bugfixes in tcp connection error handling

diff --git a/daemon/session.c b/daemon/session.c
index c96a783974e90e203dbb7561ac8ecd596869db91..1975258a9ab873782e3b0110c1af3092f750c4f3 100644 (file)
--- a/daemon/session.c
+++ b/daemon/session.c
@@ -398,7 +398,7 @@ void session_waitinglist_retry(struct session *session, bool increase_timeout_cn
                if (increase_timeout_cnt) {
                        worker_task_timeout_inc(task);
                }
-               worker_task_step(task, NULL, NULL);
+               worker_task_step(task, &session->peer.ip, NULL);
                worker_task_unref(task);
        }
 }

diff --git a/daemon/worker.c b/daemon/worker.c
index 5c153811e2bc00eed8bb619c4758a923e91299c0..81856fa93cdfc66192aa0ff713cdd792ffd94d6d 100644 (file)
--- a/daemon/worker.c
+++ b/daemon/worker.c
@@ -794,6 +794,10 @@ static void on_connect(uv_connect_t *req, int status)
        assert(session_flags(session)->outgoing);
 
        if (status == UV_ECANCELED) {
+               if (kr_verbose_status) {
+                       const char *peer_str = kr_straddr(peer);
+                       kr_log_verbose( "[wrkr]=> connect to '%s' cancelled\n", peer_str ? peer_str : "");
+               }
                worker_del_tcp_waiting(worker, peer);
                assert(session_is_empty(session) && session_flags(session)->closing);
                return;
@@ -806,6 +810,11 @@ static void on_connect(uv_connect_t *req, int status)
        }
 
        if (status != 0) {
+               if (kr_verbose_status) {
+                       const char *peer_str = kr_straddr(peer);
+                       kr_log_verbose( "[wrkr]=> connect to '%s' failed (%s)\n",
+                                       peer_str ? peer_str : "", uv_strerror(status));
+               }
                worker_del_tcp_waiting(worker, peer);
                assert(session_tasklist_is_empty(session));
                session_waitinglist_retry(session, false);
@@ -826,13 +835,9 @@ static void on_connect(uv_connect_t *req, int status)
                }
        }
 
-       struct qr_task *task = session_waitinglist_get(session);
-       struct kr_query *qry = task_get_last_pending_query(task);
-       WITH_VERBOSE (qry) {
-               struct sockaddr *peer = session_get_peer(session);
-               char peer_str[INET6_ADDRSTRLEN];
-               inet_ntop(peer->sa_family, kr_inaddr(peer), peer_str, sizeof(peer_str));
-               VERBOSE_MSG(qry, "=> connected to '%s'\n", peer_str);
+       if (kr_verbose_status) {
+               const char *peer_str = kr_straddr(peer);
+               kr_log_verbose( "[wrkr]=> connected to '%s'\n", peer_str ? peer_str : "");
        }
 
        session_flags(session)->connected = true;
@@ -1300,8 +1305,8 @@ static int tcp_task_step(struct qr_task *task,
 {
        assert(task->pending_count == 0);
 
-       const struct sockaddr *addr =
-               packet_source ? packet_source : task->addrlist;
+       /* target */
+       const struct sockaddr *addr = task->addrlist;
        if (addr->sa_family == AF_UNSPEC) {
                /* Target isn't defined. Finalize task with SERVFAIL.
                 * Although task->pending_count is zero, there are can be followers,

diff --git a/lib/nsrep.c b/lib/nsrep.c
index 57747dd3222f6f9e6a05e1c35b06f69a04b04a4d..47f6ac9ae58315c5716158288baafde03f2efa25 100644 (file)
--- a/lib/nsrep.c
+++ b/lib/nsrep.c
@@ -474,13 +474,18 @@ int kr_nsrep_copy_set(struct kr_nsrep *dst, const struct kr_nsrep *src)
        return kr_ok();
 }
 
-int kr_nsrep_sort(struct kr_nsrep *ns, kr_nsrep_rtt_lru_t *rtt_cache)
+int kr_nsrep_sort(struct kr_nsrep *ns, struct kr_context *ctx)
 {
-       if (!ns || !rtt_cache) {
+       if (!ns || !ctx) {
                assert(false);
                return kr_error(EINVAL);
        }
 
