1 /*
2  *	ROSE release 003
3  *
4  *	This code REQUIRES 2.1.15 or higher/ NET3.038
5  *
6  *	This module:
7  *		This module is free software; you can redistribute it and/or
8  *		modify it under the terms of the GNU General Public License
9  *		as published by the Free Software Foundation; either version
10  *		2 of the License, or (at your option) any later version.
11  *
12  *	History
13  *	ROSE 001	Jonathan(G4KLX)	Cloned from rose_timer.c
14  *	ROSE 003	Jonathan(G4KLX)	New timer architecture.
15  */
16 
17 #include <linux/errno.h>
18 #include <linux/types.h>
19 #include <linux/socket.h>
20 #include <linux/in.h>
21 #include <linux/kernel.h>
22 #include <linux/sched.h>
23 #include <linux/timer.h>
24 #include <linux/string.h>
25 #include <linux/sockios.h>
26 #include <linux/net.h>
27 #include <net/ax25.h>
28 #include <linux/inet.h>
29 #include <linux/netdevice.h>
30 #include <linux/skbuff.h>
31 #include <net/sock.h>
32 #include <asm/segment.h>
33 #include <asm/system.h>
34 #include <linux/fcntl.h>
35 #include <linux/mm.h>
36 #include <linux/interrupt.h>
37 #include <linux/netfilter.h>
38 #include <net/rose.h>
39 
40 static void rose_ftimer_expiry(unsigned long);
41 static void rose_t0timer_expiry(unsigned long);
42 
rose_start_ftimer(struct rose_neigh * neigh)43 void rose_start_ftimer(struct rose_neigh *neigh)
44 {
45 	del_timer(&neigh->ftimer);
46 
47 	neigh->ftimer.data     = (unsigned long)neigh;
48 	neigh->ftimer.function = &rose_ftimer_expiry;
49 	neigh->ftimer.expires  = jiffies + sysctl_rose_link_fail_timeout;
50 
51 	add_timer(&neigh->ftimer);
52 }
53 
rose_start_t0timer(struct rose_neigh * neigh)54 void rose_start_t0timer(struct rose_neigh *neigh)
55 {
56 	del_timer(&neigh->t0timer);
57 
58 	neigh->t0timer.data     = (unsigned long)neigh;
59 	neigh->t0timer.function = &rose_t0timer_expiry;
60 	neigh->t0timer.expires  = jiffies + sysctl_rose_restart_request_timeout;
61 
62 	add_timer(&neigh->t0timer);
63 }
64 
rose_stop_ftimer(struct rose_neigh * neigh)65 void rose_stop_ftimer(struct rose_neigh *neigh)
66 {
67 	del_timer(&neigh->ftimer);
68 }
69 
rose_stop_t0timer(struct rose_neigh * neigh)70 void rose_stop_t0timer(struct rose_neigh *neigh)
71 {
72 	del_timer(&neigh->t0timer);
73 }
74 
rose_ftimer_running(struct rose_neigh * neigh)75 int rose_ftimer_running(struct rose_neigh *neigh)
76 {
77 	return timer_pending(&neigh->ftimer);
78 }
79 
rose_t0timer_running(struct rose_neigh * neigh)80 int rose_t0timer_running(struct rose_neigh *neigh)
81 {
82 	return timer_pending(&neigh->t0timer);
83 }
84 
rose_ftimer_expiry(unsigned long param)85 static void rose_ftimer_expiry(unsigned long param)
86 {
87 }
88 
rose_t0timer_expiry(unsigned long param)89 static void rose_t0timer_expiry(unsigned long param)
90 {
91 	struct rose_neigh *neigh = (struct rose_neigh *)param;
92 
93 	rose_transmit_restart_request(neigh);
94 
95 	neigh->dce_mode = 0;
96 
97 	rose_start_t0timer(neigh);
98 }
99 
100 /*
101  *	Interface to ax25_send_frame. Changes my level 2 callsign depending
102  *	on whether we have a global ROSE callsign or use the default port
103  *	callsign.
