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
));
48 u16 rel
; /* reliability */
50 }__attribute__ ((packed
));
51 #define CISCO_PACKET_LEN 18
52 #define CISCO_BIG_PACKET_LEN 20
58 struct timer_list timer
;
59 unsigned long last_poll
;
62 u32 txseq
; /* TX sequence number */
63 u32 rxseq
; /* RX sequence number */
67 static int cisco_ioctl(struct net_device
*dev
, struct ifreq
*ifr
);
70 static inline struct cisco_state
* state(hdlc_device
*hdlc
)
72 return(struct cisco_state
*)(hdlc
->state
);
76 static int cisco_hard_header(struct sk_buff
*skb
, struct net_device
*dev
,
77 u16 type
, void *daddr
, void *saddr
,
80 struct hdlc_header
*data
;
81 #ifdef DEBUG_HARD_HEADER
82 printk(KERN_DEBUG
"%s: cisco_hard_header called\n", dev
->name
);
85 skb_push(skb
, sizeof(struct hdlc_header
));
86 data
= (struct hdlc_header
*)skb
->data
;
87 if (type
== CISCO_KEEPALIVE
)
88 data
->address
= CISCO_MULTICAST
;
90 data
->address
= CISCO_UNICAST
;
92 data
->protocol
= htons(type
);
94 return sizeof(struct hdlc_header
);
99 static void cisco_keepalive_send(struct net_device
*dev
, u32 type
,
103 struct cisco_packet
*data
;
105 skb
= dev_alloc_skb(sizeof(struct hdlc_header
) +
106 sizeof(struct cisco_packet
));
109 "%s: Memory squeeze on cisco_keepalive_send()\n",
114 cisco_hard_header(skb
, dev
, CISCO_KEEPALIVE
, NULL
, NULL
, 0);
115 data
= (struct cisco_packet
*)(skb
->data
+ 4);
117 data
->type
= htonl(type
);
118 data
->par1
= htonl(par1
);
119 data
->par2
= htonl(par2
);
121 /* we will need do_div here if 1000 % HZ != 0 */
122 data
->time
= htonl((jiffies
- INITIAL_JIFFIES
) * (1000 / HZ
));
124 skb_put(skb
, sizeof(struct cisco_packet
));
125 skb
->priority
= TC_PRIO_CONTROL
;
127 skb
->nh
.raw
= skb
->data
;
134 static __be16
cisco_type_trans(struct sk_buff
*skb
, struct net_device
*dev
)
136 struct hdlc_header
*data
= (struct hdlc_header
*)skb
->data
;
138 if (skb
->len
< sizeof(struct hdlc_header
))
139 return __constant_htons(ETH_P_HDLC
);
141 if (data
->address
!= CISCO_MULTICAST
&&
142 data
->address
!= CISCO_UNICAST
)
143 return __constant_htons(ETH_P_HDLC
);
145 switch(data
->protocol
) {
146 case __constant_htons(ETH_P_IP
):
147 case __constant_htons(ETH_P_IPX
):
148 case __constant_htons(ETH_P_IPV6
):
149 skb_pull(skb
, sizeof(struct hdlc_header
));
150 return data
->protocol
;
152 return __constant_htons(ETH_P_HDLC
);
157 static int cisco_rx(struct sk_buff
*skb
)
159 struct net_device
*dev
= skb
->dev
;
160 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
161 struct hdlc_header
*data
= (struct hdlc_header
*)skb
->data
;
162 struct cisco_packet
*cisco_data
;
163 struct in_device
*in_dev
;
166 if (skb
->len
< sizeof(struct hdlc_header
))
169 if (data
->address
!= CISCO_MULTICAST
&&
170 data
->address
!= CISCO_UNICAST
)
173 switch(ntohs(data
->protocol
)) {
175 /* Packet is not needed, drop it. */
176 dev_kfree_skb_any(skb
);
177 return NET_RX_SUCCESS
;
179 case CISCO_KEEPALIVE
:
180 if ((skb
->len
!= sizeof(struct hdlc_header
) +
182 (skb
->len
!= sizeof(struct hdlc_header
) +
183 CISCO_BIG_PACKET_LEN
)) {
184 printk(KERN_INFO
"%s: Invalid length of Cisco control"
185 " packet (%d bytes)\n", dev
->name
, skb
->len
);
189 cisco_data
= (struct cisco_packet
*)(skb
->data
+ sizeof
190 (struct hdlc_header
));
192 switch(ntohl (cisco_data
->type
)) {
193 case CISCO_ADDR_REQ
: /* Stolen from syncppp.c :-) */
194 in_dev
= dev
->ip_ptr
;
196 mask
= ~0; /* is the mask correct? */
198 if (in_dev
!= NULL
) {
199 struct in_ifaddr
**ifap
= &in_dev
->ifa_list
;
201 while (*ifap
!= NULL
) {
202 if (strcmp(dev
->name
,
203 (*ifap
)->ifa_label
) == 0) {
204 addr
= (*ifap
)->ifa_local
;
205 mask
= (*ifap
)->ifa_mask
;
208 ifap
= &(*ifap
)->ifa_next
;
211 cisco_keepalive_send(dev
, CISCO_ADDR_REPLY
,
214 dev_kfree_skb_any(skb
);
215 return NET_RX_SUCCESS
;
217 case CISCO_ADDR_REPLY
:
218 printk(KERN_INFO
"%s: Unexpected Cisco IP address "
219 "reply\n", dev
->name
);
222 case CISCO_KEEPALIVE_REQ
