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 _load_pkcs1_der(cls, keyfile):
"""Loads a key in PKCS#1 DER format.
:param keyfile: contents of a DER-encoded file that contains the private
key.
:type keyfile: bytes
:return: a PrivateKey object
First let's construct a DER encoded key:
>>> import base64
>>> b64der = 'MC4CAQACBQDeKYlRAgMBAAECBQDHn4npAgMA/icCAwDfxwIDANcXAgInbwIDAMZt'
>>> der = base64.standard_b64decode(b64der)
This loads the file:
>>> PrivateKey._load_pkcs1_der(der)
PrivateKey(3727264081, 65537, 3349121513, 65063, 57287)
"""
from adafruit_rsa.tools.pyasn1.codec.der import ( # pylint: disable=import-outside-toplevel
decoder,
)
(priv, _) = decoder.decode(keyfile)
# ASN.1 contents of DER encoded private key:
#
# RSAPrivateKey ::= SEQUENCE {
# version Version,
# modulus INTEGER, -- n
# publicExponent INTEGER, -- e
# privateExponent INTEGER, -- d
# prime1 INTEGER, -- p
# prime2 INTEGER, -- q
# exponent1 INTEGER, -- d mod (p-1)
# exponent2 INTEGER, -- d mod (q-1)
# coefficient INTEGER, -- (inverse of q) mod p
# otherPrimeInfos OtherPrimeInfos OPTIONAL
# }
if priv[0] != 0:
raise ValueError("Unable to read this file, version %s != 0" % priv[0])
as_ints = map(int, priv[1:6])
key = cls(*as_ints)
exp1, exp2, coef = map(int, priv[6:9])
if (key.exp1, key.exp2, key.coef) != (exp1, exp2, coef):
log.debug(
"You have providied a malformed keyfile. Either the exponents"
"or the coefficient are incorrect."
)
return key
def load_pkcs1_openssl_der(cls, keyfile):
"""Loads a PKCS#1 DER-encoded public key file from OpenSSL.
:param keyfile: contents of a DER-encoded file that contains the public
key, from OpenSSL.
:return: a PublicKey object
:rtype: bytes
"""
# pylint: disable=import-outside-toplevel
from adafruit_rsa.asn1 import OpenSSLPubKey
from pyasn1.codec.der import decoder
from pyasn1.type import univ
(keyinfo, _) = decoder.decode(keyfile, asn1Spec=OpenSSLPubKey())
if keyinfo["header"]["oid"] != univ.ObjectIdentifier("1.2.840.113549.1.1.1"):
raise TypeError("This is not a DER-encoded OpenSSL-compatible public key")
return cls._load_pkcs1_der(keyinfo["key"][1:])