1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * File: sysctl.c
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Phonet /proc/sys/net/phonet interface implementation
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * Copyright (C) 2008 Nokia Corporation.
8*4882a593Smuzhiyun *
9*4882a593Smuzhiyun * Author: Rémi Denis-Courmont
10*4882a593Smuzhiyun */
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun #include <linux/seqlock.h>
13*4882a593Smuzhiyun #include <linux/sysctl.h>
14*4882a593Smuzhiyun #include <linux/errno.h>
15*4882a593Smuzhiyun #include <linux/init.h>
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun #include <net/sock.h>
18*4882a593Smuzhiyun #include <linux/phonet.h>
19*4882a593Smuzhiyun #include <net/phonet/phonet.h>
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun #define DYNAMIC_PORT_MIN 0x40
22*4882a593Smuzhiyun #define DYNAMIC_PORT_MAX 0x7f
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun static DEFINE_SEQLOCK(local_port_range_lock);
25*4882a593Smuzhiyun static int local_port_range_min[2] = {0, 0};
26*4882a593Smuzhiyun static int local_port_range_max[2] = {1023, 1023};
27*4882a593Smuzhiyun static int local_port_range[2] = {DYNAMIC_PORT_MIN, DYNAMIC_PORT_MAX};
28*4882a593Smuzhiyun static struct ctl_table_header *phonet_table_hrd;
29*4882a593Smuzhiyun
set_local_port_range(int range[2])30*4882a593Smuzhiyun static void set_local_port_range(int range[2])
31*4882a593Smuzhiyun {
32*4882a593Smuzhiyun write_seqlock(&local_port_range_lock);
33*4882a593Smuzhiyun local_port_range[0] = range[0];
34*4882a593Smuzhiyun local_port_range[1] = range[1];
35*4882a593Smuzhiyun write_sequnlock(&local_port_range_lock);
36*4882a593Smuzhiyun }
37*4882a593Smuzhiyun
phonet_get_local_port_range(int * min,int * max)38*4882a593Smuzhiyun void phonet_get_local_port_range(int *min, int *max)
39*4882a593Smuzhiyun {
40*4882a593Smuzhiyun unsigned int seq;
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun do {
43*4882a593Smuzhiyun seq = read_seqbegin(&local_port_range_lock);
44*4882a593Smuzhiyun if (min)
45*4882a593Smuzhiyun *min = local_port_range[0];
46*4882a593Smuzhiyun if (max)
47*4882a593Smuzhiyun *max = local_port_range[1];
48*4882a593Smuzhiyun } while (read_seqretry(&local_port_range_lock, seq));
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun
proc_local_port_range(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)51*4882a593Smuzhiyun static int proc_local_port_range(struct ctl_table *table, int write,
52*4882a593Smuzhiyun void *buffer, size_t *lenp, loff_t *ppos)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun int ret;
55*4882a593Smuzhiyun int range[2] = {local_port_range[0], local_port_range[1]};
56*4882a593Smuzhiyun struct ctl_table tmp = {
57*4882a593Smuzhiyun .data = &range,
58*4882a593Smuzhiyun .maxlen = sizeof(range),
59*4882a593Smuzhiyun .mode = table->mode,
60*4882a593Smuzhiyun .extra1 = &local_port_range_min,
61*4882a593Smuzhiyun .extra2 = &local_port_range_max,
62*4882a593Smuzhiyun };
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
65*4882a593Smuzhiyun
66*4882a593Smuzhiyun if (write && ret == 0) {
67*4882a593Smuzhiyun if (range[1] < range[0])
68*4882a593Smuzhiyun ret = -EINVAL;
69*4882a593Smuzhiyun else
70*4882a593Smuzhiyun set_local_port_range(range);
71*4882a593Smuzhiyun }
72*4882a593Smuzhiyun
73*4882a593Smuzhiyun return ret;
74*4882a593Smuzhiyun }
75*4882a593Smuzhiyun
76*4882a593Smuzhiyun static struct ctl_table phonet_table[] = {
77*4882a593Smuzhiyun {
78*4882a593Smuzhiyun .procname = "local_port_range",
79*4882a593Smuzhiyun .data = &local_port_range,
80*4882a593Smuzhiyun .maxlen = sizeof(local_port_range),
81*4882a593Smuzhiyun .mode = 0644,
82*4882a593Smuzhiyun .proc_handler = proc_local_port_range,
83*4882a593Smuzhiyun },
84*4882a593Smuzhiyun { }
85*4882a593Smuzhiyun };
86*4882a593Smuzhiyun
phonet_sysctl_init(void)87*4882a593Smuzhiyun int __init phonet_sysctl_init(void)
88*4882a593Smuzhiyun {
89*4882a593Smuzhiyun phonet_table_hrd = register_net_sysctl(&init_net, "net/phonet", phonet_table);
90*4882a593Smuzhiyun return phonet_table_hrd == NULL ? -ENOMEM : 0;
91*4882a593Smuzhiyun }
92*4882a593Smuzhiyun
phonet_sysctl_exit(void)93*4882a593Smuzhiyun void phonet_sysctl_exit(void)
94*4882a593Smuzhiyun {
95*4882a593Smuzhiyun unregister_net_sysctl_table(phonet_table_hrd);
96*4882a593Smuzhiyun }
97