diff options
Diffstat (limited to 'backends/igvm.c')
| -rw-r--r-- | backends/igvm.c | 988 |
1 files changed, 988 insertions, 0 deletions
diff --git a/backends/igvm.c b/backends/igvm.c new file mode 100644 index 0000000..9ad4158 --- /dev/null +++ b/backends/igvm.c @@ -0,0 +1,988 @@ +/* + * 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 "igvm.h" +#include "qapi/error.h" +#include "system/memory.h" +#include "system/address-spaces.h" +#include "hw/core/cpu.h" + +#include <igvm/igvm.h> +#include <igvm/igvm_defs.h> + +typedef struct QIgvmParameterData { + QTAILQ_ENTRY(QIgvmParameterData) next; + uint8_t *data; + uint32_t size; + uint32_t index; +} QIgvmParameterData; + +/* + * 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 + +/* + * QIgvm contains the information required during processing + * of a single IGVM file. + */ +typedef struct QIgvm { + IgvmHandle file; + ConfidentialGuestSupport *cgs; + ConfidentialGuestSupportClass *cgsc; + uint32_t compatibility_mask; + unsigned current_header_index; + QTAILQ_HEAD(, QIgvmParameterData) parameter_data; + IgvmPlatformType platform_type; + + /* + * SEV-SNP platforms can contain an ID block and authentication + * that should be verified by the guest. + */ + struct sev_id_block *id_block; + struct sev_id_authentication *id_auth; + + /* Define the guest policy for SEV guests */ + uint64_t sev_policy; + + /* These variables keep track of contiguous page regions */ + IGVM_VHS_PAGE_DATA region_prev_page_data; + uint64_t region_start; + unsigned region_start_index; + unsigned region_last_index; + unsigned region_page_count; +} QIgvm; + +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); + +struct QIGVMHandler { + uint32_t type; + uint32_t 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 }, +}; + +static int qigvm_handler(QIgvm *ctx, uint32_t type, Error **errp) +{ + size_t handler; + IgvmHandle header_handle; + const uint8_t *header_data; + int result; + + 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) + + sizeof(IGVM_VHS_VARIABLE_HEADER); + result = handlers[handler].handler(ctx, header_data, errp); + igvm_free_buffer(ctx->file, header_handle); + return result; + } + 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%lX 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%lX: region size exceeded", + addr); + 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->cgs && ctx->cgs->require_guest_memfd) { + if (!memory_region_init_ram_guest_memfd(igvm_pages, NULL, + region_name, size, errp)) { + return NULL; + } + } else { + if (!memory_region_init_ram(igvm_pages, NULL, region_name, size, + errp)) { + 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(®ion[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(®ion[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); + memcpy(®ion[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->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; + } + + /* + * A confidential guest support object must be provided for setting + * a VP context. + */ + if (!ctx->cgs) { + error_setg( + errp, + "A VP context is present in the IGVM file but is not supported " + "by the current system."); + return -1; + } + + 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); + 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); + 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; + } + + QTAILQ_FOREACH(param_entry, &ctx->parameter_data, next) + { + if (param_entry->index == param->parameter_area_index) { + 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->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; + 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->cgs) { + 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 */ + QTAILQ_FOREACH(param_entry, &ctx->parameter_data, next) + { + if (param_entry->index == param->parameter_area_index) { + max_entry_count = + param_entry->size / sizeof(IGVM_VHS_MEMORY_MAP_ENTRY); + mm_entry = (IGVM_VHS_MEMORY_MAP_ENTRY *)param_entry->data; + + retval = ctx->cgsc->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 = + ctx->cgsc->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); + + break; + } + } + 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; + + QTAILQ_FOREACH(param_entry, &ctx->parameter_data, next) + { + if (param_entry->index == param->parameter_area_index) { + vp_count = (uint32_t *)(param_entry->data + param->byte_offset); + *vp_count = 0; + CPU_FOREACH(cpu) + { + (*vp_count)++; + } + break; + } + } + 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; + + QTAILQ_FOREACH(param_entry, &ctx->parameter_data, next) + { + if (param_entry->index == param->parameter_area_index) { + environmental_state = + (IgvmEnvironmentInfo *)(param_entry->data + param->byte_offset); + environmental_state->memory_is_shared = 1; + break; + } + } + 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->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; +} + +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); + 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) + + sizeof( + IGVM_VHS_VARIABLE_HEADER)); + if ((platform->platform_type == IGVM_PLATFORM_TYPE_SEV_ES) && + ctx->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->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->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; +} + +static 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; + } + return igvm; +} + +int qigvm_process_file(IgvmCfg *cfg, ConfidentialGuestSupport *cgs, + bool onlyVpContext, Error **errp) +{ + int32_t header_count; + QIgvmParameterData *parameter; + int retval = -1; + QIgvm ctx; + + memset(&ctx, 0, sizeof(ctx)); + ctx.file = qigvm_file_init(cfg->filename, errp); + if (ctx.file < 0) { + return -1; + } + + /* + * The ConfidentialGuestSupport object is optional and allows a confidential + * guest platform to perform extra processing, such as page measurement, on + * IGVM directives. + */ + ctx.cgs = cgs; + ctx.cgsc = cgs ? CONFIDENTIAL_GUEST_SUPPORT_GET_CLASS(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 type = igvm_get_header_type( + ctx.file, IGVM_HEADER_SECTION_DIRECTIVE, ctx.current_header_index); + if (!onlyVpContext || (type == IGVM_VHT_VP_CONTEXT)) { + if (qigvm_handler(&ctx, 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: + igvm_free(ctx.file); + + return retval; +} |