def test1(self):
padded = pad(b(""), 4)
self.assertTrue(padded == uh(b("04040404")))
padded = pad(b(""), 4, 'pkcs7')
self.assertTrue(padded == uh(b("04040404")))
back = unpad(padded, 4)
self.assertTrue(back == b(""))
def test1(self):
padded = pad(b(""), 4)
self.failUnless(padded == uh(b("04040404")))
padded = pad(b(""), 4, 'pkcs7')
self.failUnless(padded == uh(b("04040404")))
back = unpad(padded, 4)
self.failUnless(back == b(""))
def load_encrypted_keydata(self, keydata):
"""Load a key from encrypted keydata (in PEM format)."""
lines = keydata.strip().replace(' ', '').splitlines()
if not lines[1].startswith('Proc-Type:4,ENCRYPTED'):
raise TypeError('Unsupported encryption')
dek = lines[2].split(':')
if len(dek) != 2 or dek[0] != 'DEK-Info':
raise ValueError('PEM encryption method not supported')
algo, salt = dek[1].split(',')
salt = salt.decode('hex')
if algo == 'DES-CBC':
key = PBKDF1(self.passphrase, salt, 8, 1, MD5)
obj = DES.new(key, DES.MODE_CBC, salt)
elif algo == 'DES-EDE3-CBC':
key = PBKDF1(self.passphrase, salt, 16, 1, MD5)
key+= PBKDF1(key + passphrase, salt, 8, 1, MD5)
obj = DES3.new(key, DES3.MOE_CBC, salt)
elif algo == 'AES-128-CBC':
key = PBKDF1(self.passphrase, salt[:8], 16, 1, MD5)
obj = AES.new(key, AES.MODE_CBC, salt)
else:
raise TypeError('%s: cipher not supported' % (algo,))
lines = lines[3:-1]
data = base64.b64decode(''.join(lines))
return unpad(obj.decrypt(data), obj.block_size)
def decrypt(self, file_path):
if not os.path.exists(file_path):
raise ValueError('Input file path not exists: %s ', file_path)
with open(file_path, 'rb') as f:
data_to_decrypt = f.read()
return unpad(self.cipher.decrypt(data_to_decrypt), self.multiple_of_byte)
def decrypt(self, encrypt_string):
if self.use_urlsafe:
encrypt_byte_string = base64.urlsafe_b64decode(bytes(map(ord, encrypt_string)))
else:
encrypt_byte_string = base64.b64decode(bytes(map(ord, encrypt_string)))
pad_byte_string = self.cipher.decrypt(encrypt_byte_string)
string = unpad(pad_byte_string, self.multiple_of_byte).decode('utf-8')
return string
def decrypt(data, passphrase):
"""Decrypt a piece of data using a passphrase and *PBES1*.
The algorithm to use is automatically detected.
:Parameters:
data : byte string
The piece of data to decrypt.
passphrase : byte string
The passphrase to use for decrypting the data.
:Returns:
The decrypted data, as a binary string.
"""
encrypted_private_key_info = decode_der(DerSequence, data)
encrypted_algorithm = decode_der(
DerSequence,
encrypted_private_key_info[0]
)
encrypted_data = decode_der(
DerOctetString,
encrypted_private_key_info[1]
).payload
pbe_oid = decode_der(DerObjectId, encrypted_algorithm[0]).value
cipher_params = {}
if pbe_oid == "1.2.840.113549.1.5.3":
# PBE_MD5_DES_CBC
hashmod = MD5
ciphermod = DES
elif pbe_oid == "1.2.840.113549.1.5.6":
# PBE_MD5_RC2_CBC
hashmod = MD5
ciphermod = ARC2
cipher_params['effective_keylen'] = 64
elif pbe_oid == "1.2.840.113549.1.5.10":
# PBE_SHA1_DES_CBC
hashmod = SHA1
ciphermod = DES
elif pbe_oid == "1.2.840.113549.1.5.11":
# PBE_SHA1_RC2_CBC
hashmod = SHA1
ciphermod = ARC2
cipher_params['effective_keylen'] = 64
else:
raise PbesError("Unknown OID for PBES1")
pbe_params = decode_der(DerSequence, encrypted_algorithm[1])
salt = decode_der(DerOctetString, pbe_params[0]).payload
iterations = pbe_params[1]
key_iv = PBKDF1(passphrase, salt, 16, iterations, hashmod)
key, iv = key_iv[:8], key_iv[8:]
cipher = ciphermod.new(key, ciphermod.MODE_CBC, iv, **cipher_params)
pt = cipher.decrypt(encrypted_data)
return unpad(pt, cipher.block_size)
def decrypt(self, encrypt_string):
self.cipher = self.gen_cipher()
if self.use_urlsafe:
encrypt_byte_string = base64.urlsafe_b64decode(bytes(map(ord, encrypt_string)))
else:
encrypt_byte_string = base64.b64decode(bytes(map(ord, encrypt_string)))
pad_byte_string = self.cipher.decrypt(encrypt_byte_string)
original_string = unpad(pad_byte_string, AES.block_size).decode('utf-8')
return original_string
def file_decrypt(password, file_path, output_file_path):
key = generate_key(password)
# 使用ECB模式进行加密解密
cipher = AES.new(key, AES.MODE_ECB)
# 设置加密解密时分块读取10240KB
read_kb = 10240
block_size = read_kb * 1024
data_handle_func = cipher.decrypt
# 读取到文件尾部时，执行解密后尾部去除补位
data_end_handle_func = lambda d: unpad(cipher.decrypt(d), MULTIPLE_OF_BYTE)
file_handle(file_path, output_file_path, block_size, data_handle_func, data_end_handle_func)
# A: msg_a_t = Alice, Bob, Ra
msg_a_t = []
msg_a_t.append("Alice")
msg_a_t.append("Bob")
msg_a_t.append(a_random.hex())
json_a_t = json.dumps(msg_a_t)
# A->T: msg_a_t
print("A->T: " + json_a_t)
socket.enviar(json_a_t.encode("utf-8"))
# T->A: E_AT(Ra, Bob, K_AB, E_BT(K_AB, Alice))
# A: Descifrar msg_t_a
datos = socket.recibir()
decipher_aes_a_t = AES.new(key_a_t, AES.MODE_ECB)
json_t_a = unpad(decipher_aes_a_t.decrypt(datos),
BLOCK_SIZE_AES).decode("utf-8")
print("T->A (Clear): " + json_t_a)
msg_t_a = json.loads(json_t_a)
# A: Comprobar campos de msg_t_a
t_random, t_bob, t_k_ab, t_bt = msg_t_a
t_random = bytearray.fromhex(t_random)
t_k_ab = bytearray.fromhex(t_k_ab)
if (a_random != t_random):
print("ERROR: Nonce Equivocado")
socket.cerrar()
exit()
if (a_bob != t_bob):
print("ERROR: Receptor incorrecto")
socket.cerrar()
exit()
def decryptCBC(ciphertext, key):
cipher = AES.new(key, AES.MODE_CBC, iv)
plaintext = cipher.decrypt(ciphertext)
return unpad(plaintext, AES.block_size)
def response(flow: http.HTTPFlow):
global MSLAESKey
global ClientPublicKey
global ProxyRSAKey
if isPathEvaluator(flow.request.pretty_url):
logging.info("Netflix pathEvaluator response: " +
flow.request.pretty_url)
if IS_PYTHON2:
logging.info(
unquote(flow.request.content.decode('utf-8')).decode('utf-8'))
else:
logging.info(unquote(flow.request.content.decode('utf-8')))
if isMSLAPI(flow.request.pretty_url):
logging.info("Netflix msl response: " + flow.request.pretty_url)
parsedResponse = None
parsedRespChunks = []
headerEndOffset = -1
try:
parsedResponse = json.loads(flow.response.content)
except json.JSONDecodeError as e:
headerEndOffset = e.pos
parsedResponse = json.loads(flow.response.content[0:e.pos])
appendChunk(parsedRespChunks, flow.response.content[e.pos:])
#logging.info(flow.response.content.decode())
if not "headerdata" in parsedResponse.keys():
return
headerData = b64decode(parsedResponse["headerdata"])
#logging.info(headerData.decode())
