sit: add support of link creation via rtnl

This patch add the support of 'ip link .. type sit'.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 150 insertions, 28 deletions

diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 17442dec06de..7bd2a061e511 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -216,6 +216,37 @@ static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn)
 #endif
 }
 
+static int ipip6_tunnel_create(struct net_device *dev)
+{
+        struct ip_tunnel *t = netdev_priv(dev);
+        struct net *net = dev_net(dev);
+        struct sit_net *sitn = net_generic(net, sit_net_id);
+        int err;
+
+        err = ipip6_tunnel_init(dev);
+        if (err < 0)
+                goto out;
+        ipip6_tunnel_clone_6rd(dev, sitn);
+
+        if (t->parms.i_flags & SIT_ISATAP)
+                dev->priv_flags |= IFF_ISATAP;
+
+        err = register_netdevice(dev);
+        if (err < 0)
+                goto out;
+
+        strcpy(t->parms.name, dev->name);
+        dev->rtnl_link_ops = &sit_link_ops;
+
+        dev_hold(dev);
+
+        ipip6_tunnel_link(sitn, t);
+        return 0;
+
+out:
+        return err;
+}
+
 static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
                 struct ip_tunnel_parm *parms, int create)
 {
@@ -256,22 +287,9 @@ static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
         nt = netdev_priv(dev);
 
         nt->parms = *parms;
-        if (ipip6_tunnel_init(dev) < 0)
-                goto failed_free;
-        ipip6_tunnel_clone_6rd(dev, sitn);
-
-        if (parms->i_flags & SIT_ISATAP)
-                dev->priv_flags |= IFF_ISATAP;
-
-        if (register_netdevice(dev) < 0)
+        if (ipip6_tunnel_create(dev) < 0)
                 goto failed_free;
 
-        strcpy(nt->parms.name, dev->name);
-        dev->rtnl_link_ops = &sit_link_ops;
-
-        dev_hold(dev);
-
-        ipip6_tunnel_link(sitn, nt);
         return nt;
 
 failed_free:
@@ -897,6 +915,27 @@ static void ipip6_tunnel_bind_dev(struct net_device *dev)
         dev->iflink = tunnel->parms.link;
 }
 
+static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm *p)
+{
+        struct net *net = dev_net(t->dev);
+        struct sit_net *sitn = net_generic(net, sit_net_id);
+
+        ipip6_tunnel_unlink(sitn, t);
+        synchronize_net();
+        t->parms.iph.saddr = p->iph.saddr;
+        t->parms.iph.daddr = p->iph.daddr;
+        memcpy(t->dev->dev_addr, &p->iph.saddr, 4);
+        memcpy(t->dev->broadcast, &p->iph.daddr, 4);
+        ipip6_tunnel_link(sitn, t);
+        t->parms.iph.ttl = p->iph.ttl;
+        t->parms.iph.tos = p->iph.tos;
+        if (t->parms.link != p->link) {
+                t->parms.link = p->link;
+                ipip6_tunnel_bind_dev(t->dev);
+        }
+        netdev_state_change(t->dev);
+}
+
 static int
 ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
 {
@@ -980,20 +1019,7 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
                                 t = netdev_priv(dev);
                         }
 
-                        ipip6_tunnel_unlink(sitn, t);
-                        synchronize_net();
-                        t->parms.iph.saddr = p.iph.saddr;
-                        t->parms.iph.daddr = p.iph.daddr;
-                        memcpy(dev->dev_addr, &p.iph.saddr, 4);
-                        memcpy(dev->broadcast, &p.iph.daddr, 4);
-                        ipip6_tunnel_link(sitn, t);
-                        t->parms.iph.ttl = p.iph.ttl;
-                        t->parms.iph.tos = p.iph.tos;
-                        if (t->parms.link != p.link) {
-                                t->parms.link = p.link;
-                                ipip6_tunnel_bind_dev(dev);
-                        }
-                        netdev_state_change(dev);
+                        ipip6_tunnel_update(t, &p);
                 }
 
                 if (t) {
@@ -1197,6 +1223,88 @@ static int __net_init ipip6_fb_tunnel_init(struct net_device *dev)
         return 0;
 }
 
