diff options
Diffstat (limited to 'kernel/net/l2tp/l2tp_ppp.c')
| -rw-r--r-- | kernel/net/l2tp/l2tp_ppp.c | 1865 |
1 files changed, 1865 insertions, 0 deletions
diff --git a/kernel/net/l2tp/l2tp_ppp.c b/kernel/net/l2tp/l2tp_ppp.c new file mode 100644 index 000000000..e9b0dec56 --- /dev/null +++ b/kernel/net/l2tp/l2tp_ppp.c @@ -0,0 +1,1865 @@ +/***************************************************************************** + * Linux PPP over L2TP (PPPoX/PPPoL2TP) Sockets + * + * PPPoX --- Generic PPP encapsulation socket family + * PPPoL2TP --- PPP over L2TP (RFC 2661) + * + * Version: 2.0.0 + * + * Authors: James Chapman (jchapman@katalix.com) + * + * Based on original work by Martijn van Oosterhout <kleptog@svana.org> + * + * License: + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ + +/* This driver handles only L2TP data frames; control frames are handled by a + * userspace application. + * + * To send data in an L2TP session, userspace opens a PPPoL2TP socket and + * attaches it to a bound UDP socket with local tunnel_id / session_id and + * peer tunnel_id / session_id set. Data can then be sent or received using + * regular socket sendmsg() / recvmsg() calls. Kernel parameters of the socket + * can be read or modified using ioctl() or [gs]etsockopt() calls. + * + * When a PPPoL2TP socket is connected with local and peer session_id values + * zero, the socket is treated as a special tunnel management socket. + * + * Here's example userspace code to create a socket for sending/receiving data + * over an L2TP session:- + * + * struct sockaddr_pppol2tp sax; + * int fd; + * int session_fd; + * + * fd = socket(AF_PPPOX, SOCK_DGRAM, PX_PROTO_OL2TP); + * + * sax.sa_family = AF_PPPOX; + * sax.sa_protocol = PX_PROTO_OL2TP; + * sax.pppol2tp.fd = tunnel_fd; // bound UDP socket + * sax.pppol2tp.addr.sin_addr.s_addr = addr->sin_addr.s_addr; + * sax.pppol2tp.addr.sin_port = addr->sin_port; + * sax.pppol2tp.addr.sin_family = AF_INET; + * sax.pppol2tp.s_tunnel = tunnel_id; + * sax.pppol2tp.s_session = session_id; + * sax.pppol2tp.d_tunnel = peer_tunnel_id; + * sax.pppol2tp.d_session = peer_session_id; + * + * session_fd = connect(fd, (struct sockaddr *)&sax, sizeof(sax)); + * + * A pppd plugin that allows PPP traffic to be carried over L2TP using + * this driver is available from the OpenL2TP project at + * http://openl2tp.sourceforge.net. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/string.h> +#include <linux/list.h> +#include <linux/uaccess.h> + +#include <linux/kernel.h> +#include <linux/spinlock.h> +#include <linux/kthread.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/jiffies.h> + +#include <linux/netdevice.h> +#include <linux/net.h> +#include <linux/inetdevice.h> +#include <linux/skbuff.h> +#include <linux/init.h> +#include <linux/ip.h> +#include <linux/udp.h> +#include <linux/if_pppox.h> +#include <linux/if_pppol2tp.h> +#include <net/sock.h> +#include <linux/ppp_channel.h> +#include <linux/ppp_defs.h> +#include <linux/ppp-ioctl.h> +#include <linux/file.h> +#include <linux/hash.h> +#include <linux/sort.h> +#include <linux/proc_fs.h> +#include <linux/l2tp.h> +#include <linux/nsproxy.h> +#include <net/net_namespace.h> +#include <net/netns/generic.h> +#include <net/dst.h> +#include <net/ip.h> +#include <net/udp.h> +#include <net/xfrm.