def testStrict1(self):
number = DerInteger()
number.decode(b'\x02\x02\x00\x01')
number.decode(b'\x02\x02\x00\x7F')
self.assertRaises(ValueError, number.decode, b'\x02\x02\x00\x01', strict=True)
self.assertRaises(ValueError, number.decode, b'\x02\x02\x00\x7F', strict=True)
def testDecode2(self):
# Multi-byte integer
der = DerInteger()
# Value 0x180L
der.decode(b('\x02\x02\x01\x80'))
self.assertEqual(der.value,0x180)
# One very long integer
der.decode(
b('\x02\x82\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00'))
self.assertEqual(der.value,2**2048)
def testDecode3(self):
# Negative integer
der = DerInteger()
# Value -1
der.decode(b('\x02\x01\xFF'))
self.assertEqual(der.value, -1)
# Value -32768
der.decode(b('\x02\x02\x80\x00'))
self.assertEqual(der.value, -32768)
def testEncode1(self):
# Single-byte integers
# Value 0
der = DerInteger(0)
self.assertEqual(der.encode(), b('\x02\x01\x00'))
# Value 1
der = DerInteger(1)
self.assertEqual(der.encode(), b('\x02\x01\x01'))
# Value 127
der = DerInteger(127)
self.assertEqual(der.encode(), b('\x02\x01\x7F'))
def testEncode3(self):
# Negative integers
# Value -1
der = DerInteger(-1)
self.assertEqual(der.encode(), b('\x02\x01\xFF'))
# Value -128
der = DerInteger(-128)
self.assertEqual(der.encode(), b('\x02\x01\x80'))
# Value
der = DerInteger(-87873)
self.assertEqual(der.encode(), b('\x02\x03\xFE\xA8\xBF'))
def _extract_sp_info(x509_certificate):
"""Extract subjectPublicKeyInfo from a DER X.509 certificate."""
from Crypto.Util.asn1 import DerSequence, DerInteger
try:
# This code will partially parse tbsCertificate
# to get to subjectPublicKeyInfo.
#
# However, the first 2 elements of tbsCertificate are:
#
# version [0] Version DEFAULT v1,
# serialNumber CertificateSerialNumber,
#
# where:
#
# Version ::= INTEGER { v1(0), v2(1), v3(2) }
# CertificateSerialNumber ::= INTEGER
#
# In order to know the position of subjectPublicKeyInfo
# in the tbsCertificate SEQUENCE, we try to see if the
# first element is an untagged INTEGER (that is, the
# certificate serial number).
x509_tbs_cert = DerSequence()
x509_tbs_cert.decode(x509_certificate[0])
index = -1 # Sentinel
try:
_ = x509_tbs_cert[0] + 1
# Still here? There was no version then
index = 5
except TypeError:
# Landed here? Version was there
x509_version = DerInteger(explicit=0)
x509_version.decode(x509_tbs_cert[0])
index = 6
if index in (5, 6):
return x509_tbs_cert[index]
except (TypeError, IndexError, ValueError, EOFError):
pass
raise ValueError("Cannot extract subjectPublicKeyInfo")
def _import_pkcs8(encoded, passphrase, params):
if params:
raise ValueError("PKCS#8 already includes parameters")
k = PKCS8.unwrap(encoded, passphrase)
if k[0] != oid:
raise ValueError("No PKCS#8 encoded DSA key")
x = DerInteger().decode(k[1]).value
p, q, g = list(DerSequence().decode(k[2]))
tup = (pow(g, x, p), g, p, q, x)
return construct(tup)
def testDecode1(self):
# Single-byte integer
der = DerInteger()
# Value 0
der.decode(b('\x02\x01\x00'))
self.assertEquals(der.value, 0)
# Value 1
der.decode(b('\x02\x01\x01'))
self.assertEquals(der.value, 1)
# Value 127
der.decode(b('\x02\x01\x7F'))