parsedHeaderData = json.loads(headerData)
if "keyresponsedata" in parsedHeaderData.keys():
hmacKeyEncStr = parsedHeaderData["keyresponsedata"]["keydata"][
"hmackey"]
encKeyEncStr = parsedHeaderData["keyresponsedata"]["keydata"][
"encryptionkey"]
proxyCipher = PKCS1_OAEP.new(ProxyRSAKey)
clientCipher = PKCS1_OAEP.new(ClientPublicKey)
global MSLAESKey
if Mechanism == "JWK_RSA":
hmacKeyEnv = proxyCipher.decrypt(b64decode(hmacKeyEncStr))
encKeyEnv = proxyCipher.decrypt(b64decode(encKeyEncStr))
hmacKeyEncStr = b64encode(
clientCipher.encrypt(hmacKeyEnv)).decode()
encKeyEncStr = b64encode(
clientCipher.encrypt(encKeyEnv)).decode()
MSLAESKey = b64urldecode(json.loads(encKeyEnv)["k"])
logging.info("MSL AES key: " + json.loads(encKeyEnv)["k"])
updateSession()
elif Mechanism == "JWEJS_RSA":
hmacKeyJWEJS = json.loads(b64decode(hmacKeyEncStr))
encKeyJWEJS = json.loads(b64decode(encKeyEncStr))
logging.info("encryptionkey before: " +
b64decode(encKeyEncStr).decode())
logging.info("hmackey before: " +
b64decode(hmacKeyEncStr).decode())
encKey = proxyCipher.decrypt(
b64urldecode(
encKeyJWEJS["recipients"][0]["encrypted_key"]))
gcmCipher = AES.new(
encKey, AES.MODE_GCM,
b64urldecode(encKeyJWEJS["initialization_vector"]))
encKeyPlain = gcmCipher.decrypt(
b64urldecode(encKeyJWEJS["ciphertext"])).decode()
#logging.info("JWEJS message: " + encKeyPlain)
MSLAESKey = b64urldecode(json.loads(encKeyPlain)["k"])
logging.info("MSL AES key: " + json.loads(encKeyPlain)["k"])
updateSession()
encKeyJWEJS["recipients"][0]["encrypted_key"] = b64urlencode(
clientCipher.encrypt(encKey)).decode()
gcmCipher = AES.new(
encKey, AES.MODE_GCM,
b64urldecode(encKeyJWEJS["initialization_vector"]))
aad = encKeyJWEJS["recipients"][0][
"header"] + "." + encKeyJWEJS["recipients"][0][
"encrypted_key"] + "." + encKeyJWEJS[
"initialization_vector"]
gcmCipher.update(aad.encode())
cip, tag = gcmCipher.encrypt_and_digest(encKeyPlain.encode())
#logging.info("expected ciphertext: " + b64urlencode(cip).decode())
#logging.info("expected integrity_value: " + b64urlencode(tag).decode())
encKeyJWEJS["recipients"][0]["integrity_value"] = b64urlencode(
tag).decode()
encKeyJWEJS_str = json.dumps(encKeyJWEJS)
encKeyJWEJS_str = re.sub(r'[\s+]', '', encKeyJWEJS_str)
encKeyEncStr = b64encode(encKeyJWEJS_str.encode()).decode()
hmacKey = proxyCipher.decrypt(
b64urldecode(
hmacKeyJWEJS["recipients"][0]["encrypted_key"]))
gcmCipher = AES.new(
hmacKey, AES.MODE_GCM,
b64urldecode(hmacKeyJWEJS["initialization_vector"]))
hmacKeyPlain = gcmCipher.decrypt(
b64urldecode(hmacKeyJWEJS["ciphertext"])).decode()
hmacKeyJWEJS["recipients"][0]["encrypted_key"] = b64urlencode(
clientCipher.encrypt(hmacKey)).decode()
gcmCipher = AES.new(
hmacKey, AES.MODE_GCM,
b64urldecode(hmacKeyJWEJS["initialization_vector"]))
aad = hmacKeyJWEJS["recipients"][0][
"header"] + "." + hmacKeyJWEJS["recipients"][0][
"encrypted_key"] + "." + hmacKeyJWEJS[
"initialization_vector"]
gcmCipher.update(aad.encode())
cip, tag = gcmCipher.encrypt_and_digest(hmacKeyPlain.encode())
#logging.info("expected ciphertext: " + b64urlencode(cip).decode())
#logging.info("expected integrity_value: " + b64urlencode(tag).decode())
hmacKeyJWEJS["recipients"][0][
"integrity_value"] = b64urlencode(tag).decode()
hmacKeyJWEJS_str = json.dumps(hmacKeyJWEJS)
hmacKeyJWEJS_str = re.sub(r'[\s+]', '', hmacKeyJWEJS_str)
hmacKeyEncStr = b64encode(hmacKeyJWEJS_str.encode()).decode()
logging.info("encryptionkey after: " + encKeyJWEJS_str)
logging.info("hmackey after: " + hmacKeyJWEJS_str)
#logging.info("Signature after: " + parsedResponse["signature"])
parsedHeaderData["keyresponsedata"]["keydata"][
"hmackey"] = hmacKeyEncStr
parsedHeaderData["keyresponsedata"]["keydata"][
"encryptionkey"] = encKeyEncStr
headerDataModified = json.dumps(parsedHeaderData).encode()
parsedResponse["headerdata"] = b64encode(
headerDataModified).decode()
#logging.info("Signature before: " + parsedResponse["signature"])
headerDataHash = SHA256.new(headerDataModified)
parsedResponse["signature"] = b64encode(
pkcs1_15.new(ProxySignKey).sign(headerDataHash)).decode()
contentRest = b""
if headerEndOffset != -1:
contentRest = flow.response.content[headerEndOffset:]
flow.response.content = json.dumps(
parsedResponse).encode() + contentRest
#logging.info(b64decode(parsedResponse["headerdata"]).decode())
#logging.info(flow.response.content.decode())
elif "ciphertext" in parsedHeaderData.keys() and MSLAESKey is not None:
iv = b64decode(parsedHeaderData["iv"])
cipher = AES.new(MSLAESKey, AES.MODE_CBC, iv)
cipherText = b64decode(parsedHeaderData["ciphertext"])
try:
plainText = unpad(cipher.decrypt(cipherText), 16)
logging.info(plainText.decode())
except ValueError:
logging.error("Error: incorrect AES key")
#logging.info("Number of chunks: " + str(len(parsedRespChunks)))
for chunk in parsedRespChunks:
if MSLAESKey is None:
continue
payload = json.loads(b64decode(chunk["payload"]))
iv = b64decode(payload["iv"])
cipher = AES.new(MSLAESKey, AES.MODE_CBC, iv)
cipherText = b64decode(payload["ciphertext"])
try:
plainText = unpad(cipher.decrypt(cipherText), 16)
except ValueError:
logging.error("Error: incorrect AES key")
continue
plainJSON = None
try:
plainJSON = json.loads(plainText)
except json.JSONDecodeError as e:
plainJSON = json.loads(plainText[0:e.pos])
#logging.info(plainText.decode())
decoded = b64decode(plainJSON["data"])
if "compressionalgo" in plainJSON.keys():
if plainJSON["compressionalgo"] == "GZIP":
decoded = gzip.decompress(decoded)
elif plainJSON["compressionalgo"] == "LZW":
decoded = lzw_decompress(decoded)
logging.info(decoded.decode())
elif "/cadmium-playercore" in flow.request.pretty_url:
logging.info("Netflix cadmium player response")
proxySignKeyStr = b64encode(ProxySignKey.publickey().exportKey("DER"))
flow.response.content = flow.response.content.replace(
ServerSignPubKey.encode(),
proxySignKeyStr).replace(ServerSignPubKey2.encode(),
proxySignKeyStr)
def test1(self):
padded = pad(b(""), 4, 'iso7816')
self.failUnless(padded == uh(b("80000000")))
back = unpad(padded, 4, 'iso7816')
self.failUnless(back == b(""))
def test1(self):
padded = pad(b(""), 4, 'x923')
self.failUnless(padded == uh(b("00000004")))
back = unpad(padded, 4, 'x923')
self.failUnless(back == b(""))
def decode(pem_data, passphrase=None):
"""Decode a PEM block into binary.
