]>
Commit | Line | Data |
---|---|---|
25763b3c | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * Generic HDLC support routines for Linux | |
4 | * Cisco HDLC support | |
5 | * | |
eb2a2fd9 | 6 | * Copyright (C) 2000 - 2006 Krzysztof Halasa <khc@pm.waw.pl> |
1da177e4 LT |
7 | */ |
8 | ||
1da177e4 | 9 | #include <linux/errno.h> |
4dfce407 | 10 | #include <linux/hdlc.h> |
1da177e4 | 11 | #include <linux/if_arp.h> |
4dfce407 | 12 | #include <linux/inetdevice.h> |
1da177e4 | 13 | #include <linux/init.h> |
4dfce407 KH |
14 | #include <linux/kernel.h> |
15 | #include <linux/module.h> | |
1da177e4 | 16 | #include <linux/pkt_sched.h> |
4dfce407 | 17 | #include <linux/poll.h> |
1da177e4 | 18 | #include <linux/rtnetlink.h> |
4dfce407 | 19 | #include <linux/skbuff.h> |
1da177e4 LT |
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 | ||
eb2a2fd9 KH |
31 | struct hdlc_header { |
32 | u8 address; | |
33 | u8 control; | |
abf17ffd | 34 | __be16 protocol; |
c1300f37 | 35 | } __packed; |
eb2a2fd9 | 36 | |
eb2a2fd9 | 37 | struct cisco_packet { |
abf17ffd KH |
38 | __be32 type; /* code */ |
39 | __be32 par1; | |
40 | __be32 par2; | |
41 | __be16 rel; /* reliability */ | |
42 | __be32 time; | |
c1300f37 | 43 | } __packed; |
eb2a2fd9 KH |
44 | #define CISCO_PACKET_LEN 18 |
45 | #define CISCO_BIG_PACKET_LEN 20 | |
46 | ||
eb2a2fd9 KH |
47 | struct cisco_state { |
48 | cisco_proto settings; | |
49 | ||
50 | struct timer_list timer; | |
d26c089e | 51 | struct net_device *dev; |
aff26e2f | 52 | spinlock_t lock; |
eb2a2fd9 KH |
53 | unsigned long last_poll; |
54 | int up; | |
9652041d | 55 | u32 txseq; /* TX sequence number, 0 = none */ |
eb2a2fd9 KH |
56 | u32 rxseq; /* RX sequence number */ |
57 | }; | |
58 | ||
ad7eab2a | 59 | static int cisco_ioctl(struct net_device *dev, struct if_settings *ifs); |
eb2a2fd9 | 60 | |
001aa274 | 61 | static inline struct cisco_state *state(hdlc_device *hdlc) |
eb2a2fd9 | 62 | { |
4dfce407 | 63 | return (struct cisco_state *)hdlc->state; |
eb2a2fd9 KH |
64 | } |
65 | ||
1da177e4 | 66 | static int cisco_hard_header(struct sk_buff *skb, struct net_device *dev, |
3b04ddde | 67 | u16 type, const void *daddr, const void *saddr, |
1da177e4 LT |
68 | unsigned int len) |
69 | { | |
eb2a2fd9 | 70 | struct hdlc_header *data; |
1da177e4 | 71 | #ifdef DEBUG_HARD_HEADER |
c68d7248 | 72 | netdev_dbg(dev, "%s called\n", __func__); |
1da177e4 LT |
73 | #endif |
74 | ||
eb2a2fd9 | 75 | skb_push(skb, sizeof(struct hdlc_header)); |
001aa274 | 76 | data = (struct hdlc_header *)skb->data; |
1da177e4 LT |
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 | ||
eb2a2fd9 | 84 | return sizeof(struct hdlc_header); |
1da177e4 LT |
85 | } |
86 | ||
1da177e4 | 87 | static void cisco_keepalive_send(struct net_device *dev, u32 type, |
abf17ffd | 88 | __be32 par1, __be32 par2) |
1da177e4 LT |
89 | { |
90 | struct sk_buff *skb; | |
eb2a2fd9 | 91 | struct cisco_packet *data; |
1da177e4 | 92 | |
eb2a2fd9 KH |
93 | skb = dev_alloc_skb(sizeof(struct hdlc_header) + |
94 | sizeof(struct cisco_packet)); | |
05ff5525 | 95 | if (!skb) |
1da177e4 | 96 | return; |
05ff5525 | 97 | |
1da177e4 LT |
98 | skb_reserve(skb, 4); |
99 | cisco_hard_header(skb, dev, CISCO_KEEPALIVE, NULL, NULL, 0); | |
001aa274 | 100 | data = (struct cisco_packet *)(skb->data + 4); |
1da177e4 LT |
101 | |