self.assertEquals(der.value, 127)
def testDecode5(self):
# We still accept BER integer format
der = DerInteger()
# Redundant leading zeroes
der.decode(b('\x02\x02\x00\x01'))
self.assertEquals(der.value, 1)
# Redundant leading 0xFF
der.decode(b('\x02\x02\xFF\xFF'))
self.assertEquals(der.value, -1)
# Empty payload
der.decode(b('\x02\x00'))
self.assertEquals(der.value, 0)
def _import_subjectPublicKeyInfo(encoded, passphrase, params):
algoid, encoded_key, emb_params = _expand_subject_public_key_info(encoded)
if algoid != oid:
raise ValueError("No DSA subjectPublicKeyInfo")
if params and emb_params:
raise ValueError("Too many DSA parameters")
y = DerInteger().decode(encoded_key).value
p, q, g = list(DerSequence().decode(params or emb_params))
tup = (y, g, p, q)
return construct(tup)
def testDecode2(self):
# Multi-byte integer
der = DerInteger()
# Value 0x180L
der.decode(b('\x02\x02\x01\x80'))
self.assertEquals(der.value, 0x180L)
# One very long integer
der.decode(
b('\x02\x82\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00') +
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00'))
self.assertEquals(der.value, 2L**2048)
def testEncode2(self):
# Multi-byte integers
# Value 128
der = DerInteger(128)
self.assertEqual(der.encode(), b('\x02\x02\x00\x80'))
# Value 0x180
der = DerInteger(0x180)
self.assertEqual(der.encode(), b('\x02\x02\x01\x80'))
# One very long integer
der = DerInteger(2**2048)
self.assertEqual(der.encode(),
b('\x02\x82\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')+
b('\x00\x00\x00\x00\x00\x00\x00\x00\x00'))
def testDecode5(self):
# We still accept BER integer format
der = DerInteger()
# Redundant leading zeroes
der.decode(b('\x02\x02\x00\x01'))
self.assertEqual(der.value, 1)
# Redundant leading 0xFF
der.decode(b('\x02\x02\xFF\xFF'))
self.assertEqual(der.value, -1)
# Empty payload
der.decode(b('\x02\x00'))
self.assertEqual(der.value, 0)
def testDecode1(self):
# Single-byte integer
der = DerInteger()
# Value 0
der.decode(b('\x02\x01\x00'))
self.assertEqual(der.value, 0)
# Value 1
der.decode(b('\x02\x01\x01'))
self.assertEqual(der.value, 1)
# Value 127
der.decode(b('\x02\x01\x7F'))
self.assertEqual(der.value, 127)
def testDecode3(self):
# Negative integer
der = DerInteger()
# Value -1
der.decode(b('\x02\x01\xFF'))
self.assertEquals(der.value, -1)
# Value -32768
der.decode(b('\x02\x02\x80\x00'))
self.assertEquals(der.value, -32768)
def testEncode1(self):
# Single-byte integers
# Value 0
der = DerInteger(0)
self.assertEqual(der.encode(), b('\x02\x01\x00'))
# Value 1
der = DerInteger(1)
self.assertEqual(der.encode(), b('\x02\x01\x01'))
# Value 127
der = DerInteger(127)
self.assertEqual(der.encode(), b('\x02\x01\x7F'))
def testEncode3(self):
# Negative integers
# Value -1
der = DerInteger(-1)
self.assertEqual(der.encode(), b('\x02\x01\xFF'))
# Value -128
der = DerInteger(-128)
self.assertEqual(der.encode(), b('\x02\x01\x80'))
# Value
der = DerInteger(-87873)
self.assertEqual(der.encode(), b('\x02\x03\xFE\xA8\xBF'))
def _extract_subject_public_key_info(x509_certificate):
"""Extract subjectPublicKeyInfo from a DER X.509 certificate."""
