net/netfilter/xt_TRACE.c

   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
  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
  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
  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
  43 static int __init trace_tg_init(void)
  44 {
  45         return xt_register_target(&trace_tg_reg);
  46 }
  47
  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);