def exportKey(self,
format='PEM',
passphrase=None,
pkcs=1,
protection=None):
if passphrase is not None:
passphrase = tobytes(passphrase)
if format == 'OpenSSH':
eb = long_to_bytes(self.e)
nb = long_to_bytes(self.n)
if bord(eb[0]) & 128:
eb = bchr(0) + eb
if bord(nb[0]) & 128:
nb = bchr(0) + nb
keyparts = [b('ssh-rsa'), eb, nb]
keystring = b('').join(
[struct.pack('>I', len(kp)) + kp for kp in keyparts])
return b('ssh-rsa ') + binascii.b2a_base64(keystring)[:-1]
else:
if self.has_private():
binary_key = newDerSequence(0, self.n, self.e, self.d, self.p,
self.q, self.d % (self.p - 1),
self.d % (self.q - 1),
inverse(self.q, self.p)).encode()
if pkcs == 1:
keyType = 'RSA PRIVATE'
if format == 'DER' and passphrase:
raise ValueError(
'PKCS#1 private key cannot be encrypted')
elif format == 'PEM' and protection is None:
keyType = 'PRIVATE'
binary_key = PKCS8.wrap(binary_key, oid, None)
else:
keyType = 'ENCRYPTED PRIVATE'
if not protection:
protection = 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC'
binary_key = PKCS8.wrap(binary_key, oid, passphrase,
protection)
passphrase = None
else:
keyType = 'RSA PUBLIC'
binary_key = newDerSequence(
algorithmIdentifier,
newDerBitString(newDerSequence(self.n, self.e))).encode()
if format == 'DER':
return binary_key
if format == 'PEM':
pem_str = PEM.encode(binary_key, keyType + ' KEY', passphrase,
self._randfunc)
return tobytes(pem_str)
raise ValueError(
"Unknown key format '%s'. Cannot export the RSA key." % format)
return
def _importKeyDER(self, extern_key, passphrase=None):
try:
der = decode_der(DerSequence, extern_key)
if len(der) == 9 and der.hasOnlyInts() and der[0] == 0:
del der[6:]
der.append(inverse(der[4], der[5]))
del der[0]
return self.construct(der[:])
if len(der) == 2:
try:
if der.hasOnlyInts():
return self.construct(der[:])
if der[0] == algorithmIdentifier:
bitmap = decode_der(DerBitString, der[1])
rsaPub = decode_der(DerSequence, bitmap.value)
if len(rsaPub) == 2 and rsaPub.hasOnlyInts():
return self.construct(rsaPub[:])
except (ValueError, EOFError):
pass
k = PKCS8.unwrap(extern_key, passphrase)
if k[0] == oid:
return self._importKeyDER(k[1], passphrase)
except (ValueError, EOFError):
pass
raise ValueError('RSA key format is not supported')
def test3(self):
"""Verify unwrapping with encryption"""
for t in self.wrapped_enc_keys:
res1, res2, res3 = PKCS8.unwrap(t[4], b("TestTest"))
self.assertEqual(res1, self.oid_key)
self.assertEqual(res2, self.clear_key)
def _importKeyDER(self, key_data, passphrase=None, params=None):
try:
if params:
x = decode_der(DerInteger, key_data).value
params = decode_der(DerSequence, params)
p, q, g = list(params)
y = pow(g, x, p)
tup = (y, g, p, q, x)
return self.construct(tup)
der = decode_der(DerSequence, key_data)
if len(der) == 6 and der.hasOnlyInts() and der[0] == 0:
tup = [der[comp] for comp in (4, 3, 1, 2, 5)]
return self.construct(tup)
if len(der) == 2:
try:
algo = decode_der(DerSequence, der[0])
algo_oid = decode_der(DerObjectId, algo[0]).value
params = decode_der(DerSequence, algo[1])
if algo_oid == oid and len(
params) == 3 and params.hasOnlyInts():
bitmap = decode_der(DerBitString, der[1])
pub_key = decode_der(DerInteger, bitmap.value)
tup = [pub_key.value]
tup += [params[comp] for comp in (2, 0, 1)]
return self.construct(tup)
except (ValueError, EOFError):
pass
p8_pair = PKCS8.unwrap(key_data, passphrase)
if p8_pair[0] == oid:
return self._importKeyDER(p8_pair[1], passphrase, p8_pair[2])
except (ValueError, EOFError):
pass
raise ValueError('DSA key format is not supported')
def test3(self):
"""Verify unwrapping with encryption"""
for t in self.wrapped_enc_keys:
res1, res2, res3 = PKCS8.unwrap(t[4], b("TestTest"))
self.assertEqual(res1, self.oid_key)
self.assertEqual(res2, self.clear_key)
def _import_pkcs8(encoded, passphrase):
from Crypto.IO import PKCS8
k = PKCS8.unwrap(encoded, passphrase)
if k[0] != oid:
raise ValueError("No PKCS#8 encoded RSA key")
return _import_keyDER(k[1], passphrase)
def _import_pkcs8(encoded, passphrase):
