[Feature] add GA346 baseline version
Change-Id: Ic62933698569507dcf98240cdf5d9931ae34348f
diff --git a/src/kernel/linux/v4.19/net/l2tp/l2tp_ppp.c b/src/kernel/linux/v4.19/net/l2tp/l2tp_ppp.c
new file mode 100644
index 0000000..c095678
--- /dev/null
+++ b/src/kernel/linux/v4.19/net/l2tp/l2tp_ppp.c
@@ -0,0 +1,1765 @@
+/*****************************************************************************
+ * Linux PPP over L2TP (PPPoX/PPPoL2TP) Sockets
+ *
+ * PPPoX --- Generic PPP encapsulation socket family
+ * PPPoL2TP --- PPP over L2TP (RFC 2661)
+ *
+ * Version: 2.0.0
+ *
+ * Authors: James Chapman (jchapman@katalix.com)
+ *
+ * Based on original work by Martijn van Oosterhout <kleptog@svana.org>
+ *
+ * License:
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+/* This driver handles only L2TP data frames; control frames are handled by a
+ * userspace application.
+ *
+ * To send data in an L2TP session, userspace opens a PPPoL2TP socket and
+ * attaches it to a bound UDP socket with local tunnel_id / session_id and
+ * peer tunnel_id / session_id set. Data can then be sent or received using
+ * regular socket sendmsg() / recvmsg() calls. Kernel parameters of the socket
+ * can be read or modified using ioctl() or [gs]etsockopt() calls.
+ *
+ * When a PPPoL2TP socket is connected with local and peer session_id values
+ * zero, the socket is treated as a special tunnel management socket.
+ *
+ * Here's example userspace code to create a socket for sending/receiving data
+ * over an L2TP session:-
+ *
+ * struct sockaddr_pppol2tp sax;
+ * int fd;
+ * int session_fd;
+ *
+ * fd = socket(AF_PPPOX, SOCK_DGRAM, PX_PROTO_OL2TP);
+ *
+ * sax.sa_family = AF_PPPOX;
+ * sax.sa_protocol = PX_PROTO_OL2TP;
+ * sax.pppol2tp.fd = tunnel_fd; // bound UDP socket
+ * sax.pppol2tp.addr.sin_addr.s_addr = addr->sin_addr.s_addr;
+ * sax.pppol2tp.addr.sin_port = addr->sin_port;
+ * sax.pppol2tp.addr.sin_family = AF_INET;
+ * sax.pppol2tp.s_tunnel = tunnel_id;
+ * sax.pppol2tp.s_session = session_id;
+ * sax.pppol2tp.d_tunnel = peer_tunnel_id;
+ * sax.pppol2tp.d_session = peer_session_id;
+ *
+ * session_fd = connect(fd, (struct sockaddr *)&sax, sizeof(sax));
+ *
+ * A pppd plugin that allows PPP traffic to be carried over L2TP using
+ * this driver is available from the OpenL2TP project at
+ * http://openl2tp.sourceforge.net.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/list.h>
+#include <linux/uaccess.h>
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/kthread.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/jiffies.h>
+
+#include <linux/netdevice.h>
+#include <linux/net.h>
+#include <linux/inetdevice.h>
+#include <linux/skbuff.h>
+#include <linux/init.h>
+#include <linux/ip.h>
+#include <linux/udp.h>
+#include <linux/if_pppox.h>
+#include <linux/if_pppol2tp.h>
+#include <net/sock.h>
+#include <linux/ppp_channel.h>
+#include <linux/ppp_defs.h>
+#include <linux/ppp-ioctl.h>
+#include <linux/file.h>
+#include <linux/hash.h>
+#include <linux/sort.h>
+#include <linux/proc_fs.h>
+#include <linux/l2tp.h>
+#include <linux/nsproxy.h>
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+#include <net/ip.h>
+#include <net/udp.h>
+#include <net/inet_common.h>
+
+#include <asm/byteorder.h>
+#include <linux/atomic.h>
+
+#include "l2tp_core.h"
+
+#define PPPOL2TP_DRV_VERSION "V2.0"
+
+/* Space for UDP, L2TP and PPP headers */
+#define PPPOL2TP_HEADER_OVERHEAD 40
+
+/* Number of bytes to build transmit L2TP headers.
+ * Unfortunately the size is different depending on whether sequence numbers
+ * are enabled.
+ */
+#define PPPOL2TP_L2TP_HDR_SIZE_SEQ 10
+#define PPPOL2TP_L2TP_HDR_SIZE_NOSEQ 6
+
+/* Private data of each session. This data lives at the end of struct
+ * l2tp_session, referenced via session->priv[].
+ */
+struct pppol2tp_session {
+ int owner; /* pid that opened the socket */
+
+ struct mutex sk_lock; /* Protects .sk */
+ struct sock __rcu *sk; /* Pointer to the session
+ * PPPoX socket */
+ struct sock *__sk; /* Copy of .sk, for cleanup */
+ struct rcu_head rcu; /* For asynchronous release */
+};
+
+static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb);
+
+static const struct ppp_channel_ops pppol2tp_chan_ops = {
+ .start_xmit = pppol2tp_xmit,
+};
+
+static const struct proto_ops pppol2tp_ops;
+
+/* Retrieves the pppol2tp socket associated to a session.
+ * A reference is held on the returned socket, so this function must be paired
+ * with sock_put().
+ */
+static struct sock *pppol2tp_session_get_sock(struct l2tp_session *session)
+{
+ struct pppol2tp_session *ps = l2tp_session_priv(session);
+ struct sock *sk;
+
+ rcu_read_lock();
+ sk = rcu_dereference(ps->sk);
+ if (sk)
+ sock_hold(sk);
+ rcu_read_unlock();
+
+ return sk;
+}
+
+/* Helpers to obtain tunnel/session contexts from sockets.
+ */
+static inline struct l2tp_session *pppol2tp_sock_to_session(struct sock *sk)
+{
+ struct l2tp_session *session;
+
+ if (sk == NULL)
+ return NULL;
+
+ sock_hold(sk);
+ session = (struct l2tp_session *)(sk->sk_user_data);
+ if (session == NULL) {
+ sock_put(sk);
+ goto out;
+ }
+
+ BUG_ON(session->magic != L2TP_SESSION_MAGIC);
+
+out:
+ return session;
+}
+
+/*****************************************************************************
+ * Receive data handling
+ *****************************************************************************/
+
+/* Receive message. This is the recvmsg for the PPPoL2TP socket.
+ */
+static int pppol2tp_recvmsg(struct socket *sock, struct msghdr *msg,
+ size_t len, int flags)
+{
+ int err;
+ struct sk_buff *skb;
+ struct sock *sk = sock->sk;
+
+ err = -EIO;
+ if (sk->sk_state & PPPOX_BOUND)
+ goto end;
+
+ err = 0;
+ skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
+ flags & MSG_DONTWAIT, &err);
+ if (!skb)
+ goto end;
+
+ if (len > skb->len)
+ len = skb->len;
+ else if (len < skb->len)
+ msg->msg_flags |= MSG_TRUNC;
+
+ err = skb_copy_datagram_msg(skb, 0, msg, len);
+ if (likely(err == 0))
+ err = len;
+
+ kfree_skb(skb);
+end:
+ return err;
+}
+
+static void pppol2tp_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
+{
+ struct pppol2tp_session *ps = l2tp_session_priv(session);
+ struct sock *sk = NULL;
+
+ /* If the socket is bound, send it in to PPP's input queue. Otherwise
+ * queue it on the session socket.
