[linux-2.6-block.git] / net / ax25 / ax25_iface.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 * 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/module.h>
#include <linux/spinlock.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/uaccess.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>

static struct ax25_protocol *protocol_list;
static DEFINE_RWLOCK(protocol_list_lock);

static HLIST_HEAD(ax25_linkfail_list);
static DEFINE_SPINLOCK(linkfail_lock);

static struct listen_struct {
	struct listen_struct *next;
	ax25_address  callsign;
	struct net_device *dev;
} *listen_list = NULL;
static DEFINE_SPINLOCK(listen_lock);

/*
 * Do not register the internal protocols AX25_P_TEXT, AX25_P_SEGMENT,
 * AX25_P_IP or AX25_P_ARP ...
 */
void ax25_register_pid(struct ax25_protocol *ap)
{
	write_lock_bh(&protocol_list_lock);
	ap->next = protocol_list;
	protocol_list = ap;
	write_unlock_bh(&protocol_list_lock);
}

EXPORT_SYMBOL_GPL(ax25_register_pid);

void ax25_protocol_release(unsigned int pid)
{
	struct ax25_protocol *protocol;

	write_lock_bh(&protocol_list_lock);
	protocol = protocol_list;
	if (protocol == NULL)
		goto out;

	if (protocol->pid == pid) {
		protocol_list = protocol->next;
		goto out;
	}

	while (protocol != NULL && protocol->next != NULL) {
		if (protocol->next->pid == pid) {
			protocol->next = protocol->next->next;
			goto out;
		}

		protocol = protocol->next;
	}
out:
	write_unlock_bh(&protocol_list_lock);
}

EXPORT_SYMBOL(ax25_protocol_release);

void ax25_linkfail_register(struct ax25_linkfail *lf)
{
	spin_lock_bh(&linkfail_lock);
	hlist_add_head(&lf->lf_node, &ax25_linkfail_list);
	spin_unlock_bh(&linkfail_lock);
}

EXPORT_SYMBOL(ax25_linkfail_register);

void ax25_linkfail_release(struct ax25_linkfail *lf)
{
	spin_lock_bh(&linkfail_lock);
	hlist_del_init(&lf->lf_node);
	spin_unlock_bh(&linkfail_lock);
}

EXPORT_SYMBOL(ax25_linkfail_release);

int ax25_listen_register(ax25_address *callsign, struct net_device *dev)
{
	struct listen_struct *listen;

	if (ax25_listen_mine(callsign, dev))
		return 0;

	if ((listen = kmalloc(sizeof(*listen), GFP_ATOMIC)) == NULL)
		return -ENOMEM;

	listen->callsign = *callsign;
	listen->dev      = dev;

	spin_lock_bh(&listen_lock);
	listen->next = listen_list;
	listen_list  = listen;
	spin_unlock_bh(&listen_lock);

	return 0;
}

EXPORT_SYMBOL(ax25_listen_register);

void ax25_listen_release(ax25_address *callsign, struct net_device *dev)
{
	struct listen_struct *s, *listen;

	spin_lock_bh(&listen_lock);
	listen = listen_list;
	if (listen == NULL) {
		spin_unlock_bh(&listen_lock);
		return;
	}

	if (ax25cmp(&listen->callsign, callsign) == 0 && listen->dev == dev) {
		listen_list = listen->next;
		spin_unlock_bh(&listen_lock);
		kfree(listen);
		return;
	}

	while (listen != NULL && listen->next != NULL) {
		if (ax25cmp(&listen->next->callsign, callsign) == 0 && listen->next->dev == dev) {
			s = listen->next;
			listen->next = listen->next->next;
			spin_unlock_bh(&listen_lock);
			kfree(s);
			return;
		}

		listen = listen->next;
	}
	spin_unlock_bh(&listen_lock);
}

EXPORT_SYMBOL(ax25_listen_release);

int (*ax25_protocol_function(unsigned int pid))(struct sk_buff *, ax25_cb *)
{
	int (*res)(struct sk_buff *, ax25_cb *) = NULL;
	struct ax25_protocol *protocol;

	read_lock(&protocol_list_lock);
	for (protocol = protocol_list; protocol != NULL; protocol = protocol->next)
		if (protocol->pid == pid) {
			res = protocol->func;
			break;
		}
	read_unlock(&protocol_list_lock);

	return res;
}

int ax25_listen_mine(ax25_address *callsign, struct net_device *dev)
{
	struct listen_struct *listen;

	spin_lock_bh(&listen_lock);
	for (listen = listen_list; listen != NULL; listen = listen->next)
		if (ax25cmp(&listen->callsign, callsign) == 0 &&
		    (listen->dev == dev || listen->dev == NULL)) {
			spin_unlock_bh(&listen_lock);
			return 1;
	}
	spin_unlock_bh(&listen_lock);

