linux/net/ipv4/sysctl_net_ipv4.c
Maciej Żenczykowski 79e9fed460 net-tcp: extend tcp_tw_reuse sysctl to enable loopback only optimization
This changes the /proc/sys/net/ipv4/tcp_tw_reuse from a boolean
to an integer.

It now takes the values 0, 1 and 2, where 0 and 1 behave as before,
while 2 enables timewait socket reuse only for sockets that we can
prove are loopback connections:
  ie. bound to 'lo' interface or where one of source or destination
  IPs is 127.0.0.0/8, ::ffff:127.0.0.0/104 or ::1.

This enables quicker reuse of ephemeral ports for loopback connections
- where tcp_tw_reuse is 100% safe from a protocol perspective
(this assumes no artificially induced packet loss on 'lo').

This also makes estblishing many loopback connections *much* faster
(allocating ports out of the first half of the ephemeral port range
is significantly faster, then allocating from the second half)

Without this change in a 32K ephemeral port space my sample program
(it just establishes and closes [::1]:ephemeral -> [::1]:server_port
connections in a tight loop) fails after 32765 connections in 24 seconds.
With it enabled 50000 connections only take 4.7 seconds.

This is particularly problematic for IPv6 where we only have one local
address and cannot play tricks with varying source IP from 127.0.0.0/8
pool.

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Wei Wang <weiwan@google.com>
Change-Id: I0377961749979d0301b7b62871a32a4b34b654e1
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-04 17:13:35 -04:00

1261 lines
31 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
*
* Begun April 1, 1996, Mike Shaver.
* Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
*/
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/sysctl.h>
#include <linux/igmp.h>
#include <linux/inetdevice.h>
#include <linux/seqlock.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/nsproxy.h>
#include <linux/swap.h>
#include <net/snmp.h>
#include <net/icmp.h>
#include <net/ip.h>
#include <net/route.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/cipso_ipv4.h>
#include <net/inet_frag.h>
#include <net/ping.h>
#include <net/protocol.h>
#include <net/netevent.h>
static int zero;
static int one = 1;
static int two = 2;
static int four = 4;
static int thousand = 1000;
static int gso_max_segs = GSO_MAX_SEGS;
static int tcp_retr1_max = 255;
static int ip_local_port_range_min[] = { 1, 1 };
static int ip_local_port_range_max[] = { 65535, 65535 };
static int tcp_adv_win_scale_min = -31;
static int tcp_adv_win_scale_max = 31;
static int ip_privileged_port_min;
static int ip_privileged_port_max = 65535;
static int ip_ttl_min = 1;
static int ip_ttl_max = 255;
static int tcp_syn_retries_min = 1;
static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
static int ip_ping_group_range_min[] = { 0, 0 };
static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
static int comp_sack_nr_max = 255;
/* obsolete */
static int sysctl_tcp_low_latency __read_mostly;
/* Update system visible IP port range */
static void set_local_port_range(struct net *net, int range[2])
{
bool same_parity = !((range[0] ^ range[1]) & 1);
write_seqlock_bh(&net->ipv4.ip_local_ports.lock);
if (same_parity && !net->ipv4.ip_local_ports.warned) {
net->ipv4.ip_local_ports.warned = true;
pr_err_ratelimited("ip_local_port_range: prefer different parity for start/end values.\n");
}
net->ipv4.ip_local_ports.range[0] = range[0];
net->ipv4.ip_local_ports.range[1] = range[1];
write_sequnlock_bh(&net->ipv4.ip_local_ports.lock);
}
/* Validate changes from /proc interface. */
static int ipv4_local_port_range(struct ctl_table *table, int write,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
struct net *net =
container_of(table->data, struct net, ipv4.ip_local_ports.range);
int ret;
int range[2];
struct ctl_table tmp = {
.data = &range,
.maxlen = sizeof(range),
.mode = table->mode,
.extra1 = &ip_local_port_range_min,
.extra2 = &ip_local_port_range_max,
};
inet_get_local_port_range(net, &range[0], &range[1]);
ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
if (write && ret == 0) {
/* Ensure that the upper limit is not smaller than the lower,
* and that the lower does not encroach upon the privileged
* port limit.
