Thomas Gleixner | d2912cb | 2019-06-04 10:11:33 +0200 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 2 | /* |
| 3 | * (C) 2013 Astaro GmbH & Co KG |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 4 | */ |
| 5 | |
| 6 | #include <linux/module.h> |
| 7 | #include <linux/skbuff.h> |
| 8 | #include <net/netfilter/nf_conntrack.h> |
Florian Westphal | 857ed31 | 2016-07-21 12:51:17 +0200 | [diff] [blame] | 9 | #include <net/netfilter/nf_conntrack_ecache.h> |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 10 | #include <net/netfilter/nf_conntrack_labels.h> |
| 11 | #include <linux/netfilter/x_tables.h> |
| 12 | |
| 13 | MODULE_LICENSE("GPL"); |
| 14 | MODULE_AUTHOR("Florian Westphal <fw@strlen.de>"); |
Colin Ian King | 1de6f33 | 2019-04-18 18:00:56 +0100 | [diff] [blame] | 15 | MODULE_DESCRIPTION("Xtables: add/match connection tracking labels"); |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 16 | MODULE_ALIAS("ipt_connlabel"); |
| 17 | MODULE_ALIAS("ip6t_connlabel"); |
| 18 | |
| 19 | static bool |
| 20 | connlabel_mt(const struct sk_buff *skb, struct xt_action_param *par) |
| 21 | { |
| 22 | const struct xt_connlabel_mtinfo *info = par->matchinfo; |
| 23 | enum ip_conntrack_info ctinfo; |
Florian Westphal | 857ed31 | 2016-07-21 12:51:17 +0200 | [diff] [blame] | 24 | struct nf_conn_labels *labels; |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 25 | struct nf_conn *ct; |
| 26 | bool invert = info->options & XT_CONNLABEL_OP_INVERT; |
| 27 | |
| 28 | ct = nf_ct_get(skb, &ctinfo); |
Florian Westphal | ab8bc7e | 2017-04-14 20:31:09 +0200 | [diff] [blame] | 29 | if (ct == NULL) |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 30 | return invert; |
| 31 | |
Florian Westphal | 857ed31 | 2016-07-21 12:51:17 +0200 | [diff] [blame] | 32 | labels = nf_ct_labels_find(ct); |
| 33 | if (!labels) |
| 34 | return invert; |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 35 | |
Florian Westphal | 857ed31 | 2016-07-21 12:51:17 +0200 | [diff] [blame] | 36 | if (test_bit(info->bit, labels->bits)) |
| 37 | return !invert; |
| 38 | |
| 39 | if (info->options & XT_CONNLABEL_OP_SET) { |
| 40 | if (!test_and_set_bit(info->bit, labels->bits)) |
| 41 | nf_conntrack_event_cache(IPCT_LABEL, ct); |
| 42 | |
| 43 | return !invert; |
| 44 | } |
| 45 | |
| 46 | return invert; |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 47 | } |
| 48 | |
| 49 | static int connlabel_mt_check(const struct xt_mtchk_param *par) |
| 50 | { |
| 51 | const int options = XT_CONNLABEL_OP_INVERT | |
| 52 | XT_CONNLABEL_OP_SET; |
| 53 | struct xt_connlabel_mtinfo *info = par->matchinfo; |
| 54 | int ret; |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 55 | |
| 56 | if (info->options & ~options) { |
Florian Westphal | b260664 | 2018-02-09 15:52:07 +0100 | [diff] [blame] | 57 | pr_info_ratelimited("Unknown options in mask %x\n", |
| 58 | info->options); |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 59 | return -EINVAL; |
| 60 | } |
| 61 | |
Florian Westphal | ecb2421 | 2016-11-15 21:36:40 +0100 | [diff] [blame] | 62 | ret = nf_ct_netns_get(par->net, par->family); |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 63 | if (ret < 0) { |
Florian Westphal | b260664 | 2018-02-09 15:52:07 +0100 | [diff] [blame] | 64 | pr_info_ratelimited("cannot load conntrack support for proto=%u\n", |
| 65 | par->family); |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 66 | return ret; |
| 67 | } |
| 68 | |
Florian Westphal | adff6c6 | 2016-04-12 18:14:25 +0200 | [diff] [blame] | 69 | ret = nf_connlabels_get(par->net, info->bit); |
Joe Stringer | 86ca02e | 2015-08-26 11:31:51 -0700 | [diff] [blame] | 70 | if (ret < 0) |
Florian Westphal | ecb2421 | 2016-11-15 21:36:40 +0100 | [diff] [blame] | 71 | nf_ct_netns_put(par->net, par->family); |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 72 | return ret; |
| 73 | } |
| 74 | |
| 75 | static void connlabel_mt_destroy(const struct xt_mtdtor_param *par) |
| 76 | { |
Joe Stringer | 86ca02e | 2015-08-26 11:31:51 -0700 | [diff] [blame] | 77 | nf_connlabels_put(par->net); |
Florian Westphal | ecb2421 | 2016-11-15 21:36:40 +0100 | [diff] [blame] | 78 | nf_ct_netns_put(par->net, par->family); |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 79 | } |
| 80 | |
| 81 | static struct xt_match connlabels_mt_reg __read_mostly = { |
| 82 | .name = "connlabel", |
| 83 | .family = NFPROTO_UNSPEC, |
| 84 | .checkentry = connlabel_mt_check, |
| 85 | .match = connlabel_mt, |
| 86 | .matchsize = sizeof(struct xt_connlabel_mtinfo), |
| 87 | .destroy = connlabel_mt_destroy, |
| 88 | .me = THIS_MODULE, |
| 89 | }; |
| 90 | |
| 91 | static int __init connlabel_mt_init(void) |
| 92 | { |
| 93 | return xt_register_match(&connlabels_mt_reg); |
| 94 | } |
| 95 | |
| 96 | static void __exit connlabel_mt_exit(void) |
| 97 | { |
| 98 | xt_unregister_match(&connlabels_mt_reg); |
| 99 | } |
| 100 | |
| 101 | module_init(connlabel_mt_init); |
| 102 | module_exit(connlabel_mt_exit); |