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 __init__(self, encryptedFileName):
if os.path.exists(encryptedFileName) and EncryptedFile.isValidFile(encryptedFileName):
self.encryptedFileName = encryptedFileName
self._handle = open(encryptedFileName, "rb")
self._handle.read(10) # skip reading magic number
self._checksum = self._handle.read(32) # read 32 bytes checksum from file
self._filename = EncryptionHelper.stripPadding(self._handle.read(255)) # read filename
# and then strip padding
self._iv = self._handle.read(16) # read 16 bytes IV
self._cycles = (os.stat(encryptedFileName).st_size) / (64 * 1024) # divided by 64kbytes
else:
raise Exception("File does not exist or not a valid EXELocker File.")
def decryptFile(self, key, sameLocation = False):
if sameLocation == False:
outfile = open(self.getOriginalFileName(), "wb")
else:
outfileName = os.path.join(os.path.dirname(self.encryptedFileName), self.getOriginalFileName())
outfile = open(outfileName, "wb")
# change the name of the encryptedFileName because right now it will be .exelocker file, change it to original extension
data = self._handle.read(EncryptedFile._CHUNK_SIZE)
cycle = 1
while data != "":
message = EncryptionHelper.decryptCipher(data, key, self._iv)
if cycle == self._cycles:
message = EncryptionHelper.stripPadding(message)
outfile.write(message)
cycle = cycle + 1
data = self._handle.read(EncryptedFile._CHUNK_SIZE)
outfile.close()
def __init__(self, encryptedFileName):
if os.path.exists(encryptedFileName) and EncryptedFile.isValidFile(
encryptedFileName):
self.encryptedFileName = encryptedFileName
self._handle = open(encryptedFileName, "rb")
self._handle.read(10) # skip reading magic number
self._checksum = self._handle.read(
32) # read 32 bytes checksum from file
self._filename = EncryptionHelper.stripPadding(
self._handle.read(255)) # read filename
# and then strip padding
self._iv = self._handle.read(16) # read 16 bytes IV
self._cycles = (os.stat(encryptedFileName).st_size) / (
64 * 1024) # divided by 64kbytes
else:
raise Exception(
"File does not exist or not a valid EXELocker File.")
def decryptFile(self, key, sameLocation=False):
if sameLocation == False:
outfile = open(self.getOriginalFileName(), "wb")
else:
outfileName = os.path.join(os.path.dirname(self.encryptedFileName),
self.getOriginalFileName())
outfile = open(outfileName, "wb")
# change the name of the encryptedFileName because right now it will be .exelocker file, change it to original extension
data = self._handle.read(EncryptedFile._CHUNK_SIZE)
cycle = 1
while data != "":
message = EncryptionHelper.decryptCipher(data, key, self._iv)
if cycle == self._cycles:
message = EncryptionHelper.stripPadding(message)
outfile.write(message)
cycle = cycle + 1
data = self._handle.read(EncryptedFile._CHUNK_SIZE)
outfile.close()
def test_stripPadding(self):
originalString = "hello"
paddedString = EncryptionHelper.padString("hello")
self.assertNotEqual(originalString, paddedString)
self.assertEquals(originalString, EncryptionHelper.stripPadding(paddedString))
