Commit | Line | Data |
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fd558d18 JC |
1 | /* |
2 | * L2TP internal definitions. | |
3 | * | |
4 | * Copyright (c) 2008,2009 Katalix Systems Ltd | |
5 | * | |
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. | |
9 | */ | |
10 | ||
11 | #ifndef _L2TP_CORE_H_ | |
12 | #define _L2TP_CORE_H_ | |
13 | ||
14 | /* Just some random numbers */ | |
15 | #define L2TP_TUNNEL_MAGIC 0x42114DDA | |
16 | #define L2TP_SESSION_MAGIC 0x0C04EB7D | |
17 | ||
f7faffa3 | 18 | /* Per tunnel, session hash table size */ |
fd558d18 JC |
19 | #define L2TP_HASH_BITS 4 |
20 | #define L2TP_HASH_SIZE (1 << L2TP_HASH_BITS) | |
21 | ||
f7faffa3 JC |
22 | /* System-wide, session hash table size */ |
23 | #define L2TP_HASH_BITS_2 8 | |
24 | #define L2TP_HASH_SIZE_2 (1 << L2TP_HASH_BITS_2) | |
25 | ||
fd558d18 JC |
26 | /* Debug message categories for the DEBUG socket option */ |
27 | enum { | |
28 | L2TP_MSG_DEBUG = (1 << 0), /* verbose debug (if | |
29 | * compiled in) */ | |
30 | L2TP_MSG_CONTROL = (1 << 1), /* userspace - kernel | |
31 | * interface */ | |
32 | L2TP_MSG_SEQ = (1 << 2), /* sequence numbers */ | |
33 | L2TP_MSG_DATA = (1 << 3), /* data packets */ | |
34 | }; | |
35 | ||
36 | struct sk_buff; | |
37 | ||
38 | struct l2tp_stats { | |
39 | u64 tx_packets; | |
40 | u64 tx_bytes; | |
41 | u64 tx_errors; | |
42 | u64 rx_packets; | |
43 | u64 rx_bytes; | |
44 | u64 rx_seq_discards; | |
45 | u64 rx_oos_packets; | |
46 | u64 rx_errors; | |
f7faffa3 | 47 | u64 rx_cookie_discards; |
5de7aee5 | 48 | struct u64_stats_sync syncp; |
fd558d18 JC |
49 | }; |
50 | ||
51 | struct l2tp_tunnel; | |
52 | ||
53 | /* Describes a session. Contains information to determine incoming | |
54 | * packets and transmit outgoing ones. | |
55 | */ | |
56 | struct l2tp_session_cfg { | |
f7faffa3 | 57 | enum l2tp_pwtype pw_type; |
95c96174 | 58 | unsigned int data_seq:2; /* data sequencing level |
fd558d18 JC |
59 | * 0 => none, 1 => IP only, |
60 | * 2 => all | |
61 | */ | |
95c96174 | 62 | unsigned int recv_seq:1; /* expect receive packets with |
fd558d18 | 63 | * sequence numbers? */ |
95c96174 | 64 | unsigned int send_seq:1; /* send packets with sequence |
fd558d18 | 65 | * numbers? */ |
95c96174 | 66 | unsigned int lns_mode:1; /* behave as LNS? LAC enables |
fd558d18 JC |
67 | * sequence numbers under |
68 | * control of LNS. */ | |
69 | int debug; /* bitmask of debug message | |
70 | * categories */ | |
309795f4 | 71 | u16 vlan_id; /* VLAN pseudowire only */ |
f7faffa3 JC |
72 | u16 offset; /* offset to payload */ |
73 | u16 l2specific_len; /* Layer 2 specific length */ | |
74 | u16 l2specific_type; /* Layer 2 specific type */ | |
75 | u8 cookie[8]; /* optional cookie */ | |
76 | int cookie_len; /* 0, 4 or 8 bytes */ | |
77 | u8 peer_cookie[8]; /* peer's cookie */ | |
78 | int peer_cookie_len; /* 0, 4 or 8 bytes */ | |
fd558d18 JC |
79 | int reorder_timeout; /* configured reorder timeout |
80 | * (in jiffies) */ | |
81 | int mtu; | |
82 | int mru; | |
309795f4 | 83 | char *ifname; |
fd558d18 JC |
84 | }; |
85 | ||
86 | struct l2tp_session { | |
87 | int magic; /* should be | |
88 | * L2TP_SESSION_MAGIC */ | |
89 | ||
90 | struct l2tp_tunnel *tunnel; /* back pointer to tunnel | |
91 | * context */ | |
92 | u32 session_id; | |
93 | u32 peer_session_id; | |
f7faffa3 JC |
94 | u8 cookie[8]; |
95 | int cookie_len; | |
96 | u8 peer_cookie[8]; | |
97 | int peer_cookie_len; | |
98 | u16 offset; /* offset from end of L2TP header | |
99 | to beginning of data */ | |
100 | u16 l2specific_len; | |
101 | u16 l2specific_type; | |
102 | u16 hdr_len; | |
103 | u32 nr; /* session NR state (receive) */ | |
104 | u32 ns; /* session NR state (send) */ | |
fd558d18 JC |
105 | struct sk_buff_head reorder_q; /* receive reorder queue */ |
