/* * QEMU SEV support * * Copyright Advanced Micro Devices 2016-2018 * * Author: * Brijesh Singh * * This work is licensed under the terms of the GNU GPL, version 2 or later. * See the COPYING file in the top-level directory. * */ #include "qemu/osdep.h" #include #include #include #include #include "qapi/error.h" #include "qom/object_interfaces.h" #include "qemu/base64.h" #include "qemu/module.h" #include "qemu/uuid.h" #include "qemu/error-report.h" #include "crypto/hash.h" #include "sysemu/kvm.h" #include "kvm/kvm_i386.h" #include "sev.h" #include "sysemu/sysemu.h" #include "sysemu/runstate.h" #include "trace.h" #include "migration/blocker.h" #include "qom/object.h" #include "monitor/monitor.h" #include "monitor/hmp-target.h" #include "qapi/qapi-commands-misc-target.h" #include "confidential-guest.h" #include "hw/i386/pc.h" #include "exec/address-spaces.h" #include "qemu/queue.h" OBJECT_DECLARE_TYPE(SevCommonState, SevCommonStateClass, SEV_COMMON) OBJECT_DECLARE_TYPE(SevGuestState, SevCommonStateClass, SEV_GUEST) OBJECT_DECLARE_TYPE(SevSnpGuestState, SevCommonStateClass, SEV_SNP_GUEST) /* hard code sha256 digest size */ #define HASH_SIZE 32 typedef struct QEMU_PACKED SevHashTableEntry { QemuUUID guid; uint16_t len; uint8_t hash[HASH_SIZE]; } SevHashTableEntry; typedef struct QEMU_PACKED SevHashTable { QemuUUID guid; uint16_t len; SevHashTableEntry cmdline; SevHashTableEntry initrd; SevHashTableEntry kernel; } SevHashTable; /* * Data encrypted by sev_encrypt_flash() must be padded to a multiple of * 16 bytes. */ typedef struct QEMU_PACKED PaddedSevHashTable { SevHashTable ht; uint8_t padding[ROUND_UP(sizeof(SevHashTable), 16) - sizeof(SevHashTable)]; } PaddedSevHashTable; QEMU_BUILD_BUG_ON(sizeof(PaddedSevHashTable) % 16 != 0); #define SEV_INFO_BLOCK_GUID "00f771de-1a7e-4fcb-890e-68c77e2fb44e" typedef struct __attribute__((__packed__)) SevInfoBlock { /* SEV-ES Reset Vector Address */ uint32_t reset_addr; } SevInfoBlock; #define SEV_HASH_TABLE_RV_GUID "7255371f-3a3b-4b04-927b-1da6efa8d454" typedef struct QEMU_PACKED SevHashTableDescriptor { /* SEV hash table area guest address */ uint32_t base; /* SEV hash table area size (in bytes) */ uint32_t size; } SevHashTableDescriptor; struct SevCommonState { X86ConfidentialGuest parent_obj; int kvm_type; /* configuration parameters */ char *sev_device; uint32_t cbitpos; uint32_t reduced_phys_bits; bool kernel_hashes; /* runtime state */ uint8_t api_major; uint8_t api_minor; uint8_t build_id; int sev_fd; SevState state; uint32_t reset_cs; uint32_t reset_ip; bool reset_data_valid; }; 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); int (*kvm_init)(ConfidentialGuestSupport *cgs, Error **errp); }; /** * SevGuestState: * * The SevGuestState object is used for creating and managing a SEV * guest. * * # $QEMU \ * -object sev-guest,id=sev0 \ * -machine ...,memory-encryption=sev0 */ struct SevGuestState { SevCommonState parent_obj; gchar *measurement; /* configuration parameters */ uint32_t handle; uint32_t policy; char *dh_cert_file; char *session_file; bool legacy_vm_type; }; struct SevSnpGuestState { SevCommonState parent_obj; /* configuration parameters */ char *guest_visible_workarounds; char *id_block; char *id_auth; char *host_data; 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 */ #define DEFAULT_SEV_DEVICE "/dev/sev" #define DEFAULT_SEV_SNP_POLICY 0x30000 typedef struct SevLaunchUpdateData { QTAILQ_ENTRY(SevLaunchUpdateData) next; hwaddr gpa; void *hva; uint64_t len; int type; } SevLaunchUpdateData; static QTAILQ_HEAD(, SevLaunchUpdateData) launch_update; static Error *sev_mig_blocker; static const char *const sev_fw_errlist[] = { [SEV_RET_SUCCESS] = "", [SEV_RET_INVALID_PLATFORM_STATE] = "Platform state is invalid", [SEV_RET_INVALID_GUEST_STATE] = "Guest state is invalid", [SEV_RET_INAVLID_CONFIG] = "Platform configuration is invalid", [SEV_RET_INVALID_LEN] = "Buffer too small", [SEV_RET_ALREADY_OWNED] = "Platform is already owned", [SEV_RET_INVALID_CERTIFICATE] = "Certificate is invalid", [SEV_RET_POLICY_FAILURE] = "Policy is not allowed", [SEV_RET_INACTIVE] = "Guest is not active", [SEV_RET_INVALID_ADDRESS] = "Invalid address", [SEV_RET_BAD_SIGNATURE] = "Bad signature", [SEV_RET_BAD_MEASUREMENT] = "Bad measurement", [SEV_RET_ASID_OWNED] = "ASID is already owned", [SEV_RET_INVALID_ASID] = "Invalid ASID", [SEV_RET_WBINVD_REQUIRED] = "WBINVD is required", [SEV_RET_DFFLUSH_REQUIRED] = "DF_FLUSH is required", [SEV_RET_INVALID_GUEST] = "Guest handle is invalid", [SEV_RET_INVALID_COMMAND] = "Invalid command", [SEV_RET_ACTIVE] = "Guest is active", [SEV_RET_HWSEV_RET_PLATFORM] = "Hardware error", [SEV_RET_HWSEV_RET_UNSAFE] = "Hardware unsafe", [SEV_RET_UNSUPPORTED] = "Feature not supported", [SEV_RET_INVALID_PARAM] = "Invalid parameter", [SEV_RET_RESOURCE_LIMIT] = "Required firmware resource depleted", [SEV_RET_SECURE_DATA_INVALID] = "Part-specific integrity check failure", }; #define SEV_FW_MAX_ERROR ARRAY_SIZE(sev_fw_errlist) /* doesn't expose this, so re-use the max from kvm.c */ #define KVM_MAX_CPUID_ENTRIES 100 typedef struct KvmCpuidInfo { struct kvm_cpuid2 cpuid; struct kvm_cpuid_entry2 entries[KVM_MAX_CPUID_ENTRIES]; } KvmCpuidInfo; #define SNP_CPUID_FUNCTION_MAXCOUNT 64 #define SNP_CPUID_FUNCTION_UNKNOWN 0xFFFFFFFF typedef struct { uint32_t eax_in; uint32_t ecx_in; uint64_t xcr0_in; uint64_t xss_in; uint32_t eax; uint32_t ebx; uint32_t ecx; uint32_t edx; uint64_t reserved; } __attribute__((packed)) SnpCpuidFunc; typedef struct { uint32_t count; uint32_t reserved1; uint64_t reserved2; SnpCpuidFunc entries[SNP_CPUID_FUNCTION_MAXCOUNT]; } __attribute__((packed)) SnpCpuidInfo; static int sev_ioctl(int fd, int cmd, void *data, int *error) { int r; struct kvm_sev_cmd input; memset(&input, 0x0, sizeof(input)); input.id = cmd; input.sev_fd = fd; input.data = (uintptr_t)data; r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, &input); if (error) { *error = input.error; } return r; } static int sev_platform_ioctl(int fd, int cmd, void *data, int *error) { int r; struct sev_issue_cmd arg; arg.cmd = cmd; arg.data = (unsigned long)data; r = ioctl(fd, SEV_ISSUE_CMD, &arg); if (error) { *error = arg.error; } return r; } static const char * fw_error_to_str(int code) { if (code < 0 || code >= SEV_FW_MAX_ERROR) { return "unknown error"; } return sev_fw_errlist[code]; } static bool sev_check_state(const SevCommonState *sev_common, SevState state) { assert(sev_common); return sev_common->state == state ? true : false; } static void sev_set_guest_state(SevCommonState *sev_common, SevState new_state) { assert(new_state < SEV_STATE__MAX); assert(sev_common); trace_kvm_sev_change_state(SevState_str(sev_common->state), SevState_str(new_state)); sev_common->state = new_state; } static void sev_ram_block_added(RAMBlockNotifier *n, void *host, size_t size, size_t max_size) { int r; struct kvm_enc_region range; ram_addr_t offset; MemoryRegion *mr; /* * The RAM device presents a memory region that should be treated * as IO region and should not be pinned. */ mr = memory_region_from_host(host, &offset); if (mr && memory_region_is_ram_device(mr)) { return; } range.addr = (uintptr_t)host; range.size = max_size; trace_kvm_memcrypt_register_region(host, max_size); r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_REG_REGION, &range); if (r) { error_report("%s: failed to register region (%p+%#zx) error '%s'", __func__, host, max_size, strerror(errno)); exit(1); } } static void sev_ram_block_removed(RAMBlockNotifier *n, void *host, size_t size, size_t max_size) { int r; struct kvm_enc_region range; ram_addr_t offset; MemoryRegion *mr; /* * The RAM device presents a memory region that should be treated * as IO region and should not have been pinned. */ mr = memory_region_from_host(host, &offset); if (mr && memory_region_is_ram_device(mr)) { return; } range.addr = (uintptr_t)host; range.size = max_size; trace_kvm_memcrypt_unregister_region(host, max_size); r = kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_UNREG_REGION, &range); if (r) { error_report("%s: failed to unregister region (%p+%#zx)", __func__, host, max_size); } } static struct RAMBlockNotifier sev_ram_notifier = { .ram_block_added = sev_ram_block_added, .ram_block_removed = sev_ram_block_removed, }; bool sev_enabled(void) { ConfidentialGuestSupport *cgs = MACHINE(qdev_get_machine())->cgs; return !!object_dynamic_cast(OBJECT(cgs), TYPE_SEV_COMMON); } bool sev_snp_enabled(void) { ConfidentialGuestSupport *cgs = MACHINE(qdev_get_machine())->cgs; return !!object_dynamic_cast(OBJECT(cgs), TYPE_SEV_SNP_GUEST); } bool sev_es_enabled(void) { ConfidentialGuestSupport *cgs = MACHINE(qdev_get_machine())->cgs; return sev_snp_enabled() || (sev_enabled() && SEV_GUEST(cgs)->policy & SEV_POLICY_ES); } uint32_t sev_get_cbit_position(void) { SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); return sev_common ? sev_common->cbitpos : 0; } uint32_t sev_get_reduced_phys_bits(void) { SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); return sev_common ? sev_common->reduced_phys_bits : 0; } static SevInfo *sev_get_info(void) { SevInfo *info; SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); info = g_new0(SevInfo, 1); info->enabled = sev_enabled(); if (info->enabled) { info->api_major = sev_common->api_major; info->api_minor = sev_common->api_minor; info->build_id = sev_common->build_id; info->state = sev_common->state; if (sev_snp_enabled()) { info->sev_type = SEV_GUEST_TYPE_SEV_SNP; info->u.sev_snp.snp_policy = object_property_get_uint(OBJECT(sev_common), "policy", NULL); } else { info->sev_type = SEV_GUEST_TYPE_SEV; info->u.sev.handle = SEV_GUEST(sev_common)->handle; info->u.sev.policy = (uint32_t)object_property_get_uint(OBJECT(sev_common), "policy", NULL); } } return info; } SevInfo *qmp_query_sev(Error **errp) { SevInfo *info; info = sev_get_info(); if (!info) { error_setg(errp, "SEV feature is not available"); return NULL; } return info; } void hmp_info_sev(Monitor *mon, const QDict *qdict) { SevInfo *info = sev_get_info(); if (!info || !info->enabled) { monitor_printf(mon, "SEV is not enabled\n"); goto out; } monitor_printf(mon, "SEV type: %s\n", SevGuestType_str(info->sev_type)); monitor_printf(mon, "state: %s\n", SevState_str(info->state)); monitor_printf(mon, "build: %d\n", info->build_id); monitor_printf(mon, "api version: %d.%d\n", info->api_major, info->api_minor); if (sev_snp_enabled()) { monitor_printf(mon, "debug: %s\n", info->u.sev_snp.snp_policy & SEV_SNP_POLICY_DBG ? "on" : "off"); monitor_printf(mon, "SMT allowed: %s\n", info->u.sev_snp.snp_policy & SEV_SNP_POLICY_SMT ? "on" : "off"); } else { monitor_printf(mon, "handle: %d\n", info->u.sev.handle); monitor_printf(mon, "debug: %s\n", info->u.sev.policy & SEV_POLICY_NODBG ? "off" : "on"); monitor_printf(mon, "key-sharing: %s\n", info->u.sev.policy & SEV_POLICY_NOKS ? "off" : "on"); } out: qapi_free_SevInfo(info); } static int sev_get_pdh_info(int fd, guchar **pdh, size_t *pdh_len, guchar **cert_chain, size_t *cert_chain_len, Error **errp) { guchar *pdh_data = NULL; guchar *cert_chain_data = NULL; struct sev_user_data_pdh_cert_export export = {}; int err, r; /* query the certificate length */ r = sev_platform_ioctl(fd, SEV_PDH_CERT_EXPORT, &export, &err); if (r < 0) { if (err != SEV_RET_INVALID_LEN) { error_setg(errp, "SEV: Failed to export PDH cert" " ret=%d fw_err=%d (%s)", r, err, fw_error_to_str(err)); return 1; } } pdh_data = g_new(guchar, export.pdh_cert_len); cert_chain_data = g_new(guchar, export.cert_chain_len); export.pdh_cert_address = (unsigned long)pdh_data; export.cert_chain_address = (unsigned long)cert_chain_data; r = sev_platform_ioctl(fd, SEV_PDH_CERT_EXPORT, &export, &err); if (r < 0) { error_setg(errp, "SEV: Failed to export PDH cert ret=%d fw_err=%d (%s)", r, err, fw_error_to_str(err)); goto e_free; } *pdh = pdh_data; *pdh_len = export.pdh_cert_len; *cert_chain = cert_chain_data; *cert_chain_len = export.cert_chain_len; return 0; e_free: g_free(pdh_data); g_free(cert_chain_data); return 1; } static int sev_get_cpu0_id(int fd, guchar **id, size_t *id_len, Error **errp) { guchar *id_data; struct sev_user_data_get_id2 get_id2 = {}; int err, r; /* query the ID length */ r = sev_platform_ioctl(fd, SEV_GET_ID2, &get_id2, &err); if (r < 0 && err != SEV_RET_INVALID_LEN) { error_setg(errp, "SEV: Failed to get ID ret=%d fw_err=%d (%s)", r, err, fw_error_to_str(err)); return 1; } id_data = g_new(guchar, get_id2.length); get_id2.address = (unsigned long)id_data; r = sev_platform_ioctl(fd, SEV_GET_ID2, &get_id2, &err); if (r < 0) { error_setg(errp, "SEV: Failed to get ID ret=%d fw_err=%d (%s)", r, err, fw_error_to_str(err)); goto err; } *id = id_data; *id_len = get_id2.length; return 0; err: g_free(id_data); return 1; } static SevCapability *sev_get_capabilities(Error **errp) { SevCapability *cap = NULL; guchar *pdh_data = NULL; guchar *cert_chain_data = NULL; guchar *cpu0_id_data = NULL; size_t pdh_len = 0, cert_chain_len = 0, cpu0_id_len = 0; uint32_t ebx; int fd; SevCommonState *sev_common; char *sev_device; if (!kvm_enabled()) { error_setg(errp, "KVM not enabled"); return NULL; } if (kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, NULL) < 0) { error_setg(errp, "SEV is not enabled in KVM"); return NULL; } sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); if (!sev_common) { error_setg(errp, "SEV is not configured"); } sev_device = object_property_get_str(OBJECT(sev_common), "sev-device", &error_abort); fd = open(sev_device, O_RDWR); if (fd < 0) { error_setg_errno(errp, errno, "SEV: Failed to open %s", DEFAULT_SEV_DEVICE); g_free(sev_device); return NULL; } g_free(sev_device); if (sev_get_pdh_info(fd, &pdh_data, &pdh_len, &cert_chain_data, &cert_chain_len, errp)) { goto out; } if (sev_get_cpu0_id(fd, &cpu0_id_data, &cpu0_id_len, errp)) { goto out; } cap = g_new0(SevCapability, 1); cap->pdh = g_base64_encode(pdh_data, pdh_len); cap->cert_chain = g_base64_encode(cert_chain_data, cert_chain_len); cap->cpu0_id = g_base64_encode(cpu0_id_data, cpu0_id_len); host_cpuid(0x8000001F, 0, NULL, &ebx, NULL, NULL); cap->cbitpos = ebx & 0x3f; /* * When SEV feature is enabled, we loose one bit in guest physical * addressing. */ cap->reduced_phys_bits = 1; out: g_free(cpu0_id_data); g_free(pdh_data); g_free(cert_chain_data); close(fd); return cap; } SevCapability *qmp_query_sev_capabilities(Error **errp) { return sev_get_capabilities(errp); } static OvmfSevMetadata *ovmf_sev_metadata_table; #define OVMF_SEV_META_DATA_GUID "dc886566-984a-4798-A75e-5585a7bf67cc" typedef struct __attribute__((__packed__)) OvmfSevMetadataOffset { uint32_t offset; } OvmfSevMetadataOffset; OvmfSevMetadata *pc_system_get_ovmf_sev_metadata_ptr(void) { return ovmf_sev_metadata_table; } void pc_system_parse_sev_metadata(uint8_t *flash_ptr, size_t flash_size) { OvmfSevMetadata *metadata; OvmfSevMetadataOffset *data; if (!pc_system_ovmf_table_find(OVMF_SEV_META_DATA_GUID, (uint8_t **)&data, NULL)) { return; } metadata = (OvmfSevMetadata *)(flash_ptr + flash_size - data->offset); if (memcmp(metadata->signature, "ASEV", 4) != 0 || metadata->len < sizeof(OvmfSevMetadata) || metadata->len > flash_size - data->offset) { return; } ovmf_sev_metadata_table = g_memdup2(metadata, metadata->len); } static SevAttestationReport *sev_get_attestation_report(const char *mnonce, Error **errp) { struct kvm_sev_attestation_report input = {}; SevAttestationReport *report = NULL; SevCommonState *sev_common; g_autofree guchar *data = NULL; g_autofree guchar *buf = NULL; gsize len; int err = 0, ret; if (!sev_enabled()) { error_setg(errp, "SEV is not enabled"); return NULL; } /* lets decode the mnonce string */ buf = g_base64_decode(mnonce, &len); if (!buf) { error_setg(errp, "SEV: failed to decode mnonce input"); return NULL; } /* verify the input mnonce length */ if (len != sizeof(input.mnonce)) { error_setg(errp, "SEV: mnonce must be %zu bytes (got %" G_GSIZE_FORMAT ")", sizeof(input.mnonce), len); return NULL; } sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); /* Query the report length */ ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_GET_ATTESTATION_REPORT, &input, &err); if (ret < 0) { if (err != SEV_RET_INVALID_LEN) { error_setg(errp, "SEV: Failed to query the attestation report" " length ret=%d fw_err=%d (%s)", ret, err, fw_error_to_str(err)); return NULL; } } data = g_malloc(input.len); input.uaddr = (unsigned long)data; memcpy(input.mnonce, buf, sizeof(input.mnonce)); /* Query the report */ ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_GET_ATTESTATION_REPORT, &input, &err); if (ret) { error_setg_errno(errp, errno, "SEV: Failed to get attestation report" " ret=%d fw_err=%d (%s)", ret, err, fw_error_to_str(err)); return NULL; } report = g_new0(SevAttestationReport, 1); report->data = g_base64_encode(data, input.len); trace_kvm_sev_attestation_report(mnonce, report->data); return report; } SevAttestationReport *qmp_query_sev_attestation_report(const char *mnonce, Error **errp) { return sev_get_attestation_report(mnonce, errp); } static int sev_read_file_base64(const char *filename, guchar **data, gsize *len) { gsize sz; g_autofree gchar *base64 = NULL; GError *error = NULL; if (!g_file_get_contents(filename, &base64, &sz, &error)) { error_report("SEV: Failed to read '%s' (%s)", filename, error->message); g_error_free(error); return -1; } *data = g_base64_decode(base64, len); return 0; } static int sev_snp_launch_start(SevCommonState *sev_common) { int fw_error, rc; SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(sev_common); struct kvm_sev_snp_launch_start *start = &sev_snp_guest->kvm_start_conf; trace_kvm_sev_snp_launch_start(start->policy, sev_snp_guest->guest_visible_workarounds); if (!kvm_enable_hypercall(BIT_ULL(KVM_HC_MAP_GPA_RANGE))) { return 1; } rc = sev_ioctl(sev_common->sev_fd, KVM_SEV_SNP_LAUNCH_START, start, &fw_error); if (rc < 0) { error_report("%s: SNP_LAUNCH_START ret=%d fw_error=%d '%s'", __func__, rc, fw_error, fw_error_to_str(fw_error)); return 1; } QTAILQ_INIT(&launch_update); sev_set_guest_state(sev_common, SEV_STATE_LAUNCH_UPDATE); return 0; } static int sev_launch_start(SevCommonState *sev_common) { gsize sz; int ret = 1; int fw_error, rc; SevGuestState *sev_guest = SEV_GUEST(sev_common); struct kvm_sev_launch_start start = { .handle = sev_guest->handle, .policy = sev_guest->policy }; guchar *session = NULL, *dh_cert = NULL; if (sev_guest->session_file) { if (sev_read_file_base64(sev_guest->session_file, &session, &sz) < 0) { goto out; } start.session_uaddr = (unsigned long)session; start.session_len = sz; } if (sev_guest->dh_cert_file) { if (sev_read_file_base64(sev_guest->dh_cert_file, &dh_cert, &sz) < 0) { goto out; } start.dh_uaddr = (unsigned long)dh_cert; start.dh_len = sz; } trace_kvm_sev_launch_start(start.policy, session, dh_cert); rc = sev_ioctl(sev_common->sev_fd, KVM_SEV_LAUNCH_START, &start, &fw_error); if (rc < 0) { error_report("%s: LAUNCH_START ret=%d fw_error=%d '%s'", __func__, ret, fw_error, fw_error_to_str(fw_error)); goto out; } sev_set_guest_state(sev_common, SEV_STATE_LAUNCH_UPDATE); sev_guest->handle = start.handle; ret = 0; out: g_free(session); g_free(dh_cert); return ret; } static void sev_snp_cpuid_report_mismatches(SnpCpuidInfo *old, SnpCpuidInfo *new) { size_t i; if (old->count != new->count) { error_report("SEV-SNP: CPUID validation failed due to count mismatch," "provided: %d, expected: %d", old->count, new->count); return; } for (i = 0; i < old->count; i++) { SnpCpuidFunc *old_func, *new_func; old_func = &old->entries[i]; new_func = &new->entries[i]; if (memcmp(old_func, new_func, sizeof(SnpCpuidFunc))) { error_report("SEV-SNP: CPUID validation failed for function 0x%x, index: 0x%x" "provided: eax:0x%08x, ebx: 0x%08x, ecx: 0x%08x, edx: 0x%08x" "expected: eax:0x%08x, ebx: 0x%08x, ecx: 0x%08x, edx: 0x%08x", old_func->eax_in, old_func->ecx_in, old_func->eax, old_func->ebx, old_func->ecx, old_func->edx, new_func->eax, new_func->ebx, new_func->ecx, new_func->edx); } } } static const char * snp_page_type_to_str(int type) { switch (type) { case KVM_SEV_SNP_PAGE_TYPE_NORMAL: return "Normal"; case KVM_SEV_SNP_PAGE_TYPE_ZERO: return "Zero"; case KVM_SEV_SNP_PAGE_TYPE_UNMEASURED: return "Unmeasured"; case KVM_SEV_SNP_PAGE_TYPE_SECRETS: return "Secrets"; case KVM_SEV_SNP_PAGE_TYPE_CPUID: return "Cpuid"; default: return "unknown"; } } static int sev_snp_launch_update(SevSnpGuestState *sev_snp_guest, SevLaunchUpdateData *data) { int ret, fw_error; SnpCpuidInfo snp_cpuid_info; struct kvm_sev_snp_launch_update update = {0}; if (!data->hva || !data->len) { error_report("SNP_LAUNCH_UPDATE called with invalid address" "/ length: %p / %lx", data->hva, data->len); return 1; } if (data->type == KVM_SEV_SNP_PAGE_TYPE_CPUID) { /* Save