:Parameters:
pem_data : string
The PEM block.
passphrase : byte string
If given and the PEM block is encrypted,
the key will be derived from the passphrase.
:Returns:
A tuple with the binary data, the marker string, and a boolean to
indicate if decryption was performed.
:Raises ValueError:
If decoding fails, if the PEM file is encrypted and no passphrase has
been provided or if the passphrase is incorrect.
"""
# Verify Pre-Encapsulation Boundary
r = re.compile("\s*-----BEGIN (.*)-----\n")
m = r.match(pem_data)
if not m:
raise ValueError("Not a valid PEM pre boundary")
marker = m.group(1)
# Verify Post-Encapsulation Boundary
r = re.compile("-----END (.*)-----\s*$")
m = r.search(pem_data)
if not m or m.group(1) != marker:
raise ValueError("Not a valid PEM post boundary")
# Removes spaces and slit on lines
lines = pem_data.replace(" ", '').split()
# Decrypts, if necessary
if lines[1].startswith('Proc-Type:4,ENCRYPTED'):
if not passphrase:
raise ValueError("PEM is encrypted, but no passphrase available")
DEK = lines[2].split(':')
if len(DEK) != 2 or DEK[0] != 'DEK-Info':
raise ValueError("PEM encryption format not supported.")
algo, salt = DEK[1].split(',')
salt = unhexlify(tobytes(salt))
if algo == "DES-CBC":
# This is EVP_BytesToKey in OpenSSL
key = PBKDF1(passphrase, salt, 8, 1, MD5)
objdec = DES.new(key, DES.MODE_CBC, salt)
elif algo == "DES-EDE3-CBC":
# Note that EVP_BytesToKey is note exactly the same as PBKDF1
key = PBKDF1(passphrase, salt, 16, 1, MD5)
key += PBKDF1(key + passphrase, salt, 8, 1, MD5)
objdec = DES3.new(key, DES3.MODE_CBC, salt)
elif algo == "AES-128-CBC":
key = PBKDF1(passphrase, salt[:8], 16, 1, MD5)
objdec = AES.new(key, AES.MODE_CBC, salt)
else:
raise ValueError("Unsupport PEM encryption algorithm.")
lines = lines[2:]
else:
objdec = None
# Decode body
data = a2b_base64(b(''.join(lines[1:-1])))
enc_flag = False
if objdec:
data = unpad(objdec.decrypt(data), objdec.block_size)
enc_flag = True
return (data, marker, enc_flag)
def decrypt(data, passphrase):
"""Decrypt a piece of data using a passphrase and *PBES2*.
The algorithm to use is automatically detected.
:Parameters:
data : byte string
The piece of data to decrypt.
passphrase : byte string
The passphrase to use for decrypting the data.
:Returns:
The decrypted data, as a binary string.
"""
enc_private_key_info = DerSequence().decode(data, nr_elements=2)
enc_algo = DerSequence().decode(enc_private_key_info[0])
encrypted_data = DerOctetString().decode(enc_private_key_info[1]).payload
pbe_oid = DerObjectId().decode(enc_algo[0]).value
if pbe_oid != _OID_PBES2:
raise PbesError("Not a PBES2 object")
pbes2_params = DerSequence().decode(enc_algo[1], nr_elements=2)
### Key Derivation Function selection
kdf_info = DerSequence().decode(pbes2_params[0], nr_elements=2)
kdf_oid = DerObjectId().decode(kdf_info[0]).value
kdf_key_length = None
# We only support PBKDF2 or scrypt
if kdf_oid == _OID_PBKDF2:
pbkdf2_params = DerSequence().decode(kdf_info[1], nr_elements=(2, 3, 4))
salt = DerOctetString().decode(pbkdf2_params[0]).payload
iteration_count = pbkdf2_params[1]
left = len(pbkdf2_params) - 2
idx = 2
if left > 0:
try:
kdf_key_length = pbkdf2_params[idx] - 0
left -= 1
idx += 1
except TypeError:
pass
# Default is HMAC-SHA1
pbkdf2_prf_oid = "1.2.840.113549.2.7"
if left > 0:
pbkdf2_prf_algo_id = DerSequence().decode(pbkdf2_params[idx])
pbkdf2_prf_oid = DerObjectId().decode(pbkdf2_prf_algo_id[0]).value
elif kdf_oid == _OID_SCRYPT:
scrypt_params = DerSequence().decode(kdf_info[1], nr_elements=(4, 5))
salt = DerOctetString().decode(scrypt_params[0]).payload
iteration_count, scrypt_r, scrypt_p = [scrypt_params[x]
for x in (1, 2, 3)]
if len(scrypt_params) > 4:
kdf_key_length = scrypt_params[4]
else:
kdf_key_length = None
else:
raise PbesError("Unsupported PBES2 KDF")
### Cipher selection
enc_info = DerSequence().decode(pbes2_params[1])
enc_oid = DerObjectId().decode(enc_info[0]).value
if enc_oid == _OID_DES_EDE3_CBC:
# DES_EDE3_CBC
ciphermod = DES3
key_size = 24
elif enc_oid == _OID_AES128_CBC:
# AES128_CBC
ciphermod = AES
key_size = 16
elif enc_oid == _OID_AES192_CBC:
# AES192_CBC
ciphermod = AES
key_size = 24
elif enc_oid == _OID_AES256_CBC:
# AES256_CBC
ciphermod = AES
key_size = 32
else:
raise PbesError("Unsupported PBES2 cipher")
if kdf_key_length and kdf_key_length != key_size:
raise PbesError("Mismatch between PBES2 KDF parameters"
" and selected cipher")
IV = DerOctetString().decode(enc_info[1]).payload
# Create cipher
if kdf_oid == _OID_PBKDF2:
if pbkdf2_prf_oid == _OID_HMAC_SHA1:
hmac_hash_module = SHA1
elif pbkdf2_prf_oid == _OID_HMAC_SHA224:
hmac_hash_module = SHA224
elif pbkdf2_prf_oid == _OID_HMAC_SHA256:
hmac_hash_module = SHA256
elif pbkdf2_prf_oid == _OID_HMAC_SHA384:
hmac_hash_module = SHA384
elif pbkdf2_prf_oid == _OID_HMAC_SHA512:
hmac_hash_module = SHA512
else:
raise PbesError("Unsupported HMAC %s" % pbkdf2_prf_oid)
