2 * L2TP internal definitions.
4 * Copyright (c) 2008,2009 Katalix Systems Ltd
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 #include <linux/refcount.h>
15 /* Just some random numbers */
16 #define L2TP_TUNNEL_MAGIC 0x42114DDA
17 #define L2TP_SESSION_MAGIC 0x0C04EB7D
19 /* Per tunnel, session hash table size */
20 #define L2TP_HASH_BITS 4
21 #define L2TP_HASH_SIZE (1 << L2TP_HASH_BITS)
23 /* System-wide, session hash table size */
24 #define L2TP_HASH_BITS_2 8
25 #define L2TP_HASH_SIZE_2 (1 << L2TP_HASH_BITS_2)
30 atomic_long_t tx_packets
;
31 atomic_long_t tx_bytes
;
32 atomic_long_t tx_errors
;
33 atomic_long_t rx_packets
;
34 atomic_long_t rx_bytes
;
35 atomic_long_t rx_seq_discards
;
36 atomic_long_t rx_oos_packets
;
37 atomic_long_t rx_errors
;
38 atomic_long_t rx_cookie_discards
;
43 /* Describes a session. Contains information to determine incoming
44 * packets and transmit outgoing ones.
46 struct l2tp_session_cfg
{
47 enum l2tp_pwtype pw_type
;
48 unsigned int data_seq
:2; /* data sequencing level
49 * 0 => none, 1 => IP only,
52 unsigned int recv_seq
:1; /* expect receive packets with
53 * sequence numbers? */
54 unsigned int send_seq
:1; /* send packets with sequence
56 unsigned int lns_mode
:1; /* behave as LNS? LAC enables
57 * sequence numbers under
59 int debug
; /* bitmask of debug message
61 u16 vlan_id
; /* VLAN pseudowire only */
62 u16 offset
; /* offset to payload */
63 u16 l2specific_len
; /* Layer 2 specific length */
64 u16 l2specific_type
; /* Layer 2 specific type */
65 u8 cookie
[8]; /* optional cookie */
66 int cookie_len
; /* 0, 4 or 8 bytes */
67 u8 peer_cookie
[8]; /* peer's cookie */
68 int peer_cookie_len
; /* 0, 4 or 8 bytes */
69 int reorder_timeout
; /* configured reorder timeout
77 int magic
; /* should be
78 * L2TP_SESSION_MAGIC */
81 struct l2tp_tunnel
*tunnel
; /* back pointer to tunnel
89 u16 offset
; /* offset from end of L2TP header
90 to beginning of data */
94 u32 nr
; /* session NR state (receive) */
95 u32 ns
; /* session NR state (send) */
96 struct sk_buff_head reorder_q
; /* receive reorder queue */
97 u32 nr_max
; /* max NR. Depends on tunnel */
98 u32 nr_window_size
; /* NR window size */
99 u32 nr_oos
; /* NR of last OOS packet */
100 int nr_oos_count
; /* For OOS recovery */
101 int nr_oos_count_max
;
102 struct hlist_node hlist
; /* Hash list node */
103 refcount_t ref_count
;
105 char name
[32]; /* for logging */
106 char ifname
[IFNAMSIZ
];
107 unsigned int data_seq
:2; /* data sequencing level
108 * 0 => none, 1 => IP only,
111 unsigned int recv_seq
:1; /* expect receive packets with
112 * sequence numbers? */
113 unsigned int send_seq
:1; /* send packets with sequence
115 unsigned int lns_mode
:1; /* behave as LNS? LAC enables
116 * sequence numbers under
118 int debug
; /* bitmask of debug message
120 int reorder_timeout
; /* configured reorder timeout
122 int reorder_skip
; /* set if skip to next nr */
125 enum l2tp_pwtype pwtype
;
126 struct l2tp_stats stats
;
127 struct hlist_node global_hlist
; /* Global hash list node */
129 int (*build_header
)(struct l2tp_session
*session
, void *buf
);
130 void (*recv_skb
)(struct l2tp_session
*session
, struct sk_buff
*skb
, int data_len
);
131 void (*session_close
)(struct l2tp_session
*session
);
132 #if IS_ENABLED(CONFIG_L2TP_DEBUGFS)
133 void (*show
)(struct seq_file
*m
, void *priv
);
135 uint8_t priv
[0]; /* private data */
138 /* Describes the tunnel. It contains info to track all the associated
139 * sessions so incoming packets can be sorted out
141 struct l2tp_tunnel_cfg
{
142 int debug
; /* bitmask of debug message
144 enum l2tp_encap_type encap
;
146 /* Used only for kernel-created sockets */
147 struct in_addr local_ip
;
148 struct in_addr peer_ip
;
149 #if IS_ENABLED(CONFIG_IPV6)
150 struct in6_addr
*local_ip6
;
151 struct in6_addr
*peer_ip6
;
155 unsigned int use_udp_checksums
:1,
156 udp6_zero_tx_checksums
:1,
157 udp6_zero_rx_checksums
:1;
161 int magic
; /* Should be L2TP_TUNNEL_MAGIC */
166 rwlock_t hlist_lock
; /* protect session_hlist */
167 bool acpt_newsess
; /* Indicates whether this
168 * tunnel accepts new sessions.
169 * Protected by hlist_lock.
