user can configure the amd_sev option via the WebUI's Options tab.

Signed-off-by: Markus Frank <m.frank@proxmox.com>
---
changes v12:
* nothing changed

 www/manager6/Makefile        |   1 +
 www/manager6/qemu/Options.js |  11 ++++
 www/manager6/qemu/SevEdit.js | 121 +++++++++++++++++++++++++++++++++++
 3 files changed, 133 insertions(+)
 create mode 100644 www/manager6/qemu/SevEdit.js

diff --git a/www/manager6/Makefile b/www/manager6/Makefile
index 2c3a822b..801683a3 100644
--- a/www/manager6/Makefile
+++ b/www/manager6/Makefile
@@ -264,6 +264,7 @@ JSSRC= 							\
 	qemu/SSHKey.js					\
 	qemu/ScsiHwEdit.js				\
 	qemu/SerialEdit.js				\
+	qemu/SevEdit.js					\
 	qemu/Smbios1Edit.js				\
 	qemu/SystemEdit.js				\
 	qemu/USBEdit.js					\
diff --git a/www/manager6/qemu/Options.js b/www/manager6/qemu/Options.js
index 7b112400..6907699c 100644
--- a/www/manager6/qemu/Options.js
+++ b/www/manager6/qemu/Options.js
@@ -338,6 +338,17 @@ Ext.define('PVE.qemu.Options', {
 		    },
 		} : undefined,
 	    },
+	    amd_sev: {
+		header: gettext('AMD SEV'),
+		editor: caps.vms['VM.Config.HWType'] ? 'PVE.qemu.SevEdit' : undefined,
+		defaultValue: Proxmox.Utils.defaultText + ' (' + Proxmox.Utils.disabledText + ')',
+		renderer: function(value, metaData, record, ri, ci, store, pending) {
+		    let amd_sev = PVE.Parser.parsePropertyString(value, "type");
+		    if (amd_sev.type === 'std') return 'AMD SEV (' + value + ')';
+		    if (amd_sev.type === 'es') return 'AMD SEV-ES (' + value + ')';
+		    return value;
+		},
+	    },
 	    hookscript: {
 		header: gettext('Hookscript'),
 	    },
diff --git a/www/manager6/qemu/SevEdit.js b/www/manager6/qemu/SevEdit.js
new file mode 100644
index 00000000..db7ff3a8
--- /dev/null
+++ b/www/manager6/qemu/SevEdit.js
@@ -0,0 +1,121 @@
+Ext.define('PVE.qemu.SevInputPanel', {
+    extend: 'Proxmox.panel.InputPanel',
+    xtype: 'pveSevInputPanel',
+    onlineHelp: 'qm_memory_encryption',
+
+    viewModel: {
+	data: {
+	    type: '__default__',
+	},
+	formulas: {
+	    sevEnabled: get => get('type') !== '__default__',
+	},
+    },
+
+    onGetValues: function(values) {
+	if (values.delete === 'type') {
+	    values.delete = 'amd_sev';
+	    return values;
+	}
+	if (!values.debug) {
+	    values["no-debug"] = 1;
+	}
+	if (!values["key-sharing"]) {
+	    values["no-key-sharing"] = 1;
+	}
+	delete values.debug;
+	delete values["key-sharing"];
+	let ret = {};
+	ret.amd_sev = PVE.Parser.printPropertyString(values, 'type');
+	return ret;
+    },
+
+
+    setValues: function(values) {
+	if (PVE.Parser.parseBoolean(values["no-debug"])) {
+	    values.debug = 0;
+	}
+	if (PVE.Parser.parseBoolean(values["no-key-sharing"])) {
+	    values["key-sharing"] = 0;
+	}
+	this.callParent(arguments);
+    },
+
+    items: {
+	xtype: 'proxmoxKVComboBox',
+	fieldLabel: gettext('AMD Secure Encrypted Virtualization (SEV)'),
+	labelWidth: 150,
+	name: 'type',
+	value: '__default__',
+	comboItems: [
+	    ['__default__', Proxmox.Utils.defaultText + ' (' + Proxmox.Utils.disabledText + ')'],
+	    ['std', 'AMD SEV'],
+	    ['es', 'AMD SEV-ES (highly experimental)'],
+	],
+	bind: {
+	    value: '{type}',
+	},
+    },
+
+    advancedItems: [
+	{
+	    xtype: 'proxmoxcheckbox',
+	    fieldLabel: gettext('Allow Debugging'),
+	    labelWidth: 150,
+	    name: 'debug',
+	    value: 1,
+	    bind: {
+		hidden: '{!sevEnabled}',
+		disabled: '{!sevEnabled}',
+	    },
+	},
+	{
+	    xtype: 'proxmoxcheckbox',
+	    fieldLabel: gettext('Allow Key-Sharing'),
+	    labelWidth: 150,
+	    name: 'key-sharing',
+	    value: 1,
+	    bind: {
+		hidden: '{!sevEnabled}',
+		disabled: '{!sevEnabled}',
+	    },
+	},
+	{
+	    xtype: 'proxmoxcheckbox',
+	    fieldLabel: gettext('Enable Kernel Hashes'),
+	    labelWidth: 150,
+	    name: 'kernel-hashes',
+	    deleteDefaultValue: false,
+	    bind: {
+		hidden: '{!sevEnabled}',
+		disabled: '{!sevEnabled}',
+	    },
+	},
+    ],
+});
+
+Ext.define('PVE.qemu.SevEdit', {
+    extend: 'Proxmox.window.Edit',
+
+    subject: gettext('SEV'),
+
+    items: {
+	xtype: 'pveSevInputPanel',
+    },
+
+    width: 400,
+
+    initComponent: function() {
+	let me = this;
+
+	me.callParent();
+
+	me.load({
+	    success: function(response) {
+		let conf = response.result.data;
+		let amd_sev = conf.amd_sev || '__default__';
+		me.setValues(PVE.Parser.parsePropertyString(amd_sev, 'type'));
+	    },
+	});
+    },
+});
-- 
2.39.5



