[PATCH v5 12/16] backends/confidential-guest-support: Add set_guest_policy() function

Roy Hopkins posted 16 patches 3 months, 1 week ago
There is a newer version of this series
[PATCH v5 12/16] backends/confidential-guest-support: Add set_guest_policy() function
Posted by Roy Hopkins 3 months, 1 week ago
For confidential guests a policy can be provided that defines the
security level, debug status, expected launch measurement and other
parameters that define the configuration of the confidential platform.

This commit adds a new function named set_guest_policy() that can be
implemented by each confidential platform, such as AMD SEV to set the
policy. This will allow configuration of the policy from a
multi-platform resource such as an IGVM file without the IGVM processor
requiring specific implementation details for each platform.

Signed-off-by: Roy Hopkins <roy.hopkins@suse.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
---
 backends/confidential-guest-support.c     | 12 ++++++++++++
 include/exec/confidential-guest-support.h | 21 +++++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/backends/confidential-guest-support.c b/backends/confidential-guest-support.c
index 68e6fd9d18..3c46b2cd6b 100644
--- a/backends/confidential-guest-support.c
+++ b/backends/confidential-guest-support.c
@@ -38,6 +38,17 @@ static int set_guest_state(hwaddr gpa, uint8_t *ptr, uint64_t len,
     return -1;
 }
 
+static int set_guest_policy(ConfidentialGuestPolicyType policy_type,
+                            uint64_t policy,
+                            void *policy_data1, uint32_t policy_data1_size,
+                            void *policy_data2, uint32_t policy_data2_size,
+                            Error **errp)
+{
+    error_setg(errp,
+               "Setting confidential guest policy is not supported for this platform");
+    return -1;
+}
+
 static int get_mem_map_entry(int index, ConfidentialGuestMemoryMapEntry *entry,
                              Error **errp)
 {
@@ -52,6 +63,7 @@ static void confidential_guest_support_class_init(ObjectClass *oc, void *data)
     ConfidentialGuestSupportClass *cgsc = CONFIDENTIAL_GUEST_SUPPORT_CLASS(oc);
     cgsc->check_support = check_support;
     cgsc->set_guest_state = set_guest_state;
+    cgsc->set_guest_policy = set_guest_policy;
     cgsc->get_mem_map_entry = get_mem_map_entry;
 }
 
diff --git a/include/exec/confidential-guest-support.h b/include/exec/confidential-guest-support.h
index 058c7535ca..6a9ccc2454 100644
--- a/include/exec/confidential-guest-support.h
+++ b/include/exec/confidential-guest-support.h
@@ -59,6 +59,10 @@ typedef enum ConfidentialGuestPageType {
     CGS_PAGE_TYPE_REQUIRED_MEMORY,
 } ConfidentialGuestPageType;
 
+typedef enum ConfidentialGuestPolicyType {
+    GUEST_POLICY_SEV,
+} ConfidentialGuestPolicyType;
+
 struct ConfidentialGuestSupport {
     Object parent;
 
@@ -123,6 +127,23 @@ typedef struct ConfidentialGuestSupportClass {
                            ConfidentialGuestPageType memory_type,
                            uint16_t cpu_index, Error **errp);
 
+    /*
+     * Set the guest policy. The policy can be used to configure the
+     * confidential platform, such as if debug is enabled or not and can contain
+     * information about expected launch measurements, signed verification of
+     * guest configuration and other platform data.
+     *
+     * The format of the policy data is specific to each platform. For example,
+     * SEV-SNP uses a policy bitfield in the 'policy' argument and provides an
+     * ID block and ID authentication in the 'policy_data' parameters. The type
+     * of policy data is identified by the 'policy_type' argument.
+     */
+    int (*set_guest_policy)(ConfidentialGuestPolicyType policy_type,
+                            uint64_t policy,
+                            void *policy_data1, uint32_t policy_data1_size,
+                            void *policy_data2, uint32_t policy_data2_size,
+                            Error **errp);
+
     /*
      * Iterate the system memory map, getting the entry with the given index
      * that can be populated into guest memory.
-- 
2.43.0


