On Fri, 10 Aug 2018 17:32:23 +0200
Marc-André Lureau <marcandre.lur...@redhat.com> wrote:
> This allows to pass the last failing test from the Windows HLK TPM 2.0
> TCG PPI 1.3 tests.
>
> The interface is described in the "TCG Platform Reset Attack
> Mitigation Specification", chapter 6 "ACPI _DSM Function". According
> to Laszlo, it's not so easy to implement in OVMF, he suggested to do
> it in qemu instead.
>
> Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
> ---
> hw/tpm/tpm_ppi.h | 2 ++
> hw/i386/acpi-build.c | 46 ++++++++++++++++++++++++++++++++++++++++++++
> hw/tpm/tpm_crb.c | 1 +
> hw/tpm/tpm_ppi.c | 23 ++++++++++++++++++++++
> hw/tpm/tpm_tis.c | 1 +
> docs/specs/tpm.txt | 2 ++
> hw/tpm/trace-events | 3 +++
> 7 files changed, 78 insertions(+)
>
> diff --git a/hw/tpm/tpm_ppi.h b/hw/tpm/tpm_ppi.h
> index f6458bf87e..3239751e9f 100644
> --- a/hw/tpm/tpm_ppi.h
> +++ b/hw/tpm/tpm_ppi.h
> @@ -23,4 +23,6 @@ typedef struct TPMPPI {
> bool tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
> hwaddr addr, Object *obj, Error **errp);
>
> +void tpm_ppi_reset(TPMPPI *tpmppi);
> +
> #endif /* TPM_TPM_PPI_H */
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index c5e9a6e11d..271c7240dc 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -1824,6 +1824,13 @@ build_tpm_ppi(TPMIf *tpm, Aml *dev)
> pprq = aml_name("PPRQ");
> pprm = aml_name("PPRM");
>
> + aml_append(dev,
> + aml_operation_region("TPP3", AML_SYSTEM_MEMORY,
> + aml_int(TPM_PPI_ADDR_BASE + 0x200),
> + 0x1));
> + field = aml_field("TPP3", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE);
> + aml_append(field, aml_named_field("MOVV", 8));
> + aml_append(dev, field);
> /*
> * DerefOf in Windows is broken with SYSTEM_MEMORY. Use a dynamic
> * operation region inside of a method for getting FUNC[op].
> @@ -2166,7 +2173,46 @@ build_tpm_ppi(TPMIf *tpm, Aml *dev)
> aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
> }
> aml_append(method, ifctx);
> +
> + ifctx = aml_if(
> + aml_equal(uuid,
> + aml_touuid("376054ED-CC13-4675-901C-4756D7F2D45D")));
> + {
> + /* standard DSM query function */
> + ifctx2 = aml_if(aml_equal(function, zero));
> + {
> + uint8_t byte_list[1] = { 0x03 };
> + aml_append(ifctx2, aml_return(aml_buffer(1, byte_list)));
> + }
> + aml_append(ifctx, ifctx2);
> +
> + /*
> + * TCG Platform Reset Attack Mitigation Specification 1.0 Ch.6
> + *
> + * Arg 2 (Integer): Function Index = 1
> + * Arg 3 (Package): Arguments = Package: Type: Integer
> + * Operation Value of the Request
> + * Returns: Type: Integer
> + * 0: Success
> + * 1: General Failure
> + */
> + ifctx2 = aml_if(aml_equal(function, one));
> + {
> + aml_append(ifctx2,
> + aml_store(aml_derefof(aml_index(arguments, zero)),
> + op));
> + {
> + aml_append(ifctx2, aml_store(op, aml_name("MOVV")));
> +
> + /* 0: success */
> + aml_append(ifctx2, aml_return(zero));
> + }
> + }
> + aml_append(ifctx, ifctx2);
> + }
> + aml_append(method, ifctx);
> }
> +
> aml_append(dev, method);
> }
>
> diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
> index b243222fd6..48f6a716ad 100644
> --- a/hw/tpm/tpm_crb.c
> +++ b/hw/tpm/tpm_crb.c
> @@ -233,6 +233,7 @@ static void tpm_crb_reset(void *dev)