+ */
+ rcu_read_lock();
+ sk = rcu_dereference(ps->sk);
+ if (sk == NULL)
+ goto no_sock;
+
+ /* If the first two bytes are 0xFF03, consider that it is the PPP's
+ * Address and Control fields and skip them. The L2TP module has always
+ * worked this way, although, in theory, the use of these fields should
+ * be negociated and handled at the PPP layer. These fields are
+ * constant: 0xFF is the All-Stations Address and 0x03 the Unnumbered
+ * Information command with Poll/Final bit set to zero (RFC 1662).
+ */
+ if (pskb_may_pull(skb, 2) && skb->data[0] == PPP_ALLSTATIONS &&
+ skb->data[1] == PPP_UI)
+ skb_pull(skb, 2);
+
+ if (sk->sk_state & PPPOX_BOUND) {
+ struct pppox_sock *po;
+
+ l2tp_dbg(session, L2TP_MSG_DATA,
+ "%s: recv %d byte data frame, passing to ppp\n",
+ session->name, data_len);
+
+ po = pppox_sk(sk);
+ ppp_input(&po->chan, skb);
+ } else {
+ l2tp_dbg(session, L2TP_MSG_DATA,
+ "%s: recv %d byte data frame, passing to L2TP socket\n",
+ session->name, data_len);
+
+ if (sock_queue_rcv_skb(sk, skb) < 0) {
+ atomic_long_inc(&session->stats.rx_errors);
+ kfree_skb(skb);
+ }
+ }
+ rcu_read_unlock();
+
+ return;
+
+no_sock:
+ rcu_read_unlock();
+ l2tp_info(session, L2TP_MSG_DATA, "%s: no socket\n", session->name);
+ kfree_skb(skb);
+}
+
+/************************************************************************
+ * Transmit handling
+ ***********************************************************************/
+
+/* This is the sendmsg for the PPPoL2TP pppol2tp_session socket. We come here
+ * when a user application does a sendmsg() on the session socket. L2TP and
+ * PPP headers must be inserted into the user's data.
+ */
+static int pppol2tp_sendmsg(struct socket *sock, struct msghdr *m,
+ size_t total_len)
+{
+ struct sock *sk = sock->sk;
+ struct sk_buff *skb;
+ int error;
+ struct l2tp_session *session;
+ struct l2tp_tunnel *tunnel;
+ int uhlen;
+
+ error = -ENOTCONN;
+ if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
+ goto error;
+
+ /* Get session and tunnel contexts */
+ error = -EBADF;
+ session = pppol2tp_sock_to_session(sk);
+ if (session == NULL)
+ goto error;
+
+ tunnel = session->tunnel;
+
+ uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
+
+ /* Allocate a socket buffer */
+ error = -ENOMEM;
+ skb = sock_wmalloc(sk, NET_SKB_PAD + sizeof(struct iphdr) +
+ uhlen + session->hdr_len +
+ 2 + total_len, /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */
+ 0, GFP_KERNEL);
+ if (!skb)
+ goto error_put_sess;
+
+ /* Reserve space for headers. */
+ skb_reserve(skb, NET_SKB_PAD);
+ skb_reset_network_header(skb);
+ skb_reserve(skb, sizeof(struct iphdr));
+ skb_reset_transport_header(skb);
+ skb_reserve(skb, uhlen);
+
+ /* Add PPP header */
+ skb->data[0] = PPP_ALLSTATIONS;
+ skb->data[1] = PPP_UI;
+ skb_put(skb, 2);
+
+ /* Copy user data into skb */
+ error = memcpy_from_msg(skb_put(skb, total_len), m, total_len);
+ if (error < 0) {
+ kfree_skb(skb);
+ goto error_put_sess;
+ }
+
+ local_bh_disable();
+ l2tp_xmit_skb(session, skb, session->hdr_len);
+ local_bh_enable();
+
+ sock_put(sk);
+
+ return total_len;
+
+error_put_sess:
+ sock_put(sk);
+error:
+ return error;
+}
+
+/* Transmit function called by generic PPP driver. Sends PPP frame
+ * over PPPoL2TP socket.
+ *
+ * This is almost the same as pppol2tp_sendmsg(), but rather than
+ * being called with a msghdr from userspace, it is called with a skb
+ * from the kernel.
+ *
+ * The supplied skb from ppp doesn't have enough headroom for the
+ * insertion of L2TP, UDP and IP headers so we need to allocate more
+ * headroom in the skb. This will create a cloned skb. But we must be
+ * careful in the error case because the caller will expect to free
+ * the skb it supplied, not our cloned skb. So we take care to always
+ * leave the original skb unfreed if we return an error.
+ */
+static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
+{
+ struct sock *sk = (struct sock *) chan->private;
+ struct l2tp_session *session;
+ struct l2tp_tunnel *tunnel;
+ int uhlen, headroom;
+
+ if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
+ goto abort;
+
+ /* Get session and tunnel contexts from the socket */
+ session = pppol2tp_sock_to_session(sk);
+ if (session == NULL)
+ goto abort;
+
+ tunnel = session->tunnel;
+
+ uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0;
+ headroom = NET_SKB_PAD +
+ sizeof(struct iphdr) + /* IP header */
+ uhlen + /* UDP header (if L2TP_ENCAPTYPE_UDP) */
+ session->hdr_len + /* L2TP header */
+ 2; /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */
+ if (skb_cow_head(skb, headroom))
+ goto abort_put_sess;
+
+ /* Setup PPP header */
+ __skb_push(skb, 2);
+ skb->data[0] = PPP_ALLSTATIONS;
+ skb->data[1] = PPP_UI;
+
+ local_bh_disable();
+ l2tp_xmit_skb(session, skb, session->hdr_len);
+ local_bh_enable();
+
+ sock_put(sk);
+
+ return 1;
+
+abort_put_sess:
+ sock_put(sk);
+abort:
+ /* Free the original skb */
+ kfree_skb(skb);
+ return 1;
+}
+
+/*****************************************************************************
+ * Session (and tunnel control) socket create/destroy.
+ *****************************************************************************/
+
+static void pppol2tp_put_sk(struct rcu_head *head)
+{
+ struct pppol2tp_session *ps;
+
+ ps = container_of(head, typeof(*ps), rcu);
+ sock_put(ps->__sk);
+}
+
+/* Really kill the session socket. (Called from sock_put() if
+ * refcnt == 0.)
+ */
+static void pppol2tp_session_destruct(struct sock *sk)
+{
+ struct l2tp_session *session = sk->sk_user_data;
+
+ skb_queue_purge(&sk->sk_receive_queue);
+ skb_queue_purge(&sk->sk_write_queue);
+
+ if (session) {
+ sk->sk_user_data = NULL;
+ BUG_ON(session->magic != L2TP_SESSION_MAGIC);
+ l2tp_session_dec_refcount(session);
+ }
+}
+
+/* Called when the PPPoX socket (session) is closed.
