1fd558d18SJames Chapman /* 2fd558d18SJames Chapman * L2TP core. 3fd558d18SJames Chapman * 4fd558d18SJames Chapman * Copyright (c) 2008,2009,2010 Katalix Systems Ltd 5fd558d18SJames Chapman * 6fd558d18SJames Chapman * This file contains some code of the original L2TPv2 pppol2tp 7fd558d18SJames Chapman * driver, which has the following copyright: 8fd558d18SJames Chapman * 9fd558d18SJames Chapman * Authors: Martijn van Oosterhout <kleptog@svana.org> 10fd558d18SJames Chapman * James Chapman (jchapman@katalix.com) 11fd558d18SJames Chapman * Contributors: 12fd558d18SJames Chapman * Michal Ostrowski <mostrows@speakeasy.net> 13fd558d18SJames Chapman * Arnaldo Carvalho de Melo <acme@xconectiva.com.br> 14fd558d18SJames Chapman * David S. Miller (davem@redhat.com) 15fd558d18SJames Chapman * 16fd558d18SJames Chapman * This program is free software; you can redistribute it and/or modify 17fd558d18SJames Chapman * it under the terms of the GNU General Public License version 2 as 18fd558d18SJames Chapman * published by the Free Software Foundation. 19fd558d18SJames Chapman */ 20fd558d18SJames Chapman 21a4ca44faSJoe Perches #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 22a4ca44faSJoe Perches 23fd558d18SJames Chapman #include <linux/module.h> 24fd558d18SJames Chapman #include <linux/string.h> 25fd558d18SJames Chapman #include <linux/list.h> 26e02d494dSJames Chapman #include <linux/rculist.h> 27fd558d18SJames Chapman #include <linux/uaccess.h> 28fd558d18SJames Chapman 29fd558d18SJames Chapman #include <linux/kernel.h> 30fd558d18SJames Chapman #include <linux/spinlock.h> 31fd558d18SJames Chapman #include <linux/kthread.h> 32fd558d18SJames Chapman #include <linux/sched.h> 33fd558d18SJames Chapman #include <linux/slab.h> 34fd558d18SJames Chapman #include <linux/errno.h> 35fd558d18SJames Chapman #include <linux/jiffies.h> 36fd558d18SJames Chapman 37fd558d18SJames Chapman #include <linux/netdevice.h> 38fd558d18SJames Chapman #include <linux/net.h> 39fd558d18SJames Chapman #include <linux/inetdevice.h> 40fd558d18SJames Chapman #include <linux/skbuff.h> 41fd558d18SJames Chapman #include <linux/init.h> 420d76751fSJames Chapman #include <linux/in.h> 43fd558d18SJames Chapman #include <linux/ip.h> 44fd558d18SJames Chapman #include <linux/udp.h> 450d76751fSJames Chapman #include <linux/l2tp.h> 46fd558d18SJames Chapman #include <linux/hash.h> 47fd558d18SJames Chapman #include <linux/sort.h> 48fd558d18SJames Chapman #include <linux/file.h> 49fd558d18SJames Chapman #include <linux/nsproxy.h> 50fd558d18SJames Chapman #include <net/net_namespace.h> 51fd558d18SJames Chapman #include <net/netns/generic.h> 52fd558d18SJames Chapman #include <net/dst.h> 53fd558d18SJames Chapman #include <net/ip.h> 54fd558d18SJames Chapman #include <net/udp.h> 5585644b4dSTom Herbert #include <net/udp_tunnel.h> 56309795f4SJames Chapman #include <net/inet_common.h> 57fd558d18SJames Chapman #include <net/xfrm.h> 580d76751fSJames Chapman #include <net/protocol.h> 59d2cf3361SBenjamin LaHaise #include <net/inet6_connection_sock.h> 60d2cf3361SBenjamin LaHaise #include <net/inet_ecn.h> 61d2cf3361SBenjamin LaHaise #include <net/ip6_route.h> 62d499bd2eSDavid S. Miller #include <net/ip6_checksum.h> 63fd558d18SJames Chapman 64fd558d18SJames Chapman #include <asm/byteorder.h> 6560063497SArun Sharma #include <linux/atomic.h> 66fd558d18SJames Chapman 67fd558d18SJames Chapman #include "l2tp_core.h" 68fd558d18SJames Chapman 69fd558d18SJames Chapman #define L2TP_DRV_VERSION "V2.0" 70fd558d18SJames Chapman 71fd558d18SJames Chapman /* L2TP header constants */ 72fd558d18SJames Chapman #define L2TP_HDRFLAG_T 0x8000 73fd558d18SJames Chapman #define L2TP_HDRFLAG_L 0x4000 74fd558d18SJames Chapman #define L2TP_HDRFLAG_S 0x0800 75fd558d18SJames Chapman #define L2TP_HDRFLAG_O 0x0200 76fd558d18SJames Chapman #define L2TP_HDRFLAG_P 0x0100 77fd558d18SJames Chapman 78fd558d18SJames Chapman #define L2TP_HDR_VER_MASK 0x000F 79fd558d18SJames Chapman #define L2TP_HDR_VER_2 0x0002 80f7faffa3SJames Chapman #define L2TP_HDR_VER_3 0x0003 81fd558d18SJames Chapman 82fd558d18SJames Chapman /* L2TPv3 default L2-specific sublayer */ 83fd558d18SJames Chapman #define L2TP_SLFLAG_S 0x40000000 84fd558d18SJames Chapman #define L2TP_SL_SEQ_MASK 0x00ffffff 85fd558d18SJames Chapman 86fd558d18SJames Chapman #define L2TP_HDR_SIZE_SEQ 10 87fd558d18SJames Chapman #define L2TP_HDR_SIZE_NOSEQ 6 88fd558d18SJames Chapman 89fd558d18SJames Chapman /* Default trace flags */ 90fd558d18SJames Chapman #define L2TP_DEFAULT_DEBUG_FLAGS 0 91fd558d18SJames Chapman 92fd558d18SJames Chapman /* Private data stored for received packets in the skb. 93fd558d18SJames Chapman */ 94fd558d18SJames Chapman struct l2tp_skb_cb { 95f7faffa3SJames Chapman u32 ns; 96fd558d18SJames Chapman u16 has_seq; 97fd558d18SJames Chapman u16 length; 98fd558d18SJames Chapman unsigned long expires; 99fd558d18SJames Chapman }; 100fd558d18SJames Chapman 101fd558d18SJames Chapman #define L2TP_SKB_CB(skb) ((struct l2tp_skb_cb *) &skb->cb[sizeof(struct inet_skb_parm)]) 102fd558d18SJames Chapman 103fd558d18SJames Chapman static atomic_t l2tp_tunnel_count; 104fd558d18SJames Chapman static atomic_t l2tp_session_count; 105f8ccac0eSTom Parkin static struct workqueue_struct *l2tp_wq; 106fd558d18SJames Chapman 107fd558d18SJames Chapman /* per-net private data for this module */ 108fd558d18SJames Chapman static unsigned int l2tp_net_id; 109fd558d18SJames Chapman struct l2tp_net { 110fd558d18SJames Chapman struct list_head l2tp_tunnel_list; 111e02d494dSJames Chapman spinlock_t l2tp_tunnel_list_lock; 112f7faffa3SJames Chapman struct hlist_head l2tp_session_hlist[L2TP_HASH_SIZE_2]; 113e02d494dSJames Chapman spinlock_t l2tp_session_hlist_lock; 114fd558d18SJames Chapman }; 115fd558d18SJames Chapman 116fc130840Sstephen hemminger 1178d8a51e2SDavid S. Miller static inline struct l2tp_tunnel *l2tp_tunnel(struct sock *sk) 1188d8a51e2SDavid S. Miller { 1198d8a51e2SDavid S. Miller return sk->sk_user_data; 1208d8a51e2SDavid S. Miller } 1218d8a51e2SDavid S. Miller 1229aaef50cSGuillaume Nault static inline struct l2tp_net *l2tp_pernet(const struct net *net) 123fd558d18SJames Chapman { 124fd558d18SJames Chapman BUG_ON(!net); 125fd558d18SJames Chapman 126fd558d18SJames Chapman return net_generic(net, l2tp_net_id); 127fd558d18SJames Chapman } 128fd558d18SJames Chapman 129f7faffa3SJames Chapman /* Session hash global list for L2TPv3. 130f7faffa3SJames Chapman * The session_id SHOULD be random according to RFC3931, but several 131f7faffa3SJames Chapman * L2TP implementations use incrementing session_ids. So we do a real 132f7faffa3SJames Chapman * hash on the session_id, rather than a simple bitmask. 133f7faffa3SJames Chapman */ 134f7faffa3SJames Chapman static inline struct hlist_head * 135f7faffa3SJames Chapman l2tp_session_id_hash_2(struct l2tp_net *pn, u32 session_id) 136f7faffa3SJames Chapman { 137f7faffa3SJames Chapman return &pn->l2tp_session_hlist[hash_32(session_id, L2TP_HASH_BITS_2)]; 138f7faffa3SJames Chapman 139f7faffa3SJames Chapman } 140f7faffa3SJames Chapman 14180d84ef3STom Parkin /* Lookup the tunnel socket, possibly involving the fs code if the socket is 14280d84ef3STom Parkin * owned by userspace. A struct sock returned from this function must be 14380d84ef3STom Parkin * released using l2tp_tunnel_sock_put once you're done with it. 14480d84ef3STom Parkin */ 145b5d2b285Sstephen hemminger static struct sock *l2tp_tunnel_sock_lookup(struct l2tp_tunnel *tunnel) 14680d84ef3STom Parkin { 14780d84ef3STom Parkin int err = 0; 14880d84ef3STom Parkin struct socket *sock = NULL; 14980d84ef3STom Parkin struct sock *sk = NULL; 15080d84ef3STom Parkin 15180d84ef3STom Parkin if (!tunnel) 15280d84ef3STom Parkin goto out; 15380d84ef3STom Parkin 15480d84ef3STom Parkin if (tunnel->fd >= 0) { 15580d84ef3STom Parkin /* Socket is owned by userspace, who might be in the process 15680d84ef3STom Parkin * of closing it. Look the socket up using the fd to ensure 15780d84ef3STom Parkin * consistency. 15880d84ef3STom Parkin */ 15980d84ef3STom Parkin sock = sockfd_lookup(tunnel->fd, &err); 16080d84ef3STom Parkin if (sock) 16180d84ef3STom Parkin sk = sock->sk; 16280d84ef3STom Parkin } else { 16380d84ef3STom Parkin /* Socket is owned by kernelspace */ 16480d84ef3STom Parkin sk = tunnel->sock; 1658abbbe8fSTom Parkin sock_hold(sk); 16680d84ef3STom Parkin } 16780d84ef3STom Parkin 16880d84ef3STom Parkin out: 16980d84ef3STom Parkin return sk; 17080d84ef3STom Parkin } 17180d84ef3STom Parkin 17280d84ef3STom Parkin /* Drop a reference to a tunnel socket obtained via. l2tp_tunnel_sock_put */ 173b5d2b285Sstephen hemminger static void l2tp_tunnel_sock_put(struct sock *sk) 17480d84ef3STom Parkin { 17580d84ef3STom Parkin struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk); 17680d84ef3STom Parkin if (tunnel) { 17780d84ef3STom Parkin if (tunnel->fd >= 0) { 17880d84ef3STom Parkin /* Socket is owned by userspace */ 17980d84ef3STom Parkin sockfd_put(sk->sk_socket); 18080d84ef3STom Parkin } 18180d84ef3STom Parkin sock_put(sk); 18280d84ef3STom Parkin } 1838abbbe8fSTom Parkin sock_put(sk); 18480d84ef3STom Parkin } 18580d84ef3STom Parkin 186fd558d18SJames Chapman /* Session hash list. 187fd558d18SJames Chapman * The session_id SHOULD be random according to RFC2661, but several 188fd558d18SJames Chapman * L2TP implementations (Cisco and Microsoft) use incrementing 189fd558d18SJames Chapman * session_ids. So we do a real hash on the session_id, rather than a 190fd558d18SJames Chapman * simple bitmask. 191fd558d18SJames Chapman */ 192fd558d18SJames Chapman static inline struct hlist_head * 193fd558d18SJames Chapman l2tp_session_id_hash(struct l2tp_tunnel *tunnel, u32 session_id) 194fd558d18SJames Chapman { 195fd558d18SJames Chapman return &tunnel->session_hlist[hash_32(session_id, L2TP_HASH_BITS)]; 196fd558d18SJames Chapman } 197fd558d18SJames Chapman 19854652eb1SGuillaume Nault /* Lookup a tunnel. A new reference is held on the returned tunnel. */ 19954652eb1SGuillaume Nault struct l2tp_tunnel *l2tp_tunnel_get(const struct net *net, u32 tunnel_id) 20054652eb1SGuillaume Nault { 20154652eb1SGuillaume Nault const struct l2tp_net *pn = l2tp_pernet(net); 20254652eb1SGuillaume Nault struct l2tp_tunnel *tunnel; 20354652eb1SGuillaume Nault 20454652eb1SGuillaume Nault rcu_read_lock_bh(); 20554652eb1SGuillaume Nault list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { 20654652eb1SGuillaume Nault if (tunnel->tunnel_id == tunnel_id) { 20754652eb1SGuillaume Nault l2tp_tunnel_inc_refcount(tunnel); 20854652eb1SGuillaume Nault rcu_read_unlock_bh(); 20954652eb1SGuillaume Nault 21054652eb1SGuillaume Nault return tunnel; 21154652eb1SGuillaume Nault } 21254652eb1SGuillaume Nault } 21354652eb1SGuillaume Nault rcu_read_unlock_bh(); 21454652eb1SGuillaume Nault 21554652eb1SGuillaume Nault return NULL; 21654652eb1SGuillaume Nault } 21754652eb1SGuillaume Nault EXPORT_SYMBOL_GPL(l2tp_tunnel_get); 21854652eb1SGuillaume Nault 21955a3ce3bSGuillaume Nault /* Lookup a session. A new reference is held on the returned session. 