lib: bail out on irresolvable nameservers

lib/layer/iterate.c

@@ -309,7 +309,7 @@ static int process_answer(knot_pkt_t *pkt, struct kr_layer_param *param)
 	}
 
 	/* Either way it resolves current query. */
-	query->resolved = true;
+	query->flags |= QUERY_RESOLVED;
 	return KNOT_STATE_DONE;
 }
 
@@ -389,7 +389,7 @@ static int resolve(knot_layer_t *ctx, knot_pkt_t *pkt)
 	assert(pkt && ctx);
 	struct kr_layer_param *param = ctx->data;
 	struct kr_query *query = kr_rplan_current(param->rplan);
-	if (query == NULL || query->resolved) {
+	if (query == NULL || (query->flags & QUERY_RESOLVED)) {
 		return ctx->state;
 	}
 

lib/layer/itercache.c

@@ -21,6 +21,7 @@
 #include <libknot/rrtype/rdname.h>
 
 #include "lib/layer/iterate.h"
+#include "lib/cache.h"
 #include "lib/module.h"
 
 #define DEBUG_MSG(fmt...) QRDEBUG(kr_rplan_current(param->rplan), " cc ",  fmt)
@@ -95,7 +96,7 @@ static int read_cache(knot_layer_t *ctx, knot_pkt_t *pkt)
 	int state = read_cache_rr(txn, &cache_rr, timestamp, callback, param);
 	if (state == KNOT_STATE_DONE) {
 		DEBUG_MSG("=> satisfied from cache\n");
-		cur->resolved = true;
+		cur->flags |= QUERY_RESOLVED;
 		return state;
 	}
 
@@ -110,7 +111,7 @@ static int read_cache(knot_layer_t *ctx, knot_pkt_t *pkt)
 			}
 		}
 
-		cur->resolved = true;
+		cur->flags |= QUERY_RESOLVED;
 		return KNOT_STATE_DONE;
 	}
 

lib/resolve.c

@@ -46,6 +46,7 @@ static int ns_resolve_addr(struct kr_query *cur, struct kr_layer_param *param)
 {
 	if (kr_rplan_satisfies(cur, cur->ns.name, KNOT_CLASS_IN, KNOT_RRTYPE_A) ||
 	    kr_rplan_satisfies(cur, cur->ns.name, KNOT_CLASS_IN, KNOT_RRTYPE_AAAA) ||
+	    cur->flags & QUERY_AWAIT_ADDR) {
 		DEBUG_MSG("=> dependency loop, bailing out\n");
 		kr_rplan_pop(param->rplan, cur);
 		return KNOT_EOK;
@@ -53,6 +54,7 @@ static int ns_resolve_addr(struct kr_query *cur, struct kr_layer_param *param)
 
 	(void) kr_rplan_push(param->rplan, cur, cur->ns.name, KNOT_CLASS_IN, KNOT_RRTYPE_AAAA);
 	(void) kr_rplan_push(param->rplan, cur, cur->ns.name, KNOT_CLASS_IN, KNOT_RRTYPE_A);
+	cur->flags |= QUERY_AWAIT_ADDR;
 	return KNOT_EOK;
 }
 

lib/rplan.h

@@ -34,7 +34,9 @@
 /** Query flags */
 enum kr_query_flag {
 	QUERY_NO_MINIMIZE = 1 << 0, /**< Don't minimize QNAME. */
-	QUERY_TCP         = 1 << 1  /**< Use TCP for this query. */
+	QUERY_TCP         = 1 << 1, /**< Use TCP for this query. */
+	QUERY_RESOLVED    = 1 << 2, /**< Query is resolved. */
+	QUERY_AWAIT_ADDR  = 1 << 3  /**< Query is waiting for NS address. */
 };
 
 /**
@@ -47,7 +49,6 @@ struct kr_query {
 	struct kr_zonecut zone_cut;
 	struct timeval timestamp;
 	knot_dname_t *sname;
-	bool resolved;
 	uint16_t stype;
 	uint16_t sclass;
 	uint16_t id;

modules/hints/hints.c

@@ -93,7 +93,7 @@ static int query(knot_layer_t *ctx, knot_pkt_t *pkt)
 			knot_rrset_add_rdata(&rr, raw_addr, addr_len, 0, &param->answer->mm);
 			callback(&rr, 0, param);
 
-			cur->resolved = true;
+			cur->flags |= QUERY_RESOLVED;
 			return KNOT_STATE_DONE;
 		}
 	}