*/
if ((range[1] < range[0]) ||
(range[0] < net->ipv4.sysctl_ip_prot_sock))
ret = -EINVAL;
else
set_local_port_range(net, range);
}
return ret;
}
/* Validate changes from /proc interface. */
static int ipv4_privileged_ports(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct net *net = container_of(table->data, struct net,
ipv4.sysctl_ip_prot_sock);
int ret;
int pports;
int range[2];
struct ctl_table tmp = {
.data = &pports,
.maxlen = sizeof(pports),
.mode = table->mode,
.extra1 = &ip_privileged_port_min,
.extra2 = &ip_privileged_port_max,
};
pports = net->ipv4.sysctl_ip_prot_sock;
ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
if (write && ret == 0) {
inet_get_local_port_range(net, &range[0], &range[1]);
/* Ensure that the local port range doesn't overlap with the
* privileged port range.
*/
if (range[0] < pports)
ret = -EINVAL;
else
net->ipv4.sysctl_ip_prot_sock = pports;
}
return ret;
}
static void inet_get_ping_group_range_table(struct ctl_table *table, kgid_t *low, kgid_t *high)
{
kgid_t *data = table->data;
struct net *net =
container_of(table->data, struct net, ipv4.ping_group_range.range);
unsigned int seq;
do {
seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
*low = data[0];
*high = data[1];
} while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
}
/* Update system visible IP port range */
static void set_ping_group_range(struct ctl_table *table, kgid_t low, kgid_t high)
{
kgid_t *data = table->data;
struct net *net =
container_of(table->data, struct net, ipv4.ping_group_range.range);
write_seqlock(&net->ipv4.ping_group_range.lock);
data[0] = low;
data[1] = high;
write_sequnlock(&net->ipv4.ping_group_range.lock);
}
/* Validate changes from /proc interface. */
static int ipv4_ping_group_range(struct ctl_table *table, int write,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
struct user_namespace *user_ns = current_user_ns();
int ret;
gid_t urange[2];
kgid_t low, high;
struct ctl_table tmp = {
.data = &urange,
.maxlen = sizeof(urange),
.mode = table->mode,
.extra1 = &ip_ping_group_range_min,
.extra2 = &ip_ping_group_range_max,
};
inet_get_ping_group_range_table(table, &low, &high);
urange[0] = from_kgid_munged(user_ns, low);
urange[1] = from_kgid_munged(user_ns, high);
ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
if (write && ret == 0) {
low = make_kgid(user_ns, urange[0]);
high = make_kgid(user_ns, urange[1]);
if (!gid_valid(low) || !gid_valid(high) ||
(urange[1] < urange[0]) || gid_lt(high, low)) {
low = make_kgid(&init_user_ns, 1);
high = make_kgid(&init_user_ns, 0);
}
set_ping_group_range(table, low, high);
}
return ret;
}
static int proc_tcp_congestion_control(struct ctl_table *ctl, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
struct net *net = container_of(ctl->data, struct net,
ipv4.tcp_congestion_control);
char val[TCP_CA_NAME_MAX];
struct ctl_table tbl = {
.data = val,
.maxlen = TCP_CA_NAME_MAX,
};
int ret;
tcp_get_default_congestion_control(net, val);
ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
if (write && ret == 0)
ret = tcp_set_default_congestion_control(net, val);
return ret;
}
static int proc_tcp_available_congestion_control(struct ctl_table *ctl,
int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
int ret;
tbl.data = kmalloc(tbl.maxlen, GFP_USER);
if (!tbl.data)
return -ENOMEM;
tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
kfree(tbl.data);
return ret;
}
static int proc_allowed_congestion_control(struct ctl_table *ctl,
int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
int ret;
tbl.data = kmalloc(tbl.maxlen, GFP_USER);
if (!tbl.data)
return -ENOMEM;
tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
if (write && ret == 0)
ret = tcp_set_allowed_congestion_control(tbl.data);
kfree(tbl.data);
return ret;
}
