IPVS: Add function to determine if IPv6 address is local

Add __ip_vs_addr_is_local_v6() to find out if an IPv6 address belongs to a
local interface. Use this function to decide whether to set the
IP_VS_CONN_F_LOCALNODE flag for IPv6 destinations.

Signed-off-by: Vince Busam <vbusam@google.com>
Signed-off-by: Simon Horman <horms@verge.net.au>

1 files changed, 49 insertions, 7 deletions

diff --git a/net/ipv4/ipvs/ip_vs_ctl.c b/net/ipv4/ipvs/ip_vs_ctl.c
index 25d9e98e31f..640203a153c 100644
--- a/net/ipv4/ipvs/ip_vs_ctl.c
+++ b/net/ipv4/ipvs/ip_vs_ctl.c
@@ -35,6 +35,10 @@
 
 #include <net/net_namespace.h>
 #include <net/ip.h>
+#ifdef CONFIG_IP_VS_IPV6
+#include <net/ipv6.h>
+#include <net/ip6_route.h>
+#endif
 #include <net/route.h>
 #include <net/sock.h>
 #include <net/genetlink.h>
@@ -91,6 +95,26 @@ int ip_vs_get_debug_level(void)
 }
 #endif
 
+#ifdef CONFIG_IP_VS_IPV6
+/* Taken from rt6_fill_node() in net/ipv6/route.c, is there a better way? */
+static int __ip_vs_addr_is_local_v6(const struct in6_addr *addr)
+{
+        struct rt6_info *rt;
+        struct flowi fl = {
+                .oif = 0,
+                .nl_u = {
+                        .ip6_u = {
+                                .daddr = *addr,
+                                .saddr = { .s6_addr32 = {0, 0, 0, 0} }, } },
+        };
+
+        rt = (struct rt6_info *)ip6_route_output(&init_net, NULL, &fl);
+        if (rt && rt->rt6i_dev && (rt->rt6i_dev->flags & IFF_LOOPBACK))
+                        return 1;
+
+        return 0;
+}
+#endif
 /*
  *      update_defense_level is called from keventd and from sysctl,
  *      so it needs to protect itself from softirqs
@@ -751,10 +775,18 @@ __ip_vs_update_dest(struct ip_vs_service *svc,
         conn_flags = udest->conn_flags | IP_VS_CONN_F_INACTIVE;
 
         /* check if local node and update the flags */
-        if (inet_addr_type(&init_net, udest->addr.ip) == RTN_LOCAL) {
-                conn_flags = (conn_flags & ~IP_VS_CONN_F_FWD_MASK)
-                        | IP_VS_CONN_F_LOCALNODE;
-        }
+#ifdef CONFIG_IP_VS_IPV6
+        if (svc->af == AF_INET6) {
+                if (__ip_vs_addr_is_local_v6(&udest->addr.in6)) {
+                        conn_flags = (conn_flags & ~IP_VS_CONN_F_FWD_MASK)
+                                | IP_VS_CONN_F_LOCALNODE;
+                }
+        } else
+#endif
+                if (inet_addr_type(&init_net, udest->addr.ip) == RTN_LOCAL) {
+                        conn_flags = (conn_flags & ~IP_VS_CONN_F_FWD_MASK)
+                                | IP_VS_CONN_F_LOCALNODE;
+                }
 
         /* set the IP_VS_CONN_F_NOOUTPUT flag if not masquerading/NAT */
         if ((conn_flags & IP_VS_CONN_F_FWD_MASK) != 0) {
@@ -803,9 +835,19 @@ ip_vs_new_dest(struct ip_vs_service *svc, struct ip_vs_dest_user_kern *udest,
 
         EnterFunction(2);
 
-        atype = inet_addr_type(&init_net, udest->addr.ip);
-        if (atype != RTN_LOCAL && atype != RTN_UNICAST)
-                return -EINVAL;
+#ifdef CONFIG_IP_VS_IPV6
+        if (svc->af == AF_INET6) {
+                atype = ipv6_addr_type(&udest->addr.in6);
+                if (!(atype & IPV6_ADDR_UNICAST) &&
+                        !__ip_vs_addr_is_local_v6(&udest->addr.in6))
+                        return -EINVAL;
+        } else
+#endif
+        {
+                atype = inet_addr_type(&init_net, udest->addr.ip);
+                if (atype != RTN_LOCAL && atype != RTN_UNICAST)
+                        return -EINVAL;
+        }
 
         dest = kzalloc(sizeof(struct ip_vs_dest), GFP_ATOMIC);
         if (dest == NULL) {