Files
qemu/backends/igvm.c
Luigi Leonardi 1c4bd8f13c igvm: add device tree parameter support
Coconut SVSM, with the upcoming device tree support [1], will use
the IGVM device tree parameter to discover virtio-mmio and ISA serial
devices instead of relying on the fw_cfg interface, which is
QEMU-specific.

The device tree is packed before copying into the IGVM parameter area
to reduce its size, since IGVM files can define tighter memory
constraints for parameter areas. Packing is done in the generic IGVM
backend rather than in per-architecture device tree setup code, so
that each architecture does not need to handle it individually.

[1] https://github.com/coconut-svsm/svsm/pull/1006

Signed-off-by: Luigi Leonardi <leonardi@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-ID: <20260626-microvm_device_tree-v6-3-9cd13cf057e2@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2026-07-02 11:14:19 +02:00

1099 lines
38 KiB
C

/*
* QEMU IGVM configuration backend for guests
*
* Copyright (C) 2023-2024 SUSE
*
* Authors:
* Roy Hopkins <roy.hopkins@randomman.co.uk>
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "qemu/target-info-qapi.h"
#include "system/igvm.h"
#include "system/igvm-cfg.h"
#include "system/igvm-internal.h"
#include "system/memory.h"
#include "system/address-spaces.h"
#include "hw/core/cpu.h"
#include "trace.h"
#include <igvm/igvm.h>
#include <igvm/igvm_defs.h>
#ifdef CONFIG_FDT
#include <libfdt.h>
#endif
#ifndef IGVM_VHT_OPTIONAL_BIT
#define IGVM_VHT_OPTIONAL_BIT (1U << 31)
#endif
/*
* Bit 31 of the variable header type indicates that the header is
* optional and can be safely ignored by a loader that does not
* support it. If the bit is clear, the file cannot be loaded.
* https://docs.rs/igvm_defs/0.4.0/igvm_defs/struct.IgvmVariableHeaderType.html
*/
static IgvmVariableHeaderType igvm_vht_type(IgvmVariableHeaderType type)
{
return type & ~IGVM_VHT_OPTIONAL_BIT;
}
static bool igvm_vht_optional(IgvmVariableHeaderType type)
{
return !!(type & IGVM_VHT_OPTIONAL_BIT);
}
/*
* Some directives are specific to particular confidential computing platforms.
* Define required types for each of those platforms here.
*/
/* SEV/SEV-ES/SEV-SNP */
/*
* These structures are defined in "SEV Secure Nested Paging Firmware ABI
* Specification" Rev 1.58, section 8.18.
*/
struct QEMU_PACKED sev_id_block {
uint8_t ld[48];
uint8_t family_id[16];
uint8_t image_id[16];
uint32_t version;
uint32_t guest_svn;
uint64_t policy;
};
struct QEMU_PACKED sev_id_authentication {
uint32_t id_key_alg;
uint32_t auth_key_algo;
uint8_t reserved[56];
uint8_t id_block_sig[512];
uint8_t id_key[1028];
uint8_t reserved2[60];
uint8_t id_key_sig[512];
uint8_t author_key[1028];
uint8_t reserved3[892];
};
#define IGVM_SEV_ID_BLOCK_VERSION 1
QIgvmParameterData*
qigvm_find_param_entry(QIgvm *igvm, uint32_t parameter_area_index,
Error **errp)
{
QIgvmParameterData *param_entry;
QTAILQ_FOREACH(param_entry, &igvm->parameter_data, next)
{
if (param_entry->index == parameter_area_index) {
return param_entry;
}
}
error_setg(errp, "IGVM: parameter area index %u not found",
parameter_area_index);
return NULL;
}
static int qigvm_directive_page_data(QIgvm *ctx, const uint8_t *header_data,
Error **errp);
static int qigvm_directive_vp_context(QIgvm *ctx, const uint8_t *header_data,
Error **errp);
static int qigvm_directive_parameter_area(QIgvm *ctx,
const uint8_t *header_data,
Error **errp);
static int qigvm_directive_parameter_insert(QIgvm *ctx,
const uint8_t *header_data,
Error **errp);
static int qigvm_directive_memory_map(QIgvm *ctx, const uint8_t *header_data,
Error **errp);
static int qigvm_directive_vp_count(QIgvm *ctx, const uint8_t *header_data,
Error **errp);
static int qigvm_directive_environment_info(QIgvm *ctx,
const uint8_t *header_data,
Error **errp);
static int qigvm_directive_required_memory(QIgvm *ctx,
const uint8_t *header_data,
Error **errp);
