From: Wouter Wijngaards <wouter@nlnetlabs.nl>
Date: Fri, 6 Jul 2018 14:14:19 +0000 (+0000)
Subject: Fix round robin for failed addresses with prefer-ip6: yes
X-Git-Tag: release-1.8.0rc1~107
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=86f16bef93b33de4c916458f3c7a4f14eb0f5925;p=thirdparty%2Funbound.git

Fix round robin for failed addresses with prefer-ip6: yes


git-svn-id: file:///svn/unbound/trunk@4775 be551aaa-1e26-0410-a405-d3ace91eadb9
---

diff --git a/iterator/iter_utils.c b/iterator/iter_utils.c
index 0a8f7700f..df66776ae 100644
--- a/iterator/iter_utils.c
+++ b/iterator/iter_utils.c
@@ -375,12 +375,20 @@ iter_filter_order(struct iter_env* iter_env, struct module_env* env,
 		int got_num6 = 0;
 		int low_rtt6 = 0;
 		int i;
+		int attempt = -1; /* filter to make sure addresses have
+		  less attempts on them than the first, to force round
+		  robin when all the IPv6 addresses fail */
 		prev = NULL;
 		a = dp->result_list;
 		for(i = 0; i < got_num; i++) {
 			swap_to_front = 0;
-			if(a->addr.ss_family == AF_INET6) {
+			if(a->addr.ss_family != AF_INET6 && attempt == -1)
+				attempt = a->attempts;
+			if(a->addr.ss_family == AF_INET6 &&
+				(attempt==-1 || a->attempts<=attempt)) {
 				got_num6++;
+				if(attempt == -1)
+					attempt = a->attempts;
 				swap_to_front = 1;
 				if(low_rtt6 == 0 || a->sel_rtt < low_rtt6) {
 					low_rtt6 = a->sel_rtt;