From c8f919ecd33d1185a072647e05637481a3e9501d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Vavru=C5=A1a?= <marek.vavrusa@nic.cz>
Date: Mon, 8 Dec 2014 14:02:05 +0100
Subject: [PATCH] resolve: set limit to prevent infinite loops on server
failure
---
daemon/layer/query.c | 2 +-
lib/resolve.c | 15 ++++++++++++++-
2 files changed, 15 insertions(+), 2 deletions(-)
diff --git a/daemon/layer/query.c b/daemon/layer/query.c
index f97bb4471..662e79d8e 100644
--- a/daemon/layer/query.c
+++ b/daemon/layer/query.c
@@ -52,7 +52,7 @@ static int input_query(knot_layer_t *ctx, knot_pkt_t *pkt)
knot_pkt_t *answer = param->result->ans;
knot_wire_set_id(answer->wire, knot_wire_get_id(pkt->wire));
- if (ret != 0) {
+ if (ret != KNOT_EOK) {
return KNOT_NS_PROC_FAIL;
} else {
return KNOT_NS_PROC_DONE;
diff --git a/lib/resolve.c b/lib/resolve.c
index 779f0fd79..8dd8ec043 100644
--- a/lib/resolve.c
+++ b/lib/resolve.c
@@ -12,6 +12,8 @@
#define DEBUG_MSG(fmt, ...) fprintf(stderr, "[reslv] " fmt, ## __VA_ARGS__)
static int resolve_ns(struct kr_context *resolve, struct kr_ns *ns)
+/* Defines */
+#define ITER_LIMIT 50
{
/* Create an address query. */
struct kr_query *qry = kr_rplan_push(&resolve->rplan, ns->name,
@@ -114,12 +116,23 @@ int kr_resolve(struct kr_context* ctx, struct kr_result* result,
knot_requestor_overlay(&requestor, LAYER_STATIC, ¶m);
knot_requestor_overlay(&requestor, LAYER_ITERATE, ¶m);
knot_requestor_overlay(&requestor, LAYER_STATS, ¶m);
+ unsigned iter_count = 0;
while(ctx->state & (KNOT_NS_PROC_MORE|KNOT_NS_PROC_FULL)) {
iterate(&requestor, ctx);
+ if (++iter_count > ITER_LIMIT) {
+ DEBUG_MSG("iteration limit %d reached => SERVFAIL\n", ITER_LIMIT);
+ ctx->state = KNOT_NS_PROC_FAIL;
+ }
}
/* Clean up. */
knot_requestor_clear(&requestor);
- return 0;
+ /* Set RCODE on internal failure. */
+ if (ctx->state != KNOT_NS_PROC_DONE) {
+ knot_wire_set_rcode(result->ans->wire, KNOT_RCODE_SERVFAIL);
+ return KNOT_ERROR;
+ }
+
+ return KNOT_EOK;
}
--
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