This patch introduces new sysctl toggle for enabling lightweight tunnel netfilter hooks. Signed-off-by: proelbtn <contact@xxxxxxxxxxxx> --- .../networking/nf_conntrack-sysctl.rst | 7 ++ include/net/lwtunnel.h | 3 + include/net/netfilter/nf_hooks_lwtunnel.h | 15 +++++ net/core/lwtunnel.c | 3 + net/netfilter/Makefile | 3 + net/netfilter/nf_conntrack_standalone.c | 15 +++++ net/netfilter/nf_hooks_lwtunnel.c | 66 +++++++++++++++++++ 7 files changed, 112 insertions(+) create mode 100644 include/net/netfilter/nf_hooks_lwtunnel.h create mode 100644 net/netfilter/nf_hooks_lwtunnel.c diff --git a/Documentation/networking/nf_conntrack-sysctl.rst b/Documentation/networking/nf_conntrack-sysctl.rst index 024d784157c8..34ca762ea56f 100644 --- a/Documentation/networking/nf_conntrack-sysctl.rst +++ b/Documentation/networking/nf_conntrack-sysctl.rst @@ -184,6 +184,13 @@ nf_conntrack_gre_timeout_stream - INTEGER (seconds) This extended timeout will be used in case there is an GRE stream detected. +nf_hooks_lwtunnel - BOOLEAN + - 0 - disabled (default) + - not 0 - enabled + + If this option is enabled, the lightweight tunnel netfilter hooks are + enabled. This option cannot be disabled once it is enabled. + nf_flowtable_tcp_timeout - INTEGER (seconds) default 30 diff --git a/include/net/lwtunnel.h b/include/net/lwtunnel.h index 05cfd6ff6528..6f15e6fa154e 100644 --- a/include/net/lwtunnel.h +++ b/include/net/lwtunnel.h @@ -51,6 +51,9 @@ struct lwtunnel_encap_ops { }; #ifdef CONFIG_LWTUNNEL + +DECLARE_STATIC_KEY_FALSE(nf_hooks_lwtunnel_enabled); + void lwtstate_free(struct lwtunnel_state *lws); static inline struct lwtunnel_state * diff --git a/include/net/netfilter/nf_hooks_lwtunnel.h b/include/net/netfilter/nf_hooks_lwtunnel.h new file mode 100644 index 000000000000..f10ee2ccbdc8 --- /dev/null +++ b/include/net/netfilter/nf_hooks_lwtunnel.h @@ -0,0 +1,15 @@ +#include <linux/sysctl.h> +#include <linux/types.h> + +#ifdef CONFIG_LWTUNNEL +int nf_hooks_lwtunnel_sysctl_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, + loff_t *ppos); +#else +int nf_hooks_lwtunnel_sysctl_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, + loff_t *ppos) +{ + return 0; +} +#endif diff --git a/net/core/lwtunnel.c b/net/core/lwtunnel.c index 8ec7d13d2860..3e6960b455e1 100644 --- a/net/core/lwtunnel.c +++ b/net/core/lwtunnel.c @@ -23,6 +23,9 @@ #include <net/ip6_fib.h> #include <net/rtnh.h> +DEFINE_STATIC_KEY_FALSE(nf_hooks_lwtunnel_enabled); +EXPORT_SYMBOL_GPL(nf_hooks_lwtunnel_enabled); + #ifdef CONFIG_MODULES static const char *lwtunnel_encap_str(enum lwtunnel_encap_types encap_type) diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 049890e00a3d..aab20e575ecd 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -212,3 +212,6 @@ obj-$(CONFIG_IP_SET) += ipset/ # IPVS obj-$(CONFIG_IP_VS) += ipvs/ + +# lwtunnel +obj-$(CONFIG_LWTUNNEL) += nf_hooks_lwtunnel.o diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c index e84b499b7bfa..7e0d956da51d 100644 --- a/net/netfilter/nf_conntrack_standalone.c +++ b/net/netfilter/nf_conntrack_standalone.c @@ -22,6 +22,9 @@ #include <net/netfilter/nf_conntrack_acct.h> #include <net/netfilter/nf_conntrack_zones.h> #include <net/netfilter/nf_conntrack_timestamp.h> +#ifdef CONFIG_LWTUNNEL +#include <net/netfilter/nf_hooks_lwtunnel.h> +#endif #include <linux/rculist_nulls.h> static bool enable_hooks __read_mostly; @@ -612,6 +615,9 @@ enum nf_ct_sysctl_index { NF_SYSCTL_CT_PROTO_TIMEOUT_GRE, NF_SYSCTL_CT_PROTO_TIMEOUT_GRE_STREAM, #endif +#ifdef CONFIG_LWTUNNEL + NF_SYSCTL_CT_LWTUNNEL, +#endif __NF_SYSCTL_CT_LAST_SYSCTL, }; @@ -958,6 +964,15 @@ static struct ctl_table nf_ct_sysctl_table[] = { .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, +#endif +#ifdef CONFIG_LWTUNNEL + [NF_SYSCTL_CT_LWTUNNEL] = { + .procname = "nf_hooks_lwtunnel", + .data = NULL, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = nf_hooks_lwtunnel_sysctl_handler, + }, #endif {} }; diff --git a/net/netfilter/nf_hooks_lwtunnel.c b/net/netfilter/nf_hooks_lwtunnel.c new file mode 100644 index 000000000000..15b79469048f --- /dev/null +++ b/net/netfilter/nf_hooks_lwtunnel.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/sysctl.h> +#include <net/lwtunnel.h> +#include <net/netfilter/nf_hooks_lwtunnel.h> + +static inline int nf_hooks_lwtunnel_get(void) +{ + if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled)) + return 1; + else + return 0; +} + +static inline int nf_hooks_lwtunnel_set(int enable) +{ + if (static_branch_unlikely(&nf_hooks_lwtunnel_enabled)) { + if (!enable) + return -EBUSY; + } else if (enable) { + static_branch_enable(&nf_hooks_lwtunnel_enabled); + } + + return 0; +} + +#ifdef CONFIG_SYSCTL + +int nf_hooks_lwtunnel_sysctl_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, + loff_t *ppos) +{ + int proc_nf_hooks_lwtunnel_enabled = 0; + struct ctl_table tmp = { + .procname = table->procname, + .data = &proc_nf_hooks_lwtunnel_enabled, + .maxlen = sizeof(int), + .mode = table->mode, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }; + int ret; + + if (!write) + proc_nf_hooks_lwtunnel_enabled = nf_hooks_lwtunnel_get(); + + ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); + + if (write && ret == 0) + ret = nf_hooks_lwtunnel_set(proc_nf_hooks_lwtunnel_enabled); + + return ret; +} +EXPORT_SYMBOL_GPL(nf_hooks_lwtunnel_sysctl_handler); + +#else // CONFIG_SYSCTL + +int nf_hooks_lwtunnel_sysctl_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, + loff_t *ppos) +{ + return 0; +} +EXPORT_SYMBOL_GPL(nf_hooks_lwtunnel_sysctl_handler); + +#endif -- 2.25.1