ctrl.c
// SPDX-License-Identifier: GPL-2.0
/* Multipath TCP
*
* Copyright (c) 2019, Tessares SA.
*/
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include "protocol.h"
#define MPTCP_SYSCTL_PATH "net/mptcp"
static int mptcp_pernet_id;
struct mptcp_pernet {
#ifdef CONFIG_SYSCTL
struct ctl_table_header *ctl_table_hdr;
#endif
unsigned int add_addr_timeout;
unsigned int stale_loss_cnt;
u8 mptcp_enabled;
u8 checksum_enabled;
u8 allow_join_initial_addr_port;
};
static struct mptcp_pernet *mptcp_get_pernet(const struct net *net)
{
return net_generic(net, mptcp_pernet_id);
}
int mptcp_is_enabled(const struct net *net)
{
return mptcp_get_pernet(net)->mptcp_enabled;
}
unsigned int mptcp_get_add_addr_timeout(const struct net *net)
{
return mptcp_get_pernet(net)->add_addr_timeout;
}
int mptcp_is_checksum_enabled(const struct net *net)
{
return mptcp_get_pernet(net)->checksum_enabled;
}
int mptcp_allow_join_id0(const struct net *net)
{
return mptcp_get_pernet(net)->allow_join_initial_addr_port;
}
unsigned int mptcp_stale_loss_cnt(const struct net *net)
{
return mptcp_get_pernet(net)->stale_loss_cnt;
}
static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet)
{
pernet->mptcp_enabled = 1;
pernet->add_addr_timeout = TCP_RTO_MAX;
pernet->checksum_enabled = 0;
pernet->allow_join_initial_addr_port = 1;
pernet->stale_loss_cnt = 4;
}
#ifdef CONFIG_SYSCTL
static struct ctl_table mptcp_sysctl_table[] = {
{
.procname = "enabled",
.maxlen = sizeof(u8),
.mode = 0644,
/* users with CAP_NET_ADMIN or root (not and) can change this
* value, same as other sysctl or the 'net' tree.
*/
.proc_handler = proc_dou8vec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE
},
{
.procname = "add_addr_timeout",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "checksum_enabled",
.maxlen = sizeof(u8),
.mode = 0644,
.proc_handler = proc_dou8vec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE
},
{
.procname = "allow_join_initial_addr_port",
.maxlen = sizeof(u8),
.mode = 0644,
.proc_handler = proc_dou8vec_minmax,
.extra1 = SYSCTL_ZERO,
.extra2 = SYSCTL_ONE
},
{
.procname = "stale_loss_cnt",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_douintvec_minmax,
},
{}
};
static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet)
{
struct ctl_table_header *hdr;
struct ctl_table *table;
table = mptcp_sysctl_table;
if (!net_eq(net, &init_net)) {
table = kmemdup(table, sizeof(mptcp_sysctl_table), GFP_KERNEL);
if (!table)
goto err_alloc;
}
table[0].data = &pernet->mptcp_enabled;
table[1].data = &pernet->add_addr_timeout;
table[2].data = &pernet->checksum_enabled;
table[3].data = &pernet->allow_join_initial_addr_port;
table[4].data = &pernet->stale_loss_cnt;
hdr = register_net_sysctl(net, MPTCP_SYSCTL_PATH, table);
if (!hdr)
goto err_reg;
pernet->ctl_table_hdr = hdr;
return 0;
err_reg:
if (!net_eq(net, &init_net))
kfree(table);
err_alloc:
return -ENOMEM;
}
static void mptcp_pernet_del_table(struct mptcp_pernet *pernet)
{
struct ctl_table *table = pernet->ctl_table_hdr->ctl_table_arg;
unregister_net_sysctl_table(pernet->ctl_table_hdr);
kfree(table);
}
#else
static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet)
{
return 0;
}
static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) {}
#endif /* CONFIG_SYSCTL */
static int __net_init mptcp_net_init(struct net *net)
{
struct mptcp_pernet *pernet = mptcp_get_pernet(net);
mptcp_pernet_set_defaults(pernet);
return mptcp_pernet_new_table(net, pernet);
}
/* Note: the callback will only be called per extra netns */
static void __net_exit mptcp_net_exit(struct net *net)
{
struct mptcp_pernet *pernet = mptcp_get_pernet(net);
mptcp_pernet_del_table(pernet);
}
static struct pernet_operations mptcp_pernet_ops = {
.init = mptcp_net_init,
.exit = mptcp_net_exit,
.id = &mptcp_pernet_id,
.size = sizeof(struct mptcp_pernet),
};
void __init mptcp_init(void)
{
mptcp_join_cookie_init();
mptcp_proto_init();
if (register_pernet_subsys(&mptcp_pernet_ops) < 0)
panic("Failed to register MPTCP pernet subsystem.\n");
}
#if IS_ENABLED(CONFIG_MPTCP_IPV6)
int __init mptcpv6_init(void)
{
int err;
err = mptcp_proto_v6_init();
return err;
}
#endif