[PATCH net-next v8 05/24] ovpn: implement interface creation/destruction via netlink

[Antonio Quartulli]

Allow userspace to create and destroy an interface using netlink
commands.

Signed-off-by: Antonio Quartulli <anto...@openvpn.net>
---
 drivers/net/ovpn/main.h    |  2 ++
 drivers/net/ovpn/netlink.c | 59 ++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ovpn/main.h b/drivers/net/ovpn/main.h
index 
4dfcba9deb590bbf119f51a40dff1517fe227b22..c664d9c655734263fcf58dd8f2fa5446565a29cf
 100644
--- a/drivers/net/ovpn/main.h
+++ b/drivers/net/ovpn/main.h
@@ -10,6 +10,8 @@
 #ifndef _NET_OVPN_MAIN_H_
 #define _NET_OVPN_MAIN_H_
 
+#define OVPN_DEFAULT_IFNAME "ovpn%d"
+
 struct net_device *ovpn_iface_create(const char *name, enum ovpn_mode mode,
                                     struct net *net);
 void ovpn_iface_destruct(struct ovpn_struct *ovpn);
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index 
7b6b4d03b845eeb8654e37ac3495e8172ac3f291..6e60591d605dde19c6bbd47ef0e90e522776688c
 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -7,6 +7,7 @@
  */
 
 #include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
 #include <net/genetlink.h>
 
 #include <uapi/linux/ovpn.h>
@@ -84,12 +85,66 @@ void ovpn_nl_post_doit(const struct genl_split_ops *ops, 
struct sk_buff *skb,
 
 int ovpn_nl_dev_new_doit(struct sk_buff *skb, struct genl_info *info)
 {
-       return -EOPNOTSUPP;
+       const char *ifname = OVPN_DEFAULT_IFNAME;
+       enum ovpn_mode mode = OVPN_MODE_P2P;
+       struct net_device *dev;
+       struct sk_buff *msg;
+       void *hdr;
+
+       if (info->attrs[OVPN_A_IFNAME])
+               ifname = nla_data(info->attrs[OVPN_A_IFNAME]);
+
+       if (info->attrs[OVPN_A_MODE]) {
+               mode = nla_get_u32(info->attrs[OVPN_A_MODE]);
+               pr_debug("ovpn: setting device (%s) mode: %u\n", ifname, mode);
+       }
+
+       dev = ovpn_iface_create(ifname, mode, genl_info_net(info));
+       if (IS_ERR(dev)) {
+               NL_SET_ERR_MSG_FMT_MOD(info->extack,
+                                      "error while creating interface: %ld",
+                                      PTR_ERR(dev));
+               return PTR_ERR(dev);
+       }
+
+       msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+       if (!msg)
+               return -ENOMEM;
+
+       hdr = genlmsg_iput(msg, info);
+       if (!hdr) {
+               nlmsg_free(msg);
+               return -ENOBUFS;
+       }
+
+       if (nla_put_string(msg, OVPN_A_IFNAME, dev->name)) {
+               genlmsg_cancel(msg, hdr);
+               nlmsg_free(msg);
+               return -EMSGSIZE;
+       }
+
+       if (nla_put_u32(msg, OVPN_A_IFINDEX, dev->ifindex)) {
+               genlmsg_cancel(msg, hdr);
+               nlmsg_free(msg);
+               return -EMSGSIZE;
+       }
+
+       genlmsg_end(msg, hdr);
+
+       return genlmsg_reply(msg, info);
 }
 
 int ovpn_nl_dev_del_doit(struct sk_buff *skb, struct genl_info *info)
 {
-       return -EOPNOTSUPP;
+       struct ovpn_struct *ovpn = info->user_ptr[0];
+
+       rtnl_lock();
+       ovpn_iface_destruct(ovpn);
+       unregister_netdevice(ovpn->dev);
+       netdev_put(ovpn->dev, NULL);
+       rtnl_unlock();
+
+       return 0;
 }
 
 int ovpn_nl_peer_new_doit(struct sk_buff *skb, struct genl_info *info)

-- 
2.45.2