key = PBKDF2(passphrase, salt, key_size, iteration_count,
hmac_hash_module=hmac_hash_module)
else:
key = scrypt(passphrase, salt, key_size, iteration_count,
scrypt_r, scrypt_p)
cipher = ciphermod.new(key, ciphermod.MODE_CBC, IV)
# Decrypt data
pt = cipher.decrypt(encrypted_data)
return unpad(pt, cipher.block_size)
def decrypt(text):
'''Decrypts data using AES 256'''
cipher = AES.new(key, AES.MODE_ECB)
decrypted_bytes = cipher.decrypt(text)
return unpad(decrypted_bytes, 32).decode('utf-8')
def descifrar(ciphertext):
plaintext = ""
if len(ciphertext) > 0:
cipher = AES.new(key, AES.MODE_ECB)
plaintext = unpad(cipher.decrypt(bytes.fromhex(ciphertext)), AES.block_size).decode('utf-8')
return plaintext
def test4(self):
padded = pad(uh(b("1234567890")), 4, 'x923')
self.failUnless(padded == uh(b("1234567890000003")))
back = unpad(padded, 4, 'x923')
self.failUnless(back == uh(b("1234567890")))
def test3(self):
padded = pad(uh(b("123456")), 4, 'x923')
self.failUnless(padded == uh(b("12345601")))
back = unpad(padded, 4, 'x923')
self.failUnless(back == uh(b("123456")))
def test2(self):
padded = pad(uh(b("12345678")), 4, 'x923')
self.failUnless(padded == uh(b("1234567800000004")))
back = unpad(padded, 4, 'x923')
self.failUnless(back == uh(b("12345678")))
def test3(self):
padded = pad(uh(b("123456")), 4, 'iso7816')
self.failUnless(padded == uh(b("12345680")))
#import pdb; pdb.set_trace()
back = unpad(padded, 4, 'iso7816')
self.failUnless(back == uh(b("123456")))
def D(CTX, KEY):
return unpad(
AES.new(b64decode(KEY), AES.MODE_ECB).decrypt(b64decode(CTX)),
AES.block_size)
def test2(self):
padded = pad(uh(b("12345678")), 4)
self.failUnless(padded == uh(b("1234567804040404")))
back = unpad(padded, 4)
self.failUnless(back == uh(b("12345678")))
from base64 import b64decode
from Crypto.Cipher import AES
from Crypto.Util.Padding import unpad
from Crypto.Hash import SHA256, SHA512
key_digest = '31af112461ca634ea7468e685a6edec4b63a1b1a324a2d77e2172d0d14a84ac455c7448836ec9ab98a614e14487e010ed88ef80f081a7bf911b8e20e04e1c9d7'
iv = b64decode('750dddjhwyJSJ2YhRFZAjw==')
flag = b64decode('L1i39WIWpALQBHZiZWzXdU/mCzwD6pbVZowcJiGUz237mfOBEuYK3/dpJMHq+DP4')
pswd = input('Insert password: '******'You did it: ', pt.decode('utf-8'))
else:
print("lol nope")
def decrypt(self, file_path, output_file_path):
self.cipher = self.gen_cipher()
data_handle_func = self.cipher.decrypt
# 读取到文件尾部时，执行解密后尾部去除补位
data_end_handle_func = lambda d: unpad(self.cipher.decrypt(d), AES.block_size)
self.handle(file_path, output_file_path, data_handle_func, data_end_handle_func)
bit += str(sList[i] & 1)
if (len(bit) == 8):
val = int(bit, 2)
resImg.append(val)
bit = ''
pbar.update(1)
i += 1
pbar.close()
print('Decrypting data...')
while True:
try:
password = getpass()
sha = bytes(hashlib.sha256(bytes(password.encode())).digest())
iv = b'This is an IV456'
cipher = AES.new(sha, AES.MODE_CBC, iv)
dct = unpad(cipher.decrypt(bytes(resImg)), AES.block_size)
break
except ValueError:
print('Entered password is wrong! unable to decrypt.')
resImgList = list(b64decode(dct))
outputImg = np.array(resImgList).reshape((n, m, 3))
print('Writing output to jpg file...')
try:
cv2.imwrite(output, outputImg)
print('Successfully written to file ' + output)
except Exception as inst:
print('Exception caught!')
print(inst.with_traceback)
print(inst.args)
def test4(self):
padded = pad(uh(b("1234567890")), 4, 'x923')
self.assertTrue(padded == uh(b("1234567890000003")))
back = unpad(padded, 4, 'x923')
self.assertTrue(back == uh(b("1234567890")))
def aes_decrypt(
self,
key: str,
iv: str = "00000000000000000000000000000000",
mode: str = "CBC",
hex_key: bool = False,
hex_iv: bool = True,
):
"""Decrypt raw state encrypted with DES.
Advanced Encryption Standard (AES) is a U.S. Federal Information Processing
Standard (FIPS). It was selected after a 5-year process where 15 competing
designs were evaluated.<br><br><b>Key:</b> The following algorithms will
be used based on the size of the
key:
16 bytes = AES-128
24 bytes = AES-192
32 bytes = AES-256
You can generate a password-based key using one of the KDF operations.
IV: The Initialization Vector should be 16 bytes long. If not entered, it will
default to 16 null bytes. Padding: In CBC and ECB mode, PKCS#7 padding will be used.
Args:
key (str): Required. The secret key
iv (str, optional): IV for certain modes only.
Defaults to '00000000000000000000000000000000'.
mode (str, optional): Encryption mode. Defaults to 'CBC'.
hex_key (bool, optional): If the secret key is a hex string. Defaults to False.
hex_iv (bool, optional): If the IV is a hex string. Defaults to True.
Returns:
Chepy: The Chepy object.
Examples:
>>> c = Chepy("5fb8c186394fc399849b89d3b6605fa3")
>>> c.hex_to_str()
>>> c.aes_decrypt("7365637265742070617373776f726421", hex_key=True)
>>> c.o
b"some data"
"""
assert mode in ["CBC", "OFB", "CTR", "ECB", "GCM"], "Not a valid mode."
