[PATCH net-next v6 23/25] ovpn: notify userspace when a peer is deleted
From: Antonio Quartulli <antonio@openvpn.net>
Date: 2024-08-27 12:07:04
Subsystem:
networking drivers, openvpn data channel offload, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Antonio Quartulli, Linus Torvalds
Whenever a peer is deleted, send a notification to userspace so that it can react accordingly. This is most important when a peer is deleted due to ping timeout, because it all happens in kernelspace and thus userspace has no direct way to learn about it. Signed-off-by: Antonio Quartulli <antonio@openvpn.net> --- drivers/net/ovpn/netlink.c | 55 ++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/netlink.h | 1 + drivers/net/ovpn/peer.c | 1 + 3 files changed, 57 insertions(+)
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index 7cbad5a92b25..1933887ef281 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c@@ -911,6 +911,61 @@ int ovpn_nl_del_key_doit(struct sk_buff *skb, struct genl_info *info) return 0; } +/** + * ovpn_nl_notify_del_peer - notify userspace about peer being deleted + * @peer: the peer being deleted + * + * Return: 0 on success or a negative error code otherwise + */ +int ovpn_nl_notify_del_peer(struct ovpn_peer *peer) +{ + struct sk_buff *msg; + struct nlattr *attr; + int ret = -EMSGSIZE; + void *hdr; + + netdev_info(peer->ovpn->dev, "deleting peer with id %u, reason %d\n", + peer->id, peer->delete_reason); + + msg = nlmsg_new(100, GFP_ATOMIC); + if (!msg) + return -ENOMEM; + + hdr = genlmsg_put(msg, 0, 0, &ovpn_nl_family, 0, OVPN_CMD_DEL_PEER); + if (!hdr) { + ret = -ENOBUFS; + goto err_free_msg; + } + + if (nla_put_u32(msg, OVPN_A_IFINDEX, peer->ovpn->dev->ifindex)) + goto err_cancel_msg; + + attr = nla_nest_start(msg, OVPN_A_PEER); + if (!attr) + goto err_cancel_msg; + + if (nla_put_u8(msg, OVPN_A_PEER_DEL_REASON, peer->delete_reason)) + goto err_cancel_msg; + + if (nla_put_u32(msg, OVPN_A_PEER_ID, peer->id)) + goto err_cancel_msg; + + nla_nest_end(msg, attr); + + genlmsg_end(msg, hdr); + + genlmsg_multicast_netns(&ovpn_nl_family, dev_net(peer->ovpn->dev), msg, + 0, OVPN_NLGRP_PEERS, GFP_ATOMIC); + + return 0; + +err_cancel_msg: + genlmsg_cancel(msg, hdr); +err_free_msg: + nlmsg_free(msg); + return ret; +} + /** * ovpn_nl_notify_swap_keys - notify userspace peer's key must be renewed * @peer: the peer whose key needs to be renewed
diff --git a/drivers/net/ovpn/netlink.h b/drivers/net/ovpn/netlink.h
index 972d12fc8f93..5bb53bbd36d1 100644
--- a/drivers/net/ovpn/netlink.h
+++ b/drivers/net/ovpn/netlink.h@@ -12,6 +12,7 @@ int ovpn_nl_register(void); void ovpn_nl_unregister(void); +int ovpn_nl_notify_del_peer(struct ovpn_peer *peer); int ovpn_nl_notify_swap_keys(struct ovpn_peer *peer, u8 key_id); #endif /* _NET_OVPN_NETLINK_H_ */
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index c460a71dcc29..3fc64af4f22a 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c@@ -238,6 +238,7 @@ void ovpn_peer_release_kref(struct kref *kref) { struct ovpn_peer *peer = container_of(kref, struct ovpn_peer, refcount); + ovpn_nl_notify_del_peer(peer); ovpn_peer_release(peer); kfree_rcu(peer, rcu); }
--
2.44.2