Implement new default cipher class AES256

This commit is contained in:
James Tanner 2014-03-10 16:15:44 -05:00 committed by James Cammarata
parent ba0fec4f42
commit 0d6f6ad282
6 changed files with 410 additions and 51 deletions

View file

@ -52,7 +52,7 @@ def build_option_parser(action):
sys.exit()
# options for all actions
#parser.add_option('-c', '--cipher', dest='cipher', default="AES", help="cipher to use")
#parser.add_option('-c', '--cipher', dest='cipher', default="AES256", help="cipher to use")
parser.add_option('--debug', dest='debug', action="store_true", help="debug")
parser.add_option('--vault-password-file', dest='password_file',
help="vault password file")
@ -119,7 +119,7 @@ def execute_create(args, options, parser):
else:
password = _read_password(options.password_file)
cipher = 'AES'
cipher = 'AES256'
if hasattr(options, 'cipher'):
cipher = options.cipher
@ -133,7 +133,7 @@ def execute_decrypt(args, options, parser):
else:
password = _read_password(options.password_file)
cipher = 'AES'
cipher = 'AES256'
if hasattr(options, 'cipher'):
cipher = options.cipher
@ -169,7 +169,7 @@ def execute_encrypt(args, options, parser):
else:
password = _read_password(options.password_file)
cipher = 'AES'
cipher = 'AES256'
if hasattr(options, 'cipher'):
cipher = options.cipher