static int proc_tcp_fastopen_key(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
struct net *net = container_of(table->data, struct net,
ipv4.sysctl_tcp_fastopen);
struct ctl_table tbl = { .maxlen = (TCP_FASTOPEN_KEY_LENGTH * 2 + 10) };
struct tcp_fastopen_context *ctxt;
int ret;
u32 user_key[4]; /* 16 bytes, matching TCP_FASTOPEN_KEY_LENGTH */
tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
if (!tbl.data)
return -ENOMEM;
rcu_read_lock();
ctxt = rcu_dereference(net->ipv4.tcp_fastopen_ctx);
if (ctxt)
memcpy(user_key, ctxt->key, TCP_FASTOPEN_KEY_LENGTH);
else
memset(user_key, 0, sizeof(user_key));
rcu_read_unlock();
snprintf(tbl.data, tbl.maxlen, "%08x-%08x-%08x-%08x",
user_key[0], user_key[1], user_key[2], user_key[3]);
ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
if (write && ret == 0) {
if (sscanf(tbl.data, "%x-%x-%x-%x", user_key, user_key + 1,
user_key + 2, user_key + 3) != 4) {
ret = -EINVAL;
goto bad_key;
}
tcp_fastopen_reset_cipher(net, NULL, user_key,
TCP_FASTOPEN_KEY_LENGTH);
}
bad_key:
pr_debug("proc FO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
user_key[0], user_key[1], user_key[2], user_key[3],
(char *)tbl.data, ret);
kfree(tbl.data);
return ret;
}
static void proc_configure_early_demux(int enabled, int protocol)
{
struct net_protocol *ipprot;
#if IS_ENABLED(CONFIG_IPV6)
struct inet6_protocol *ip6prot;
#endif
rcu_read_lock();
ipprot = rcu_dereference(inet_protos[protocol]);
if (ipprot)
ipprot->early_demux = enabled ? ipprot->early_demux_handler :
NULL;
#if IS_ENABLED(CONFIG_IPV6)
ip6prot = rcu_dereference(inet6_protos[protocol]);
if (ip6prot)
ip6prot->early_demux = enabled ? ip6prot->early_demux_handler :
NULL;
#endif
rcu_read_unlock();
}
static int proc_tcp_early_demux(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
int ret = 0;
ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (write && !ret) {
int enabled = init_net.ipv4.sysctl_tcp_early_demux;
proc_configure_early_demux(enabled, IPPROTO_TCP);
}
return ret;
}
static int proc_udp_early_demux(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
int ret = 0;
ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (write && !ret) {
int enabled = init_net.ipv4.sysctl_udp_early_demux;
proc_configure_early_demux(enabled, IPPROTO_UDP);
}
return ret;
}
static int proc_tfo_blackhole_detect_timeout(struct ctl_table *table,
int write,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
struct net *net = container_of(table->data, struct net,
ipv4.sysctl_tcp_fastopen_blackhole_timeout);
int ret;
ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
if (write && ret == 0)
atomic_set(&net->ipv4.tfo_active_disable_times, 0);
return ret;
}
static int proc_tcp_available_ulp(struct ctl_table *ctl,
int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
struct ctl_table tbl = { .maxlen = TCP_ULP_BUF_MAX, };
int ret;
tbl.data = kmalloc(tbl.maxlen, GFP_USER);
if (!tbl.data)
return -ENOMEM;
tcp_get_available_ulp(tbl.data, TCP_ULP_BUF_MAX);
ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
kfree(tbl.data);
return ret;
}
#ifdef CONFIG_IP_ROUTE_MULTIPATH
static int proc_fib_multipath_hash_policy(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
struct net *net = container_of(table->data, struct net,
ipv4.sysctl_fib_multipath_hash_policy);
int ret;
ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
if (write && ret == 0)
call_netevent_notifiers(NETEVENT_IPV4_MPATH_HASH_UPDATE, net);
return ret;
}
#endif
static struct ctl_table ipv4_table[] = {
{
.procname = "tcp_max_orphans",
.data = &sysctl_tcp_max_orphans,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "inet_peer_threshold",
.data = &inet_peer_threshold,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "inet_peer_minttl",
.data = &inet_peer_minttl,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "inet_peer_maxttl",
