[linux.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 ([email protected])
 */

#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/sched.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/spinlock.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 <net/ip.h>
#include <net/arp.h>

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

HLIST_HEAD(ax25_uid_list);
static DEFINE_RWLOCK(ax25_uid_lock);

int ax25_uid_policy = 0;

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)
{
	struct ax25_uid_assoc *pt;
	struct hlist_node *node;
	int i = 0;

	read_lock(&ax25_uid_lock);
	ax25_uid_for_each(pt, node, &ax25_uid_list) {
		if (i == *pos)
			return pt;
		++i;
	}
	return NULL;
}

static void *ax25_uid_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	++*pos;

	return hlist_entry(((ax25_uid_assoc *)v)->uid_node.next,
			   ax25_uid_assoc, uid_node);
}

static void ax25_uid_seq_stop(struct seq_file *seq, void *v)
{
	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 = v;

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

static 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);
	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
		hlist_del_init(&ax25_uid->uid_node);
		ax25_uid_put(ax25_uid);
	}
	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 ([email protected])
	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>
	16	#include <linux/sched.h>
	17	#include <linux/timer.h>
	18	#include <linux/string.h>
	19	#include <linux/sockios.h>
	20	#include <linux/net.h>
	21	#include <linux/spinlock.h>
	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>
	40	#include <net/ip.h>
	41	#include <net/arp.h>
	42
	43	/*
	44	* Callsign/UID mapper. This is in kernel space for security on multi-amateur machines.
	45	*/
	46
01d7dd0e	47	HLIST_HEAD(ax25_uid_list);
1da177e4 LT	48	static DEFINE_RWLOCK(ax25_uid_lock);
	49
	50	int ax25_uid_policy = 0;
	51
70868eac RB	52	EXPORT_SYMBOL(ax25_uid_policy);
70868eac RB	53
01d7dd0e	54	ax25_uid_assoc *ax25_findbyuid(uid_t uid)
1da177e4	55	{
01d7dd0e RB	56	ax25_uid_assoc ax25_uid, res = NULL;
01d7dd0e RB	57	struct hlist_node *node;
1da177e4 LT	58
1da177e4 LT	59	read_lock(&ax25_uid_lock);
01d7dd0e	60	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
1da177e4	61	if (ax25_uid->uid == uid) {
01d7dd0e RB	62	ax25_uid_hold(ax25_uid);
01d7dd0e RB	63	res = ax25_uid;
1da177e4 LT	64	break;
	65	}
	66	}
	67	read_unlock(&ax25_uid_lock);
	68
01d7dd0e	69	return res;
1da177e4 LT	70	}
1da177e4 LT	71
70868eac RB	72	EXPORT_SYMBOL(ax25_findbyuid);
70868eac RB	73
1da177e4 LT	74	int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
1da177e4 LT	75	{
01d7dd0e RB	76	ax25_uid_assoc *ax25_uid;
	77	struct hlist_node *node;
	78	ax25_uid_assoc *user;
1da177e4 LT	79	unsigned long res;
	80
	81	switch (cmd) {
	82	case SIOCAX25GETUID:
	83	res = -ENOENT;
	84	read_lock(&ax25_uid_lock);
01d7dd0e	85	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
1da177e4 LT	86	if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0) {
	87	res = ax25_uid->uid;
	88	break;
	89	}
	90	}
	91	read_unlock(&ax25_uid_lock);
	92
	93	return res;
	94
	95	case SIOCAX25ADDUID:
	96	if (!capable(CAP_NET_ADMIN))
	97	return -EPERM;
01d7dd0e RB	98	user = ax25_findbyuid(sax->sax25_uid);
	99	if (user) {
	100	ax25_uid_put(user);
1da177e4	101	return -EEXIST;
01d7dd0e	102	}
1da177e4 LT	103	if (sax->sax25_uid == 0)