View file

@ -30,6 +30,22 @@ from binascii import hexlify
from binascii import unhexlify
from ansible import constants as C
from Crypto.Hash import SHA256, HMAC
# Counter import fails for 2.0.1, requires >= 2.6.1 from pip
try:
from Crypto.Util import Counter
HAS_COUNTER = True
except ImportError:
HAS_COUNTER = False
# KDF import fails for 2.0.1, requires >= 2.6.1 from pip
try:
from Crypto.Protocol.KDF import PBKDF2
HAS_PBKDF2 = True
except ImportError:
HAS_PBKDF2 = False
# AES IMPORTS
try:
from Crypto.Cipher import AES as AES
@ -37,15 +53,17 @@ try:
except ImportError:
HAS_AES = False
CRYPTO_UPGRADE = "ansible-vault requires a newer version of pycrypto than the one installed on your platform. You may fix this with OS-specific commands such as: rpm -e --nodeps python-crypto; pip install pycrypto"
HEADER='$ANSIBLE_VAULT'
CIPHER_WHITELIST=['AES']
CIPHER_WHITELIST=['AES', 'AES256']
class VaultLib(object):
def __init__(self, password):
self.password = password
self.cipher_name = None
self.version = '1.0'
self.version = '1.1'
def is_encrypted(self, data):
if data.startswith(HEADER):
@ -59,7 +77,8 @@ class VaultLib(object):
raise errors.AnsibleError("data is already encrypted")
if not self.cipher_name:
raise errors.AnsibleError("the cipher must be set before encrypting data")
self.cipher_name = "AES256"
#raise errors.AnsibleError("the cipher must be set before encrypting data")
if 'Vault' + self.cipher_name in globals() and self.cipher_name in CIPHER_WHITELIST:
cipher = globals()['Vault' + self.cipher_name]
@ -67,13 +86,17 @@ class VaultLib(object):
else:
raise errors.AnsibleError("%s cipher could not be found" % self.cipher_name)
"""
# combine sha + data
this_sha = sha256(data).hexdigest()
tmp_data = this_sha + "\n" + data
"""
# encrypt sha + data
tmp_data = this_cipher.encrypt(tmp_data, self.password)
enc_data = this_cipher.encrypt(data, self.password)
# add header
tmp_data = self._add_headers_and_hexify_encrypted_data(tmp_data)
tmp_data = self._add_header(enc_data)
return tmp_data
def decrypt(self, data):
@ -83,8 +106,9 @@ class VaultLib(object):
if not self.is_encrypted(data):
raise errors.AnsibleError("data is not encrypted")
# clean out header, hex and sha
data = self._split_headers_and_get_unhexified_data(data)
# clean out header
data = self._split_header(data)
# create the cipher object
if 'Vault' + self.cipher_name in globals() and self.cipher_name in CIPHER_WHITELIST:
@ -96,33 +120,26 @@ class VaultLib(object):
# try to unencrypt data
data = this_cipher.decrypt(data, self.password)
# split out sha and verify decryption
split_data = data.split("\n")
this_sha = split_data[0]
this_data = '\n'.join(split_data[1:])
test_sha = sha256(this_data).hexdigest()
if this_sha != test_sha:
raise errors.AnsibleError("Decryption failed")
return data
return this_data
def _add_header(self, data):
# combine header and encrypted data in 80 char columns
def _add_headers_and_hexify_encrypted_data(self, data):
# combine header and hexlified encrypted data in 80 char columns
tmpdata = hexlify(data)
tmpdata = [tmpdata[i:i+80] for i in range(0, len(tmpdata), 80)]
#tmpdata = hexlify(data)
tmpdata = [data[i:i+80] for i in range(0, len(data), 80)]
if not self.cipher_name:
raise errors.AnsibleError("the cipher must be set before adding a header")
dirty_data = HEADER + ";" + str(self.version) + ";" + self.cipher_name + "\n"
for l in tmpdata:
dirty_data += l + '\n'
return dirty_data
def _split_headers_and_get_unhexified_data(self, data):
def _split_header(self, data):
# used by decrypt
tmpdata = data.split('\n')
@ -130,14 +147,22 @@ class VaultLib(object):
self.version = str(tmpheader[1].strip())
self.cipher_name = str(tmpheader[2].strip())
clean_data = ''.join(tmpdata[1:])