from Crypto.IO import PKCS8
# From RFC5915, Section 1:
#
# Distributing an EC private key with PKCS#8 [RFC5208] involves including:
# a) id-ecPublicKey, id-ecDH, or id-ecMQV (from [RFC5480]) with the
# namedCurve as the parameters in the privateKeyAlgorithm field; and
# b) ECPrivateKey in the PrivateKey field, which is an OCTET STRING.
algo_oid, private_key, params = PKCS8.unwrap(encoded, passphrase)
# We accept id-ecPublicKey, id-ecDH, id-ecMQV without making any
# distiction for now.
unrestricted_oid = "1.2.840.10045.2.1"
ecdh_oid = "1.3.132.1.12"
ecmqv_oid = "1.3.132.1.13"
if algo_oid not in (unrestricted_oid, ecdh_oid, ecmqv_oid):
raise UnsupportedEccFeature("Unsupported ECC purpose (OID: %s)" %
algo_oid)
curve_oid = DerObjectId().decode(params).value
return _import_private_der(private_key, passphrase, curve_oid)
def _importKeyDER(extern_key, passphrase, verify_x509_cert):
"""Import an RSA key (public or private half), encoded in DER form."""
try:
der = DerSequence().decode(extern_key)
# Try PKCS#1 first, for a private key
if len(der) == 9 and der.hasOnlyInts() and der[0] == 0:
# ASN.1 RSAPrivateKey element
del der[6:] # Remove d mod (p-1),
# d mod (q-1), and
# q^{-1} mod p
der.append(Integer(der[4]).inverse(der[5])) # Add p^{-1} mod q
del der[0] # Remove version
return construct(der[:])
# Keep on trying PKCS#1, but now for a public key
if len(der) == 2:
try:
# The DER object is an RSAPublicKey SEQUENCE with
# two elements
if der.hasOnlyInts():
return construct(der[:])
# The DER object is a SubjectPublicKeyInfo SEQUENCE
# with two elements: an 'algorithmIdentifier' and a
# 'subjectPublicKey'BIT STRING.
# 'algorithmIdentifier' takes the value given at the
# module level.
# 'subjectPublicKey' encapsulates the actual ASN.1
# RSAPublicKey element.
if der[0] == algorithmIdentifier:
bitmap = DerBitString().decode(der[1])
rsaPub = DerSequence().decode(bitmap.value)
if len(rsaPub) == 2 and rsaPub.hasOnlyInts():
return construct(rsaPub[:])
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)
if verify_x509_cert:
raise NotImplementedError("X.509 certificate validation is not supported")
return _importKeyDER(sp_info, passphrase, False)
except ValueError:
pass
# Try PKCS#8 (possibly encrypted)
k = PKCS8.unwrap(extern_key, passphrase)
if k[0] == oid:
return _importKeyDER(k[1], passphrase, False)
except (ValueError, EOFError):
pass
raise ValueError("RSA key format is not supported")
def _export_pkcs8(self, **kwargs):
if kwargs.get('passphrase', None) is not None and 'protection' not in kwargs:
raise ValueError("At least the 'protection' parameter should be present")
unrestricted_oid = "1.2.840.10045.2.1"
private_key = self._export_private_der(include_ec_params=False)
result = PKCS8.wrap(private_key,
unrestricted_oid,
key_params=DerObjectId(_curve.oid),
**kwargs)
return result
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 _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 _export_pkcs8(self, **kwargs):
if kwargs.get('passphrase', None) is not None and 'protection' not in kwargs:
raise ValueError("At least the 'protection' parameter should be present")
unrestricted_oid = "1.2.840.10045.2.1"
private_key = self._export_private_der(include_ec_params=False)
result = PKCS8.wrap(private_key,
unrestricted_oid,
key_params=DerObjectId(_curve.oid),
**kwargs)
return result
def _importKeyDER(self, key_data, passphrase=None, params=None):
"""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 = decode_der(DerInteger, key_data).value
params = decode_der(DerSequence, params) # Dss-Parms
p, q, g = list(params)
y = pow(g, x, p)
tup = (y, g, p, q, x)
return self.construct(tup)
der = decode_der(DerSequence, 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 self.construct(tup)
# Try SubjectPublicKeyInfo
if len(der) == 2:
try:
algo = decode_der(DerSequence, der[0])
algo_oid = decode_der(DerObjectId, algo[0]).value
params = decode_der(DerSequence, algo[1]) # Dss-Parms