static int qigvm_directive_snp_id_block(QIgvm *ctx, const uint8_t *header_data,
Error **errp);
static int qigvm_initialization_guest_policy(QIgvm *ctx,
const uint8_t *header_data,
Error **errp);
#ifdef CONFIG_FDT
static int qigvm_directive_device_tree(QIgvm *ctx, const uint8_t *header_data,
Error **errp);
#endif
struct QIGVMHandler {
IgvmVariableHeaderType type;
IgvmHeaderSection section;
int (*handler)(QIgvm *ctx, const uint8_t *header_data, Error **errp);
};
static struct QIGVMHandler handlers[] = {
{ IGVM_VHT_PAGE_DATA, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_page_data },
{ IGVM_VHT_VP_CONTEXT, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_vp_context },
{ IGVM_VHT_PARAMETER_AREA, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_parameter_area },
{ IGVM_VHT_PARAMETER_INSERT, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_parameter_insert },
{ IGVM_VHT_MEMORY_MAP, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_memory_map },
{ IGVM_VHT_VP_COUNT_PARAMETER, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_vp_count },
{ IGVM_VHT_ENVIRONMENT_INFO_PARAMETER, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_environment_info },
{ IGVM_VHT_REQUIRED_MEMORY, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_required_memory },
{ IGVM_VHT_SNP_ID_BLOCK, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_snp_id_block },
{ IGVM_VHT_GUEST_POLICY, IGVM_HEADER_SECTION_INITIALIZATION,
qigvm_initialization_guest_policy },
{ IGVM_VHT_MADT, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_madt },
#ifdef CONFIG_FDT
{ IGVM_VHT_DEVICE_TREE, IGVM_HEADER_SECTION_DIRECTIVE,
qigvm_directive_device_tree },
#endif
};
static int qigvm_handler(QIgvm *ctx, IgvmVariableHeaderType raw_type,
Error **errp)
{
size_t handler;
IgvmHandle header_handle;
const uint8_t *header_data;
int result;
IgvmVariableHeaderType type = igvm_vht_type(raw_type);
for (handler = 0; handler < G_N_ELEMENTS(handlers); handler++) {
if (handlers[handler].type != type) {
continue;
}
header_handle = igvm_get_header(ctx->file, handlers[handler].section,
ctx->current_header_index);
if (header_handle < 0) {
error_setg(
errp,
"IGVM file is invalid: Failed to read directive header (code: %d)",
(int)header_handle);
return -1;
}
header_data = igvm_get_buffer(ctx->file, header_handle);
if (header_data != NULL) {
header_data += sizeof(IGVM_VHS_VARIABLE_HEADER);
result = handlers[handler].handler(ctx, header_data, errp);
} else {
error_setg(errp,
"IGVM: No buffer for handle %d: "
"(type 0x%X)",
header_handle, type);
result = -1;
}
igvm_free_buffer(ctx->file, header_handle);
return result;
}
if (igvm_vht_optional(raw_type)) {
warn_report("IGVM: Skipping unsupported optional header type 0x%"
PRIX32, type);
return 0;
}
error_setg(errp,
"IGVM: Unknown header type encountered when processing file: "
"(type 0x%X)",
type);
return -1;
}
static void *qigvm_prepare_memory(QIgvm *ctx, uint64_t addr, uint64_t size,
int region_identifier, Error **errp)
{
ERRP_GUARD();
MemoryRegion *igvm_pages = NULL;
Int128 gpa_region_size;
MemoryRegionSection mrs =
memory_region_find(get_system_memory(), addr, size);
if (mrs.mr) {
if (!memory_region_is_ram(mrs.mr)) {
memory_region_unref(mrs.mr);
error_setg(
errp,
"Processing of IGVM file failed: Could not prepare memory "
"at address 0x%" PRIx64 " due to existing non-RAM region",
addr);
return NULL;
}
gpa_region_size = int128_make64(size);
if (int128_lt(mrs.size, gpa_region_size)) {
memory_region_unref(mrs.mr);
error_setg(
errp,
"Processing of IGVM file failed: Could not prepare memory "
"at address 0x%" PRIx64 ": region size 0x%" PRIx64 " exceeded",
addr, size);
return NULL;
}
return qemu_map_ram_ptr(mrs.mr->ram_block, mrs.offset_within_region);
} else {
/*
* The region_identifier is the is the index of the IGVM directive that
* contains the page with the lowest GPA in the region. This will
* generate a unique region name.
