1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2006 Patrick McHardy <kaber@trash.net>
4 */
5
6 #include <linux/module.h>
7 #include <linux/init.h>
8 #include <linux/skbuff.h>
9
10 #include <linux/netfilter/x_tables.h>
11 #include <linux/netfilter/xt_NFLOG.h>
12 #include <net/netfilter/nf_log.h>
13
14 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
15 MODULE_DESCRIPTION("Xtables: packet logging to netlink using NFLOG");
16 MODULE_LICENSE("GPL");
17 MODULE_ALIAS("ipt_NFLOG");
18 MODULE_ALIAS("ip6t_NFLOG");
19
20 static unsigned int
nflog_tg(struct sk_buff * skb,const struct xt_action_param * par)21 nflog_tg(struct sk_buff *skb, const struct xt_action_param *par)
22 {
23 const struct xt_nflog_info *info = par->targinfo;
24 struct net *net = xt_net(par);
25 struct nf_loginfo li;
26
27 li.type = NF_LOG_TYPE_ULOG;
28 li.u.ulog.copy_len = info->len;
29 li.u.ulog.group = info->group;
30 li.u.ulog.qthreshold = info->threshold;
31 li.u.ulog.flags = 0;
32
33 if (info->flags & XT_NFLOG_F_COPY_LEN)
34 li.u.ulog.flags |= NF_LOG_F_COPY_LEN;
35
36 nf_log_packet(net, xt_family(par), xt_hooknum(par), skb, xt_in(par),
37 xt_out(par), &li, "%s", info->prefix);
38
39 return XT_CONTINUE;
40 }
41
nflog_tg_check(const struct xt_tgchk_param * par)42 static int nflog_tg_check(const struct xt_tgchk_param *par)
43 {
44 const struct xt_nflog_info *info = par->targinfo;
45 int ret;
46
47 if (info->flags & ~XT_NFLOG_MASK)
48 return -EINVAL;
49 if (info->prefix[sizeof(info->prefix) - 1] != '\0')
50 return -EINVAL;
51
52 ret = nf_logger_find_get(par->family, NF_LOG_TYPE_ULOG);
53 if (ret != 0 && !par->nft_compat) {
54 request_module("%s", "nfnetlink_log");
55
56 ret = nf_logger_find_get(par->family, NF_LOG_TYPE_ULOG);
57 }
58
59 return ret;
60 }
61
nflog_tg_destroy(const struct xt_tgdtor_param * par)62 static void nflog_tg_destroy(const struct xt_tgdtor_param *par)
63 {
64 nf_logger_put(par->family, NF_LOG_TYPE_ULOG);
65 }
66
67 static struct xt_target nflog_tg_reg[] __read_mostly = {
68 {
69 .name = "NFLOG",
70 .revision = 0,
71 .family = NFPROTO_IPV4,
72 .checkentry = nflog_tg_check,
73 .destroy = nflog_tg_destroy,
74 .target = nflog_tg,
75 .targetsize = sizeof(struct xt_nflog_info),
76 .me = THIS_MODULE,
77 },
78 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
79 {
80 .name = "NFLOG",
81 .revision = 0,
82 .family = NFPROTO_IPV6,
83 .checkentry = nflog_tg_check,
84 .destroy = nflog_tg_destroy,
85 .target = nflog_tg,
86 .targetsize = sizeof(struct xt_nflog_info),
87 .me = THIS_MODULE,
88 },
89 #endif
90 };
91
nflog_tg_init(void)92 static int __init nflog_tg_init(void)
93 {
94 return xt_register_targets(nflog_tg_reg, ARRAY_SIZE(nflog_tg_reg));
95 }
96
nflog_tg_exit(void)97 static void __exit nflog_tg_exit(void)
98 {
99 xt_unregister_targets(nflog_tg_reg, ARRAY_SIZE(nflog_tg_reg));
100 }
101
102 module_init(nflog_tg_init);
103 module_exit(nflog_tg_exit);
104 MODULE_SOFTDEP("pre: nfnetlink_log");
105