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> 55309795f4SJames Chapman #include <net/inet_common.h> 56fd558d18SJames Chapman #include <net/xfrm.h> 570d76751fSJames Chapman #include <net/protocol.h> 58d2cf3361SBenjamin LaHaise #include <net/inet6_connection_sock.h> 59d2cf3361SBenjamin LaHaise #include <net/inet_ecn.h> 60d2cf3361SBenjamin LaHaise #include <net/ip6_route.h> 61d499bd2eSDavid S. Miller #include <net/ip6_checksum.h> 62fd558d18SJames Chapman 63fd558d18SJames Chapman #include <asm/byteorder.h> 6460063497SArun Sharma #include <linux/atomic.h> 65fd558d18SJames Chapman 66fd558d18SJames Chapman #include "l2tp_core.h" 67fd558d18SJames Chapman 68fd558d18SJames Chapman #define L2TP_DRV_VERSION "V2.0" 69fd558d18SJames Chapman 70fd558d18SJames Chapman /* L2TP header constants */ 71fd558d18SJames Chapman #define L2TP_HDRFLAG_T 0x8000 72fd558d18SJames Chapman #define L2TP_HDRFLAG_L 0x4000 73fd558d18SJames Chapman #define L2TP_HDRFLAG_S 0x0800 74fd558d18SJames Chapman #define L2TP_HDRFLAG_O 0x0200 75fd558d18SJames Chapman #define L2TP_HDRFLAG_P 0x0100 76fd558d18SJames Chapman 77fd558d18SJames Chapman #define L2TP_HDR_VER_MASK 0x000F 78fd558d18SJames Chapman #define L2TP_HDR_VER_2 0x0002 79f7faffa3SJames Chapman #define L2TP_HDR_VER_3 0x0003 80fd558d18SJames Chapman 81fd558d18SJames Chapman /* L2TPv3 default L2-specific sublayer */ 82fd558d18SJames Chapman #define L2TP_SLFLAG_S 0x40000000 83fd558d18SJames Chapman #define L2TP_SL_SEQ_MASK 0x00ffffff 84fd558d18SJames Chapman 85fd558d18SJames Chapman #define L2TP_HDR_SIZE_SEQ 10 86fd558d18SJames Chapman #define L2TP_HDR_SIZE_NOSEQ 6 87fd558d18SJames Chapman 88fd558d18SJames Chapman /* Default trace flags */ 89fd558d18SJames Chapman #define L2TP_DEFAULT_DEBUG_FLAGS 0 90fd558d18SJames Chapman 91fd558d18SJames Chapman /* Private data stored for received packets in the skb. 92fd558d18SJames Chapman */ 93fd558d18SJames Chapman struct l2tp_skb_cb { 94f7faffa3SJames Chapman u32 ns; 95fd558d18SJames Chapman u16 has_seq; 96fd558d18SJames Chapman u16 length; 97fd558d18SJames Chapman unsigned long expires; 98fd558d18SJames Chapman }; 99fd558d18SJames Chapman 100fd558d18SJames Chapman #define L2TP_SKB_CB(skb) ((struct l2tp_skb_cb *) &skb->cb[sizeof(struct inet_skb_parm)]) 101fd558d18SJames Chapman 102fd558d18SJames Chapman static atomic_t l2tp_tunnel_count; 103fd558d18SJames Chapman static atomic_t l2tp_session_count; 104f8ccac0eSTom Parkin static struct workqueue_struct *l2tp_wq; 105fd558d18SJames Chapman 106fd558d18SJames Chapman /* per-net private data for this module */ 107fd558d18SJames Chapman static unsigned int l2tp_net_id; 108fd558d18SJames Chapman struct l2tp_net { 109fd558d18SJames Chapman struct list_head l2tp_tunnel_list; 110e02d494dSJames Chapman spinlock_t l2tp_tunnel_list_lock; 111f7faffa3SJames Chapman struct hlist_head l2tp_session_hlist[L2TP_HASH_SIZE_2]; 112e02d494dSJames Chapman spinlock_t l2tp_session_hlist_lock; 113fd558d18SJames Chapman }; 114fd558d18SJames Chapman 115fc130840Sstephen hemminger static void l2tp_session_set_header_len(struct l2tp_session *session, int version); 116fc130840Sstephen hemminger static void l2tp_tunnel_free(struct l2tp_tunnel *tunnel); 117fc130840Sstephen hemminger 118fd558d18SJames Chapman static inline struct l2tp_net *l2tp_pernet(struct net *net) 119fd558d18SJames Chapman { 120fd558d18SJames Chapman BUG_ON(!net); 121fd558d18SJames Chapman 122fd558d18SJames Chapman return net_generic(net, l2tp_net_id); 123fd558d18SJames Chapman } 124fd558d18SJames Chapman 125fc130840Sstephen hemminger /* Tunnel reference counts. Incremented per session that is added to 126fc130840Sstephen hemminger * the tunnel. 127fc130840Sstephen hemminger */ 128fc130840Sstephen hemminger static inline void l2tp_tunnel_inc_refcount_1(struct l2tp_tunnel *tunnel) 129fc130840Sstephen hemminger { 130fc130840Sstephen hemminger atomic_inc(&tunnel->ref_count); 131fc130840Sstephen hemminger } 132fc130840Sstephen hemminger 133fc130840Sstephen hemminger static inline void l2tp_tunnel_dec_refcount_1(struct l2tp_tunnel *tunnel) 134fc130840Sstephen hemminger { 135fc130840Sstephen hemminger if (atomic_dec_and_test(&tunnel->ref_count)) 136fc130840Sstephen hemminger l2tp_tunnel_free(tunnel); 137fc130840Sstephen hemminger } 138fc130840Sstephen hemminger #ifdef L2TP_REFCNT_DEBUG 139a4ca44faSJoe Perches #define l2tp_tunnel_inc_refcount(_t) \ 140a4ca44faSJoe Perches do { \ 141a4ca44faSJoe Perches pr_debug("l2tp_tunnel_inc_refcount: %s:%d %s: cnt=%d\n", \ 142a4ca44faSJoe Perches __func__, __LINE__, (_t)->name, \ 143a4ca44faSJoe Perches atomic_read(&_t->ref_count)); \ 144fc130840Sstephen hemminger l2tp_tunnel_inc_refcount_1(_t); \ 145fc130840Sstephen hemminger } while (0) 146a4ca44faSJoe Perches #define l2tp_tunnel_dec_refcount(_t) 147a4ca44faSJoe Perches do { \ 148a4ca44faSJoe Perches pr_debug("l2tp_tunnel_dec_refcount: %s:%d %s: cnt=%d\n", \ 149a4ca44faSJoe Perches __func__, __LINE__, (_t)->name, \ 150a4ca44faSJoe Perches atomic_read(&_t->ref_count)); \ 151fc130840Sstephen hemminger l2tp_tunnel_dec_refcount_1(_t); \ 152fc130840Sstephen hemminger } while (0) 153fc130840Sstephen hemminger #else 154fc130840Sstephen hemminger #define l2tp_tunnel_inc_refcount(t) l2tp_tunnel_inc_refcount_1(t) 155fc130840Sstephen hemminger #define l2tp_tunnel_dec_refcount(t) l2tp_tunnel_dec_refcount_1(t) 156fc130840Sstephen hemminger #endif 157fc130840Sstephen hemminger 158f7faffa3SJames Chapman /* Session hash global list for L2TPv3. 159f7faffa3SJames Chapman * The session_id SHOULD be random according to RFC3931, but several 160f7faffa3SJames Chapman * L2TP implementations use incrementing session_ids. So we do a real 161f7faffa3SJames Chapman * hash on the session_id, rather than a simple bitmask. 162f7faffa3SJames Chapman */ 163f7faffa3SJames Chapman static inline struct hlist_head * 164f7faffa3SJames Chapman l2tp_session_id_hash_2(struct l2tp_net *pn, u32 session_id) 165f7faffa3SJames Chapman { 166f7faffa3SJames Chapman return &pn->l2tp_session_hlist[hash_32(session_id, L2TP_HASH_BITS_2)]; 167f7faffa3SJames Chapman 168f7faffa3SJames Chapman } 169f7faffa3SJames Chapman 17080d84ef3STom Parkin /* Lookup the tunnel socket, possibly involving the fs code if the socket is 17180d84ef3STom Parkin * owned by userspace. A struct sock returned from this function must be 17280d84ef3STom Parkin * released using l2tp_tunnel_sock_put once you're done with it. 17380d84ef3STom Parkin */ 17480d84ef3STom Parkin struct sock *l2tp_tunnel_sock_lookup(struct l2tp_tunnel *tunnel) 17580d84ef3STom Parkin { 17680d84ef3STom Parkin int err = 0; 17780d84ef3STom Parkin struct socket *sock = NULL; 17880d84ef3STom Parkin struct sock *sk = NULL; 17980d84ef3STom Parkin 18080d84ef3STom Parkin if (!tunnel) 18180d84ef3STom Parkin goto out; 18280d84ef3STom Parkin 18380d84ef3STom Parkin if (tunnel->fd >= 0) { 18480d84ef3STom Parkin /* Socket is owned by userspace, who might be in the process 18580d84ef3STom Parkin * of closing it. Look the socket up using the fd to ensure 18680d84ef3STom Parkin * consistency. 18780d84ef3STom Parkin */ 18880d84ef3STom Parkin sock = sockfd_lookup(tunnel->fd, &err); 18980d84ef3STom Parkin if (sock) 19080d84ef3STom Parkin sk = sock->sk; 19180d84ef3STom Parkin } else { 19280d84ef3STom Parkin /* Socket is owned by kernelspace */ 19380d84ef3STom Parkin sk = tunnel->sock; 1948abbbe8fSTom Parkin sock_hold(sk); 19580d84ef3STom Parkin } 19680d84ef3STom Parkin 19780d84ef3STom Parkin out: 19880d84ef3STom Parkin return sk; 19980d84ef3STom Parkin } 20080d84ef3STom Parkin EXPORT_SYMBOL_GPL(l2tp_tunnel_sock_lookup); 20180d84ef3STom Parkin 20280d84ef3STom Parkin /* Drop a reference to a tunnel socket obtained via. l2tp_tunnel_sock_put */ 20380d84ef3STom Parkin void l2tp_tunnel_sock_put(struct sock *sk) 20480d84ef3STom Parkin { 20580d84ef3STom Parkin struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk); 20680d84ef3STom Parkin if (tunnel) { 20780d84ef3STom Parkin if (tunnel->fd >= 0) { 20880d84ef3STom Parkin /* Socket is owned by userspace */ 20980d84ef3STom Parkin sockfd_put(sk->sk_socket); 21080d84ef3STom Parkin } 21180d84ef3STom Parkin sock_put(sk); 21280d84ef3STom Parkin } 2138abbbe8fSTom Parkin sock_put(sk); 21480d84ef3STom Parkin } 21580d84ef3STom Parkin EXPORT_SYMBOL_GPL(l2tp_tunnel_sock_put); 21680d84ef3STom Parkin 217f7faffa3SJames Chapman /* Lookup a session by id in the global session list 218f7faffa3SJames Chapman */ 219f7faffa3SJames Chapman static struct l2tp_session *l2tp_session_find_2(struct net *net, u32 session_id) 220f7faffa3SJames Chapman { 221f7faffa3SJames Chapman struct l2tp_net *pn = l2tp_pernet(net); 222f7faffa3SJames Chapman struct hlist_head *session_list = 223f7faffa3SJames Chapman l2tp_session_id_hash_2(pn, session_id); 224f7faffa3SJames Chapman struct l2tp_session *session; 225f7faffa3SJames Chapman 226e02d494dSJames Chapman rcu_read_lock_bh(); 227b67bfe0dSSasha Levin hlist_for_each_entry_rcu(session, session_list, global_hlist) { 228f7faffa3SJames Chapman if (session->session_id == session_id) { 229e02d494dSJames Chapman rcu_read_unlock_bh(); 230f7faffa3SJames Chapman return session; 231f7faffa3SJames Chapman } 232f7faffa3SJames Chapman } 233e02d494dSJames Chapman rcu_read_unlock_bh(); 234f7faffa3SJames Chapman 235f7faffa3SJames Chapman return NULL; 236f7faffa3SJames Chapman } 237f7faffa3SJames Chapman 238fd558d18SJames Chapman /* Session hash list. 239fd558d18SJames Chapman * The session_id SHOULD be random according to RFC2661, but several 240fd558d18SJames Chapman * L2TP implementations (Cisco and Microsoft) use incrementing 241fd558d18SJames Chapman * session_ids. So we do a real hash on the session_id, rather than a 242fd558d18SJames Chapman * simple bitmask. 243fd558d18SJames Chapman */ 244fd558d18SJames Chapman static inline struct hlist_head * 245fd558d18SJames Chapman l2tp_session_id_hash(struct l2tp_tunnel *tunnel, u32 session_id) 246fd558d18SJames Chapman { 247fd558d18SJames Chapman return &tunnel->session_hlist[hash_32(session_id, L2TP_HASH_BITS)]; 248fd558d18SJames Chapman } 249fd558d18SJames Chapman 250fd558d18SJames Chapman /* Lookup a session by id 251fd558d18SJames Chapman */ 252f7faffa3SJames Chapman struct l2tp_session *l2tp_session_find(struct net *net, struct l2tp_tunnel *tunnel, u32 session_id) 253fd558d18SJames Chapman { 254f7faffa3SJames Chapman struct hlist_head *session_list; 255fd558d18SJames Chapman struct l2tp_session *session; 256fd558d18SJames Chapman 257f7faffa3SJames Chapman /* In L2TPv3, session_ids are unique over all tunnels and we 258f7faffa3SJames Chapman * sometimes need to look them up before we know the 259f7faffa3SJames Chapman * tunnel. 260f7faffa3SJames Chapman */ 261f7faffa3SJames Chapman if (tunnel == NULL) 262f7faffa3SJames Chapman return l2tp_session_find_2(net, session_id); 263f7faffa3SJames Chapman 264f7faffa3SJames Chapman session_list = l2tp_session_id_hash(tunnel, session_id); 265fd558d18SJames Chapman read_lock_bh(&tunnel->hlist_lock); 266b67bfe0dSSasha Levin hlist_for_each_entry(session, session_list, hlist) { 267fd558d18SJames Chapman if (session->session_id == session_id) { 268fd558d18SJames Chapman read_unlock_bh(&tunnel->hlist_lock); 269fd558d18SJames Chapman return session; 270fd558d18SJames Chapman } 271fd558d18SJames Chapman } 272fd558d18SJames Chapman read_unlock_bh(&tunnel->hlist_lock); 273fd558d18SJames Chapman 274fd558d18SJames Chapman return NULL; 275fd558d18SJames Chapman } 276fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_session_find); 277fd558d18SJames Chapman 278fd558d18SJames Chapman struct l2tp_session *l2tp_session_find_nth(struct l2tp_tunnel *tunnel, int nth) 279fd558d18SJames Chapman { 280fd558d18SJames Chapman int hash; 281fd558d18SJames Chapman struct l2tp_session *session; 282fd558d18SJames Chapman int count = 0; 283fd558d18SJames Chapman 284fd558d18SJames Chapman read_lock_bh(&tunnel->hlist_lock); 285fd558d18SJames Chapman for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { 286b67bfe0dSSasha Levin hlist_for_each_entry(session, &tunnel->session_hlist[hash], hlist) { 287fd558d18SJames Chapman if (++count > nth) { 288fd558d18SJames Chapman read_unlock_bh(&tunnel->hlist_lock); 289fd558d18SJames Chapman return session; 290fd558d18SJames Chapman } 291fd558d18SJames Chapman } 292fd558d18SJames Chapman } 293fd558d18SJames Chapman 294fd558d18SJames Chapman read_unlock_bh(&tunnel->hlist_lock); 295fd558d18SJames Chapman 296fd558d18SJames Chapman return NULL; 297fd558d18SJames Chapman } 298fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_session_find_nth); 299fd558d18SJames Chapman 300309795f4SJames Chapman /* Lookup a session by interface name. 301309795f4SJames Chapman * This is very inefficient but is only used by management interfaces. 