certificate = DerSequence().decode(x509_certificate, nr_elements=3)
tbs_certificate = DerSequence().decode(certificate[0],
nr_elements=list(range(6, 11)))
index = 5
try:
tbs_certificate[0] + 1
# Version not present
version = 1
except TypeError:
version = DerInteger(explicit=0).decode(tbs_certificate[0]).value
if version not in (2, 3):
raise ValueError("Incorrect X.509 certificate version")
index = 6
return tbs_certificate[index]
def testInit1(self):
der = newDerSetOf(DerInteger(1), DerInteger(2))
self.assertEqual(der.encode(), b('1\x06\x02\x01\x01\x02\x01\x02'))
def testInit1(self):
der = DerInteger(1)
self.assertEqual(der.encode(), b('\x02\x01\x01'))
def testEncode4(self):
# Explicit encoding
number = DerInteger(0x34, explicit=3)
self.assertEquals(number.encode(), b('\xa3\x03\x02\x01\x34'))
def testInit1(self):
der = newDerSequence(1, DerInteger(2), '0\x00')
self.assertEqual(der.encode(), b('0\x08\x02\x01\x01\x02\x01\x020\x00'))
def exportKey(self,
format='PEM',
pkcs8=None,
passphrase=None,
protection=None,
randfunc=None):
"""Export this DSA key.
Args:
format (string):
The encoding for the output:
- *'PEM'* (default). ASCII as per `RFC1421`_/ `RFC1423`_.
- *'DER'*. Binary ASN.1 encoding.
- *'OpenSSH'*. ASCII one-liner as per `RFC4253`_.
Only suitable for public keys, not for private keys.
passphrase (string):
*Private keys only*. The pass phrase to protect the output.
pkcs8 (boolean):
*Private keys only*. If ``True`` (default), the key is encoded
with `PKCS#8`_. If ``False``, it is encoded in the custom
OpenSSL/OpenSSH container.
protection (string):
*Only in combination with a pass phrase*.
The encryption scheme to use to protect the output.
If :data:`pkcs8` takes value ``True``, this is the PKCS#8
algorithm to use for deriving the secret and encrypting
the private DSA key.
For a complete list of algorithms, see :mod:`Crypto.IO.PKCS8`.
The default is *PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC*.
If :data:`pkcs8` is ``False``, the obsolete PEM encryption scheme is
used. It is based on MD5 for key derivation, and Triple DES for
encryption. Parameter :data:`protection` is then ignored.
The combination ``format='DER'`` and ``pkcs8=False`` is not allowed
if a passphrase is present.
randfunc (callable):
A function that returns random bytes.
By default it is :func:`Crypto.Random.get_random_bytes`.
Returns:
byte string : the encoded key
Raises:
ValueError : when the format is unknown or when you try to encrypt a private
key with *DER* format and OpenSSL/OpenSSH.
.. warning::
If you don't provide a pass phrase, the private key will be
exported in the clear!
.. _RFC1421: http://www.ietf.org/rfc/rfc1421.txt
.. _RFC1423: http://www.ietf.org/rfc/rfc1423.txt
.. _RFC4253: http://www.ietf.org/rfc/rfc4253.txt
.. _`PKCS#8`: http://www.ietf.org/rfc/rfc5208.txt
"""
if passphrase is not None:
passphrase = tobytes(passphrase)
if randfunc is None:
randfunc = Random.get_random_bytes
if format == 'OpenSSH':
tup1 = [self._key[x].to_bytes() for x in ('p', 'q', 'g', 'y')]
def func(x):
if (bord(x[0]) & 0x80):
return bchr(0) + x
else:
return x
tup2 = list(map(func, tup1))
keyparts = [b('ssh-dss')] + tup2
keystring = b('').join(
[struct.pack(">I", len(kp)) + kp for kp in keyparts])
return b('ssh-dss ') + binascii.b2a_base64(keystring)[:-1]
