From b9182b02829b158d55acc53a0bcec1ed667b2668 Mon Sep 17 00:00:00 2001 Message-Id: From: Stefan Agner Date: Tue, 28 Mar 2023 12:02:10 +0200 Subject: [PATCH] ipv6: add option to explicitly enable reachability test Systems which act as host as well as router might prefer the host behavior. Currently the kernel does not allow to use IPv6 forwarding globally and at the same time use route reachability probing. Add a compile time flag to enable route reachability probe in any case. Signed-off-by: Stefan Agner --- net/ipv6/Kconfig | 9 +++++++++ net/ipv6/route.c | 3 ++- 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig index 658bfed1df8b..5147fd4c93ff 100644 --- a/net/ipv6/Kconfig +++ b/net/ipv6/Kconfig @@ -48,6 +48,15 @@ config IPV6_OPTIMISTIC_DAD If unsure, say N. +config IPV6_REACHABILITY_PROBE + bool "IPv6: Always use reachability probing (RFC 4191)" + help + By default reachability probing is disabled on router devices (when + IPv6 forwarding is enabled). This option explicitly enables + reachability probing always. + + If unsure, say N. + config INET6_AH tristate "IPv6: AH transformation" select XFRM_AH diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 0fdb03df2287..5e1e1f02f400 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2210,7 +2210,8 @@ struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, strict |= flags & RT6_LOOKUP_F_IFACE; strict |= flags & RT6_LOOKUP_F_IGNORE_LINKSTATE; - if (net->ipv6.devconf_all->forwarding == 0) + if (net->ipv6.devconf_all->forwarding == 0 || + IS_ENABLED(IPV6_REACHABILITY_PROBE)) strict |= RT6_LOOKUP_F_REACHABLE; rcu_read_lock(); -- 2.40.0