@@ -172,6 +172,8 @@ typedef enum {
SEV_DESC_TYPE_SNP_SECRETS,
/* The section contains address that can be used as a CPUID page */
SEV_DESC_TYPE_CPUID,
+ /* The section contains the region for kernel hashes for measured direct boot */
+ SEV_DESC_TYPE_SNP_KERNEL_HASHES = 0x10,
} ovmf_sev_metadata_desc_type;
@@ -115,6 +115,10 @@ struct SevCommonStateClass {
X86ConfidentialGuestClass parent_class;
/* public */
+ bool (*build_kernel_loader_hashes)(SevCommonState *sev_common,
+ SevHashTableDescriptor *area,
+ SevKernelLoaderContext *ctx,
+ Error **errp);
int (*launch_start)(SevCommonState *sev_common);
void (*launch_finish)(SevCommonState *sev_common);
int (*launch_update_data)(SevCommonState *sev_common, hwaddr gpa, uint8_t *ptr, uint64_t len);
@@ -154,6 +158,9 @@ struct SevSnpGuestState {
struct kvm_sev_snp_launch_start kvm_start_conf;
struct kvm_sev_snp_launch_finish kvm_finish_conf;
+
+ uint32_t kernel_hashes_offset;
+ PaddedSevHashTable *kernel_hashes_data;
};
#define DEFAULT_GUEST_POLICY 0x1 /* disable debug */
@@ -1189,6 +1196,23 @@ snp_launch_update_cpuid(uint32_t cpuid_addr, void *hva, uint32_t cpuid_len)
KVM_SEV_SNP_PAGE_TYPE_CPUID);
}
+static int
+snp_launch_update_kernel_hashes(SevSnpGuestState *sev_snp, uint32_t addr,
+ void *hva, uint32_t len)
+{
+ int type = KVM_SEV_SNP_PAGE_TYPE_ZERO;
+ if (sev_snp->parent_obj.kernel_hashes) {
+ assert(sev_snp->kernel_hashes_data);
+ assert((sev_snp->kernel_hashes_offset +
+ sizeof(*sev_snp->kernel_hashes_data)) <= len);
+ memset(hva, 0, len);
+ memcpy(hva + sev_snp->kernel_hashes_offset, sev_snp->kernel_hashes_data,
+ sizeof(*sev_snp->kernel_hashes_data));
+ type = KVM_SEV_SNP_PAGE_TYPE_NORMAL;
+ }
+ return snp_launch_update_data(addr, hva, len, type);
+}
+
static int
snp_metadata_desc_to_page_type(int desc_type)
{
@@ -1225,6 +1249,9 @@ snp_populate_metadata_pages(SevSnpGuestState *sev_snp,
if (type == KVM_SEV_SNP_PAGE_TYPE_CPUID) {
ret = snp_launch_update_cpuid(desc->base, hva, desc->len);
+ } else if (desc->type == SEV_DESC_TYPE_SNP_KERNEL_HASHES) {
+ ret = snp_launch_update_kernel_hashes(sev_snp, desc->base, hva,
+ desc->len);
} else {
ret = snp_launch_update_data(desc->base, hva, desc->len, type);
}
@@ -1823,40 +1850,31 @@ static bool build_kernel_loader_hashes(PaddedSevHashTable *padded_ht,
return true;
}
-/*
- * Add the hashes of the linux kernel/initrd/cmdline to an encrypted guest page
- * which is included in SEV's initial memory measurement.
- */
-bool sev_add_kernel_loader_hashes(SevKernelLoaderContext *ctx, Error **errp)
+static bool sev_snp_build_kernel_loader_hashes(SevCommonState *sev_common,
+ SevHashTableDescriptor *area,
+ SevKernelLoaderContext *ctx,
+ Error **errp)
+{
+ /*
+ * SNP: Populate the hashes table in an area that later in
+ * snp_launch_update_kernel_hashes() will be copied to the guest memory
+ * and encrypted.