.data = &inet_peer_maxttl,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "tcp_mem",
.maxlen = sizeof(sysctl_tcp_mem),
.data = &sysctl_tcp_mem,
.mode = 0644,
.proc_handler = proc_doulongvec_minmax,
},
{
.procname = "tcp_low_latency",
.data = &sysctl_tcp_low_latency,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
#ifdef CONFIG_NETLABEL
{
.procname = "cipso_cache_enable",
.data = &cipso_v4_cache_enabled,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "cipso_cache_bucket_size",
.data = &cipso_v4_cache_bucketsize,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "cipso_rbm_optfmt",
.data = &cipso_v4_rbm_optfmt,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "cipso_rbm_strictvalid",
.data = &cipso_v4_rbm_strictvalid,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
#endif /* CONFIG_NETLABEL */
{
.procname = "tcp_available_congestion_control",
.maxlen = TCP_CA_BUF_MAX,
.mode = 0444,
.proc_handler = proc_tcp_available_congestion_control,
},
{
.procname = "tcp_allowed_congestion_control",
.maxlen = TCP_CA_BUF_MAX,
.mode = 0644,
.proc_handler = proc_allowed_congestion_control,
},
{
.procname = "tcp_available_ulp",
.maxlen = TCP_ULP_BUF_MAX,
.mode = 0444,
.proc_handler = proc_tcp_available_ulp,
},
{
.procname = "icmp_msgs_per_sec",
.data = &sysctl_icmp_msgs_per_sec,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
},
{
.procname = "icmp_msgs_burst",
.data = &sysctl_icmp_msgs_burst,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
},
{
.procname = "udp_mem",
.data = &sysctl_udp_mem,
.maxlen = sizeof(sysctl_udp_mem),
.mode = 0644,
.proc_handler = proc_doulongvec_minmax,
},
{ }
};
static struct ctl_table ipv4_net_table[] = {
{
.procname = "icmp_echo_ignore_all",
.data = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "icmp_echo_ignore_broadcasts",
.data = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "icmp_ignore_bogus_error_responses",
.data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "icmp_errors_use_inbound_ifaddr",
.data = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "icmp_ratelimit",
.data = &init_net.ipv4.sysctl_icmp_ratelimit,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_ms_jiffies,
},
{
.procname = "icmp_ratemask",
.data = &init_net.ipv4.sysctl_icmp_ratemask,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "ping_group_range",
.data = &init_net.ipv4.ping_group_range.range,
.maxlen = sizeof(gid_t)*2,
.mode = 0644,
.proc_handler = ipv4_ping_group_range,
},
{
.procname = "tcp_ecn",
.data = &init_net.ipv4.sysctl_tcp_ecn,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_ecn_fallback",
.data = &init_net.ipv4.sysctl_tcp_ecn_fallback,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "ip_dynaddr",
.data = &init_net.ipv4.sysctl_ip_dynaddr,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "ip_early_demux",
.data = &init_net.ipv4.sysctl_ip_early_demux,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "udp_early_demux",
.data = &init_net.ipv4.sysctl_udp_early_demux,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_udp_early_demux
},
{
.procname = "tcp_early_demux",
.data = &init_net.ipv4.sysctl_tcp_early_demux,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_tcp_early_demux
},
{
.procname = "ip_default_ttl",
.data = &init_net.ipv4.sysctl_ip_default_ttl,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &ip_ttl_min,
.extra2 = &ip_ttl_max,
},
{
.procname = "ip_local_port_range",
.maxlen = sizeof(init_net.ipv4.ip_local_ports.range),
.data = &init_net.ipv4.ip_local_ports.range,
.mode = 0644,
.proc_handler = ipv4_local_port_range,
},
{
.procname = "ip_local_reserved_ports",
.data = &init_net.ipv4.sysctl_local_reserved_ports,
.maxlen = 65536,
.mode = 0644,
.proc_handler = proc_do_large_bitmap,
},
{
.procname = "ip_no_pmtu_disc",
