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# -*- tab-width: 4; indent-tabs-mode: nil -*-
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
#
from . import globals
class EncryptionInfo(object):
class Type:
Unknown = -1
Standard = 0
Extensible = 1
Agile = 2
def __init__ (self, bytes):
self.strm = globals.ByteStream(bytes)
self.type = EncryptionInfo.Type.Unknown
self.size = -1
def read (self):
self.major = self.strm.readUnsignedInt(2)
self.minor = self.strm.readUnsignedInt(2)
if self.major == 3 or self.major == 4:
if self.minor == 2:
self.type = EncryptionInfo.Type.Standard
elif self.minor == 3:
self.type = EncryptionInfo.Type.Extensible
elif self.minor == 4:
self.type = EncryptionInfo.Type.Agile
flag = self.strm.readUnsignedInt(4)
self.fCryptoAPI = (flag & 0x00000004) != 0 # C
self.fDocProps = (flag & 0x00000008) != 0 # D (false if document properties are encrypted.)
self.fExternal = (flag & 0x00000010) != 0 # E (extensible encryption used)
self.fAES = (flag & 0x00000020) != 0 # F (ECMA-376 document)
if self.type == EncryptionInfo.Type.Standard or self.type == EncryptionInfo.Type.Extensible:
self.size = self.strm.readUnsignedInt(4)
elif self.type == EncryptionInfo.Type.Agile:
self.bytes = self.strm.readRemainingBytes()
def outputBoolean (self, name, value):
if value:
bs = "true"
else:
bs = "false"
print ("%s: %s"%(name, bs))
def outputInt (self, name, value):
print ("%s: %d"%(name, value))
def output (self):
print ("version: %d.%d"%(self.major, self.minor))
self.outputBoolean("crypto API", self.fCryptoAPI)
self.outputBoolean("encrypted document properties", not self.fDocProps)
self.outputBoolean("extensible encryption", self.fExternal)
self.outputBoolean("ECMA-376 document", self.fAES)
if self.type == EncryptionInfo.Type.Standard:
self.outputStandard()
elif self.type == EncryptionInfo.Type.Extensible:
self.outputExtensible()
elif self.type == EncryptionInfo.Type.Agile:
self.outputAgile()
def outputStandard (self):
self.outputInt("header stream size", self.size)
def outputExtensible (self):
self.outputInt("header stream size", self.size)
def outputAgile (self):
print (self.bytes)
# vim:set filetype=python shiftwidth=4 softtabstop=4 expandtab:
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