302309795f4SJames Chapman */ 303309795f4SJames Chapman struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname) 304309795f4SJames Chapman { 305309795f4SJames Chapman struct l2tp_net *pn = l2tp_pernet(net); 306309795f4SJames Chapman int hash; 307309795f4SJames Chapman struct l2tp_session *session; 308309795f4SJames Chapman 309e02d494dSJames Chapman rcu_read_lock_bh(); 310309795f4SJames Chapman for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) { 311b67bfe0dSSasha Levin hlist_for_each_entry_rcu(session, &pn->l2tp_session_hlist[hash], global_hlist) { 312309795f4SJames Chapman if (!strcmp(session->ifname, ifname)) { 313e02d494dSJames Chapman rcu_read_unlock_bh(); 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 } 323309795f4SJames Chapman EXPORT_SYMBOL_GPL(l2tp_session_find_by_ifname); 324309795f4SJames Chapman 325fd558d18SJames Chapman /* Lookup a tunnel by id 326fd558d18SJames Chapman */ 327fd558d18SJames Chapman struct l2tp_tunnel *l2tp_tunnel_find(struct net *net, u32 tunnel_id) 328fd558d18SJames Chapman { 329fd558d18SJames Chapman struct l2tp_tunnel *tunnel; 330fd558d18SJames Chapman struct l2tp_net *pn = l2tp_pernet(net); 331fd558d18SJames Chapman 332e02d494dSJames Chapman rcu_read_lock_bh(); 333e02d494dSJames Chapman list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { 334fd558d18SJames Chapman if (tunnel->tunnel_id == tunnel_id) { 335e02d494dSJames Chapman rcu_read_unlock_bh(); 336fd558d18SJames Chapman return tunnel; 337fd558d18SJames Chapman } 338fd558d18SJames Chapman } 339e02d494dSJames Chapman rcu_read_unlock_bh(); 340fd558d18SJames Chapman 341fd558d18SJames Chapman return NULL; 342fd558d18SJames Chapman } 343fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_tunnel_find); 344fd558d18SJames Chapman 345fd558d18SJames Chapman struct l2tp_tunnel *l2tp_tunnel_find_nth(struct net *net, int nth) 346fd558d18SJames Chapman { 347fd558d18SJames Chapman struct l2tp_net *pn = l2tp_pernet(net); 348fd558d18SJames Chapman struct l2tp_tunnel *tunnel; 349fd558d18SJames Chapman int count = 0; 350fd558d18SJames Chapman 351e02d494dSJames Chapman rcu_read_lock_bh(); 352e02d494dSJames Chapman list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { 353fd558d18SJames Chapman if (++count > nth) { 354e02d494dSJames Chapman rcu_read_unlock_bh(); 355fd558d18SJames Chapman return tunnel; 356fd558d18SJames Chapman } 357fd558d18SJames Chapman } 358fd558d18SJames Chapman 359e02d494dSJames Chapman rcu_read_unlock_bh(); 360fd558d18SJames Chapman 361fd558d18SJames Chapman return NULL; 362fd558d18SJames Chapman } 363fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_tunnel_find_nth); 364fd558d18SJames Chapman 365fd558d18SJames Chapman /***************************************************************************** 366fd558d18SJames Chapman * Receive data handling 367fd558d18SJames Chapman *****************************************************************************/ 368fd558d18SJames Chapman 369fd558d18SJames Chapman /* Queue a skb in order. We come here only if the skb has an L2TP sequence 370fd558d18SJames Chapman * number. 371fd558d18SJames Chapman */ 372fd558d18SJames Chapman static void l2tp_recv_queue_skb(struct l2tp_session *session, struct sk_buff *skb) 373fd558d18SJames Chapman { 374fd558d18SJames Chapman struct sk_buff *skbp; 375fd558d18SJames Chapman struct sk_buff *tmp; 376f7faffa3SJames Chapman u32 ns = L2TP_SKB_CB(skb)->ns; 377fd558d18SJames Chapman 378fd558d18SJames Chapman spin_lock_bh(&session->reorder_q.lock); 379fd558d18SJames Chapman skb_queue_walk_safe(&session->reorder_q, skbp, tmp) { 380fd558d18SJames Chapman if (L2TP_SKB_CB(skbp)->ns > ns) { 381fd558d18SJames Chapman __skb_queue_before(&session->reorder_q, skbp, skb); 382a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 383fd558d18SJames Chapman "%s: pkt %hu, inserted before %hu, reorder_q len=%d\n", 384fd558d18SJames Chapman session->name, ns, L2TP_SKB_CB(skbp)->ns, 385fd558d18SJames Chapman skb_queue_len(&session->reorder_q)); 3867b7c0719STom Parkin atomic_long_inc(&session->stats.rx_oos_packets); 387fd558d18SJames Chapman goto out; 388fd558d18SJames Chapman } 389fd558d18SJames Chapman } 390fd558d18SJames Chapman 391fd558d18SJames Chapman __skb_queue_tail(&session->reorder_q, skb); 392fd558d18SJames Chapman 393fd558d18SJames Chapman out: 394fd558d18SJames Chapman spin_unlock_bh(&session->reorder_q.lock); 395fd558d18SJames Chapman } 396fd558d18SJames Chapman 397fd558d18SJames Chapman /* Dequeue a single skb. 398fd558d18SJames Chapman */ 399fd558d18SJames Chapman static void l2tp_recv_dequeue_skb(struct l2tp_session *session, struct sk_buff *skb) 400fd558d18SJames Chapman { 401fd558d18SJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 402fd558d18SJames Chapman int length = L2TP_SKB_CB(skb)->length; 403fd558d18SJames Chapman 404fd558d18SJames Chapman /* We're about to requeue the skb, so return resources 405fd558d18SJames Chapman * to its current owner (a socket receive buffer). 406fd558d18SJames Chapman */ 407fd558d18SJames Chapman skb_orphan(skb); 408fd558d18SJames Chapman 4097b7c0719STom Parkin atomic_long_inc(&tunnel->stats.rx_packets); 4107b7c0719STom Parkin atomic_long_add(length, &tunnel->stats.rx_bytes); 4117b7c0719STom Parkin atomic_long_inc(&session->stats.rx_packets); 4127b7c0719STom Parkin atomic_long_add(length, &session->stats.rx_bytes); 413fd558d18SJames Chapman 414fd558d18SJames Chapman if (L2TP_SKB_CB(skb)->has_seq) { 415fd558d18SJames Chapman /* Bump our Nr */ 416fd558d18SJames Chapman session->nr++; 417f7faffa3SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) 418f7faffa3SJames Chapman session->nr &= 0xffff; 419f7faffa3SJames Chapman else 420f7faffa3SJames Chapman session->nr &= 0xffffff; 421f7faffa3SJames Chapman 422a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, "%s: updated nr to %hu\n", 423a4ca44faSJoe Perches session->name, session->nr); 424fd558d18SJames Chapman } 425fd558d18SJames Chapman 426fd558d18SJames Chapman /* call private receive handler */ 427fd558d18SJames Chapman if (session->recv_skb != NULL) 428fd558d18SJames Chapman (*session->recv_skb)(session, skb, L2TP_SKB_CB(skb)->length); 429fd558d18SJames Chapman else 430fd558d18SJames Chapman kfree_skb(skb); 431fd558d18SJames Chapman 432fd558d18SJames Chapman if (session->deref) 433fd558d18SJames Chapman (*session->deref)(session); 434fd558d18SJames Chapman } 435fd558d18SJames Chapman 436fd558d18SJames Chapman /* Dequeue skbs from the session's reorder_q, subject to packet order. 437fd558d18SJames Chapman * Skbs that have been in the queue for too long are simply discarded. 438fd558d18SJames Chapman */ 439fd558d18SJames Chapman static void l2tp_recv_dequeue(struct l2tp_session *session) 440fd558d18SJames Chapman { 441fd558d18SJames Chapman struct sk_buff *skb; 442fd558d18SJames Chapman struct sk_buff *tmp; 443fd558d18SJames Chapman 444fd558d18SJames Chapman /* If the pkt at the head of the queue has the nr that we 445fd558d18SJames Chapman * expect to send up next, dequeue it and any other 446fd558d18SJames Chapman * in-sequence packets behind it. 447fd558d18SJames Chapman */ 448e2e210c0SEric Dumazet start: 449fd558d18SJames Chapman spin_lock_bh(&session->reorder_q.lock); 450fd558d18SJames Chapman skb_queue_walk_safe(&session->reorder_q, skb, tmp) { 451fd558d18SJames Chapman if (time_after(jiffies, L2TP_SKB_CB(skb)->expires)) { 4527b7c0719STom Parkin atomic_long_inc(&session->stats.rx_seq_discards); 4537b7c0719STom Parkin atomic_long_inc(&session->stats.rx_errors); 454a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 455a4ca44faSJoe Perches "%s: oos pkt %u len %d discarded (too old), waiting for %u, reorder_q_len=%d\n", 456fd558d18SJames Chapman session->name, L2TP_SKB_CB(skb)->ns, 457fd558d18SJames Chapman L2TP_SKB_CB(skb)->length, session->nr, 458fd558d18SJames Chapman skb_queue_len(&session->reorder_q)); 45938d40b3fSJames Chapman session->reorder_skip = 1; 460fd558d18SJames Chapman __skb_unlink(skb, &session->reorder_q); 461fd558d18SJames Chapman kfree_skb(skb); 462fd558d18SJames Chapman if (session->deref) 463fd558d18SJames Chapman (*session->deref)(session); 464fd558d18SJames Chapman continue; 465fd558d18SJames Chapman } 466fd558d18SJames Chapman 467fd558d18SJames Chapman if (L2TP_SKB_CB(skb)->has_seq) { 46838d40b3fSJames Chapman if (session->reorder_skip) { 469a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 47038d40b3fSJames Chapman "%s: advancing nr to next pkt: %u -> %u", 47138d40b3fSJames Chapman session->name, session->nr, 47238d40b3fSJames Chapman L2TP_SKB_CB(skb)->ns); 47338d40b3fSJames Chapman session->reorder_skip = 0; 47438d40b3fSJames Chapman session->nr = L2TP_SKB_CB(skb)->ns; 47538d40b3fSJames Chapman } 476fd558d18SJames Chapman if (L2TP_SKB_CB(skb)->ns != session->nr) { 477a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 478a4ca44faSJoe Perches "%s: holding oos pkt %u len %d, waiting for %u, reorder_q_len=%d\n", 479fd558d18SJames Chapman session->name, L2TP_SKB_CB(skb)->ns, 480fd558d18SJames Chapman L2TP_SKB_CB(skb)->length, session->nr, 481fd558d18SJames Chapman skb_queue_len(&session->reorder_q)); 482fd558d18SJames Chapman goto out; 483fd558d18SJames Chapman } 484fd558d18SJames Chapman } 485fd558d18SJames Chapman __skb_unlink(skb, &session->reorder_q); 486fd558d18SJames Chapman 487fd558d18SJames Chapman /* Process the skb. We release the queue lock while we 488fd558d18SJames Chapman * do so to let other contexts process the queue. 489fd558d18SJames Chapman */ 490fd558d18SJames Chapman spin_unlock_bh(&session->reorder_q.lock); 491fd558d18SJames Chapman l2tp_recv_dequeue_skb(session, skb); 492e2e210c0SEric Dumazet goto start; 493fd558d18SJames Chapman } 494fd558d18SJames Chapman 495fd558d18SJames Chapman out: 496fd558d18SJames Chapman spin_unlock_bh(&session->reorder_q.lock); 497fd558d18SJames Chapman } 498fd558d18SJames Chapman 499fd558d18SJames Chapman static inline int l2tp_verify_udp_checksum(struct sock *sk, 500fd558d18SJames Chapman struct sk_buff *skb) 501fd558d18SJames Chapman { 502fd558d18SJames Chapman struct udphdr *uh = udp_hdr(skb); 503fd558d18SJames Chapman u16 ulen = ntohs(uh->len); 504fd558d18SJames Chapman __wsum psum; 505fd558d18SJames Chapman 506d2cf3361SBenjamin LaHaise if (sk->sk_no_check || skb_csum_unnecessary(skb)) 507fd558d18SJames Chapman return 0; 508fd558d18SJames Chapman 509d2cf3361SBenjamin LaHaise #if IS_ENABLED(CONFIG_IPV6) 510d2cf3361SBenjamin LaHaise if (sk->sk_family == PF_INET6) { 511d2cf3361SBenjamin LaHaise if (!uh->check) { 512d2cf3361SBenjamin LaHaise LIMIT_NETDEBUG(KERN_INFO "L2TP: IPv6: checksum is 0\n"); 513d2cf3361SBenjamin LaHaise return 1; 514d2cf3361SBenjamin LaHaise } 515d2cf3361SBenjamin LaHaise if ((skb->ip_summed == CHECKSUM_COMPLETE) && 516d2cf3361SBenjamin LaHaise !