@@ -740,6 +740,13 @@ SevLaunchMeasureInfo *qmp_query_sev_launch_measure(Error **errp)
SevCapability *qmp_query_sev_capabilities(Error **errp)
{
- error_setg(errp, "SEV feature is not available");
- return NULL;
+ SevCapability *data;
+
+ data = sev_get_capabilities();
+ if (!data) {
+ error_setg(errp, "SEV feature is not available");
+ return NULL;
+ }
+
+ return data;
}
@@ -44,3 +44,8 @@ char *sev_get_launch_measurement(void)
{
return NULL;
}
+
+SevCapability *sev_get_capabilities(void)
+{
+ return NULL;
+}
@@ -422,6 +422,89 @@ sev_get_info(void)
return info;
}
+static int
+sev_get_pdh_info(int fd, guchar **pdh, size_t *pdh_len, guchar **cert_chain,
+ size_t *cert_chain_len)
+{
+ guchar *pdh_data, *cert_chain_data;
+ struct sev_user_data_pdh_cert_export export = {};
+ int err, r;
+
+ /* query the certificate length */
+ r = sev_platform_ioctl(fd, SEV_PDH_CERT_EXPORT, &export, &err);
+ if (r < 0) {
+ if (err != SEV_RET_INVALID_LEN) {
+ error_report("failed to export PDH cert ret=%d fw_err=%d (%s)",
+ r, err, fw_error_to_str(err));
+ return 1;
+ }
+ }
+
+ pdh_data = g_new(guchar, export.pdh_cert_len);
+ cert_chain_data = g_new(guchar, export.cert_chain_len);
+ export.pdh_cert_address = (unsigned long)pdh_data;
+ export.cert_chain_address = (unsigned long)cert_chain_data;
+
+ r = sev_platform_ioctl(fd, SEV_PDH_CERT_EXPORT, &export, &err);
+ if (r < 0) {
+ error_report("failed to export PDH cert ret=%d fw_err=%d (%s)",
+ r, err, fw_error_to_str(err));
+ goto e_free;
+ }
+
+ *pdh = pdh_data;
+ *pdh_len = export.pdh_cert_len;
+ *cert_chain = cert_chain_data;
+ *cert_chain_len = export.cert_chain_len;
+ return 0;
+
+e_free:
+ g_free(pdh_data);
+ g_free(cert_chain_data);
+ return 1;
+}
+
+SevCapability *
+sev_get_capabilities(void)
+{
+ SevCapability *cap;
+ guchar *pdh_data, *cert_chain_data;
+ size_t pdh_len = 0, cert_chain_len = 0;
+ uint32_t ebx;
+ int fd;
+
+ fd = open(DEFAULT_SEV_DEVICE, O_RDWR);
+ if (fd < 0) {
+ error_report("%s: Failed to open %s '%s'", __func__,
+ DEFAULT_SEV_DEVICE, strerror(errno));
+ return NULL;
+ }
+
+ if (sev_get_pdh_info(fd, &pdh_data, &pdh_len,
+ &cert_chain_data, &cert_chain_len)) {
+ return NULL;
+ }
+
+ cap = g_new0(SevCapability, 1);
+ cap->pdh = g_base64_encode(pdh_data, pdh_len);
+ cap->cert_chain = g_base64_encode(cert_chain_data, cert_chain_len);
+
+ host_cpuid(0x8000001F, 0, NULL, &ebx, NULL, NULL);
+ cap->cbitpos = ebx & 0x3f;
+
+ /*
+ * When SEV feature is enabled, we loose one bit in guest physical
+ * addressing.
+ */
+ cap->reduced_phys_bits = 1;
+
+ g_free(pdh_data);
+ g_free(cert_chain_data);
+
+ close(fd);
+ return cap;
+}
+
static int
sev_read_file_base64(const char *filename, guchar **data, gsize *len)
{
@@ -43,6 +43,7 @@ extern SevInfo *sev_get_info(void);
extern uint32_t sev_get_cbit_position(void);
extern uint32_t sev_get_reduced_phys_bits(void);
extern char *sev_get_launch_measurement(void);
+extern SevCapability *sev_get_capabilities(void);
typedef struct QSevGuestInfo QSevGuestInfo;
typedef struct QSevGuestInfoClass QSevGuestInfoClass;
The function can be used to get the current SEV capabilities. The capabilities include platform diffie-hellman key (pdh) and certificate chain. The key can be provided to the external entities which wants to establish a trusted channel between SEV firmware and guest owner. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> --- target/i386/monitor.c | 11 +++++-- target/i386/sev-stub.c | 5 +++ target/i386/sev.c | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++ target/i386/sev_i386.h | 1 + 4 files changed, 98 insertions(+), 2 deletions(-)