22061b9a047SGuillaume Nault * Optionally calls session->ref() too if do_ref is true. 22161b9a047SGuillaume Nault */ 2229aaef50cSGuillaume Nault struct l2tp_session *l2tp_session_get(const struct net *net, 22361b9a047SGuillaume Nault struct l2tp_tunnel *tunnel, 22461b9a047SGuillaume Nault u32 session_id, bool do_ref) 22561b9a047SGuillaume Nault { 22661b9a047SGuillaume Nault struct hlist_head *session_list; 22761b9a047SGuillaume Nault struct l2tp_session *session; 22861b9a047SGuillaume Nault 22961b9a047SGuillaume Nault if (!tunnel) { 23061b9a047SGuillaume Nault struct l2tp_net *pn = l2tp_pernet(net); 23161b9a047SGuillaume Nault 23261b9a047SGuillaume Nault session_list = l2tp_session_id_hash_2(pn, session_id); 23361b9a047SGuillaume Nault 23461b9a047SGuillaume Nault rcu_read_lock_bh(); 23561b9a047SGuillaume Nault hlist_for_each_entry_rcu(session, session_list, global_hlist) { 23661b9a047SGuillaume Nault if (session->session_id == session_id) { 23761b9a047SGuillaume Nault l2tp_session_inc_refcount(session); 23861b9a047SGuillaume Nault if (do_ref && session->ref) 23961b9a047SGuillaume Nault session->ref(session); 24061b9a047SGuillaume Nault rcu_read_unlock_bh(); 24161b9a047SGuillaume Nault 24261b9a047SGuillaume Nault return session; 24361b9a047SGuillaume Nault } 24461b9a047SGuillaume Nault } 24561b9a047SGuillaume Nault rcu_read_unlock_bh(); 24661b9a047SGuillaume Nault 24761b9a047SGuillaume Nault return NULL; 24861b9a047SGuillaume Nault } 24961b9a047SGuillaume Nault 25061b9a047SGuillaume Nault session_list = l2tp_session_id_hash(tunnel, session_id); 25161b9a047SGuillaume Nault read_lock_bh(&tunnel->hlist_lock); 25261b9a047SGuillaume Nault hlist_for_each_entry(session, session_list, hlist) { 25361b9a047SGuillaume Nault if (session->session_id == session_id) { 25461b9a047SGuillaume Nault l2tp_session_inc_refcount(session); 25561b9a047SGuillaume Nault if (do_ref && session->ref) 25661b9a047SGuillaume Nault session->ref(session); 25761b9a047SGuillaume Nault read_unlock_bh(&tunnel->hlist_lock); 25861b9a047SGuillaume Nault 25961b9a047SGuillaume Nault return session; 26061b9a047SGuillaume Nault } 26161b9a047SGuillaume Nault } 26261b9a047SGuillaume Nault read_unlock_bh(&tunnel->hlist_lock); 26361b9a047SGuillaume Nault 26461b9a047SGuillaume Nault return NULL; 26561b9a047SGuillaume Nault } 26661b9a047SGuillaume Nault EXPORT_SYMBOL_GPL(l2tp_session_get); 26761b9a047SGuillaume Nault 268e08293a4SGuillaume Nault struct l2tp_session *l2tp_session_get_nth(struct l2tp_tunnel *tunnel, int nth, 269e08293a4SGuillaume Nault bool do_ref) 270fd558d18SJames Chapman { 271fd558d18SJames Chapman int hash; 272fd558d18SJames Chapman struct l2tp_session *session; 273fd558d18SJames Chapman int count = 0; 274fd558d18SJames Chapman 275fd558d18SJames Chapman read_lock_bh(&tunnel->hlist_lock); 276fd558d18SJames Chapman for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { 277b67bfe0dSSasha Levin hlist_for_each_entry(session, &tunnel->session_hlist[hash], hlist) { 278fd558d18SJames Chapman if (++count > nth) { 279e08293a4SGuillaume Nault l2tp_session_inc_refcount(session); 280e08293a4SGuillaume Nault if (do_ref && session->ref) 281e08293a4SGuillaume Nault session->ref(session); 282fd558d18SJames Chapman read_unlock_bh(&tunnel->hlist_lock); 283fd558d18SJames Chapman return session; 284fd558d18SJames Chapman } 285fd558d18SJames Chapman } 286fd558d18SJames Chapman } 287fd558d18SJames Chapman 288fd558d18SJames Chapman read_unlock_bh(&tunnel->hlist_lock); 289fd558d18SJames Chapman 290fd558d18SJames Chapman return NULL; 291fd558d18SJames Chapman } 292e08293a4SGuillaume Nault EXPORT_SYMBOL_GPL(l2tp_session_get_nth); 293fd558d18SJames Chapman 294309795f4SJames Chapman /* Lookup a session by interface name. 295309795f4SJames Chapman * This is very inefficient but is only used by management interfaces. 296309795f4SJames Chapman */ 2979aaef50cSGuillaume Nault struct l2tp_session *l2tp_session_get_by_ifname(const struct net *net, 2989aaef50cSGuillaume Nault const char *ifname, 2992777e2abSGuillaume Nault bool do_ref) 300309795f4SJames Chapman { 301309795f4SJames Chapman struct l2tp_net *pn = l2tp_pernet(net); 302309795f4SJames Chapman int hash; 303309795f4SJames Chapman struct l2tp_session *session; 304309795f4SJames Chapman 305e02d494dSJames Chapman rcu_read_lock_bh(); 306309795f4SJames Chapman for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) { 307b67bfe0dSSasha Levin hlist_for_each_entry_rcu(session, &pn->l2tp_session_hlist[hash], global_hlist) { 308309795f4SJames Chapman if (!strcmp(session->ifname, ifname)) { 3092777e2abSGuillaume Nault l2tp_session_inc_refcount(session); 3102777e2abSGuillaume Nault if (do_ref && session->ref) 3112777e2abSGuillaume Nault session->ref(session); 312e02d494dSJames Chapman rcu_read_unlock_bh(); 3132777e2abSGuillaume Nault 314309795f4SJames Chapman return session; 315309795f4SJames Chapman } 316309795f4SJames Chapman } 317309795f4SJames Chapman } 318309795f4SJames Chapman 319e02d494dSJames Chapman rcu_read_unlock_bh(); 320309795f4SJames Chapman 321309795f4SJames Chapman return NULL; 322309795f4SJames Chapman } 3232777e2abSGuillaume Nault EXPORT_SYMBOL_GPL(l2tp_session_get_by_ifname); 324309795f4SJames Chapman 325dbdbc73bSGuillaume Nault static int l2tp_session_add_to_tunnel(struct l2tp_tunnel *tunnel, 326dbdbc73bSGuillaume Nault struct l2tp_session *session) 327dbdbc73bSGuillaume Nault { 328dbdbc73bSGuillaume Nault struct l2tp_session *session_walk; 329dbdbc73bSGuillaume Nault struct hlist_head *g_head; 330dbdbc73bSGuillaume Nault struct hlist_head *head; 331dbdbc73bSGuillaume Nault struct l2tp_net *pn; 332dbdbc73bSGuillaume Nault 333dbdbc73bSGuillaume Nault head = l2tp_session_id_hash(tunnel, session->session_id); 334dbdbc73bSGuillaume Nault 335dbdbc73bSGuillaume Nault write_lock_bh(&tunnel->hlist_lock); 336dbdbc73bSGuillaume Nault hlist_for_each_entry(session_walk, head, hlist) 337dbdbc73bSGuillaume Nault if (session_walk->session_id == session->session_id) 338dbdbc73bSGuillaume Nault goto exist; 339dbdbc73bSGuillaume Nault 340dbdbc73bSGuillaume Nault if (tunnel->version == L2TP_HDR_VER_3) { 341dbdbc73bSGuillaume Nault pn = l2tp_pernet(tunnel->l2tp_net); 342dbdbc73bSGuillaume Nault g_head = l2tp_session_id_hash_2(l2tp_pernet(tunnel->l2tp_net), 343dbdbc73bSGuillaume Nault session->session_id); 344dbdbc73bSGuillaume Nault 345dbdbc73bSGuillaume Nault spin_lock_bh(&pn->l2tp_session_hlist_lock); 346dbdbc73bSGuillaume Nault hlist_for_each_entry(session_walk, g_head, global_hlist) 347dbdbc73bSGuillaume Nault if (session_walk->session_id == session->session_id) 348dbdbc73bSGuillaume Nault goto exist_glob; 349dbdbc73bSGuillaume Nault 350dbdbc73bSGuillaume Nault hlist_add_head_rcu(&session->global_hlist, g_head); 351dbdbc73bSGuillaume Nault spin_unlock_bh(&pn->l2tp_session_hlist_lock); 352dbdbc73bSGuillaume Nault } 353dbdbc73bSGuillaume Nault 354dbdbc73bSGuillaume Nault hlist_add_head(&session->hlist, head); 355dbdbc73bSGuillaume Nault write_unlock_bh(&tunnel->hlist_lock); 356dbdbc73bSGuillaume Nault 357dbdbc73bSGuillaume Nault return 0; 358dbdbc73bSGuillaume Nault 359dbdbc73bSGuillaume Nault exist_glob: 360dbdbc73bSGuillaume Nault spin_unlock_bh(&pn->l2tp_session_hlist_lock); 361dbdbc73bSGuillaume Nault exist: 362dbdbc73bSGuillaume Nault write_unlock_bh(&tunnel->hlist_lock); 363dbdbc73bSGuillaume Nault 364dbdbc73bSGuillaume Nault return -EEXIST; 365dbdbc73bSGuillaume Nault } 366dbdbc73bSGuillaume Nault 367fd558d18SJames Chapman /* Lookup a tunnel by id 368fd558d18SJames Chapman */ 3692f858b92SGuillaume Nault struct l2tp_tunnel *l2tp_tunnel_find(const struct net *net, u32 tunnel_id) 370fd558d18SJames Chapman { 371fd558d18SJames Chapman struct l2tp_tunnel *tunnel; 372fd558d18SJames Chapman struct l2tp_net *pn = l2tp_pernet(net); 373fd558d18SJames Chapman 374e02d494dSJames Chapman rcu_read_lock_bh(); 375e02d494dSJames Chapman list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { 376fd558d18SJames Chapman if (tunnel->tunnel_id == tunnel_id) { 377e02d494dSJames Chapman rcu_read_unlock_bh(); 378fd558d18SJames Chapman return tunnel; 379fd558d18SJames Chapman } 380fd558d18SJames Chapman } 381e02d494dSJames Chapman rcu_read_unlock_bh(); 382fd558d18SJames Chapman 383fd558d18SJames Chapman return NULL; 384fd558d18SJames Chapman } 385fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_tunnel_find); 386fd558d18SJames Chapman 3872f858b92SGuillaume Nault struct l2tp_tunnel *l2tp_tunnel_find_nth(const struct net *net, int nth) 388fd558d18SJames Chapman { 389fd558d18SJames Chapman struct l2tp_net *pn = l2tp_pernet(net); 390fd558d18SJames Chapman struct l2tp_tunnel *tunnel; 391fd558d18SJames Chapman int count = 0; 392fd558d18SJames Chapman 393e02d494dSJames Chapman rcu_read_lock_bh(); 394e02d494dSJames Chapman list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { 395fd558d18SJames Chapman if (++count > nth) { 396e02d494dSJames Chapman rcu_read_unlock_bh(); 397fd558d18SJames Chapman return tunnel; 398fd558d18SJames Chapman } 399fd558d18SJames Chapman } 400fd558d18SJames Chapman 401e02d494dSJames Chapman rcu_read_unlock_bh(); 402fd558d18SJames Chapman 403fd558d18SJames Chapman return NULL; 404fd558d18SJames Chapman } 405fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_tunnel_find_nth); 406fd558d18SJames Chapman 407fd558d18SJames Chapman /***************************************************************************** 408fd558d18SJames Chapman * Receive data handling 409fd558d18SJames Chapman *****************************************************************************/ 410fd558d18SJames Chapman 411fd558d18SJames Chapman /* Queue a skb in order. We come here only if the skb has an L2TP sequence 412fd558d18SJames Chapman * number. 413fd558d18SJames Chapman */ 414fd558d18SJames Chapman static void l2tp_recv_queue_skb(struct l2tp_session *session, struct sk_buff *skb) 415fd558d18SJames Chapman { 416fd558d18SJames Chapman struct sk_buff *skbp; 417fd558d18SJames Chapman struct sk_buff *tmp; 418f7faffa3SJames Chapman u32 ns = L2TP_SKB_CB(skb)->ns; 419fd558d18SJames Chapman 420fd558d18SJames Chapman spin_lock_bh(&session->reorder_q.lock); 421fd558d18SJames Chapman skb_queue_walk_safe(&session->reorder_q, skbp, tmp) { 422fd558d18SJames Chapman if (L2TP_SKB_CB(skbp)->ns > ns) { 423fd558d18SJames Chapman __skb_queue_before(&session->reorder_q, skbp, skb); 424a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 425fd558d18SJames Chapman "%s: pkt %hu, inserted before %hu, reorder_q len=%d\n", 426fd558d18SJames Chapman session->name, ns, L2TP_SKB_CB(skbp)->ns, 427fd558d18SJames Chapman skb_queue_len(&session->reorder_q)); 4287b7c0719STom Parkin atomic_long_inc(&session->stats.rx_oos_packets); 429fd558d18SJames Chapman goto out; 430fd558d18SJames Chapman } 431fd558d18SJames Chapman } 432fd558d18SJames Chapman 433fd558d18SJames Chapman __skb_queue_tail(&session->reorder_q, skb); 434fd558d18SJames Chapman 435fd558d18SJames Chapman out: 436fd558d18SJames Chapman spin_unlock_bh(&session->reorder_q.lock); 437fd558d18SJames Chapman } 438fd558d18SJames Chapman 439fd558d18SJames Chapman /* Dequeue a single skb. 440fd558d18SJames Chapman */ 441fd558d18SJames Chapman static void l2tp_recv_dequeue_skb(struct l2tp_session *session, struct sk_buff *skb) 442fd558d18SJames Chapman { 443fd558d18SJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 444fd558d18SJames Chapman int length = L2TP_SKB_CB(skb)->length; 445fd558d18SJames Chapman 446fd558d18SJames Chapman /* We're about to requeue the skb, so return resources 447fd558d18SJames Chapman * to its current owner (a socket receive buffer). 448fd558d18SJames Chapman */ 449fd558d18SJames Chapman skb_orphan(skb); 450fd558d18SJames Chapman 4517b7c0719STom Parkin atomic_long_inc(&tunnel->stats.rx_packets); 4527b7c0719STom Parkin atomic_long_add(length, &tunnel->stats.rx_bytes); 4537b7c0719STom Parkin atomic_long_inc(&session->stats.rx_packets); 4547b7c0719STom Parkin atomic_long_add(length, &session->stats.rx_bytes); 455fd558d18SJames Chapman 456fd558d18SJames Chapman if (L2TP_SKB_CB(skb)->has_seq) { 457fd558d18SJames Chapman /* Bump our Nr */ 458fd558d18SJames Chapman session->nr++; 4598a1631d5SJames Chapman session->nr &= session->nr_max; 460f7faffa3SJames Chapman 461a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, "%s: updated nr to %hu\n", 462a4ca44faSJoe Perches session->name, session->nr); 463fd558d18SJames Chapman } 464fd558d18SJames Chapman 465fd558d18SJames Chapman /* call private receive handler */ 466fd558d18SJames Chapman if (session->recv_skb != NULL) 467fd558d18SJames Chapman (*session->recv_skb)(session, skb, L2TP_SKB_CB(skb)->length); 468fd558d18SJames Chapman else 469fd558d18SJames Chapman kfree_skb(skb); 470fd558d18SJames Chapman 471fd558d18SJames Chapman if (session->deref) 472fd558d18SJames Chapman (*session->deref)(session); 473fd558d18SJames Chapman } 474fd558d18SJames Chapman 475fd558d18SJames Chapman /* Dequeue skbs from the session's reorder_q, subject to packet order. 476fd558d18SJames Chapman * Skbs that have been in the queue for too long are simply discarded. 