if algo_oid == oid and len(params) == 3 and\
params.hasOnlyInts():
bitmap = decode_der(DerBitString, der[1])
pub_key = decode_der(DerInteger, bitmap.value)
tup = [pub_key.value]
tup += [params[comp] for comp in (2, 0, 1)]
return self.construct(tup)
except (ValueError, EOFError):
pass
# Try unencrypted PKCS#8
p8_pair = PKCS8.unwrap(key_data, passphrase)
if p8_pair[0] == oid:
return self._importKeyDER(p8_pair[1], passphrase, p8_pair[2])
except (ValueError, EOFError):
pass
raise KeyFormatError("DSA key format is not supported")
def _importKeyDER(self, key_data, passphrase=None, params=None):
"""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 = decode_der(DerInteger, key_data).value
params = decode_der(DerSequence, params) # Dss-Parms
p, q, g = list(params)
y = pow(g, x, p)
tup = (y, g, p, q, x)
return self.construct(tup)
der = decode_der(DerSequence, 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 self.construct(tup)
# Try SubjectPublicKeyInfo
if len(der) == 2:
try:
algo = decode_der(DerSequence, der[0])
algo_oid = decode_der(DerObjectId, algo[0]).value
params = decode_der(DerSequence, algo[1]) # Dss-Parms
if algo_oid == oid and len(params) == 3 and\
params.hasOnlyInts():
bitmap = decode_der(DerBitString, der[1])
pub_key = decode_der(DerInteger, bitmap.value)
tup = [pub_key.value]
tup += [params[comp] for comp in (2, 0, 1)]
return self.construct(tup)
except (ValueError, EOFError):
pass
# Try unencrypted PKCS#8
p8_pair = PKCS8.unwrap(key_data, passphrase)
if p8_pair[0] == oid:
return self._importKeyDER(p8_pair[1], passphrase, p8_pair[2])
except (ValueError, EOFError):
pass
raise KeyFormatError("DSA key format is not supported")
def _parse_key_pkcs8(self, data: bytes) -> bytes:
parsed = pem.parse(data)
if parsed and len(parsed) == 1:
data = base64.b64decode(''.join(
parsed[0].as_text().strip().split("\n")[1:-1]))
try:
(_, key, _) = pkcs8.unwrap(data, self.password.encode("utf-8"))
except ValueError as error:
raise X509AdapterError(
"invalid password or PKCS#8 data") from error
return key
def _load_private_key(self):
"""Load the private key used to sign HTTP requests.
The private key is used to sign HTTP requests as defined in
https://datatracker.ietf.org/doc/draft-cavage-http-signatures/.
"""
if self.private_key is not None:
return
with open(self.private_key_path, 'r') as f:
pem_data = f.read()
# Verify PEM 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")
pem_header = m.group(1)
if pem_header == 'RSA PRIVATE KEY':
self.private_key = RSA.importKey(pem_data,
self.private_key_passphrase)
elif pem_header == 'EC PRIVATE KEY':
self.private_key = ECC.import_key(pem_data,
self.private_key_passphrase)
elif pem_header in {'PRIVATE KEY', 'ENCRYPTED PRIVATE KEY'}:
# Key is in PKCS8 format, which is capable of holding many different
# types of private keys, not just EC keys.
(key_binary, pem_header, is_encrypted) = \
PEM.decode(pem_data, self.private_key_passphrase)
(oid, privkey, params) = \
PKCS8.unwrap(key_binary, passphrase=self.private_key_passphrase)
if oid == '1.2.840.10045.2.1':
self.private_key = ECC.import_key(
pem_data, self.private_key_passphrase)
else:
raise Exception("Unsupported key: {0}. OID: {1}".format(
pem_header, oid))
else:
raise Exception("Unsupported key: {0}".format(pem_header))
# Validate the specified signature algorithm is compatible with the private key.
if self.signing_algorithm is not None:
supported_algs = None
if isinstance(self.private_key, RSA.RsaKey):
supported_algs = {
ALGORITHM_RSASSA_PSS, ALGORITHM_RSASSA_PKCS1v15
}
elif isinstance(self.private_key, ECC.EccKey):
supported_algs = ALGORITHM_ECDSA_KEY_SIGNING_ALGORITHMS
if supported_algs is not None and self.signing_algorithm not in supported_algs:
raise Exception(
"Signing algorithm {0} is not compatible with private key"
.format(self.signing_algorithm))
def _importKeyDER(self, extern_key, passphrase=None):
"""Import an RSA key (public or private half), encoded in DER form."""