# DER format is always used, even in case of PEM, which simply
# encodes it into BASE64.
params = DerSequence([self.p, self.q, self.g])
if self.has_private():
if pkcs8 is None:
pkcs8 = True
if pkcs8:
if not protection:
protection = 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC'
private_key = DerInteger(self.x).encode()
binary_key = PKCS8.wrap(private_key,
oid,
passphrase,
protection,
key_params=params,
randfunc=randfunc)
if passphrase:
key_type = 'ENCRYPTED PRIVATE'
else:
key_type = 'PRIVATE'
passphrase = None
else:
if format != 'PEM' and passphrase:
raise ValueError("DSA private key cannot be encrypted")
ints = [0, self.p, self.q, self.g, self.y, self.x]
binary_key = DerSequence(ints).encode()
key_type = "DSA PRIVATE"
else:
if pkcs8:
raise ValueError("PKCS#8 is only meaningful for private keys")
binary_key = _create_subject_public_key_info(
oid, DerInteger(self.y), params)
key_type = "PUBLIC"
if format == 'DER':
return binary_key
if format == 'PEM':
pem_str = PEM.encode(binary_key, key_type + " KEY", passphrase,
randfunc)
return tobytes(pem_str)
raise ValueError(
"Unknown key format '%s'. Cannot export the DSA key." % format)
def testInit2(self):
der = DerBitString(DerInteger(1))
self.assertEquals(der.encode(), b('\x03\x04\x00\x02\x01\x01'))
def testErrDecode1(self):
# Wide length field
der = DerInteger()
self.assertRaises(ValueError, der.decode, b('\x02\x81\x01\x01'))
def testDecode6(self):
# Explicit encoding
number = DerInteger(explicit=3)
number.decode(b('\xa3\x03\x02\x01\x34'))
self.assertEquals(number.value, 0x34)
def testEncode4(self):
# Explicit encoding
number = DerInteger(0x34, explicit=3)
self.assertEqual(number.encode(), b('\xa3\x03\x02\x01\x34'))
def testDecode7(self):
# Verify decode returns the DerInteger
der = DerInteger()
self.assertEquals(der, der.decode(b('\x02\x01\x7F')))
def exportKey(self, format='PEM', pkcs8=None, passphrase=None,
protection=None, randfunc=None):
"""Export this DSA key.
:Parameters:
format : string
The format to use for wrapping the key:
- *'DER'*. Binary encoding.
- *'PEM'*. Textual encoding, done according to `RFC1421`_/
`RFC1423`_ (default).
- *'OpenSSH'*. Textual encoding, one line of text, see `RFC4253`_.
Only suitable for public keys, not private keys.
passphrase : string
For private keys only. The pass phrase to use for deriving
the encryption key.
pkcs8 : boolean
For private keys only. If ``True`` (default), the key is arranged
according to `PKCS#8`_ and if `False`, according to the custom
OpenSSL/OpenSSH encoding.
protection : string
The encryption scheme to use for protecting the private key.
It is only meaningful when a pass phrase is present too.
If ``pkcs8`` takes value ``True``, ``protection`` is the PKCS#8
algorithm to use for deriving the secret and encrypting
the private DSA key.
For a complete list of algorithms, see `Crypto.IO.PKCS8`.
The default is *PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC*.
If ``pkcs8`` is ``False``, the obsolete PEM encryption scheme is
used. It is based on MD5 for key derivation, and Triple DES for
encryption. Parameter ``protection`` is ignored.
The combination ``format='DER'`` and ``pkcs8=False`` is not allowed
if a passphrase is present.
randfunc : callable
A function that returns random bytes.
By default it is `Crypto.Random.get_random_bytes`.
:Return: A byte string with the encoded public or private half
of the key.
:Raise ValueError:
When the format is unknown or when you try to encrypt a private
key with *DER* format and OpenSSL/OpenSSH.
:attention:
If you don't provide a pass phrase, the private key will be
exported in the clear!