*/
g_autofree char *region_name =
g_strdup_printf("igvm.%X", region_identifier);
igvm_pages = g_new0(MemoryRegion, 1);
if (ctx->machine_state->cgs &&
ctx->machine_state->cgs->require_guest_memfd) {
if (!memory_region_init_ram_guest_memfd(igvm_pages, NULL,
region_name, size, errp)) {
g_free(igvm_pages);
return NULL;
}
} else {
if (!memory_region_init_ram(igvm_pages, NULL, region_name, size,
errp)) {
g_free(igvm_pages);
return NULL;
}
}
memory_region_add_subregion(get_system_memory(), addr, igvm_pages);
return memory_region_get_ram_ptr(igvm_pages);
}
}
static int qigvm_type_to_cgs_type(IgvmPageDataType memory_type, bool unmeasured,
bool zero)
{
switch (memory_type) {
case IGVM_PAGE_DATA_TYPE_NORMAL: {
if (unmeasured) {
return CGS_PAGE_TYPE_UNMEASURED;
} else {
return zero ? CGS_PAGE_TYPE_ZERO : CGS_PAGE_TYPE_NORMAL;
}
}
case IGVM_PAGE_DATA_TYPE_SECRETS:
return CGS_PAGE_TYPE_SECRETS;
case IGVM_PAGE_DATA_TYPE_CPUID_DATA:
return CGS_PAGE_TYPE_CPUID;
case IGVM_PAGE_DATA_TYPE_CPUID_XF:
return CGS_PAGE_TYPE_CPUID;
default:
return -1;
}
}
static bool qigvm_page_attrs_equal(IgvmHandle igvm, unsigned header_index,
const IGVM_VHS_PAGE_DATA *page_1,
const IGVM_VHS_PAGE_DATA *page_2)
{
IgvmHandle data_handle1, data_handle2;
/*
* If one page has data and the other doesn't then this results in different
* page types: NORMAL vs ZERO.
*/
data_handle1 = igvm_get_header_data(igvm, IGVM_HEADER_SECTION_DIRECTIVE,
header_index - 1);
data_handle2 =
igvm_get_header_data(igvm, IGVM_HEADER_SECTION_DIRECTIVE, header_index);
if ((data_handle1 == IGVMAPI_NO_DATA ||
data_handle2 == IGVMAPI_NO_DATA) &&
data_handle1 != data_handle2) {
return false;
}
return ((*(const uint32_t *)&page_1->flags ==
*(const uint32_t *)&page_2->flags) &&
(page_1->data_type == page_2->data_type) &&
(page_1->compatibility_mask == page_2->compatibility_mask));
}
static int qigvm_process_mem_region(QIgvm *ctx, unsigned start_index,
uint64_t gpa_start, unsigned page_count,
const IgvmPageDataFlags *flags,
const IgvmPageDataType page_type,
Error **errp)
{
uint8_t *region;
IgvmHandle data_handle;
const void *data;
uint32_t data_size;
unsigned page_index;
bool zero = true;
const uint64_t page_size = flags->is_2mb_page ? 0x200000 : 0x1000;
int result;
int cgs_page_type;
region = qigvm_prepare_memory(ctx, gpa_start, page_count * page_size,
start_index, errp);
if (!region) {
return -1;
}
for (page_index = 0; page_index < page_count; page_index++) {
data_handle = igvm_get_header_data(
ctx->file, IGVM_HEADER_SECTION_DIRECTIVE, page_index + start_index);
if (data_handle == IGVMAPI_NO_DATA) {
/* No data indicates a zero page */
memset(&region[page_index * page_size], 0, page_size);
} else if (data_handle < 0) {
error_setg(
errp,
"IGVM file contains invalid page data for directive with "
"index %d",
page_index + start_index);
return -1;
} else {
zero = false;
data_size = igvm_get_buffer_size(ctx->file, data_handle);
if (data_size < page_size) {
memset(&region[page_index * page_size], 0, page_size);
} else if (data_size > page_size) {
error_setg(errp,
"IGVM file contains page data with invalid size for "
"directive with index %d",
page_index + start_index);
return -1;
}
data = igvm_get_buffer(ctx->file, data_handle);
if (data == NULL) {
error_setg(errp, "IGVM: No buffer for handle %d", data_handle);
igvm_free_buffer(ctx->file, data_handle);
return -1;
}
memcpy(&region[page_index * page_size], data, data_size);
igvm_free_buffer(ctx->file, data_handle);
}
}
/*
* If a confidential guest support object is provided then use it to set the
* guest state.