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[pve-devel] applied: [PATCH guest-common v12 1/6] AbstractConfig: add abstract method to check for resources preventing a snapshot

[Thomas Lamprecht]

Am 11.11.24 um 14:57 schrieb Markus Frank:
> Signed-off-by: Markus Frank <m.frank@proxmox.com>
> Suggested-by: Fiona Ebner <f.ebner@proxmox.com>
> ---
> This patch is new in v12.
> 
>  src/PVE/AbstractConfig.pm | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
>

applied, thanks!


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[pve-devel] applied: [PATCH qemu-server v12 2/6] add C program to get hardware capabilities from CPUID

[Thomas Lamprecht]

Am 11.11.24 um 14:57 schrieb Markus Frank:
> Implement a C program that extracts AMD SEV hardware information such
> as reduced-phys-bios and cbitpos from CPUID, looks if SEV, SEV-ES &
> SEV-SNP are enabled, and outputs these details as JSON to
> /run/qemu-server/host-hw-capabilities.json
> 
> This program can also be used to read and save other hardware
> information.
> 
> Signed-off-by: Markus Frank <m.frank@proxmox.com>
> Co-authored-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
> Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
> ---
> changes v12:
> * improved error handling
> 
>  Makefile                                      |  1 +
>  query-machine-capabilities/Makefile           | 18 +++++
>  .../query-machine-capabilities.c              | 79 +++++++++++++++++++
>  3 files changed, 98 insertions(+)
>  create mode 100644 query-machine-capabilities/Makefile
>  create mode 100644 query-machine-capabilities/query-machine-capabilities.c
> 
>

applied, thanks!

how will this be called again? just because I forgot and do not see any
systemd unit file here.


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Re: [pve-devel] [PATCH qemu-server v12 3/6] config: add AMD SEV support

[Thomas Lamprecht]

Am 11.11.24 um 14:57 schrieb Markus Frank:
> This patch is for enabling AMD SEV (Secure Encrypted Virtualization)
> support in QEMU.
> 
> VM-Config-Examples:
> amd_sev: type=std,no-debug=1,no-key-sharing=1
> amd_sev: es,no-debug=1,kernel-hashes=1
> 
> kernel-hashes, reduced-phys-bits & cbitpos correspond to the variables
> with the same name in QEMU.
> 
> kernel-hashes=1 adds kernel hashes to enable measured linux kernel
> launch since it is per default off for backward compatibility.
> 
> reduced-phys-bios and cbitpos are system specific and are read out by
> the query-machine-capabilities c program and saved to the
> /run/qemu-server/host-hw-capabilities.json file. This file is parsed
> and than used by qemu-server to correctly start a AMD SEV VM.
> 
> type=std stands for standard sev to differentiate it from sev-es (es)
> or sev-snp (snp) when support is upstream.
> 
> QEMU's sev-guest policy gets calculated with the parameters no-debug
> & no-key-sharing. These parameters correspond to policy-bits 0 & 1.
> If type is 'es' than policy-bit 2 gets set to 1 to activate SEV-ES.
> Policy bit 3 (nosend) is always set to 1, because migration features
> for sev are not upstream yet and are attackable.
> 
> SEV-ES is highly experimental since it could not be tested.
> 
> see coherent doc patch

