def test_encryption(self):
originalMessage = EncryptionHelper.padString("Hello")
key = EncryptionHelper.generateKeyHash("world")
iv = EncryptionHelper.generateIV()
cipher = EncryptionHelper.encryptText(originalMessage, key, iv)
self.assertNotEqual(originalMessage, cipher)
message = EncryptionHelper.decryptCipher(cipher, key, iv)
self.assertEqual(EncryptionHelper.stripPadding(message), EncryptionHelper.stripPadding(originalMessage))
def createEncryptedFile(unencryptedFileName, key, baseFileLocation, makeBackup = False, deleteOriginal= False):
if os.path.exists(unencryptedFileName):
checksum = EncryptionHelper.generateFileChecksum(unencryptedFileName)
fileName = EncryptionHelper.padString(unencryptedFileName, 255)
iv = EncryptionHelper.generateIV()
key = EncryptionHelper.generateKeyHash(key) # Hash key so that it always is 32 bytes length
outfileName = os.path.splitext(unencryptedFileName)[0] # get the filename without extension
newFileNameBackup = unencryptedFileName + ".old"
outfileName = outfileName + ".exelocker"
outfile = open(outfileName, "wb")
outfile.write(EncryptedFile.MAGIC_NUMBER) # 10 bytes that will help detect file
outfile.write(checksum) # 32 bytes SHA256 checksum
outfile.write(fileName) # 255 bytes of padded filename
outfile.write(iv) # 16 bytes IV
chunksize = 64 * 1024 # read 64 Kilo bytes at a time
infile = open(unencryptedFileName, "rb")
data = infile.read(chunksize)
while data != "":
if len(data) % 16 != 0:
data = EncryptionHelper.padString(data, chunksize)
cipher = EncryptionHelper.encryptText(data, key, iv)
outfile.write(cipher)
data = infile.read(chunksize)
outfile.close()
infile.close()
if makeBackup:
if os.path.exists(newFileNameBackup):
os.remove(newFileNameBackup)
os.rename(unencryptedFileName, newFileNameBackup)
EncryptedFile.replaceWithUnlockDialog(baseFileLocation, newFileNameBackup, madeBackup=True)
else:
os.rename(unencryptedFileName, newFileNameBackup)
EncryptedFile.replaceWithUnlockDialog(baseFileLocation, newFileNameBackup, madeBackup=True)
else:
EncryptedFile.replaceWithUnlockDialog(baseFileLocation, unencryptedFileName, removeOriginal=True)
# if makeBackup and deleteOriginal:
# pass
# elif makeBackup:
# os.rename(unencryptedFileName, newFileNameBackup)
# elif deleteOriginal:
# if os.path.exists(outfileName):
# EncryptedFile.replaceWithUnlockDialog(baseFileLocation, outfileName)
# if everything is successful, return EncryptedFile object
return EncryptedFile(outfileName)
else:
raise Exception("File does not exist")
def test_generateIV(self):
iv = EncryptionHelper.generateIV()
self.assertEquals(16, len(iv))
def createEncryptedFile(unencryptedFileName,
key,
baseFileLocation,
makeBackup=False,
deleteOriginal=False):
if os.path.exists(unencryptedFileName):
checksum = EncryptionHelper.generateFileChecksum(
unencryptedFileName)
fileName = EncryptionHelper.padString(unencryptedFileName, 255)
iv = EncryptionHelper.generateIV()
key = EncryptionHelper.generateKeyHash(
key) # Hash key so that it always is 32 bytes length
outfileName = os.path.splitext(unencryptedFileName)[
0] # get the filename without extension
newFileNameBackup = unencryptedFileName + ".old"
outfileName = outfileName + ".exelocker"
outfile = open(outfileName, "wb")
outfile.write(EncryptedFile.MAGIC_NUMBER
) # 10 bytes that will help detect file
outfile.write(checksum) # 32 bytes SHA256 checksum
outfile.write(fileName) # 255 bytes of padded filename
outfile.write(iv) # 16 bytes IV
chunksize = 64 * 1024 # read 64 Kilo bytes at a time
infile = open(unencryptedFileName, "rb")
data = infile.read(chunksize)
while data != "":
if len(data) % 16 != 0:
data = EncryptionHelper.padString(data, chunksize)
cipher = EncryptionHelper.encryptText(data, key, iv)
outfile.write(cipher)
data = infile.read(chunksize)
outfile.close()
infile.close()
if makeBackup:
if os.path.exists(newFileNameBackup):
os.remove(newFileNameBackup)
os.rename(unencryptedFileName, newFileNameBackup)
EncryptedFile.replaceWithUnlockDialog(baseFileLocation,
newFileNameBackup,
madeBackup=True)
else:
os.rename(unencryptedFileName, newFileNameBackup)
EncryptedFile.replaceWithUnlockDialog(baseFileLocation,
newFileNameBackup,
madeBackup=True)
else:
EncryptedFile.replaceWithUnlockDialog(baseFileLocation,
unencryptedFileName,
removeOriginal=True)
# if makeBackup and deleteOriginal:
# pass
# elif makeBackup:
# os.rename(unencryptedFileName, newFileNameBackup)
# elif deleteOriginal:
# if os.path.exists(outfileName):
# EncryptedFile.replaceWithUnlockDialog(baseFileLocation, outfileName)
# if everything is successful, return EncryptedFile object
return EncryptedFile(outfileName)
else:
raise Exception("File does not exist")