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 sock *sock; /* Pointer to the session + * PPPoX socket */ + struct sock *tunnel_sock; /* Pointer to the tunnel UDP + * socket */ + int flags; /* accessed by PPPIOCGFLAGS. + * Unused. */ +}; + +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; + +/* Helpers to obtain tunnel/session contexts from sockets. + */ +static inline struct l2tp_session *pppol2tp_sock_to_session(struct sock *sk) +{ + struct l2tp_session *session; + + if (sk == NULL) + return NULL; + + sock_hold(sk); + session = (struct l2tp_session *)(sk->sk_user_data); + if (session == NULL) { + sock_put(sk); + goto out; + } + + BUG_ON(session->magic != L2TP_SESSION_MAGIC); + +out: + return session; +} + +/***************************************************************************** + * Receive data handling + *****************************************************************************/ + +static int pppol2tp_recv_payload_hook(struct sk_buff *skb) +{ + /* Skip PPP header, if present. In testing, Microsoft L2TP clients + * don't send the PPP header (PPP header compression enabled), but + * other clients can include the header. So we cope with both cases + * here. The PPP header is always FF03 when using L2TP. + * + * Note that skb->data[] isn't dereferenced from a u16 ptr here since + * the field may be unaligned. + */ + if (!pskb_may_pull(skb, 2)) + return 1; + + if ((skb->data[0] == 0xff) && (skb->data[1] == 0x03)) + skb_pull(skb, 2); + + return 0; +} + +/* 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. + */ + sk = ps->sock; + if (sk == NULL) + goto no_sock; + + if (sk->sk_state & PPPOX_BOUND) { + struct pppox_sock *po; + l2tp_dbg(session, PPPOL2TP_MSG_DATA, + "%s: recv %d byte data frame, passing to ppp\n", + session->name, data_len); + + /* We need to forget all info related to the L2TP packet + * gathered in the skb as we are going to reuse the same + * skb for the inner packet. + * Namely we need to: + * - reset xfrm (IPSec) information as it applies to + * the outer L2TP packet and not to the inner one + * - release the dst to force a route lookup on the inner + * IP packet since skb->dst currently points to the dst + * of the UDP tunnel + * - reset netfilter information as it doesn't apply + * to the inner packet either + */ + secpath_reset(skb); + skb_dst_drop(skb); + nf_reset(skb); + + po = pppox_sk(sk); + ppp_input(&po->chan, skb); + } else { + l2tp_dbg(session, PPPOL2TP_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); + } + } + + return; + +no_sock: + l2tp_info(session, PPPOL2TP_MSG_DATA, "%s: no socket\n", session->name); + kfree_skb(skb); +} + +static void pppol2tp_session_sock_hold(struct l2tp_session *session) +{ + struct pppol2tp_session *ps = l2tp_session_priv(session); + + if (ps->sock) + sock_hold(ps->sock); +} + +static void pppol2tp_session_sock_put(struct l2tp_session *session) +{ + struct pppol2tp_session *ps = l2tp_session_priv(session); + + if (ps->sock) + sock_put(ps->sock); +} + +/************************************************************************ + * 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) +{ + static const unsigned char ppph[2] = { 0xff, 0x03 }; + struct sock *sk = sock->sk; + struct sk_buff *skb; + int error; + struct l2tp_session *session; + struct l2tp_tunnel *tunnel; + struct pppol2tp_session *ps; + int uhlen; + + error = -ENOTCONN; + if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) + goto error; + + /* Get session and tunnel contexts */ + error = -EBADF; + session = pppol2tp_sock_to_session(sk); + if (session == NULL) + goto error; + + ps = l2tp_session_priv(session); + tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock); + if (tunnel == NULL) + goto error_put_sess; + + 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 + + sizeof(ppph) + total_len, + 0, GFP_KERNEL); + if (!skb) + goto error_put_sess_tun; + + /* 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] = ppph[0]; + skb->data[1] = ppph[1]; + 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_tun; + } + + local_bh_disable(); + l2tp_xmit_skb(session, skb, session->hdr_len); + local_bh_enable(); + + sock_put(ps->tunnel_sock); + sock_put(sk); + + return total_len; + +error_put_sess_tun: + sock_put(ps->tunnel_sock); +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) +{ + static const u8 ppph[2] = { 0xff, 0x03 }; + struct sock *sk = (struct sock *) chan->private; + struct sock *sk_tun; + struct