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