From 640556c692962388bd0cb5b8285f602af63839ee Mon Sep 17 00:00:00 2001
From: Willy Tarreau <w@1wt.eu>
Date: Fri, 9 May 2014 23:38:15 +0200
Subject: [PATCH] BUG/MINOR: checks: correctly configure the address family and
 protocol

Currently, mixing an IPv4 and an IPv6 address in checks happens to
work by pure luck because the two protocols use the same functions
at the socket level and both use IPPROTO_TCP. However, they're
definitely wrong as the protocol for the check address is retrieved
from the server's address.

Now the protocol assigned to the connection is the same as the one
the address in use belongs to (eg: the server's address or the
explicit check address).
---
 src/checks.c | 24 +++++++++++++++---------
 src/server.c |  1 +
 2 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/src/checks.c b/src/checks.c
index fceb2c74e..5eb5a76c8 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -1509,6 +1509,7 @@ static struct task *process_chk(struct task *t)
 	struct check *check = t->context;
 	struct server *s = check->server;
 	struct connection *conn = check->conn;
+	struct protocol *proto;
 	int rv;
 	int ret;
 	int expired = tick_is_expired(t->expire, now_ms);
@@ -1573,12 +1574,16 @@ static struct task *process_chk(struct task *t)
 		/* no client address */
 		clear_addr(&conn->addr.from);
 
-		if (is_addr(&s->check_common.addr))
+		if (is_addr(&s->check_common.addr)) {
 			/* we'll connect to the check addr specified on the server */
 			conn->addr.to = s->check_common.addr;
-		else
+			proto = s->check_common.proto;
+		}
+		else {
 			/* we'll connect to the addr on the server */
 			conn->addr.to = s->addr;
+			proto = s->proto;
+		}
 
 		if (check->port) {
 			set_host_port(&conn->addr.to, check->port);
@@ -1606,8 +1611,8 @@ static struct task *process_chk(struct task *t)
 		 * connect() when a pure TCP check is used (without PROXY protocol).
 		 */
 		ret = SN_ERR_INTERNAL;
-		if (s->check_common.proto->connect)
-			ret = s->check_common.proto->connect(conn, check->type, (check->type) ? 0 : 2);
+		if (proto->connect)
+			ret = proto->connect(conn, check->type, (check->type) ? 0 : 2);
 		conn->flags |= CO_FL_WAKE_DATA;
 		if (s->check.send_proxy) {
 			conn->send_proxy_ofs = 1;
@@ -2075,15 +2080,16 @@ static void tcpcheck_main(struct connection *conn)
 			/* no client address */
 			clear_addr(&conn->addr.from);
 
-			if (is_addr(&s->check_common.addr))
+			if (is_addr(&s->check_common.addr)) {
 				/* we'll connect to the check addr specified on the server */
 				conn->addr.to = s->check_common.addr;
-			else
+				proto = s->check_common.proto;
+			}
+			else {
 				/* we'll connect to the addr on the server */
 				conn->addr.to = s->addr;
-
-			/* protocol */
-			proto = protocol_by_family(conn->addr.to.ss_family);
+				proto = s->proto;
+			}
 
 			/* port */
 			if (check->current_step->port)
diff --git a/src/server.c b/src/server.c
index 565a108be..51bb85aff 100644
--- a/src/server.c
+++ b/src/server.c
@@ -597,6 +597,7 @@ int parse_server(const char *file, int linenum, char **args, struct proxy *curpr
 				}
 
 				newsrv->check_common.addr = *sk;
+				newsrv->check_common.proto = protocol_by_family(sk->ss_family);
 				cur_arg += 2;
 			}
 			else if (!strcmp(args[cur_arg], "port")) {