vboot: use vboot2 for storing kernel rollback versions

Migrate to using vboot2 shared data fields for storing
kernel rollback versions:

  kernel_version_tpm_start(1) --> kernel_version_secdata(2)
  kernel_version_tpm(1) --> kernel_version(2)
  kernel_version_lowest(1) --> [removed]

Also remove VBSD from tests which no longer need it.

BUG=b:124141368, chromium:1038260
TEST=make clean && make runtests
BRANCH=none

Change-Id: I26c2ccede5fba52e1477b625ef5fc6181f60aadf
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2053179
Tested-by: Joel Kitching <kitching@chromium.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Commit-Queue: Joel Kitching <kitching@chromium.org>

3 files changed, 14 insertions, 16 deletions

diff --git a/firmware/lib/vboot_api_kernel.c b/firmware/lib/vboot_api_kernel.c
index e2c1a6c1..72224e19 100644
--- a/firmware/lib/vboot_api_kernel.c
+++ b/firmware/lib/vboot_api_kernel.c
@@ -168,7 +168,6 @@ static int vb2_reset_nv_requests(struct vb2_context *ctx)
 vb2_error_t VbBootNormal(struct vb2_context *ctx)
 {
 	struct vb2_shared_data *sd = vb2_get_sd(ctx);
-	VbSharedDataHeader *shared = sd->vbsd;
 	uint32_t max_rollforward = vb2_nv_get(ctx,
 					      VB2_NV_KERNEL_MAX_ROLLFORWARD);
 
@@ -203,20 +202,20 @@ vb2_error_t VbBootNormal(struct vb2_context *ctx)
 	 * version to less than the version currently in the TPM.  That is,
 	 * we're limiting rollforward, not allowing rollback.
 	 */
-	if (max_rollforward < shared->kernel_version_tpm_start)
-		max_rollforward = shared->kernel_version_tpm_start;
+	if (max_rollforward < sd->kernel_version_secdata)
+		max_rollforward = sd->kernel_version_secdata;
 
-	if (shared->kernel_version_tpm > max_rollforward) {
+	if (sd->kernel_version > max_rollforward) {
 		VB2_DEBUG("Limiting TPM kernel version roll-forward "
 			  "to %#x < %#x\n",
-			  max_rollforward, shared->kernel_version_tpm);
+			  max_rollforward, sd->kernel_version);
 
-		shared->kernel_version_tpm = max_rollforward;
+		sd->kernel_version = max_rollforward;
 	}
 
-	if (shared->kernel_version_tpm > shared->kernel_version_tpm_start) {
+	if (sd->kernel_version > sd->kernel_version_secdata) {
 		vb2_secdata_kernel_set(ctx, VB2_SECDATA_KERNEL_VERSIONS,
-				       shared->kernel_version_tpm);
+				       sd->kernel_version);
 	}
 
 	return rv;
@@ -381,6 +380,8 @@ vb2_error_t VbSelectAndLoadKernel(struct vb2_context *ctx,
 	/* Translate vboot2 flags and fields into vboot1. */
 	if (sd->flags & VB2_SD_FLAG_KERNEL_SIGNED)
 		sd->vbsd->flags |= VBSD_KERNEL_KEY_VERIFIED;
+	sd->vbsd->kernel_version_tpm_start = sd->kernel_version_secdata;
+	sd->vbsd->kernel_version_tpm = sd->kernel_version;
 
 	return rv;
 }
diff --git a/firmware/lib/vboot_kernel.c b/firmware/lib/vboot_kernel.c
index 722b74de..8118599d 100644
--- a/firmware/lib/vboot_kernel.c
+++ b/firmware/lib/vboot_kernel.c
@@ -439,7 +439,6 @@ vb2_error_t LoadKernel(struct vb2_context *ctx, LoadKernelParams *params)
 {
 	struct vb2_shared_data *sd = vb2_get_sd(ctx);
 	struct vb2_workbuf wb;
-	VbSharedDataHeader *shared = sd->vbsd;
 	VbSharedDataKernelCall shcall;
 	int found_partitions = 0;
 	uint32_t lowest_version = LOWEST_TPM_VERSION;
@@ -543,7 +542,7 @@ vb2_error_t LoadKernel(struct vb2_context *ctx, LoadKernelParams *params)
 					kernel_subkey,
 					lpflags,
 					params,
-					shared->kernel_version_tpm,
+					sd->kernel_version,
 					shpart,
 					&wb);
 		VbExStreamClose(stream);
@@ -611,7 +610,7 @@ vb2_error_t LoadKernel(struct vb2_context *ctx, LoadKernelParams *params)
 		 * Otherwise, we'll check all the other headers to see if they
 		 * contain a newer key.
 		 */
-		if (shpart->combined_version == shared->kernel_version_tpm) {
+		if (shpart->combined_version == sd->kernel_version) {
 			VB2_DEBUG("Same kernel version\n");
 			break;
 		}
@@ -625,7 +624,6 @@ gpt_done:
 	if (params->partition_number > 0) {
 		VB2_DEBUG("Good partition %d\n", params->partition_number);
 		shcall.check_result = VBSD_LKC_CHECK_GOOD_PARTITION;
-		shared->kernel_version_lowest = lowest_version;
 		/*
 		 * Sanity check - only store a new TPM version if we found one.
 		 * If lowest_version is still at its initial value, we didn't
@@ -633,8 +631,8 @@ gpt_done:
 		 * didn't look.
 		 */
 		if (lowest_version != LOWEST_TPM_VERSION &&
-		    lowest_version > shared->kernel_version_tpm)
-			shared->kernel_version_tpm = lowest_version;
+		    lowest_version > sd->kernel_version)
+			sd->kernel_version = lowest_version;
 
 		/* Success! */
 		rv = VB2_SUCCESS;
diff --git a/firmware/lib20/api_kernel.c b/firmware/lib20/api_kernel.c
index 1e96f281..8b146093 100644
--- a/firmware/lib20/api_kernel.c
+++ b/firmware/lib20/api_kernel.c
@@ -72,8 +72,7 @@ vb2_error_t vb2api_kernel_phase1(struct vb2_context *ctx)
 	/* Read kernel version from secdata. */
 	sd->kernel_version_secdata =
 		vb2_secdata_kernel_get(ctx, VB2_SECDATA_KERNEL_VERSIONS);
-	sd->vbsd->kernel_version_tpm = sd->kernel_version_secdata;
-	sd->vbsd->kernel_version_tpm_start = sd->kernel_version_secdata;
+	sd->kernel_version = sd->kernel_version_secdata;
 
 	/* Find the key to use to verify the kernel keyblock */
 	if ((ctx->flags & VB2_CONTEXT_RECOVERY_MODE)) {