This source file includes following definitions.
- cisco_hard_header
- cisco_keepalive_send
- cisco_type_trans
- cisco_rx
- cisco_timer
- cisco_start
- cisco_stop
- cisco_ioctl
- mod_init
- mod_exit
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9 #include <linux/errno.h>
10 #include <linux/hdlc.h>
11 #include <linux/if_arp.h>
12 #include <linux/inetdevice.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/pkt_sched.h>
17 #include <linux/poll.h>
18 #include <linux/rtnetlink.h>
19 #include <linux/skbuff.h>
20
21 #undef DEBUG_HARD_HEADER
22
23 #define CISCO_MULTICAST 0x8F
24 #define CISCO_UNICAST 0x0F
25 #define CISCO_KEEPALIVE 0x8035
26 #define CISCO_SYS_INFO 0x2000
27 #define CISCO_ADDR_REQ 0
28 #define CISCO_ADDR_REPLY 1
29 #define CISCO_KEEPALIVE_REQ 2
30
31
32 struct hdlc_header {
33 u8 address;
34 u8 control;
35 __be16 protocol;
36 }__packed;
37
38
39 struct cisco_packet {
40 __be32 type;
41 __be32 par1;
42 __be32 par2;
43 __be16 rel;
44 __be32 time;
45 }__packed;
46 #define CISCO_PACKET_LEN 18
47 #define CISCO_BIG_PACKET_LEN 20
48
49
50 struct cisco_state {
51 cisco_proto settings;
52
53 struct timer_list timer;
54 struct net_device *dev;
55 spinlock_t lock;
56 unsigned long last_poll;
57 int up;
58 u32 txseq;
59 u32 rxseq;
60 };
61
62
63 static int cisco_ioctl(struct net_device *dev, struct ifreq *ifr);
64
65
66 static inline struct cisco_state* state(hdlc_device *hdlc)
67 {
68 return (struct cisco_state *)hdlc->state;
69 }
70
71
72 static int cisco_hard_header(struct sk_buff *skb, struct net_device *dev,
73 u16 type, const void *daddr, const void *saddr,
74 unsigned int len)
75 {
76 struct hdlc_header *data;
77 #ifdef DEBUG_HARD_HEADER
78 printk(KERN_DEBUG "%s: cisco_hard_header called\n", dev->name);
79 #endif
80
81 skb_push(skb, sizeof(struct hdlc_header));
82 data = (struct hdlc_header*)skb->data;
83 if (type == CISCO_KEEPALIVE)
84 data->address = CISCO_MULTICAST;
85 else
86 data->address = CISCO_UNICAST;
87 data->control = 0;
88 data->protocol = htons(type);
89
90 return sizeof(struct hdlc_header);
91 }
92
93
94
95 static void cisco_keepalive_send(struct net_device *dev, u32 type,
96 __be32 par1, __be32 par2)
97 {
98 struct sk_buff *skb;
99 struct cisco_packet *data;
100
101 skb = dev_alloc_skb(sizeof(struct hdlc_header) +
102 sizeof(struct cisco_packet));
103 if (!skb) {
104 netdev_warn(dev, "Memory squeeze on cisco_keepalive_send()\n");
105 return;
106 }
107 skb_reserve(skb, 4);
108 cisco_hard_header(skb, dev, CISCO_KEEPALIVE, NULL, NULL, 0);
109 data = (struct cisco_packet*)(skb->data + 4);
110
111 data->type = htonl(type);
112 data->par1 = par1;
113 data->par2 = par2;
114 data->rel = cpu_to_be16(0xFFFF);
115
116 data->time = htonl((jiffies - INITIAL_JIFFIES) * (1000 / HZ));
117
118 skb_put(skb, sizeof(struct cisco_packet));
119 skb->priority = TC_PRIO_CONTROL;
120 skb->dev = dev;
121 skb_reset_network_header(skb);
122
123 dev_queue_xmit(skb);
124 }
125
126
127
128 static __be16 cisco_type_trans(struct sk_buff *skb, struct net_device *dev)
129 {
130 struct hdlc_header *data = (struct hdlc_header*)skb->data;
131
132 if (skb->len < sizeof(struct hdlc_header))
133 return cpu_to_be16(ETH_P_HDLC);
134
135 if (data->address != CISCO_MULTICAST &&
136 data->address != CISCO_UNICAST)
137 return cpu_to_be16(ETH_P_HDLC);