+ */
+static int pppol2tp_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct l2tp_session *session;
+ int error;
+
+ if (!sk)
+ return 0;
+
+ error = -EBADF;
+ lock_sock(sk);
+ if (sock_flag(sk, SOCK_DEAD) != 0)
+ goto error;
+
+ pppox_unbind_sock(sk);
+
+ /* Signal the death of the socket. */
+ sk->sk_state = PPPOX_DEAD;
+ sock_orphan(sk);
+ sock->sk = NULL;
+
+ session = pppol2tp_sock_to_session(sk);
+ if (session) {
+ struct pppol2tp_session *ps;
+
+ l2tp_session_delete(session);
+
+ ps = l2tp_session_priv(session);
+ mutex_lock(&ps->sk_lock);
+ ps->__sk = rcu_dereference_protected(ps->sk,
+ lockdep_is_held(&ps->sk_lock));
+ RCU_INIT_POINTER(ps->sk, NULL);
+ mutex_unlock(&ps->sk_lock);
+ call_rcu(&ps->rcu, pppol2tp_put_sk);
+
+ /* Rely on the sock_put() call at the end of the function for
+ * dropping the reference held by pppol2tp_sock_to_session().
+ * The last reference will be dropped by pppol2tp_put_sk().
+ */
+ }
+
+ release_sock(sk);
+
+ /* This will delete the session context via
+ * pppol2tp_session_destruct() if the socket's refcnt drops to
+ * zero.
+ */
+ sock_put(sk);
+
+ return 0;
+
+error:
+ release_sock(sk);
+ return error;
+}
+
+static struct proto pppol2tp_sk_proto = {
+ .name = "PPPOL2TP",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct pppox_sock),
+};
+
+static int pppol2tp_backlog_recv(struct sock *sk, struct sk_buff *skb)
+{
+ int rc;
+
+ rc = l2tp_udp_encap_recv(sk, skb);
+ if (rc)
+ kfree_skb(skb);
+
+ return NET_RX_SUCCESS;
+}
+
+/* socket() handler. Initialize a new struct sock.
+ */
+static int pppol2tp_create(struct net *net, struct socket *sock, int kern)
+{
+ int error = -ENOMEM;
+ struct sock *sk;
+
+ sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppol2tp_sk_proto, kern);
+ if (!sk)
+ goto out;
+
+ sock_init_data(sock, sk);
+
+ sock->state = SS_UNCONNECTED;
+ sock->ops = &pppol2tp_ops;
+
+ sk->sk_backlog_rcv = pppol2tp_backlog_recv;
+ sk->sk_protocol = PX_PROTO_OL2TP;
+ sk->sk_family = PF_PPPOX;
+ sk->sk_state = PPPOX_NONE;
+ sk->sk_type = SOCK_STREAM;
+ sk->sk_destruct = pppol2tp_session_destruct;
+
+ error = 0;
+
+out:
+ return error;
+}
+
+static void pppol2tp_show(struct seq_file *m, void *arg)
+{
+ struct l2tp_session *session = arg;
+ struct sock *sk;
+
+ sk = pppol2tp_session_get_sock(session);
+ if (sk) {
+ struct pppox_sock *po = pppox_sk(sk);
+
+ seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
+ sock_put(sk);
+ }
+}
+
+static void pppol2tp_session_init(struct l2tp_session *session)
+{
+ struct pppol2tp_session *ps;
+
+ session->recv_skb = pppol2tp_recv;
+ if (IS_ENABLED(CONFIG_L2TP_DEBUGFS))
+ session->show = pppol2tp_show;
+
+ ps = l2tp_session_priv(session);
+ mutex_init(&ps->sk_lock);
+ ps->owner = current->pid;
+}
+
+struct l2tp_connect_info {
+ u8 version;
+ int fd;
+ u32 tunnel_id;
+ u32 peer_tunnel_id;
+ u32 session_id;
+ u32 peer_session_id;
+};
+
+static int pppol2tp_sockaddr_get_info(const void *sa, int sa_len,
+ struct l2tp_connect_info *info)
+{
+ switch (sa_len) {
+ case sizeof(struct sockaddr_pppol2tp):
+ {
+ const struct sockaddr_pppol2tp *sa_v2in4 = sa;
+
+ if (sa_v2in4->sa_protocol != PX_PROTO_OL2TP)
+ return -EINVAL;
+
+ info->version = 2;
+ info->fd = sa_v2in4->pppol2tp.fd;
+ info->tunnel_id = sa_v2in4->pppol2tp.s_tunnel;
+ info->peer_tunnel_id = sa_v2in4->pppol2tp.d_tunnel;
+ info->session_id = sa_v2in4->pppol2tp.s_session;
+ info->peer_session_id = sa_v2in4->pppol2tp.d_session;
+
+ break;
+ }
+ case sizeof(struct sockaddr_pppol2tpv3):
+ {
+ const struct sockaddr_pppol2tpv3 *sa_v3in4 = sa;
+
+ if (sa_v3in4->sa_protocol != PX_PROTO_OL2TP)
+ return -EINVAL;
+
+ info->version = 3;
+ info->fd = sa_v3in4->pppol2tp.fd;
+ info->tunnel_id = sa_v3in4->pppol2tp.s_tunnel;
+ info->peer_tunnel_id = sa_v3in4->pppol2tp.d_tunnel;
+ info->session_id = sa_v3in4->pppol2tp.s_session;
+ info->peer_session_id = sa_v3in4->pppol2tp.d_session;
+
+ break;
+ }
+ case sizeof(struct sockaddr_pppol2tpin6):
+ {
+ const struct sockaddr_pppol2tpin6 *sa_v2in6 = sa;
+
+ if (sa_v2in6->sa_protocol != PX_PROTO_OL2TP)
+ return -EINVAL;
+
+ info->version = 2;
+ info->fd = sa_v2in6->pppol2tp.fd;
+ info->tunnel_id = sa_v2in6->pppol2tp.s_tunnel;
+ info->peer_tunnel_id = sa_v2in6->pppol2tp.d_tunnel;
+ info->session_id = sa_v2in6->pppol2tp.s_session;
+ info->peer_session_id = sa_v2in6->pppol2tp.d_session;
+
+ break;
+ }
+ case sizeof(struct sockaddr_pppol2tpv3in6):
+ {
+ const struct sockaddr_pppol2tpv3in6 *sa_v3in6 = sa;
+
+ if (sa_v3in6->sa_protocol != PX_PROTO_OL2TP)
+ return -EINVAL;
+
+ info->version = 3;
+ info->fd = sa_v3in6->pppol2tp.fd;
+ info->tunnel_id = sa_v3in6->pppol2tp.s_tunnel;
+ info->peer_tunnel_id = sa_v3in6->pppol2tp.d_tunnel;
+ info->session_id = sa_v3in6->pppol2tp.s_session;
+ info->peer_session_id = sa_v3in6->pppol2tp.d_session;
+
+ break;
+ }
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/* Rough estimation of the maximum payload size a tunnel can transmit without
+ * fragmenting at the lower IP layer. Assumes L2TPv2 with sequence
+ * numbers and no IP option. Not quite accurate, but the result is mostly
+ * unused anyway.
