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Diffstat (limited to 'kernel/net/l2tp/l2tp_ip6.c')
-rw-r--r--kernel/net/l2tp/l2tp_ip6.c803
1 files changed, 803 insertions, 0 deletions
diff --git a/kernel/net/l2tp/l2tp_ip6.c b/kernel/net/l2tp/l2tp_ip6.c
new file mode 100644
index 000000000..d1ded3777
--- /dev/null
+++ b/kernel/net/l2tp/l2tp_ip6.c
@@ -0,0 +1,803 @@
+/*
+ * L2TPv3 IP encapsulation support for IPv6
+ *
+ * Copyright (c) 2012 Katalix Systems Ltd
+ *
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/icmp.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/random.h>
+#include <linux/socket.h>
+#include <linux/l2tp.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/udp.h>
+#include <net/inet_common.h>
+#include <net/inet_hashtables.h>
+#include <net/tcp_states.h>
+#include <net/protocol.h>
+#include <net/xfrm.h>
+
+#include <net/transp_v6.h>
+#include <net/addrconf.h>
+#include <net/ip6_route.h>
+
+#include "l2tp_core.h"
+
+struct l2tp_ip6_sock {
+ /* inet_sock has to be the first member of l2tp_ip6_sock */
+ struct inet_sock inet;
+
+ u32 conn_id;
+ u32 peer_conn_id;
+
+ /* ipv6_pinfo has to be the last member of l2tp_ip6_sock, see
+ inet6_sk_generic */
+ struct ipv6_pinfo inet6;
+};
+
+static DEFINE_RWLOCK(l2tp_ip6_lock);
+static struct hlist_head l2tp_ip6_table;
+static struct hlist_head l2tp_ip6_bind_table;
+
+static inline struct l2tp_ip6_sock *l2tp_ip6_sk(const struct sock *sk)
+{
+ return (struct l2tp_ip6_sock *)sk;
+}
+
+static struct sock *__l2tp_ip6_bind_lookup(struct net *net,
+ struct in6_addr *laddr,
+ int dif, u32 tunnel_id)
+{
+ struct sock *sk;
+
+ sk_for_each_bound(sk, &l2tp_ip6_bind_table) {
+ const struct in6_addr *addr = inet6_rcv_saddr(sk);
+ struct l2tp_ip6_sock *l2tp = l2tp_ip6_sk(sk);
+
+ if (l2tp == NULL)
+ continue;
+
+ if ((l2tp->conn_id == tunnel_id) &&
+ net_eq(sock_net(sk), net) &&
+ !(addr && ipv6_addr_equal(addr, laddr)) &&
+ !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
+ goto found;
+ }
+
+ sk = NULL;
+found:
+ return sk;
+}
+
+static inline struct sock *l2tp_ip6_bind_lookup(struct net *net,
+ struct in6_addr *laddr,
+ int dif, u32 tunnel_id)
+{
+ struct sock *sk = __l2tp_ip6_bind_lookup(net, laddr, dif, tunnel_id);
+ if (sk)
+ sock_hold(sk);
+
+ return sk;
+}
+
+/* When processing receive frames, there are two cases to
+ * consider. Data frames consist of a non-zero session-id and an
+ * optional cookie. Control frames consist of a regular L2TP header
+ * preceded by 32-bits of zeros.
+ *
+ * L2TPv3 Session Header Over IP
+ *
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Session ID |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Cookie (optional, maximum 64 bits)...
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * L2TPv3 Control Message Header Over IP
+ *
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | (32 bits of zeros) |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * |T|L|x|x|S|x|x|x|x|x|x|x| Ver | Length |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Control Connection ID |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Ns | Nr |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * All control frames are passed to userspace.
+ */
+static int l2tp_ip6_recv(struct sk_buff *skb)
+{
+ struct sock *sk;
+ u32 session_id;
+ u32 tunnel_id;
+ unsigned char *ptr, *optr;
+ struct l2tp_session *session;
+ struct l2tp_tunnel *tunnel = NULL;
+ int length;
+
+ /* Point to L2TP header */
+ optr = ptr = skb->data;
+
+ if (!pskb_may_pull(skb, 4))
+ goto discard;
+
+ session_id = ntohl(*((__be32 *) ptr));
+ ptr += 4;
+
+ /* RFC3931: L2TP/IP packets have the first 4 bytes containing
+ * the session_id. If it is 0, the packet is a L2TP control
+ * frame and the session_id value can be discarded.