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, 517d2cf3361SBenjamin LaHaise &ipv6_hdr(skb)->daddr, ulen, 518d2cf3361SBenjamin LaHaise IPPROTO_UDP, skb->csum)) { 519d2cf3361SBenjamin LaHaise skb->ip_summed = CHECKSUM_UNNECESSARY; 520d2cf3361SBenjamin LaHaise return 0; 521d2cf3361SBenjamin LaHaise } 522d2cf3361SBenjamin LaHaise skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr, 523d2cf3361SBenjamin LaHaise &ipv6_hdr(skb)->daddr, 524d2cf3361SBenjamin LaHaise skb->len, IPPROTO_UDP, 525d2cf3361SBenjamin LaHaise 0)); 526d2cf3361SBenjamin LaHaise } else 527d2cf3361SBenjamin LaHaise #endif 528d2cf3361SBenjamin LaHaise { 529d2cf3361SBenjamin LaHaise struct inet_sock *inet; 530d2cf3361SBenjamin LaHaise if (!uh->check) 531d2cf3361SBenjamin LaHaise return 0; 532fd558d18SJames Chapman inet = inet_sk(sk); 533d2cf3361SBenjamin LaHaise psum = csum_tcpudp_nofold(inet->inet_saddr, inet->inet_daddr, 534d2cf3361SBenjamin LaHaise ulen, IPPROTO_UDP, 0); 535fd558d18SJames Chapman 536fd558d18SJames Chapman if ((skb->ip_summed == CHECKSUM_COMPLETE) && 537fd558d18SJames Chapman !csum_fold(csum_add(psum, skb->csum))) 538fd558d18SJames Chapman return 0; 539fd558d18SJames Chapman skb->csum = psum; 540d2cf3361SBenjamin LaHaise } 541fd558d18SJames Chapman 542fd558d18SJames Chapman return __skb_checksum_complete(skb); 543fd558d18SJames Chapman } 544fd558d18SJames Chapman 545f7faffa3SJames Chapman /* Do receive processing of L2TP data frames. We handle both L2TPv2 546f7faffa3SJames Chapman * and L2TPv3 data frames here. 547f7faffa3SJames Chapman * 548f7faffa3SJames Chapman * L2TPv2 Data Message Header 549f7faffa3SJames Chapman * 550f7faffa3SJames Chapman * 0 1 2 3 551f7faffa3SJames 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 552f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 553f7faffa3SJames Chapman * |T|L|x|x|S|x|O|P|x|x|x|x| Ver | Length (opt) | 554f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 555f7faffa3SJames Chapman * | Tunnel ID | Session ID | 556f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 557f7faffa3SJames Chapman * | Ns (opt) | Nr (opt) | 558f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 559f7faffa3SJames Chapman * | Offset Size (opt) | Offset pad... (opt) 560f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 561f7faffa3SJames Chapman * 562f7faffa3SJames Chapman * Data frames are marked by T=0. All other fields are the same as 563f7faffa3SJames Chapman * those in L2TP control frames. 564f7faffa3SJames Chapman * 565f7faffa3SJames Chapman * L2TPv3 Data Message Header 566f7faffa3SJames Chapman * 567f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 568f7faffa3SJames Chapman * | L2TP Session Header | 569f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 570f7faffa3SJames Chapman * | L2-Specific Sublayer | 571f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 572f7faffa3SJames Chapman * | Tunnel Payload ... 573f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 574f7faffa3SJames Chapman * 575f7faffa3SJames Chapman * L2TPv3 Session Header Over IP 576f7faffa3SJames Chapman * 577f7faffa3SJames Chapman * 0 1 2 3 578f7faffa3SJames 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 579f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 580f7faffa3SJames Chapman * | Session ID | 581f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 582f7faffa3SJames Chapman * | Cookie (optional, maximum 64 bits)... 583f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 584f7faffa3SJames Chapman * | 585f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 586f7faffa3SJames Chapman * 587f7faffa3SJames Chapman * L2TPv3 L2-Specific Sublayer Format 588f7faffa3SJames Chapman * 589f7faffa3SJames Chapman * 0 1 2 3 590f7faffa3SJames 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 591f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 592f7faffa3SJames Chapman * |x|S|x|x|x|x|x|x| Sequence Number | 593f7faffa3SJames Chapman * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 594f7faffa3SJames Chapman * 595f7faffa3SJames Chapman * Cookie value, sublayer format and offset (pad) are negotiated with 596f7faffa3SJames Chapman * the peer when the session is set up. Unlike L2TPv2, we do not need 597f7faffa3SJames Chapman * to parse the packet header to determine if optional fields are 598f7faffa3SJames Chapman * present. 599f7faffa3SJames Chapman * 600f7faffa3SJames Chapman * Caller must already have parsed the frame and determined that it is 601f7faffa3SJames Chapman * a data (not control) frame before coming here. Fields up to the 602f7faffa3SJames Chapman * session-id have already been parsed and ptr points to the data 603f7faffa3SJames Chapman * after the session-id. 604f7faffa3SJames Chapman */ 605f7faffa3SJames Chapman void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, 606f7faffa3SJames Chapman unsigned char *ptr, unsigned char *optr, u16 hdrflags, 607f7faffa3SJames Chapman int length, int (*payload_hook)(struct sk_buff *skb)) 608f7faffa3SJames Chapman { 609f7faffa3SJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 610f7faffa3SJames Chapman int offset; 611f7faffa3SJames Chapman u32 ns, nr; 612f7faffa3SJames Chapman 613f7faffa3SJames Chapman /* The ref count is increased since we now hold a pointer to 614f7faffa3SJames Chapman * the session. Take care to decrement the refcnt when exiting 615f7faffa3SJames Chapman * this function from now on... 616f7faffa3SJames Chapman */ 617f7faffa3SJames Chapman l2tp_session_inc_refcount(session); 618f7faffa3SJames Chapman if (session->ref) 619f7faffa3SJames Chapman (*session->ref)(session); 620f7faffa3SJames Chapman 621f7faffa3SJames Chapman /* Parse and check optional cookie */ 622f7faffa3SJames Chapman if (session->peer_cookie_len > 0) { 623f7faffa3SJames Chapman if (memcmp(ptr, &session->peer_cookie[0], session->peer_cookie_len)) { 624a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_DATA, 625f7faffa3SJames Chapman "%s: cookie mismatch (%u/%u). Discarding.\n", 626a4ca44faSJoe Perches tunnel->name, tunnel->tunnel_id, 627a4ca44faSJoe Perches session->session_id); 6287b7c0719STom Parkin atomic_long_inc(&session->stats.rx_cookie_discards); 629f7faffa3SJames Chapman goto discard; 630f7faffa3SJames Chapman } 631f7faffa3SJames Chapman ptr += session->peer_cookie_len; 632f7faffa3SJames Chapman } 633f7faffa3SJames Chapman 634f7faffa3SJames Chapman /* Handle the optional sequence numbers. Sequence numbers are 635f7faffa3SJames Chapman * in different places for L2TPv2 and L2TPv3. 636f7faffa3SJames Chapman * 637f7faffa3SJames Chapman * If we are the LAC, enable/disable sequence numbers under 638f7faffa3SJames Chapman * the control of the LNS. If no sequence numbers present but 639f7faffa3SJames Chapman * we were expecting them, discard frame. 640f7faffa3SJames Chapman */ 641f7faffa3SJames Chapman ns = nr = 0; 642f7faffa3SJames Chapman L2TP_SKB_CB(skb)->has_seq = 0; 643f7faffa3SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) { 644f7faffa3SJames Chapman if (hdrflags & L2TP_HDRFLAG_S) { 645f7faffa3SJames Chapman ns = ntohs(*(__be16 *) ptr); 646f7faffa3SJames Chapman ptr += 2; 647f7faffa3SJames Chapman nr = ntohs(*(__be16 *) ptr); 648f7faffa3SJames Chapman ptr += 2; 649f7faffa3SJames Chapman 650f7faffa3SJames Chapman /* Store L2TP info in the skb */ 651f7faffa3SJames Chapman L2TP_SKB_CB(skb)->ns = ns; 652f7faffa3SJames Chapman L2TP_SKB_CB(skb)->has_seq = 1; 653f7faffa3SJames Chapman 654a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 655f7faffa3SJames Chapman "%s: recv data ns=%u, nr=%u, session nr=%u\n", 656f7faffa3SJames Chapman session->name, ns, nr, session->nr); 657f7faffa3SJames Chapman } 658f7faffa3SJames Chapman } else if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { 659f7faffa3SJames Chapman u32 l2h = ntohl(*(__be32 *) ptr); 660f7faffa3SJames Chapman 661f7faffa3SJames Chapman if (l2h & 0x40000000) { 662f7faffa3SJames Chapman ns = l2h & 0x00ffffff; 663f7faffa3SJames Chapman 664f7faffa3SJames Chapman /* Store L2TP info in the skb */ 665f7faffa3SJames Chapman L2TP_SKB_CB(skb)->ns = ns; 666f7faffa3SJames Chapman L2TP_SKB_CB(skb)->has_seq = 1; 667f7faffa3SJames Chapman 668a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 669f7faffa3SJames Chapman "%s: recv data ns=%u, session nr=%u\n", 670f7faffa3SJames Chapman session->name, ns, session->nr); 671f7faffa3SJames Chapman } 672f7faffa3SJames Chapman } 673f7faffa3SJames Chapman 674f7faffa3SJames Chapman /* Advance past L2-specific header, if present */ 675f7faffa3SJames Chapman ptr += session->l2specific_len; 676f7faffa3SJames Chapman 677f7faffa3SJames Chapman if (L2TP_SKB_CB(skb)->has_seq) { 678f7faffa3SJames Chapman /* Received a packet with sequence numbers. If we're the LNS, 679f7faffa3SJames Chapman * check if we sre sending sequence numbers and if not, 680f7faffa3SJames Chapman * configure it so. 681f7faffa3SJames Chapman */ 682f7faffa3SJames Chapman if ((!session->lns_mode) && (!session->send_seq)) { 683a4ca44faSJoe Perches l2tp_info(session, L2TP_MSG_SEQ, 684f7faffa3SJames Chapman "%s: requested to enable seq numbers by LNS\n", 685f7faffa3SJames Chapman session->name); 686f7faffa3SJames Chapman session->send_seq = -1; 687f7faffa3SJames Chapman l2tp_session_set_header_len(session, tunnel->version); 688f7faffa3SJames Chapman } 689f7faffa3SJames Chapman } else { 690f7faffa3SJames Chapman /* No sequence numbers. 691f7faffa3SJames Chapman * If user has configured mandatory sequence numbers, discard. 692f7faffa3SJames Chapman */ 693f7faffa3SJames Chapman if (session->recv_seq) { 694a4ca44faSJoe Perches l2tp_warn(session, L2TP_MSG_SEQ, 695a4ca44faSJoe Perches "%s: recv data has no seq numbers when required. Discarding.\n", 696a4ca44faSJoe Perches session->name); 6977b7c0719STom Parkin atomic_long_inc(&session->stats.rx_seq_discards); 698f7faffa3SJames Chapman goto discard; 699f7faffa3SJames Chapman } 700f7faffa3SJames Chapman 701f7faffa3SJames Chapman /* If we're the LAC and we're sending sequence numbers, the 702f7faffa3SJames Chapman * LNS has requested that we no longer send sequence numbers. 703f7faffa3SJames Chapman * If we're the LNS and we're sending sequence numbers, the 704f7faffa3SJames Chapman * LAC is broken. Discard the frame. 705f7faffa3SJames Chapman */ 706f7faffa3SJames Chapman if ((!session->lns_mode) && (session->send_seq)) { 707a4ca44faSJoe Perches l2tp_info(session, L2TP_MSG_SEQ, 708f7faffa3SJames Chapman "%s: requested to disable seq numbers by LNS\n", 709f7faffa3SJames Chapman session->name); 710f7faffa3SJames Chapman session->send_seq = 0; 711f7faffa3SJames Chapman l2tp_session_set_header_len(session, tunnel->version); 712f7faffa3SJames Chapman } else if (session->send_seq) { 713a4ca44faSJoe Perches l2tp_warn(session, L2TP_MSG_SEQ, 714a4ca44faSJoe Perches "%s: recv data has no seq numbers when required. Discarding.\n", 715a4ca44faSJoe Perches session->name); 7167b7c0719STom Parkin atomic_long_inc(&session->stats.rx_seq_discards); 717f7faffa3SJames Chapman goto discard; 718f7faffa3SJames Chapman } 719f7faffa3SJames Chapman } 720f7faffa3SJames Chapman 721f7faffa3SJames Chapman /* Session data offset is handled differently for L2TPv2 and 722f7faffa3SJames Chapman * L2TPv3. For L2TPv2, there is an optional 16-bit value in 723f7faffa3SJames Chapman * the header. For L2TPv3, the offset is negotiated using AVPs 724f7faffa3SJames Chapman * in the session setup control protocol. 725f7faffa3SJames Chapman */ 726f7faffa3SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) { 727f7faffa3SJames Chapman /* If offset bit set, skip it. */ 728f7faffa3SJames Chapman if (hdrflags & L2TP_HDRFLAG_O) { 729f7faffa3SJames Chapman offset = ntohs(*(__be16 *)ptr); 730f7faffa3SJames Chapman ptr += 2 + offset; 731f7faffa3SJames Chapman } 732f7faffa3SJames Chapman } else 733f7faffa3SJames Chapman ptr += session->offset; 734f7faffa3SJames Chapman 735f7faffa3SJames Chapman offset = ptr - optr; 736f7faffa3SJames Chapman if (!pskb_may_pull(skb, offset)) 737f7faffa3SJames Chapman goto discard; 738f7faffa3SJames Chapman 739f7faffa3SJames Chapman __skb_pull(skb, offset); 740f7faffa3SJames Chapman 741f7faffa3SJames Chapman /* If caller wants to process the payload before we queue the 742f7faffa3SJames Chapman * packet, do so now. 743f7faffa3SJames Chapman */ 744f7faffa3SJames Chapman if (payload_hook) 745f7faffa3SJames Chapman if ((*payload_hook)(skb)) 746f7faffa3SJames Chapman goto discard; 747f7faffa3SJames Chapman 748f7faffa3SJames Chapman /* Prepare skb for adding to the session's reorder_q. Hold 749f7faffa3SJames Chapman * packets for max reorder_timeout or 1 second if not 750f7faffa3SJames Chapman * reordering. 751f7faffa3SJames Chapman */ 752f7faffa3SJames Chapman L2TP_SKB_CB(skb)->length = length; 753f7faffa3SJames Chapman L2TP_SKB_CB(skb)->expires = jiffies + 754f7faffa3SJames Chapman (session->reorder_timeout ? session->reorder_timeout : HZ); 755f7faffa3SJames Chapman 756f7faffa3SJames Chapman /* Add packet to the session's receive queue. Reordering is done here, if 757f7faffa3SJames Chapman * enabled. Saved L2TP protocol info is stored in skb->sb[]. 