a copy for comparison in case the LAUNCH_UPDATE fails */ memcpy(&snp_cpuid_info, data->hva, sizeof(snp_cpuid_info)); } update.uaddr = (__u64)(unsigned long)data->hva; update.gfn_start = data->gpa >> TARGET_PAGE_BITS; update.len = data->len; update.type = data->type; /* * KVM_SEV_SNP_LAUNCH_UPDATE requires that GPA ranges have the private * memory attribute set in advance. */ ret = kvm_set_memory_attributes_private(data->gpa, data->len); if (ret) { error_report("SEV-SNP: failed to configure initial" "private guest memory"); goto out; } while (update.len || ret == -EAGAIN) { trace_kvm_sev_snp_launch_update(update.uaddr, update.gfn_start << TARGET_PAGE_BITS, update.len, snp_page_type_to_str(update.type)); ret = sev_ioctl(SEV_COMMON(sev_snp_guest)->sev_fd, KVM_SEV_SNP_LAUNCH_UPDATE, &update, &fw_error); if (ret && ret != -EAGAIN) { error_report("SNP_LAUNCH_UPDATE ret=%d fw_error=%d '%s'", ret, fw_error, fw_error_to_str(fw_error)); if (data->type == KVM_SEV_SNP_PAGE_TYPE_CPUID) { sev_snp_cpuid_report_mismatches(&snp_cpuid_info, data->hva); error_report("SEV-SNP: failed update CPUID page"); } break; } } out: if (!ret && update.gfn_start << TARGET_PAGE_BITS != data->gpa + data->len) { error_report("SEV-SNP: expected update of GPA range %lx-%lx," "got GPA range %lx-%llx", data->gpa, data->gpa + data->len, data->gpa, update.gfn_start << TARGET_PAGE_BITS); ret = -EIO; } return ret; } static int sev_launch_update_data(SevCommonState *sev_common, hwaddr gpa, uint8_t *addr, uint64_t len) { int ret, fw_error; struct kvm_sev_launch_update_data update; if (!addr || !len) { return 1; } update.uaddr = (uintptr_t)addr; update.len = len; trace_kvm_sev_launch_update_data(addr, len); ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_LAUNCH_UPDATE_DATA, &update, &fw_error); if (ret) { error_report("%s: LAUNCH_UPDATE ret=%d fw_error=%d '%s'", __func__, ret, fw_error, fw_error_to_str(fw_error)); } return ret; } static int sev_launch_update_vmsa(SevGuestState *sev_guest) { int ret, fw_error; ret = sev_ioctl(SEV_COMMON(sev_guest)->sev_fd, KVM_SEV_LAUNCH_UPDATE_VMSA, NULL, &fw_error); if (ret) { error_report("%s: LAUNCH_UPDATE_VMSA ret=%d fw_error=%d '%s'", __func__, ret, fw_error, fw_error_to_str(fw_error)); } return ret; } static void sev_launch_get_measure(Notifier *notifier, void *unused) { SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); SevGuestState *sev_guest = SEV_GUEST(sev_common); int ret, error; g_autofree guchar *data = NULL; struct kvm_sev_launch_measure measurement = {}; if (!sev_check_state(sev_common, SEV_STATE_LAUNCH_UPDATE)) { return; } if (sev_es_enabled()) { /* measure all the VM save areas before getting launch_measure */ ret = sev_launch_update_vmsa(sev_guest); if (ret) { exit(1); } kvm_mark_guest_state_protected(); } /* query the measurement blob length */ ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_LAUNCH_MEASURE, &measurement, &error); if (!measurement.len) { error_report("%s: LAUNCH_MEASURE ret=%d fw_error=%d '%s'", __func__, ret, error, fw_error_to_str(errno)); return; } data = g_new0(guchar, measurement.len); measurement.uaddr = (unsigned long)data; /* get the measurement blob */ ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_LAUNCH_MEASURE, &measurement, &error); if (ret) { error_report("%s: LAUNCH_MEASURE ret=%d fw_error=%d '%s'", __func__, ret, error, fw_error_to_str(errno)); return; } sev_set_guest_state(sev_common, SEV_STATE_LAUNCH_SECRET); /* encode the measurement value and emit the event */ sev_guest->measurement = g_base64_encode(data, measurement.len); trace_kvm_sev_launch_measurement(sev_guest->measurement); } static char *sev_get_launch_measurement(void) { ConfidentialGuestSupport *cgs = MACHINE(qdev_get_machine())->cgs; SevGuestState *sev_guest = (SevGuestState *)object_dynamic_cast(OBJECT(cgs), TYPE_SEV_GUEST); if (sev_guest && SEV_COMMON(sev_guest)->state >= SEV_STATE_LAUNCH_SECRET) { return g_strdup(sev_guest->measurement); } return NULL; } SevLaunchMeasureInfo *qmp_query_sev_launch_measure(Error **errp) { char *data; SevLaunchMeasureInfo *info; data = sev_get_launch_measurement(); if (!data) { error_setg(errp, "SEV launch measurement is not available"); return NULL; } info = g_malloc0(sizeof(*info)); info->data = data; return info; } static Notifier sev_machine_done_notify = { .notify = sev_launch_get_measure, }; static void sev_launch_finish(SevCommonState *sev_common) { int ret, error; trace_kvm_sev_launch_finish(); ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_LAUNCH_FINISH, 0, &error); if (ret) { error_report("%s: LAUNCH_FINISH ret=%d fw_error=%d '%s'", __func__, ret, error, fw_error_to_str(error)); exit(1); } sev_set_guest_state(sev_common, SEV_STATE_RUNNING); /* add migration blocker */ error_setg(&sev_mig_blocker, "SEV: Migration is not implemented"); migrate_add_blocker(&sev_mig_blocker, &error_fatal); } static int snp_launch_update_data(uint64_t gpa, void *hva, uint32_t len, int type) { SevLaunchUpdateData *data; data = g_new0(SevLaunchUpdateData, 1); data->gpa = gpa; data->hva = hva; data->len = len; data->type = type; QTAILQ_INSERT_TAIL(&launch_update, data, next); return 0; } static int sev_snp_launch_update_data(SevCommonState *sev_common, hwaddr gpa, uint8_t *ptr, uint64_t len) { int ret = snp_launch_update_data(gpa, ptr, len, KVM_SEV_SNP_PAGE_TYPE_NORMAL); return ret; } static int sev_snp_cpuid_info_fill(SnpCpuidInfo *snp_cpuid_info, const KvmCpuidInfo *kvm_cpuid_info) { size_t i; if (kvm_cpuid_info->cpuid.nent > SNP_CPUID_FUNCTION_MAXCOUNT) { error_report("SEV-SNP: CPUID entry count (%d) exceeds max (%d)", kvm_cpuid_info->cpuid.nent, SNP_CPUID_FUNCTION_MAXCOUNT); return -1; } memset(snp_cpuid_info, 0, sizeof(*snp_cpuid_info)); for (i = 0; i < kvm_cpuid_info->cpuid.nent; i++) { const struct kvm_cpuid_entry2 *kvm_cpuid_entry; SnpCpuidFunc *snp_cpuid_entry; kvm_cpuid_entry = &kvm_cpuid_info->entries[i]; snp_cpuid_entry = &snp_cpuid_info->entries[i]; snp_cpuid_entry->eax_in = kvm_cpuid_entry->function; if (kvm_cpuid_entry->flags == KVM_CPUID_FLAG_SIGNIFCANT_INDEX) { snp_cpuid_entry->ecx_in = kvm_cpuid_entry->index; } snp_cpuid_entry->eax = kvm_cpuid_entry->eax; snp_cpuid_entry->ebx = kvm_cpuid_entry->ebx; snp_cpuid_entry->ecx = kvm_cpuid_entry->ecx; snp_cpuid_entry->edx = kvm_cpuid_entry->edx; /* * Guest kernels will calculate EBX themselves using the 0xD * subfunctions corresponding to the individual XSAVE areas, so only * encode the base XSAVE size in the initial leaves, corresponding * to the initial XCR0=1 state. */ if (snp_cpuid_entry->eax_in == 0xD && (snp_cpuid_entry->ecx_in == 0x0 || snp_cpuid_entry->ecx_in == 0x1)) { snp_cpuid_entry->ebx = 0x240; snp_cpuid_entry->xcr0_in = 1; snp_cpuid_entry->xss_in = 0; } } snp_cpuid_info->count = i; return 0; } static int snp_launch_update_cpuid(uint32_t cpuid_addr, void *hva, uint32_t cpuid_len) { KvmCpuidInfo kvm_cpuid_info = {0}; SnpCpuidInfo snp_cpuid_info; CPUState *cs = first_cpu; int ret; uint32_t i = 0; assert(sizeof(snp_cpuid_info) <= cpuid_len); /* get the cpuid list from KVM */ do { kvm_cpuid_info.cpuid.nent = ++i; ret = kvm_vcpu_ioctl(cs, KVM_GET_CPUID2, &kvm_cpuid_info); } while (ret == -E2BIG); if (ret) { error_report("SEV-SNP: unable to query CPUID values for CPU: '%s'", strerror(-ret)); return 1; } ret = sev_snp_cpuid_info_fill(&snp_cpuid_info, &kvm_cpuid_info); if (ret) { error_report("SEV-SNP: failed to generate CPUID table information"); return 1; } memcpy(hva, &snp_cpuid_info, sizeof(snp_cpuid_info)); return snp_launch_update_data(cpuid_addr, hva, 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) { switch (desc_type) { /* Add the umeasured prevalidated pages as a zero page */ case SEV_DESC_TYPE_SNP_SEC_MEM: return KVM_SEV_SNP_PAGE_TYPE_ZERO; case SEV_DESC_TYPE_SNP_SECRETS: return KVM_SEV_SNP_PAGE_TYPE_SECRETS; case SEV_DESC_TYPE_CPUID: return KVM_SEV_SNP_PAGE_TYPE_CPUID; default: return KVM_SEV_SNP_PAGE_TYPE_ZERO; } } static void snp_populate_metadata_pages(SevSnpGuestState *sev_snp, OvmfSevMetadata *metadata) { OvmfSevMetadataDesc *desc; int type, ret, i; void *hva; MemoryRegion *mr = NULL; for (i = 0; i < metadata->num_desc; i++) { desc = &metadata->descs[i]; type = snp_metadata_desc_to_page_type(desc->type); hva = gpa2hva(&mr, desc->base, desc->len, NULL); if (!hva) { error_report("%s: Failed to get HVA for GPA 0x%x sz 0x%x", __func__, desc->base, desc->len); exit(1); } 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); } if (ret) { error_report("%s: Failed to add metadata page gpa 0x%x+%x type %d", __func__, desc->base, desc->len, desc->type); exit(1); } } } static void sev_snp_launch_finish(SevCommonState *sev_common) { int ret, error; Error *local_err = NULL; OvmfSevMetadata *metadata; SevLaunchUpdateData *data; SevSnpGuestState *sev_snp = SEV_SNP_GUEST(sev_common); struct kvm_sev_snp_launch_finish *finish = &sev_snp->kvm_finish_conf; /* * To boot the SNP guest, the hypervisor is required to populate the CPUID * and Secrets page before finalizing the launch flow. The location of * the secrets and CPUID page is available through the OVMF metadata GUID. */ metadata = pc_system_get_ovmf_sev_metadata_ptr(); if (metadata == NULL) { error_report("%s: Failed to locate SEV metadata header", __func__); exit(1); } /* Populate all the metadata pages */ snp_populate_metadata_pages(sev_snp, metadata); QTAILQ_FOREACH(data, &launch_update, next) { ret = sev_snp_launch_update(sev_snp, data); if (ret) { exit(1); } } trace_kvm_sev_snp_launch_finish(sev_snp->id_block, sev_snp->id_auth, sev_snp->host_data); ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_SNP_LAUNCH_FINISH, finish, &error); if (ret) { error_report("SNP_LAUNCH_FINISH ret=%d fw_error=%d '%s'", ret, error, fw_error_to_str(error)); exit(1); } kvm_mark_guest_state_protected(); sev_set_guest_state(sev_common, SEV_STATE_RUNNING); /* add migration blocker */ error_setg(&sev_mig_blocker, "SEV-SNP: Migration is not implemented"); ret = migrate_add_blocker(&sev_mig_blocker, &local_err); if (local_err) { error_report_err(local_err); error_free(sev_mig_blocker); exit(1); } } static void sev_vm_state_change(void *opaque, bool running, RunState state) { SevCommonState *sev_common = opaque; SevCommonStateClass *klass = SEV_COMMON_GET_CLASS(opaque); if (running) { if (!sev_check_state(sev_common, SEV_STATE_RUNNING)) { klass->launch_finish(sev_common); } } } static int sev_kvm_type(X86ConfidentialGuest *cg) { SevCommonState *sev_common = SEV_COMMON(cg); SevGuestState *sev_guest = SEV_GUEST(sev_common); int kvm_type; if (sev_common->kvm_type != -1) { goto out; } kvm_type = (sev_guest->policy & SEV_POLICY_ES) ? KVM_X86_SEV_ES_VM : KVM_X86_SEV_VM; if (kvm_is_vm_type_supported(kvm_type) && !sev_guest->legacy_vm_type) { sev_common->kvm_type = kvm_type; } else { sev_common->kvm_type = KVM_X86_DEFAULT_VM; } out: return sev_common->kvm_type; } static int sev_snp_kvm_type(X86ConfidentialGuest *cg) { return KVM_X86_SNP_VM; } static int sev_common_kvm_init(ConfidentialGuestSupport *cgs, Error **errp) { char *devname; int ret, fw_error, cmd; uint32_t ebx; uint32_t host_cbitpos; struct sev_user_data_status status = {}; SevCommonState *sev_common = SEV_COMMON(cgs); SevCommonStateClass *klass = SEV_COMMON_GET_CLASS(cgs); X86ConfidentialGuestClass *x86_klass = X86_CONFIDENTIAL_GUEST_GET_CLASS(cgs); sev_common->state = SEV_STATE_UNINIT; host_cpuid(0x8000001F, 0, NULL, &ebx, NULL, NULL); host_cbitpos = ebx & 0x3f; /* * The cbitpos value will be placed in bit positions 5:0 of the EBX * register of CPUID 0x8000001F. No need to verify the range as the * comparison against the host value accomplishes that. */ if (host_cbitpos != sev_common->cbitpos) { error_setg(errp, "%s: cbitpos check failed, host '%d' requested '%d'", __func__, host_cbitpos, sev_common->cbitpos); return -1; } /* * The reduced-phys-bits value will be placed in bit positions 11:6 of * the EBX register of CPUID 0x8000001F, so verify the supplied value * is in the range of 1 to 63. */ if (sev_common->reduced_phys_bits < 1 || sev_common->reduced_phys_bits > 63) { error_setg(errp, "%s: reduced_phys_bits check failed," " it should be in the range of 1 to 63, requested '%d'", __func__, sev_common->reduced_phys_bits); return -1; } devname = object_property_get_str(OBJECT(sev_common), "sev-device", NULL); sev_common->sev_fd = open(devname, O_RDWR); if (sev_common->sev_fd < 0) { error_setg(errp, "%s: Failed to open %s '%s'", __func__, devname, strerror(errno)); g_free(devname); return -1; } g_free(devname); ret = sev_platform_ioctl(sev_common->sev_fd, SEV_PLATFORM_STATUS, &status, &fw_error); if (ret) { error_setg(errp, "%s: failed to get platform status ret=%d " "fw_error='%d: %s'", __func__, ret, fw_error, fw_error_to_str(fw_error)); return -1; } sev_common->build_id = status.build; sev_common->api_major = status.api_major; sev_common->api_minor = status.api_minor; if (sev_es_enabled()) { if (!kvm_kernel_irqchip_allowed()) { error_setg(errp, "%s: SEV-ES guests require in-kernel irqchip" "support", __func__); return -1; } } if (sev_es_enabled() && !sev_snp_enabled()) { if (!