l2tp_session *session; + struct l2tp_tunnel *tunnel; + struct pppol2tp_session *ps; + int uhlen, headroom; + + if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) + goto abort; + + /* Get session and tunnel contexts from the socket */ + session = pppol2tp_sock_to_session(sk); + if (session == NULL) + goto abort; + + ps = l2tp_session_priv(session); + sk_tun = ps->tunnel_sock; + if (sk_tun == NULL) + goto abort_put_sess; + tunnel = l2tp_sock_to_tunnel(sk_tun); + if (tunnel == NULL) + goto abort_put_sess; + + 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 */ + sizeof(ppph); /* PPP header */ + if (skb_cow_head(skb, headroom)) + goto abort_put_sess_tun; + + /* Setup PPP header */ + __skb_push(skb, sizeof(ppph)); + skb->data[0] = ppph[0]; + skb->data[1] = ppph[1]; + + local_bh_disable(); + l2tp_xmit_skb(session, skb, session->hdr_len); + local_bh_enable(); + + sock_put(sk_tun); + sock_put(sk); + return 1; + +abort_put_sess_tun: + sock_put(sk_tun); +abort_put_sess: + sock_put(sk); +abort: + /* Free the original skb */ + kfree_skb(skb); + return 1; +} + +/***************************************************************************** + * Session (and tunnel control) socket create/destroy. + *****************************************************************************/ + +/* Called by l2tp_core when a session socket is being closed. + */ +static void pppol2tp_session_close(struct l2tp_session *session) +{ + struct pppol2tp_session *ps = l2tp_session_priv(session); + struct sock *sk = ps->sock; + struct socket *sock = sk->sk_socket; + + BUG_ON(session->magic != L2TP_SESSION_MAGIC); + + if (sock) { + inet_shutdown(sock, 2); + /* Don't let the session go away before our socket does */ + l2tp_session_inc_refcount(session); + } +} + +/* 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; + if (session) { + sk->sk_user_data = NULL; + BUG_ON(session->magic != L2TP_SESSION_MAGIC); + l2tp_session_dec_refcount(session); + } +} + +/* Called when the PPPoX socket (session) is closed. + */ +static int pppol2tp_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct l2tp_session *session; + int error; + + if (!sk) + return 0; + + error = -EBADF; + lock_sock(sk); + if (sock_flag(sk, SOCK_DEAD) != 0) + goto error; + + pppox_unbind_sock(sk); + + /* Signal the death of the socket. */ + sk->sk_state = PPPOX_DEAD; + sock_orphan(sk); + sock->sk = NULL; + + session = pppol2tp_sock_to_session(sk); + + /* Purge any queued data */ + if (session != NULL) { + __l2tp_session_unhash(session); + l2tp_session_queue_purge(session); + sock_put(sk); + } + skb_queue_purge(&sk->sk_receive_queue); + skb_queue_purge(&sk->sk_write_queue); + + 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 error = -ENOMEM; + struct sock *sk; + + sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppol2tp_sk_proto); + 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; +} + +#if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE) +static void pppol2tp_show(struct seq_file *m, void *arg) +{ + struct l2tp_session *session = arg; + struct pppol2tp_session *ps = l2tp_session_priv(session); + + if (ps) { + struct pppox_sock *po = pppox_sk(ps->sock); + if (po) + seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan)); + } +} +#endif + +/* 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 sockaddr_pppol2tp *sp = (struct sockaddr_pppol2tp *) uservaddr; + struct pppox_sock *po = pppox_sk(sk); + struct l2tp_session *session = NULL; + struct l2tp_tunnel *tunnel; + struct pppol2tp_session *ps; + struct dst_entry *dst; + struct l2tp_session_cfg cfg = { 0, }; + int error = 0; + u32 tunnel_id, peer_tunnel_id; + u32 session_id, peer_session_id; + int ver = 2; + int fd; + + lock_sock(sk); + + error = -EINVAL; + if (sp->sa_protocol != PX_PROTO_OL2TP) + goto end; + + /* 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 */ + + /* Get params from socket