[mirror_ubuntu-zesty-kernel.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 (g4klx@g4klx.demon.co.uk)
 */
#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(unsigned long);
static void rose_t0timer_expiry(unsigned long);

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.data     = (unsigned long)neigh;
	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.data     = (unsigned long)neigh;
	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(unsigned long param)
{
}

static void rose_t0timer_expiry(unsigned long param)
{
	struct rose_neigh *neigh = (struct rose_neigh *)param;

	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 (g4klx@g4klx.demon.co.uk)
	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>
	29
	30	static void rose_ftimer_expiry(unsigned long);
	31	static void rose_t0timer_expiry(unsigned long);
	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
	40	neigh->ftimer.data = (unsigned long)neigh;
	41	neigh->ftimer.function = &rose_ftimer_expiry;
82e84249 RB	42	neigh->ftimer.expires =
82e84249 RB	43	jiffies + msecs_to_jiffies(sysctl_rose_link_fail_timeout);
1da177e4 LT	44
	45	add_timer(&neigh->ftimer);
	46	}
	47
	48	static void rose_start_t0timer(struct rose_neigh *neigh)
	49	{
	50	del_timer(&neigh->t0timer);
	51
	52	neigh->t0timer.data = (unsigned long)neigh;
	53	neigh->t0timer.function = &rose_t0timer_expiry;
82e84249 RB	54	neigh->t0timer.expires =
82e84249 RB	55	jiffies + msecs_to_jiffies(sysctl_rose_restart_request_timeout);
1da177e4 LT	56
	57	add_timer(&neigh->t0timer);
	58	}
	59
	60	void rose_stop_ftimer(struct rose_neigh *neigh)
	61	{
	62	del_timer(&neigh->ftimer);
	63	}
	64
	65	void rose_stop_t0timer(struct rose_neigh *neigh)
	66	{
	67	del_timer(&neigh->t0timer);
	68	}
	69
	70	int rose_ftimer_running(struct rose_neigh *neigh)
	71	{
	72	return timer_pending(&neigh->ftimer);
	73	}
	74
	75	static int rose_t0timer_running(struct rose_neigh *neigh)
	76	{
	77	return timer_pending(&neigh->t0timer);
	78	}
	79
	80	static void rose_ftimer_expiry(unsigned long param)
	81	{
	82	}
	83
	84	static void rose_t0timer_expiry(unsigned long param)
	85	{
	86	struct rose_neigh neigh = (struct rose_neigh )param;
	87
	88	rose_transmit_restart_request(neigh);
	89
	90	neigh->dce_mode = 0;
	91
	92	rose_start_t0timer(neigh);
	93	}
	94
	95	/*
	96	* Interface to ax25_send_frame. Changes my level 2 callsign depending
	97	* on whether we have a global ROSE callsign or use the default port
	98	* callsign.
	99	*/
	100	static int rose_send_frame(struct sk_buff skb, struct rose_neigh neigh)
	101	{
	102	ax25_address *rose_call;
d00c362f	103	ax25_cb *ax25s;
1da177e4 LT	104
	105	if (ax25cmp(&rose_callsign, &null_ax25_address) == 0)
	106	rose_call = (ax25_address *)neigh->dev->dev_addr;
	107	else
	108	rose_call = &rose_callsign;
	109
d00c362f	110	ax25s = neigh->ax25;
1da177e4	111	neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
d00c362f JP	112	if (ax25s)
d00c362f JP	113	ax25_cb_put(ax25s);
1da177e4	114
a02cec21	115	return neigh->ax25 != NULL;
1da177e4 LT	116	}
	117
	118	/*
	119	* Interface to ax25_link_up. Changes my level 2 callsign depending
	120	* on whether we have a global ROSE callsign or use the default port
	121	* callsign.
	122	*/
	123	static int rose_link_up(struct rose_neigh *neigh)
	124	{
	125	ax25_address *rose_call;
d00c362f	126	ax25_cb *ax25s;
1da177e4 LT	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
d00c362f	133	ax25s = neigh->ax25;
1da177e4	134	neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev);
d00c362f JP	135	if (ax25s)
d00c362f JP	136	ax25_cb_put(ax25s);
1da177e4	137
a02cec21	138	return neigh->ax25 != NULL;
1da177e4 LT	139	}
	140
	141	/*
	142	* This handles all restart and diagnostic frames.
	143	*/
	144	void rose_link_rx_restart(struct sk_buff skb, struct rose_neigh neigh, unsigned short frametype)
