Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* Masquerade. Simple mapping which alters range to a local IP address |
| 2 | (depending on route). */ |
| 3 | |
| 4 | /* (C) 1999-2001 Paul `Rusty' Russell |
Jozsef Kadlecsik | 5b1158e | 2006-12-02 22:07:13 -0800 | [diff] [blame] | 5 | * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
Jan Engelhardt | ff67e4e | 2010-03-19 21:08:16 +0100 | [diff] [blame] | 11 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/types.h> |
Arnaldo Carvalho de Melo | 14c8502 | 2005-12-27 02:43:12 -0200 | [diff] [blame] | 13 | #include <linux/inetdevice.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/ip.h> |
| 15 | #include <linux/timer.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/netfilter.h> |
| 18 | #include <net/protocol.h> |
| 19 | #include <net/ip.h> |
| 20 | #include <net/checksum.h> |
Arnaldo Carvalho de Melo | 14c8502 | 2005-12-27 02:43:12 -0200 | [diff] [blame] | 21 | #include <net/route.h> |
Patrick McHardy | 587aa64 | 2007-03-14 16:37:25 -0700 | [diff] [blame] | 22 | #include <linux/netfilter_ipv4.h> |
Jan Engelhardt | 6709dbb | 2007-02-07 15:11:19 -0800 | [diff] [blame] | 23 | #include <linux/netfilter/x_tables.h> |
Patrick McHardy | c7232c9 | 2012-08-26 19:14:06 +0200 | [diff] [blame] | 24 | #include <net/netfilter/nf_nat.h> |
Arturo Borrero | 8dd33cc | 2014-09-04 14:06:33 +0200 | [diff] [blame] | 25 | #include <net/netfilter/ipv4/nf_nat_masquerade.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | |
| 27 | MODULE_LICENSE("GPL"); |
| 28 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); |
Jan Engelhardt | 2ae15b6 | 2008-01-14 23:42:28 -0800 | [diff] [blame] | 29 | MODULE_DESCRIPTION("Xtables: automatic-address SNAT"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | /* FIXME: Multiple targets. --RR */ |
Jan Engelhardt | 135367b | 2010-03-19 17:16:42 +0100 | [diff] [blame] | 32 | static int masquerade_tg_check(const struct xt_tgchk_param *par) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | { |
Patrick McHardy | cbc9f2f | 2011-12-23 13:59:49 +0100 | [diff] [blame] | 34 | const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | |
Patrick McHardy | cbc9f2f | 2011-12-23 13:59:49 +0100 | [diff] [blame] | 36 | if (mr->range[0].flags & NF_NAT_RANGE_MAP_IPS) { |
Jan Engelhardt | ff67e4e | 2010-03-19 21:08:16 +0100 | [diff] [blame] | 37 | pr_debug("bad MAP_IPS.\n"); |
Jan Engelhardt | d6b00a5 | 2010-03-25 16:34:45 +0100 | [diff] [blame] | 38 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | } |
| 40 | if (mr->rangesize != 1) { |
Jan Engelhardt | ff67e4e | 2010-03-19 21:08:16 +0100 | [diff] [blame] | 41 | pr_debug("bad rangesize %u\n", mr->rangesize); |
Jan Engelhardt | d6b00a5 | 2010-03-25 16:34:45 +0100 | [diff] [blame] | 42 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | } |
Jan Engelhardt | d6b00a5 | 2010-03-25 16:34:45 +0100 | [diff] [blame] | 44 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 45 | } |
| 46 | |
| 47 | static unsigned int |
Jan Engelhardt | 4b560b4 | 2009-07-05 19:43:26 +0200 | [diff] [blame] | 48 | masquerade_tg(struct sk_buff *skb, const struct xt_action_param *par) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | { |
Arturo Borrero | 8dd33cc | 2014-09-04 14:06:33 +0200 | [diff] [blame] | 50 | struct nf_nat_range range; |
Patrick McHardy | cbc9f2f | 2011-12-23 13:59:49 +0100 | [diff] [blame] | 51 | const struct nf_nat_ipv4_multi_range_compat *mr; |
Patrick McHardy | adcb5ad1 | 2005-09-13 13:49:15 -0700 | [diff] [blame] | 52 | |
Jan Engelhardt | 7eb3558 | 2008-10-08 11:35:19 +0200 | [diff] [blame] | 53 | mr = par->targinfo; |
Arturo Borrero | 8dd33cc | 2014-09-04 14:06:33 +0200 | [diff] [blame] | 54 | range.flags = mr->range[0].flags; |
| 55 | range.min_proto = mr->range[0].min; |
| 56 | range.max_proto = mr->range[0].max; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | |
Arturo Borrero | 8dd33cc | 2014-09-04 14:06:33 +0200 | [diff] [blame] | 58 | return nf_nat_masquerade_ipv4(skb, par->hooknum, &range, par->out); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | } |
| 60 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 61 | static struct xt_target masquerade_tg_reg __read_mostly = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | .name = "MASQUERADE", |
Jan Engelhardt | ee999d8 | 2008-10-08 11:35:01 +0200 | [diff] [blame] | 63 | .family = NFPROTO_IPV4, |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 64 | .target = masquerade_tg, |
Patrick McHardy | cbc9f2f | 2011-12-23 13:59:49 +0100 | [diff] [blame] | 65 | .targetsize = sizeof(struct nf_nat_ipv4_multi_range_compat), |
Patrick McHardy | 1d5cd90 | 2006-03-20 18:01:14 -0800 | [diff] [blame] | 66 | .table = "nat", |
Patrick McHardy | 6e23ae2 | 2007-11-19 18:53:30 -0800 | [diff] [blame] | 67 | .hooks = 1 << NF_INET_POST_ROUTING, |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 68 | .checkentry = masquerade_tg_check, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 69 | .me = THIS_MODULE, |
| 70 | }; |
| 71 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 72 | static int __init masquerade_tg_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | { |
| 74 | int ret; |
| 75 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 76 | ret = xt_register_target(&masquerade_tg_reg); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | |
Arturo Borrero | 8dd33cc | 2014-09-04 14:06:33 +0200 | [diff] [blame] | 78 | if (ret == 0) |
| 79 | nf_nat_masquerade_ipv4_register_notifier(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 80 | |
| 81 | return ret; |
| 82 | } |
| 83 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 84 | static void __exit masquerade_tg_exit(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | { |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 86 | xt_unregister_target(&masquerade_tg_reg); |
Arturo Borrero | 8dd33cc | 2014-09-04 14:06:33 +0200 | [diff] [blame] | 87 | nf_nat_masquerade_ipv4_unregister_notifier(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | } |
| 89 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 90 | module_init(masquerade_tg_init); |
| 91 | module_exit(masquerade_tg_exit); |