*/
if (ctx->machine_state->cgs) {
cgs_page_type =
qigvm_type_to_cgs_type(page_type, flags->unmeasured, zero);
if (cgs_page_type < 0) {
error_setg(errp,
"Invalid page type in IGVM file. Directives: %d to %d, "
"page type: %d",
start_index, start_index + page_count, page_type);
return -1;
}
result = ctx->cgsc->set_guest_state(
gpa_start, region, page_size * page_count, cgs_page_type, 0, errp);
if (result < 0) {
return result;
}
}
return 0;
}
static int qigvm_process_mem_page(QIgvm *ctx,
const IGVM_VHS_PAGE_DATA *page_data,
Error **errp)
{
if (page_data) {
if (ctx->region_page_count == 0) {
ctx->region_start = page_data->gpa;
ctx->region_start_index = ctx->current_header_index;
} else {
if (!qigvm_page_attrs_equal(ctx->file, ctx->current_header_index,
page_data,
&ctx->region_prev_page_data) ||
((ctx->region_prev_page_data.gpa +
(ctx->region_prev_page_data.flags.is_2mb_page ? 0x200000 :
0x1000)) !=
page_data->gpa) ||
(ctx->region_last_index != (ctx->current_header_index - 1))) {
/* End of current region */
if (qigvm_process_mem_region(
ctx, ctx->region_start_index, ctx->region_start,
ctx->region_page_count,
&ctx->region_prev_page_data.flags,
ctx->region_prev_page_data.data_type, errp) < 0) {
return -1;
}
ctx->region_page_count = 0;
ctx->region_start = page_data->gpa;
ctx->region_start_index = ctx->current_header_index;
}
}
memcpy(&ctx->region_prev_page_data, page_data,
sizeof(ctx->region_prev_page_data));
ctx->region_last_index = ctx->current_header_index;
ctx->region_page_count++;
} else {
if (ctx->region_page_count > 0) {
if (qigvm_process_mem_region(
ctx, ctx->region_start_index, ctx->region_start,
ctx->region_page_count, &ctx->region_prev_page_data.flags,
ctx->region_prev_page_data.data_type, errp) < 0) {
return -1;
}
ctx->region_page_count = 0;
}
}
return 0;
}
static int qigvm_directive_page_data(QIgvm *ctx, const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_PAGE_DATA *page_data =
(const IGVM_VHS_PAGE_DATA *)header_data;
if (page_data->compatibility_mask & ctx->compatibility_mask) {
return qigvm_process_mem_page(ctx, page_data, errp);
}
return 0;
}
static int qigvm_directive_vp_context(QIgvm *ctx, const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_VP_CONTEXT *vp_context =
(const IGVM_VHS_VP_CONTEXT *)header_data;
IgvmHandle data_handle;
uint8_t *data;
int result;
if (!(vp_context->compatibility_mask & ctx->compatibility_mask)) {
return 0;
}
data_handle = igvm_get_header_data(ctx->file, IGVM_HEADER_SECTION_DIRECTIVE,
ctx->current_header_index);
if (data_handle < 0) {
error_setg(errp, "Invalid VP context in IGVM file. Error code: %X",
data_handle);
return -1;
}
data = (uint8_t *)igvm_get_buffer(ctx->file, data_handle);
if (data == NULL) {
error_setg(errp, "IGVM: No buffer for handle %d", data_handle);
result = -1;
goto exit;
}
if (ctx->machine_state->cgs) {
result = ctx->cgsc->set_guest_state(
vp_context->gpa, data, igvm_get_buffer_size(ctx->file, data_handle),
CGS_PAGE_TYPE_VMSA, vp_context->vp_index, errp);
} else if (target_arch() == SYS_EMU_TARGET_X86_64) {
result = qigvm_x86_set_vp_context(data, vp_context->vp_index, errp);
} else {
error_setg(
errp,
"A VP context is present in the IGVM file but is not supported "
"by the current system.");
result = -1;
}
exit:
igvm_free_buffer(ctx->file, data_handle);
if (result < 0) {
return result;
}
return 0;
}
static int qigvm_directive_parameter_area(QIgvm *ctx,
const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_PARAMETER_AREA *param_area =
(const IGVM_VHS_PARAMETER_AREA *)header_data;
QIgvmParameterData *param_entry;
param_entry = g_new0(QIgvmParameterData, 1);
param_entry->size = param_area->number_of_bytes;
param_entry->index = param_area->parameter_area_index;
param_entry->data = g_malloc0(param_entry->size);
QTAILQ_INSERT_TAIL(&ctx->parameter_data, param_entry, next);
return 0;
}
static int qigvm_directive_parameter_insert(QIgvm *ctx,
const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_PARAMETER_INSERT *param =
(const IGVM_VHS_PARAMETER_INSERT *)header_data;
QIgvmParameterData *param_entry;
int result;
void *region;
if (!(param->compatibility_mask & ctx->compatibility_mask)) {
return 0;
}
param_entry = qigvm_find_param_entry(ctx,
param->parameter_area_index, errp);
if (param_entry == NULL) {
return -1;
}
region = qigvm_prepare_memory(ctx, param->gpa, param_entry->size,
ctx->current_header_index, errp);
if (!region) {
return -1;
}
memcpy(region, param_entry->data, param_entry->size);
g_free(param_entry->data);
param_entry->data = NULL;
/*
* If a confidential guest support object is provided then use it to
* set the guest state.