477fd558d18SJames Chapman */ 478fd558d18SJames Chapman static void l2tp_recv_dequeue(struct l2tp_session *session) 479fd558d18SJames Chapman { 480fd558d18SJames Chapman struct sk_buff *skb; 481fd558d18SJames Chapman struct sk_buff *tmp; 482fd558d18SJames Chapman 483fd558d18SJames Chapman /* If the pkt at the head of the queue has the nr that we 484fd558d18SJames Chapman * expect to send up next, dequeue it and any other 485fd558d18SJames Chapman * in-sequence packets behind it. 486fd558d18SJames Chapman */ 487e2e210c0SEric Dumazet start: 488fd558d18SJames Chapman spin_lock_bh(&session->reorder_q.lock); 489fd558d18SJames Chapman skb_queue_walk_safe(&session->reorder_q, skb, tmp) { 490fd558d18SJames Chapman if (time_after(jiffies, L2TP_SKB_CB(skb)->expires)) { 4917b7c0719STom Parkin atomic_long_inc(&session->stats.rx_seq_discards); 4927b7c0719STom Parkin atomic_long_inc(&session->stats.rx_errors); 493a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 494a4ca44faSJoe Perches "%s: oos pkt %u len %d discarded (too old), waiting for %u, reorder_q_len=%d\n", 495fd558d18SJames Chapman session->name, L2TP_SKB_CB(skb)->ns, 496fd558d18SJames Chapman L2TP_SKB_CB(skb)->length, session->nr, 497fd558d18SJames Chapman skb_queue_len(&session->reorder_q)); 49838d40b3fSJames Chapman session->reorder_skip = 1; 499fd558d18SJames Chapman __skb_unlink(skb, &session->reorder_q); 500fd558d18SJames Chapman kfree_skb(skb); 501fd558d18SJames Chapman if (session->deref) 502fd558d18SJames Chapman (*session->deref)(session); 503fd558d18SJames Chapman continue; 504fd558d18SJames Chapman } 505fd558d18SJames Chapman 506fd558d18SJames Chapman if (L2TP_SKB_CB(skb)->has_seq) { 50738d40b3fSJames Chapman if (session->reorder_skip) { 508a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 50938d40b3fSJames Chapman "%s: advancing nr to next pkt: %u -> %u", 51038d40b3fSJames Chapman session->name, session->nr, 51138d40b3fSJames Chapman L2TP_SKB_CB(skb)->ns); 51238d40b3fSJames Chapman session->reorder_skip = 0; 51338d40b3fSJames Chapman session->nr = L2TP_SKB_CB(skb)->ns; 51438d40b3fSJames Chapman } 515fd558d18SJames Chapman if (L2TP_SKB_CB(skb)->ns != session->nr) { 516a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 517a4ca44faSJoe Perches "%s: holding oos pkt %u len %d, waiting for %u, reorder_q_len=%d\n", 518fd558d18SJames Chapman session->name, L2TP_SKB_CB(skb)->ns, 519fd558d18SJames Chapman L2TP_SKB_CB(skb)->length, session->nr, 520fd558d18SJames Chapman skb_queue_len(&session->reorder_q)); 521fd558d18SJames Chapman goto out; 522fd558d18SJames Chapman } 523fd558d18SJames Chapman } 524fd558d18SJames Chapman __skb_unlink(skb, &session->reorder_q); 525fd558d18SJames Chapman 526fd558d18SJames Chapman /* Process the skb. We release the queue lock while we 527fd558d18SJames Chapman * do so to let other contexts process the queue. 528fd558d18SJames Chapman */ 529fd558d18SJames Chapman spin_unlock_bh(&session->reorder_q.lock); 530fd558d18SJames Chapman l2tp_recv_dequeue_skb(session, skb); 531e2e210c0SEric Dumazet goto start; 532fd558d18SJames Chapman } 533fd558d18SJames Chapman 534fd558d18SJames Chapman out: 535fd558d18SJames Chapman spin_unlock_bh(&session->reorder_q.lock); 536fd558d18SJames Chapman } 537fd558d18SJames Chapman 5388a1631d5SJames Chapman static int l2tp_seq_check_rx_window(struct l2tp_session *session, u32 nr) 5398a1631d5SJames Chapman { 5408a1631d5SJames Chapman u32 nws; 5418a1631d5SJames Chapman 5428a1631d5SJames Chapman if (nr >= session->nr) 5438a1631d5SJames Chapman nws = nr - session->nr; 5448a1631d5SJames Chapman else 5458a1631d5SJames Chapman nws = (session->nr_max + 1) - (session->nr - nr); 5468a1631d5SJames Chapman 5478a1631d5SJames Chapman return nws < session->nr_window_size; 5488a1631d5SJames Chapman } 5498a1631d5SJames Chapman 550b6dc01a4SJames Chapman /* If packet has sequence numbers, queue it if acceptable. Returns 0 if 551b6dc01a4SJames Chapman * acceptable, else non-zero. 552b6dc01a4SJames Chapman */ 553b6dc01a4SJames Chapman static int l2tp_recv_data_seq(struct l2tp_session *session, struct sk_buff *skb) 554b6dc01a4SJames Chapman { 5558a1631d5SJames Chapman if (!l2tp_seq_check_rx_window(session, L2TP_SKB_CB(skb)->ns)) { 5568a1631d5SJames Chapman /* Packet sequence number is outside allowed window. 5578a1631d5SJames Chapman * Discard it. 5588a1631d5SJames Chapman */ 5598a1631d5SJames Chapman l2tp_dbg(session, L2TP_MSG_SEQ, 5608a1631d5SJames Chapman "%s: pkt %u len %d discarded, outside window, nr=%u\n", 5618a1631d5SJames Chapman session->name, L2TP_SKB_CB(skb)->ns, 5628a1631d5SJames Chapman L2TP_SKB_CB(skb)->length, session->nr); 5638a1631d5SJames Chapman goto discard; 5648a1631d5SJames Chapman } 5658a1631d5SJames Chapman 566b6dc01a4SJames Chapman if (session->reorder_timeout != 0) { 567b6dc01a4SJames Chapman /* Packet reordering enabled. Add skb to session's 568b6dc01a4SJames Chapman * reorder queue, in order of ns. 569b6dc01a4SJames Chapman */ 570b6dc01a4SJames Chapman l2tp_recv_queue_skb(session, skb); 571a0dbd822SJames Chapman goto out; 572a0dbd822SJames Chapman } 573a0dbd822SJames Chapman 574a0dbd822SJames Chapman /* Packet reordering disabled. Discard out-of-sequence packets, while 575a0dbd822SJames Chapman * tracking the number if in-sequence packets after the first OOS packet 576a0dbd822SJames Chapman * is seen. After nr_oos_count_max in-sequence packets, reset the 577a0dbd822SJames Chapman * sequence number to re-enable packet reception. 578b6dc01a4SJames Chapman */ 579a0dbd822SJames Chapman if (L2TP_SKB_CB(skb)->ns == session->nr) { 580a0dbd822SJames Chapman skb_queue_tail(&session->reorder_q, skb); 581a0dbd822SJames Chapman } else { 582a0dbd822SJames Chapman u32 nr_oos = L2TP_SKB_CB(skb)->ns; 583a0dbd822SJames Chapman u32 nr_next = (session->nr_oos + 1) & session->nr_max; 584a0dbd822SJames Chapman 585a0dbd822SJames Chapman if (nr_oos == nr_next) 586a0dbd822SJames Chapman session->nr_oos_count++; 587a0dbd822SJames Chapman else 588a0dbd822SJames Chapman session->nr_oos_count = 0; 589a0dbd822SJames Chapman 590a0dbd822SJames Chapman session->nr_oos = nr_oos; 591a0dbd822SJames Chapman if (session->nr_oos_count > session->nr_oos_count_max) { 592a0dbd822SJames Chapman session->reorder_skip = 1; 593a0dbd822SJames Chapman l2tp_dbg(session, L2TP_MSG_SEQ, 594a0dbd822SJames Chapman "%s: %d oos packets received. Resetting sequence numbers\n", 595a0dbd822SJames Chapman session->name, session->nr_oos_count); 596a0dbd822SJames Chapman } 597a0dbd822SJames Chapman if (!session->reorder_skip) { 598b6dc01a4SJames Chapman atomic_long_inc(&session->stats.rx_seq_discards); 599b6dc01a4SJames Chapman l2tp_dbg(session, L2TP_MSG_SEQ, 600b6dc01a4SJames Chapman "%s: oos pkt %u len %d discarded, waiting for %u, reorder_q_len=%d\n", 601b6dc01a4SJames Chapman session->name, L2TP_SKB_CB(skb)->ns, 602b6dc01a4SJames Chapman L2TP_SKB_CB(skb)->length, session->nr, 603b6dc01a4SJames Chapman skb_queue_len(&session->reorder_q)); 604b6dc01a4SJames Chapman goto discard; 605b6dc01a4SJames Chapman } 606b6dc01a4SJames Chapman skb_queue_tail(&session->reorder_q, skb); 607b6dc01a4SJames Chapman } 608b6dc01a4SJames Chapman 609a0dbd822SJames Chapman out: 610b6dc01a4SJames Chapman return 0; 611b6dc01a4SJames Chapman 612b6dc01a4SJames Chapman discard: 613b6dc01a4SJames Chapman return 1; 614b6dc01a4SJames Chapman } 615b6dc01a4SJames Chapman 616f7faffa3SJames Chapman /* Do receive processing of L2TP data frames. We handle both L2TPv2 617f7faffa3SJames Chapman * and L2TPv3 data frames here. 618f7faffa3SJames Chapman * 619f7faffa3SJames Chapman * L2TPv2 Data Message Header 620f7faffa3SJames Chapman * 621f7faffa3SJames Chapman * 0 1 2 3 622f7faffa3SJames Chapman * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 623f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 624f7faffa3SJames Chapman * |T|L|x|x|S|x|O|P|x|x|x|x| Ver | Length (opt) | 625f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 626f7faffa3SJames Chapman * | Tunnel ID | Session ID | 627f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 628f7faffa3SJames Chapman * | Ns (opt) | Nr (opt) | 629f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 630f7faffa3SJames Chapman * | Offset Size (opt) | Offset pad... (opt) 631f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 632f7faffa3SJames Chapman * 633f7faffa3SJames Chapman * Data frames are marked by T=0. All other fields are the same as 634f7faffa3SJames Chapman * those in L2TP control frames. 635f7faffa3SJames Chapman * 636f7faffa3SJames Chapman * L2TPv3 Data Message Header 637f7faffa3SJames Chapman * 638f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 639f7faffa3SJames Chapman * | L2TP Session Header | 640f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 641f7faffa3SJames Chapman * | L2-Specific Sublayer | 642f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 643f7faffa3SJames Chapman * | Tunnel Payload ... 644f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 645f7faffa3SJames Chapman * 646f7faffa3SJames Chapman * L2TPv3 Session Header Over IP 647f7faffa3SJames Chapman * 648f7faffa3SJames Chapman * 0 1 2 3 649f7faffa3SJames Chapman * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 650f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 651f7faffa3SJames Chapman * | Session ID | 652f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 653f7faffa3SJames Chapman * | Cookie (optional, maximum 64 bits)... 654f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 655f7faffa3SJames Chapman * | 656f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 657f7faffa3SJames Chapman * 658f7faffa3SJames Chapman * L2TPv3 L2-Specific Sublayer Format 659f7faffa3SJames Chapman * 660f7faffa3SJames Chapman * 0 1 2 3 661f7faffa3SJames Chapman * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 662f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 663f7faffa3SJames Chapman * |x|S|x|x|x|x|x|x| Sequence Number | 664f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 665f7faffa3SJames Chapman * 666f7faffa3SJames Chapman * Cookie value, sublayer format and offset (pad) are negotiated with 667f7faffa3SJames Chapman * the peer when the session is set up. Unlike L2TPv2, we do not need 668f7faffa3SJames Chapman * to parse the packet header to determine if optional fields are 669f7faffa3SJames Chapman * present. 670f7faffa3SJames Chapman * 671f7faffa3SJames Chapman * Caller must already have parsed the frame and determined that it is 672f7faffa3SJames Chapman * a data (not control) frame before coming here. Fields up to the 673f7faffa3SJames Chapman * session-id have already been parsed and ptr points to the data 674f7faffa3SJames Chapman * after the session-id. 67561b9a047SGuillaume Nault * 67661b9a047SGuillaume Nault * session->ref() must have been called prior to l2tp_recv_common(). 67761b9a047SGuillaume Nault * session->deref() will be called automatically after skb is processed. 678f7faffa3SJames Chapman */ 679f7faffa3SJames Chapman void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, 680f7faffa3SJames Chapman unsigned char *ptr, unsigned char *optr, u16 hdrflags, 681f7faffa3SJames Chapman int length, int (*payload_hook)(struct sk_buff *skb)) 682f7faffa3SJames Chapman { 683f7faffa3SJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 684f7faffa3SJames Chapman int offset; 685f7faffa3SJames Chapman u32 ns, nr; 686f7faffa3SJames Chapman 687f7faffa3SJames Chapman /* Parse and check optional cookie */ 688f7faffa3SJames Chapman if (session->peer_cookie_len > 0) { 689f7faffa3SJames Chapman if (memcmp(ptr, &session->peer_cookie[0], session->peer_cookie_len)) { 690a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_DATA, 691f7faffa3SJames Chapman "%s: cookie mismatch (%u/%u). Discarding.\n", 692a4ca44faSJoe Perches tunnel->name, tunnel->tunnel_id, 693a4ca44faSJoe Perches session->session_id); 6947b7c0719STom Parkin atomic_long_inc(&session->stats.rx_cookie_discards); 695f7faffa3SJames Chapman goto discard; 696f7faffa3SJames Chapman } 697f7faffa3SJames Chapman ptr += session->peer_cookie_len; 698f7faffa3SJames Chapman } 699f7faffa3SJames Chapman 700f7faffa3SJames Chapman /* Handle the optional sequence numbers. Sequence numbers are 701f7faffa3SJames Chapman * in different places for L2TPv2 and L2TPv3. 702f7faffa3SJames Chapman * 703f7faffa3SJames Chapman * If we are the LAC, enable/disable sequence numbers under 704f7faffa3SJames Chapman * the control of the LNS. If no sequence numbers present but 705f7faffa3SJames Chapman * we were expecting them, discard frame. 