[linux-2.6-block.git] / net / ax25 / ax25_uid.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/capability.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <net/ax25.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/notifier.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/stat.h>
#include <linux/netfilter.h>
#include <linux/sysctl.h>
#include <linux/export.h>
#include <net/ip.h>
#include <net/arp.h>

/*
 *	Callsign/UID mapper. This is in kernel space for security on multi-amateur machines.
 */

static HLIST_HEAD(ax25_uid_list);
static DEFINE_RWLOCK(ax25_uid_lock);

int ax25_uid_policy;

EXPORT_SYMBOL(ax25_uid_policy);

ax25_uid_assoc *ax25_findbyuid(uid_t uid)
{
	ax25_uid_assoc *ax25_uid, *res = NULL;
	struct hlist_node *node;

	read_lock(&ax25_uid_lock);
	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
		if (ax25_uid->uid == uid) {
			ax25_uid_hold(ax25_uid);
			res = ax25_uid;
			break;
		}
	}
	read_unlock(&ax25_uid_lock);

	return res;
}

EXPORT_SYMBOL(ax25_findbyuid);

int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
{
	ax25_uid_assoc *ax25_uid;
	struct hlist_node *node;
	ax25_uid_assoc *user;
	unsigned long res;

	switch (cmd) {
	case SIOCAX25GETUID:
		res = -ENOENT;
		read_lock(&ax25_uid_lock);
		ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
			if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0) {
				res = ax25_uid->uid;
				break;
			}
		}
		read_unlock(&ax25_uid_lock);

		return res;

	case SIOCAX25ADDUID:
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		user = ax25_findbyuid(sax->sax25_uid);
		if (user) {
			ax25_uid_put(user);
			return -EEXIST;
		}
		if (sax->sax25_uid == 0)
			return -EINVAL;
		if ((ax25_uid = kmalloc(sizeof(*ax25_uid), GFP_KERNEL)) == NULL)
			return -ENOMEM;

		atomic_set(&ax25_uid->refcount, 1);
		ax25_uid->uid  = sax->sax25_uid;
		ax25_uid->call = sax->sax25_call;

		write_lock(&ax25_uid_lock);
		hlist_add_head(&ax25_uid->uid_node, &ax25_uid_list);
		write_unlock(&ax25_uid_lock);

		return 0;

	case SIOCAX25DELUID:
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;

		ax25_uid = NULL;
		write_lock(&ax25_uid_lock);
		ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
			if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0)
				break;
		}
		if (ax25_uid == NULL) {
			write_unlock(&ax25_uid_lock);
			return -ENOENT;
		}
		hlist_del_init(&ax25_uid->uid_node);
		ax25_uid_put(ax25_uid);
		write_unlock(&ax25_uid_lock);

		return 0;

	default:
		return -EINVAL;
	}

	return -EINVAL;	/*NOTREACHED */
}

#ifdef CONFIG_PROC_FS

static void *ax25_uid_seq_start(struct seq_file *seq, loff_t *pos)
	__acquires(ax25_uid_lock)
{
	read_lock(&ax25_uid_lock);
	return seq_hlist_start_head(&ax25_uid_list, *pos);
}

static void *ax25_uid_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	return seq_hlist_next(v, &ax25_uid_list, pos);
}

static void ax25_uid_seq_stop(struct seq_file *seq, void *v)
	__releases(ax25_uid_lock)
{
	read_unlock(&ax25_uid_lock);
}

static int ax25_uid_seq_show(struct seq_file *seq, void *v)
{
	char buf[11];

	if (v == SEQ_START_TOKEN)
		seq_printf(seq, "Policy: %d\n", ax25_uid_policy);
	else {
		struct ax25_uid_assoc *pt;

		pt = hlist_entry(v, struct ax25_uid_assoc, uid_node);
		seq_printf(seq, "%6d %s\n", pt->uid, ax2asc(buf, &pt->call));
	}
	return 0;
}

static const struct seq_operations ax25_uid_seqops = {
	.start = ax25_uid_seq_start,
	.next = ax25_uid_seq_next,
	.stop = ax25_uid_seq_stop,
	.show = ax25_uid_seq_show,
};

static int ax25_uid_info_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &ax25_uid_seqops);
}

const struct file_operations ax25_uid_fops = {
	.owner = THIS_MODULE,
	.open = ax25_uid_info_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = seq_release,
};

