[thirdparty/kernel/linux.git] / net / mptcp / 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;

#ifdef CONFIG_SYSCTL
static int mptcp_pm_type_max = __MPTCP_PM_TYPE_MAX;
#endif

struct mptcp_pernet {
#ifdef CONFIG_SYSCTL
	struct ctl_table_header *ctl_table_hdr;
#endif

	unsigned int add_addr_timeout;
	unsigned int close_timeout;
	unsigned int stale_loss_cnt;
	u8 mptcp_enabled;
	u8 checksum_enabled;
	u8 allow_join_initial_addr_port;
	u8 pm_type;
	char scheduler[MPTCP_SCHED_NAME_MAX];
};

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;
}

unsigned int mptcp_close_timeout(const struct sock *sk)
{
	if (sock_flag(sk, SOCK_DEAD))
		return TCP_TIMEWAIT_LEN;
	return mptcp_get_pernet(sock_net(sk))->close_timeout;
}

int mptcp_get_pm_type(const struct net *net)
{
	return mptcp_get_pernet(net)->pm_type;
}

const char *mptcp_get_scheduler(const struct net *net)
{
	return mptcp_get_pernet(net)->scheduler;
}

static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet)
{
	pernet->mptcp_enabled = 1;
	pernet->add_addr_timeout = TCP_RTO_MAX;
	pernet->close_timeout = TCP_TIMEWAIT_LEN;
	pernet->checksum_enabled = 0;
	pernet->allow_join_initial_addr_port = 1;
	pernet->stale_loss_cnt = 4;
	pernet->pm_type = MPTCP_PM_TYPE_KERNEL;
	strscpy(pernet->scheduler, "default", sizeof(pernet->scheduler));
}

#ifdef CONFIG_SYSCTL
static int mptcp_set_scheduler(const struct net *net, const char *name)
{
	struct mptcp_pernet *pernet = mptcp_get_pernet(net);
	struct mptcp_sched_ops *sched;
	int ret = 0;

	rcu_read_lock();
	sched = mptcp_sched_find(name);
	if (sched)
		strscpy(pernet->scheduler, name, MPTCP_SCHED_NAME_MAX);
	else
		ret = -ENOENT;
	rcu_read_unlock();

	return ret;
}

static int proc_scheduler(struct ctl_table *ctl, int write,
			  void *buffer, size_t *lenp, loff_t *ppos)
{
	const struct net *net = current->nsproxy->net_ns;
	char val[MPTCP_SCHED_NAME_MAX];
	struct ctl_table tbl = {
		.data = val,
		.maxlen = MPTCP_SCHED_NAME_MAX,
	};
	int ret;

	strscpy(val, mptcp_get_scheduler(net), MPTCP_SCHED_NAME_MAX);

	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
	if (write && ret == 0)
		ret = mptcp_set_scheduler(net, val);

	return ret;
}

static int proc_available_schedulers(struct ctl_table *ctl,
				     int write, void *buffer,
				     size_t *lenp, loff_t *ppos)
{
	struct ctl_table tbl = { .maxlen = MPTCP_SCHED_BUF_MAX, };
	int ret;

	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
	if (!tbl.data)
		return -ENOMEM;

	mptcp_get_available_schedulers(tbl.data, MPTCP_SCHED_BUF_MAX);
	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
	kfree(tbl.data);

	return ret;
}

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,
	},
	{
		.procname = "pm_type",
		.maxlen = sizeof(u8),
		.mode = 0644,
		.proc_handler = proc_dou8vec_minmax,
		.extra1       = SYSCTL_ZERO,
		.extra2       = &mptcp_pm_type_max
	},
	{
		.procname = "scheduler",
		.maxlen	= MPTCP_SCHED_NAME_MAX,
		.mode = 0644,
		.proc_handler = proc_scheduler,
	},
	{
		.procname = "available_schedulers",
		.maxlen	= MPTCP_SCHED_BUF_MAX,
		.mode = 0644,
		.proc_handler = proc_available_schedulers,
	},
	{
		.procname = "close_timeout",
		.maxlen = sizeof(unsigned int),
		.mode = 0644,
		.proc_handler = proc_dointvec_jiffies,
	},
};

