ip6_tunnel: add generic MPLS receive support

Add support for MPLS in receive side.

Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 6b94c87..821d96c 100644 (file)
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -89,6 +89,11 @@ struct ip6_tnl_net {
        struct ip6_tnl __rcu *collect_md_tun;
 };
 
+static inline int ip6_tnl_mpls_supported(void)
+{
+       return IS_ENABLED(CONFIG_MPLS);
+}
+
 static struct net_device_stats *ip6_get_stats(struct net_device *dev)
 {
        struct pcpu_sw_netstats tmp, sum = { 0 };
@@ -718,6 +723,20 @@ ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
        return 0;
 }
 
+static int
+mplsip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
+           u8 type, u8 code, int offset, __be32 info)
+{
+       __u32 rel_info = ntohl(info);
+       int err, rel_msg = 0;
+       u8 rel_type = type;
+       u8 rel_code = code;
+
+       err = ip6_tnl_err(skb, IPPROTO_MPLS, opt, &rel_type, &rel_code,
+                         &rel_msg, &rel_info, offset);
+       return err;
+}
+
 static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
                                       const struct ipv6hdr *ipv6h,
                                       struct sk_buff *skb)
@@ -740,6 +759,14 @@ static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
        return IP6_ECN_decapsulate(ipv6h, skb);
 }
 
+static inline int mplsip6_dscp_ecn_decapsulate(const struct ip6_tnl *t,
+                                              const struct ipv6hdr *ipv6h,
+                                              struct sk_buff *skb)
+{
+       /* ECN is not supported in AF_MPLS */
+       return 0;
+}
+
 __u32 ip6_tnl_get_cap(struct ip6_tnl *t,
                             const struct in6_addr *laddr,
                             const struct in6_addr *raddr)
@@ -901,6 +928,11 @@ static const struct tnl_ptk_info tpi_v4 = {
        .proto = htons(ETH_P_IP),
 };
 
+static const struct tnl_ptk_info tpi_mpls = {
+       /* no tunnel info required for mplsip6. */
+       .proto = htons(ETH_P_MPLS_UC),
+};
+
 static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
                      const struct tnl_ptk_info *tpi,
                      int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t,
@@ -958,6 +990,12 @@ static int ip6ip6_rcv(struct sk_buff *skb)
                          ip6ip6_dscp_ecn_decapsulate);
 }
 
+static int mplsip6_rcv(struct sk_buff *skb)
+{
+       return ipxip6_rcv(skb, IPPROTO_MPLS, &tpi_mpls,
+                         mplsip6_dscp_ecn_decapsulate);
+}
+
 struct ipv6_tel_txoption {
        struct ipv6_txoptions ops;
        __u8 dst_opt[8];
@@ -2198,6 +2236,12 @@ static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
        .priority       =       1,
 };
 
+static struct xfrm6_tunnel mplsip6_handler __read_mostly = {
+       .handler        = mplsip6_rcv,
+       .err_handler    = mplsip6_err,
+       .priority       =       1,
+};
+
 static void __net_exit ip6_tnl_destroy_tunnels(struct net *net, struct list_head *list)
 {
        struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
@@ -2312,6 +2356,15 @@ static int __init ip6_tunnel_init(void)
                pr_err("%s: can't register ip6ip6\n", __func__);
                goto out_ip6ip6;
        }
+
+       if (ip6_tnl_mpls_supported()) {
+               err = xfrm6_tunnel_register(&mplsip6_handler, AF_MPLS);
+               if (err < 0) {
+                       pr_err("%s: can't register mplsip6\n", __func__);
+                       goto out_mplsip6;
+               }
+       }
+
        err = rtnl_link_register(&ip6_link_ops);
        if (err < 0)
                goto rtnl_link_failed;
@@ -2319,6 +2372,9 @@ static int __init ip6_tunnel_init(void)
        return 0;
 
 rtnl_link_failed:
+       if (ip6_tnl_mpls_supported())
+               xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS);
+out_mplsip6:
        xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6);
 out_ip6ip6:
        xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET);
@@ -2341,6 +2397,9 @@ static void __exit ip6_tunnel_cleanup(void)
        if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6))
                pr_info("%s: can't deregister ip6ip6\n", __func__);
 
+       if (ip6_tnl_mpls_supported() &&
+           xfrm6_tunnel_deregister(&mplsip6_handler, AF_MPLS))
+               pr_info("%s: can't deregister mplsip6\n", __func__);
        unregister_pernet_device(&ip6_tnl_net_ops);
 }