net/l2tp/l2tp_ppp.c

20  * To send data in an L2TP session, userspace opens a PPPoL2TP socket and
30  * over an L2TP session:-
113 /* Private data of each session. This data lives at the end of struct
114  * l2tp_session, referenced via session->priv[].
120 	struct sock __rcu	*sk;		/* Pointer to the session PPPoX socket */
133 /* Retrieves the pppol2tp socket associated to a session.
137 static struct sock *pppol2tp_session_get_sock(struct l2tp_session *session)
139 	struct pppol2tp_session *ps = l2tp_session_priv(session);
151 /* Helpers to obtain tunnel/session contexts from sockets.
155 	struct l2tp_session *session;
161 	session = (struct l2tp_session *)(sk->sk_user_data);
162 	if (!session) {
166 	if (WARN_ON(session->magic != L2TP_SESSION_MAGIC)) {
167 		session = NULL;
173 	return session;
212 static void pppol2tp_recv(struct l2tp_session *session, struct sk_buff *skb, int data_len)
214 	struct pppol2tp_session *ps = l2tp_session_priv(session);
218 	 * queue it on the session socket.
243 			atomic_long_inc(&session->stats.rx_errors);
253 	pr_warn_ratelimited("%s: no socket in recv\n", session->name);
262  * when a user application does a sendmsg() on the session socket. L2TP and
271 	struct l2tp_session *session;
279 	/* Get session and tunnel contexts */
281 	session = pppol2tp_sock_to_session(sk);
282 	if (!session)
285 	tunnel = session->tunnel;
292 			   uhlen + session->hdr_len +
318 	l2tp_xmit_skb(session, skb);
348 	struct l2tp_session *session;
355 	/* Get session and tunnel contexts from the socket */
356 	session = pppol2tp_sock_to_session(sk);
357 	if (!session)
360 	tunnel = session->tunnel;
366 		   session->hdr_len +	/* L2TP header */
377 	l2tp_xmit_skb(session, skb);
404 /* Really kill the session socket. (Called from sock_put() if
409 	struct l2tp_session *session = sk->sk_user_data;
414 	if (session) {
416 		if (WARN_ON(session->magic != L2TP_SESSION_MAGIC))
418 		l2tp_session_dec_refcount(session);
422 /* Called when the PPPoX socket (session) is closed.
427 	struct l2tp_session *session;
445 	session = pppol2tp_sock_to_session(sk);
446 	if (session) {
449 		l2tp_session_delete(session);
451 		ps = l2tp_session_priv(session);
467 	/* This will delete the session context via
528 	struct l2tp_session *session = arg;
531 	sk = pppol2tp_session_get_sock(session);
540 static void pppol2tp_session_init(struct l2tp_session *session)
544 	session->recv_skb = pppol2tp_recv;
546 		session->show = pppol2tp_show;
548 	ps = l2tp_session_priv(session);
719 	struct l2tp_session *session = NULL;
756 	session = l2tp_tunnel_get_session(tunnel, info.session_id);
757 	if (session) {
760 		if (session->pwtype != L2TP_PWTYPE_PPP) {
765 		ps = l2tp_session_priv(session);
767 		/* Using a pre-existing session is fine as long as it hasn't
781 		session = l2tp_session_create(sizeof(struct pppol2tp_session),
784 		if (IS_ERR(session)) {
785 			error = PTR_ERR(session);
789 		pppol2tp_session_init(session);
790 		ps = l2tp_session_priv(session);
791 		l2tp_session_inc_refcount(session);
794 		error = l2tp_session_register(session, tunnel);
797 			kfree(session);
809 	if (session->session_id == 0 && session->peer_session_id == 0) {
831 	/* This is how we get the session context from the socket. */
832 	sk->sk_user_data = session;
836 	/* Keep the reference we've grabbed on the session: sk doesn't expect
837 	 * the session to disappear. pppol2tp_session_destruct() is responsible
847 			l2tp_session_delete(session);
852 		l2tp_session_dec_refcount(session);
867 	struct l2tp_session *session;
875 	/* Allocate and initialize a new session context. */
876 	session = l2tp_session_create(sizeof(struct pppol2tp_session),
879 	if (IS_ERR(session)) {
880 		error = PTR_ERR(session);
884 	pppol2tp_session_init(session);
886 	error = l2tp_session_register(session, tunnel);
893 	kfree(session);
907 	struct l2tp_session *session;
920 	session = pppol2tp_sock_to_session(sk);
921 	if (!session)
924 	pls = l2tp_session_priv(session);
925 	tunnel = session->tunnel;
939 		sp.pppol2tp.s_session = session->session_id;
940 		sp.pppol2tp.d_session = session->peer_session_id;
957 		sp.pppol2tp.s_session = session->session_id;
958 		sp.pppol2tp.d_session = session->peer_session_id;
975 		sp.pppol2tp.s_session = session->session_id;
976 		sp.pppol2tp.d_session = session->peer_session_id;
994 		sp.pppol2tp.s_session = session->session_id;
995 		sp.pppol2tp.d_session = session->peer_session_id;
1038 	struct l2tp_session *session;
1045 	/* If session_id is set, search the corresponding session in the
1046 	 * context of this tunnel and record the session's statistics.
