def _load_pkcs1_der(cls, keyfile):
"""Loads a key in PKCS#1 DER format.
:param keyfile: contents of a DER-encoded file that contains the public
key.
:return: a PublicKey object
First let's construct a DER encoded key:
>>> import base64
>>> b64der = 'MAwCBQCNGmYtAgMBAAE='
>>> der = base64.standard_b64decode(b64der)
This loads the file:
>>> PublicKey._load_pkcs1_der(der)
PublicKey(2367317549, 65537)
"""
# pylint: disable=import-outside-toplevel
from adafruit_rsa.tools.pyasn1.codec.der import decoder
from adafruit_rsa.asn1 import AsnPubKey
(priv, _) = decoder.decode(keyfile, asn1Spec=AsnPubKey())
return cls(n=int(priv["modulus"]), e=int(priv["publicExponent"]))
def _save_pkcs1_der(self):
"""Saves the public key in PKCS#1 DER format.
:returns: the DER-encoded public key.
:rtype: bytes
"""
# pylint: disable=import-outside-toplevel
from pyasn1.codec.der import encoder
from rsa.asn1 import AsnPubKey
# Create the ASN object
asn_key = AsnPubKey()
asn_key.setComponentByName("modulus", self.n)
asn_key.setComponentByName("publicExponent", self.e)
return encoder.encode(asn_key)
def _save_pkcs1_der(self):
"""Saves the public key in PKCS#1 DER format.
:returns: the DER-encoded public key.
:rtype: bytes
"""
from pyasn1.codec.der import encoder
from rsa.asn1 import AsnPubKey
# Create the ASN object
asn_key = AsnPubKey()
asn_key.setComponentByName('modulus', self.n)
asn_key.setComponentByName('publicExponent', self.e)
return encoder.encode(asn_key)