1#ifndef LLC_H
2#define LLC_H
3/*
4 * Copyright (c) 1997 by Procom Technology, Inc.
5 * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
6 *
7 * This program can be redistributed or modified under the terms of the
8 * GNU General Public License as published by the Free Software Foundation.
9 * This program is distributed without any warranty or implied warranty
10 * of merchantability or fitness for a particular purpose.
11 *
12 * See the GNU General Public License for more details.
13 */
14
15#include <linux/if.h>
16#include <linux/if_ether.h>
17#include <linux/list.h>
18#include <linux/spinlock.h>
19#include <linux/rculist_nulls.h>
20#include <linux/hash.h>
21#include <linux/jhash.h>
22
23#include <linux/atomic.h>
24
25struct net_device;
26struct packet_type;
27struct sk_buff;
28
29struct llc_addr {
30 unsigned char lsap;
31 unsigned char mac[IFHWADDRLEN];
32};
33
34#define LLC_SAP_STATE_INACTIVE 1
35#define LLC_SAP_STATE_ACTIVE 2
36
37#define LLC_SK_DEV_HASH_BITS 6
38#define LLC_SK_DEV_HASH_ENTRIES (1<<LLC_SK_DEV_HASH_BITS)
39
40#define LLC_SK_LADDR_HASH_BITS 6
41#define LLC_SK_LADDR_HASH_ENTRIES (1<<LLC_SK_LADDR_HASH_BITS)
42
43/**
44 * struct llc_sap - Defines the SAP component
45 *
46 * @station - station this sap belongs to
47 * @state - sap state
48 * @p_bit - only lowest-order bit used
49 * @f_bit - only lowest-order bit used
50 * @laddr - SAP value in this 'lsap'
51 * @node - entry in station sap_list
52 * @sk_list - LLC sockets this one manages
53 */
54struct llc_sap {
55 unsigned char state;
56 unsigned char p_bit;
57 unsigned char f_bit;
58 refcount_t refcnt;
59 int (*rcv_func)(struct sk_buff *skb,
60 struct net_device *dev,
61 struct packet_type *pt,
62 struct net_device *orig_dev);
63 struct llc_addr laddr;
64 struct list_head node;
65 spinlock_t sk_lock;
66 int sk_count;
67 struct hlist_nulls_head sk_laddr_hash[LLC_SK_LADDR_HASH_ENTRIES];
68 struct hlist_head sk_dev_hash[LLC_SK_DEV_HASH_ENTRIES];
69 struct rcu_head rcu;
70};
71
72static inline
73struct hlist_head *llc_sk_dev_hash(struct llc_sap *sap, int ifindex)
74{
75 return &sap->sk_dev_hash[ifindex % LLC_SK_DEV_HASH_ENTRIES];
76}
77
78static inline
79u32 llc_sk_laddr_hashfn(struct llc_sap *sap, const struct llc_addr *laddr)
80{
81 return hash_32(jhash(laddr->mac, sizeof(laddr->mac), 0),
82 LLC_SK_LADDR_HASH_BITS);
83}
84
85static inline
86struct hlist_nulls_head *llc_sk_laddr_hash(struct llc_sap *sap,
87 const struct llc_addr *laddr)
88{
89 return &sap->sk_laddr_hash[llc_sk_laddr_hashfn(sap, laddr)];
90}
91
92#define LLC_DEST_INVALID 0 /* Invalid LLC PDU type */
93#define LLC_DEST_SAP 1 /* Type 1 goes here */
94#define LLC_DEST_CONN 2 /* Type 2 goes here */
95
96extern struct list_head llc_sap_list;
97
98int llc_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
99 struct net_device *orig_dev);
100
101int llc_mac_hdr_init(struct sk_buff *skb, const unsigned char *sa,
102 const unsigned char *da);
103
104void llc_add_pack(int type,
105 void (*handler)(struct llc_sap *sap, struct sk_buff *skb));
106void llc_remove_pack(int type);
107
108void llc_set_station_handler(void (*handler)(struct sk_buff *skb));
109
110struct llc_sap *llc_sap_open(unsigned char lsap,
111 int (*rcv)(struct sk_buff *skb,
112 struct net_device *dev,
113 struct packet_type *pt,
114 struct net_device *orig_dev));
115static inline void llc_sap_hold(struct llc_sap *sap)
116{
117 refcount_inc(&sap->refcnt);
118}
119
120static inline bool llc_sap_hold_safe(struct llc_sap *sap)
121{
122 return refcount_inc_not_zero(&sap->refcnt);
123}
124
125void llc_sap_close(struct llc_sap *sap);
126
127static inline void llc_sap_put(struct llc_sap *sap)
128{
129 if (refcount_dec_and_test(&sap->refcnt))
130 llc_sap_close(sap);
131}
132
133struct llc_sap *llc_sap_find(unsigned char sap_value);
134
135int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb,
136 unsigned char *dmac, unsigned char dsap);
137
138void llc_sap_handler(struct llc_sap *sap, struct sk_buff *skb);
139void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb);
140
141void llc_station_init(void);
142void llc_station_exit(void);
143
144#ifdef CONFIG_PROC_FS
145int llc_proc_init(void);
146void llc_proc_exit(void);
147#else
148#define llc_proc_init() (0)
149#define llc_proc_exit() do { } while(0)
150#endif /* CONFIG_PROC_FS */
151#ifdef CONFIG_SYSCTL
152int llc_sysctl_init(void);
153void llc_sysctl_exit(void);
154
155extern int sysctl_llc2_ack_timeout;
156extern int sysctl_llc2_busy_timeout;
157extern int sysctl_llc2_p_timeout;
158extern int sysctl_llc2_rej_timeout;
159#else
160#define llc_sysctl_init() (0)
161#define llc_sysctl_exit() do { } while(0)
162#endif /* CONFIG_SYSCTL */
163#endif /* LLC_H */
164