diff options
Diffstat (limited to 'net/l2tp/pppol2tp.c')
-rw-r--r-- | net/l2tp/pppol2tp.c | 2680 |
1 files changed, 0 insertions, 2680 deletions
diff --git a/net/l2tp/pppol2tp.c b/net/l2tp/pppol2tp.c deleted file mode 100644 index 449a9825200d..000000000000 --- a/net/l2tp/pppol2tp.c +++ /dev/null @@ -1,2680 +0,0 @@ -/***************************************************************************** - * Linux PPP over L2TP (PPPoX/PPPoL2TP) Sockets - * - * PPPoX --- Generic PPP encapsulation socket family - * PPPoL2TP --- PPP over L2TP (RFC 2661) - * - * Version: 1.0.0 - * - * Authors: Martijn van Oosterhout <kleptog@svana.org> - * James Chapman (jchapman@katalix.com) - * Contributors: - * Michal Ostrowski <mostrows@speakeasy.net> - * Arnaldo Carvalho de Melo <acme@xconectiva.com.br> - * David S. Miller (davem@redhat.com) - * - * 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. - */ - -#include <linux/module.h> -#include <linux/string.h> -#include <linux/list.h> -#include <asm/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/if_ppp.h> -#include <linux/file.h> -#include <linux/hash.h> -#include <linux/sort.h> -#include <linux/proc_fs.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 <asm/byteorder.h> -#include <asm/atomic.h> - - -#define PPPOL2TP_DRV_VERSION "V1.0" - -/* L2TP header constants */ -#define L2TP_HDRFLAG_T 0x8000 -#define L2TP_HDRFLAG_L 0x4000 -#define L2TP_HDRFLAG_S 0x0800 -#define L2TP_HDRFLAG_O 0x0200 -#define L2TP_HDRFLAG_P 0x0100 - -#define L2TP_HDR_VER_MASK 0x000F -#define L2TP_HDR_VER 0x0002 - -/* Space for UDP, L2TP and PPP headers */ -#define PPPOL2TP_HEADER_OVERHEAD 40 - -/* Just some random numbers */ -#define L2TP_TUNNEL_MAGIC 0x42114DDA -#define L2TP_SESSION_MAGIC 0x0C04EB7D - -#define PPPOL2TP_HASH_BITS 4 -#define PPPOL2TP_HASH_SIZE (1 << PPPOL2TP_HASH_BITS) - -/* Default trace flags */ -#define PPPOL2TP_DEFAULT_DEBUG_FLAGS 0 - -#define PRINTK(_mask, _type, _lvl, _fmt, args...) \ - do { \ - if ((_mask) & (_type)) \ - printk(_lvl "PPPOL2TP: " _fmt, ##args); \ - } while(0) - -/* 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 - -struct pppol2tp_tunnel; - -/* Describes a session. It is the sk_user_data field in the PPPoL2TP - * socket. Contains information to determine incoming packets and transmit - * outgoing ones. - */ -struct pppol2tp_session -{ - int magic; /* should be - * L2TP_SESSION_MAGIC */ - 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 */ - - struct pppol2tp_addr tunnel_addr; /* Description of tunnel */ - - struct pppol2tp_tunnel *tunnel; /* back pointer to tunnel - * context */ - - char name[20]; /* "sess xxxxx/yyyyy", where - * x=tunnel_id, y=session_id */ - int mtu; - int mru; - int flags; /* accessed by PPPIOCGFLAGS. - * Unused. */ - unsigned recv_seq:1; /* expect receive packets with - * sequence numbers? */ - unsigned send_seq:1; /* send packets with sequence - * numbers? */ - unsigned lns_mode:1; /* behave as LNS? LAC enables - * sequence numbers under - * control of LNS. */ - int debug; /* bitmask of debug message - * categories */ - int reorder_timeout; /* configured reorder timeout - * (in jiffies) */ - u16 nr; /* session NR state (receive) */ - u16 ns; /* session NR state (send) */ - struct sk_buff_head reorder_q; /* receive reorder queue */ - struct pppol2tp_ioc_stats stats; - struct hlist_node hlist; /* Hash list node */ -}; - -/* The sk_user_data field of the tunnel's UDP socket. It contains info to track - * all the associated sessions so incoming packets can be sorted out - */ -struct pppol2tp_tunnel -{ - int magic; /* Should be L2TP_TUNNEL_MAGIC */ - rwlock_t hlist_lock; /* protect session_hlist */ - struct hlist_head session_hlist[PPPOL2TP_HASH_SIZE]; - /* hashed list of sessions, - * hashed by id */ - int debug; /* bitmask of debug message - * categories */ - char name[12]; /* "tunl xxxxx" */ - struct pppol2tp_ioc_stats stats; - - void (*old_sk_destruct)(struct sock *); - - struct sock *sock; /* Parent socket */ - struct list_head list; /* Keep a list of all open - * prepared sockets */ - struct net *pppol2tp_net; /* the net we belong to */ - - atomic_t ref_count; -}; - -/* Private data stored for received packets in the skb. - */ -struct pppol2tp_skb_cb { - u16 ns; - u16 nr; - u16 has_seq; - u16 length; - unsigned long expires; -}; - -#define PPPOL2TP_SKB_CB(skb) ((struct pppol2tp_skb_cb *) &skb->cb[sizeof(struct inet_skb_parm)]) - -static int pppol2tp_xmit(struct ppp_channel *chan, struct sk_buff *skb); -static void pppol2tp_tunnel_free(struct pppol2tp_tunnel *tunnel); - -static atomic_t pppol2tp_tunnel_count; -static atomic_t pppol2tp_session_count; -static struct ppp_channel_ops pppol2tp_chan_ops = { pppol2tp_xmit , NULL }; -static const struct proto_ops pppol2tp_ops; - -/* per-net private data for this module */ -static int pppol2tp_net_id __read_mostly; -struct pppol2tp_net { - struct list_head pppol2tp_tunnel_list; - rwlock_t pppol2tp_tunnel_list_lock; -}; - -static inline struct pppol2tp_net *pppol2tp_pernet(struct net *net) -{ - BUG_ON(!net); - - return net_generic(net, pppol2tp_net_id); -} - -/* Helpers to obtain tunnel/session contexts from sockets. - */ -static inline struct pppol2tp_session *pppol2tp_sock_to_session(struct sock *sk) -{ - struct pppol2tp_session *session; - - if (sk == NULL) - return NULL; - - sock_hold(sk); - session = (struct pppol2tp_session *)(sk->sk_user_data); - if (session == NULL) { - sock_put(sk); - goto out; - } - - BUG_ON(session->magic != L2TP_SESSION_MAGIC); -out: - return session; -} - -static inline struct pppol2tp_tunnel *pppol2tp_sock_to_tunnel(struct sock *sk) -{ - struct pppol2tp_tunnel *tunnel; - - if (sk == NULL) - return NULL; - - sock_hold(sk); - tunnel = (struct pppol2tp_tunnel *)(sk->sk_user_data); - if (tunnel == NULL) { - sock_put(sk); - goto out; - } - - BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); -out: - return tunnel; -} - -/* Tunnel reference counts. Incremented per session that is added to - * the tunnel. - */ -static inline void pppol2tp_tunnel_inc_refcount(struct pppol2tp_tunnel *tunnel) -{ - atomic_inc(&tunnel->ref_count); -} - -static inline void pppol2tp_tunnel_dec_refcount(struct pppol2tp_tunnel *tunnel) -{ - if (atomic_dec_and_test(&tunnel->ref_count)) - pppol2tp_tunnel_free(tunnel); -} - -/* Session hash list. - * The session_id SHOULD be random according to RFC2661, but several - * L2TP implementations (Cisco and Microsoft) use incrementing - * session_ids. So we do a real hash on the session_id, rather than a - * simple bitmask. - */ -static inline struct hlist_head * -pppol2tp_session_id_hash(struct pppol2tp_tunnel *tunnel, u16 session_id) -{ - unsigned long hash_val = (unsigned long) session_id; - return &tunnel->session_hlist[hash_long(hash_val, PPPOL2TP_HASH_BITS)]; -} - -/* Lookup a session by id - */ -static struct pppol2tp_session * -pppol2tp_session_find(struct pppol2tp_tunnel *tunnel, u16 session_id) -{ - struct hlist_head *session_list = - pppol2tp_session_id_hash(tunnel, session_id); - struct pppol2tp_session *session; - struct hlist_node *walk; - - read_lock_bh(&tunnel->hlist_lock); - hlist_for_each_entry(session, walk, session_list, hlist) { - if (session->tunnel_addr.s_session == session_id) { - read_unlock_bh(&tunnel->hlist_lock); - return session; - } - } - read_unlock_bh(&tunnel->hlist_lock); - - return NULL; -} - -/* Lookup a tunnel by id - */ -static struct pppol2tp_tunnel *pppol2tp_tunnel_find(struct net *net, u16 tunnel_id) -{ - struct pppol2tp_tunnel *tunnel; - struct pppol2tp_net *pn = pppol2tp_pernet(net); - - read_lock_bh(&pn->pppol2tp_tunnel_list_lock); - list_for_each_entry(tunnel, &pn->pppol2tp_tunnel_list, list) { - if (tunnel->stats.tunnel_id == tunnel_id) { - read_unlock_bh(&pn->pppol2tp_tunnel_list_lock); - return tunnel; - } - } - read_unlock_bh(&pn->pppol2tp_tunnel_list_lock); - - return NULL; -} - -/***************************************************************************** - * Receive data handling - *****************************************************************************/ - -/* Queue a skb in order. We come here only if the skb has an L2TP sequence - * number. - */ -static void pppol2tp_recv_queue_skb(struct pppol2tp_session *session, struct sk_buff *skb) -{ - struct sk_buff *skbp; - struct sk_buff *tmp; - u16 ns = PPPOL2TP_SKB_CB(skb)->ns; - - spin_lock_bh(&session->reorder_q.lock); - skb_queue_walk_safe(&session->reorder_q, skbp, tmp) { - if (PPPOL2TP_SKB_CB(skbp)->ns > ns) { - __skb_queue_before(&session->reorder_q, skbp, skb); - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG, - "%s: pkt %hu, inserted before %hu, reorder_q len=%d\n", - session->name, ns, PPPOL2TP_SKB_CB(skbp)->ns, - skb_queue_len(&session->reorder_q)); - session->stats.rx_oos_packets++; - goto out; - } - } - - __skb_queue_tail(&session->reorder_q, skb); - -out: - spin_unlock_bh(&session->reorder_q.lock); -} - -/* Dequeue a single skb. - */ -static void pppol2tp_recv_dequeue_skb(struct pppol2tp_session *session, struct sk_buff *skb) -{ - struct pppol2tp_tunnel *tunnel = session->tunnel; - int length = PPPOL2TP_SKB_CB(skb)->length; - struct sock *session_sock = NULL; - - /* We're about to requeue the skb, so return resources - * to its current owner (a socket receive buffer). - */ - skb_orphan(skb); - - tunnel->stats.rx_packets++; - tunnel->stats.rx_bytes += length; - session->stats.rx_packets++; - session->stats.rx_bytes += length; - - if (PPPOL2TP_SKB_CB(skb)->has_seq) { - /* Bump our Nr */ - session->nr++; - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG, - "%s: updated nr to %hu\n", session->name, session->nr); - } - - /* If the socket is bound, send it in to PPP's input queue. Otherwise - * queue it on the session socket. - */ - session_sock = session->sock; - if (session_sock->sk_state & PPPOX_BOUND) { - struct pppox_sock *po; - PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG, - "%s: recv %d byte data frame, passing to ppp\n", - session->name, length); - - /* 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(session_sock); - ppp_input(&po->chan, skb); - } else { - PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_INFO, - "%s: socket not bound\n", session->name); - - /* Not bound. Nothing we can do, so discard. */ - session->stats.rx_errors++; - kfree_skb(skb); - } - - sock_put(session->sock); -} - -/* Dequeue skbs from the session's reorder_q, subject to packet order. - * Skbs that have been in the queue for too long are simply discarded. - */ -static void pppol2tp_recv_dequeue(struct pppol2tp_session *session) -{ - struct sk_buff *skb; - struct sk_buff *tmp; - - /* If the pkt at the head of the queue has the nr that we - * expect to send up next, dequeue it and any other - * in-sequence packets behind it. - */ - spin_lock_bh(&session->reorder_q.lock); - skb_queue_walk_safe(&session->reorder_q, skb, tmp) { - if (time_after(jiffies, PPPOL2TP_SKB_CB(skb)->expires)) { - session->stats.rx_seq_discards++; - session->stats.rx_errors++; - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG, - "%s: oos pkt %hu len %d discarded (too old), " - "waiting for %hu, reorder_q_len=%d\n", - session->name, PPPOL2TP_SKB_CB(skb)->ns, - PPPOL2TP_SKB_CB(skb)->length, session->nr, - skb_queue_len(&session->reorder_q)); - __skb_unlink(skb, &session->reorder_q); - kfree_skb(skb); - sock_put(session->sock); - continue; - } - - if (PPPOL2TP_SKB_CB(skb)->has_seq) { - if (PPPOL2TP_SKB_CB(skb)->ns != session->nr) { - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG, - "%s: holding oos pkt %hu len %d, " - "waiting for %hu, reorder_q_len=%d\n", - session->name, PPPOL2TP_SKB_CB(skb)->ns, - PPPOL2TP_SKB_CB(skb)->length, session->nr, - skb_queue_len(&session->reorder_q)); - goto out; - } - } - __skb_unlink(skb, &session->reorder_q); - - /* Process the skb. We release the queue lock while we - * do so to let other contexts process the queue. - */ - spin_unlock_bh(&session->reorder_q.lock); - pppol2tp_recv_dequeue_skb(session, skb); - spin_lock_bh(&session->reorder_q.lock); - } - -out: - spin_unlock_bh(&session->reorder_q.lock); -} - -static inline int pppol2tp_verify_udp_checksum(struct sock *sk, - struct sk_buff *skb) -{ - struct udphdr *uh = udp_hdr(skb); - u16 ulen = ntohs(uh->len); - struct inet_sock *inet; - __wsum psum; - - if (sk->sk_no_check || skb_csum_unnecessary(skb) || !uh->check) - return 0; - - inet = inet_sk(sk); - psum = csum_tcpudp_nofold(inet->inet_saddr, inet->inet_daddr, ulen, - IPPROTO_UDP, 0); - - if ((skb->ip_summed == CHECKSUM_COMPLETE) && - !csum_fold(csum_add(psum, skb->csum))) - return 0; - - skb->csum = psum; - - return __skb_checksum_complete(skb); -} - -/* Internal receive frame. Do the real work of receiving an L2TP data frame - * here. The skb is not on a list when we get here. - * Returns 0 if the packet was a data packet and was successfully passed on. - * Returns 1 if the packet was not a good data packet and could not be - * forwarded. All such packets are passed up to userspace to deal with. - */ -static int pppol2tp_recv_core(struct sock *sock, struct sk_buff *skb) -{ - struct pppol2tp_session *session = NULL; - struct pppol2tp_tunnel *tunnel; - unsigned char *ptr, *optr; - u16 hdrflags; - u16 tunnel_id, session_id; - int length; - int offset; - - tunnel = pppol2tp_sock_to_tunnel(sock); - if (tunnel == NULL) - goto no_tunnel; - - if (tunnel->sock && pppol2tp_verify_udp_checksum(tunnel->sock, skb)) - goto discard_bad_csum; - - /* UDP always verifies the packet length. */ - __skb_pull(skb, sizeof(struct udphdr)); - - /* Short packet? */ - if (!pskb_may_pull(skb, 12)) { - PRINTK(tunnel->debug, PPPOL2TP_MSG_DATA, KERN_INFO, - "%s: recv short packet (len=%d)\n", tunnel->name, skb->len); - goto