try:
der = decode_der(DerSequence, extern_key)
# Try PKCS#1 first, for a private key
if len(der) == 9 and der.hasOnlyInts() and der[0] == 0:
# ASN.1 RSAPrivateKey element
del der[6:] # Remove d mod (p-1),
# d mod (q-1), and
# q^{-1} mod p
der.append(inverse(der[4], der[5])) # Add p^{-1} mod q
del der[0] # Remove version
return self.construct(der[:])
# Keep on trying PKCS#1, but now for a public key
if len(der) == 2:
try:
# The DER object is an RSAPublicKey SEQUENCE with
# two elements
if der.hasOnlyInts():
return self.construct(der[:])
# The DER object is a SubjectPublicKeyInfo SEQUENCE
# with two elements: an 'algorithmIdentifier' and a
# 'subjectPublicKey'BIT STRING.
# 'algorithmIdentifier' takes the value given at the
# module level.
# 'subjectPublicKey' encapsulates the actual ASN.1
# RSAPublicKey element.
if der[0] == algorithmIdentifier:
bitmap = decode_der(DerBitString, der[1])
rsaPub = decode_der(DerSequence, bitmap.value)
if len(rsaPub) == 2 and rsaPub.hasOnlyInts():
return self.construct(rsaPub[:])
except (ValueError, EOFError):
pass
# Try PKCS#8 (possibly encrypted)
k = PKCS8.unwrap(extern_key, passphrase)
if k[0] == oid:
return self._importKeyDER(k[1], passphrase)
except (ValueError, EOFError):
pass
raise ValueError("RSA key format is not supported")
def _importKeyDER(self, extern_key, passphrase=None):
"""Import an RSA key (public or private half), encoded in DER form."""
try:
der = decode_der(DerSequence, extern_key)
# Try PKCS#1 first, for a private key
if len(der) == 9 and der.hasOnlyInts() and der[0] == 0:
# ASN.1 RSAPrivateKey element
del der[6:] # Remove d mod (p-1),
# d mod (q-1), and
# q^{-1} mod p
der.append(inverse(der[4], der[5])) # Add p^{-1} mod q
del der[0] # Remove version
return self.construct(der[:])
# Keep on trying PKCS#1, but now for a public key
if len(der) == 2:
try:
# The DER object is an RSAPublicKey SEQUENCE with
# two elements
if der.hasOnlyInts():
return self.construct(der[:])
# The DER object is a SubjectPublicKeyInfo SEQUENCE
# with two elements: an 'algorithmIdentifier' and a
# 'subjectPublicKey'BIT STRING.
# 'algorithmIdentifier' takes the value given at the
# module level.
# 'subjectPublicKey' encapsulates the actual ASN.1
# RSAPublicKey element.
if der[0] == algorithmIdentifier:
bitmap = decode_der(DerBitString, der[1])
rsaPub = decode_der(DerSequence, bitmap.value)
if len(rsaPub) == 2 and rsaPub.hasOnlyInts():
return self.construct(rsaPub[:])
except (ValueError, EOFError):
pass
# Try PKCS#8 (possibly encrypted)
k = PKCS8.unwrap(extern_key, passphrase)
if k[0] == oid:
return self._importKeyDER(k[1], passphrase)
except (ValueError, EOFError):
pass
raise ValueError("RSA key format is not supported")
def test4(self):
"""Verify wrapping with encryption"""
for t in self.wrapped_enc_keys:
if t[0] == -1:
continue
rng = Rng(t[2] + t[3])
params = {'iteration_count': t[1]}
wrapped = PKCS8.wrap(self.clear_key,
self.oid_key,
b("TestTest"),
protection=t[0],
prot_params=params,
key_params=None,
randfunc=rng)
self.assertEqual(wrapped, t[4])
def test4(self):
"""Verify wrapping with encryption"""
for t in self.wrapped_enc_keys:
if t[0]==-1:
continue
rng = Rng(t[2]+t[3])
params = { 'iteration_count':t[1] }
wrapped = PKCS8.wrap(
self.clear_key,
self.oid_key,
b("TestTest"),
protection=t[0],
prot_params=params,
key_params=None,
randfunc=rng)
self.assertEqual(wrapped, t[4])
def _import_pkcs8(encoded, passphrase):