+ */
+ if (session_id == 0) {
+ __skb_pull(skb, 4);
+ goto pass_up;
+ }
+
+ /* Ok, this is a data packet. Lookup the session. */
+ session = l2tp_session_find(&init_net, NULL, session_id);
+ if (session == NULL)
+ goto discard;
+
+ tunnel = session->tunnel;
+ if (tunnel == NULL)
+ goto discard;
+
+ /* Trace packet contents, if enabled */
+ if (tunnel->debug & L2TP_MSG_DATA) {
+ length = min(32u, skb->len);
+ if (!pskb_may_pull(skb, length))
+ goto discard;
+
+ pr_debug("%s: ip recv\n", tunnel->name);
+ print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, ptr, length);
+ }
+
+ l2tp_recv_common(session, skb, ptr, optr, 0, skb->len,
+ tunnel->recv_payload_hook);
+ return 0;
+
+pass_up:
+ /* Get the tunnel_id from the L2TP header */
+ if (!pskb_may_pull(skb, 12))
+ goto discard;
+
+ if ((skb->data[0] & 0xc0) != 0xc0)
+ goto discard;
+
+ tunnel_id = ntohl(*(__be32 *) &skb->data[4]);
+ tunnel = l2tp_tunnel_find(&init_net, tunnel_id);
+ if (tunnel != NULL)
+ sk = tunnel->sock;
+ else {
+ struct ipv6hdr *iph = ipv6_hdr(skb);
+
+ read_lock_bh(&l2tp_ip6_lock);
+ sk = __l2tp_ip6_bind_lookup(&init_net, &iph->daddr,
+ 0, tunnel_id);
+ read_unlock_bh(&l2tp_ip6_lock);
+ }
+
+ if (sk == NULL)
+ goto discard;
+
+ sock_hold(sk);
+
+ if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
+ goto discard_put;
+
+ nf_reset(skb);
+
+ return sk_receive_skb(sk, skb, 1);
+
+discard_put:
+ sock_put(sk);
+
+discard:
+ kfree_skb(skb);
+ return 0;
+}
+
+static int l2tp_ip6_open(struct sock *sk)
+{
+ /* Prevent autobind. We don't have ports. */
+ inet_sk(sk)->inet_num = IPPROTO_L2TP;
+
+ write_lock_bh(&l2tp_ip6_lock);
+ sk_add_node(sk, &l2tp_ip6_table);
+ write_unlock_bh(&l2tp_ip6_lock);
+
+ return 0;
+}
+
+static void l2tp_ip6_close(struct sock *sk, long timeout)
+{
+ write_lock_bh(&l2tp_ip6_lock);
+ hlist_del_init(&sk->sk_bind_node);
+ sk_del_node_init(sk);
+ write_unlock_bh(&l2tp_ip6_lock);
+
+ sk_common_release(sk);
+}
+
+static void l2tp_ip6_destroy_sock(struct sock *sk)
+{
+ struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk);
+
+ lock_sock(sk);
+ ip6_flush_pending_frames(sk);
+ release_sock(sk);
+
+ if (tunnel) {
+ l2tp_tunnel_closeall(tunnel);
+ sock_put(sk);
+ }
+
+ inet6_destroy_sock(sk);
+}
+
+static int l2tp_ip6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
+{
+ struct inet_sock *inet = inet_sk(sk);
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct sockaddr_l2tpip6 *addr = (struct sockaddr_l2tpip6 *) uaddr;
+ __be32 v4addr = 0;
+ int addr_type;
+ int err;
+
+ if (!sock_flag(sk, SOCK_ZAPPED))
+ return -EINVAL;
+ if (addr->l2tp_family != AF_INET6)
+ return -EINVAL;
+ if (addr_len < sizeof(*addr))
+ return -EINVAL;
+
+ addr_type = ipv6_addr_type(&addr->l2tp_addr);
+
+ /* l2tp_ip6 sockets are IPv6 only */
+ if (addr_type == IPV6_ADDR_MAPPED)
+ return -EADDRNOTAVAIL;
+
+ /* L2TP is point-point, not multicast */
+ if (addr_type & IPV6_ADDR_MULTICAST)
+ return -EADDRNOTAVAIL;
+
+ err = -EADDRINUSE;
+ read_lock_bh(&l2tp_ip6_lock);
+ if (__l2tp_ip6_bind_lookup(&init_net, &addr->l2tp_addr,
+ sk->sk_bound_dev_if, addr->l2tp_conn_id))
+ goto out_in_use;
+ read_unlock_bh(&l2tp_ip6_lock);
+
+ lock_sock(sk);
+
+ err = -EINVAL;
+ if (sk->sk_state != TCP_CLOSE)
+ goto out_unlock;
+
+ /* Check if the address belongs to the host. */
+ rcu_read_lock();
+ if (addr_type != IPV6_ADDR_ANY) {
+ struct net_device *dev = NULL;
+
+ if (addr_type & IPV6_ADDR_LINKLOCAL) {
+ if (addr_len >= sizeof(struct sockaddr_in6) &&
+ addr->l2tp_scope_id) {
+ /* Override any existing binding, if another
+ * one is supplied by user.