Re: [PATCH v5 12/16] backends/confidential-guest-support: Add set_guest_policy() function
Posted by Stefano Garzarella 2 months, 3 weeks ago
On Tue, Aug 13, 2024 at 04:01:14PM GMT, Roy Hopkins wrote:
>For confidential guests a policy can be provided that defines the
>security level, debug status, expected launch measurement and other
>parameters that define the configuration of the confidential platform.
>
>This commit adds a new function named set_guest_policy() that can be
>implemented by each confidential platform, such as AMD SEV to set the
>policy. This will allow configuration of the policy from a
>multi-platform resource such as an IGVM file without the IGVM processor
>requiring specific implementation details for each platform.
>
>Signed-off-by: Roy Hopkins <roy.hopkins@suse.com>
>Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
>Acked-by: Michael S. Tsirkin <mst@redhat.com>
>---
> backends/confidential-guest-support.c     | 12 ++++++++++++
> include/exec/confidential-guest-support.h | 21 +++++++++++++++++++++
> 2 files changed, 33 insertions(+)

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>

>
>diff --git a/backends/confidential-guest-support.c b/backends/confidential-guest-support.c
>index 68e6fd9d18..3c46b2cd6b 100644
>--- a/backends/confidential-guest-support.c
>+++ b/backends/confidential-guest-support.c
>@@ -38,6 +38,17 @@ static int set_guest_state(hwaddr gpa, uint8_t *ptr, uint64_t len,
>     return -1;
> }
>
>+static int set_guest_policy(ConfidentialGuestPolicyType policy_type,
>+                            uint64_t policy,
>+                            void *policy_data1, uint32_t policy_data1_size,
>+                            void *policy_data2, uint32_t policy_data2_size,
>+                            Error **errp)
>+{
>+    error_setg(errp,
>+               "Setting confidential guest policy is not supported for this platform");
>+    return -1;
>+}
>+
> static int get_mem_map_entry(int index, ConfidentialGuestMemoryMapEntry *entry,
>                              Error **errp)
> {
>@@ -52,6 +63,7 @@ static void confidential_guest_support_class_init(ObjectClass *oc, void *data)
>     ConfidentialGuestSupportClass *cgsc = CONFIDENTIAL_GUEST_SUPPORT_CLASS(oc);
>     cgsc->check_support = check_support;
>     cgsc->set_guest_state = set_guest_state;
>+    cgsc->set_guest_policy = set_guest_policy;
>     cgsc->get_mem_map_entry = get_mem_map_entry;
> }
>
>diff --git a/include/exec/confidential-guest-support.h b/include/exec/confidential-guest-support.h
>index 058c7535ca..6a9ccc2454 100644
>--- a/include/exec/confidential-guest-support.h
>+++ b/include/exec/confidential-guest-support.h
>@@ -59,6 +59,10 @@ typedef enum ConfidentialGuestPageType {
>     CGS_PAGE_TYPE_REQUIRED_MEMORY,
> } ConfidentialGuestPageType;
>
>+typedef enum ConfidentialGuestPolicyType {
>+    GUEST_POLICY_SEV,
>+} ConfidentialGuestPolicyType;
>+
> struct ConfidentialGuestSupport {
>     Object parent;
>
>@@ -123,6 +127,23 @@ typedef struct ConfidentialGuestSupportClass {
>                            ConfidentialGuestPageType memory_type,
>                            uint16_t cpu_index, Error **errp);
>
>+    /*
>+     * Set the guest policy. The policy can be used to configure the
>+     * confidential platform, such as if debug is enabled or not and can contain
>+     * information about expected launch measurements, signed verification of
>+     * guest configuration and other platform data.
>+     *
>+     * The format of the policy data is specific to each platform. For example,
>+     * SEV-SNP uses a policy bitfield in the 'policy' argument and provides an
>+     * ID block and ID authentication in the 'policy_data' parameters. The type
>+     * of policy data is identified by the 'policy_type' argument.
>+     */
>+    int (*set_guest_policy)(ConfidentialGuestPolicyType policy_type,
>+                            uint64_t policy,
>+                            void *policy_data1, uint32_t policy_data1_size,
>+                            void *policy_data2, uint32_t policy_data2_size,
>+                            Error **errp);
>+
>     /*
>      * Iterate the system memory map, getting the entry with the given index
>      * that can be populated into guest memory.
>-- 
>2.43.0
>