# From RFC5915, Section 1:
#
# Distributing an EC private key with PKCS#8 [RFC5208] involves including:
# a) id-ecPublicKey, id-ecDH, or id-ecMQV (from [RFC5480]) with the
# namedCurve as the parameters in the privateKeyAlgorithm field; and
# b) ECPrivateKey in the PrivateKey field, which is an OCTET STRING.
algo_oid, private_key, params = PKCS8.unwrap(encoded, passphrase)
# We accept id-ecPublicKey, id-ecDH, id-ecMQV without making any
# distiction for now.
unrestricted_oid = "1.2.840.10045.2.1"
ecdh_oid = "1.3.132.1.12"
ecmqv_oid = "1.3.132.1.13"
if algo_oid not in (unrestricted_oid, ecdh_oid, ecmqv_oid):
raise ValueError("No PKCS#8 encoded ECC key")
curve_name = DerObjectId().decode(params).value
return _import_private_der(private_key, passphrase, curve_name)
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 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 = 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 test2(self):
"""Verify wrapping w/o encryption"""
wrapped = PKCS8.wrap(self.clear_key, self.oid_key)
res1, res2, res3 = PKCS8.unwrap(wrapped)
self.assertEqual(res1, self.oid_key)
self.assertEqual(res2, self.clear_key)
def test1(self):
"""Verify unwrapping w/o encryption"""
res1, res2, res3 = PKCS8.unwrap(self.wrapped_clear_key)
self.assertEqual(res1, self.oid_key)
self.assertEqual(res2, self.clear_key)
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 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 test2(self):
"""Verify wrapping w/o encryption"""
wrapped = PKCS8.wrap(self.clear_key, self.oid_key)
res1, res2, res3 = PKCS8.unwrap(wrapped)
self.assertEqual(res1, self.oid_key)
self.assertEqual(res2, self.clear_key)
def test1(self):
"""Verify unwrapping w/o encryption"""
res1, res2, res3 = PKCS8.unwrap(self.wrapped_clear_key)
self.assertEqual(res1, self.oid_key)
self.assertEqual(res2, self.clear_key)
def exportKey(self,
format='PEM',
passphrase=None,
pkcs=1,
protection=None,
randfunc=None):
"""Export this RSA key.
:Parameters:
format : string
The format to use for wrapping the key:
- *'DER'*. Binary encoding.
- *'PEM'*. Textual encoding, done according to `RFC1421`_/`RFC1423`_.
- *'OpenSSH'*. Textual encoding, done according to OpenSSH specification.
Only suitable for public keys (not private keys).
passphrase : string
For private keys only. The pass phrase used for deriving the encryption
key.
pkcs : integer
For *DER* and *PEM* format only.
The PKCS standard to follow for assembling the components of the key.
You have two choices:
- **1** (default): the public key is embedded into
an X.509 ``SubjectPublicKeyInfo`` DER SEQUENCE.
The private key is embedded into a `PKCS#1`_
``RSAPrivateKey`` DER SEQUENCE.
- **8**: the private key is embedded into a `PKCS#8`_
``PrivateKeyInfo`` DER SEQUENCE. This value cannot be used
for public keys.
protection : string
The encryption scheme to use for protecting the private key.
If ``None`` (default), the behavior depends on ``format``:
- For *DER*, the *PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC*
scheme is used. The following operations are performed:
1. A 16 byte Triple DES key is derived from the passphrase
using `Crypto.Protocol.KDF.PBKDF2` with 8 bytes salt,
and 1 000 iterations of `Crypto.Hash.HMAC`.
2. The private key is encrypted using CBC.
3. The encrypted key is encoded according to PKCS#8.
- For *PEM*, the obsolete PEM encryption scheme is used.
It is based on MD5 for key derivation, and Triple DES for encryption.
Specifying a value for ``protection`` is only meaningful for PKCS#8
(that is, ``pkcs=8``) and only if a pass phrase is present too.
The supported schemes for PKCS#8 are listed in the
`Crypto.IO.PKCS8` module (see ``wrap_algo`` parameter).
randfunc : callable
A function that provides random bytes. Only used for PEM encoding.
The default 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 PKCS#1.