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;
	table[5].data = &pernet->pm_type;
	table[6].data = &pernet->scheduler;
	/* table[7] is for available_schedulers which is read-only info */
	table[8].data = &pernet->close_timeout;

	hdr = register_net_sysctl_sz(net, MPTCP_SYSCTL_PATH, table,
				     ARRAY_SIZE(mptcp_sysctl_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)
{
	const 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
Commit	Line	Data
784325e9 MB	1	// SPDX-License-Identifier: GPL-2.0
	2	/* Multipath TCP
	3	*
	4	* Copyright (c) 2019, Tessares SA.
	5	*/
	6
804c72ee	7	#ifdef CONFIG_SYSCTL
784325e9	8	#include <linux/sysctl.h>
804c72ee	9	#endif
784325e9 MB	10
	11	#include <net/net_namespace.h>
	12	#include <net/netns/generic.h>
	13
	14	#include "protocol.h"
	15
	16	#define MPTCP_SYSCTL_PATH "net/mptcp"
	17
	18	static int mptcp_pernet_id;
6bb63ccc MM	19
	20	#ifdef CONFIG_SYSCTL
	21	static int mptcp_pm_type_max = __MPTCP_PM_TYPE_MAX;
	22	#endif
	23
784325e9	24	struct mptcp_pernet {
804c72ee	25	#ifdef CONFIG_SYSCTL
784325e9	26	struct ctl_table_header *ctl_table_hdr;
804c72ee	27	#endif
784325e9	28
93f323b9	29	unsigned int add_addr_timeout;
d866ae9a	30	unsigned int close_timeout;
ff5a0b42	31	unsigned int stale_loss_cnt;
6da14d74	32	u8 mptcp_enabled;
fc3c82ee	33	u8 checksum_enabled;
d2f77960	34	u8 allow_join_initial_addr_port;
6bb63ccc	35	u8 pm_type;
e3b2870b	36	char scheduler[MPTCP_SCHED_NAME_MAX];
784325e9 MB	37	};
784325e9 MB	38
6da14d74	39	static struct mptcp_pernet mptcp_get_pernet(const struct net net)
784325e9 MB	40	{
	41	return net_generic(net, mptcp_pernet_id);
	42	}
	43
6da14d74	44	int mptcp_is_enabled(const struct net *net)
784325e9 MB	45	{
	46	return mptcp_get_pernet(net)->mptcp_enabled;
	47	}
	48
6da14d74	49	unsigned int mptcp_get_add_addr_timeout(const struct net *net)
93f323b9 GT	50	{
	51	return mptcp_get_pernet(net)->add_addr_timeout;
	52	}
	53
6da14d74	54	int mptcp_is_checksum_enabled(const struct net *net)
fc3c82ee GT	55	{
	56	return mptcp_get_pernet(net)->checksum_enabled;
	57	}
	58
6da14d74	59	int mptcp_allow_join_id0(const struct net *net)
d2f77960 GT	60	{
	61	return mptcp_get_pernet(net)->allow_join_initial_addr_port;
	62	}
	63
ff5a0b42 PA	64	unsigned int mptcp_stale_loss_cnt(const struct net *net)
	65	{
	66	return mptcp_get_pernet(net)->stale_loss_cnt;
	67	}
	68
d866ae9a PA	69	unsigned int mptcp_close_timeout(const struct sock *sk)
	70	{
	71	if (sock_flag(sk, SOCK_DEAD))
	72	return TCP_TIMEWAIT_LEN;
	73	return mptcp_get_pernet(sock_net(sk))->close_timeout;
	74	}
	75
6bb63ccc MM	76	int mptcp_get_pm_type(const struct net *net)
	77	{
	78	return mptcp_get_pernet(net)->pm_type;
	79	}
	80
e3b2870b GT	81	const char mptcp_get_scheduler(const struct net net)
	82	{
	83	return mptcp_get_pernet(net)->scheduler;
	84	}
	85
804c72ee MB	86	static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet)
	87	{
	88	pernet->mptcp_enabled = 1;
	89	pernet->add_addr_timeout = TCP_RTO_MAX;
d866ae9a	90	pernet->close_timeout = TCP_TIMEWAIT_LEN;
fc3c82ee	91	pernet->checksum_enabled = 0;
d2f77960	92	pernet->allow_join_initial_addr_port = 1;
ff5a0b42	93	pernet->stale_loss_cnt = 4;
6bb63ccc	94	pernet->pm_type = MPTCP_PM_TYPE_KERNEL;