+ */
+static int pppol2tp_tunnel_mtu(const struct l2tp_tunnel *tunnel)
+{
+ int mtu;
+
+ mtu = l2tp_tunnel_dst_mtu(tunnel);
+ if (mtu <= PPPOL2TP_HEADER_OVERHEAD)
+ return 1500 - PPPOL2TP_HEADER_OVERHEAD;
+
+ return mtu - PPPOL2TP_HEADER_OVERHEAD;
+}
+
+/* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
+ */
+static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
+ int sockaddr_len, int flags)
+{
+ struct sock *sk = sock->sk;
+ struct pppox_sock *po = pppox_sk(sk);
+ struct l2tp_session *session = NULL;
+ struct l2tp_connect_info info;
+ struct l2tp_tunnel *tunnel;
+ struct pppol2tp_session *ps;
+ struct l2tp_session_cfg cfg = { 0, };
+ bool drop_refcnt = false;
+ bool drop_tunnel = false;
+ bool new_session = false;
+ bool new_tunnel = false;
+ int error;
+
+ error = pppol2tp_sockaddr_get_info(uservaddr, sockaddr_len, &info);
+ if (error < 0)
+ return error;
+
+ lock_sock(sk);
+
+ /* Check for already bound sockets */
+ error = -EBUSY;
+ if (sk->sk_state & PPPOX_CONNECTED)
+ goto end;
+
+ /* We don't supporting rebinding anyway */
+ error = -EALREADY;
+ if (sk->sk_user_data)
+ goto end; /* socket is already attached */
+
+ /* Don't bind if tunnel_id is 0 */
+ error = -EINVAL;
+ if (!info.tunnel_id)
+ goto end;
+
+ tunnel = l2tp_tunnel_get(sock_net(sk), info.tunnel_id);
+ if (tunnel)
+ drop_tunnel = true;
+
+ /* Special case: create tunnel context if session_id and
+ * peer_session_id is 0. Otherwise look up tunnel using supplied
+ * tunnel id.
+ */
+ if (!info.session_id && !info.peer_session_id) {
+ if (tunnel == NULL) {
+ struct l2tp_tunnel_cfg tcfg = {
+ .encap = L2TP_ENCAPTYPE_UDP,
+ .debug = 0,
+ };
+
+ /* Prevent l2tp_tunnel_register() from trying to set up
+ * a kernel socket.
+ */
+ if (info.fd < 0) {
+ error = -EBADF;
+ goto end;
+ }
+
+ error = l2tp_tunnel_create(sock_net(sk), info.fd,
+ info.version,
+ info.tunnel_id,
+ info.peer_tunnel_id, &tcfg,
+ &tunnel);
+ if (error < 0)
+ goto end;
+
+ l2tp_tunnel_inc_refcount(tunnel);
+ error = l2tp_tunnel_register(tunnel, sock_net(sk),
+ &tcfg);
+ if (error < 0) {
+ kfree(tunnel);
+ goto end;
+ }
+ drop_tunnel = true;
+ new_tunnel = true;
+ }
+ } else {
+ /* Error if we can't find the tunnel */
+ error = -ENOENT;
+ if (tunnel == NULL)
+ goto end;
+
+ /* Error if socket is not prepped */
+ if (tunnel->sock == NULL)
+ goto end;
+ }
+
+ if (tunnel->peer_tunnel_id == 0)
+ tunnel->peer_tunnel_id = info.peer_tunnel_id;
+
+ session = l2tp_tunnel_get_session(tunnel, info.session_id);
+ if (session) {
+ drop_refcnt = true;
+
+ if (session->pwtype != L2TP_PWTYPE_PPP) {
+ error = -EPROTOTYPE;
+ goto end;
+ }
+
+ ps = l2tp_session_priv(session);
+
+ /* Using a pre-existing session is fine as long as it hasn't
+ * been connected yet.
+ */
+ mutex_lock(&ps->sk_lock);
+ if (rcu_dereference_protected(ps->sk,
+ lockdep_is_held(&ps->sk_lock)) ||
+ ps->__sk) {
+ mutex_unlock(&ps->sk_lock);
+ error = -EEXIST;
+ goto end;
+ }
+ } else {
+ cfg.pw_type = L2TP_PWTYPE_PPP;
+
+ session = l2tp_session_create(sizeof(struct pppol2tp_session),
+ tunnel, info.session_id,
+ info.peer_session_id, &cfg);
+ if (IS_ERR(session)) {
+ error = PTR_ERR(session);
+ goto end;
+ }
+
+ pppol2tp_session_init(session);
+ ps = l2tp_session_priv(session);
+ l2tp_session_inc_refcount(session);
+
+ mutex_lock(&ps->sk_lock);
+ error = l2tp_session_register(session, tunnel);
+ if (error < 0) {
+ mutex_unlock(&ps->sk_lock);
+ kfree(session);
+ goto end;
+ }
+ drop_refcnt = true;
+ new_session = true;
+ }
+
+ /* Special case: if source & dest session_id == 0x0000, this
+ * socket is being created to manage the tunnel. Just set up
+ * the internal context for use by ioctl() and sockopt()
+ * handlers.
+ */
+ if ((session->session_id == 0) &&
+ (session->peer_session_id == 0)) {
+ error = 0;
+ goto out_no_ppp;
+ }
+
+ /* The only header we need to worry about is the L2TP
+ * header. This size is different depending on whether
+ * sequence numbers are enabled for the data channel.
+ */
+ po->chan.hdrlen = PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
+
+ po->chan.private = sk;
+ po->chan.ops = &pppol2tp_chan_ops;
+ po->chan.mtu = pppol2tp_tunnel_mtu(tunnel);
+
+ error = ppp_register_net_channel(sock_net(sk), &po->chan);
+ if (error) {
+ mutex_unlock(&ps->sk_lock);
+ goto end;
+ }
+
+out_no_ppp:
+ /* This is how we get the session context from the socket. */
+ sk->sk_user_data = session;
+ rcu_assign_pointer(ps->sk, sk);
+ mutex_unlock(&ps->sk_lock);
+
+ /* Keep the reference we've grabbed on the session: sk doesn't expect
+ * the session to disappear. pppol2tp_session_destruct() is responsible
+ * for dropping it.
+ */
+ drop_refcnt = false;
+
+ sk->sk_state = PPPOX_CONNECTED;
+ l2tp_info(session, L2TP_MSG_CONTROL, "%s: created\n",
+ session->name);
+
+end:
+ if (error) {
+ if (new_session)
+ l2tp_session_delete(session);
+ if (new_tunnel)
+ l2tp_tunnel_delete(tunnel);
+ }
+ if (drop_refcnt)
+ l2tp_session_dec_refcount(session);
+ if (drop_tunnel)
+ l2tp_tunnel_dec_refcount(tunnel);
+ release_sock(sk);
+
+ return error;
+}
+
+#ifdef CONFIG_L2TP_V3
+
+/* Called when creating sessions via the netlink interface. */
+static int pppol2tp_session_create(struct net *net, struct l2tp_tunnel *tunnel,
+ u32 session_id, u32 peer_session_id,
+ struct l2tp_session_cfg *cfg)
+{
+ int error;
+ struct l2tp_session *session;
+
+ /* Error if tunnel socket is not prepped */
+ if (!tunnel->sock) {
+ error = -ENOENT;
+ goto err;
+ }
+
+ /* Allocate and initialize a new session context. */
+ session = l2tp_session_create(sizeof(struct pppol2tp_session),
+ tunnel, session_id,
+ peer_session_id, cfg);
+ if (IS_ERR(session)) {
+ error = PTR_ERR(session);
+ goto err;
+ }
+
+ pppol2tp_session_init(session);
+
+ error = l2tp_session_register(session, tunnel);
+ if (error < 0)
+ goto err_sess;
+
+ return 0;
+
+err_sess:
+ kfree(session);
+err:
+ return error;
+}
+
+#endif /* CONFIG_L2TP_V3 */
+
+/* getname() support.
