Improve IPv6 NDP for non-local Thread Border routers

buildroot-external/kernel/hassos.config

@@ -60,6 +60,8 @@ CONFIG_BT_HIDP=m
 CONFIG_BT_LEDS=y
 
 CONFIG_IPV6=y
+CONFIG_IPV6_ROUTER_PREF=y
+CONFIG_IPV6_REACHABILITY_PROBE=y
 CONFIG_IPV6_SIT=m
 
 CONFIG_IP_MROUTE=y

buildroot-external/patches/linux/0001-ipv6-add-option-to-explicitly-enable-reachability-te.patch

@@ -0,0 +1,56 @@
+From b9182b02829b158d55acc53a0bcec1ed667b2668 Mon Sep 17 00:00:00 2001
+Message-Id: <b9182b02829b158d55acc53a0bcec1ed667b2668.1680000784.git.stefan@agner.ch>
+From: Stefan Agner <[email protected]>
+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 <[email protected]>
+---
+ 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
+

buildroot-external/patches/network-manager/0001-ndisc-support-multiple-gateways-for-a-single-network.patch

@@ -0,0 +1,27 @@
+From a053500cf43a31ee82a6e0f3d644ea36f5c77ffb Mon Sep 17 00:00:00 2001
+Message-Id: <a053500cf43a31ee82a6e0f3d644ea36f5c77ffb.1679932288.git.stefan@agner.ch>
+From: Stefan Agner <[email protected]>
+Date: Mon, 27 Mar 2023 17:48:34 +0200
+Subject: [PATCH] ndisc: support multiple gateways for a single network
+
+---
+ src/core/ndisc/nm-ndisc.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/src/core/ndisc/nm-ndisc.c b/src/core/ndisc/nm-ndisc.c
+index 9a6038d406..67cdf5d99a 100644
+--- a/src/core/ndisc/nm-ndisc.c
++++ b/src/core/ndisc/nm-ndisc.c
+@@ -654,7 +654,8 @@ nm_ndisc_add_route(NMNDisc *ndisc, const NMNDiscRoute *new_item, gint64 now_msec
+         NMNDiscRoute *item = &g_array_index(rdata->routes, NMNDiscRoute, i);
+
+         if (IN6_ARE_ADDR_EQUAL(&item->network, &new_item->network)
+-            && item->plen == new_item->plen) {
++            && item->plen == new_item->plen
++            && IN6_ARE_ADDR_EQUAL(&item->gateway, &new_item->gateway)) {
+             if (new_item->expiry_msec <= now_msec) {
+                 g_array_remove_index(rdata->routes, i);
+                 return TRUE;
+-- 
+2.40.0
+