5eae7a82	95	strscpy(pernet->scheduler, "default", sizeof(pernet->scheduler));
804c72ee MB	96	}
	97
	98	#ifdef CONFIG_SYSCTL
6963c508 GD	99	static int mptcp_set_scheduler(const struct net net, const char name)
	100	{
	101	struct mptcp_pernet *pernet = mptcp_get_pernet(net);
	102	struct mptcp_sched_ops *sched;
	103	int ret = 0;
	104
	105	rcu_read_lock();
	106	sched = mptcp_sched_find(name);
	107	if (sched)
	108	strscpy(pernet->scheduler, name, MPTCP_SCHED_NAME_MAX);
	109	else
	110	ret = -ENOENT;
	111	rcu_read_unlock();
	112
	113	return ret;
	114	}
	115
	116	static int proc_scheduler(struct ctl_table *ctl, int write,
	117	void buffer, size_t lenp, loff_t *ppos)
	118	{
	119	const struct net *net = current->nsproxy->net_ns;
	120	char val[MPTCP_SCHED_NAME_MAX];
	121	struct ctl_table tbl = {
	122	.data = val,
	123	.maxlen = MPTCP_SCHED_NAME_MAX,
	124	};
	125	int ret;
	126
	127	strscpy(val, mptcp_get_scheduler(net), MPTCP_SCHED_NAME_MAX);
	128
	129	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
	130	if (write && ret == 0)
	131	ret = mptcp_set_scheduler(net, val);
	132
	133	return ret;
	134	}
	135
73c900aa GD	136	static int proc_available_schedulers(struct ctl_table *ctl,
	137	int write, void *buffer,
	138	size_t lenp, loff_t ppos)
	139	{
	140	struct ctl_table tbl = { .maxlen = MPTCP_SCHED_BUF_MAX, };
	141	int ret;
	142
	143	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
	144	if (!tbl.data)
	145	return -ENOMEM;
	146
	147	mptcp_get_available_schedulers(tbl.data, MPTCP_SCHED_BUF_MAX);
	148	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
	149	kfree(tbl.data);
	150
	151	return ret;
	152	}
	153
784325e9 MB	154	static struct ctl_table mptcp_sysctl_table[] = {
	155	{
	156	.procname = "enabled",
744ee140	157	.maxlen = sizeof(u8),
784325e9 MB	158	.mode = 0644,
	159	/* users with CAP_NET_ADMIN or root (not and) can change this
	160	* value, same as other sysctl or the 'net' tree.
	161	*/
744ee140 MB	162	.proc_handler = proc_dou8vec_minmax,
	163	.extra1 = SYSCTL_ZERO,
	164	.extra2 = SYSCTL_ONE
784325e9	165	},
93f323b9 GT	166	{
	167	.procname = "add_addr_timeout",
	168	.maxlen = sizeof(unsigned int),
	169	.mode = 0644,
	170	.proc_handler = proc_dointvec_jiffies,
	171	},
fc3c82ee GT	172	{
	173	.procname = "checksum_enabled",
	174	.maxlen = sizeof(u8),
	175	.mode = 0644,
	176	.proc_handler = proc_dou8vec_minmax,
	177	.extra1 = SYSCTL_ZERO,
	178	.extra2 = SYSCTL_ONE
	179	},
d2f77960 GT	180	{
	181	.procname = "allow_join_initial_addr_port",
	182	.maxlen = sizeof(u8),
	183	.mode = 0644,
	184	.proc_handler = proc_dou8vec_minmax,
	185	.extra1 = SYSCTL_ZERO,
	186	.extra2 = SYSCTL_ONE
	187	},
ff5a0b42 PA	188	{
	189	.procname = "stale_loss_cnt",
	190	.maxlen = sizeof(unsigned int),
	191	.mode = 0644,
	192	.proc_handler = proc_douintvec_minmax,
	193	},
6bb63ccc MM	194	{
	195	.procname = "pm_type",
	196	.maxlen = sizeof(u8),
	197	.mode = 0644,
	198	.proc_handler = proc_dou8vec_minmax,
	199	.extra1 = SYSCTL_ZERO,
	200	.extra2 = &mptcp_pm_type_max
	201	},
e3b2870b GT	202	{
	203	.procname = "scheduler",
	204	.maxlen = MPTCP_SCHED_NAME_MAX,
	205	.mode = 0644,
6963c508	206	.proc_handler = proc_scheduler,
e3b2870b	207	},
73c900aa GD	208	{
	209	.procname = "available_schedulers",