#endif

/*
 *	Free all memory associated with UID/Callsign structures.
 */
void __exit ax25_uid_free(void)
{
	ax25_uid_assoc *ax25_uid;
	struct hlist_node *node;

	write_lock(&ax25_uid_lock);
again:
	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
		hlist_del_init(&ax25_uid->uid_node);
		ax25_uid_put(ax25_uid);
		goto again;
	}
	write_unlock(&ax25_uid_lock);
}
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	*/
4fc268d2 RD	9
4fc268d2 RD	10	#include <linux/capability.h>
1da177e4 LT	11	#include <linux/errno.h>
	12	#include <linux/types.h>
	13	#include <linux/socket.h>
	14	#include <linux/in.h>
	15	#include <linux/kernel.h>
1da177e4 LT	16	#include <linux/timer.h>
	17	#include <linux/string.h>
	18	#include <linux/sockios.h>
	19	#include <linux/net.h>
	20	#include <linux/spinlock.h>
5a0e3ad6	21	#include <linux/slab.h>
1da177e4 LT	22	#include <net/ax25.h>
	23	#include <linux/inet.h>
	24	#include <linux/netdevice.h>
	25	#include <linux/if_arp.h>
	26	#include <linux/skbuff.h>
	27	#include <net/sock.h>
	28	#include <asm/uaccess.h>
	29	#include <asm/system.h>
	30	#include <linux/fcntl.h>
	31	#include <linux/mm.h>
	32	#include <linux/interrupt.h>
01d7dd0e	33	#include <linux/list.h>
1da177e4 LT	34	#include <linux/notifier.h>
	35	#include <linux/proc_fs.h>
	36	#include <linux/seq_file.h>
	37	#include <linux/stat.h>
	38	#include <linux/netfilter.h>
	39	#include <linux/sysctl.h>
bc3b2d7f	40	#include <linux/export.h>
1da177e4 LT	41	#include <net/ip.h>
	42	#include <net/arp.h>
	43
	44	/*
	45	* Callsign/UID mapper. This is in kernel space for security on multi-amateur machines.
	46	*/
	47
f16f3026	48	static HLIST_HEAD(ax25_uid_list);
1da177e4 LT	49	static DEFINE_RWLOCK(ax25_uid_lock);
1da177e4 LT	50
f16f3026	51	int ax25_uid_policy;
1da177e4	52
70868eac RB	53	EXPORT_SYMBOL(ax25_uid_policy);
70868eac RB	54
01d7dd0e	55	ax25_uid_assoc *ax25_findbyuid(uid_t uid)
1da177e4	56	{
01d7dd0e RB	57	ax25_uid_assoc ax25_uid, res = NULL;
01d7dd0e RB	58	struct hlist_node *node;
1da177e4 LT	59
1da177e4 LT	60	read_lock(&ax25_uid_lock);
01d7dd0e	61	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
1da177e4	62	if (ax25_uid->uid == uid) {
01d7dd0e RB	63	ax25_uid_hold(ax25_uid);
01d7dd0e RB	64	res = ax25_uid;
1da177e4 LT	65	break;
	66	}
	67	}
	68	read_unlock(&ax25_uid_lock);
	69
01d7dd0e	70	return res;
1da177e4 LT	71	}
1da177e4 LT	72
70868eac RB	73	EXPORT_SYMBOL(ax25_findbyuid);
70868eac RB	74
1da177e4 LT	75	int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
1da177e4 LT	76	{
01d7dd0e RB	77	ax25_uid_assoc *ax25_uid;
	78	struct hlist_node *node;
	79	ax25_uid_assoc *user;
1da177e4 LT	80	unsigned long res;
	81
	82	switch (cmd) {
	83	case SIOCAX25GETUID:
	84	res = -ENOENT;
	85	read_lock(&ax25_uid_lock);
01d7dd0e	86	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
1da177e4 LT	87	if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0) {
	88	res = ax25_uid->uid;
	89	break;
	90	}
	91	}
	92	read_unlock(&ax25_uid_lock);
	93
	94	return res;
	95
	96	case SIOCAX25ADDUID:
	97	if (!capable(CAP_NET_ADMIN))
	98	return -EPERM;
01d7dd0e RB	99	user = ax25_findbyuid(sax->sax25_uid);
	100	if (user) {
	101	ax25_uid_put(user);
1da177e4	102	return -EEXIST;
01d7dd0e	103	}
1da177e4 LT	104	if (sax->sax25_uid == 0)
	105	return -EINVAL;
	106	if ((ax25_uid = kmalloc(sizeof(*ax25_uid), GFP_KERNEL)) == NULL)
