From 987e16d6f4b0cc4614cf87f4b849531d32312a2b Mon Sep 17 00:00:00 2001
From: Baptiste Assmann <bedis9@gmail.com>
Date: Wed, 2 Nov 2016 22:23:31 +0100
Subject: [PATCH] MINOR: dns: implement extra 'hold' timers.

This adds new "hold" timers : nx, refused, timeout, other. This timers
will be used to tell HAProxy to keep an erroneous response as valid for
the corresponding period. For now they're only configured, not enforced.
---
 doc/configuration.txt |  9 +++++++--
 include/types/dns.h   |  4 ++++
 src/cfgparse.c        | 19 ++++++++++++++++---
 3 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/doc/configuration.txt b/doc/configuration.txt
index b5127d6382..147a9fbe7f 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -11347,12 +11347,13 @@ nameserver <id> <ip>:<port>
 hold <status> <period>
   Defines <period> during which the last name resolution should be kept based
   on last resolution <status>
-    <status> : last name resolution status. Only "valid" is accepted for now.
+    <status> : last name resolution status. Acceptable values are "nx",
+               "other", "refused", "timeout", "valid".
     <period> : interval between two successive name resolution when the last
                answer was in <status>. It follows the HAProxy time format.
                <period> is in milliseconds by default.
 
-  Default value is 10s for "valid".
+  Default value is 10s for "valid" and 30s for others.
 
   Note: since the name resolution is triggered by the health checks, a new
         resolution is triggered after <period> modulo the <inter> parameter of
@@ -11384,6 +11385,10 @@ timeout <event> <time>
      nameserver dns2 10.0.0.2:53
      resolve_retries       3
      timeout retry         1s
+     hold other           30s
+     hold refused         30s
+     hold nx              30s
+     hold timeout         30s
      hold valid           10s
 
 
diff --git a/include/types/dns.h b/include/types/dns.h
index b339249077..acff53a2ed 100644
--- a/include/types/dns.h
+++ b/include/types/dns.h
@@ -148,6 +148,10 @@ struct dns_resolvers {
 	} timeout;
 	struct {			/* time to hold current data when */
 		int valid;		/*   a response is valid */
+		int nx;                 /*   a response doesn't exist */
+		int timeout;            /*   no answer was delivered */
+		int refused;            /*   dns server refused to answer */
+		int other;              /*   other dns response errors */
 	} hold;
 	struct task *t;			/* timeout management */
 	struct list curr_resolution;	/* current running resolutions */
diff --git a/src/cfgparse.c b/src/cfgparse.c
index 4923d86094..356ae98107 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -2363,6 +2363,11 @@ int cfg_parse_resolvers(const char *file, int linenum, char **args, int kwm)
 		curr_resolvers->conf.line = linenum;
 		curr_resolvers->id = strdup(args[1]);
 		curr_resolvers->query_ids = EB_ROOT;
+		/* default hold period for nx, other, refuse and timeout is 30s */
+		curr_resolvers->hold.nx = 30000;
+		curr_resolvers->hold.other = 30000;
+		curr_resolvers->hold.refused = 30000;
+		curr_resolvers->hold.timeout = 30000;
 		/* default hold period for valid is 10s */
 		curr_resolvers->hold.valid = 10000;
 		curr_resolvers->timeout.retry = 1000;
@@ -2462,11 +2467,19 @@ int cfg_parse_resolvers(const char *file, int linenum, char **args, int kwm)
 			err_code |= ERR_ALERT | ERR_FATAL;
 			goto out;
 		}
-		if (strcmp(args[1], "valid") == 0)
+		if (strcmp(args[1], "nx") == 0)
+			curr_resolvers->hold.nx = time;
+		else if (strcmp(args[1], "other") == 0)
+			curr_resolvers->hold.other = time;
+		else if (strcmp(args[1], "refused") == 0)
+			curr_resolvers->hold.refused = time;
+		else if (strcmp(args[1], "timeout") == 0)
+			curr_resolvers->hold.timeout = time;
+		else if (strcmp(args[1], "valid") == 0)
 			curr_resolvers->hold.valid = time;
 		else {
-			Alert("parsing [%s:%d] : '%s' unknown <event>: '%s', expects 'valid'\n",
-			file, linenum, args[0], args[1]);
+			Alert("parsing [%s:%d] : '%s' unknown <event>: '%s', expects either 'nx', 'timeout', 'valid', or 'other'.\n",
+				file, linenum, args[0], args[1]);
 			err_code |= ERR_ALERT | ERR_FATAL;
 			goto out;
 		}
-- 
2.47.3