138
139 switch (data->protocol) {
140 case cpu_to_be16(ETH_P_IP):
141 case cpu_to_be16(ETH_P_IPX):
142 case cpu_to_be16(ETH_P_IPV6):
143 skb_pull(skb, sizeof(struct hdlc_header));
144 return data->protocol;
145 default:
146 return cpu_to_be16(ETH_P_HDLC);
147 }
148 }
149
150
151 static int cisco_rx(struct sk_buff *skb)
152 {
153 struct net_device *dev = skb->dev;
154 hdlc_device *hdlc = dev_to_hdlc(dev);
155 struct cisco_state *st = state(hdlc);
156 struct hdlc_header *data = (struct hdlc_header*)skb->data;
157 struct cisco_packet *cisco_data;
158 struct in_device *in_dev;
159 __be32 addr, mask;
160 u32 ack;
161
162 if (skb->len < sizeof(struct hdlc_header))
163 goto rx_error;
164
165 if (data->address != CISCO_MULTICAST &&
166 data->address != CISCO_UNICAST)
167 goto rx_error;
168
169 switch (ntohs(data->protocol)) {
170 case CISCO_SYS_INFO:
171
172 dev_kfree_skb_any(skb);
173 return NET_RX_SUCCESS;
174
175 case CISCO_KEEPALIVE:
176 if ((skb->len != sizeof(struct hdlc_header) +
177 CISCO_PACKET_LEN) &&
178 (skb->len != sizeof(struct hdlc_header) +
179 CISCO_BIG_PACKET_LEN)) {
180 netdev_info(dev, "Invalid length of Cisco control packet (%d bytes)\n",
181 skb->len);
182 goto rx_error;
183 }
184
185 cisco_data = (struct cisco_packet*)(skb->data + sizeof
186 (struct hdlc_header));
187
188 switch (ntohl (cisco_data->type)) {
189 case CISCO_ADDR_REQ:
190 rcu_read_lock();
191 in_dev = __in_dev_get_rcu(dev);
192 addr = 0;
193 mask = ~cpu_to_be32(0);
194
195 if (in_dev != NULL) {
196 const struct in_ifaddr *ifa;
197
198 in_dev_for_each_ifa_rcu(ifa, in_dev) {
199 if (strcmp(dev->name,
200 ifa->ifa_label) == 0) {
201 addr = ifa->ifa_local;
202 mask = ifa->ifa_mask;
203 break;
204 }
205 }
206
207 cisco_keepalive_send(dev, CISCO_ADDR_REPLY,
208 addr, mask);
209 }
210 rcu_read_unlock();
211 dev_kfree_skb_any(skb);
212 return NET_RX_SUCCESS;
213
214 case CISCO_ADDR_REPLY:
215 netdev_info(dev, "Unexpected Cisco IP address reply\n");
216 goto rx_error;
217
218 case CISCO_KEEPALIVE_REQ:
219 spin_lock(&st->lock);
220 st->rxseq = ntohl(cisco_data->par1);
221 ack = ntohl(cisco_data->par2);
222 if (ack && (ack == st->txseq ||
223
224 ack == st->txseq - 1)) {
225 st->last_poll = jiffies;
226 if (!st->up) {
227 u32 sec, min, hrs, days;
228 sec = ntohl(cisco_data->time) / 1000;
229 min = sec / 60; sec -= min * 60;
230 hrs = min / 60; min -= hrs * 60;
231 days = hrs / 24; hrs -= days * 24;
232 netdev_info(dev, "Link up (peer uptime %ud%uh%um%us)\n",
233 days, hrs, min, sec);
234 netif_dormant_off(dev);
235 st->up = 1;
236 }
237 }
238 spin_unlock(&st->lock);
239
240 dev_kfree_skb_any(skb);
241 return NET_RX_SUCCESS;
242 }
243 }
244
245 netdev_info(dev, "Unsupported protocol %x\n", ntohs(data->protocol));
246 dev_kfree_skb_any(skb);
247 return NET_RX_DROP;
248
249 rx_error:
250 dev->stats.rx_errors++;
251 dev_kfree_skb_any(skb);
252 return NET_RX_DROP;
253 }
254
255
256
257 static void cisco_timer(struct timer_list *t)
258 {
259 struct cisco_state *st = from_timer(st, t, timer);
260 struct net_device *dev = st->dev;
261
262 spin_lock(&st->lock);
263 if (st->up &&
264 time_after(jiffies, st->last_poll + st->settings.timeout * HZ)) {
265 st->up = 0;
266 netdev_info(dev, "Link down\n");
267 netif_dormant_on(dev);
268 }
269
