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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /net/l2tp/l2tp_ppp.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/l2tp/l2tp_ppp.c')
-rw-r--r-- | net/l2tp/l2tp_ppp.c | 1743 |
1 files changed, 1743 insertions, 0 deletions
diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c new file mode 100644 index 0000000000..f011af6601 --- /dev/null +++ b/net/l2tp/l2tp_ppp.c @@ -0,0 +1,1743 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/***************************************************************************** + * 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 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) + return NULL; + + sock_hold(sk); + session = (struct l2tp_session *)(sk->sk_user_data); + if (!session) { + sock_put(sk); + goto out; + } + if (WARN_ON(session->magic != L2TP_SESSION_MAGIC)) { + session = NULL; + sock_put(sk); + goto out; + } + +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, &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) + 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 negotiated 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; + + po = pppox_sk(sk); + ppp_input(&po->chan, skb); + } else { + 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(); + pr_warn_ratelimited("%s: no socket in recv\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) + 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); + 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) + 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); + 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; + if (WARN_ON(session->magic != L2TP_SESSION_MAGIC)) + return; + 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; +} + +static struct l2tp_tunnel *pppol2tp_tunnel_get(struct net *net, + const struct l2tp_connect_info *info, + bool *new_tunnel) +{ + struct l2tp_tunnel *tunnel; + int error; + + *new_tunnel = false; + + tunnel = l2tp_tunnel_get(net, info->tunnel_id); + + /* 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) { + struct l2tp_tunnel_cfg tcfg = { + .encap = L2TP_ENCAPTYPE_UDP, + }; + + /* Prevent l2tp_tunnel_register() from trying to set up + * a kernel socket. + */ + if (info->fd < 0) + return ERR_PTR(-EBADF); + + error = l2tp_tunnel_create(info->fd, + info->version, + info->tunnel_id, + info->peer_tunnel_id, &tcfg, + &tunnel); + if (error < 0) + return ERR_PTR(error); + + l2tp_tunnel_inc_refcount(tunnel); + error = l2tp_tunnel_register(tunnel, net, &tcfg); + if (error < 0) { + kfree(tunnel); + return ERR_PTR(error); + } + + *new_tunnel = true; + } + } else { + /* Error if we can't find the tunnel */ + if (!tunnel) + return ERR_PTR(-ENOENT); + + /* Error if socket is not prepped */ + if (!tunnel->sock) { + l2tp_tunnel_dec_refcount(tunnel); + return ERR_PTR(-ENOENT); + } + } + + return tunnel; +} + +/* 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 new_session = false; + bool new_tunnel = false; + int error; + + error = pppol2tp_sockaddr_get_info(uservaddr, sockaddr_len, &info); + if (error < 0) + return error; + + /* Don't bind if tunnel_id is 0 */ + if (!info.tunnel_id) + return -EINVAL; + + tunnel = pppol2tp_tunnel_get(sock_net(sk), &info, &new_tunnel); + if (IS_ERR(tunnel)) + return PTR_ERR(tunnel); + + 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 */ + + 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; + +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); + 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) + goto end; + if (!(sk->sk_state & PPPOX_CONNECTED)) + goto end; + + error = -EBADF; + session = pppol2tp_sock_to_session(sk); + if (!session) + 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; + + switch (cmd) { + case PPPIOCGMRU: + case PPPIOCGFLAGS: + session = sock->sk->sk_user_data; + if (!session) + return -ENOTCONN; + + if (WARN_ON(session->magic != L2TP_SESSION_MAGIC)) + return -EBADF; + + /* 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; + + if (WARN_ON(session->magic != L2TP_SESSION_MAGIC)) + return -EBADF; + + /* Not defined for tunnels */ + if (!session->session_id && !session->peer_session_id) + return -ENOSYS; + + if (!access_ok((int __user *)arg, sizeof(int))) + return -EFAULT; + break; + + case PPPIOCGL2TPSTATS: + session = sock->sk->sk_user_data; + if (!session) + return -ENOTCONN; + + if (WARN_ON(session->magic != L2TP_SESSION_MAGIC)) + return -EBADF; + + /* 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 flags option is deprecated */ + 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; + 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); + break; + + case PPPOL2TP_SO_LNSMODE: + if (val != 0 && val != 1) { + err = -EINVAL; + break; + } + session->lns_mode = !!val; + break; + + case PPPOL2TP_SO_DEBUG: + /* Session debug flags option is deprecated */ + break; + + case PPPOL2TP_SO_REORDERTO: + session->reorder_timeout = msecs_to_jiffies(val); + 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, + sockptr_t 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 (copy_from_sockptr(&val, optval, sizeof(int))) + return -EFAULT; + + err = -ENOTCONN; + if (!sk->sk_user_data) + goto end; + + /* Get session context from the socket */ + err = -EBADF; + session = pppol2tp_sock_to_session(sk); + if (!session) + 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: + /* Tunnel debug flags option is deprecated */ + *val = 0; + 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; + break; + + case PPPOL2TP_SO_SENDSEQ: + *val = session->send_seq; + break; + + case PPPOL2TP_SO_LNSMODE: + *val = session->lns_mode; + break; + + case PPPOL2TP_SO_DEBUG: + /* Session debug flags option is deprecated */ + *val = 0; + break; + + case PPPOL2TP_SO_REORDERTO: + *val = (int)jiffies_to_msecs(session->reorder_timeout); + 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) + goto end; + + /* Get the session context */ + err = -EBADF; + session = pppol2tp_sock_to_session(sk); + if (!session) + 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) { + 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; + + if (WARN_ON(!m->private)) { + pd = NULL; + goto out; + } + + pd = m->private; + net = seq_file_net(m); + + if (!pd->tunnel) + pppol2tp_next_tunnel(net, pd); + else + pppol2tp_next_session(net, pd); + + /* NULL tunnel and session indicates end of list */ + if (!pd->tunnel && !pd->session) + 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", + 0, + 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", + 0, + jiffies_to_msecs(session->reorder_timeout)); + seq_printf(m, " %u/%u %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); |