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  3. cryptography.x509._SIG_OIDS_TO_HASH

Python cryptography.x509 模块，_SIG_OIDS_TO_HASH 实例源码

我们从Python开源项目中，提取了以下45个代码示例，用于说明如何使用cryptography.x509._SIG_OIDS_TO_HASH。

项目：noc-orchestrator    作者：DirceuSilvaLabs    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：noc-orchestrator    作者：DirceuSilvaLabs    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：noc-orchestrator    作者：DirceuSilvaLabs    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_REQ_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_req
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：noc-orchestrator    作者：DirceuSilvaLabs    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：noc-orchestrator    作者：DirceuSilvaLabs    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：aws-cfn-plex    作者：lordmuffin    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self.signature_algorithm_oid
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：aws-cfn-plex    作者：lordmuffin    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self.signature_algorithm_oid
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：aws-cfn-plex    作者：lordmuffin    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self.signature_algorithm_oid
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Intranet-Penetration    作者：yuxiaokui    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Intranet-Penetration    作者：yuxiaokui    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Intranet-Penetration    作者：yuxiaokui    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_REQ_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_req
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Intranet-Penetration    作者：yuxiaokui    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Intranet-Penetration    作者：yuxiaokui    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Intranet-Penetration    作者：yuxiaokui    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self._obj2txt(self._x509.sig_alg.algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：MKFQ    作者：maojingios    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：MKFQ    作者：maojingios    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：MKFQ    作者：maojingios    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_REQ_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_req
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：MKFQ    作者：maojingios    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：MKFQ    作者：maojingios    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：MKFQ    作者：maojingios    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self._obj2txt(self._x509.sig_alg.algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：OneClickDTU    作者：satwikkansal    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = _obj2txt(self._backend, self._x509.sig_alg.algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：OneClickDTU    作者：satwikkansal    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = _obj2txt(self._backend, self._x509_crl.sig_alg.algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：OneClickDTU    作者：satwikkansal    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = _obj2txt(self._backend, self._x509_req.sig_alg.algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：xxNet    作者：drzorm    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：xxNet    作者：drzorm    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：xxNet    作者：drzorm    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_REQ_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_req
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：xxNet    作者：drzorm    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：xxNet    作者：drzorm    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：xxNet    作者：drzorm    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self._obj2txt(self._x509.sig_alg.algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：slack_scholar    作者：xLeitix    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：slack_scholar    作者：xLeitix    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：slack_scholar    作者：xLeitix    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_REQ_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_req
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：RemoteTree    作者：deNULL    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self.signature_algorithm_oid
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：RemoteTree    作者：deNULL    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self.signature_algorithm_oid
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：RemoteTree    作者：deNULL    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self.signature_algorithm_oid
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：quickstart-git2s3    作者：aws-quickstart    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self.signature_algorithm_oid
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：quickstart-git2s3    作者：aws-quickstart    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self.signature_algorithm_oid
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：quickstart-git2s3    作者：aws-quickstart    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self.signature_algorithm_oid
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Docker-XX-Net    作者：kuanghy    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Docker-XX-Net    作者：kuanghy    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Docker-XX-Net    作者：kuanghy    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_REQ_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_req
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：Docker-XX-Net    作者：kuanghy    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        oid = self._obj2txt(self._x509.sig_alg.algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：PyQYT    作者：collinsctk    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_get0_signature(
            self._backend._ffi.NULL, alg, self._x509
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：PyQYT    作者：collinsctk    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_CRL_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_crl
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )
项目：PyQYT    作者：collinsctk    | 项目源码 | 文件源码 
def signature_hash_algorithm(self):
        alg = self._backend._ffi.new("X509_ALGOR **")
        self._backend._lib.X509_REQ_get0_signature(
            self._backend._ffi.NULL, alg, self._x509_req
        )
        self._backend.openssl_assert(alg[0] != self._backend._ffi.NULL)
        oid = _obj2txt(self._backend, alg[0].algorithm)
        try:
            return x509._SIG_OIDS_TO_HASH[oid]
        except KeyError:
            raise UnsupportedAlgorithm(
                "Signature algorithm OID:{0} not recognized".format(oid)
            )