EC software sync uses precomputed hash if available

This removes the need to load the EC code at all when the precomputed
hash matches.

BUG=chrome-os-partner:17606
BRANCH=spring
TEST=wouldn't that be nice

Change-Id: If4438b9db8b1449b8fd4d90ef3acb3bbec5e09a0
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/42567

1 files changed, 13 insertions, 0 deletions

diff --git a/firmware/stub/vboot_api_stub.c b/firmware/stub/vboot_api_stub.c
index 8521db0e..dd0d5d4b 100644
--- a/firmware/stub/vboot_api_stub.c
+++ b/firmware/stub/vboot_api_stub.c
@@ -181,6 +181,19 @@ VbError_t VbExEcGetExpectedRW(enum VbSelectFirmware_t select,
   return VBERROR_SUCCESS;
 }
 
+/**
+ * Read the SHA-256 hash of the expected contents of the EC image associated
+ * with the main firmware specified by the "select" argument.
+ */
+VbError_t VbExEcGetExpectedRWHash(enum VbSelectFirmware_t select,
+				  const uint8_t **hash, int *hash_size) {
+  static const uint8_t fake_hash[32] = {1, 2, 3, 4};
+
+  *hash = fake_hash;
+  *hash_size = sizeof(fake_hash);
+  return VBERROR_SUCCESS;
+}
+
 VbError_t VbExEcUpdateRW(const uint8_t *image, int image_size) {
   return VBERROR_SUCCESS;
 }