From: Yorgos Thessalonikefs <yorgos@nlnetlabs.nl>
Date: Mon, 17 Feb 2025 14:21:18 +0000 (+0100)
Subject: - Consider reconfigurations when calculating the still_useful_timeout
X-Git-Tag: release-1.23.0rc1~50
X-Git-Url: http://git.ipfire.org/gitweb/gitweb.cgi?a=commitdiff_plain;h=72828ff81c4fad197a5b4ec7db3b4f649bccbbb9;p=thirdparty%2Funbound.git

- Consider reconfigurations when calculating the still_useful_timeout
  for servers in the infrastructure cache.
---

diff --git a/doc/Changelog b/doc/Changelog
index b33dfa8e8..e4d8aada0 100644
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -1,3 +1,7 @@
+17 February 2025: Yorgos
+	- Consider reconfigurations when calculating the still_useful_timeout
+	  for servers in the infrastructure cache.
+
 30 January 2025: Wouter
 	- Fix #986: Resolving sas.com with dnssec-validation fails though
 	  signed delegations seem to be (mostly) correct.
diff --git a/services/cache/infra.c b/services/cache/infra.c
index bb3ee87e9..0ed3c297b 100644
--- a/services/cache/infra.c
+++ b/services/cache/infra.c
@@ -60,16 +60,6 @@
  * can do this number of packets (until those all timeout too) */
 #define TIMEOUT_COUNT_MAX 3
 
-/** Minus 1000 because that is outside of the RTTBAND, so
- * blacklisted servers stay blacklisted if this is chosen.
- * If USEFUL_SERVER_TOP_TIMEOUT is below 1000 (configured via RTT_MAX_TIMEOUT,
- * infra-cache-max-rtt) change it to just above the RTT_BAND. */
-#define STILL_USEFUL_TIMEOUT (				\
-	USEFUL_SERVER_TOP_TIMEOUT < 1000 ||		\
-	USEFUL_SERVER_TOP_TIMEOUT - 1000 <= RTT_BAND	\
-		?RTT_BAND + 1				\
-		:USEFUL_SERVER_TOP_TIMEOUT - 1000)
-
 /** ratelimit value for delegation point */
 int infra_dp_ratelimit = 0;
 
@@ -82,6 +72,19 @@ int infra_ip_ratelimit = 0;
  *  For clients with a valid DNS Cookie. */
 int infra_ip_ratelimit_cookie = 0;
 
+/** Minus 1000 because that is outside of the RTTBAND, so
+ * blacklisted servers stay blacklisted if this is chosen.
+ * If USEFUL_SERVER_TOP_TIMEOUT is below 1000 (configured via RTT_MAX_TIMEOUT,
+ * infra-cache-max-rtt) change it to just above the RTT_BAND. */
+static int still_useful_timeout()
+{
+	return
+	USEFUL_SERVER_TOP_TIMEOUT < 1000 ||
+	USEFUL_SERVER_TOP_TIMEOUT - 1000 <= RTT_BAND
+		?RTT_BAND + 1
+		:USEFUL_SERVER_TOP_TIMEOUT - 1000;
+}
+
 size_t 
 infra_sizefunc(void* k, void* ATTR_UNUSED(d))
 {
@@ -668,7 +671,7 @@ infra_update_tcp_works(struct infra_cache* infra,
 	if(data->rtt.rto >= RTT_MAX_TIMEOUT)
 		/* do not disqualify this server altogether, it is better
 		 * than nothing */
-		data->rtt.rto = STILL_USEFUL_TIMEOUT;
+		data->rtt.rto = still_useful_timeout();
 	lock_rw_unlock(&e->lock);
 }
 
@@ -808,7 +811,7 @@ infra_get_lame_rtt(struct infra_cache* infra,
 		&& infra->infra_keep_probing) {
 		/* single probe, keep probing */
 		if(*rtt >= USEFUL_SERVER_TOP_TIMEOUT)
-			*rtt = STILL_USEFUL_TIMEOUT;
+			*rtt = still_useful_timeout();
 	} else if(host->rtt.rto >= PROBE_MAXRTO && timenow < host->probedelay
 		&& rtt_notimeout(&host->rtt)*4 <= host->rtt.rto) {
 		/* single probe for this domain, and we are not probing */
@@ -816,15 +819,15 @@ infra_get_lame_rtt(struct infra_cache* infra,
 		if(qtype == LDNS_RR_TYPE_A) {
 			if(host->timeout_A >= TIMEOUT_COUNT_MAX)
 				*rtt = USEFUL_SERVER_TOP_TIMEOUT;
-			else	*rtt = STILL_USEFUL_TIMEOUT;
+			else	*rtt = still_useful_timeout();
 		} else if(qtype == LDNS_RR_TYPE_AAAA) {
 			if(host->timeout_AAAA >= TIMEOUT_COUNT_MAX)
 				*rtt = USEFUL_SERVER_TOP_TIMEOUT;
-			else	*rtt = STILL_USEFUL_TIMEOUT;
+			else	*rtt = still_useful_timeout();
 		} else {
 			if(host->timeout_other >= TIMEOUT_COUNT_MAX)
 				*rtt = USEFUL_SERVER_TOP_TIMEOUT;
-			else	*rtt = STILL_USEFUL_TIMEOUT;
+			else	*rtt = still_useful_timeout();
 		}
 	}
 	/* expired entry */
@@ -832,7 +835,7 @@ infra_get_lame_rtt(struct infra_cache* infra,
 		/* see if this can be a re-probe of an unresponsive server */
 		if(host->rtt.rto >= USEFUL_SERVER_TOP_TIMEOUT) {
 			lock_rw_unlock(&e->lock);
-			*rtt = STILL_USEFUL_TIMEOUT;
+			*rtt = still_useful_timeout();
 			*lame = 0;
 			*dnsseclame = 0;
 			*reclame = 0;