1 /*
2 * QEMU Confidential Guest support
3 * This interface describes the common pieces between various
4 * schemes for protecting guest memory or other state against a
5 * compromised hypervisor. This includes memory encryption (AMD's
6 * SEV and Intel's MKTME) or special protection modes (PEF on POWER,
7 * or PV on s390x).
8 *
9 * Copyright Red Hat.
10 *
11 * Authors:
12 * David Gibson <david@gibson.dropbear.id.au>
13 *
14 * This work is licensed under the terms of the GNU GPL, version 2 or
15 * later. See the COPYING file in the top-level directory.
16 *
17 */
18 #ifndef QEMU_CONFIDENTIAL_GUEST_SUPPORT_H
19 #define QEMU_CONFIDENTIAL_GUEST_SUPPORT_H
20
21 #include "qom/object.h"
22
23 #define TYPE_CONFIDENTIAL_GUEST_SUPPORT "confidential-guest-support"
24 OBJECT_DECLARE_TYPE(ConfidentialGuestSupport,
25 ConfidentialGuestSupportClass,
26 CONFIDENTIAL_GUEST_SUPPORT)
27
28
29 struct ConfidentialGuestSupport {
30 Object parent;
31
32 /*
33 * True if the machine should use guest_memfd for RAM.
34 */
35 bool require_guest_memfd;
36
37 /*
38 * ready: flag set by CGS initialization code once it's ready to
39 * start executing instructions in a potentially-secure
40 * guest
41 *
42 * The definition here is a bit fuzzy, because this is essentially
43 * part of a self-sanity-check, rather than a strict mechanism.
44 *
45 * It's not feasible to have a single point in the common machine
46 * init path to configure confidential guest support, because
47 * different mechanisms have different interdependencies requiring
48 * initialization in different places, often in arch or machine
49 * type specific code. It's also usually not possible to check
50 * for invalid configurations until that initialization code.
51 * That means it would be very easy to have a bug allowing CGS
52 * init to be bypassed entirely in certain configurations.
53 *
54 * Silently ignoring a requested security feature would be bad, so
55 * to avoid that we check late in init that this 'ready' flag is
56 * set if CGS was requested. If the CGS init hasn't happened, and
57 * so 'ready' is not set, we'll abort.
58 */
59 bool ready;
60 };
61
62 typedef struct ConfidentialGuestSupportClass {
63 ObjectClass parent;
64
65 int (*kvm_init)(ConfidentialGuestSupport *cgs, Error **errp);
66 int (*kvm_reset)(ConfidentialGuestSupport *cgs, Error **errp);
67 } ConfidentialGuestSupportClass;
68
confidential_guest_kvm_init(ConfidentialGuestSupport * cgs,Error ** errp)69 static inline int confidential_guest_kvm_init(ConfidentialGuestSupport *cgs,
70 Error **errp)
71 {
72 ConfidentialGuestSupportClass *klass;
73
74 klass = CONFIDENTIAL_GUEST_SUPPORT_GET_CLASS(cgs);
75 if (klass->kvm_init) {
76 return klass->kvm_init(cgs, errp);
77 }
78
79 return 0;
80 }
81
confidential_guest_kvm_reset(ConfidentialGuestSupport * cgs,Error ** errp)82 static inline int confidential_guest_kvm_reset(ConfidentialGuestSupport *cgs,
83 Error **errp)
84 {
85 ConfidentialGuestSupportClass *klass;
86
87 klass = CONFIDENTIAL_GUEST_SUPPORT_GET_CLASS(cgs);
88 if (klass->kvm_reset) {
89 return klass->kvm_reset(cgs, errp);
90 }
91
92 return 0;
93 }
94
95 #endif /* QEMU_CONFIDENTIAL_GUEST_SUPPORT_H */
96