Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * llc_core.c - Minimum needed routines for sap handling and module init/exit |
| 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/module.h> |
| 16 | #include <linux/interrupt.h> |
| 17 | #include <linux/if_ether.h> |
| 18 | #include <linux/netdevice.h> |
| 19 | #include <linux/slab.h> |
| 20 | #include <linux/string.h> |
| 21 | #include <linux/init.h> |
Eric W. Biederman | 881d966 | 2007-09-17 11:56:21 -0700 | [diff] [blame^] | 22 | #include <net/net_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <net/llc.h> |
| 24 | |
| 25 | LIST_HEAD(llc_sap_list); |
| 26 | DEFINE_RWLOCK(llc_sap_list_lock); |
| 27 | |
| 28 | unsigned char llc_station_mac_sa[ETH_ALEN]; |
| 29 | |
| 30 | /** |
| 31 | * llc_sap_alloc - allocates and initializes sap. |
| 32 | * |
| 33 | * Allocates and initializes sap. |
| 34 | */ |
| 35 | static struct llc_sap *llc_sap_alloc(void) |
| 36 | { |
Panagiotis Issaris | 0da974f | 2006-07-21 14:51:30 -0700 | [diff] [blame] | 37 | struct llc_sap *sap = kzalloc(sizeof(*sap), GFP_ATOMIC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | |
| 39 | if (sap) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | sap->state = LLC_SAP_STATE_ACTIVE; |
| 41 | memcpy(sap->laddr.mac, llc_station_mac_sa, ETH_ALEN); |
| 42 | rwlock_init(&sap->sk_list.lock); |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 43 | atomic_set(&sap->refcnt, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | } |
| 45 | return sap; |
| 46 | } |
| 47 | |
| 48 | /** |
| 49 | * llc_add_sap - add sap to station list |
| 50 | * @sap: Address of the sap |
| 51 | * |
| 52 | * Adds a sap to the LLC's station sap list. |
| 53 | */ |
| 54 | static void llc_add_sap(struct llc_sap *sap) |
| 55 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | list_add_tail(&sap->node, &llc_sap_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | } |
| 58 | |
| 59 | /** |
| 60 | * llc_del_sap - del sap from station list |
| 61 | * @sap: Address of the sap |
| 62 | * |
| 63 | * Removes a sap to the LLC's station sap list. |
| 64 | */ |
| 65 | static void llc_del_sap(struct llc_sap *sap) |
| 66 | { |
| 67 | write_lock_bh(&llc_sap_list_lock); |
| 68 | list_del(&sap->node); |
| 69 | write_unlock_bh(&llc_sap_list_lock); |
| 70 | } |
| 71 | |
Arnaldo Carvalho de Melo | 2928c19 | 2005-09-22 05:14:33 -0300 | [diff] [blame] | 72 | static struct llc_sap *__llc_sap_find(unsigned char sap_value) |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 73 | { |
| 74 | struct llc_sap* sap; |
| 75 | |
| 76 | list_for_each_entry(sap, &llc_sap_list, node) |
| 77 | if (sap->laddr.lsap == sap_value) |
| 78 | goto out; |
| 79 | sap = NULL; |
| 80 | out: |
| 81 | return sap; |
| 82 | } |
| 83 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | /** |
| 85 | * llc_sap_find - searchs a SAP in station |
| 86 | * @sap_value: sap to be found |
| 87 | * |
| 88 | * Searchs for a sap in the sap list of the LLC's station upon the sap ID. |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 89 | * If the sap is found it will be refcounted and the user will have to do |
| 90 | * a llc_sap_put after use. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | * Returns the sap or %NULL if not found. |
| 92 | */ |
| 93 | struct llc_sap *llc_sap_find(unsigned char sap_value) |
| 94 | { |
| 95 | struct llc_sap* sap; |
| 96 | |
| 97 | read_lock_bh(&llc_sap_list_lock); |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 98 | sap = __llc_sap_find(sap_value); |
| 99 | if (sap) |
| 100 | llc_sap_hold(sap); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | read_unlock_bh(&llc_sap_list_lock); |
