def __init__(self, major_version):
self._header = FakeHeader(major_version, 222, 0)
self.header = None
self._manifest = FakeManifest(major_version)
self.manifest = None
self._blobs = {}
self._payload_signatures = update_metadata_pb2.Signatures()
self._metadata_signatures = update_metadata_pb2.Signatures()
def Init(self):
"""Initializes the payload object.
This is a prerequisite for any other public API call.
Raises:
PayloadError if object already initialized or fails to initialize
correctly.
"""
if self.is_init:
raise PayloadError('payload object already initialized')
self.manifest_hasher = hashlib.sha256()
# Read the file header.
self.payload_file.seek(self.payload_file_offset)
self.header = self._ReadHeader()
# Read the manifest.
manifest_raw = self._ReadManifest()
self.manifest = update_metadata_pb2.DeltaArchiveManifest()
self.manifest.ParseFromString(manifest_raw)
# Read the metadata signature (if any).
metadata_signature_raw = self._ReadMetadataSignature()
if metadata_signature_raw:
self.metadata_signature = update_metadata_pb2.Signatures()
self.metadata_signature.ParseFromString(metadata_signature_raw)
self.metadata_size = self.header.size + self.header.manifest_len
self.data_offset = self.metadata_size + self.header.metadata_signature_len
self.is_init = True
def _DisplaySignaturesBlob(signature_name, signatures_blob):
from update_payload import update_metadata_pb2
signatures = update_metadata_pb2.Signatures()
signatures.ParseFromString(signatures_blob)
print('%s signatures: (%d entries)' %
(signature_name, len(signatures.signatures)))
for signature in signatures.signatures:
print(
' version=%s, hex_data: (%d bytes)' %
(signature.version if signature.HasField('version') else None,
len(signature.data)))
DisplayHexData(signature.data, indent=4)
def __init__(self): self.sigs = update_metadata_pb2.Signatures()