Merge branch 'hwmon-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6
[linux-2.6] / drivers / net / wan / hdlc_x25.c
1 /*
2  * Generic HDLC support routines for Linux
3  * X.25 support
4  *
5  * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of version 2 of the GNU General Public License
9  * as published by the Free Software Foundation.
10  */
11
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/poll.h>
16 #include <linux/errno.h>
17 #include <linux/if_arp.h>
18 #include <linux/init.h>
19 #include <linux/skbuff.h>
20 #include <linux/pkt_sched.h>
21 #include <linux/inetdevice.h>
22 #include <linux/lapb.h>
23 #include <linux/rtnetlink.h>
24 #include <linux/hdlc.h>
25
26 #include <net/x25device.h>
27
28 static int x25_ioctl(struct net_device *dev, struct ifreq *ifr);
29
30 /* These functions are callbacks called by LAPB layer */
31
32 static void x25_connect_disconnect(struct net_device *dev, int reason, int code)
33 {
34         struct sk_buff *skb;
35         unsigned char *ptr;
36
37         if ((skb = dev_alloc_skb(1)) == NULL) {
38                 printk(KERN_ERR "%s: out of memory\n", dev->name);
39                 return;
40         }
41
42         ptr = skb_put(skb, 1);
43         *ptr = code;
44
45         skb->protocol = x25_type_trans(skb, dev);
46         netif_rx(skb);
47 }
48
49
50
51 static void x25_connected(struct net_device *dev, int reason)
52 {
53         x25_connect_disconnect(dev, reason, 1);
54 }
55
56
57
58 static void x25_disconnected(struct net_device *dev, int reason)
59 {
60         x25_connect_disconnect(dev, reason, 2);
61 }
62
63
64
65 static int x25_data_indication(struct net_device *dev, struct sk_buff *skb)
66 {
67         unsigned char *ptr;
68
69         skb_push(skb, 1);
70
71         if (skb_cow(skb, 1))
72                 return NET_RX_DROP;
73
74         ptr  = skb->data;
75         *ptr = 0;
76
77         skb->protocol = x25_type_trans(skb, dev);
78         return netif_rx(skb);
79 }
80
81
82
83 static void x25_data_transmit(struct net_device *dev, struct sk_buff *skb)
84 {
85         hdlc_device *hdlc = dev_to_hdlc(dev);
86         hdlc->xmit(skb, dev); /* Ignore return value :-( */
87 }
88
89
90
91 static int x25_xmit(struct sk_buff *skb, struct net_device *dev)
92 {
93         int result;
94
95
96         /* X.25 to LAPB */
97         switch (skb->data[0]) {
98         case 0:         /* Data to be transmitted */
99                 skb_pull(skb, 1);
100                 if ((result = lapb_data_request(dev, skb)) != LAPB_OK)
101                         dev_kfree_skb(skb);
102                 return 0;
103
104         case 1:
105                 if ((result = lapb_connect_request(dev))!= LAPB_OK) {
106                         if (result == LAPB_CONNECTED)
107                                 /* Send connect confirm. msg to level 3 */
108                                 x25_connected(dev, 0);
109                         else
110                                 printk(KERN_ERR "%s: LAPB connect request "
111                                        "failed, error code = %i\n",
112                                        dev->name, result);
113                 }
114                 break;
115
116         case 2:
117                 if ((result = lapb_disconnect_request(dev)) != LAPB_OK) {
118                         if (result == LAPB_NOTCONNECTED)
119                                 /* Send disconnect confirm. msg to level 3 */
120                                 x25_disconnected(dev, 0);
121                         else
122                                 printk(KERN_ERR "%s: LAPB disconnect request "
123                                        "failed, error code = %i\n",
124                                        dev->name, result);
125                 }
126                 break;
127
128         default:                /* to be defined */
129                 break;
130         }
131
132         dev_kfree_skb(skb);
133         return 0;
134 }
135
136
137
138 static int x25_open(struct net_device *dev)
139 {
140         struct lapb_register_struct cb;
141         int result;
142
143         cb.connect_confirmation = x25_connected;
144         cb.connect_indication = x25_connected;
145         cb.disconnect_confirmation = x25_disconnected;
146         cb.disconnect_indication = x25_disconnected;
147         cb.data_indication = x25_data_indication;
148         cb.data_transmit = x25_data_transmit;
149
150         result = lapb_register(dev, &cb);
151         if (result != LAPB_OK)
152                 return result;
153         return 0;
154 }
155
156
157
158 static void x25_close(struct net_device *dev)
159 {
160         lapb_unregister(dev);
161 }
162
163
164
165 static int x25_rx(struct sk_buff *skb)
166 {
167         struct hdlc_device_desc *desc = dev_to_desc(skb->dev);
168
169         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
170                 desc->stats.rx_dropped++;
171                 return NET_RX_DROP;
172         }
173
174         if (lapb_data_received(skb->dev, skb) == LAPB_OK)
175                 return NET_RX_SUCCESS;
176
177         desc->stats.rx_errors++;
178         dev_kfree_skb_any(skb);
179         return NET_RX_DROP;
180 }
181
182
183 static struct hdlc_proto proto = {
184         .open           = x25_open,
185         .close          = x25_close,
186         .ioctl          = x25_ioctl,
187         .module         = THIS_MODULE,
188 };
189
190
191 static int x25_ioctl(struct net_device *dev, struct ifreq *ifr)
192 {
193         hdlc_device *hdlc = dev_to_hdlc(dev);
194         int result;
195
196         switch (ifr->ifr_settings.type) {
197         case IF_GET_PROTO:
198                 if (dev_to_hdlc(dev)->proto != &proto)
199                         return -EINVAL;
200                 ifr->ifr_settings.type = IF_PROTO_X25;
201                 return 0; /* return protocol only, no settable parameters */
202
203         case IF_PROTO_X25:
204                 if(!capable(CAP_NET_ADMIN))
205                         return -EPERM;
206
207                 if(dev->flags & IFF_UP)
208                         return -EBUSY;
209
210                 result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
211                 if (result)
212                         return result;
213
214                 if ((result = attach_hdlc_protocol(dev, &proto,
215                                                    x25_rx, 0)) != 0)
216                         return result;
217                 dev->hard_start_xmit = x25_xmit;
218                 dev->hard_header = NULL;
219                 dev->type = ARPHRD_X25;
220                 dev->addr_len = 0;
221                 netif_dormant_off(dev);
222                 return 0;
223         }
224
225         return -EINVAL;
226 }
227
228
229 static int __init mod_init(void)
230 {
231         register_hdlc_protocol(&proto);
232         return 0;
233 }
234
235
236
237 static void __exit mod_exit(void)
238 {
239         unregister_hdlc_protocol(&proto);
240 }
241
242
243 module_init(mod_init);
244 module_exit(mod_exit);
245
246 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
247 MODULE_DESCRIPTION("X.25 protocol support for generic HDLC");
248 MODULE_LICENSE("GPL v2");