typedef struct transform_inst_if *transform_createinstance_fn(void *st);
typedef bool_t transform_setkey_fn(void *st, uint8_t *key, int32_t keylen);
+typedef bool_t transform_valid_fn(void *st); /* 0: no key; 1: ok */
typedef void transform_delkey_fn(void *st);
typedef void transform_destroyinstance_fn(void *st);
/* Returns:
struct transform_inst_if {
void *st;
transform_setkey_fn *setkey;
+ transform_valid_fn *valid;
transform_delkey_fn *delkey;
transform_apply_fn *forwards;
transform_apply_fn *reverse;