*/
if (ctx->machine_state->cgs) {
result = ctx->cgsc->set_guest_state(param->gpa, region,
param_entry->size,
CGS_PAGE_TYPE_UNMEASURED, 0,
errp);
if (result < 0) {
return -1;
}
}
return 0;
}
static int qigvm_cmp_mm_entry(const void *a, const void *b)
{
const IGVM_VHS_MEMORY_MAP_ENTRY *entry_a =
(const IGVM_VHS_MEMORY_MAP_ENTRY *)a;
const IGVM_VHS_MEMORY_MAP_ENTRY *entry_b =
(const IGVM_VHS_MEMORY_MAP_ENTRY *)b;
if (entry_a->starting_gpa_page_number < entry_b->starting_gpa_page_number) {
return -1;
} else if (entry_a->starting_gpa_page_number >
entry_b->starting_gpa_page_number) {
return 1;
} else {
return 0;
}
}
static int qigvm_directive_memory_map(QIgvm *ctx, const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_PARAMETER *param = (const IGVM_VHS_PARAMETER *)header_data;
int (*get_mem_map_entry)(int index, ConfidentialGuestMemoryMapEntry *entry,
Error **errp) = NULL;
QIgvmParameterData *param_entry;
int max_entry_count;
int entry = 0;
IGVM_VHS_MEMORY_MAP_ENTRY *mm_entry;
ConfidentialGuestMemoryMapEntry cgmm_entry;
int retval = 0;
if (ctx->machine_state->cgs && ctx->cgsc->get_mem_map_entry) {
get_mem_map_entry = ctx->cgsc->get_mem_map_entry;
} else if (target_arch() == SYS_EMU_TARGET_X86_64) {
get_mem_map_entry = qigvm_x86_get_mem_map_entry;
} else {
error_setg(errp,
"IGVM file contains a memory map but this is not supported "
"by the current system.");
return -1;
}
/* Find the parameter area that should hold the memory map */
param_entry = qigvm_find_param_entry(ctx,
param->parameter_area_index, errp);
if (param_entry == NULL) {
return -1;
}
max_entry_count = param_entry->size / sizeof(IGVM_VHS_MEMORY_MAP_ENTRY);
mm_entry = (IGVM_VHS_MEMORY_MAP_ENTRY *)param_entry->data;
retval = get_mem_map_entry(entry, &cgmm_entry, errp);
while (retval == 0) {
if (entry >= max_entry_count) {
error_setg(
errp,
"IGVM: guest memory map size exceeds parameter area defined "
"in IGVM file");
return -1;
}
mm_entry[entry].starting_gpa_page_number = cgmm_entry.gpa >> 12;
mm_entry[entry].number_of_pages = cgmm_entry.size >> 12;
switch (cgmm_entry.type) {
case CGS_MEM_RAM:
mm_entry[entry].entry_type = IGVM_MEMORY_MAP_ENTRY_TYPE_MEMORY;
break;
case CGS_MEM_RESERVED:
mm_entry[entry].entry_type =
IGVM_MEMORY_MAP_ENTRY_TYPE_PLATFORM_RESERVED;
break;
case CGS_MEM_ACPI:
mm_entry[entry].entry_type =
IGVM_MEMORY_MAP_ENTRY_TYPE_PLATFORM_RESERVED;
break;
case CGS_MEM_NVS:
mm_entry[entry].entry_type = IGVM_MEMORY_MAP_ENTRY_TYPE_PERSISTENT;
break;
case CGS_MEM_UNUSABLE:
mm_entry[entry].entry_type =
IGVM_MEMORY_MAP_ENTRY_TYPE_PLATFORM_RESERVED;
break;
}
retval = get_mem_map_entry(++entry, &cgmm_entry, errp);
}
if (retval < 0) {
return retval;
}
/* The entries need to be sorted */
qsort(mm_entry, entry, sizeof(IGVM_VHS_MEMORY_MAP_ENTRY),
qigvm_cmp_mm_entry);
return 0;
}
static int qigvm_directive_vp_count(QIgvm *ctx, const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_PARAMETER *param = (const IGVM_VHS_PARAMETER *)header_data;
QIgvmParameterData *param_entry;
uint32_t *vp_count;
CPUState *cpu;
param_entry = qigvm_find_param_entry(ctx,
param->parameter_area_index, errp);
if (param_entry == NULL) {
return -1;
}
vp_count = (uint32_t *)(param_entry->data + param->byte_offset);
*vp_count = 0;
CPU_FOREACH(cpu)
{
(*vp_count)++;
}
return 0;
}
static int qigvm_directive_environment_info(QIgvm *ctx,
const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_PARAMETER *param = (const IGVM_VHS_PARAMETER *)header_data;
QIgvmParameterData *param_entry;
IgvmEnvironmentInfo *environmental_state;
param_entry = qigvm_find_param_entry(ctx,
