/***************************************************************************** * 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 * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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 */ 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 int pppol2tp_get_channel_protocol(struct ppp_channel *); static int pppol2tp_get_channel_protocol_ver(struct ppp_channel *); static void pppol2tp_hold_chan(struct ppp_channel *); static void pppol2tp_release_chan(struct ppp_channel *); static const struct pppol2tp_channel_ops pppol2tp_chan_ops = { .ops.start_xmit = pppol2tp_xmit, .ops.get_channel_protocol = pppol2tp_get_channel_protocol, .ops.get_channel_protocol_ver = pppol2tp_get_channel_protocol_ver, .ops.hold = pppol2tp_hold_chan, .ops.release = pppol2tp_release_chan, }; 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 == 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] == PPP_ALLSTATIONS) && (skb->data[1] == PPP_UI)) 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. */ rcu_read_lock(); sk = rcu_dereference(ps->sk); if (sk == NULL) goto no_sock; 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); /* 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); skb->skb_iif = ppp_dev_index(&po->chan); 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; 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 + 2 + total_len, /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */ 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] = 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_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; } /* pppol2tp_hold_chan() */ static void pppol2tp_hold_chan(struct ppp_channel *chan) { struct sock *sk = (struct sock *)chan->private; sock_hold(sk); } /* pppol2tp_release_chan() */ static void pppol2tp_release_chan(struct ppp_channel *chan) { struct sock *sk = (struct sock *)chan->private; sock_put(sk); } /* pppol2tp_get_channel_protocol() * Return the protocol type of the L2TP over PPP protocol */ static int pppol2tp_get_channel_protocol(struct ppp_channel *chan) { return PX_PROTO_OL2TP; } /* pppol2tp_get_channel_protocol_ver() * Return the protocol version of the L2TP over PPP protocol */ static int pppol2tp_get_channel_protocol_ver(struct ppp_channel *chan) { struct sock *sk; struct l2tp_session *session; struct l2tp_tunnel *tunnel; struct pppol2tp_session *ps; int version = 0; if (chan && chan->private) sk = (struct sock *)chan->private; else return -1; /* Get session and tunnel contexts from the socket */ session = pppol2tp_sock_to_session(sk); if (!session) return -1; ps = l2tp_session_priv(session); if (!ps->tunnel_sock) { sock_put(sk); return -1; } tunnel = l2tp_sock_to_tunnel(ps->tunnel_sock); if (!tunnel) { sock_put(sk); return -1; } version = tunnel->version; sock_put(ps->tunnel_sock); sock_put(sk); return version; } /* pppol2tp_get_addressing() */ static int pppol2tp_get_addressing(struct ppp_channel *chan, struct pppol2tp_common_addr *addr) { struct sock *sk = (struct sock *)chan->private; struct sock *sk_tun; struct l2tp_session *session; struct l2tp_tunnel *tunnel; struct pppol2tp_session *ps; struct inet_sock *isk = NULL; int err = -ENXIO; /* Get session and tunnel contexts from the socket */ session = pppol2tp_sock_to_session(sk); if (!session) return err; ps = l2tp_session_priv(session); sk_tun = ps->tunnel_sock; if (!sk_tun) { sock_put(sk); return err; } tunnel = l2tp_sock_to_tunnel(sk_tun); if (!tunnel) { sock_put(sk_tun); sock_put(sk); return err; } isk = inet_sk(ps->tunnel_sock); addr->local_tunnel_id = tunnel->tunnel_id; addr->remote_tunnel_id = tunnel->peer_tunnel_id; addr->local_session_id = session->session_id; addr->remote_session_id = session->peer_session_id; addr->local_addr.sin_port = isk->inet_sport; addr->remote_addr.sin_port = isk->inet_dport; addr->local_addr.sin_addr.s_addr = isk->inet_saddr; addr->remote_addr.sin_addr.s_addr = isk->inet_daddr; sock_put(sk_tun); sock_put(sk); return 0; } /* pppol2tp_channel_addressing_get() */ int pppol2tp_channel_addressing_get(struct ppp_channel *chan, struct pppol2tp_common_addr *addr) { return pppol2tp_get_addressing(chan, addr); } EXPORT_SYMBOL(pppol2tp_channel_addressing_get); /* 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 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 */ 2; /* 2 bytes for PPP_ALLSTATIONS & PPP_UI */ if (skb_cow_head(skb, headroom)) goto abort_put_sess_tun; /* Setup PPP header */ __skb_push(skb, 2); skb->data[0] = PPP_ALLSTATIONS; skb->data[1] = PPP_UI; /* set incoming interface as the ppp interface */ if ((skb->protocol == htons(ETH_P_IP)) || (skb->protocol == htons(ETH_P_IPV6))) skb->skb_iif = ppp_dev_index(chan); 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 sock *sk; BUG_ON(session->magic != L2TP_SESSION_MAGIC); sk = pppol2tp_session_get_sock(session); if (sk) { if (sk->sk_socket) inet_shutdown(sk->sk_socket, SEND_SHUTDOWN); sock_put(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; BUG_ON(session->magic != L2TP_SESSION_MAGIC); l2tp_session_dec_refcount(session); } } static void pppol2tp_put_sk(struct rcu_head *head) { struct pppol2tp_session *ps; ps = container_of(head, typeof(*ps), rcu); sock_put(ps->__sk); } /* 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 != NULL) { 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; } #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 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); } } #endif static void pppol2tp_session_init(struct l2tp_session *session) { struct pppol2tp_session *ps; struct dst_entry *dst; 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 ps = l2tp_session_priv(session); mutex_init(&ps->sk_lock); ps->tunnel_sock = session->tunnel->sock; ps->owner = current->pid; /* If PMTU discovery was enabled, use the MTU that was discovered */ dst = sk_dst_get(session->tunnel->sock); if (dst) { u32 pmtu = dst_mtu(dst); if (pmtu) { session->mtu = pmtu - PPPOL2TP_HEADER_OVERHEAD; session->mru = pmtu - PPPOL2TP_HEADER_OVERHEAD; } dst_release(dst); } } /* 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 l2tp_session_cfg cfg = { 0, }; int error = 0; u32 tunnel_id, peer_tunnel_id; u32 session_id, peer_session_id; bool drop_refcnt = false; int ver = 2; int fd; lock_sock(sk); error = -EINVAL; if (sockaddr_len != sizeof(struct sockaddr_pppol2tp) && sockaddr_len != sizeof(struct sockaddr_pppol2tpv3) && sockaddr_len != sizeof(struct sockaddr_pppol2tpin6) && sockaddr_len != sizeof(struct sockaddr_pppol2tpv3in6)) goto end; 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; session = l2tp_session_get(sock_net(sk), tunnel, session_id, false); if (session) { drop_refcnt = true; 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))) { mutex_unlock(&ps->sk_lock); error = -EEXIST; goto end; } /* consistency checks */ if (ps->tunnel_sock != tunnel->sock) { mutex_unlock(&ps->sk_lock); error = -EEXIST; goto end; } } else { /* Default MTU must allow space for UDP/L2TP/PPP headers */ cfg.mtu = 1500 - PPPOL2TP_HEADER_OVERHEAD; cfg.mru = cfg.mtu; session = l2tp_session_create(sizeof(struct pppol2tp_session), tunnel, session_id, 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; } /* 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.ops; po->chan.mtu = session->mtu; 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 (drop_refcnt) l2tp_session_dec_refcount(session); 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; } /* 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. */ 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 *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) 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; error = 0; sock_put(pls->tunnel_sock); end_put_sess: 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, 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, L2TP_MSG_CONTROL, "%s: pppol2tp_session_ioctl(cmd=%#x, arg=%#lx)\n", session->name, cmd, arg); sk = pppol2tp_session_get_sock(session); if (!sk) return -EBADR; 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, L2TP_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, L2TP_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, L2TP_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, L2TP_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, L2TP_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, L2TP_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, L2TP_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, L2TP_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_get(sock_net(sk), tunnel, stats.session_id, true); if (session) { err = pppol2tp_session_ioctl(session, cmd, arg); if (session->deref) session->deref(session); l2tp_session_dec_refcount(session); } 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, L2TP_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, 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 ? -1 : 0; 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 ? -1 : 0; { 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 ? -1 : 0; 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, 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, 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; 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_get_nth(pd->tunnel, pd->session_idx, true); 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; 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, " %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 (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; } /* Show the tunnel or session context. */ if (!pd->session) { pppol2tp_seq_tunnel_show(m, pd->tunnel); } else { pppol2tp_seq_session_show(m, pd->session); if (pd->session->deref) pd->session->deref(pd->session); l2tp_session_dec_refcount(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, #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 "); MODULE_DESCRIPTION("PPP over L2TP over UDP"); MODULE_LICENSE("GPL"); MODULE_VERSION(PPPOL2TP_DRV_VERSION); MODULE_ALIAS("pppox-proto-" __stringify(PX_PROTO_OL2TP)); MODULE_ALIAS_L2TP_PWTYPE(7);