clean_data = '\n'.join(tmpdata[1:])
"""
# strip out newline, join, unhex
clean_data = [ x.strip() for x in clean_data ]
clean_data = unhexlify(''.join(clean_data))
"""
return clean_data
def __enter__(self):
return self
def __exit__(self, *err):
pass
class VaultEditor(object):
# uses helper methods for write_file(self, filename, data)
# to write a file so that code isn't duplicated for simple
@ -153,6 +178,9 @@ class VaultEditor(object):
def create_file(self):
""" create a new encrypted file """
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise errors.AnsibleError(CRYPTO_UPGRADE)
if os.path.isfile(self.filename):
raise errors.AnsibleError("%s exists, please use 'edit' instead" % self.filename)
@ -166,6 +194,10 @@ class VaultEditor(object):
self.write_data(enc_data, self.filename)
def decrypt_file(self):
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise errors.AnsibleError(CRYPTO_UPGRADE)
if not os.path.isfile(self.filename):
raise errors.AnsibleError("%s does not exist" % self.filename)
@ -179,6 +211,9 @@ class VaultEditor(object):
def edit_file(self):
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise errors.AnsibleError(CRYPTO_UPGRADE)
# decrypt to tmpfile
tmpdata = self.read_data(self.filename)
this_vault = VaultLib(self.password)
@ -191,9 +226,11 @@ class VaultEditor(object):
call([EDITOR, tmp_path])
new_data = self.read_data(tmp_path)
# create new vault and set cipher to old
# create new vault
new_vault = VaultLib(self.password)
new_vault.cipher_name = this_vault.cipher_name
# we want the cipher to default to AES256
#new_vault.cipher_name = this_vault.cipher_name
# encrypt new data a write out to tmp
enc_data = new_vault.encrypt(new_data)
@ -203,6 +240,10 @@ class VaultEditor(object):
self.shuffle_files(tmp_path, self.filename)
def encrypt_file(self):
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise errors.AnsibleError(CRYPTO_UPGRADE)
if not os.path.isfile(self.filename):
raise errors.AnsibleError("%s does not exist" % self.filename)
@ -216,14 +257,20 @@ class VaultEditor(object):
raise errors.AnsibleError("%s is already encrypted" % self.filename)
def rekey_file(self, new_password):
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise errors.AnsibleError(CRYPTO_UPGRADE)
# decrypt
tmpdata = self.read_data(self.filename)
this_vault = VaultLib(self.password)
dec_data = this_vault.decrypt(tmpdata)
# create new vault, set cipher to old and password to new
# create new vault
new_vault = VaultLib(new_password)
new_vault.cipher_name = this_vault.cipher_name
# we want to force cipher to the default
#new_vault.cipher_name = this_vault.cipher_name
# re-encrypt data and re-write file
enc_data = new_vault.encrypt(dec_data)
@ -254,11 +301,14 @@ class VaultEditor(object):
class VaultAES(object):
# this version has been obsoleted by the VaultAES256 class
# which uses encrypt-then-mac (fixing order) and also improving the KDF used
# code remains for upgrade purposes only
# http://stackoverflow.com/a/16761459
def __init__(self):
if not HAS_AES:
raise errors.AnsibleError("pycrypto is not installed. Fix this with your package manager, for instance, yum-install python-crypto OR (apt equivalent)")
raise errors.AnsibleError(CRYPTO_UPGRADE)
def aes_derive_key_and_iv(self, password, salt, key_length, iv_length):
@ -278,7 +328,12 @@ class VaultAES(object):
""" Read plaintext data from in_file and write encrypted to out_file """
in_file = BytesIO(data)
# combine sha + data
this_sha = sha256(data).hexdigest()
tmp_data = this_sha + "\n" + data
in_file = BytesIO(tmp_data)
in_file.seek(0)
out_file = BytesIO()
@ -301,14 +356,21 @@ class VaultAES(object):
out_file.write(cipher.encrypt(chunk))
out_file.seek(0)
return out_file.read()