: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
.. _`PKCS#1`: http://www.ietf.org/rfc/rfc3447.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':
eb, nb = [self._key[comp].to_bytes() for comp in 'e', 'n']
if bord(eb[0]) & 0x80: eb = bchr(0x00) + eb
if bord(nb[0]) & 0x80: nb = bchr(0x00) + nb
keyparts = [b('ssh-rsa'), eb, nb]
keystring = b('').join(
[struct.pack(">I", len(kp)) + kp for kp in keyparts])
return b('ssh-rsa ') + binascii.b2a_base64(keystring)[:-1]
# DER format is always used, even in case of PEM, which simply
# encodes it into BASE64.
if self.has_private():
binary_key = newDerSequence(
0, self.n, self.e, self.d, self.p, self.q,
self.d % (self.p - 1), self.d % (self.q - 1),
Integer(self.q).inverse(self.p)).encode()
if pkcs == 1:
keyType = 'RSA PRIVATE'
if format == 'DER' and passphrase:
raise ValueError("PKCS#1 private key cannot be encrypted")
else: # PKCS#8
if format == 'PEM' and protection is None:
keyType = 'PRIVATE'
binary_key = PKCS8.wrap(binary_key, oid, None)
else:
keyType = 'ENCRYPTED PRIVATE'
if not protection:
protection = 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC'
binary_key = PKCS8.wrap(binary_key, oid, passphrase,
protection)
passphrase = None
else:
keyType = "RSA PUBLIC"
binary_key = newDerSequence(
algorithmIdentifier,
newDerBitString(newDerSequence(self.n, self.e))).encode()
if format == 'DER':
return binary_key
if format == 'PEM':
pem_str = PEM.encode(binary_key, keyType + " KEY", passphrase,
randfunc)
return tobytes(pem_str)
raise ValueError(
"Unknown key format '%s'. Cannot export the RSA key." % format)
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 exportKey(self, format='PEM', passphrase=None, pkcs=1, protection=None, randfunc=None):
"""Export this RSA key.
:Parameters:
format : string
The format to use for wrapping the key:
- *'DER'*. Binary encoding.
- *'PEM'*. Textual encoding, done according to `RFC1421`_/`RFC1423`_.
- *'OpenSSH'*. Textual encoding, done according to OpenSSH specification.
Only suitable for public keys (not private keys).
passphrase : string
For private keys only. The pass phrase used for deriving the encryption
key.
pkcs : integer
For *DER* and *PEM* format only.
The PKCS standard to follow for assembling the components of the key.
You have two choices:
- **1** (default): the public key is embedded into
an X.509 ``SubjectPublicKeyInfo`` DER SEQUENCE.
The private key is embedded into a `PKCS#1`_
``RSAPrivateKey`` DER SEQUENCE.
- **8**: the private key is embedded into a `PKCS#8`_
``PrivateKeyInfo`` DER SEQUENCE. This value cannot be used
for public keys.
protection : string
The encryption scheme to use for protecting the private key.
If ``None`` (default), the behavior depends on ``format``:
- For *DER*, the *PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC*
scheme is used. The following operations are performed:
1. A 16 byte Triple DES key is derived from the passphrase
using `Crypto.Protocol.KDF.PBKDF2` with 8 bytes salt,
and 1 000 iterations of `Crypto.Hash.HMAC`.
2. The private key is encrypted using CBC.
3. The encrypted key is encoded according to PKCS#8.
- For *PEM*, the obsolete PEM encryption scheme is used.
It is based on MD5 for key derivation, and Triple DES for encryption.
Specifying a value for ``protection`` is only meaningful for PKCS#8
(that is, ``pkcs=8``) and only if a pass phrase is present too.
The supported schemes for PKCS#8 are listed in the
`Crypto.IO.PKCS8` module (see ``wrap_algo`` parameter).
randfunc : callable
A function that provides random bytes. Only used for PEM encoding.
The default 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 PKCS#1.
: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
.. _`PKCS#1`: http://www.ietf.org/rfc/rfc3447.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':
eb, nb = [self._key[comp].to_bytes() for comp in 'e', 'n']
if bord(eb[0]) & 0x80: eb=bchr(0x00)+eb
if bord(nb[0]) & 0x80: nb=bchr(0x00)+nb
keyparts = [ b('ssh-rsa'), eb, nb ]
keystring = b('').join([ struct.pack(">I",len(kp))+kp for kp in keyparts])
return b('ssh-rsa ')+binascii.b2a_base64(keystring)[:-1]
