libavb: Pass all vbmeta images in AvbSlotVerifyData, not just 'vbmeta'.
Right now AvbSlotVerifyData only exposes the vbmeta struct from the
'vbmeta' partition and not from any chained partition. This is
problematic as applications (bootloader, fs_mgr, etc.) may need to
access descriptors no matter where they are stored. Of course such
applications could just reimplement avb_slot_verify() themselves but
this is error-prone and unnecessary. Instead, just make
avb_slot_verify() export what is needed.
Additionally, make androidboot.vbmeta.{hash_alg, size, digest} be a
digest of all these images, not just the root.
Before this change, user-space actually had no way to properly verify
vbmeta images in non-vbmeta partitions because it lacks access to
stored_rollback_indexes[] for comparison. Now, however, user-space can
use avb_slot_verify() for verification with an AvbOps struct where
validate_vbmeta_public_key() and read_rollback_index() will pass any
image. After this, all that is needed is comparing
androidboot.vbmeta.{hash_alg, size, digest} against the value computed
over vbmeta_images[] in AvbSlotVerifyData.
Additionally, all descriptors from all vbmeta images are now easily
available which is a feature which is needed in fs_mgr to set up
non-rootfs dm-verity partitions.
Bug: 31264231
Test: New unit tests + unit tests pass.
Test: Manually tested on UEFI based bootloader.
Change-Id: I8df1de246dba0b41cb3c9a7bfc93587bb55a666c
diff --git a/Android.mk b/Android.mk
index 952572e..b474fa1 100644
--- a/Android.mk
+++ b/Android.mk
@@ -150,6 +150,7 @@
LOCAL_SRC_FILES := \
test/avb_ab_flow_unittest.cc \
test/avb_slot_verify_unittest.cc \
+ test/avb_unittest_util.cc \
test/avb_util_unittest.cc \
test/avb_vbmeta_image_unittest.cc \
test/avbtool_unittest.cc \