+ */
+static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr,
+ int peer)
+{
+ int len = 0;
+ int error = 0;
+ struct l2tp_session *session;
+ struct l2tp_tunnel *tunnel;
+ struct sock *sk = sock->sk;
+ struct inet_sock *inet;
+ struct pppol2tp_session *pls;
+
+ error = -ENOTCONN;
+ if (sk == NULL)
+ goto end;
+ if (!(sk->sk_state & PPPOX_CONNECTED))
+ goto end;
+
+ error = -EBADF;
+ session = pppol2tp_sock_to_session(sk);
+ if (session == NULL)
+ goto end;
+
+ pls = l2tp_session_priv(session);
+ tunnel = session->tunnel;
+
+ inet = inet_sk(tunnel->sock);
+ if ((tunnel->version == 2) && (tunnel->sock->sk_family == AF_INET)) {
+ struct sockaddr_pppol2tp sp;
+ len = sizeof(sp);
+ memset(&sp, 0, len);
+ sp.sa_family = AF_PPPOX;
+ sp.sa_protocol = PX_PROTO_OL2TP;
+ sp.pppol2tp.fd = tunnel->fd;
+ sp.pppol2tp.pid = pls->owner;
+ sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
+ sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
+ sp.pppol2tp.s_session = session->session_id;
+ sp.pppol2tp.d_session = session->peer_session_id;
+ sp.pppol2tp.addr.sin_family = AF_INET;
+ sp.pppol2tp.addr.sin_port = inet->inet_dport;
+ sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
+ memcpy(uaddr, &sp, len);
+#if IS_ENABLED(CONFIG_IPV6)
+ } else if ((tunnel->version == 2) &&
+ (tunnel->sock->sk_family == AF_INET6)) {
+ struct sockaddr_pppol2tpin6 sp;
+
+ len = sizeof(sp);
+ memset(&sp, 0, len);
+ sp.sa_family = AF_PPPOX;
+ sp.sa_protocol = PX_PROTO_OL2TP;
+ sp.pppol2tp.fd = tunnel->fd;
+ sp.pppol2tp.pid = pls->owner;
+ sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
+ sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
+ sp.pppol2tp.s_session = session->session_id;
+ sp.pppol2tp.d_session = session->peer_session_id;
+ sp.pppol2tp.addr.sin6_family = AF_INET6;
+ sp.pppol2tp.addr.sin6_port = inet->inet_dport;
+ memcpy(&sp.pppol2tp.addr.sin6_addr, &tunnel->sock->sk_v6_daddr,
+ sizeof(tunnel->sock->sk_v6_daddr));
+ memcpy(uaddr, &sp, len);
+ } else if ((tunnel->version == 3) &&
+ (tunnel->sock->sk_family == AF_INET6)) {
+ struct sockaddr_pppol2tpv3in6 sp;
+
+ len = sizeof(sp);
+ memset(&sp, 0, len);
+ sp.sa_family = AF_PPPOX;
+ sp.sa_protocol = PX_PROTO_OL2TP;
+ sp.pppol2tp.fd = tunnel->fd;
+ sp.pppol2tp.pid = pls->owner;
+ sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
+ sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
+ sp.pppol2tp.s_session = session->session_id;
+ sp.pppol2tp.d_session = session->peer_session_id;
+ sp.pppol2tp.addr.sin6_family = AF_INET6;
+ sp.pppol2tp.addr.sin6_port = inet->inet_dport;
+ memcpy(&sp.pppol2tp.addr.sin6_addr, &tunnel->sock->sk_v6_daddr,
+ sizeof(tunnel->sock->sk_v6_daddr));
+ memcpy(uaddr, &sp, len);
+#endif
+ } else if (tunnel->version == 3) {
+ struct sockaddr_pppol2tpv3 sp;
+ len = sizeof(sp);
+ memset(&sp, 0, len);
+ sp.sa_family = AF_PPPOX;
+ sp.sa_protocol = PX_PROTO_OL2TP;
+ sp.pppol2tp.fd = tunnel->fd;
+ sp.pppol2tp.pid = pls->owner;
+ sp.pppol2tp.s_tunnel = tunnel->tunnel_id;
+ sp.pppol2tp.d_tunnel = tunnel->peer_tunnel_id;
+ sp.pppol2tp.s_session = session->session_id;
+ sp.pppol2tp.d_session = session->peer_session_id;
+ sp.pppol2tp.addr.sin_family = AF_INET;
+ sp.pppol2tp.addr.sin_port = inet->inet_dport;
+ sp.pppol2tp.addr.sin_addr.s_addr = inet->inet_daddr;
+ memcpy(uaddr, &sp, len);
+ }
+
+ error = len;
+
+ sock_put(sk);
+end:
+ return error;
+}
+
+/****************************************************************************
+ * ioctl() handlers.
+ *
+ * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
+ * sockets. However, in order to control kernel tunnel features, we allow
+ * userspace to create a special "tunnel" PPPoX socket which is used for
+ * control only. Tunnel PPPoX sockets have session_id == 0 and simply allow
+ * the user application to issue L2TP setsockopt(), getsockopt() and ioctl()
+ * calls.
+ ****************************************************************************/
+
+static void pppol2tp_copy_stats(struct pppol2tp_ioc_stats *dest,
+ const struct l2tp_stats *stats)
+{
+ memset(dest, 0, sizeof(*dest));
+
+ dest->tx_packets = atomic_long_read(&stats->tx_packets);
+ dest->tx_bytes = atomic_long_read(&stats->tx_bytes);
+ dest->tx_errors = atomic_long_read(&stats->tx_errors);
+ dest->rx_packets = atomic_long_read(&stats->rx_packets);
+ dest->rx_bytes = atomic_long_read(&stats->rx_bytes);
+ dest->rx_seq_discards = atomic_long_read(&stats->rx_seq_discards);
+ dest->rx_oos_packets = atomic_long_read(&stats->rx_oos_packets);
+ dest->rx_errors = atomic_long_read(&stats->rx_errors);
+}
+
+static int pppol2tp_tunnel_copy_stats(struct pppol2tp_ioc_stats *stats,
+ struct l2tp_tunnel *tunnel)
+{
+ struct l2tp_session *session;
+
+ if (!stats->session_id) {
+ pppol2tp_copy_stats(stats, &tunnel->stats);
+ return 0;
+ }
+
+ /* If session_id is set, search the corresponding session in the
+ * context of this tunnel and record the session's statistics.
