def _get_private_key(private_key_pkcs8_text):
"""Get an RSA private key object from a pkcs8 representation."""
der = rsa.pem.load_pem(private_key_pkcs8_text, 'PRIVATE KEY')
asn1_private_key, _ = decoder.decode(der, asn1Spec=PrivateKeyInfo())
return rsa.PrivateKey.load_pkcs1(
asn1_private_key.getComponentByName('privateKey').asOctets(),
format='DER')
def _pkcs8_extract_pubkey(der_form):
try:
pkcs8 = der_decoder.decode(der_form, asn1Spec=PrivateKeyInfo())[0]
pkcs8_key_algo = der_decoder.decode(pkcs8['privateKeyAlgorithm']['parameters'])[0]
except PyAsn1Error as asn1_err:
return None, None
pubkey, key_algo = _x9_62_extract_pubkey(pkcs8['privateKey'])
if key_algo is None:
# Try to fall back to a PKCS8-extracted value:
key_algo = pkcs8_key_algo
return pubkey, key_algo
_PKCS12_ERROR = r"""\
PKCS12 format is not supported by the RSA library.
Either install PyOpenSSL, or please convert .p12 format
to .pem format:
$ cat key.p12 | \
> openssl pkcs12 -nodes -nocerts -passin pass:notasecret | \
> openssl rsa > key.pem
"""
_POW2 = (128, 64, 32, 16, 8, 4, 2, 1)
_PKCS1_MARKER = ('-----BEGIN RSA PRIVATE KEY-----',
'-----END RSA PRIVATE KEY-----')
_PKCS8_MARKER = ('-----BEGIN PRIVATE KEY-----',
'-----END PRIVATE KEY-----')
_PKCS8_SPEC = PrivateKeyInfo()
def _bit_list_to_bytes(bit_list):
"""Converts an iterable of 1's and 0's to bytes.
Combines the list 8 at a time, treating each group of 8 bits
as a single byte.
"""
num_bits = len(bit_list)
byte_vals = bytearray()
for start in six.moves.xrange(0, num_bits, 8):
curr_bits = bit_list[start:start + 8]
char_val = sum(val * digit
for val, digit in zip(_POW2, curr_bits))
byte_vals.append(char_val)