param->parameter_area_index, errp);
if (param_entry == NULL) {
return -1;
}
environmental_state =
(IgvmEnvironmentInfo *)(param_entry->data + param->byte_offset);
environmental_state->memory_is_shared = 1;
return 0;
}
static int qigvm_directive_required_memory(QIgvm *ctx,
const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_REQUIRED_MEMORY *mem =
(const IGVM_VHS_REQUIRED_MEMORY *)header_data;
uint8_t *region;
int result;
if (!(mem->compatibility_mask & ctx->compatibility_mask)) {
return 0;
}
region = qigvm_prepare_memory(ctx, mem->gpa, mem->number_of_bytes,
ctx->current_header_index, errp);
if (!region) {
return -1;
}
if (ctx->machine_state->cgs) {
result =
ctx->cgsc->set_guest_state(mem->gpa, region, mem->number_of_bytes,
CGS_PAGE_TYPE_REQUIRED_MEMORY, 0, errp);
if (result < 0) {
return result;
}
}
return 0;
}
static int qigvm_directive_snp_id_block(QIgvm *ctx, const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_SNP_ID_BLOCK *igvm_id =
(const IGVM_VHS_SNP_ID_BLOCK *)header_data;
if (!(igvm_id->compatibility_mask & ctx->compatibility_mask)) {
return 0;
}
if (ctx->id_block) {
error_setg(errp, "IGVM: Multiple ID blocks encountered "
"in IGVM file.");
return -1;
}
ctx->id_block = g_new0(struct sev_id_block, 1);
ctx->id_auth = g_new0(struct sev_id_authentication, 1);
memcpy(ctx->id_block->family_id, igvm_id->family_id,
sizeof(ctx->id_block->family_id));
memcpy(ctx->id_block->image_id, igvm_id->image_id,
sizeof(ctx->id_block->image_id));
ctx->id_block->guest_svn = igvm_id->guest_svn;
ctx->id_block->version = IGVM_SEV_ID_BLOCK_VERSION;
memcpy(ctx->id_block->ld, igvm_id->ld, sizeof(ctx->id_block->ld));
ctx->id_auth->id_key_alg = igvm_id->id_key_algorithm;
assert(sizeof(igvm_id->id_key_signature) <=
sizeof(ctx->id_auth->id_block_sig));
memcpy(ctx->id_auth->id_block_sig, &igvm_id->id_key_signature,
sizeof(igvm_id->id_key_signature));
ctx->id_auth->auth_key_algo = igvm_id->author_key_algorithm;
assert(sizeof(igvm_id->author_key_signature) <=
sizeof(ctx->id_auth->id_key_sig));
memcpy(ctx->id_auth->id_key_sig, &igvm_id->author_key_signature,
sizeof(igvm_id->author_key_signature));
/*
* SEV and IGVM public key structure population are slightly different.
* See SEV Secure Nested Paging Firmware ABI Specification, Chapter 10.
*/
*((uint32_t *)ctx->id_auth->id_key) = igvm_id->id_public_key.curve;
memcpy(&ctx->id_auth->id_key[4], &igvm_id->id_public_key.qx, 72);
memcpy(&ctx->id_auth->id_key[76], &igvm_id->id_public_key.qy, 72);
*((uint32_t *)ctx->id_auth->author_key) =
igvm_id->author_public_key.curve;
memcpy(&ctx->id_auth->author_key[4], &igvm_id->author_public_key.qx,
72);
memcpy(&ctx->id_auth->author_key[76], &igvm_id->author_public_key.qy,
72);
return 0;
}
#ifdef CONFIG_FDT
static int qigvm_directive_device_tree(QIgvm *ctx, const uint8_t *header_data,
Error **errp)
{
const IGVM_VHS_PARAMETER *param = (const IGVM_VHS_PARAMETER *)header_data;
g_autofree void *fdt_packed = NULL;
QIgvmParameterData *param_entry;
uint32_t fdt_size;
param_entry = qigvm_find_param_entry(ctx,
param->parameter_area_index, errp);
if (param_entry == NULL) {
return -1;
}
if (ctx->machine_state->fdt == NULL) {
error_setg(errp, "IGVM: device tree not available");
return -1;
}
fdt_size = fdt_totalsize(ctx->machine_state->fdt);
fdt_packed = g_memdup2(ctx->machine_state->fdt, fdt_size);
if (fdt_pack(fdt_packed)) {
error_setg(errp, "IGVM: failed to pack device tree");
return -1;
}
fdt_size = fdt_totalsize(fdt_packed);
if (fdt_size > param_entry->size) {
error_setg(errp,
"IGVM: device tree size exceeds parameter area"
" defined in IGVM file");
