src/security/vboot: Set up secure counter space in TPM NVRAM

High Definition (HD) protected content playback requires secure counters
that are updated at regular interval while the protected content is
playing. To support similar use-cases, define space for secure counters
in TPM NVRAM and initialize them. These counters are defined once during
the factory initialization stage. Also add
VBOOT_DEFINE_WIDEVINE_COUNTERS config item to enable these secure
counters only on the mainboard where they are required/used.

BUG=b:205261728
TEST=Build and boot to OS in guybrush. Ensure that the secure counters
are defined successfully in TPM NVRAM space.
tlcl_define_space: response is 0
tlcl_define_space: response is 0
tlcl_define_space: response is 0
tlcl_define_space: response is 0

On reboot if forced to redefine the space, it is identified as already
defined.
tlcl_define_space: response is 14c
define_space():219: define_space: Secure Counter space already exists
tlcl_define_space: response is 14c
define_space():219: define_space: Secure Counter space already exists
tlcl_define_space: response is 14c
define_space():219: define_space: Secure Counter space already exists
tlcl_define_space: response is 14c
define_space():219: define_space: Secure Counter space already exists

Change-Id: I915fbdada60e242d911b748ad5dc28028de9b657
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59476
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

1 files changed, 30 insertions, 0 deletions

diff --git a/src/security/vboot/secdata_tpm.c b/src/security/vboot/secdata_tpm.c
index 47efe2dd00..6d8e281955 100644
--- a/src/security/vboot/secdata_tpm.c
+++ b/src/security/vboot/secdata_tpm.c
@@ -158,6 +158,18 @@ static const TPMA_NV zte_rma_bytes_attr = {
 	.TPMA_NV_POLICY_DELETE = 1,
 };
 
+static const TPMA_NV rw_orderly_counter_attributes = {
+	.TPMA_NV_COUNTER = 1,
+	.TPMA_NV_ORDERLY = 1,
+	.TPMA_NV_AUTHREAD = 1,
+	.TPMA_NV_AUTHWRITE = 1,
+	.TPMA_NV_PLATFORMCREATE = 1,
+	.TPMA_NV_WRITE_STCLEAR = 1,
+	.TPMA_NV_PPREAD = 1,
+	.TPMA_NV_PPWRITE = 1,
+	.TPMA_NV_NO_DA = 1,
+};
+
 /*
  * This policy digest was obtained using TPM2_PolicyOR on 3 digests
  * corresponding to a sequence of
@@ -350,6 +362,19 @@ static uint32_t enterprise_rollback_create_counter(void)
 				 rw_counter_attributes, NULL, 0);
 }
 
+static uint32_t setup_widevine_counter_spaces(void)
+{
+	uint32_t index, rv;
+
+	for (index = 0; index < NUM_WIDEVINE_COUNTERS; index++) {
+		rv = define_space(WIDEVINE_COUNTER_NAME, WIDEVINE_COUNTER_NV_INDEX(index),
+				WIDEVINE_COUNTER_SIZE, rw_orderly_counter_attributes, NULL, 0);
+		if (rv != TPM_SUCCESS)
+			return rv;
+	}
+	return TPM_SUCCESS;
+}
+
 static uint32_t _factory_initialize_tpm(struct vb2_context *ctx)
 {
 	RETURN_ON_FAILURE(tlcl_force_clear());
@@ -391,6 +416,11 @@ static uint32_t _factory_initialize_tpm(struct vb2_context *ctx)
 	if (CONFIG(CHROMEOS))
 		RETURN_ON_FAILURE(enterprise_rollback_create_counter());
 
+	/* Define widevine counter space. No need to increment/write to the secure counters
+	   and are expected to be incremented during the first use. */
+	if (CONFIG(VBOOT_DEFINE_WIDEVINE_COUNTERS))
+		RETURN_ON_FAILURE(setup_widevine_counter_spaces());
+
 	RETURN_ON_FAILURE(setup_firmware_space(ctx));
 
 	return TPM_SUCCESS;