| 102 | return sap; |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * llc_sap_open - open interface to the upper layers. |
| 107 | * @lsap: SAP number. |
| 108 | * @func: rcv func for datalink protos |
| 109 | * |
| 110 | * Interface function to upper layer. Each one who wants to get a SAP |
| 111 | * (for example NetBEUI) should call this function. Returns the opened |
| 112 | * SAP for success, NULL for failure. |
| 113 | */ |
| 114 | struct llc_sap *llc_sap_open(unsigned char lsap, |
| 115 | int (*func)(struct sk_buff *skb, |
| 116 | struct net_device *dev, |
David S. Miller | f2ccd8f | 2005-08-09 19:34:12 -0700 | [diff] [blame] | 117 | struct packet_type *pt, |
| 118 | struct net_device *orig_dev)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | { |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 120 | struct llc_sap *sap = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 122 | write_lock_bh(&llc_sap_list_lock); |
| 123 | if (__llc_sap_find(lsap)) /* SAP already exists */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | sap = llc_sap_alloc(); |
| 126 | if (!sap) |
| 127 | goto out; |
| 128 | sap->laddr.lsap = lsap; |
| 129 | sap->rcv_func = func; |
| 130 | llc_add_sap(sap); |
| 131 | out: |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 132 | write_unlock_bh(&llc_sap_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | return sap; |
| 134 | } |
| 135 | |
| 136 | /** |
| 137 | * llc_sap_close - close interface for upper layers. |
| 138 | * @sap: SAP to be closed. |
| 139 | * |
| 140 | * Close interface function to upper layer. Each one who wants to |
| 141 | * close an open SAP (for example NetBEUI) should call this function. |
| 142 | * Removes this sap from the list of saps in the station and then |
| 143 | * frees the memory for this sap. |
| 144 | */ |
| 145 | void llc_sap_close(struct llc_sap *sap) |
| 146 | { |
| 147 | WARN_ON(!hlist_empty(&sap->sk_list.list)); |
| 148 | llc_del_sap(sap); |
| 149 | kfree(sap); |
| 150 | } |
| 151 | |
| 152 | static struct packet_type llc_packet_type = { |
| 153 | .type = __constant_htons(ETH_P_802_2), |
| 154 | .func = llc_rcv, |
| 155 | }; |
| 156 | |
| 157 | static struct packet_type llc_tr_packet_type = { |
| 158 | .type = __constant_htons(ETH_P_TR_802_2), |
| 159 | .func = llc_rcv, |
| 160 | }; |
| 161 | |
| 162 | static int __init llc_init(void) |
| 163 | { |
Pavel Emelianov | 7562f87 | 2007-05-03 15:13:45 -0700 | [diff] [blame] | 164 | struct net_device *dev; |
| 165 | |
Eric W. Biederman | 881d966 | 2007-09-17 11:56:21 -0700 | [diff] [blame^] | 166 | dev = first_net_device(&init_net); |
Pavel Emelianov | 7562f87 | 2007-05-03 15:13:45 -0700 | [diff] [blame] | 167 | if (dev != NULL) |
| 168 | dev = next_net_device(dev); |
| 169 | |
| 170 | if (dev != NULL) |
| 171 | memcpy(llc_station_mac_sa, dev->dev_addr, ETH_ALEN); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | else |
| 173 | memset(llc_station_mac_sa, 0, ETH_ALEN); |
| 174 | dev_add_pack(&llc_packet_type); |
| 175 | dev_add_pack(&llc_tr_packet_type); |
| 176 | return 0; |
| 177 | } |
| 178 | |
| 179 | static void __exit llc_exit(void) |
| 180 | { |
| 181 | dev_remove_pack(&llc_packet_type); |
| 182 | dev_remove_pack(&llc_tr_packet_type); |
| 183 | } |
| 184 | |
| 185 | module_init(llc_init); |
| 186 | module_exit(llc_exit); |
| 187 | |
| 188 | EXPORT_SYMBOL(llc_station_mac_sa); |
| 189 | EXPORT_SYMBOL(llc_sap_list); |
| 190 | EXPORT_SYMBOL(llc_sap_list_lock); |
| 191 | EXPORT_SYMBOL(llc_sap_find); |
| 192 | EXPORT_SYMBOL(llc_sap_open); |
| 193 | EXPORT_SYMBOL(llc_sap_close); |
| 194 | |
| 195 | MODULE_LICENSE("GPL"); |
| 196 | MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003"); |
| 197 | MODULE_DESCRIPTION("LLC IEEE 802.2 core support"); |