looks mostly OK some more minor stuff inline

> 
> Signed-off-by: Markus Frank <m.frank@proxmox.com>
> Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
> ---
> changes v12:
> * a eval for decode_json()
> * get_amd_sev_object: use the three properties as parameters instead of
>  the whole config
> * removed efidisk check, as it is obsolete
> * small perl style changes
> 
>  PVE/QemuServer.pm           | 13 +++++-
>  PVE/QemuServer/CPUConfig.pm | 88 ++++++++++++++++++++++++++++++++++++-
>  2 files changed, 99 insertions(+), 2 deletions(-)
> 
> diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
> index 0df3bda0..dd6ae93f 100644
> --- a/PVE/QemuServer.pm
> +++ b/PVE/QemuServer.pm
> @@ -53,7 +53,7 @@ use PVE::QemuConfig;
>  use PVE::QemuServer::Helpers qw(config_aware_timeout min_version windows_version);
>  use PVE::QemuServer::Cloudinit;
>  use PVE::QemuServer::CGroup;
> -use PVE::QemuServer::CPUConfig qw(print_cpu_device get_cpu_options get_cpu_bitness is_native_arch);
> +use PVE::QemuServer::CPUConfig qw(print_cpu_device get_cpu_options get_cpu_bitness is_native_arch get_amd_sev_object);
>  use PVE::QemuServer::Drive qw(is_valid_drivename drive_is_cloudinit drive_is_cdrom drive_is_read_only parse_drive print_drive);
>  use PVE::QemuServer::Machine;
>  use PVE::QemuServer::Memory qw(get_current_memory);
> @@ -358,6 +358,12 @@ my $confdesc = {
>  	description => "Memory properties.",
>  	format => $PVE::QemuServer::Memory::memory_fmt
>      },
> +    amd_sev => {

as of now this can be named 'amd-sev' 

> +	description => "Secure Encrypted Virtualization (SEV) features by AMD CPUs",
> +	optional => 1,
> +	format => 'pve-qemu-sev-fmt',
> +	type => 'string',
> +    },
>      balloon => {
>  	optional => 1,
>  	type => 'integer',
> @@ -4159,6 +4165,11 @@ sub config_to_command {
>  	}
>      }
>  
> +    if ($conf->{amd_sev}) {
> +	push @$devices, '-object', get_amd_sev_object($conf->{amd_sev}, $conf->{bios}, $conf->{efidisk0});
> +	push @$machineFlags, 'confidential-guest-support=sev0';
> +    }
> +
>      push @$cmd, @$devices;
>      push @$cmd, '-rtc', join(',', @$rtcFlags) if scalar(@$rtcFlags);
>      push @$cmd, '-machine', join(',', @$machineFlags) if scalar(@$machineFlags);
> diff --git a/PVE/QemuServer/CPUConfig.pm b/PVE/QemuServer/CPUConfig.pm
> index 33f7524f..5110b37e 100644
> --- a/PVE/QemuServer/CPUConfig.pm
> +++ b/PVE/QemuServer/CPUConfig.pm
> @@ -3,9 +3,11 @@ package PVE::QemuServer::CPUConfig;
>  use strict;
>  use warnings;
>  
> +use JSON;
> +
>  use PVE::JSONSchema;
>  use PVE::Cluster qw(cfs_register_file cfs_read_file);
> -use PVE::Tools qw(get_host_arch);
> +use PVE::Tools qw(run_command get_host_arch);
>  use PVE::QemuServer::Helpers qw(min_version);
>  
>  use base qw(PVE::SectionConfig Exporter);
> @@ -15,6 +17,7 @@ print_cpu_device
>  get_cpu_options
>  get_cpu_bitness
>  is_native_arch
> +get_amd_sev_object
>  );
>  
>  # under certain race-conditions, this module might be loaded before pve-cluster
> @@ -225,6 +228,37 @@ my $cpu_fmt = {
>      },
>  };
>  
> +my $sev_fmt = {
> +    type => {
> +	description => "Enable standard SEV with type='std' or enable"
> +	    ." experimental SEV-ES with the 'es' option.",
> +	type => 'string',
> +	default_key => 1,
> +	format_description => "sev-type",
> +	enum => ['std', 'es'],
> +	maxLength => 3,
> +    },
> +    'no-debug' => {
> +	description => "Sets policy bit 0 to 1 to disallow debugging of guest",
> +	type => 'boolean',
> +	default => 0,
> +	optional => 1,
> +    },
> +    'no-key-sharing' => {
> +	description => "Sets policy bit 1 to 1 to disallow key sharing with other guests",
> +	type => 'boolean',
> +	default => 0,
> +	optional => 1,
> +    },
> +    "kernel-hashes" => {
> +	description => "Add kernel hashes to guest firmware for measured linux kernel launch",
> +	type => 'boolean',
> +	default => 0,
> +	optional => 1,
> +    },
> +};
> +PVE::JSONSchema::register_format('pve-qemu-sev-fmt', $sev_fmt);
> +
>  PVE::JSONSchema::register_format('pve-phys-bits', \&parse_phys_bits);
>  sub parse_phys_bits {
>      my ($str, $noerr) = @_;
> @@ -773,6 +807,58 @@ sub get_cpu_bitness {
>      die "unsupported architecture '$arch'\n";
>  }
>  
> +sub get_hw_capabilities {
> +    # Get reduced-phys-bits & cbitpos from host-hw-capabilities.json
> +    my $filename = '/run/qemu-server/host-hw-capabilities.json';