# DER format is always used, even in case of PEM, which simply
# encodes it into BASE64.
if self.has_private():
binary_key = newDerSequence(
0,
self.n,
self.e,
self.d,
self.p,
self.q,
self.d % (self.p-1),
self.d % (self.q-1),
Integer(self.q).inverse(self.p)
).encode()
if pkcs==1:
keyType = 'RSA PRIVATE'
if format=='DER' and passphrase:
raise ValueError("PKCS#1 private key cannot be encrypted")
else: # PKCS#8
if format=='PEM' and protection is None:
keyType = 'PRIVATE'
binary_key = PKCS8.wrap(binary_key, oid, None)
else:
keyType = 'ENCRYPTED PRIVATE'
if not protection:
protection = 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC'
binary_key = PKCS8.wrap(binary_key, oid, passphrase, protection)
passphrase = None
else:
keyType = "RSA PUBLIC"
binary_key = newDerSequence(
algorithmIdentifier,
newDerBitString(
newDerSequence( self.n, self.e )
)
).encode()
if format=='DER':
return binary_key
if format=='PEM':
pem_str = PEM.encode(binary_key, keyType+" KEY", passphrase, randfunc)
return tobytes(pem_str)
raise ValueError("Unknown key format '%s'. Cannot export the RSA key." % format)
def exportKey(self, format='PEM', passphrase=None, pkcs=1,
protection=None, randfunc=None):
"""Export this RSA key.
Args:
format (string):
The format to use for wrapping the key:
- *'PEM'*. (*Default*) Text encoding, done according to `RFC1421`_/`RFC1423`_.
- *'DER'*. Binary encoding.
- *'OpenSSH'*. Textual encoding, done according to OpenSSH specification.
Only suitable for public keys (not private keys).
passphrase (string):
(*For private keys only*) The pass phrase used for protecting the output.
pkcs (integer):
(*For private keys only*) The ASN.1 structure to use for
serializing the key. Note that even in case of PEM
encoding, there is an inner ASN.1 DER structure.
With ``pkcs=1`` (*default*), the private key is encoded in a
simple `PKCS#1`_ structure (``RSAPrivateKey``).
With ``pkcs=8``, the private key is encoded in a `PKCS#8`_ structure
(``PrivateKeyInfo``).
.. note::
This parameter is ignored for a public key.
For DER and PEM, an ASN.1 DER ``SubjectPublicKeyInfo``
structure is always used.
protection (string):
(*For private keys only*)
The encryption scheme to use for protecting the private key.
If ``None`` (default), the behavior depends on :attr:`format`:
- For *'DER'*, the *PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC*
scheme is used. The following operations are performed:
1. A 16 byte Triple DES key is derived from the passphrase
using :func:`Crypto.Protocol.KDF.PBKDF2` with 8 bytes salt,
and 1 000 iterations of :mod:`Crypto.Hash.HMAC`.
2. The private key is encrypted using CBC.
3. The encrypted key is encoded according to PKCS#8.
- For *'PEM'*, the obsolete PEM encryption scheme is used.
It is based on MD5 for key derivation, and Triple DES for encryption.
Specifying a value for :attr:`protection` is only meaningful for PKCS#8
(that is, ``pkcs=8``) and only if a pass phrase is present too.
The supported schemes for PKCS#8 are listed in the
:mod:`Crypto.IO.PKCS8` module (see :attr:`wrap_algo` parameter).
randfunc (callable):
A function that provides random bytes. Only used for PEM encoding.
The default 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 PKCS#1.
.. 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
.. _`PKCS#1`: http://www.ietf.org/rfc/rfc3447.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':
e_bytes, n_bytes = [x.to_bytes() for x in (self._e, self._n)]
if bord(e_bytes[0]) & 0x80:
e_bytes = bchr(0) + e_bytes
if bord(n_bytes[0]) & 0x80:
n_bytes = bchr(0) + n_bytes
keyparts = [b('ssh-rsa'), e_bytes, n_bytes]
keystring = b('').join([struct.pack(">I", len(kp)) + kp for kp in keyparts])
return b('ssh-rsa ') + binascii.b2a_base64(keystring)[:-1]
# DER format is always used, even in case of PEM, which simply
# encodes it into BASE64.
if self.has_private():
binary_key = DerSequence([0,
self.n,
self.e,
self.d,
self.p,
self.q,
self.d % (self.p-1),
self.d % (self.q-1),
Integer(self.q).inverse(self.p)
]).encode()
if pkcs == 1:
key_type = 'RSA PRIVATE KEY'
if format == 'DER' and passphrase:
raise ValueError("PKCS#1 private key cannot be encrypted")
else: # PKCS#8
if format == 'PEM' and protection is None:
key_type = 'PRIVATE KEY'
binary_key = PKCS8.wrap(binary_key, oid, None)
else:
key_type = 'ENCRYPTED PRIVATE KEY'
if not protection:
protection = 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC'
binary_key = PKCS8.wrap(binary_key, oid,
passphrase, protection)
passphrase = None
else:
key_type = "PUBLIC KEY"
binary_key = _create_subject_public_key_info(oid,
DerSequence([self.n,
self.e])
)
if format == 'DER':
return binary_key
if format == 'PEM':
pem_str = PEM.encode(binary_key, key_type, passphrase, randfunc)
return tobytes(pem_str)
raise ValueError("Unknown key format '%s'. Cannot export the RSA key." % format)
def exportKey(self,
format='PEM',
passphrase=None,
pkcs=1,
protection=None,
randfunc=None):
"""Export this RSA key.
