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 # $QEMU \ -object sev-guest,id=sev0 \ -machine ....,memory-encryption=sev0 Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx> --- accel/kvm/Makefile.objs | 2 +- accel/kvm/sev.c | 179 +++++++++++++++++++++++++++++++++++++++++ docs/amd-memory-encryption.txt | 17 ++++ include/sysemu/sev.h | 53 ++++++++++++ qemu-options.hx | 34 ++++++++ 5 files changed, 284 insertions(+), 1 deletion(-) create mode 100644 accel/kvm/sev.c create mode 100644 include/sysemu/sev.h diff --git a/accel/kvm/Makefile.objs b/accel/kvm/Makefile.objs index 85351e7de7e8..666ceef3dae3 100644 --- a/accel/kvm/Makefile.objs +++ b/accel/kvm/Makefile.objs @@ -1 +1 @@ -obj-$(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 000000000000..e93fdfeb0c8f --- /dev/null +++ b/accel/kvm/sev.c @@ -0,0 +1,179 @@ +/* + * QEMU SEV support + * + * Copyright Advanced Micro Devices 2016-2018 + * + * Author: + * Brijesh Singh <brijesh.singh@xxxxxxx> + * + * 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_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_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); +} + +/* 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 72a92b6c6353..1527f603ea2a 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=<file1>,session-file=<file2> + 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 000000000000..d2621a9d1100 --- /dev/null +++ b/include/sysemu/sev.h @@ -0,0 +1,53 @@ +/* + * QEMU Secure Encrypted Virutualization (SEV) support + * + * Copyright: Advanced Micro Devices, 2016-2018 + * + * Authors: + * Brijesh Singh <brijesh.singh@xxxxxxx> + * + * 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. + * + * # $QEMU \ + * -object sev-guest,id=sev0 \ + * -machine ...,memory-encryption=sev0 + */ +struct QSevGuestInfo { + Object parent_obj; + + char *sev_device; + uint32_t policy; + uint32_t handle; + char *dh_cert_file; + char *session_file; +}; + +struct QSevGuestInfoClass { + ObjectClass parent_class; +}; + +#endif + diff --git a/qemu-options.hx b/qemu-options.hx index bec3490d7b8d..031886c1da77 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -4280,6 +4280,40 @@ contents of @code{iv.b64} to the second secret data=$SECRET,iv=$(<iv.b64) @end example +@item -object sev-guest,id=@var{id},sev-device=@var{string}[,policy=@var{policy},handle=@var{handle},dh-cert-file=@var{file},session-file=@var{file}] + +Create a Secure Encrypted Virtualization (SEV) guest object, which can be used +to provide the guest memory encryption support on AMD processors. + +The @option{sev-device} provides the device file to use for communicating with +the SEV firmware running inside AMD Secure Processor. The default device is +'/dev/sev'. If hardware supports memory encryption then /dev/sev devices are +created by CCP driver. + +The @option{policy} provides the guest policy to be enforced by the SEV firmware +and restrict what configuration and operational commands can be performed on this +guest by the hypervisor. The policy should be provided by the guest owner and is +bound to the guest and cannot be changed throughout the lifetime of the guest. +The default is 0. + +If guest @option{policy} allows sharing the key with another SEV guest then +@option{handle} can be use to provide handle of the guest from which to share +the key. + +The @option{dh-cert-file} and @option{session-file} provides the guest owner's +Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters +are used for establishing a cryptographic session with the guest owner to +negotiate keys used for attestation. The file must be encoded in base64. + +e.g to launch a SEV guest +@example + # $QEMU \ + ...... + -object sev-guest,id=sev0 \ + -machine ...,memory-encryption=sev0 + ..... + +@end example @end table ETEXI -- 2.9.5