+ */
+ SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(sev_common);
+ sev_snp_guest->kernel_hashes_offset = area->base & ~TARGET_PAGE_MASK;
+ sev_snp_guest->kernel_hashes_data = g_new0(PaddedSevHashTable, 1);
+ return build_kernel_loader_hashes(sev_snp_guest->kernel_hashes_data, ctx, errp);
+}
+
+static bool sev_build_kernel_loader_hashes(SevCommonState *sev_common,
+ SevHashTableDescriptor *area,
+ SevKernelLoaderContext *ctx,
+ Error **errp)
{
- uint8_t *data;
- SevHashTableDescriptor *area;
PaddedSevHashTable *padded_ht;
hwaddr mapped_len = sizeof(*padded_ht);
MemTxAttrs attrs = { 0 };
bool ret = true;
- SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs);
-
- /*
- * Only add the kernel hashes if the sev-guest configuration explicitly
- * stated kernel-hashes=on.
- */
- if (!sev_common->kernel_hashes) {
- return false;
- }
-
- if (!pc_system_ovmf_table_find(SEV_HASH_TABLE_RV_GUID, &data, NULL)) {
- error_setg(errp, "SEV: kernel specified but guest firmware "
- "has no hashes table GUID");
- return false;
- }
-
- area = (SevHashTableDescriptor *)data;
- if (!area->base || area->size < sizeof(PaddedSevHashTable)) {
- error_setg(errp, "SEV: guest firmware hashes table area is invalid "
- "(base=0x%x size=0x%x)", area->base, area->size);
- return false;
- }
/*
* Populate the hashes table in the guest's memory at the OVMF-designated
@@ -1884,6 +1902,41 @@ bool sev_add_kernel_loader_hashes(SevKernelLoaderContext *ctx, Error **errp)
return ret;
}
+/*
+ * Add the hashes of the linux kernel/initrd/cmdline to an encrypted guest page
+ * which is included in SEV's initial memory measurement.
+ */
+bool sev_add_kernel_loader_hashes(SevKernelLoaderContext *ctx, Error **errp)
+{
+ uint8_t *data;
+ SevHashTableDescriptor *area;
+ SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs);
+ SevCommonStateClass *klass = SEV_COMMON_GET_CLASS(sev_common);
+
+ /*
+ * Only add the kernel hashes if the sev-guest configuration explicitly
+ * stated kernel-hashes=on.
+ */
+ if (!sev_common->kernel_hashes) {
+ return false;
+ }
+
+ if (!pc_system_ovmf_table_find(SEV_HASH_TABLE_RV_GUID, &data, NULL)) {
+ error_setg(errp, "SEV: kernel specified but guest firmware "
+ "has no hashes table GUID");
+ return false;
+ }
+
+ area = (SevHashTableDescriptor *)data;
+ if (!area->base || area->size < sizeof(PaddedSevHashTable)) {
+ error_setg(errp, "SEV: guest firmware hashes table area is invalid "
+ "(base=0x%x size=0x%x)", area->base, area->size);
+ return false;
+ }
+
+ return klass->build_kernel_loader_hashes(sev_common, area, ctx, errp);
+}
+
static char *
sev_common_get_sev_device(Object *obj, Error **errp)
{
@@ -1998,6 +2051,7 @@ sev_guest_class_init(ObjectClass *oc, void *data)
SevCommonStateClass *klass = SEV_COMMON_CLASS(oc);
X86ConfidentialGuestClass *x86_klass = X86_CONFIDENTIAL_GUEST_CLASS(oc);
+ klass->build_kernel_loader_hashes = sev_build_kernel_loader_hashes;
klass->launch_start = sev_launch_start;
klass->launch_finish = sev_launch_finish;
klass->launch_update_data = sev_launch_update_data;
@@ -2242,6 +2296,7 @@ sev_snp_guest_class_init(ObjectClass *oc, void *data)
SevCommonStateClass *klass = SEV_COMMON_CLASS(oc);
X86ConfidentialGuestClass *x86_klass = X86_CONFIDENTIAL_GUEST_CLASS(oc);
+ klass->build_kernel_loader_hashes = sev_snp_build_kernel_loader_hashes;
klass->launch_start = sev_snp_launch_start;
klass->launch_finish = sev_snp_launch_finish;
klass->launch_update_data = sev_snp_launch_update_data;