xfrm: interface: support IP6IP6 and IP6IP tunnels processing with .cb_handler

Similar to ip6_vti, IP6IP6 and IP6IP tunnels processing can easily
be done with .cb_handler for xfrm interface.

v1->v2:
  - no change.
v2-v3:
  - enable it only when CONFIG_INET6_XFRM_TUNNEL is defined, to fix
    the build error, reported by kbuild test robot.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c
index c407ecbc5d462b952aa60cf41c98e8a5c7e39ddf..b9ef496d3d7cd650f80eaa4e11fd0386b502dbc1 100644 (file)
--- a/net/xfrm/xfrm_interface.c
+++ b/net/xfrm/xfrm_interface.c
@@ -798,6 +798,26 @@ static struct xfrm6_protocol xfrmi_ipcomp6_protocol __read_mostly = {
        .priority       =       10,
 };
 
+#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
+static int xfrmi6_rcv_tunnel(struct sk_buff *skb)
+{
+       const xfrm_address_t *saddr;
+       __be32 spi;
+
+       saddr = (const xfrm_address_t *)&ipv6_hdr(skb)->saddr;
+       spi = xfrm6_tunnel_spi_lookup(dev_net(skb->dev), saddr);
+
+       return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi, NULL);
+}
+
+static struct xfrm6_tunnel xfrmi_ipv6_handler __read_mostly = {
+       .handler        =       xfrmi6_rcv_tunnel,
+       .cb_handler     =       xfrmi_rcv_cb,
+       .err_handler    =       xfrmi6_err,
+       .priority       =       -1,
+};
+#endif
+
 static struct xfrm4_protocol xfrmi_esp4_protocol __read_mostly = {
        .handler        =       xfrm4_rcv,
        .input_handler  =       xfrm_input,
@@ -866,9 +886,23 @@ static int __init xfrmi6_init(void)
        err = xfrm6_protocol_register(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
        if (err < 0)
                goto xfrm_proto_comp_failed;
+#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
+       err = xfrm6_tunnel_register(&xfrmi_ipv6_handler, AF_INET6);
+       if (err < 0)
+               goto xfrm_tunnel_ipv6_failed;
+       err = xfrm6_tunnel_register(&xfrmi_ipv6_handler, AF_INET);
+       if (err < 0)
+               goto xfrm_tunnel_ip6ip_failed;
+#endif
 
        return 0;
 
+#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
+xfrm_tunnel_ip6ip_failed:
+       xfrm6_tunnel_deregister(&xfrmi_ipv6_handler, AF_INET6);
+xfrm_tunnel_ipv6_failed:
+       xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
+#endif
 xfrm_proto_comp_failed:
        xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
 xfrm_proto_ah_failed:
@@ -879,6 +913,10 @@ xfrm_proto_esp_failed:
 
 static void xfrmi6_fini(void)
 {
+#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
+       xfrm6_tunnel_deregister(&xfrmi_ipv6_handler, AF_INET);
+       xfrm6_tunnel_deregister(&xfrmi_ipv6_handler, AF_INET6);
+#endif
        xfrm6_protocol_deregister(&xfrmi_ipcomp6_protocol, IPPROTO_COMP);
        xfrm6_protocol_deregister(&xfrmi_ah6_protocol, IPPROTO_AH);
        xfrm6_protocol_deregister(&xfrmi_esp6_protocol, IPPROTO_ESP);