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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Generic HDLC support routines for Linux
  4 * Cisco HDLC support
  5 *
  6 * Copyright (C) 2000 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
  7 */
  8
  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	/* Cisco multicast address */
 24#define CISCO_UNICAST		0x0F	/* Cisco unicast address */
 25#define CISCO_KEEPALIVE		0x8035	/* Cisco keepalive protocol */
 26#define CISCO_SYS_INFO		0x2000	/* Cisco interface/system info */
 27#define CISCO_ADDR_REQ		0	/* Cisco address request */
 28#define CISCO_ADDR_REPLY	1	/* Cisco address reply */
 29#define CISCO_KEEPALIVE_REQ	2	/* Cisco keepalive request */
 30
 31struct hdlc_header {
 32	u8 address;
 33	u8 control;
 34	__be16 protocol;
 35} __packed;
 36
 37struct cisco_packet {
 38	__be32 type;		/* code */
 39	__be32 par1;
 40	__be32 par2;
 41	__be16 rel;		/* reliability */
 42	__be32 time;
 43} __packed;
 44#define	CISCO_PACKET_LEN	18
 45#define	CISCO_BIG_PACKET_LEN	20
 46
 47struct cisco_state {
 48	cisco_proto settings;
 49
 50	struct timer_list timer;
 51	struct net_device *dev;
 52	spinlock_t lock;
 53	unsigned long last_poll;
 54	int up;
 55	u32 txseq; /* TX sequence number, 0 = none */
 56	u32 rxseq; /* RX sequence number */
 57};
 58
 59static int cisco_ioctl(struct net_device *dev, struct if_settings *ifs);
 60
 61static inline struct cisco_state *state(hdlc_device *hdlc)
 62{
 63	return (struct cisco_state *)hdlc->state;
 64}
 65
 66static int cisco_hard_header(struct sk_buff *skb, struct net_device *dev,
 67			     u16 type, const void *daddr, const void *saddr,
 68			     unsigned int len)
 69{
 70	struct hdlc_header *data;
 71#ifdef DEBUG_HARD_HEADER
 72	netdev_dbg(dev, "%s called\n", __func__);
 73#endif
 74
 75	skb_push(skb, sizeof(struct hdlc_header));
 76	data = (struct hdlc_header *)skb->data;
 77	if (type == CISCO_KEEPALIVE)
 78		data->address = CISCO_MULTICAST;
 79	else
 80		data->address = CISCO_UNICAST;
 81	data->control = 0;
 82	data->protocol = htons(type);
 83
 84	return sizeof(struct hdlc_header);
 85}
 86
 87static void cisco_keepalive_send(struct net_device *dev, u32 type,
 88				 __be32 par1, __be32 par2)
 89{
 90	struct sk_buff *skb;
 91	struct cisco_packet *data;
 92
 93	skb = dev_alloc_skb(sizeof(struct hdlc_header) +
 94			    sizeof(struct cisco_packet));
 95	if (!skb)
 96		return;
 97
 98	skb_reserve(skb, 4);
 99	cisco_hard_header(skb, dev, CISCO_KEEPALIVE, NULL, NULL, 0);
100	data = (struct cisco_packet *)(skb->data + 4);
101
102	data->type = htonl(type);
103	data->par1 = par1;
104	data->par2 = par2;
105	data->rel = cpu_to_be16(0xFFFF);
106	/* we will need do_div here if 1000 % HZ != 0 */
107	data->time = htonl((jiffies - INITIAL_JIFFIES) * (1000 / HZ));
108
109	skb_put(skb, sizeof(struct cisco_packet));
110	skb->priority = TC_PRIO_CONTROL;
111	skb->dev = dev;
112	skb->protocol = htons(ETH_P_HDLC);
113	skb_reset_network_header(skb);
114
115	dev_queue_xmit(skb);
116}
117
118static __be16 cisco_type_trans(struct sk_buff *skb, struct net_device *dev)
119{
120	struct hdlc_header *data = (struct hdlc_header *)skb->data;
121
122	if (skb->len < sizeof(struct hdlc_header))
123		return cpu_to_be16(ETH_P_HDLC);
124
125	if (data->address != CISCO_MULTICAST &&
126	    data->address != CISCO_UNICAST)
127		return cpu_to_be16(ETH_P_HDLC);
128
129	switch (data->protocol) {
130	case cpu_to_be16(ETH_P_IP):
131	case cpu_to_be16(ETH_P_IPX):