706f7faffa3SJames Chapman */ 707f7faffa3SJames Chapman ns = nr = 0; 708f7faffa3SJames Chapman L2TP_SKB_CB(skb)->has_seq = 0; 709f7faffa3SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) { 710f7faffa3SJames Chapman if (hdrflags & L2TP_HDRFLAG_S) { 711f7faffa3SJames Chapman ns = ntohs(*(__be16 *) ptr); 712f7faffa3SJames Chapman ptr += 2; 713f7faffa3SJames Chapman nr = ntohs(*(__be16 *) ptr); 714f7faffa3SJames Chapman ptr += 2; 715f7faffa3SJames Chapman 716f7faffa3SJames Chapman /* Store L2TP info in the skb */ 717f7faffa3SJames Chapman L2TP_SKB_CB(skb)->ns = ns; 718f7faffa3SJames Chapman L2TP_SKB_CB(skb)->has_seq = 1; 719f7faffa3SJames Chapman 720a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 721f7faffa3SJames Chapman "%s: recv data ns=%u, nr=%u, session nr=%u\n", 722f7faffa3SJames Chapman session->name, ns, nr, session->nr); 723f7faffa3SJames Chapman } 724f7faffa3SJames Chapman } else if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { 725f7faffa3SJames Chapman u32 l2h = ntohl(*(__be32 *) ptr); 726f7faffa3SJames Chapman 727f7faffa3SJames Chapman if (l2h & 0x40000000) { 728f7faffa3SJames Chapman ns = l2h & 0x00ffffff; 729f7faffa3SJames Chapman 730f7faffa3SJames Chapman /* Store L2TP info in the skb */ 731f7faffa3SJames Chapman L2TP_SKB_CB(skb)->ns = ns; 732f7faffa3SJames Chapman L2TP_SKB_CB(skb)->has_seq = 1; 733f7faffa3SJames Chapman 734a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 735f7faffa3SJames Chapman "%s: recv data ns=%u, session nr=%u\n", 736f7faffa3SJames Chapman session->name, ns, session->nr); 737f7faffa3SJames Chapman } 738f7faffa3SJames Chapman } 739f7faffa3SJames Chapman 740f7faffa3SJames Chapman /* Advance past L2-specific header, if present */ 741f7faffa3SJames Chapman ptr += session->l2specific_len; 742f7faffa3SJames Chapman 743f7faffa3SJames Chapman if (L2TP_SKB_CB(skb)->has_seq) { 744f7faffa3SJames Chapman /* Received a packet with sequence numbers. If we're the LNS, 745f7faffa3SJames Chapman * check if we sre sending sequence numbers and if not, 746f7faffa3SJames Chapman * configure it so. 747f7faffa3SJames Chapman */ 748f7faffa3SJames Chapman if ((!session->lns_mode) && (!session->send_seq)) { 749a4ca44faSJoe Perches l2tp_info(session, L2TP_MSG_SEQ, 750f7faffa3SJames Chapman "%s: requested to enable seq numbers by LNS\n", 751f7faffa3SJames Chapman session->name); 7523f9b9770SAsbjørn Sloth Tønnesen session->send_seq = 1; 753f7faffa3SJames Chapman l2tp_session_set_header_len(session, tunnel->version); 754f7faffa3SJames Chapman } 755f7faffa3SJames Chapman } else { 756f7faffa3SJames Chapman /* No sequence numbers. 757f7faffa3SJames Chapman * If user has configured mandatory sequence numbers, discard. 758f7faffa3SJames Chapman */ 759f7faffa3SJames Chapman if (session->recv_seq) { 760a4ca44faSJoe Perches l2tp_warn(session, L2TP_MSG_SEQ, 761a4ca44faSJoe Perches "%s: recv data has no seq numbers when required. Discarding.\n", 762a4ca44faSJoe Perches session->name); 7637b7c0719STom Parkin atomic_long_inc(&session->stats.rx_seq_discards); 764f7faffa3SJames Chapman goto discard; 765f7faffa3SJames Chapman } 766f7faffa3SJames Chapman 767f7faffa3SJames Chapman /* If we're the LAC and we're sending sequence numbers, the 768f7faffa3SJames Chapman * LNS has requested that we no longer send sequence numbers. 769f7faffa3SJames Chapman * If we're the LNS and we're sending sequence numbers, the 770f7faffa3SJames Chapman * LAC is broken. Discard the frame. 771f7faffa3SJames Chapman */ 772f7faffa3SJames Chapman if ((!session->lns_mode) && (session->send_seq)) { 773a4ca44faSJoe Perches l2tp_info(session, L2TP_MSG_SEQ, 774f7faffa3SJames Chapman "%s: requested to disable seq numbers by LNS\n", 775f7faffa3SJames Chapman session->name); 776f7faffa3SJames Chapman session->send_seq = 0; 777f7faffa3SJames Chapman l2tp_session_set_header_len(session, tunnel->version); 778f7faffa3SJames Chapman } else if (session->send_seq) { 779a4ca44faSJoe Perches l2tp_warn(session, L2TP_MSG_SEQ, 780a4ca44faSJoe Perches "%s: recv data has no seq numbers when required. Discarding.\n", 781a4ca44faSJoe Perches session->name); 7827b7c0719STom Parkin atomic_long_inc(&session->stats.rx_seq_discards); 783f7faffa3SJames Chapman goto discard; 784f7faffa3SJames Chapman } 785f7faffa3SJames Chapman } 786f7faffa3SJames Chapman 787f7faffa3SJames Chapman /* Session data offset is handled differently for L2TPv2 and 788f7faffa3SJames Chapman * L2TPv3. For L2TPv2, there is an optional 16-bit value in 789f7faffa3SJames Chapman * the header. For L2TPv3, the offset is negotiated using AVPs 790f7faffa3SJames Chapman * in the session setup control protocol. 791f7faffa3SJames Chapman */ 792f7faffa3SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) { 793f7faffa3SJames Chapman /* If offset bit set, skip it. */ 794f7faffa3SJames Chapman if (hdrflags & L2TP_HDRFLAG_O) { 795f7faffa3SJames Chapman offset = ntohs(*(__be16 *)ptr); 796f7faffa3SJames Chapman ptr += 2 + offset; 797f7faffa3SJames Chapman } 798f7faffa3SJames Chapman } else 799f7faffa3SJames Chapman ptr += session->offset; 800f7faffa3SJames Chapman 801f7faffa3SJames Chapman offset = ptr - optr; 802f7faffa3SJames Chapman if (!pskb_may_pull(skb, offset)) 803f7faffa3SJames Chapman goto discard; 804f7faffa3SJames Chapman 805f7faffa3SJames Chapman __skb_pull(skb, offset); 806f7faffa3SJames Chapman 807f7faffa3SJames Chapman /* If caller wants to process the payload before we queue the 808f7faffa3SJames Chapman * packet, do so now. 809f7faffa3SJames Chapman */ 810f7faffa3SJames Chapman if (payload_hook) 811f7faffa3SJames Chapman if ((*payload_hook)(skb)) 812f7faffa3SJames Chapman goto discard; 813f7faffa3SJames Chapman 814f7faffa3SJames Chapman /* Prepare skb for adding to the session's reorder_q. Hold 815f7faffa3SJames Chapman * packets for max reorder_timeout or 1 second if not 816f7faffa3SJames Chapman * reordering. 817f7faffa3SJames Chapman */ 818f7faffa3SJames Chapman L2TP_SKB_CB(skb)->length = length; 819f7faffa3SJames Chapman L2TP_SKB_CB(skb)->expires = jiffies + 820f7faffa3SJames Chapman (session->reorder_timeout ? session->reorder_timeout : HZ); 821f7faffa3SJames Chapman 822f7faffa3SJames Chapman /* Add packet to the session's receive queue. Reordering is done here, if 823f7faffa3SJames Chapman * enabled. Saved L2TP protocol info is stored in skb->sb[]. 824f7faffa3SJames Chapman */ 825f7faffa3SJames Chapman if (L2TP_SKB_CB(skb)->has_seq) { 826b6dc01a4SJames Chapman if (l2tp_recv_data_seq(session, skb)) 827f7faffa3SJames Chapman goto discard; 828f7faffa3SJames Chapman } else { 829f7faffa3SJames Chapman /* No sequence numbers. Add the skb to the tail of the 830f7faffa3SJames Chapman * reorder queue. This ensures that it will be 831f7faffa3SJames Chapman * delivered after all previous sequenced skbs. 832f7faffa3SJames Chapman */ 833f7faffa3SJames Chapman skb_queue_tail(&session->reorder_q, skb); 834f7faffa3SJames Chapman } 835f7faffa3SJames Chapman 836f7faffa3SJames Chapman /* Try to dequeue as many skbs from reorder_q as we can. */ 837f7faffa3SJames Chapman l2tp_recv_dequeue(session); 838f7faffa3SJames Chapman 839f7faffa3SJames Chapman return; 840f7faffa3SJames Chapman 841f7faffa3SJames Chapman discard: 8427b7c0719STom Parkin atomic_long_inc(&session->stats.rx_errors); 843f7faffa3SJames Chapman kfree_skb(skb); 844f7faffa3SJames Chapman 845f7faffa3SJames Chapman if (session->deref) 846f7faffa3SJames Chapman (*session->deref)(session); 847f7faffa3SJames Chapman } 848f7faffa3SJames Chapman EXPORT_SYMBOL(l2tp_recv_common); 849f7faffa3SJames Chapman 85048f72f92STom Parkin /* Drop skbs from the session's reorder_q 85148f72f92STom Parkin */ 85248f72f92STom Parkin int l2tp_session_queue_purge(struct l2tp_session *session) 85348f72f92STom Parkin { 85448f72f92STom Parkin struct sk_buff *skb = NULL; 85548f72f92STom Parkin BUG_ON(!session); 85648f72f92STom Parkin BUG_ON(session->magic != L2TP_SESSION_MAGIC); 85748f72f92STom Parkin while ((skb = skb_dequeue(&session->reorder_q))) { 85848f72f92STom Parkin atomic_long_inc(&session->stats.rx_errors); 85948f72f92STom Parkin kfree_skb(skb); 86048f72f92STom Parkin if (session->deref) 86148f72f92STom Parkin (*session->deref)(session); 86248f72f92STom Parkin } 86348f72f92STom Parkin return 0; 86448f72f92STom Parkin } 86548f72f92STom Parkin EXPORT_SYMBOL_GPL(l2tp_session_queue_purge); 86648f72f92STom Parkin 867fd558d18SJames Chapman /* Internal UDP receive frame. Do the real work of receiving an L2TP data frame 868fd558d18SJames Chapman * here. The skb is not on a list when we get here. 869fd558d18SJames Chapman * Returns 0 if the packet was a data packet and was successfully passed on. 870fd558d18SJames Chapman * Returns 1 if the packet was not a good data packet and could not be 871fd558d18SJames Chapman * forwarded. All such packets are passed up to userspace to deal with. 872fd558d18SJames Chapman */ 873fc130840Sstephen hemminger static int l2tp_udp_recv_core(struct l2tp_tunnel *tunnel, struct sk_buff *skb, 874fd558d18SJames Chapman int (*payload_hook)(struct sk_buff *skb)) 875fd558d18SJames Chapman { 876fd558d18SJames Chapman struct l2tp_session *session = NULL; 877fd558d18SJames Chapman unsigned char *ptr, *optr; 878fd558d18SJames Chapman u16 hdrflags; 879fd558d18SJames Chapman u32 tunnel_id, session_id; 880fd558d18SJames Chapman u16 version; 881f7faffa3SJames Chapman int length; 882fd558d18SJames Chapman 88358d6085cSTom Herbert /* UDP has verifed checksum */ 884fd558d18SJames Chapman 885fd558d18SJames Chapman /* UDP always verifies the packet length. */ 886fd558d18SJames Chapman __skb_pull(skb, sizeof(struct udphdr)); 887fd558d18SJames Chapman 888fd558d18SJames Chapman /* Short packet? */ 889fd558d18SJames Chapman if (!pskb_may_pull(skb, L2TP_HDR_SIZE_SEQ)) { 890a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_DATA, 891a4ca44faSJoe Perches "%s: recv short packet (len=%d)\n", 892a4ca44faSJoe Perches tunnel->name, skb->len); 893fd558d18SJames Chapman goto error; 894fd558d18SJames Chapman } 895fd558d18SJames Chapman 896fd558d18SJames Chapman /* Trace packet contents, if enabled */ 897fd558d18SJames Chapman if (tunnel->debug & L2TP_MSG_DATA) { 898fd558d18SJames Chapman length = min(32u, skb->len); 899fd558d18SJames Chapman if (!pskb_may_pull(skb, length)) 900fd558d18SJames Chapman goto error; 901fd558d18SJames Chapman 902a4ca44faSJoe Perches pr_debug("%s: recv\n", tunnel->name); 903a4ca44faSJoe Perches print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, skb->data, length); 904fd558d18SJames Chapman } 905fd558d18SJames Chapman 906e50e705cSEric Dumazet /* Point to L2TP header */ 907e50e705cSEric Dumazet optr = ptr = skb->data; 908e50e705cSEric Dumazet 909fd558d18SJames Chapman /* Get L2TP header flags */ 910fd558d18SJames Chapman hdrflags = ntohs(*(__be16 *) ptr); 911fd558d18SJames Chapman 912fd558d18SJames Chapman /* Check protocol version */ 913fd558d18SJames Chapman version = hdrflags & L2TP_HDR_VER_MASK; 914fd558d18SJames Chapman if (version != tunnel->version) { 915a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_DATA, 916fd558d18SJames Chapman "%s: recv protocol version mismatch: got %d expected %d\n", 917fd558d18SJames Chapman tunnel->name, version, tunnel->version); 918fd558d18SJames Chapman goto error; 919fd558d18SJames Chapman } 920fd558d18SJames Chapman 921fd558d18SJames Chapman /* Get length of L2TP packet */ 922fd558d18SJames Chapman length = skb->len; 923fd558d18SJames Chapman 924fd558d18SJames Chapman /* If type is control packet, it is handled by userspace. */ 925fd558d18SJames Chapman if (hdrflags & L2TP_HDRFLAG_T) { 926a4ca44faSJoe Perches l2tp_dbg(tunnel, L2TP_MSG_DATA, 927a4ca44faSJoe Perches "%s: recv control packet, len=%d\n", 928a4ca44faSJoe Perches tunnel->name, length); 929fd558d18SJames Chapman goto error; 930fd558d18SJames Chapman } 931fd558d18SJames Chapman 932fd558d18SJames Chapman /* Skip flags */ 933fd558d18SJames Chapman ptr += 2; 934fd558d18SJames Chapman 935f7faffa3SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) { 936fd558d18SJames Chapman /* If length is present, skip it */ 937fd558d18SJames Chapman if (hdrflags & L2TP_HDRFLAG_L) 938fd558d18SJames Chapman ptr += 2; 939fd558d18SJames Chapman 940fd558d18SJames Chapman /* Extract tunnel and session ID */ 941fd558d18SJames Chapman tunnel_id = ntohs(*(__be16 *) ptr); 942fd558d18SJames Chapman ptr += 2; 943fd558d18SJames Chapman session_id = ntohs(*(__be16 *) ptr); 944fd558d18SJames Chapman ptr += 2; 945f7faffa3SJames Chapman } else { 946f7faffa3SJames Chapman ptr += 2; /* skip reserved bits */ 947f7faffa3SJames Chapman tunnel_id = tunnel->tunnel_id; 948f7faffa3SJames Chapman session_id = ntohl(*(__be32 *) ptr); 949f7faffa3SJames Chapman ptr += 4; 950f7faffa3SJames Chapman } 951fd558d18SJames Chapman 952fd558d18SJames Chapman /* Find the session context */ 95361b9a047SGuillaume Nault session = l2tp_session_get(tunnel->l2tp_net, tunnel, session_id, true); 954309795f4SJames Chapman if (!session || !session->recv_skb) { 95561b9a047SGuillaume Nault if (session) { 95661b9a047SGuillaume Nault if (session->deref) 95761b9a047SGuillaume Nault session->deref(session); 95861b9a047SGuillaume Nault l2tp_session_dec_refcount(session); 95961b9a047SGuillaume Nault } 96061b9a047SGuillaume Nault 961fd558d18SJames Chapman /* Not found? Pass to userspace to deal with */ 962a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_DATA, 963f7faffa3SJames Chapman "%s: no session found (%u/%u). Passing up.