enc_data = out_file.read()
tmp_data = hexlify(enc_data)
return tmp_data
def decrypt(self, data, password, key_length=32):
""" Read encrypted data from in_file and write decrypted to out_file """
# http://stackoverflow.com/a/14989032
data = ''.join(data.split('\n'))
data = unhexlify(data)
in_file = BytesIO(data)
in_file.seek(0)
out_file = BytesIO()
@ -330,6 +392,129 @@ class VaultAES(object):
# reset the stream pointer to the beginning
out_file.seek(0)
return out_file.read()
new_data = out_file.read()
# split out sha and verify decryption
split_data = new_data.split("\n")
this_sha = split_data[0]
this_data = '\n'.join(split_data[1:])
test_sha = sha256(this_data).hexdigest()
if this_sha != test_sha:
raise errors.AnsibleError("Decryption failed")
#return out_file.read()
return this_data
class VaultAES256(object):
"""
Vault implementation using AES-CTR with an HMAC-SHA256 authentication code.
Keys are derived using PBKDF2
"""
# http://www.daemonology.net/blog/2009-06-11-cryptographic-right-answers.html
def gen_key_initctr(self, password, salt):
# 16 for AES 128, 32 for AES256
keylength = 32
# match the size used for counter.new to avoid extra work
ivlength = 16
hash_function = SHA256
# make two keys and one iv
pbkdf2_prf = lambda p, s: HMAC.new(p, s, hash_function).digest()
if not HAS_PBKDF2:
raise errors.AnsibleError(CRYPTO_UPGRADE)
derivedkey = PBKDF2(password, salt, dkLen=(2 * keylength) + ivlength,
count=10000, prf=pbkdf2_prf)
#import epdb; epdb.st()
key1 = derivedkey[:keylength]
key2 = derivedkey[keylength:(keylength * 2)]
iv = derivedkey[(keylength * 2):(keylength * 2) + ivlength]
return key1, key2, hexlify(iv)
def encrypt(self, data, password):
salt = os.urandom(32)
key1, key2, iv = self.gen_key_initctr(password, salt)
# PKCS#7 PAD DATA http://tools.ietf.org/html/rfc5652#section-6.3
bs = AES.block_size
padding_length = (bs - len(data) % bs) or bs
data += padding_length * chr(padding_length)
# COUNTER.new PARAMETERS
# 1) nbits (integer) - Length of the counter, in bits.
# 2) initial_value (integer) - initial value of the counter. "iv" from gen_key_initctr
if not HAS_COUNTER:
raise errors.AnsibleError(CRYPTO_UPGRADE)
ctr = Counter.new(128, initial_value=long(iv, 16))
# AES.new PARAMETERS
# 1) AES key, must be either 16, 24, or 32 bytes long -- "key" from gen_key_initctr
# 2) MODE_CTR, is the recommended mode
# 3) counter=<CounterObject>
cipher = AES.new(key1, AES.MODE_CTR, counter=ctr)
# ENCRYPT PADDED DATA
cryptedData = cipher.encrypt(data)
# COMBINE SALT, DIGEST AND DATA
hmac = HMAC.new(key2, cryptedData, SHA256)
message = "%s\n%s\n%s" % ( hexlify(salt), hmac.hexdigest(), hexlify(cryptedData) )
message = hexlify(message)
return message
def decrypt(self, data, password):
# SPLIT SALT, DIGEST, AND DATA
data = ''.join(data.split("\n"))
data = unhexlify(data)
salt, cryptedHmac, cryptedData = data.split("\n", 2)
salt = unhexlify(salt)
cryptedData = unhexlify(cryptedData)
key1, key2, iv = self.gen_key_initctr(password, salt)
# EXIT EARLY IF DIGEST DOESN'T MATCH
hmacDecrypt = HMAC.new(key2, cryptedData, SHA256)
if not self.is_equal(cryptedHmac, hmacDecrypt.hexdigest()):
return None
# SET THE COUNTER AND THE CIPHER
if not HAS_COUNTER:
raise errors.AnsibleError(CRYPTO_UPGRADE)
ctr = Counter.new(128, initial_value=long(iv, 16))
cipher = AES.new(key1, AES.MODE_CTR, counter=ctr)
# DECRYPT PADDED DATA
decryptedData = cipher.decrypt(cryptedData)
# UNPAD DATA
padding_length = ord(decryptedData[-1])
decryptedData = decryptedData[:-padding_length]
return decryptedData
def is_equal(self, a, b):
# http://codahale.com/a-lesson-in-timing-attacks/
if len(a) != len(b):
return False
result = 0
for x, y in zip(a, b):
result |= ord(x) ^ ord(y)
return result == 0