+ */
+ sk->sk_bound_dev_if = addr->l2tp_scope_id;
+ }
+
+ /* Binding to link-local address requires an
+ interface */
+ if (!sk->sk_bound_dev_if)
+ goto out_unlock_rcu;
+
+ err = -ENODEV;
+ dev = dev_get_by_index_rcu(sock_net(sk),
+ sk->sk_bound_dev_if);
+ if (!dev)
+ goto out_unlock_rcu;
+ }
+
+ /* ipv4 addr of the socket is invalid. Only the
+ * unspecified and mapped address have a v4 equivalent.
+ */
+ v4addr = LOOPBACK4_IPV6;
+ err = -EADDRNOTAVAIL;
+ if (!ipv6_chk_addr(sock_net(sk), &addr->l2tp_addr, dev, 0))
+ goto out_unlock_rcu;
+ }
+ rcu_read_unlock();
+
+ inet->inet_rcv_saddr = inet->inet_saddr = v4addr;
+ sk->sk_v6_rcv_saddr = addr->l2tp_addr;
+ np->saddr = addr->l2tp_addr;
+
+ l2tp_ip6_sk(sk)->conn_id = addr->l2tp_conn_id;
+
+ write_lock_bh(&l2tp_ip6_lock);
+ sk_add_bind_node(sk, &l2tp_ip6_bind_table);
+ sk_del_node_init(sk);
+ write_unlock_bh(&l2tp_ip6_lock);
+
+ sock_reset_flag(sk, SOCK_ZAPPED);
+ release_sock(sk);
+ return 0;
+
+out_unlock_rcu:
+ rcu_read_unlock();
+out_unlock:
+ release_sock(sk);
+ return err;
+
+out_in_use:
+ read_unlock_bh(&l2tp_ip6_lock);
+ return err;
+}
+
+static int l2tp_ip6_connect(struct sock *sk, struct sockaddr *uaddr,
+ int addr_len)
+{
+ struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *) uaddr;
+ struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
+ struct in6_addr *daddr;
+ int addr_type;
+ int rc;
+
+ if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */
+ return -EINVAL;
+
+ if (addr_len < sizeof(*lsa))
+ return -EINVAL;
+
+ if (usin->sin6_family != AF_INET6)
+ return -EINVAL;
+
+ addr_type = ipv6_addr_type(&usin->sin6_addr);
+ if (addr_type & IPV6_ADDR_MULTICAST)
+ return -EINVAL;
+
+ if (addr_type & IPV6_ADDR_MAPPED) {
+ daddr = &usin->sin6_addr;
+ if (ipv4_is_multicast(daddr->s6_addr32[3]))
+ return -EINVAL;
+ }
+
+ rc = ip6_datagram_connect(sk, uaddr, addr_len);
+
+ lock_sock(sk);
+
+ l2tp_ip6_sk(sk)->peer_conn_id = lsa->l2tp_conn_id;
+
+ write_lock_bh(&l2tp_ip6_lock);
+ hlist_del_init(&sk->sk_bind_node);
+ sk_add_bind_node(sk, &l2tp_ip6_bind_table);
+ write_unlock_bh(&l2tp_ip6_lock);
+
+ release_sock(sk);
+
+ return rc;
+}
+
+static int l2tp_ip6_disconnect(struct sock *sk, int flags)
+{
+ if (sock_flag(sk, SOCK_ZAPPED))
+ return 0;
+
+ return udp_disconnect(sk, flags);
+}
+
+static int l2tp_ip6_getname(struct socket *sock, struct sockaddr *uaddr,
+ int *uaddr_len, int peer)
+{
+ struct sockaddr_l2tpip6 *lsa = (struct sockaddr_l2tpip6 *)uaddr;
+ struct sock *sk = sock->sk;
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct l2tp_ip6_sock *lsk = l2tp_ip6_sk(sk);
+
+ lsa->l2tp_family = AF_INET6;
+ lsa->l2tp_flowinfo = 0;
+ lsa->l2tp_scope_id = 0;
+ lsa->l2tp_unused = 0;
