Generate the compute_hash_tree command
Generate the transfer command "compute_hash_tree" for incremental
updates of the non-A/B devices that enable verified boot 1.0
Other changes include:
i. factor out verity_utils to use both in build_image and blockimgdiff
ii. add a new flag 'hashtree_info_generator' in sparse_image to generate
the hashtree information.
Bug: 25170618
Test: generate a package for aosp_angler; and run simulator
Change-Id: I4d4d7a3e41dc3da810d2cbf8988e85d187c9ab0e
diff --git a/tools/releasetools/sparse_img.py b/tools/releasetools/sparse_img.py
index 083da7a..ca53ae1 100644
--- a/tools/releasetools/sparse_img.py
+++ b/tools/releasetools/sparse_img.py
@@ -33,7 +33,8 @@
"""
def __init__(self, simg_fn, file_map_fn=None, clobbered_blocks=None,
- mode="rb", build_map=True, allow_shared_blocks=False):
+ mode="rb", build_map=True, allow_shared_blocks=False,
+ hashtree_info_generator=None):
self.simg_f = f = open(simg_fn, mode)
header_bin = f.read(28)
@@ -64,6 +65,8 @@
% (total_blks, blk_sz, total_chunks))
if not build_map:
+ assert not hashtree_info_generator, \
+ "Cannot generate the hashtree info without building the offset map."
return
pos = 0 # in blocks
@@ -102,8 +105,18 @@
if data_sz != 0:
raise ValueError("Don't care chunk input size is non-zero (%u)" %
(data_sz))
- else:
- pos += chunk_sz
+ # Fills the don't care data ranges with zeros.
+ # TODO(xunchang) pass the care_map to hashtree info generator.
+ if hashtree_info_generator:
+ fill_data = '\x00' * 4
+ # In order to compute verity hashtree on device, we need to write
+ # zeros explicitly to the don't care ranges. Because these ranges may
+ # contain non-zero data from the previous build.
+ care_data.append(pos)
+ care_data.append(pos + chunk_sz)
+ offset_map.append((pos, chunk_sz, None, fill_data))
+
+ pos += chunk_sz
elif chunk_type == 0xCAC4:
raise ValueError("CRC32 chunks are not supported")
@@ -128,6 +141,10 @@
extended = extended.intersect(all_blocks).subtract(self.care_map)
self.extended = extended
+ self.hashtree_info = None
+ if hashtree_info_generator:
+ self.hashtree_info = hashtree_info_generator.Generate(self)
+
if file_map_fn:
self.LoadFileBlockMap(file_map_fn, self.clobbered_blocks,
allow_shared_blocks)
@@ -246,6 +263,8 @@
remaining = remaining.subtract(ranges)
remaining = remaining.subtract(clobbered_blocks)
+ if self.hashtree_info:
+ remaining = remaining.subtract(self.hashtree_info.hashtree_range)
# For all the remaining blocks in the care_map (ie, those that
# aren't part of the data for any file nor part of the clobbered_blocks),
@@ -308,6 +327,8 @@
out["__NONZERO-%d" % i] = rangelib.RangeSet(data=blocks)
if clobbered_blocks:
out["__COPY"] = clobbered_blocks
+ if self.hashtree_info:
+ out["__HASHTREE"] = self.hashtree_info.hashtree_range
def ResetFileMap(self):
"""Throw away the file map and treat the entire image as