(status.flags & SEV_STATUS_FLAGS_CONFIG_ES)) { error_setg(errp, "%s: guest policy requires SEV-ES, but " "host SEV-ES support unavailable", __func__); return -1; } } trace_kvm_sev_init(); if (x86_klass->kvm_type(X86_CONFIDENTIAL_GUEST(sev_common)) == KVM_X86_DEFAULT_VM) { cmd = sev_es_enabled() ? KVM_SEV_ES_INIT : KVM_SEV_INIT; ret = sev_ioctl(sev_common->sev_fd, cmd, NULL, &fw_error); } else { struct kvm_sev_init args = { 0 }; ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_INIT2, &args, &fw_error); } if (ret) { error_setg(errp, "%s: failed to initialize ret=%d fw_error=%d '%s'", __func__, ret, fw_error, fw_error_to_str(fw_error)); return -1; } ret = klass->launch_start(sev_common); if (ret) { error_setg(errp, "%s: failed to create encryption context", __func__); return -1; } if (klass->kvm_init && klass->kvm_init(cgs, errp)) { return -1; } qemu_add_vm_change_state_handler(sev_vm_state_change, sev_common); cgs->ready = true; return 0; } static int sev_kvm_init(ConfidentialGuestSupport *cgs, Error **errp) { int ret; /* * SEV/SEV-ES rely on pinned memory to back guest RAM so discarding * isn't actually possible. With SNP, only guest_memfd pages are used * for private guest memory, so discarding of shared memory is still * possible.. */ ret = ram_block_discard_disable(true); if (ret) { error_setg(errp, "%s: cannot disable RAM discard", __func__); return -1; } /* * SEV uses these notifiers to register/pin pages prior to guest use, * but SNP relies on guest_memfd for private pages, which has its * own internal mechanisms for registering/pinning private memory. */ ram_block_notifier_add(&sev_ram_notifier); /* * The machine done notify event is used for SEV guests to get the * measurement of the encrypted images. When SEV-SNP is enabled, the * measurement is part of the guest attestation process where it can * be collected without any reliance on the VMM. So skip registering * the notifier for SNP in favor of using guest attestation instead. */ qemu_add_machine_init_done_notifier(&sev_machine_done_notify); return 0; } static int sev_snp_kvm_init(ConfidentialGuestSupport *cgs, Error **errp) { MachineState *ms = MACHINE(qdev_get_machine()); X86MachineState *x86ms = X86_MACHINE(ms); if (x86ms->smm == ON_OFF_AUTO_AUTO) { x86ms->smm = ON_OFF_AUTO_OFF; } else if (x86ms->smm == ON_OFF_AUTO_ON) { error_setg(errp, "SEV-SNP does not support SMM."); return -1; } return 0; } int sev_encrypt_flash(hwaddr gpa, uint8_t *ptr, uint64_t len, Error **errp) { SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); SevCommonStateClass *klass = SEV_COMMON_GET_CLASS(sev_common); if (!sev_common) { return 0; } /* if SEV is in update state then encrypt the data else do nothing */ if (sev_check_state(sev_common, SEV_STATE_LAUNCH_UPDATE)) { int ret; ret = klass->launch_update_data(sev_common, gpa, ptr, len); if (ret < 0) { error_setg(errp, "SEV: Failed to encrypt pflash rom"); return ret; } } return 0; } int sev_inject_launch_secret(const char *packet_hdr, const char *secret, uint64_t gpa, Error **errp) { ERRP_GUARD(); struct kvm_sev_launch_secret input; g_autofree guchar *data = NULL, *hdr = NULL; int error, ret = 1; void *hva; gsize hdr_sz = 0, data_sz = 0; MemoryRegion *mr = NULL; SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); if (!sev_common) { error_setg(errp, "SEV not enabled for guest"); return 1; } /* secret can be injected only in this state */ if (!sev_check_state(sev_common, SEV_STATE_LAUNCH_SECRET)) { error_setg(errp, "SEV: Not in correct state. (LSECRET) %x", sev_common->state); return 1; } hdr = g_base64_decode(packet_hdr, &hdr_sz); if (!hdr || !hdr_sz) { error_setg(errp, "SEV: Failed to decode sequence header"); return 1; } data = g_base64_decode(secret, &data_sz); if (!data || !data_sz) { error_setg(errp, "SEV: Failed to decode data"); return 1; } hva = gpa2hva(&mr, gpa, data_sz, errp); if (!hva) { error_prepend(errp, "SEV: Failed to calculate guest address: "); return 1; } input.hdr_uaddr = (uint64_t)(unsigned long)hdr; input.hdr_len = hdr_sz; input.trans_uaddr = (uint64_t)(unsigned long)data; input.trans_len = data_sz; input.guest_uaddr = (uint64_t)(unsigned long)hva; input.guest_len = data_sz; trace_kvm_sev_launch_secret(gpa, input.guest_uaddr, input.trans_uaddr, input.trans_len); ret = sev_ioctl(sev_common->sev_fd, KVM_SEV_LAUNCH_SECRET, &input, &error); if (ret) { error_setg(errp, "SEV: failed to inject secret ret=%d fw_error=%d '%s'", ret, error, fw_error_to_str(error)); return ret; } return 0; } #define SEV_SECRET_GUID "4c2eb361-7d9b-4cc3-8081-127c90d3d294" struct sev_secret_area { uint32_t base; uint32_t size; }; void qmp_sev_inject_launch_secret(const char *packet_hdr, const char *secret, bool has_gpa, uint64_t gpa, Error **errp) { if (!sev_enabled()) { error_setg(errp, "SEV not enabled for guest"); return; } if (!has_gpa) { uint8_t *data; struct sev_secret_area *area; if (!pc_system_ovmf_table_find(SEV_SECRET_GUID, &data, NULL)) { error_setg(errp, "SEV: no secret area found in OVMF," " gpa must be specified."); return; } area = (struct sev_secret_area *)data; gpa = area->base; } sev_inject_launch_secret(packet_hdr, secret, gpa, errp); } static int sev_es_parse_reset_block(SevInfoBlock *info, uint32_t *addr) { if (!info->reset_addr) { error_report("SEV-ES reset address is zero"); return 1; } *addr = info->reset_addr; return 0; } static int sev_es_find_reset_vector(void *flash_ptr, uint64_t flash_size, uint32_t *addr) { QemuUUID info_guid, *guid; SevInfoBlock *info; uint8_t *data; uint16_t *len; /* * Initialize the address to zero. An address of zero with a successful * return code indicates that SEV-ES is not active. */ *addr = 0; /* * Extract the AP reset vector for SEV-ES guests by locating the SEV GUID. * The SEV GUID is located on its own (original implementation) or within * the Firmware GUID Table (new implementation), either of which are * located 32 bytes from the end of the flash. * * Check the Firmware GUID Table first. */ if (pc_system_ovmf_table_find(SEV_INFO_BLOCK_GUID, &data, NULL)) { return sev_es_parse_reset_block((SevInfoBlock *)data, addr); } /* * SEV info block not found in the Firmware GUID Table (or there isn't * a Firmware GUID Table), fall back to the original implementation. */ data = flash_ptr + flash_size - 0x20; qemu_uuid_parse(SEV_INFO_BLOCK_GUID, &info_guid); info_guid = qemu_uuid_bswap(info_guid); /* GUIDs are LE */ guid = (QemuUUID *)(data - sizeof(info_guid)); if (!qemu_uuid_is_equal(guid, &info_guid)) { error_report("SEV information block/Firmware GUID Table block not found in pflash rom"); return 1; } len = (uint16_t *)((uint8_t *)guid - sizeof(*len)); info = (SevInfoBlock *)(data - le16_to_cpu(*len)); return sev_es_parse_reset_block(info, addr); } void sev_es_set_reset_vector(CPUState *cpu) { X86CPU *x86; CPUX86State *env; SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); /* Only update if we have valid reset information */ if (!sev_common || !sev_common->reset_data_valid) { return; } /* Do not update the BSP reset state */ if (cpu->cpu_index == 0) { return; } x86 = X86_CPU(cpu); env = &x86->env; cpu_x86_load_seg_cache(env, R_CS, 0xf000, sev_common->reset_cs, 0xffff, DESC_P_MASK | DESC_S_MASK | DESC_CS_MASK | DESC_R_MASK | DESC_A_MASK); env->eip = sev_common->reset_ip; } int sev_es_save_reset_vector(void *flash_ptr, uint64_t flash_size) { CPUState *cpu; uint32_t addr; int ret; SevCommonState *sev_common = SEV_COMMON(MACHINE(qdev_get_machine())->cgs); if (!sev_es_enabled()) { return 0; } addr = 0; ret = sev_es_find_reset_vector(flash_ptr, flash_size, &addr); if (ret) { return ret; } if (addr) { sev_common->reset_cs = addr & 0xffff0000; sev_common->reset_ip = addr & 