key, iv = self._convert_key(key, iv, hex_key, hex_iv)
if mode == "CBC":
cipher = AES.new(key, mode=AES.MODE_CBC, iv=iv)
self.state = unpad(cipher.decrypt(self._convert_to_bytes()), 16)
return self
elif mode == "ECB":
cipher = AES.new(key, mode=AES.MODE_ECB)
self.state = unpad(cipher.decrypt(self._convert_to_bytes()), 16)
return self
elif mode == "CTR":
cipher = AES.new(key, mode=AES.MODE_CTR, nonce=b"")
self.state = cipher.decrypt(self._convert_to_bytes())
return self
elif mode == "GCM":
cipher = AES.new(
key,
mode=AES.MODE_GCM,
nonce=binascii.unhexlify("00000000000000000000000000000000"),
)
self.state = cipher.decrypt(self._convert_to_bytes())
return self
elif mode == "OFB":
cipher = AES.new(key, mode=AES.MODE_OFB, iv=iv)
self.state = cipher.decrypt(self._convert_to_bytes())
return self
def decrypt(self, file_path):
block_size = self.read_kb * 1024
data_handle_func = self.cipher.decrypt
# 读取到文件尾部时，执行解密后尾部去除补位
data_end_handle_func = lambda d: unpad(self.cipher.decrypt(d), self.multiple_of_byte)
return ByteCrypto.handle(file_path, block_size, data_handle_func, data_end_handle_func)
privKeyObj = RSA.importKey(binPrivKey)
pubKeyObj = RSA.importKey(binPubKey)
#KRIPTIRAMO PORUKU SIM KLJUCEM
cipher = Sim.new(Simkljuc, SimC)
input = pad(data.read(), 64)
C1 = cipher.encrypt(input)
#JAVNIM KLJUCEM PRIMATELJA KRIPTIRAMO SIMETRICNI KLJUC
cipher = PKCS1_OAEP.new(pubKeyObj)
C2 = cipher.encrypt(Simkljuc)
rj = b64encode(str(C2))
print(rj)
cipher = PKCS1_OAEP.new(privKeyObj)
KljucZaDek = cipher.decrypt(C2)
cipher = Sim.new(KljucZaDek, SimC)
ciphertext = cipher.decrypt(C1)
print(unpad(ciphertext, 64))
with open('digitalnaomotnica.txt', 'w') as f:
f.write('''---BEGIN OS2 CRYPTO DATA---
Description:
Envelope
File name:
datoteka.txt
Method:
{simetricni}
{asimetricni}
Key length:
{sym_key_len}
{asym_key_len}
Envelope data:
{data}
Envelope crypt key:
def request(flow: http.HTTPFlow):
global MSLAESKey
if MSLAESKey is None:
initSession()
if isPathEvaluator(flow.request.pretty_url):
logging.info("Netflix pathEvaluator request: " +
flow.request.pretty_url)
if IS_PYTHON2:
logging.info(
unquote(flow.request.content.decode('utf-8')).decode('utf-8'))
else:
logging.info(unquote(flow.request.content.decode('utf-8')))
if isMSLAPI(flow.request.pretty_url):
logging.info("Netflix msl request: " + flow.request.pretty_url)
parsedRequest = None
parsedReqChunks = []
headerEndOffset = -1
try:
parsedRequest = json.loads(flow.request.content)
except json.JSONDecodeError as e:
headerEndOffset = e.pos
parsedRequest = json.loads(flow.request.content[0:e.pos])
appendChunk(parsedReqChunks, flow.request.content[e.pos:])
#logging.info(flow.request.content.decode())
if not "headerdata" in parsedRequest.keys():
return
headerData = b64decode(parsedRequest["headerdata"])
#logging.info(headerData.decode())
parsedHeaderData = json.loads(headerData)
if "keyrequestdata" in parsedHeaderData.keys():
#logging.info("ProxySignKey: " + b64encode(ProxySignKey.publickey().exportKey("DER")).decode())
#logging.info(flow.request.content.decode())
pubKeyStr = parsedHeaderData["keyrequestdata"][0]["keydata"][
"publickey"]
logging.info("Client pubkey: " + pubKeyStr)
global Mechanism
global ClientPublicKey
global ProxyRSAKey
Mechanism = parsedHeaderData["keyrequestdata"][0]["keydata"][
"mechanism"]
ClientPublicKey = RSA.import_key(b64decode(pubKeyStr))
ProxyRSAKey = RSA.generate(2048)
proxyPubKeyStr = b64encode(
ProxyRSAKey.publickey().exportKey("DER")).decode()
logging.info("To be replaced with: " + proxyPubKeyStr)
parsedHeaderData["keyrequestdata"][0]["keydata"][
"publickey"] = proxyPubKeyStr
parsedRequest["headerdata"] = b64encode(
json.dumps(parsedHeaderData).encode()).decode()
contentRest = b""
if headerEndOffset != -1:
contentRest = flow.request.content[headerEndOffset:]
flow.request.content = json.dumps(
parsedRequest).encode() + contentRest
#logging.info(flow.request.content.decode())
elif "ciphertext" in parsedHeaderData.keys() and MSLAESKey is not None:
iv = b64decode(parsedHeaderData["iv"])
cipher = AES.new(MSLAESKey, AES.MODE_CBC, iv)
cipherText = b64decode(parsedHeaderData["ciphertext"])
try:
plainText = unpad(cipher.decrypt(cipherText), 16)
logging.info(plainText.decode())
except ValueError:
logging.error("Error: incorrect AES key")
#logging.info("Number of chunks: " + str(len(parsedReqChunks)))
for chunk in parsedReqChunks:
if MSLAESKey is None:
continue
payload = json.loads(b64decode(chunk["payload"]))
iv = b64decode(payload["iv"])
cipher = AES.new(MSLAESKey, AES.MODE_CBC, iv)
cipherText = b64decode(payload["ciphertext"])
try:
plainText = unpad(cipher.decrypt(cipherText), 16)
except ValueError:
logging.error("Error: incorrect AES key")
continue
plainJSON = None
try:
plainJSON = json.loads(plainText)
except json.JSONDecodeError as e:
plainJSON = json.loads(plainText[0:e.pos])
#logging.info(plainText.decode())
decoded = b64decode(plainJSON["data"])
if "compressionalgo" in plainJSON.keys():
if plainJSON["compressionalgo"] == "GZIP":
decoded = gzip.decompress(decoded)
elif plainJSON["compressionalgo"] == "LZW":
decoded = lzw_decompress(decoded)
logging.info(decoded.decode())
w_file.close()
try:
aprox_size_mb = round(
os.path.getsize('./task2_128_lt1mb.bin') / 1000000.0, 5)
start_time = time() # Adding a start time to get the difference.
while True:
now = time()
elapsed_time = now - start_time
if not elapsed_time >= total_seconds:
# perform another encryption and decryption if elapsed time is less than 1 second.
number_of_iterations += 1
r_file = open('./task2_128_lt1mb.bin', 'rb')
ciphered_data = r_file.read()
r_file.close()
# Decrypt
cipher = AES.new(aes_key, AES.MODE_CBC, iv)
plaintext = unpad(cipher.decrypt(ciphered_data), AES.block_size)
else:
break
print(
"\n (AES MODE: CBC, KEYSIZE: 128-bit) The max file size that could be decrypted in 1 second on this computer is: "
+ str(number_of_iterations * aprox_size_mb) + "MB")
except ValueError, KeyError:
print("Incorrect decryption")
#key = Random.new().read(AES.block_size)
#key = bytearray.fromhex('6ab9f619a67b90f58d590e466f8b3f33')
key = '1234567890123456'.encode()
#iv = Random.new().read(AES.block_size)
iv = bytearray.fromhex('af7bc4709ae803b616b3b6f161e2b409')
plaintext = 'Huynh Truong Minh Quang'.encode()
enc = encryptCBC(plaintext, key)
dec = decryptCBC(enc, key)
print("Key: ", key.hex())
print("IV: ", iv.hex())
print("Cipher: ", enc.hex())
print("Cipher (base64): ", base64.b64encode(enc))
print("Plain: ", dec.decode())
print(dec.hex())
file = 'input.jpg'
encrypt_file(file, key)
decrypt_file('input.jpg.enc', key)
##decrypt from hex
ciphertext = bytearray.fromhex(
'0bd77995a9e5f022ac46fad44e815d91ce20adaef47eb6563844ea77dc55bf63')
cipher = AES.new(key, AES.MODE_CBC, iv)
plaintext = cipher.decrypt(ciphertext)
plaintext = unpad(plaintext, AES.block_size)
print(plaintext.hex())
print(plaintext.decode())
def decrypt_aes128cbc_buffer_to_str(data, key, iv):
cipher = AES.new(key.encode("ascii"), AES.MODE_CBC, iv.encode("ascii"))
return unpad(cipher.decrypt(data), AES.block_size)
def unpad_aes(data):
try:
return unpad(data, AES.block_size)
except (ValueError):
print('Padding is incorrect')
sys.exit(1)
encryptedMessageEncoded1 = RSA_cipher1.encrypt(
nonEncryptedMessageEncoded1)
print('\nSent ciphertext: "{}" (Step 1)'.format(
encryptedMessageEncoded1))
centralizedCertificateAuthority.sendall(encryptedMessageEncoded1)
# Application server registration; reception and parsing of message contents (2)
# (Centralized Certificate Authority -> Application Server)
# Expected message contents:
# [Application Server Public-Key||Application Server Private-Key +\
# ||Certificate||Application Server ID||Timestamp2]
cipher2 = DES.new(applicationServer_tk.encode('utf-8'), DES.MODE_ECB)
receivedData2 = centralizedCertificateAuthority.recv(4096)
receivedDataDecrypted2 = cipher2.decrypt(
receivedData2) # stores decoded byte data as string
unpad(receivedDataDecrypted2, BLOCK_SIZE)
receivedDataDecryptedDecoded2 = receivedDataDecrypted2.decode(
"utf-8").strip()
print('\nTEST >>> "{}" (Step 2)'.format(receivedDataDecrypted2))
print('\nReceived ciphertext: "{}" (Step 2)'.format(receivedData2))
receivedTimestamp2 = receivedDataDecryptedDecoded2[-10:]
receivedApplicationServerID = receivedDataDecryptedDecoded2[-19:-10]
upperBoundApplicationServerPublicKey = receivedDataDecryptedDecoded2.rindex(
"END PUBLIC KEY-----") + 19
lowerBoundApplicationServerPublicKey = receivedDataDecryptedDecoded2.find(
"-----BEGIN PUBLIC KEY")
receivedApplicationServerPublicKey =\
receivedDataDecryptedDecoded2[lowerBoundApplicationServerPublicKey:upperBoundApplicationServerPublicKey]
upperBoundApplicationServerPrivateKey = receivedDataDecryptedDecoded2.rindex(
"END RSA PRIVATE KEY-----") + 24
lowerBoundApplicationServerPrivateKey = receivedDataDecryptedDecoded2.find(
def test1(self):
padded = pad(b(""), 4, 'iso7816')
self.failUnless(padded == uh(b("80000000")))
back = unpad(padded, 4, 'iso7816')
self.failUnless(back == b(""))
def decrypt(data, passphrase):
"""Decrypt a piece of data using a passphrase and *PBES2*.
