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
14MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
15MODULE_DESCRIPTION("Xtables: packet logging to netlink using NFLOG");
16MODULE_LICENSE("GPL");
17MODULE_ALIAS("ipt_NFLOG");
18MODULE_ALIAS("ip6t_NFLOG");
19
20static unsigned int
21nflog_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, pf: xt_family(par), hooknum: xt_hooknum(par), skb, in: xt_in(par),
37 out: xt_out(par), li: &li, fmt: "%s", info->prefix);
38
39 return XT_CONTINUE;
40}
41
42static 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(pf: par->family, type: NF_LOG_TYPE_ULOG);
53 if (ret != 0 && !par->nft_compat) {
54 request_module("%s", "nfnetlink_log");
55
56 ret = nf_logger_find_get(pf: par->family, type: NF_LOG_TYPE_ULOG);
57 }
58
59 return ret;
60}
61
62static void nflog_tg_destroy(const struct xt_tgdtor_param *par)
63{
64 nf_logger_put(pf: par->family, type: NF_LOG_TYPE_ULOG);
65}
66
67static struct xt_target nflog_tg_reg __read_mostly = {
68 .name = "NFLOG",
69 .revision = 0,
70 .family = NFPROTO_UNSPEC,
71 .checkentry = nflog_tg_check,
72 .destroy = nflog_tg_destroy,
73 .target = nflog_tg,
74 .targetsize = sizeof(struct xt_nflog_info),
75 .me = THIS_MODULE,
76};
77
78static int __init nflog_tg_init(void)
79{
80 return xt_register_target(target: &nflog_tg_reg);
81}
82
83static void __exit nflog_tg_exit(void)
84{
85 xt_unregister_target(target: &nflog_tg_reg);
86}
87
88module_init(nflog_tg_init);
89module_exit(nflog_tg_exit);
90MODULE_SOFTDEP("pre: nfnetlink_log");
91

source code of linux/net/netfilter/xt_NFLOG.c