102 | data->type = htonl(type); | |
abf17ffd KH |
103 | data->par1 = par1; |
104 | data->par2 = par2; | |
09640e63 | 105 | data->rel = cpu_to_be16(0xFFFF); |
1da177e4 LT |
106 | /* we will need do_div here if 1000 % HZ != 0 */ |
107 | data->time = htonl((jiffies - INITIAL_JIFFIES) * (1000 / HZ)); | |
108 | ||
eb2a2fd9 | 109 | skb_put(skb, sizeof(struct cisco_packet)); |
1da177e4 LT |
110 | skb->priority = TC_PRIO_CONTROL; |
111 | skb->dev = dev; | |
9fb030a7 | 112 | skb->protocol = htons(ETH_P_HDLC); |
c1d2bbe1 | 113 | skb_reset_network_header(skb); |
1da177e4 LT |
114 | |
115 | dev_queue_xmit(skb); | |
116 | } | |
117 | ||
ab611487 | 118 | static __be16 cisco_type_trans(struct sk_buff *skb, struct net_device *dev) |
1da177e4 | 119 | { |
001aa274 | 120 | struct hdlc_header *data = (struct hdlc_header *)skb->data; |
1da177e4 | 121 | |
eb2a2fd9 | 122 | if (skb->len < sizeof(struct hdlc_header)) |
09640e63 | 123 | return cpu_to_be16(ETH_P_HDLC); |
1da177e4 LT |
124 | |
125 | if (data->address != CISCO_MULTICAST && | |
126 | data->address != CISCO_UNICAST) | |
09640e63 | 127 | return cpu_to_be16(ETH_P_HDLC); |
1da177e4 | 128 | |
640462cb | 129 | switch (data->protocol) { |
09640e63 HH |
130 | case cpu_to_be16(ETH_P_IP): |
131 | case cpu_to_be16(ETH_P_IPX): | |
132 | case cpu_to_be16(ETH_P_IPV6): | |
eb2a2fd9 | 133 | skb_pull(skb, sizeof(struct hdlc_header)); |
1da177e4 LT |
134 | return data->protocol; |
135 | default: | |
09640e63 | 136 | return cpu_to_be16(ETH_P_HDLC); |
1da177e4 LT |
137 | } |
138 | } | |
139 | ||
1da177e4 LT |
140 | static int cisco_rx(struct sk_buff *skb) |
141 | { | |
142 | struct net_device *dev = skb->dev; | |
143 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
aff26e2f | 144 | struct cisco_state *st = state(hdlc); |
001aa274 | 145 | struct hdlc_header *data = (struct hdlc_header *)skb->data; |
eb2a2fd9 | 146 | struct cisco_packet *cisco_data; |
1da177e4 | 147 | struct in_device *in_dev; |
a144ea4b | 148 | __be32 addr, mask; |
9652041d | 149 | u32 ack; |
1da177e4 | 150 | |
eb2a2fd9 | 151 | if (skb->len < sizeof(struct hdlc_header)) |
1da177e4 LT |
152 | goto rx_error; |
153 | ||
154 | if (data->address != CISCO_MULTICAST && | |
155 | data->address != CISCO_UNICAST) | |
156 | goto rx_error; | |
157 | ||
4dfce407 | 158 | switch (ntohs(data->protocol)) { |
1da177e4 LT |
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: | |
eb2a2fd9 KH |
165 | if ((skb->len != sizeof(struct hdlc_header) + |
166 | CISCO_PACKET_LEN) && | |
167 | (skb->len != sizeof(struct hdlc_header) + | |
168 | CISCO_BIG_PACKET_LEN)) { | |
12a3bfef JP |
169 | netdev_info(dev, "Invalid length of Cisco control packet (%d bytes)\n", |
170 | skb->len); | |
1da177e4 LT |
171 | goto rx_error; |
172 | } | |
173 | ||
001aa274 | 174 | cisco_data = (struct cisco_packet *)(skb->data + sizeof |
eb2a2fd9 | 175 | (struct hdlc_header)); |
1da177e4 | 176 | |
4a20f8ec | 177 | switch (ntohl(cisco_data->type)) { |
1da177e4 | 178 | case CISCO_ADDR_REQ: /* Stolen from syncppp.c :-) */ |
95ae6b22 ED |
179 | rcu_read_lock(); |
180 | in_dev = __in_dev_get_rcu(dev); | |
1da177e4 | 181 | addr = 0; |
09640e63 | 182 | mask = ~cpu_to_be32(0); /* is the mask correct? */ |
1da177e4 LT |
183 | |
184 | if (in_dev != NULL) { | |
cb8f1478 | 185 | const struct in_ifaddr *ifa; |
1da177e4 | 186 | |