View file

@ -12,6 +12,21 @@ from nose.plugins.skip import SkipTest
from ansible import errors
from ansible.utils.vault import VaultLib
# Counter import fails for 2.0.1, requires >= 2.6.1 from pip
try:
from Crypto.Util import Counter
HAS_COUNTER = True
except ImportError:
HAS_COUNTER = False
# KDF import fails for 2.0.1, requires >= 2.6.1 from pip
try:
from Crypto.Protocol.KDF import PBKDF2
HAS_PBKDF2 = True
except ImportError:
HAS_PBKDF2 = False
# AES IMPORTS
try:
from Crypto.Cipher import AES as AES
@ -26,8 +41,8 @@ class TestVaultLib(TestCase):
slots = ['is_encrypted',
'encrypt',
'decrypt',
'_add_headers_and_hexify_encrypted_data',
'_split_headers_and_get_unhexified_data',]
'_add_header',
'_split_header',]
for slot in slots:
assert hasattr(v, slot), "VaultLib is missing the %s method" % slot
@ -41,8 +56,7 @@ class TestVaultLib(TestCase):
v = VaultLib('ansible')
v.cipher_name = "TEST"
sensitive_data = "ansible"
sensitive_hex = hexlify(sensitive_data)
data = v._add_headers_and_hexify_encrypted_data(sensitive_data)
data = v._add_header(sensitive_data)
lines = data.split('\n')
assert len(lines) > 1, "failed to properly add header"
header = lines[0]
@ -52,19 +66,18 @@ class TestVaultLib(TestCase):
assert header_parts[0] == '$ANSIBLE_VAULT', "header does not start with $ANSIBLE_VAULT"
assert header_parts[1] == v.version, "header version is incorrect"
assert header_parts[2] == 'TEST', "header does end with cipher name"
assert lines[1] == sensitive_hex
def test_remove_header(self):
def test_split_header(self):
v = VaultLib('ansible')
data = "$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify("ansible")
rdata = v._split_headers_and_get_unhexified_data(data)
data = "$ANSIBLE_VAULT;9.9;TEST\nansible"
rdata = v._split_header(data)
lines = rdata.split('\n')
assert lines[0] == "ansible"
assert v.cipher_name == 'TEST', "cipher name was not set"
assert v.version == "9.9"
def test_encyrpt_decrypt(self):
if not HAS_AES:
def test_encrypt_decrypt_aes(self):
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise SkipTest
v = VaultLib('ansible')
v.cipher_name = 'AES'
@ -73,8 +86,18 @@ class TestVaultLib(TestCase):
assert enc_data != "foobar", "encryption failed"
assert dec_data == "foobar", "decryption failed"
def test_encrypt_decrypt_aes256(self):
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise SkipTest
v = VaultLib('ansible')
v.cipher_name = 'AES256'
enc_data = v.encrypt("foobar")
dec_data = v.decrypt(enc_data)
assert enc_data != "foobar", "encryption failed"
assert dec_data == "foobar", "decryption failed"
def test_encrypt_encrypted(self):
if not HAS_AES:
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise SkipTest
v = VaultLib('ansible')
v.cipher_name = 'AES'
@ -87,7 +110,7 @@ class TestVaultLib(TestCase):
assert error_hit, "No error was thrown when trying to encrypt data with a header"
def test_decrypt_decrypted(self):
if not HAS_AES:
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise SkipTest
v = VaultLib('ansible')
data = "ansible"
@ -99,7 +122,8 @@ class TestVaultLib(TestCase):
assert error_hit, "No error was thrown when trying to decrypt data without a header"
def test_cipher_not_set(self):
if not HAS_AES:
# not setting the cipher should default to AES256
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise SkipTest
v = VaultLib('ansible')
data = "ansible"
@ -108,6 +132,5 @@ class TestVaultLib(TestCase):
enc_data = v.encrypt(data)
except errors.AnsibleError, e:
error_hit = True
assert error_hit, "No error was thrown when trying to encrypt data without the cipher set"
assert not error_hit, "An error was thrown when trying to encrypt data without the cipher set"
assert v.cipher_name == "AES256", "cipher name is not set to AES256: %s" % v.cipher_name

