diff options
Diffstat (limited to 'target/i386/sev.c')
| -rw-r--r-- | target/i386/sev.c | 811 |
1 files changed, 811 insertions, 0 deletions
diff --git a/target/i386/sev.c b/target/i386/sev.c new file mode 100644 index 0000000000..019d84cef2 --- /dev/null +++ b/target/i386/sev.c @@ -0,0 +1,811 @@ +/* + * QEMU SEV support + * + * Copyright Advanced Micro Devices 2016-2018 + * + * Author: + * Brijesh Singh <brijesh.singh@amd.com> + * + * 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 <linux/kvm.h> +#include <linux/psp-sev.h> + +#include <sys/ioctl.h> + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "qom/object_interfaces.h" +#include "qemu/base64.h" +#include "sysemu/kvm.h" +#include "sev_i386.h" +#include "sysemu/sysemu.h" +#include "trace.h" +#include "migration/blocker.h" + +#define DEFAULT_GUEST_POLICY 0x1 /* disable debug */ +#define DEFAULT_SEV_DEVICE "/dev/sev" + +static SEVState *sev_state; +static Error *sev_mig_blocker; + +static const char *const sev_fw_errlist[] = { + "", + "Platform state is invalid", + "Guest state is invalid", + "Platform configuration is invalid", + "Buffer too small", + "Platform is already owned", + "Certificate is invalid", + "Policy is not allowed", + "Guest is not active", + "Invalid address", + "Bad signature", + "Bad measurement", + "Asid is already owned", + "Invalid ASID", + "WBINVD is required", + "DF_FLUSH is required", + "Guest handle is invalid", + "Invalid command", + "Guest is active", + "Hardware error", + "Hardware unsafe", + "Feature not supported", + "Invalid parameter" +}; + +#define SEV_FW_MAX_ERROR ARRAY_SIZE(sev_fw_errlist) + +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 = (__u64)(unsigned long)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(SevState state) +{ + assert(sev_state); + return sev_state->state == state ? true : false; +} + +static void +sev_set_guest_state(SevState new_state) +{ + assert(new_state < SEV_STATE__MAX); + assert(sev_state); + + trace_kvm_sev_change_state(SevState_str(sev_state->state), + SevState_str(new_state)); + sev_state->state = new_state; +} + +static void +sev_ram_block_added(RAMBlockNotifier *n, void *host, size_t size) +{ + int r; + struct kvm_enc_region range; + + range.addr = (__u64)(unsigned long)host; + range.size = size; + + trace_kvm_memcrypt_register_region(host, 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, size, strerror(errno)); + exit(1); + } +} + +static void +sev_ram_block_removed(RAMBlockNotifier *n, void *host, size_t size) +{ + int r; + struct kvm_enc_region range; + + range.addr = (__u64)(unsigned long)host; + range.size = size; + + trace_kvm_memcrypt_unregister_region(host, 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, size); + } +} + +static struct RAMBlockNotifier sev_ram_notifier = { + .ram_block_added = sev_ram_block_added, + .ram_block_removed = sev_ram_block_removed, +}; + +static void +qsev_guest_finalize(Object *obj) +{ +} + +static char * +qsev_guest_get_session_file(Object *obj, Error **errp) +{ + QSevGuestInfo *s = QSEV_GUEST_INFO(obj); + + return s->session_file ? g_strdup(s->session_file) : NULL; +} + +static void +qsev_guest_set_session_file(Object *obj, const char *value, Error **errp) +{ + QSevGuestInfo *s = QSEV_GUEST_INFO(obj); + + s->session_file = g_strdup(value); +} + +static char * +qsev_guest_get_dh_cert_file(Object *obj, Error **errp) +{ + QSevGuestInfo *s = QSEV_GUEST_INFO(obj); + + return g_strdup(s->dh_cert_file); +} + +static void +qsev_guest_set_dh_cert_file(Object *obj, const char *value, Error **errp) +{ + QSevGuestInfo *s = QSEV_GUEST_INFO(obj); + + s->dh_cert_file = g_strdup(value); +} + +static char * +qsev_guest_get_sev_device(Object *obj, Error **errp) +{ + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + + return g_strdup(sev->sev_device); +} + +static void +qsev_guest_set_sev_device(Object *obj, const char *value, Error **errp) +{ + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + + sev->sev_device = g_strdup(value); +} + +static void +qsev_guest_class_init(ObjectClass *oc, void *data) +{ + object_class_property_add_str(oc, "sev-device", + qsev_guest_get_sev_device, + qsev_guest_set_sev_device, + NULL); + object_class_property_set_description(oc, "sev-device", + "SEV device to use", NULL); + object_class_property_add_str(oc, "dh-cert-file", + qsev_guest_get_dh_cert_file, + qsev_guest_set_dh_cert_file, + NULL); + object_class_property_set_description(oc, "dh-cert-file", + "guest owners DH certificate (encoded with base64)", NULL); + object_class_property_add_str(oc, "session-file", + qsev_guest_get_session_file, + qsev_guest_set_session_file, + NULL); + object_class_property_set_description(oc, "session-file", + "guest owners session parameters (encoded with base64)", NULL); +} + +static void +qsev_guest_set_handle(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + uint32_t value; + + visit_type_uint32(v, name, &value, errp); + sev->handle = value; +} + +static void +qsev_guest_set_policy(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + uint32_t value; + + visit_type_uint32(v, name, &value, errp); + sev->policy = value; +} + +static void +qsev_guest_set_cbitpos(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + uint32_t value; + + visit_type_uint32(v, name, &value, errp); + sev->cbitpos = value; +} + +static void +qsev_guest_set_reduced_phys_bits(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + uint32_t value; + + visit_type_uint32(v, name, &value, errp); + sev->reduced_phys_bits = value; +} + +static void +qsev_guest_get_policy(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + uint32_t value; + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + + value = sev->policy; + visit_type_uint32(v, name, &value, errp); +} + +static void +qsev_guest_get_handle(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + uint32_t value; + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + + value = sev->handle; + visit_type_uint32(v, name, &value, errp); +} + +static void +qsev_guest_get_cbitpos(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + uint32_t value; + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + + value = sev->cbitpos; + visit_type_uint32(v, name, &value, errp); +} + +static void +qsev_guest_get_reduced_phys_bits(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + uint32_t value; + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + + value = sev->reduced_phys_bits; + visit_type_uint32(v, name, &value, errp); +} + +static void +qsev_guest_init(Object *obj) +{ + QSevGuestInfo *sev = QSEV_GUEST_INFO(obj); + + sev->sev_device = g_strdup(DEFAULT_SEV_DEVICE); + sev->policy = DEFAULT_GUEST_POLICY; + object_property_add(obj, "policy", "uint32", qsev_guest_get_policy, + qsev_guest_set_policy, NULL, NULL, NULL); + object_property_add(obj, "handle", "uint32", qsev_guest_get_handle, + qsev_guest_set_handle, NULL, NULL, NULL); + object_property_add(obj, "cbitpos", "uint32", qsev_guest_get_cbitpos, + qsev_guest_set_cbitpos, NULL, NULL, NULL); + object_property_add(obj, "reduced-phys-bits", "uint32", + qsev_guest_get_reduced_phys_bits, + qsev_guest_set_reduced_phys_bits, NULL, NULL, NULL); +} + +/* sev guest info */ +static const TypeInfo qsev_guest_info = { + .parent = TYPE_OBJECT, + .name = TYPE_QSEV_GUEST_INFO, + .instance_size = sizeof(QSevGuestInfo), + .instance_finalize = qsev_guest_finalize, + .class_size = sizeof(QSevGuestInfoClass), + .class_init = qsev_guest_class_init, + .instance_init = qsev_guest_init, + .interfaces = (InterfaceInfo[]) { + { TYPE_USER_CREATABLE }, + { } + } +}; + +static QSevGuestInfo * +lookup_sev_guest_info(const char *id) +{ + Object *obj; + QSevGuestInfo *info; + + obj = object_resolve_path_component(object_get_objects_root(), id); + if (!obj) { + return NULL; + } + + info = (QSevGuestInfo *) + object_dynamic_cast(obj, TYPE_QSEV_GUEST_INFO); + if (!info) { + return NULL; + } + + return info; +} + +bool +sev_enabled(void) +{ + return sev_state ? true : false; +} + +uint64_t +sev_get_me_mask(void) +{ + return sev_state ? sev_state->me_mask : ~0; +} + +uint32_t +sev_get_cbit_position(void) +{ + return sev_state ? sev_state->cbitpos : 0; +} + +uint32_t +sev_get_reduced_phys_bits(void) +{ + return sev_state ? sev_state->reduced_phys_bits : 0; +} + +SevInfo * +sev_get_info(void) +{ + SevInfo *info; + + info = g_new0(SevInfo, 1); + info->enabled = sev_state ? true : false; + + if (info->enabled) { + info->api_major = sev_state->api_major; + info->api_minor = sev_state->api_minor; + info->build_id = sev_state->build_id; + info->policy = sev_state->policy; + info->state = sev_state->state; + info->handle = sev_state->handle; + } + + return info; +} + +static int +sev_get_pdh_info(int fd, guchar **pdh, size_t *pdh_len, guchar **cert_chain, + size_t *cert_chain_len) +{ + guchar *pdh_data, *cert_chain_data; + 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_report("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_report("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; +} + +SevCapability * +sev_get_capabilities(void) +{ + SevCapability *cap; + guchar *pdh_data, *cert_chain_data; + size_t pdh_len = 0, cert_chain_len = 0; + uint32_t ebx; + int fd; + + fd = open(DEFAULT_SEV_DEVICE, O_RDWR); + if (fd < 0) { + error_report("%s: Failed to open %s '%s'", __func__, + DEFAULT_SEV_DEVICE, strerror(errno)); + return NULL; + } + + if (sev_get_pdh_info(fd, &pdh_data, &pdh_len, + &cert_chain_data, &cert_chain_len)) { + return NULL; + } + + 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); + + 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; + + g_free(pdh_data); + g_free(cert_chain_data); + + close(fd); + return cap; +} + +static int +sev_read_file_base64(const char *filename, guchar **data, gsize *len) +{ + gsize sz; + gchar *base64; + GError *error = NULL; + + if (!g_file_get_contents(filename, &base64, &sz, &error)) { + error_report("failed to read '%s' (%s)", filename, error->message); + return -1; + } + + *data = g_base64_decode(base64, len); + return 0; +} + +static int +sev_launch_start(SEVState *s) +{ + gsize sz; + int ret = 1; + int fw_error; + QSevGuestInfo *sev = s->sev_info; + struct kvm_sev_launch_start *start; + guchar *session = NULL, *dh_cert = NULL; + + start = g_new0(struct kvm_sev_launch_start, 1); + + start->handle = object_property_get_int(OBJECT(sev), "handle", + &error_abort); + start->policy = object_property_get_int(OBJECT(sev), "policy", + &error_abort); + if (sev->session_file) { + if (sev_read_file_base64(sev->session_file, &session, &sz) < 0) { + return 1; + } + start->session_uaddr = (unsigned long)session; + start->session_len = sz; + } + + if (sev->dh_cert_file) { + if (sev_read_file_base64(sev->dh_cert_file, &dh_cert, &sz) < 0) { + return 1; + } + start->dh_uaddr = (unsigned long)dh_cert; + start->dh_len = sz; + } + + trace_kvm_sev_launch_start(start->policy, session, dh_cert); + ret = sev_ioctl(s->sev_fd, KVM_SEV_LAUNCH_START, start, &fw_error); + if (ret < 0) { + error_report("%s: LAUNCH_START ret=%d fw_error=%d '%s'", + __func__, ret, fw_error, fw_error_to_str(fw_error)); + return 1; + } + + object_property_set_int(OBJECT(sev), start->handle, "handle", + &error_abort); + sev_set_guest_state(SEV_STATE_LAUNCH_UPDATE); + s->handle = start->handle; + s->policy = start->policy; + + g_free(start); + g_free(session); + g_free(dh_cert); + + return 0; +} + +static int +sev_launch_update_data(uint8_t *addr, uint64_t len) +{ + int ret, fw_error; + struct kvm_sev_launch_update_data update; + + if (!addr || !len) { + return 1; + } + + update.uaddr = (__u64)(unsigned long)addr; + update.len = len; + trace_kvm_sev_launch_update_data(addr, len); + ret = sev_ioctl(sev_state->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 void +sev_launch_get_measure(Notifier *notifier, void *unused) +{ + int ret, error; + guchar *data; + SEVState *s = sev_state; + struct kvm_sev_launch_measure *measurement; + + if (!sev_check_state(SEV_STATE_LAUNCH_UPDATE)) { + return; + } + + measurement = g_new0(struct kvm_sev_launch_measure, 1); + + /* query the measurement blob length */ + ret = sev_ioctl(sev_state->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)); + goto