Merge pull request #2565 from reaperhulk/crl-interface

add create_x509_crl interface
diff --git a/docs/hazmat/backends/interfaces.rst b/docs/hazmat/backends/interfaces.rst
index 13f2f42..3a7224f 100644
--- a/docs/hazmat/backends/interfaces.rst
+++ b/docs/hazmat/backends/interfaces.rst
@@ -547,8 +547,8 @@
             :class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm`
             that will be used to generate the request signature.
 
-        :returns: A new object with the
-            :class:`~cryptography.x509.CertificateSigningRequest` interface.
+        :returns: A new instance of
+            :class:`~cryptography.x509.CertificateSigningRequest`.
 
     .. method:: create_x509_certificate(builder, private_key, algorithm)
 
@@ -567,8 +567,7 @@
             :class:`~cryptography.hazmat.primitives.hashes.HashAlgorithm`
             that will be used to generate the certificate signature.
 
-        :returns: A new object with the
-            :class:`~cryptography.x509.Certificate` interface.
+        :returns: A new instance of :class:`~cryptography.x509.Certificate`.
 
     .. method:: create_x509_crl(builder, private_key, algorithm)
 
diff --git a/src/_cffi_src/openssl/pem.py b/src/_cffi_src/openssl/pem.py
index 846e64e..4eb6bb4 100644
--- a/src/_cffi_src/openssl/pem.py
+++ b/src/_cffi_src/openssl/pem.py
@@ -79,6 +79,7 @@
 int PEM_write_bio_ECPrivateKey(BIO *, EC_KEY *, const EVP_CIPHER *,
                                unsigned char *, int, pem_password_cb *,
                                void *);
+int PEM_write_bio_DHparams(BIO *, DH *);
 """
 
 CUSTOMIZATIONS = """