hmm, rethinking this it might be good to move that to somewhere accessible for non-root,
but can be done also in the future.

> +    if (! -e $filename) {
> +       run_command("/usr/libexec/qemu-server/query-machine-capabilities");

maybe once at boot through a systemd service file could be nicer than this a bit
subtle way.

> +    }
> +    my $json_text = PVE::Tools::file_get_contents($filename);
> +    ($json_text) = $json_text =~ /(.*)/; # untaint json text
> +    my $hw_capabilities;
> +    eval {
> +	$hw_capabilities = decode_json($json_text);
> +    };

can be shortened to:

my $hw_capabilities = eval { decode_json($json_text) };

> +    if (my $err = $@) {
> +	die $err;
> +    }
> +    return $hw_capabilities;
> +}
> +
> +sub get_amd_sev_object {
> +    my ($amd_sev, $bios, $efidisk0) = @_;
> +
> +    my $amd_sev_conf = PVE::JSONSchema::parse_property_string($sev_fmt, $amd_sev);
> +    my $sev_hw_caps = get_hw_capabilities()->{'amd-sev'};
> +
> +    if (!$sev_hw_caps->{'sev-support'}) {
> +	die "Your CPU does not support AMD SEV.\n";
> +    }
> +    if ($amd_sev_conf->{type} eq 'es' && !$sev_hw_caps->{'sev-support-es'}) {
> +	die "Your CPU does not support AMD SEV-ES.\n";
> +    }
> +    if (!$bios || ($bios && $bios ne 'ovmf')) {

In general `!a || (a && b) == !a || b` so above can be shortened to

if (!$bios || $bios ne 'ovmf') {
    # ...




> +	die "To use AMD SEV, you need to change the BIOS to OVMF.\n";
> +    }
> +
> +    my $sev_mem_object = 'sev-guest,id=sev0';
> +    $sev_mem_object .= ',cbitpos='.$sev_hw_caps->{cbitpos};
> +    $sev_mem_object .= ',reduced-phys-bits='.$sev_hw_caps->{'reduced-phys-bits'};
> +
> +    # guest policy bit calculation as described here:
> +    # https://documentation.suse.com/sles/15-SP5/html/SLES-amd-sev/article-amd-sev.html#table-guestpolicy
> +    my $policy = 0b0000;
> +    $policy += 0b0001 if $amd_sev_conf->{'no-debug'};
> +    $policy += 0b0010 if $amd_sev_conf->{'no-key-sharing'};
> +    $policy += 0b0100 if $amd_sev_conf->{type} eq 'es';
> +    # disable migration with bit 3 nosend to prevent amd-sev-migration-attack
> +    $policy += 0b1000;
> +
> +    $sev_mem_object .= ',policy='.sprintf("%#x", $policy);
> +    $sev_mem_object .= ',kernel-hashes=on' if ($amd_sev_conf->{'kernel-hashes'});
> +    return $sev_mem_object;
> +}
> +
>  __PACKAGE__->register();
>  __PACKAGE__->init();
>  



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