free_measurement; + } + + data = g_new0(guchar, measurement->len); + measurement->uaddr = (unsigned long)data; + + /* get the measurement blob */ + ret = sev_ioctl(sev_state->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)); + goto free_data; + } + + sev_set_guest_state(SEV_STATE_LAUNCH_SECRET); + + /* encode the measurement value and emit the event */ + s->measurement = g_base64_encode(data, measurement->len); + trace_kvm_sev_launch_measurement(s->measurement); + +free_data: + g_free(data); +free_measurement: + g_free(measurement); +} + +char * +sev_get_launch_measurement(void) +{ + if (sev_state && + sev_state->state >= SEV_STATE_LAUNCH_SECRET) { + return g_strdup(sev_state->measurement); + } + + return NULL; +} + +static Notifier sev_machine_done_notify = { + .notify = sev_launch_get_measure, +}; + +static void +sev_launch_finish(SEVState *s) +{ + int ret, error; + Error *local_err = NULL; + + trace_kvm_sev_launch_finish(); + ret = sev_ioctl(sev_state->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_STATE_RUNNING); + + /* add migration blocker */ + error_setg(&sev_mig_blocker, + "SEV: 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, int running, RunState state) +{ + SEVState *s = opaque; + + if (running) { + if (!sev_check_state(SEV_STATE_RUNNING)) { + sev_launch_finish(s); + } + } +} + +void * +sev_guest_init(const char *id) +{ + SEVState *s; + char *devname; + int ret, fw_error; + uint32_t ebx; + uint32_t host_cbitpos; + struct sev_user_data_status status = {}; + + s = g_new0(SEVState, 1); + s->sev_info = lookup_sev_guest_info(id); + if (!s->sev_info) { + error_report("%s: '%s' is not a valid '%s' object", + __func__, id, TYPE_QSEV_GUEST_INFO); + goto err; + } + + sev_state = s; + s->state = SEV_STATE_UNINIT; + + host_cpuid(0x8000001F, 0, NULL, &ebx, NULL, NULL); + host_cbitpos = ebx & 0x3f; + + s->cbitpos = object_property_get_int(OBJECT(s->sev_info), "cbitpos", NULL); + if (host_cbitpos != s->cbitpos) { + error_report("%s: cbitpos check failed, host '%d' requested '%d'", + __func__, host_cbitpos, s->cbitpos); + goto err; + } + + s->reduced_phys_bits = object_property_get_int(OBJECT(s->sev_info), + "reduced-phys-bits", NULL); + if (s->reduced_phys_bits < 1) { + error_report("%s: reduced_phys_bits check failed, it should be >=1," + "' requested '%d'", __func__, s->reduced_phys_bits); + goto err; + } + + s->me_mask = ~(1UL << s->cbitpos); + + devname = object_property_get_str(OBJECT(s->sev_info), "sev-device", NULL); + s->sev_fd = open(devname, O_RDWR); + if (s->sev_fd < 0) { + error_report("%s: Failed to open %s '%s'", __func__, + devname, strerror(errno)); + goto err; + } + g_free(devname); + + ret = sev_platform_ioctl(s->sev_fd, SEV_PLATFORM_STATUS, &status, + &fw_error); + if (ret) { + error_report("%s: failed to get platform status ret=%d" + "fw_error='%d: %s'", __func__, ret, fw_error, + fw_error_to_str(fw_error)); + goto err; + } + s->build_id = status.build; + s->api_major = status.api_major; + s->api_minor = status.api_minor; + + trace_kvm_sev_init(); + ret = sev_ioctl(s->sev_fd, KVM_SEV_INIT, NULL, &fw_error); + if (ret) { + error_report("%s: failed to initialize ret=%d fw_error=%d '%s'", + __func__, ret, fw_error, fw_error_to_str(fw_error)); + goto err; + } + + ret = sev_launch_start(s); + if (ret) { + error_report("%s: failed to create encryption context", __func__); + goto err; + } + + ram_block_notifier_add(&sev_ram_notifier); + qemu_add_machine_init_done_notifier(&sev_machine_done_notify); + qemu_add_vm_change_state_handler(sev_vm_state_change, s); + + return s; +err: + g_free(sev_state); + sev_state = NULL; + return NULL; +} + +int +sev_encrypt_data(void *handle, uint8_t *ptr, uint64_t len) +{ + assert(handle); + + /* if SEV is in update state then encrypt the data else do nothing */ + if (sev_check_state(SEV_STATE_LAUNCH_UPDATE)) { + return sev_launch_update_data(ptr, len); + } + + return 0; +} + +static void +sev_register_types(void) +{ + type_register_static(&qsev_guest_info); +} + +type_init(sev_register_types); |