Args:
format (string):
The format to use for wrapping the key:
- *'PEM'*. (*Default*) Text encoding, done according to `RFC1421`_/`RFC1423`_.
- *'DER'*. Binary encoding.
- *'OpenSSH'*. Textual encoding, done according to OpenSSH specification.
Only suitable for public keys (not private keys).
passphrase (string):
(*For private keys only*) The pass phrase used for protecting the output.
pkcs (integer):
(*For private keys only*) The ASN.1 structure to use for
serializing the key. Note that even in case of PEM
encoding, there is an inner ASN.1 DER structure.
With ``pkcs=1`` (*default*), the private key is encoded in a
simple `PKCS#1`_ structure (``RSAPrivateKey``).
With ``pkcs=8``, the private key is encoded in a `PKCS#8`_ structure
(``PrivateKeyInfo``).
.. note::
This parameter is ignored for a public key.
For DER and PEM, an ASN.1 DER ``SubjectPublicKeyInfo``
structure is always used.
protection (string):
(*For private keys only*)
The encryption scheme to use for protecting the private key.
If ``None`` (default), the behavior depends on :attr:`format`:
- For *'DER'*, the *PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC*
scheme is used. The following operations are performed:
1. A 16 byte Triple DES key is derived from the passphrase
using :func:`Crypto.Protocol.KDF.PBKDF2` with 8 bytes salt,
and 1 000 iterations of :mod:`Crypto.Hash.HMAC`.
2. The private key is encrypted using CBC.
3. The encrypted key is encoded according to PKCS#8.
- For *'PEM'*, the obsolete PEM encryption scheme is used.
It is based on MD5 for key derivation, and Triple DES for encryption.
Specifying a value for :attr:`protection` is only meaningful for PKCS#8
(that is, ``pkcs=8``) and only if a pass phrase is present too.
The supported schemes for PKCS#8 are listed in the
:mod:`Crypto.IO.PKCS8` module (see :attr:`wrap_algo` parameter).
randfunc (callable):
A function that provides random bytes. Only used for PEM encoding.
The default 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 PKCS#1.
.. 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
.. _`PKCS#1`: http://www.ietf.org/rfc/rfc3447.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':
e_bytes, n_bytes = [x.to_bytes() for x in (self._e, self._n)]
if bord(e_bytes[0]) & 0x80:
e_bytes = bchr(0) + e_bytes
if bord(n_bytes[0]) & 0x80:
n_bytes = bchr(0) + n_bytes
keyparts = [b('ssh-rsa'), e_bytes, n_bytes]
keystring = b('').join(
[struct.pack(">I", len(kp)) + kp for kp in keyparts])
return b('ssh-rsa ') + binascii.b2a_base64(keystring)[:-1]
# DER format is always used, even in case of PEM, which simply
# encodes it into BASE64.
if self.has_private():
binary_key = DerSequence([
0, self.n, self.e, self.d, self.p, self.q,
self.d % (self.p - 1), self.d % (self.q - 1),
Integer(self.q).inverse(self.p)
]).encode()
if pkcs == 1:
key_type = 'RSA PRIVATE KEY'
if format == 'DER' and passphrase:
raise ValueError("PKCS#1 private key cannot be encrypted")
else: # PKCS#8
if format == 'PEM' and protection is None:
key_type = 'PRIVATE KEY'
binary_key = PKCS8.wrap(binary_key, oid, None)
else:
key_type = 'ENCRYPTED PRIVATE KEY'
if not protection:
protection = 'PBKDF2WithHMAC-SHA1AndDES-EDE3-CBC'
binary_key = PKCS8.wrap(binary_key, oid, passphrase,
protection)
passphrase = None
else:
key_type = "PUBLIC KEY"
binary_key = _create_subject_public_key_info(
oid, DerSequence([self.n, self.e]))
if format == 'DER':
return binary_key
if format == 'PEM':
pem_str = PEM.encode(binary_key, key_type, passphrase, randfunc)
return tobytes(pem_str)
raise ValueError(
"Unknown key format '%s'. Cannot export the RSA key." % format)
def _import_pkcs8(encoded, passphrase):
k = PKCS8.unwrap(encoded, passphrase)
if k[0] != oid:
raise ValueError("No PKCS#8 encoded RSA key")
return _import_keyDER(k[1], passphrase)
