Merge branch '4736-isc_r_hostdown-was-not-being-handled-by-resolver-c…

…' into 'main'

Resolve "ISC_R_HOSTDOWN was not being handled by resolver.c"

Closes #4736

See merge request isc-projects/bind9!9055

CHANGES

@@ -1,3 +1,6 @@
+6395.	[bug]		Handle ISC_R_HOSTDOWN and ISC_R_NETDOWN in resolver.c.
+			[GL #4736]
+
 6394.	[bug]		Named's -4 and -6 options now apply to zone primaries,
 			also-notify and parental-agents.  Report when a zone
 			has these options configured but does not have an IPv4

lib/dns/resolver.c

@@ -1752,11 +1752,15 @@ resquery_senddone(isc_result_t eresult, isc_region_t *region, void *arg) {
 	case ISC_R_SHUTTINGDOWN:
 		break;
 
+	case ISC_R_HOSTDOWN:
 	case ISC_R_HOSTUNREACH:
+	case ISC_R_NETDOWN:
 	case ISC_R_NETUNREACH:
 	case ISC_R_NOPERM:
 	case ISC_R_ADDRNOTAVAIL:
 	case ISC_R_CONNREFUSED:
+	case ISC_R_CONNECTIONRESET:
+	case ISC_R_TIMEDOUT:
 		/* No route to remote. */
 		FCTXTRACE3("query canceled in resquery_senddone(): "
 			   "no route to host; no response",
@@ -2829,8 +2833,10 @@ resquery_connected(isc_result_t eresult, isc_region_t *region, void *arg) {
 		fctx_done_detach(&fctx, eresult);
 		break;
 
-	case ISC_R_NETUNREACH:
+	case ISC_R_HOSTDOWN:
 	case ISC_R_HOSTUNREACH:
+	case ISC_R_NETDOWN:
+	case ISC_R_NETUNREACH:
 	case ISC_R_CONNREFUSED:
 	case ISC_R_NOPERM:
 	case ISC_R_ADDRNOTAVAIL:
@@ -7756,7 +7762,9 @@ rctx_dispfail(respctx_t *rctx) {
 	 */
 	switch (rctx->result) {
 	case ISC_R_EOF:
+	case ISC_R_HOSTDOWN:
 	case ISC_R_HOSTUNREACH:
+	case ISC_R_NETDOWN:
 	case ISC_R_NETUNREACH:
 	case ISC_R_CONNREFUSED:
 	case ISC_R_CONNECTIONRESET: