oscrypto/_win/asymmetric.py
def _bcrypt_interpret_rsa_key_blob(key_type, blob_struct, blob):
    """
    Take a CNG BCRYPT_RSAFULLPRIVATE_BLOB and converts it into an ASN.1
    structure

    :param key_type:
        A unicode string of "private" or "public"

    :param blob_struct:
        An instance of BCRYPT_RSAKEY_BLOB

    :param blob:
        A byte string of the binary data contained after the struct

    :return:
        An asn1crypto.keys.PrivateKeyInfo or asn1crypto.keys.PublicKeyInfo
        object, based on the key_type param
    """

    public_exponent_byte_length = native(int, blob_struct.cbPublicExp)
    modulus_byte_length = native(int, blob_struct.cbModulus)

    modulus_offset = public_exponent_byte_length

    public_exponent = int_from_bytes(blob[0:modulus_offset])
    modulus = int_from_bytes(blob[modulus_offset:modulus_offset + modulus_byte_length])

    if key_type == 'public':
        return keys.PublicKeyInfo({
            'algorithm': keys.PublicKeyAlgorithm({
                'algorithm': 'rsa',
            }),
            'public_key': keys.RSAPublicKey({
                'modulus': modulus,
                'public_exponent': public_exponent,
            }),
        })

    elif key_type == 'private':
        prime1_byte_length = native(int, blob_struct.cbPrime1)
        prime2_byte_length = native(int, blob_struct.cbPrime2)

        prime1_offset = modulus_offset + modulus_byte_length
        prime2_offset = prime1_offset + prime1_byte_length
        exponent1_offset = prime2_offset + prime2_byte_length
        exponent2_offset = exponent1_offset + prime2_byte_length
        coefficient_offset = exponent2_offset + prime2_byte_length
        private_exponent_offset = coefficient_offset + prime1_byte_length

        prime1 = int_from_bytes(blob[prime1_offset:prime2_offset])
        prime2 = int_from_bytes(blob[prime2_offset:exponent1_offset])
        exponent1 = int_from_bytes(blob[exponent1_offset:exponent2_offset])
        exponent2 = int_from_bytes(blob[exponent2_offset:coefficient_offset])
        coefficient = int_from_bytes(blob[coefficient_offset:private_exponent_offset])
        private_exponent = int_from_bytes(blob[private_exponent_offset:private_exponent_offset + modulus_byte_length])

        rsa_private_key = keys.RSAPrivateKey({
            'version': 'two-prime',
            'modulus': modulus,
            'public_exponent': public_exponent,
            'private_exponent': private_exponent,
            'prime1': prime1,
            'prime2': prime2,
            'exponent1': exponent1,
            'exponent2': exponent2,
            'coefficient': coefficient,
        })

        return keys.PrivateKeyInfo({
            'version': 0,
            'private_key_algorithm': keys.PrivateKeyAlgorithm({
                'algorithm': 'rsa',
            }),
            'private_key': rsa_private_key,
        })

    else:
        raise ValueError(pretty_message(
            '''
            key_type must be one of "public", "private", not %s
            ''',
            repr(key_type)
        ))
def _bcrypt_interpret_rsa_key_blob(key_type, blob_struct, blob):
    """
    Take a CNG BCRYPT_RSAFULLPRIVATE_BLOB and converts it into an ASN.1
    structure

    :param key_type:
        A unicode string of "private" or "public"

    :param blob_struct:
        An instance of BCRYPT_RSAKEY_BLOB

    :param blob:
        A byte string of the binary data contained after the struct

    :return:
        An asn1crypto.keys.PrivateKeyInfo or asn1crypto.keys.PublicKeyInfo
        object, based on the key_type param
    """

    public_exponent_byte_length = native(int, blob_struct.cbPublicExp)
    modulus_byte_length = native(int, blob_struct.cbModulus)

    modulus_offset = public_exponent_byte_length

    public_exponent = int_from_bytes(blob[0:modulus_offset])
    modulus = int_from_bytes(blob[modulus_offset:modulus_offset + modulus_byte_length])

    if key_type == 'public':
        return keys.PublicKeyInfo({
            'algorithm': keys.PublicKeyAlgorithm({
                'algorithm': 'rsa',
            }),
            'public_key': keys.RSAPublicKey({
                'modulus': modulus,
                'public_exponent': public_exponent,
            }),
        })

    elif key_type == 'private':
        prime1_byte_length = native(int, blob_struct.cbPrime1)
        prime2_byte_length = native(int, blob_struct.cbPrime2)