The algorithm to use is automatically detected.
:Parameters:
data : byte string
The piece of data to decrypt.
passphrase : byte string
The passphrase to use for decrypting the data.
:Returns:
The decrypted data, as a binary string.
"""
encrypted_private_key_info = decode_der(DerSequence, data)
encryption_algorithm = decode_der(
DerSequence,
encrypted_private_key_info[0]
)
encrypted_data = decode_der(
DerOctetString,
encrypted_private_key_info[1]
).payload
pbe_oid = decode_der(DerObjectId, encryption_algorithm[0]).value
if pbe_oid != "1.2.840.113549.1.5.13":
raise PbesError("Not a PBES2 object")
pbes2_params = decode_der(DerSequence, encryption_algorithm[1])
### Key Derivation Function selection
key_derivation_func = decode_der(DerSequence, pbes2_params[0])
key_derivation_oid = decode_der(
DerObjectId,
key_derivation_func[0]
).value
# We only support PBKDF2 or scrypt
if key_derivation_oid == "1.2.840.113549.1.5.12":
pbkdf2_params = decode_der(DerSequence, key_derivation_func[1])
salt = decode_der(DerOctetString, pbkdf2_params[0]).payload
iteration_count = pbkdf2_params[1]
if len(pbkdf2_params) > 2:
kdf_key_length = pbkdf2_params[2]
else:
kdf_key_length = None
if len(pbkdf2_params) > 3:
raise PbesError("Unsupported PRF for PBKDF2")
elif key_derivation_oid == "1.3.6.1.4.1.11591.4.11":
scrypt_params = decode_der(DerSequence, key_derivation_func[1])
salt = decode_der(DerOctetString, scrypt_params[0]).payload
iteration_count, scrypt_r, scrypt_p = [scrypt_params[x]
for x in (1, 2, 3)]
if len(scrypt_params) > 4:
kdf_key_length = scrypt_params[4]
else:
kdf_key_length = None
else:
raise PbesError("Unsupported PBES2 KDF")
### Cipher selection
encryption_scheme = decode_der(DerSequence, pbes2_params[1])
encryption_oid = decode_der(
DerObjectId,
encryption_scheme[0]
).value
if encryption_oid == "1.2.840.113549.3.7":
# DES_EDE3_CBC
ciphermod = DES3
key_size = 24
elif encryption_oid == "2.16.840.1.101.3.4.1.2":
# AES128_CBC
ciphermod = AES
key_size = 16
elif encryption_oid == "2.16.840.1.101.3.4.1.22":
# AES192_CBC
ciphermod = AES
key_size = 24
elif encryption_oid == "2.16.840.1.101.3.4.1.42":
# AES256_CBC
ciphermod = AES
key_size = 32
else:
raise PbesError("Unsupported PBES2 cipher")
if kdf_key_length and kdf_key_length != key_size:
raise PbesError("Mismatch between PBES2 KDF parameters"
" and selected cipher")
IV = decode_der(DerOctetString, encryption_scheme[1]).payload
# Create cipher
if key_derivation_oid == "1.2.840.113549.1.5.12": # PBKDF2
key = PBKDF2(passphrase, salt, key_size, iteration_count)
else:
key = scrypt(passphrase, salt, key_size, iteration_count,
scrypt_r, scrypt_p)
cipher = ciphermod.new(key, ciphermod.MODE_CBC, IV)
# Decrypt data
pt = cipher.decrypt(encrypted_data)
return unpad(pt, cipher.block_size)
def test4(self):
padded = pad(uh(b("1234567890")), 4, 'iso7816')
self.failUnless(padded == uh(b("1234567890800000")))
back = unpad(padded, 4, 'iso7816')
self.failUnless(back == uh(b("1234567890")))
def test3(self):
padded = pad(uh(b("123456")), 4, 'iso7816')
self.assertTrue(padded == uh(b("12345680")))
#import pdb; pdb.set_trace()
back = unpad(padded, 4, 'iso7816')
self.assertTrue(back == uh(b("123456")))
def test3(self):
padded = pad(uh(b("123456")), 4)
self.failUnless(padded == uh(b("12345601")))
back = unpad(padded, 4)
self.failUnless(back == uh(b("123456")))
def test3(self):
padded = pad(uh(b("123456")), 4, 'iso7816')
self.failUnless(padded == uh(b("12345680")))
#import pdb; pdb.set_trace()
back = unpad(padded, 4, 'iso7816')
self.failUnless(back == uh(b("123456")))
def decrypt(self, data_to_decrypt):
self.cipher = self.gen_cipher()
return unpad(self.cipher.decrypt(data_to_decrypt), AES.block_size)
def test2(self):
padded = pad(uh(b("12345678")), 4, 'x923')
self.assertTrue(padded == uh(b("1234567800000004")))
back = unpad(padded, 4, 'x923')
self.assertTrue(back == uh(b("12345678")))
print('Bind failed. Error Code : ' + str(msg[0]) + ' Message ' + msg[1])
sys.exit()
print('Socket bind complete')
s.listen(10)
print('Socket now listening')
#wait to accept a connection - blocking call
while 1:
conn, addr = s.accept()
print('A new padding test requested by ' + addr[0] + ':' + str(addr[1]))
iv = conn.recv(AES.block_size)
ciphertext = conn.recv(1024)
cipher = AES.new(key, AES.MODE_CBC, iv)
try:
unpad(cipher.decrypt(ciphertext), AES.block_size)
#PKCS 01 / 0202 / 030303
except ValueError:
conn.send(b'NO')
continue
conn.send(b'OK')
conn.close()
s.close()
def test4(self):
padded = pad(uh(b("1234567890")), 4, 'iso7816')
self.failUnless(padded == uh(b("1234567890800000")))
back = unpad(padded, 4, 'iso7816')
self.failUnless(back == uh(b("1234567890")))
def test1(self):
padded = pad(b(""), 4, 'iso7816')
self.assertTrue(padded == uh(b("80000000")))
back = unpad(padded, 4, 'iso7816')
self.assertTrue(back == b(""))
cipher = DES.new(key, DES.MODE_CTR)
# Ciframos, haciendo que data sea multiplo del tamaño de bloque
ciphertext = cipher.encrypt(pad(data, BLOCK_SIZE_DES))
# Mostramos el cifrado por pantalla en modo binario y en modo base 64
print(ciphertext)
encoded_ciphertext = base64.b64encode(ciphertext)
print(encoded_ciphertext)
# Creamos un mecanismo de (des)cifrado DES en modo CBC con una inicializacion IV
# Ambos, cifrado y descifrado, se crean de la misma forma
decipher_des = DES.new(key, DES.MODE_CTR, IV)
# Desciframos, eliminamos el padding, y recuperamos la cadena
new_data = unpad(decipher_des.decrypt(ciphertext),
BLOCK_SIZE_DES).decode("utf-8", "ignore")
# Imprimimos los datos descifrados
print(new_data)
class DES_CIPHER:
BLOCK_SIZE_DES = 8 # DES: Bloque de 64 bits
def __init__(self, key):
#Inicializa las variables locales
self.key = key
def cifrar(self, cadena, IV):
#Cifra el parámetro cadena (de tipo String) con una IV específica, y devuelve el texto cifrado binario
def test4(self):
padded = pad(uh(b("1234567890")), 4, 'iso7816')
self.assertTrue(padded == uh(b("1234567890800000")))