1048 	session = l2tp_tunnel_get_session(tunnel, stats->session_id);
1049 	if (!session)
1052 	if (session->pwtype != L2TP_PWTYPE_PPP) {
1053 		l2tp_session_dec_refcount(session);
1057 	pppol2tp_copy_stats(stats, &session->stats);
1058 	l2tp_session_dec_refcount(session);
1067 	struct l2tp_session *session;
1072 		session = sock->sk->sk_user_data;
1073 		if (!session)
1076 		if (WARN_ON(session->magic != L2TP_SESSION_MAGIC))
1080 		if (!session->session_id && !session->peer_session_id)
1089 		session = sock->sk->sk_user_data;
1090 		if (!session)
1093 		if (WARN_ON(session->magic != L2TP_SESSION_MAGIC))
1097 		if (!session->session_id && !session->peer_session_id)
1105 		session = sock->sk->sk_user_data;
1106 		if (!session)
1109 		if (WARN_ON(session->magic != L2TP_SESSION_MAGIC))
1113 		if (!session->session_id && !session->peer_session_id) {
1123 							 session->tunnel);
1129 			pppol2tp_copy_stats(&stats, &session->stats);
1130 			stats.session_id = session->session_id;
1132 		stats.tunnel_id = session->tunnel->tunnel_id;
1133 		stats.using_ipsec = l2tp_tunnel_uses_xfrm(session->tunnel);
1180 				       struct l2tp_session *session,
1191 		session->recv_seq = !!val;
1199 		session->send_seq = !!val;
1206 		l2tp_session_set_header_len(session, session->tunnel->version);
1214 		session->lns_mode = !!val;
1222 		session->reorder_timeout = msecs_to_jiffies(val);
1234  * Does API checks, then calls either the tunnel or session setsockopt
1236  * session or the special tunnel type.
1242 	struct l2tp_session *session;
1260 	/* Get session context from the socket */
1262 	session = pppol2tp_sock_to_session(sk);
1263 	if (!session)
1268 	if (session->session_id == 0 && session->peer_session_id == 0) {
1269 		tunnel = session->tunnel;
1272 		err = pppol2tp_session_setsockopt(sk, session, optname, val);
1305 				       struct l2tp_session *session,
1312 		*val = session->recv_seq;
1316 		*val = session->send_seq;
1320 		*val = session->lns_mode;
1329 		*val = (int)jiffies_to_msecs(session->reorder_timeout);
1340  * Does API checks, then calls either the tunnel or session getsockopt
1341  * handler, according to whether the PPPoX socket is a for a regular session
1348 	struct l2tp_session *session;
1368 	/* Get the session context */
1370 	session = pppol2tp_sock_to_session(sk);
1371 	if (!session)
1375 	if (session->session_id == 0 && session->peer_session_id == 0) {
1376 		tunnel = session->tunnel;
1381 		err = pppol2tp_session_getsockopt(sk, session, optname, &val);
1414 	int session_idx;		/* index of session within current tunnel */
1416 	struct l2tp_session *session;	/* NULL means get next tunnel */
1440 	if (pd->session)
1441 		l2tp_session_dec_refcount(pd->session);
1443 	pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx);
1446 	if (!pd->session) {
1474 	/* NULL tunnel and session indicates end of list */
1475 	if (!pd->tunnel && !pd->session)
1498 	if (pd->session) {
1499 		l2tp_session_dec_refcount(pd->session);
1500 		pd->session = NULL;
1528 	struct l2tp_session *session = v;
1529 	struct l2tp_tunnel *tunnel = session->tunnel;
1543 	sk = pppol2tp_session_get_sock(session);
1546 		user_data_ok = (session == sk->sk_user_data) ? 'Y' : 'N';
1553 		   session->name, ip, port,
1555 		   session->session_id,
1557 		   session->peer_session_id,
1560 		   session->recv_seq ? 'R' : '-',
1561 		   session->send_seq ? 'S' : '-',
1562 		   session->lns_mode ? "LNS" : "LAC",
1564 		   jiffies_to_msecs(session->reorder_timeout));
1566 		   session->nr, session->ns,
1567 		   atomic_long_read(&session->stats.tx_packets),
1568 		   atomic_long_read(&session->stats.tx_bytes),
1569 		   atomic_long_read(&session->stats.tx_errors),
1570 		   atomic_long_read(&session->stats.rx_packets),
1571 		   atomic_long_read(&session->stats.rx_bytes),
1572 		   atomic_long_read(&session->stats.rx_errors));
1589 		seq_puts(m, "TUNNEL name, user-data-ok session-count\n");
1597 	if (!pd->session)
1600 		pppol2tp_seq_session_show(m, pd->session);