[coreboot-gerrit] Change in ...coreboot[master]: vboot: use vboot2 API to set initial secdatak value

[Joel Kitching (Code Review)]

Hello Julius Werner, build bot (Jenkins),

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/33386

to look at the new patch set (#2).

Change subject: vboot: use vboot2 API to set initial secdatak value
......................................................................

vboot: use vboot2 API to set initial secdatak value

Previously, the initial value for secdatak was embedded
in secdata_tpm.c as a uint8_t array.  Switch to using
vb2api_secdatak_create instead, and write the value in
ctx->secdatak.

Remove an unnecessary call to vb2api_secdata_create in
_factory_initialize_tpm.

BUG=b:124141368, chromium:972956
TEST=make clean && make test-abuild
BRANCH=none

TEST=Check that size and value of initial secdatak
     has not changed.  Apply the patch below and
     check for this output:
_factory_initialize_tpm():266: _factory_initialize_tpm: secdatak sizes are identical? 1
_factory_initialize_tpm():269: _factory_initialize_tpm: secdatak values are identical? 1

diff --git a/src/security/vboot/secdata_tpm.c b/src/security/vboot/secdata_tpm.c
index ff62185107..c1818b482f 100644
--- a/src/security/vboot/secdata_tpm.c
+++ b/src/security/vboot/secdata_tpm.c
@@ -148,6 +148,18 @@ static uint32_t write_secdata(uint32_t index,
        return TPM_E_CORRUPTED_STATE;
 }

+/*
+ * This is derived from rollback_index.h of vboot_reference. see struct
+ * RollbackSpaceKernel for details.
+ */
+static const uint8_t secdata_kernel[] = {
+       0x02,
+       0x4C, 0x57, 0x52, 0x47,
+       0x00, 0x00, 0x00, 0x00,
+       0x00, 0x00, 0x00,
+       0xE8,
+};
+
 /*
  * This is used to initialize the TPM space for recovery hash after defining
  * it. Since there is no data available to calculate hash at the point where TPM
@@ -250,6 +262,11 @@ static uint32_t _factory_initialize_tpm(struct vb2_context *ctx)
         * indication that TPM factory initialization was successfully
         * completed.
         */
+       VBDEBUG("%s: secdatak sizes are identical? %d\n", __func__,
+               sizeof(secdata_kernel) == sizeof(ctx->secdatak));
+       VBDEBUG("%s: secdatak values are identical? %d\n", __func__,
+               memcmp(secdata_kernel, ctx->secdatak,
+                      sizeof(secdata_kernel)) == 0);
        RETURN_ON_FAILURE(set_kernel_space(ctx->secdatak));

if (CONFIG(VBOOT_HAS_REC_HASH_SPACE))
@@ -452,7 +469,7 @@ uint32_t antirollback_read_space_firmware(struct vb2_context *ctx)

/* Read the firmware space. */
        rv = read_space_firmware(ctx);
-       if (rv == TPM_E_BADINDEX) {
+       if (true) {
                /*
                 * This seems the first time we've run. Initialize the TPM.
                 */

Change-Id: I74261453df6cc55ef3f38d8fb922bcc604084c0a
Signed-off-by: Joel Kitching 
Cq-Depend: chromium:1652874, chromium:1655049
---
M src/security/vboot/secdata_tpm.c
1 file changed, 9 insertions(+), 21 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/86/33386/2