seg6: add support for IPv4 decapsulation in ipv6_srh_rcv()

As specified in IETF RFC 8754, section 4.3.1.2, if the upper layer
header is IPv4 or IPv6, perform IPv6 decapsulation and resubmit the
decapsulated packet to the IPv4 or IPv6 module.
Only IPv6 decapsulation was implemented. This patch adds support for IPv4
decapsulation.

Link: https://tools.ietf.org/html/rfc8754#section-4.3.1.2
Signed-off-by: Julien Massonneau <julien.massonneau@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Julien Massonneau 2021-03-11 16:53:18 +01:00 committed by David S. Miller
parent 6c6095214a
commit ee90c6ba34
2 changed files with 4 additions and 2 deletions

View file

@ -30,6 +30,7 @@
*/
#define NEXTHDR_HOP 0 /* Hop-by-hop option header. */
#define NEXTHDR_IPV4 4 /* IPv4 in IPv6 */
#define NEXTHDR_TCP 6 /* TCP segment. */
#define NEXTHDR_UDP 17 /* UDP message. */
#define NEXTHDR_IPV6 41 /* IPv6 in IPv6 */

View file

@ -381,7 +381,7 @@ static int ipv6_srh_rcv(struct sk_buff *skb)
looped_back:
if (hdr->segments_left == 0) {
if (hdr->nexthdr == NEXTHDR_IPV6) {
if (hdr->nexthdr == NEXTHDR_IPV6 || hdr->nexthdr == NEXTHDR_IPV4) {
int offset = (hdr->hdrlen + 1) << 3;
skb_postpull_rcsum(skb, skb_network_header(skb),
@ -397,7 +397,8 @@ static int ipv6_srh_rcv(struct sk_buff *skb)
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
skb->encapsulation = 0;
if (hdr->nexthdr == NEXTHDR_IPV4)
skb->protocol = htons(ETH_P_IP);
__skb_tunnel_rx(skb, skb->dev, net);
netif_rx(skb);