0x0000ffff; sev_common->reset_data_valid = true; CPU_FOREACH(cpu) { sev_es_set_reset_vector(cpu); } } return 0; } static const QemuUUID sev_hash_table_header_guid = { .data = UUID_LE(0x9438d606, 0x4f22, 0x4cc9, 0xb4, 0x79, 0xa7, 0x93, 0xd4, 0x11, 0xfd, 0x21) }; static const QemuUUID sev_kernel_entry_guid = { .data = UUID_LE(0x4de79437, 0xabd2, 0x427f, 0xb8, 0x35, 0xd5, 0xb1, 0x72, 0xd2, 0x04, 0x5b) }; static const QemuUUID sev_initrd_entry_guid = { .data = UUID_LE(0x44baf731, 0x3a2f, 0x4bd7, 0x9a, 0xf1, 0x41, 0xe2, 0x91, 0x69, 0x78, 0x1d) }; static const QemuUUID sev_cmdline_entry_guid = { .data = UUID_LE(0x97d02dd8, 0xbd20, 0x4c94, 0xaa, 0x78, 0xe7, 0x71, 0x4d, 0x36, 0xab, 0x2a) }; static bool build_kernel_loader_hashes(PaddedSevHashTable *padded_ht, SevKernelLoaderContext *ctx, Error **errp) { SevHashTable *ht; uint8_t cmdline_hash[HASH_SIZE]; uint8_t initrd_hash[HASH_SIZE]; uint8_t kernel_hash[HASH_SIZE]; uint8_t *hashp; size_t hash_len = HASH_SIZE; /* * Calculate hash of kernel command-line with the terminating null byte. If * the user doesn't supply a command-line via -append, the 1-byte "\0" will * be used. */ hashp = cmdline_hash; if (qcrypto_hash_bytes(QCRYPTO_HASH_ALG_SHA256, ctx->cmdline_data, ctx->cmdline_size, &hashp, &hash_len, errp) < 0) { return false; } assert(hash_len == HASH_SIZE); /* * Calculate hash of initrd. If the user doesn't supply an initrd via * -initrd, an empty buffer will be used (ctx->initrd_size == 0). */ hashp = initrd_hash; if (qcrypto_hash_bytes(QCRYPTO_HASH_ALG_SHA256, ctx->initrd_data, ctx->initrd_size, &hashp, &hash_len, errp) < 0) { return false; } assert(hash_len == HASH_SIZE); /* Calculate hash of the kernel */ hashp = kernel_hash; struct iovec iov[2] = { { .iov_base = ctx->setup_data, .iov_len = ctx->setup_size }, { .iov_base = ctx->kernel_data, .iov_len = ctx->kernel_size } }; if (qcrypto_hash_bytesv(QCRYPTO_HASH_ALG_SHA256, iov, ARRAY_SIZE(iov), &hashp, &hash_len, errp) < 0) { return false; } assert(hash_len == HASH_SIZE); ht = &padded_ht->ht; ht->guid = sev_hash_table_header_guid; ht->len = sizeof(*ht); ht->cmdline.guid = sev_cmdline_entry_guid; ht->cmdline.len = sizeof(ht->cmdline); memcpy(ht->cmdline.hash, cmdline_hash, sizeof(ht->cmdline.hash)); ht->initrd.guid = sev_initrd_entry_guid; ht->initrd.len = sizeof(ht->initrd); memcpy(ht->initrd.hash, initrd_hash, sizeof(ht->initrd.hash)); ht->kernel.guid = sev_kernel_entry_guid; ht->kernel.len = sizeof(ht->kernel); memcpy(ht->kernel.hash, kernel_hash, sizeof(ht->kernel.hash)); /* zero the excess data so the measurement can be reliably calculated */ memset(padded_ht->padding, 0, sizeof(padded_ht->padding)); return true; } 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) { PaddedSevHashTable *padded_ht; hwaddr mapped_len = sizeof(*padded_ht); MemTxAttrs attrs = { 0 }; bool ret = true; /* * Populate the hashes table in the guest's memory at the OVMF-designated * area for the SEV hashes table */ padded_ht = address_space_map(&address_space_memory, area->base, &mapped_len, true, attrs); if (!padded_ht || mapped_len != sizeof(*padded_ht)) { error_setg(errp, "SEV: cannot map hashes table guest memory area"); return false; } if (build_kernel_loader_hashes(padded_ht, ctx, errp)) { if (sev_encrypt_flash(area->base, (uint8_t *)padded_ht, sizeof(*padded_ht), errp) < 0) { ret = false; } } else { ret = false; } address_space_unmap(&address_space_memory, padded_ht, mapped_len, true, mapped_len); 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) { return g_strdup(SEV_COMMON(obj)->sev_device); } static void sev_common_set_sev_device(Object *obj, const char *value, Error **errp) { SEV_COMMON(obj)->sev_device = g_strdup(value); } static bool sev_common_get_kernel_hashes(Object *obj, Error **errp) { return SEV_COMMON(obj)->kernel_hashes; } static void sev_common_set_kernel_hashes(Object *obj, bool value, Error **errp) { SEV_COMMON(obj)->kernel_hashes = value; } static void sev_common_class_init(ObjectClass *oc, void *data) { ConfidentialGuestSupportClass *klass = CONFIDENTIAL_GUEST_SUPPORT_CLASS(oc); klass->kvm_init = sev_common_kvm_init; object_class_property_add_str(oc, "sev-device", sev_common_get_sev_device, sev_common_set_sev_device); object_class_property_set_description(oc, "sev-device", "SEV device to use"); object_class_property_add_bool(oc, "kernel-hashes", sev_common_get_kernel_hashes, sev_common_set_kernel_hashes); object_class_property_set_description(oc, "kernel-hashes", "add kernel hashes to guest firmware for measured Linux boot"); } static void sev_common_instance_init(Object *obj) { SevCommonState *sev_common = SEV_COMMON(obj); sev_common->kvm_type = -1; sev_common->sev_device = g_strdup(DEFAULT_SEV_DEVICE); object_property_add_uint32_ptr(obj, "cbitpos", &sev_common->cbitpos, OBJ_PROP_FLAG_READWRITE); object_property_add_uint32_ptr(obj, "reduced-phys-bits", &sev_common->reduced_phys_bits, OBJ_PROP_FLAG_READWRITE); } /* sev guest info common to sev/sev-es/sev-snp */ static const TypeInfo sev_common_info = { .parent = TYPE_X86_CONFIDENTIAL_GUEST, .name = TYPE_SEV_COMMON, .instance_size = sizeof(SevCommonState), .instance_init = sev_common_instance_init, .class_size = sizeof(SevCommonStateClass), .class_init = sev_common_class_init, .abstract = true, .interfaces = (InterfaceInfo[]) { { TYPE_USER_CREATABLE }, { } } }; static char * sev_guest_get_dh_cert_file(Object *obj, Error **errp) { return g_strdup(SEV_GUEST(obj)->dh_cert_file); } static void sev_guest_set_dh_cert_file(Object *obj, const char *value, Error **errp) { SEV_GUEST(obj)->dh_cert_file = g_strdup(value); } static char * sev_guest_get_session_file(Object *obj, Error **errp) { SevGuestState *sev_guest = SEV_GUEST(obj); return sev_guest->session_file ? g_strdup(sev_guest->session_file) : NULL; } static void sev_guest_set_session_file(Object *obj, const char *value, Error **errp) { SEV_GUEST(obj)->session_file = g_strdup(value); } static bool sev_guest_get_legacy_vm_type(Object *obj, Error **errp) { return SEV_GUEST(obj)->legacy_vm_type; } static void sev_guest_set_legacy_vm_type(Object *obj, bool value, Error **errp) { SEV_GUEST(obj)->legacy_vm_type = value; } static void 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; klass->kvm_init = sev_kvm_init; x86_klass->kvm_type = sev_kvm_type; object_class_property_add_str(oc, "dh-cert-file", sev_guest_get_dh_cert_file, sev_guest_set_dh_cert_file); object_class_property_set_description(oc, "dh-cert-file", "guest owners DH certificate (encoded with base64)"); object_class_property_add_str(oc, "session-file", sev_guest_get_session_file, sev_guest_set_session_file); object_class_property_set_description(oc, "session-file", "guest owners session parameters (encoded with base64)"); object_class_property_add_bool(oc, "legacy-vm-type", sev_guest_get_legacy_vm_type, sev_guest_set_legacy_vm_type); object_class_property_set_description(oc, "legacy-vm-type", "use legacy VM type to maintain