132	case cpu_to_be16(ETH_P_IPV6):
133		skb_pull(skb, sizeof(struct hdlc_header));
134		return data->protocol;
135	default:
136		return cpu_to_be16(ETH_P_HDLC);
137	}
138}
139
140static int cisco_rx(struct sk_buff *skb)
141{
142	struct net_device *dev = skb->dev;
143	hdlc_device *hdlc = dev_to_hdlc(dev);
144	struct cisco_state *st = state(hdlc);
145	struct hdlc_header *data = (struct hdlc_header *)skb->data;
146	struct cisco_packet *cisco_data;
147	struct in_device *in_dev;
148	__be32 addr, mask;
149	u32 ack;
150
151	if (skb->len < sizeof(struct hdlc_header))
152		goto rx_error;
153
154	if (data->address != CISCO_MULTICAST &&
155	    data->address != CISCO_UNICAST)
156		goto rx_error;
157
158	switch (ntohs(data->protocol)) {
159	case CISCO_SYS_INFO:
160		/* Packet is not needed, drop it. */
161		dev_kfree_skb_any(skb);
162		return NET_RX_SUCCESS;
163
164	case CISCO_KEEPALIVE:
165		if ((skb->len != sizeof(struct hdlc_header) +
166		     CISCO_PACKET_LEN) &&
167		    (skb->len != sizeof(struct hdlc_header) +
168		     CISCO_BIG_PACKET_LEN)) {
169			netdev_info(dev, "Invalid length of Cisco control packet (%d bytes)\n",
170				    skb->len);
171			goto rx_error;
172		}
173
174		cisco_data = (struct cisco_packet *)(skb->data + sizeof
175						    (struct hdlc_header));
176
177		switch (ntohl(cisco_data->type)) {
178		case CISCO_ADDR_REQ: /* Stolen from syncppp.c :-) */
179			rcu_read_lock();
180			in_dev = __in_dev_get_rcu(dev);
181			addr = 0;
182			mask = ~cpu_to_be32(0); /* is the mask correct? */
183
184			if (in_dev != NULL) {
185				const struct in_ifaddr *ifa;
186
187				in_dev_for_each_ifa_rcu(ifa, in_dev) {
188					if (strcmp(dev->name,
189						   ifa->ifa_label) == 0) {
190						addr = ifa->ifa_local;
191						mask = ifa->ifa_mask;
192						break;
193					}
194				}
195
196				cisco_keepalive_send(dev, CISCO_ADDR_REPLY,
197						     addr, mask);
198			}
199			rcu_read_unlock();
200			dev_kfree_skb_any(skb);
201			return NET_RX_SUCCESS;
202
203		case CISCO_ADDR_REPLY:
204			netdev_info(dev, "Unexpected Cisco IP address reply\n");
205			goto rx_error;
206
207		case CISCO_KEEPALIVE_REQ:
208			spin_lock(&st->lock);
209			st->rxseq = ntohl(cisco_data->par1);
210			ack = ntohl(cisco_data->par2);
211			if (ack && (ack == st->txseq ||
212				    /* our current REQ may be in transit */
213				    ack == st->txseq - 1)) {
214				st->last_poll = jiffies;
215				if (!st->up) {
216					u32 sec, min, hrs, days;
217
218					sec = ntohl(cisco_data->time) / 1000;
219					min = sec / 60; sec -= min * 60;
220					hrs = min / 60; min -= hrs * 60;
221					days = hrs / 24; hrs -= days * 24;
222					netdev_info(dev, "Link up (peer uptime %ud%uh%um%us)\n",
223						    days, hrs, min, sec);
224					netif_dormant_off(dev);
225					st->up = 1;
226				}
227			}
228			spin_unlock(&st->lock);
229
230			dev_kfree_skb_any(skb);
231			return NET_RX_SUCCESS;
232		} /* switch (keepalive type) */
233	} /* switch (protocol) */
234
235	netdev_info(dev, "Unsupported protocol %x\n", ntohs(data->protocol));
236	dev_kfree_skb_any(skb);
237	return NET_RX_DROP;
238
239rx_error:
240	dev->stats.rx_errors++; /* Mark error */
241	dev_kfree_skb_any(skb);
242	return NET_RX_DROP;
243}
244
245static void cisco_timer(struct timer_list *t)
246{
247	struct cisco_state *st = from_timer(st, t, timer);
248	struct net_device *dev = st->dev;
249
250	spin_lock(&st->lock);
251	if (st->up &&
252	    time_after(jiffies, st->last_poll + st->settings.timeout * HZ)) {