+ if (peer) {
+ if (!lsk->peer_conn_id)
+ return -ENOTCONN;
+ lsa->l2tp_conn_id = lsk->peer_conn_id;
+ lsa->l2tp_addr = sk->sk_v6_daddr;
+ if (np->sndflow)
+ lsa->l2tp_flowinfo = np->flow_label;
+ } else {
+ if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
+ lsa->l2tp_addr = np->saddr;
+ else
+ lsa->l2tp_addr = sk->sk_v6_rcv_saddr;
+
+ lsa->l2tp_conn_id = lsk->conn_id;
+ }
+ if (ipv6_addr_type(&lsa->l2tp_addr) & IPV6_ADDR_LINKLOCAL)
+ lsa->l2tp_scope_id = sk->sk_bound_dev_if;
+ *uaddr_len = sizeof(*lsa);
+ return 0;
+}
+
+static int l2tp_ip6_backlog_recv(struct sock *sk, struct sk_buff *skb)
+{
+ int rc;
+
+ /* Charge it to the socket, dropping if the queue is full. */
+ rc = sock_queue_rcv_skb(sk, skb);
+ if (rc < 0)
+ goto drop;
+
+ return 0;
+
+drop:
+ IP_INC_STATS(&init_net, IPSTATS_MIB_INDISCARDS);
+ kfree_skb(skb);
+ return -1;
+}
+
+static int l2tp_ip6_push_pending_frames(struct sock *sk)
+{
+ struct sk_buff *skb;
+ __be32 *transhdr = NULL;
+ int err = 0;
+
+ skb = skb_peek(&sk->sk_write_queue);
+ if (skb == NULL)
+ goto out;
+
+ transhdr = (__be32 *)skb_transport_header(skb);
+ *transhdr = 0;
+
+ err = ip6_push_pending_frames(sk);
+
+out:
+ return err;
+}
+
+/* Userspace will call sendmsg() on the tunnel socket to send L2TP
+ * control frames.
+ */
+static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
+{
+ struct ipv6_txoptions opt_space;
+ DECLARE_SOCKADDR(struct sockaddr_l2tpip6 *, lsa, msg->msg_name);
+ struct in6_addr *daddr, *final_p, final;
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct ipv6_txoptions *opt = NULL;
+ struct ip6_flowlabel *flowlabel = NULL;
+ struct dst_entry *dst = NULL;
+ struct flowi6 fl6;
+ int addr_len = msg->msg_namelen;
+ int hlimit = -1;
+ int tclass = -1;
+ int dontfrag = -1;
+ int transhdrlen = 4; /* zero session-id */
+ int ulen = len + transhdrlen;
+ int err;
+
+ /* Rough check on arithmetic overflow,
+ better check is made in ip6_append_data().
+ */
+ if (len > INT_MAX)
+ return -EMSGSIZE;
+
+ /* Mirror BSD error message compatibility */
+ if (msg->msg_flags & MSG_OOB)
+ return -EOPNOTSUPP;
+
+ /*
+ * Get and verify the address.
+ */
+ memset(&fl6, 0, sizeof(fl6));
+
+ fl6.flowi6_mark = sk->sk_mark;
+
+ if (lsa) {
+ if (addr_len < SIN6_LEN_RFC2133)
+ return -EINVAL;
+
+ if (lsa->l2tp_family && lsa->l2tp_family != AF_INET6)
+ return -EAFNOSUPPORT;
+
+ daddr = &lsa->l2tp_addr;
+ if (np->sndflow) {
+ fl6.flowlabel = lsa->l2tp_flowinfo & IPV6_FLOWINFO_MASK;
+ if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
+ flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
+ if (flowlabel == NULL)
+ return -EINVAL;
+ }
+ }
+
+ /*
+ * Otherwise it will be difficult to maintain
+ * sk->sk_dst_cache.