measurement compatibility with older QEMU or kernel versions."); } static void sev_guest_instance_init(Object *obj) { SevGuestState *sev_guest = SEV_GUEST(obj); sev_guest->policy = DEFAULT_GUEST_POLICY; object_property_add_uint32_ptr(obj, "handle", &sev_guest->handle, OBJ_PROP_FLAG_READWRITE); object_property_add_uint32_ptr(obj, "policy", &sev_guest->policy, OBJ_PROP_FLAG_READWRITE); object_apply_compat_props(obj); } /* guest info specific sev/sev-es */ static const TypeInfo sev_guest_info = { .parent = TYPE_SEV_COMMON, .name = TYPE_SEV_GUEST, .instance_size = sizeof(SevGuestState), .instance_init = sev_guest_instance_init, .class_init = sev_guest_class_init, }; static void sev_snp_guest_get_policy(Object *obj, Visitor *v, const char *name, void *opaque, Error **errp) { visit_type_uint64(v, name, (uint64_t *)&SEV_SNP_GUEST(obj)->kvm_start_conf.policy, errp); } static void sev_snp_guest_set_policy(Object *obj, Visitor *v, const char *name, void *opaque, Error **errp) { visit_type_uint64(v, name, (uint64_t *)&SEV_SNP_GUEST(obj)->kvm_start_conf.policy, errp); } static char * sev_snp_guest_get_guest_visible_workarounds(Object *obj, Error **errp) { return g_strdup(SEV_SNP_GUEST(obj)->guest_visible_workarounds); } static void sev_snp_guest_set_guest_visible_workarounds(Object *obj, const char *value, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); struct kvm_sev_snp_launch_start *start = &sev_snp_guest->kvm_start_conf; g_autofree guchar *blob; gsize len; g_free(sev_snp_guest->guest_visible_workarounds); /* store the base64 str so we don't need to re-encode in getter */ sev_snp_guest->guest_visible_workarounds = g_strdup(value); blob = qbase64_decode(sev_snp_guest->guest_visible_workarounds, -1, &len, errp); if (!blob) { return; } if (len != sizeof(start->gosvw)) { error_setg(errp, "parameter length of %lu exceeds max of %lu", len, sizeof(start->gosvw)); return; } memcpy(start->gosvw, blob, len); } static char * sev_snp_guest_get_id_block(Object *obj, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); return g_strdup(sev_snp_guest->id_block); } static void sev_snp_guest_set_id_block(Object *obj, const char *value, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); struct kvm_sev_snp_launch_finish *finish = &sev_snp_guest->kvm_finish_conf; gsize len; g_free(sev_snp_guest->id_block); g_free((guchar *)finish->id_block_uaddr); /* store the base64 str so we don't need to re-encode in getter */ sev_snp_guest->id_block = g_strdup(value); finish->id_block_uaddr = (uint64_t)qbase64_decode(sev_snp_guest->id_block, -1, &len, errp); if (!finish->id_block_uaddr) { return; } if (len != KVM_SEV_SNP_ID_BLOCK_SIZE) { error_setg(errp, "parameter length of %lu not equal to %u", len, KVM_SEV_SNP_ID_BLOCK_SIZE); return; } finish->id_block_en = (len) ? 1 : 0; } static char * sev_snp_guest_get_id_auth(Object *obj, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); return g_strdup(sev_snp_guest->id_auth); } static void sev_snp_guest_set_id_auth(Object *obj, const char *value, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); struct kvm_sev_snp_launch_finish *finish = &sev_snp_guest->kvm_finish_conf; gsize len; g_free(sev_snp_guest->id_auth); g_free((guchar *)finish->id_auth_uaddr); /* store the base64 str so we don't need to re-encode in getter */ sev_snp_guest->id_auth = g_strdup(value); finish->id_auth_uaddr = (uint64_t)qbase64_decode(sev_snp_guest->id_auth, -1, &len, errp); if (!finish->id_auth_uaddr) { return; } if (len > KVM_SEV_SNP_ID_AUTH_SIZE) { error_setg(errp, "parameter length:ID_AUTH %lu exceeds max of %u", len, KVM_SEV_SNP_ID_AUTH_SIZE); return; } } static bool sev_snp_guest_get_author_key_enabled(Object *obj, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); return !!sev_snp_guest->kvm_finish_conf.auth_key_en; } static void sev_snp_guest_set_author_key_enabled(Object *obj, bool value, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); sev_snp_guest->kvm_finish_conf.auth_key_en = value; } static bool sev_snp_guest_get_vcek_disabled(Object *obj, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); return !!sev_snp_guest->kvm_finish_conf.vcek_disabled; } static void sev_snp_guest_set_vcek_disabled(Object *obj, bool value, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); sev_snp_guest->kvm_finish_conf.vcek_disabled = value; } static char * sev_snp_guest_get_host_data(Object *obj, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); return g_strdup(sev_snp_guest->host_data); } static void sev_snp_guest_set_host_data(Object *obj, const char *value, Error **errp) { SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); struct kvm_sev_snp_launch_finish *finish = &sev_snp_guest->kvm_finish_conf; g_autofree guchar *blob; gsize len; g_free(sev_snp_guest->host_data); /* store the base64 str so we don't need to re-encode in getter */ sev_snp_guest->host_data = g_strdup(value); blob = qbase64_decode(sev_snp_guest->host_data, -1, &len, errp); if (!blob) { return; } if (len != sizeof(finish->host_data)) { error_setg(errp, "parameter length of %lu not equal to %lu", len, sizeof(finish->host_data)); return; } memcpy(finish->host_data, blob, len); } static void 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; klass->kvm_init = sev_snp_kvm_init; x86_klass->kvm_type = sev_snp_kvm_type; object_class_property_add(oc, "policy", "uint64", sev_snp_guest_get_policy, sev_snp_guest_set_policy, NULL, NULL); object_class_property_add_str(oc, "guest-visible-workarounds", sev_snp_guest_get_guest_visible_workarounds, sev_snp_guest_set_guest_visible_workarounds); object_class_property_add_str(oc, "id-block", sev_snp_guest_get_id_block, sev_snp_guest_set_id_block); object_class_property_add_str(oc, "id-auth", sev_snp_guest_get_id_auth, sev_snp_guest_set_id_auth); object_class_property_add_bool(oc, "author-key-enabled", sev_snp_guest_get_author_key_enabled, sev_snp_guest_set_author_key_enabled); object_class_property_add_bool(oc, "vcek-required", sev_snp_guest_get_vcek_disabled, sev_snp_guest_set_vcek_disabled); object_class_property_add_str(oc, "host-data", sev_snp_guest_get_host_data, sev_snp_guest_set_host_data); } static void sev_snp_guest_instance_init(Object *obj) { ConfidentialGuestSupport *cgs = CONFIDENTIAL_GUEST_SUPPORT(obj); SevSnpGuestState *sev_snp_guest = SEV_SNP_GUEST(obj); cgs->require_guest_memfd = true; /* default init/start/finish params for kvm */ sev_snp_guest->kvm_start_conf.policy = DEFAULT_SEV_SNP_POLICY; } /* guest info specific to sev-snp */ static const TypeInfo sev_snp_guest_info = { .parent = TYPE_SEV_COMMON, .name = TYPE_SEV_SNP_GUEST, .instance_size = sizeof(SevSnpGuestState), .class_init = sev_snp_guest_class_init, .instance_init = sev_snp_guest_instance_init, }; static void sev_register_types(void) { type_register_static(&sev_common_info); type_register_static(&sev_guest_info); type_register_static(&sev_snp_guest_info); } type_init(sev_register_types);