1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * File: sysctl.c
 4 *
 5 * Phonet /proc/sys/net/phonet interface implementation
 6 *
 7 * Copyright (C) 2008 Nokia Corporation.
 8 *
 9 * Author: Rémi Denis-Courmont
10 */
11
12#include <linux/seqlock.h>
13#include <linux/sysctl.h>
14#include <linux/errno.h>
15#include <linux/init.h>
16
17#include <net/sock.h>
18#include <linux/phonet.h>
19#include <net/phonet/phonet.h>
20
21#define DYNAMIC_PORT_MIN	0x40
22#define DYNAMIC_PORT_MAX	0x7f
23
24static DEFINE_SEQLOCK(local_port_range_lock);
25static int local_port_range_min[2] = {0, 0};
26static int local_port_range_max[2] = {1023, 1023};
27static int local_port_range[2] = {DYNAMIC_PORT_MIN, DYNAMIC_PORT_MAX};
28static struct ctl_table_header *phonet_table_hrd;
29
30static void set_local_port_range(int range[2])
31{
32	write_seqlock(&local_port_range_lock);
33	local_port_range[0] = range[0];
34	local_port_range[1] = range[1];
35	write_sequnlock(&local_port_range_lock);
36}
37
38void phonet_get_local_port_range(int *min, int *max)
39{
40	unsigned int seq;
41
42	do {
43		seq = read_seqbegin(&local_port_range_lock);
44		if (min)
45			*min = local_port_range[0];
46		if (max)
47			*max = local_port_range[1];
48	} while (read_seqretry(&local_port_range_lock, seq));
49}
50
51static int proc_local_port_range(struct ctl_table *table, int write,
52				 void *buffer, size_t *lenp, loff_t *ppos)
53{
54	int ret;
55	int range[2] = {local_port_range[0], local_port_range[1]};
56	struct ctl_table tmp = {
57		.data = &range,
58		.maxlen = sizeof(range),
59		.mode = table->mode,
60		.extra1 = &local_port_range_min,
61		.extra2 = &local_port_range_max,
62	};
63
64	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
65
66	if (write && ret == 0) {
67		if (range[1] < range[0])
68			ret = -EINVAL;
69		else
70			set_local_port_range(range);
71	}
72
73	return ret;
74}
75
76static struct ctl_table phonet_table[] = {
77	{
78		.procname	= "local_port_range",
79		.data		= &local_port_range,
80		.maxlen		= sizeof(local_port_range),
81		.mode		= 0644,
82		.proc_handler	= proc_local_port_range,
83	},
84	{ }
85};
86
87int __init phonet_sysctl_init(void)
88{
89	phonet_table_hrd = register_net_sysctl(&init_net, "net/phonet", phonet_table);
90	return phonet_table_hrd == NULL ? -ENOMEM : 0;
91}
92
93void phonet_sysctl_exit(void)
94{
95	unregister_net_sysctl_table(phonet_table_hrd);
96}

  1/*
  2 * File: sysctl.c
  3 *
  4 * Phonet /proc/sys/net/phonet interface implementation
  5 *
  6 * Copyright (C) 2008 Nokia Corporation.
  7 *
  8 * Author: Rémi Denis-Courmont
  9 *
 10 * This program is free software; you can redistribute it and/or
 11 * modify it under the terms of the GNU General Public License
 12 * version 2 as published by the Free Software Foundation.
 13 *
 14 * This program is distributed in the hope that it will be useful, but
 15 * WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 17 * General Public License for more details.
 18 *
 19 * You should have received a copy of the GNU General Public License
 20 * along with this program; if not, write to the Free Software
 21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 22 * 02110-1301 USA
 23 */
 24
 25#include <linux/seqlock.h>
 26#include <linux/sysctl.h>
 27#include <linux/errno.h>
 28#include <linux/init.h>
 29
 30#include <net/sock.h>
 31#include <linux/phonet.h>
 32#include <net/phonet/phonet.h>
 33
 34#define DYNAMIC_PORT_MIN	0x40
 35#define DYNAMIC_PORT_MAX	0x7f
 36
 37static DEFINE_SEQLOCK(local_port_range_lock);
 38static int local_port_range_min[2] = {0, 0};
 39static int local_port_range_max[2] = {1023, 1023};
 40static int local_port_range[2] = {DYNAMIC_PORT_MIN, DYNAMIC_PORT_MAX};
 41static struct ctl_table_header *phonet_table_hrd;
 42
 43static void set_local_port_range(int range[2])
 44{
 45	write_seqlock(&local_port_range_lock);
 46	local_port_range[0] = range[0];
 47	local_port_range[1] = range[1];
 48	write_sequnlock(&local_port_range_lock);
 49}
 50
 51void phonet_get_local_port_range(int *min, int *max)
 52{
 53	unsigned int seq;
 54
 55	do {
 56		seq = read_seqbegin(&local_port_range_lock);
 57		if (min)
 58			*min = local_port_range[0];
 59		if (max)
 60			*max = local_port_range[1];
 61	} while (read_seqretry(&local_port_range_lock, seq));
 62}
 63
 64static int proc_local_port_range(struct ctl_table *table, int write,
 65				void __user *buffer,
 66				size_t *lenp, loff_t *ppos)
 67{
 68	int ret;
 69	int range[2] = {local_port_range[0], local_port_range[1]};
 70	struct ctl_table tmp = {
 71		.data = &range,
 72		.maxlen = sizeof(range),
 73		.mode = table->mode,
 74		.extra1 = &local_port_range_min,
 75		.extra2 = &local_port_range_max,
 76	};
 77
 78	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 79
 80	if (write && ret == 0) {
 81		if (range[1] < range[0])
 82			ret = -EINVAL;
 83		else
 84			set_local_port_range(range);
 85	}
 86
 87	return ret;
 88}
 89
 90static struct ctl_table phonet_table[] = {
 91	{
 92		.procname	= "local_port_range",
 93		.data		= &local_port_range,
 94		.maxlen		= sizeof(local_port_range),
 95		.mode		= 0644,
 96		.proc_handler	= proc_local_port_range,
 97	},
 98	{ }
 99};
100
101int __init phonet_sysctl_init(void)
102{
103	phonet_table_hrd = register_net_sysctl(&init_net, "net/phonet", phonet_table);
104	return phonet_table_hrd == NULL ? -ENOMEM : 0;
105}
106
107void phonet_sysctl_exit(void)
108{
109	unregister_net_sysctl_table(phonet_table_hrd);
110}