| // 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 & ~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) |
| 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) |
| 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) |
| 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; |
| 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; |
| } |
| |
| /* 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) { |
| 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) |
| goto end; |
| |
| /* Error if socket is not prepped */ |
| if (!tunnel->sock) |
| 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) |
| 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; |
| |
| /* 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 (!access_ok((int __user *)arg, sizeof(int))) |
| 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, |
| 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: |
| *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) |
| 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", |
| 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); |