.. _RFC1421: http://www.ietf.org/rfc/rfc1421.txt
.. _RFC1423: http://www.ietf.org/rfc/rfc1423.txt
.. _RFC4253: http://www.ietf.org/rfc/rfc4253.txt
.. _`PKCS#8`: http://www.ietf.org/rfc/rfc5208.txt
"""
if passphrase is not None:
passphrase = tobytes(passphrase)
if randfunc is None:
randfunc = Random.get_random_bytes
if format == 'OpenSSH':
tup1 = [self._key[x].to_bytes() for x in 'p', 'q', 'g', 'y']
def func(x):
if (bord(x[0]) & 0x80):
return bchr(0) + x
else:
return x
tup2 = map(func, tup1)
keyparts = [b('ssh-dss')] + tup2
keystring = b('').join(
[struct.pack(">I", len(kp)) + kp for kp in keyparts]
)
return b('ssh-dss ') + binascii.b2a_base64(keystring)[:-1]
# DER format is always used, even in case of PEM, which simply
# encodes it into BASE64.
params = newDerSequence(self.p, self.q, self.g)
if self.has_private():
if pkcs8 is None:
pkcs8 = True
if pkcs8:
if not protection:
protection = 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC'
private_key = DerInteger(self.x).encode()
binary_key = PKCS8.wrap(
private_key, oid, passphrase,
protection, key_params=params,
randfunc=randfunc
)
if passphrase:
key_type = 'ENCRYPTED PRIVATE'
else:
key_type = 'PRIVATE'
passphrase = None
else:
if format != 'PEM' and passphrase:
raise ValueError("DSA private key cannot be encrypted")
ints = [0, self.p, self.q, self.g, self.y, self.x]
binary_key = newDerSequence(*ints).encode()
key_type = "DSA PRIVATE"
else:
if pkcs8:
raise ValueError("PKCS#8 is only meaningful for private keys")
binary_key = newDerSequence(
newDerSequence(DerObjectId(oid), params),
newDerBitString(DerInteger(self.y))
).encode()
key_type = "DSA PUBLIC"
if format == 'DER':
return binary_key
if format == 'PEM':
pem_str = PEM.encode(
binary_key, key_type + " KEY",
passphrase, randfunc
)
return tobytes(pem_str)
raise ValueError("Unknown key format '%s'. Cannot export the DSA key." % format)
def testInit1(self):
der = DerSequence([1, DerInteger(2), b('0\x00')])
self.assertEquals(der.encode(),
b('0\x08\x02\x01\x01\x02\x01\x020\x00'))
def test_int_encoder_big_test(self):
for i in range(1000):
k = random.randint(0, 1000**1000)
corr_ans = str(hexlify(DerInteger(k).encode()))[2:][:-1]
imp_ans = main.encode_integer_tlv(k)
self.assertEqual(corr_ans, imp_ans)
def testInit1(self):
der = DerSetOf([DerInteger(1), DerInteger(2)])
self.assertEquals(der.encode(), b('1\x06\x02\x01\x01\x02\x01\x02'))
def testDecode7(self):
# Verify decode returns the DerInteger
der = DerInteger()
self.assertEqual(der, der.decode(b('\x02\x01\x7F')))
def testInit1(self):
der = DerInteger(1)
self.assertEquals(der.encode(), b('\x02\x01\x01'))
def exportKey(self,
format='PEM',
pkcs8=None,
passphrase=None,
protection=None):
if passphrase is not None:
passphrase = tobytes(passphrase)
if format == 'OpenSSH':
tup1 = [long_to_bytes(x) for x in (self.p, self.q, self.g, self.y)]
def func(x):
if bord(x[0]) & 128:
return bchr(0) + x
else:
return x
tup2 = map(func, tup1)
keyparts = [b('ssh-dss')] + tup2
keystring = b('').join(
[struct.pack('>I', len(kp)) + kp for kp in keyparts])
return b('ssh-dss ') + binascii.b2a_base64(keystring)[:-1]
else:
params = newDerSequence(self.p, self.q, self.g)
if self.has_private():
if pkcs8 is None:
pkcs8 = True
if pkcs8:
if not protection:
protection = 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC'
private_key = DerInteger(self.x).encode()
binary_key = PKCS8.wrap(private_key,
oid,
passphrase,
protection,
key_params=params,
