{
struct l2tp_tunnel *tunnel = NULL;
int err;
- struct socket *sock = NULL;
- struct sock *sk = NULL;
- struct l2tp_net *pn;
enum l2tp_encap_type encap = L2TP_ENCAPTYPE_UDP;
- /* Get the tunnel socket from the fd, which was opened by
- * the userspace L2TP daemon. If not specified, create a
- * kernel socket.
- */
- if (fd < 0) {
- err = l2tp_tunnel_sock_create(net, tunnel_id, peer_tunnel_id,
- cfg, &sock);
- if (err < 0)
- goto err;
- } else {
- sock = sockfd_lookup(fd, &err);
- if (!sock) {
- pr_err("tunl %u: sockfd_lookup(fd=%d) returned %d\n",
- tunnel_id, fd, err);
- err = -EBADF;
- goto err;
- }
-
- /* Reject namespace mismatches */
- if (!net_eq(sock_net(sock->sk), net)) {
- pr_err("tunl %u: netns mismatch\n", tunnel_id);
- err = -EINVAL;
- goto err;
- }
- }
-
- sk = sock->sk;
-
if (cfg != NULL)
encap = cfg->encap;
- /* Quick sanity checks */
- err = -EPROTONOSUPPORT;
- if (sk->sk_type != SOCK_DGRAM) {
- pr_debug("tunl %hu: fd %d wrong socket type\n",
- tunnel_id, fd);
- goto err;
- }
- switch (encap) {
- case L2TP_ENCAPTYPE_UDP:
- if (sk->sk_protocol != IPPROTO_UDP) {
- pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n",
- tunnel_id, fd, sk->sk_protocol, IPPROTO_UDP);
- goto err;
- }
- break;
- case L2TP_ENCAPTYPE_IP:
- if (sk->sk_protocol != IPPROTO_L2TP) {
- pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n",
- tunnel_id, fd, sk->sk_protocol, IPPROTO_L2TP);
- goto err;
- }
- break;
- }
-
- /* Check if this socket has already been prepped */
- tunnel = l2tp_tunnel(sk);
- if (tunnel != NULL) {
- /* This socket has already been prepped */
- err = -EBUSY;
- goto err;
- }
-
tunnel = kzalloc(sizeof(struct l2tp_tunnel), GFP_KERNEL);
if (tunnel == NULL) {
err = -ENOMEM;
rwlock_init(&tunnel->hlist_lock);
tunnel->acpt_newsess = true;
- /* The net we belong to */
- tunnel->l2tp_net = net;
- pn = l2tp_pernet(net);
-
if (cfg != NULL)
tunnel->debug = cfg->debug;
- /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */
tunnel->encap = encap;
- if (encap == L2TP_ENCAPTYPE_UDP) {
- struct udp_tunnel_sock_cfg udp_cfg = { };
-
- udp_cfg.sk_user_data = tunnel;
- udp_cfg.encap_type = UDP_ENCAP_L2TPINUDP;
- udp_cfg.encap_rcv = l2tp_udp_encap_recv;
- udp_cfg.encap_destroy = l2tp_udp_encap_destroy;
-
- setup_udp_tunnel_sock(net, sock, &udp_cfg);
- } else {
- sk->sk_user_data = tunnel;
- }
- /* Bump the reference count. The tunnel context is deleted
- * only when this drops to zero. A reference is also held on
- * the tunnel socket to ensure that it is not released while
- * the tunnel is extant. Must be done before sk_destruct is
- * set.
- */
refcount_set(&tunnel->ref_count, 1);
- sock_hold(sk);
- tunnel->sock = sk;
tunnel->fd = fd;
- /* Hook on the tunnel socket destructor so that we can cleanup
- * if the tunnel socket goes away.