.data = &init_net.ipv4.sysctl_ip_no_pmtu_disc,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "ip_forward_use_pmtu",
.data = &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "ip_nonlocal_bind",
.data = &init_net.ipv4.sysctl_ip_nonlocal_bind,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "fwmark_reflect",
.data = &init_net.ipv4.sysctl_fwmark_reflect,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "tcp_fwmark_accept",
.data = &init_net.ipv4.sysctl_tcp_fwmark_accept,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
#ifdef CONFIG_NET_L3_MASTER_DEV
{
.procname = "tcp_l3mdev_accept",
.data = &init_net.ipv4.sysctl_tcp_l3mdev_accept,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &one,
},
#endif
{
.procname = "tcp_mtu_probing",
.data = &init_net.ipv4.sysctl_tcp_mtu_probing,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "tcp_base_mss",
.data = &init_net.ipv4.sysctl_tcp_base_mss,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "tcp_probe_threshold",
.data = &init_net.ipv4.sysctl_tcp_probe_threshold,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "tcp_probe_interval",
.data = &init_net.ipv4.sysctl_tcp_probe_interval,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "igmp_link_local_mcast_reports",
.data = &init_net.ipv4.sysctl_igmp_llm_reports,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "igmp_max_memberships",
.data = &init_net.ipv4.sysctl_igmp_max_memberships,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "igmp_max_msf",
.data = &init_net.ipv4.sysctl_igmp_max_msf,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
#ifdef CONFIG_IP_MULTICAST
{
.procname = "igmp_qrv",
.data = &init_net.ipv4.sysctl_igmp_qrv,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &one
},
#endif
{
.procname = "tcp_congestion_control",
.data = &init_net.ipv4.tcp_congestion_control,
.mode = 0644,
.maxlen = TCP_CA_NAME_MAX,
.proc_handler = proc_tcp_congestion_control,
},
{
.procname = "tcp_keepalive_time",
.data = &init_net.ipv4.sysctl_tcp_keepalive_time,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "tcp_keepalive_probes",
.data = &init_net.ipv4.sysctl_tcp_keepalive_probes,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_keepalive_intvl",
.data = &init_net.ipv4.sysctl_tcp_keepalive_intvl,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "tcp_syn_retries",
.data = &init_net.ipv4.sysctl_tcp_syn_retries,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &tcp_syn_retries_min,
.extra2 = &tcp_syn_retries_max
},
{
.procname = "tcp_synack_retries",
.data = &init_net.ipv4.sysctl_tcp_synack_retries,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
#ifdef CONFIG_SYN_COOKIES
{
.procname = "tcp_syncookies",
.data = &init_net.ipv4.sysctl_tcp_syncookies,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
#endif
{
.procname = "tcp_reordering",
.data = &init_net.ipv4.sysctl_tcp_reordering,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_retries1",
.data = &init_net.ipv4.sysctl_tcp_retries1,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra2 = &tcp_retr1_max
},
{
.procname = "tcp_retries2",
.data = &init_net.ipv4.sysctl_tcp_retries2,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_orphan_retries",
.data = &init_net.ipv4.sysctl_tcp_orphan_retries,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_fin_timeout",
.data = &init_net.ipv4.sysctl_tcp_fin_timeout,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "tcp_notsent_lowat",
.data = &init_net.ipv4.sysctl_tcp_notsent_lowat,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_douintvec,
},
{
.procname = "tcp_tw_reuse",
.data = &init_net.ipv4.sysctl_tcp_tw_reuse,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &two,
},
{
.procname = "tcp_max_tw_buckets",
.data = &init_net.ipv4.tcp_death_row.sysctl_max_tw_buckets,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_max_syn_backlog",
