Avoided unnecessary memory copying.

diff --git a/lib/layer/cookiemonster.c b/lib/layer/cookiemonster.c
index 3bed790acd5ec226d75253600993ae37d12be3e8..16f50a1e978c6ddfa2ae5d8225dd1a50f75520b1 100644 (file)
--- a/lib/layer/cookiemonster.c
+++ b/lib/layer/cookiemonster.c
@@ -169,34 +169,29 @@ static int srvr_sockaddr_cc_check(const struct sockaddr **sockaddr,
 
 /**
  * Obtain cookie from cache.
- * @note The ttl and current time are respected. Outdated entries are ignored.
+ * @note Cookies with invalid length are ignored.
  * @param cache cache context
  * @param sa key value
  * @param cookie_opt entire EDNS cookie option (including header)
  * @return true if a cookie exists in cache
  */
-static bool materialise_cookie_opt(kr_cookie_lru_t *cache,
-                                   const struct sockaddr *sa,
-                                   uint8_t cookie_opt[KR_COOKIE_OPT_MAX_LEN])
+static const uint8_t *get_cookie_opt(kr_cookie_lru_t *cache,
+                                     const struct sockaddr *sa)
 {
        assert(cache && sa);
 
        const uint8_t *cached_cookie_opt = kr_cookie_lru_get(cache, sa);
        if (!cached_cookie_opt) {
-               return false;
+               return NULL;
        }
 
        size_t cookie_opt_size = KNOT_EDNS_OPTION_HDRLEN +
                                 knot_edns_opt_get_length(cached_cookie_opt);
        if (cookie_opt_size > KR_COOKIE_OPT_MAX_LEN) {
-               return false;
-       }
-
-       if (cookie_opt) {
-               memcpy(cookie_opt, cached_cookie_opt, cookie_opt_size);
+               return NULL;
        }
 
-       return true;
+       return cached_cookie_opt;
 }
 
 /**
@@ -210,10 +205,8 @@ static bool is_cookie_cached(kr_cookie_lru_t *cache, const struct sockaddr *sa,
 {
        assert(cache && sa && cookie_opt);
 
-       uint8_t cached_opt[KR_COOKIE_OPT_MAX_LEN];
-
-       bool have_cached = materialise_cookie_opt(cache, sa, cached_opt);
-       if (!have_cached) {
+       const uint8_t *cached_opt = get_cookie_opt(cache, sa);
+       if (!cached_opt) {
                return false;
        }
 
@@ -304,7 +297,7 @@ static int check_response(knot_layer_t *ctx, knot_pkt_t *pkt)
        const struct sockaddr *srvr_sockaddr = passed_server_sockaddr(qry);
 
        if (!pkt_cookie_opt && srvr_sockaddr &&
-           materialise_cookie_opt(cookie_cache, srvr_sockaddr, NULL)) {
+           get_cookie_opt(cookie_cache, srvr_sockaddr)) {
                /* We haven't received any cookies although we should. */
                DEBUG_MSG(NULL, "%s\n",
                          "expected to receive a cookie but none received");