        prime1_offset = modulus_offset + modulus_byte_length
        prime2_offset = prime1_offset + prime1_byte_length
        exponent1_offset = prime2_offset + prime2_byte_length
        exponent2_offset = exponent1_offset + prime2_byte_length
        coefficient_offset = exponent2_offset + prime2_byte_length
        private_exponent_offset = coefficient_offset + prime1_byte_length

        prime1 = int_from_bytes(blob[prime1_offset:prime2_offset])
        prime2 = int_from_bytes(blob[prime2_offset:exponent1_offset])
        exponent1 = int_from_bytes(blob[exponent1_offset:exponent2_offset])
        exponent2 = int_from_bytes(blob[exponent2_offset:coefficient_offset])
        coefficient = int_from_bytes(blob[coefficient_offset:private_exponent_offset])
        private_exponent = int_from_bytes(blob[private_exponent_offset:private_exponent_offset + modulus_byte_length])

        rsa_private_key = keys.RSAPrivateKey({
            'version': 'two-prime',
            'modulus': modulus,
            'public_exponent': public_exponent,
            'private_exponent': private_exponent,
            'prime1': prime1,
            'prime2': prime2,
            'exponent1': exponent1,
            'exponent2': exponent2,
            'coefficient': coefficient,
        })

        return keys.PrivateKeyInfo({
            'version': 0,
            'private_key_algorithm': keys.PrivateKeyAlgorithm({
                'algorithm': 'rsa',
            }),
            'private_key': rsa_private_key,
        })

    else:
        raise ValueError(pretty_message(
            '''
            key_type must be one of "public", "private", not %s
            ''',
            repr(key_type)
        ))
def _bcrypt_interpret_rsa_key_blob ( key_type , blob_struct , blob ) : public_exponent_byte_length = native ( int , blob_struct . cbPublicExp ) modulus_byte_length = native ( int , blob_struct . cbModulus ) modulus_offset = public_exponent_byte_length public_exponent = int_from_bytes ( blob [ 0 : modulus_offset ] ) modulus = int_from_bytes ( blob [ modulus_offset : modulus_offset + modulus_byte_length ] ) if key_type == 'public' : return keys . PublicKeyInfo ( { 'algorithm' : keys . PublicKeyAlgorithm ( { 'algorithm' : 'rsa' , } ) , 'public_key' : keys . RSAPublicKey ( { 'modulus' : modulus , 'public_exponent' : public_exponent , } ) , } ) elif key_type == 'private' : prime1_byte_length = native ( int , blob_struct . cbPrime1 ) prime2_byte_length = native ( int , blob_struct . cbPrime2 ) prime1_offset = modulus_offset + modulus_byte_length prime2_offset = prime1_offset + prime1_byte_length exponent1_offset = prime2_offset + prime2_byte_length exponent2_offset = exponent1_offset + prime2_byte_length coefficient_offset = exponent2_offset + prime2_byte_length private_exponent_offset = coefficient_offset + prime1_byte_length prime1 = int_from_bytes ( blob [ prime1_offset : prime2_offset ] ) prime2 = int_from_bytes ( blob [ prime2_offset : exponent1_offset ] ) exponent1 = int_from_bytes ( blob [ exponent1_offset : exponent2_offset ] ) exponent2 = int_from_bytes ( blob [ exponent2_offset : coefficient_offset ] ) coefficient = int_from_bytes ( blob [ coefficient_offset : private_exponent_offset ] ) private_exponent = int_from_bytes ( blob [ private_exponent_offset : private_exponent_offset + modulus_byte_length ] ) rsa_private_key = keys . RSAPrivateKey ( { 'version' : 'two-prime' , 'modulus' : modulus , 'public_exponent' : public_exponent , 'private_exponent' : private_exponent , 'prime1' : prime1 , 'prime2' : prime2 , 'exponent1' : exponent1 , 'exponent2' : exponent2 , 'coefficient' : coefficient , } ) return keys . PrivateKeyInfo ( { 'version' : 0 , 'private_key_algorithm' : keys . PrivateKeyAlgorithm ( { 'algorithm' : 'rsa' , } ) , 'private_key' : rsa_private_key , } ) else : raise ValueError ( pretty_message ( '''
            key_type must be one of "public", "private", not %s
            ''' , repr ( key_type ) ) )
Take a CNG BCRYPT_RSAFULLPRIVATE_BLOB and converts it into an ASN.1
    structure

    :param key_type:
        A unicode string of "private" or "public"

    :param blob_struct:
        An instance of BCRYPT_RSAKEY_BLOB

    :param blob:
        A byte string of the binary data contained after the struct

    :return:
        An asn1crypto.keys.PrivateKeyInfo or asn1crypto.keys.PublicKeyInfo
        object, based on the key_type param
Take a CNG BCRYPT_RSAFULLPRIVATE_BLOB and converts it into an ASN . 1 structure