+ */
+ if (sk->sk_state == TCP_ESTABLISHED &&
+ ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
+ daddr = &sk->sk_v6_daddr;
+
+ if (addr_len >= sizeof(struct sockaddr_in6) &&
+ lsa->l2tp_scope_id &&
+ ipv6_addr_type(daddr) & IPV6_ADDR_LINKLOCAL)
+ fl6.flowi6_oif = lsa->l2tp_scope_id;
+ } else {
+ if (sk->sk_state != TCP_ESTABLISHED)
+ return -EDESTADDRREQ;
+
+ daddr = &sk->sk_v6_daddr;
+ fl6.flowlabel = np->flow_label;
+ }
+
+ if (fl6.flowi6_oif == 0)
+ fl6.flowi6_oif = sk->sk_bound_dev_if;
+
+ if (msg->msg_controllen) {
+ opt = &opt_space;
+ memset(opt, 0, sizeof(struct ipv6_txoptions));
+ opt->tot_len = sizeof(struct ipv6_txoptions);
+
+ err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
+ &hlimit, &tclass, &dontfrag);
+ if (err < 0) {
+ fl6_sock_release(flowlabel);
+ return err;
+ }
+ if ((fl6.flowlabel & IPV6_FLOWLABEL_MASK) && !flowlabel) {
+ flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
+ if (flowlabel == NULL)
+ return -EINVAL;
+ }
+ if (!(opt->opt_nflen|opt->opt_flen))
+ opt = NULL;
+ }
+
+ if (opt == NULL)
+ opt = np->opt;
+ if (flowlabel)
+ opt = fl6_merge_options(&opt_space, flowlabel, opt);
+ opt = ipv6_fixup_options(&opt_space, opt);
+
+ fl6.flowi6_proto = sk->sk_protocol;
+ if (!ipv6_addr_any(daddr))
+ fl6.daddr = *daddr;
+ else
+ fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
+ if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
+ fl6.saddr = np->saddr;
+
+ final_p = fl6_update_dst(&fl6, opt, &final);
+
+ if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
+ fl6.flowi6_oif = np->mcast_oif;
+ else if (!fl6.flowi6_oif)
+ fl6.flowi6_oif = np->ucast_oif;
+
+ security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
+
+ dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+ if (IS_ERR(dst)) {
+ err = PTR_ERR(dst);
+ goto out;
+ }
+
+ if (hlimit < 0)
+ hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
+
+ if (tclass < 0)
+ tclass = np->tclass;
+
+ if (dontfrag < 0)
+ dontfrag = np->dontfrag;
+
+ if (msg->msg_flags & MSG_CONFIRM)
+ goto do_confirm;
+
+back_from_confirm:
+ lock_sock(sk);
+ err = ip6_append_data(sk, ip_generic_getfrag, msg,
+ ulen, transhdrlen, hlimit, tclass, opt,
+ &fl6, (struct rt6_info *)dst,
+ msg->msg_flags, dontfrag);
+ if (err)
+ ip6_flush_pending_frames(sk);
+ else if (!(msg->msg_flags & MSG_MORE))
+ err = l2tp_ip6_push_pending_frames(sk);
+ release_sock(sk);
+done:
+ dst_release(dst);
+out:
+ fl6_sock_release(flowlabel);
+
+ return err < 0 ? err : len;
+
+do_confirm:
+ dst_confirm(dst);
+ if (!(msg->msg_flags & MSG_PROBE) || len)
+ goto back_from_confirm;
+ err = 0;
+ goto done;
+}
+
+static int l2tp_ip6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
+ int noblock, int flags, int *addr_len)
+{
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ DECLARE_SOCKADDR(struct sockaddr_l2tpip6 *, lsa, msg->msg_name);
+ size_t copied = 0;
+ int err = -EOPNOTSUPP;
+ struct sk_buff *skb;
+
+ if (flags & MSG_OOB)
+ goto out;
+
+ if (addr_len)
+ *addr_len = sizeof(*lsa);
+
+ if (flags & MSG_ERRQUEUE)
+ return ipv6_recv_error(sk, msg, len, addr_len);
+
+ skb = skb_recv_datagram(sk, flags, noblock, &err);
+ if (!skb)
+ goto out;
+
+ copied = skb->len;
+ if (len < copied) {
+ msg->msg_flags |= MSG_TRUNC;