+       kr_nsrep_rtt_lru_t *rtt_cache = ctx->cache_rtt;
+
+       ns->reputation = 0;
+       ns->score = KR_NS_MAX_SCORE + 1;
+
        if (ns->addr[0].ip.sa_family == AF_UNSPEC) {
                return kr_error(EINVAL);
        }
@@ -489,6 +494,7 @@ int kr_nsrep_sort(struct kr_nsrep *ns, kr_nsrep_rtt_lru_t *rtt_cache)
         * along the addresses. */
        unsigned scores[KR_NSREP_MAXADDR];
        int i;
+       bool timeouted_address_is_already_selected = false;
        for (i = 0; i < KR_NSREP_MAXADDR; ++i) {
                const struct sockaddr *sa = &ns->addr[i].ip;
                if (sa->sa_family == AF_UNSPEC) {
@@ -499,10 +505,23 @@ int kr_nsrep_sort(struct kr_nsrep *ns, kr_nsrep_rtt_lru_t *rtt_cache)
                                                                        kr_family_len(sa->sa_family));
                if (!rtt_cache_entry) {
                        scores[i] = 1; /* prefer unknown to probe RTT */
-               } else if ((kr_rand_uint(100) < 10) &&
-                          (kr_rand_uint(KR_NS_MAX_SCORE) >= rtt_cache_entry->score)) {
-                       /* some probability to bump bad ones up for re-probe */
-                       scores[i] = 1;
+                       if (sa->sa_family == AF_INET) {
+                               scores[i] += FAVOUR_IPV6;
+                       }
+               } else if (rtt_cache_entry->score >= KR_NS_TIMEOUT) {
+                       uint64_t now = kr_now();
+                       uint64_t elapsed = now - rtt_cache_entry->tout_timestamp;
+                       scores[i] = KR_NS_MAX_SCORE + 1;
+                       elapsed = elapsed > UINT_MAX ? UINT_MAX : elapsed;
+                       if (elapsed > ctx->cache_rtt_tout_retry_interval &&
+                           !timeouted_address_is_already_selected) {
+                               scores[i] = 1;
+                               if (sa->sa_family == AF_INET) {
+                                       scores[i] += FAVOUR_IPV6;
+                               }
+                               rtt_cache_entry->tout_timestamp = now;
+                               timeouted_address_is_already_selected = true;
+                       }
                } else {
                        scores[i] = rtt_cache_entry->score;
                        if (sa->sa_family == AF_INET) {
@@ -510,10 +529,8 @@ int kr_nsrep_sort(struct kr_nsrep *ns, kr_nsrep_rtt_lru_t *rtt_cache)
                        }
                }
                if (VERBOSE_STATUS) {
-                       char sa_str[INET6_ADDRSTRLEN];
-                       inet_ntop(sa->sa_family, kr_inaddr(sa), sa_str, sizeof(sa_str));
                        kr_log_verbose("[     ][nsre] score %d for %s;\t cached RTT: %d\n",
-                                       scores[i], sa_str,
+                                       scores[i], kr_straddr(sa),
                                        rtt_cache_entry ? rtt_cache_entry->score : -1);
                }
        }
@@ -535,9 +552,10 @@ int kr_nsrep_sort(struct kr_nsrep *ns, kr_nsrep_rtt_lru_t *rtt_cache)
                }
        }
 
-       /* At least two addresses must be in the address list */
-       assert(count > 0);
-       ns->score = scores[0];
-       ns->reputation = 0;
+       if (count > 0) {
+               ns->score = scores[0];
+               ns->reputation = 0;
+       }
+
        return kr_ok();
 }

diff --git a/lib/nsrep.h b/lib/nsrep.h
index 15af9fa0878a330c1a3fc2142b8bc3db7e65d7f5..0318de844c82cb79c0eda6e24b07ea3a79f3a58a 100644 (file)
--- a/lib/nsrep.h
+++ b/lib/nsrep.h
@@ -174,12 +174,14 @@ int kr_nsrep_update_rep(struct kr_nsrep *ns, unsigned reputation, kr_nsrep_lru_t
 int kr_nsrep_copy_set(struct kr_nsrep *dst, const struct kr_nsrep *src);
 