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@ -0,0 +1,141 @@
#!/usr/bin/env python
from unittest import TestCase
import getpass
import os
import shutil
import time
import tempfile
from binascii import unhexlify
from binascii import hexlify
from nose.plugins.skip import SkipTest
from ansible import errors
from ansible.utils.vault import VaultLib
from ansible.utils.vault import VaultEditor
# Counter import fails for 2.0.1, requires >= 2.6.1 from pip
try:
from Crypto.Util import Counter
HAS_COUNTER = True
except ImportError:
HAS_COUNTER = False
# KDF import fails for 2.0.1, requires >= 2.6.1 from pip
try:
from Crypto.Protocol.KDF import PBKDF2
HAS_PBKDF2 = True
except ImportError:
HAS_PBKDF2 = False
# AES IMPORTS
try:
from Crypto.Cipher import AES as AES
HAS_AES = True
except ImportError:
HAS_AES = False
class TestVaultEditor(TestCase):
def test_methods_exist(self):
v = VaultEditor(None, None, None)
slots = ['create_file',
'decrypt_file',
'edit_file',
'encrypt_file',
'rekey_file',
'read_data',
'write_data',
'shuffle_files']
for slot in slots:
assert hasattr(v, slot), "VaultLib is missing the %s method" % slot
def test_decrypt_1_0(self):
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise SkipTest
dirpath = tempfile.mkdtemp()
filename = os.path.join(dirpath, "foo-ansible-1.0.yml")
shutil.rmtree(dirpath)
shutil.copytree("vault_test_data", dirpath)
ve = VaultEditor(None, "ansible", filename)
# make sure the password functions for the cipher
error_hit = False
try:
ve.decrypt_file()
except errors.AnsibleError, e:
error_hit = True
# verify decrypted content
f = open(filename, "rb")
fdata = f.read()
f.close()
shutil.rmtree(dirpath)
assert error_hit == False, "error decrypting 1.0 file"
assert fdata.strip() == "foo", "incorrect decryption of 1.0 file: %s" % fdata.strip()
def test_decrypt_1_1(self):
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise SkipTest
dirpath = tempfile.mkdtemp()
filename = os.path.join(dirpath, "foo-ansible-1.1.yml")
shutil.rmtree(dirpath)
shutil.copytree("vault_test_data", dirpath)
ve = VaultEditor(None, "ansible", filename)
# make sure the password functions for the cipher
error_hit = False
try:
ve.decrypt_file()
except errors.AnsibleError, e:
error_hit = True
# verify decrypted content
f = open(filename, "rb")
fdata = f.read()
f.close()
shutil.rmtree(dirpath)
assert error_hit == False, "error decrypting 1.0 file"
assert fdata.strip() == "foo", "incorrect decryption of 1.0 file: %s" % fdata.strip()
def test_rekey_migration(self):
if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
raise SkipTest
dirpath = tempfile.mkdtemp()
filename = os.path.join(dirpath, "foo-ansible-1.0.yml")
shutil.rmtree(dirpath)
shutil.copytree("vault_test_data", dirpath)
ve = VaultEditor(None, "ansible", filename)
# make sure the password functions for the cipher
error_hit = False
try:
ve.rekey_file('ansible2')
except errors.AnsibleError, e:
error_hit = True
# verify decrypted content
f = open(filename, "rb")
fdata = f.read()
f.close()
shutil.rmtree(dirpath)
assert error_hit == False, "error rekeying 1.0 file to 1.1"
# ensure filedata can be decrypted, is 1.1 and is AES256
vl = VaultLib("ansible2")
dec_data = None
error_hit = False
try:
dec_data = vl.decrypt(fdata)
except errors.AnsibleError, e:
error_hit = True
assert vl.cipher_name == "AES256", "wrong cipher name set after rekey: %s" % vl.cipher_name
assert error_hit == False, "error decrypting migrated 1.0 file"
assert dec_data.strip() == "foo", "incorrect decryption of rekeyed/migrated file: %s" % dec_data

View file

@ -0,0 +1,4 @@
$ANSIBLE_VAULT;1.0;AES
53616c7465645f5fd0026926a2d415a28a2622116273fbc90e377225c12a347e1daf4456d36a77f9
9ad98d59f61d06a4b66718d855f16fb7bdfe54d1ec8aeaa4d06c2dc1fa630ae1846a029877f0eeb1
83c62ffb04c2512995e815de4b4d29ed

View file

@ -0,0 +1,6 @@
$ANSIBLE_VAULT;1.1;AES256
62303130653266653331306264616235333735323636616539316433666463323964623162386137
3961616263373033353631316333623566303532663065310a393036623466376263393961326530
64336561613965383835646464623865663966323464653236343638373165343863623638316664
3631633031323837340a396530313963373030343933616133393566366137363761373930663833
3739