address. Handle L2TPv2 and L2TPv3. + * This is nasty because there are different sockaddr_pppol2tp + * structs for L2TPv2, L2TPv3, over IPv4 and IPv6. We use + * the sockaddr size to determine which structure the caller + * is using. + */ + peer_tunnel_id = 0; + if (sockaddr_len == sizeof(struct sockaddr_pppol2tp)) { + fd = sp->pppol2tp.fd; + tunnel_id = sp->pppol2tp.s_tunnel; + peer_tunnel_id = sp->pppol2tp.d_tunnel; + session_id = sp->pppol2tp.s_session; + peer_session_id = sp->pppol2tp.d_session; + } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpv3)) { + struct sockaddr_pppol2tpv3 *sp3 = + (struct sockaddr_pppol2tpv3 *) sp; + ver = 3; + fd = sp3->pppol2tp.fd; + tunnel_id = sp3->pppol2tp.s_tunnel; + peer_tunnel_id = sp3->pppol2tp.d_tunnel; + session_id = sp3->pppol2tp.s_session; + peer_session_id = sp3->pppol2tp.d_session; + } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpin6)) { + struct sockaddr_pppol2tpin6 *sp6 = + (struct sockaddr_pppol2tpin6 *) sp; + fd = sp6->pppol2tp.fd; + tunnel_id = sp6->pppol2tp.s_tunnel; + peer_tunnel_id = sp6->pppol2tp.d_tunnel; + session_id = sp6->pppol2tp.s_session; + peer_session_id = sp6->pppol2tp.d_session; + } else if (sockaddr_len == sizeof(struct sockaddr_pppol2tpv3in6)) { + struct sockaddr_pppol2tpv3in6 *sp6 = + (struct sockaddr_pppol2tpv3in6 *) sp; + ver = 3; + fd = sp6->pppol2tp.fd; + tunnel_id = sp6->pppol2tp.s_tunnel; + peer_tunnel_id = sp6->pppol2tp.d_tunnel; + session_id = sp6->pppol2tp.s_session; + peer_session_id = sp6->pppol2tp.d_session; + } else { + error = -EINVAL; + goto end; /* bad socket address */ + } + + /* Don't bind if tunnel_id is 0 */ + error = -EINVAL; + if (tunnel_id == 0) + goto end; + + tunnel = l2tp_tunnel_find(sock_net(sk), 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 ((session_id == 0) && (peer_session_id == 0)) { + if (tunnel == NULL) { + struct l2tp_tunnel_cfg tcfg = { + .encap = L2TP_ENCAPTYPE_UDP, + .debug = 0, + }; + error = l2tp_tunnel_create(sock_net(sk), fd, ver, tunnel_id, peer_tunnel_id, &tcfg, &tunnel); + if (error < 0) + goto end; + } + } else { + /* Error if we can't find the tunnel */ + error = -ENOENT; + if (tunnel == NULL) + goto end; + + /* Error if socket is not prepped */ + if (tunnel->sock == NULL) + goto end; + } + + if (tunnel->recv_payload_hook == NULL) + tunnel->recv_payload_hook = pppol2tp_recv_payload_hook; + + if (tunnel->peer_tunnel_id == 0) + tunnel->peer_tunnel_id = peer_tunnel_id; + + /* Create session if it doesn't already exist. We handle the + * case where a session was previously created by the netlink + * interface by checking that the session doesn't already have + * a socket and its tunnel socket are what we expect. If any + * of those checks fail, return EEXIST to the caller. + */ + session = l2tp_session_find(sock_net(sk), tunnel, session_id); + if (session == NULL) { + /* Default MTU must allow space for UDP/L2TP/PPP + * headers. + */ + cfg.mtu = cfg.mru = 1500 - PPPOL2TP_HEADER_OVERHEAD; + + /* Allocate and initialize a new session context. */ + session = l2tp_session_create(sizeof(struct pppol2tp_session), + tunnel, session_id, + peer_session_id, &cfg); + if (session == NULL) { + error = -ENOMEM; + goto end; + } + } else { + ps = l2tp_session_priv(session); + error = -EEXIST; + if (ps->sock != NULL) + goto end; + + /* consistency checks */ + if (ps->tunnel_sock != tunnel->sock) + goto end; + } + + /* Associate session with its PPPoL2TP socket */ + ps = l2tp_session_priv(session); + ps->owner = current->pid; + ps->sock = sk; + ps->tunnel_sock = tunnel->sock; + + session->recv_skb = pppol2tp_recv; + session->session_close = pppol2tp_session_close; +#if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE) + session->show = pppol2tp_show; +#endif + + /* We need to know each time a skb is dropped from the reorder + * queue. + */ + session->ref = pppol2tp_session_sock_hold; + session->deref = pppol2tp_session_sock_put; + + /* If PMTU discovery was enabled, use the MTU that was discovered */ + dst = sk_dst_get(tunnel->sock); + if (dst != NULL) { + u32 pmtu = dst_mtu(dst); + + if (pmtu != 0) + session->mtu = session->mru = pmtu - + PPPOL2TP_HEADER_OVERHEAD; + dst_release(dst); + } + + /* 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 = session->mtu; + + error = ppp_register_net_channel(sock_net(sk), &po->chan); + if (error) + goto end; + +out_no_ppp: + /* This is how we get the session context from the socket. */ + sk->sk_user_data = session; + sk->sk_state = PPPOX_CONNECTED; + l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: created\n", + session->name); + +end: + 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, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg) +{ + int error; + struct l2tp_tunnel *tunnel; + struct l2tp_session *session; + struct pppol2tp_session *ps; + + tunnel = l2tp_tunnel_find(net, tunnel_id); + + /* Error if we can't find the tunnel */ + error = -ENOENT; + if (tunnel == NULL) + goto out; + + /* Error if tunnel socket is not prepped */ + if (tunnel->sock == NULL) + goto out; + + /* Check that this session doesn't already exist */ + error = -EEXIST; + session = l2tp_session_find(net, tunnel, session_id); + if (session != NULL) + goto out; + + /* Default MTU values. */ + if (cfg->mtu == 0) + cfg->mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD; + if (cfg->mru == 0) + cfg->mru = cfg->mtu; + + /* Allocate and initialize a new session context. */ + error = -ENOMEM; + session = l2tp_session_create(sizeof(struct pppol2tp_session), + tunnel, session_id, + peer_session_id, cfg); + if (session == NULL) + goto out; + + ps = l2tp_session_priv(session); + ps->tunnel_sock = tunnel->sock; + + l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: created\n", + session->name); + + error = 0; + +out: + return error; +} + +#endif /* CONFIG_L2TP_V3 */ + +/* getname() support. + */ +static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr, + int *usockaddr_len, int peer) +{ + int len = 0; + int error = 0; + struct l2tp_session *session; + struct l2tp_tunnel *tunnel; + struct sock *sk = sock->sk; + struct inet_sock *inet; + struct pppol2tp_session *pls; + + error = -ENOTCONN; + if (sk == NULL) + goto end; + if (sk->sk_state != PPPOX_CONNECTED) + goto end; + + error = -EBADF; + session = pppol2tp_sock_to_session(sk); + if (session == NULL) + goto end; + + pls = l2tp_session_priv(session); + tunnel = l2tp_sock_to_tunnel(pls->tunnel_sock); + if (tunnel == NULL) { + error = -EBADF; + goto end_put_sess; + } + + 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); + } + + *usockaddr_len = len; + + sock_put(pls->tunnel_sock); +end_put_sess: + sock_put(sk); + error = 0; + +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, + struct l2tp_stats *stats) +{ + 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); +} + +/* Session ioctl helper. + */ +static int pppol2tp_session_ioctl(struct l2tp_session *session, + unsigned int cmd, unsigned long arg) +{ + struct ifreq ifr; + int err = 0; + struct sock *sk; + int val = (int) arg; + struct pppol2tp_session *ps = l2tp_session_priv(session); + struct l2tp_tunnel *tunnel = session->tunnel; + struct pppol2tp_ioc_stats stats; + + l2tp_dbg(session, PPPOL2TP_MSG_CONTROL, + "%s: pppol2tp_session_ioctl(cmd=%#x, arg=%#lx)\n", + session->name, cmd, arg); + + sk = ps->sock; + sock_hold(sk); + + switch (cmd) { + case SIOCGIFMTU: + err = -ENXIO; + if (!(sk->sk_state & PPPOX_CONNECTED)) + break; + + err = -EFAULT; + if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq))) + break; + ifr.ifr_mtu = session->mtu; + if (copy_to_user((void __user *) arg, &ifr, sizeof(struct ifreq))) + break; + + l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get mtu=%d\n", + session->name, session->mtu); + err = 0; + break; + + case SIOCSIFMTU: + err = -ENXIO; + if (!