758f7faffa3SJames Chapman */ 759f7faffa3SJames Chapman if (L2TP_SKB_CB(skb)->has_seq) { 760f7faffa3SJames Chapman if (session->reorder_timeout != 0) { 761f7faffa3SJames Chapman /* Packet reordering enabled. Add skb to session's 762f7faffa3SJames Chapman * reorder queue, in order of ns. 763f7faffa3SJames Chapman */ 764f7faffa3SJames Chapman l2tp_recv_queue_skb(session, skb); 765f7faffa3SJames Chapman } else { 766f7faffa3SJames Chapman /* Packet reordering disabled. Discard out-of-sequence 767f7faffa3SJames Chapman * packets 768f7faffa3SJames Chapman */ 769f7faffa3SJames Chapman if (L2TP_SKB_CB(skb)->ns != session->nr) { 7707b7c0719STom Parkin atomic_long_inc(&session->stats.rx_seq_discards); 771a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 772a4ca44faSJoe Perches "%s: oos pkt %u len %d discarded, waiting for %u, reorder_q_len=%d\n", 773f7faffa3SJames Chapman session->name, L2TP_SKB_CB(skb)->ns, 774f7faffa3SJames Chapman L2TP_SKB_CB(skb)->length, session->nr, 775f7faffa3SJames Chapman skb_queue_len(&session->reorder_q)); 776f7faffa3SJames Chapman goto discard; 777f7faffa3SJames Chapman } 778f7faffa3SJames Chapman skb_queue_tail(&session->reorder_q, skb); 779f7faffa3SJames Chapman } 780f7faffa3SJames Chapman } else { 781f7faffa3SJames Chapman /* No sequence numbers. Add the skb to the tail of the 782f7faffa3SJames Chapman * reorder queue. This ensures that it will be 783f7faffa3SJames Chapman * delivered after all previous sequenced skbs. 784f7faffa3SJames Chapman */ 785f7faffa3SJames Chapman skb_queue_tail(&session->reorder_q, skb); 786f7faffa3SJames Chapman } 787f7faffa3SJames Chapman 788f7faffa3SJames Chapman /* Try to dequeue as many skbs from reorder_q as we can. */ 789f7faffa3SJames Chapman l2tp_recv_dequeue(session); 790f7faffa3SJames Chapman 791f7faffa3SJames Chapman l2tp_session_dec_refcount(session); 792f7faffa3SJames Chapman 793f7faffa3SJames Chapman return; 794f7faffa3SJames Chapman 795f7faffa3SJames Chapman discard: 7967b7c0719STom Parkin atomic_long_inc(&session->stats.rx_errors); 797f7faffa3SJames Chapman kfree_skb(skb); 798f7faffa3SJames Chapman 799f7faffa3SJames Chapman if (session->deref) 800f7faffa3SJames Chapman (*session->deref)(session); 801f7faffa3SJames Chapman 802f7faffa3SJames Chapman l2tp_session_dec_refcount(session); 803f7faffa3SJames Chapman } 804f7faffa3SJames Chapman EXPORT_SYMBOL(l2tp_recv_common); 805f7faffa3SJames Chapman 80648f72f92STom Parkin /* Drop skbs from the session's reorder_q 80748f72f92STom Parkin */ 80848f72f92STom Parkin int l2tp_session_queue_purge(struct l2tp_session *session) 80948f72f92STom Parkin { 81048f72f92STom Parkin struct sk_buff *skb = NULL; 81148f72f92STom Parkin BUG_ON(!session); 81248f72f92STom Parkin BUG_ON(session->magic != L2TP_SESSION_MAGIC); 81348f72f92STom Parkin while ((skb = skb_dequeue(&session->reorder_q))) { 81448f72f92STom Parkin atomic_long_inc(&session->stats.rx_errors); 81548f72f92STom Parkin kfree_skb(skb); 81648f72f92STom Parkin if (session->deref) 81748f72f92STom Parkin (*session->deref)(session); 81848f72f92STom Parkin } 81948f72f92STom Parkin return 0; 82048f72f92STom Parkin } 82148f72f92STom Parkin EXPORT_SYMBOL_GPL(l2tp_session_queue_purge); 82248f72f92STom Parkin 823fd558d18SJames Chapman /* Internal UDP receive frame. Do the real work of receiving an L2TP data frame 824fd558d18SJames Chapman * here. The skb is not on a list when we get here. 825fd558d18SJames Chapman * Returns 0 if the packet was a data packet and was successfully passed on. 826fd558d18SJames Chapman * Returns 1 if the packet was not a good data packet and could not be 827fd558d18SJames Chapman * forwarded. All such packets are passed up to userspace to deal with. 828fd558d18SJames Chapman */ 829fc130840Sstephen hemminger static int l2tp_udp_recv_core(struct l2tp_tunnel *tunnel, struct sk_buff *skb, 830fd558d18SJames Chapman int (*payload_hook)(struct sk_buff *skb)) 831fd558d18SJames Chapman { 832fd558d18SJames Chapman struct l2tp_session *session = NULL; 833fd558d18SJames Chapman unsigned char *ptr, *optr; 834fd558d18SJames Chapman u16 hdrflags; 835fd558d18SJames Chapman u32 tunnel_id, session_id; 836fd558d18SJames Chapman u16 version; 837f7faffa3SJames Chapman int length; 838fd558d18SJames Chapman 839fd558d18SJames Chapman if (tunnel->sock && l2tp_verify_udp_checksum(tunnel->sock, skb)) 840fd558d18SJames Chapman goto discard_bad_csum; 841fd558d18SJames Chapman 842fd558d18SJames Chapman /* UDP always verifies the packet length. */ 843fd558d18SJames Chapman __skb_pull(skb, sizeof(struct udphdr)); 844fd558d18SJames Chapman 845fd558d18SJames Chapman /* Short packet? */ 846fd558d18SJames Chapman if (!pskb_may_pull(skb, L2TP_HDR_SIZE_SEQ)) { 847a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_DATA, 848a4ca44faSJoe Perches "%s: recv short packet (len=%d)\n", 849a4ca44faSJoe Perches tunnel->name, skb->len); 850fd558d18SJames Chapman goto error; 851fd558d18SJames Chapman } 852fd558d18SJames Chapman 853fd558d18SJames Chapman /* Trace packet contents, if enabled */ 854fd558d18SJames Chapman if (tunnel->debug & L2TP_MSG_DATA) { 855fd558d18SJames Chapman length = min(32u, skb->len); 856fd558d18SJames Chapman if (!pskb_may_pull(skb, length)) 857fd558d18SJames Chapman goto error; 858fd558d18SJames Chapman 859a4ca44faSJoe Perches pr_debug("%s: recv\n", tunnel->name); 860a4ca44faSJoe Perches print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, skb->data, length); 861fd558d18SJames Chapman } 862fd558d18SJames Chapman 863e50e705cSEric Dumazet /* Point to L2TP header */ 864e50e705cSEric Dumazet optr = ptr = skb->data; 865e50e705cSEric Dumazet 866fd558d18SJames Chapman /* Get L2TP header flags */ 867fd558d18SJames Chapman hdrflags = ntohs(*(__be16 *) ptr); 868fd558d18SJames Chapman 869fd558d18SJames Chapman /* Check protocol version */ 870fd558d18SJames Chapman version = hdrflags & L2TP_HDR_VER_MASK; 871fd558d18SJames Chapman if (version != tunnel->version) { 872a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_DATA, 873fd558d18SJames Chapman "%s: recv protocol version mismatch: got %d expected %d\n", 874fd558d18SJames Chapman tunnel->name, version, tunnel->version); 875fd558d18SJames Chapman goto error; 876fd558d18SJames Chapman } 877fd558d18SJames Chapman 878fd558d18SJames Chapman /* Get length of L2TP packet */ 879fd558d18SJames Chapman length = skb->len; 880fd558d18SJames Chapman 881fd558d18SJames Chapman /* If type is control packet, it is handled by userspace. */ 882fd558d18SJames Chapman if (hdrflags & L2TP_HDRFLAG_T) { 883a4ca44faSJoe Perches l2tp_dbg(tunnel, L2TP_MSG_DATA, 884a4ca44faSJoe Perches "%s: recv control packet, len=%d\n", 885a4ca44faSJoe Perches tunnel->name, length); 886fd558d18SJames Chapman goto error; 887fd558d18SJames Chapman } 888fd558d18SJames Chapman 889fd558d18SJames Chapman /* Skip flags */ 890fd558d18SJames Chapman ptr += 2; 891fd558d18SJames Chapman 892f7faffa3SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) { 893fd558d18SJames Chapman /* If length is present, skip it */ 894fd558d18SJames Chapman if (hdrflags & L2TP_HDRFLAG_L) 895fd558d18SJames Chapman ptr += 2; 896fd558d18SJames Chapman 897fd558d18SJames Chapman /* Extract tunnel and session ID */ 898fd558d18SJames Chapman tunnel_id = ntohs(*(__be16 *) ptr); 899fd558d18SJames Chapman ptr += 2; 900fd558d18SJames Chapman session_id = ntohs(*(__be16 *) ptr); 901fd558d18SJames Chapman ptr += 2; 902f7faffa3SJames Chapman } else { 903f7faffa3SJames Chapman ptr += 2; /* skip reserved bits */ 904f7faffa3SJames Chapman tunnel_id = tunnel->tunnel_id; 905f7faffa3SJames Chapman session_id = ntohl(*(__be32 *) ptr); 906f7faffa3SJames Chapman ptr += 4; 907f7faffa3SJames Chapman } 908fd558d18SJames Chapman 909fd558d18SJames Chapman /* Find the session context */ 910f7faffa3SJames Chapman session = l2tp_session_find(tunnel->l2tp_net, tunnel, session_id); 911309795f4SJames Chapman if (!session || !session->recv_skb) { 912fd558d18SJames Chapman /* Not found? Pass to userspace to deal with */ 913a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_DATA, 914f7faffa3SJames Chapman "%s: no session found (%u/%u). Passing up.\n", 915fd558d18SJames Chapman tunnel->name, tunnel_id, session_id); 916fd558d18SJames Chapman goto error; 917fd558d18SJames Chapman } 918fd558d18SJames Chapman 919f7faffa3SJames Chapman l2tp_recv_common(session, skb, ptr, optr, hdrflags, length, payload_hook); 920fd558d18SJames Chapman 921fd558d18SJames Chapman return 0; 922fd558d18SJames Chapman 923fd558d18SJames Chapman discard_bad_csum: 924fd558d18SJames Chapman LIMIT_NETDEBUG("%s: UDP: bad checksum\n", tunnel->name); 925fd558d18SJames Chapman UDP_INC_STATS_USER(tunnel->l2tp_net, UDP_MIB_INERRORS, 0); 9267b7c0719STom Parkin atomic_long_inc(&tunnel->stats.rx_errors); 927fd558d18SJames Chapman kfree_skb(skb); 928fd558d18SJames Chapman 929fd558d18SJames Chapman return 0; 930fd558d18SJames Chapman 931fd558d18SJames Chapman error: 932fd558d18SJames Chapman /* Put UDP header back */ 933fd558d18SJames Chapman __skb_push(skb, sizeof(struct udphdr)); 934fd558d18SJames Chapman 935fd558d18SJames Chapman return 1; 936fd558d18SJames Chapman } 937fd558d18SJames Chapman 938fd558d18SJames Chapman /* UDP encapsulation receive handler. See net/ipv4/udp.c. 939fd558d18SJames Chapman * Return codes: 940fd558d18SJames Chapman * 0 : success. 941fd558d18SJames Chapman * <0: error 942fd558d18SJames Chapman * >0: skb should be passed up to userspace as UDP. 943fd558d18SJames Chapman */ 944fd558d18SJames Chapman int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) 945fd558d18SJames Chapman { 946fd558d18SJames Chapman struct l2tp_tunnel *tunnel; 947fd558d18SJames Chapman 948fd558d18SJames Chapman tunnel = l2tp_sock_to_tunnel(sk); 949fd558d18SJames Chapman if (tunnel == NULL) 950fd558d18SJames Chapman goto pass_up; 951fd558d18SJames Chapman 952a4ca44faSJoe Perches l2tp_dbg(tunnel, L2TP_MSG_DATA, "%s: received %d bytes\n", 953a4ca44faSJoe Perches tunnel->name, skb->len); 954fd558d18SJames Chapman 955fd558d18SJames Chapman if (l2tp_udp_recv_core(tunnel, skb, tunnel->recv_payload_hook)) 956fd558d18SJames Chapman goto pass_up_put; 957fd558d18SJames Chapman 958fd558d18SJames Chapman sock_put(sk); 959fd558d18SJames Chapman return 0; 960fd558d18SJames Chapman 961fd558d18SJames Chapman pass_up_put: 962fd558d18SJames Chapman sock_put(sk); 963fd558d18SJames Chapman pass_up: 964fd558d18SJames Chapman return 1; 965fd558d18SJames Chapman } 966fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_udp_encap_recv); 967fd558d18SJames Chapman 968fd558d18SJames Chapman /************************************************************************ 969fd558d18SJames Chapman * Transmit handling 970fd558d18SJames Chapman ***********************************************************************/ 971fd558d18SJames Chapman 972fd558d18SJames Chapman /* Build an L2TP header for the session into the buffer provided. 973fd558d18SJames Chapman */ 974f7faffa3SJames Chapman static int l2tp_build_l2tpv2_header(struct l2tp_session *session, void *buf) 975fd558d18SJames Chapman { 976f7faffa3SJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 977fd558d18SJames Chapman __be16 *bufp = buf; 978f7faffa3SJames Chapman __be16 *optr = buf; 979fd558d18SJames Chapman u16 flags = L2TP_HDR_VER_2; 980fd558d18SJames Chapman u32 tunnel_id = tunnel->peer_tunnel_id; 981fd558d18SJames Chapman u32 session_id = session->peer_session_id; 982fd558d18SJames Chapman 983fd558d18SJames Chapman if (session->send_seq) 984fd558d18SJames Chapman flags |= L2TP_HDRFLAG_S; 985fd558d18SJames Chapman 986fd558d18SJames Chapman /* Setup L2TP header. */ 987fd558d18SJames Chapman *bufp++ = htons(flags); 988fd558d18SJames Chapman *bufp++ = htons(tunnel_id); 989fd558d18SJames Chapman *bufp++ = htons(session_id); 990fd558d18SJames Chapman if (session->send_seq) { 991fd558d18SJames Chapman *bufp++ = htons(session->ns); 992fd558d18SJames Chapman *bufp++ = 0; 993fd558d18SJames Chapman session->ns++; 994f7faffa3SJames Chapman session->ns &= 0xffff; 995a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, "%s: updated ns to %u\n", 996a4ca44faSJoe Perches session->name, session->ns); 997fd558d18SJames Chapman } 998fd558d18SJames Chapman 999f7faffa3SJames Chapman return bufp - optr; 1000f7faffa3SJames Chapman } 1001f7faffa3SJames Chapman 1002f7faffa3SJames Chapman static int l2tp_build_l2tpv3_header(struct l2tp_session *session, void *buf) 1003fd558d18SJames Chapman { 10040d76751fSJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 1005f7faffa3SJames Chapman char *bufp = buf; 1006f7faffa3SJames Chapman char *optr = bufp; 1007fd558d18SJames Chapman 10080d76751fSJames Chapman /* Setup L2TP header. The header differs slightly for UDP and 10090d76751fSJames Chapman * IP encapsulations. For UDP, there is 4 bytes of flags. 