RSA_METHOD now supports key-generation, but (for now) none of these
ENGINEs implement it.

engines/e_4758_cca.c

diff --git a/engines/e_4758_cca.c b/engines/e_4758_cca.c
index 091e2dd..68a6282 100644
--- a/engines/e_4758_cca.c
+++ b/engines/e_4758_cca.c
@@ -182,7 +182,8 @@
 	RSA_FLAG_SIGN_VER,	  /* flags */
 	NULL, /* app_data */
 	cca_rsa_sign, /* rsa_sign */
-	cca_rsa_verify  /* rsa_verify */
+	cca_rsa_verify, /* rsa_verify */
+	NULL /* rsa_keygen */
 	};
 #endif