104  */
rose_send_frame(struct sk_buff * skb,struct rose_neigh * neigh)105 static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh)
106 {
107 	ax25_address *rose_call;
108 
109 	if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
110 		rose_call = (ax25_address *)neigh->dev->dev_addr;
111 	else
112 		rose_call = &rose_callsign;
113 
114 	neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
115 
116 	return (neigh->ax25 != NULL);
117 }
118 
119 /*
120  *	Interface to ax25_link_up. Changes my level 2 callsign depending
121  *	on whether we have a global ROSE callsign or use the default port
122  *	callsign.
123  */
rose_link_up(struct rose_neigh * neigh)124 static int rose_link_up(struct rose_neigh *neigh)
125 {
126 	ax25_address *rose_call;
127 
128 	if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
129 		rose_call = (ax25_address *)neigh->dev->dev_addr;
130 	else
131 		rose_call = &rose_callsign;
132 
133 	neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
134 
135 	return (neigh->ax25 != NULL);
136 }
137 
138 /*
139  *	This handles all restart and diagnostic frames.
140  */
rose_link_rx_restart(struct sk_buff * skb,struct rose_neigh * neigh,unsigned short frametype)141 void rose_link_rx_restart(struct sk_buff *skb, struct rose_neigh *neigh, unsigned short frametype)
142 {
143 	struct sk_buff *skbn;
144 
145 	switch (frametype) {
146 		case ROSE_RESTART_REQUEST:
147 			rose_stop_t0timer(neigh);
148 			neigh->restarted = 1;
149 			neigh->dce_mode  = (skb->data[3] == ROSE_DTE_ORIGINATED);
150 			rose_transmit_restart_confirmation(neigh);
151 			break;
152 
153 		case ROSE_RESTART_CONFIRMATION:
154 			rose_stop_t0timer(neigh);
155 			neigh->restarted = 1;
156 			break;
157 
158 		case ROSE_DIAGNOSTIC:
159 			printk(KERN_WARNING "ROSE: received diagnostic #%d - %02X %02X %02X\n", skb->data[3], skb->data[4], skb->data[5], skb->data[6]);
160 			break;
161 
162 		default:
163 			printk(KERN_WARNING "ROSE: received unknown %02X with LCI 000\n", frametype);
164 			break;
165 	}
166 
167 	if (neigh->restarted) {
168 		while ((skbn = skb_dequeue(&neigh->queue)) != NULL)
169 			if (!rose_send_frame(skbn, neigh))
170 				kfree_skb(skbn);
171 	}
172 }
173 
174 /*
175  *	This routine is called when a Restart Request is needed
176  */
rose_transmit_restart_request(struct rose_neigh * neigh)177 void rose_transmit_restart_request(struct rose_neigh *neigh)
178 {
179 	struct sk_buff *skb;
180 	unsigned char *dptr;
181 	int len;
182 
183 	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
184 
185 	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
186 		return;
187 
188 	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
189 
190 	dptr = skb_put(skb, ROSE_MIN_LEN + 3);
191 
192 	*dptr++ = AX25_P_ROSE;
193 	*dptr++ = ROSE_GFI;
194 	*dptr++ = 0x00;
195 	*dptr++ = ROSE_RESTART_REQUEST;
196 	*dptr++ = ROSE_DTE_ORIGINATED;
197 	*dptr++ = 0;
198 
199 	if (!rose_send_frame(skb, neigh))
200 		kfree_skb(skb);
201 }
202 
203 /*
204  * This routine is called when a Restart Confirmation is needed
205  */
rose_transmit_restart_confirmation(struct rose_neigh * neigh)206 void rose_transmit_restart_confirmation(struct rose_neigh *neigh)
207 {
208 	struct sk_buff *skb;
209 	unsigned char *dptr;
210 	int len;
211 
212 	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1;
213 
214 	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
215 		return;
216 
217 	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
218 
219 	dptr = skb_put(skb, ROSE_MIN_LEN + 1);
220 
221 	*dptr++ = AX25_P_ROSE;
222 	*dptr++ = ROSE_GFI;
223 	*dptr++ = 0x00;
224 	*dptr++ = ROSE_RESTART_CONFIRMATION;
225 
226 	if (!rose_send_frame(skb, neigh))
227 		kfree_skb(skb);
228 }
229 
230 /*
231  * This routine is called when a Diagnostic is required.