\n", 964fd558d18SJames Chapman tunnel->name, tunnel_id, session_id); 965fd558d18SJames Chapman goto error; 966fd558d18SJames Chapman } 967fd558d18SJames Chapman 968f7faffa3SJames Chapman l2tp_recv_common(session, skb, ptr, optr, hdrflags, length, payload_hook); 96961b9a047SGuillaume Nault l2tp_session_dec_refcount(session); 970fd558d18SJames Chapman 971fd558d18SJames Chapman return 0; 972fd558d18SJames Chapman 973fd558d18SJames Chapman error: 974fd558d18SJames Chapman /* Put UDP header back */ 975fd558d18SJames Chapman __skb_push(skb, sizeof(struct udphdr)); 976fd558d18SJames Chapman 977fd558d18SJames Chapman return 1; 978fd558d18SJames Chapman } 979fd558d18SJames Chapman 980fd558d18SJames Chapman /* UDP encapsulation receive handler. See net/ipv4/udp.c. 981fd558d18SJames Chapman * Return codes: 982fd558d18SJames Chapman * 0 : success. 983fd558d18SJames Chapman * <0: error 984fd558d18SJames Chapman * >0: skb should be passed up to userspace as UDP. 985fd558d18SJames Chapman */ 986fd558d18SJames Chapman int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) 987fd558d18SJames Chapman { 988fd558d18SJames Chapman struct l2tp_tunnel *tunnel; 989fd558d18SJames Chapman 990fd558d18SJames Chapman tunnel = l2tp_sock_to_tunnel(sk); 991fd558d18SJames Chapman if (tunnel == NULL) 992fd558d18SJames Chapman goto pass_up; 993fd558d18SJames Chapman 994a4ca44faSJoe Perches l2tp_dbg(tunnel, L2TP_MSG_DATA, "%s: received %d bytes\n", 995a4ca44faSJoe Perches tunnel->name, skb->len); 996fd558d18SJames Chapman 997fd558d18SJames Chapman if (l2tp_udp_recv_core(tunnel, skb, tunnel->recv_payload_hook)) 998fd558d18SJames Chapman goto pass_up_put; 999fd558d18SJames Chapman 1000fd558d18SJames Chapman sock_put(sk); 1001fd558d18SJames Chapman return 0; 1002fd558d18SJames Chapman 1003fd558d18SJames Chapman pass_up_put: 1004fd558d18SJames Chapman sock_put(sk); 1005fd558d18SJames Chapman pass_up: 1006fd558d18SJames Chapman return 1; 1007fd558d18SJames Chapman } 1008fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_udp_encap_recv); 1009fd558d18SJames Chapman 1010fd558d18SJames Chapman /************************************************************************ 1011fd558d18SJames Chapman * Transmit handling 1012fd558d18SJames Chapman ***********************************************************************/ 1013fd558d18SJames Chapman 1014fd558d18SJames Chapman /* Build an L2TP header for the session into the buffer provided. 1015fd558d18SJames Chapman */ 1016f7faffa3SJames Chapman static int l2tp_build_l2tpv2_header(struct l2tp_session *session, void *buf) 1017fd558d18SJames Chapman { 1018f7faffa3SJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 1019fd558d18SJames Chapman __be16 *bufp = buf; 1020f7faffa3SJames Chapman __be16 *optr = buf; 1021fd558d18SJames Chapman u16 flags = L2TP_HDR_VER_2; 1022fd558d18SJames Chapman u32 tunnel_id = tunnel->peer_tunnel_id; 1023fd558d18SJames Chapman u32 session_id = session->peer_session_id; 1024fd558d18SJames Chapman 1025fd558d18SJames Chapman if (session->send_seq) 1026fd558d18SJames Chapman flags |= L2TP_HDRFLAG_S; 1027fd558d18SJames Chapman 1028fd558d18SJames Chapman /* Setup L2TP header. */ 1029fd558d18SJames Chapman *bufp++ = htons(flags); 1030fd558d18SJames Chapman *bufp++ = htons(tunnel_id); 1031fd558d18SJames Chapman *bufp++ = htons(session_id); 1032fd558d18SJames Chapman if (session->send_seq) { 1033fd558d18SJames Chapman *bufp++ = htons(session->ns); 1034fd558d18SJames Chapman *bufp++ = 0; 1035fd558d18SJames Chapman session->ns++; 1036f7faffa3SJames Chapman session->ns &= 0xffff; 1037a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, "%s: updated ns to %u\n", 1038a4ca44faSJoe Perches session->name, session->ns); 1039fd558d18SJames Chapman } 1040fd558d18SJames Chapman 1041f7faffa3SJames Chapman return bufp - optr; 1042f7faffa3SJames Chapman } 1043f7faffa3SJames Chapman 1044f7faffa3SJames Chapman static int l2tp_build_l2tpv3_header(struct l2tp_session *session, void *buf) 1045fd558d18SJames Chapman { 10460d76751fSJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 1047f7faffa3SJames Chapman char *bufp = buf; 1048f7faffa3SJames Chapman char *optr = bufp; 1049fd558d18SJames Chapman 10500d76751fSJames Chapman /* Setup L2TP header. The header differs slightly for UDP and 10510d76751fSJames Chapman * IP encapsulations. For UDP, there is 4 bytes of flags. 10520d76751fSJames Chapman */ 10530d76751fSJames Chapman if (tunnel->encap == L2TP_ENCAPTYPE_UDP) { 10540d76751fSJames Chapman u16 flags = L2TP_HDR_VER_3; 1055f7faffa3SJames Chapman *((__be16 *) bufp) = htons(flags); 1056f7faffa3SJames Chapman bufp += 2; 1057f7faffa3SJames Chapman *((__be16 *) bufp) = 0; 1058f7faffa3SJames Chapman bufp += 2; 10590d76751fSJames Chapman } 10600d76751fSJames Chapman 1061f7faffa3SJames Chapman *((__be32 *) bufp) = htonl(session->peer_session_id); 1062f7faffa3SJames Chapman bufp += 4; 1063f7faffa3SJames Chapman if (session->cookie_len) { 1064f7faffa3SJames Chapman memcpy(bufp, &session->cookie[0], session->cookie_len); 1065f7faffa3SJames Chapman bufp += session->cookie_len; 1066fd558d18SJames Chapman } 1067f7faffa3SJames Chapman if (session->l2specific_len) { 1068f7faffa3SJames Chapman if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { 1069f7faffa3SJames Chapman u32 l2h = 0; 1070f7faffa3SJames Chapman if (session->send_seq) { 1071f7faffa3SJames Chapman l2h = 0x40000000 | session->ns; 1072f7faffa3SJames Chapman session->ns++; 1073f7faffa3SJames Chapman session->ns &= 0xffffff; 1074a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 1075a4ca44faSJoe Perches "%s: updated ns to %u\n", 1076a4ca44faSJoe Perches session->name, session->ns); 1077f7faffa3SJames Chapman } 1078f7faffa3SJames Chapman 1079f7faffa3SJames Chapman *((__be32 *) bufp) = htonl(l2h); 1080f7faffa3SJames Chapman } 1081f7faffa3SJames Chapman bufp += session->l2specific_len; 1082f7faffa3SJames Chapman } 1083f7faffa3SJames Chapman if (session->offset) 1084f7faffa3SJames Chapman bufp += session->offset; 1085f7faffa3SJames Chapman 1086f7faffa3SJames Chapman return bufp - optr; 1087f7faffa3SJames Chapman } 1088fd558d18SJames Chapman 1089fc130840Sstephen hemminger static int l2tp_xmit_core(struct l2tp_session *session, struct sk_buff *skb, 1090d9d8da80SDavid S. Miller struct flowi *fl, size_t data_len) 1091fd558d18SJames Chapman { 1092fd558d18SJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 1093fd558d18SJames Chapman unsigned int len = skb->len; 1094fd558d18SJames Chapman int error; 1095fd558d18SJames Chapman 1096fd558d18SJames Chapman /* Debug */ 1097fd558d18SJames Chapman if (session->send_seq) 10985b5e0928SAlexey Dobriyan l2tp_dbg(session, L2TP_MSG_DATA, "%s: send %zd bytes, ns=%u\n", 1099a4ca44faSJoe Perches session->name, data_len, session->ns - 1); 1100fd558d18SJames Chapman else 11015b5e0928SAlexey Dobriyan l2tp_dbg(session, L2TP_MSG_DATA, "%s: send %zd bytes\n", 1102a4ca44faSJoe Perches session->name, data_len); 1103fd558d18SJames Chapman 1104fd558d18SJames Chapman if (session->debug & L2TP_MSG_DATA) { 11050d76751fSJames Chapman int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; 11060d76751fSJames Chapman unsigned char *datap = skb->data + uhlen; 1107fd558d18SJames Chapman 1108a4ca44faSJoe Perches pr_debug("%s: xmit\n", session->name); 1109a4ca44faSJoe Perches print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, 1110a4ca44faSJoe Perches datap, min_t(size_t, 32, len - uhlen)); 1111fd558d18SJames Chapman } 1112fd558d18SJames Chapman 1113fd558d18SJames Chapman /* Queue the packet to IP for output */ 111460ff7467SWANG Cong skb->ignore_df = 1; 1115d2cf3361SBenjamin LaHaise #if IS_ENABLED(CONFIG_IPV6) 1116746e3499SEric Dumazet if (tunnel->sock->sk_family == PF_INET6 && !tunnel->v4mapped) 1117b0270e91SEric Dumazet error = inet6_csk_xmit(tunnel->sock, skb, NULL); 1118d2cf3361SBenjamin LaHaise else 1119d2cf3361SBenjamin LaHaise #endif 1120b0270e91SEric Dumazet error = ip_queue_xmit(tunnel->sock, skb, fl); 1121fd558d18SJames Chapman 1122fd558d18SJames Chapman /* Update stats */ 1123fd558d18SJames Chapman if (error >= 0) { 11247b7c0719STom Parkin atomic_long_inc(&tunnel->stats.tx_packets); 11257b7c0719STom Parkin atomic_long_add(len, &tunnel->stats.tx_bytes); 11267b7c0719STom Parkin atomic_long_inc(&session->stats.tx_packets); 11277b7c0719STom Parkin atomic_long_add(len, &session->stats.tx_bytes); 1128fd558d18SJames Chapman } else { 11297b7c0719STom Parkin atomic_long_inc(&tunnel->stats.tx_errors); 11307b7c0719STom Parkin atomic_long_inc(&session->stats.tx_errors); 1131fd558d18SJames Chapman } 1132fd558d18SJames Chapman 1133fd558d18SJames Chapman return 0; 1134fd558d18SJames Chapman } 1135fd558d18SJames Chapman 1136fd558d18SJames Chapman /* If caller requires the skb to have a ppp header, the header must be 1137fd558d18SJames Chapman * inserted in the skb data before calling this function. 1138fd558d18SJames Chapman */ 1139fd558d18SJames Chapman int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len) 1140fd558d18SJames Chapman { 1141fd558d18SJames Chapman int data_len = skb->len; 11420d76751fSJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 11430d76751fSJames Chapman struct sock *sk = tunnel->sock; 1144d9d8da80SDavid S. Miller struct flowi *fl; 1145fd558d18SJames Chapman struct udphdr *uh; 1146fd558d18SJames Chapman struct inet_sock *inet; 1147fd558d18SJames Chapman int headroom; 11480d76751fSJames Chapman int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; 11490d76751fSJames Chapman int udp_len; 1150b8c84307SEric Dumazet int ret = NET_XMIT_SUCCESS; 1151fd558d18SJames Chapman 1152fd558d18SJames Chapman /* Check that there's enough headroom in the skb to insert IP, 1153fd558d18SJames Chapman * UDP and L2TP headers. If not enough, expand it to 1154fd558d18SJames Chapman * make room. Adjust truesize. 1155fd558d18SJames Chapman */ 1156fd558d18SJames Chapman headroom = NET_SKB_PAD + sizeof(struct iphdr) + 11570d76751fSJames Chapman uhlen + hdr_len; 1158835acf5dSEric Dumazet if (skb_cow_head(skb, headroom)) { 1159b8c84307SEric Dumazet kfree_skb(skb); 1160b8c84307SEric Dumazet return NET_XMIT_DROP; 1161835acf5dSEric Dumazet } 1162fd558d18SJames Chapman 1163fd558d18SJames Chapman /* Setup L2TP header */ 1164f7faffa3SJames Chapman session->build_header(session, __skb_push(skb, hdr_len)); 1165fd558d18SJames Chapman 11660d76751fSJames Chapman /* Reset skb netfilter state */ 1167fd558d18SJames Chapman memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 1168fd558d18SJames Chapman IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | 1169fd558d18SJames Chapman IPSKB_REROUTED); 1170fd558d18SJames Chapman nf_reset(skb); 1171fd558d18SJames Chapman 11726af88da1SDavid S. Miller bh_lock_sock(sk); 11736af88da1SDavid S. Miller if (sock_owned_by_user(sk)) { 1174b8c84307SEric Dumazet kfree_skb(skb); 1175b8c84307SEric Dumazet ret = NET_XMIT_DROP; 11766af88da1SDavid S. Miller goto out_unlock; 11776af88da1SDavid S. Miller } 11786af88da1SDavid S. Miller 1179fd558d18SJames Chapman /* Get routing info from the tunnel socket */ 1180fd558d18SJames Chapman skb_dst_drop(skb); 118171b1391aSFlorian Westphal skb_dst_set(skb, dst_clone(__sk_dst_check(sk, 0))); 11820d76751fSJames Chapman 1183d9d8da80SDavid S. Miller inet = inet_sk(sk); 1184d9d8da80SDavid S. Miller fl = &inet->cork.fl; 11850d76751fSJames Chapman switch (tunnel->encap) { 11860d76751fSJames Chapman case L2TP_ENCAPTYPE_UDP: 11870d76751fSJames Chapman /* Setup UDP header */ 11880d76751fSJames Chapman __skb_push(skb, sizeof(*uh)); 11890d76751fSJames Chapman skb_reset_transport_header(skb); 11900d76751fSJames Chapman uh = udp_hdr(skb); 11910d76751fSJames Chapman uh->source = inet->inet_sport; 11920d76751fSJames Chapman uh->dest = inet->inet_dport; 11930d76751fSJames Chapman udp_len = uhlen + hdr_len + data_len; 11940d76751fSJames Chapman uh->len = htons(udp_len); 1195fd558d18SJames Chapman 1196fd558d18SJames Chapman /* Calculate UDP checksum if configured to do so */ 1197d2cf3361SBenjamin LaHaise #if IS_ENABLED(CONFIG_IPV6) 1198e18503f4SFrançois Cachereul if (sk->sk_family == PF_INET6 && !tunnel->v4mapped) 119977157e19STom Herbert udp6_set_csum(udp_get_no_check6_tx(sk), 120077157e19STom Herbert skb, &inet6_sk(sk)->saddr, 120177157e19STom Herbert &sk->sk_v6_daddr, udp_len); 1202d2cf3361SBenjamin LaHaise else 1203d2cf3361SBenjamin LaHaise #endif 120477157e19STom Herbert udp_set_csum(sk->sk_no_check_tx, skb, inet->inet_saddr, 120577157e19STom Herbert inet->inet_daddr, udp_len); 12060d76751fSJames Chapman break; 12070d76751fSJames Chapman 12080d76751fSJames Chapman case L2TP_ENCAPTYPE_IP: 12090d76751fSJames Chapman break; 12100d76751fSJames Chapman } 12110d76751fSJames Chapman 1212d9d8da80SDavid S. Miller l2tp_xmit_core(session, skb, fl, data_len); 12136af88da1SDavid S. Miller out_unlock: 12146af88da1SDavid S. Miller bh_unlock_sock(sk); 1215fd558d18SJames Chapman 1216b8c84307SEric Dumazet return ret; 1217fd558d18SJames Chapman } 1218fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_xmit_skb); 1219fd558d18SJames Chapman 1220fd558d18SJames Chapman /***************************************************************************** 1221fd558d18SJames Chapman * Tinnel and session create/destroy. 