[linux.git] / net / rose / rose_link.c

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Copyright (C) Jonathan Naylor G4KLX ([email protected])
 */
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/slab.h>
#include <net/ax25.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <net/rose.h>

static void rose_ftimer_expiry(struct timer_list *);
static void rose_t0timer_expiry(struct timer_list *);

static void rose_transmit_restart_confirmation(struct rose_neigh *neigh);
static void rose_transmit_restart_request(struct rose_neigh *neigh);

void rose_start_ftimer(struct rose_neigh *neigh)
{
	del_timer(&neigh->ftimer);

	neigh->ftimer.function = rose_ftimer_expiry;
	neigh->ftimer.expires  =
		jiffies + msecs_to_jiffies(sysctl_rose_link_fail_timeout);

	add_timer(&neigh->ftimer);
}

static void rose_start_t0timer(struct rose_neigh *neigh)
{
	del_timer(&neigh->t0timer);

	neigh->t0timer.function = rose_t0timer_expiry;
	neigh->t0timer.expires  =
		jiffies + msecs_to_jiffies(sysctl_rose_restart_request_timeout);

	add_timer(&neigh->t0timer);
}

void rose_stop_ftimer(struct rose_neigh *neigh)
{
	del_timer(&neigh->ftimer);
}

void rose_stop_t0timer(struct rose_neigh *neigh)
{
	del_timer(&neigh->t0timer);
}

int rose_ftimer_running(struct rose_neigh *neigh)
{
	return timer_pending(&neigh->ftimer);
}

static int rose_t0timer_running(struct rose_neigh *neigh)
{
	return timer_pending(&neigh->t0timer);
}

static void rose_ftimer_expiry(struct timer_list *t)
{
}

static void rose_t0timer_expiry(struct timer_list *t)
{
	struct rose_neigh *neigh = from_timer(neigh, t, t0timer);

	rose_transmit_restart_request(neigh);

	neigh->dce_mode = 0;

	rose_start_t0timer(neigh);
}

/*
 *	Interface to ax25_send_frame. Changes my level 2 callsign depending
 *	on whether we have a global ROSE callsign or use the default port
 *	callsign.
 */
static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh)
{
	ax25_address *rose_call;
	ax25_cb *ax25s;

	if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
		rose_call = (ax25_address *)neigh->dev->dev_addr;
	else
		rose_call = &rose_callsign;

	ax25s = neigh->ax25;
	neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
	if (ax25s)
		ax25_cb_put(ax25s);

	return neigh->ax25 != NULL;
}

/*
 *	Interface to ax25_link_up. Changes my level 2 callsign depending
 *	on whether we have a global ROSE callsign or use the default port
 *	callsign.
 */
static int rose_link_up(struct rose_neigh *neigh)
{
	ax25_address *rose_call;
	ax25_cb *ax25s;

	if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
		rose_call = (ax25_address *)neigh->dev->dev_addr;
	else
		rose_call = &rose_callsign;

	ax25s = neigh->ax25;
	neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
	if (ax25s)
		ax25_cb_put(ax25s);

	return neigh->ax25 != NULL;
}

/*
 *	This handles all restart and diagnostic frames.
 */
void rose_link_rx_restart(struct sk_buff *skb, struct rose_neigh *neigh, unsigned short frametype)
{
	struct sk_buff *skbn;

	switch (frametype) {
	case ROSE_RESTART_REQUEST:
		rose_stop_t0timer(neigh);
		neigh->restarted = 1;
		neigh->dce_mode  = (skb->data[3] == ROSE_DTE_ORIGINATED);
		rose_transmit_restart_confirmation(neigh);
		break;

	case ROSE_RESTART_CONFIRMATION:
		rose_stop_t0timer(neigh);
		neigh->restarted = 1;
		break;

	case ROSE_DIAGNOSTIC:
		pr_warn("ROSE: received diagnostic #%d - %3ph\n", skb->data[3],
			skb->data + 4);
		break;

	default:
		printk(KERN_WARNING "ROSE: received unknown %02X with LCI 000\n", frametype);
		break;
	}

	if (neigh->restarted) {
		while ((skbn = skb_dequeue(&neigh->queue)) != NULL)
			if (!rose_send_frame(skbn, neigh))
				kfree_skb(skbn);
	}
}

/*
 *	This routine is called when a Restart Request is needed
 */
static void rose_transmit_restart_request(struct rose_neigh *neigh)
{
	struct sk_buff *skb;
	unsigned char *dptr;
	int len;