randfunc=self._randfunc)
if passphrase:
key_type = 'ENCRYPTED PRIVATE'
else:
key_type = 'PRIVATE'
passphrase = None
else:
if format != 'PEM' and passphrase:
raise ValueError('DSA private key cannot be encrypted')
ints = [0, self.p, self.q, self.g, self.y, self.x]
binary_key = newDerSequence(*ints).encode()
key_type = 'DSA PRIVATE'
else:
if pkcs8:
raise ValueError(
'PKCS#8 is only meaningful for private keys')
binary_key = newDerSequence(
newDerSequence(DerObjectId(oid), params),
newDerBitString(DerInteger(self.y))).encode()
key_type = 'DSA PUBLIC'
if format == 'DER':
return binary_key
if format == 'PEM':
pem_str = PEM.encode(binary_key, key_type + ' KEY', passphrase,
self._randfunc)
return tobytes(pem_str)
raise ValueError(
"Unknown key format '%s'. Cannot export the DSA key." % format)
return
def encrypt(data, passphrase, protection, prot_params=None, randfunc=None):
"""Encrypt a piece of data using a passphrase and *PBES2*.
:Parameters:
data : byte string
The piece of data to encrypt.
passphrase : byte string
The passphrase to use for encrypting the data.
protection : string
The identifier of the encryption algorithm to use.
The default value is '``PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC``'.
prot_params : dictionary
Parameters of the protection algorithm.
+------------------+-----------------------------------------------+
| Key | Description |
+==================+===============================================+
| iteration_count | The KDF algorithm is repeated several times to|
| | slow down brute force attacks on passwords |
| | (called *N* or CPU/memory cost in scrypt). |
| | |
| | The default value for PBKDF2 is 1 000. |
| | The default value for scrypt is 16 384. |
+------------------+-----------------------------------------------+
| salt_size | Salt is used to thwart dictionary and rainbow |
| | attacks on passwords. The default value is 8 |
| | bytes. |
+------------------+-----------------------------------------------+
| block_size | *(scrypt only)* Memory-cost (r). The default |
| | value is 8. |
+------------------+-----------------------------------------------+
| parallelization | *(scrypt only)* CPU-cost (p). The default |
| | value is 1. |
+------------------+-----------------------------------------------+
randfunc : callable
Random number generation function; it should accept
a single integer N and return a string of random data,
N bytes long. If not specified, a new RNG will be
instantiated from ``Crypto.Random``.
:Returns:
The encrypted data, as a binary string.
"""
if prot_params is None:
prot_params = {}
if randfunc is None:
randfunc = Random.new().read
if protection == 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC':
key_size = 24
module = DES3
cipher_mode = DES3.MODE_CBC
enc_oid = "1.2.840.113549.3.7"
elif protection in ('PBKDF2WithHMAC-SHA1AndAES128-CBC',
'scryptAndAES128-CBC'):
key_size = 16
module = AES
cipher_mode = AES.MODE_CBC
enc_oid = "2.16.840.1.101.3.4.1.2"
elif protection in ('PBKDF2WithHMAC-SHA1AndAES192-CBC',
'scryptAndAES192-CBC'):
key_size = 24
module = AES
cipher_mode = AES.MODE_CBC
enc_oid = "2.16.840.1.101.3.4.1.22"
elif protection in ('PBKDF2WithHMAC-SHA1AndAES256-CBC',
'scryptAndAES256-CBC'):
key_size = 32
module = AES
cipher_mode = AES.MODE_CBC
enc_oid = "2.16.840.1.101.3.4.1.42"
else:
raise ValueError("Unknown mode")
# Get random data
iv = randfunc(module.block_size)
salt = randfunc(prot_params.get("salt_size", 8))