1222fd558d18SJames Chapman *****************************************************************************/ 1223fd558d18SJames Chapman 1224fd558d18SJames Chapman /* Tunnel socket destruct hook. 1225fd558d18SJames Chapman * The tunnel context is deleted only when all session sockets have been 1226fd558d18SJames Chapman * closed. 1227fd558d18SJames Chapman */ 1228fc130840Sstephen hemminger static void l2tp_tunnel_destruct(struct sock *sk) 1229fd558d18SJames Chapman { 12308d8a51e2SDavid S. Miller struct l2tp_tunnel *tunnel = l2tp_tunnel(sk); 1231f8ccac0eSTom Parkin struct l2tp_net *pn; 1232fd558d18SJames Chapman 1233fd558d18SJames Chapman if (tunnel == NULL) 1234fd558d18SJames Chapman goto end; 1235fd558d18SJames Chapman 1236a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: closing...\n", tunnel->name); 1237fd558d18SJames Chapman 1238fd558d18SJames Chapman 1239f8ccac0eSTom Parkin /* Disable udp encapsulation */ 12400d76751fSJames Chapman switch (tunnel->encap) { 12410d76751fSJames Chapman case L2TP_ENCAPTYPE_UDP: 1242fd558d18SJames Chapman /* No longer an encapsulation socket. See net/ipv4/udp.c */ 1243fd558d18SJames Chapman (udp_sk(sk))->encap_type = 0; 1244fd558d18SJames Chapman (udp_sk(sk))->encap_rcv = NULL; 12459980d001STom Parkin (udp_sk(sk))->encap_destroy = NULL; 12460d76751fSJames Chapman break; 12470d76751fSJames Chapman case L2TP_ENCAPTYPE_IP: 12480d76751fSJames Chapman break; 12490d76751fSJames Chapman } 1250fd558d18SJames Chapman 1251fd558d18SJames Chapman /* Remove hooks into tunnel socket */ 1252fd558d18SJames Chapman sk->sk_destruct = tunnel->old_sk_destruct; 1253fd558d18SJames Chapman sk->sk_user_data = NULL; 1254f8ccac0eSTom Parkin tunnel->sock = NULL; 1255f8ccac0eSTom Parkin 1256f8ccac0eSTom Parkin /* Remove the tunnel struct from the tunnel list */ 1257f8ccac0eSTom Parkin pn = l2tp_pernet(tunnel->l2tp_net); 1258f8ccac0eSTom Parkin spin_lock_bh(&pn->l2tp_tunnel_list_lock); 1259f8ccac0eSTom Parkin list_del_rcu(&tunnel->list); 1260f8ccac0eSTom Parkin spin_unlock_bh(&pn->l2tp_tunnel_list_lock); 1261f8ccac0eSTom Parkin atomic_dec(&l2tp_tunnel_count); 1262f8ccac0eSTom Parkin 1263f8ccac0eSTom Parkin l2tp_tunnel_closeall(tunnel); 1264f8ccac0eSTom Parkin l2tp_tunnel_dec_refcount(tunnel); 1265fd558d18SJames Chapman 1266fd558d18SJames Chapman /* Call the original destructor */ 1267fd558d18SJames Chapman if (sk->sk_destruct) 1268fd558d18SJames Chapman (*sk->sk_destruct)(sk); 1269fd558d18SJames Chapman end: 1270fd558d18SJames Chapman return; 1271fd558d18SJames Chapman } 1272fd558d18SJames Chapman 1273fd558d18SJames Chapman /* When the tunnel is closed, all the attached sessions need to go too. 1274fd558d18SJames Chapman */ 1275e34f4c70STom Parkin void l2tp_tunnel_closeall(struct l2tp_tunnel *tunnel) 1276fd558d18SJames Chapman { 1277fd558d18SJames Chapman int hash; 1278fd558d18SJames Chapman struct hlist_node *walk; 1279fd558d18SJames Chapman struct hlist_node *tmp; 1280fd558d18SJames Chapman struct l2tp_session *session; 1281fd558d18SJames Chapman 1282fd558d18SJames Chapman BUG_ON(tunnel == NULL); 1283fd558d18SJames Chapman 1284a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: closing all sessions...\n", 1285a4ca44faSJoe Perches tunnel->name); 1286fd558d18SJames Chapman 1287fd558d18SJames Chapman write_lock_bh(&tunnel->hlist_lock); 1288fd558d18SJames Chapman for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { 1289fd558d18SJames Chapman again: 1290fd558d18SJames Chapman hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) { 1291fd558d18SJames Chapman session = hlist_entry(walk, struct l2tp_session, hlist); 1292fd558d18SJames Chapman 1293a4ca44faSJoe Perches l2tp_info(session, L2TP_MSG_CONTROL, 1294fd558d18SJames Chapman "%s: closing session\n", session->name); 1295fd558d18SJames Chapman 1296fd558d18SJames Chapman hlist_del_init(&session->hlist); 1297fd558d18SJames Chapman 1298fd558d18SJames Chapman if (session->ref != NULL) 1299fd558d18SJames Chapman (*session->ref)(session); 1300fd558d18SJames Chapman 1301fd558d18SJames Chapman write_unlock_bh(&tunnel->hlist_lock); 1302fd558d18SJames Chapman 1303f6e16b29STom Parkin __l2tp_session_unhash(session); 13044c6e2fd3STom Parkin l2tp_session_queue_purge(session); 13054c6e2fd3STom Parkin 1306fd558d18SJames Chapman if (session->session_close != NULL) 1307fd558d18SJames Chapman (*session->session_close)(session); 1308fd558d18SJames Chapman 1309fd558d18SJames Chapman if (session->deref != NULL) 1310fd558d18SJames Chapman (*session->deref)(session); 1311fd558d18SJames Chapman 13129980d001STom Parkin l2tp_session_dec_refcount(session); 13139980d001STom Parkin 1314fd558d18SJames Chapman write_lock_bh(&tunnel->hlist_lock); 1315fd558d18SJames Chapman 1316fd558d18SJames Chapman /* Now restart from the beginning of this hash 1317fd558d18SJames Chapman * chain. We always remove a session from the 1318fd558d18SJames Chapman * list so we are guaranteed to make forward 1319fd558d18SJames Chapman * progress. 1320fd558d18SJames Chapman */ 1321fd558d18SJames Chapman goto again; 1322fd558d18SJames Chapman } 1323fd558d18SJames Chapman } 1324fd558d18SJames Chapman write_unlock_bh(&tunnel->hlist_lock); 1325fd558d18SJames Chapman } 1326e34f4c70STom Parkin EXPORT_SYMBOL_GPL(l2tp_tunnel_closeall); 1327fd558d18SJames Chapman 13289980d001STom Parkin /* Tunnel socket destroy hook for UDP encapsulation */ 13299980d001STom Parkin static void l2tp_udp_encap_destroy(struct sock *sk) 13309980d001STom Parkin { 13319980d001STom Parkin struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk); 13329980d001STom Parkin if (tunnel) { 13339980d001STom Parkin l2tp_tunnel_closeall(tunnel); 13349980d001STom Parkin sock_put(sk); 13359980d001STom Parkin } 13369980d001STom Parkin } 13379980d001STom Parkin 1338f8ccac0eSTom Parkin /* Workqueue tunnel deletion function */ 1339f8ccac0eSTom Parkin static void l2tp_tunnel_del_work(struct work_struct *work) 1340f8ccac0eSTom Parkin { 1341f8ccac0eSTom Parkin struct l2tp_tunnel *tunnel = NULL; 1342f8ccac0eSTom Parkin struct socket *sock = NULL; 1343f8ccac0eSTom Parkin struct sock *sk = NULL; 1344f8ccac0eSTom Parkin 1345f8ccac0eSTom Parkin tunnel = container_of(work, struct l2tp_tunnel, del_work); 134612d656afSRidge Kennedy 134712d656afSRidge Kennedy l2tp_tunnel_closeall(tunnel); 134812d656afSRidge Kennedy 1349f8ccac0eSTom Parkin sk = l2tp_tunnel_sock_lookup(tunnel); 1350f8ccac0eSTom Parkin if (!sk) 135106a15f51SAlexander Couzens goto out; 1352f8ccac0eSTom Parkin 1353f8ccac0eSTom Parkin sock = sk->sk_socket; 1354f8ccac0eSTom Parkin 135502d13ed5STom Parkin /* If the tunnel socket was created by userspace, then go through the 135602d13ed5STom Parkin * inet layer to shut the socket down, and let userspace close it. 135702d13ed5STom Parkin * Otherwise, if we created the socket directly within the kernel, use 135802d13ed5STom Parkin * the sk API to release it here. 1359167eb17eSTom Parkin * In either case the tunnel resources are freed in the socket 1360167eb17eSTom Parkin * destructor when the tunnel socket goes away. 1361f8ccac0eSTom Parkin */ 136202d13ed5STom Parkin if (tunnel->fd >= 0) { 136302d13ed5STom Parkin if (sock) 136402d13ed5STom Parkin inet_shutdown(sock, 2); 136502d13ed5STom Parkin } else { 136626abe143SEric W. Biederman if (sock) { 1367167eb17eSTom Parkin kernel_sock_shutdown(sock, SHUT_RDWR); 136826abe143SEric W. Biederman sock_release(sock); 136926abe143SEric W. Biederman } 1370167eb17eSTom Parkin } 1371f8ccac0eSTom Parkin 1372f8ccac0eSTom Parkin l2tp_tunnel_sock_put(sk); 137306a15f51SAlexander Couzens out: 137406a15f51SAlexander Couzens l2tp_tunnel_dec_refcount(tunnel); 1375fd558d18SJames Chapman } 1376fd558d18SJames Chapman 1377789a4a2cSJames Chapman /* Create a socket for the tunnel, if one isn't set up by 1378789a4a2cSJames Chapman * userspace. This is used for static tunnels where there is no 1379789a4a2cSJames Chapman * managing L2TP daemon. 1380167eb17eSTom Parkin * 1381167eb17eSTom Parkin * Since we don't want these sockets to keep a namespace alive by 1382167eb17eSTom Parkin * themselves, we drop the socket's namespace refcount after creation. 1383167eb17eSTom Parkin * These sockets are freed when the namespace exits using the pernet 1384167eb17eSTom Parkin * exit hook. 1385789a4a2cSJames Chapman */ 1386167eb17eSTom Parkin static int l2tp_tunnel_sock_create(struct net *net, 1387167eb17eSTom Parkin u32 tunnel_id, 1388167eb17eSTom Parkin u32 peer_tunnel_id, 1389167eb17eSTom Parkin struct l2tp_tunnel_cfg *cfg, 1390167eb17eSTom Parkin struct socket **sockp) 1391789a4a2cSJames Chapman { 1392789a4a2cSJames Chapman int err = -EINVAL; 13937bddd0dbSEric Dumazet struct socket *sock = NULL; 139485644b4dSTom Herbert struct udp_port_cfg udp_conf; 1395789a4a2cSJames Chapman 1396789a4a2cSJames Chapman switch (cfg->encap) { 1397789a4a2cSJames Chapman case L2TP_ENCAPTYPE_UDP: 139885644b4dSTom Herbert memset(&udp_conf, 0, sizeof(udp_conf)); 139985644b4dSTom Herbert 1400f9bac8dfSChris Elston #if IS_ENABLED(CONFIG_IPV6) 1401f9bac8dfSChris Elston if (cfg->local_ip6 && cfg->peer_ip6) { 140285644b4dSTom Herbert udp_conf.family = AF_INET6; 140385644b4dSTom Herbert memcpy(&udp_conf.local_ip6, cfg->local_ip6, 140485644b4dSTom Herbert sizeof(udp_conf.local_ip6)); 140585644b4dSTom Herbert memcpy(&udp_conf.peer_ip6, cfg->peer_ip6, 140685644b4dSTom Herbert sizeof(udp_conf.peer_ip6)); 140785644b4dSTom Herbert udp_conf.use_udp6_tx_checksums = 1408018f8258SWang Shanker ! cfg->udp6_zero_tx_checksums; 140985644b4dSTom Herbert udp_conf.use_udp6_rx_checksums = 1410018f8258SWang Shanker ! cfg->udp6_zero_rx_checksums; 1411f9bac8dfSChris Elston } else 1412f9bac8dfSChris Elston #endif 1413f9bac8dfSChris Elston { 141485644b4dSTom Herbert udp_conf.family = AF_INET; 141585644b4dSTom Herbert udp_conf.local_ip = cfg->local_ip; 141685644b4dSTom Herbert udp_conf.peer_ip = cfg->peer_ip; 141785644b4dSTom Herbert udp_conf.use_udp_checksums = cfg->use_udp_checksums; 1418f9bac8dfSChris Elston } 1419789a4a2cSJames Chapman 142085644b4dSTom Herbert udp_conf.local_udp_port = htons(cfg->local_udp_port); 142185644b4dSTom Herbert udp_conf.peer_udp_port = htons(cfg->peer_udp_port); 142285644b4dSTom Herbert 142385644b4dSTom Herbert err = udp_sock_create(net, &udp_conf, &sock); 142485644b4dSTom Herbert if (err < 0) 142585644b4dSTom Herbert goto out; 1426789a4a2cSJames Chapman 1427789a4a2cSJames Chapman break; 1428789a4a2cSJames Chapman 1429789a4a2cSJames Chapman case L2TP_ENCAPTYPE_IP: 1430f9bac8dfSChris Elston #if IS_ENABLED(CONFIG_IPV6) 1431f9bac8dfSChris Elston if (cfg->local_ip6 && cfg->peer_ip6) { 143285644b4dSTom Herbert struct sockaddr_l2tpip6 ip6_addr = {0}; 143385644b4dSTom Herbert 143426abe143SEric W. Biederman err = sock_create_kern(net, AF_INET6, SOCK_DGRAM, 1435167eb17eSTom Parkin IPPROTO_L2TP, &sock); 14365dac94e1SJames Chapman if (err < 0) 1437f9bac8dfSChris Elston goto out; 14385dac94e1SJames Chapman 14395dac94e1SJames Chapman ip6_addr.l2tp_family = AF_INET6; 14405dac94e1SJames Chapman memcpy(&ip6_addr.l2tp_addr, cfg->local_ip6, 