10100d76751fSJames Chapman */ 10110d76751fSJames Chapman if (tunnel->encap == L2TP_ENCAPTYPE_UDP) { 10120d76751fSJames Chapman u16 flags = L2TP_HDR_VER_3; 1013f7faffa3SJames Chapman *((__be16 *) bufp) = htons(flags); 1014f7faffa3SJames Chapman bufp += 2; 1015f7faffa3SJames Chapman *((__be16 *) bufp) = 0; 1016f7faffa3SJames Chapman bufp += 2; 10170d76751fSJames Chapman } 10180d76751fSJames Chapman 1019f7faffa3SJames Chapman *((__be32 *) bufp) = htonl(session->peer_session_id); 1020f7faffa3SJames Chapman bufp += 4; 1021f7faffa3SJames Chapman if (session->cookie_len) { 1022f7faffa3SJames Chapman memcpy(bufp, &session->cookie[0], session->cookie_len); 1023f7faffa3SJames Chapman bufp += session->cookie_len; 1024fd558d18SJames Chapman } 1025f7faffa3SJames Chapman if (session->l2specific_len) { 1026f7faffa3SJames Chapman if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { 1027f7faffa3SJames Chapman u32 l2h = 0; 1028f7faffa3SJames Chapman if (session->send_seq) { 1029f7faffa3SJames Chapman l2h = 0x40000000 | session->ns; 1030f7faffa3SJames Chapman session->ns++; 1031f7faffa3SJames Chapman session->ns &= 0xffffff; 1032a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_SEQ, 1033a4ca44faSJoe Perches "%s: updated ns to %u\n", 1034a4ca44faSJoe Perches session->name, session->ns); 1035f7faffa3SJames Chapman } 1036f7faffa3SJames Chapman 1037f7faffa3SJames Chapman *((__be32 *) bufp) = htonl(l2h); 1038f7faffa3SJames Chapman } 1039f7faffa3SJames Chapman bufp += session->l2specific_len; 1040f7faffa3SJames Chapman } 1041f7faffa3SJames Chapman if (session->offset) 1042f7faffa3SJames Chapman bufp += session->offset; 1043f7faffa3SJames Chapman 1044f7faffa3SJames Chapman return bufp - optr; 1045f7faffa3SJames Chapman } 1046fd558d18SJames Chapman 1047fc130840Sstephen hemminger static int l2tp_xmit_core(struct l2tp_session *session, struct sk_buff *skb, 1048d9d8da80SDavid S. Miller struct flowi *fl, size_t data_len) 1049fd558d18SJames Chapman { 1050fd558d18SJames Chapman struct l2tp_tunnel *tunnel = session->tunnel; 1051fd558d18SJames Chapman unsigned int len = skb->len; 1052fd558d18SJames Chapman int error; 1053fd558d18SJames Chapman 1054fd558d18SJames Chapman /* Debug */ 1055fd558d18SJames Chapman if (session->send_seq) 1056a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_DATA, "%s: send %Zd bytes, ns=%u\n", 1057a4ca44faSJoe Perches session->name, data_len, session->ns - 1); 1058fd558d18SJames Chapman else 1059a4ca44faSJoe Perches l2tp_dbg(session, L2TP_MSG_DATA, "%s: send %Zd bytes\n", 1060a4ca44faSJoe Perches session->name, data_len); 1061fd558d18SJames Chapman 1062fd558d18SJames Chapman if (session->debug & L2TP_MSG_DATA) { 10630d76751fSJames Chapman int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; 10640d76751fSJames Chapman unsigned char *datap = skb->data + uhlen; 1065fd558d18SJames Chapman 1066a4ca44faSJoe Perches pr_debug("%s: xmit\n", session->name); 1067a4ca44faSJoe Perches print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, 1068a4ca44faSJoe Perches datap, min_t(size_t, 32, len - uhlen)); 1069fd558d18SJames Chapman } 1070fd558d18SJames Chapman 1071fd558d18SJames Chapman /* Queue the packet to IP for output */ 10724e15ed4dSShan Wei skb->local_df = 1; 1073d2cf3361SBenjamin LaHaise #if IS_ENABLED(CONFIG_IPV6) 1074d2cf3361SBenjamin LaHaise if (skb->sk->sk_family == PF_INET6) 1075d2cf3361SBenjamin LaHaise error = inet6_csk_xmit(skb, NULL); 1076d2cf3361SBenjamin LaHaise else 1077d2cf3361SBenjamin LaHaise #endif 1078d9d8da80SDavid S. Miller error = ip_queue_xmit(skb, fl); 1079fd558d18SJames Chapman 1080fd558d18SJames Chapman /* Update stats */ 1081fd558d18SJames Chapman if (error >= 0) { 10827b7c0719STom Parkin atomic_long_inc(&tunnel->stats.tx_packets); 10837b7c0719STom Parkin atomic_long_add(len, &tunnel->stats.tx_bytes); 10847b7c0719STom Parkin atomic_long_inc(&session->stats.tx_packets); 10857b7c0719STom Parkin atomic_long_add(len, &session->stats.tx_bytes); 1086fd558d18SJames Chapman } else { 10877b7c0719STom Parkin atomic_long_inc(&tunnel->stats.tx_errors); 10887b7c0719STom Parkin atomic_long_inc(&session->stats.tx_errors); 1089fd558d18SJames Chapman } 1090fd558d18SJames Chapman 1091fd558d18SJames Chapman return 0; 1092fd558d18SJames Chapman } 1093fd558d18SJames Chapman 1094fd558d18SJames Chapman /* Automatically called when the skb is freed. 1095fd558d18SJames Chapman */ 1096fd558d18SJames Chapman static void l2tp_sock_wfree(struct sk_buff *skb) 1097fd558d18SJames Chapman { 1098fd558d18SJames Chapman sock_put(skb->sk); 1099fd558d18SJames Chapman } 1100fd558d18SJames Chapman 1101fd558d18SJames Chapman /* For data skbs that we transmit, we associate with the tunnel socket 1102fd558d18SJames Chapman * but don't do accounting. 1103fd558d18SJames Chapman */ 1104fd558d18SJames Chapman static inline void l2tp_skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 1105fd558d18SJames Chapman { 1106fd558d18SJames Chapman sock_hold(sk); 1107fd558d18SJames Chapman skb->sk = sk; 1108fd558d18SJames Chapman skb->destructor = l2tp_sock_wfree; 1109fd558d18SJames Chapman } 1110fd558d18SJames Chapman 1111d2cf3361SBenjamin LaHaise #if IS_ENABLED(CONFIG_IPV6) 1112d2cf3361SBenjamin LaHaise static void l2tp_xmit_ipv6_csum(struct sock *sk, struct sk_buff *skb, 1113d2cf3361SBenjamin LaHaise int udp_len) 1114d2cf3361SBenjamin LaHaise { 1115d2cf3361SBenjamin LaHaise struct ipv6_pinfo *np = inet6_sk(sk); 1116d2cf3361SBenjamin LaHaise struct udphdr *uh = udp_hdr(skb); 1117d2cf3361SBenjamin LaHaise 1118d2cf3361SBenjamin LaHaise if (!skb_dst(skb) || !skb_dst(skb)->dev || 1119d2cf3361SBenjamin LaHaise !(skb_dst(skb)->dev->features & NETIF_F_IPV6_CSUM)) { 1120d2cf3361SBenjamin LaHaise __wsum csum = skb_checksum(skb, 0, udp_len, 0); 1121d2cf3361SBenjamin LaHaise skb->ip_summed = CHECKSUM_UNNECESSARY; 1122d2cf3361SBenjamin LaHaise uh->check = csum_ipv6_magic(&np->saddr, &np->daddr, udp_len, 1123d2cf3361SBenjamin LaHaise IPPROTO_UDP, csum); 1124d2cf3361SBenjamin LaHaise if (uh->check == 0) 1125d2cf3361SBenjamin LaHaise uh->check = CSUM_MANGLED_0; 1126d2cf3361SBenjamin LaHaise } else { 1127d2cf3361SBenjamin LaHaise skb->ip_summed = CHECKSUM_PARTIAL; 1128d2cf3361SBenjamin LaHaise skb->csum_start = skb_transport_header(skb) - skb->head; 1129d2cf3361SBenjamin LaHaise skb->csum_offset = offsetof(struct udphdr, check); 1130d2cf3361SBenjamin LaHaise uh->check = ~csum_ipv6_magic(&np->saddr, &np->daddr, 1131d2cf3361SBenjamin LaHaise udp_len, IPPROTO_UDP, 0); 1132d2cf3361SBenjamin LaHaise } 1133d2cf3361SBenjamin LaHaise } 1134d2cf3361SBenjamin LaHaise #endif 1135d2cf3361SBenjamin LaHaise 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 __wsum csum; 1148fd558d18SJames Chapman int headroom; 11490d76751fSJames Chapman int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; 11500d76751fSJames Chapman int udp_len; 1151b8c84307SEric Dumazet int ret = NET_XMIT_SUCCESS; 1152fd558d18SJames Chapman 1153fd558d18SJames Chapman /* Check that there's enough headroom in the skb to insert IP, 1154fd558d18SJames Chapman * UDP and L2TP headers. If not enough, expand it to 1155fd558d18SJames Chapman * make room. Adjust truesize. 1156fd558d18SJames Chapman */ 1157fd558d18SJames Chapman headroom = NET_SKB_PAD + sizeof(struct iphdr) + 11580d76751fSJames Chapman uhlen + hdr_len; 1159835acf5dSEric Dumazet if (skb_cow_head(skb, headroom)) { 1160b8c84307SEric Dumazet kfree_skb(skb); 1161b8c84307SEric Dumazet return NET_XMIT_DROP; 1162835acf5dSEric Dumazet } 1163fd558d18SJames Chapman 1164fd558d18SJames Chapman skb_orphan(skb); 1165fd558d18SJames Chapman /* Setup L2TP header */ 1166f7faffa3SJames Chapman session->build_header(session, __skb_push(skb, hdr_len)); 1167fd558d18SJames Chapman 11680d76751fSJames Chapman /* Reset skb netfilter state */ 1169fd558d18SJames Chapman memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); 1170fd558d18SJames Chapman IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | 1171fd558d18SJames Chapman IPSKB_REROUTED); 1172fd558d18SJames Chapman nf_reset(skb); 1173fd558d18SJames Chapman 11746af88da1SDavid S. Miller bh_lock_sock(sk); 11756af88da1SDavid S. Miller if (sock_owned_by_user(sk)) { 1176b8c84307SEric Dumazet kfree_skb(skb); 1177b8c84307SEric Dumazet ret = NET_XMIT_DROP; 11786af88da1SDavid S. Miller goto out_unlock; 11796af88da1SDavid S. Miller } 11806af88da1SDavid S. Miller 1181fd558d18SJames Chapman /* Get routing info from the tunnel socket */ 1182fd558d18SJames Chapman skb_dst_drop(skb); 118371b1391aSFlorian Westphal skb_dst_set(skb, dst_clone(__sk_dst_check(sk, 0))); 11840d76751fSJames Chapman 1185d9d8da80SDavid S. Miller inet = inet_sk(sk); 1186d9d8da80SDavid S. Miller fl = &inet->cork.fl; 11870d76751fSJames Chapman switch (tunnel->encap) { 11880d76751fSJames Chapman case L2TP_ENCAPTYPE_UDP: 11890d76751fSJames Chapman /* Setup UDP header */ 11900d76751fSJames Chapman __skb_push(skb, sizeof(*uh)); 11910d76751fSJames Chapman skb_reset_transport_header(skb); 11920d76751fSJames Chapman uh = udp_hdr(skb); 11930d76751fSJames Chapman uh->source = inet->inet_sport; 11940d76751fSJames Chapman uh->dest = inet->inet_dport; 11950d76751fSJames Chapman udp_len = uhlen + hdr_len + data_len; 11960d76751fSJames Chapman uh->len = htons(udp_len); 11970d76751fSJames Chapman uh->check = 0; 1198fd558d18SJames Chapman 1199fd558d18SJames Chapman /* Calculate UDP checksum if configured to do so */ 1200d2cf3361SBenjamin LaHaise #if IS_ENABLED(CONFIG_IPV6) 1201d2cf3361SBenjamin LaHaise if (sk->sk_family == PF_INET6) 1202d2cf3361SBenjamin LaHaise l2tp_xmit_ipv6_csum(sk, skb, udp_len); 1203d2cf3361SBenjamin LaHaise else 1204d2cf3361SBenjamin LaHaise #endif 1205fd558d18SJames Chapman if (sk->sk_no_check == UDP_CSUM_NOXMIT) 1206fd558d18SJames Chapman skb->ip_summed = CHECKSUM_NONE; 1207fd558d18SJames Chapman else if ((skb_dst(skb) && skb_dst(skb)->dev) && 1208fd558d18SJames Chapman (!(skb_dst(skb)->dev->features & NETIF_F_V4_CSUM))) { 1209fd558d18SJames Chapman skb->ip_summed = CHECKSUM_COMPLETE; 1210fd558d18SJames Chapman csum = skb_checksum(skb, 0, udp_len, 0); 1211fd558d18SJames Chapman uh->check = csum_tcpudp_magic(inet->inet_saddr, 1212fd558d18SJames Chapman inet->inet_daddr, 1213fd558d18SJames Chapman udp_len, IPPROTO_UDP, csum); 1214fd558d18SJames Chapman if (uh->check == 0) 1215fd558d18SJames Chapman uh->check = CSUM_MANGLED_0; 1216fd558d18SJames Chapman } else { 1217fd558d18SJames Chapman skb->ip_summed = CHECKSUM_PARTIAL; 1218fd558d18SJames Chapman skb->csum_start = skb_transport_header(skb) - skb->head; 1219fd558d18SJames Chapman skb->csum_offset = offsetof(struct udphdr, check); 1220fd558d18SJames Chapman uh->check = ~csum_tcpudp_magic(inet->inet_saddr, 1221fd558d18SJames Chapman inet->inet_daddr, 1222fd558d18SJames Chapman udp_len, IPPROTO_UDP, 0); 1223fd558d18SJames Chapman } 12240d76751fSJames Chapman break; 12250d76751fSJames Chapman 12260d76751fSJames Chapman case L2TP_ENCAPTYPE_IP: 12270d76751fSJames Chapman break; 12280d76751fSJames Chapman } 12290d76751fSJames Chapman 12300d76751fSJames Chapman l2tp_skb_set_owner_w(skb, sk); 1231fd558d18SJames Chapman 1232d9d8da80SDavid S. Miller l2tp_xmit_core(session, skb, fl, data_len); 12336af88da1SDavid S. Miller out_unlock: 12346af88da1SDavid S. Miller bh_unlock_sock(sk); 1235fd558d18SJames Chapman 1236b8c84307SEric Dumazet return ret; 1237fd558d18SJames Chapman } 1238fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_xmit_skb); 1239fd558d18SJames Chapman 1240fd558d18SJames Chapman /***************************************************************************** 1241fd558d18SJames Chapman * Tinnel and session create/destroy. 