	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;

	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
		return;

	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);

	dptr = skb_put(skb, ROSE_MIN_LEN + 3);

	*dptr++ = AX25_P_ROSE;
	*dptr++ = ROSE_GFI;
	*dptr++ = 0x00;
	*dptr++ = ROSE_RESTART_REQUEST;
	*dptr++ = ROSE_DTE_ORIGINATED;
	*dptr++ = 0;

	if (!rose_send_frame(skb, neigh))
		kfree_skb(skb);
}

/*
 * This routine is called when a Restart Confirmation is needed
 */
static void rose_transmit_restart_confirmation(struct rose_neigh *neigh)
{
	struct sk_buff *skb;
	unsigned char *dptr;
	int len;

	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1;

	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
		return;

	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);

	dptr = skb_put(skb, ROSE_MIN_LEN + 1);

	*dptr++ = AX25_P_ROSE;
	*dptr++ = ROSE_GFI;
	*dptr++ = 0x00;
	*dptr++ = ROSE_RESTART_CONFIRMATION;

	if (!rose_send_frame(skb, neigh))
		kfree_skb(skb);
}

/*
 * This routine is called when a Clear Request is needed outside of the context
 * of a connected socket.
 */
void rose_transmit_clear_request(struct rose_neigh *neigh, unsigned int lci, unsigned char cause, unsigned char diagnostic)
{
	struct sk_buff *skb;
	unsigned char *dptr;
	int len;

	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;

	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
		return;

	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);

	dptr = skb_put(skb, ROSE_MIN_LEN + 3);

	*dptr++ = AX25_P_ROSE;
	*dptr++ = ((lci >> 8) & 0x0F) | ROSE_GFI;
	*dptr++ = ((lci >> 0) & 0xFF);
	*dptr++ = ROSE_CLEAR_REQUEST;
	*dptr++ = cause;
	*dptr++ = diagnostic;

	if (!rose_send_frame(skb, neigh))
		kfree_skb(skb);
}

void rose_transmit_link(struct sk_buff *skb, struct rose_neigh *neigh)
{
	unsigned char *dptr;

	if (neigh->loopback) {
		rose_loopback_queue(skb, neigh);
		return;
	}

	if (!rose_link_up(neigh))
		neigh->restarted = 0;

	dptr = skb_push(skb, 1);
	*dptr++ = AX25_P_ROSE;

	if (neigh->restarted) {
		if (!rose_send_frame(skb, neigh))
			kfree_skb(skb);
	} else {
		skb_queue_tail(&neigh->queue, skb);