# Derive key from password
if protection.startswith('PBKDF2'):
count = prot_params.get("iteration_count", 1000)
key = PBKDF2(passphrase, salt, key_size, count)
key_derivation_func = newDerSequence(
DerObjectId("1.2.840.113549.1.5.12"), # PBKDF2
newDerSequence(DerOctetString(salt), DerInteger(count)))
else:
# It must be scrypt
count = prot_params.get("iteration_count", 16384)
scrypt_r = prot_params.get('block_size', 8)
scrypt_p = prot_params.get('parallelization', 1)
key = scrypt(passphrase, salt, key_size, count, scrypt_r, scrypt_p)
key_derivation_func = newDerSequence(
DerObjectId("1.3.6.1.4.1.11591.4.11"), # scrypt
newDerSequence(DerOctetString(salt), DerInteger(count),
DerInteger(scrypt_r), DerInteger(scrypt_p)))
# Create cipher and use it
cipher = module.new(key, cipher_mode, iv)
encrypted_data = cipher.encrypt(pad(data, cipher.block_size))
encryption_scheme = newDerSequence(DerObjectId(enc_oid),
DerOctetString(iv))
# Result
encrypted_private_key_info = newDerSequence(
# encryptionAlgorithm
newDerSequence(
DerObjectId("1.2.840.113549.1.5.13"), # PBES2
newDerSequence(key_derivation_func, encryption_scheme),
),
DerOctetString(encrypted_data))
return encrypted_private_key_info.encode()
def testDecode6(self):
# Explicit encoding
number = DerInteger(explicit=3)
number.decode(b('\xa3\x03\x02\x01\x34'))
self.assertEqual(number.value, 0x34)
def _importKeyDER(key_data, passphrase, params):
"""Import a DSA key (public or private half), encoded in DER form."""
try:
#
# Dss-Parms ::= SEQUENCE {
# p OCTET STRING,
# q OCTET STRING,
# g OCTET STRING
# }
#
# Try a simple private key first
if params:
x = DerInteger().decode(key_data).value
p, q, g = list(DerSequence().decode(params)) # Dss-Parms
tup = (pow(g, x, p), g, p, q, x)
return construct(tup)
der = DerSequence().decode(key_data)
# Try OpenSSL format for private keys
if len(der) == 6 and der.hasOnlyInts() and der[0] == 0:
tup = [der[comp] for comp in (4, 3, 1, 2, 5)]
return construct(tup)
# Try SubjectPublicKeyInfo
if len(der) == 2:
try:
algo = DerSequence().decode(der[0])
algo_oid = DerObjectId().decode(algo[0]).value
params = DerSequence().decode(algo[1]) # Dss-Parms
if algo_oid == oid and len(params) == 3 and\
params.hasOnlyInts():
bitmap = DerBitString().decode(der[1])
pub_key = DerInteger().decode(bitmap.value)
tup = [pub_key.value]
tup += [params[comp] for comp in (2, 0, 1)]
return construct(tup)
except (ValueError, EOFError):
pass
# Try to see if this is an X.509 DER certificate
# (Certificate ASN.1 type)
if len(der) == 3:
from Crypto.PublicKey import _extract_sp_info
try:
sp_info = _extract_sp_info(der)
return _importKeyDER(sp_info, passphrase, None)
except ValueError:
pass
# Try unencrypted PKCS#8
p8_pair = PKCS8.unwrap(key_data, passphrase)
if p8_pair[0] == oid:
return _importKeyDER(p8_pair[1], passphrase, p8_pair[2])
except (ValueError, EOFError):
pass
raise ValueError("DSA key format is not supported")
def test_int_encoder_liveq(self):
k = 141200904527031427693111569572085332763291092089246046288015799505524112848666951727490655634310664507006287247690643568683363763333057271478359004846665350192723231859612961899401338906920115912147935812300211873100787356909246033420333758668256600284274201300130421437978238102757977633689474423065331072603
corr_ans = str(hexlify(DerInteger(k).encode()))[2:][:-1]
print("\n\n" + main.encode_integer_tlv(k) + "\n\n")
self.assertEqual(corr_ans, main.encode_integer_tlv(k))
