Add client cert engine to SSL routines.
diff --git a/ssl/ssl_locl.h b/ssl/ssl_locl.h
index a65071a..55b2330 100644
--- a/ssl/ssl_locl.h
+++ b/ssl/ssl_locl.h
@@ -927,6 +927,7 @@
 int ssl3_get_server_done(SSL *s);
 int ssl3_send_client_verify(SSL *s);
 int ssl3_send_client_certificate(SSL *s);
+int ssl_do_client_cert_cb(SSL *s, X509 **px509, EVP_PKEY **ppkey);
 int ssl3_send_client_key_exchange(SSL *s);
 int ssl3_get_key_exchange(SSL *s);
 int ssl3_get_server_certificate(SSL *s);