	return 0;
}

void ax25_link_failed(ax25_cb *ax25, int reason)
{
	struct ax25_linkfail *lf;

	spin_lock_bh(&linkfail_lock);
	hlist_for_each_entry(lf, &ax25_linkfail_list, lf_node)
		lf->func(ax25, reason);
	spin_unlock_bh(&linkfail_lock);
}

int ax25_protocol_is_registered(unsigned int pid)
{
	struct ax25_protocol *protocol;
	int res = 0;

	read_lock_bh(&protocol_list_lock);
	for (protocol = protocol_list; protocol != NULL; protocol = protocol->next)
		if (protocol->pid == pid) {
			res = 1;
			break;
		}
	read_unlock_bh(&protocol_list_lock);

	return res;
}
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4	2	/*
1da177e4 LT	3	*
	4	* Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
	5	*/
1da177e4 LT	6	#include <linux/errno.h>
	7	#include <linux/types.h>
	8	#include <linux/socket.h>
	9	#include <linux/in.h>
	10	#include <linux/kernel.h>
70868eac	11	#include <linux/module.h>
1da177e4 LT	12	#include <linux/spinlock.h>
	13	#include <linux/timer.h>
	14	#include <linux/string.h>
	15	#include <linux/sockios.h>
	16	#include <linux/net.h>
5a0e3ad6	17	#include <linux/slab.h>
1da177e4 LT	18	#include <net/ax25.h>
	19	#include <linux/inet.h>
	20	#include <linux/netdevice.h>
	21	#include <linux/skbuff.h>
	22	#include <net/sock.h>
7c0f6ba6	23	#include <linux/uaccess.h>
1da177e4 LT	24	#include <linux/fcntl.h>
	25	#include <linux/mm.h>
	26	#include <linux/interrupt.h>
	27
8d5cf596	28	static struct ax25_protocol *protocol_list;
1da177e4 LT	29	static DEFINE_RWLOCK(protocol_list_lock);
1da177e4 LT	30
a4282717	31	static HLIST_HEAD(ax25_linkfail_list);
1da177e4 LT	32	static DEFINE_SPINLOCK(linkfail_lock);
	33
	34	static struct listen_struct {
	35	struct listen_struct *next;
	36	ax25_address callsign;
	37	struct net_device *dev;
	38	} *listen_list = NULL;
	39	static DEFINE_SPINLOCK(listen_lock);
	40
8d5cf596 RB	41	/*
	42	* Do not register the internal protocols AX25_P_TEXT, AX25_P_SEGMENT,
	43	* AX25_P_IP or AX25_P_ARP ...
	44	*/
	45	void ax25_register_pid(struct ax25_protocol *ap)
1da177e4	46	{
95ff9f4d	47	write_lock_bh(&protocol_list_lock);
8d5cf596 RB	48	ap->next = protocol_list;
8d5cf596 RB	49	protocol_list = ap;
95ff9f4d	50	write_unlock_bh(&protocol_list_lock);
1da177e4 LT	51	}
1da177e4 LT	52
8d5cf596	53	EXPORT_SYMBOL_GPL(ax25_register_pid);
70868eac	54
1da177e4 LT	55	void ax25_protocol_release(unsigned int pid)
1da177e4 LT	56	{
d8f969e6	57	struct ax25_protocol *protocol;
1da177e4	58
95ff9f4d	59	write_lock_bh(&protocol_list_lock);
1da177e4	60	protocol = protocol_list;
910d30b7 IJ	61	if (protocol == NULL)
910d30b7 IJ	62	goto out;
1da177e4 LT	63
	64	if (protocol->pid == pid) {
	65	protocol_list = protocol->next;
910d30b7	66	goto out;
1da177e4 LT	67	}
	68
	69	while (protocol != NULL && protocol->next != NULL) {
	70	if (protocol->next->pid == pid) {
1da177e4	71	protocol->next = protocol->next->next;
910d30b7	72	goto out;
1da177e4 LT	73	}
	74
	75	protocol = protocol->next;
	76	}
910d30b7	77	out:
95ff9f4d	78	write_unlock_bh(&protocol_list_lock);
1da177e4 LT	79	}
1da177e4 LT	80
70868eac RB	81	EXPORT_SYMBOL(ax25_protocol_release);
70868eac RB	82
a4282717	83	void ax25_linkfail_register(struct ax25_linkfail *lf)
1da177e4	84	{
1da177e4	85	spin_lock_bh(&linkfail_lock);
a4282717	86	hlist_add_head(&lf->lf_node, &ax25_linkfail_list);
1da177e4	87	spin_unlock_bh(&linkfail_lock);
1da177e4 LT	88	}
1da177e4 LT	89
70868eac RB	90	EXPORT_SYMBOL(ax25_linkfail_register);
70868eac RB	91
a4282717	92	void ax25_linkfail_release(struct ax25_linkfail *lf)
1da177e4	93	{
