// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 * Copyright (C) 1996 Mike Shaver (shaver@zeroknowledge.com)
 */
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/sysctl.h>
#include <linux/spinlock.h>
#include <net/ax25.h>

static int min_ipdefmode[1],            max_ipdefmode[] = {1};
static int min_axdefmode[1],            max_axdefmode[] = {1};
static int min_backoff[1],              max_backoff[] = {2};
static int min_conmode[1],              max_conmode[] = {2};
static int min_window[] = {1},          max_window[] = {7};
static int min_ewindow[] = {1},         max_ewindow[] = {63};
static int min_t1[] = {1},              max_t1[] = {30000};
static int min_t2[] = {1},              max_t2[] = {20000};
static int min_t3[1],                   max_t3[] = {3600000};
static int min_idle[1],                 max_idle[] = {65535000};
static int min_n2[] = {1},              max_n2[] = {31};
static int min_paclen[] = {1},          max_paclen[] = {512};
static int min_proto[1],                max_proto[] = { AX25_PROTO_MAX };
#ifdef CONFIG_AX25_DAMA_SLAVE
static int min_ds_timeout[1],           max_ds_timeout[] = {65535000};
#endif

static const struct ctl_table ax25_param_table[] = {
        {
                .procname       = "ip_default_mode",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_ipdefmode,
                .extra2         = &max_ipdefmode
        },
        {
                .procname       = "ax25_default_mode",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_axdefmode,
                .extra2         = &max_axdefmode
        },
        {
                .procname       = "backoff_type",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_backoff,
                .extra2         = &max_backoff
        },
        {
                .procname       = "connect_mode",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_conmode,
                .extra2         = &max_conmode
        },
        {
                .procname       = "standard_window_size",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_window,
                .extra2         = &max_window
        },
        {
                .procname       = "extended_window_size",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_ewindow,
                .extra2         = &max_ewindow
        },
        {
                .procname       = "t1_timeout",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_t1,
                .extra2         = &max_t1
        },
        {
                .procname       = "t2_timeout",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_t2,
                .extra2         = &max_t2
        },
        {
                .procname       = "t3_timeout",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_t3,
                .extra2         = &max_t3
        },
        {
                .procname       = "idle_timeout",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_idle,
                .extra2         = &max_idle
        },
        {
                .procname       = "maximum_retry_count",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_n2,
                .extra2         = &max_n2
        },
        {
                .procname       = "maximum_packet_length",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_paclen,
                .extra2         = &max_paclen
        },
        {
                .procname       = "protocol",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_proto,
                .extra2         = &max_proto
        },
#ifdef CONFIG_AX25_DAMA_SLAVE
        {
                .procname       = "dama_slave_timeout",
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = &min_ds_timeout,
                .extra2         = &max_ds_timeout
        },
#endif
};

int ax25_register_dev_sysctl(ax25_dev *ax25_dev)
{
        char path[sizeof("net/ax25/") + IFNAMSIZ];
        int k;
        struct ctl_table *table;

        table = kmemdup(ax25_param_table, sizeof(ax25_param_table), GFP_KERNEL);
        if (!table)
                return -ENOMEM;

        BUILD_BUG_ON(ARRAY_SIZE(ax25_param_table) != AX25_MAX_VALUES);
        for (k = 0; k < AX25_MAX_VALUES; k++)
                table[k].data = &ax25_dev->values[k];

        snprintf(path, sizeof(path), "net/ax25/%s", ax25_dev->dev->name);
        ax25_dev->sysheader = register_net_sysctl_sz(&init_net, path, table,
                                                     ARRAY_SIZE(ax25_param_table));
        if (!ax25_dev->sysheader) {
                kfree(table);
                return -ENOMEM;
        }
        return 0;
}

void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev)
{
        struct ctl_table_header *header = ax25_dev->sysheader;
        const struct ctl_table *table;

        if (header) {
                ax25_dev->sysheader = NULL;
                table = header->ctl_table_arg;
                unregister_net_sysctl_table(header);
                kfree(table);
        }
}