	210	.maxlen = MPTCP_SCHED_BUF_MAX,
	211	.mode = 0644,
	212	.proc_handler = proc_available_schedulers,
	213	},
d866ae9a PA	214	{
	215	.procname = "close_timeout",
	216	.maxlen = sizeof(unsigned int),
	217	.mode = 0644,
	218	.proc_handler = proc_dointvec_jiffies,
	219	},
784325e9 MB	220	};
784325e9 MB	221
784325e9 MB	222	static int mptcp_pernet_new_table(struct net net, struct mptcp_pernet pernet)
	223	{
	224	struct ctl_table_header *hdr;
	225	struct ctl_table *table;
	226
	227	table = mptcp_sysctl_table;
	228	if (!net_eq(net, &init_net)) {
	229	table = kmemdup(table, sizeof(mptcp_sysctl_table), GFP_KERNEL);
	230	if (!table)
	231	goto err_alloc;
	232	}
	233
	234	table[0].data = &pernet->mptcp_enabled;
93f323b9	235	table[1].data = &pernet->add_addr_timeout;
fc3c82ee	236	table[2].data = &pernet->checksum_enabled;
d2f77960	237	table[3].data = &pernet->allow_join_initial_addr_port;
ff5a0b42	238	table[4].data = &pernet->stale_loss_cnt;
6bb63ccc	239	table[5].data = &pernet->pm_type;
e3b2870b	240	table[6].data = &pernet->scheduler;
73c900aa GD	241	/* table[7] is for available_schedulers which is read-only info */
73c900aa GD	242	table[8].data = &pernet->close_timeout;
784325e9	243
c899710f JG	244	hdr = register_net_sysctl_sz(net, MPTCP_SYSCTL_PATH, table,
c899710f JG	245	ARRAY_SIZE(mptcp_sysctl_table));
784325e9 MB	246	if (!hdr)
	247	goto err_reg;
	248
	249	pernet->ctl_table_hdr = hdr;
	250
	251	return 0;
	252
	253	err_reg:
	254	if (!net_eq(net, &init_net))
	255	kfree(table);
	256	err_alloc:
	257	return -ENOMEM;
	258	}
	259
	260	static void mptcp_pernet_del_table(struct mptcp_pernet *pernet)
	261	{
bfa858f2	262	const struct ctl_table *table = pernet->ctl_table_hdr->ctl_table_arg;
784325e9 MB	263
	264	unregister_net_sysctl_table(pernet->ctl_table_hdr);
	265
	266	kfree(table);
	267	}
	268
804c72ee MB	269	#else
	270
	271	static int mptcp_pernet_new_table(struct net net, struct mptcp_pernet pernet)
	272	{
	273	return 0;
	274	}
	275
	276	static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) {}
	277
	278	#endif /* CONFIG_SYSCTL */
	279
784325e9 MB	280	static int __net_init mptcp_net_init(struct net *net)
	281	{
	282	struct mptcp_pernet *pernet = mptcp_get_pernet(net);
	283
	284	mptcp_pernet_set_defaults(pernet);
	285
	286	return mptcp_pernet_new_table(net, pernet);
	287	}
	288
	289	/* Note: the callback will only be called per extra netns */
	290	static void __net_exit mptcp_net_exit(struct net *net)
	291	{
	292	struct mptcp_pernet *pernet = mptcp_get_pernet(net);
	293
	294	mptcp_pernet_del_table(pernet);
	295	}
	296
	297	static struct pernet_operations mptcp_pernet_ops = {
	298	.init = mptcp_net_init,
	299	.exit = mptcp_net_exit,
	300	.id = &mptcp_pernet_id,
	301	.size = sizeof(struct mptcp_pernet),
	302	};
	303
	304	void __init mptcp_init(void)
	305	{
9466a1cc	306	mptcp_join_cookie_init();
784325e9 MB	307	mptcp_proto_init();
	308
	309	if (register_pernet_subsys(&mptcp_pernet_ops) < 0)
	310	panic("Failed to register MPTCP pernet subsystem.\n");
	311	}
	312
	313	#if IS_ENABLED(CONFIG_MPTCP_IPV6)
	314	int __init mptcpv6_init(void)
	315	{
	316	int err;
	317
	318	err = mptcp_proto_v6_init();
	319
	320	return err;
	321	}
	322	#endif