1242fd558d18SJames Chapman *****************************************************************************/ 1243fd558d18SJames Chapman 1244fd558d18SJames Chapman /* Tunnel socket destruct hook. 1245fd558d18SJames Chapman * The tunnel context is deleted only when all session sockets have been 1246fd558d18SJames Chapman * closed. 1247fd558d18SJames Chapman */ 1248fc130840Sstephen hemminger static void l2tp_tunnel_destruct(struct sock *sk) 1249fd558d18SJames Chapman { 1250fd558d18SJames Chapman struct l2tp_tunnel *tunnel; 1251f8ccac0eSTom Parkin struct l2tp_net *pn; 1252fd558d18SJames Chapman 1253fd558d18SJames Chapman tunnel = sk->sk_user_data; 1254fd558d18SJames Chapman if (tunnel == NULL) 1255fd558d18SJames Chapman goto end; 1256fd558d18SJames Chapman 1257a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: closing...\n", tunnel->name); 1258fd558d18SJames Chapman 1259fd558d18SJames Chapman 1260f8ccac0eSTom Parkin /* Disable udp encapsulation */ 12610d76751fSJames Chapman switch (tunnel->encap) { 12620d76751fSJames Chapman case L2TP_ENCAPTYPE_UDP: 1263fd558d18SJames Chapman /* No longer an encapsulation socket. See net/ipv4/udp.c */ 1264fd558d18SJames Chapman (udp_sk(sk))->encap_type = 0; 1265fd558d18SJames Chapman (udp_sk(sk))->encap_rcv = NULL; 12669980d001STom Parkin (udp_sk(sk))->encap_destroy = NULL; 12670d76751fSJames Chapman break; 12680d76751fSJames Chapman case L2TP_ENCAPTYPE_IP: 12690d76751fSJames Chapman break; 12700d76751fSJames Chapman } 1271fd558d18SJames Chapman 1272fd558d18SJames Chapman /* Remove hooks into tunnel socket */ 1273fd558d18SJames Chapman sk->sk_destruct = tunnel->old_sk_destruct; 1274fd558d18SJames Chapman sk->sk_user_data = NULL; 1275f8ccac0eSTom Parkin tunnel->sock = NULL; 1276f8ccac0eSTom Parkin 1277f8ccac0eSTom Parkin /* Remove the tunnel struct from the tunnel list */ 1278f8ccac0eSTom Parkin pn = l2tp_pernet(tunnel->l2tp_net); 1279f8ccac0eSTom Parkin spin_lock_bh(&pn->l2tp_tunnel_list_lock); 1280f8ccac0eSTom Parkin list_del_rcu(&tunnel->list); 1281f8ccac0eSTom Parkin spin_unlock_bh(&pn->l2tp_tunnel_list_lock); 1282f8ccac0eSTom Parkin atomic_dec(&l2tp_tunnel_count); 1283f8ccac0eSTom Parkin 1284f8ccac0eSTom Parkin l2tp_tunnel_closeall(tunnel); 1285f8ccac0eSTom Parkin l2tp_tunnel_dec_refcount(tunnel); 1286fd558d18SJames Chapman 1287fd558d18SJames Chapman /* Call the original destructor */ 1288fd558d18SJames Chapman if (sk->sk_destruct) 1289fd558d18SJames Chapman (*sk->sk_destruct)(sk); 1290fd558d18SJames Chapman end: 1291fd558d18SJames Chapman return; 1292fd558d18SJames Chapman } 1293fd558d18SJames Chapman 1294fd558d18SJames Chapman /* When the tunnel is closed, all the attached sessions need to go too. 1295fd558d18SJames Chapman */ 1296e34f4c70STom Parkin void l2tp_tunnel_closeall(struct l2tp_tunnel *tunnel) 1297fd558d18SJames Chapman { 1298fd558d18SJames Chapman int hash; 1299fd558d18SJames Chapman struct hlist_node *walk; 1300fd558d18SJames Chapman struct hlist_node *tmp; 1301fd558d18SJames Chapman struct l2tp_session *session; 1302fd558d18SJames Chapman 1303fd558d18SJames Chapman BUG_ON(tunnel == NULL); 1304fd558d18SJames Chapman 1305a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: closing all sessions...\n", 1306a4ca44faSJoe Perches tunnel->name); 1307fd558d18SJames Chapman 1308fd558d18SJames Chapman write_lock_bh(&tunnel->hlist_lock); 1309fd558d18SJames Chapman for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { 1310fd558d18SJames Chapman again: 1311fd558d18SJames Chapman hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) { 1312fd558d18SJames Chapman session = hlist_entry(walk, struct l2tp_session, hlist); 1313fd558d18SJames Chapman 1314a4ca44faSJoe Perches l2tp_info(session, L2TP_MSG_CONTROL, 1315fd558d18SJames Chapman "%s: closing session\n", session->name); 1316fd558d18SJames Chapman 1317fd558d18SJames Chapman hlist_del_init(&session->hlist); 1318fd558d18SJames Chapman 1319fd558d18SJames Chapman if (session->ref != NULL) 1320fd558d18SJames Chapman (*session->ref)(session); 1321fd558d18SJames Chapman 1322fd558d18SJames Chapman write_unlock_bh(&tunnel->hlist_lock); 1323fd558d18SJames Chapman 1324f6e16b29STom Parkin __l2tp_session_unhash(session); 13254c6e2fd3STom Parkin l2tp_session_queue_purge(session); 13264c6e2fd3STom Parkin 1327fd558d18SJames Chapman if (session->session_close != NULL) 1328fd558d18SJames Chapman (*session->session_close)(session); 1329fd558d18SJames Chapman 1330fd558d18SJames Chapman if (session->deref != NULL) 1331fd558d18SJames Chapman (*session->deref)(session); 1332fd558d18SJames Chapman 13339980d001STom Parkin l2tp_session_dec_refcount(session); 13349980d001STom Parkin 1335fd558d18SJames Chapman write_lock_bh(&tunnel->hlist_lock); 1336fd558d18SJames Chapman 1337fd558d18SJames Chapman /* Now restart from the beginning of this hash 1338fd558d18SJames Chapman * chain. We always remove a session from the 1339fd558d18SJames Chapman * list so we are guaranteed to make forward 1340fd558d18SJames Chapman * progress. 1341fd558d18SJames Chapman */ 1342fd558d18SJames Chapman goto again; 1343fd558d18SJames Chapman } 1344fd558d18SJames Chapman } 1345fd558d18SJames Chapman write_unlock_bh(&tunnel->hlist_lock); 1346fd558d18SJames Chapman } 1347e34f4c70STom Parkin EXPORT_SYMBOL_GPL(l2tp_tunnel_closeall); 1348fd558d18SJames Chapman 13499980d001STom Parkin /* Tunnel socket destroy hook for UDP encapsulation */ 13509980d001STom Parkin static void l2tp_udp_encap_destroy(struct sock *sk) 13519980d001STom Parkin { 13529980d001STom Parkin struct l2tp_tunnel *tunnel = l2tp_sock_to_tunnel(sk); 13539980d001STom Parkin if (tunnel) { 13549980d001STom Parkin l2tp_tunnel_closeall(tunnel); 13559980d001STom Parkin sock_put(sk); 13569980d001STom Parkin } 13579980d001STom Parkin } 13589980d001STom Parkin 1359fd558d18SJames Chapman /* Really kill the tunnel. 1360fd558d18SJames Chapman * Come here only when all sessions have been cleared from the tunnel. 1361fd558d18SJames Chapman */ 1362fc130840Sstephen hemminger static void l2tp_tunnel_free(struct l2tp_tunnel *tunnel) 1363fd558d18SJames Chapman { 1364fd558d18SJames Chapman BUG_ON(atomic_read(&tunnel->ref_count) != 0); 1365fd558d18SJames Chapman BUG_ON(tunnel->sock != NULL); 1366a4ca44faSJoe Perches l2tp_info(tunnel, L2TP_MSG_CONTROL, "%s: free...\n", tunnel->name); 136799469c32Sxeb@mail.ru kfree_rcu(tunnel, rcu); 1368f8ccac0eSTom Parkin } 1369fd558d18SJames Chapman 1370f8ccac0eSTom Parkin /* Workqueue tunnel deletion function */ 1371f8ccac0eSTom Parkin static void l2tp_tunnel_del_work(struct work_struct *work) 1372f8ccac0eSTom Parkin { 1373f8ccac0eSTom Parkin struct l2tp_tunnel *tunnel = NULL; 1374f8ccac0eSTom Parkin struct socket *sock = NULL; 1375f8ccac0eSTom Parkin struct sock *sk = NULL; 1376f8ccac0eSTom Parkin 1377f8ccac0eSTom Parkin tunnel = container_of(work, struct l2tp_tunnel, del_work); 1378f8ccac0eSTom Parkin sk = l2tp_tunnel_sock_lookup(tunnel); 1379f8ccac0eSTom Parkin if (!sk) 1380f8ccac0eSTom Parkin return; 1381f8ccac0eSTom Parkin 1382f8ccac0eSTom Parkin sock = sk->sk_socket; 1383f8ccac0eSTom Parkin 138402d13ed5STom Parkin /* If the tunnel socket was created by userspace, then go through the 138502d13ed5STom Parkin * inet layer to shut the socket down, and let userspace close it. 138602d13ed5STom Parkin * Otherwise, if we created the socket directly within the kernel, use 138702d13ed5STom Parkin * the sk API to release it here. 1388167eb17eSTom Parkin * In either case the tunnel resources are freed in the socket 1389167eb17eSTom Parkin * destructor when the tunnel socket goes away. 1390f8ccac0eSTom Parkin */ 139102d13ed5STom Parkin if (tunnel->fd >= 0) { 139202d13ed5STom Parkin if (sock) 139302d13ed5STom Parkin inet_shutdown(sock, 2); 139402d13ed5STom Parkin } else { 139502d13ed5STom Parkin if (sock) 1396167eb17eSTom Parkin kernel_sock_shutdown(sock, SHUT_RDWR); 1397167eb17eSTom Parkin sk_release_kernel(sk); 1398167eb17eSTom Parkin } 1399f8ccac0eSTom Parkin 1400f8ccac0eSTom Parkin l2tp_tunnel_sock_put(sk); 1401fd558d18SJames Chapman } 1402fd558d18SJames Chapman 1403789a4a2cSJames Chapman /* Create a socket for the tunnel, if one isn't set up by 1404789a4a2cSJames Chapman * userspace. This is used for static tunnels where there is no 1405789a4a2cSJames Chapman * managing L2TP daemon. 1406167eb17eSTom Parkin * 1407167eb17eSTom Parkin * Since we don't want these sockets to keep a namespace alive by 1408167eb17eSTom Parkin * themselves, we drop the socket's namespace refcount after creation. 1409167eb17eSTom Parkin * These sockets are freed when the namespace exits using the pernet 1410167eb17eSTom Parkin * exit hook. 1411789a4a2cSJames Chapman */ 1412167eb17eSTom Parkin static int l2tp_tunnel_sock_create(struct net *net, 1413167eb17eSTom Parkin u32 tunnel_id, 1414167eb17eSTom Parkin u32 peer_tunnel_id, 1415167eb17eSTom Parkin struct l2tp_tunnel_cfg *cfg, 1416167eb17eSTom Parkin struct socket **sockp) 1417789a4a2cSJames Chapman { 1418789a4a2cSJames Chapman int err = -EINVAL; 14197bddd0dbSEric Dumazet struct socket *sock = NULL; 1420167eb17eSTom Parkin struct sockaddr_in udp_addr = {0}; 1421167eb17eSTom Parkin struct sockaddr_l2tpip ip_addr = {0}; 1422167eb17eSTom Parkin #if IS_ENABLED(CONFIG_IPV6) 1423167eb17eSTom Parkin struct sockaddr_in6 udp6_addr = {0}; 1424167eb17eSTom Parkin struct sockaddr_l2tpip6 ip6_addr = {0}; 1425167eb17eSTom Parkin #endif 1426789a4a2cSJames Chapman 1427789a4a2cSJames Chapman switch (cfg->encap) { 1428789a4a2cSJames Chapman case L2TP_ENCAPTYPE_UDP: 1429f9bac8dfSChris Elston #if IS_ENABLED(CONFIG_IPV6) 1430f9bac8dfSChris Elston if (cfg->local_ip6 && cfg->peer_ip6) { 1431167eb17eSTom Parkin err = sock_create_kern(AF_INET6, SOCK_DGRAM, 0, &sock); 1432f9bac8dfSChris Elston if (err < 0) 1433f9bac8dfSChris Elston goto out; 1434f9bac8dfSChris Elston 1435167eb17eSTom Parkin sk_change_net(sock->sk, net); 1436f9bac8dfSChris Elston 1437f9bac8dfSChris Elston udp6_addr.sin6_family = AF_INET6; 1438f9bac8dfSChris Elston memcpy(&udp6_addr.sin6_addr, cfg->local_ip6, 1439f9bac8dfSChris Elston sizeof(udp6_addr.sin6_addr)); 1440f9bac8dfSChris Elston udp6_addr.sin6_port = htons(cfg->local_udp_port); 1441f9bac8dfSChris Elston err = kernel_bind(sock, (struct sockaddr *) &udp6_addr, 1442f9bac8dfSChris Elston sizeof(udp6_addr)); 1443f9bac8dfSChris Elston if (err < 0) 1444f9bac8dfSChris Elston goto out; 1445f9bac8dfSChris Elston 1446f9bac8dfSChris Elston udp6_addr.sin6_family = AF_INET6; 1447f9bac8dfSChris Elston memcpy(&udp6_addr.sin6_addr, cfg->peer_ip6, 1448f9bac8dfSChris Elston sizeof(udp6_addr.sin6_addr)); 1449f9bac8dfSChris Elston udp6_addr.sin6_port = htons(cfg->peer_udp_port); 1450f9bac8dfSChris Elston err = kernel_connect(sock, 1451f9bac8dfSChris Elston (struct sockaddr *) &udp6_addr, 1452f9bac8dfSChris Elston sizeof(udp6_addr), 0); 1453f9bac8dfSChris Elston if (err < 0) 1454f9bac8dfSChris Elston goto out; 1455f9bac8dfSChris Elston } else 1456f9bac8dfSChris Elston #endif 1457f9bac8dfSChris Elston { 1458167eb17eSTom Parkin err = sock_create_kern(AF_INET, SOCK_DGRAM, 0, &sock); 1459789a4a2cSJames Chapman if (err < 0) 1460789a4a2cSJames Chapman goto out; 1461789a4a2cSJames Chapman 1462167eb17eSTom Parkin sk_change_net(sock->sk, net); 1463789a4a2cSJames Chapman 1464789a4a2cSJames Chapman udp_addr.sin_family = AF_INET; 1465789a4a2cSJames Chapman udp_addr.sin_addr = cfg->local_ip; 1466789a4a2cSJames Chapman udp_addr.sin_port = htons(cfg->local_udp_port); 1467f9bac8dfSChris Elston err = kernel_bind(sock, (struct sockaddr *) &udp_addr, 1468f9bac8dfSChris Elston sizeof(udp_addr)); 1469789a4a2cSJames Chapman if (err < 0) 1470789a4a2cSJames Chapman goto out; 1471789a4a2cSJames Chapman 1472789a4a2cSJames Chapman udp_addr.sin_family = AF_INET; 1473789a4a2cSJames Chapman udp_addr.sin_addr = cfg->peer_ip; 1474789a4a2cSJames Chapman udp_addr.sin_port = htons(cfg->peer_udp_port); 1475f9bac8dfSChris Elston err = kernel_connect(sock, 1476f9bac8dfSChris Elston (struct sockaddr *) &udp_addr, 1477f9bac8dfSChris Elston sizeof(udp_addr), 0); 1478789a4a2cSJames Chapman if (err < 0) 1479789a4a2cSJames Chapman goto out; 1480f9bac8dfSChris