106 | struct hlist_node hlist; /* Hash list node */ | |
107 | atomic_t ref_count; | |
108 | ||
109 | char name[32]; /* for logging */ | |
309795f4 | 110 | char ifname[IFNAMSIZ]; |
95c96174 | 111 | unsigned int data_seq:2; /* data sequencing level |
fd558d18 JC |
112 | * 0 => none, 1 => IP only, |
113 | * 2 => all | |
114 | */ | |
95c96174 | 115 | unsigned int recv_seq:1; /* expect receive packets with |
fd558d18 | 116 | * sequence numbers? */ |
95c96174 | 117 | unsigned int send_seq:1; /* send packets with sequence |
fd558d18 | 118 | * numbers? */ |
95c96174 | 119 | unsigned int lns_mode:1; /* behave as LNS? LAC enables |
fd558d18 JC |
120 | * sequence numbers under |
121 | * control of LNS. */ | |
122 | int debug; /* bitmask of debug message | |
123 | * categories */ | |
124 | int reorder_timeout; /* configured reorder timeout | |
125 | * (in jiffies) */ | |
38d40b3f | 126 | int reorder_skip; /* set if skip to next nr */ |
fd558d18 JC |
127 | int mtu; |
128 | int mru; | |
f7faffa3 | 129 | enum l2tp_pwtype pwtype; |
fd558d18 | 130 | struct l2tp_stats stats; |
f7faffa3 | 131 | struct hlist_node global_hlist; /* Global hash list node */ |
fd558d18 | 132 | |
f7faffa3 | 133 | int (*build_header)(struct l2tp_session *session, void *buf); |
fd558d18 JC |
134 | void (*recv_skb)(struct l2tp_session *session, struct sk_buff *skb, int data_len); |
135 | void (*session_close)(struct l2tp_session *session); | |
136 | void (*ref)(struct l2tp_session *session); | |
137 | void (*deref)(struct l2tp_session *session); | |
f66ef2d0 | 138 | #if defined(CONFIG_L2TP_DEBUGFS) || defined(CONFIG_L2TP_DEBUGFS_MODULE) |
0ad66140 JC |
139 | void (*show)(struct seq_file *m, void *priv); |
140 | #endif | |
fd558d18 JC |
141 | uint8_t priv[0]; /* private data */ |
142 | }; | |
143 | ||
144 | /* Describes the tunnel. It contains info to track all the associated | |
145 | * sessions so incoming packets can be sorted out | |
146 | */ | |
147 | struct l2tp_tunnel_cfg { | |
148 | int debug; /* bitmask of debug message | |
149 | * categories */ | |
0d76751f | 150 | enum l2tp_encap_type encap; |
789a4a2c JC |
151 | |
152 | /* Used only for kernel-created sockets */ | |
153 | struct in_addr local_ip; | |
154 | struct in_addr peer_ip; | |
f9bac8df CE |
155 | #if IS_ENABLED(CONFIG_IPV6) |
156 | struct in6_addr *local_ip6; | |
157 | struct in6_addr *peer_ip6; | |
158 | #endif | |
789a4a2c JC |
159 | u16 local_udp_port; |
160 | u16 peer_udp_port; | |
7bddd0db | 161 | unsigned int use_udp_checksums:1; |
fd558d18 JC |
162 | }; |
163 | ||
164 | struct l2tp_tunnel { | |
165 | int magic; /* Should be L2TP_TUNNEL_MAGIC */ | |
166 | rwlock_t hlist_lock; /* protect session_hlist */ | |
167 | struct hlist_head session_hlist[L2TP_HASH_SIZE]; | |
168 | /* hashed list of sessions, | |
169 | * hashed by id */ | |
170 | u32 tunnel_id; | |
171 | u32 peer_tunnel_id; | |
172 | int version; /* 2=>L2TPv2, 3=>L2TPv3 */ | |
173 | ||
174 | char name[20]; /* for logging */ | |
175 | int debug; /* bitmask of debug message | |
176 | * categories */ | |
0d76751f | 177 | enum l2tp_encap_type encap; |
fd558d18 JC |
178 | struct l2tp_stats stats; |
179 | ||
180 | struct list_head list; /* Keep a list of all tunnels */ | |
181 | struct net *l2tp_net; /* the net we belong to */ | |
182 | ||
183 | atomic_t ref_count; | |
0ad66140 JC |
184 | #ifdef CONFIG_DEBUG_FS |
185 | void (*show)(struct seq_file *m, void *arg); | |
186 | #endif | |
fd558d18 JC |
187 | int (*recv_payload_hook)(struct sk_buff *skb); |
188 | void (*old_sk_destruct)(struct sock *); | |
189 | struct sock *sock; /* Parent socket */ | |
190 | int fd; | |
191 | ||
192 | uint8_t priv[0]; /* private data */ | |
193 | }; | |
194 | ||
309795f4 JC |
195 | struct l2tp_nl_cmd_ops { |
