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>
Cc: Richard Henderson <rth@xxxxxxxxxxx>
Cc: Eduardo Habkost <ehabkost@xxxxxxxxxx>
Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
---
docs/amd-memory-encryption.txt | 17 +++
qemu-options.hx | 44 ++++++++
target/i386/Makefile.objs | 2 +-
target/i386/sev.c | 228 +++++++++++++++++++++++++++++++++++++++++
target/i386/sev_i386.h | 61 +++++++++++
5 files changed, 351 insertions(+), 1 deletion(-)
create mode 100644 target/i386/sev.c
create mode 100644 target/i386/sev_i386.h
diff --git a/docs/amd-memory-encryption.txt b/docs/amd-memory-encryption.txt
index 72a92b6c6353..8711da9ed598 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
+
+# ${QEMU} \
+ -machine ...,memory-encryption=sev0 \
+ -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5
+
Debugging
-----------
Since memory contents of SEV guest is encrypted hence hypervisor access to the
diff --git a/qemu-options.hx b/qemu-options.hx
index a6648ca073f2..f961b62bcbb2 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -4313,6 +4313,50 @@ contents of @code{iv.b64} to the second secret
data=$SECRET,iv=$(<iv.b64)
@end example
+@item -object sev-guest,id=@var{id},cbitpos=@var{cbitpos},reduced-phys-bits=@var{val},[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.
+
+When memory encryption is enabled, one of the physical address bit (aka the
+C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos}
+is used to provide the C-bit position. The C-bit position is Host family dependent
+hence user must provide this value. On EPYC, the value should be 47.
+
+When memory encryption is enabled, we loose certain bits in physical address space.
+The @option{reduced-phys-bits} is used to provide the number of bits we loose in
+physical address space. Similar to C-bit, the value is Host family dependent.
+On EPYC, the value should be 5.
+
+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
+ # $QEMU \
+ ......
+ -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \
+ -machine ...,memory-encryption=sev0
+ .....
+
+@end example
@end table
ETEXI
diff --git a/target/i386/Makefile.objs b/target/i386/Makefile.objs
index f5c6ef20a7bb..76aeaeae2750 100644
--- a/target/i386/Makefile.objs
+++ b/target/i386/Makefile.objs
@@ -4,7 +4,7 @@ obj-$(CONFIG_TCG) += bpt_helper.o cc_helper.o excp_helper.o fpu_helper.o
obj-$(CONFIG_TCG) += int_helper.o mem_helper.o misc_helper.o mpx_helper.o
obj-$(CONFIG_TCG) += seg_helper.o smm_helper.o svm_helper.o
obj-$(CONFIG_SOFTMMU) += machine.o arch_memory_mapping.o arch_dump.o monitor.o
-obj-$(CONFIG_KVM) += kvm.o hyperv.o
+obj-$(CONFIG_KVM) += kvm.o hyperv.o sev.o
obj-$(call lnot,$(CONFIG_KVM)) += kvm-stub.o
# HAX support
ifdef CONFIG_WIN32
diff --git a/target/i386/sev.c b/target/i386/sev.c
new file mode 100644
index 000000000000..ab42e4a456d2
--- /dev/null
+++ b/target/i386/sev.c
@@ -0,0 +1,228 @@
+/*
+ * 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 "sev_i386.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_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 void
+sev_register_types(void)
+{
+ type_register_static(&qsev_guest_info);
+}
+
+type_init(sev_register_types);
diff --git a/target/i386/sev_i386.h b/target/i386/sev_i386.h
new file mode 100644
index 000000000000..caf879c3b874
--- /dev/null
+++ b/target/i386/sev_i386.h
@@ -0,0 +1,61 @@
+/*
+ * 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_I386_H
+#define QEMU_SEV_I386_H
+
+#include "qom/object.h"
+#include "qapi/error.h"
+#include "sysemu/kvm.h"
+#include "qemu/error-report.h"
+
+#define SEV_POLICY_NODBG 0x1
+#define SEV_POLICY_NOKS 0x2
+#define SEV_POLICY_ES 0x4
+#define SEV_POLICY_NOSEND 0x8
+#define SEV_POLICY_DOMAIN 0x10
+#define SEV_POLICY_SEV 0x20
+
+#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;
+ uint32_t reduced_phys_bits;
+};
+
+struct QSevGuestInfoClass {
+ ObjectClass parent_class;
+};
+
+#endif
--
2.14.3