	145	{
	146	struct sk_buff *skbn;
	147
	148	switch (frametype) {
	149	case ROSE_RESTART_REQUEST:
	150	rose_stop_t0timer(neigh);
	151	neigh->restarted = 1;
	152	neigh->dce_mode = (skb->data[3] == ROSE_DTE_ORIGINATED);
	153	rose_transmit_restart_confirmation(neigh);
	154	break;
	155
	156	case ROSE_RESTART_CONFIRMATION:
	157	rose_stop_t0timer(neigh);
	158	neigh->restarted = 1;
	159	break;
	160
	161	case ROSE_DIAGNOSTIC:
13aa3463 AS	162	pr_warn("ROSE: received diagnostic #%d - %3ph\n", skb->data[3],
13aa3463 AS	163	skb->data + 4);
1da177e4 LT	164	break;
	165
	166	default:
	167	printk(KERN_WARNING "ROSE: received unknown %02X with LCI 000\n", frametype);
	168	break;
	169	}
	170
	171	if (neigh->restarted) {
	172	while ((skbn = skb_dequeue(&neigh->queue)) != NULL)
	173	if (!rose_send_frame(skbn, neigh))
	174	kfree_skb(skbn);
	175	}
	176	}
	177
	178	/*
	179	* This routine is called when a Restart Request is needed
	180	*/
	181	static void rose_transmit_restart_request(struct rose_neigh *neigh)
	182	{
	183	struct sk_buff *skb;
	184	unsigned char *dptr;
	185	int len;
	186
	187	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
	188
	189	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
	190	return;
	191
	192	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
	193
	194	dptr = skb_put(skb, ROSE_MIN_LEN + 3);
	195
	196	*dptr++ = AX25_P_ROSE;
	197	*dptr++ = ROSE_GFI;
	198	*dptr++ = 0x00;
	199	*dptr++ = ROSE_RESTART_REQUEST;
	200	*dptr++ = ROSE_DTE_ORIGINATED;
	201	*dptr++ = 0;
	202
	203	if (!rose_send_frame(skb, neigh))
	204	kfree_skb(skb);
	205	}
	206
	207	/*
	208	* This routine is called when a Restart Confirmation is needed
	209	*/
	210	static void rose_transmit_restart_confirmation(struct rose_neigh *neigh)
	211	{
	212	struct sk_buff *skb;
	213	unsigned char *dptr;
	214	int len;
	215
	216	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1;
	217
	218	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
	219	return;
	220
	221	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
	222
	223	dptr = skb_put(skb, ROSE_MIN_LEN + 1);
	224
	225	*dptr++ = AX25_P_ROSE;
	226	*dptr++ = ROSE_GFI;
	227	*dptr++ = 0x00;
228	*dptr++ = ROSE_RESTART_CONFIRMATION;
229
230	if (!rose_send_frame(skb, neigh))
231	kfree_skb(skb);
232	}
233
234	/*
235	* This routine is called when a Clear Request is needed outside of the context
236	* of a connected socket.
237	*/
238	void rose_transmit_clear_request(struct rose_neigh *neigh, unsigned int lci, unsigned char cause, unsigned char diagnostic)
239	{
240	struct sk_buff *skb;
241	unsigned char *dptr;
242	int len;
243
244	len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3;
245
246	if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL)
247	return;
248
249	skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN);
250
251	dptr = skb_put(skb, ROSE_MIN_LEN + 3);
252
253	*dptr++ = AX25_P_ROSE;
254	*dptr++ = ((lci >> 8) & 0x0F) \| ROSE_GFI;
255	*dptr++ = ((lci >> 0) & 0xFF);
256	*dptr++ = ROSE_CLEAR_REQUEST;
257	*dptr++ = cause;
258	*dptr++ = diagnostic;
259
260	if (!rose_send_frame(skb, neigh))
261	kfree_skb(skb);
262	}
263
264	void rose_transmit_link(struct sk_buff skb, struct rose_neigh neigh)
265	{
266	unsigned char *dptr;
267
1da177e4 LT	268	if (neigh->loopback) {
	269	rose_loopback_queue(skb, neigh);
	270	return;
	271	}
	272
	273	if (!rose_link_up(neigh))
	274	neigh->restarted = 0;
	275
	276	dptr = skb_push(skb, 1);
	277	*dptr++ = AX25_P_ROSE;
	278
	279	if (neigh->restarted) {
	280	if (!rose_send_frame(skb, neigh))
	281	kfree_skb(skb);
	282	} else {
	283	skb_queue_tail(&neigh->queue, skb);
	284
	285	if (!rose_t0timer_running(neigh)) {
	286	rose_transmit_restart_request(neigh);
	287	neigh->dce_mode = 0;
	288	rose_start_t0timer(neigh);
	289	}
	290	}
	291	}