270 cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ, htonl(++st->txseq),
271 htonl(st->rxseq));
272 spin_unlock(&st->lock);
273
274 st->timer.expires = jiffies + st->settings.interval * HZ;
275 add_timer(&st->timer);
276 }
277
278
279
280 static void cisco_start(struct net_device *dev)
281 {
282 hdlc_device *hdlc = dev_to_hdlc(dev);
283 struct cisco_state *st = state(hdlc);
284 unsigned long flags;
285
286 spin_lock_irqsave(&st->lock, flags);
287 st->up = st->txseq = st->rxseq = 0;
288 spin_unlock_irqrestore(&st->lock, flags);
289
290 st->dev = dev;
291 timer_setup(&st->timer, cisco_timer, 0);
292 st->timer.expires = jiffies + HZ;
293 add_timer(&st->timer);
294 }
295
296
297
298 static void cisco_stop(struct net_device *dev)
299 {
300 hdlc_device *hdlc = dev_to_hdlc(dev);
301 struct cisco_state *st = state(hdlc);
302 unsigned long flags;
303
304 del_timer_sync(&st->timer);
305
306 spin_lock_irqsave(&st->lock, flags);
307 netif_dormant_on(dev);
308 st->up = st->txseq = 0;
309 spin_unlock_irqrestore(&st->lock, flags);
310 }
311
312
313 static struct hdlc_proto proto = {
314 .start = cisco_start,
315 .stop = cisco_stop,
316 .type_trans = cisco_type_trans,
317 .ioctl = cisco_ioctl,
318 .netif_rx = cisco_rx,
319 .module = THIS_MODULE,
320 };
321
322 static const struct header_ops cisco_header_ops = {
323 .create = cisco_hard_header,
324 };
325
326 static int cisco_ioctl(struct net_device *dev, struct ifreq *ifr)
327 {
328 cisco_proto __user *cisco_s = ifr->ifr_settings.ifs_ifsu.cisco;
329 const size_t size = sizeof(cisco_proto);
330 cisco_proto new_settings;
331 hdlc_device *hdlc = dev_to_hdlc(dev);
332 int result;
333
334 switch (ifr->ifr_settings.type) {
335 case IF_GET_PROTO:
336 if (dev_to_hdlc(dev)->proto != &proto)
337 return -EINVAL;
338 ifr->ifr_settings.type = IF_PROTO_CISCO;
339 if (ifr->ifr_settings.size < size) {
340 ifr->ifr_settings.size = size;
341 return -ENOBUFS;
342 }
343 if (copy_to_user(cisco_s, &state(hdlc)->settings, size))
344 return -EFAULT;
345 return 0;
346
347 case IF_PROTO_CISCO:
348 if (!capable(CAP_NET_ADMIN))
349 return -EPERM;
350
351 if (dev->flags & IFF_UP)
352 return -EBUSY;
353
354 if (copy_from_user(&new_settings, cisco_s, size))
355 return -EFAULT;
356
357 if (new_settings.interval < 1 ||
358 new_settings.timeout < 2)
359 return -EINVAL;
360
361 result = hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
362 if (result)
363 return result;
364
365 result = attach_hdlc_protocol(dev, &proto,
366 sizeof(struct cisco_state));
367 if (result)
368 return result;
369
370 memcpy(&state(hdlc)->settings, &new_settings, size);
371 spin_lock_init(&state(hdlc)->lock);
372 dev->header_ops = &cisco_header_ops;
373 dev->type = ARPHRD_CISCO;
374 call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
375 netif_dormant_on(dev);
376 return 0;
377 }
378
379 return -EINVAL;
380 }
381
382
383 static int __init mod_init(void)
384 {
385 register_hdlc_protocol(&proto);
386 return 0;
387 }
388
389
390
391 static void __exit mod_exit(void)
392 {
393 unregister_hdlc_protocol(&proto);
394 }
395
396
397 module_init(mod_init);
398 module_exit(mod_exit);
399
400 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
401 MODULE_DESCRIPTION("Cisco HDLC protocol support for generic HDLC");
402 MODULE_LICENSE("GPL v2");