.data = &init_net.ipv4.sysctl_max_syn_backlog,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_fastopen",
.data = &init_net.ipv4.sysctl_tcp_fastopen,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "tcp_fastopen_key",
.mode = 0600,
.data = &init_net.ipv4.sysctl_tcp_fastopen,
.maxlen = ((TCP_FASTOPEN_KEY_LENGTH * 2) + 10),
.proc_handler = proc_tcp_fastopen_key,
},
{
.procname = "tcp_fastopen_blackhole_timeout_sec",
.data = &init_net.ipv4.sysctl_tcp_fastopen_blackhole_timeout,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_tfo_blackhole_detect_timeout,
.extra1 = &zero,
},
#ifdef CONFIG_IP_ROUTE_MULTIPATH
{
.procname = "fib_multipath_use_neigh",
.data = &init_net.ipv4.sysctl_fib_multipath_use_neigh,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &one,
},
{
.procname = "fib_multipath_hash_policy",
.data = &init_net.ipv4.sysctl_fib_multipath_hash_policy,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_fib_multipath_hash_policy,
.extra1 = &zero,
.extra2 = &one,
},
#endif
{
.procname = "ip_unprivileged_port_start",
.maxlen = sizeof(int),
.data = &init_net.ipv4.sysctl_ip_prot_sock,
.mode = 0644,
.proc_handler = ipv4_privileged_ports,
},
#ifdef CONFIG_NET_L3_MASTER_DEV
{
.procname = "udp_l3mdev_accept",
.data = &init_net.ipv4.sysctl_udp_l3mdev_accept,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &one,
},
#endif
{
.procname = "tcp_sack",
.data = &init_net.ipv4.sysctl_tcp_sack,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_window_scaling",
.data = &init_net.ipv4.sysctl_tcp_window_scaling,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_timestamps",
.data = &init_net.ipv4.sysctl_tcp_timestamps,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_early_retrans",
.data = &init_net.ipv4.sysctl_tcp_early_retrans,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &four,
},
{
.procname = "tcp_recovery",
.data = &init_net.ipv4.sysctl_tcp_recovery,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "tcp_thin_linear_timeouts",
.data = &init_net.ipv4.sysctl_tcp_thin_linear_timeouts,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_slow_start_after_idle",
.data = &init_net.ipv4.sysctl_tcp_slow_start_after_idle,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_retrans_collapse",
.data = &init_net.ipv4.sysctl_tcp_retrans_collapse,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_stdurg",
.data = &init_net.ipv4.sysctl_tcp_stdurg,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_rfc1337",
.data = &init_net.ipv4.sysctl_tcp_rfc1337,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_abort_on_overflow",
.data = &init_net.ipv4.sysctl_tcp_abort_on_overflow,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_fack",
.data = &init_net.ipv4.sysctl_tcp_fack,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_max_reordering",
.data = &init_net.ipv4.sysctl_tcp_max_reordering,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_dsack",
.data = &init_net.ipv4.sysctl_tcp_dsack,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_app_win",
.data = &init_net.ipv4.sysctl_tcp_app_win,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_adv_win_scale",
.data = &init_net.ipv4.sysctl_tcp_adv_win_scale,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &tcp_adv_win_scale_min,
.extra2 = &tcp_adv_win_scale_max,
},
{
.procname = "tcp_frto",
.data = &init_net.ipv4.sysctl_tcp_frto,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_no_metrics_save",
.data = &init_net.ipv4.sysctl_tcp_nometrics_save,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "tcp_moderate_rcvbuf",
.data = &init_net.ipv4.sysctl_tcp_moderate_rcvbuf,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "tcp_tso_win_divisor",
.data = &init_net.ipv4.sysctl_tcp_tso_win_divisor,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "tcp_workaround_signed_windows",