error; - } - - /* Point to L2TP header */ - optr = ptr = skb->data; - - /* Get L2TP header flags */ - hdrflags = ntohs(*(__be16*)ptr); - - /* Trace packet contents, if enabled */ - if (tunnel->debug & PPPOL2TP_MSG_DATA) { - length = min(16u, skb->len); - if (!pskb_may_pull(skb, length)) - goto error; - - printk(KERN_DEBUG "%s: recv: ", tunnel->name); - - offset = 0; - do { - printk(" %02X", ptr[offset]); - } while (++offset < length); - - printk("\n"); - } - - /* Get length of L2TP packet */ - length = skb->len; - - /* If type is control packet, it is handled by userspace. */ - if (hdrflags & L2TP_HDRFLAG_T) { - PRINTK(tunnel->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG, - "%s: recv control packet, len=%d\n", tunnel->name, length); - goto error; - } - - /* Skip flags */ - ptr += 2; - - /* If length is present, skip it */ - if (hdrflags & L2TP_HDRFLAG_L) - ptr += 2; - - /* Extract tunnel and session ID */ - tunnel_id = ntohs(*(__be16 *) ptr); - ptr += 2; - session_id = ntohs(*(__be16 *) ptr); - ptr += 2; - - /* Find the session context */ - session = pppol2tp_session_find(tunnel, session_id); - if (!session) { - /* Not found? Pass to userspace to deal with */ - PRINTK(tunnel->debug, PPPOL2TP_MSG_DATA, KERN_INFO, - "%s: no socket found (%hu/%hu). Passing up.\n", - tunnel->name, tunnel_id, session_id); - goto error; - } - sock_hold(session->sock); - - /* The ref count on the socket was increased by the above call since - * we now hold a pointer to the session. Take care to do sock_put() - * when exiting this function from now on... - */ - - /* Handle the optional sequence numbers. If we are the LAC, - * enable/disable sequence numbers under the control of the LNS. If - * no sequence numbers present but we were expecting them, discard - * frame. - */ - if (hdrflags & L2TP_HDRFLAG_S) { - u16 ns, nr; - ns = ntohs(*(__be16 *) ptr); - ptr += 2; - nr = ntohs(*(__be16 *) ptr); - ptr += 2; - - /* Received a packet with sequence numbers. If we're the LNS, - * check if we sre sending sequence numbers and if not, - * configure it so. - */ - if ((!session->lns_mode) && (!session->send_seq)) { - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_INFO, - "%s: requested to enable seq numbers by LNS\n", - session->name); - session->send_seq = -1; - } - - /* Store L2TP info in the skb */ - PPPOL2TP_SKB_CB(skb)->ns = ns; - PPPOL2TP_SKB_CB(skb)->nr = nr; - PPPOL2TP_SKB_CB(skb)->has_seq = 1; - - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG, - "%s: recv data ns=%hu, nr=%hu, session nr=%hu\n", - session->name, ns, nr, session->nr); - } else { - /* No sequence numbers. - * If user has configured mandatory sequence numbers, discard. - */ - if (session->recv_seq) { - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_WARNING, - "%s: recv data has no seq numbers when required. " - "Discarding\n", session->name); - session->stats.rx_seq_discards++; - goto discard; - } - - /* If we're the LAC and we're sending sequence numbers, the - * LNS has requested that we no longer send sequence numbers. - * If we're the LNS and we're sending sequence numbers, the - * LAC is broken. Discard the frame. - */ - if ((!session->lns_mode) && (session->send_seq)) { - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_INFO, - "%s: requested to disable seq numbers by LNS\n", - session->name); - session->send_seq = 0; - } else if (session->send_seq) { - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_WARNING, - "%s: recv data has no seq numbers when required. " - "Discarding\n", session->name); - session->stats.rx_seq_discards++; - goto discard; - } - - /* Store L2TP info in the skb */ - PPPOL2TP_SKB_CB(skb)->has_seq = 0; - } - - /* If offset bit set, skip it. */ - if (hdrflags & L2TP_HDRFLAG_O) { - offset = ntohs(*(__be16 *)ptr); - ptr += 2 + offset; - } - - offset = ptr - optr; - if (!pskb_may_pull(skb, offset)) - goto discard; - - __skb_pull(skb, offset); - - /* 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)) - goto discard; - - if ((skb->data[0] == 0xff) && (skb->data[1] == 0x03)) - skb_pull(skb, 2); - - /* Prepare skb for adding to the session's reorder_q. Hold - * packets for max reorder_timeout or 1 second if not - * reordering. - */ - PPPOL2TP_SKB_CB(skb)->length = length; - PPPOL2TP_SKB_CB(skb)->expires = jiffies + - (session->reorder_timeout ? session->reorder_timeout : HZ); - - /* Add packet to the session's receive queue. Reordering is done here, if - * enabled. Saved L2TP protocol info is stored in skb->sb[]. - */ - if (PPPOL2TP_SKB_CB(skb)->has_seq) { - if (session->reorder_timeout != 0) { - /* Packet reordering enabled. Add skb to session's - * reorder queue, in order of ns. - */ - pppol2tp_recv_queue_skb(session, skb); - } else { - /* Packet reordering disabled. Discard out-of-sequence - * packets - */ - if (PPPOL2TP_SKB_CB(skb)->ns != session->nr) { - session->stats.rx_seq_discards++; - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG, - "%s: oos pkt %hu len %d discarded, " - "waiting for %hu, reorder_q_len=%d\n", - session->name, PPPOL2TP_SKB_CB(skb)->ns, - PPPOL2TP_SKB_CB(skb)->length, session->nr, - skb_queue_len(&session->reorder_q)); - goto discard; - } - skb_queue_tail(&session->reorder_q, skb); - } - } else { - /* No sequence numbers. Add the skb to the tail of the - * reorder queue. This ensures that it will be - * delivered after all previous sequenced skbs. - */ - skb_queue_tail(&session->reorder_q, skb); - } - - /* Try to dequeue as many skbs from reorder_q as we can. */ - pppol2tp_recv_dequeue(session); - sock_put(sock); - - return 0; - -discard: - session->stats.rx_errors++; - kfree_skb(skb); - sock_put(session->sock); - sock_put(sock); - - return 0; - -discard_bad_csum: - LIMIT_NETDEBUG("%s: UDP: bad checksum\n", tunnel->name); - UDP_INC_STATS_USER(&init_net, UDP_MIB_INERRORS, 0); - tunnel->stats.rx_errors++; - kfree_skb(skb); - sock_put(sock); - - return 0; - -error: - /* Put UDP header back */ - __skb_push(skb, sizeof(struct udphdr)); - sock_put(sock); - -no_tunnel: - return 1; -} - -/* UDP encapsulation receive handler. See net/ipv4/udp.c. - * Return codes: - * 0 : success. - * <0: error - * >0: skb should be passed up to userspace as UDP. - */ -static int pppol2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) -{ - struct pppol2tp_tunnel *tunnel; - - tunnel = pppol2tp_sock_to_tunnel(sk); - if (tunnel == NULL) - goto pass_up; - - PRINTK(tunnel->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG, - "%s: received %d bytes\n", tunnel->name, skb->len); - - if (pppol2tp_recv_core(sk, skb)) - goto pass_up_put; - - sock_put(sk); - return 0; - -pass_up_put: - sock_put(sk); -pass_up: - return 1; -} - -/* Receive message. This is the recvmsg for the PPPoL2TP socket. - */ -static int pppol2tp_recvmsg(struct kiocb *iocb, 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; - - msg->msg_namelen = 0; - - 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_iovec(skb, 0, msg->msg_iov, len); - if (likely(err == 0)) - err = len; - - kfree_skb(skb); -end: - return err; -} - -/************************************************************************ - * Transmit handling - ***********************************************************************/ - -/* Tell how big L2TP headers are for a particular session. This - * depends on whether sequence numbers are being used. - */ -static inline int pppol2tp_l2tp_header_len(struct pppol2tp_session *session) -{ - if (session->send_seq) - return PPPOL2TP_L2TP_HDR_SIZE_SEQ; - - return PPPOL2TP_L2TP_HDR_SIZE_NOSEQ; -} - -/* Build an L2TP header for the session into the buffer provided. - */ -static void pppol2tp_build_l2tp_header(struct pppol2tp_session *session, - void *buf) -{ - __be16 *bufp = buf; - u16 flags = L2TP_HDR_VER; - - if (session->send_seq) - flags |= L2TP_HDRFLAG_S; - - /* Setup L2TP header. - * FIXME: Can this ever be unaligned? Is direct dereferencing of - * 16-bit header fields safe here for all architectures? - */ - *bufp++ = htons(flags); - *bufp++ = htons(session->tunnel_addr.d_tunnel); - *bufp++ = htons(session->tunnel_addr.d_session); - if (session->send_seq) { - *bufp++ = htons(session->ns); - *bufp++ = 0; - session->ns++; - PRINTK(session->debug, PPPOL2TP_MSG_SEQ, KERN_DEBUG, - "%s: updated ns to %hu\n", session->name, session->ns); - } -} - -/* 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 kiocb *iocb, struct socket *sock, struct msghdr *m, - size_t total_len) -{ - static const unsigned char ppph[2] = { 0xff, 0x03 }; - struct sock *sk = sock->sk; - struct inet_sock *inet; - __wsum csum; - struct sk_buff *skb; - int error; - int hdr_len; - struct pppol2tp_session *session; - struct pppol2tp_tunnel *tunnel; - struct udphdr *uh; - unsigned int len; - struct sock *sk_tun; - u16 udp_len; - - 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; - - sk_tun = session->tunnel_sock; - tunnel = pppol2tp_sock_to_tunnel(sk_tun); - if (tunnel == NULL) - goto error_put_sess; - - /* What header length is configured for this session? */ - hdr_len = pppol2tp_l2tp_header_len(session); - - /* Allocate a socket buffer */ - error = -ENOMEM; - skb = sock_wmalloc(sk, NET_SKB_PAD + sizeof(struct iphdr) + - sizeof(struct udphdr) + 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); - - /* Build UDP header */ - inet = inet_sk(sk_tun); - udp_len = hdr_len + sizeof(ppph) + total_len; - uh = (struct udphdr *) skb->data; - uh->source = inet->inet_sport; - uh->dest = inet->inet_dport; - uh->len = htons(udp_len); - uh->check = 0; - skb_put(skb, sizeof(struct udphdr)); - - /* Build L2TP header */ - pppol2tp_build_l2tp_header(session, skb->data); - skb_put(skb, hdr_len); - - /* Add PPP header */ - skb->data[0] = ppph[0]; - skb->data[1] = ppph[1]; - skb_put(skb, 2); - - /* Copy user data into skb */ - error = memcpy_fromiovec(skb->data, m->msg_iov, total_len); - if (error < 0) { - kfree_skb(skb); - goto error_put_sess_tun; - } - skb_put(skb, total_len); - - /* Calculate UDP checksum if configured to do so */ - if (sk_tun->sk_no_check == UDP_CSUM_NOXMIT) - skb->ip_summed = CHECKSUM_NONE; - else if (!(skb_dst(skb)->dev->features & NETIF_F_V4_CSUM)) { - skb->ip_summed = CHECKSUM_COMPLETE; - csum = skb_checksum(skb, 0, udp_len, 0); - uh->check = csum_tcpudp_magic(inet->inet_saddr, - inet->inet_daddr, - udp_len, IPPROTO_UDP, csum); - if (uh->check == 0) - uh->check = CSUM_MANGLED_0; - } else { - skb->ip_summed = CHECKSUM_PARTIAL; - skb->csum_start = skb_transport_header(skb) - skb->head; - skb->csum_offset = offsetof(struct udphdr, check); - uh->check = ~csum_tcpudp_magic(inet->inet_saddr, - inet->inet_daddr, - udp_len, IPPROTO_UDP, 0); - } - - /* Debug */ - if (session->send_seq) - PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG, - "%s: send %Zd bytes, ns=%hu\n", session->name, - total_len, session->ns - 1); - else - PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG, - "%s: send %Zd bytes\n", session->name, total_len); - - if (session->debug & PPPOL2TP_MSG_DATA) { - int i; - unsigned char *datap = skb->data; - - printk(KERN_DEBUG "%s: xmit:", session->name); - for (i = 0; i < total_len; i++) { - printk(" %02X", *datap++); - if (i == 15) { - printk(" ..."); - break; - } - } - printk("\n"); - } - - /* Queue the packet to IP for output */ - len = skb->len; - error = ip_queue_xmit(skb, 1); - - /* Update stats */ - if (error >= 0) { - tunnel->stats.tx_packets++; - tunnel->stats.tx_bytes += len; - session->stats.tx_packets++; - session->stats.tx_bytes += len; - } else { - tunnel->stats.tx_errors++; - session->stats.tx_errors++; - } - - return error; - -error_put_sess_tun: - sock_put(session->tunnel_sock); -error_put_sess: - sock_put(sk); -error: - return error; -} - -/* Automatically called when the skb is freed. - */ -static void pppol2tp_sock_wfree(struct sk_buff *skb) -{ - sock_put(skb->sk); -} - -/* For data skbs that we transmit, we associate with the tunnel socket - * but don't do accounting. - */ -static inline void pppol2tp_skb_set_owner_w(struct sk_buff *skb, struct sock *sk) -{ - sock_hold(sk); - skb->sk = sk; - skb->destructor = pppol2tp_sock_wfree; -} - -/* 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; - int hdr_len; - u16 udp_len; - struct pppol2tp_session *session; - struct pppol2tp_tunnel *tunnel; - int rc; - int headroom; - int data_len = skb->len; - struct inet_sock *inet; - __wsum csum; - struct udphdr *uh; - unsigned int len; - int old_headroom; - int new_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; - - sk_tun = session->tunnel_sock; - if (sk_tun == NULL) - goto abort_put_sess; - tunnel = pppol2tp_sock_to_tunnel(sk_tun); - if (tunnel == NULL) - goto abort_put_sess; - - /* What header length is configured for this session? */ - hdr_len = pppol2tp_l2tp_header_len(session); - - /* Check that there's enough headroom in the skb to insert IP, - * UDP and L2TP and PPP headers. If not enough, expand it to - * make room. Adjust truesize. - */ - headroom = NET_SKB_PAD + sizeof(struct iphdr) + - sizeof(struct udphdr) + hdr_len + sizeof(ppph); - old_headroom = skb_headroom(skb); - if (skb_cow_head(skb, headroom)) - goto abort_put_sess_tun; - - new_headroom = skb_headroom(skb); - skb_orphan(skb); - skb->truesize += new_headroom - old_headroom; - - /* Setup PPP header */ - __skb_push(skb, sizeof(ppph)); - skb->data[0] = ppph[0]; - skb->data[1] = ppph[1]; - - /* Setup L2TP header */ - pppol2tp_build_l2tp_header(session, __skb_push(skb, hdr_len)); - - udp_len = sizeof(struct udphdr) + hdr_len + sizeof(ppph) + data_len; - - /* Setup UDP header */ - inet = inet_sk(sk_tun); - __skb_push(skb, sizeof(*uh)); - skb_reset_transport_header(skb); - uh = udp_hdr(skb); - uh->source = inet->inet_sport; - uh->dest = inet->inet_dport; - uh->len = htons(udp_len); - uh->check = 0; - - /* Debug */ - if (session->send_seq) - PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG, - "%s: send %d bytes, ns=%hu\n", session->name, - data_len, session->ns - 1); - else - PRINTK(session->debug, PPPOL2TP_MSG_DATA, KERN_DEBUG, - "%s: send %d bytes\n", session->name, data_len); - - if (session->debug & PPPOL2TP_MSG_DATA) { - int i; - unsigned char *datap = skb->data; - - printk(KERN_DEBUG "%s: xmit:", session->name); - for (i = 0; i < data_len; i++) { - printk(" %02X", *datap++); - if (i == 31) { - printk(" ..."); - break; - } - } - printk("\n"); - } - - memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); - IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | - IPSKB_REROUTED); - nf_reset(skb); - - /* Get routing info from the tunnel socket */ - skb_dst_drop(skb); - skb_dst_set(skb, dst_clone(__sk_dst_get(sk_tun))); - pppol2tp_skb_set_owner_w(skb, sk_tun); - - /* Calculate UDP checksum if configured to do so */ - if (sk_tun->sk_no_check == UDP_CSUM_NOXMIT) - skb->ip_summed = CHECKSUM_NONE; - else if ((skb_dst(skb) && skb_dst(skb)->dev) && - (!(skb_dst(skb)->dev->features & NETIF_F_V4_CSUM))) { - skb->ip_summed = CHECKSUM_COMPLETE; - csum = skb_checksum(skb, 0, udp_len, 0); - uh->check = csum_tcpudp_magic(inet->inet_saddr, - inet->inet_daddr, - udp_len, IPPROTO_UDP, csum); - if (uh->check == 0) - uh->check = CSUM_MANGLED_0; - } else { - skb->ip_summed = CHECKSUM_PARTIAL; - skb->csum_start = skb_transport_header(skb) - skb->head; - skb->csum_offset = offsetof(struct udphdr, check); - uh->check = ~csum_tcpudp_magic(inet->inet_saddr, - inet->inet_daddr, - udp_len, IPPROTO_UDP, 0); - } - - /* Queue the packet to IP for output */ - len = skb->len; - rc = ip_queue_xmit(skb, 1); - - /* Update stats */ - if (rc >= 0) { - tunnel->stats.tx_packets++; - tunnel->stats.tx_bytes += len; - session->stats.tx_packets++; - session->stats.tx_bytes += len; - } else { - tunnel->stats.tx_errors++; - session->stats.tx_errors++; - } - - 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. - *****************************************************************************/ - -/* When the tunnel UDP socket is closed, all the attached sockets need to go - * too. - */ -static void pppol2tp_tunnel_closeall(struct pppol2tp_tunnel *tunnel) -{ - int hash; - struct hlist_node *walk; - struct hlist_node *tmp; - struct pppol2tp_session *session; - struct sock *sk; - - BUG_ON(tunnel == NULL); - - PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: closing all sessions...\n", tunnel->name); - - write_lock_bh(&tunnel->hlist_lock); - for (hash = 0; hash < PPPOL2TP_HASH_SIZE; hash++) { -again: - hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) { - struct sk_buff *skb; - - session = hlist_entry(walk, struct pppol2tp_session, hlist); - - sk = session->sock; - - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: closing session\n", session->name); - - hlist_del_init(&session->hlist); - - /* Since we should hold the sock lock while - * doing any unbinding, we need to release the - * lock we're holding before taking that lock. - * Hold a reference to the sock so it doesn't - * disappear as we're jumping between locks. - */ - sock_hold(sk); - write_unlock_bh(&tunnel->hlist_lock); - lock_sock(sk); - - if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) { - pppox_unbind_sock(sk); - sk->sk_state = PPPOX_DEAD; - sk->sk_state_change(sk); - } - - /* Purge any queued data */ - skb_queue_purge(&sk->sk_receive_queue); - skb_queue_purge(&sk->sk_write_queue); - while ((skb = skb_dequeue(&session->reorder_q))) { - kfree_skb(skb); - sock_put(sk); - } - - release_sock(sk); - sock_put(sk); - - /* Now restart from the beginning of this hash - * chain. We always remove a session from the - * list so we are guaranteed to make forward - * progress. - */ - write_lock_bh(&tunnel->hlist_lock); - goto again; - } - } - write_unlock_bh(&tunnel->hlist_lock); -} - -/* Really kill the tunnel. - * Come here only when all sessions have been cleared from the tunnel. - */ -static void pppol2tp_tunnel_free(struct pppol2tp_tunnel *tunnel) -{ - struct pppol2tp_net *pn = pppol2tp_pernet(tunnel->pppol2tp_net); - - /* Remove from socket list */ - write_lock_bh(&pn->pppol2tp_tunnel_list_lock); - list_del_init(&tunnel->list); - write_unlock_bh(&pn->pppol2tp_tunnel_list_lock); - - atomic_dec(&pppol2tp_tunnel_count); - kfree(tunnel); -} - -/* Tunnel UDP socket destruct hook. - * The tunnel context is deleted only when all session sockets have been - * closed. - */ -static void pppol2tp_tunnel_destruct(struct sock *sk) -{ - struct pppol2tp_tunnel *tunnel; - - tunnel = sk->sk_user_data; - if (tunnel == NULL) - goto end; - - PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: closing...\n", tunnel->name); - - /* Close all sessions */ - pppol2tp_tunnel_closeall(tunnel); - - /* No longer an encapsulation socket. See net/ipv4/udp.c */ - (udp_sk(sk))->encap_type = 0; - (udp_sk(sk))->encap_rcv = NULL; - - /* Remove hooks into tunnel socket */ - tunnel->sock = NULL; - sk->sk_destruct = tunnel->old_sk_destruct; - sk->sk_user_data = NULL; - - /* Call original (UDP) socket descructor */ - if (sk->sk_destruct != NULL) - (*sk->sk_destruct)(sk); - - pppol2tp_tunnel_dec_refcount(tunnel); - -end: - return; -} - -/* Really kill the session socket. (Called from sock_put() if - * refcnt == 0.) - */ -static void pppol2tp_session_destruct(struct sock *sk) -{ - struct pppol2tp_session *session = NULL; - - if (sk->sk_user_data != NULL) { - struct pppol2tp_tunnel *tunnel; - - session = sk->sk_user_data; - if (session == NULL) - goto out; - - BUG_ON(session->magic != L2TP_SESSION_MAGIC); - - /* Don't use pppol2tp_sock_to_tunnel() here to - * get the tunnel context because the tunnel - * socket might have already been closed (its - * sk->sk_user_data will be NULL) so use the - * session's private tunnel ptr instead. - */ - tunnel = session->tunnel; - if (tunnel != NULL) { - BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); - - /* If session_id is zero, this is a null - * session context, which was created for a - * socket that is being used only to manage - * tunnels. - */ - if (session->tunnel_addr.s_session != 0) { - /* Delete the session socket from the - * hash - */ - write_lock_bh(&tunnel->hlist_lock); - hlist_del_init(&session->hlist); - write_unlock_bh(&tunnel->hlist_lock); - - atomic_dec(&pppol2tp_session_count); - } - - /* This will delete the tunnel context if this - * is the last session on the tunnel. - */ - session->tunnel = NULL; - session->tunnel_sock = NULL; - pppol2tp_tunnel_dec_refcount(tunnel); - } - } - - kfree(session); -out: - return; -} - -/* Called when the PPPoX socket (session) is closed. - */ -static int pppol2tp_release(struct socket *sock) -{ - struct sock *sk = sock->sk; - struct pppol2tp_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 */ - skb_queue_purge(&sk->sk_receive_queue); - skb_queue_purge(&sk->sk_write_queue); - if (session != NULL) { - struct sk_buff *skb; - while ((skb = skb_dequeue(&session->reorder_q))) { - kfree_skb(skb); - sock_put(sk); - } - sock_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; -} - -/* Internal function to prepare a tunnel (UDP) socket to have PPPoX - * sockets attached to it. - */ -static struct sock *pppol2tp_prepare_tunnel_socket(struct net *net, - int fd, u16 tunnel_id, int *error) -{ - int err; - struct socket *sock = NULL; - struct sock *sk; - struct pppol2tp_tunnel *tunnel; - struct pppol2tp_net *pn; - struct sock *ret = NULL; - - /* Get the tunnel UDP socket from the fd, which was opened by - * the userspace L2TP daemon. - */ - err = -EBADF; - sock = sockfd_lookup(fd, &err); - if (!sock) { - PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_ERR, - "tunl %hu: sockfd_lookup(fd=%d) returned %d\n", - tunnel_id, fd, err); - goto err; - } - - sk = sock->sk; - - /* Quick sanity checks */ - err = -EPROTONOSUPPORT; - if (sk->sk_protocol != IPPROTO_UDP) { - PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_ERR, - "tunl %hu: fd %d wrong protocol, got %d, expected %d\n", - tunnel_id, fd, sk->sk_protocol, IPPROTO_UDP); - goto err; - } - err = -EAFNOSUPPORT; - if (sock->ops->family != AF_INET) { - PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_ERR, - "tunl %hu: fd %d wrong family, got %d, expected %d\n", - tunnel_id, fd, sock->ops->family, AF_INET); - goto err; - } - - err = -ENOTCONN; - - /* Check if this socket has already been prepped */ - tunnel = (struct pppol2tp_tunnel *)sk->sk_user_data; - if (tunnel != NULL) { - /* User-data field already set */ - err = -EBUSY; - BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); - - /* This socket has already been prepped */ - ret = tunnel->sock; - goto out; - } - - /* This socket is available and needs prepping. Create a new tunnel - * context and init it. - */ - sk->sk_user_data = tunnel = kzalloc(sizeof(struct pppol2tp_tunnel), GFP_KERNEL); - if (sk->sk_user_data == NULL) { - err = -ENOMEM; - goto err; - } - - tunnel->magic = L2TP_TUNNEL_MAGIC; - sprintf(&tunnel->name[0], "tunl %hu", tunnel_id); - - tunnel->stats.tunnel_id = tunnel_id; - tunnel->debug = PPPOL2TP_DEFAULT_DEBUG_FLAGS; - - /* Hook on the tunnel socket destructor so that we can cleanup - * if the tunnel socket goes away. - */ - tunnel->old_sk_destruct = sk->sk_destruct; - sk->sk_destruct = pppol2tp_tunnel_destruct; - - tunnel->sock = sk; - sk->sk_allocation = GFP_ATOMIC; - - /* Misc init */ - rwlock_init(&tunnel->hlist_lock); - - /* The net we belong to */ - tunnel->pppol2tp_net = net; - pn = pppol2tp_pernet(net); - - /* Add tunnel to our list */ - INIT_LIST_HEAD(&tunnel->list); - write_lock_bh(&pn->pppol2tp_tunnel_list_lock); - list_add(&tunnel->list, &pn->pppol2tp_tunnel_list); - write_unlock_bh(&pn->pppol2tp_tunnel_list_lock); - atomic_inc(&pppol2tp_tunnel_count); - - /* Bump the reference count. The tunnel context is deleted - * only when this drops to zero. - */ - pppol2tp_tunnel_inc_refcount(tunnel); - - /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ - (udp_sk(sk))->encap_type = UDP_ENCAP_L2TPINUDP; - (udp_sk(sk))->encap_rcv = pppol2tp_udp_encap_recv; - - ret = tunnel->sock; - - *error = 0; -out: - if (sock) - sockfd_put(sock); - - return ret; - -err: - *error = err; - goto out; -} - -static struct proto pppol2tp_sk_proto = { - .name = "PPPOL2TP", - .owner = THIS_MODULE, - .obj_size = sizeof(struct pppox_sock), -}; - -/* 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_recv_core; - 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; -} - -/* 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 sock *tunnel_sock = NULL; - struct pppol2tp_session *session = NULL; - struct pppol2tp_tunnel *tunnel; - struct dst_entry *dst; - int error = 0; - - 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 */ - - /* Don't bind if s_tunnel is 0 */ - error = -EINVAL; - if (sp->pppol2tp.s_tunnel == 0) - goto end; - - /* Special case: prepare tunnel socket if s_session and - * d_session is 0. Otherwise look up tunnel using supplied - * tunnel id. - */ - if ((sp->pppol2tp.s_session == 0) && (sp->pppol2tp.d_session == 0)) { - tunnel_sock = pppol2tp_prepare_tunnel_socket(sock_net(sk), - sp->pppol2tp.fd, - sp->pppol2tp.s_tunnel, - &error); - if (tunnel_sock == NULL) - goto end; - - sock_hold(tunnel_sock); - tunnel = tunnel_sock->sk_user_data; - } else { - tunnel = pppol2tp_tunnel_find(sock_net(sk), sp->pppol2tp.s_tunnel); - - /* Error if we can't find the tunnel */ - error = -ENOENT; - if (tunnel == NULL) - goto end; - - tunnel_sock = tunnel->sock; - } - - /* Check that this session doesn't already exist */ - error = -EEXIST; - session = pppol2tp_session_find(tunnel, sp->pppol2tp.s_session); - if (session != NULL) - goto end; - - /* Allocate and initialize a new session context. */ - session = kzalloc(sizeof(struct pppol2tp_session), GFP_KERNEL); - if (session == NULL) { - error = -ENOMEM; - goto end; - } - - skb_queue_head_init(&session->reorder_q); - - session->magic = L2TP_SESSION_MAGIC; - session->owner = current->pid; - session->sock = sk; - session->tunnel = tunnel; - session->tunnel_sock = tunnel_sock; - session->tunnel_addr = sp->pppol2tp; - sprintf(&session->name[0], "sess %hu/%hu", - session->tunnel_addr.s_tunnel, - session->tunnel_addr.s_session); - - session->stats.tunnel_id = session->tunnel_addr.s_tunnel; - session->stats.session_id = session->tunnel_addr.s_session; - - INIT_HLIST_NODE(&session->hlist); - - /* Inherit debug options from tunnel */ - session->debug = tunnel->debug; - - /* Default MTU must allow space for UDP/L2TP/PPP - * headers. - */ - session->mtu = session->mru = 1500 - PPPOL2TP_HEADER_OVERHEAD; - - /* If PMTU discovery was enabled, use the MTU that was discovered */ - dst = sk_dst_get(sk); - if (dst != NULL) { - u32 pmtu = dst_mtu(__sk_dst_get(sk)); - 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. Don't add the session to the - * session hash list, just set up the internal context for use by - * ioctl() and sockopt() handlers. - */ - if ((session->tunnel_addr.s_session == 0) && - (session->tunnel_addr.d_session == 0)) { - error = 0; - sk->sk_user_data = session; - goto out_no_ppp; - } - - /* Get tunnel context from the tunnel socket */ - tunnel = pppol2tp_sock_to_tunnel(tunnel_sock); - if (tunnel == NULL) { - error = -EBADF; - goto end; - } - - /* Right now, because we don't have a way to push the incoming skb's - * straight through the UDP layer, 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_put_tun; - - /* This is how we get the session context from the socket. */ - sk->sk_user_data = session; - - /* Add session to the tunnel's hash list */ - write_lock_bh(&tunnel->hlist_lock); - hlist_add_head(&session->hlist, - pppol2tp_session_id_hash(tunnel, - session->tunnel_addr.s_session)); - write_unlock_bh(&tunnel->hlist_lock); - - atomic_inc(&pppol2tp_session_count); - -out_no_ppp: - pppol2tp_tunnel_inc_refcount(tunnel); - sk->sk_state = PPPOX_CONNECTED; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: created\n", session->name); - -end_put_tun: - sock_put(tunnel_sock); -end: - release_sock(sk); - - if (error != 0) { - if (session) - PRINTK(session->debug, - PPPOL2TP_MSG_CONTROL, KERN_WARNING, - "%s: connect failed: %d\n", - session->name, error); - else - PRINTK(-1, PPPOL2TP_MSG_CONTROL, KERN_WARNING, - "connect failed: %d\n", error); - } - - return error; -} - -/* getname() support. - */ -static int pppol2tp_getname(struct socket *sock, struct sockaddr *uaddr, - int *usockaddr_len, int peer) -{ - int len = sizeof(struct sockaddr_pppol2tp); - struct sockaddr_pppol2tp sp; - int error = 0; - struct pppol2tp_session *session; - - error = -ENOTCONN; - if (sock->sk->sk_state != PPPOX_CONNECTED) - goto end; - - session = pppol2tp_sock_to_session(sock->sk); - if (session == NULL) { - error = -EBADF; - goto end; - } - - sp.sa_family = AF_PPPOX; - sp.sa_protocol = PX_PROTO_OL2TP; - memcpy(&sp.pppol2tp, &session->tunnel_addr, - sizeof(struct pppol2tp_addr)); - - memcpy(uaddr, &sp, len); - - *usockaddr_len = len; - - error = 0; - sock_put(sock->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. - ****************************************************************************/ - -/* Session ioctl helper. - */ -static int pppol2tp_session_ioctl(struct pppol2tp_session *session, - unsigned int cmd, unsigned long arg) -{ - struct ifreq ifr; - int err = 0; - struct sock *sk = session->sock; - int val = (int) arg; - - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG, - "%s: pppol2tp_session_ioctl(cmd=%#x, arg=%#lx)\n", - session->name, cmd, arg); - - 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; - - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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; - - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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; - - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: set mru=%d\n", session->name, session->mru); - err = 0; - break; - - case PPPIOCGFLAGS: - err = -EFAULT; - if (put_user(session->flags, (int __user *) arg)) - break; - - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: get flags=%d\n", session->name, session->flags); - err = 0; - break; - - case PPPIOCSFLAGS: - err = -EFAULT; - if (get_user(val, (int __user *) arg)) - break; - session->flags = val; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: set flags=%d\n", session->name, session->flags); - err = 0; - break; - - case PPPIOCGL2TPSTATS: - err = -ENXIO; - if (!(sk->sk_state & PPPOX_CONNECTED)) - break; - - if (copy_to_user((void __user *) arg, &session->stats, - sizeof(session->stats))) - break; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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 pppol2tp_tunnel *tunnel, - unsigned int cmd, unsigned long arg) -{ - int err = 0; - struct sock *sk = tunnel->sock; - struct pppol2tp_ioc_stats stats_req; - - PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_DEBUG, - "%s: pppol2tp_tunnel_ioctl(cmd=%#x, arg=%#lx)\n", tunnel->name, - cmd, arg); - - sock_hold(sk); - - switch (cmd) { - case PPPIOCGL2TPSTATS: - err = -ENXIO; - if (!(sk->sk_state & PPPOX_CONNECTED)) - break; - - if (copy_from_user(&stats_req, (void __user *) arg, - sizeof(stats_req))) { - err = -EFAULT; - break; - } - if (stats_req.session_id != 0) { - /* resend to session ioctl handler */ - struct pppol2tp_session *session = - pppol2tp_session_find(tunnel, stats_req.session_id); - if (session != NULL) - err = pppol2tp_session_ioctl(session, cmd, arg); - else - err = -EBADR; - break; - } -#ifdef CONFIG_XFRM - tunnel->stats.using_ipsec = (sk->sk_policy[0] || sk->sk_policy[1]) ? 1 : 0; -#endif - if (copy_to_user((void __user *) arg, &tunnel->stats, - sizeof(tunnel->stats))) { - err = -EFAULT; - break; - } - PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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 pppol2tp_session *session; - struct pppol2tp_tunnel *tunnel; - 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 - */ - if ((session->tunnel_addr.s_session == 0) && - (session->tunnel_addr.d_session == 0)) { - err = -EBADF; - tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock); - if (tunnel == NULL) - goto end_put_sess; - - err = pppol2tp_tunnel_ioctl(tunnel, cmd, arg); - sock_put(session->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 pppol2tp_tunnel *tunnel, - int optname, int val) -{ - int err = 0; - - switch (optname) { - case PPPOL2TP_SO_DEBUG: - tunnel->debug = val; - PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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 pppol2tp_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; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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 = session->sock; - struct pppox_sock *po = pppox_sk(ssk); - po->chan.hdrlen = val ? PPPOL2TP_L2TP_HDR_SIZE_SEQ : - PPPOL2TP_L2TP_HDR_SIZE_NOSEQ; - } - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: set lns_mode=%d\n", session->name, - session->lns_mode); - break; - - case PPPOL2TP_SO_DEBUG: - session->debug = val; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: set debug=%x\n", session->name, session->debug); - break; - - case PPPOL2TP_SO_REORDERTO: - session->reorder_timeout = msecs_to_jiffies(val); - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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 pppol2tp_session *session = sk->sk_user_data; - struct pppol2tp_tunnel *tunnel; - int val; - int err; - - if (level != SOL_PPPOL2TP) - return udp_prot.setsockopt(sk, level, optname, optval, optlen); - - 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 - */ - if ((session->tunnel_addr.s_session == 0) && - (session->tunnel_addr.d_session == 0)) { - err = -EBADF; - tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock); - if (tunnel == NULL) - goto end_put_sess; - - err = pppol2tp_tunnel_setsockopt(sk, tunnel, optname, val); - sock_put(session->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 pppol2tp_tunnel *tunnel, - int optname, int *val) -{ - int err = 0; - - switch (optname) { - case PPPOL2TP_SO_DEBUG: - *val = tunnel->debug; - PRINTK(tunnel->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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 pppol2tp_session *session, - int optname, int *val) -{ - int err = 0; - - switch (optname) { - case PPPOL2TP_SO_RECVSEQ: - *val = session->recv_seq; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: get recv_seq=%d\n", session->name, *val); - break; - - case PPPOL2TP_SO_SENDSEQ: - *val = session->send_seq; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: get send_seq=%d\n", session->name, *val); - break; - - case PPPOL2TP_SO_LNSMODE: - *val = session->lns_mode; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: get lns_mode=%d\n", session->name, *val); - break; - - case PPPOL2TP_SO_DEBUG: - *val = session->debug; - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%s: get debug=%d\n", session->name, *val); - break; - - case PPPOL2TP_SO_REORDERTO: - *val = (int) jiffies_to_msecs(session->reorder_timeout); - PRINTK(session->debug, PPPOL2TP_MSG_CONTROL, KERN_INFO, - "%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 pppol2tp_session *session = sk->sk_user_data; - struct pppol2tp_tunnel *tunnel; - int val, len; - int err; - - if (level != SOL_PPPOL2TP) - return udp_prot.getsockopt(sk, level, optname, optval, optlen); - - if (get_user(len, (int __user *) 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 */ - if ((session->tunnel_addr.s_session == 0) && - (session->tunnel_addr.d_session == 0)) { - err = -EBADF; - tunnel = pppol2tp_sock_to_tunnel(session->tunnel_sock); - if (tunnel == NULL) - goto end_put_sess; - - err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val); - sock_put(session->tunnel_sock); - } else - err = pppol2tp_session_getsockopt(sk, session, optname, &val); - - err = -EFAULT; - if (put_user(len, (int __user *) 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 - *****************************************************************************/ - -#ifdef CONFIG_PROC_FS - -#include <linux/seq_file.h> - -struct pppol2tp_seq_data { - struct seq_net_private p; - struct pppol2tp_tunnel *tunnel; /* current tunnel */ - struct pppol2tp_session *session; /* NULL means get first session in tunnel */ -}; - -static struct pppol2tp_session *next_session(struct pppol2tp_tunnel *tunnel, struct pppol2tp_session *curr) -{ - struct pppol2tp_session *session = NULL; - struct hlist_node *walk; - int found = 0; - int next = 0; - int i; - - read_lock_bh(&tunnel->hlist_lock); - for (i = 0; i < PPPOL2TP_HASH_SIZE; i++) { - hlist_for_each_entry(session, walk, &tunnel->session_hlist[i], hlist) { - if (curr == NULL) { - found = 1; - goto out; - } - if (session == curr) { - next = 1; - continue; - } - if (next) { - found = 1; - goto out; - } - } - } -out: - read_unlock_bh(&tunnel->hlist_lock); - if (!found) - session = NULL; - - return session; -} - -static struct pppol2tp_tunnel *next_tunnel(struct pppol2tp_net *pn, - struct pppol2tp_tunnel *curr) -{ - struct pppol2tp_tunnel *tunnel = NULL; - - read_lock_bh(&pn->pppol2tp_tunnel_list_lock); - if (list_is_last(&curr->list, &pn->pppol2tp_tunnel_list)) { - goto out; - } - tunnel = list_entry(curr->list.next, struct pppol2tp_tunnel, list); -out: - read_unlock_bh(&pn->pppol2tp_tunnel_list_lock); - - return tunnel; -} - -static void *pppol2tp_seq_start(struct seq_file *m, loff_t *offs) -{ - struct pppol2tp_seq_data *pd = SEQ_START_TOKEN; - struct pppol2tp_net *pn; - loff_t pos = *offs; - - if (!pos) - goto out; - - BUG_ON(m->private == NULL); - pd = m->private; - pn = pppol2tp_pernet(seq_file_net(m)); - - if (pd->tunnel == NULL) { - if (!list_empty(&pn->pppol2tp_tunnel_list)) - pd->tunnel = list_entry(pn->pppol2tp_tunnel_list.next, struct pppol2tp_tunnel, list); - } else { - pd->session = next_session(pd->tunnel, pd->session); - if (pd->session == NULL) { - pd->tunnel = next_tunnel(pn, pd->tunnel); - } - } - - /* 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 pppol2tp_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 %llu/%llu/%llu %llu/%llu/%llu\n", - tunnel->debug, - (unsigned long long)tunnel->stats.tx_packets, - (unsigned long long)tunnel->stats.tx_bytes, - (unsigned long long)tunnel->stats.tx_errors, - (unsigned long long)tunnel->stats.rx_packets, - (unsigned long long)tunnel->stats.rx_bytes, - (unsigned long long)tunnel->stats.rx_errors); -} - -static void pppol2tp_seq_session_show(struct seq_file *m, void *v) -{ - struct pppol2tp_session *session = v; - - seq_printf(m, " SESSION '%s' %08X/%d %04X/%04X -> " - "%04X/%04X %d %c\n", - session->name, - ntohl(session->tunnel_addr.addr.sin_addr.s_addr), - ntohs(session->tunnel_addr.addr.sin_port), - session->tunnel_addr.s_tunnel, - session->tunnel_addr.s_session, - session->tunnel_addr.d_tunnel, - session->tunnel_addr.d_session, - session->sock->sk_state, - (session == session->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 %llu/%llu/%llu %llu/%llu/%llu\n", - session->nr, session->ns, - (unsigned long long)session->stats.tx_packets, - (unsigned long long)session->stats.tx_bytes, - (unsigned long long)session->stats.tx_errors, - (unsigned long long)session->stats.rx_packets, - (unsigned long long)session->stats.rx_bytes, - (unsigned long long)session->stats.rx_errors); -} - -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 */ - -/***************************************************************************** - * 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 struct pppox_proto pppol2tp_proto = { - .create = pppol2tp_create, - .ioctl = pppol2tp_ioctl -}; - -static __net_init int pppol2tp_init_net(struct net *net) -{ - struct pppol2tp_net *pn = pppol2tp_pernet(net); - struct proc_dir_entry *pde; - - INIT_LIST_HEAD(&pn->pppol2tp_tunnel_list); - rwlock_init(&pn->pppol2tp_tunnel_list_lock); - - pde = proc_net_fops_create(net, "pppol2tp", S_IRUGO, &pppol2tp_proc_fops); -#ifdef CONFIG_PROC_FS - if (!pde) - return -ENOMEM; -#endif - - return 0; -} - -static __net_exit void pppol2tp_exit_net(struct net *net) -{ - proc_net_remove(net, "pppol2tp"); -} - -static struct pernet_operations pppol2tp_net_ops = { - .init = pppol2tp_init_net, - .exit = pppol2tp_exit_net, - .id = &pppol2tp_net_id, - .size = sizeof(struct pppol2tp_net), -}; - -static int __init pppol2tp_init(void) -{ - int err; - - err = proto_register(&pppol2tp_sk_proto, 0); - if (err) - goto out; - err = register_pppox_proto(PX_PROTO_OL2TP, &pppol2tp_proto); - if (err) - goto out_unregister_pppol2tp_proto; - - err = register_pernet_device(&pppol2tp_net_ops); - if (err) - goto out_unregister_pppox_proto; - - printk(KERN_INFO "PPPoL2TP kernel driver, %s\n", - PPPOL2TP_DRV_VERSION); - -out: - return err; -out_unregister_pppox_proto: - unregister_pppox_proto(PX_PROTO_OL2TP); -out_unregister_pppol2tp_proto: - proto_unregister(&pppol2tp_sk_proto); - goto out; -} - -static void __exit pppol2tp_exit(void) -{ - unregister_pppox_proto(PX_PROTO_OL2TP); - unregister_pernet_device(&pppol2tp_net_ops); - proto_unregister(&pppol2tp_sk_proto); -} - -module_init(pppol2tp_init); -module_exit(pppol2tp_exit); - -MODULE_AUTHOR("Martijn van Oosterhout <kleptog@svana.org>, " - "James Chapman <jchapman@katalix.com>"); -MODULE_DESCRIPTION("PPP over L2TP over UDP"); -MODULE_LICENSE("GPL"); -MODULE_VERSION(PPPOL2TP_DRV_VERSION); |