- */
- tunnel->old_sk_destruct = sk->sk_destruct;
- sk->sk_destruct = &l2tp_tunnel_destruct;
- lockdep_set_class_and_name(&sk->sk_lock.slock, &l2tp_socket_class, "l2tp_sock");
-
- sk->sk_allocation = GFP_ATOMIC;
-
/* Init delete workqueue struct */
INIT_WORK(&tunnel->del_work, l2tp_tunnel_del_work);
- /* Add tunnel to our list */
INIT_LIST_HEAD(&tunnel->list);
- spin_lock_bh(&pn->l2tp_tunnel_list_lock);
- list_add_rcu(&tunnel->list, &pn->l2tp_tunnel_list);
- spin_unlock_bh(&pn->l2tp_tunnel_list_lock);
err = 0;
err:
if (tunnelp)
*tunnelp = tunnel;
- /* If tunnel's socket was created by the kernel, it doesn't
- * have a file.
- */
- if (sock && sock->file)
- sockfd_put(sock);
-
return err;
}
EXPORT_SYMBOL_GPL(l2tp_tunnel_create);
+static int l2tp_validate_socket(const struct sock *sk, const struct net *net,
+ enum l2tp_encap_type encap)
+{
+ if (!net_eq(sock_net(sk), net))
+ return -EINVAL;
+
+ if (sk->sk_type != SOCK_DGRAM)
+ return -EPROTONOSUPPORT;
+
+ if ((encap == L2TP_ENCAPTYPE_UDP && sk->sk_protocol != IPPROTO_UDP) ||
+ (encap == L2TP_ENCAPTYPE_IP && sk->sk_protocol != IPPROTO_L2TP))
+ return -EPROTONOSUPPORT;
+
+ if (sk->sk_user_data)
+ return -EBUSY;
+
+ return 0;
+}
+
+int l2tp_tunnel_register(struct l2tp_tunnel *tunnel, struct net *net,
+ struct l2tp_tunnel_cfg *cfg)
+{
+ struct l2tp_net *pn;
+ struct socket *sock;
+ struct sock *sk;
+ int ret;
+
+ if (tunnel->fd < 0) {
+ ret = l2tp_tunnel_sock_create(net, tunnel->tunnel_id,
+ tunnel->peer_tunnel_id, cfg,
+ &sock);
+ if (ret < 0)
+ goto err;
+ } else {
+ sock = sockfd_lookup(tunnel->fd, &ret);
+ if (!sock)
+ goto err;
+
+ ret = l2tp_validate_socket(sock->sk, net, tunnel->encap);
+ if (ret < 0)
+ goto err_sock;
+ }
+
+ sk = sock->sk;
+
+ sock_hold(sk);
+ tunnel->sock = sk;
+ tunnel->l2tp_net = net;
+
+ pn = l2tp_pernet(net);
+ spin_lock_bh(&pn->l2tp_tunnel_list_lock);
+ list_add_rcu(&tunnel->list, &pn->l2tp_tunnel_list);
+ spin_unlock_bh(&pn->l2tp_tunnel_list_lock);
+
+ if (tunnel->encap == L2TP_ENCAPTYPE_UDP) {
+ struct udp_tunnel_sock_cfg udp_cfg = {
+ .sk_user_data = tunnel,
+ .encap_type = UDP_ENCAP_L2TPINUDP,
+ .encap_rcv = l2tp_udp_encap_recv,
+ .encap_destroy = l2tp_udp_encap_destroy,
+ };
+
+ setup_udp_tunnel_sock(net, sock, &udp_cfg);
+ } else {
+ sk->sk_user_data = tunnel;
+ }
+
+ tunnel->old_sk_destruct = sk->sk_destruct;
+ sk->sk_destruct = &l2tp_tunnel_destruct;
+ lockdep_set_class_and_name(&sk->sk_lock.slock, &l2tp_socket_class,
+ "l2tp_sock");
+ sk->sk_allocation = GFP_ATOMIC;
+
+ if (tunnel->fd >= 0)
+ sockfd_put(sock);
+
+ return 0;
+
+err_sock:
+ sockfd_put(sock);
+err:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(l2tp_tunnel_register);
+
/* This function is used by the netlink TUNNEL_DELETE command.
*/
void l2tp_tunnel_delete(struct l2tp_tunnel *tunnel)
projects / linux / blobdiff