i386/tdx: Support user configurable mrconfigid/mrowner/mrownerconfig

Three sha384 hash values, mrconfigid, mrowner and mrownerconfig, of a TD
can be provided for TDX attestation. Detailed meaning of them can be
found: https://lore.kernel.org/qemu-devel/31d6dbc1-f453-4cef-ab08-4813f4e0ff92@intel.com/

Allow user to specify those values via property mrconfigid, mrowner and
mrownerconfig. They are all in base64 format.

example
-object tdx-guest, \
  mrconfigid=ASNFZ4mrze8BI0VniavN7wEjRWeJq83vASNFZ4mrze8BI0VniavN7wEjRWeJq83v,\
  mrowner=ASNFZ4mrze8BI0VniavN7wEjRWeJq83vASNFZ4mrze8BI0VniavN7wEjRWeJq83v,\
  mrownerconfig=ASNFZ4mrze8BI0VniavN7wEjRWeJq83vASNFZ4mrze8BI0VniavN7wEjRWeJq83v

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Co-developed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250508150002.689633-14-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qapi/qom.json

@@ -1060,11 +1060,25 @@
 #     pages.  Some guest OS (e.g., Linux TD guest) may require this to
 #     be set, otherwise they refuse to boot.
 #
+# @mrconfigid: ID for non-owner-defined configuration of the guest TD,
+#     e.g., run-time or OS configuration (base64 encoded SHA384 digest).
+#     Defaults to all zeros.
+#
+# @mrowner: ID for the guest TD’s owner (base64 encoded SHA384 digest).
+#     Defaults to all zeros.
+#
+# @mrownerconfig: ID for owner-defined configuration of the guest TD,
+#     e.g., specific to the workload rather than the run-time or OS
+#     (base64 encoded SHA384 digest).  Defaults to all zeros.
+#
 # Since: 10.1
 ##
 { 'struct': 'TdxGuestProperties',
   'data': { '*attributes': 'uint64',
-            '*sept-ve-disable': 'bool' } }
+            '*sept-ve-disable': 'bool',
+            '*mrconfigid': 'str',
+            '*mrowner': 'str',
+            '*mrownerconfig': 'str' } }
 
 ##
 # @ThreadContextProperties:

target/i386/kvm/tdx.c

@@ -11,8 +11,10 @@
 
 #include "qemu/osdep.h"
 #include "qemu/error-report.h"
+#include "qemu/base64.h"
 #include "qapi/error.h"
 #include "qom/object_interfaces.h"
+#include "crypto/hash.h"
 
 #include "hw/i386/x86.h"
 #include "kvm_i386.h"
@@ -240,6 +242,7 @@ int tdx_pre_create_vcpu(CPUState *cpu, Error **errp)
     CPUX86State *env = &x86cpu->env;
     g_autofree struct kvm_tdx_init_vm *init_vm = NULL;
     Error *local_err = NULL;
+    size_t data_len;
     int retry = 10000;
     int r = 0;
 
@@ -251,6 +254,45 @@ int tdx_pre_create_vcpu(CPUState *cpu, Error **errp)
     init_vm = g_malloc0(sizeof(struct kvm_tdx_init_vm) +
                         sizeof(struct kvm_cpuid_entry2) * KVM_MAX_CPUID_ENTRIES);
 