		if (!rose_t0timer_running(neigh)) {
			rose_transmit_restart_request(neigh);
			neigh->dce_mode = 0;
			rose_start_t0timer(neigh);
		}
	}
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* This program is free software; you can redistribute it and/or modify
	3	* it under the terms of the GNU General Public License as published by
	4	* the Free Software Foundation; either version 2 of the License, or
	5	* (at your option) any later version.
	6	*
	7	* Copyright (C) Jonathan Naylor G4KLX ([email protected])
	8	*/
	9	#include <linux/errno.h>
	10	#include <linux/types.h>
	11	#include <linux/socket.h>
	12	#include <linux/in.h>
	13	#include <linux/kernel.h>
	14	#include <linux/jiffies.h>
	15	#include <linux/timer.h>
	16	#include <linux/string.h>
	17	#include <linux/sockios.h>
	18	#include <linux/net.h>
5a0e3ad6	19	#include <linux/slab.h>
1da177e4 LT	20	#include <net/ax25.h>
	21	#include <linux/inet.h>
	22	#include <linux/netdevice.h>
	23	#include <linux/skbuff.h>
	24	#include <net/sock.h>
1da177e4 LT	25	#include <linux/fcntl.h>
	26	#include <linux/mm.h>
	27	#include <linux/interrupt.h>
1da177e4 LT	28	#include <net/rose.h>
1da177e4 LT	29
4966babd KC	30	static void rose_ftimer_expiry(struct timer_list *);
4966babd KC	31	static void rose_t0timer_expiry(struct timer_list *);
1da177e4 LT	32
	33	static void rose_transmit_restart_confirmation(struct rose_neigh *neigh);
	34	static void rose_transmit_restart_request(struct rose_neigh *neigh);
	35
	36	void rose_start_ftimer(struct rose_neigh *neigh)
	37	{
	38	del_timer(&neigh->ftimer);
	39
841b86f3	40	neigh->ftimer.function = rose_ftimer_expiry;
82e84249 RB	41	neigh->ftimer.expires =
82e84249 RB	42	jiffies + msecs_to_jiffies(sysctl_rose_link_fail_timeout);
1da177e4 LT	43
	44	add_timer(&neigh->ftimer);
	45	}
	46
	47	static void rose_start_t0timer(struct rose_neigh *neigh)
	48	{
	49	del_timer(&neigh->t0timer);
	50
841b86f3	51	neigh->t0timer.function = rose_t0timer_expiry;
82e84249 RB	52	neigh->t0timer.expires =
82e84249 RB	53	jiffies + msecs_to_jiffies(sysctl_rose_restart_request_timeout);
1da177e4 LT	54
	55	add_timer(&neigh->t0timer);
	56	}
	57
	58	void rose_stop_ftimer(struct rose_neigh *neigh)
	59	{
	60	del_timer(&neigh->ftimer);
	61	}
	62
	63	void rose_stop_t0timer(struct rose_neigh *neigh)
	64	{
	65	del_timer(&neigh->t0timer);
	66	}
	67
	68	int rose_ftimer_running(struct rose_neigh *neigh)
	69	{
	70	return timer_pending(&neigh->ftimer);
	71	}
	72
	73	static int rose_t0timer_running(struct rose_neigh *neigh)
	74	{
	75	return timer_pending(&neigh->t0timer);
	76	}
	77
4966babd	78	static void rose_ftimer_expiry(struct timer_list *t)
1da177e4 LT	79	{
	80	}
	81
4966babd	82	static void rose_t0timer_expiry(struct timer_list *t)
1da177e4	83	{
4966babd	84	struct rose_neigh *neigh = from_timer(neigh, t, t0timer);
1da177e4 LT	85
	86	rose_transmit_restart_request(neigh);
	87
	88	neigh->dce_mode = 0;
	89
	90	rose_start_t0timer(neigh);
	91	}
	92
	93	/*
	94	* Interface to ax25_send_frame. Changes my level 2 callsign depending
	95	* on whether we have a global ROSE callsign or use the default port
	96	* callsign.
	97	*/
	98	static int rose_send_frame(struct sk_buff skb, struct rose_neigh neigh)
	99	{
	100	ax25_address *rose_call;
d00c362f	101	ax25_cb *ax25s;
1da177e4 LT	102
	103	if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
	104	rose_call = (ax25_address *)neigh->dev->dev_addr;
	105	else
	106	rose_call = &rose_callsign;
	107
d00c362f	108	ax25s = neigh->ax25;
1da177e4	109	neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
d00c362f JP	110	if (ax25s)
d00c362f JP	111	ax25_cb_put(ax25s);
1da177e4	112
a02cec21	113	return neigh->ax25 != NULL;
1da177e4 LT	114	}
	115
	116	/*
	117	* Interface to ax25_link_up. Changes my level 2 callsign depending
	118	* on whether we have a global ROSE callsign or use the default port
	119	* callsign.
	120	*/
	121	static int rose_link_up(struct rose_neigh *neigh)
	122	{
	123	ax25_address *rose_call;
d00c362f	124	ax25_cb *ax25s;
1da177e4 LT	125
	126	if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
	127	rose_call = (ax25_address *)neigh->dev->dev_addr;
	128	else
	129	rose_call = &rose_callsign;
	130