:
223 state(hdlc
)->rxseq
= ntohl(cisco_data
->par1
);
224 if (state(hdlc
)->request_sent
&&
225 ntohl(cisco_data
->par2
) == state(hdlc
)->txseq
) {
226 state(hdlc
)->last_poll
= jiffies
;
227 if (!state(hdlc
)->up
) {
228 u32 sec
, min
, hrs
, days
;
229 sec
= ntohl(cisco_data
->time
) / 1000;
230 min
= sec
/ 60; sec
-= min
* 60;
231 hrs
= min
/ 60; min
-= hrs
* 60;
232 days
= hrs
/ 24; hrs
-= days
* 24;
233 printk(KERN_INFO
"%s: Link up (peer "
234 "uptime %ud%uh%um%us)\n",
235 dev
->name
, days
, hrs
,
237 netif_dormant_off(dev
);
242 dev_kfree_skb_any(skb
);
243 return NET_RX_SUCCESS
;
244 } /* switch(keepalive type) */
245 } /* switch(protocol) */
247 printk(KERN_INFO
"%s: Unsupported protocol %x\n", dev
->name
,
249 dev_kfree_skb_any(skb
);
253 dev_to_desc(dev
)->stats
.rx_errors
++; /* Mark error */
254 dev_kfree_skb_any(skb
);
260 static void cisco_timer(unsigned long arg
)
262 struct net_device
*dev
= (struct net_device
*)arg
;
263 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
265 if (state(hdlc
)->up
&&
266 time_after(jiffies
, state(hdlc
)->last_poll
+
267 state(hdlc
)->settings
.timeout
* HZ
)) {
269 printk(KERN_INFO
"%s: Link down\n", dev
->name
);
270 netif_dormant_on(dev
);
273 cisco_keepalive_send(dev
, CISCO_KEEPALIVE_REQ
, ++state(hdlc
)->txseq
,
275 state(hdlc
)->request_sent
= 1;
276 state(hdlc
)->timer
.expires
= jiffies
+
277 state(hdlc
)->settings
.interval
* HZ
;
278 state(hdlc
)->timer
.function
= cisco_timer
;
279 state(hdlc
)->timer
.data
= arg
;
280 add_timer(&state(hdlc
)->timer
);
285 static void cisco_start(struct net_device
*dev
)
287 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
289 state(hdlc
)->request_sent
= 0;
290 state(hdlc
)->txseq
= state(hdlc
)->rxseq
= 0;
292 init_timer(&state(hdlc
)->timer
);
293 state(hdlc
)->timer
.expires
= jiffies
+ HZ
; /*First poll after 1s*/
294 state(hdlc
)->timer
.function
= cisco_timer
;
295 state(hdlc
)->timer
.data
= (unsigned long)dev
;
296 add_timer(&state(hdlc
)->timer
);
301 static void cisco_stop(struct net_device
*dev
)
303 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
304 del_timer_sync(&state(hdlc
)->timer
);
305 netif_dormant_on(dev
);
307 state(hdlc
)->request_sent
= 0;
312 static struct hdlc_proto proto
= {
313 .start
= cisco_start
,
315 .type_trans
= cisco_type_trans
,
316 .ioctl
= cisco_ioctl
,
317 .module
= THIS_MODULE
,
321 static int cisco_ioctl(struct net_device
*dev
, struct ifreq
*ifr
)
323 cisco_proto __user
*cisco_s
= ifr
->ifr_settings
.ifs_ifsu
.cisco
;
324 const size_t size
= sizeof(cisco_proto
);
325 cisco_proto new_settings
;
326 hdlc_device
*hdlc
= dev_to_hdlc(dev
);
329 switch (ifr
->ifr_settings
.type
) {
331 if (dev_to_hdlc(dev
)->proto
!= &proto
)
333 ifr
->ifr_settings
.type
= IF_PROTO_CISCO
;
334 if (ifr
->ifr_settings
.size
< size
) {
335 ifr
->ifr_settings
.size
= size
; /* data size wanted */
338 if (copy_to_user(cisco_s
, &state(hdlc
)->settings
, size
))
343 if(!capable(CAP_NET_ADMIN
))
346 if(dev
->flags
& IFF_UP
)
349 if (copy_from_user(&new_settings
, cisco_s
, size
))
352 if (new_settings
.interval
< 1 ||
353 new_settings
.timeout
< 2)
356 result
=hdlc
->attach(dev
, ENCODING_NRZ
,PARITY_CRC16_PR1_CCITT
);
360 result
= attach_hdlc_protocol(dev
, &proto
, cisco_rx
,
361 sizeof(struct cisco_state
));
365 memcpy(&state(hdlc
)->settings
, &new_settings
, size
);
366 dev
->hard_start_xmit
= hdlc
->xmit
;
367 dev
->hard_header
= cisco_hard_header
;
368 dev
->hard_header_cache
= NULL
;
369 dev
->type
= ARPHRD_CISCO
;
370 dev
->flags
= IFF_POINTOPOINT
| IFF_NOARP
;
372 netif_dormant_on(dev
);
380 static int __init
mod_init(void)
382 register_hdlc_protocol(&proto
);
388 static void __exit
mod_exit(void)
390 unregister_hdlc_protocol(&proto
);
394 module_init(mod_init
);
395 module_exit(mod_exit
);
397 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
398 MODULE_DESCRIPTION("Cisco HDLC protocol support for generic HDLC");
399 MODULE_LICENSE("GPL v2");