1da177e4	94	spin_lock_bh(&linkfail_lock);
a4282717	95	hlist_del_init(&lf->lf_node);
1da177e4 LT	96	spin_unlock_bh(&linkfail_lock);
	97	}
	98
70868eac RB	99	EXPORT_SYMBOL(ax25_linkfail_release);
70868eac RB	100
1da177e4 LT	101	int ax25_listen_register(ax25_address callsign, struct net_device dev)
	102	{
	103	struct listen_struct *listen;
	104
	105	if (ax25_listen_mine(callsign, dev))
	106	return 0;
	107
	108	if ((listen = kmalloc(sizeof(*listen), GFP_ATOMIC)) == NULL)
81dcd169	109	return -ENOMEM;
1da177e4 LT	110
	111	listen->callsign = *callsign;
	112	listen->dev = dev;
	113
	114	spin_lock_bh(&listen_lock);
	115	listen->next = listen_list;
	116	listen_list = listen;
	117	spin_unlock_bh(&listen_lock);
	118
81dcd169	119	return 0;
1da177e4 LT	120	}
1da177e4 LT	121
70868eac RB	122	EXPORT_SYMBOL(ax25_listen_register);
70868eac RB	123
1da177e4 LT	124	void ax25_listen_release(ax25_address callsign, struct net_device dev)
	125	{
	126	struct listen_struct s, listen;
	127
	128	spin_lock_bh(&listen_lock);
	129	listen = listen_list;
	130	if (listen == NULL) {
	131	spin_unlock_bh(&listen_lock);
	132	return;
	133	}
	134
	135	if (ax25cmp(&listen->callsign, callsign) == 0 && listen->dev == dev) {
	136	listen_list = listen->next;
	137	spin_unlock_bh(&listen_lock);
	138	kfree(listen);
	139	return;
	140	}
	141
	142	while (listen != NULL && listen->next != NULL) {
	143	if (ax25cmp(&listen->next->callsign, callsign) == 0 && listen->next->dev == dev) {
	144	s = listen->next;
	145	listen->next = listen->next->next;
	146	spin_unlock_bh(&listen_lock);
	147	kfree(s);
	148	return;
	149	}
	150
	151	listen = listen->next;
	152	}
	153	spin_unlock_bh(&listen_lock);
	154	}
	155
70868eac RB	156	EXPORT_SYMBOL(ax25_listen_release);
70868eac RB	157
1da177e4 LT	158	int (ax25_protocol_function(unsigned int pid))(struct sk_buff , ax25_cb *)
	159	{
	160	int (res)(struct sk_buff , ax25_cb *) = NULL;
8d5cf596	161	struct ax25_protocol *protocol;
1da177e4 LT	162
	163	read_lock(&protocol_list_lock);
	164	for (protocol = protocol_list; protocol != NULL; protocol = protocol->next)
	165	if (protocol->pid == pid) {
	166	res = protocol->func;
	167	break;
	168	}
	169	read_unlock(&protocol_list_lock);
	170
	171	return res;
	172	}
	173
	174	int ax25_listen_mine(ax25_address callsign, struct net_device dev)
	175	{
	176	struct listen_struct *listen;
	177
	178	spin_lock_bh(&listen_lock);
	179	for (listen = listen_list; listen != NULL; listen = listen->next)
81dcd169 RB	180	if (ax25cmp(&listen->callsign, callsign) == 0 &&
81dcd169 RB	181	(listen->dev == dev \|\| listen->dev == NULL)) {
1da177e4 LT	182	spin_unlock_bh(&listen_lock);
	183	return 1;
	184	}
	185	spin_unlock_bh(&listen_lock);
	186
	187	return 0;
	188	}
	189
	190	void ax25_link_failed(ax25_cb *ax25, int reason)
	191	{
a4282717	192	struct ax25_linkfail *lf;
1da177e4 LT	193
1da177e4 LT	194	spin_lock_bh(&linkfail_lock);
b67bfe0d	195	hlist_for_each_entry(lf, &ax25_linkfail_list, lf_node)
a4282717	196	lf->func(ax25, reason);
1da177e4 LT	197	spin_unlock_bh(&linkfail_lock);
	198	}
	199
	200	int ax25_protocol_is_registered(unsigned int pid)
	201	{
8d5cf596	202	struct ax25_protocol *protocol;
1da177e4 LT	203	int res = 0;
1da177e4 LT	204
95ff9f4d	205	read_lock_bh(&protocol_list_lock);
1da177e4 LT	206	for (protocol = protocol_list; protocol != NULL; protocol = protocol->next)
	207	if (protocol->pid == pid) {
	208	res = 1;
	209	break;
	210	}
95ff9f4d	211	read_unlock_bh(&protocol_list_lock);
1da177e4 LT	212
	213	return res;
	214	}