diff --git a/src/_cffi_src/openssl/ssl.py b/src/_cffi_src/openssl/ssl.py
index 3e1b09209e3b..6942b5fb6f48 100644
--- a/src/_cffi_src/openssl/ssl.py
+++ b/src/_cffi_src/openssl/ssl.py
@@ -253,6 +253,7 @@
                                    unsigned int);
 
 X509_STORE *SSL_CTX_get_cert_store(const SSL_CTX *);
+void SSL_CTX_set_cert_store(SSL_CTX *, X509_STORE *);
 int SSL_CTX_add_client_CA(SSL_CTX *, X509 *);
 
 void SSL_CTX_set_client_CA_list(SSL_CTX *, Cryptography_STACK_OF_X509_NAME *);