	107	return -ENOMEM;
	108
01d7dd0e	109	atomic_set(&ax25_uid->refcount, 1);
1da177e4 LT	110	ax25_uid->uid = sax->sax25_uid;
	111	ax25_uid->call = sax->sax25_call;
	112
	113	write_lock(&ax25_uid_lock);
01d7dd0e	114	hlist_add_head(&ax25_uid->uid_node, &ax25_uid_list);
1da177e4 LT	115	write_unlock(&ax25_uid_lock);
	116
	117	return 0;
	118
	119	case SIOCAX25DELUID:
	120	if (!capable(CAP_NET_ADMIN))
	121	return -EPERM;
	122
01d7dd0e	123	ax25_uid = NULL;
1da177e4	124	write_lock(&ax25_uid_lock);
01d7dd0e RB	125	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
01d7dd0e RB	126	if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0)
1da177e4	127	break;
1da177e4 LT	128	}
	129	if (ax25_uid == NULL) {
	130	write_unlock(&ax25_uid_lock);
	131	return -ENOENT;
	132	}
01d7dd0e RB	133	hlist_del_init(&ax25_uid->uid_node);
01d7dd0e RB	134	ax25_uid_put(ax25_uid);
1da177e4 LT	135	write_unlock(&ax25_uid_lock);
1da177e4 LT	136
01d7dd0e	137	return 0;
1da177e4 LT	138
	139	default:
	140	return -EINVAL;
	141	}
	142
	143	return -EINVAL; /NOTREACHED /
	144	}
	145
	146	#ifdef CONFIG_PROC_FS
	147
	148	static void ax25_uid_seq_start(struct seq_file seq, loff_t *pos)
f16f3026	149	__acquires(ax25_uid_lock)
1da177e4	150	{
1da177e4	151	read_lock(&ax25_uid_lock);
b512f3d8	152	return seq_hlist_start_head(&ax25_uid_list, *pos);
1da177e4 LT	153	}
	154
	155	static void ax25_uid_seq_next(struct seq_file seq, void v, loff_t pos)
	156	{
b512f3d8	157	return seq_hlist_next(v, &ax25_uid_list, pos);
1da177e4 LT	158	}
	159
	160	static void ax25_uid_seq_stop(struct seq_file seq, void v)
f16f3026	161	__releases(ax25_uid_lock)
1da177e4 LT	162	{
	163	read_unlock(&ax25_uid_lock);
	164	}
	165
	166	static int ax25_uid_seq_show(struct seq_file seq, void v)
	167	{
f75268cd RB	168	char buf[11];
f75268cd RB	169
1da177e4 LT	170	if (v == SEQ_START_TOKEN)
	171	seq_printf(seq, "Policy: %d\n", ax25_uid_policy);
	172	else {
b512f3d8	173	struct ax25_uid_assoc *pt;
1da177e4	174
b512f3d8	175	pt = hlist_entry(v, struct ax25_uid_assoc, uid_node);
f75268cd	176	seq_printf(seq, "%6d %s\n", pt->uid, ax2asc(buf, &pt->call));
1da177e4 LT	177	}
	178	return 0;
	179	}
	180
56b3d975	181	static const struct seq_operations ax25_uid_seqops = {
1da177e4 LT	182	.start = ax25_uid_seq_start,
	183	.next = ax25_uid_seq_next,
	184	.stop = ax25_uid_seq_stop,
	185	.show = ax25_uid_seq_show,
	186	};
	187
	188	static int ax25_uid_info_open(struct inode inode, struct file file)
	189	{
	190	return seq_open(file, &ax25_uid_seqops);
	191	}
	192
9a32144e	193	const struct file_operations ax25_uid_fops = {
1da177e4 LT	194	.owner = THIS_MODULE,
	195	.open = ax25_uid_info_open,
	196	.read = seq_read,
	197	.llseek = seq_lseek,
	198	.release = seq_release,
	199	};
	200
	201	#endif
	202
	203	/*
	204	* Free all memory associated with UID/Callsign structures.
	205	*/
	206	void __exit ax25_uid_free(void)
	207	{
01d7dd0e RB	208	ax25_uid_assoc *ax25_uid;
01d7dd0e RB	209	struct hlist_node *node;
1da177e4 LT	210
1da177e4 LT	211	write_lock(&ax25_uid_lock);
ae1b6a31	212	again:
01d7dd0e RB	213	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
	214	hlist_del_init(&ax25_uid->uid_node);
	215	ax25_uid_put(ax25_uid);
ae1b6a31	216	goto again;
1da177e4	217	}
1da177e4 LT	218	write_unlock(&ax25_uid_lock);
1da177e4 LT	219	}