+ copied = len;
+ }
+
+ err = skb_copy_datagram_msg(skb, 0, msg, copied);
+ if (err)
+ goto done;
+
+ sock_recv_timestamp(msg, sk, skb);
+
+ /* Copy the address. */
+ if (lsa) {
+ lsa->l2tp_family = AF_INET6;
+ lsa->l2tp_unused = 0;
+ lsa->l2tp_addr = ipv6_hdr(skb)->saddr;
+ lsa->l2tp_flowinfo = 0;
+ lsa->l2tp_scope_id = 0;
+ lsa->l2tp_conn_id = 0;
+ if (ipv6_addr_type(&lsa->l2tp_addr) & IPV6_ADDR_LINKLOCAL)
+ lsa->l2tp_scope_id = inet6_iif(skb);
+ }
+
+ if (np->rxopt.all)
+ ip6_datagram_recv_ctl(sk, msg, skb);
+
+ if (flags & MSG_TRUNC)
+ copied = skb->len;
+done:
+ skb_free_datagram(sk, skb);
+out:
+ return err ? err : copied;
+}
+
+static struct proto l2tp_ip6_prot = {
+ .name = "L2TP/IPv6",
+ .owner = THIS_MODULE,
+ .init = l2tp_ip6_open,
+ .close = l2tp_ip6_close,
+ .bind = l2tp_ip6_bind,
+ .connect = l2tp_ip6_connect,
+ .disconnect = l2tp_ip6_disconnect,
+ .ioctl = udp_ioctl,
+ .destroy = l2tp_ip6_destroy_sock,
+ .setsockopt = ipv6_setsockopt,
+ .getsockopt = ipv6_getsockopt,
+ .sendmsg = l2tp_ip6_sendmsg,
+ .recvmsg = l2tp_ip6_recvmsg,
+ .backlog_rcv = l2tp_ip6_backlog_recv,
+ .hash = inet_hash,
+ .unhash = inet_unhash,
+ .obj_size = sizeof(struct l2tp_ip6_sock),
+#ifdef CONFIG_COMPAT
+ .compat_setsockopt = compat_ipv6_setsockopt,
+ .compat_getsockopt = compat_ipv6_getsockopt,
+#endif
+};
+
+static const struct proto_ops l2tp_ip6_ops = {
+ .family = PF_INET6,
+ .owner = THIS_MODULE,
+ .release = inet6_release,
+ .bind = inet6_bind,
+ .connect = inet_dgram_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = l2tp_ip6_getname,
+ .poll = datagram_poll,
+ .ioctl = inet6_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = inet_shutdown,
+ .setsockopt = sock_common_setsockopt,
+ .getsockopt = sock_common_getsockopt,
+ .sendmsg = inet_sendmsg,
+ .recvmsg = sock_common_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+#ifdef CONFIG_COMPAT
+ .compat_setsockopt = compat_sock_common_setsockopt,
+ .compat_getsockopt = compat_sock_common_getsockopt,
+#endif
+};
+
+static struct inet_protosw l2tp_ip6_protosw = {
+ .type = SOCK_DGRAM,
+ .protocol = IPPROTO_L2TP,
+ .prot = &l2tp_ip6_prot,
+ .ops = &l2tp_ip6_ops,
+};
+
+static struct inet6_protocol l2tp_ip6_protocol __read_mostly = {
+ .handler = l2tp_ip6_recv,
+};
+
+static int __init l2tp_ip6_init(void)
+{
+ int err;
+
+ pr_info("L2TP IP encapsulation support for IPv6 (L2TPv3)\n");
+
+ err = proto_register(&l2tp_ip6_prot, 1);
+ if (err != 0)
+ goto out;
+
+ err = inet6_add_protocol(&l2tp_ip6_protocol, IPPROTO_L2TP);
+ if (err)
+ goto out1;
+
+ inet6_register_protosw(&l2tp_ip6_protosw);
+ return 0;
+
+out1:
+ proto_unregister(&l2tp_ip6_prot);
+out:
+ return err;
+}
+
+static void __exit l2tp_ip6_exit(void)
+{
+ inet6_unregister_protosw(&l2tp_ip6_protosw);
+ inet6_del_protocol(&l2tp_ip6_protocol, IPPROTO_L2TP);
+ proto_unregister(&l2tp_ip6_prot);
+}
+
+module_init(l2tp_ip6_init);
+module_exit(l2tp_ip6_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Chris Elston <celston@katalix.com>");
+MODULE_DESCRIPTION("L2TP IP encapsulation for IPv6");
+MODULE_VERSION("1.0");
+
+/* Use the value of SOCK_DGRAM (2) directory, because __stringify doesn't like
+ * enums
+ */
+MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 2, IPPROTO_L2TP);