196 | int (*session_create)(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg); | |
197 | int (*session_delete)(struct l2tp_session *session); | |
198 | }; | |
199 | ||
fd558d18 JC |
200 | static inline void *l2tp_tunnel_priv(struct l2tp_tunnel *tunnel) |
201 | { | |
202 | return &tunnel->priv[0]; | |
203 | } | |
204 | ||
205 | static inline void *l2tp_session_priv(struct l2tp_session *session) | |
206 | { | |
207 | return &session->priv[0]; | |
208 | } | |
209 | ||
210 | static inline struct l2tp_tunnel *l2tp_sock_to_tunnel(struct sock *sk) | |
211 | { | |
212 | struct l2tp_tunnel *tunnel; | |
213 | ||
214 | if (sk == NULL) | |
215 | return NULL; | |
216 | ||
217 | sock_hold(sk); | |
218 | tunnel = (struct l2tp_tunnel *)(sk->sk_user_data); | |
219 | if (tunnel == NULL) { | |
220 | sock_put(sk); | |
221 | goto out; | |
222 | } | |
223 | ||
224 | BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); | |
225 | ||
226 | out: | |
227 | return tunnel; | |
228 | } | |
229 | ||
f7faffa3 | 230 | extern struct l2tp_session *l2tp_session_find(struct net *net, struct l2tp_tunnel *tunnel, u32 session_id); |
fd558d18 | 231 | extern struct l2tp_session *l2tp_session_find_nth(struct l2tp_tunnel *tunnel, int nth); |
309795f4 | 232 | extern struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname); |
fd558d18 JC |
233 | extern struct l2tp_tunnel *l2tp_tunnel_find(struct net *net, u32 tunnel_id); |
234 | extern struct l2tp_tunnel *l2tp_tunnel_find_nth(struct net *net, int nth); | |
235 | ||
236 | extern 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); | |
309795f4 | 237 | extern int l2tp_tunnel_delete(struct l2tp_tunnel *tunnel); |
fd558d18 | 238 | extern 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); |
309795f4 | 239 | extern int l2tp_session_delete(struct l2tp_session *session); |
fd558d18 | 240 | extern void l2tp_session_free(struct l2tp_session *session); |
f7faffa3 | 241 | extern void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, unsigned char *ptr, unsigned char *optr, u16 hdrflags, int length, int (*payload_hook)(struct sk_buff *skb)); |
fd558d18 JC |
242 | extern int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb); |
243 | ||
fd558d18 | 244 | extern int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len); |
fd558d18 | 245 | |
309795f4 JC |
246 | extern int l2tp_nl_register_ops(enum l2tp_pwtype pw_type, const struct l2tp_nl_cmd_ops *ops); |
247 | extern void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type); | |
248 | ||
fd558d18 JC |
249 | /* Session reference counts. Incremented when code obtains a reference |
250 | * to a session. | |
251 | */ | |
252 | static inline void l2tp_session_inc_refcount_1(struct l2tp_session *session) | |
253 | { | |
254 | atomic_inc(&session->ref_count); | |
255 | } | |
256 | ||
257 | static inline void l2tp_session_dec_refcount_1(struct l2tp_session *session) | |
258 | { | |
259 | if (atomic_dec_and_test(&session->ref_count)) | |
260 | l2tp_session_free(session); | |
261 | } | |
262 | ||
263 | #ifdef L2TP_REFCNT_DEBUG | |
264 | #define l2tp_session_inc_refcount(_s) do { \ | |
265 | printk(KERN_DEBUG "l2tp_session_inc_refcount: %s:%d %s: cnt=%d\n", __func__, __LINE__, (_s)->name, atomic_read(&_s->ref_count)); \ | |
266 | l2tp_session_inc_refcount_1(_s); \ | |
267 | } while (0) | |
268 | #define l2tp_session_dec_refcount(_s) do { \ | |
269 | printk(KERN_DEBUG "l2tp_session_dec_refcount: %s:%d %s: cnt=%d\n", __func__, __LINE__, (_s)->name, atomic_read(&_s->ref_count)); \ | |
270 | l2tp_session_dec_refcount_1(_s); \ | |
271 | } while (0) | |
272 | #else | |
273 | #define l2tp_session_inc_refcount(s) l2tp_session_inc_refcount_1(s) | |
274 | #define l2tp_session_dec_refcount(s) l2tp_session_dec_refcount_1(s) | |
275 | #endif | |
276 | ||
277 | #endif /* _L2TP_CORE_H_ */ |