ipip: Setup and TX path for ipip/UDP foo-over-udp encapsulation

Add netlink handling for IP tunnel encapsulation parameters and
and adjustment of MTU for encapsulation.  ip_tunnel_encap is called
from ip_tunnel_xmit to actually perform FOU encapsulation.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 77 insertions, 1 deletions

diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 62eaa005e146..bfec31df8b21 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -301,7 +301,8 @@ static int ipip_tunnel_init(struct net_device *dev)
         memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
         memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
 
-        tunnel->hlen = 0;
+        tunnel->tun_hlen = 0;
+        tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen;
         tunnel->parms.iph.protocol = IPPROTO_IPIP;
         return ip_tunnel_init(dev);
 }
@@ -340,10 +341,53 @@ static void ipip_netlink_parms(struct nlattr *data[],
                 parms->iph.frag_off = htons(IP_DF);
 }
 
+/* This function returns true when ENCAP attributes are present in the nl msg */
+static bool ipip_netlink_encap_parms(struct nlattr *data[],
+                                     struct ip_tunnel_encap *ipencap)
+{
+        bool ret = false;
+
+        memset(ipencap, 0, sizeof(*ipencap));
+
+        if (!data)
+                return ret;
+
+        if (data[IFLA_IPTUN_ENCAP_TYPE]) {
+                ret = true;
+                ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
+        }
+
+        if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
+                ret = true;
+                ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
+        }
+
+        if (data[IFLA_IPTUN_ENCAP_SPORT]) {
+                ret = true;
+                ipencap->sport = nla_get_u16(data[IFLA_IPTUN_ENCAP_SPORT]);
+        }
+
+        if (data[IFLA_IPTUN_ENCAP_DPORT]) {
+                ret = true;
+                ipencap->dport = nla_get_u16(data[IFLA_IPTUN_ENCAP_DPORT]);
+        }
+
+        return ret;
+}
+
 static int ipip_newlink(struct net *src_net, struct net_device *dev,
                         struct nlattr *tb[], struct nlattr *data[])
 {
         struct ip_tunnel_parm p;
+        struct ip_tunnel_encap ipencap;
+
+        if (ipip_netlink_encap_parms(data, &ipencap)) {
+                struct ip_tunnel *t = netdev_priv(dev);
+                int err = ip_tunnel_encap_setup(t, &ipencap);
+
+                if (err < 0)
+                        return err;
+        }
 
         ipip_netlink_parms(data, &p);
         return ip_tunnel_newlink(dev, tb, &p);
@@ -353,6 +397,15 @@ static int ipip_changelink(struct net_device *dev, struct nlattr *tb[],
                            struct nlattr *data[])
 {
         struct ip_tunnel_parm p;
+        struct ip_tunnel_encap ipencap;
+
+        if (ipip_netlink_encap_parms(data, &ipencap)) {
+                struct ip_tunnel *t = netdev_priv(dev);
+                int err = ip_tunnel_encap_setup(t, &ipencap);
+
+                if (err < 0)
+                        return err;
+        }
 
         ipip_netlink_parms(data, &p);
 
@@ -378,6 +431,14 @@ static size_t ipip_get_size(const struct net_device *dev)
                 nla_total_size(1) +
                 /* IFLA_IPTUN_PMTUDISC */
                 nla_total_size(1) +
+                /* IFLA_IPTUN_ENCAP_TYPE */
+                nla_total_size(2) +
+                /* IFLA_IPTUN_ENCAP_FLAGS */
+                nla_total_size(2) +
+                /* IFLA_IPTUN_ENCAP_SPORT */
+                nla_total_size(2) +
+                /* IFLA_IPTUN_ENCAP_DPORT */
+                nla_total_size(2) +
                 0;
 }
 
@@ -394,6 +455,17 @@ static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev)
             nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
                        !!(parm->iph.frag_off & htons(IP_DF))))
                 goto nla_put_failure;
+
+        if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
+                        tunnel->encap.type) ||
+            nla_put_u16(skb, IFLA_IPTUN_ENCAP_SPORT,
+                        tunnel->encap.sport) ||
+            nla_put_u16(skb, IFLA_IPTUN_ENCAP_DPORT,
+                        tunnel->encap.dport) ||
+            nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
+                        tunnel->encap.dport))
+                goto nla_put_failure;
+
         return 0;
 
 nla_put_failure:
@@ -407,6 +479,10 @@ static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = {
         [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
         [IFLA_IPTUN_TOS]                = { .type = NLA_U8 },
         [IFLA_IPTUN_PMTUDISC]           = { .type = NLA_U8 },
+        [IFLA_IPTUN_ENCAP_TYPE]         = { .type = NLA_U16 },
+        [IFLA_IPTUN_ENCAP_FLAGS]        = { .type = NLA_U16 },
+        [IFLA_IPTUN_ENCAP_SPORT]        = { .type = NLA_U16 },
+        [IFLA_IPTUN_ENCAP_DPORT]        = { .type = NLA_U16 },
 };
 
 static struct rtnl_link_ops ipip_link_ops __read_mostly = {