Commit 01c41123 authored by Ido Schimmel's avatar Ido Schimmel Committed by Jakub Kicinski
Browse files

seg6: Extend seg6_lookup_any_nexthop() with an oif argument 



seg6_lookup_any_nexthop() is called by the different endpoint behaviors
(e.g., End, End.X) to resolve an IPv6 route. Extend the function with an
output interface argument so that it could be used to resolve a route
with a certain output interface. This will be used by subsequent patches
that will extend the End.X behavior with an output interface as an
optional argument.

ip6_route_input_lookup() cannot be used when an output interface is
specified as it ignores this parameter. Similarly, calling
ip6_pol_route() when a table ID was not specified (e.g., End.X behavior)
is wrong.

Therefore, when an output interface is specified without a table ID,
resolve the route using ip6_route_output() which will take the output
interface into account.

Note that no endpoint behavior currently passes both a table ID and an
output interface, so the oif argument passed to ip6_pol_route() is
always zero and there are no functional changes in this regard.

Signed-off-by: default avatarIdo Schimmel <idosch@nvidia.com>
Reviewed-by: default avatarAndrea Mayer <andrea.mayer@uniroma2.it>
Link: https://patch.msgid.link/20250612122323.584113-2-idosch@nvidia.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 0550890b

net/ipv6/seg6_local.c

+10 −7
Original line number Diff line number Diff line
@@ -270,7 +270,7 @@ static void advance_nextseg(struct ipv6_sr_hdr *srh, struct in6_addr *daddr) 


static int

seg6_lookup_any_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,

			u32 tbl_id, bool local_delivery)

			u32 tbl_id, bool local_delivery, int oif)

{

	struct net *net = dev_net(skb->dev);

	struct ipv6hdr *hdr = ipv6_hdr(skb);
@@ -282,6 +282,7 @@ seg6_lookup_any_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr, 


	memset(&fl6, 0, sizeof(fl6));

	fl6.flowi6_iif = skb->dev->ifindex;

	fl6.flowi6_oif = oif;

	fl6.daddr = nhaddr ? *nhaddr : hdr->daddr;

	fl6.saddr = hdr->saddr;

	fl6.flowlabel = ip6_flowinfo(hdr);
@@ -291,17 +292,19 @@ seg6_lookup_any_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr, 
	if (nhaddr)

		fl6.flowi6_flags = FLOWI_FLAG_KNOWN_NH;



	if (!tbl_id) {

	if (!tbl_id && !oif) {

		dst = ip6_route_input_lookup(net, skb->dev, &fl6, skb, flags);

	} else {

	} else if (tbl_id) {

		struct fib6_table *table;



		table = fib6_get_table(net, tbl_id);

		if (!table)

			goto out;



		rt = ip6_pol_route(net, table, 0, &fl6, skb, flags);

		rt = ip6_pol_route(net, table, oif, &fl6, skb, flags);

		dst = &rt->dst;

	} else {

		dst = ip6_route_output(net, NULL, &fl6);

	}



	/* we want to discard traffic destined for local packet processing,
@@ -330,7 +333,7 @@ seg6_lookup_any_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr, 
int seg6_lookup_nexthop(struct sk_buff *skb,

			struct in6_addr *nhaddr, u32 tbl_id)

{

	return seg6_lookup_any_nexthop(skb, nhaddr, tbl_id, false);

	return seg6_lookup_any_nexthop(skb, nhaddr, tbl_id, false, 0);

}



static __u8 seg6_flv_lcblock_octects(const struct seg6_flavors_info *finfo)
@@ -1277,7 +1280,7 @@ static int input_action_end_dt6(struct sk_buff *skb, 
	/* note: this time we do not need to specify the table because the VRF

	 * takes care of selecting the correct table.

	 */

	seg6_lookup_any_nexthop(skb, NULL, 0, true);

	seg6_lookup_any_nexthop(skb, NULL, 0, true, 0);



	return dst_input(skb);
@@ -1285,7 +1288,7 @@ static int input_action_end_dt6(struct sk_buff *skb, 
#endif

	skb_set_transport_header(skb, sizeof(struct ipv6hdr));



	seg6_lookup_any_nexthop(skb, NULL, slwt->table, true);

	seg6_lookup_any_nexthop(skb, NULL, slwt->table, true, 0);



	return dst_input(skb);