+ */
+ session = l2tp_tunnel_get_session(tunnel, stats->session_id);
+ if (!session)
+ return -EBADR;
+
+ if (session->pwtype != L2TP_PWTYPE_PPP) {
+ l2tp_session_dec_refcount(session);
+ return -EBADR;
+ }
+
+ pppol2tp_copy_stats(stats, &session->stats);
+ l2tp_session_dec_refcount(session);
+
+ return 0;
+}
+
+static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd,
+ unsigned long arg)
+{
+ struct pppol2tp_ioc_stats stats;
+ struct l2tp_session *session;
+ int val;
+
+ switch (cmd) {
+ case PPPIOCGMRU:
+ case PPPIOCGFLAGS:
+ session = sock->sk->sk_user_data;
+ if (!session)
+ return -ENOTCONN;
+
+ /* Not defined for tunnels */
+ if (!session->session_id && !session->peer_session_id)
+ return -ENOSYS;
+
+ if (put_user(0, (int __user *)arg))
+ return -EFAULT;
+ break;
+
+ case PPPIOCSMRU:
+ case PPPIOCSFLAGS:
+ session = sock->sk->sk_user_data;
+ if (!session)
+ return -ENOTCONN;
+
+ /* Not defined for tunnels */
+ if (!session->session_id && !session->peer_session_id)
+ return -ENOSYS;
+
+ if (get_user(val, (int __user *)arg))
+ return -EFAULT;
+ break;
+
+ case PPPIOCGL2TPSTATS:
+ session = sock->sk->sk_user_data;
+ if (!session)
+ return -ENOTCONN;
+
+ /* Session 0 represents the parent tunnel */
+ if (!session->session_id && !session->peer_session_id) {
+ u32 session_id;
+ int err;
+
+ if (copy_from_user(&stats, (void __user *)arg,
+ sizeof(stats)))
+ return -EFAULT;
+
+ session_id = stats.session_id;
+ err = pppol2tp_tunnel_copy_stats(&stats,
+ session->tunnel);
+ if (err < 0)
+ return err;
+
+ stats.session_id = session_id;
+ } else {
+ pppol2tp_copy_stats(&stats, &session->stats);
+ stats.session_id = session->session_id;
+ }
+ stats.tunnel_id = session->tunnel->tunnel_id;
+ stats.using_ipsec = l2tp_tunnel_uses_xfrm(session->tunnel);
+
+ if (copy_to_user((void __user *)arg, &stats, sizeof(stats)))
+ return -EFAULT;
+ break;
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+
+ return 0;
+}
+
+/*****************************************************************************
+ * setsockopt() / getsockopt() support.
+ *
+ * The PPPoX socket is created for L2TP sessions: tunnels have their own UDP
+ * sockets. In order to control kernel tunnel features, we allow userspace to
+ * create a special "tunnel" PPPoX socket which is used for control only.
+ * Tunnel PPPoX sockets have session_id == 0 and simply allow the user
+ * application to issue L2TP setsockopt(), getsockopt() and ioctl() calls.
+ *****************************************************************************/
+
+/* Tunnel setsockopt() helper.
+ */
+static int pppol2tp_tunnel_setsockopt(struct sock *sk,
+ struct l2tp_tunnel *tunnel,
+ int optname, int val)
+{
+ int err = 0;
+
+ switch (optname) {
+ case PPPOL2TP_SO_DEBUG:
+ tunnel->debug = val;
+ l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: set debug=%x\n",
+ tunnel->name, tunnel->debug);
+ break;
+
+ default:
+ err = -ENOPROTOOPT;
+ break;
+ }
+
+ return err;
+}
+
+/* Session setsockopt helper.
+ */
+static int pppol2tp_session_setsockopt(struct sock *sk,
+ struct l2tp_session *session,
+ int optname, int val)
+{
+ int err = 0;
+
+ switch (optname) {
+ case PPPOL2TP_SO_RECVSEQ:
+ if ((val != 0) && (val != 1)) {
+ err = -EINVAL;
+ break;
+ }
+ session->recv_seq = !!val;
+ l2tp_info(session, L2TP_MSG_CONTROL,
+ "%s: set recv_seq=%d\n",
+ session->name, session->recv_seq);
+ break;
+
+ case PPPOL2TP_SO_SENDSEQ:
+ if ((val != 0) && (val != 1)) {
+ err = -EINVAL;
+ break;
+ }
+ session->send_seq = !!val;
+ {
+ struct pppox_sock *po = pppox_sk(sk);
+
+ po->chan.hdrlen = val ? PPPOL2TP_L2TP_HDR_SIZE_SEQ :
+ PPPOL2TP_L2TP_HDR_SIZE_NOSEQ;
+ }
+ l2tp_session_set_header_len(session, session->tunnel->version);
+ l2tp_info(session, L2TP_MSG_CONTROL,
+ "%s: set send_seq=%d\n",
+ session->name, session->send_seq);
+ break;
+
+ case PPPOL2TP_SO_LNSMODE:
+ if ((val != 0) && (val != 1)) {
+ err = -EINVAL;
+ break;
+ }
+ session->lns_mode = !!val;
+ l2tp_info(session, L2TP_MSG_CONTROL,
+ "%s: set lns_mode=%d\n",
+ session->name, session->lns_mode);
+ break;
+
+ case PPPOL2TP_SO_DEBUG:
+ session->debug = val;
+ l2tp_info(session, L2TP_MSG_CONTROL, "%s: set debug=%x\n",
+ session->name, session->debug);
+ break;
+
+ case PPPOL2TP_SO_REORDERTO:
+ session->reorder_timeout = msecs_to_jiffies(val);
+ l2tp_info(session, L2TP_MSG_CONTROL,
+ "%s: set reorder_timeout=%d\n",
+ session->name, session->reorder_timeout);
+ break;
+
+ default:
+ err = -ENOPROTOOPT;
+ break;
+ }
+
+ return err;
+}
+
+/* Main setsockopt() entry point.
+ * Does API checks, then calls either the tunnel or session setsockopt
+ * handler, according to whether the PPPoL2TP socket is a for a regular
+ * session or the special tunnel type.
+ */
+static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, unsigned int optlen)
+{
+ struct sock *sk = sock->sk;
+ struct l2tp_session *session;
+ struct l2tp_tunnel *tunnel;
+ int val;
+ int err;
+
+ if (level != SOL_PPPOL2TP)
+ return -EINVAL;
+
+ if (optlen < sizeof(int))
+ return -EINVAL;
+
+ if (get_user(val, (int __user *)optval))
+ return -EFAULT;
+
+ err = -ENOTCONN;
+ if (sk->sk_user_data == NULL)
+ goto end;
+
+ /* Get session context from the socket */
+ err = -EBADF;
+ session = pppol2tp_sock_to_session(sk);
+ if (session == NULL)
+ goto end;
+
+ /* Special case: if session_id == 0x0000, treat as operation on tunnel
+ */
+ if ((session->session_id == 0) &&
+ (session->peer_session_id == 0)) {
+ tunnel = session->tunnel;
+ err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val);
+ } else {
+ err = pppol2tp_session_setsockopt(sk, session, optname, val);
+ }
+
+ sock_put(sk);
+end:
+ return err;
+}
+
+/* Tunnel getsockopt helper. Called with sock locked.
+ */
+static int pppol2tp_tunnel_getsockopt(struct sock *sk,
+ struct l2tp_tunnel *tunnel,
+ int optname, int *val)
+{
+ int err = 0;
+
+ switch (optname) {
+ case PPPOL2TP_SO_DEBUG:
+ *val = tunnel->debug;
+ l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: get debug=%x\n",
+ tunnel->name, tunnel->debug);
+ break;
+
+ default:
+ err = -ENOPROTOOPT;
+ break;
+ }
+
+ return err;
+}
+
+/* Session getsockopt helper. Called with sock locked.