14415dac94e1SJames Chapman sizeof(ip6_addr.l2tp_addr)); 14425dac94e1SJames Chapman ip6_addr.l2tp_conn_id = tunnel_id; 14435dac94e1SJames Chapman err = kernel_bind(sock, (struct sockaddr *) &ip6_addr, 14445dac94e1SJames Chapman sizeof(ip6_addr)); 14455dac94e1SJames Chapman if (err < 0) 14465dac94e1SJames Chapman goto out; 14475dac94e1SJames Chapman 14485dac94e1SJames Chapman ip6_addr.l2tp_family = AF_INET6; 14495dac94e1SJames Chapman memcpy(&ip6_addr.l2tp_addr, cfg->peer_ip6, 14505dac94e1SJames Chapman sizeof(ip6_addr.l2tp_addr)); 14515dac94e1SJames Chapman ip6_addr.l2tp_conn_id = peer_tunnel_id; 14525dac94e1SJames Chapman err = kernel_connect(sock, 14535dac94e1SJames Chapman (struct sockaddr *) &ip6_addr, 14545dac94e1SJames Chapman sizeof(ip6_addr), 0); 14555dac94e1SJames Chapman if (err < 0) 14565dac94e1SJames Chapman goto out; 14575dac94e1SJames Chapman } else 1458f9bac8dfSChris Elston #endif 14595dac94e1SJames Chapman { 146085644b4dSTom Herbert struct sockaddr_l2tpip ip_addr = {0}; 146185644b4dSTom Herbert 146226abe143SEric W. Biederman err = sock_create_kern(net, AF_INET, SOCK_DGRAM, 1463167eb17eSTom Parkin IPPROTO_L2TP, &sock); 1464789a4a2cSJames Chapman if (err < 0) 1465789a4a2cSJames Chapman goto out; 1466789a4a2cSJames Chapman 1467789a4a2cSJames Chapman ip_addr.l2tp_family = AF_INET; 1468789a4a2cSJames Chapman ip_addr.l2tp_addr = cfg->local_ip; 1469789a4a2cSJames Chapman ip_addr.l2tp_conn_id = tunnel_id; 14705dac94e1SJames Chapman err = kernel_bind(sock, (struct sockaddr *) &ip_addr, 14715dac94e1SJames Chapman sizeof(ip_addr)); 1472789a4a2cSJames Chapman if (err < 0) 1473789a4a2cSJames Chapman goto out; 1474789a4a2cSJames Chapman 1475789a4a2cSJames Chapman ip_addr.l2tp_family = AF_INET; 1476789a4a2cSJames Chapman ip_addr.l2tp_addr = cfg->peer_ip; 1477789a4a2cSJames Chapman ip_addr.l2tp_conn_id = peer_tunnel_id; 14785dac94e1SJames Chapman err = kernel_connect(sock, (struct sockaddr *) &ip_addr, 14795dac94e1SJames Chapman sizeof(ip_addr), 0); 1480789a4a2cSJames Chapman if (err < 0) 1481789a4a2cSJames Chapman goto out; 14825dac94e1SJames Chapman } 1483789a4a2cSJames Chapman break; 1484789a4a2cSJames Chapman 1485789a4a2cSJames Chapman default: 1486789a4a2cSJames Chapman goto out; 1487789a4a2cSJames Chapman } 1488789a4a2cSJames Chapman 1489789a4a2cSJames Chapman out: 1490167eb17eSTom Parkin *sockp = sock; 1491789a4a2cSJames Chapman if ((err < 0) && sock) { 1492167eb17eSTom Parkin kernel_sock_shutdown(sock, SHUT_RDWR); 149326abe143SEric W. Biederman sock_release(sock); 1494789a4a2cSJames Chapman *sockp = NULL; 1495789a4a2cSJames Chapman } 1496789a4a2cSJames Chapman 1497789a4a2cSJames Chapman return err; 1498789a4a2cSJames Chapman } 1499789a4a2cSJames Chapman 150037159ef2SEric Dumazet static struct lock_class_key l2tp_socket_class; 150137159ef2SEric Dumazet 1502fd558d18SJames Chapman int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32 peer_tunnel_id, struct l2tp_tunnel_cfg *cfg, struct l2tp_tunnel **tunnelp) 1503fd558d18SJames Chapman { 1504fd558d18SJames Chapman struct l2tp_tunnel *tunnel = NULL; 1505fd558d18SJames Chapman int err; 1506fd558d18SJames Chapman struct socket *sock = NULL; 1507fd558d18SJames Chapman struct sock *sk = NULL; 1508fd558d18SJames Chapman struct l2tp_net *pn; 15090d76751fSJames Chapman enum l2tp_encap_type encap = L2TP_ENCAPTYPE_UDP; 1510fd558d18SJames Chapman 1511fd558d18SJames Chapman /* Get the tunnel socket from the fd, which was opened by 1512789a4a2cSJames Chapman * the userspace L2TP daemon. If not specified, create a 1513789a4a2cSJames Chapman * kernel socket. 1514fd558d18SJames Chapman */ 1515789a4a2cSJames Chapman if (fd < 0) { 1516167eb17eSTom Parkin err = l2tp_tunnel_sock_create(net, tunnel_id, peer_tunnel_id, 1517167eb17eSTom Parkin cfg, &sock); 1518789a4a2cSJames Chapman if (err < 0) 1519789a4a2cSJames Chapman goto err; 1520789a4a2cSJames Chapman } else { 1521fd558d18SJames Chapman sock = sockfd_lookup(fd, &err); 1522fd558d18SJames Chapman if (!sock) { 1523cbb95e0cSTom Parkin pr_err("tunl %u: sockfd_lookup(fd=%d) returned %d\n", 1524fd558d18SJames Chapman tunnel_id, fd, err); 1525cbb95e0cSTom Parkin err = -EBADF; 1526cbb95e0cSTom Parkin goto err; 1527cbb95e0cSTom Parkin } 1528cbb95e0cSTom Parkin 1529cbb95e0cSTom Parkin /* Reject namespace mismatches */ 1530cbb95e0cSTom Parkin if (!net_eq(sock_net(sock->sk), net)) { 1531cbb95e0cSTom Parkin pr_err("tunl %u: netns mismatch\n", tunnel_id); 1532cbb95e0cSTom Parkin err = -EINVAL; 1533fd558d18SJames Chapman goto err; 1534fd558d18SJames Chapman } 1535789a4a2cSJames Chapman } 1536fd558d18SJames Chapman 1537fd558d18SJames Chapman sk = sock->sk; 1538fd558d18SJames Chapman 15390d76751fSJames Chapman if (cfg != NULL) 15400d76751fSJames Chapman encap = cfg->encap; 15410d76751fSJames Chapman 1542fd558d18SJames Chapman /* Quick sanity checks */ 15430d76751fSJames Chapman switch (encap) { 15440d76751fSJames Chapman case L2TP_ENCAPTYPE_UDP: 1545fd558d18SJames Chapman err = -EPROTONOSUPPORT; 1546fd558d18SJames Chapman if (sk->sk_protocol != IPPROTO_UDP) { 1547a4ca44faSJoe Perches pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n", 1548fd558d18SJames Chapman tunnel_id, fd, sk->sk_protocol, IPPROTO_UDP); 1549fd558d18SJames Chapman goto err; 1550fd558d18SJames Chapman } 15510d76751fSJames Chapman break; 15520d76751fSJames Chapman case L2TP_ENCAPTYPE_IP: 15530d76751fSJames Chapman err = -EPROTONOSUPPORT; 15540d76751fSJames Chapman if (sk->sk_protocol != IPPROTO_L2TP) { 1555a4ca44faSJoe Perches pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n", 15560d76751fSJames Chapman tunnel_id, fd, sk->sk_protocol, IPPROTO_L2TP); 1557fd558d18SJames Chapman goto err; 1558fd558d18SJames Chapman } 15590d76751fSJames Chapman break; 15600d76751fSJames Chapman } 1561fd558d18SJames Chapman 1562fd558d18SJames Chapman /* Check if this socket has already been prepped */ 15638d8a51e2SDavid S. Miller tunnel = l2tp_tunnel(sk); 1564fd558d18SJames Chapman if (tunnel != NULL) { 1565fd558d18SJames Chapman /* This socket has already been prepped */ 1566fd558d18SJames Chapman err = -EBUSY; 1567fd558d18SJames Chapman goto err; 1568fd558d18SJames Chapman } 1569fd558d18SJames Chapman 1570fd558d18SJames Chapman tunnel = kzalloc(sizeof(struct l2tp_tunnel), GFP_KERNEL); 1571fd558d18SJames Chapman if (tunnel == NULL) { 1572fd558d18SJames Chapman err = -ENOMEM; 1573fd558d18SJames Chapman goto err; 1574fd558d18SJames Chapman } 1575fd558d18SJames Chapman 1576fd558d18SJames Chapman tunnel->version = version; 1577fd558d18SJames Chapman tunnel->tunnel_id = tunnel_id; 1578fd558d18SJames Chapman tunnel->peer_tunnel_id = peer_tunnel_id; 1579fd558d18SJames Chapman tunnel->debug = L2TP_DEFAULT_DEBUG_FLAGS; 1580fd558d18SJames Chapman 1581fd558d18SJames Chapman tunnel->magic = L2TP_TUNNEL_MAGIC; 1582fd558d18SJames Chapman sprintf(&tunnel->name[0], "tunl %u", tunnel_id); 1583fd558d18SJames Chapman rwlock_init(&tunnel->hlist_lock); 1584fd558d18SJames Chapman 1585fd558d18SJames Chapman /* The net we belong to */ 1586fd558d18SJames Chapman tunnel->l2tp_net = net; 1587fd558d18SJames Chapman pn = l2tp_pernet(net); 1588fd558d18SJames Chapman 15890d76751fSJames Chapman if (cfg != NULL) 1590fd558d18SJames Chapman tunnel->debug = cfg->debug; 1591fd558d18SJames Chapman 1592e18503f4SFrançois Cachereul #if IS_ENABLED(CONFIG_IPV6) 1593e18503f4SFrançois Cachereul if (sk->sk_family == PF_INET6) { 1594e18503f4SFrançois Cachereul struct ipv6_pinfo *np = inet6_sk(sk); 1595e18503f4SFrançois Cachereul 1596e18503f4SFrançois Cachereul if (ipv6_addr_v4mapped(&np->saddr) && 1597efe4208fSEric Dumazet ipv6_addr_v4mapped(&sk->sk_v6_daddr)) { 1598e18503f4SFrançois Cachereul struct inet_sock *inet = inet_sk(sk); 1599e18503f4SFrançois Cachereul 1600e18503f4SFrançois Cachereul tunnel->v4mapped = true; 1601e18503f4SFrançois Cachereul inet->inet_saddr = np->saddr.s6_addr32[3]; 1602efe4208fSEric Dumazet inet->inet_rcv_saddr = sk->sk_v6_rcv_saddr.s6_addr32[3]; 1603efe4208fSEric Dumazet inet->inet_daddr = sk->sk_v6_daddr.s6_addr32[3]; 1604e18503f4SFrançois Cachereul } else { 1605e18503f4SFrançois Cachereul tunnel->v4mapped = false; 1606e18503f4SFrançois Cachereul } 1607e18503f4SFrançois Cachereul } 1608e18503f4SFrançois Cachereul #endif 1609e18503f4SFrançois Cachereul 1610fd558d18SJames Chapman /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ 16110d76751fSJames Chapman tunnel->encap = encap; 16120d76751fSJames Chapman if (encap == L2TP_ENCAPTYPE_UDP) { 1613a5c5e2daSGuillaume Nault struct udp_tunnel_sock_cfg udp_cfg = { }; 1614fd558d18SJames Chapman 1615c8fffceaSAndy Zhou udp_cfg.sk_user_data = tunnel; 1616c8fffceaSAndy Zhou udp_cfg.encap_type = UDP_ENCAP_L2TPINUDP; 1617c8fffceaSAndy Zhou udp_cfg.encap_rcv = l2tp_udp_encap_recv; 1618c8fffceaSAndy Zhou udp_cfg.encap_destroy = l2tp_udp_encap_destroy; 1619c8fffceaSAndy Zhou 1620c8fffceaSAndy Zhou setup_udp_tunnel_sock(net, sock, &udp_cfg); 1621c8fffceaSAndy Zhou } else { 1622fd558d18SJames Chapman sk->sk_user_data = tunnel; 1623c8fffceaSAndy Zhou } 1624fd558d18SJames Chapman 1625fd558d18SJames Chapman /* Hook on the tunnel socket destructor so that we can cleanup 1626fd558d18SJames Chapman * if the tunnel socket goes away. 1627fd558d18SJames Chapman */ 1628fd558d18SJames Chapman tunnel->old_sk_destruct = sk->sk_destruct; 1629fd558d18SJames Chapman sk->sk_destruct = &l2tp_tunnel_destruct; 1630fd558d18SJames Chapman tunnel->sock = sk; 163180d84ef3STom Parkin tunnel->fd = fd; 163237159ef2SEric Dumazet lockdep_set_class_and_name(&sk->sk_lock.slock, &l2tp_socket_class, "l2tp_sock"); 163337159ef2SEric Dumazet 1634fd558d18SJames Chapman sk->sk_allocation = GFP_ATOMIC; 1635fd558d18SJames Chapman 1636f8ccac0eSTom Parkin /* Init delete workqueue struct */ 1637f8ccac0eSTom Parkin INIT_WORK(&tunnel->del_work, l2tp_tunnel_del_work); 1638f8ccac0eSTom Parkin 1639fd558d18SJames Chapman /* Add tunnel to our list */ 1640fd558d18SJames Chapman INIT_LIST_HEAD(&tunnel->list); 1641fd558d18SJames Chapman atomic_inc(&l2tp_tunnel_count); 1642fd558d18SJames Chapman 1643fd558d18SJames Chapman /* Bump the reference count. The tunnel context is deleted 16441769192aSEric Dumazet * only when this drops to zero. Must be done before list insertion 1645fd558d18SJames Chapman */ 1646fbea9e07SReshetova, Elena refcount_set(&tunnel->ref_count, 1); 16471769192aSEric Dumazet spin_lock_bh(&pn->l2tp_tunnel_list_lock); 16481769192aSEric Dumazet list_add_rcu(&tunnel->list, &pn->l2tp_tunnel_list); 16491769192aSEric Dumazet spin_unlock_bh(&pn->l2tp_tunnel_list_lock); 1650fd558d18SJames Chapman 1651fd558d18SJames Chapman err = 0; 1652fd558d18SJames Chapman err: 1653fd558d18SJames Chapman if (tunnelp) 1654fd558d18SJames Chapman *tunnelp = tunnel; 1655fd558d18SJames Chapman 1656789a4a2cSJames Chapman /* If tunnel's socket was created by the kernel, it doesn't 1657789a4a2cSJames Chapman * have a file. 1658789a4a2cSJames Chapman */ 1659789a4a2cSJames Chapman if (sock && sock->file) 1660fd558d18SJames Chapman sockfd_put(sock); 1661fd558d18SJames Chapman 1662fd558d18SJames Chapman return err; 1663fd558d18SJames Chapman } 1664fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_tunnel_create); 1665fd558d18SJames Chapman 1666309795f4SJames Chapman /* This function is used by the netlink TUNNEL_DELETE command. 1667309795f4SJames Chapman */ 1668309795f4SJames Chapman int l2tp_tunnel_delete(struct l2tp_tunnel *tunnel) 1669309795f4SJames Chapman { 167006a15f51SAlexander Couzens l2tp_tunnel_inc_refcount(tunnel); 167106a15f51SAlexander Couzens if (false == queue_work(l2tp_wq, &tunnel->del_work)) { 167206a15f51SAlexander Couzens l2tp_tunnel_dec_refcount(tunnel); 167306a15f51SAlexander Couzens return 1; 167406a15f51SAlexander Couzens } 167506a15f51SAlexander Couzens return 0; 1676309795f4SJames Chapman } 1677309795f4SJames Chapman EXPORT_SYMBOL_GPL(l2tp_tunnel_delete); 1678309795f4SJames Chapman 1679fd558d18SJames Chapman /* Really kill the session. 