5 files changed, 23 insertions, 2 deletions
diff --git a/src/cryptography/hazmat/backends/interfaces.py b/src/cryptography/hazmat/backends/interfaces.py
index eca7ddf4..512cb6e3 100644
--- a/src/cryptography/hazmat/backends/interfaces.py
+++ b/src/cryptography/hazmat/backends/interfaces.py
@@ -274,6 +274,12 @@ class X509Backend(object):
         Load an X.509 CSR from PEM encoded data.
         """
 
+    @abc.abstractmethod
+    def create_x509_csr(self, builder, private_key, algorithm):
+        """
+        Create and sign an X.509 CSR from a CSR buidler object.
+        """
+
 
 @six.add_metaclass(abc.ABCMeta)
 class DHBackend(object):
diff --git a/src/cryptography/hazmat/backends/multibackend.py b/src/cryptography/hazmat/backends/multibackend.py
index 784ab84d..6e911fd5 100644
--- a/src/cryptography/hazmat/backends/multibackend.py
+++ b/src/cryptography/hazmat/backends/multibackend.py
@@ -342,3 +342,12 @@ class MultiBackend(object):
             "This backend does not support X.509.",
             _Reasons.UNSUPPORTED_X509
         )
+
+    def create_x509_csr(self, builder, private_key, algorithm):
+        for b in self._filtered_backends(X509Backend):
+            return b.create_x509_csr(builder, private_key, algorithm)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support X.509.",
+            _Reasons.UNSUPPORTED_X509
+        )
diff --git a/src/cryptography/hazmat/backends/openssl/backend.py b/src/cryptography/hazmat/backends/openssl/backend.py
index bf838ead..b8b2ab6b 100644
--- a/src/cryptography/hazmat/backends/openssl/backend.py
+++ b/src/cryptography/hazmat/backends/openssl/backend.py
@@ -784,7 +784,7 @@ class Backend(object):
     def create_cmac_ctx(self, algorithm):
         return _CMACContext(self, algorithm)
 
-    def sign_x509_request(self, builder, private_key, algorithm):
+    def create_x509_csr(self, builder, private_key, algorithm):
         # TODO: check type of private key parameter.
         if not isinstance(algorithm, hashes.HashAlgorithm):
             raise TypeError('Algorithm must be a registered hash algorithm.')
diff --git a/src/cryptography/x509.py b/src/cryptography/x509.py
index 012c13ba..2ee1c3ef 100644
--- a/src/cryptography/x509.py
+++ b/src/cryptography/x509.py
@@ -1484,4 +1484,4 @@ class CertificateSigningRequestBuilder(object):
         """
         Signs the request using the requestor's private key.
         """
-        return backend.sign_x509_request(self, private_key, algorithm)
+        return backend.create_x509_csr(self, private_key, algorithm)
diff --git a/tests/hazmat/backends/test_multibackend.py b/tests/hazmat/backends/test_multibackend.py
index 5871e6c8..3c05cdfa 100644
--- a/tests/hazmat/backends/test_multibackend.py
+++ b/tests/hazmat/backends/test_multibackend.py
@@ -203,6 +203,9 @@ class DummyX509Backend(object):
     def load_der_x509_csr(self, data):
         pass
 
+    def create_x509_csr(self, builder, private_key, algorithm):
+        pass
+
 
 class TestMultiBackend(object):
     def test_ciphers(self):
@@ -480,6 +483,7 @@ class TestMultiBackend(object):
         backend.load_der_x509_certificate(b"certdata")
         backend.load_pem_x509_csr(b"reqdata")
         backend.load_der_x509_csr(b"reqdata")
+        backend.create_x509_csr(object(), b"privatekey", hashes.SHA1())
 
         backend = MultiBackend([])
         with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_X509):
@@ -490,3 +494,5 @@ class TestMultiBackend(object):
             backend.load_pem_x509_csr(b"reqdata")
         with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_X509):
             backend.load_der_x509_csr(b"reqdata")
+        with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_X509):
+            backend.create_x509_csr(object(), b"privatekey", hashes.SHA1())