Re: [PATCH v3] SEV: QMP support for Inject-Launch-Secret

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Tobin Feldman-Fitzthum (tobin@linux.ibm.com) wrote:
> On 2020-09-21 15:16, Dr. David Alan Gilbert wrote:
> > * Tobin Feldman-Fitzthum (tobin@linux.vnet.ibm.com) wrote:
> > > 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 faciliates the injection of the
> > > launch secret, it cannot access the secret.
> > > 
> > > Signed-off-by: Tobin Feldman-Fitzthum <tobin@linux.vnet.ibm.com>
> > 
> > Hi Tobin,
> >   Did the ovmf stuff for agreeing the GUID for automating this ever
> > happen?
> > 
> OVMF patches have not been upstreamed yet. I think we are planning
> to do that relatively soon.

So as we're getting to the end of another qemu dev cycle; do we aim
to get this one in by itself, or to wait for the GUID?

Dave

> -Tobin
> > Dave
> > 
> > > ---
> > >  include/monitor/monitor.h |  3 ++
> > >  include/sysemu/sev.h      |  2 ++
> > >  monitor/misc.c            |  8 ++---
> > >  qapi/misc-target.json     | 18 +++++++++++
> > >  target/i386/monitor.c     |  9 ++++++
> > >  target/i386/sev-stub.c    |  5 +++
> > >  target/i386/sev.c         | 66
> > > +++++++++++++++++++++++++++++++++++++++
> > >  target/i386/trace-events  |  1 +
> > >  8 files changed, 108 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
> > > index 1018d754a6..bf049c5b00 100644
> > > --- a/include/monitor/monitor.h
> > > +++ b/include/monitor/monitor.h
> > > @@ -4,6 +4,7 @@
> > >  #include "block/block.h"
> > >  #include "qapi/qapi-types-misc.h"
> > >  #include "qemu/readline.h"
> > > +#include "include/exec/hwaddr.h"
> > > 
> > >  extern __thread Monitor *cur_mon;
> > >  typedef struct MonitorHMP MonitorHMP;
> > > @@ -36,6 +37,8 @@ void monitor_flush(Monitor *mon);
> > >  int monitor_set_cpu(int cpu_index);
> > >  int monitor_get_cpu_index(void);
> > > 
> > > +void *gpa2hva(MemoryRegion **p_mr, hwaddr addr, uint64_t size,
> > > Error **errp);
> > > +
> > >  void monitor_read_command(MonitorHMP *mon, int show_prompt);
> > >  int monitor_read_password(MonitorHMP *mon, ReadLineFunc
> > > *readline_func,
> > >                            void *opaque);
> > > diff --git a/include/sysemu/sev.h b/include/sysemu/sev.h
> > > index 98c1ec8d38..b279b293e8 100644
> > > --- a/include/sysemu/sev.h
> > > +++ b/include/sysemu/sev.h
> > > @@ -18,4 +18,6 @@
> > > 
> > >  void *sev_guest_init(const char *id);
> > >  int sev_encrypt_data(void *handle, uint8_t *ptr, uint64_t len);
> > > +int sev_inject_launch_secret(const char *hdr, const char *secret,
> > > +                             uint64_t gpa);
> > >  #endif
> > > diff --git a/monitor/misc.c b/monitor/misc.c
> > > index 89bb970b00..b9ec8ba410 100644
> > > --- a/monitor/misc.c
> > > +++ b/monitor/misc.c
> > > @@ -674,10 +674,10 @@ static void hmp_physical_memory_dump(Monitor
> > > *mon, const QDict *qdict)
> > >      memory_dump(mon, count, format, size, addr, 1);
> > >  }
> > > 
> > > -static void *gpa2hva(MemoryRegion **p_mr, hwaddr addr, Error **errp)
> > > +void *gpa2hva(MemoryRegion **p_mr, hwaddr addr, uint64_t size,
> > > Error **errp)
> > >  {
> > >      MemoryRegionSection mrs = memory_region_find(get_system_memory(),
> > > -                                                 addr, 1);
> > > +                                                 addr, size);
> > > 
> > >      if (!mrs.mr) {
> > >          error_setg(errp, "No memory is mapped at address 0x%"
> > > HWADDR_PRIx, addr);
> > > @@ -701,7 +701,7 @@ static void hmp_gpa2hva(Monitor *mon, const
> > > QDict *qdict)
> > >      MemoryRegion *mr = NULL;
> > >      void *ptr;
> > > 
> > > -    ptr = gpa2hva(&mr, addr, &local_err);
> > > +    ptr = gpa2hva(&mr, addr, 1, &local_err);
> > >      if (local_err) {
> > >          error_report_err(local_err);
> > >          return;
> > > @@ -777,7 +777,7 @@ static void hmp_gpa2hpa(Monitor *mon, const
> > > QDict *qdict)
> > >      void *ptr;
> > >      uint64_t physaddr;
> > > 
> > > -    ptr = gpa2hva(&mr, addr, &local_err);
> > > +    ptr = gpa2hva(&mr, addr, 1, &local_err);
> > >      if (local_err) {
> > >          error_report_err(local_err);
> > >          return;
> > > diff --git a/qapi/misc-target.json b/qapi/misc-target.json