253		st->up = 0;
254		netdev_info(dev, "Link down\n");
255		netif_dormant_on(dev);
256	}
257
258	cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ, htonl(++st->txseq),
259			     htonl(st->rxseq));
260	spin_unlock(&st->lock);
261
262	st->timer.expires = jiffies + st->settings.interval * HZ;
263	add_timer(&st->timer);
264}
265
266static void cisco_start(struct net_device *dev)
267{
268	hdlc_device *hdlc = dev_to_hdlc(dev);
269	struct cisco_state *st = state(hdlc);
270	unsigned long flags;
271
272	spin_lock_irqsave(&st->lock, flags);
273	st->up = st->txseq = st->rxseq = 0;
274	spin_unlock_irqrestore(&st->lock, flags);
275
276	st->dev = dev;
277	timer_setup(&st->timer, cisco_timer, 0);
278	st->timer.expires = jiffies + HZ; /* First poll after 1 s */
279	add_timer(&st->timer);
280}
281
282static void cisco_stop(struct net_device *dev)
283{
284	hdlc_device *hdlc = dev_to_hdlc(dev);
285	struct cisco_state *st = state(hdlc);
286	unsigned long flags;
287
288	del_timer_sync(&st->timer);
289
290	spin_lock_irqsave(&st->lock, flags);
291	netif_dormant_on(dev);
292	st->up = st->txseq = 0;
293	spin_unlock_irqrestore(&st->lock, flags);
294}
295
296static struct hdlc_proto proto = {
297	.start		= cisco_start,
298	.stop		= cisco_stop,
299	.type_trans	= cisco_type_trans,
300	.ioctl		= cisco_ioctl,
301	.netif_rx	= cisco_rx,
302	.module		= THIS_MODULE,
303};
304
305static const struct header_ops cisco_header_ops = {
306	.create = cisco_hard_header,
307};
308
309static int cisco_ioctl(struct net_device *dev, struct if_settings *ifs)
310{
311	cisco_proto __user *cisco_s = ifs->ifs_ifsu.cisco;
312	const size_t size = sizeof(cisco_proto);
313	cisco_proto new_settings;
314	hdlc_device *hdlc = dev_to_hdlc(dev);
315	int result;
316
317	switch (ifs->type) {
318	case IF_GET_PROTO:
319		if (dev_to_hdlc(dev)->proto != &proto)
320			return -EINVAL;
321		ifs->type = IF_PROTO_CISCO;
322		if (ifs->size < size) {
323			ifs->size = size; /* data size wanted */
324			return -ENOBUFS;
325		}
326		if (copy_to_user(cisco_s, &state(hdlc)->settings, size))
327			return -EFAULT;
328		return 0;
329
330	case IF_PROTO_CISCO:
331		if (!capable(CAP_NET_ADMIN))
332			return -EPERM;
333
334		if (dev->flags & IFF_UP)
335			return -EBUSY;
336
337		if (copy_from_user(&new_settings, cisco_s, size))
338			return -EFAULT;
339
340		if (new_settings.interval < 1 ||
341		    new_settings.timeout < 2)
342			return -EINVAL;
343
344		result = hdlc->attach(dev, ENCODING_NRZ,
345				      PARITY_CRC16_PR1_CCITT);
346		if (result)
347			return result;
348
349		result = attach_hdlc_protocol(dev, &proto,
350					      sizeof(struct cisco_state));
351		if (result)
352			return result;
353
354		memcpy(&state(hdlc)->settings, &new_settings, size);
355		spin_lock_init(&state(hdlc)->lock);
356		dev->header_ops = &cisco_header_ops;
357		dev->hard_header_len = sizeof(struct hdlc_header);
358		dev->type = ARPHRD_CISCO;
359		call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
360		netif_dormant_on(dev);
361		return 0;
362	}
363
364	return -EINVAL;
365}
366
367static int __init hdlc_cisco_init(void)
368{
369	register_hdlc_protocol(&proto);
370	return 0;
371}
372
373static void __exit hdlc_cisco_exit(void)
374{
375	unregister_hdlc_protocol(&proto);
376}
377
378module_init(hdlc_cisco_init);
379module_exit(hdlc_cisco_exit);
380
381MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
382MODULE_DESCRIPTION("Cisco HDLC protocol support for generic HDLC");