 /**
- * Sort addresses in the query nsrep list
+ * Sort addresses in the query nsrep list by cached RTT.
+ * if RTT is greater then KR_NS_TIMEOUT, address will placed at the beginning of the
+ * nsrep list once in cache.ns_tout() milliseconds. Otherwise it will be sorted
+ * as if it has cached RTT equal to KR_NS_MAX_SCORE + 1.
  * @param  ns           updated kr_nsrep
- * @param  rtt_cache    RTT LRU cache
+ * @param  ctx          name resolution context.
  * @return              0 or an error code
- * @note   ns reputation is zeroed, as KR_NS_NOIP{4,6} flags are useless
- *        in STUB/FORWARD mode.
+ * @note   ns reputation is zeroed and score is set to KR_NS_MAX_SCORE + 1.
  */
 KR_EXPORT
-int kr_nsrep_sort(struct kr_nsrep *ns, kr_nsrep_rtt_lru_t *rtt_cache);
+int kr_nsrep_sort(struct kr_nsrep *ns,  struct kr_context *ctx);

diff --git a/lib/resolve.c b/lib/resolve.c
index 40099367756ef39ef165fa72a14767257142bd82..22d64fdeec52215b1d12fd4568d4ac1799527cac 100644 (file)
--- a/lib/resolve.c
+++ b/lib/resolve.c
@@ -1423,12 +1423,14 @@ ns_election:
 
        const struct kr_qflags qflg = qry->flags;
        const bool retry = qflg.TCP || qflg.BADCOOKIE_AGAIN;
-       bool check_timeouted = false;
        if (qflg.AWAIT_IPV4 || qflg.AWAIT_IPV6) {
                kr_nsrep_elect_addr(qry, request->ctx);
        } else if (qflg.FORWARD || qflg.STUB) {
-               kr_nsrep_sort(&qry->ns, request->ctx->cache_rtt);
-               check_timeouted = true;
+               kr_nsrep_sort(&qry->ns, request->ctx);
+               if (qry->ns.score > KR_NS_MAX_SCORE) {
+                       VERBOSE_MSG(qry, "=> no valid NS left\n");
+                       return KR_STATE_FAIL;
+               }
        } else if (!qry->ns.name || !retry) { /* Keep NS when requerying/stub/badcookie. */
                /* Root DNSKEY must be fetched from the hints to avoid chicken and egg problem. */
                if (qry->sname[0] == '\0' && qry->stype == KNOT_RRTYPE_DNSKEY) {
@@ -1436,22 +1438,20 @@ ns_election:
                        qry->flags.NO_THROTTLE = true; /* Pick even bad SBELT servers */
                }
                kr_nsrep_elect(qry, request->ctx);
-               check_timeouted = true;
-       }
-
-       if (check_timeouted && qry->ns.score > KR_NS_TIMEOUT) {
-               if (kr_zonecut_is_empty(&qry->zone_cut)) {
-                       VERBOSE_MSG(qry, "=> no NS with an address\n");
-               } else {
-                       VERBOSE_MSG(qry, "=> no valid NS left\n");
-               }
-               if (!qry->flags.NO_NS_FOUND) {
-                       qry->flags.NO_NS_FOUND = true;
-               } else {
-                       ITERATE_LAYERS(request, qry, reset);
-                       kr_rplan_pop(rplan, qry);
+               if (qry->ns.score > KR_NS_MAX_SCORE) {
+                       if (kr_zonecut_is_empty(&qry->zone_cut)) {
+                               VERBOSE_MSG(qry, "=> no NS with an address\n");
+                       } else {
+                               VERBOSE_MSG(qry, "=> no valid NS left\n");
+                       }
+                       if (!qry->flags.NO_NS_FOUND) {
+                               qry->flags.NO_NS_FOUND = true;
+                       } else {
+                               ITERATE_LAYERS(request, qry, reset);
+                               kr_rplan_pop(rplan, qry);
+                       }
+                       return KR_STATE_PRODUCE;
                }
-               return KR_STATE_PRODUCE;
        }
 
        /* Resolve address records */