cb8f1478 | 187 | in_dev_for_each_ifa_rcu(ifa, in_dev) { |
1da177e4 | 188 | if (strcmp(dev->name, |
cb8f1478 FW |
189 | ifa->ifa_label) == 0) { |
190 | addr = ifa->ifa_local; | |
191 | mask = ifa->ifa_mask; | |
1da177e4 LT |
192 | break; |
193 | } | |
1da177e4 LT |
194 | } |
195 | ||
196 | cisco_keepalive_send(dev, CISCO_ADDR_REPLY, | |
197 | addr, mask); | |
198 | } | |
95ae6b22 | 199 | rcu_read_unlock(); |
1da177e4 LT |
200 | dev_kfree_skb_any(skb); |
201 | return NET_RX_SUCCESS; | |
202 | ||
203 | case CISCO_ADDR_REPLY: | |
12a3bfef | 204 | netdev_info(dev, "Unexpected Cisco IP address reply\n"); |
1da177e4 LT |
205 | goto rx_error; |
206 | ||
207 | case CISCO_KEEPALIVE_REQ: | |
aff26e2f KH |
208 | spin_lock(&st->lock); |
209 | st->rxseq = ntohl(cisco_data->par1); | |
9652041d KH |
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)) { | |
aff26e2f KH |
214 | st->last_poll = jiffies; |
215 | if (!st->up) { | |
1da177e4 | 216 | u32 sec, min, hrs, days; |
4e38d514 | 217 | |
1da177e4 LT |
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; | |
12a3bfef JP |
222 | netdev_info(dev, "Link up (peer uptime %ud%uh%um%us)\n", |
223 | days, hrs, min, sec); | |
c2ce9204 | 224 | netif_dormant_off(dev); |
aff26e2f | 225 | st->up = 1; |
1da177e4 LT |
226 | } |
227 | } | |
aff26e2f | 228 | spin_unlock(&st->lock); |
1da177e4 LT |
229 | |
230 | dev_kfree_skb_any(skb); | |
231 | return NET_RX_SUCCESS; | |
640462cb RM |
232 | } /* switch (keepalive type) */ |
233 | } /* switch (protocol) */ | |
1da177e4 | 234 | |
12a3bfef | 235 | netdev_info(dev, "Unsupported protocol %x\n", ntohs(data->protocol)); |
1da177e4 LT |
236 | dev_kfree_skb_any(skb); |
237 | return NET_RX_DROP; | |
238 | ||
198191c4 KH |
239 | rx_error: |
240 | dev->stats.rx_errors++; /* Mark error */ | |
1da177e4 LT |
241 | dev_kfree_skb_any(skb); |
242 | return NET_RX_DROP; | |
243 | } | |
244 | ||
d26c089e | 245 | static void cisco_timer(struct timer_list *t) |
1da177e4 | 246 | { |
d26c089e KC |
247 | struct cisco_state *st = from_timer(st, t, timer); |
248 | struct net_device *dev = st->dev; | |
1da177e4 | 249 | |
aff26e2f KH |
250 | spin_lock(&st->lock); |
251 | if (st->up && | |
252 | time_after(jiffies, st->last_poll + st->settings.timeout * HZ)) { | |
253 | st->up = 0; | |
12a3bfef | 254 | netdev_info(dev, "Link down\n"); |
c2ce9204 | 255 | netif_dormant_on(dev); |
1da177e4 LT |
256 | } |
257 | ||
aff26e2f KH |
258 | cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ, htonl(++st->txseq), |
259 | htonl(st->rxseq)); | |
aff26e2f KH |
260 | spin_unlock(&st->lock); |
261 | ||
262 | st->timer.expires = jiffies + st->settings.interval * HZ; | |
aff26e2f | 263 | add_timer(&st->timer); |
1da177e4 LT |
264 | } |
265 | ||
1da177e4 LT |
266 | static void cisco_start(struct net_device *dev) |
267 | { | |
268 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
aff26e2f KH |
269 | struct cisco_state *st = state(hdlc); |
270 | unsigned long flags; | |
271 | ||
272 | spin_lock_irqsave(&st->lock, flags); | |
9652041d | 273 | st->up = st->txseq = st->rxseq = 0; |
aff26e2f KH |
274 | spin_unlock_irqrestore(&st->lock, flags); |
275 | ||
d26c089e KC |
276 | st->dev = dev; |
277 | timer_setup(&st->timer, cisco_timer, 0); | |
aff26e2f | 278 | st->timer.expires = jiffies + HZ; /* First poll after 1 s */ |
aff26e2f | 279 | add_timer(&st->timer); |
1da177e4 LT |