> {
> CRBState *s = CRB(dev);
>
> + tpm_ppi_reset(&s->ppi);
> tpm_backend_reset(s->tpmbe);
>
> memset(s->regs, 0, sizeof(s->regs));
> diff --git a/hw/tpm/tpm_ppi.c b/hw/tpm/tpm_ppi.c
> index 8b46b9dd4b..dbfe342ca2 100644
> --- a/hw/tpm/tpm_ppi.c
> +++ b/hw/tpm/tpm_ppi.c
> @@ -16,8 +16,30 @@
> #include "qapi/error.h"
> #include "cpu.h"
> #include "sysemu/memory_mapping.h"
> +#include "sysemu/reset.h"
> #include "migration/vmstate.h"
> #include "tpm_ppi.h"
> +#include "trace.h"
> +
> +void tpm_ppi_reset(TPMPPI *tpmppi)
> +{
> + char *ptr = memory_region_get_ram_ptr(&tpmppi->ram);
> +
> + if (ptr[0x200] & 0x1) {
> + GuestPhysBlockList guest_phys_blocks;
> + GuestPhysBlock *block;
> +
> + guest_phys_blocks_init(&guest_phys_blocks);
> + guest_phys_blocks_append(&guest_phys_blocks);
> + QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) {
> + trace_tpm_ppi_memset(block->host_addr,
> + block->target_end - block->target_start);
> + memset(block->host_addr, 0,
> + block->target_end - block->target_start);
> + }
> + guest_phys_blocks_free(&guest_phys_blocks);
> + }
> +}
>
> bool tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
> hwaddr addr, Object *obj, Error **errp)
> @@ -27,5 +49,6 @@ bool tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
> vmstate_register_ram(&tpmppi->ram, DEVICE(obj));
>
> memory_region_add_subregion(m, addr, &tpmppi->ram);
> +
> return true;
> }
> diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
> index 70432ffe8b..d9bfa956cc 100644
> --- a/hw/tpm/tpm_tis.c
> +++ b/hw/tpm/tpm_tis.c
> @@ -868,6 +868,7 @@ static void tpm_tis_reset(DeviceState *dev)
> s->be_buffer_size = MIN(tpm_backend_get_buffer_size(s->be_driver),
> TPM_TIS_BUFFER_MAX);
>
> + tpm_ppi_reset(&s->ppi);
> tpm_backend_reset(s->be_driver);
>
> s->active_locty = TPM_TIS_NO_LOCALITY;
> diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
> index f3b7615161..54a3e1e4c5 100644
> --- a/docs/specs/tpm.txt
> +++ b/docs/specs/tpm.txt
> @@ -121,6 +121,8 @@ layout:
> +----------+--------+--------+-------------------------------------------+
> | next_step| 0x1 | 0x159 | Operation to execute after reboot by |
> | | | | firmware. Used by firmware. |
> + +----------+--------+--------+-------------------------------------------+
> + | movv | 0x1 | 0x200 | Memory overwrite variable |
> +----------+--------+--------+-------------------------------------------+
why 0x200 and not 0x15a ?
Btw why TPM_PPI_ADDR_SIZE is 0x400 and excess bytes aren't documented anywhere?
>
> The following values are supported for the 'func' field. They correspond
> diff --git a/hw/tpm/trace-events b/hw/tpm/trace-events
> index 25bee0cecf..920d32ad55 100644
> --- a/hw/tpm/trace-events
> +++ b/hw/tpm/trace-events
> @@ -51,3 +51,6 @@ tpm_tis_mmio_write_init_abort(void) "Initiating abort"
> tpm_tis_mmio_write_lowering_irq(void) "Lowering IRQ"
> tpm_tis_mmio_write_data2send(uint32_t value, unsigned size) "Data to send to
> TPM: 0x%08x (size=%d)"
> tpm_tis_pre_save(uint8_t locty, uint32_t rw_offset) "locty: %d, rw_offset =
> %u"
> +
> +# hw/tpm/tpm_ppi.c
> +tpm_ppi_memset(uint8_t *ptr, size_t size) "memset: %p %zu"