return -1;
}
memcpy(param_entry->data, fdt_packed, fdt_size);
return 0;
}
#endif
static int qigvm_initialization_guest_policy(QIgvm *ctx,
const uint8_t *header_data, Error **errp)
{
const IGVM_VHS_GUEST_POLICY *guest =
(const IGVM_VHS_GUEST_POLICY *)header_data;
if (guest->compatibility_mask & ctx->compatibility_mask) {
ctx->sev_policy = guest->policy;
}
return 0;
}
static int qigvm_supported_platform_compat_mask(QIgvm *ctx, Error **errp)
{
int32_t header_count;
unsigned header_index;
IgvmHandle header_handle;
IGVM_VHS_SUPPORTED_PLATFORM *platform;
uint32_t compatibility_mask_sev = 0;
uint32_t compatibility_mask_sev_es = 0;
uint32_t compatibility_mask_sev_snp = 0;
uint32_t compatibility_mask = 0;
header_count = igvm_header_count(ctx->file, IGVM_HEADER_SECTION_PLATFORM);
if (header_count < 0) {
error_setg(errp,
"Invalid platform header count in IGVM file. Error code: %X",
header_count);
return -1;
}
for (header_index = 0; header_index < (unsigned)header_count;
header_index++) {
IgvmVariableHeaderType typ = igvm_get_header_type(
ctx->file, IGVM_HEADER_SECTION_PLATFORM, header_index);
typ = igvm_vht_type(typ);
if (typ == IGVM_VHT_SUPPORTED_PLATFORM) {
header_handle = igvm_get_header(
ctx->file, IGVM_HEADER_SECTION_PLATFORM, header_index);
if (header_handle < 0) {
error_setg(errp,
"Invalid platform header in IGVM file. "
"Index: %d, Error code: %X",
header_index, header_handle);
return -1;
}
platform =
(IGVM_VHS_SUPPORTED_PLATFORM *)(igvm_get_buffer(ctx->file,
header_handle));
if (platform == NULL) {
error_setg(errp, "IGVM: No buffer for handle %d", header_handle);
igvm_free_buffer(ctx->file, header_handle);
return -1;
}
platform = (IGVM_VHS_SUPPORTED_PLATFORM *)((void *)platform
+ sizeof(IGVM_VHS_VARIABLE_HEADER));
if ((platform->platform_type == IGVM_PLATFORM_TYPE_SEV_ES) &&
ctx->machine_state->cgs) {
if (ctx->cgsc->check_support(
CGS_PLATFORM_SEV_ES, platform->platform_version,
platform->highest_vtl, platform->shared_gpa_boundary)) {
compatibility_mask_sev_es = platform->compatibility_mask;
}
} else if ((platform->platform_type == IGVM_PLATFORM_TYPE_SEV) &&
ctx->machine_state->cgs) {
if (ctx->cgsc->check_support(
CGS_PLATFORM_SEV, platform->platform_version,
platform->highest_vtl, platform->shared_gpa_boundary)) {
compatibility_mask_sev = platform->compatibility_mask;
}
} else if ((platform->platform_type ==
IGVM_PLATFORM_TYPE_SEV_SNP) &&
ctx->machine_state->cgs) {
if (ctx->cgsc->check_support(
CGS_PLATFORM_SEV_SNP, platform->platform_version,
platform->highest_vtl, platform->shared_gpa_boundary)) {
compatibility_mask_sev_snp = platform->compatibility_mask;
}
} else if (platform->platform_type == IGVM_PLATFORM_TYPE_NATIVE) {
compatibility_mask = platform->compatibility_mask;
}
igvm_free_buffer(ctx->file, header_handle);
}
}
/* Choose the strongest supported isolation technology */
if (compatibility_mask_sev_snp != 0) {
ctx->compatibility_mask = compatibility_mask_sev_snp;
ctx->platform_type = IGVM_PLATFORM_TYPE_SEV_SNP;
} else if (compatibility_mask_sev_es != 0) {
ctx->compatibility_mask = compatibility_mask_sev_es;
ctx->platform_type = IGVM_PLATFORM_TYPE_SEV_ES;
} else if (compatibility_mask_sev != 0) {
ctx->compatibility_mask = compatibility_mask_sev;
ctx->platform_type = IGVM_PLATFORM_TYPE_SEV;
} else if (compatibility_mask != 0) {
ctx->compatibility_mask = compatibility_mask;
ctx->platform_type = IGVM_PLATFORM_TYPE_NATIVE;
} else {
error_setg(
errp,
"IGVM file does not describe a compatible supported platform");
return -1;
}
return 0;
}
static int qigvm_handle_policy(QIgvm *ctx, Error **errp)
{
if (ctx->platform_type == IGVM_PLATFORM_TYPE_SEV_SNP) {
int id_block_len = 0;
int id_auth_len = 0;
if (ctx->id_block) {
ctx->id_block->policy = ctx->sev_policy;
id_block_len = sizeof(struct sev_id_block);
id_auth_len = sizeof(struct sev_id_authentication);
}
return ctx->cgsc->set_guest_policy(GUEST_POLICY_SEV, ctx->sev_policy,
ctx->id_block, id_block_len,
ctx->id_auth, id_auth_len, errp);
}
return 0;
}
IgvmHandle qigvm_file_init(char *filename, Error **errp)
{
IgvmHandle igvm;
g_autofree uint8_t *buf = NULL;
unsigned long len;
g_autoptr(GError) gerr = NULL;
if (!g_file_get_contents(filename, (gchar **)&buf, &len, &gerr)) {
error_setg(errp, "Unable to load %s: %s", filename, gerr->message);
return -1;
}
igvm = igvm_new_from_binary(buf, len);
if (igvm < 0) {
error_setg(errp, "Unable to parse IGVM file %s: %d", filename, igvm);
return -1;
}
trace_igvm_file_loaded(filename, igvm);
return igvm;
}
int qigvm_process_file(IgvmCfg *cfg, MachineState *machine_state,
bool onlyVpContext, Error **errp)
{
int32_t header_count;
QIgvmParameterData *parameter;
int retval = -1;
QIgvm ctx;
memset(&ctx, 0, sizeof(ctx));
if (cfg->file < 0) {
error_setg(errp, "No IGVM file loaded.");
return -1;
}
ctx.file = cfg->file;
trace_igvm_process_file(cfg->file, onlyVpContext);
ctx.machine_state = machine_state;
/*
* The ConfidentialGuestSupport object is optional and allows a confidential
* guest platform to perform extra processing, such as page measurement, on
* IGVM directives.
*/
ctx.cgsc = machine_state->cgs ?
CONFIDENTIAL_GUEST_SUPPORT_GET_CLASS(machine_state->cgs) :
NULL;
/*
* Check that the IGVM file provides configuration for the current
* platform
*/
if (qigvm_supported_platform_compat_mask(&ctx, errp) < 0) {
goto cleanup;
}
header_count = igvm_header_count(ctx.file, IGVM_HEADER_SECTION_DIRECTIVE);
if (header_count <= 0) {
error_setg(
errp, "Invalid directive header count in IGVM file. Error code: %X",
header_count);
goto cleanup;
}
QTAILQ_INIT(&ctx.parameter_data);
for (ctx.current_header_index = 0;
ctx.current_header_index < (unsigned)header_count;
ctx.current_header_index++) {
IgvmVariableHeaderType raw_type = igvm_get_header_type(
ctx.file, IGVM_HEADER_SECTION_DIRECTIVE, ctx.current_header_index);
if (!onlyVpContext || igvm_vht_type(raw_type) == IGVM_VHT_VP_CONTEXT) {
if (qigvm_handler(&ctx, raw_type, errp) < 0) {
goto cleanup_parameters;
}
}
}
/*
* If only processing the VP context then we don't need to process
* any more of the file.
*/
if (onlyVpContext) {
retval = 0;
goto cleanup_parameters;
}
header_count =
igvm_header_count(ctx.file, IGVM_HEADER_SECTION_INITIALIZATION);
if (header_count < 0) {
error_setg(
errp,
"Invalid initialization header count in IGVM file. Error code: %X",
header_count);
goto cleanup_parameters;
}
for (ctx.current_header_index = 0;
ctx.current_header_index < (unsigned)header_count;
ctx.current_header_index++) {
IgvmVariableHeaderType type =
igvm_get_header_type(ctx.file, IGVM_HEADER_SECTION_INITIALIZATION,
ctx.current_header_index);
if (qigvm_handler(&ctx, type, errp) < 0) {
goto cleanup_parameters;
}
}
/*
* Contiguous pages of data with compatible flags are grouped together in
* order to reduce the number of memory regions we create. Make sure the
* last group is processed with this call.
*/
retval = qigvm_process_mem_page(&ctx, NULL, errp);
if (retval == 0) {
retval = qigvm_handle_policy(&ctx, errp);
}
cleanup_parameters:
QTAILQ_FOREACH(parameter, &ctx.parameter_data, next)
{
g_free(parameter->data);
parameter->data = NULL;
}
g_free(ctx.id_block);
g_free(ctx.id_auth);
cleanup:
return retval;
}