[PATCH v4 29/66] i386/tdx: Support user configurable mrconfigid/mrowner/mrownerconfig

[Xiaoyao Li <xiaoyao.li@intel.com>]

From: Isaku Yamahata <isaku.yamahata@intel.com>

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>

---
Changes in v4:
 - describe more of there fields in qom.json
 - free the old value before set new value to avoid memory leak in
   _setter(); (Daniel)

Changes in v3:
 - use base64 encoding instread of hex-string;
---
 qapi/qom.json         | 14 ++++++-
 target/i386/kvm/tdx.c | 87 +++++++++++++++++++++++++++++++++++++++++++
 target/i386/kvm/tdx.h |  3 ++
 3 files changed, 103 insertions(+), 1 deletion(-)

diff --git a/qapi/qom.json b/qapi/qom.json
index 2177f3101382..15445f9e41fc 100644
--- a/qapi/qom.json
+++ b/qapi/qom.json
@@ -905,10 +905,22 @@
 #     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.
+#
+# @mrowner: ID for the guest TD’s owner.  base64 encoded SHA384 digest.
+#
+# @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.
+#
 # Since: 9.0
 ##
 { 'struct': 'TdxGuestProperties',
-  'data': { '*sept-ve-disable': 'bool' } }
+  'data': { '*sept-ve-disable': 'bool',
+            '*mrconfigid': 'str',
+            '*mrowner': 'str',
+            '*mrownerconfig': 'str' } }
 
 ##
 # @ThreadContextProperties:
diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index 8c2bf512397e..ead19923f318 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -13,6 +13,7 @@
 
 #include "qemu/osdep.h"
 #include "qemu/error-report.h"
+#include "qemu/base64.h"
 #include "qapi/error.h"
 #include "qom/object_interfaces.h"
 #include "standard-headers/asm-x86/kvm_para.h"
@@ -515,6 +516,7 @@ int tdx_pre_create_vcpu(CPUState *cpu, Error **errp)
     X86CPU *x86cpu = X86_CPU(cpu);
     CPUX86State *env = &x86cpu->env;
     g_autofree struct kvm_tdx_init_vm *init_vm = NULL;
+    size_t data_len;
     int r = 0;
 
     QEMU_LOCK_GUARD(&tdx_guest->lock);
@@ -525,6 +527,38 @@ 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);
 
+#define SHA384_DIGEST_SIZE  48
+
+    if (tdx_guest->mrconfigid) {
+        g_autofree uint8_t *data = qbase64_decode(tdx_guest->mrconfigid,
+                              strlen(tdx_guest->mrconfigid), &data_len, errp);
+        if (!data || data_len != SHA384_DIGEST_SIZE) {
+            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 || data_len != SHA384_DIGEST_SIZE) {
+            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 || data_len != SHA384_DIGEST_SIZE) {
+            error_setg(errp, "TDX: failed to decode mrownerconfig");
+            return -1;
+        }
+        memcpy(init_vm->mrownerconfig, data, data_len);
+    }
+
     r = kvm_vm_enable_cap(kvm_state, KVM_CAP_MAX_VCPUS, 0, ms->smp.cpus);
     if (r < 0) {
         error_setg(errp, "Unable to set MAX VCPUS to %d", ms->smp.cpus);
@@ -571,6 +605,51 @@ 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,
@@ -590,6 +669,14 @@ 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)
diff --git a/target/i386/kvm/tdx.h b/target/i386/kvm/tdx.h
index 432077723ac5..6e39ef3bac13 100644
--- a/target/i386/kvm/tdx.h
+++ b/target/i386/kvm/tdx.h
@@ -21,6 +21,9 @@ typedef struct TdxGuest {
 
     bool initialized;
     uint64_t attributes;    /* TD attributes */
+    char *mrconfigid;       /* base64 encoded sha348 digest */
+    char *mrowner;          /* base64 encoded sha348 digest */
+    char *mrownerconfig;    /* base64 encoded sha348 digest */
 } TdxGuest;
 
 #ifdef CONFIG_TDX
-- 
2.34.1