From adf82accc5f526f1e812f1a8df7292fef7dad19a Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 9 Apr 2019 10:44:07 +0200 Subject: netfilter: x_tables: merge ip and ipv6 masquerade modules No need to have separate modules for this. before: text data bss dec filename 2038 1168 0 3206 net/ipv4/netfilter/ipt_MASQUERADE.ko 1526 1024 0 2550 net/ipv6/netfilter/ip6t_MASQUERADE.ko after: text data bss dec filename 2521 1296 0 3817 net/netfilter/xt_MASQUERADE.ko Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/Kconfig | 14 +++++ net/netfilter/Makefile | 1 + net/netfilter/xt_MASQUERADE.c | 143 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 158 insertions(+) create mode 100644 net/netfilter/xt_MASQUERADE.c (limited to 'net/netfilter') diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index f4384c096d0d..02b281d3c167 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -997,6 +997,20 @@ config NETFILTER_XT_TARGET_REDIRECT To compile it as a module, choose M here. If unsure, say N. +config NETFILTER_XT_TARGET_MASQUERADE + tristate "MASQUERADE target support" + depends on NF_NAT + default m if NETFILTER_ADVANCED=n + select NF_NAT_MASQUERADE + help + Masquerading is a special case of NAT: all outgoing connections are + changed to seem to come from a particular interface's address, and + if the interface goes down, those connections are lost. This is + only useful for dialup accounts with dynamic IP address (ie. your IP + address will be different on next dialup). + + To compile it as a module, choose M here. If unsure, say N. + config NETFILTER_XT_TARGET_TEE tristate '"TEE" - packet cloning to alternate destination' depends on NETFILTER_ADVANCED diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index afbf475e02b2..72cca6b48960 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -148,6 +148,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_NFLOG) += xt_NFLOG.o obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE) += xt_NFQUEUE.o obj-$(CONFIG_NETFILTER_XT_TARGET_RATEEST) += xt_RATEEST.o obj-$(CONFIG_NETFILTER_XT_TARGET_REDIRECT) += xt_REDIRECT.o +obj-$(CONFIG_NETFILTER_XT_TARGET_MASQUERADE) += xt_MASQUERADE.o obj-$(CONFIG_NETFILTER_XT_TARGET_SECMARK) += xt_SECMARK.o obj-$(CONFIG_NETFILTER_XT_TARGET_TPROXY) += xt_TPROXY.o obj-$(CONFIG_NETFILTER_XT_TARGET_TCPMSS) += xt_TCPMSS.o diff --git a/net/netfilter/xt_MASQUERADE.c b/net/netfilter/xt_MASQUERADE.c new file mode 100644 index 000000000000..96d884718749 --- /dev/null +++ b/net/netfilter/xt_MASQUERADE.c @@ -0,0 +1,143 @@ +/* Masquerade. Simple mapping which alters range to a local IP address + (depending on route). */ + +/* (C) 1999-2001 Paul `Rusty' Russell + * (C) 2002-2006 Netfilter Core Team + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include +#include +#include +#include + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Netfilter Core Team "); +MODULE_DESCRIPTION("Xtables: automatic-address SNAT"); + +/* FIXME: Multiple targets. --RR */ +static int masquerade_tg_check(const struct xt_tgchk_param *par) +{ + const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo; + + if (mr->range[0].flags & NF_NAT_RANGE_MAP_IPS) { + pr_debug("bad MAP_IPS.\n"); + return -EINVAL; + } + if (mr->rangesize != 1) { + pr_debug("bad rangesize %u\n", mr->rangesize); + return -EINVAL; + } + return nf_ct_netns_get(par->net, par->family); +} + +static unsigned int +masquerade_tg(struct sk_buff *skb, const struct xt_action_param *par) +{ + struct nf_nat_range2 range; + const struct nf_nat_ipv4_multi_range_compat *mr; + + mr = par->targinfo; + range.flags = mr->range[0].flags; + range.min_proto = mr->range[0].min; + range.max_proto = mr->range[0].max; + + return nf_nat_masquerade_ipv4(skb, xt_hooknum(par), &range, + xt_out(par)); +} + +static void masquerade_tg_destroy(const struct xt_tgdtor_param *par) +{ + nf_ct_netns_put(par->net, par->family); +} + +#if IS_ENABLED(CONFIG_IPV6) +static unsigned int +masquerade_tg6(struct sk_buff *skb, const struct xt_action_param *par) +{ + return nf_nat_masquerade_ipv6(skb, par->targinfo, xt_out(par)); +} + +static int masquerade_tg6_checkentry(const struct xt_tgchk_param *par) +{ + const struct nf_nat_range2 *range = par->targinfo; + + if (range->flags & NF_NAT_RANGE_MAP_IPS) + return -EINVAL; + + return nf_ct_netns_get(par->net, par->family); +} +#endif + +static struct xt_target masquerade_tg_reg[] __read_mostly = { + { +#if IS_ENABLED(CONFIG_IPV6) + .name = "MASQUERADE", + .family = NFPROTO_IPV6, + .target = masquerade_tg6, + .targetsize = sizeof(struct nf_nat_range), + .table = "nat", + .hooks = 1 << NF_INET_POST_ROUTING, + .checkentry = masquerade_tg6_checkentry, + .destroy = masquerade_tg_destroy, + .me = THIS_MODULE, + }, { +#endif + .name = "MASQUERADE", + .family = NFPROTO_IPV4, + .target = masquerade_tg, + .targetsize = sizeof(struct nf_nat_ipv4_multi_range_compat), + .table = "nat", + .hooks = 1 << NF_INET_POST_ROUTING, + .checkentry = masquerade_tg_check, + .destroy = masquerade_tg_destroy, + .me = THIS_MODULE, + } +}; + +static int __init masquerade_tg_init(void) +{ + int ret; + + ret = xt_register_targets(masquerade_tg_reg, + ARRAY_SIZE(masquerade_tg_reg)); + if (ret) + return ret; + + ret = nf_nat_masquerade_ipv4_register_notifier(); + if (ret) { + xt_unregister_targets(masquerade_tg_reg, + ARRAY_SIZE(masquerade_tg_reg)); + return ret; + } + +#if IS_ENABLED(CONFIG_IPV6) + ret = nf_nat_masquerade_ipv6_register_notifier(); + if (ret) { + xt_unregister_targets(masquerade_tg_reg, + ARRAY_SIZE(masquerade_tg_reg)); + nf_nat_masquerade_ipv4_unregister_notifier(); + return ret; + } +#endif + return ret; +} + +static void __exit masquerade_tg_exit(void) +{ + xt_unregister_targets(masquerade_tg_reg, ARRAY_SIZE(masquerade_tg_reg)); + nf_nat_masquerade_ipv4_unregister_notifier(); +#if IS_ENABLED(CONFIG_IPV6) + nf_nat_masquerade_ipv6_unregister_notifier(); +#endif +} + +module_init(masquerade_tg_init); +module_exit(masquerade_tg_exit); +#if IS_ENABLED(CONFIG_IPV6) +MODULE_ALIAS("ip6t_MASQUERADE"); +#endif +MODULE_ALIAS("ipt_MASQUERADE"); -- cgit v1.2.3