Elston } 1481789a4a2cSJames Chapman 1482789a4a2cSJames Chapman if (!cfg->use_udp_checksums) 1483789a4a2cSJames Chapman sock->sk->sk_no_check = UDP_CSUM_NOXMIT; 1484789a4a2cSJames Chapman 1485789a4a2cSJames Chapman break; 1486789a4a2cSJames Chapman 1487789a4a2cSJames Chapman case L2TP_ENCAPTYPE_IP: 1488f9bac8dfSChris Elston #if IS_ENABLED(CONFIG_IPV6) 1489f9bac8dfSChris Elston if (cfg->local_ip6 && cfg->peer_ip6) { 1490167eb17eSTom Parkin err = sock_create_kern(AF_INET6, SOCK_DGRAM, 1491167eb17eSTom Parkin IPPROTO_L2TP, &sock); 14925dac94e1SJames Chapman if (err < 0) 1493f9bac8dfSChris Elston goto out; 14945dac94e1SJames Chapman 1495167eb17eSTom Parkin sk_change_net(sock->sk, net); 14965dac94e1SJames Chapman 14975dac94e1SJames Chapman ip6_addr.l2tp_family = AF_INET6; 14985dac94e1SJames Chapman memcpy(&ip6_addr.l2tp_addr, cfg->local_ip6, 14995dac94e1SJames Chapman sizeof(ip6_addr.l2tp_addr)); 15005dac94e1SJames Chapman ip6_addr.l2tp_conn_id = tunnel_id; 15015dac94e1SJames Chapman err = kernel_bind(sock, (struct sockaddr *) &ip6_addr, 15025dac94e1SJames Chapman sizeof(ip6_addr)); 15035dac94e1SJames Chapman if (err < 0) 15045dac94e1SJames Chapman goto out; 15055dac94e1SJames Chapman 15065dac94e1SJames Chapman ip6_addr.l2tp_family = AF_INET6; 15075dac94e1SJames Chapman memcpy(&ip6_addr.l2tp_addr, cfg->peer_ip6, 15085dac94e1SJames Chapman sizeof(ip6_addr.l2tp_addr)); 15095dac94e1SJames Chapman ip6_addr.l2tp_conn_id = peer_tunnel_id; 15105dac94e1SJames Chapman err = kernel_connect(sock, 15115dac94e1SJames Chapman (struct sockaddr *) &ip6_addr, 15125dac94e1SJames Chapman sizeof(ip6_addr), 0); 15135dac94e1SJames Chapman if (err < 0) 15145dac94e1SJames Chapman goto out; 15155dac94e1SJames Chapman } else 1516f9bac8dfSChris Elston #endif 15175dac94e1SJames Chapman { 1518167eb17eSTom Parkin err = sock_create_kern(AF_INET, SOCK_DGRAM, 1519167eb17eSTom Parkin IPPROTO_L2TP, &sock); 1520789a4a2cSJames Chapman if (err < 0) 1521789a4a2cSJames Chapman goto out; 1522789a4a2cSJames Chapman 1523167eb17eSTom Parkin sk_change_net(sock->sk, net); 1524789a4a2cSJames Chapman 1525789a4a2cSJames Chapman ip_addr.l2tp_family = AF_INET; 1526789a4a2cSJames Chapman ip_addr.l2tp_addr = cfg->local_ip; 1527789a4a2cSJames Chapman ip_addr.l2tp_conn_id = tunnel_id; 15285dac94e1SJames Chapman err = kernel_bind(sock, (struct sockaddr *) &ip_addr, 15295dac94e1SJames Chapman sizeof(ip_addr)); 1530789a4a2cSJames Chapman if (err < 0) 1531789a4a2cSJames Chapman goto out; 1532789a4a2cSJames Chapman 1533789a4a2cSJames Chapman ip_addr.l2tp_family = AF_INET; 1534789a4a2cSJames Chapman ip_addr.l2tp_addr = cfg->peer_ip; 1535789a4a2cSJames Chapman ip_addr.l2tp_conn_id = peer_tunnel_id; 15365dac94e1SJames Chapman err = kernel_connect(sock, (struct sockaddr *) &ip_addr, 15375dac94e1SJames Chapman sizeof(ip_addr), 0); 1538789a4a2cSJames Chapman if (err < 0) 1539789a4a2cSJames Chapman goto out; 15405dac94e1SJames Chapman } 1541789a4a2cSJames Chapman break; 1542789a4a2cSJames Chapman 1543789a4a2cSJames Chapman default: 1544789a4a2cSJames Chapman goto out; 1545789a4a2cSJames Chapman } 1546789a4a2cSJames Chapman 1547789a4a2cSJames Chapman out: 1548167eb17eSTom Parkin *sockp = sock; 1549789a4a2cSJames Chapman if ((err < 0) && sock) { 1550167eb17eSTom Parkin kernel_sock_shutdown(sock, SHUT_RDWR); 1551167eb17eSTom Parkin sk_release_kernel(sock->sk); 1552789a4a2cSJames Chapman *sockp = NULL; 1553789a4a2cSJames Chapman } 1554789a4a2cSJames Chapman 1555789a4a2cSJames Chapman return err; 1556789a4a2cSJames Chapman } 1557789a4a2cSJames Chapman 155837159ef2SEric Dumazet static struct lock_class_key l2tp_socket_class; 155937159ef2SEric Dumazet 1560fd558d18SJames 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) 1561fd558d18SJames Chapman { 1562fd558d18SJames Chapman struct l2tp_tunnel *tunnel = NULL; 1563fd558d18SJames Chapman int err; 1564fd558d18SJames Chapman struct socket *sock = NULL; 1565fd558d18SJames Chapman struct sock *sk = NULL; 1566fd558d18SJames Chapman struct l2tp_net *pn; 15670d76751fSJames Chapman enum l2tp_encap_type encap = L2TP_ENCAPTYPE_UDP; 1568fd558d18SJames Chapman 1569fd558d18SJames Chapman /* Get the tunnel socket from the fd, which was opened by 1570789a4a2cSJames Chapman * the userspace L2TP daemon. If not specified, create a 1571789a4a2cSJames Chapman * kernel socket. 1572fd558d18SJames Chapman */ 1573789a4a2cSJames Chapman if (fd < 0) { 1574167eb17eSTom Parkin err = l2tp_tunnel_sock_create(net, tunnel_id, peer_tunnel_id, 1575167eb17eSTom Parkin cfg, &sock); 1576789a4a2cSJames Chapman if (err < 0) 1577789a4a2cSJames Chapman goto err; 1578789a4a2cSJames Chapman } else { 1579fd558d18SJames Chapman sock = sockfd_lookup(fd, &err); 1580fd558d18SJames Chapman if (!sock) { 1581cbb95e0cSTom Parkin pr_err("tunl %u: sockfd_lookup(fd=%d) returned %d\n", 1582fd558d18SJames Chapman tunnel_id, fd, err); 1583cbb95e0cSTom Parkin err = -EBADF; 1584cbb95e0cSTom Parkin goto err; 1585cbb95e0cSTom Parkin } 1586cbb95e0cSTom Parkin 1587cbb95e0cSTom Parkin /* Reject namespace mismatches */ 1588cbb95e0cSTom Parkin if (!net_eq(sock_net(sock->sk), net)) { 1589cbb95e0cSTom Parkin pr_err("tunl %u: netns mismatch\n", tunnel_id); 1590cbb95e0cSTom Parkin err = -EINVAL; 1591fd558d18SJames Chapman goto err; 1592fd558d18SJames Chapman } 1593789a4a2cSJames Chapman } 1594fd558d18SJames Chapman 1595fd558d18SJames Chapman sk = sock->sk; 1596fd558d18SJames Chapman 15970d76751fSJames Chapman if (cfg != NULL) 15980d76751fSJames Chapman encap = cfg->encap; 15990d76751fSJames Chapman 1600fd558d18SJames Chapman /* Quick sanity checks */ 16010d76751fSJames Chapman switch (encap) { 16020d76751fSJames Chapman case L2TP_ENCAPTYPE_UDP: 1603fd558d18SJames Chapman err = -EPROTONOSUPPORT; 1604fd558d18SJames Chapman if (sk->sk_protocol != IPPROTO_UDP) { 1605a4ca44faSJoe Perches pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n", 1606fd558d18SJames Chapman tunnel_id, fd, sk->sk_protocol, IPPROTO_UDP); 1607fd558d18SJames Chapman goto err; 1608fd558d18SJames Chapman } 16090d76751fSJames Chapman break; 16100d76751fSJames Chapman case L2TP_ENCAPTYPE_IP: 16110d76751fSJames Chapman err = -EPROTONOSUPPORT; 16120d76751fSJames Chapman if (sk->sk_protocol != IPPROTO_L2TP) { 1613a4ca44faSJoe Perches pr_err("tunl %hu: fd %d wrong protocol, got %d, expected %d\n", 16140d76751fSJames Chapman tunnel_id, fd, sk->sk_protocol, IPPROTO_L2TP); 1615fd558d18SJames Chapman goto err; 1616fd558d18SJames Chapman } 16170d76751fSJames Chapman break; 16180d76751fSJames Chapman } 1619fd558d18SJames Chapman 1620fd558d18SJames Chapman /* Check if this socket has already been prepped */ 1621fd558d18SJames Chapman tunnel = (struct l2tp_tunnel *)sk->sk_user_data; 1622fd558d18SJames Chapman if (tunnel != NULL) { 1623fd558d18SJames Chapman /* This socket has already been prepped */ 1624fd558d18SJames Chapman err = -EBUSY; 1625fd558d18SJames Chapman goto err; 1626fd558d18SJames Chapman } 1627fd558d18SJames Chapman 1628fd558d18SJames Chapman tunnel = kzalloc(sizeof(struct l2tp_tunnel), GFP_KERNEL); 1629fd558d18SJames Chapman if (tunnel == NULL) { 1630fd558d18SJames Chapman err = -ENOMEM; 1631fd558d18SJames Chapman goto err; 1632fd558d18SJames Chapman } 1633fd558d18SJames Chapman 1634fd558d18SJames Chapman tunnel->version = version; 1635fd558d18SJames Chapman tunnel->tunnel_id = tunnel_id; 1636fd558d18SJames Chapman tunnel->peer_tunnel_id = peer_tunnel_id; 1637fd558d18SJames Chapman tunnel->debug = L2TP_DEFAULT_DEBUG_FLAGS; 1638fd558d18SJames Chapman 1639fd558d18SJames Chapman tunnel->magic = L2TP_TUNNEL_MAGIC; 1640fd558d18SJames Chapman sprintf(&tunnel->name[0], "tunl %u", tunnel_id); 1641fd558d18SJames Chapman rwlock_init(&tunnel->hlist_lock); 1642fd558d18SJames Chapman 1643fd558d18SJames Chapman /* The net we belong to */ 1644fd558d18SJames Chapman tunnel->l2tp_net = net; 1645fd558d18SJames Chapman pn = l2tp_pernet(net); 1646fd558d18SJames Chapman 16470d76751fSJames Chapman if (cfg != NULL) 1648fd558d18SJames Chapman tunnel->debug = cfg->debug; 1649fd558d18SJames Chapman 1650fd558d18SJames Chapman /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ 16510d76751fSJames Chapman tunnel->encap = encap; 16520d76751fSJames Chapman if (encap == L2TP_ENCAPTYPE_UDP) { 16530d76751fSJames Chapman /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ 1654fd558d18SJames Chapman udp_sk(sk)->encap_type = UDP_ENCAP_L2TPINUDP; 1655fd558d18SJames Chapman udp_sk(sk)->encap_rcv = l2tp_udp_encap_recv; 16569980d001STom Parkin udp_sk(sk)->encap_destroy = l2tp_udp_encap_destroy; 1657d2cf3361SBenjamin LaHaise #if IS_ENABLED(CONFIG_IPV6) 1658d2cf3361SBenjamin LaHaise if (sk->sk_family == PF_INET6) 1659d2cf3361SBenjamin LaHaise udpv6_encap_enable(); 1660d2cf3361SBenjamin LaHaise else 1661d2cf3361SBenjamin LaHaise #endif 1662447167bfSEric Dumazet udp_encap_enable(); 16630d76751fSJames Chapman } 1664fd558d18SJames Chapman 1665fd558d18SJames Chapman sk->sk_user_data = tunnel; 1666fd558d18SJames Chapman 1667fd558d18SJames Chapman /* Hook on the tunnel socket destructor so that we can cleanup 1668fd558d18SJames Chapman * if the tunnel socket goes away. 1669fd558d18SJames Chapman */ 1670fd558d18SJames Chapman tunnel->old_sk_destruct = sk->sk_destruct; 1671fd558d18SJames Chapman sk->sk_destruct = &l2tp_tunnel_destruct; 1672fd558d18SJames Chapman tunnel->sock = sk; 167380d84ef3STom Parkin tunnel->fd = fd; 167437159ef2SEric Dumazet lockdep_set_class_and_name(&sk->sk_lock.slock, &l2tp_socket_class, "l2tp_sock"); 167537159ef2SEric Dumazet 1676fd558d18SJames Chapman sk->sk_allocation = GFP_ATOMIC; 1677fd558d18SJames Chapman 1678f8ccac0eSTom Parkin /* Init delete workqueue struct */ 1679f8ccac0eSTom Parkin INIT_WORK(&tunnel->del_work, l2tp_tunnel_del_work); 1680f8ccac0eSTom Parkin 1681fd558d18SJames Chapman /* Add tunnel to our list */ 1682fd558d18SJames Chapman INIT_LIST_HEAD(&tunnel->list); 1683fd558d18SJames Chapman atomic_inc(&l2tp_tunnel_count); 1684fd558d18SJames Chapman 1685fd558d18SJames Chapman /* Bump the reference count. The tunnel context is deleted 16861769192aSEric Dumazet * only when this drops to zero. Must be done before list insertion 1687fd558d18SJames Chapman */ 1688fd558d18SJames Chapman l2tp_tunnel_inc_refcount(tunnel); 16891769192aSEric Dumazet spin_lock_bh(&pn->l2tp_tunnel_list_lock); 16901769192aSEric Dumazet list_add_rcu(&tunnel->list, &pn->l2tp_tunnel_list); 16911769192aSEric Dumazet spin_unlock_bh(&pn->l2tp_tunnel_list_lock); 1692fd558d18SJames Chapman 1693fd558d18SJames Chapman err = 0; 1694fd558d18SJames Chapman err: 1695fd558d18SJames Chapman if (tunnelp) 1696fd558d18SJames Chapman *tunnelp = tunnel; 1697fd558d18SJames Chapman 1698789a4a2cSJames Chapman /* If tunnel's socket was created by the kernel, it doesn't 1699789a4a2cSJames Chapman * have a file. 1700789a4a2cSJames Chapman */ 1701789a4a2cSJames Chapman if (sock && sock->file) 1702fd558d18SJames Chapman sockfd_put(sock); 1703fd558d18SJames Chapman 1704fd558d18SJames Chapman return err; 1705fd558d18SJames Chapman } 1706fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_tunnel_create); 1707fd558d18SJames Chapman 1708309795f4SJames Chapman /* This function is used by the netlink TUNNEL_DELETE command. 1709309795f4SJames Chapman */ 1710309795f4SJames Chapman int l2tp_tunnel_delete(struct l2tp_tunnel *tunnel) 1711309795f4SJames Chapman { 17122b551c6eSTom Parkin l2tp_tunnel_closeall(tunnel); 1713f8ccac0eSTom Parkin return (false == queue_work(l2tp_wq, &tunnel->del_work)); 1714309795f4SJames Chapman } 1715309795f4SJames Chapman EXPORT_SYMBOL_GPL(l2tp_tunnel_delete); 1716309795f4SJames Chapman 1717fd558d18SJames Chapman /* Really kill the session. 