lib/nsrep: force resolution with given NS address

daemon/lua/kres.lua

@@ -242,6 +242,8 @@ struct kr_query *kr_rplan_push(struct kr_rplan *rplan, struct kr_query *parent,
                                const knot_dname_t *name, uint16_t cls, uint16_t type);
 struct kr_query *kr_rplan_resolved(struct kr_rplan *rplan);
 struct kr_query *kr_rplan_next(struct kr_query *qry);
+/* Nameservers */
+int kr_nsrep_set(struct kr_query *qry, uint8_t *addr, size_t addr_len);
 /* Query */
 /* Utils */
 unsigned kr_rand_uint(unsigned max);
@@ -331,6 +333,7 @@ ffi.metatype( knot_pkt_t, {
 	},
 })
 -- Metatype for query
+local ub_t = ffi.typeof('unsigned char *')
 local kr_query_t = ffi.typeof('struct kr_query')
 ffi.metatype( kr_query_t, {
 	__index = {
@@ -345,6 +348,10 @@ ffi.metatype( kr_query_t, {
 		final = function(qry)
 			return qry:resolved() and (qry.parent == nil)
 		end,
+		nslist = function(qry, ns)
+			if ns ~= nil then C.kr_nsrep_set(qry, ffi.cast(ub_t, ns), #ns) end
+			-- @todo: Return list of NS entries, not possible ATM because the NSLIST is union and missing typedef
+		end,
 	},
 })
 -- Metatype for request

lib/nsrep.c

@@ -37,20 +37,18 @@
 } while (0)
 
 /** Update nameserver representation with current name/address pair. */
-static void update_nsrep(struct kr_nsrep *ns, uint8_t *addr, size_t pos)
+static void update_nsrep(struct kr_nsrep *ns, size_t pos, uint8_t *addr, size_t addr_len)
 {
 	if (addr == NULL) {
 		ns->addr[pos].ip.sa_family = AF_UNSPEC;
 		return;
 	}
 
-	size_t len = pack_obj_len(addr);
-	void *addr_val = pack_obj_val(addr);
-	switch(len) {
+	switch(addr_len) {
 	case sizeof(struct in_addr):
-		ADDR_SET(ns->addr[pos].ip4.sin, AF_INET, addr_val, len); break;
+		ADDR_SET(ns->addr[pos].ip4.sin, AF_INET, addr, addr_len); break;
 	case sizeof(struct in6_addr):
-		ADDR_SET(ns->addr[pos].ip6.sin6, AF_INET6, addr_val, len); break;
+		ADDR_SET(ns->addr[pos].ip6.sin6, AF_INET6, addr, addr_len); break;
 	default: assert(0); break;
 	}
 }
@@ -60,7 +58,13 @@ static void update_nsrep_set(struct kr_nsrep *ns, const knot_dname_t *name, uint
 	ns->name = name;
 	ns->score = score;
 	for (size_t i = 0; i < KR_NSREP_MAXADDR; ++i) {
-		update_nsrep(ns, addr[i], i);
+		if (addr[i]) {
+			void *addr_val = pack_obj_val(addr[i]);
+			size_t len = pack_obj_len(addr[i]);
+			update_nsrep(ns, i, addr_val, len);
+		} else {
+			update_nsrep(ns, i, NULL, 0);
+		}
 	}
 }
 
@@ -157,6 +161,19 @@ static int eval_nsrep(const char *k, void *v, void *baton)
 	return kr_ok();
 }
 
+int kr_nsrep_set(struct kr_query *qry, uint8_t *addr, size_t addr_len)
+{
+	if (!qry || !addr) {
+		return kr_error(EINVAL);
+	}
+	qry->ns.name = (const uint8_t *)"";
+	qry->ns.score = KR_NS_UNKNOWN;
+	qry->ns.reputation = 0;
+	update_nsrep(&qry->ns, 0, addr, addr_len);
+	update_nsrep(&qry->ns, 1, NULL, 0);
+	return kr_ok();
+}
+
 #define ELECT_INIT(ns, ctx_) do { \
 	(ns)->ctx = (ctx_); \
 	(ns)->addr[0].ip.sa_family = AF_UNSPEC; \

lib/nsrep.h

@@ -80,6 +80,15 @@ struct kr_nsrep
 #define kr_nsrep_inaddr_len(addr) \
 	((addr).ip.sa_family == AF_INET ? sizeof(struct in_addr) : sizeof(struct in6_addr))
 
+/**
+ * Set given NS address.
+ * @param  qry      updated query
+ * @param  addr     address bytes (struct in_addr or struct in6_addr)
+ * @param  addr_len address bytes length (type will be derived from this)
+ * @return          0 or an error code
+ */
+int kr_nsrep_set(struct kr_query *qry, uint8_t *addr, size_t addr_len);
+
 /**
  * Elect best nameserver/address pair from the nsset.
  * @param  qry          updated query

lib/utils.c

@@ -217,7 +217,11 @@ int kr_straddr_family(const char *addr)
 
 int kr_family_len(int family)
 {
-	return (family == AF_INET) ? sizeof(struct in_addr) : sizeof(struct in6_addr);
+	switch (family) {
+	case AF_INET:  return sizeof(struct in_addr);
+	case AF_INET6: return sizeof(struct in6_addr);
+	default:       return kr_error(EINVAL);
+	}
 }
 
 int kr_straddr_subnet(void *dst, const char *addr)