geneve: allow user to specify TTL for tunnel frames

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index b7eafa4c1a673efa2672c1ae13ff599b6d389818..1675dfdbfa70b17e8d3df185d977d0baf4f49df8 100644 (file)
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -44,7 +44,8 @@ struct geneve_dev {
        struct net         *net;        /* netns for packet i/o */
        struct net_device  *dev;        /* netdev for geneve tunnel */
        struct geneve_sock *sock;       /* socket used for geneve tunnel */
-       u8 vni[3];                      /* virtual network ID for tunnel */
+       u8                 vni[3];      /* virtual network ID for tunnel */
+       u8                 ttl;         /* TTL override */
        struct sockaddr_in remote;      /* IPv4 address for link partner */
        struct list_head   next;        /* geneve's per namespace list */
 };
@@ -184,7 +185,7 @@ static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
        struct flowi4 fl4;
        int err;
        __be16 sport;
-       __u8 tos, ttl = 0;
+       __u8 tos, ttl;
 
        iip = ip_hdr(skb);
 
@@ -207,11 +208,12 @@ static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
                goto rt_tx_error;
        }
 
-       /* TODO: tos and ttl should be configurable */
+       /* TODO: tos should be configurable */
 
        tos = ip_tunnel_ecn_encap(0, iip, skb);
 
-       if (IN_MULTICAST(ntohl(fl4.daddr)))
+       ttl = geneve->ttl;
+       if (!ttl && IN_MULTICAST(ntohl(fl4.daddr)))
                ttl = 1;
 
        ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);
@@ -297,6 +299,7 @@ static void geneve_setup(struct net_device *dev)
 static const struct nla_policy geneve_policy[IFLA_GENEVE_MAX + 1] = {
        [IFLA_GENEVE_ID]                = { .type = NLA_U32 },
        [IFLA_GENEVE_REMOTE]            = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
+       [IFLA_GENEVE_TTL]               = { .type = NLA_U8 },
 };
 
 static int geneve_validate(struct nlattr *tb[], struct nlattr *data[])
@@ -364,6 +367,9 @@ static int geneve_newlink(struct net *net, struct net_device *dev,
        if (err)
                return err;
 
+       if (data[IFLA_GENEVE_TTL])
+               geneve->ttl = nla_get_u8(data[IFLA_GENEVE_TTL]);
+
        list_add(&geneve->next, &gn->geneve_list);
 
        hlist_add_head_rcu(&geneve->hlist, &gn->vni_list[hash]);
@@ -386,6 +392,7 @@ static size_t geneve_get_size(const struct net_device *dev)
 {
        return nla_total_size(sizeof(__u32)) +  /* IFLA_GENEVE_ID */
                nla_total_size(sizeof(struct in_addr)) + /* IFLA_GENEVE_REMOTE */
+               nla_total_size(sizeof(__u8)) +  /* IFLA_GENEVE_TTL */
                0;
 }
 
@@ -402,6 +409,9 @@ static int geneve_fill_info(struct sk_buff *skb, const struct net_device *dev)
                            geneve->remote.sin_addr.s_addr))
                goto nla_put_failure;
 
+       if (nla_put_u8(skb, IFLA_GENEVE_TTL, geneve->ttl))
+               goto nla_put_failure;
+
        return 0;
 
 nla_put_failure:

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index afccc9393fefbc987477fc1cbe6ec483b208707d..a834f31db9150883691c2f4674dd5607db72e044 100644 (file)
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -395,6 +395,7 @@ enum {
        IFLA_GENEVE_UNSPEC,
        IFLA_GENEVE_ID,
        IFLA_GENEVE_REMOTE,
+       IFLA_GENEVE_TTL,
        __IFLA_GENEVE_MAX
 };
 #define IFLA_GENEVE_MAX        (__IFLA_GENEVE_MAX - 1)