383MODULE_LICENSE("GPL v2");
v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Generic HDLC support routines for Linux
  4 * Cisco HDLC support
  5 *
  6 * Copyright (C) 2000 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
  7 */
  8
  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	/* Cisco multicast address */
 24#define CISCO_UNICAST		0x0F	/* Cisco unicast address */
 25#define CISCO_KEEPALIVE		0x8035	/* Cisco keepalive protocol */
 26#define CISCO_SYS_INFO		0x2000	/* Cisco interface/system info */
 27#define CISCO_ADDR_REQ		0	/* Cisco address request */
 28#define CISCO_ADDR_REPLY	1	/* Cisco address reply */
 29#define CISCO_KEEPALIVE_REQ	2	/* Cisco keepalive request */
 30
 31struct hdlc_header {
 32	u8 address;
 33	u8 control;
 34	__be16 protocol;
 35} __packed;
 36
 37struct cisco_packet {
 38	__be32 type;		/* code */
 39	__be32 par1;
 40	__be32 par2;
 41	__be16 rel;		/* reliability */
 42	__be32 time;
 43} __packed;
 44#define	CISCO_PACKET_LEN	18
 45#define	CISCO_BIG_PACKET_LEN	20
 46
 47struct cisco_state {
 48	cisco_proto settings;
 49
 50	struct timer_list timer;
 51	struct net_device *dev;
 52	spinlock_t lock;
 53	unsigned long last_poll;
 54	int up;
 55	u32 txseq; /* TX sequence number, 0 = none */
 56	u32 rxseq; /* RX sequence number */
 57};
 58
 59static int cisco_ioctl(struct net_device *dev, struct if_settings *ifs);
 60
 61static inline struct cisco_state *state(hdlc_device *hdlc)
 62{
 63	return (struct cisco_state *)hdlc->state;
 64}
 65
 66static int cisco_hard_header(struct sk_buff *skb, struct net_device *dev,
 67			     u16 type, const void *daddr, const void *saddr,
 68			     unsigned int len)
 69{
 70	struct hdlc_header *data;
 71#ifdef DEBUG_HARD_HEADER
 72	netdev_dbg(dev, "%s called\n", __func__);
 73#endif
 74
 75	skb_push(skb, sizeof(struct hdlc_header));
 76	data = (struct hdlc_header *)skb->data;
 77	if (type == CISCO_KEEPALIVE)
 78		data->address = CISCO_MULTICAST;
 79	else
 80		data->address = CISCO_UNICAST;
 81	data->control = 0;
 82	data->protocol = htons(type);
 83
 84	return sizeof(struct hdlc_header);
 85}
 86
 87static void cisco_keepalive_send(struct net_device *dev, u32 type,
 88				 __be32 par1, __be32 par2)
 89{
 90	struct sk_buff *skb;
 91	struct cisco_packet *data;
 92
 93	skb = dev_alloc_skb(sizeof(struct hdlc_header) +
 94			    sizeof(struct cisco_packet));
 95	if (!skb)
 96		return;
 97
 98	skb_reserve(skb, 4);
 99	cisco_hard_header(skb, dev, CISCO_KEEPALIVE, NULL, NULL, 0);
100	data = (struct cisco_packet *)(skb->data + 4);
101
102	data->type = htonl(type);
103	data->par1 = par1;
104	data->par2 = par2;
105	data->rel = cpu_to_be16(0xFFFF);
106	/* we will need do_div here if 1000 % HZ != 0 */
107	data->time = htonl((jiffies - INITIAL_JIFFIES) * (1000 / HZ));
108
109	skb_put(skb, sizeof(struct cisco_packet));
110	skb->priority = TC_PRIO_CONTROL;
111	skb->dev = dev;
112	skb->protocol = htons(ETH_P_HDLC);
113	skb_reset_network_header(skb);
114
115	dev_queue_xmit(skb);
116}
117
118static __be16 cisco_type_trans(struct sk_buff *skb, struct net_device *dev)
119{
120	struct hdlc_header *data = (struct hdlc_header *)skb->data;
121
122	if (skb->len < sizeof(struct hdlc_header))
123		return cpu_to_be16(ETH_P_HDLC);
124
125	if (data->address != CISCO_MULTICAST &&
126	    data->address != CISCO_UNICAST)
127		return cpu_to_be16(ETH_P_HDLC);
128
129	switch (data->protocol) {
130	case cpu_to_be16(ETH_P_IP):
131	case cpu_to_be16(ETH_P_IPX):
132	case cpu_to_be16(ETH_P_IPV6):
133		skb_pull(skb, sizeof(struct hdlc_header));
134		return data->protocol;
135	default:
136		return cpu_to_be16(ETH_P_HDLC);
137	}
138}
139
140static int cisco_rx(struct sk_buff *skb)
141{
142	struct net_device *dev = skb->dev;
143	hdlc_device *hdlc = dev_to_hdlc(dev);
144	struct cisco_state *st = state(hdlc);
145	struct hdlc_header *data = (struct hdlc_header *)skb->data;
146	struct cisco_packet *cisco_data;
147	struct in_device *in_dev;
148	__be32 addr, mask;
149	u32 ack;
150
151	if (skb->len < sizeof(struct hdlc_header))
152		goto rx_error;
153
154	if (data->address != CISCO_MULTICAST &&
155	    data->address != CISCO_UNICAST)
156		goto rx_error;
157
158	switch (ntohs(data->protocol)) {
159	case CISCO_SYS_INFO:
160		/* Packet is not needed, drop it. */
161		dev_kfree_skb_any(skb);
162		return NET_RX_SUCCESS;
163
164	case CISCO_KEEPALIVE:
165		if ((skb->len != sizeof(struct hdlc_header) +
166		     CISCO_PACKET_LEN) &&
167		    (skb->len != sizeof(struct hdlc_header) +
168		     CISCO_BIG_PACKET_LEN)) {
169			netdev_info(dev, "Invalid length of Cisco control packet (%d bytes)\n",
170				    skb->len);
171			goto rx_error;
172		}
173
174		cisco_data = (struct cisco_packet *)(skb->data + sizeof
175						    (struct hdlc_header));
176
177		switch (ntohl(cisco_data->type)) {
178		case CISCO_ADDR_REQ: /* Stolen from syncppp.c :-) */
179			rcu_read_lock();
180			in_dev = __in_dev_get_rcu(dev);
181			addr = 0;
182			mask = ~cpu_to_be32(0); /* is the mask correct? */
183
184			if (in_dev != NULL) {
185				const struct in_ifaddr *ifa;
186
187				in_dev_for_each_ifa_rcu(ifa, in_dev) {
188					if (strcmp(dev->name,
189						   ifa->ifa_label) == 0) {
190						addr = ifa->ifa_local;
191						mask = ifa->ifa_mask;
192						break;
193					}
194				}
195
196				cisco_keepalive_send(dev, CISCO_ADDR_REPLY,
197						     addr, mask);
198			}
199			rcu_read_unlock();
200			dev_kfree_skb_any(skb);
201			return NET_RX_SUCCESS;
202
203		case CISCO_ADDR_REPLY:
204			netdev_info(dev, "Unexpected Cisco IP address reply\n");
205			goto rx_error;
206
207		case CISCO_KEEPALIVE_REQ:
208			spin_lock(&st->lock);
209			st->rxseq = ntohl(cisco_data->par1);
210			ack = ntohl(cisco_data->par2);
211			if (ack && (ack == st->txseq ||
212				    /* our current REQ may be in transit */
213				    ack == st->txseq - 1)) {
214				st->last_poll = jiffies;
215				if (!st->up) {
216					u32 sec, min, hrs, days;
217
218					sec = ntohl(cisco_data->time) / 1000;
219					min = sec / 60; sec -= min * 60;
220					hrs = min / 60; min -= hrs * 60;
221					days = hrs / 24; hrs -= days * 24;
222					netdev_info(dev, "Link up (peer uptime %ud%uh%um%us)\n",
223						    days, hrs, min, sec);
224					netif_dormant_off(dev);
225					st->up = 1;
226				}
227			}
228			spin_unlock(&st->lock);
229
230			dev_kfree_skb_any(skb);
231			return NET_RX_SUCCESS;
232		} /* switch (keepalive type) */
233	} /* switch (protocol) */
234
235	netdev_info(dev, "Unsupported protocol %x\n", ntohs(data->protocol));
236	dev_kfree_skb_any(skb);
237	return NET_RX_DROP;
238
239rx_error:
240	dev->stats.rx_errors++; /* Mark error */
241	dev_kfree_skb_any(skb);
242	return NET_RX_DROP;
243}
244
245static void cisco_timer(struct timer_list *t)
246{
247	struct cisco_state *st = from_timer(st, t, timer);
248	struct net_device *dev = st->dev;
249
250	spin_lock(&st->lock);
251	if (st->up &&
252	    time_after(jiffies, st->last_poll + st->settings.timeout * HZ)) {
253		st->up = 0;
254		netdev_info(dev, "Link down\n");
255		netif_dormant_on(dev);
256	}
257
258	cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ, htonl(++st->txseq),
259			     htonl(st->rxseq));
260	spin_unlock(&st->lock);
261
262	st->timer.expires = jiffies + st->settings.interval * HZ;
263	add_timer(&st->timer);
264}
265
266static void cisco_start(struct net_device *dev)
267{
268	hdlc_device *hdlc = dev_to_hdlc(dev);
269	struct cisco_state *st = state(hdlc);
270	unsigned long flags;
271
272	spin_lock_irqsave(&st->lock, flags);
273	st->up = st->txseq = st->rxseq = 0;
274	spin_unlock_irqrestore(&st->lock, flags);
275
276	st->dev = dev;
277	timer_setup(&st->timer, cisco_timer, 0);
278	st->timer.expires = jiffies + HZ; /* First poll after 1 s */
279	add_timer(&st->timer);
280}
281
282static void cisco_stop(struct net_device *dev)
283{
284	hdlc_device *hdlc = dev_to_hdlc(dev);
285	struct cisco_state *st = state(hdlc);
286	unsigned long flags;
287
288	del_timer_sync(&st->timer);
289
290	spin_lock_irqsave(&st->lock, flags);
291	netif_dormant_on(dev);
292	st->up = st->txseq = 0;
293	spin_unlock_irqrestore(&st->lock, flags);
294}
295
296static struct hdlc_proto proto = {
297	.start		= cisco_start,
298	.stop		= cisco_stop,
299	.type_trans	= cisco_type_trans,
300	.ioctl		= cisco_ioctl,
301	.netif_rx	= cisco_rx,
302	.module		= THIS_MODULE,
303};
304
305static const struct header_ops cisco_header_ops = {
306	.create = cisco_hard_header,
307};
308
309static int cisco_ioctl(struct net_device *dev, struct if_settings *ifs)
310{
311	cisco_proto __user *cisco_s = ifs->ifs_ifsu.cisco;
312	const size_t size = sizeof(cisco_proto);
313	cisco_proto new_settings;
314	hdlc_device *hdlc = dev_to_hdlc(dev);
315	int result;
316
317	switch (ifs->type) {
318	case IF_GET_PROTO:
319		if (dev_to_hdlc(dev)->proto != &proto)
320			return -EINVAL;
321		ifs->type = IF_PROTO_CISCO;
322		if (ifs->size < size) {
323			ifs->size = size; /* data size wanted */
324			return -ENOBUFS;
325		}
326		if (copy_to_user(cisco_s, &state(hdlc)->settings, size))
327			return -EFAULT;
328		return 0;
329
330	case IF_PROTO_CISCO:
331		if (!capable(CAP_NET_ADMIN))
332			return -EPERM;
333
334		if (dev->flags & IFF_UP)
335			return -EBUSY;
336
337		if (copy_from_user(&new_settings, cisco_s, size))
338			return -EFAULT;
339
340		if (new_settings.interval < 1 ||
341		    new_settings.timeout < 2)
342			return -EINVAL;
343
344		result = hdlc->attach(dev, ENCODING_NRZ,
345				      PARITY_CRC16_PR1_CCITT);
346		if (result)
347			return result;
348
349		result = attach_hdlc_protocol(dev, &proto,
350					      sizeof(struct cisco_state));
351		if (result)
352			return result;
353
354		memcpy(&state(hdlc)->settings, &new_settings, size);
355		spin_lock_init(&state(hdlc)->lock);
356		dev->header_ops = &cisco_header_ops;
357		dev->hard_header_len = sizeof(struct hdlc_header);
358		dev->type = ARPHRD_CISCO;
359		call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
360		netif_dormant_on(dev);
361		return 0;
362	}
363
364	return -EINVAL;
365}
366
367static int __init hdlc_cisco_init(void)
368{
369	register_hdlc_protocol(&proto);
370	return 0;
371}
372
373static void __exit hdlc_cisco_exit(void)
374{
375	unregister_hdlc_protocol(&proto);
376}
377
378module_init(hdlc_cisco_init);
379module_exit(hdlc_cisco_exit);
380
381MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
382MODULE_DESCRIPTION("Cisco HDLC protocol support for generic HDLC");
383MODULE_LICENSE("GPL v2");