Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-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/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         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
167                 skb->dev->stats.rx_dropped++;
168                 return NET_RX_DROP;
169         }
170
171         if (lapb_data_received(skb->dev, skb) == LAPB_OK)
172                 return NET_RX_SUCCESS;
173
174         skb->dev->stats.rx_errors++;
175         dev_kfree_skb_any(skb);
176         return NET_RX_DROP;
177 }
178
179
180 static struct hdlc_proto proto = {
181         .open           = x25_open,
182         .close          = x25_close,
183         .ioctl          = x25_ioctl,
184         .netif_rx       = x25_rx,
185         .module         = THIS_MODULE,
186 };
187
188
189 static int x25_ioctl(struct net_device *dev, struct ifreq *ifr)
190 {
191         hdlc_device *hdlc = dev_to_hdlc(dev);
192         int result;
193
194         switch (ifr->ifr_settings.type) {
195         case IF_GET_PROTO:
196                 if (dev_to_hdlc(dev)->proto != &proto)
197                         return -EINVAL;
198                 ifr->ifr_settings.type = IF_PROTO_X25;
199                 return 0; /* return protocol only, no settable parameters */
200
201         case IF_PROTO_X25:
202                 if(!capable(CAP_NET_ADMIN))
203                         return -EPERM;
204
205                 if(dev->flags & IFF_UP)
206                         return -EBUSY;
207
208                 result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
209                 if (result)
210                         return result;
211
212                 if ((result = attach_hdlc_protocol(dev, &proto, 0)))
213                         return result;
214                 dev->hard_start_xmit = x25_xmit;
215                 dev->type = ARPHRD_X25;
216                 netif_dormant_off(dev);
217                 return 0;
218         }
219
220         return -EINVAL;
221 }
222
223
224 static int __init mod_init(void)
225 {
226         register_hdlc_protocol(&proto);
227         return 0;
228 }
229
230
231
232 static void __exit mod_exit(void)
233 {
234         unregister_hdlc_protocol(&proto);
235 }
236
237
238 module_init(mod_init);
239 module_exit(mod_exit);
240
241 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
242 MODULE_DESCRIPTION("X.25 protocol support for generic HDLC");
243 MODULE_LICENSE("GPL v2");