1 // SPDX-License-Identifier: GPL-2.0-only
2 /* This is a module which is used to mark packets for tracing.
3 */
4 #include <linux/module.h>
5 #include <linux/skbuff.h>
6
7 #include <linux/netfilter/x_tables.h>
8 #include <net/netfilter/nf_log.h>
9
10 MODULE_DESCRIPTION("Xtables: packet flow tracing");
11 MODULE_LICENSE("GPL");
12 MODULE_ALIAS("ipt_TRACE");
13 MODULE_ALIAS("ip6t_TRACE");
14
trace_tg_check(const struct xt_tgchk_param * par)15 static int trace_tg_check(const struct xt_tgchk_param *par)
16 {
17 return nf_logger_find_get(par->family, NF_LOG_TYPE_LOG);
18 }
19
trace_tg_destroy(const struct xt_tgdtor_param * par)20 static void trace_tg_destroy(const struct xt_tgdtor_param *par)
21 {
22 nf_logger_put(par->family, NF_LOG_TYPE_LOG);
23 }
24
25 static unsigned int
trace_tg(struct sk_buff * skb,const struct xt_action_param * par)26 trace_tg(struct sk_buff *skb, const struct xt_action_param *par)
27 {
28 skb->nf_trace = 1;
29 return XT_CONTINUE;
30 }
31
32 static struct xt_target trace_tg_reg __read_mostly = {
33 .name = "TRACE",
34 .revision = 0,
35 .family = NFPROTO_UNSPEC,
36 .table = "raw",
37 .target = trace_tg,
38 .checkentry = trace_tg_check,
39 .destroy = trace_tg_destroy,
40 .me = THIS_MODULE,
41 };
42
trace_tg_init(void)43 static int __init trace_tg_init(void)
44 {
45 return xt_register_target(&trace_tg_reg);
46 }
47
trace_tg_exit(void)48 static void __exit trace_tg_exit(void)
49 {
50 xt_unregister_target(&trace_tg_reg);
51 }
52
53 module_init(trace_tg_init);
54 module_exit(trace_tg_exit);
55 MODULE_SOFTDEP("pre: nf_log_syslog");
56