1718fd558d18SJames Chapman */ 1719fd558d18SJames Chapman void l2tp_session_free(struct l2tp_session *session) 1720fd558d18SJames Chapman { 1721f6e16b29STom Parkin struct l2tp_tunnel *tunnel = session->tunnel; 1722fd558d18SJames Chapman 1723fd558d18SJames Chapman BUG_ON(atomic_read(&session->ref_count) != 0); 1724fd558d18SJames Chapman 1725f6e16b29STom Parkin if (tunnel) { 1726fd558d18SJames Chapman BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); 1727fd558d18SJames Chapman if (session->session_id != 0) 1728fd558d18SJames Chapman atomic_dec(&l2tp_session_count); 1729fd558d18SJames Chapman sock_put(tunnel->sock); 1730fd558d18SJames Chapman session->tunnel = NULL; 1731fd558d18SJames Chapman l2tp_tunnel_dec_refcount(tunnel); 1732fd558d18SJames Chapman } 1733fd558d18SJames Chapman 1734fd558d18SJames Chapman kfree(session); 1735fd558d18SJames Chapman 1736fd558d18SJames Chapman return; 1737fd558d18SJames Chapman } 1738fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_session_free); 1739fd558d18SJames Chapman 1740f6e16b29STom Parkin /* Remove an l2tp session from l2tp_core's hash lists. 1741f6e16b29STom Parkin * Provides a tidyup interface for pseudowire code which can't just route all 1742f6e16b29STom Parkin * shutdown via. l2tp_session_delete and a pseudowire-specific session_close 1743f6e16b29STom Parkin * callback. 1744f6e16b29STom Parkin */ 1745f6e16b29STom Parkin void __l2tp_session_unhash(struct l2tp_session *session) 1746f6e16b29STom Parkin { 1747f6e16b29STom Parkin struct l2tp_tunnel *tunnel = session->tunnel; 1748f6e16b29STom Parkin 1749f6e16b29STom Parkin /* Remove the session from core hashes */ 1750f6e16b29STom Parkin if (tunnel) { 1751f6e16b29STom Parkin /* Remove from the per-tunnel hash */ 1752f6e16b29STom Parkin write_lock_bh(&tunnel->hlist_lock); 1753f6e16b29STom Parkin hlist_del_init(&session->hlist); 1754f6e16b29STom Parkin write_unlock_bh(&tunnel->hlist_lock); 1755f6e16b29STom Parkin 1756f6e16b29STom Parkin /* For L2TPv3 we have a per-net hash: remove from there, too */ 1757f6e16b29STom Parkin if (tunnel->version != L2TP_HDR_VER_2) { 1758f6e16b29STom Parkin struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); 1759f6e16b29STom Parkin spin_lock_bh(&pn->l2tp_session_hlist_lock); 1760f6e16b29STom Parkin hlist_del_init_rcu(&session->global_hlist); 1761f6e16b29STom Parkin spin_unlock_bh(&pn->l2tp_session_hlist_lock); 1762f6e16b29STom Parkin synchronize_rcu(); 1763f6e16b29STom Parkin } 1764f6e16b29STom Parkin } 1765f6e16b29STom Parkin } 1766f6e16b29STom Parkin EXPORT_SYMBOL_GPL(__l2tp_session_unhash); 1767f6e16b29STom Parkin 1768309795f4SJames Chapman /* This function is used by the netlink SESSION_DELETE command and by 1769309795f4SJames Chapman pseudowire modules. 1770309795f4SJames Chapman */ 1771309795f4SJames Chapman int l2tp_session_delete(struct l2tp_session *session) 1772309795f4SJames Chapman { 1773f6e16b29STom Parkin if (session->ref) 1774f6e16b29STom Parkin (*session->ref)(session); 1775f6e16b29STom Parkin __l2tp_session_unhash(session); 17764c6e2fd3STom Parkin l2tp_session_queue_purge(session); 1777309795f4SJames Chapman if (session->session_close != NULL) 1778309795f4SJames Chapman (*session->session_close)(session); 1779f6e16b29STom Parkin if (session->deref) 17801b7c92b9SDan Carpenter (*session->deref)(session); 1781309795f4SJames Chapman l2tp_session_dec_refcount(session); 1782309795f4SJames Chapman return 0; 1783309795f4SJames Chapman } 1784309795f4SJames Chapman EXPORT_SYMBOL_GPL(l2tp_session_delete); 1785309795f4SJames Chapman 1786f7faffa3SJames Chapman /* We come here whenever a session's send_seq, cookie_len or 1787f7faffa3SJames Chapman * l2specific_len parameters are set. 1788f7faffa3SJames Chapman */ 1789fc130840Sstephen hemminger static void l2tp_session_set_header_len(struct l2tp_session *session, int version) 1790f7faffa3SJames Chapman { 1791f7faffa3SJames Chapman if (version == L2TP_HDR_VER_2) { 1792f7faffa3SJames Chapman session->hdr_len = 6; 1793f7faffa3SJames Chapman if (session->send_seq) 1794f7faffa3SJames Chapman session->hdr_len += 4; 1795f7faffa3SJames Chapman } else { 17960d76751fSJames Chapman session->hdr_len = 4 + session->cookie_len + session->l2specific_len + session->offset; 17970d76751fSJames Chapman if (session->tunnel->encap == L2TP_ENCAPTYPE_UDP) 17980d76751fSJames Chapman session->hdr_len += 4; 1799f7faffa3SJames Chapman } 1800f7faffa3SJames Chapman 1801f7faffa3SJames Chapman } 1802f7faffa3SJames Chapman 1803fd558d18SJames 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) 1804fd558d18SJames Chapman { 1805fd558d18SJames Chapman struct l2tp_session *session; 1806fd558d18SJames Chapman 1807fd558d18SJames Chapman session = kzalloc(sizeof(struct l2tp_session) + priv_size, GFP_KERNEL); 1808fd558d18SJames Chapman if (session != NULL) { 1809fd558d18SJames Chapman session->magic = L2TP_SESSION_MAGIC; 1810fd558d18SJames Chapman session->tunnel = tunnel; 1811fd558d18SJames Chapman 1812fd558d18SJames Chapman session->session_id = session_id; 1813fd558d18SJames Chapman session->peer_session_id = peer_session_id; 1814d301e325SJames Chapman session->nr = 0; 1815fd558d18SJames Chapman 1816fd558d18SJames Chapman sprintf(&session->name[0], "sess %u/%u", 1817fd558d18SJames Chapman tunnel->tunnel_id, session->session_id); 1818fd558d18SJames Chapman 1819fd558d18SJames Chapman skb_queue_head_init(&session->reorder_q); 1820fd558d18SJames Chapman 1821fd558d18SJames Chapman INIT_HLIST_NODE(&session->hlist); 1822f7faffa3SJames Chapman INIT_HLIST_NODE(&session->global_hlist); 1823fd558d18SJames Chapman 1824fd558d18SJames Chapman /* Inherit debug options from tunnel */ 1825fd558d18SJames Chapman session->debug = tunnel->debug; 1826fd558d18SJames Chapman 1827fd558d18SJames Chapman if (cfg) { 1828f7faffa3SJames Chapman session->pwtype = cfg->pw_type; 1829fd558d18SJames Chapman session->debug = cfg->debug; 1830fd558d18SJames Chapman session->mtu = cfg->mtu; 1831fd558d18SJames Chapman session->mru = cfg->mru; 1832fd558d18SJames Chapman session->send_seq = cfg->send_seq; 1833fd558d18SJames Chapman session->recv_seq = cfg->recv_seq; 1834fd558d18SJames Chapman session->lns_mode = cfg->lns_mode; 1835f7faffa3SJames Chapman session->reorder_timeout = cfg->reorder_timeout; 1836f7faffa3SJames Chapman session->offset = cfg->offset; 1837f7faffa3SJames Chapman session->l2specific_type = cfg->l2specific_type; 1838f7faffa3SJames Chapman session->l2specific_len = cfg->l2specific_len; 1839f7faffa3SJames Chapman session->cookie_len = cfg->cookie_len; 1840f7faffa3SJames Chapman memcpy(&session->cookie[0], &cfg->cookie[0], cfg->cookie_len); 1841f7faffa3SJames Chapman session->peer_cookie_len = cfg->peer_cookie_len; 1842f7faffa3SJames Chapman memcpy(&session->peer_cookie[0], &cfg->peer_cookie[0], cfg->peer_cookie_len); 1843fd558d18SJames Chapman } 1844fd558d18SJames Chapman 1845f7faffa3SJames Chapman if (tunnel->version == L2TP_HDR_VER_2) 1846f7faffa3SJames Chapman session->build_header = l2tp_build_l2tpv2_header; 1847f7faffa3SJames Chapman else 1848f7faffa3SJames Chapman session->build_header = l2tp_build_l2tpv3_header; 1849f7faffa3SJames Chapman 1850f7faffa3SJames Chapman l2tp_session_set_header_len(session, tunnel->version); 1851f7faffa3SJames Chapman 1852fd558d18SJames Chapman /* Bump the reference count. The session context is deleted 1853fd558d18SJames Chapman * only when this drops to zero. 1854fd558d18SJames Chapman */ 1855fd558d18SJames Chapman l2tp_session_inc_refcount(session); 1856fd558d18SJames Chapman l2tp_tunnel_inc_refcount(tunnel); 1857fd558d18SJames Chapman 1858fd558d18SJames Chapman /* Ensure tunnel socket isn't deleted */ 1859fd558d18SJames Chapman sock_hold(tunnel->sock); 1860fd558d18SJames Chapman 1861fd558d18SJames Chapman /* Add session to the tunnel's hash list */ 1862fd558d18SJames Chapman write_lock_bh(&tunnel->hlist_lock); 1863fd558d18SJames Chapman hlist_add_head(&session->hlist, 1864fd558d18SJames Chapman l2tp_session_id_hash(tunnel, session_id)); 1865fd558d18SJames Chapman write_unlock_bh(&tunnel->hlist_lock); 1866fd558d18SJames Chapman 1867f7faffa3SJames Chapman /* And to the global session list if L2TPv3 */ 1868f7faffa3SJames Chapman if (tunnel->version != L2TP_HDR_VER_2) { 1869f7faffa3SJames Chapman struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); 1870f7faffa3SJames Chapman 1871e02d494dSJames Chapman spin_lock_bh(&pn->l2tp_session_hlist_lock); 1872e02d494dSJames Chapman hlist_add_head_rcu(&session->global_hlist, 1873f7faffa3SJames Chapman l2tp_session_id_hash_2(pn, session_id)); 1874e02d494dSJames Chapman spin_unlock_bh(&pn->l2tp_session_hlist_lock); 1875f7faffa3SJames Chapman } 1876f7faffa3SJames Chapman 1877fd558d18SJames Chapman /* Ignore management session in session count value */ 1878fd558d18SJames Chapman if (session->session_id != 0) 1879fd558d18SJames Chapman atomic_inc(&l2tp_session_count); 1880fd558d18SJames Chapman } 1881fd558d18SJames Chapman 1882fd558d18SJames Chapman return session; 1883fd558d18SJames Chapman } 1884fd558d18SJames Chapman EXPORT_SYMBOL_GPL(l2tp_session_create); 1885fd558d18SJames Chapman 1886fd558d18SJames Chapman /***************************************************************************** 1887fd558d18SJames Chapman * Init and cleanup 1888fd558d18SJames Chapman *****************************************************************************/ 1889fd558d18SJames Chapman 1890fd558d18SJames Chapman static __net_init int l2tp_init_net(struct net *net) 1891fd558d18SJames Chapman { 1892e773aaffSJiri Pirko struct l2tp_net *pn = net_generic(net, l2tp_net_id); 1893f7faffa3SJames Chapman int hash; 1894fd558d18SJames Chapman 1895fd558d18SJames Chapman INIT_LIST_HEAD(&pn->l2tp_tunnel_list); 1896e02d494dSJames Chapman spin_lock_init(&pn->l2tp_tunnel_list_lock); 1897fd558d18SJames Chapman 1898f7faffa3SJames Chapman for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) 1899f7faffa3SJames Chapman INIT_HLIST_HEAD(&pn->l2tp_session_hlist[hash]); 1900f7faffa3SJames Chapman 1901e02d494dSJames Chapman spin_lock_init(&pn->l2tp_session_hlist_lock); 1902f7faffa3SJames Chapman 1903fd558d18SJames Chapman return 0; 1904fd558d18SJames Chapman } 1905fd558d18SJames Chapman 1906167eb17eSTom Parkin static __net_exit void l2tp_exit_net(struct net *net) 1907167eb17eSTom Parkin { 1908167eb17eSTom Parkin struct l2tp_net *pn = l2tp_pernet(net); 1909167eb17eSTom Parkin struct l2tp_tunnel *tunnel = NULL; 1910167eb17eSTom Parkin 1911167eb17eSTom Parkin rcu_read_lock_bh(); 1912167eb17eSTom Parkin list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { 1913167eb17eSTom Parkin (void)l2tp_tunnel_delete(tunnel); 1914167eb17eSTom Parkin } 1915167eb17eSTom Parkin rcu_read_unlock_bh(); 1916167eb17eSTom Parkin } 1917167eb17eSTom Parkin 1918fd558d18SJames Chapman static struct pernet_operations l2tp_net_ops = { 1919fd558d18SJames Chapman .init = l2tp_init_net, 1920167eb17eSTom Parkin .exit = l2tp_exit_net, 1921fd558d18SJames Chapman .id = &l2tp_net_id, 1922fd558d18SJames Chapman .size = sizeof(struct l2tp_net), 1923fd558d18SJames Chapman }; 1924fd558d18SJames Chapman 1925fd558d18SJames Chapman static int __init l2tp_init(void) 1926fd558d18SJames Chapman { 1927fd558d18SJames Chapman int rc = 0; 1928fd558d18SJames Chapman 1929fd558d18SJames Chapman rc = register_pernet_device(&l2tp_net_ops); 1930fd558d18SJames Chapman if (rc) 1931fd558d18SJames Chapman goto out; 1932fd558d18SJames Chapman 1933f8ccac0eSTom Parkin l2tp_wq = alloc_workqueue("l2tp", WQ_NON_REENTRANT | WQ_UNBOUND, 0); 1934f8ccac0eSTom Parkin if (!l2tp_wq) { 1935f8ccac0eSTom Parkin pr_err("alloc_workqueue failed\n"); 1936f8ccac0eSTom Parkin rc = -ENOMEM; 1937f8ccac0eSTom Parkin goto out; 1938f8ccac0eSTom Parkin } 1939f8ccac0eSTom Parkin 1940a4ca44faSJoe Perches pr_info("L2TP core driver, %s\n", L2TP_DRV_VERSION); 1941fd558d18SJames Chapman 1942fd558d18SJames Chapman out: 1943fd558d18SJames Chapman return rc; 1944fd558d18SJames Chapman } 1945fd558d18SJames Chapman 1946fd558d18SJames Chapman static void __exit l2tp_exit(void) 1947fd558d18SJames Chapman { 1948fd558d18SJames Chapman unregister_pernet_device(&l2tp_net_ops); 1949f8ccac0eSTom Parkin if (l2tp_wq) { 1950f8ccac0eSTom Parkin destroy_workqueue(l2tp_wq); 1951f8ccac0eSTom Parkin l2tp_wq = NULL; 1952f8ccac0eSTom Parkin } 1953fd558d18SJames Chapman } 1954fd558d18SJames Chapman 1955fd558d18SJames Chapman module_init(l2tp_init); 1956fd558d18SJames Chapman module_exit(l2tp_exit); 1957fd558d18SJames Chapman 1958fd558d18SJames Chapman MODULE_AUTHOR("James Chapman <jchapman@katalix.com>"); 1959fd558d18SJames Chapman MODULE_DESCRIPTION("L2TP core"); 1960fd558d18SJames Chapman MODULE_LICENSE("GPL"); 1961fd558d18SJames Chapman MODULE_VERSION(L2TP_DRV_VERSION); 1962fd558d18SJames Chapman 1963