def _prepare_index(self):
# Add space for file size
self.index_offset += 8
# Space for num_signatures & num_additional_sections
self.index_offset += 4 + 4
# Write the magic and placeholder for the index
self.fileobj.write(b"MAR1" + packint(self.index_offset))
# Write placeholder for file size
self.fileobj.write(struct.pack(">Q", 0))
# Write num_signatures
self.fileobj.write(packint(len(self.signature_versions)))
# Write placeholder signatures
for algo_id, keyfile in self.signature_versions:
sig = MarSignature(algo_id, keyfile)
sig._offset = self.index_offset
self.index_offset += sig.size
self.signatures.append(sig)
# algoid
self.fileobj.write(packint(algo_id))
# numbytes
self.fileobj.write(packint(sig.sigsize))
# space for signature
self.fileobj.write("\0" * sig.sigsize)
# Write placeholder for number of additional sections
self.fileobj.write(packint(0))
def _prepare_index(self):
# Add space for file size
self.index_offset += 8
# Space for num_signatures & num_additional_sections
self.index_offset += 4 + 4
# Write the magic and placeholder for the index
self.fileobj.write(b"MAR1" + packint(self.index_offset))
# Write placeholder for file size
self.fileobj.write(struct.pack(">Q", 0))
# Write num_signatures
self.fileobj.write(packint(len(self.signature_versions)))
# Write placeholder signatures
for algo_id, keyfile in self.signature_versions:
sig = MarSignature(algo_id, keyfile)
sig._offset = self.index_offset
self.index_offset += sig.size
self.signatures.append(sig)
# algoid
self.fileobj.write(packint(algo_id))
# numbytes
self.fileobj.write(packint(sig.sigsize))
# space for signature
self.fileobj.write("\0" * sig.sigsize)
# Write placeholder for number of additional sections
self.fileobj.write(packint(0))
def _read_signatures(self):
fp = self.fileobj
log.debug("reading signatures")
fp.seek(8)
file_size = unpacklongint(fp.read(8))
# Check that the file size matches
fp.seek(0, 2)
assert fp.tell() == file_size
fp.seek(16)
num_sigs = unpackint(fp.read(4))
log.debug("file_size: %i bytes", file_size)
log.debug("%i signatures present", num_sigs)
signatures = []
for i in range(num_sigs):
sig = MarSignature.from_fileobj(fp)
for algo_id, keyfile in self.signature_versions:
if algo_id == sig.algo_id:
sig.keyfile = keyfile
break
else:
log.info("no key specified to validate %i"
" signature", sig.algo_id)
signatures.append(sig)
# Read additional sections; this is also only present if we have a
# signature block
num_additional_sections = unpackint(fp.read(4))
log.debug("%i additional sections present",
num_additional_sections)
for i in range(num_additional_sections):
info = AdditionalInfo.from_fileobj(fp)
log.debug("%s", info)
self.additional_info.append(info)
return signatures
def _read_signatures(self):
fp = self.fileobj
log.debug("reading signatures")
fp.seek(8)
file_size = unpacklongint(fp.read(8))
# Check that the file size matches
fp.seek(0, 2)
assert fp.tell() == file_size
fp.seek(16)
num_sigs = unpackint(fp.read(4))
log.debug("file_size: %i bytes", file_size)
log.debug("%i signatures present", num_sigs)
signatures = []
for i in range(num_sigs):
sig = MarSignature.from_fileobj(fp)
for algo_id, keyfile in self.signature_versions:
if algo_id == sig.algo_id:
sig.keyfile = keyfile
break
else:
log.info("no key specified to validate %i"
" signature", sig.algo_id)
signatures.append(sig)
# Read additional sections; this is also only present if we have a
# signature block
num_additional_sections = unpackint(fp.read(4))
log.debug("%i additional sections present",
num_additional_sections)
for i in range(num_additional_sections):
info = AdditionalInfo.from_fileobj(fp)
log.debug("%s", info)
self.additional_info.append(info)
return signatures
