crypto.py 文件源码

def __sign_content(self, content, user_sk):
        """ Produce a signature of an input content using RSASSA-PSS scheme

        @developer: vsmysle

        :param content: bytes content to sign
        :param user_sk: instance of cryptography.hazmat.primitives.rsa.
                        RSAPrivateKey

        :return: bytes of signature of the input content

        """

        # TODO: add exceptions

        self.logger.debug("generating a signature of an input content")
        # creating signer that will sign our content
        try:
            signer = user_sk.signer(
                # we use RSASSA-PSS padding for the signature scheme
                asym_padding.PSS(
                    mgf=asym_padding.MGF1(SHA1()),
                    salt_length=asym_padding.PSS.MAX_LENGTH
                ),
                SHA1()
            )
        except InvalidKey:
            self.logger.warning("Invalid key!")
            return
        signer.update(content)
        signature = signer.finalize()
        self.logger.info("signature generation finished")
        return signature