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12#include <linux/errno.h>
13#include <linux/gfp.h>
14#include <linux/hdlc.h>
15#include <linux/if_arp.h>
16#include <linux/inetdevice.h>
17#include <linux/init.h>
18#include <linux/kernel.h>
19#include <linux/lapb.h>
20#include <linux/module.h>
21#include <linux/pkt_sched.h>
22#include <linux/poll.h>
23#include <linux/rtnetlink.h>
24#include <linux/skbuff.h>
25#include <net/x25device.h>
26
27static int x25_ioctl(struct net_device *dev, struct ifreq *ifr);
28
29
30
31static 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 netdev_err(dev, "out of memory\n");
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
50static void x25_connected(struct net_device *dev, int reason)
51{
52 x25_connect_disconnect(dev, reason, X25_IFACE_CONNECT);
53}
54
55
56
57static void x25_disconnected(struct net_device *dev, int reason)
58{
59 x25_connect_disconnect(dev, reason, X25_IFACE_DISCONNECT);
60}
61
62
63
64static 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 = X25_IFACE_DATA;
75
76 skb->protocol = x25_type_trans(skb, dev);
77 return netif_rx(skb);
78}
79
80
81
82static 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);
86}
87
88
89
90static netdev_tx_t x25_xmit(struct sk_buff *skb, struct net_device *dev)
91{
92 int result;
93
94
95
96 switch (skb->data[0]) {
97 case X25_IFACE_DATA:
98 skb_pull(skb, 1);
99 if ((result = lapb_data_request(dev, skb)) != LAPB_OK)
100 dev_kfree_skb(skb);
101 return NETDEV_TX_OK;
102
103 case X25_IFACE_CONNECT:
104 if ((result = lapb_connect_request(dev))!= LAPB_OK) {
105 if (result == LAPB_CONNECTED)
106
107 x25_connected(dev, 0);
108 else
109 netdev_err(dev, "LAPB connect request failed, error code = %i\n",
110 result);
111 }
112 break;
113
114 case X25_IFACE_DISCONNECT:
115 if ((result = lapb_disconnect_request(dev)) != LAPB_OK) {
116 if (result == LAPB_NOTCONNECTED)
117
118 x25_disconnected(dev, 0);
119 else
120 netdev_err(dev, "LAPB disconnect request failed, error code = %i\n",
121 result);
122 }
123 break;
124
125 default:
126 break;
127 }
128
129 dev_kfree_skb(skb);
130 return NETDEV_TX_OK;
131}
132
133
134
135static int x25_open(struct net_device *dev)
136{
137 int result;
138 static const struct lapb_register_struct cb = {
139 .connect_confirmation = x25_connected,
140 .connect_indication = x25_connected,
141 .disconnect_confirmation = x25_disconnected,
142 .disconnect_indication = x25_disconnected,
143 .data_indication = x25_data_indication,
144 .data_transmit = x25_data_transmit,
145 };
146
147 result = lapb_register(dev, &cb);
148 if (result != LAPB_OK)
149 return result;
150 return 0;
151}
152
153
154
155static void x25_close(struct net_device *dev)
156{
157 lapb_unregister(dev);
158}
159
160
161
162static int x25_rx(struct sk_buff *skb)
163{
164 struct net_device *dev = skb->dev;
165
166 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) {
167 dev->stats.rx_dropped++;
168 return NET_RX_DROP;
169 }
170
171 if (lapb_data_received(dev, skb) == LAPB_OK)
172 return NET_RX_SUCCESS;
173
174 dev->stats.rx_errors++;
175 dev_kfree_skb_any(skb);
176 return NET_RX_DROP;
177}
178
179
180static struct hdlc_proto proto = {
181 .open = x25_open,
182 .close = x25_close,
183 .ioctl = x25_ioctl,
184 .netif_rx = x25_rx,
185 .xmit = x25_xmit,
186 .module = THIS_MODULE,
187};
188
189
190static int x25_ioctl(struct net_device *dev, struct ifreq *ifr)
191{
192 hdlc_device *hdlc = dev_to_hdlc(dev);
193 int result;
194
195 switch (ifr->ifr_settings.type) {
196 case IF_GET_PROTO:
197 if (dev_to_hdlc(dev)->proto != &proto)
198 return -EINVAL;
199 ifr->ifr_settings.type = IF_PROTO_X25;
200 return 0;
201
202 case IF_PROTO_X25:
203 if (!capable(CAP_NET_ADMIN))
204 return -EPERM;
205
206 if (dev->flags & IFF_UP)
207 return -EBUSY;
208
209 result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
210 if (result)
211 return result;
212
213 if ((result = attach_hdlc_protocol(dev, &proto, 0)))
214 return result;
215 dev->type = ARPHRD_X25;
216 netif_dormant_off(dev);
217 return 0;
218 }
219
220 return -EINVAL;
221}
222
223
224static int __init mod_init(void)
225{
226 register_hdlc_protocol(&proto);
227 return 0;
228}
229
230
231
232static void __exit mod_exit(void)
233{
234 unregister_hdlc_protocol(&proto);
235}
236
237
238module_init(mod_init);
239module_exit(mod_exit);
240
241MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
242MODULE_DESCRIPTION("X.25 protocol support for generic HDLC");
243MODULE_LICENSE("GPL v2");
244