+static void ipip6_netlink_parms(struct nlattr *data[],
+                                struct ip_tunnel_parm *parms)
+{
+        memset(parms, 0, sizeof(*parms));
+
+        parms->iph.version = 4;
+        parms->iph.protocol = IPPROTO_IPV6;
+        parms->iph.ihl = 5;
+        parms->iph.ttl = 64;
+
+        if (!data)
+                return;
+
+        if (data[IFLA_IPTUN_LINK])
+                parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
+
+        if (data[IFLA_IPTUN_LOCAL])
+                parms->iph.saddr = nla_get_u32(data[IFLA_IPTUN_LOCAL]);
+
+        if (data[IFLA_IPTUN_REMOTE])
+                parms->iph.daddr = nla_get_u32(data[IFLA_IPTUN_REMOTE]);
+
+        if (data[IFLA_IPTUN_TTL]) {
+                parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]);
+                if (parms->iph.ttl)
+                        parms->iph.frag_off = htons(IP_DF);
+        }
+
+        if (data[IFLA_IPTUN_TOS])
+                parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]);
+
+        if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC]))
+                parms->iph.frag_off = htons(IP_DF);
+
+        if (data[IFLA_IPTUN_FLAGS])
+                parms->i_flags = nla_get_u16(data[IFLA_IPTUN_FLAGS]);
+}
+
+static int ipip6_newlink(struct net *src_net, struct net_device *dev,
+                         struct nlattr *tb[], struct nlattr *data[])
+{
+        struct net *net = dev_net(dev);
+        struct ip_tunnel *nt;
+
+        nt = netdev_priv(dev);
+        ipip6_netlink_parms(data, &nt->parms);
+
+        if (ipip6_tunnel_locate(net, &nt->parms, 0))
+                return -EEXIST;
+
+        return ipip6_tunnel_create(dev);
+}
+
+static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[],
+                          struct nlattr *data[])
+{
+        struct ip_tunnel *t;
+        struct ip_tunnel_parm p;
+        struct net *net = dev_net(dev);
+        struct sit_net *sitn = net_generic(net, sit_net_id);
+
+        if (dev == sitn->fb_tunnel_dev)
+                return -EINVAL;
+
+        ipip6_netlink_parms(data, &p);
+
+        if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
+            (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
+                return -EINVAL;
+
+        t = ipip6_tunnel_locate(net, &p, 0);
+
+        if (t) {
+                if (t->dev != dev)
+                        return -EEXIST;
+        } else
+                t = netdev_priv(dev);
+
+        ipip6_tunnel_update(t, &p);
+        return 0;
+}
+
 static size_t ipip6_get_size(const struct net_device *dev)
 {
         return
@@ -1237,10 +1345,24 @@ nla_put_failure:
         return -EMSGSIZE;
 }
 
+static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = {
+        [IFLA_IPTUN_LINK]               = { .type = NLA_U32 },
+        [IFLA_IPTUN_LOCAL]              = { .type = NLA_U32 },
+        [IFLA_IPTUN_REMOTE]             = { .type = NLA_U32 },
+        [IFLA_IPTUN_TTL]                = { .type = NLA_U8 },
+        [IFLA_IPTUN_TOS]                = { .type = NLA_U8 },
+        [IFLA_IPTUN_PMTUDISC]           = { .type = NLA_U8 },
+        [IFLA_IPTUN_FLAGS]              = { .type = NLA_U16 },
+};
+
 static struct rtnl_link_ops sit_link_ops __read_mostly = {
         .kind           = "sit",
         .maxtype        = IFLA_IPTUN_MAX,
+        .policy         = ipip6_policy,
         .priv_size      = sizeof(struct ip_tunnel),
+        .setup          = ipip6_tunnel_setup,
+        .newlink        = ipip6_newlink,
+        .changelink     = ipip6_changelink,
         .get_size       = ipip6_get_size,
         .fill_info      = ipip6_fill_info,
 };