back = unpad(padded, 4, 'iso7816')
self.assertTrue(back == uh(b("1234567890")))
def descifrar(self, cifrado, IV):
#Descrifra el parámetro cifrado (de tipo binario) con una IV específica, y devuelve la cadena en claro de tipo String
decipher_des = DES.new(self.key, DES.MODE_CTR, IV)
new_data = unpad(decipher_des.decrypt(cifrado),
self.BLOCK_SIZE_DES).decode("utf-8", "ignore")
return new_data
def test1(self):
padded = pad(b(""), 4, 'x923')
self.assertTrue(padded == uh(b("00000004")))
back = unpad(padded, 4, 'x923')
self.assertTrue(back == b(""))
def decrypt(data, key):
payload = base64.b64decode(data)
data = aes_decrypt(payload, key)
# response starts with 2 random bytes, exclude them
response = unpad(data, 16, style='pkcs7')[2:]
return response.decode('ascii')
def test3(self):
padded = pad(uh(b("123456")), 4, 'x923')
self.assertTrue(padded == uh(b("12345601")))
back = unpad(padded, 4, 'x923')
self.assertTrue(back == uh(b("123456")))
def decrypt_confirmation_ecb(encrypted_text):
cipher = AES.new(K1, AES.MODE_ECB) # Setup cipher
original_data = unpad(cipher.decrypt(encrypted_text), AES.block_size)
return original_data
def decrypt(self, encrypt_string):
encrypt_byte_string = base64.urlsafe_b64decode(bytes(map(ord, encrypt_string)))
pad_byte_string = self.cipher.decrypt(encrypt_byte_string)
string = unpad(pad_byte_string, MULTIPLE_OF_BYTE).decode('utf-8')
return string
print("Sua chave é inválida")
else:
if modo == "C":
chave = bytes.fromhex(chave)
# Cria a cifra AES, utilizando a chave informada e com o modo ECB, que é o mais simples
cifra = AES.new(chave, AES.MODE_ECB)
texto = bytes.fromhex(texto)
# Realiza a encriptação dos dados e adiciona padding caso necessário
resultado = cifra.encrypt(pad(texto, AES.block_size))
# Mostrando o resultado da cifra em hexadecimal
print(hex(int.from_bytes(resultado, byteorder='big'))[2:])
elif modo == "D":
chave = bytes.fromhex(chave)
# Cria a cifra AES, utilizando a chave informada e com o modo ECB, que é o mais simples
cifra = AES.new(chave, AES.MODE_ECB)
texto = bytes.fromhex(texto)
# Realiza a encriptação dos dados e remove padding caso necessário
resultado = unpad(cifra.decrypt(texto), AES.block_size)
# Mostrando o resultado da decifragem em hexadecimal
print(hex(int.from_bytes(resultado, byteorder='big'))[2:])
else:
print("O modo informado não existe")
else:
print("A sua entrada está incorreta, digite \"ajuda\" caso queira saber mais")
input()
def decode(pem_data, passphrase=None):
"""Decode a PEM block into binary.
Args:
pem_data (string):
The PEM block.
passphrase (byte string):
If given and the PEM block is encrypted,
the key will be derived from the passphrase.
Returns:
A tuple with the binary data, the marker string, and a boolean to
indicate if decryption was performed.
Raises:
ValueError: if decoding fails, if the PEM file is encrypted and no passphrase has
been provided or if the passphrase is incorrect.
"""
# Verify Pre-Encapsulation Boundary
r = re.compile(r"\s*-----BEGIN (.*)-----\s+")
m = r.match(pem_data)
if not m:
raise ValueError("Not a valid PEM pre boundary")
marker = m.group(1)
# Verify Post-Encapsulation Boundary
r = re.compile(r"-----END (.*)-----\s*$")
m = r.search(pem_data)
if not m or m.group(1) != marker:
raise ValueError("Not a valid PEM post boundary")
# Removes spaces and slit on lines
lines = pem_data.replace(" ", '').split()
# Decrypts, if necessary
if lines[1].startswith('Proc-Type:4,ENCRYPTED'):
if not passphrase:
raise ValueError("PEM is encrypted, but no passphrase available")
DEK = lines[2].split(':')
if len(DEK) != 2 or DEK[0] != 'DEK-Info':
raise ValueError("PEM encryption format not supported.")
algo, salt = DEK[1].split(',')
salt = unhexlify(tobytes(salt))
padding = True
if algo == "DES-CBC":
key = _EVP_BytesToKey(passphrase, salt, 8)
objdec = DES.new(key, DES.MODE_CBC, salt)
elif algo == "DES-EDE3-CBC":
key = _EVP_BytesToKey(passphrase, salt, 24)
objdec = DES3.new(key, DES3.MODE_CBC, salt)
elif algo == "AES-128-CBC":
key = _EVP_BytesToKey(passphrase, salt[:8], 16)
objdec = AES.new(key, AES.MODE_CBC, salt)
elif algo == "AES-192-CBC":
key = _EVP_BytesToKey(passphrase, salt[:8], 24)
objdec = AES.new(key, AES.MODE_CBC, salt)
elif algo == "AES-256-CBC":
key = _EVP_BytesToKey(passphrase, salt[:8], 32)
objdec = AES.new(key, AES.MODE_CBC, salt)
elif algo.lower() == "id-aes256-gcm":
key = _EVP_BytesToKey(passphrase, salt[:8], 32)
objdec = AES.new(key, AES.MODE_GCM, nonce=salt)
padding = False
else:
raise ValueError("Unsupport PEM encryption algorithm (%s)." % algo)
lines = lines[2:]
else:
objdec = None
# Decode body
data = a2b_base64(''.join(lines[1:-1]))
enc_flag = False
if objdec:
if padding:
data = unpad(objdec.decrypt(data), objdec.block_size)
else:
# There is no tag, so we don't use decrypt_and_verify
data = objdec.decrypt(data)
enc_flag = True
return (data, marker, enc_flag)
"""CAPTURO EL MENSAJE EN EL DISCO DURO"""
archivo = "mensaje.docx"
escribearchivo = open(archivo,"rb")
mensajecapturado = escribearchivo.read()
escribearchivo.close()
#Ahora que tengo el mensaje como conozco la clave de b con el servidor descifro el mensaje
msg_b_t = bytearray.fromhex(mensajecapturado.decode("UTF-8"))
# B descifra los datos a través de la clave KBT, guarda la clave KAB y la identidad
# de Alicia y crea un valor random denominado Rb
uncipher_b_t = AES.new(key_b_t, AES.MODE_ECB)
json_b_t = unpad(uncipher_b_t.decrypt(msg_b_t), BLOCK_SIZE_AES).decode("UTF-8", "ignore")
msg_a_b = json.loads(json_b_t)
a_k_ab, b_alice = msg_a_b
t_k_ab = bytearray.fromhex(a_k_ab)
key_a_t=t_k_ab
#####################################################################
# COMPLETAR: CONTACTAR CON BOB, SEGUIR EL PROTOCOLO NEEDHAM-SCHROEDER
#####################################################################
# Crea el socket servidor y escucha
def decode(pem_data, passphrase=None):
"""Decode a PEM block into binary.