232  */
rose_transmit_diagnostic(struct rose_neigh * neigh,unsigned char diag)233 void rose_transmit_diagnostic(struct rose_neigh *neigh, unsigned char diag)
234 {
235 	struct sk_buff *skb;
236 	unsigned char *dptr;
237 	int len;
238 
239 	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 2;
240 
241 	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
242 		return;
243 
244 	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
245 
246 	dptr = skb_put(skb, ROSE_MIN_LEN + 2);
247 
248 	*dptr++ = AX25_P_ROSE;
249 	*dptr++ = ROSE_GFI;
250 	*dptr++ = 0x00;
251 	*dptr++ = ROSE_DIAGNOSTIC;
252 	*dptr++ = diag;
253 
254 	if (!rose_send_frame(skb, neigh))
255 		kfree_skb(skb);
256 }
257 
258 /*
259  * This routine is called when a Clear Request is needed outside of the context
260  * of a connected socket.
261  */
rose_transmit_clear_request(struct rose_neigh * neigh,unsigned int lci,unsigned char cause,unsigned char diagnostic)262 void rose_transmit_clear_request(struct rose_neigh *neigh, unsigned int lci, unsigned char cause, unsigned char diagnostic)
263 {
264 	struct sk_buff *skb;
265 	unsigned char *dptr;
266 	int len;
267 	struct net_device *first;
268 	int faclen = 0;
269 
270 	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
271 
272 	first = rose_dev_first();
273 	if (first)
274 		faclen = 6 + AX25_ADDR_LEN + 3 + ROSE_ADDR_LEN;
275 
276 	if ((skb = alloc_skb(len + faclen, GFP_ATOMIC)) == NULL)
277 		return;
278 
279 	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
280 
281 	dptr = skb_put(skb, ROSE_MIN_LEN + 3 + faclen);
282 
283 	*dptr++ = AX25_P_ROSE;
284 	*dptr++ = ((lci >> 8) & 0x0F) | ROSE_GFI;
285 	*dptr++ = ((lci >> 0) & 0xFF);
286 	*dptr++ = ROSE_CLEAR_REQUEST;
287 	*dptr++ = cause;
288 	*dptr++ = diagnostic;
289 
290 	if (first) {
291 		*dptr++ = 0x00;		/* Address length */
292 		*dptr++ = 4 + AX25_ADDR_LEN + 3 + ROSE_ADDR_LEN; /* Facilities length */
293 		*dptr++ = 0;
294 		*dptr++ = FAC_NATIONAL;
295 		*dptr++ = FAC_NATIONAL_FAIL_CALL;
296 		*dptr++ = AX25_ADDR_LEN;
297 		memcpy(dptr, &rose_callsign, AX25_ADDR_LEN);
298 		dptr += AX25_ADDR_LEN;
299 		*dptr++ = FAC_NATIONAL_FAIL_ADD;
300 		*dptr++ = ROSE_ADDR_LEN + 1;
301 		*dptr++ = ROSE_ADDR_LEN * 2;
302 		memcpy(dptr, first->dev_addr, ROSE_ADDR_LEN);
303 	}
304 
305 	if (!rose_send_frame(skb, neigh))
306 		kfree_skb(skb);
307 }
308 
rose_transmit_link(struct sk_buff * skb,struct rose_neigh * neigh)309 void rose_transmit_link(struct sk_buff *skb, struct rose_neigh *neigh)
310 {
311 	unsigned char *dptr;
312 
313 #if 0
314 	if (call_fw_firewall(PF_ROSE, skb->dev, skb->data, NULL, &skb) != FW_ACCEPT) {
315 		kfree_skb(skb);
316 		return;
317 	}
318 #endif
319 
320 	if (neigh->loopback) {
321 		rose_loopback_queue(skb, neigh);
322 		return;
323 	}
324 
325 	if (!rose_link_up(neigh))
326 		neigh->restarted = 0;
327 
328 	dptr = skb_push(skb, 1);
329 	*dptr++ = AX25_P_ROSE;
330 
331 	if (neigh->restarted) {
332 		if (!rose_send_frame(skb, neigh))
333 			kfree_skb(skb);
334 	} else {
335 		skb_queue_tail(&neigh->queue, skb);
336 
337 		if (!rose_t0timer_running(neigh)) {
338 			rose_transmit_restart_request(neigh);
339 			neigh->dce_mode = 0;
340 			rose_start_t0timer(neigh);
341 		}
342 	}
343 }
344