(sk->sk_state & PPPOX_CONNECTED)) + break; + + err = -EFAULT; + if (copy_from_user(&ifr, (void __user *) arg, sizeof(struct ifreq))) + break; + + session->mtu = ifr.ifr_mtu; + + l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set mtu=%d\n", + session->name, session->mtu); + err = 0; + break; + + case PPPIOCGMRU: + err = -ENXIO; + if (!(sk->sk_state & PPPOX_CONNECTED)) + break; + + err = -EFAULT; + if (put_user(session->mru, (int __user *) arg)) + break; + + l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get mru=%d\n", + session->name, session->mru); + err = 0; + break; + + case PPPIOCSMRU: + err = -ENXIO; + if (!(sk->sk_state & PPPOX_CONNECTED)) + break; + + err = -EFAULT; + if (get_user(val, (int __user *) arg)) + break; + + session->mru = val; + l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set mru=%d\n", + session->name, session->mru); + err = 0; + break; + + case PPPIOCGFLAGS: + err = -EFAULT; + if (put_user(ps->flags, (int __user *) arg)) + break; + + l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get flags=%d\n", + session->name, ps->flags); + err = 0; + break; + + case PPPIOCSFLAGS: + err = -EFAULT; + if (get_user(val, (int __user *) arg)) + break; + ps->flags = val; + l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: set flags=%d\n", + session->name, ps->flags); + err = 0; + break; + + case PPPIOCGL2TPSTATS: + err = -ENXIO; + if (!(sk->sk_state & PPPOX_CONNECTED)) + break; + + memset(&stats, 0, sizeof(stats)); + stats.tunnel_id = tunnel->tunnel_id; + stats.session_id = session->session_id; + pppol2tp_copy_stats(&stats, &session->stats); + if (copy_to_user((void __user *) arg, &stats, + sizeof(stats))) + break; + l2tp_info(session, PPPOL2TP_MSG_CONTROL, "%s: get L2TP stats\n", + session->name); + err = 0; + break; + + default: + err = -ENOSYS; + break; + } + + sock_put(sk); + + return err; +} + +/* Tunnel ioctl helper. + * + * Note the special handling for PPPIOCGL2TPSTATS below. If the ioctl data + * specifies a session_id, the session ioctl handler is called. This allows an + * application to retrieve session stats via a tunnel socket. + */ +static int pppol2tp_tunnel_ioctl(struct l2tp_tunnel *tunnel, + unsigned int cmd, unsigned long arg) +{ + int err = 0; + struct sock *sk; + struct pppol2tp_ioc_stats stats; + + l2tp_dbg(tunnel, PPPOL2TP_MSG_CONTROL, + "%s: pppol2tp_tunnel_ioctl(cmd=%#x, arg=%#lx)\n", + tunnel->name, cmd, arg); + + sk = tunnel->sock; + sock_hold(sk); + + switch (cmd) { + case PPPIOCGL2TPSTATS: + err = -ENXIO; + if (!(sk->sk_state & PPPOX_CONNECTED)) + break; + + if (copy_from_user(&stats, (void __user *) arg, + sizeof(stats))) { + err = -EFAULT; + break; + } + if (stats.session_id != 0) { + /* resend to session ioctl handler */ + struct l2tp_session *session = + l2tp_session_find(sock_net(sk), tunnel, stats.session_id); + if (session != NULL) + err = pppol2tp_session_ioctl(session, cmd, arg); + else + err = -EBADR; + break; + } +#ifdef CONFIG_XFRM + stats.using_ipsec = (sk->sk_policy[0] || sk->sk_policy[1]) ? 1 : 0; +#endif + pppol2tp_copy_stats(&stats, &tunnel->stats); + if (copy_to_user((void __user *) arg, &stats, sizeof(stats))) { + err = -EFAULT; + break; + } + l2tp_info(tunnel, PPPOL2TP_MSG_CONTROL, "%s: get L2TP stats\n", + tunnel->name); + err = 0; + break; + + default: + err = -ENOSYS; + break; + } + + sock_put(sk); + + return err; +} + +/* Main ioctl() handler. + * Dispatch to tunnel or session helpers depending on the socket. + */ +static int pppol2tp_ioctl(struct socket *sock, unsigned int cmd, + unsigned long arg) +{ + struct sock *sk = sock->sk; + struct l2tp_session *session; + struct l2tp_tunnel *tunnel; + struct pppol2tp_session *ps; + int err; + + if (!sk) + return 0; + + err = -EBADF; + if (sock_flag(sk, SOCK_DEAD) != 0) + goto end; + + err = -ENOTCONN; + if ((sk->sk_user_data == NULL) || + (!(sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)))) + goto end; + + /* Get session context from the socket */ + err = -EBADF; + session = pppol2tp_sock_to_session(sk); + if (session == NULL) + goto end; + + /* Special case: if session's session_id is zero, treat ioctl as a + * tunnel ioctl + */ + ps = l2tp_session_priv(session); + if ((session->session_id == 0) && + (session->peer_session_id == 0)) { + err = -EBADF; + tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock); + if (tunnel == NULL) + goto end_put_sess; + + err = pppol2tp_tunnel_ioctl(tunnel, cmd, arg); + sock_put(ps->tunnel_sock); + goto end_put_sess; + } + + err = pppol2tp_session_ioctl(session, cmd, arg); + +end_put_sess: + sock_put(sk); +end: + return err; +} + +/***************************************************************************** + * 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, PPPOL2TP_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; + struct pppol2tp_session *ps = l2tp_session_priv(session); + + switch (optname) { + case PPPOL2TP_SO_RECVSEQ: + if ((val != 0) && (val != 1)) { + err = -EINVAL; + break; + } + session->recv_seq = val ? -1 : 0; + l2tp_info(session, PPPOL2TP_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 ? -1 : 0; + { + struct sock *ssk = ps->sock; + struct pppox_sock *po = pppox_sk(ssk); + 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, PPPOL2TP_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 ? -1 : 0; + l2tp_info(session, PPPOL2TP_MSG_CONTROL, + "%s: set lns_mode=%d\n", + session->name, session->lns_mode); + break; + + case PPPOL2TP_SO_DEBUG: + session->debug = val; + l2tp_info(session, PPPOL2TP_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, PPPOL2TP_MSG_CONTROL, + "%s: set reorder_timeout=%d\n", + session->name, session->reorder_timeout); + break; + + default: + err = -ENOPROTOOPT; + break; + } + + return err; +} + +/* Main setsockopt() entry point. + * Does API checks, then calls either the tunnel or session setsockopt + * handler, according to whether the PPPoL2TP socket is a for a regular + * session or the special tunnel type. + */ +static int pppol2tp_setsockopt(struct socket *sock, int level, int optname, + char __user *optval, unsigned int optlen) +{ + struct sock *sk = sock->sk; + struct l2tp_session *session; + struct l2tp_tunnel *tunnel; + struct pppol2tp_session *ps; + int val; + int err; + + if (level != SOL_PPPOL2TP) + return -EINVAL; + + if (optlen < sizeof(int)) + return -EINVAL; + + if (get_user(val, (int __user *)optval)) + return -EFAULT; + + err = -ENOTCONN; + if (sk->sk_user_data == NULL) + goto end; + + /* Get session context from the socket */ + err = -EBADF; + session = pppol2tp_sock_to_session(sk); + if (session == NULL) + goto end; + + /* Special case: if session_id == 0x0000, treat as operation on tunnel + */ + ps = l2tp_session_priv(session); + if ((session->session_id == 0) && + (session->peer_session_id == 0)) { + err = -EBADF; + tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock); + if (tunnel == NULL) + goto end_put_sess; + + err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val); + sock_put(ps->tunnel_sock); + } else + err = pppol2tp_session_setsockopt(sk, session, optname, val); + + err = 0; + +end_put_sess: + 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, PPPOL2TP_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, PPPOL2TP_MSG_CONTROL, + "%s: get recv_seq=%d\n", session->name, *val); + break; + + case PPPOL2TP_SO_SENDSEQ: + *val = session->send_seq; + l2tp_info(session, PPPOL2TP_MSG_CONTROL, + "%s: get send_seq=%d\n", session->name, *val); + break; + + case PPPOL2TP_SO_LNSMODE: + *val = session->lns_mode; + l2tp_info(session, PPPOL2TP_MSG_CONTROL, + "%s: get lns_mode=%d\n", session->name, *val); + break; + + case PPPOL2TP_SO_DEBUG: + *val = session->debug; + l2tp_info(session, PPPOL2TP_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, PPPOL2TP_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; + struct pppol2tp_session *ps; + + if (level != SOL_PPPOL2TP) + return -EINVAL; + + if (get_user(len, optlen)) + return -EFAULT; + + len = min_t(unsigned int, len, sizeof(int)); + + if (len < 0) + return -EINVAL; + + err = -ENOTCONN; + if (sk->sk_user_data == NULL) + goto end; + + /* Get the session context */ + err = -EBADF; + session = pppol2tp_sock_to_session(sk); + if (session == NULL) + goto end; + + /* Special case: if session_id == 0x0000, treat as operation on tunnel */ + ps = l2tp_session_priv(session); + if ((session->session_id == 0) && + (session->peer_session_id == 0)) { + err = -EBADF; + tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock); + if (tunnel == NULL) + goto end_put_sess; + + err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val); + sock_put(ps->tunnel_sock); + } else + err = pppol2tp_session_getsockopt(sk, session, optname, &val); + + 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) +{ + for (;;) { + pd->tunnel = l2tp_tunnel_find_nth(net, pd->tunnel_idx); + pd->tunnel_idx++; + + if (pd->tunnel == NULL) + break; + + /* Ignore L2TPv3 tunnels */ + if (pd->tunnel->version < 3) + break; + } +} + +static void pppol2tp_next_session(struct net *net, struct pppol2tp_seq_data *pd) +{ + pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx); + pd->session_idx++; + + if (pd->session == NULL) { + pd->session_idx = 0; + pppol2tp_next_tunnel(net, pd); + } +} + +static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs) +{ + struct pppol2tp_seq_data *pd = SEQ_START_TOKEN; + loff_t pos = *offs; + struct net *net; + + if (!pos) + goto out; + + BUG_ON(m->private == NULL); + pd = m->private; + net = seq_file_net(m); + + if (pd->tunnel == NULL) + pppol2tp_next_tunnel(net, pd); + else + pppol2tp_next_session(net, pd); + + /* NULL tunnel and session indicates end of list */ + if ((pd->tunnel == NULL) && (pd->session == NULL)) + pd = NULL; + +out: + return pd; +} + +static void *pppol2tp_seq_next(struct seq_file *m, void *v, loff_t *pos) +{ + (*pos)++; + return NULL; +} + +static void pppol2tp_seq_stop(struct seq_file *p, void *v) +{ + /* nothing to do */ +} + +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', + atomic_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; + struct pppol2tp_session *ps = l2tp_session_priv(session); + struct pppox_sock *po = pppox_sk(ps->sock); + 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); + } + + 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, + ps->sock->sk_state, + (session == ps->sock->sk_user_data) ? + 'Y' : 'N'); + seq_printf(m, " %d/%d/%c/%c/%s %08x %u\n", + session->mtu, session->mru, + 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 (po) + seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan)); +} + +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; + } + + /* Show the tunnel or session context. + */ + if (pd->session == NULL) + 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, +}; + +/* Called when our /proc file is opened. We allocate data for use when + * iterating our tunnel / session contexts and store it in the private + * data of the seq_file. + */ +static int pppol2tp_proc_open(struct inode *inode, struct file *file) +{ + return seq_open_net(inode, file, &pppol2tp_seq_ops, + sizeof(struct pppol2tp_seq_data)); +} + +static const struct file_operations pppol2tp_proc_fops = { + .owner = THIS_MODULE, + .open = pppol2tp_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release_net, +}; + +#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("pppol2tp", S_IRUGO, net->proc_net, + &pppol2tp_proc_fops); + 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, +}; + +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("pppox-proto-" __stringify(PX_PROTO_OL2TP)); |