	104	return -EINVAL;
	105	if ((ax25_uid = kmalloc(sizeof(*ax25_uid), GFP_KERNEL)) == NULL)
	106	return -ENOMEM;
	107
01d7dd0e	108	atomic_set(&ax25_uid->refcount, 1);
1da177e4 LT	109	ax25_uid->uid = sax->sax25_uid;
	110	ax25_uid->call = sax->sax25_call;
	111
	112	write_lock(&ax25_uid_lock);
01d7dd0e	113	hlist_add_head(&ax25_uid->uid_node, &ax25_uid_list);
1da177e4 LT	114	write_unlock(&ax25_uid_lock);
	115
	116	return 0;
	117
	118	case SIOCAX25DELUID:
	119	if (!capable(CAP_NET_ADMIN))
	120	return -EPERM;
	121
01d7dd0e	122	ax25_uid = NULL;
1da177e4	123	write_lock(&ax25_uid_lock);
01d7dd0e RB	124	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
01d7dd0e RB	125	if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0)
1da177e4	126	break;
1da177e4 LT	127	}
	128	if (ax25_uid == NULL) {
	129	write_unlock(&ax25_uid_lock);
	130	return -ENOENT;
	131	}
01d7dd0e RB	132	hlist_del_init(&ax25_uid->uid_node);
01d7dd0e RB	133	ax25_uid_put(ax25_uid);
1da177e4 LT	134	write_unlock(&ax25_uid_lock);
1da177e4 LT	135
01d7dd0e	136	return 0;
1da177e4 LT	137
	138	default:
	139	return -EINVAL;
	140	}
	141
	142	return -EINVAL; /NOTREACHED /
	143	}
	144
	145	#ifdef CONFIG_PROC_FS
	146
	147	static void ax25_uid_seq_start(struct seq_file seq, loff_t *pos)
	148	{
	149	struct ax25_uid_assoc *pt;
01d7dd0e RB	150	struct hlist_node *node;
01d7dd0e RB	151	int i = 0;
1da177e4 LT	152
1da177e4 LT	153	read_lock(&ax25_uid_lock);
01d7dd0e	154	ax25_uid_for_each(pt, node, &ax25_uid_list) {
1da177e4 LT	155	if (i == *pos)
	156	return pt;
	157	++i;
	158	}
	159	return NULL;
	160	}
	161
	162	static void ax25_uid_seq_next(struct seq_file seq, void v, loff_t pos)
	163	{
	164	++*pos;
01d7dd0e RB	165
01d7dd0e RB	166	return hlist_entry(((ax25_uid_assoc *)v)->uid_node.next,
528930b9	167	ax25_uid_assoc, uid_node);
1da177e4 LT	168	}
	169
	170	static void ax25_uid_seq_stop(struct seq_file seq, void v)
	171	{
	172	read_unlock(&ax25_uid_lock);
	173	}
	174
	175	static int ax25_uid_seq_show(struct seq_file seq, void v)
	176	{
f75268cd RB	177	char buf[11];
f75268cd RB	178
1da177e4 LT	179	if (v == SEQ_START_TOKEN)
	180	seq_printf(seq, "Policy: %d\n", ax25_uid_policy);
	181	else {
	182	struct ax25_uid_assoc *pt = v;
1da177e4	183
f75268cd	184	seq_printf(seq, "%6d %s\n", pt->uid, ax2asc(buf, &pt->call));
1da177e4 LT	185	}
	186	return 0;
	187	}
	188
	189	static struct seq_operations ax25_uid_seqops = {
	190	.start = ax25_uid_seq_start,
	191	.next = ax25_uid_seq_next,
	192	.stop = ax25_uid_seq_stop,
	193	.show = ax25_uid_seq_show,
	194	};
	195
	196	static int ax25_uid_info_open(struct inode inode, struct file file)
	197	{
	198	return seq_open(file, &ax25_uid_seqops);
	199	}
	200
9a32144e	201	const struct file_operations ax25_uid_fops = {
1da177e4 LT	202	.owner = THIS_MODULE,
	203	.open = ax25_uid_info_open,
	204	.read = seq_read,
	205	.llseek = seq_lseek,
	206	.release = seq_release,
	207	};
	208
	209	#endif
	210
	211	/*
	212	* Free all memory associated with UID/Callsign structures.
	213	*/
	214	void __exit ax25_uid_free(void)
	215	{
01d7dd0e RB	216	ax25_uid_assoc *ax25_uid;
01d7dd0e RB	217	struct hlist_node *node;
1da177e4 LT	218
1da177e4 LT	219	write_lock(&ax25_uid_lock);
01d7dd0e RB	220	ax25_uid_for_each(ax25_uid, node, &ax25_uid_list) {
	221	hlist_del_init(&ax25_uid->uid_node);
	222	ax25_uid_put(ax25_uid);
1da177e4	223	}
1da177e4 LT	224	write_unlock(&ax25_uid_lock);
1da177e4 LT	225	}