+ */
+static int pppol2tp_session_getsockopt(struct sock *sk,
+ struct l2tp_session *session,
+ int optname, int *val)
+{
+ int err = 0;
+
+ switch (optname) {
+ case PPPOL2TP_SO_RECVSEQ:
+ *val = session->recv_seq;
+ l2tp_info(session, L2TP_MSG_CONTROL,
+ "%s: get recv_seq=%d\n", session->name, *val);
+ break;
+
+ case PPPOL2TP_SO_SENDSEQ:
+ *val = session->send_seq;
+ l2tp_info(session, L2TP_MSG_CONTROL,
+ "%s: get send_seq=%d\n", session->name, *val);
+ break;
+
+ case PPPOL2TP_SO_LNSMODE:
+ *val = session->lns_mode;
+ l2tp_info(session, L2TP_MSG_CONTROL,
+ "%s: get lns_mode=%d\n", session->name, *val);
+ break;
+
+ case PPPOL2TP_SO_DEBUG:
+ *val = session->debug;
+ l2tp_info(session, L2TP_MSG_CONTROL, "%s: get debug=%d\n",
+ session->name, *val);
+ break;
+
+ case PPPOL2TP_SO_REORDERTO:
+ *val = (int) jiffies_to_msecs(session->reorder_timeout);
+ l2tp_info(session, L2TP_MSG_CONTROL,
+ "%s: get reorder_timeout=%d\n", session->name, *val);
+ break;
+
+ default:
+ err = -ENOPROTOOPT;
+ }
+
+ return err;
+}
+
+/* Main getsockopt() entry point.
+ * Does API checks, then calls either the tunnel or session getsockopt
+ * handler, according to whether the PPPoX socket is a for a regular session
+ * or the special tunnel type.
+ */
+static int pppol2tp_getsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ struct sock *sk = sock->sk;
+ struct l2tp_session *session;
+ struct l2tp_tunnel *tunnel;
+ int val, len;
+ int err;
+
+ if (level != SOL_PPPOL2TP)
+ return -EINVAL;
+
+ if (get_user(len, optlen))
+ return -EFAULT;
+
+ len = min_t(unsigned int, len, sizeof(int));
+
+ if (len < 0)
+ return -EINVAL;
+
+ err = -ENOTCONN;
+ if (sk->sk_user_data == NULL)
+ goto end;
+
+ /* Get the session context */
+ err = -EBADF;
+ session = pppol2tp_sock_to_session(sk);
+ if (session == NULL)
+ goto end;
+
+ /* Special case: if session_id == 0x0000, treat as operation on tunnel */
+ if ((session->session_id == 0) &&
+ (session->peer_session_id == 0)) {
+ tunnel = session->tunnel;
+ err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
+ if (err)
+ goto end_put_sess;
+ } else {
+ err = pppol2tp_session_getsockopt(sk, session, optname, &val);
+ if (err)
+ goto end_put_sess;
+ }
+
+ err = -EFAULT;
+ if (put_user(len, optlen))
+ goto end_put_sess;
+
+ if (copy_to_user((void __user *) optval, &val, len))
+ goto end_put_sess;
+
+ err = 0;
+
+end_put_sess:
+ sock_put(sk);
+end:
+ return err;
+}
+
+/*****************************************************************************
+ * /proc filesystem for debug
+ * Since the original pppol2tp driver provided /proc/net/pppol2tp for
+ * L2TPv2, we dump only L2TPv2 tunnels and sessions here.
+ *****************************************************************************/
+
+static unsigned int pppol2tp_net_id;
+
+#ifdef CONFIG_PROC_FS
+
+struct pppol2tp_seq_data {
+ struct seq_net_private p;
+ int tunnel_idx; /* current tunnel */
+ int session_idx; /* index of session within current tunnel */
+ struct l2tp_tunnel *tunnel;
+ struct l2tp_session *session; /* NULL means get next tunnel */
+};
+
+static void pppol2tp_next_tunnel(struct net *net, struct pppol2tp_seq_data *pd)
+{
+ /* Drop reference taken during previous invocation */
+ if (pd->tunnel)
+ l2tp_tunnel_dec_refcount(pd->tunnel);
+
+ for (;;) {
+ pd->tunnel = l2tp_tunnel_get_nth(net, pd->tunnel_idx);
+ pd->tunnel_idx++;
+
+ /* Only accept L2TPv2 tunnels */
+ if (!pd->tunnel || pd->tunnel->version == 2)
+ return;
+
+ l2tp_tunnel_dec_refcount(pd->tunnel);
+ }
+}
+
+static void pppol2tp_next_session(struct net *net, struct pppol2tp_seq_data *pd)
+{
+ /* Drop reference taken during previous invocation */
+ if (pd->session)
+ l2tp_session_dec_refcount(pd->session);
+
+ pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx);
+ pd->session_idx++;
+
+ if (pd->session == NULL) {
+ pd->session_idx = 0;
+ pppol2tp_next_tunnel(net, pd);
+ }
+}
+
+static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs)
+{
+ struct pppol2tp_seq_data *pd = SEQ_START_TOKEN;
+ loff_t pos = *offs;
+ struct net *net;
+
+ if (!pos)
+ goto out;
+
+ BUG_ON(m->private == NULL);
+ pd = m->private;
+ net = seq_file_net(m);
+
+ if (pd->tunnel == NULL)
+ pppol2tp_next_tunnel(net, pd);
+ else
+ pppol2tp_next_session(net, pd);
+
+ /* NULL tunnel and session indicates end of list */
+ if ((pd->tunnel == NULL) && (pd->session == NULL))
+ pd = NULL;
+
+out:
+ return pd;
+}
+
+static void *pppol2tp_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ (*pos)++;
+ return NULL;
+}
+
+static void pppol2tp_seq_stop(struct seq_file *p, void *v)
+{
+ struct pppol2tp_seq_data *pd = v;
+
+ if (!pd || pd == SEQ_START_TOKEN)
+ return;
+
+ /* Drop reference taken by last invocation of pppol2tp_next_session()
+ * or pppol2tp_next_tunnel().
