sev: add sev-inject-launch-secret

AMD SEV allows a guest owner to inject a secret blob
into the memory of a virtual machine. The secret is
encrypted with the SEV Transport Encryption Key and
integrity is guaranteed with the Transport Integrity
Key. Although QEMU facilitates the injection of the
launch secret, it cannot access the secret.

Signed-off-by: Tobin Feldman-Fitzthum <tobin@linux.ibm.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Message-Id: <20201027170303.47550-1-tobin@linux.ibm.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

4 files changed, 78 insertions, 0 deletions

diff --git a/target/i386/monitor.c b/target/i386/monitor.c
index 9f9e1c4..1bc9144 100644
--- a/target/i386/monitor.c
+++ b/target/i386/monitor.c
@@ -729,3 +729,10 @@ SevCapability *qmp_query_sev_capabilities(Error **errp)
 {
     return sev_get_capabilities(errp);
 }
+
+void qmp_sev_inject_launch_secret(const char *packet_hdr,
+                                  const char *secret, uint64_t gpa,
+                                  Error **errp)
+{
+    sev_inject_launch_secret(packet_hdr, secret, gpa, errp);
+}
diff --git a/target/i386/sev-stub.c b/target/i386/sev-stub.c
index 88e3f39..c1fecc2 100644
--- a/target/i386/sev-stub.c
+++ b/target/i386/sev-stub.c
@@ -49,3 +49,8 @@ SevCapability *sev_get_capabilities(Error **errp)
     error_setg(errp, "SEV is not available in this QEMU");
     return NULL;
 }
+int sev_inject_launch_secret(const char *hdr, const char *secret,
+                             uint64_t gpa, Error **errp)
+{
+    return 1;
+}
diff --git a/target/i386/sev.c b/target/i386/sev.c
index 93c4d60..1546606 100644
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -29,6 +29,8 @@
 #include "trace.h"
 #include "migration/blocker.h"
 #include "qom/object.h"
+#include "exec/address-spaces.h"
+#include "monitor/monitor.h"
 
 #define TYPE_SEV_GUEST "sev-guest"
 OBJECT_DECLARE_SIMPLE_TYPE(SevGuestState, SEV_GUEST)
@@ -785,6 +787,69 @@ sev_encrypt_data(void *handle, uint8_t *ptr, uint64_t len)
     return 0;
 }
 
+int sev_inject_launch_secret(const char *packet_hdr, const char *secret,
+                             uint64_t gpa, Error **errp)
+{
+    struct kvm_sev_launch_secret input;
+    g_autofree guchar *data = NULL, *hdr = NULL;
+    int error, ret = 1;
+    void *hva;
+    gsize hdr_sz = 0, data_sz = 0;
+    MemoryRegion *mr = NULL;
+
+    if (!sev_guest) {
+        error_setg(errp, "SEV: SEV not enabled.");
+        return 1;
+    }
+
+    /* secret can be injected only in this state */
+    if (!sev_check_state(sev_guest, SEV_STATE_LAUNCH_SECRET)) {
+        error_setg(errp, "SEV: Not in correct state. (LSECRET) %x",
+                     sev_guest->state);
+        return 1;
+    }
+
+    hdr = g_base64_decode(packet_hdr, &hdr_sz);
+    if (!hdr || !hdr_sz) {
+        error_setg(errp, "SEV: Failed to decode sequence header");
+        return 1;
+    }
+
+    data = g_base64_decode(secret, &data_sz);
+    if (!data || !data_sz) {
+        error_setg(errp, "SEV: Failed to decode data");
+        return 1;
+    }
+
+    hva = gpa2hva(&mr, gpa, data_sz, errp);
+    if (!hva) {
+        error_prepend(errp, "SEV: Failed to calculate guest address: ");
+        return 1;
+    }
+
+    input.hdr_uaddr = (uint64_t)(unsigned long)hdr;
+    input.hdr_len = hdr_sz;
+
+    input.trans_uaddr = (uint64_t)(unsigned long)data;
+    input.trans_len = data_sz;
+
+    input.guest_uaddr = (uint64_t)(unsigned long)hva;
+    input.guest_len = data_sz;
+
+    trace_kvm_sev_launch_secret(gpa, input.guest_uaddr,
+                                input.trans_uaddr, input.trans_len);
+
+    ret = sev_ioctl(sev_guest->sev_fd, KVM_SEV_LAUNCH_SECRET,
+                    &input, &error);
+    if (ret) {
+        error_setg(errp, "SEV: failed to inject secret ret=%d fw_error=%d '%s'",
+                     ret, error, fw_error_to_str(error));
+        return ret;
+    }
+
+    return 0;
+}
+
 static void
 sev_register_types(void)
 {
diff --git a/target/i386/trace-events b/target/i386/trace-events
index 789c700..9f299e9 100644
--- a/target/i386/trace-events
+++ b/target/i386/trace-events
@@ -15,3 +15,4 @@ kvm_sev_launch_start(int policy, void *session, void *pdh) "policy 0x%x session
 kvm_sev_launch_update_data(void *addr, uint64_t len) "addr %p len 0x%" PRIu64
 kvm_sev_launch_measurement(const char *value) "data %s"
 kvm_sev_launch_finish(void) ""
+kvm_sev_launch_secret(uint64_t hpa, uint64_t hva, uint64_t secret, int len) "hpa 0x%" PRIx64 " hva 0x%" PRIx64 " data 0x%" PRIx64 " len %d"