1680fd558d18SJames Chapman */ 1681fd558d18SJames Chapman void l2tp_session_free(struct l2tp_session *session) 1682fd558d18SJames Chapman { 1683f6e16b29STom Parkin struct l2tp_tunnel *tunnel = session->tunnel; 1684fd558d18SJames Chapman 1685fbea9e07SReshetova, Elena BUG_ON(refcount_read(&session->ref_count) != 0); 1686fd558d18SJames Chapman 1687f6e16b29STom Parkin if (tunnel) { 1688fd558d18SJames Chapman BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); 1689fd558d18SJames Chapman if (session->session_id != 0) 1690fd558d18SJames Chapman atomic_dec(&l2tp_session_count); 1691fd558d18SJames Chapman sock_put(tunnel->sock); 1692fd558d18SJames Chapman session->tunnel = NULL; 1693fd558d18SJames Chapman l2tp_tunnel_dec_refcount(tunnel); 1694fd558d18SJames Chapman } 1695fd558d18SJames Chapman 1696fd558d18SJames Chapman kfree(session); 1697fd558d18SJames Chapman } 1698fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_session_free); 1699fd558d18SJames Chapman 1700f6e16b29STom Parkin /* Remove an l2tp session from l2tp_core's hash lists. 1701f6e16b29STom Parkin * Provides a tidyup interface for pseudowire code which can't just route all 1702f6e16b29STom Parkin * shutdown via. l2tp_session_delete and a pseudowire-specific session_close 1703f6e16b29STom Parkin * callback. 1704f6e16b29STom Parkin */ 1705f6e16b29STom Parkin void __l2tp_session_unhash(struct l2tp_session *session) 1706f6e16b29STom Parkin { 1707f6e16b29STom Parkin struct l2tp_tunnel *tunnel = session->tunnel; 1708f6e16b29STom Parkin 1709f6e16b29STom Parkin /* Remove the session from core hashes */ 1710f6e16b29STom Parkin if (tunnel) { 1711f6e16b29STom Parkin /* Remove from the per-tunnel hash */ 1712f6e16b29STom Parkin write_lock_bh(&tunnel->hlist_lock); 1713f6e16b29STom Parkin hlist_del_init(&session->hlist); 1714f6e16b29STom Parkin write_unlock_bh(&tunnel->hlist_lock); 1715f6e16b29STom Parkin 1716f6e16b29STom Parkin /* For L2TPv3 we have a per-net hash: remove from there, too */ 1717f6e16b29STom Parkin if (tunnel->version != L2TP_HDR_VER_2) { 1718f6e16b29STom Parkin struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); 1719f6e16b29STom Parkin spin_lock_bh(&pn->l2tp_session_hlist_lock); 1720f6e16b29STom Parkin hlist_del_init_rcu(&session->global_hlist); 1721f6e16b29STom Parkin spin_unlock_bh(&pn->l2tp_session_hlist_lock); 1722f6e16b29STom Parkin synchronize_rcu(); 1723f6e16b29STom Parkin } 1724f6e16b29STom Parkin } 1725f6e16b29STom Parkin } 1726f6e16b29STom Parkin EXPORT_SYMBOL_GPL(__l2tp_session_unhash); 1727f6e16b29STom Parkin 1728309795f4SJames Chapman /* This function is used by the netlink SESSION_DELETE command and by 1729309795f4SJames Chapman pseudowire modules. 1730309795f4SJames Chapman */ 1731309795f4SJames Chapman int l2tp_session_delete(struct l2tp_session *session) 1732309795f4SJames Chapman { 1733f6e16b29STom Parkin if (session->ref) 1734f6e16b29STom Parkin (*session->ref)(session); 1735f6e16b29STom Parkin __l2tp_session_unhash(session); 17364c6e2fd3STom Parkin l2tp_session_queue_purge(session); 1737309795f4SJames Chapman if (session->session_close != NULL) 1738309795f4SJames Chapman (*session->session_close)(session); 1739f6e16b29STom Parkin if (session->deref) 17401b7c92b9SDan Carpenter (*session->deref)(session); 1741309795f4SJames Chapman l2tp_session_dec_refcount(session); 1742309795f4SJames Chapman return 0; 1743309795f4SJames Chapman } 1744309795f4SJames Chapman EXPORT_SYMBOL_GPL(l2tp_session_delete); 1745309795f4SJames Chapman 1746f7faffa3SJames Chapman /* We come here whenever a session's send_seq, cookie_len or 1747f7faffa3SJames Chapman * l2specific_len parameters are set. 1748f7faffa3SJames Chapman */ 1749bb5016eaSGuillaume Nault void l2tp_session_set_header_len(struct l2tp_session *session, int version) 1750f7faffa3SJames Chapman { 1751f7faffa3SJames Chapman if (version == L2TP_HDR_VER_2) { 1752f7faffa3SJames Chapman session->hdr_len = 6; 1753f7faffa3SJames Chapman if (session->send_seq) 1754f7faffa3SJames Chapman session->hdr_len += 4; 1755f7faffa3SJames Chapman } else { 17560d76751fSJames Chapman session->hdr_len = 4 + session->cookie_len + session->l2specific_len + session->offset; 17570d76751fSJames Chapman if (session->tunnel->encap == L2TP_ENCAPTYPE_UDP) 17580d76751fSJames Chapman session->hdr_len += 4; 1759f7faffa3SJames Chapman } 1760f7faffa3SJames Chapman 1761f7faffa3SJames Chapman } 1762bb5016eaSGuillaume Nault EXPORT_SYMBOL_GPL(l2tp_session_set_header_len); 1763f7faffa3SJames Chapman 1764fd558d18SJames Chapman struct l2tp_session *l2tp_session_create(int priv_size, struct l2tp_tunnel *tunnel, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg) 1765fd558d18SJames Chapman { 1766fd558d18SJames Chapman struct l2tp_session *session; 1767dbdbc73bSGuillaume Nault int err; 1768fd558d18SJames Chapman 1769fd558d18SJames Chapman session = kzalloc(sizeof(struct l2tp_session) + priv_size, GFP_KERNEL); 1770fd558d18SJames Chapman if (session != NULL) { 1771fd558d18SJames Chapman session->magic = L2TP_SESSION_MAGIC; 1772fd558d18SJames Chapman session->tunnel = tunnel; 1773fd558d18SJames Chapman 1774fd558d18SJames Chapman session->session_id = session_id; 1775fd558d18SJames Chapman session->peer_session_id = peer_session_id; 1776d301e325SJames Chapman session->nr = 0; 17778a1631d5SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) 17788a1631d5SJames Chapman session->nr_max = 0xffff; 17798a1631d5SJames Chapman else 17808a1631d5SJames Chapman session->nr_max = 0xffffff; 17818a1631d5SJames Chapman session->nr_window_size = session->nr_max / 2; 1782a0dbd822SJames Chapman session->nr_oos_count_max = 4; 1783a0dbd822SJames Chapman 1784a0dbd822SJames Chapman /* Use NR of first received packet */ 1785a0dbd822SJames Chapman session->reorder_skip = 1; 1786fd558d18SJames Chapman 1787fd558d18SJames Chapman sprintf(&session->name[0], "sess %u/%u", 1788fd558d18SJames Chapman tunnel->tunnel_id, session->session_id); 1789fd558d18SJames Chapman 1790fd558d18SJames Chapman skb_queue_head_init(&session->reorder_q); 1791fd558d18SJames Chapman 1792fd558d18SJames Chapman INIT_HLIST_NODE(&session->hlist); 1793f7faffa3SJames Chapman INIT_HLIST_NODE(&session->global_hlist); 1794fd558d18SJames Chapman 1795fd558d18SJames Chapman /* Inherit debug options from tunnel */ 1796fd558d18SJames Chapman session->debug = tunnel->debug; 1797fd558d18SJames Chapman 1798fd558d18SJames Chapman if (cfg) { 1799f7faffa3SJames Chapman session->pwtype = cfg->pw_type; 1800fd558d18SJames Chapman session->debug = cfg->debug; 1801fd558d18SJames Chapman session->mtu = cfg->mtu; 1802fd558d18SJames Chapman session->mru = cfg->mru; 1803fd558d18SJames Chapman session->send_seq = cfg->send_seq; 1804fd558d18SJames Chapman session->recv_seq = cfg->recv_seq; 1805fd558d18SJames Chapman session->lns_mode = cfg->lns_mode; 1806f7faffa3SJames Chapman session->reorder_timeout = cfg->reorder_timeout; 1807f7faffa3SJames Chapman session->offset = cfg->offset; 1808f7faffa3SJames Chapman session->l2specific_type = cfg->l2specific_type; 1809f7faffa3SJames Chapman session->l2specific_len = cfg->l2specific_len; 1810f7faffa3SJames Chapman session->cookie_len = cfg->cookie_len; 1811f7faffa3SJames Chapman memcpy(&session->cookie[0], &cfg->cookie[0], cfg->cookie_len); 1812f7faffa3SJames Chapman session->peer_cookie_len = cfg->peer_cookie_len; 1813f7faffa3SJames Chapman memcpy(&session->peer_cookie[0], &cfg->peer_cookie[0], cfg->peer_cookie_len); 1814fd558d18SJames Chapman } 1815fd558d18SJames Chapman 1816f7faffa3SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) 1817f7faffa3SJames Chapman session->build_header = l2tp_build_l2tpv2_header; 1818f7faffa3SJames Chapman else 1819f7faffa3SJames Chapman session->build_header = l2tp_build_l2tpv3_header; 1820f7faffa3SJames Chapman 1821f7faffa3SJames Chapman l2tp_session_set_header_len(session, tunnel->version); 1822f7faffa3SJames Chapman 18239ee369a4SGuillaume Nault refcount_set(&session->ref_count, 1); 18249ee369a4SGuillaume Nault 1825dbdbc73bSGuillaume Nault err = l2tp_session_add_to_tunnel(tunnel, session); 1826dbdbc73bSGuillaume Nault if (err) { 1827dbdbc73bSGuillaume Nault kfree(session); 1828dbdbc73bSGuillaume Nault 1829dbdbc73bSGuillaume Nault return ERR_PTR(err); 1830dbdbc73bSGuillaume Nault } 1831dbdbc73bSGuillaume Nault 1832fd558d18SJames Chapman l2tp_tunnel_inc_refcount(tunnel); 1833fd558d18SJames Chapman 1834fd558d18SJames Chapman /* Ensure tunnel socket isn't deleted */ 1835fd558d18SJames Chapman sock_hold(tunnel->sock); 1836fd558d18SJames Chapman 1837fd558d18SJames Chapman /* Ignore management session in session count value */ 1838fd558d18SJames Chapman if (session->session_id != 0) 1839fd558d18SJames Chapman atomic_inc(&l2tp_session_count); 1840fd558d18SJames Chapman 1841fd558d18SJames Chapman return session; 1842fd558d18SJames Chapman } 1843dbdbc73bSGuillaume Nault 1844dbdbc73bSGuillaume Nault return ERR_PTR(-ENOMEM); 1845dbdbc73bSGuillaume Nault } 1846fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_session_create); 1847fd558d18SJames Chapman 1848fd558d18SJames Chapman /***************************************************************************** 1849fd558d18SJames Chapman * Init and cleanup 1850fd558d18SJames Chapman *****************************************************************************/ 1851fd558d18SJames Chapman 1852fd558d18SJames Chapman static __net_init int l2tp_init_net(struct net *net) 1853fd558d18SJames Chapman { 1854e773aaffSJiri Pirko struct l2tp_net *pn = net_generic(net, l2tp_net_id); 1855f7faffa3SJames Chapman int hash; 1856fd558d18SJames Chapman 1857fd558d18SJames Chapman INIT_LIST_HEAD(&pn->l2tp_tunnel_list); 1858e02d494dSJames Chapman spin_lock_init(&pn->l2tp_tunnel_list_lock); 1859fd558d18SJames Chapman 1860f7faffa3SJames Chapman for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) 1861f7faffa3SJames Chapman INIT_HLIST_HEAD(&pn->l2tp_session_hlist[hash]); 1862f7faffa3SJames Chapman 1863e02d494dSJames Chapman spin_lock_init(&pn->l2tp_session_hlist_lock); 1864f7faffa3SJames Chapman 1865fd558d18SJames Chapman return 0; 1866fd558d18SJames Chapman } 1867fd558d18SJames Chapman 1868167eb17eSTom Parkin static __net_exit void l2tp_exit_net(struct net *net) 1869167eb17eSTom Parkin { 1870167eb17eSTom Parkin struct l2tp_net *pn = l2tp_pernet(net); 1871167eb17eSTom Parkin struct l2tp_tunnel *tunnel = NULL; 1872167eb17eSTom Parkin 1873167eb17eSTom Parkin rcu_read_lock_bh(); 1874167eb17eSTom Parkin list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { 1875167eb17eSTom Parkin (void)l2tp_tunnel_delete(tunnel); 1876167eb17eSTom Parkin } 1877167eb17eSTom Parkin rcu_read_unlock_bh(); 18782f86953eSSabrina Dubroca 18792f86953eSSabrina Dubroca flush_workqueue(l2tp_wq); 18802f86953eSSabrina Dubroca rcu_barrier(); 1881167eb17eSTom Parkin } 1882167eb17eSTom Parkin 1883fd558d18SJames Chapman static struct pernet_operations l2tp_net_ops = { 1884fd558d18SJames Chapman .init = l2tp_init_net, 1885167eb17eSTom Parkin .exit = l2tp_exit_net, 1886fd558d18SJames Chapman .id = &l2tp_net_id, 1887fd558d18SJames Chapman .size = sizeof(struct l2tp_net), 1888fd558d18SJames Chapman }; 1889fd558d18SJames Chapman 1890fd558d18SJames Chapman static int __init l2tp_init(void) 1891fd558d18SJames Chapman { 1892fd558d18SJames Chapman int rc = 0; 1893fd558d18SJames Chapman 1894fd558d18SJames Chapman rc = register_pernet_device(&l2tp_net_ops); 1895fd558d18SJames Chapman if (rc) 1896fd558d18SJames Chapman goto out; 1897fd558d18SJames Chapman 189859ff3eb6SZhangZhen l2tp_wq = alloc_workqueue("l2tp", WQ_UNBOUND, 0); 1899f8ccac0eSTom Parkin if (!l2tp_wq) { 1900f8ccac0eSTom Parkin pr_err("alloc_workqueue failed\n"); 190167e04c29SWANG Cong unregister_pernet_device(&l2tp_net_ops); 1902f8ccac0eSTom Parkin rc = -ENOMEM; 1903f8ccac0eSTom Parkin goto out; 1904f8ccac0eSTom Parkin } 1905f8ccac0eSTom Parkin 1906a4ca44faSJoe Perches pr_info("L2TP core driver, %s\n", L2TP_DRV_VERSION); 1907fd558d18SJames Chapman 1908fd558d18SJames Chapman out: 1909fd558d18SJames Chapman return rc; 1910fd558d18SJames Chapman } 1911fd558d18SJames Chapman 1912fd558d18SJames Chapman static void __exit l2tp_exit(void) 1913fd558d18SJames Chapman { 1914fd558d18SJames Chapman unregister_pernet_device(&l2tp_net_ops); 1915f8ccac0eSTom Parkin if (l2tp_wq) { 1916f8ccac0eSTom Parkin destroy_workqueue(l2tp_wq); 1917f8ccac0eSTom Parkin l2tp_wq = NULL; 1918f8ccac0eSTom Parkin } 1919fd558d18SJames Chapman } 1920fd558d18SJames Chapman 1921fd558d18SJames Chapman module_init(l2tp_init); 1922fd558d18SJames Chapman module_exit(l2tp_exit); 1923fd558d18SJames Chapman 1924fd558d18SJames Chapman MODULE_AUTHOR("James Chapman <jchapman@katalix.com>"); 1925fd558d18SJames Chapman MODULE_DESCRIPTION("L2TP core"); 1926fd558d18SJames Chapman MODULE_LICENSE("GPL"); 1927fd558d18SJames Chapman MODULE_VERSION(L2TP_DRV_VERSION); 1928fd558d18SJames Chapman 1929