+ */
+ if (pd->session) {
+ l2tp_session_dec_refcount(pd->session);
+ pd->session = NULL;
+ }
+ if (pd->tunnel) {
+ l2tp_tunnel_dec_refcount(pd->tunnel);
+ pd->tunnel = NULL;
+ }
+}
+
+static void pppol2tp_seq_tunnel_show(struct seq_file *m, void *v)
+{
+ struct l2tp_tunnel *tunnel = v;
+
+ seq_printf(m, "\nTUNNEL '%s', %c %d\n",
+ tunnel->name,
+ (tunnel == tunnel->sock->sk_user_data) ? 'Y' : 'N',
+ refcount_read(&tunnel->ref_count) - 1);
+ seq_printf(m, " %08x %ld/%ld/%ld %ld/%ld/%ld\n",
+ tunnel->debug,
+ atomic_long_read(&tunnel->stats.tx_packets),
+ atomic_long_read(&tunnel->stats.tx_bytes),
+ atomic_long_read(&tunnel->stats.tx_errors),
+ atomic_long_read(&tunnel->stats.rx_packets),
+ atomic_long_read(&tunnel->stats.rx_bytes),
+ atomic_long_read(&tunnel->stats.rx_errors));
+}
+
+static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
+{
+ struct l2tp_session *session = v;
+ struct l2tp_tunnel *tunnel = session->tunnel;
+ unsigned char state;
+ char user_data_ok;
+ struct sock *sk;
+ u32 ip = 0;
+ u16 port = 0;
+
+ if (tunnel->sock) {
+ struct inet_sock *inet = inet_sk(tunnel->sock);
+ ip = ntohl(inet->inet_saddr);
+ port = ntohs(inet->inet_sport);
+ }
+
+ sk = pppol2tp_session_get_sock(session);
+ if (sk) {
+ state = sk->sk_state;
+ user_data_ok = (session == sk->sk_user_data) ? 'Y' : 'N';
+ } else {
+ state = 0;
+ user_data_ok = 'N';
+ }
+
+ seq_printf(m, " SESSION '%s' %08X/%d %04X/%04X -> "
+ "%04X/%04X %d %c\n",
+ session->name, ip, port,
+ tunnel->tunnel_id,
+ session->session_id,
+ tunnel->peer_tunnel_id,
+ session->peer_session_id,
+ state, user_data_ok);
+ seq_printf(m, " 0/0/%c/%c/%s %08x %u\n",
+ session->recv_seq ? 'R' : '-',
+ session->send_seq ? 'S' : '-',
+ session->lns_mode ? "LNS" : "LAC",
+ session->debug,
+ jiffies_to_msecs(session->reorder_timeout));
+ seq_printf(m, " %hu/%hu %ld/%ld/%ld %ld/%ld/%ld\n",
+ session->nr, session->ns,
+ atomic_long_read(&session->stats.tx_packets),
+ atomic_long_read(&session->stats.tx_bytes),
+ atomic_long_read(&session->stats.tx_errors),
+ atomic_long_read(&session->stats.rx_packets),
+ atomic_long_read(&session->stats.rx_bytes),
+ atomic_long_read(&session->stats.rx_errors));
+
+ if (sk) {
+ struct pppox_sock *po = pppox_sk(sk);
+
+ seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
+ sock_put(sk);
+ }
+}
+
+static int pppol2tp_seq_show(struct seq_file *m, void *v)
+{
+ struct pppol2tp_seq_data *pd = v;
+
+ /* display header on line 1 */
+ if (v == SEQ_START_TOKEN) {
+ seq_puts(m, "PPPoL2TP driver info, " PPPOL2TP_DRV_VERSION "\n");
+ seq_puts(m, "TUNNEL name, user-data-ok session-count\n");
+ seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
+ seq_puts(m, " SESSION name, addr/port src-tid/sid "
+ "dest-tid/sid state user-data-ok\n");
+ seq_puts(m, " mtu/mru/rcvseq/sendseq/lns debug reorderto\n");
+ seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
+ goto out;
+ }
+
+ if (!pd->session)
+ pppol2tp_seq_tunnel_show(m, pd->tunnel);
+ else
+ pppol2tp_seq_session_show(m, pd->session);
+
+out:
+ return 0;
+}
+
+static const struct seq_operations pppol2tp_seq_ops = {
+ .start = pppol2tp_seq_start,
+ .next = pppol2tp_seq_next,
+ .stop = pppol2tp_seq_stop,
+ .show = pppol2tp_seq_show,
+};
+#endif /* CONFIG_PROC_FS */
+
+/*****************************************************************************
+ * Network namespace
+ *****************************************************************************/
+
+static __net_init int pppol2tp_init_net(struct net *net)
+{
+ struct proc_dir_entry *pde;
+ int err = 0;
+
+ pde = proc_create_net("pppol2tp", 0444, net->proc_net,
+ &pppol2tp_seq_ops, sizeof(struct pppol2tp_seq_data));
+ if (!pde) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+out:
+ return err;
+}
+
+static __net_exit void pppol2tp_exit_net(struct net *net)
+{
+ remove_proc_entry("pppol2tp", net->proc_net);
+}
+
+static struct pernet_operations pppol2tp_net_ops = {
+ .init = pppol2tp_init_net,
+ .exit = pppol2tp_exit_net,
+ .id = &pppol2tp_net_id,
+};
+
+/*****************************************************************************
+ * Init and cleanup
+ *****************************************************************************/
+
+static const struct proto_ops pppol2tp_ops = {
+ .family = AF_PPPOX,
+ .owner = THIS_MODULE,
+ .release = pppol2tp_release,
+ .bind = sock_no_bind,
+ .connect = pppol2tp_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = pppol2tp_getname,
+ .poll = datagram_poll,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = pppol2tp_setsockopt,
+ .getsockopt = pppol2tp_getsockopt,
+ .sendmsg = pppol2tp_sendmsg,
+ .recvmsg = pppol2tp_recvmsg,
+ .mmap = sock_no_mmap,
+ .ioctl = pppox_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = pppox_compat_ioctl,
+#endif
+};
+
+static const struct pppox_proto pppol2tp_proto = {
+ .create = pppol2tp_create,
+ .ioctl = pppol2tp_ioctl,
+ .owner = THIS_MODULE,
+};
+
+#ifdef CONFIG_L2TP_V3
+
+static const struct l2tp_nl_cmd_ops pppol2tp_nl_cmd_ops = {
+ .session_create = pppol2tp_session_create,
+ .session_delete = l2tp_session_delete,
+};
+
+#endif /* CONFIG_L2TP_V3 */
+
+static int __init pppol2tp_init(void)
+{
+ int err;
+
+ err = register_pernet_device(&pppol2tp_net_ops);
+ if (err)
+ goto out;
+
+ err = proto_register(&pppol2tp_sk_proto, 0);
+ if (err)
+ goto out_unregister_pppol2tp_pernet;
+
+ err = register_pppox_proto(PX_PROTO_OL2TP, &pppol2tp_proto);
+ if (err)
+ goto out_unregister_pppol2tp_proto;
+
+#ifdef CONFIG_L2TP_V3
+ err = l2tp_nl_register_ops(L2TP_PWTYPE_PPP, &pppol2tp_nl_cmd_ops);
+ if (err)
+ goto out_unregister_pppox;
+#endif
+
+ pr_info("PPPoL2TP kernel driver, %s\n", PPPOL2TP_DRV_VERSION);
+
+out:
+ return err;
+
+#ifdef CONFIG_L2TP_V3
+out_unregister_pppox:
+ unregister_pppox_proto(PX_PROTO_OL2TP);
+#endif
+out_unregister_pppol2tp_proto:
+ proto_unregister(&pppol2tp_sk_proto);
+out_unregister_pppol2tp_pernet:
+ unregister_pernet_device(&pppol2tp_net_ops);
+ goto out;
+}
+
+static void __exit pppol2tp_exit(void)
+{
+#ifdef CONFIG_L2TP_V3
+ l2tp_nl_unregister_ops(L2TP_PWTYPE_PPP);
+#endif
+ unregister_pppox_proto(PX_PROTO_OL2TP);
+ proto_unregister(&pppol2tp_sk_proto);
+ unregister_pernet_device(&pppol2tp_net_ops);
+}
+
+module_init(pppol2tp_init);
+module_exit(pppol2tp_exit);
+
+MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
+MODULE_DESCRIPTION("PPP over L2TP over UDP");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(PPPOL2TP_DRV_VERSION);
+MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_OL2TP);
+MODULE_ALIAS_L2TP_PWTYPE(7);