d00c362f	131	ax25s = neigh->ax25;
1da177e4	132	neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
d00c362f JP	133	if (ax25s)
d00c362f JP	134	ax25_cb_put(ax25s);
1da177e4	135
a02cec21	136	return neigh->ax25 != NULL;
1da177e4 LT	137	}
	138
	139	/*
	140	* This handles all restart and diagnostic frames.
	141	*/
	142	void rose_link_rx_restart(struct sk_buff skb, struct rose_neigh neigh, unsigned short frametype)
	143	{
	144	struct sk_buff *skbn;
	145
	146	switch (frametype) {
	147	case ROSE_RESTART_REQUEST:
	148	rose_stop_t0timer(neigh);
	149	neigh->restarted = 1;
	150	neigh->dce_mode = (skb->data[3] == ROSE_DTE_ORIGINATED);
	151	rose_transmit_restart_confirmation(neigh);
	152	break;
	153
	154	case ROSE_RESTART_CONFIRMATION:
	155	rose_stop_t0timer(neigh);
	156	neigh->restarted = 1;
	157	break;
	158
	159	case ROSE_DIAGNOSTIC:
13aa3463 AS	160	pr_warn("ROSE: received diagnostic #%d - %3ph\n", skb->data[3],
13aa3463 AS	161	skb->data + 4);
1da177e4 LT	162	break;
	163
	164	default:
	165	printk(KERN_WARNING "ROSE: received unknown %02X with LCI 000\n", frametype);
	166	break;
	167	}
	168
	169	if (neigh->restarted) {
	170	while ((skbn = skb_dequeue(&neigh->queue)) != NULL)
	171	if (!rose_send_frame(skbn, neigh))
	172	kfree_skb(skbn);
	173	}
	174	}
	175
	176	/*
	177	* This routine is called when a Restart Request is needed
	178	*/
	179	static void rose_transmit_restart_request(struct rose_neigh *neigh)
	180	{
	181	struct sk_buff *skb;
	182	unsigned char *dptr;
	183	int len;
	184
	185	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
	186
	187	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
	188	return;
	189
	190	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
	191
	192	dptr = skb_put(skb, ROSE_MIN_LEN + 3);
	193
	194	*dptr++ = AX25_P_ROSE;
	195	*dptr++ = ROSE_GFI;
	196	*dptr++ = 0x00;
	197	*dptr++ = ROSE_RESTART_REQUEST;
	198	*dptr++ = ROSE_DTE_ORIGINATED;
	199	*dptr++ = 0;
	200
	201	if (!rose_send_frame(skb, neigh))
	202	kfree_skb(skb);
	203	}
	204
	205	/*
	206	* This routine is called when a Restart Confirmation is needed
	207	*/
	208	static void rose_transmit_restart_confirmation(struct rose_neigh *neigh)
	209	{
	210	struct sk_buff *skb;
	211	unsigned char *dptr;
	212	int len;
	213
	214	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1;
	215
	216	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
	217	return;
	218
	219	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
	220
	221	dptr = skb_put(skb, ROSE_MIN_LEN + 1);
	222
	223	*dptr++ = AX25_P_ROSE;
	224	*dptr++ = ROSE_GFI;
	225	*dptr++ = 0x00;
226	*dptr++ = ROSE_RESTART_CONFIRMATION;
227
228	if (!rose_send_frame(skb, neigh))
229	kfree_skb(skb);
230	}
231
232	/*
233	* This routine is called when a Clear Request is needed outside of the context
234	* of a connected socket.
235	*/
236	void rose_transmit_clear_request(struct rose_neigh *neigh, unsigned int lci, unsigned char cause, unsigned char diagnostic)
237	{
238	struct sk_buff *skb;
239	unsigned char *dptr;
240	int len;
241
242	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
243
244	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
245	return;
246
247	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
248
249	dptr = skb_put(skb, ROSE_MIN_LEN + 3);
250
251	*dptr++ = AX25_P_ROSE;
252	*dptr++ = ((lci >> 8) & 0x0F) \| ROSE_GFI;
253	*dptr++ = ((lci >> 0) & 0xFF);
254	*dptr++ = ROSE_CLEAR_REQUEST;
255	*dptr++ = cause;
256	*dptr++ = diagnostic;
257
258	if (!rose_send_frame(skb, neigh))
259	kfree_skb(skb);
260	}
261
262	void rose_transmit_link(struct sk_buff skb, struct rose_neigh neigh)
263	{
264	unsigned char *dptr;
265
1da177e4 LT	266	if (neigh->loopback) {
	267	rose_loopback_queue(skb, neigh);
	268	return;
	269	}
	270
	271	if (!rose_link_up(neigh))
	272	neigh->restarted = 0;
	273
	274	dptr = skb_push(skb, 1);
	275	*dptr++ = AX25_P_ROSE;
	276
	277	if (neigh->restarted) {
	278	if (!rose_send_frame(skb, neigh))
	279	kfree_skb(skb);
	280	} else {
	281	skb_queue_tail(&neigh->queue, skb);
	282
	283	if (!rose_t0timer_running(neigh)) {
	284	rose_transmit_restart_request(neigh);
	285	neigh->dce_mode = 0;
	286	rose_start_t0timer(neigh);
	287	}
	288	}
	289	}