> > > index dee3b45930..d145f916b3 100644
> > > --- a/qapi/misc-target.json
> > > +++ b/qapi/misc-target.json
> > > @@ -200,6 +200,24 @@
> > >  { 'command': 'query-sev-capabilities', 'returns': 'SevCapability',
> > >    'if': 'defined(TARGET_I386)' }
> > > 
> > > +##
> > > +# @sev-inject-launch-secret:
> > > +#
> > > +# This command injects a secret blob into memory of SEV guest.
> > > +#
> > > +# @packet-header: the launch secret packet header encoded in base64
> > > +#
> > > +# @secret: the launch secret data to be injected encoded in base64
> > > +#
> > > +# @gpa: the guest physical address where secret will be injected.
> > > +#
> > > +# Since: 5.1
> > > +#
> > > +##
> > > +{ 'command': 'sev-inject-launch-secret',
> > > +  'data': { 'packet-header': 'str', 'secret': 'str', 'gpa':
> > > 'uint64' },
> > > +  'if': 'defined(TARGET_I386)' }
> > > +
> > >  ##
> > >  # @dump-skeys:
> > >  #
> > > diff --git a/target/i386/monitor.c b/target/i386/monitor.c
> > > index 27ebfa3ad2..42bcfe6dc0 100644
> > > --- a/target/i386/monitor.c
> > > +++ b/target/i386/monitor.c
> > > @@ -736,3 +736,12 @@ SevCapability *qmp_query_sev_capabilities(Error
> > > **errp)
> > > 
> > >      return data;
> > >  }
> > > +
> > > +void qmp_sev_inject_launch_secret(const char *packet_hdr,
> > > +                                  const char *secret, uint64_t gpa,
> > > +                                  Error **errp)
> > > +{
> > > +    if (sev_inject_launch_secret(packet_hdr, secret, gpa) != 0) {
> > > +        error_setg(errp, "SEV inject secret failed");
> > > +    }
> > > +}
> > > diff --git a/target/i386/sev-stub.c b/target/i386/sev-stub.c
> > > index e5ee13309c..fed4588185 100644
> > > --- a/target/i386/sev-stub.c
> > > +++ b/target/i386/sev-stub.c
> > > @@ -48,3 +48,8 @@ SevCapability *sev_get_capabilities(void)
> > >  {
> > >      return NULL;
> > >  }
> > > +int sev_inject_launch_secret(const char *hdr, const char *secret,
> > > +                             uint64_t gpa)
> > > +{
> > > +    return 1;
> > > +}
> > > diff --git a/target/i386/sev.c b/target/i386/sev.c
> > > index d273174ad3..cbeb8f2e02 100644
> > > --- a/target/i386/sev.c
> > > +++ b/target/i386/sev.c
> > > @@ -28,6 +28,8 @@
> > >  #include "sysemu/runstate.h"
> > >  #include "trace.h"
> > >  #include "migration/blocker.h"
> > > +#include "exec/address-spaces.h"
> > > +#include "monitor/monitor.h"
> > > 
> > >  #define TYPE_SEV_GUEST "sev-guest"
> > >  #define SEV_GUEST(obj)                                          \
> > > @@ -769,6 +771,70 @@ 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)
> > > +{
> > > +    struct kvm_sev_launch_secret input;
> > > +    guchar *data = NULL, *hdr = NULL;
> > > +    int error, ret = 1;
> > > +    void *hva;
> > > +    gsize hdr_sz = 0, data_sz = 0;
> > > +    Error *local_err = NULL;
> > > +    MemoryRegion *mr = NULL;
> > > +
> > > +    /* secret can be inject only in this state */
> > > +    if (!sev_check_state(sev_guest, SEV_STATE_LAUNCH_SECRET)) {
> > > +        error_report("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_report("SEV: Failed to decode sequence header");
> > > +        return 1;
> > > +    }
> > > +
> > > +    data = g_base64_decode(secret, &data_sz);
> > > +    if (!data || !data_sz) {
> > > +        error_report("SEV: Failed to decode data");
> > > +        goto err;
> > > +    }
> > > +
> > > +    hva = gpa2hva(&mr, gpa, data_sz, &local_err);
> > > +    if (!hva) {
> > > +        error_report("SEV: Failed to calculate guest address.");
> > > +        goto err;
> > > +    }
> > > +
> > > +    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_report("SEV: failed to inject secret ret=%d
> > > fw_error=%d '%s'",
> > > +                     ret, error, fw_error_to_str(error));
> > > +        goto err;
> > > +    }
> > > +
> > > +    ret = 0;
> > > +
> > > +err:
> > > +    g_free(data);
> > > +    g_free(hdr);
> > > +    return ret;
> > > +}
> > > +
> > >  static void
> > >  sev_register_types(void)
> > >  {
> > > diff --git a/target/i386/trace-events b/target/i386/trace-events
> > > index 789c700d4a..9f299e94a2 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"
> > > --
> > > 2.20.1 (Apple Git-117)
> > > 
> 
-- 
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK