2 * Generic HDLC support routines for Linux
5 * Copyright (C) 2000 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
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.
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/poll.h>
16 #include <linux/errno.h>
17 #include <linux/if_arp.h>
18 #include <linux/init.h>
19 #include <linux/skbuff.h>
20 #include <linux/pkt_sched.h>
21 #include <linux/inetdevice.h>
22 #include <linux/lapb.h>
23 #include <linux/rtnetlink.h>
24 #include <linux/hdlc.h>
26 #undef DEBUG_HARD_HEADER
28 #define CISCO_MULTICAST 0x8F /* Cisco multicast address */
29 #define CISCO_UNICAST 0x0F /* Cisco unicast address */
30 #define CISCO_KEEPALIVE 0x8035 /* Cisco keepalive protocol */
31 #define CISCO_SYS_INFO 0x2000 /* Cisco interface/system info */
32 #define CISCO_ADDR_REQ 0 /* Cisco address request */
33 #define CISCO_ADDR_REPLY 1 /* Cisco address reply */
34 #define CISCO_KEEPALIVE_REQ 2 /* Cisco keepalive request */
41 }__attribute__ ((packed
));
45 __be32 type
; /* code */
48 __be16 rel
; /* reliability */
50 }__attribute__ ((packed
));
51 #define CISCO_PACKET_LEN 18
52 #define CISCO_BIG_PACKET_LEN 20
58 struct timer_list timer
;
60 unsigned long last_poll
;
63 u32 txseq
; /* TX sequence number */
64 u32 rxseq
; /* RX sequence number */
68 static int cisco_ioctl(struct net_device
*dev
, struct ifreq
*ifr
);
71 static inline struct cisco_state
* state(hdlc_device
*hdlc
)
73 return(struct cisco_state
*)(hdlc
->state
);
77 static int cisco_hard_header(struct sk_buff
*skb
, struct net_device
*dev
,
78 u16 type
, const void *daddr
, const void *saddr
,
81 struct hdlc_header
*data
;
82 #ifdef DEBUG_HARD_HEADER
83 printk(KERN_DEBUG
"%s: cisco_hard_header called\n", dev
->name
);
86 skb_push(skb
, sizeof(struct hdlc_header
));
87 data
= (struct hdlc_header
*)skb
->data
;
88 if (type
== CISCO_KEEPALIVE
)
89 data
->address
= CISCO_MULTICAST
;
91 data
->address
= CISCO_UNICAST
;
93 data
->protocol
= htons(type
);
95 return sizeof(struct hdlc_header
);
100 static void cisco_keepalive_send(struct net_device
*dev
, u32 type
,
101 __be32 par1
, __be32 par2
)
104 struct cisco_packet
*data
;
106 skb
= dev_alloc_skb(sizeof(struct hdlc_header
) +
107 sizeof(struct cisco_packet
));
110 "%s: Memory squeeze on cisco_keepalive_send()\n",
115 cisco_hard_header(skb
, dev
, CISCO_KEEPALIVE
, NULL
, NULL
, 0);
116 data
= (struct cisco_packet
*)(skb
->data
+ 4);
118 data
->type
= htonl(type
);
121 data
->rel
= __constant_htons(0xFFFF);
122 /* we will need do_div here if 1000 % HZ != 0 */
123 data
->time
= htonl((jiffies
- INITIAL_JIFFIES
) * (1000 / HZ
));
125 skb_put(skb
, sizeof(struct cisco_packet
));
126 skb
->priority
= TC_PRIO_CONTROL
;
128 skb_reset_network_header(skb
);
135 static __be16
cisco_type_trans(struct sk_buff
*skb
, struct net_device
*dev
)
137 struct hdlc_header
*data
= (struct hdlc_header
*)skb
->data
;
139 if (skb
->len
< sizeof(struct hdlc_header
))
140 return __constant_htons(ETH_P_HDLC
);
142 if (data
->address
!= CISCO_MULTICAST
&&
143 data
->address
!= CISCO_UNICAST
)
144 return __constant_htons(ETH_P_HDLC
);
146 switch(data
->protocol
) {
147 case __constant_htons(ETH_P_IP
):
148 case __constant_htons(ETH_P_IPX
):
149 case __constant_htons(ETH_P_IPV6
):
150 skb_pull(skb
, sizeof(struct hdlc_header
));
151 return data
->protocol
;
153 return __constant_htons(ETH_P_HDLC
);
158 static int cisco_rx(struct sk_buff
*skb
)
160 struct net_device
*dev
= skb
->dev
;
161 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
162 struct cisco_state
*st
= state(hdlc
);
163 struct hdlc_header
*data
= (struct hdlc_header
*)skb
->data
;
164 struct cisco_packet
*cisco_data
;
165 struct in_device
*in_dev
;
168 if (skb
->len
< sizeof(struct hdlc_header
))
171 if (data
->address
!= CISCO_MULTICAST
&&
172 data
->address
!= CISCO_UNICAST
)
175 switch(ntohs(data
->protocol
)) {
177 /* Packet is not needed, drop it. */
178 dev_kfree_skb_any(skb
);
179 return NET_RX_SUCCESS
;
181 case CISCO_KEEPALIVE
:
182 if ((skb
->len
!= sizeof(struct hdlc_header
) +
184 (skb
->len
!= sizeof(struct hdlc_header
) +
185 CISCO_BIG_PACKET_LEN
)) {
186 printk(KERN_INFO
"%s: Invalid length of Cisco control"
187 " packet (%d bytes)\n", dev
->name
, skb
->len
);
191 cisco_data
= (struct cisco_packet
*)(skb
->data
+ sizeof
192 (struct hdlc_header
));
194 switch(ntohl (cisco_data
->type
)) {
195 case CISCO_ADDR_REQ
: /* Stolen from syncppp.c :-) */
196 in_dev
= dev
->ip_ptr
;
198 mask
= __constant_htonl(~0); /* is the mask correct? */
200 if (in_dev
!= NULL
) {
201 struct in_ifaddr
**ifap
= &in_dev
->ifa_list
;
203 while (*ifap
!= NULL
) {
204 if (strcmp(dev
->name
,
205 (*ifap
)->ifa_label
) == 0) {
206 addr
= (*ifap
)->ifa_local
;
207 mask
= (*ifap
)->ifa_mask
;
210 ifap
= &(*ifap
)->ifa_next
;
213 cisco_keepalive_send(dev
, CISCO_ADDR_REPLY
,
216 dev_kfree_skb_any(skb
);
217 return NET_RX_SUCCESS
;
219 case CISCO_ADDR_REPLY
:
220 printk(KERN_INFO
"%s: Unexpected Cisco IP address "
221 "reply\n", dev
->name
);
224 case CISCO_KEEPALIVE_REQ
:
225 spin_lock(&st
->lock
);
226 st
->rxseq
= ntohl(cisco_data
->par1
);
227 if (st
->request_sent
&&
228 ntohl(cisco_data
->par2
) == st
->txseq
) {
229 st
->last_poll
= jiffies
;
231 u32 sec
, min
, hrs
, days
;
232 sec
= ntohl(cisco_data
->time
) / 1000;
233 min
= sec
/ 60; sec
-= min
* 60;
234 hrs
= min
/ 60; min
-= hrs
* 60;
235 days
= hrs
/ 24; hrs
-= days
* 24;
236 printk(KERN_INFO
"%s: Link up (peer "
237 "uptime %ud%uh%um%us)\n",
238 dev
->name
, days
, hrs
, min
, sec
);
239 netif_dormant_off(dev
);
243 spin_unlock(&st
->lock
);
245 dev_kfree_skb_any(skb
);
246 return NET_RX_SUCCESS
;
247 } /* switch(keepalive type) */
248 } /* switch(protocol) */
250 printk(KERN_INFO
"%s: Unsupported protocol %x\n", dev
->name
,
251 ntohs(data
->protocol
));
252 dev_kfree_skb_any(skb
);
256 dev_to_hdlc(dev
)->stats
.rx_errors
++; /* Mark error */
257 dev_kfree_skb_any(skb
);
263 static void cisco_timer(unsigned long arg
)
265 struct net_device
*dev
= (struct net_device
*)arg
;
266 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
267 struct cisco_state
*st
= state(hdlc
);
269 spin_lock(&st
->lock
);
271 time_after(jiffies
, st
->last_poll
+ st
->settings
.timeout
* HZ
)) {
273 printk(KERN_INFO
"%s: Link down\n", dev
->name
);
274 netif_dormant_on(dev
);
277 cisco_keepalive_send(dev
, CISCO_KEEPALIVE_REQ
, htonl(++st
->txseq
),
279 st
->request_sent
= 1;
280 spin_unlock(&st
->lock
);
282 st
->timer
.expires
= jiffies
+ st
->settings
.interval
* HZ
;
283 st
->timer
.function
= cisco_timer
;
284 st
->timer
.data
= arg
;
285 add_timer(&st
->timer
);
290 static void cisco_start(struct net_device
*dev
)
292 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
293 struct cisco_state
*st
= state(hdlc
);
296 spin_lock_irqsave(&st
->lock
, flags
);
298 st
->request_sent
= 0;
299 st
->txseq
= st
->rxseq
= 0;
300 spin_unlock_irqrestore(&st
->lock
, flags
);
302 init_timer(&st
->timer
);
303 st
->timer
.expires
= jiffies
+ HZ
; /* First poll after 1 s */
304 st
->timer
.function
= cisco_timer
;
305 st
->timer
.data
= (unsigned long)dev
;
306 add_timer(&st
->timer
);
311 static void cisco_stop(struct net_device
*dev
)
313 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
314 struct cisco_state
*st
= state(hdlc
);
317 del_timer_sync(&st
->timer
);
319 spin_lock_irqsave(&st
->lock
, flags
);
320 netif_dormant_on(dev
);
322 st
->request_sent
= 0;
323 spin_unlock_irqrestore(&st
->lock
, flags
);
327 static struct hdlc_proto proto
= {
328 .start
= cisco_start
,
330 .type_trans
= cisco_type_trans
,
331 .ioctl
= cisco_ioctl
,
332 .netif_rx
= cisco_rx
,
333 .module
= THIS_MODULE
,
336 static const struct header_ops cisco_header_ops
= {
337 .create
= cisco_hard_header
,
340 static int cisco_ioctl(struct net_device
*dev
, struct ifreq
*ifr
)
342 cisco_proto __user
*cisco_s
= ifr
->ifr_settings
.ifs_ifsu
.cisco
;
343 const size_t size
= sizeof(cisco_proto
);
344 cisco_proto new_settings
;
345 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
348 switch (ifr
->ifr_settings
.type
) {
350 if (dev_to_hdlc(dev
)->proto
!= &proto
)
352 ifr
->ifr_settings
.type
= IF_PROTO_CISCO
;
353 if (ifr
->ifr_settings
.size
< size
) {
354 ifr
->ifr_settings
.size
= size
; /* data size wanted */
357 if (copy_to_user(cisco_s
, &state(hdlc
)->settings
, size
))
362 if(!capable(CAP_NET_ADMIN
))
365 if(dev
->flags
& IFF_UP
)
368 if (copy_from_user(&new_settings
, cisco_s
, size
))
371 if (new_settings
.interval
< 1 ||
372 new_settings
.timeout
< 2)
375 result
=hdlc
->attach(dev
, ENCODING_NRZ
,PARITY_CRC16_PR1_CCITT
);
379 result
= attach_hdlc_protocol(dev
, &proto
,
380 sizeof(struct cisco_state
));
384 memcpy(&state(hdlc
)->settings
, &new_settings
, size
);
385 spin_lock_init(&state(hdlc
)->lock
);
386 dev
->hard_start_xmit
= hdlc
->xmit
;
387 dev
->header_ops
= &cisco_header_ops
;
388 dev
->type
= ARPHRD_CISCO
;
389 netif_dormant_on(dev
);
397 static int __init
mod_init(void)
399 register_hdlc_protocol(&proto
);
405 static void __exit
mod_exit(void)
407 unregister_hdlc_protocol(&proto
);
411 module_init(mod_init
);
412 module_exit(mod_exit
);
414 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
415 MODULE_DESCRIPTION("Cisco HDLC protocol support for generic HDLC");
416 MODULE_LICENSE("GPL v2");