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
40static void rose_ftimer_expiry(unsigned long);
41static void rose_t0timer_expiry(unsigned long);
42
43void 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
54void 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
65void rose_stop_ftimer(struct rose_neigh *neigh)
66{
67	del_timer(&neigh->ftimer);
68}
69
70void rose_stop_t0timer(struct rose_neigh *neigh)
71{
72	del_timer(&neigh->t0timer);
73}
74
75int rose_ftimer_running(struct rose_neigh *neigh)
76{
77	return timer_pending(&neigh->ftimer);
78}
79
80int rose_t0timer_running(struct rose_neigh *neigh)
81{
82	return timer_pending(&neigh->t0timer);
83}
84
85static void rose_ftimer_expiry(unsigned long param)
86{
87}
88
89static 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 */
105static 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 */
124static 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 */
141void 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 */
177void 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 */
206void 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 */
233void 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 */
262void 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
309void rose_transmit_link(struct sk_buff *skb, struct rose_neigh *neigh)
310{
311	unsigned char *dptr;
312
313
314	if (neigh->loopback) {
315		rose_loopback_queue(skb, neigh);
316		return;
317	}
318
319	if (!rose_link_up(neigh))
320		neigh->restarted = 0;
321
322	dptr = skb_push(skb, 1);
323	*dptr++ = AX25_P_ROSE;
324
325	if (neigh->restarted) {
326		if (!rose_send_frame(skb, neigh))
327			kfree_skb(skb);
328	} else {
329		skb_queue_tail(&neigh->queue, skb);
330
331		if (!rose_t0timer_running(neigh)) {
332			rose_transmit_restart_request(neigh);
333			neigh->dce_mode = 0;
334			rose_start_t0timer(neigh);
335		}
336	}
337}
338