.data = &init_net.ipv4.sysctl_tcp_workaround_signed_windows,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_limit_output_bytes",
.data = &init_net.ipv4.sysctl_tcp_limit_output_bytes,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_challenge_ack_limit",
.data = &init_net.ipv4.sysctl_tcp_challenge_ack_limit,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_min_tso_segs",
.data = &init_net.ipv4.sysctl_tcp_min_tso_segs,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &one,
.extra2 = &gso_max_segs,
},
{
.procname = "tcp_min_rtt_wlen",
.data = &init_net.ipv4.sysctl_tcp_min_rtt_wlen,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec
},
{
.procname = "tcp_autocorking",
.data = &init_net.ipv4.sysctl_tcp_autocorking,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &one,
},
{
.procname = "tcp_invalid_ratelimit",
.data = &init_net.ipv4.sysctl_tcp_invalid_ratelimit,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_ms_jiffies,
},
{
.procname = "tcp_pacing_ss_ratio",
.data = &init_net.ipv4.sysctl_tcp_pacing_ss_ratio,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &thousand,
},
{
.procname = "tcp_pacing_ca_ratio",
.data = &init_net.ipv4.sysctl_tcp_pacing_ca_ratio,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &thousand,
},
{
.procname = "tcp_wmem",
.data = &init_net.ipv4.sysctl_tcp_wmem,
.maxlen = sizeof(init_net.ipv4.sysctl_tcp_wmem),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &one,
},
{
.procname = "tcp_rmem",
.data = &init_net.ipv4.sysctl_tcp_rmem,
.maxlen = sizeof(init_net.ipv4.sysctl_tcp_rmem),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &one,
},
{
.procname = "tcp_comp_sack_delay_ns",
.data = &init_net.ipv4.sysctl_tcp_comp_sack_delay_ns,
.maxlen = sizeof(unsigned long),
.mode = 0644,
.proc_handler = proc_doulongvec_minmax,
},
{
.procname = "tcp_comp_sack_nr",
.data = &init_net.ipv4.sysctl_tcp_comp_sack_nr,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &zero,
.extra2 = &comp_sack_nr_max,
},
{
.procname = "udp_rmem_min",
.data = &init_net.ipv4.sysctl_udp_rmem_min,
.maxlen = sizeof(init_net.ipv4.sysctl_udp_rmem_min),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &one
},
{
.procname = "udp_wmem_min",
.data = &init_net.ipv4.sysctl_udp_wmem_min,
.maxlen = sizeof(init_net.ipv4.sysctl_udp_wmem_min),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
.extra1 = &one
},
{ }
};
static __net_init int ipv4_sysctl_init_net(struct net *net)
{
struct ctl_table *table;
table = ipv4_net_table;
if (!net_eq(net, &init_net)) {
int i;
table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
if (!table)
goto err_alloc;
/* Update the variables to point into the current struct net */
for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++)
table[i].data += (void *)net - (void *)&init_net;
}
net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
if (!net->ipv4.ipv4_hdr)
goto err_reg;
net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
if (!net->ipv4.sysctl_local_reserved_ports)
goto err_ports;
return 0;
err_ports:
unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
err_reg:
if (!net_eq(net, &init_net))
kfree(table);
err_alloc:
return -ENOMEM;
}
static __net_exit void ipv4_sysctl_exit_net(struct net *net)
{
struct ctl_table *table;
kfree(net->ipv4.sysctl_local_reserved_ports);
table = net->ipv4.ipv4_hdr->ctl_table_arg;
unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
kfree(table);
}
static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
.init = ipv4_sysctl_init_net,
.exit = ipv4_sysctl_exit_net,
};
static __init int sysctl_ipv4_init(void)
{
struct ctl_table_header *hdr;
hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
if (!hdr)
return -ENOMEM;
if (register_pernet_subsys(&ipv4_sysctl_ops)) {
unregister_net_sysctl_table(hdr);
return -ENOMEM;
}
return 0;
}
__initcall(sysctl_ipv4_init);