Revert "Revert "releasetools: Generate streamable A/B OTA packages.""
This reverts commit ea4325baf8a673e869cac8981781cf57c4821cb5 to re-land
commit ef1bb4360f0b9ccc54afd7a39077b7ca4d8a9a36. It fixes the bug when
handling a package without care_map.txt (e.g. dm-verity not enabled).
In order to support streaming A/B OTA packages, we pack
payload_properties.txt and care_map.txt in ZIP_STORED mode. These two
entries along with payload.bin (already in ZIP_STORED prior to this CL)
can be fetched directly based on the offset and length info.
We write the offset and length info into the package metadata entry
(META-INF/com/android/metadata), which can be parsed by the OTA server.
payload_properties.txt and care_map.txt are usually less than 1-KiB. So
the change only incurs marginal size increase.
Bug: 33382114
Test: Generate an A/B OTA package. Verify the 'streaming-property-files'
entry in the metadata file.
Test: Generate an A/B OTA package on a device with dm-verity not enabled.
Change-Id: I3469c8b62385a1fc58b4fb82e3f9d4690aef52ba
diff --git a/tools/releasetools/ota_from_target_files.py b/tools/releasetools/ota_from_target_files.py
index bad3f4c..7310470 100755
--- a/tools/releasetools/ota_from_target_files.py
+++ b/tools/releasetools/ota_from_target_files.py
@@ -1226,6 +1226,25 @@
source_file=None):
"""Generate an Android OTA package that has A/B update payload."""
+ def ComputeStreamingMetadata(zip_file):
+ """Compute the streaming metadata for a given zip."""
+
+ def ComputeEntryOffsetSize(name):
+ """Compute the zip entry offset and size."""
+ info = zip_file.getinfo(name)
+ offset = info.header_offset + len(info.FileHeader())
+ size = info.file_size
+ return '%s:%d:%d' % (name, offset, size)
+
+ # payload.bin and payload_properties.txt must exist.
+ offsets = [ComputeEntryOffsetSize('payload.bin'),
+ ComputeEntryOffsetSize('payload_properties.txt')]
+
+ # care_map.txt is available only if dm-verity is enabled.
+ if 'care_map.txt' in zip_file.namelist():
+ offsets.append(ComputeEntryOffsetSize('care_map.txt'))
+ return ','.join(offsets)
+
# The place where the output from the subprocess should go.
log_file = sys.stdout if OPTIONS.verbose else subprocess.PIPE
@@ -1363,11 +1382,15 @@
f.write("POWERWASH=1\n")
metadata["ota-wipe"] = "yes"
- # Add the signed payload file and properties into the zip.
- common.ZipWrite(output_zip, properties_file, arcname="payload_properties.txt")
+ # Add the signed payload file and properties into the zip. In order to
+ # support streaming, we pack payload.bin, payload_properties.txt and
+ # care_map.txt as ZIP_STORED. So these entries can be read directly with
+ # the offset and length pairs.
common.ZipWrite(output_zip, signed_payload_file, arcname="payload.bin",
compress_type=zipfile.ZIP_STORED)
- WriteMetadata(metadata, output_zip)
+ common.ZipWrite(output_zip, properties_file,
+ arcname="payload_properties.txt",
+ compress_type=zipfile.ZIP_STORED)
# If dm-verity is supported for the device, copy contents of care_map
# into A/B OTA package.
@@ -1377,16 +1400,43 @@
namelist = target_zip.namelist()
if care_map_path in namelist:
care_map_data = target_zip.read(care_map_path)
- common.ZipWriteStr(output_zip, "care_map.txt", care_map_data)
+ common.ZipWriteStr(output_zip, "care_map.txt", care_map_data,
+ compress_type=zipfile.ZIP_STORED)
else:
print("Warning: cannot find care map file in target_file package")
common.ZipClose(target_zip)
- # Sign the whole package to comply with the Android OTA package format.
+ # SignOutput(), which in turn calls signapk.jar, will possibly reorder the
+ # zip entries, as well as padding the entry headers. We sign the current
+ # package (without the metadata entry) to allow that to happen. Then compute
+ # the zip entry offsets, write the metadata and do the signing again.
common.ZipClose(output_zip)
- SignOutput(temp_zip_file.name, output_file)
+ temp_signing = tempfile.NamedTemporaryFile()
+ SignOutput(temp_zip_file.name, temp_signing.name)
temp_zip_file.close()
+ # Open the signed zip. Compute the metadata that's needed for streaming.
+ output_zip = zipfile.ZipFile(temp_signing, "a",
+ compression=zipfile.ZIP_DEFLATED)
+ metadata['streaming-property-files'] = ComputeStreamingMetadata(output_zip)
+
+ # Write the metadata entry into the zip.
+ WriteMetadata(metadata, output_zip)
+ common.ZipClose(output_zip)
+
+ # Re-sign the package after adding the metadata entry, which should not
+ # affect the entries that are needed for streaming. Because signapk packs
+ # ZIP_STORED entries first, then the ZIP_DEFLATED entries such as metadata.
+ SignOutput(temp_signing.name, output_file)
+ temp_signing.close()
+
+ # Reopen the signed zip to double check the streaming metadata.
+ output_zip = zipfile.ZipFile(output_file, "r")
+ assert (metadata['streaming-property-files'] ==
+ ComputeStreamingMetadata(output_zip)), \
+ "Mismatching streaming metadata."
+ common.ZipClose(output_zip)
+
class FileDifference(object):
def __init__(self, partition, source_zip, target_zip, output_zip):