280 | } |
281 | ||
1da177e4 LT |
282 | static void cisco_stop(struct net_device *dev) |
283 | { | |
284 | hdlc_device *hdlc = dev_to_hdlc(dev); | |
aff26e2f KH |
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); | |
c2ce9204 | 291 | netif_dormant_on(dev); |
9652041d | 292 | st->up = st->txseq = 0; |
aff26e2f | 293 | spin_unlock_irqrestore(&st->lock, flags); |
1da177e4 LT |
294 | } |
295 | ||
eb2a2fd9 KH |
296 | static struct hdlc_proto proto = { |
297 | .start = cisco_start, | |
298 | .stop = cisco_stop, | |
299 | .type_trans = cisco_type_trans, | |
300 | .ioctl = cisco_ioctl, | |
40d25142 | 301 | .netif_rx = cisco_rx, |
eb2a2fd9 KH |
302 | .module = THIS_MODULE, |
303 | }; | |
3b04ddde SH |
304 | |
305 | static const struct header_ops cisco_header_ops = { | |
306 | .create = cisco_hard_header, | |
307 | }; | |
4dfce407 | 308 | |
ad7eab2a | 309 | static int cisco_ioctl(struct net_device *dev, struct if_settings *ifs) |
1da177e4 | 310 | { |
ad7eab2a | 311 | cisco_proto __user *cisco_s = ifs->ifs_ifsu.cisco; |
1da177e4 LT |
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 | ||
ad7eab2a | 317 | switch (ifs->type) { |
1da177e4 | 318 | case IF_GET_PROTO: |
eb2a2fd9 KH |
319 | if (dev_to_hdlc(dev)->proto != &proto) |
320 | return -EINVAL; | |
ad7eab2a AB |
321 | ifs->type = IF_PROTO_CISCO; |
322 | if (ifs->size < size) { | |
323 | ifs->size = size; /* data size wanted */ | |
1da177e4 LT |
324 | return -ENOBUFS; |
325 | } | |
eb2a2fd9 | 326 | if (copy_to_user(cisco_s, &state(hdlc)->settings, size)) |
1da177e4 LT |
327 | return -EFAULT; |
328 | return 0; | |
329 | ||
330 | case IF_PROTO_CISCO: | |
4dfce407 | 331 | if (!capable(CAP_NET_ADMIN)) |
1da177e4 LT |
332 | return -EPERM; |
333 | ||
4dfce407 | 334 | if (dev->flags & IFF_UP) |
1da177e4 LT |
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 | ||
c1300f37 PL |
344 | result = hdlc->attach(dev, ENCODING_NRZ, |
345 | PARITY_CRC16_PR1_CCITT); | |
1da177e4 LT |
346 | if (result) |
347 | return result; | |
348 | ||
40d25142 | 349 | result = attach_hdlc_protocol(dev, &proto, |
eb2a2fd9 KH |
350 | sizeof(struct cisco_state)); |
351 | if (result) | |
352 | return result; | |
1da177e4 | 353 | |
eb2a2fd9 | 354 | memcpy(&state(hdlc)->settings, &new_settings, size); |
aff26e2f | 355 | spin_lock_init(&state(hdlc)->lock); |
3b04ddde | 356 | dev->header_ops = &cisco_header_ops; |
1a545ebe | 357 | dev->hard_header_len = sizeof(struct hdlc_header); |
1da177e4 | 358 | dev->type = ARPHRD_CISCO; |
2f8364a2 | 359 | call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev); |
c2ce9204 | 360 | netif_dormant_on(dev); |
1da177e4 LT |
361 | return 0; |
362 | } | |
363 | ||
364 | return -EINVAL; | |
365 | } | |
eb2a2fd9 | 366 | |
a1739c30 | 367 | static int __init hdlc_cisco_init(void) |
eb2a2fd9 KH |
368 | { |
369 | register_hdlc_protocol(&proto); | |
370 | return 0; | |
371 | } | |
372 | ||
a1739c30 | 373 | static void __exit hdlc_cisco_exit(void) |
eb2a2fd9 KH |
374 | { |
375 | unregister_hdlc_protocol(&proto); | |
376 | } | |
377 | ||
a1739c30 RD |
378 | module_init(hdlc_cisco_init); |
379 | module_exit(hdlc_cisco_exit); | |
eb2a2fd9 KH |
380 | |
381 | MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>"); | |
382 | MODULE_DESCRIPTION("Cisco HDLC protocol support for generic HDLC"); | |
383 | MODULE_LICENSE("GPL v2"); |