def ComputeAllPropertyFiles(input_file, needed_property_files):
# Write the current metadata entry with placeholders.
with zipfile.ZipFile(input_file, allowZip64=True) as input_zip:
for property_files in needed_property_files:
metadata.property_files[
property_files.name] = property_files.Compute(input_zip)
namelist = input_zip.namelist()
if METADATA_NAME in namelist or METADATA_PROTO_NAME in namelist:
ZipDelete(input_file, [METADATA_NAME, METADATA_PROTO_NAME])
output_zip = zipfile.ZipFile(input_file, 'a', allowZip64=True)
WriteMetadata(metadata, output_zip)
ZipClose(output_zip)
if OPTIONS.no_signing:
return input_file
prelim_signing = MakeTempFile(suffix='.zip')
SignOutput(input_file, prelim_signing)
return prelim_signing
def FinalizeMetadata(metadata, input_file, output_file, needed_property_files):
"""Finalizes the metadata and signs an A/B OTA package.
In order to stream an A/B OTA package, we need 'ota-streaming-property-files'
that contains the offsets and sizes for the ZIP entries. An example
property-files string is as follows.
"payload.bin:679:343,payload_properties.txt:378:45,metadata:69:379"
OTA server can pass down this string, in addition to the package URL, to the
system update client. System update client can then fetch individual ZIP
entries (ZIP_STORED) directly at the given offset of the URL.
Args:
metadata: The metadata dict for the package.
input_file: The input ZIP filename that doesn't contain the package METADATA
entry yet.
output_file: The final output ZIP filename.
needed_property_files: The list of PropertyFiles' to be generated.
"""
def ComputeAllPropertyFiles(input_file, needed_property_files):
# Write the current metadata entry with placeholders.
with zipfile.ZipFile(input_file, allowZip64=True) as input_zip:
for property_files in needed_property_files:
metadata.property_files[
property_files.name] = property_files.Compute(input_zip)
namelist = input_zip.namelist()
if METADATA_NAME in namelist or METADATA_PROTO_NAME in namelist:
ZipDelete(input_file, [METADATA_NAME, METADATA_PROTO_NAME])
output_zip = zipfile.ZipFile(input_file, 'a', allowZip64=True)
WriteMetadata(metadata, output_zip)
ZipClose(output_zip)
if OPTIONS.no_signing:
return input_file
prelim_signing = MakeTempFile(suffix='.zip')
SignOutput(input_file, prelim_signing)
return prelim_signing
def FinalizeAllPropertyFiles(prelim_signing, needed_property_files):
with zipfile.ZipFile(prelim_signing,
allowZip64=True) as prelim_signing_zip:
for property_files in needed_property_files:
metadata.property_files[
property_files.name] = property_files.Finalize(
prelim_signing_zip,
len(metadata.property_files[property_files.name]))
# SignOutput(), which in turn calls signapk.jar, will possibly reorder the ZIP
# entries, as well as padding the entry headers. We do a preliminary signing
# (with an incomplete metadata entry) to allow that to happen. Then compute
# the ZIP entry offsets, write back the final metadata and do the final
# signing.
prelim_signing = ComputeAllPropertyFiles(input_file, needed_property_files)
try:
FinalizeAllPropertyFiles(prelim_signing, needed_property_files)
except PropertyFiles.InsufficientSpaceException:
# Even with the preliminary signing, the entry orders may change
# dramatically, which leads to insufficiently reserved space during the
# first call to ComputeAllPropertyFiles(). In that case, we redo all the
# preliminary signing works, based on the already ordered ZIP entries, to
# address the issue.
prelim_signing = ComputeAllPropertyFiles(prelim_signing,
needed_property_files)
FinalizeAllPropertyFiles(prelim_signing, needed_property_files)
# Replace the METADATA entry.
ZipDelete(prelim_signing, [METADATA_NAME, METADATA_PROTO_NAME])
output_zip = zipfile.ZipFile(prelim_signing, 'a', allowZip64=True)
WriteMetadata(metadata, output_zip)
ZipClose(output_zip)
# Re-sign the package after updating the metadata entry.
if OPTIONS.no_signing:
output_file = prelim_signing
else:
SignOutput(prelim_signing, output_file)
# Reopen the final signed zip to double check the streaming metadata.
with zipfile.ZipFile(output_file, allowZip64=True) as output_zip:
for property_files in needed_property_files:
property_files.Verify(
output_zip,
metadata.property_files[property_files.name].strip())
# If requested, dump the metadata to a separate file.
output_metadata_path = OPTIONS.output_metadata_path
if output_metadata_path:
WriteMetadata(metadata, output_metadata_path)