:Parameters:
pem_data : string
The PEM block.
passphrase : byte string
If given and the PEM block is encrypted,
the key will be derived from the passphrase.
:Returns:
A tuple with the binary data, the marker string, and a boolean to
indicate if decryption was performed.
:Raises ValueError:
If decoding fails, if the PEM file is encrypted and no passphrase has
been provided or if the passphrase is incorrect.
"""
# Verify Pre-Encapsulation Boundary
r = re.compile("\s*-----BEGIN (.*)-----\n")
m = r.match(pem_data)
if not m:
raise ValueError("Not a valid PEM pre boundary")
marker = m.group(1)
# Verify Post-Encapsulation Boundary
r = re.compile("-----END (.*)-----\s*$")
m = r.search(pem_data)
if not m or m.group(1) != marker:
raise ValueError("Not a valid PEM post boundary")
# Removes spaces and slit on lines
lines = pem_data.replace(" ", '').split()
# Decrypts, if necessary
if lines[1].startswith('Proc-Type:4,ENCRYPTED'):
if not passphrase:
raise ValueError("PEM is encrypted, but no passphrase available")
DEK = lines[2].split(':')
if len(DEK) != 2 or DEK[0] != 'DEK-Info':
raise ValueError("PEM encryption format not supported.")
algo, salt = DEK[1].split(',')
salt = unhexlify(tobytes(salt))
if algo == "DES-CBC":
# This is EVP_BytesToKey in OpenSSL
key = PBKDF1(passphrase, salt, 8, 1, MD5)
objdec = DES.new(key, DES.MODE_CBC, salt)
elif algo == "DES-EDE3-CBC":
# Note that EVP_BytesToKey is note exactly the same as PBKDF1
key = PBKDF1(passphrase, salt, 16, 1, MD5)
key += PBKDF1(key + passphrase, salt, 8, 1, MD5)
objdec = DES3.new(key, DES3.MODE_CBC, salt)
elif algo == "AES-128-CBC":
key = PBKDF1(passphrase, salt[:8], 16, 1, MD5)
objdec = AES.new(key, AES.MODE_CBC, salt)
else:
raise ValueError("Unsupport PEM encryption algorithm.")
lines = lines[2:]
else:
objdec = None
# Decode body
data = a2b_base64(b(''.join(lines[1:-1])))
enc_flag = False
if objdec:
data = unpad(objdec.decrypt(data), objdec.block_size)
enc_flag = True
return (data, marker, enc_flag)
def decrypt(data, passphrase):
"""Decrypt a piece of data using a passphrase and *PBES2*.
The algorithm to use is automatically detected.
:Parameters:
data : byte string
The piece of data to decrypt.
passphrase : byte string
The passphrase to use for decrypting the data.
:Returns:
The decrypted data, as a binary string.
"""
enc_private_key_info = DerSequence().decode(data, nr_elements=2)
enc_algo = DerSequence().decode(enc_private_key_info[0])
encrypted_data = DerOctetString().decode(enc_private_key_info[1]).payload
pbe_oid = DerObjectId().decode(enc_algo[0]).value
if pbe_oid != _OID_PBES2:
raise PbesError("Not a PBES2 object")
pbes2_params = DerSequence().decode(enc_algo[1], nr_elements=2)
### Key Derivation Function selection
kdf_info = DerSequence().decode(pbes2_params[0], nr_elements=2)
kdf_oid = DerObjectId().decode(kdf_info[0]).value
kdf_key_length = None
# We only support PBKDF2 or scrypt
if kdf_oid == _OID_PBKDF2:
pbkdf2_params = DerSequence().decode(kdf_info[1], nr_elements=(2, 3, 4))
salt = DerOctetString().decode(pbkdf2_params[0]).payload
iteration_count = pbkdf2_params[1]
left = len(pbkdf2_params) - 2
idx = 2
if left > 0:
try:
kdf_key_length = pbkdf2_params[idx] - 0
left -= 1
idx += 1
except TypeError:
pass
# Default is HMAC-SHA1
pbkdf2_prf_oid = "1.2.840.113549.2.7"
if left > 0:
pbkdf2_prf_algo_id = DerSequence().decode(pbkdf2_params[idx])
pbkdf2_prf_oid = DerObjectId().decode(pbkdf2_prf_algo_id[0]).value
elif kdf_oid == _OID_SCRYPT:
scrypt_params = DerSequence().decode(kdf_info[1], nr_elements=(4, 5))
salt = DerOctetString().decode(scrypt_params[0]).payload
iteration_count, scrypt_r, scrypt_p = [scrypt_params[x]
for x in (1, 2, 3)]
if len(scrypt_params) > 4:
kdf_key_length = scrypt_params[4]
else:
kdf_key_length = None
else:
raise PbesError("Unsupported PBES2 KDF")
### Cipher selection
enc_info = DerSequence().decode(pbes2_params[1])
enc_oid = DerObjectId().decode(enc_info[0]).value
if enc_oid == _OID_DES_EDE3_CBC:
# DES_EDE3_CBC
ciphermod = DES3
key_size = 24
elif enc_oid == _OID_AES128_CBC:
# AES128_CBC
ciphermod = AES
key_size = 16
elif enc_oid == _OID_AES192_CBC:
# AES192_CBC
ciphermod = AES
key_size = 24
elif enc_oid == _OID_AES256_CBC:
# AES256_CBC
ciphermod = AES
key_size = 32
else:
raise PbesError("Unsupported PBES2 cipher")
if kdf_key_length and kdf_key_length != key_size:
raise PbesError("Mismatch between PBES2 KDF parameters"
" and selected cipher")
IV = DerOctetString().decode(enc_info[1]).payload
# Create cipher
if kdf_oid == _OID_PBKDF2:
if pbkdf2_prf_oid == _OID_HMAC_SHA1:
hmac_hash_module = SHA1
elif pbkdf2_prf_oid == _OID_HMAC_SHA224:
hmac_hash_module = SHA224
elif pbkdf2_prf_oid == _OID_HMAC_SHA256:
hmac_hash_module = SHA256
elif pbkdf2_prf_oid == _OID_HMAC_SHA384:
hmac_hash_module = SHA384
elif pbkdf2_prf_oid == _OID_HMAC_SHA512:
hmac_hash_module = SHA512
else:
raise PbesError("Unsupported HMAC %s" % pbkdf2_prf_oid)
key = PBKDF2(passphrase, salt, key_size, iteration_count,
hmac_hash_module=hmac_hash_module)
else:
key = scrypt(passphrase, salt, key_size, iteration_count,
scrypt_r, scrypt_p)
cipher = ciphermod.new(key, ciphermod.MODE_CBC, IV)
# Decrypt data
pt = cipher.decrypt(encrypted_data)
return unpad(pt, cipher.block_size)
