File 0061-sev-i386-add-support-to-LAUNCH_MEAS.patch of Package qemu.8001

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File 0061-sev-i386-add-support-to-LAUNCH_MEAS.patch of Package qemu.8001

From bac227caee77818baa23caab54755eece8d6890a Mon Sep 17 00:00:00 2001
From: Brijesh Singh <brijesh.singh@amd.com>
Date: Wed, 28 Feb 2018 14:36:00 -0700
Subject: [PATCH] sev/i386: add support to LAUNCH_MEASURE command

During machine creation we encrypted the guest bios image, the
LAUNCH_MEASURE command can be used to retrieve the measurement of
the encrypted memory region. This measurement is a signature of
the memory contents that can be sent to the guest owner as an
attestation that the memory was encrypted correctly by the firmware.
VM management tools like libvirt can query the measurement using
query-sev-launch-measure QMP command.

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>
[BR: FATE#322124]
Signed-off-by: Bruce Rogers <brogers@suse.com>
---
 target/i386/sev-stub.c   |  5 ++++
 target/i386/sev.c        | 63 ++++++++++++++++++++++++++++++++++++++++
 target/i386/sev_i386.h   |  2 ++
 target/i386/trace-events |  1 +
 4 files changed, 71 insertions(+)

diff --git a/target/i386/sev-stub.c b/target/i386/sev-stub.c
index c86d8c1392..2f61c32ec9 100644
--- a/target/i386/sev-stub.c
+++ b/target/i386/sev-stub.c
@@ -39,3 +39,8 @@ uint32_t sev_get_reduced_phys_bits(void)
 {
     return 0;
 }
+
+char *sev_get_launch_measurement(void)
+{
+    return NULL;
+}
diff --git a/target/i386/sev.c b/target/i386/sev.c
index dcbda4243e..a686f16a8f 100644
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -510,6 +510,68 @@ sev_launch_update_data(uint8_t *addr, uint64_t len)
     return ret;
 }
 
+static void
+sev_launch_get_measure(Notifier *notifier, void *unused)
+{
+    int ret, error;
+    guchar *data;
+    SEVState *s = sev_state;
+    struct kvm_sev_launch_measure *measurement;
+
+    if (!sev_check_state(SEV_STATE_LAUNCH_UPDATE)) {
+        return;
+    }
+
+    measurement = g_new0(struct kvm_sev_launch_measure, 1);
+
+    /* query the measurement blob length */
+    ret = sev_ioctl(sev_state->sev_fd, KVM_SEV_LAUNCH_MEASURE,
+                    measurement, &error);
+    if (!measurement->len) {
+        error_report("%s: LAUNCH_MEASURE ret=%d fw_error=%d '%s'",
+                     __func__, ret, error, fw_error_to_str(errno));
+        goto free_measurement;
+    }
+
+    data = g_new0(guchar, measurement->len);
+    measurement->uaddr = (unsigned long)data;
+
+    /* get the measurement blob */
+    ret = sev_ioctl(sev_state->sev_fd, KVM_SEV_LAUNCH_MEASURE,
+                    measurement, &error);
+    if (ret) {
+        error_report("%s: LAUNCH_MEASURE ret=%d fw_error=%d '%s'",
+                     __func__, ret, error, fw_error_to_str(errno));
+        goto free_data;
+    }
+
+    sev_set_guest_state(SEV_STATE_LAUNCH_SECRET);
+
+    /* encode the measurement value and emit the event */
+    s->measurement = g_base64_encode(data, measurement->len);
+    trace_kvm_sev_launch_measurement(s->measurement);
+
+free_data:
+    g_free(data);
+free_measurement:
+    g_free(measurement);
+}
+
+char *
+sev_get_launch_measurement(void)
+{
+    if (sev_state &&
+        sev_state->state >= SEV_STATE_LAUNCH_SECRET) {
+        return g_strdup(sev_state->measurement);
+    }
+
+    return NULL;
+}
+
+static Notifier sev_machine_done_notify = {
+    .notify = sev_launch_get_measure,
+};
+
 void *
 sev_guest_init(const char *id)
 {
@@ -590,6 +652,7 @@ sev_guest_init(const char *id)
     }
 
     ram_block_notifier_add(&sev_ram_notifier);
+    qemu_add_machine_init_done_notifier(&sev_machine_done_notify);
 
     return s;
 err:
diff --git a/target/i386/sev_i386.h b/target/i386/sev_i386.h
index 68019d6f39..2ecca66f6e 100644
--- a/target/i386/sev_i386.h
+++ b/target/i386/sev_i386.h
@@ -42,6 +42,7 @@ extern uint64_t sev_get_me_mask(void);
 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);
 
 typedef struct QSevGuestInfo QSevGuestInfo;
 typedef struct QSevGuestInfoClass QSevGuestInfoClass;
@@ -83,6 +84,7 @@ struct SEVState {
     uint32_t handle;
     int sev_fd;
     SevState state;
+    gchar *measurement;
 };
 
 typedef struct SEVState SEVState;
diff --git a/target/i386/trace-events b/target/i386/trace-events
index c0cd8e9321..f7a1a1e6b8 100644
--- a/target/i386/trace-events
+++ b/target/i386/trace-events
@@ -13,3 +13,4 @@ kvm_memcrypt_unregister_region(void *addr, size_t len) "addr %p len 0x%lu"
 kvm_sev_change_state(const char *old, const char *new) "%s -> %s"
 kvm_sev_launch_start(int policy, void *session, void *pdh) "policy 0x%x session %p pdh %p"
 kvm_sev_launch_update_data(void *addr, uint64_t len) "addr %p len 0x%" PRIu64
+kvm_sev_launch_measurement(const char *value) "data %s"

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File 0061-sev-i386-add-support-to-LAUNCH_MEAS.patch of Package qemu.8001

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