The Realm Personalization Value (RPV) is provided by the user to
distinguish Realms that have the same initial measurement.
The user provides a 512-bit hexadecimal number.
Signed-off-by: Jean-Philippe Brucker
---
qapi/qom.json| 5 ++-
target/arm/kvm-rme.c | 72 +++-
2 files changed, 75 insertions(+), 2 deletions(-)
diff --git a/qapi/qom.json b/qapi/qom.json
index 87fe7c31fe..a012281628 100644
--- a/qapi/qom.json
+++ b/qapi/qom.json
@@ -862,10 +862,13 @@
#
# @measurement-algo: Realm measurement algorithm (default: RMM default)
#
+# @personalization-value: Realm personalization value (default: 0)
+#
# Since: FIXME
##
{ 'struct': 'RmeGuestProperties',
- 'data': { '*measurement-algo': 'str' } }
+ 'data': { '*measurement-algo': 'str',
+'*personalization-value': 'str' } }
##
# @ObjectType:
diff --git a/target/arm/kvm-rme.c b/target/arm/kvm-rme.c
index 3929b941ae..e974c27e5c 100644
--- a/target/arm/kvm-rme.c
+++ b/target/arm/kvm-rme.c
@@ -22,13 +22,14 @@ OBJECT_DECLARE_SIMPLE_TYPE(RmeGuest, RME_GUEST)
#define RME_PAGE_SIZE qemu_real_host_page_size()
-#define RME_MAX_CFG 1
+#define RME_MAX_CFG 2
typedef struct RmeGuest RmeGuest;
struct RmeGuest {
ConfidentialGuestSupport parent_obj;
char *measurement_algo;
+char *personalization_value;
};
struct RmeImage {
@@ -65,6 +66,45 @@ static int rme_create_rd(RmeGuest *guest, Error **errp)
return ret;
}
+static int rme_parse_rpv(uint8_t *out, const char *in, Error **errp)
+{
+int ret;
+size_t in_len = strlen(in);
+
+/* Two chars per byte */
+if (in_len > KVM_CAP_ARM_RME_RPV_SIZE * 2) {
+error_setg(errp, "Realm Personalization Value is too large");
+return -E2BIG;
+}
+
+/*
+ * Parse as big-endian hexadecimal number (most significant byte on the
+ * left), store little-endian, zero-padded on the right.
+ */
+while (in_len) {
+/*
+ * Do the lower nibble first to catch invalid inputs such as '2z', and
+ * to handle the last char.
+ */
+in_len--;
+ret = sscanf(in + in_len, "%1hhx", out);
+if (ret != 1) {
+error_setg(errp, "Invalid Realm Personalization Value");
+return -EINVAL;
+}
+if (!in_len) {
+break;
+}
+in_len--;
+ret = sscanf(in + in_len, "%2hhx", out++);
+if (ret != 1) {
+error_setg(errp, "Invalid Realm Personalization Value");
+return -EINVAL;
+}
+}
+return 0;
+}
+
static int rme_configure_one(RmeGuest *guest, uint32_t cfg, Error **errp)
{
int ret;
@@ -87,6 +127,16 @@ static int rme_configure_one(RmeGuest *guest, uint32_t cfg,
Error **errp)
}
cfg_str = "hash algorithm";
break;
+case KVM_CAP_ARM_RME_CFG_RPV:
+if (!guest->personalization_value) {
+return 0;
+}
+ret = rme_parse_rpv(args.rpv, guest->personalization_value, errp);
+if (ret) {
+return ret;
+}
+cfg_str = "personalization value";
+break;
default:
g_assert_not_reached();
}
@@ -281,6 +331,21 @@ static void rme_set_measurement_algo(Object *obj, const
char *value,
guest->measurement_algo = g_strdup(value);
}
+static char *rme_get_rpv(Object *obj, Error **errp)
+{
+RmeGuest *guest = RME_GUEST(obj);
+
+return g_strdup(guest->personalization_value);
+}
+
+static void rme_set_rpv(Object *obj, const char *value, Error **errp)
+{
+RmeGuest *guest = RME_GUEST(obj);
+
+g_free(guest->personalization_value);
+guest->personalization_value = g_strdup(value);
+}
+
static void rme_guest_class_init(ObjectClass *oc, void *data)
{
object_class_property_add_str(oc, "measurement-algo",
@@ -288,6 +353,11 @@ static void rme_guest_class_init(ObjectClass *oc, void
*data)
rme_set_measurement_algo);
object_class_property_set_description(oc, "measurement-algo",
"Realm measurement algorithm ('sha256', 'sha512')");
+
+object_class_property_add_str(oc, "personalization-value", rme_get_rpv,
+ rme_set_rpv);
+object_class_property_set_description(oc, "personalization-value",
+"Realm personalization value (512-bit hexadecimal number)");
}
static const TypeInfo rme_guest_info = {
--
2.39.0