+    if (tdx_guest->mrconfigid) {
+        g_autofree uint8_t *data = qbase64_decode(tdx_guest->mrconfigid,
+                              strlen(tdx_guest->mrconfigid), &data_len, errp);
+        if (!data) {
+            return -1;
+        }
+        if (data_len != QCRYPTO_HASH_DIGEST_LEN_SHA384) {
+            error_setg(errp, "TDX: failed to decode mrconfigid");
+            return -1;
+        }
+        memcpy(init_vm->mrconfigid, data, data_len);
+    }
+
+    if (tdx_guest->mrowner) {
+        g_autofree uint8_t *data = qbase64_decode(tdx_guest->mrowner,
+                              strlen(tdx_guest->mrowner), &data_len, errp);
+        if (!data) {
+            return -1;
+        }
+        if (data_len != QCRYPTO_HASH_DIGEST_LEN_SHA384) {
+            error_setg(errp, "TDX: failed to decode mrowner");
+            return -1;
+        }
+        memcpy(init_vm->mrowner, data, data_len);
+    }
+
+    if (tdx_guest->mrownerconfig) {
+        g_autofree uint8_t *data = qbase64_decode(tdx_guest->mrownerconfig,
+                            strlen(tdx_guest->mrownerconfig), &data_len, errp);
+        if (!data) {
+            return -1;
+        }
+        if (data_len != QCRYPTO_HASH_DIGEST_LEN_SHA384) {
+            error_setg(errp, "TDX: failed to decode mrownerconfig");
+            return -1;
+        }
+        memcpy(init_vm->mrownerconfig, data, data_len);
+    }
+
     r = setup_td_guest_attributes(x86cpu, errp);
     if (r) {
         return r;
@@ -314,6 +356,51 @@ static void tdx_guest_set_sept_ve_disable(Object *obj, bool value, Error **errp)
     }
 }
 
+static char *tdx_guest_get_mrconfigid(Object *obj, Error **errp)
+{
+    TdxGuest *tdx = TDX_GUEST(obj);
+
+    return g_strdup(tdx->mrconfigid);
+}
+
+static void tdx_guest_set_mrconfigid(Object *obj, const char *value, Error **errp)
+{
+    TdxGuest *tdx = TDX_GUEST(obj);
+
+    g_free(tdx->mrconfigid);
+    tdx->mrconfigid = g_strdup(value);
+}
+
+static char *tdx_guest_get_mrowner(Object *obj, Error **errp)
+{
+    TdxGuest *tdx = TDX_GUEST(obj);
+
+    return g_strdup(tdx->mrowner);
+}
+
+static void tdx_guest_set_mrowner(Object *obj, const char *value, Error **errp)
+{
+    TdxGuest *tdx = TDX_GUEST(obj);
+
+    g_free(tdx->mrowner);
+    tdx->mrowner = g_strdup(value);
+}
+
+static char *tdx_guest_get_mrownerconfig(Object *obj, Error **errp)
+{
+    TdxGuest *tdx = TDX_GUEST(obj);
+
+    return g_strdup(tdx->mrownerconfig);
+}
+
+static void tdx_guest_set_mrownerconfig(Object *obj, const char *value, Error **errp)
+{
+    TdxGuest *tdx = TDX_GUEST(obj);
+
+    g_free(tdx->mrownerconfig);
+    tdx->mrownerconfig = g_strdup(value);
+}
+
 /* tdx guest */
 OBJECT_DEFINE_TYPE_WITH_INTERFACES(TdxGuest,
                                    tdx_guest,
@@ -337,6 +424,14 @@ static void tdx_guest_init(Object *obj)
     object_property_add_bool(obj, "sept-ve-disable",
                              tdx_guest_get_sept_ve_disable,
                              tdx_guest_set_sept_ve_disable);
+    object_property_add_str(obj, "mrconfigid",
+                            tdx_guest_get_mrconfigid,
+                            tdx_guest_set_mrconfigid);
+    object_property_add_str(obj, "mrowner",
+                            tdx_guest_get_mrowner, tdx_guest_set_mrowner);
+    object_property_add_str(obj, "mrownerconfig",
+                            tdx_guest_get_mrownerconfig,
+                            tdx_guest_set_mrownerconfig);
 }
 
 static void tdx_guest_finalize(Object *obj)

target/i386/kvm/tdx.h

@@ -24,6 +24,9 @@ typedef struct TdxGuest {
     bool initialized;
     uint64_t attributes;    /* TD attributes */
     uint64_t xfam;
+    char *mrconfigid;       /* base64 encoded sha348 digest */
+    char *mrowner;          /* base64 encoded sha348 digest */
+    char *mrownerconfig;    /* base64 encoded sha348 digest */
 } TdxGuest;
 
 #ifdef CONFIG_TDX