171 struct hlist_head session_hlist
[L2TP_HASH_SIZE
];
172 /* hashed list of sessions,
176 int version
; /* 2=>L2TPv2, 3=>L2TPv3 */
178 char name
[20]; /* for logging */
179 int debug
; /* bitmask of debug message
181 enum l2tp_encap_type encap
;
182 struct l2tp_stats stats
;
184 struct list_head list
; /* Keep a list of all tunnels */
185 struct net
*l2tp_net
; /* the net we belong to */
187 refcount_t ref_count
;
188 #ifdef CONFIG_DEBUG_FS
189 void (*show
)(struct seq_file
*m
, void *arg
);
191 int (*recv_payload_hook
)(struct sk_buff
*skb
);
192 void (*old_sk_destruct
)(struct sock
*);
193 struct sock
*sock
; /* Parent socket */
194 int fd
; /* Parent fd, if tunnel socket
195 * was created by userspace */
196 #if IS_ENABLED(CONFIG_IPV6)
200 struct work_struct del_work
;
202 uint8_t priv
[0]; /* private data */
205 struct l2tp_nl_cmd_ops
{
206 int (*session_create
)(struct net
*net
, struct l2tp_tunnel
*tunnel
,
207 u32 session_id
, u32 peer_session_id
,
208 struct l2tp_session_cfg
*cfg
);
209 int (*session_delete
)(struct l2tp_session
*session
);
212 static inline void *l2tp_tunnel_priv(struct l2tp_tunnel
*tunnel
)
214 return &tunnel
->priv
[0];
217 static inline void *l2tp_session_priv(struct l2tp_session
*session
)
219 return &session
->priv
[0];
222 struct l2tp_tunnel
*l2tp_tunnel_get(const struct net
*net
, u32 tunnel_id
);
223 void l2tp_tunnel_free(struct l2tp_tunnel
*tunnel
);
225 struct l2tp_session
*l2tp_session_get(const struct net
*net
,
226 struct l2tp_tunnel
*tunnel
,
228 struct l2tp_session
*l2tp_session_get_nth(struct l2tp_tunnel
*tunnel
, int nth
);
229 struct l2tp_session
*l2tp_session_get_by_ifname(const struct net
*net
,
231 struct l2tp_tunnel
*l2tp_tunnel_find(const struct net
*net
, u32 tunnel_id
);
232 struct l2tp_tunnel
*l2tp_tunnel_find_nth(const struct net
*net
, int nth
);
234 int l2tp_tunnel_create(struct net
*net
, int fd
, int version
, u32 tunnel_id
,
235 u32 peer_tunnel_id
, struct l2tp_tunnel_cfg
*cfg
,
236 struct l2tp_tunnel
**tunnelp
);
237 void l2tp_tunnel_closeall(struct l2tp_tunnel
*tunnel
);
238 void l2tp_tunnel_delete(struct l2tp_tunnel
*tunnel
);
239 struct l2tp_session
*l2tp_session_create(int priv_size
,
240 struct l2tp_tunnel
*tunnel
,
241 u32 session_id
, u32 peer_session_id
,
242 struct l2tp_session_cfg
*cfg
);
243 int l2tp_session_register(struct l2tp_session
*session
,
244 struct l2tp_tunnel
*tunnel
);
246 void __l2tp_session_unhash(struct l2tp_session
*session
);
247 int l2tp_session_delete(struct l2tp_session
*session
);
248 void l2tp_session_free(struct l2tp_session
*session
);
249 void l2tp_recv_common(struct l2tp_session
*session
, struct sk_buff
*skb
,
250 unsigned char *ptr
, unsigned char *optr
, u16 hdrflags
,
251 int length
, int (*payload_hook
)(struct sk_buff
*skb
));
252 int l2tp_session_queue_purge(struct l2tp_session
*session
);
253 int l2tp_udp_encap_recv(struct sock
*sk
, struct sk_buff
*skb
);
254 void l2tp_session_set_header_len(struct l2tp_session
*session
, int version
);
256 int l2tp_xmit_skb(struct l2tp_session
*session
, struct sk_buff
*skb
,
259 int l2tp_nl_register_ops(enum l2tp_pwtype pw_type
,
260 const struct l2tp_nl_cmd_ops
*ops
);
261 void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type
);
262 int l2tp_ioctl(struct sock
*sk
, int cmd
, unsigned long arg
);
264 static inline void l2tp_tunnel_inc_refcount(struct l2tp_tunnel
*tunnel
)
266 refcount_inc(&tunnel
->ref_count
);
269 static inline void l2tp_tunnel_dec_refcount(struct l2tp_tunnel
*tunnel
)
271 if (refcount_dec_and_test(&tunnel
->ref_count
))
272 l2tp_tunnel_free(tunnel
);
275 /* Session reference counts. Incremented when code obtains a reference
278 static inline void l2tp_session_inc_refcount(struct l2tp_session
*session
)
280 refcount_inc(&session
->ref_count
);
283 static inline void l2tp_session_dec_refcount(struct l2tp_session
*session
)
285 if (refcount_dec_and_test(&session
->ref_count
))
286 l2tp_session_free(session
);
289 #define l2tp_printk(ptr, type, func, fmt, ...) \
291 if (((ptr)->debug) & (type)) \
292 func(fmt, ##__VA_ARGS__); \
295 #define l2tp_warn(ptr, type, fmt, ...) \
296 l2tp_printk(ptr, type, pr_warn, fmt, ##__VA_ARGS__)
297 #define l2tp_info(ptr, type, fmt, ...) \
298 l2tp_printk(ptr, type, pr_info, fmt, ##__VA_ARGS__)
299 #define l2tp_dbg(ptr, type, fmt, ...) \
300 l2tp_printk(ptr, type, pr_debug, fmt, ##__VA_ARGS__)
302 #define MODULE_ALIAS_L2TP_PWTYPE(type) \
303 MODULE_ALIAS("net-l2tp-type-" __stringify(type))
305 #endif /* _L2TP_CORE_H_ */