From 725b55269e39ee0c64daf556b019d1eb70940b21 Mon Sep 17 00:00:00 2001 From: Brijesh Singh Date: Tue, 6 Feb 2018 19:08:08 -0600 Subject: [PATCH] accel: add Secure Encrypted Virtulization (SEV) object Add a new memory encryption object 'sev-guest'. The object will be used to create enrypted VMs on AMD EPYC CPU. The object provides the properties to pass guest owner's public Diffie-hellman key, guest policy and session information required to create the memory encryption context within the SEV firmware. e.g to launch SEV guest # $QEMU \ -object sev-guest,id=sev0 \ -machine ....,memory-encryption=sev0 Cc: Paolo Bonzini Signed-off-by: Brijesh Singh [BR: FATE#322124] Signed-off-by: Bruce Rogers --- accel/kvm/Makefile.objs | 2 +- accel/kvm/sev.c | 214 +++++++++++++++++++++++++++++++++++++++++ docs/amd-memory-encryption.txt | 17 ++++ include/sysemu/sev.h | 54 +++++++++++ qemu-options.hx | 36 +++++++ 5 files changed, 322 insertions(+), 1 deletion(-) create mode 100644 accel/kvm/sev.c create mode 100644 include/sysemu/sev.h diff --git a/accel/kvm/Makefile.objs b/accel/kvm/Makefile.objs index 85351e7de7..666ceef3da 100644 --- a/accel/kvm/Makefile.objs +++ b/accel/kvm/Makefile.objs @@ -1 +1 @@ -obj-$(CONFIG_KVM) += kvm-all.o +obj-$(CONFIG_KVM) += kvm-all.o sev.o diff --git a/accel/kvm/sev.c b/accel/kvm/sev.c new file mode 100644 index 0000000000..57e092a0bd --- /dev/null +++ b/accel/kvm/sev.c @@ -0,0 +1,214 @@ +/* + * 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 "qapi/error.h" +#include "qom/object_interfaces.h" +#include "qemu/base64.h" +#include "sysemu/kvm.h" +#include "sysemu/sev.h" +#include "sysemu/sysemu.h" + +#define DEFAULT_GUEST_POLICY 0x1 /* disable debug */ +#define DEFAULT_SEV_DEVICE "/dev/sev" + +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_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 uint32_t +sev_get_host_cbitpos(void) +{ + uint32_t ebx; + + host_cpuid(0x8000001F, 0, NULL, &ebx, NULL, NULL); + + return ebx & 0x3f; +} + +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; + sev->cbitpos = sev_get_host_cbitpos(); + 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); +} + +/* 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 void +sev_register_types(void) +{ + type_register_static(&qsev_guest_info); +} + +type_init(sev_register_types); diff --git a/docs/amd-memory-encryption.txt b/docs/amd-memory-encryption.txt index 72a92b6c63..1527f603ea 100644 --- a/docs/amd-memory-encryption.txt +++ b/docs/amd-memory-encryption.txt @@ -35,10 +35,21 @@ in bad measurement). The guest policy is a 4-byte data structure containing several flags that restricts what can be done on running SEV guest. See KM Spec section 3 and 6.2 for more details. +The guest policy can be provided via the 'policy' property (see below) + +# ${QEMU} \ + sev-guest,id=sev0,policy=0x1...\ + Guest owners provided DH certificate and session parameters will be used to establish a cryptographic session with the guest owner to negotiate keys used for the attestation. +The DH certificate and session blob can be provided via 'dh-cert-file' and +'session-file' property (see below + +# ${QEMU} \ + sev-guest,id=sev0,dh-cert-file=,session-file= + LAUNCH_UPDATE_DATA encrypts the memory region using the cryptographic context created via LAUNCH_START command. If required, this command can be called multiple times to encrypt different memory regions. The command also calculates @@ -59,6 +70,12 @@ context. See SEV KM API Spec [1] 'Launching a guest' usage flow (Appendix A) for the complete flow chart. +To launch a SEV guest + +# ${QEMU} \ + -machine ...,memory-encryption=sev0 \ + -object sev-guest,id=sev0 + Debugging ----------- Since memory contents of SEV guest is encrypted hence hypervisor access to the diff --git a/include/sysemu/sev.h b/include/sysemu/sev.h new file mode 100644 index 0000000000..eed679653d --- /dev/null +++ b/include/sysemu/sev.h @@ -0,0 +1,54 @@ +/* + * QEMU Secure Encrypted Virutualization (SEV) support + * + * Copyright: Advanced Micro Devices, 2016-2018 + * + * Authors: + * 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. + * + */ + +#ifndef QEMU_SEV_H +#define QEMU_SEV_H + +#include "qom/object.h" +#include "qapi/error.h" +#include "sysemu/kvm.h" +#include "qemu/error-report.h" + +#define TYPE_QSEV_GUEST_INFO "sev-guest" +#define QSEV_GUEST_INFO(obj) \ + OBJECT_CHECK(QSevGuestInfo, (obj), TYPE_QSEV_GUEST_INFO) + +typedef struct QSevGuestInfo QSevGuestInfo; +typedef struct QSevGuestInfoClass QSevGuestInfoClass; + +/** + * QSevGuestInfo: + * + * The QSevGuestInfo object is used for creating a SEV guest. + * + * # $QEMU \ + * -object sev-guest,id=sev0 \ + * -machine ...,memory-encryption=sev0 + */ +struct QSevGuestInfo { + Object parent_obj; + + char *sev_device; + uint32_t policy; + uint32_t handle; + char *dh_cert_file; + char *session_file; + uint32_t cbitpos; +}; + +struct QSevGuestInfoClass { + ObjectClass parent_class; +}; + +#endif + diff --git a/qemu-options.hx b/qemu-options.hx index 5385832707..5acf180991 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -4470,6 +4470,42 @@ contents of @code{iv.b64} to the second secret data=$SECRET,iv=$(